1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T     */
  22 /*        All Rights Reserved   */
  23 
  24 
  25 /*
  26  * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
  27  * Copyright 2015, Joyent, Inc. All rights reserved.
  28  */
  29 
  30 #include <sys/types.h>
  31 #include <sys/sysmacros.h>
  32 #include <sys/param.h>
  33 #include <sys/errno.h>
  34 #include <sys/signal.h>
  35 #include <sys/stat.h>
  36 #include <sys/proc.h>
  37 #include <sys/cred.h>
  38 #include <sys/user.h>
  39 #include <sys/vnode.h>
  40 #include <sys/file.h>
  41 #include <sys/stream.h>
  42 #include <sys/strsubr.h>
  43 #include <sys/stropts.h>
  44 #include <sys/tihdr.h>
  45 #include <sys/var.h>
  46 #include <sys/poll.h>
  47 #include <sys/termio.h>
  48 #include <sys/ttold.h>
  49 #include <sys/systm.h>
  50 #include <sys/uio.h>
  51 #include <sys/cmn_err.h>
  52 #include <sys/sad.h>
  53 #include <sys/netstack.h>
  54 #include <sys/priocntl.h>
  55 #include <sys/jioctl.h>
  56 #include <sys/procset.h>
  57 #include <sys/session.h>
  58 #include <sys/kmem.h>
  59 #include <sys/filio.h>
  60 #include <sys/vtrace.h>
  61 #include <sys/debug.h>
  62 #include <sys/strredir.h>
  63 #include <sys/fs/fifonode.h>
  64 #include <sys/fs/snode.h>
  65 #include <sys/strlog.h>
  66 #include <sys/strsun.h>
  67 #include <sys/project.h>
  68 #include <sys/kbio.h>
  69 #include <sys/msio.h>
  70 #include <sys/tty.h>
  71 #include <sys/ptyvar.h>
  72 #include <sys/vuid_event.h>
  73 #include <sys/modctl.h>
  74 #include <sys/sunddi.h>
  75 #include <sys/sunldi_impl.h>
  76 #include <sys/autoconf.h>
  77 #include <sys/policy.h>
  78 #include <sys/dld.h>
  79 #include <sys/zone.h>
  80 #include <sys/limits.h>
  81 #include <c2/audit.h>
  82 
  83 /*
  84  * This define helps improve the readability of streams code while
  85  * still maintaining a very old streams performance enhancement.  The
  86  * performance enhancement basically involved having all callers
  87  * of straccess() perform the first check that straccess() will do
  88  * locally before actually calling straccess().  (There by reducing
  89  * the number of unnecessary calls to straccess().)
  90  */
  91 #define i_straccess(x, y)       ((stp->sd_sidp == NULL) ? 0 : \
  92                                     (stp->sd_vnode->v_type == VFIFO) ? 0 : \
  93                                     straccess((x), (y)))
  94 
  95 /*
  96  * what is mblk_pull_len?
  97  *
  98  * If a streams message consists of many short messages,
  99  * a performance degradation occurs from copyout overhead.
 100  * To decrease the per mblk overhead, messages that are
 101  * likely to consist of many small mblks are pulled up into
 102  * one continuous chunk of memory.
 103  *
 104  * To avoid the processing overhead of examining every
 105  * mblk, a quick heuristic is used. If the first mblk in
 106  * the message is shorter than mblk_pull_len, it is likely
 107  * that the rest of the mblk will be short.
 108  *
 109  * This heuristic was decided upon after performance tests
 110  * indicated that anything more complex slowed down the main
 111  * code path.
 112  */
 113 #define MBLK_PULL_LEN 64
 114 uint32_t mblk_pull_len = MBLK_PULL_LEN;
 115 
 116 /*
 117  * The sgttyb_handling flag controls the handling of the old BSD
 118  * TIOCGETP, TIOCSETP, and TIOCSETN ioctls as follows:
 119  *
 120  * 0 - Emit no warnings at all and retain old, broken behavior.
 121  * 1 - Emit no warnings and silently handle new semantics.
 122  * 2 - Send cmn_err(CE_NOTE) when either TIOCSETP or TIOCSETN is used
 123  *     (once per system invocation).  Handle with new semantics.
 124  * 3 - Send SIGSYS when any TIOCGETP, TIOCSETP, or TIOCSETN call is
 125  *     made (so that offenders drop core and are easy to debug).
 126  *
 127  * The "new semantics" are that TIOCGETP returns B38400 for
 128  * sg_[io]speed if the corresponding value is over B38400, and that
 129  * TIOCSET[PN] accept B38400 in these cases to mean "retain current
 130  * bit rate."
 131  */
 132 int sgttyb_handling = 1;
 133 static boolean_t sgttyb_complaint;
 134 
 135 /* don't push drcompat module by default on Style-2 streams */
 136 static int push_drcompat = 0;
 137 
 138 /*
 139  * id value used to distinguish between different ioctl messages
 140  */
 141 static uint32_t ioc_id;
 142 
 143 static void putback(struct stdata *, queue_t *, mblk_t *, int);
 144 static void strcleanall(struct vnode *);
 145 static int strwsrv(queue_t *);
 146 static int strdocmd(struct stdata *, struct strcmd *, cred_t *);
 147 
 148 /*
 149  * qinit and module_info structures for stream head read and write queues
 150  */
 151 struct module_info strm_info = { 0, "strrhead", 0, INFPSZ, STRHIGH, STRLOW };
 152 struct module_info stwm_info = { 0, "strwhead", 0, 0, 0, 0 };
 153 struct qinit strdata = { strrput, NULL, NULL, NULL, NULL, &strm_info };
 154 struct qinit stwdata = { NULL, strwsrv, NULL, NULL, NULL, &stwm_info };
 155 struct module_info fiform_info = { 0, "fifostrrhead", 0, PIPE_BUF, FIFOHIWAT,
 156     FIFOLOWAT };
 157 struct module_info fifowm_info = { 0, "fifostrwhead", 0, 0, 0, 0 };
 158 struct qinit fifo_strdata = { strrput, NULL, NULL, NULL, NULL, &fiform_info };
 159 struct qinit fifo_stwdata = { NULL, strwsrv, NULL, NULL, NULL, &fifowm_info };
 160 
 161 extern kmutex_t strresources;   /* protects global resources */
 162 extern kmutex_t muxifier;       /* single-threads multiplexor creation */
 163 
 164 static boolean_t msghasdata(mblk_t *bp);
 165 #define msgnodata(bp) (!msghasdata(bp))
 166 
 167 /*
 168  * Stream head locking notes:
 169  *      There are four monitors associated with the stream head:
 170  *      1. v_stream monitor: in stropen() and strclose() v_lock
 171  *              is held while the association of vnode and stream
 172  *              head is established or tested for.
 173  *      2. open/close/push/pop monitor: sd_lock is held while each
 174  *              thread bids for exclusive access to this monitor
 175  *              for opening or closing a stream.  In addition, this
 176  *              monitor is entered during pushes and pops.  This
 177  *              guarantees that during plumbing operations there
 178  *              is only one thread trying to change the plumbing.
 179  *              Any other threads present in the stream are only
 180  *              using the plumbing.
 181  *      3. read/write monitor: in the case of read, a thread holds
 182  *              sd_lock while trying to get data from the stream
 183  *              head queue.  if there is none to fulfill a read
 184  *              request, it sets RSLEEP and calls cv_wait_sig() down
 185  *              in strwaitq() to await the arrival of new data.
 186  *              when new data arrives in strrput(), sd_lock is acquired
 187  *              before testing for RSLEEP and calling cv_broadcast().
 188  *              the behavior of strwrite(), strwsrv(), and WSLEEP
 189  *              mirror this.
 190  *      4. ioctl monitor: sd_lock is gotten to ensure that only one
 191  *              thread is doing an ioctl at a time.
 192  */
 193 
 194 static int
 195 push_mod(queue_t *qp, dev_t *devp, struct stdata *stp, const char *name,
 196     int anchor, cred_t *crp, uint_t anchor_zoneid)
 197 {
 198         int error;
 199         fmodsw_impl_t *fp;
 200 
 201         if (stp->sd_flag & (STRHUP|STRDERR|STWRERR)) {
 202                 error = (stp->sd_flag & STRHUP) ? ENXIO : EIO;
 203                 return (error);
 204         }
 205         if (stp->sd_pushcnt >= nstrpush) {
 206                 return (EINVAL);
 207         }
 208 
 209         if ((fp = fmodsw_find(name, FMODSW_HOLD | FMODSW_LOAD)) == NULL) {
 210                 stp->sd_flag |= STREOPENFAIL;
 211                 return (EINVAL);
 212         }
 213 
 214         /*
 215          * push new module and call its open routine via qattach
 216          */
 217         if ((error = qattach(qp, devp, 0, crp, fp, B_FALSE)) != 0)
 218                 return (error);
 219 
 220         /*
 221          * Check to see if caller wants a STREAMS anchor
 222          * put at this place in the stream, and add if so.
 223          */
 224         mutex_enter(&stp->sd_lock);
 225         if (anchor == stp->sd_pushcnt) {
 226                 stp->sd_anchor = stp->sd_pushcnt;
 227                 stp->sd_anchorzone = anchor_zoneid;
 228         }
 229         mutex_exit(&stp->sd_lock);
 230 
 231         return (0);
 232 }
 233 
 234 /*
 235  * Open a stream device.
 236  */
 237 int
 238 stropen(vnode_t *vp, dev_t *devp, int flag, cred_t *crp)
 239 {
 240         struct stdata *stp;
 241         queue_t *qp;
 242         int s;
 243         dev_t dummydev, savedev;
 244         struct autopush *ap;
 245         struct dlautopush dlap;
 246         int error = 0;
 247         ssize_t rmin, rmax;
 248         int cloneopen;
 249         queue_t *brq;
 250         major_t major;
 251         str_stack_t *ss;
 252         zoneid_t zoneid;
 253         uint_t anchor;
 254 
 255         /*
 256          * If the stream already exists, wait for any open in progress
 257          * to complete, then call the open function of each module and
 258          * driver in the stream.  Otherwise create the stream.
 259          */
 260         TRACE_1(TR_FAC_STREAMS_FR, TR_STROPEN, "stropen:%p", vp);
 261 retry:
 262         mutex_enter(&vp->v_lock);
 263         if ((stp = vp->v_stream) != NULL) {
 264 
 265                 /*
 266                  * Waiting for stream to be created to device
 267                  * due to another open.
 268                  */
 269                 mutex_exit(&vp->v_lock);
 270 
 271                 if (STRMATED(stp)) {
 272                         struct stdata *strmatep = stp->sd_mate;
 273 
 274                         STRLOCKMATES(stp);
 275                         if (strmatep->sd_flag & (STWOPEN|STRCLOSE|STRPLUMB)) {
 276                                 if (flag & (FNDELAY|FNONBLOCK)) {
 277                                         error = EAGAIN;
 278                                         mutex_exit(&strmatep->sd_lock);
 279                                         goto ckreturn;
 280                                 }
 281                                 mutex_exit(&stp->sd_lock);
 282                                 if (!cv_wait_sig(&strmatep->sd_monitor,
 283                                     &strmatep->sd_lock)) {
 284                                         error = EINTR;
 285                                         mutex_exit(&strmatep->sd_lock);
 286                                         mutex_enter(&stp->sd_lock);
 287                                         goto ckreturn;
 288                                 }
 289                                 mutex_exit(&strmatep->sd_lock);
 290                                 goto retry;
 291                         }
 292                         if (stp->sd_flag & (STWOPEN|STRCLOSE|STRPLUMB)) {
 293                                 if (flag & (FNDELAY|FNONBLOCK)) {
 294                                         error = EAGAIN;
 295                                         mutex_exit(&strmatep->sd_lock);
 296                                         goto ckreturn;
 297                                 }
 298                                 mutex_exit(&strmatep->sd_lock);
 299                                 if (!cv_wait_sig(&stp->sd_monitor,
 300                                     &stp->sd_lock)) {
 301                                         error = EINTR;
 302                                         goto ckreturn;
 303                                 }
 304                                 mutex_exit(&stp->sd_lock);
 305                                 goto retry;
 306                         }
 307 
 308                         if (stp->sd_flag & (STRDERR|STWRERR)) {
 309                                 error = EIO;
 310                                 mutex_exit(&strmatep->sd_lock);
 311                                 goto ckreturn;
 312                         }
 313 
 314                         stp->sd_flag |= STWOPEN;
 315                         STRUNLOCKMATES(stp);
 316                 } else {
 317                         mutex_enter(&stp->sd_lock);
 318                         if (stp->sd_flag & (STWOPEN|STRCLOSE|STRPLUMB)) {
 319                                 if (flag & (FNDELAY|FNONBLOCK)) {
 320                                         error = EAGAIN;
 321                                         goto ckreturn;
 322                                 }
 323                                 if (!cv_wait_sig(&stp->sd_monitor,
 324                                     &stp->sd_lock)) {
 325                                         error = EINTR;
 326                                         goto ckreturn;
 327                                 }
 328                                 mutex_exit(&stp->sd_lock);
 329                                 goto retry;  /* could be clone! */
 330                         }
 331 
 332                         if (stp->sd_flag & (STRDERR|STWRERR)) {
 333                                 error = EIO;
 334                                 goto ckreturn;
 335                         }
 336 
 337                         stp->sd_flag |= STWOPEN;
 338                         mutex_exit(&stp->sd_lock);
 339                 }
 340 
 341                 /*
 342                  * Open all modules and devices down stream to notify
 343                  * that another user is streaming.  For modules, set the
 344                  * last argument to MODOPEN and do not pass any open flags.
 345                  * Ignore dummydev since this is not the first open.
 346                  */
 347                 claimstr(stp->sd_wrq);
 348                 qp = stp->sd_wrq;
 349                 while (_SAMESTR(qp)) {
 350                         qp = qp->q_next;
 351                         if ((error = qreopen(_RD(qp), devp, flag, crp)) != 0)
 352                                 break;
 353                 }
 354                 releasestr(stp->sd_wrq);
 355                 mutex_enter(&stp->sd_lock);
 356                 stp->sd_flag &= ~(STRHUP|STWOPEN|STRDERR|STWRERR);
 357                 stp->sd_rerror = 0;
 358                 stp->sd_werror = 0;
 359 ckreturn:
 360                 cv_broadcast(&stp->sd_monitor);
 361                 mutex_exit(&stp->sd_lock);
 362                 return (error);
 363         }
 364 
 365         /*
 366          * This vnode isn't streaming.  SPECFS already
 367          * checked for multiple vnodes pointing to the
 368          * same stream, so create a stream to the driver.
 369          */
 370         qp = allocq();
 371         stp = shalloc(qp);
 372 
 373         /*
 374          * Initialize stream head.  shalloc() has given us
 375          * exclusive access, and we have the vnode locked;
 376          * we can do whatever we want with stp.
 377          */
 378         stp->sd_flag = STWOPEN;
 379         stp->sd_siglist = NULL;
 380         stp->sd_pollist.ph_list = NULL;
 381         stp->sd_sigflags = 0;
 382         stp->sd_mark = NULL;
 383         stp->sd_closetime = STRTIMOUT;
 384         stp->sd_sidp = NULL;
 385         stp->sd_pgidp = NULL;
 386         stp->sd_vnode = vp;
 387         stp->sd_rerror = 0;
 388         stp->sd_werror = 0;
 389         stp->sd_wroff = 0;
 390         stp->sd_tail = 0;
 391         stp->sd_iocblk = NULL;
 392         stp->sd_cmdblk = NULL;
 393         stp->sd_pushcnt = 0;
 394         stp->sd_qn_minpsz = 0;
 395         stp->sd_qn_maxpsz = INFPSZ - 1;      /* used to check for initialization */
 396         stp->sd_maxblk = INFPSZ;
 397         qp->q_ptr = _WR(qp)->q_ptr = stp;
 398         STREAM(qp) = STREAM(_WR(qp)) = stp;
 399         vp->v_stream = stp;
 400         mutex_exit(&vp->v_lock);
 401         if (vp->v_type == VFIFO) {
 402                 stp->sd_flag |= OLDNDELAY;
 403                 /*
 404                  * This means, both for pipes and fifos
 405                  * strwrite will send SIGPIPE if the other
 406                  * end is closed. For putmsg it depends
 407                  * on whether it is a XPG4_2 application
 408                  * or not
 409                  */
 410                 stp->sd_wput_opt = SW_SIGPIPE;
 411 
 412                 /* setq might sleep in kmem_alloc - avoid holding locks. */
 413                 setq(qp, &fifo_strdata, &fifo_stwdata, NULL, QMTSAFE,
 414                     SQ_CI|SQ_CO, B_FALSE);
 415 
 416                 set_qend(qp);
 417                 stp->sd_strtab = fifo_getinfo();
 418                 _WR(qp)->q_nfsrv = _WR(qp);
 419                 qp->q_nfsrv = qp;
 420                 /*
 421                  * Wake up others that are waiting for stream to be created.
 422                  */
 423                 mutex_enter(&stp->sd_lock);
 424                 /*
 425                  * nothing is be pushed on stream yet, so
 426                  * optimized stream head packetsizes are just that
 427                  * of the read queue
 428                  */
 429                 stp->sd_qn_minpsz = qp->q_minpsz;
 430                 stp->sd_qn_maxpsz = qp->q_maxpsz;
 431                 stp->sd_flag &= ~STWOPEN;
 432                 goto fifo_opendone;
 433         }
 434         /* setq might sleep in kmem_alloc - avoid holding locks. */
 435         setq(qp, &strdata, &stwdata, NULL, QMTSAFE, SQ_CI|SQ_CO, B_FALSE);
 436 
 437         set_qend(qp);
 438 
 439         /*
 440          * Open driver and create stream to it (via qattach).
 441          */
 442         savedev = *devp;
 443         cloneopen = (getmajor(*devp) == clone_major);
 444         if ((error = qattach(qp, devp, flag, crp, NULL, B_FALSE)) != 0) {
 445                 mutex_enter(&vp->v_lock);
 446                 vp->v_stream = NULL;
 447                 mutex_exit(&vp->v_lock);
 448                 mutex_enter(&stp->sd_lock);
 449                 cv_broadcast(&stp->sd_monitor);
 450                 mutex_exit(&stp->sd_lock);
 451                 freeq(_RD(qp));
 452                 shfree(stp);
 453                 return (error);
 454         }
 455         /*
 456          * Set sd_strtab after open in order to handle clonable drivers
 457          */
 458         stp->sd_strtab = STREAMSTAB(getmajor(*devp));
 459 
 460         /*
 461          * Historical note: dummydev used to be be prior to the initial
 462          * open (via qattach above), which made the value seen
 463          * inconsistent between an I_PUSH and an autopush of a module.
 464          */
 465         dummydev = *devp;
 466 
 467         /*
 468          * For clone open of old style (Q not associated) network driver,
 469          * push DRMODNAME module to handle DL_ATTACH/DL_DETACH
 470          */
 471         brq = _RD(_WR(qp)->q_next);
 472         major = getmajor(*devp);
 473         if (push_drcompat && cloneopen && NETWORK_DRV(major) &&
 474             ((brq->q_flag & _QASSOCIATED) == 0)) {
 475                 if (push_mod(qp, &dummydev, stp, DRMODNAME, 0, crp, 0) != 0)
 476                         cmn_err(CE_WARN, "cannot push " DRMODNAME
 477                             " streams module");
 478         }
 479 
 480         if (!NETWORK_DRV(major)) {
 481                 savedev = *devp;
 482         } else {
 483                 /*
 484                  * For network devices, process differently based on the
 485                  * return value from dld_autopush():
 486                  *
 487                  *   0: the passed-in device points to a GLDv3 datalink with
 488                  *   per-link autopush configuration; use that configuration
 489                  *   and ignore any per-driver autopush configuration.
 490                  *
 491                  *   1: the passed-in device points to a physical GLDv3
 492                  *   datalink without per-link autopush configuration.  The
 493                  *   passed in device was changed to refer to the actual
 494                  *   physical device (if it's not already); we use that new
 495                  *   device to look up any per-driver autopush configuration.
 496                  *
 497                  *   -1: neither of the above cases applied; use the initial
 498                  *   device to look up any per-driver autopush configuration.
 499                  */
 500                 switch (dld_autopush(&savedev, &dlap)) {
 501                 case 0:
 502                         zoneid = crgetzoneid(crp);
 503                         for (s = 0; s < dlap.dap_npush; s++) {
 504                                 error = push_mod(qp, &dummydev, stp,
 505                                     dlap.dap_aplist[s], dlap.dap_anchor, crp,
 506                                     zoneid);
 507                                 if (error != 0)
 508                                         break;
 509                         }
 510                         goto opendone;
 511                 case 1:
 512                         break;
 513                 case -1:
 514                         savedev = *devp;
 515                         break;
 516                 }
 517         }
 518         /*
 519          * Find the autopush configuration based on "savedev". Start with the
 520          * global zone. If not found check in the local zone.
 521          */
 522         zoneid = GLOBAL_ZONEID;
 523 retryap:
 524         ss = netstack_find_by_stackid(zoneid_to_netstackid(zoneid))->
 525             netstack_str;
 526         if ((ap = sad_ap_find_by_dev(savedev, ss)) == NULL) {
 527                 netstack_rele(ss->ss_netstack);
 528                 if (zoneid == GLOBAL_ZONEID) {
 529                         /*
 530                          * None found. Also look in the zone's autopush table.
 531                          */
 532                         zoneid = crgetzoneid(crp);
 533                         if (zoneid != GLOBAL_ZONEID)
 534                                 goto retryap;
 535                 }
 536                 goto opendone;
 537         }
 538         anchor = ap->ap_anchor;
 539         zoneid = crgetzoneid(crp);
 540         for (s = 0; s < ap->ap_npush; s++) {
 541                 error = push_mod(qp, &dummydev, stp, ap->ap_list[s],
 542                     anchor, crp, zoneid);
 543                 if (error != 0)
 544                         break;
 545         }
 546         sad_ap_rele(ap, ss);
 547         netstack_rele(ss->ss_netstack);
 548 
 549 opendone:
 550 
 551         /*
 552          * let specfs know that open failed part way through
 553          */
 554         if (error) {
 555                 mutex_enter(&stp->sd_lock);
 556                 stp->sd_flag |= STREOPENFAIL;
 557                 mutex_exit(&stp->sd_lock);
 558         }
 559 
 560         /*
 561          * Wake up others that are waiting for stream to be created.
 562          */
 563         mutex_enter(&stp->sd_lock);
 564         stp->sd_flag &= ~STWOPEN;
 565 
 566         /*
 567          * As a performance concern we are caching the values of
 568          * q_minpsz and q_maxpsz of the module below the stream
 569          * head in the stream head.
 570          */
 571         mutex_enter(QLOCK(stp->sd_wrq->q_next));
 572         rmin = stp->sd_wrq->q_next->q_minpsz;
 573         rmax = stp->sd_wrq->q_next->q_maxpsz;
 574         mutex_exit(QLOCK(stp->sd_wrq->q_next));
 575 
 576         /* do this processing here as a performance concern */
 577         if (strmsgsz != 0) {
 578                 if (rmax == INFPSZ)
 579                         rmax = strmsgsz;
 580                 else
 581                         rmax = MIN(strmsgsz, rmax);
 582         }
 583 
 584         mutex_enter(QLOCK(stp->sd_wrq));
 585         stp->sd_qn_minpsz = rmin;
 586         stp->sd_qn_maxpsz = rmax;
 587         mutex_exit(QLOCK(stp->sd_wrq));
 588 
 589 fifo_opendone:
 590         cv_broadcast(&stp->sd_monitor);
 591         mutex_exit(&stp->sd_lock);
 592         return (error);
 593 }
 594 
 595 static int strsink(queue_t *, mblk_t *);
 596 static struct qinit deadrend = {
 597         strsink, NULL, NULL, NULL, NULL, &strm_info, NULL
 598 };
 599 static struct qinit deadwend = {
 600         NULL, NULL, NULL, NULL, NULL, &stwm_info, NULL
 601 };
 602 
 603 /*
 604  * Close a stream.
 605  * This is called from closef() on the last close of an open stream.
 606  * Strclean() will already have removed the siglist and pollist
 607  * information, so all that remains is to remove all multiplexor links
 608  * for the stream, pop all the modules (and the driver), and free the
 609  * stream structure.
 610  */
 611 
 612 int
 613 strclose(struct vnode *vp, int flag, cred_t *crp)
 614 {
 615         struct stdata *stp;
 616         queue_t *qp;
 617         int rval;
 618         int freestp = 1;
 619         queue_t *rmq;
 620 
 621         TRACE_1(TR_FAC_STREAMS_FR,
 622             TR_STRCLOSE, "strclose:%p", vp);
 623         ASSERT(vp->v_stream);
 624 
 625         stp = vp->v_stream;
 626         ASSERT(!(stp->sd_flag & STPLEX));
 627         qp = stp->sd_wrq;
 628 
 629         /*
 630          * Needed so that strpoll will return non-zero for this fd.
 631          * Note that with POLLNOERR STRHUP does still cause POLLHUP.
 632          */
 633         mutex_enter(&stp->sd_lock);
 634         stp->sd_flag |= STRHUP;
 635         mutex_exit(&stp->sd_lock);
 636 
 637         /*
 638          * If the registered process or process group did not have an
 639          * open instance of this stream then strclean would not be
 640          * called. Thus at the time of closing all remaining siglist entries
 641          * are removed.
 642          */
 643         if (stp->sd_siglist != NULL)
 644                 strcleanall(vp);
 645 
 646         ASSERT(stp->sd_siglist == NULL);
 647         ASSERT(stp->sd_sigflags == 0);
 648 
 649         if (STRMATED(stp)) {
 650                 struct stdata *strmatep = stp->sd_mate;
 651                 int waited = 1;
 652 
 653                 STRLOCKMATES(stp);
 654                 while (waited) {
 655                         waited = 0;
 656                         while (stp->sd_flag & (STWOPEN|STRCLOSE|STRPLUMB)) {
 657                                 mutex_exit(&strmatep->sd_lock);
 658                                 cv_wait(&stp->sd_monitor, &stp->sd_lock);
 659                                 mutex_exit(&stp->sd_lock);
 660                                 STRLOCKMATES(stp);
 661                                 waited = 1;
 662                         }
 663                         while (strmatep->sd_flag &
 664                             (STWOPEN|STRCLOSE|STRPLUMB)) {
 665                                 mutex_exit(&stp->sd_lock);
 666                                 cv_wait(&strmatep->sd_monitor,
 667                                     &strmatep->sd_lock);
 668                                 mutex_exit(&strmatep->sd_lock);
 669                                 STRLOCKMATES(stp);
 670                                 waited = 1;
 671                         }
 672                 }
 673                 stp->sd_flag |= STRCLOSE;
 674                 STRUNLOCKMATES(stp);
 675         } else {
 676                 mutex_enter(&stp->sd_lock);
 677                 stp->sd_flag |= STRCLOSE;
 678                 mutex_exit(&stp->sd_lock);
 679         }
 680 
 681         ASSERT(qp->q_first == NULL); /* No more delayed write */
 682 
 683         /* Check if an I_LINK was ever done on this stream */
 684         if (stp->sd_flag & STRHASLINKS) {
 685                 netstack_t *ns;
 686                 str_stack_t *ss;
 687 
 688                 ns = netstack_find_by_cred(crp);
 689                 ASSERT(ns != NULL);
 690                 ss = ns->netstack_str;
 691                 ASSERT(ss != NULL);
 692 
 693                 (void) munlinkall(stp, LINKCLOSE|LINKNORMAL, crp, &rval, ss);
 694                 netstack_rele(ss->ss_netstack);
 695         }
 696 
 697         while (_SAMESTR(qp)) {
 698                 /*
 699                  * Holding sd_lock prevents q_next from changing in
 700                  * this stream.
 701                  */
 702                 mutex_enter(&stp->sd_lock);
 703                 if (!(flag & (FNDELAY|FNONBLOCK)) && (stp->sd_closetime > 0)) {
 704 
 705                         /*
 706                          * sleep until awakened by strwsrv() or timeout
 707                          */
 708                         for (;;) {
 709                                 mutex_enter(QLOCK(qp->q_next));
 710                                 if (!(qp->q_next->q_mblkcnt)) {
 711                                         mutex_exit(QLOCK(qp->q_next));
 712                                         break;
 713                                 }
 714                                 stp->sd_flag |= WSLEEP;
 715 
 716                                 /* ensure strwsrv gets enabled */
 717                                 qp->q_next->q_flag |= QWANTW;
 718                                 mutex_exit(QLOCK(qp->q_next));
 719                                 /* get out if we timed out or recv'd a signal */
 720                                 if (str_cv_wait(&qp->q_wait, &stp->sd_lock,
 721                                     stp->sd_closetime, 0) <= 0) {
 722                                         break;
 723                                 }
 724                         }
 725                         stp->sd_flag &= ~WSLEEP;
 726                 }
 727                 mutex_exit(&stp->sd_lock);
 728 
 729                 rmq = qp->q_next;
 730                 if (rmq->q_flag & QISDRV) {
 731                         ASSERT(!_SAMESTR(rmq));
 732                         wait_sq_svc(_RD(qp)->q_syncq);
 733                 }
 734 
 735                 qdetach(_RD(rmq), 1, flag, crp, B_FALSE);
 736         }
 737 
 738         /*
 739          * Since we call pollwakeup in close() now, the poll list should
 740          * be empty in most cases. The only exception is the layered devices
 741          * (e.g. the console drivers with redirection modules pushed on top
 742          * of it).  We have to do this after calling qdetach() because
 743          * the redirection module won't have torn down the console
 744          * redirection until after qdetach() has been invoked.
 745          */
 746         if (stp->sd_pollist.ph_list != NULL) {
 747                 pollwakeup(&stp->sd_pollist, POLLERR);
 748                 pollhead_clean(&stp->sd_pollist);
 749         }
 750         ASSERT(stp->sd_pollist.ph_list == NULL);
 751         ASSERT(stp->sd_sidp == NULL);
 752         ASSERT(stp->sd_pgidp == NULL);
 753 
 754         /* Prevent qenable from re-enabling the stream head queue */
 755         disable_svc(_RD(qp));
 756 
 757         /*
 758          * Wait until service procedure of each queue is
 759          * run, if QINSERVICE is set.
 760          */
 761         wait_svc(_RD(qp));
 762 
 763         /*
 764          * Now, flush both queues.
 765          */
 766         flushq(_RD(qp), FLUSHALL);
 767         flushq(qp, FLUSHALL);
 768 
 769         /*
 770          * If the write queue of the stream head is pointing to a
 771          * read queue, we have a twisted stream.  If the read queue
 772          * is alive, convert the stream head queues into a dead end.
 773          * If the read queue is dead, free the dead pair.
 774          */
 775         if (qp->q_next && !_SAMESTR(qp)) {
 776                 if (qp->q_next->q_qinfo == &deadrend) {       /* half-closed pipe */
 777                         flushq(qp->q_next, FLUSHALL); /* ensure no message */
 778                         shfree(qp->q_next->q_stream);
 779                         freeq(qp->q_next);
 780                         freeq(_RD(qp));
 781                 } else if (qp->q_next == _RD(qp)) {  /* fifo */
 782                         freeq(_RD(qp));
 783                 } else {                                /* pipe */
 784                         freestp = 0;
 785                         /*
 786                          * The q_info pointers are never accessed when
 787                          * SQLOCK is held.
 788                          */
 789                         ASSERT(qp->q_syncq == _RD(qp)->q_syncq);
 790                         mutex_enter(SQLOCK(qp->q_syncq));
 791                         qp->q_qinfo = &deadwend;
 792                         _RD(qp)->q_qinfo = &deadrend;
 793                         mutex_exit(SQLOCK(qp->q_syncq));
 794                 }
 795         } else {
 796                 freeq(_RD(qp)); /* free stream head queue pair */
 797         }
 798 
 799         mutex_enter(&vp->v_lock);
 800         if (stp->sd_iocblk) {
 801                 if (stp->sd_iocblk != (mblk_t *)-1) {
 802                         freemsg(stp->sd_iocblk);
 803                 }
 804                 stp->sd_iocblk = NULL;
 805         }
 806         stp->sd_vnode = NULL;
 807         vp->v_stream = NULL;
 808         mutex_exit(&vp->v_lock);
 809         mutex_enter(&stp->sd_lock);
 810         freemsg(stp->sd_cmdblk);
 811         stp->sd_cmdblk = NULL;
 812         stp->sd_flag &= ~STRCLOSE;
 813         cv_broadcast(&stp->sd_monitor);
 814         mutex_exit(&stp->sd_lock);
 815 
 816         if (freestp)
 817                 shfree(stp);
 818         return (0);
 819 }
 820 
 821 static int
 822 strsink(queue_t *q, mblk_t *bp)
 823 {
 824         struct copyresp *resp;
 825 
 826         switch (bp->b_datap->db_type) {
 827         case M_FLUSH:
 828                 if ((*bp->b_rptr & FLUSHW) && !(bp->b_flag & MSGNOLOOP)) {
 829                         *bp->b_rptr &= ~FLUSHR;
 830                         bp->b_flag |= MSGNOLOOP;
 831                         /*
 832                          * Protect against the driver passing up
 833                          * messages after it has done a qprocsoff.
 834                          */
 835                         if (_OTHERQ(q)->q_next == NULL)
 836                                 freemsg(bp);
 837                         else
 838                                 qreply(q, bp);
 839                 } else {
 840                         freemsg(bp);
 841                 }
 842                 break;
 843 
 844         case M_COPYIN:
 845         case M_COPYOUT:
 846                 if (bp->b_cont) {
 847                         freemsg(bp->b_cont);
 848                         bp->b_cont = NULL;
 849                 }
 850                 bp->b_datap->db_type = M_IOCDATA;
 851                 bp->b_wptr = bp->b_rptr + sizeof (struct copyresp);
 852                 resp = (struct copyresp *)bp->b_rptr;
 853                 resp->cp_rval = (caddr_t)1;  /* failure */
 854                 /*
 855                  * Protect against the driver passing up
 856                  * messages after it has done a qprocsoff.
 857                  */
 858                 if (_OTHERQ(q)->q_next == NULL)
 859                         freemsg(bp);
 860                 else
 861                         qreply(q, bp);
 862                 break;
 863 
 864         case M_IOCTL:
 865                 if (bp->b_cont) {
 866                         freemsg(bp->b_cont);
 867                         bp->b_cont = NULL;
 868                 }
 869                 bp->b_datap->db_type = M_IOCNAK;
 870                 /*
 871                  * Protect against the driver passing up
 872                  * messages after it has done a qprocsoff.
 873                  */
 874                 if (_OTHERQ(q)->q_next == NULL)
 875                         freemsg(bp);
 876                 else
 877                         qreply(q, bp);
 878                 break;
 879 
 880         default:
 881                 freemsg(bp);
 882                 break;
 883         }
 884 
 885         return (0);
 886 }
 887 
 888 /*
 889  * Clean up after a process when it closes a stream.  This is called
 890  * from closef for all closes, whereas strclose is called only for the
 891  * last close on a stream.  The siglist is scanned for entries for the
 892  * current process, and these are removed.
 893  */
 894 void
 895 strclean(struct vnode *vp)
 896 {
 897         strsig_t *ssp, *pssp, *tssp;
 898         stdata_t *stp;
 899         int update = 0;
 900 
 901         TRACE_1(TR_FAC_STREAMS_FR,
 902             TR_STRCLEAN, "strclean:%p", vp);
 903         stp = vp->v_stream;
 904         pssp = NULL;
 905         mutex_enter(&stp->sd_lock);
 906         ssp = stp->sd_siglist;
 907         while (ssp) {
 908                 if (ssp->ss_pidp == curproc->p_pidp) {
 909                         tssp = ssp->ss_next;
 910                         if (pssp)
 911                                 pssp->ss_next = tssp;
 912                         else
 913                                 stp->sd_siglist = tssp;
 914                         mutex_enter(&pidlock);
 915                         PID_RELE(ssp->ss_pidp);
 916                         mutex_exit(&pidlock);
 917                         kmem_free(ssp, sizeof (strsig_t));
 918                         update = 1;
 919                         ssp = tssp;
 920                 } else {
 921                         pssp = ssp;
 922                         ssp = ssp->ss_next;
 923                 }
 924         }
 925         if (update) {
 926                 stp->sd_sigflags = 0;
 927                 for (ssp = stp->sd_siglist; ssp; ssp = ssp->ss_next)
 928                         stp->sd_sigflags |= ssp->ss_events;
 929         }
 930         mutex_exit(&stp->sd_lock);
 931 }
 932 
 933 /*
 934  * Used on the last close to remove any remaining items on the siglist.
 935  * These could be present on the siglist due to I_ESETSIG calls that
 936  * use process groups or processed that do not have an open file descriptor
 937  * for this stream (Such entries would not be removed by strclean).
 938  */
 939 static void
 940 strcleanall(struct vnode *vp)
 941 {
 942         strsig_t *ssp, *nssp;
 943         stdata_t *stp;
 944 
 945         stp = vp->v_stream;
 946         mutex_enter(&stp->sd_lock);
 947         ssp = stp->sd_siglist;
 948         stp->sd_siglist = NULL;
 949         while (ssp) {
 950                 nssp = ssp->ss_next;
 951                 mutex_enter(&pidlock);
 952                 PID_RELE(ssp->ss_pidp);
 953                 mutex_exit(&pidlock);
 954                 kmem_free(ssp, sizeof (strsig_t));
 955                 ssp = nssp;
 956         }
 957         stp->sd_sigflags = 0;
 958         mutex_exit(&stp->sd_lock);
 959 }
 960 
 961 /*
 962  * Retrieve the next message from the logical stream head read queue
 963  * using either rwnext (if sync stream) or getq_noenab.
 964  * It is the callers responsibility to call qbackenable after
 965  * it is finished with the message. The caller should not call
 966  * qbackenable until after any putback calls to avoid spurious backenabling.
 967  */
 968 mblk_t *
 969 strget(struct stdata *stp, queue_t *q, struct uio *uiop, int first,
 970     int *errorp)
 971 {
 972         mblk_t *bp;
 973         int error;
 974         ssize_t rbytes = 0;
 975 
 976         /* Holding sd_lock prevents the read queue from changing  */
 977         ASSERT(MUTEX_HELD(&stp->sd_lock));
 978 
 979         if (uiop != NULL && stp->sd_struiordq != NULL &&
 980             q->q_first == NULL &&
 981             (!first || (stp->sd_wakeq & RSLEEP))) {
 982                 /*
 983                  * Stream supports rwnext() for the read side.
 984                  * If this is the first time we're called by e.g. strread
 985                  * only do the downcall if there is a deferred wakeup
 986                  * (registered in sd_wakeq).
 987                  */
 988                 struiod_t uiod;
 989                 struct iovec buf[IOV_MAX_STACK];
 990                 int iovlen = 0;
 991 
 992                 if (first)
 993                         stp->sd_wakeq &= ~RSLEEP;
 994 
 995                 if (uiop->uio_iovcnt > IOV_MAX_STACK) {
 996                         iovlen = uiop->uio_iovcnt * sizeof (iovec_t);
 997                         uiod.d_iov = kmem_alloc(iovlen, KM_SLEEP);
 998                 } else {
 999                         uiod.d_iov = buf;
1000                 }
1001 
1002                 (void) uiodup(uiop, &uiod.d_uio, uiod.d_iov, uiop->uio_iovcnt);
1003                 uiod.d_mp = 0;
1004                 /*
1005                  * Mark that a thread is in rwnext on the read side
1006                  * to prevent strrput from nacking ioctls immediately.
1007                  * When the last concurrent rwnext returns
1008                  * the ioctls are nack'ed.
1009                  */
1010                 ASSERT(MUTEX_HELD(&stp->sd_lock));
1011                 stp->sd_struiodnak++;
1012                 /*
1013                  * Note: rwnext will drop sd_lock.
1014                  */
1015                 error = rwnext(q, &uiod);
1016                 ASSERT(MUTEX_NOT_HELD(&stp->sd_lock));
1017                 mutex_enter(&stp->sd_lock);
1018                 stp->sd_struiodnak--;
1019                 while (stp->sd_struiodnak == 0 &&
1020                     ((bp = stp->sd_struionak) != NULL)) {
1021                         stp->sd_struionak = bp->b_next;
1022                         bp->b_next = NULL;
1023                         bp->b_datap->db_type = M_IOCNAK;
1024                         /*
1025                          * Protect against the driver passing up
1026                          * messages after it has done a qprocsoff.
1027                          */
1028                         if (_OTHERQ(q)->q_next == NULL)
1029                                 freemsg(bp);
1030                         else {
1031                                 mutex_exit(&stp->sd_lock);
1032                                 qreply(q, bp);
1033                                 mutex_enter(&stp->sd_lock);
1034                         }
1035                 }
1036                 ASSERT(MUTEX_HELD(&stp->sd_lock));
1037                 if (error == 0 || error == EWOULDBLOCK) {
1038                         if ((bp = uiod.d_mp) != NULL) {
1039                                 *errorp = 0;
1040                                 ASSERT(MUTEX_HELD(&stp->sd_lock));
1041                                 if (iovlen != 0)
1042                                         kmem_free(uiod.d_iov, iovlen);
1043                                 return (bp);
1044                         }
1045                         error = 0;
1046                 } else if (error == EINVAL) {
1047                         /*
1048                          * The stream plumbing must have
1049                          * changed while we were away, so
1050                          * just turn off rwnext()s.
1051                          */
1052                         error = 0;
1053                 } else if (error == EBUSY) {
1054                         /*
1055                          * The module might have data in transit using putnext
1056                          * Fall back on waiting + getq.
1057                          */
1058                         error = 0;
1059                 } else {
1060                         *errorp = error;
1061                         ASSERT(MUTEX_HELD(&stp->sd_lock));
1062                         if (iovlen != 0)
1063                                 kmem_free(uiod.d_iov, iovlen);
1064                         return (NULL);
1065                 }
1066 
1067                 if (iovlen != 0)
1068                         kmem_free(uiod.d_iov, iovlen);
1069 
1070                 /*
1071                  * Try a getq in case a rwnext() generated mblk
1072                  * has bubbled up via strrput().
1073                  */
1074         }
1075         *errorp = 0;
1076         ASSERT(MUTEX_HELD(&stp->sd_lock));
1077 
1078         /*
1079          * If we have a valid uio, try and use this as a guide for how
1080          * many bytes to retrieve from the queue via getq_noenab().
1081          * Doing this can avoid unneccesary counting of overlong
1082          * messages in putback(). We currently only do this for sockets
1083          * and only if there is no sd_rputdatafunc hook.
1084          *
1085          * The sd_rputdatafunc hook transforms the entire message
1086          * before any bytes in it can be given to a client. So, rbytes
1087          * must be 0 if there is a hook.
1088          */
1089         if ((uiop != NULL) && (stp->sd_vnode->v_type == VSOCK) &&
1090             (stp->sd_rputdatafunc == NULL))
1091                 rbytes = uiop->uio_resid;
1092 
1093         return (getq_noenab(q, rbytes));
1094 }
1095 
1096 /*
1097  * Copy out the message pointed to by `bp' into the uio pointed to by `uiop'.
1098  * If the message does not fit in the uio the remainder of it is returned;
1099  * otherwise NULL is returned.  Any embedded zero-length mblk_t's are
1100  * consumed, even if uio_resid reaches zero.  On error, `*errorp' is set to
1101  * the error code, the message is consumed, and NULL is returned.
1102  */
1103 static mblk_t *
1104 struiocopyout(mblk_t *bp, struct uio *uiop, int *errorp)
1105 {
1106         int error;
1107         ptrdiff_t n;
1108         mblk_t *nbp;
1109 
1110         ASSERT(bp->b_wptr >= bp->b_rptr);
1111 
1112         do {
1113                 if ((n = MIN(uiop->uio_resid, MBLKL(bp))) != 0) {
1114                         ASSERT(n > 0);
1115 
1116                         error = uiomove(bp->b_rptr, n, UIO_READ, uiop);
1117                         if (error != 0) {
1118                                 freemsg(bp);
1119                                 *errorp = error;
1120                                 return (NULL);
1121                         }
1122                 }
1123 
1124                 bp->b_rptr += n;
1125                 while (bp != NULL && (bp->b_rptr >= bp->b_wptr)) {
1126                         nbp = bp;
1127                         bp = bp->b_cont;
1128                         freeb(nbp);
1129                 }
1130         } while (bp != NULL && uiop->uio_resid > 0);
1131 
1132         *errorp = 0;
1133         return (bp);
1134 }
1135 
1136 /*
1137  * Read a stream according to the mode flags in sd_flag:
1138  *
1139  * (default mode)               - Byte stream, msg boundaries are ignored
1140  * RD_MSGDIS (msg discard)      - Read on msg boundaries and throw away
1141  *                              any data remaining in msg
1142  * RD_MSGNODIS (msg non-discard) - Read on msg boundaries and put back
1143  *                              any remaining data on head of read queue
1144  *
1145  * Consume readable messages on the front of the queue until
1146  * ttolwp(curthread)->lwp_count
1147  * is satisfied, the readable messages are exhausted, or a message
1148  * boundary is reached in a message mode.  If no data was read and
1149  * the stream was not opened with the NDELAY flag, block until data arrives.
1150  * Otherwise return the data read and update the count.
1151  *
1152  * In default mode a 0 length message signifies end-of-file and terminates
1153  * a read in progress.  The 0 length message is removed from the queue
1154  * only if it is the only message read (no data is read).
1155  *
1156  * An attempt to read an M_PROTO or M_PCPROTO message results in an
1157  * EBADMSG error return, unless either RD_PROTDAT or RD_PROTDIS are set.
1158  * If RD_PROTDAT is set, M_PROTO and M_PCPROTO messages are read as data.
1159  * If RD_PROTDIS is set, the M_PROTO and M_PCPROTO parts of the message
1160  * are unlinked from and M_DATA blocks in the message, the protos are
1161  * thrown away, and the data is read.
1162  */
1163 /* ARGSUSED */
1164 int
1165 strread(struct vnode *vp, struct uio *uiop, cred_t *crp)
1166 {
1167         struct stdata *stp;
1168         mblk_t *bp, *nbp;
1169         queue_t *q;
1170         int error = 0;
1171         uint_t old_sd_flag;
1172         int first;
1173         char rflg;
1174         uint_t mark;            /* Contains MSG*MARK and _LASTMARK */
1175 #define _LASTMARK       0x8000  /* Distinct from MSG*MARK */
1176         short delim;
1177         unsigned char pri = 0;
1178         char waitflag;
1179         unsigned char type;
1180 
1181         TRACE_1(TR_FAC_STREAMS_FR,
1182             TR_STRREAD_ENTER, "strread:%p", vp);
1183         ASSERT(vp->v_stream);
1184         stp = vp->v_stream;
1185 
1186         mutex_enter(&stp->sd_lock);
1187 
1188         if ((error = i_straccess(stp, JCREAD)) != 0) {
1189                 mutex_exit(&stp->sd_lock);
1190                 return (error);
1191         }
1192 
1193         if (stp->sd_flag & (STRDERR|STPLEX)) {
1194                 error = strgeterr(stp, STRDERR|STPLEX, 0);
1195                 if (error != 0) {
1196                         mutex_exit(&stp->sd_lock);
1197                         return (error);
1198                 }
1199         }
1200 
1201         /*
1202          * Loop terminates when uiop->uio_resid == 0.
1203          */
1204         rflg = 0;
1205         waitflag = READWAIT;
1206         q = _RD(stp->sd_wrq);
1207         for (;;) {
1208                 ASSERT(MUTEX_HELD(&stp->sd_lock));
1209                 old_sd_flag = stp->sd_flag;
1210                 mark = 0;
1211                 delim = 0;
1212                 first = 1;
1213                 while ((bp = strget(stp, q, uiop, first, &error)) == NULL) {
1214                         int done = 0;
1215 
1216                         ASSERT(MUTEX_HELD(&stp->sd_lock));
1217 
1218                         if (error != 0)
1219                                 goto oops;
1220 
1221                         if (stp->sd_flag & (STRHUP|STREOF)) {
1222                                 goto oops;
1223                         }
1224                         if (rflg && !(stp->sd_flag & STRDELIM)) {
1225                                 goto oops;
1226                         }
1227                         /*
1228                          * If a read(fd,buf,0) has been done, there is no
1229                          * need to sleep. We always have zero bytes to
1230                          * return.
1231                          */
1232                         if (uiop->uio_resid == 0) {
1233                                 goto oops;
1234                         }
1235 
1236                         qbackenable(q, 0);
1237 
1238                         TRACE_3(TR_FAC_STREAMS_FR, TR_STRREAD_WAIT,
1239                             "strread calls strwaitq:%p, %p, %p",
1240                             vp, uiop, crp);
1241                         if ((error = strwaitq(stp, waitflag, uiop->uio_resid,
1242                             uiop->uio_fmode, -1, &done)) != 0 || done) {
1243                                 TRACE_3(TR_FAC_STREAMS_FR, TR_STRREAD_DONE,
1244                                     "strread error or done:%p, %p, %p",
1245                                     vp, uiop, crp);
1246                                 if ((uiop->uio_fmode & FNDELAY) &&
1247                                     (stp->sd_flag & OLDNDELAY) &&
1248                                     (error == EAGAIN))
1249                                         error = 0;
1250                                 goto oops;
1251                         }
1252                         TRACE_3(TR_FAC_STREAMS_FR, TR_STRREAD_AWAKE,
1253                             "strread awakes:%p, %p, %p", vp, uiop, crp);
1254                         if ((error = i_straccess(stp, JCREAD)) != 0) {
1255                                 goto oops;
1256                         }
1257                         first = 0;
1258                 }
1259 
1260                 ASSERT(MUTEX_HELD(&stp->sd_lock));
1261                 ASSERT(bp);
1262                 pri = bp->b_band;
1263                 /*
1264                  * Extract any mark information. If the message is not
1265                  * completely consumed this information will be put in the mblk
1266                  * that is putback.
1267                  * If MSGMARKNEXT is set and the message is completely consumed
1268                  * the STRATMARK flag will be set below. Likewise, if
1269                  * MSGNOTMARKNEXT is set and the message is
1270                  * completely consumed STRNOTATMARK will be set.
1271                  *
1272                  * For some unknown reason strread only breaks the read at the
1273                  * last mark.
1274                  */
1275                 mark = bp->b_flag & (MSGMARK | MSGMARKNEXT | MSGNOTMARKNEXT);
1276                 ASSERT((mark & (MSGMARKNEXT|MSGNOTMARKNEXT)) !=
1277                     (MSGMARKNEXT|MSGNOTMARKNEXT));
1278                 if (mark != 0 && bp == stp->sd_mark) {
1279                         if (rflg) {
1280                                 putback(stp, q, bp, pri);
1281                                 goto oops;
1282                         }
1283                         mark |= _LASTMARK;
1284                         stp->sd_mark = NULL;
1285                 }
1286                 if ((stp->sd_flag & STRDELIM) && (bp->b_flag & MSGDELIM))
1287                         delim = 1;
1288                 mutex_exit(&stp->sd_lock);
1289 
1290                 if (STREAM_NEEDSERVICE(stp))
1291                         stream_runservice(stp);
1292 
1293                 type = bp->b_datap->db_type;
1294 
1295                 switch (type) {
1296 
1297                 case M_DATA:
1298 ismdata:
1299                         if (msgnodata(bp)) {
1300                                 if (mark || delim) {
1301                                         freemsg(bp);
1302                                 } else if (rflg) {
1303 
1304                                         /*
1305                                          * If already read data put zero
1306                                          * length message back on queue else
1307                                          * free msg and return 0.
1308                                          */
1309                                         bp->b_band = pri;
1310                                         mutex_enter(&stp->sd_lock);
1311                                         putback(stp, q, bp, pri);
1312                                         mutex_exit(&stp->sd_lock);
1313                                 } else {
1314                                         freemsg(bp);
1315                                 }
1316                                 error =  0;
1317                                 goto oops1;
1318                         }
1319 
1320                         rflg = 1;
1321                         waitflag |= NOINTR;
1322                         bp = struiocopyout(bp, uiop, &error);
1323                         if (error != 0)
1324                                 goto oops1;
1325 
1326                         mutex_enter(&stp->sd_lock);
1327                         if (bp) {
1328                                 /*
1329                                  * Have remaining data in message.
1330                                  * Free msg if in discard mode.
1331                                  */
1332                                 if (stp->sd_read_opt & RD_MSGDIS) {
1333                                         freemsg(bp);
1334                                 } else {
1335                                         bp->b_band = pri;
1336                                         if ((mark & _LASTMARK) &&
1337                                             (stp->sd_mark == NULL))
1338                                                 stp->sd_mark = bp;
1339                                         bp->b_flag |= mark & ~_LASTMARK;
1340                                         if (delim)
1341                                                 bp->b_flag |= MSGDELIM;
1342                                         if (msgnodata(bp))
1343                                                 freemsg(bp);
1344                                         else
1345                                                 putback(stp, q, bp, pri);
1346                                 }
1347                         } else {
1348                                 /*
1349                                  * Consumed the complete message.
1350                                  * Move the MSG*MARKNEXT information
1351                                  * to the stream head just in case
1352                                  * the read queue becomes empty.
1353                                  *
1354                                  * If the stream head was at the mark
1355                                  * (STRATMARK) before we dropped sd_lock above
1356                                  * and some data was consumed then we have
1357                                  * moved past the mark thus STRATMARK is
1358                                  * cleared. However, if a message arrived in
1359                                  * strrput during the copyout above causing
1360                                  * STRATMARK to be set we can not clear that
1361                                  * flag.
1362                                  */
1363                                 if (mark &
1364                                     (MSGMARKNEXT|MSGNOTMARKNEXT|MSGMARK)) {
1365                                         if (mark & MSGMARKNEXT) {
1366                                                 stp->sd_flag &= ~STRNOTATMARK;
1367                                                 stp->sd_flag |= STRATMARK;
1368                                         } else if (mark & MSGNOTMARKNEXT) {
1369                                                 stp->sd_flag &= ~STRATMARK;
1370                                                 stp->sd_flag |= STRNOTATMARK;
1371                                         } else {
1372                                                 stp->sd_flag &=
1373                                                     ~(STRATMARK|STRNOTATMARK);
1374                                         }
1375                                 } else if (rflg && (old_sd_flag & STRATMARK)) {
1376                                         stp->sd_flag &= ~STRATMARK;
1377                                 }
1378                         }
1379 
1380                         /*
1381                          * Check for signal messages at the front of the read
1382                          * queue and generate the signal(s) if appropriate.
1383                          * The only signal that can be on queue is M_SIG at
1384                          * this point.
1385                          */
1386                         while ((((bp = q->q_first)) != NULL) &&
1387                             (bp->b_datap->db_type == M_SIG)) {
1388                                 bp = getq_noenab(q, 0);
1389                                 /*
1390                                  * sd_lock is held so the content of the
1391                                  * read queue can not change.
1392                                  */
1393                                 ASSERT(bp != NULL && DB_TYPE(bp) == M_SIG);
1394                                 strsignal_nolock(stp, *bp->b_rptr, bp->b_band);
1395                                 mutex_exit(&stp->sd_lock);
1396                                 freemsg(bp);
1397                                 if (STREAM_NEEDSERVICE(stp))
1398                                         stream_runservice(stp);
1399                                 mutex_enter(&stp->sd_lock);
1400                         }
1401 
1402                         if ((uiop->uio_resid == 0) || (mark & _LASTMARK) ||
1403                             delim ||
1404                             (stp->sd_read_opt & (RD_MSGDIS|RD_MSGNODIS))) {
1405                                 goto oops;
1406                         }
1407                         continue;
1408 
1409                 case M_SIG:
1410                         strsignal(stp, *bp->b_rptr, (int32_t)bp->b_band);
1411                         freemsg(bp);
1412                         mutex_enter(&stp->sd_lock);
1413                         continue;
1414 
1415                 case M_PROTO:
1416                 case M_PCPROTO:
1417                         /*
1418                          * Only data messages are readable.
1419                          * Any others generate an error, unless
1420                          * RD_PROTDIS or RD_PROTDAT is set.
1421                          */
1422                         if (stp->sd_read_opt & RD_PROTDAT) {
1423                                 for (nbp = bp; nbp; nbp = nbp->b_next) {
1424                                         if ((nbp->b_datap->db_type ==
1425                                             M_PROTO) ||
1426                                             (nbp->b_datap->db_type ==
1427                                             M_PCPROTO)) {
1428                                                 nbp->b_datap->db_type = M_DATA;
1429                                         } else {
1430                                                 break;
1431                                         }
1432                                 }
1433                                 /*
1434                                  * clear stream head hi pri flag based on
1435                                  * first message
1436                                  */
1437                                 if (type == M_PCPROTO) {
1438                                         mutex_enter(&stp->sd_lock);
1439                                         stp->sd_flag &= ~STRPRI;
1440                                         mutex_exit(&stp->sd_lock);
1441                                 }
1442                                 goto ismdata;
1443                         } else if (stp->sd_read_opt & RD_PROTDIS) {
1444                                 /*
1445                                  * discard non-data messages
1446                                  */
1447                                 while (bp &&
1448                                     ((bp->b_datap->db_type == M_PROTO) ||
1449                                     (bp->b_datap->db_type == M_PCPROTO))) {
1450                                         nbp = unlinkb(bp);
1451                                         freeb(bp);
1452                                         bp = nbp;
1453                                 }
1454                                 /*
1455                                  * clear stream head hi pri flag based on
1456                                  * first message
1457                                  */
1458                                 if (type == M_PCPROTO) {
1459                                         mutex_enter(&stp->sd_lock);
1460                                         stp->sd_flag &= ~STRPRI;
1461                                         mutex_exit(&stp->sd_lock);
1462                                 }
1463                                 if (bp) {
1464                                         bp->b_band = pri;
1465                                         goto ismdata;
1466                                 } else {
1467                                         break;
1468                                 }
1469                         }
1470                         /* FALLTHRU */
1471                 case M_PASSFP:
1472                         if ((bp->b_datap->db_type == M_PASSFP) &&
1473                             (stp->sd_read_opt & RD_PROTDIS)) {
1474                                 freemsg(bp);
1475                                 break;
1476                         }
1477                         mutex_enter(&stp->sd_lock);
1478                         putback(stp, q, bp, pri);
1479                         mutex_exit(&stp->sd_lock);
1480                         if (rflg == 0)
1481                                 error = EBADMSG;
1482                         goto oops1;
1483 
1484                 default:
1485                         /*
1486                          * Garbage on stream head read queue.
1487                          */
1488                         cmn_err(CE_WARN, "bad %x found at stream head\n",
1489                             bp->b_datap->db_type);
1490                         freemsg(bp);
1491                         goto oops1;
1492                 }
1493                 mutex_enter(&stp->sd_lock);
1494         }
1495 oops:
1496         mutex_exit(&stp->sd_lock);
1497 oops1:
1498         qbackenable(q, pri);
1499         return (error);
1500 #undef  _LASTMARK
1501 }
1502 
1503 /*
1504  * Default processing of M_PROTO/M_PCPROTO messages.
1505  * Determine which wakeups and signals are needed.
1506  * This can be replaced by a user-specified procedure for kernel users
1507  * of STREAMS.
1508  */
1509 /* ARGSUSED */
1510 mblk_t *
1511 strrput_proto(vnode_t *vp, mblk_t *mp,
1512     strwakeup_t *wakeups, strsigset_t *firstmsgsigs,
1513     strsigset_t *allmsgsigs, strpollset_t *pollwakeups)
1514 {
1515         *wakeups = RSLEEP;
1516         *allmsgsigs = 0;
1517 
1518         switch (mp->b_datap->db_type) {
1519         case M_PROTO:
1520                 if (mp->b_band == 0) {
1521                         *firstmsgsigs = S_INPUT | S_RDNORM;
1522                         *pollwakeups = POLLIN | POLLRDNORM;
1523                 } else {
1524                         *firstmsgsigs = S_INPUT | S_RDBAND;
1525                         *pollwakeups = POLLIN | POLLRDBAND;
1526                 }
1527                 break;
1528         case M_PCPROTO:
1529                 *firstmsgsigs = S_HIPRI;
1530                 *pollwakeups = POLLPRI;
1531                 break;
1532         }
1533         return (mp);
1534 }
1535 
1536 /*
1537  * Default processing of everything but M_DATA, M_PROTO, M_PCPROTO and
1538  * M_PASSFP messages.
1539  * Determine which wakeups and signals are needed.
1540  * This can be replaced by a user-specified procedure for kernel users
1541  * of STREAMS.
1542  */
1543 /* ARGSUSED */
1544 mblk_t *
1545 strrput_misc(vnode_t *vp, mblk_t *mp,
1546     strwakeup_t *wakeups, strsigset_t *firstmsgsigs,
1547     strsigset_t *allmsgsigs, strpollset_t *pollwakeups)
1548 {
1549         *wakeups = 0;
1550         *firstmsgsigs = 0;
1551         *allmsgsigs = 0;
1552         *pollwakeups = 0;
1553         return (mp);
1554 }
1555 
1556 /*
1557  * Stream read put procedure.  Called from downstream driver/module
1558  * with messages for the stream head.  Data, protocol, and in-stream
1559  * signal messages are placed on the queue, others are handled directly.
1560  */
1561 int
1562 strrput(queue_t *q, mblk_t *bp)
1563 {
1564         struct stdata   *stp;
1565         ulong_t         rput_opt;
1566         strwakeup_t     wakeups;
1567         strsigset_t     firstmsgsigs;   /* Signals if first message on queue */
1568         strsigset_t     allmsgsigs;     /* Signals for all messages */
1569         strsigset_t     signals;        /* Signals events to generate */
1570         strpollset_t    pollwakeups;
1571         mblk_t          *nextbp;
1572         uchar_t         band = 0;
1573         int             hipri_sig;
1574 
1575         stp = (struct stdata *)q->q_ptr;
1576         /*
1577          * Use rput_opt for optimized access to the SR_ flags except
1578          * SR_POLLIN. That flag has to be checked under sd_lock since it
1579          * is modified by strpoll().
1580          */
1581         rput_opt = stp->sd_rput_opt;
1582 
1583         ASSERT(qclaimed(q));
1584         TRACE_2(TR_FAC_STREAMS_FR, TR_STRRPUT_ENTER,
1585             "strrput called with message type:q %p bp %p", q, bp);
1586 
1587         /*
1588          * Perform initial processing and pass to the parameterized functions.
1589          */
1590         ASSERT(bp->b_next == NULL);
1591 
1592         switch (bp->b_datap->db_type) {
1593         case M_DATA:
1594                 /*
1595                  * sockfs is the only consumer of STREOF and when it is set,
1596                  * it implies that the receiver is not interested in receiving
1597                  * any more data, hence the mblk is freed to prevent unnecessary
1598                  * message queueing at the stream head.
1599                  */
1600                 if (stp->sd_flag == STREOF) {
1601                         freemsg(bp);
1602                         return (0);
1603                 }
1604                 if ((rput_opt & SR_IGN_ZEROLEN) &&
1605                     bp->b_rptr == bp->b_wptr && msgnodata(bp)) {
1606                         /*
1607                          * Ignore zero-length M_DATA messages. These might be
1608                          * generated by some transports.
1609                          * The zero-length M_DATA messages, even if they
1610                          * are ignored, should effect the atmark tracking and
1611                          * should wake up a thread sleeping in strwaitmark.
1612                          */
1613                         mutex_enter(&stp->sd_lock);
1614                         if (bp->b_flag & MSGMARKNEXT) {
1615                                 /*
1616                                  * Record the position of the mark either
1617                                  * in q_last or in STRATMARK.
1618                                  */
1619                                 if (q->q_last != NULL) {
1620                                         q->q_last->b_flag &= ~MSGNOTMARKNEXT;
1621                                         q->q_last->b_flag |= MSGMARKNEXT;
1622                                 } else {
1623                                         stp->sd_flag &= ~STRNOTATMARK;
1624                                         stp->sd_flag |= STRATMARK;
1625                                 }
1626                         } else if (bp->b_flag & MSGNOTMARKNEXT) {
1627                                 /*
1628                                  * Record that this is not the position of
1629                                  * the mark either in q_last or in
1630                                  * STRNOTATMARK.
1631                                  */
1632                                 if (q->q_last != NULL) {
1633                                         q->q_last->b_flag &= ~MSGMARKNEXT;
1634                                         q->q_last->b_flag |= MSGNOTMARKNEXT;
1635                                 } else {
1636                                         stp->sd_flag &= ~STRATMARK;
1637                                         stp->sd_flag |= STRNOTATMARK;
1638                                 }
1639                         }
1640                         if (stp->sd_flag & RSLEEP) {
1641                                 stp->sd_flag &= ~RSLEEP;
1642                                 cv_broadcast(&q->q_wait);
1643                         }
1644                         mutex_exit(&stp->sd_lock);
1645                         freemsg(bp);
1646                         return (0);
1647                 }
1648                 wakeups = RSLEEP;
1649                 if (bp->b_band == 0) {
1650                         firstmsgsigs = S_INPUT | S_RDNORM;
1651                         pollwakeups = POLLIN | POLLRDNORM;
1652                 } else {
1653                         firstmsgsigs = S_INPUT | S_RDBAND;
1654                         pollwakeups = POLLIN | POLLRDBAND;
1655                 }
1656                 if (rput_opt & SR_SIGALLDATA)
1657                         allmsgsigs = firstmsgsigs;
1658                 else
1659                         allmsgsigs = 0;
1660 
1661                 mutex_enter(&stp->sd_lock);
1662                 if ((rput_opt & SR_CONSOL_DATA) &&
1663                     (q->q_last != NULL) &&
1664                     (bp->b_flag & (MSGMARK|MSGDELIM)) == 0) {
1665                         /*
1666                          * Consolidate an M_DATA message onto an M_DATA,
1667                          * M_PROTO, or M_PCPROTO by merging it with q_last.
1668                          * The consolidation does not take place if
1669                          * the old message is marked with either of the
1670                          * marks or the delim flag or if the new
1671                          * message is marked with MSGMARK. The MSGMARK
1672                          * check is needed to handle the odd semantics of
1673                          * MSGMARK where essentially the whole message
1674                          * is to be treated as marked.
1675                          * Carry any MSGMARKNEXT  and MSGNOTMARKNEXT from the
1676                          * new message to the front of the b_cont chain.
1677                          */
1678                         mblk_t *lbp = q->q_last;
1679                         unsigned char db_type = lbp->b_datap->db_type;
1680 
1681                         if ((db_type == M_DATA || db_type == M_PROTO ||
1682                             db_type == M_PCPROTO) &&
1683                             !(lbp->b_flag & (MSGDELIM|MSGMARK|MSGMARKNEXT))) {
1684                                 rmvq_noenab(q, lbp);
1685                                 /*
1686                                  * The first message in the b_cont list
1687                                  * tracks MSGMARKNEXT and MSGNOTMARKNEXT.
1688                                  * We need to handle the case where we
1689                                  * are appending:
1690                                  *
1691                                  * 1) a MSGMARKNEXT to a MSGNOTMARKNEXT.
1692                                  * 2) a MSGMARKNEXT to a plain message.
1693                                  * 3) a MSGNOTMARKNEXT to a plain message
1694                                  * 4) a MSGNOTMARKNEXT to a MSGNOTMARKNEXT
1695                                  *    message.
1696                                  *
1697                                  * Thus we never append a MSGMARKNEXT or
1698                                  * MSGNOTMARKNEXT to a MSGMARKNEXT message.
1699                                  */
1700                                 if (bp->b_flag & MSGMARKNEXT) {
1701                                         lbp->b_flag |= MSGMARKNEXT;
1702                                         lbp->b_flag &= ~MSGNOTMARKNEXT;
1703                                         bp->b_flag &= ~MSGMARKNEXT;
1704                                 } else if (bp->b_flag & MSGNOTMARKNEXT) {
1705                                         lbp->b_flag |= MSGNOTMARKNEXT;
1706                                         bp->b_flag &= ~MSGNOTMARKNEXT;
1707                                 }
1708 
1709                                 linkb(lbp, bp);
1710                                 bp = lbp;
1711                                 /*
1712                                  * The new message logically isn't the first
1713                                  * even though the q_first check below thinks
1714                                  * it is. Clear the firstmsgsigs to make it
1715                                  * not appear to be first.
1716                                  */
1717                                 firstmsgsigs = 0;
1718                         }
1719                 }
1720                 break;
1721 
1722         case M_PASSFP:
1723                 wakeups = RSLEEP;
1724                 allmsgsigs = 0;
1725                 if (bp->b_band == 0) {
1726                         firstmsgsigs = S_INPUT | S_RDNORM;
1727                         pollwakeups = POLLIN | POLLRDNORM;
1728                 } else {
1729                         firstmsgsigs = S_INPUT | S_RDBAND;
1730                         pollwakeups = POLLIN | POLLRDBAND;
1731                 }
1732                 mutex_enter(&stp->sd_lock);
1733                 break;
1734 
1735         case M_PROTO:
1736         case M_PCPROTO:
1737                 ASSERT(stp->sd_rprotofunc != NULL);
1738                 bp = (stp->sd_rprotofunc)(stp->sd_vnode, bp,
1739                     &wakeups, &firstmsgsigs, &allmsgsigs, &pollwakeups);
1740 #define ALLSIG  (S_INPUT|S_HIPRI|S_OUTPUT|S_MSG|S_ERROR|S_HANGUP|S_RDNORM|\
1741                 S_WRNORM|S_RDBAND|S_WRBAND|S_BANDURG)
1742 #define ALLPOLL (POLLIN|POLLPRI|POLLOUT|POLLRDNORM|POLLWRNORM|POLLRDBAND|\
1743                 POLLWRBAND)
1744 
1745                 ASSERT((wakeups & ~(RSLEEP|WSLEEP)) == 0);
1746                 ASSERT((firstmsgsigs & ~ALLSIG) == 0);
1747                 ASSERT((allmsgsigs & ~ALLSIG) == 0);
1748                 ASSERT((pollwakeups & ~ALLPOLL) == 0);
1749 
1750                 mutex_enter(&stp->sd_lock);
1751                 break;
1752 
1753         default:
1754                 ASSERT(stp->sd_rmiscfunc != NULL);
1755                 bp = (stp->sd_rmiscfunc)(stp->sd_vnode, bp,
1756                     &wakeups, &firstmsgsigs, &allmsgsigs, &pollwakeups);
1757                 ASSERT((wakeups & ~(RSLEEP|WSLEEP)) == 0);
1758                 ASSERT((firstmsgsigs & ~ALLSIG) == 0);
1759                 ASSERT((allmsgsigs & ~ALLSIG) == 0);
1760                 ASSERT((pollwakeups & ~ALLPOLL) == 0);
1761 #undef  ALLSIG
1762 #undef  ALLPOLL
1763                 mutex_enter(&stp->sd_lock);
1764                 break;
1765         }
1766         ASSERT(MUTEX_HELD(&stp->sd_lock));
1767 
1768         /* By default generate superset of signals */
1769         signals = (firstmsgsigs | allmsgsigs);
1770 
1771         /*
1772          * The  proto and misc functions can return multiple messages
1773          * as a b_next chain. Such messages are processed separately.
1774          */
1775 one_more:
1776         hipri_sig = 0;
1777         if (bp == NULL) {
1778                 nextbp = NULL;
1779         } else {
1780                 nextbp = bp->b_next;
1781                 bp->b_next = NULL;
1782 
1783                 switch (bp->b_datap->db_type) {
1784                 case M_PCPROTO:
1785                         /*
1786                          * Only one priority protocol message is allowed at the
1787                          * stream head at a time.
1788                          */
1789                         if (stp->sd_flag & STRPRI) {
1790                                 TRACE_0(TR_FAC_STREAMS_FR, TR_STRRPUT_PROTERR,
1791                                     "M_PCPROTO already at head");
1792                                 freemsg(bp);
1793                                 mutex_exit(&stp->sd_lock);
1794                                 goto done;
1795                         }
1796                         stp->sd_flag |= STRPRI;
1797                         hipri_sig = 1;
1798                         /* FALLTHRU */
1799                 case M_DATA:
1800                 case M_PROTO:
1801                 case M_PASSFP:
1802                         band = bp->b_band;
1803                         /*
1804                          * Marking doesn't work well when messages
1805                          * are marked in more than one band.  We only
1806                          * remember the last message received, even if
1807                          * it is placed on the queue ahead of other
1808                          * marked messages.
1809                          */
1810                         if (bp->b_flag & MSGMARK)
1811                                 stp->sd_mark = bp;
1812                         (void) putq(q, bp);
1813 
1814                         /*
1815                          * If message is a PCPROTO message, always use
1816                          * firstmsgsigs to determine if a signal should be
1817                          * sent as strrput is the only place to send
1818                          * signals for PCPROTO. Other messages are based on
1819                          * the STRGETINPROG flag. The flag determines if
1820                          * strrput or (k)strgetmsg will be responsible for
1821                          * sending the signals, in the firstmsgsigs case.
1822                          */
1823                         if ((hipri_sig == 1) ||
1824                             (((stp->sd_flag & STRGETINPROG) == 0) &&
1825                             (q->q_first == bp)))
1826                                 signals = (firstmsgsigs | allmsgsigs);
1827                         else
1828                                 signals = allmsgsigs;
1829                         break;
1830 
1831                 default:
1832                         mutex_exit(&stp->sd_lock);
1833                         (void) strrput_nondata(q, bp);
1834                         mutex_enter(&stp->sd_lock);
1835                         break;
1836                 }
1837         }
1838         ASSERT(MUTEX_HELD(&stp->sd_lock));
1839         /*
1840          * Wake sleeping read/getmsg and cancel deferred wakeup
1841          */
1842         if (wakeups & RSLEEP)
1843                 stp->sd_wakeq &= ~RSLEEP;
1844 
1845         wakeups &= stp->sd_flag;
1846         if (wakeups & RSLEEP) {
1847                 stp->sd_flag &= ~RSLEEP;
1848                 cv_broadcast(&q->q_wait);
1849         }
1850         if (wakeups & WSLEEP) {
1851                 stp->sd_flag &= ~WSLEEP;
1852                 cv_broadcast(&_WR(q)->q_wait);
1853         }
1854 
1855         if (pollwakeups != 0) {
1856                 if (pollwakeups == (POLLIN | POLLRDNORM)) {
1857                         /*
1858                          * Can't use rput_opt since it was not
1859                          * read when sd_lock was held and SR_POLLIN is changed
1860                          * by strpoll() under sd_lock.
1861                          */
1862                         if (!(stp->sd_rput_opt & SR_POLLIN))
1863                                 goto no_pollwake;
1864                         stp->sd_rput_opt &= ~SR_POLLIN;
1865                 }
1866                 mutex_exit(&stp->sd_lock);
1867                 pollwakeup(&stp->sd_pollist, pollwakeups);
1868                 mutex_enter(&stp->sd_lock);
1869         }
1870 no_pollwake:
1871 
1872         /*
1873          * strsendsig can handle multiple signals with a
1874          * single call.
1875          */
1876         if (stp->sd_sigflags & signals)
1877                 strsendsig(stp->sd_siglist, signals, band, 0);
1878         mutex_exit(&stp->sd_lock);
1879 
1880 
1881 done:
1882         if (nextbp == NULL)
1883                 return (0);
1884 
1885         /*
1886          * Any signals were handled the first time.
1887          * Wakeups and pollwakeups are redone to avoid any race
1888          * conditions - all the messages are not queued until the
1889          * last message has been processed by strrput.
1890          */
1891         bp = nextbp;
1892         signals = firstmsgsigs = allmsgsigs = 0;
1893         mutex_enter(&stp->sd_lock);
1894         goto one_more;
1895 }
1896 
1897 static void
1898 log_dupioc(queue_t *rq, mblk_t *bp)
1899 {
1900         queue_t *wq, *qp;
1901         char *modnames, *mnp, *dname;
1902         size_t maxmodstr;
1903         boolean_t islast;
1904 
1905         /*
1906          * Allocate a buffer large enough to hold the names of nstrpush modules
1907          * and one driver, with spaces between and NUL terminator.  If we can't
1908          * get memory, then we'll just log the driver name.
1909          */
1910         maxmodstr = nstrpush * (FMNAMESZ + 1);
1911         mnp = modnames = kmem_alloc(maxmodstr, KM_NOSLEEP);
1912 
1913         /* march down write side to print log message down to the driver */
1914         wq = WR(rq);
1915 
1916         /* make sure q_next doesn't shift around while we're grabbing data */
1917         claimstr(wq);
1918         qp = wq->q_next;
1919         do {
1920                 dname = Q2NAME(qp);
1921                 islast = !SAMESTR(qp) || qp->q_next == NULL;
1922                 if (modnames == NULL) {
1923                         /*
1924                          * If we don't have memory, then get the driver name in
1925                          * the log where we can see it.  Note that memory
1926                          * pressure is a possible cause of these sorts of bugs.
1927                          */
1928                         if (islast) {
1929                                 modnames = dname;
1930                                 maxmodstr = 0;
1931                         }
1932                 } else {
1933                         mnp += snprintf(mnp, FMNAMESZ + 1, "%s", dname);
1934                         if (!islast)
1935                                 *mnp++ = ' ';
1936                 }
1937                 qp = qp->q_next;
1938         } while (!islast);
1939         releasestr(wq);
1940         /* Cannot happen unless stream head is corrupt. */
1941         ASSERT(modnames != NULL);
1942         (void) strlog(rq->q_qinfo->qi_minfo->mi_idnum, 0, 1,
1943             SL_CONSOLE|SL_TRACE|SL_ERROR,
1944             "Warning: stream %p received duplicate %X M_IOC%s; module list: %s",
1945             rq->q_ptr, ((struct iocblk *)bp->b_rptr)->ioc_cmd,
1946             (DB_TYPE(bp) == M_IOCACK ? "ACK" : "NAK"), modnames);
1947         if (maxmodstr != 0)
1948                 kmem_free(modnames, maxmodstr);
1949 }
1950 
1951 int
1952 strrput_nondata(queue_t *q, mblk_t *bp)
1953 {
1954         struct stdata *stp;
1955         struct iocblk *iocbp;
1956         struct stroptions *sop;
1957         struct copyreq *reqp;
1958         struct copyresp *resp;
1959         unsigned char bpri;
1960         unsigned char  flushed_already = 0;
1961 
1962         stp = (struct stdata *)q->q_ptr;
1963 
1964         ASSERT(!(stp->sd_flag & STPLEX));
1965         ASSERT(qclaimed(q));
1966 
1967         switch (bp->b_datap->db_type) {
1968         case M_ERROR:
1969                 /*
1970                  * An error has occurred downstream, the errno is in the first
1971                  * bytes of the message.
1972                  */
1973                 if ((bp->b_wptr - bp->b_rptr) == 2) {     /* New flavor */
1974                         unsigned char rw = 0;
1975 
1976                         mutex_enter(&stp->sd_lock);
1977                         if (*bp->b_rptr != NOERROR) {        /* read error */
1978                                 if (*bp->b_rptr != 0) {
1979                                         if (stp->sd_flag & STRDERR)
1980                                                 flushed_already |= FLUSHR;
1981                                         stp->sd_flag |= STRDERR;
1982                                         rw |= FLUSHR;
1983                                 } else {
1984                                         stp->sd_flag &= ~STRDERR;
1985                                 }
1986                                 stp->sd_rerror = *bp->b_rptr;
1987                         }
1988                         bp->b_rptr++;
1989                         if (*bp->b_rptr != NOERROR) {        /* write error */
1990                                 if (*bp->b_rptr != 0) {
1991                                         if (stp->sd_flag & STWRERR)
1992                                                 flushed_already |= FLUSHW;
1993                                         stp->sd_flag |= STWRERR;
1994                                         rw |= FLUSHW;
1995                                 } else {
1996                                         stp->sd_flag &= ~STWRERR;
1997                                 }
1998                                 stp->sd_werror = *bp->b_rptr;
1999                         }
2000                         if (rw) {
2001                                 TRACE_2(TR_FAC_STREAMS_FR, TR_STRRPUT_WAKE,
2002                                     "strrput cv_broadcast:q %p, bp %p",
2003                                     q, bp);
2004                                 cv_broadcast(&q->q_wait); /* readers */
2005                                 cv_broadcast(&_WR(q)->q_wait); /* writers */
2006                                 cv_broadcast(&stp->sd_monitor); /* ioctllers */
2007 
2008                                 mutex_exit(&stp->sd_lock);
2009                                 pollwakeup(&stp->sd_pollist, POLLERR);
2010                                 mutex_enter(&stp->sd_lock);
2011 
2012                                 if (stp->sd_sigflags & S_ERROR)
2013                                         strsendsig(stp->sd_siglist, S_ERROR, 0,
2014                                             ((rw & FLUSHR) ? stp->sd_rerror :
2015                                             stp->sd_werror));
2016                                 mutex_exit(&stp->sd_lock);
2017                                 /*
2018                                  * Send the M_FLUSH only
2019                                  * for the first M_ERROR
2020                                  * message on the stream
2021                                  */
2022                                 if (flushed_already == rw) {
2023                                         freemsg(bp);
2024                                         return (0);
2025                                 }
2026 
2027                                 bp->b_datap->db_type = M_FLUSH;
2028                                 *bp->b_rptr = rw;
2029                                 bp->b_wptr = bp->b_rptr + 1;
2030                                 /*
2031                                  * Protect against the driver
2032                                  * passing up messages after
2033                                  * it has done a qprocsoff
2034                                  */
2035                                 if (_OTHERQ(q)->q_next == NULL)
2036                                         freemsg(bp);
2037                                 else
2038                                         qreply(q, bp);
2039                                 return (0);
2040                         } else
2041                                 mutex_exit(&stp->sd_lock);
2042                 } else if (*bp->b_rptr != 0) {               /* Old flavor */
2043                                 if (stp->sd_flag & (STRDERR|STWRERR))
2044                                         flushed_already = FLUSHRW;
2045                                 mutex_enter(&stp->sd_lock);
2046                                 stp->sd_flag |= (STRDERR|STWRERR);
2047                                 stp->sd_rerror = *bp->b_rptr;
2048                                 stp->sd_werror = *bp->b_rptr;
2049                                 TRACE_2(TR_FAC_STREAMS_FR,
2050                                     TR_STRRPUT_WAKE2,
2051                                     "strrput wakeup #2:q %p, bp %p", q, bp);
2052                                 cv_broadcast(&q->q_wait); /* the readers */
2053                                 cv_broadcast(&_WR(q)->q_wait); /* the writers */
2054                                 cv_broadcast(&stp->sd_monitor); /* ioctllers */
2055 
2056                                 mutex_exit(&stp->sd_lock);
2057                                 pollwakeup(&stp->sd_pollist, POLLERR);
2058                                 mutex_enter(&stp->sd_lock);
2059 
2060                                 if (stp->sd_sigflags & S_ERROR)
2061                                         strsendsig(stp->sd_siglist, S_ERROR, 0,
2062                                             (stp->sd_werror ? stp->sd_werror :
2063                                             stp->sd_rerror));
2064                                 mutex_exit(&stp->sd_lock);
2065 
2066                                 /*
2067                                  * Send the M_FLUSH only
2068                                  * for the first M_ERROR
2069                                  * message on the stream
2070                                  */
2071                                 if (flushed_already != FLUSHRW) {
2072                                         bp->b_datap->db_type = M_FLUSH;
2073                                         *bp->b_rptr = FLUSHRW;
2074                                         /*
2075                                          * Protect against the driver passing up
2076                                          * messages after it has done a
2077                                          * qprocsoff.
2078                                          */
2079                                 if (_OTHERQ(q)->q_next == NULL)
2080                                         freemsg(bp);
2081                                 else
2082                                         qreply(q, bp);
2083                                 return (0);
2084                                 }
2085                 }
2086                 freemsg(bp);
2087                 return (0);
2088 
2089         case M_HANGUP:
2090 
2091                 freemsg(bp);
2092                 mutex_enter(&stp->sd_lock);
2093                 stp->sd_werror = ENXIO;
2094                 stp->sd_flag |= STRHUP;
2095                 stp->sd_flag &= ~(WSLEEP|RSLEEP);
2096 
2097                 /*
2098                  * send signal if controlling tty
2099                  */
2100 
2101                 if (stp->sd_sidp) {
2102                         prsignal(stp->sd_sidp, SIGHUP);
2103                         if (stp->sd_sidp != stp->sd_pgidp)
2104                                 pgsignal(stp->sd_pgidp, SIGTSTP);
2105                 }
2106 
2107                 /*
2108                  * wake up read, write, and exception pollers and
2109                  * reset wakeup mechanism.
2110                  */
2111                 cv_broadcast(&q->q_wait);        /* the readers */
2112                 cv_broadcast(&_WR(q)->q_wait);   /* the writers */
2113                 cv_broadcast(&stp->sd_monitor);  /* the ioctllers */
2114                 strhup(stp);
2115                 mutex_exit(&stp->sd_lock);
2116                 return (0);
2117 
2118         case M_UNHANGUP:
2119                 freemsg(bp);
2120                 mutex_enter(&stp->sd_lock);
2121                 stp->sd_werror = 0;
2122                 stp->sd_flag &= ~STRHUP;
2123                 mutex_exit(&stp->sd_lock);
2124                 return (0);
2125 
2126         case M_SIG:
2127                 /*
2128                  * Someone downstream wants to post a signal.  The
2129                  * signal to post is contained in the first byte of the
2130                  * message.  If the message would go on the front of
2131                  * the queue, send a signal to the process group
2132                  * (if not SIGPOLL) or to the siglist processes
2133                  * (SIGPOLL).  If something is already on the queue,
2134                  * OR if we are delivering a delayed suspend (*sigh*
2135                  * another "tty" hack) and there's no one sleeping already,
2136                  * just enqueue the message.
2137                  */
2138                 mutex_enter(&stp->sd_lock);
2139                 if (q->q_first || (*bp->b_rptr == SIGTSTP &&
2140                     !(stp->sd_flag & RSLEEP))) {
2141                         (void) putq(q, bp);
2142                         mutex_exit(&stp->sd_lock);
2143                         return (0);
2144                 }
2145                 mutex_exit(&stp->sd_lock);
2146                 /* FALLTHRU */
2147 
2148         case M_PCSIG:
2149                 /*
2150                  * Don't enqueue, just post the signal.
2151                  */
2152                 strsignal(stp, *bp->b_rptr, 0L);
2153                 freemsg(bp);
2154                 return (0);
2155 
2156         case M_CMD:
2157                 if (MBLKL(bp) != sizeof (cmdblk_t)) {
2158                         freemsg(bp);
2159                         return (0);
2160                 }
2161 
2162                 mutex_enter(&stp->sd_lock);
2163                 if (stp->sd_flag & STRCMDWAIT) {
2164                         ASSERT(stp->sd_cmdblk == NULL);
2165                         stp->sd_cmdblk = bp;
2166                         cv_broadcast(&stp->sd_monitor);
2167                         mutex_exit(&stp->sd_lock);
2168                 } else {
2169                         mutex_exit(&stp->sd_lock);
2170                         freemsg(bp);
2171                 }
2172                 return (0);
2173 
2174         case M_FLUSH:
2175                 /*
2176                  * Flush queues.  The indication of which queues to flush
2177                  * is in the first byte of the message.  If the read queue
2178                  * is specified, then flush it.  If FLUSHBAND is set, just
2179                  * flush the band specified by the second byte of the message.
2180                  *
2181                  * If a module has issued a M_SETOPT to not flush hi
2182                  * priority messages off of the stream head, then pass this
2183                  * flag into the flushq code to preserve such messages.
2184                  */
2185 
2186                 if (*bp->b_rptr & FLUSHR) {
2187                         mutex_enter(&stp->sd_lock);
2188                         if (*bp->b_rptr & FLUSHBAND) {
2189                                 ASSERT((bp->b_wptr - bp->b_rptr) >= 2);
2190                                 flushband(q, *(bp->b_rptr + 1), FLUSHALL);
2191                         } else
2192                                 flushq_common(q, FLUSHALL,
2193                                     stp->sd_read_opt & RFLUSHPCPROT);
2194                         if ((q->q_first == NULL) ||
2195                             (q->q_first->b_datap->db_type < QPCTL))
2196                                 stp->sd_flag &= ~STRPRI;
2197                         else {
2198                                 ASSERT(stp->sd_flag & STRPRI);
2199                         }
2200                         mutex_exit(&stp->sd_lock);
2201                 }
2202                 if ((*bp->b_rptr & FLUSHW) && !(bp->b_flag & MSGNOLOOP)) {
2203                         *bp->b_rptr &= ~FLUSHR;
2204                         bp->b_flag |= MSGNOLOOP;
2205                         /*
2206                          * Protect against the driver passing up
2207                          * messages after it has done a qprocsoff.
2208                          */
2209                         if (_OTHERQ(q)->q_next == NULL)
2210                                 freemsg(bp);
2211                         else
2212                                 qreply(q, bp);
2213                         return (0);
2214                 }
2215                 freemsg(bp);
2216                 return (0);
2217 
2218         case M_IOCACK:
2219         case M_IOCNAK:
2220                 iocbp = (struct iocblk *)bp->b_rptr;
2221                 /*
2222                  * If not waiting for ACK or NAK then just free msg.
2223                  * If incorrect id sequence number then just free msg.
2224                  * If already have ACK or NAK for user then this is a
2225                  *    duplicate, display a warning and free the msg.
2226                  */
2227                 mutex_enter(&stp->sd_lock);
2228                 if ((stp->sd_flag & IOCWAIT) == 0 || stp->sd_iocblk ||
2229                     (stp->sd_iocid != iocbp->ioc_id)) {
2230                         /*
2231                          * If the ACK/NAK is a dup, display a message
2232                          * Dup is when sd_iocid == ioc_id, and
2233                          * sd_iocblk == <valid ptr> or -1 (the former
2234                          * is when an ioctl has been put on the stream
2235                          * head, but has not yet been consumed, the
2236                          * later is when it has been consumed).
2237                          */
2238                         if ((stp->sd_iocid == iocbp->ioc_id) &&
2239                             (stp->sd_iocblk != NULL)) {
2240                                 log_dupioc(q, bp);
2241                         }
2242                         freemsg(bp);
2243                         mutex_exit(&stp->sd_lock);
2244                         return (0);
2245                 }
2246 
2247                 /*
2248                  * Assign ACK or NAK to user and wake up.
2249                  */
2250                 stp->sd_iocblk = bp;
2251                 cv_broadcast(&stp->sd_monitor);
2252                 mutex_exit(&stp->sd_lock);
2253                 return (0);
2254 
2255         case M_COPYIN:
2256         case M_COPYOUT:
2257                 reqp = (struct copyreq *)bp->b_rptr;
2258 
2259                 /*
2260                  * If not waiting for ACK or NAK then just fail request.
2261                  * If already have ACK, NAK, or copy request, then just
2262                  * fail request.
2263                  * If incorrect id sequence number then just fail request.
2264                  */
2265                 mutex_enter(&stp->sd_lock);
2266                 if ((stp->sd_flag & IOCWAIT) == 0 || stp->sd_iocblk ||
2267                     (stp->sd_iocid != reqp->cq_id)) {
2268                         if (bp->b_cont) {
2269                                 freemsg(bp->b_cont);
2270                                 bp->b_cont = NULL;
2271                         }
2272                         bp->b_datap->db_type = M_IOCDATA;
2273                         bp->b_wptr = bp->b_rptr + sizeof (struct copyresp);
2274                         resp = (struct copyresp *)bp->b_rptr;
2275                         resp->cp_rval = (caddr_t)1;  /* failure */
2276                         mutex_exit(&stp->sd_lock);
2277                         putnext(stp->sd_wrq, bp);
2278                         return (0);
2279                 }
2280 
2281                 /*
2282                  * Assign copy request to user and wake up.
2283                  */
2284                 stp->sd_iocblk = bp;
2285                 cv_broadcast(&stp->sd_monitor);
2286                 mutex_exit(&stp->sd_lock);
2287                 return (0);
2288 
2289         case M_SETOPTS:
2290                 /*
2291                  * Set stream head options (read option, write offset,
2292                  * min/max packet size, and/or high/low water marks for
2293                  * the read side only).
2294                  */
2295 
2296                 bpri = 0;
2297                 sop = (struct stroptions *)bp->b_rptr;
2298                 mutex_enter(&stp->sd_lock);
2299                 if (sop->so_flags & SO_READOPT) {
2300                         switch (sop->so_readopt & RMODEMASK) {
2301                         case RNORM:
2302                                 stp->sd_read_opt &= ~(RD_MSGDIS | RD_MSGNODIS);
2303                                 break;
2304 
2305                         case RMSGD:
2306                                 stp->sd_read_opt =
2307                                     ((stp->sd_read_opt & ~RD_MSGNODIS) |
2308                                     RD_MSGDIS);
2309                                 break;
2310 
2311                         case RMSGN:
2312                                 stp->sd_read_opt =
2313                                     ((stp->sd_read_opt & ~RD_MSGDIS) |
2314                                     RD_MSGNODIS);
2315                                 break;
2316                         }
2317                         switch (sop->so_readopt & RPROTMASK) {
2318                         case RPROTNORM:
2319                                 stp->sd_read_opt &= ~(RD_PROTDAT | RD_PROTDIS);
2320                                 break;
2321 
2322                         case RPROTDAT:
2323                                 stp->sd_read_opt =
2324                                     ((stp->sd_read_opt & ~RD_PROTDIS) |
2325                                     RD_PROTDAT);
2326                                 break;
2327 
2328                         case RPROTDIS:
2329                                 stp->sd_read_opt =
2330                                     ((stp->sd_read_opt & ~RD_PROTDAT) |
2331                                     RD_PROTDIS);
2332                                 break;
2333                         }
2334                         switch (sop->so_readopt & RFLUSHMASK) {
2335                         case RFLUSHPCPROT:
2336                                 /*
2337                                  * This sets the stream head to NOT flush
2338                                  * M_PCPROTO messages.
2339                                  */
2340                                 stp->sd_read_opt |= RFLUSHPCPROT;
2341                                 break;
2342                         }
2343                 }
2344                 if (sop->so_flags & SO_ERROPT) {
2345                         switch (sop->so_erropt & RERRMASK) {
2346                         case RERRNORM:
2347                                 stp->sd_flag &= ~STRDERRNONPERSIST;
2348                                 break;
2349                         case RERRNONPERSIST:
2350                                 stp->sd_flag |= STRDERRNONPERSIST;
2351                                 break;
2352                         }
2353                         switch (sop->so_erropt & WERRMASK) {
2354                         case WERRNORM:
2355                                 stp->sd_flag &= ~STWRERRNONPERSIST;
2356                                 break;
2357                         case WERRNONPERSIST:
2358                                 stp->sd_flag |= STWRERRNONPERSIST;
2359                                 break;
2360                         }
2361                 }
2362                 if (sop->so_flags & SO_COPYOPT) {
2363                         if (sop->so_copyopt & ZCVMSAFE) {
2364                                 stp->sd_copyflag |= STZCVMSAFE;
2365                                 stp->sd_copyflag &= ~STZCVMUNSAFE;
2366                         } else if (sop->so_copyopt & ZCVMUNSAFE) {
2367                                 stp->sd_copyflag |= STZCVMUNSAFE;
2368                                 stp->sd_copyflag &= ~STZCVMSAFE;
2369                         }
2370 
2371                         if (sop->so_copyopt & COPYCACHED) {
2372                                 stp->sd_copyflag |= STRCOPYCACHED;
2373                         }
2374                 }
2375                 if (sop->so_flags & SO_WROFF)
2376                         stp->sd_wroff = sop->so_wroff;
2377                 if (sop->so_flags & SO_TAIL)
2378                         stp->sd_tail = sop->so_tail;
2379                 if (sop->so_flags & SO_MINPSZ)
2380                         q->q_minpsz = sop->so_minpsz;
2381                 if (sop->so_flags & SO_MAXPSZ)
2382                         q->q_maxpsz = sop->so_maxpsz;
2383                 if (sop->so_flags & SO_MAXBLK)
2384                         stp->sd_maxblk = sop->so_maxblk;
2385                 if (sop->so_flags & SO_HIWAT) {
2386                         if (sop->so_flags & SO_BAND) {
2387                                 if (strqset(q, QHIWAT,
2388                                     sop->so_band, sop->so_hiwat)) {
2389                                         cmn_err(CE_WARN, "strrput: could not "
2390                                             "allocate qband\n");
2391                                 } else {
2392                                         bpri = sop->so_band;
2393                                 }
2394                         } else {
2395                                 q->q_hiwat = sop->so_hiwat;
2396                         }
2397                 }
2398                 if (sop->so_flags & SO_LOWAT) {
2399                         if (sop->so_flags & SO_BAND) {
2400                                 if (strqset(q, QLOWAT,
2401                                     sop->so_band, sop->so_lowat)) {
2402                                         cmn_err(CE_WARN, "strrput: could not "
2403                                             "allocate qband\n");
2404                                 } else {
2405                                         bpri = sop->so_band;
2406                                 }
2407                         } else {
2408                                 q->q_lowat = sop->so_lowat;
2409                         }
2410                 }
2411                 if (sop->so_flags & SO_MREADON)
2412                         stp->sd_flag |= SNDMREAD;
2413                 if (sop->so_flags & SO_MREADOFF)
2414                         stp->sd_flag &= ~SNDMREAD;
2415                 if (sop->so_flags & SO_NDELON)
2416                         stp->sd_flag |= OLDNDELAY;
2417                 if (sop->so_flags & SO_NDELOFF)
2418                         stp->sd_flag &= ~OLDNDELAY;
2419                 if (sop->so_flags & SO_ISTTY)
2420                         stp->sd_flag |= STRISTTY;
2421                 if (sop->so_flags & SO_ISNTTY)
2422                         stp->sd_flag &= ~STRISTTY;
2423                 if (sop->so_flags & SO_TOSTOP)
2424                         stp->sd_flag |= STRTOSTOP;
2425                 if (sop->so_flags & SO_TONSTOP)
2426                         stp->sd_flag &= ~STRTOSTOP;
2427                 if (sop->so_flags & SO_DELIM)
2428                         stp->sd_flag |= STRDELIM;
2429                 if (sop->so_flags & SO_NODELIM)
2430                         stp->sd_flag &= ~STRDELIM;
2431 
2432                 mutex_exit(&stp->sd_lock);
2433                 freemsg(bp);
2434 
2435                 /* Check backenable in case the water marks changed */
2436                 qbackenable(q, bpri);
2437                 return (0);
2438 
2439         /*
2440          * The following set of cases deal with situations where two stream
2441          * heads are connected to each other (twisted streams).  These messages
2442          * have no meaning at the stream head.
2443          */
2444         case M_BREAK:
2445         case M_CTL:
2446         case M_DELAY:
2447         case M_START:
2448         case M_STOP:
2449         case M_IOCDATA:
2450         case M_STARTI:
2451         case M_STOPI:
2452                 freemsg(bp);
2453                 return (0);
2454 
2455         case M_IOCTL:
2456                 /*
2457                  * Always NAK this condition
2458                  * (makes no sense)
2459                  * If there is one or more threads in the read side
2460                  * rwnext we have to defer the nacking until that thread
2461                  * returns (in strget).
2462                  */
2463                 mutex_enter(&stp->sd_lock);
2464                 if (stp->sd_struiodnak != 0) {
2465                         /*
2466                          * Defer NAK to the streamhead. Queue at the end
2467                          * the list.
2468                          */
2469                         mblk_t *mp = stp->sd_struionak;
2470 
2471                         while (mp && mp->b_next)
2472                                 mp = mp->b_next;
2473                         if (mp)
2474                                 mp->b_next = bp;
2475                         else
2476                                 stp->sd_struionak = bp;
2477                         bp->b_next = NULL;
2478                         mutex_exit(&stp->sd_lock);
2479                         return (0);
2480                 }
2481                 mutex_exit(&stp->sd_lock);
2482 
2483                 bp->b_datap->db_type = M_IOCNAK;
2484                 /*
2485                  * Protect against the driver passing up
2486                  * messages after it has done a qprocsoff.
2487                  */
2488                 if (_OTHERQ(q)->q_next == NULL)
2489                         freemsg(bp);
2490                 else
2491                         qreply(q, bp);
2492                 return (0);
2493 
2494         default:
2495 #ifdef DEBUG
2496                 cmn_err(CE_WARN,
2497                     "bad message type %x received at stream head\n",
2498                     bp->b_datap->db_type);
2499 #endif
2500                 freemsg(bp);
2501                 return (0);
2502         }
2503 
2504         /* NOTREACHED */
2505 }
2506 
2507 /*
2508  * Check if the stream pointed to by `stp' can be written to, and return an
2509  * error code if not.  If `eiohup' is set, then return EIO if STRHUP is set.
2510  * If `sigpipeok' is set and the SW_SIGPIPE option is enabled on the stream,
2511  * then always return EPIPE and send a SIGPIPE to the invoking thread.
2512  */
2513 static int
2514 strwriteable(struct stdata *stp, boolean_t eiohup, boolean_t sigpipeok)
2515 {
2516         int error;
2517 
2518         ASSERT(MUTEX_HELD(&stp->sd_lock));
2519 
2520         /*
2521          * For modem support, POSIX states that on writes, EIO should
2522          * be returned if the stream has been hung up.
2523          */
2524         if (eiohup && (stp->sd_flag & (STPLEX|STRHUP)) == STRHUP)
2525                 error = EIO;
2526         else
2527                 error = strgeterr(stp, STRHUP|STPLEX|STWRERR, 0);
2528 
2529         if (error != 0) {
2530                 if (!(stp->sd_flag & STPLEX) &&
2531                     (stp->sd_wput_opt & SW_SIGPIPE) && sigpipeok) {
2532                         tsignal(curthread, SIGPIPE);
2533                         error = EPIPE;
2534                 }
2535         }
2536 
2537         return (error);
2538 }
2539 
2540 /*
2541  * Copyin and send data down a stream.
2542  * The caller will allocate and copyin any control part that precedes the
2543  * message and pass that in as mctl.
2544  *
2545  * Caller should *not* hold sd_lock.
2546  * When EWOULDBLOCK is returned the caller has to redo the canputnext
2547  * under sd_lock in order to avoid missing a backenabling wakeup.
2548  *
2549  * Use iosize = -1 to not send any M_DATA. iosize = 0 sends zero-length M_DATA.
2550  *
2551  * Set MSG_IGNFLOW in flags to ignore flow control for hipri messages.
2552  * For sync streams we can only ignore flow control by reverting to using
2553  * putnext.
2554  *
2555  * If sd_maxblk is less than *iosize this routine might return without
2556  * transferring all of *iosize. In all cases, on return *iosize will contain
2557  * the amount of data that was transferred.
2558  */
2559 static int
2560 strput(struct stdata *stp, mblk_t *mctl, struct uio *uiop, ssize_t *iosize,
2561     int b_flag, int pri, int flags)
2562 {
2563         struiod_t uiod;
2564         struct iovec buf[IOV_MAX_STACK];
2565         int iovlen = 0;
2566         mblk_t *mp;
2567         queue_t *wqp = stp->sd_wrq;
2568         int error = 0;
2569         ssize_t count = *iosize;
2570 
2571         ASSERT(MUTEX_NOT_HELD(&stp->sd_lock));
2572 
2573         if (uiop != NULL && count >= 0)
2574                 flags |= stp->sd_struiowrq ? STRUIO_POSTPONE : 0;
2575 
2576         if (!(flags & STRUIO_POSTPONE)) {
2577                 /*
2578                  * Use regular canputnext, strmakedata, putnext sequence.
2579                  */
2580                 if (pri == 0) {
2581                         if (!canputnext(wqp) && !(flags & MSG_IGNFLOW)) {
2582                                 freemsg(mctl);
2583                                 return (EWOULDBLOCK);
2584                         }
2585                 } else {
2586                         if (!(flags & MSG_IGNFLOW) && !bcanputnext(wqp, pri)) {
2587                                 freemsg(mctl);
2588                                 return (EWOULDBLOCK);
2589                         }
2590                 }
2591 
2592                 if ((error = strmakedata(iosize, uiop, stp, flags,
2593                     &mp)) != 0) {
2594                         freemsg(mctl);
2595                         /*
2596                          * need to change return code to ENOMEM
2597                          * so that this is not confused with
2598                          * flow control, EAGAIN.
2599                          */
2600 
2601                         if (error == EAGAIN)
2602                                 return (ENOMEM);
2603                         else
2604                                 return (error);
2605                 }
2606                 if (mctl != NULL) {
2607                         if (mctl->b_cont == NULL)
2608                                 mctl->b_cont = mp;
2609                         else if (mp != NULL)
2610                                 linkb(mctl, mp);
2611                         mp = mctl;
2612                 } else if (mp == NULL)
2613                         return (0);
2614 
2615                 mp->b_flag |= b_flag;
2616                 mp->b_band = (uchar_t)pri;
2617 
2618                 if (flags & MSG_IGNFLOW) {
2619                         /*
2620                          * XXX Hack: Don't get stuck running service
2621                          * procedures. This is needed for sockfs when
2622                          * sending the unbind message out of the rput
2623                          * procedure - we don't want a put procedure
2624                          * to run service procedures.
2625                          */
2626                         putnext(wqp, mp);
2627                 } else {
2628                         stream_willservice(stp);
2629                         putnext(wqp, mp);
2630                         stream_runservice(stp);
2631                 }
2632                 return (0);
2633         }
2634         /*
2635          * Stream supports rwnext() for the write side.
2636          */
2637         if ((error = strmakedata(iosize, uiop, stp, flags, &mp)) != 0) {
2638                 freemsg(mctl);
2639                 /*
2640                  * map EAGAIN to ENOMEM since EAGAIN means "flow controlled".
2641                  */
2642                 return (error == EAGAIN ? ENOMEM : error);
2643         }
2644         if (mctl != NULL) {
2645                 if (mctl->b_cont == NULL)
2646                         mctl->b_cont = mp;
2647                 else if (mp != NULL)
2648                         linkb(mctl, mp);
2649                 mp = mctl;
2650         } else if (mp == NULL) {
2651                 return (0);
2652         }
2653 
2654         mp->b_flag |= b_flag;
2655         mp->b_band = (uchar_t)pri;
2656 
2657         if (uiop->uio_iovcnt > IOV_MAX_STACK) {
2658                 iovlen = uiop->uio_iovcnt * sizeof (iovec_t);
2659                 uiod.d_iov = (struct iovec *)kmem_alloc(iovlen, KM_SLEEP);
2660         } else {
2661                 uiod.d_iov = buf;
2662         }
2663 
2664         (void) uiodup(uiop, &uiod.d_uio, uiod.d_iov, uiop->uio_iovcnt);
2665         uiod.d_uio.uio_offset = 0;
2666         uiod.d_mp = mp;
2667         error = rwnext(wqp, &uiod);
2668         if (! uiod.d_mp) {
2669                 uioskip(uiop, *iosize);
2670                 if (iovlen != 0)
2671                         kmem_free(uiod.d_iov, iovlen);
2672                 return (error);
2673         }
2674         ASSERT(mp == uiod.d_mp);
2675         if (error == EINVAL) {
2676                 /*
2677                  * The stream plumbing must have changed while
2678                  * we were away, so just turn off rwnext()s.
2679                  */
2680                 error = 0;
2681         } else if (error == EBUSY || error == EWOULDBLOCK) {
2682                 /*
2683                  * Couldn't enter a perimeter or took a page fault,
2684                  * so fall-back to putnext().
2685                  */
2686                 error = 0;
2687         } else {
2688                 freemsg(mp);
2689                 if (iovlen != 0)
2690                         kmem_free(uiod.d_iov, iovlen);
2691                 return (error);
2692         }
2693         /* Have to check canput before consuming data from the uio */
2694         if (pri == 0) {
2695                 if (!canputnext(wqp) && !(flags & MSG_IGNFLOW)) {
2696                         freemsg(mp);
2697                         if (iovlen != 0)
2698                                 kmem_free(uiod.d_iov, iovlen);
2699                         return (EWOULDBLOCK);
2700                 }
2701         } else {
2702                 if (!bcanputnext(wqp, pri) && !(flags & MSG_IGNFLOW)) {
2703                         freemsg(mp);
2704                         if (iovlen != 0)
2705                                 kmem_free(uiod.d_iov, iovlen);
2706                         return (EWOULDBLOCK);
2707                 }
2708         }
2709         ASSERT(mp == uiod.d_mp);
2710         /* Copyin data from the uio */
2711         if ((error = struioget(wqp, mp, &uiod, 0)) != 0) {
2712                 freemsg(mp);
2713                 if (iovlen != 0)
2714                         kmem_free(uiod.d_iov, iovlen);
2715                 return (error);
2716         }
2717         uioskip(uiop, *iosize);
2718         if (flags & MSG_IGNFLOW) {
2719                 /*
2720                  * XXX Hack: Don't get stuck running service procedures.
2721                  * This is needed for sockfs when sending the unbind message
2722                  * out of the rput procedure - we don't want a put procedure
2723                  * to run service procedures.
2724                  */
2725                 putnext(wqp, mp);
2726         } else {
2727                 stream_willservice(stp);
2728                 putnext(wqp, mp);
2729                 stream_runservice(stp);
2730         }
2731         if (iovlen != 0)
2732                 kmem_free(uiod.d_iov, iovlen);
2733         return (0);
2734 }
2735 
2736 /*
2737  * Write attempts to break the write request into messages conforming
2738  * with the minimum and maximum packet sizes set downstream.
2739  *
2740  * Write will not block if downstream queue is full and
2741  * O_NDELAY is set, otherwise it will block waiting for the queue to get room.
2742  *
2743  * A write of zero bytes gets packaged into a zero length message and sent
2744  * downstream like any other message.
2745  *
2746  * If buffers of the requested sizes are not available, the write will
2747  * sleep until the buffers become available.
2748  *
2749  * Write (if specified) will supply a write offset in a message if it
2750  * makes sense. This can be specified by downstream modules as part of
2751  * a M_SETOPTS message.  Write will not supply the write offset if it
2752  * cannot supply any data in a buffer.  In other words, write will never
2753  * send down an empty packet due to a write offset.
2754  */
2755 /* ARGSUSED2 */
2756 int
2757 strwrite(struct vnode *vp, struct uio *uiop, cred_t *crp)
2758 {
2759         return (strwrite_common(vp, uiop, crp, 0));
2760 }
2761 
2762 /* ARGSUSED2 */
2763 int
2764 strwrite_common(struct vnode *vp, struct uio *uiop, cred_t *crp, int wflag)
2765 {
2766         struct stdata *stp;
2767         struct queue *wqp;
2768         ssize_t rmin, rmax;
2769         ssize_t iosize;
2770         int waitflag;
2771         int tempmode;
2772         int error = 0;
2773         int b_flag;
2774 
2775         ASSERT(vp->v_stream);
2776         stp = vp->v_stream;
2777 
2778         mutex_enter(&stp->sd_lock);
2779 
2780         if ((error = i_straccess(stp, JCWRITE)) != 0) {
2781                 mutex_exit(&stp->sd_lock);
2782                 return (error);
2783         }
2784 
2785         if (stp->sd_flag & (STWRERR|STRHUP|STPLEX)) {
2786                 error = strwriteable(stp, B_TRUE, B_TRUE);
2787                 if (error != 0) {
2788                         mutex_exit(&stp->sd_lock);
2789                         return (error);
2790                 }
2791         }
2792 
2793         mutex_exit(&stp->sd_lock);
2794 
2795         wqp = stp->sd_wrq;
2796 
2797         /* get these values from them cached in the stream head */
2798         rmin = stp->sd_qn_minpsz;
2799         rmax = stp->sd_qn_maxpsz;
2800 
2801         /*
2802          * Check the min/max packet size constraints.  If min packet size
2803          * is non-zero, the write cannot be split into multiple messages
2804          * and still guarantee the size constraints.
2805          */
2806         TRACE_1(TR_FAC_STREAMS_FR, TR_STRWRITE_IN, "strwrite in:q %p", wqp);
2807 
2808         ASSERT((rmax >= 0) || (rmax == INFPSZ));
2809         if (rmax == 0) {
2810                 return (0);
2811         }
2812         if (rmin > 0) {
2813                 if (uiop->uio_resid < rmin) {
2814                         TRACE_3(TR_FAC_STREAMS_FR, TR_STRWRITE_OUT,
2815                             "strwrite out:q %p out %d error %d",
2816                             wqp, 0, ERANGE);
2817                         return (ERANGE);
2818                 }
2819                 if ((rmax != INFPSZ) && (uiop->uio_resid > rmax)) {
2820                         TRACE_3(TR_FAC_STREAMS_FR, TR_STRWRITE_OUT,
2821                             "strwrite out:q %p out %d error %d",
2822                             wqp, 1, ERANGE);
2823                         return (ERANGE);
2824                 }
2825         }
2826 
2827         /*
2828          * Do until count satisfied or error.
2829          */
2830         waitflag = WRITEWAIT | wflag;
2831         if (stp->sd_flag & OLDNDELAY)
2832                 tempmode = uiop->uio_fmode & ~FNDELAY;
2833         else
2834                 tempmode = uiop->uio_fmode;
2835 
2836         if (rmax == INFPSZ)
2837                 rmax = uiop->uio_resid;
2838 
2839         /*
2840          * Note that tempmode does not get used in strput/strmakedata
2841          * but only in strwaitq. The other routines use uio_fmode
2842          * unmodified.
2843          */
2844 
2845         /* LINTED: constant in conditional context */
2846         while (1) {     /* breaks when uio_resid reaches zero */
2847                 /*
2848                  * Determine the size of the next message to be
2849                  * packaged.  May have to break write into several
2850                  * messages based on max packet size.
2851                  */
2852                 iosize = MIN(uiop->uio_resid, rmax);
2853 
2854                 /*
2855                  * Put block downstream when flow control allows it.
2856                  */
2857                 if ((stp->sd_flag & STRDELIM) && (uiop->uio_resid == iosize))
2858                         b_flag = MSGDELIM;
2859                 else
2860                         b_flag = 0;
2861 
2862                 for (;;) {
2863                         int done = 0;
2864 
2865                         error = strput(stp, NULL, uiop, &iosize, b_flag, 0, 0);
2866                         if (error == 0)
2867                                 break;
2868                         if (error != EWOULDBLOCK)
2869                                 goto out;
2870 
2871                         mutex_enter(&stp->sd_lock);
2872                         /*
2873                          * Check for a missed wakeup.
2874                          * Needed since strput did not hold sd_lock across
2875                          * the canputnext.
2876                          */
2877                         if (canputnext(wqp)) {
2878                                 /* Try again */
2879                                 mutex_exit(&stp->sd_lock);
2880                                 continue;
2881                         }
2882                         TRACE_1(TR_FAC_STREAMS_FR, TR_STRWRITE_WAIT,
2883                             "strwrite wait:q %p wait", wqp);
2884                         if ((error = strwaitq(stp, waitflag, (ssize_t)0,
2885                             tempmode, -1, &done)) != 0 || done) {
2886                                 mutex_exit(&stp->sd_lock);
2887                                 if ((vp->v_type == VFIFO) &&
2888                                     (uiop->uio_fmode & FNDELAY) &&
2889                                     (error == EAGAIN))
2890                                         error = 0;
2891                                 goto out;
2892                         }
2893                         TRACE_1(TR_FAC_STREAMS_FR, TR_STRWRITE_WAKE,
2894                             "strwrite wake:q %p awakes", wqp);
2895                         if ((error = i_straccess(stp, JCWRITE)) != 0) {
2896                                 mutex_exit(&stp->sd_lock);
2897                                 goto out;
2898                         }
2899                         mutex_exit(&stp->sd_lock);
2900                 }
2901                 waitflag |= NOINTR;
2902                 TRACE_2(TR_FAC_STREAMS_FR, TR_STRWRITE_RESID,
2903                     "strwrite resid:q %p uiop %p", wqp, uiop);
2904                 if (uiop->uio_resid) {
2905                         /* Recheck for errors - needed for sockets */
2906                         if ((stp->sd_wput_opt & SW_RECHECK_ERR) &&
2907                             (stp->sd_flag & (STWRERR|STRHUP|STPLEX))) {
2908                                 mutex_enter(&stp->sd_lock);
2909                                 error = strwriteable(stp, B_FALSE, B_TRUE);
2910                                 mutex_exit(&stp->sd_lock);
2911                                 if (error != 0)
2912                                         return (error);
2913                         }
2914                         continue;
2915                 }
2916                 break;
2917         }
2918 out:
2919         /*
2920          * For historical reasons, applications expect EAGAIN when a data
2921          * mblk_t cannot be allocated, so change ENOMEM back to EAGAIN.
2922          */
2923         if (error == ENOMEM)
2924                 error = EAGAIN;
2925         TRACE_3(TR_FAC_STREAMS_FR, TR_STRWRITE_OUT,
2926             "strwrite out:q %p out %d error %d", wqp, 2, error);
2927         return (error);
2928 }
2929 
2930 /*
2931  * Stream head write service routine.
2932  * Its job is to wake up any sleeping writers when a queue
2933  * downstream needs data (part of the flow control in putq and getq).
2934  * It also must wake anyone sleeping on a poll().
2935  * For stream head right below mux module, it must also invoke put procedure
2936  * of next downstream module.
2937  */
2938 int
2939 strwsrv(queue_t *q)
2940 {
2941         struct stdata *stp;
2942         queue_t *tq;
2943         qband_t *qbp;
2944         int i;
2945         qband_t *myqbp;
2946         int isevent;
2947         unsigned char   qbf[NBAND];     /* band flushing backenable flags */
2948 
2949         TRACE_1(TR_FAC_STREAMS_FR,
2950             TR_STRWSRV, "strwsrv:q %p", q);
2951         stp = (struct stdata *)q->q_ptr;
2952         ASSERT(qclaimed(q));
2953         mutex_enter(&stp->sd_lock);
2954         ASSERT(!(stp->sd_flag & STPLEX));
2955 
2956         if (stp->sd_flag & WSLEEP) {
2957                 stp->sd_flag &= ~WSLEEP;
2958                 cv_broadcast(&q->q_wait);
2959         }
2960         mutex_exit(&stp->sd_lock);
2961 
2962         /* The other end of a stream pipe went away. */
2963         if ((tq = q->q_next) == NULL) {
2964                 return (0);
2965         }
2966 
2967         /* Find the next module forward that has a service procedure */
2968         claimstr(q);
2969         tq = q->q_nfsrv;
2970         ASSERT(tq != NULL);
2971 
2972         if ((q->q_flag & QBACK)) {
2973                 if ((tq->q_flag & QFULL)) {
2974                         mutex_enter(QLOCK(tq));
2975                         if (!(tq->q_flag & QFULL)) {
2976                                 mutex_exit(QLOCK(tq));
2977                                 goto wakeup;
2978                         }
2979                         /*
2980                          * The queue must have become full again. Set QWANTW
2981                          * again so strwsrv will be back enabled when
2982                          * the queue becomes non-full next time.
2983                          */
2984                         tq->q_flag |= QWANTW;
2985                         mutex_exit(QLOCK(tq));
2986                 } else {
2987                 wakeup:
2988                         pollwakeup(&stp->sd_pollist, POLLWRNORM);
2989                         mutex_enter(&stp->sd_lock);
2990                         if (stp->sd_sigflags & S_WRNORM)
2991                                 strsendsig(stp->sd_siglist, S_WRNORM, 0, 0);
2992                         mutex_exit(&stp->sd_lock);
2993                 }
2994         }
2995 
2996         isevent = 0;
2997         i = 1;
2998         bzero((caddr_t)qbf, NBAND);
2999         mutex_enter(QLOCK(tq));
3000         if ((myqbp = q->q_bandp) != NULL)
3001                 for (qbp = tq->q_bandp; qbp && myqbp; qbp = qbp->qb_next) {
3002                         ASSERT(myqbp);
3003                         if ((myqbp->qb_flag & QB_BACK)) {
3004                                 if (qbp->qb_flag & QB_FULL) {
3005                                         /*
3006                                          * The band must have become full again.
3007                                          * Set QB_WANTW again so strwsrv will
3008                                          * be back enabled when the band becomes
3009                                          * non-full next time.
3010                                          */
3011                                         qbp->qb_flag |= QB_WANTW;
3012                                 } else {
3013                                         isevent = 1;
3014                                         qbf[i] = 1;
3015                                 }
3016                         }
3017                         myqbp = myqbp->qb_next;
3018                         i++;
3019                 }
3020         mutex_exit(QLOCK(tq));
3021 
3022         if (isevent) {
3023                 for (i = tq->q_nband; i; i--) {
3024                         if (qbf[i]) {
3025                                 pollwakeup(&stp->sd_pollist, POLLWRBAND);
3026                                 mutex_enter(&stp->sd_lock);
3027                                 if (stp->sd_sigflags & S_WRBAND)
3028                                         strsendsig(stp->sd_siglist, S_WRBAND,
3029                                             (uchar_t)i, 0);
3030                                 mutex_exit(&stp->sd_lock);
3031                         }
3032                 }
3033         }
3034 
3035         releasestr(q);
3036         return (0);
3037 }
3038 
3039 /*
3040  * Special case of strcopyin/strcopyout for copying
3041  * struct strioctl that can deal with both data
3042  * models.
3043  */
3044 
3045 #ifdef  _LP64
3046 
3047 static int
3048 strcopyin_strioctl(void *from, void *to, int flag, int copyflag)
3049 {
3050         struct  strioctl32 strioc32;
3051         struct  strioctl *striocp;
3052 
3053         if (copyflag & U_TO_K) {
3054                 ASSERT((copyflag & K_TO_K) == 0);
3055 
3056                 if ((flag & FMODELS) == DATAMODEL_ILP32) {
3057                         if (copyin(from, &strioc32, sizeof (strioc32)))
3058                                 return (EFAULT);
3059 
3060                         striocp = (struct strioctl *)to;
3061                         striocp->ic_cmd      = strioc32.ic_cmd;
3062                         striocp->ic_timout = strioc32.ic_timout;
3063                         striocp->ic_len      = strioc32.ic_len;
3064                         striocp->ic_dp       = (char *)(uintptr_t)strioc32.ic_dp;
3065 
3066                 } else { /* NATIVE data model */
3067                         if (copyin(from, to, sizeof (struct strioctl))) {
3068                                 return (EFAULT);
3069                         } else {
3070                                 return (0);
3071                         }
3072                 }
3073         } else {
3074                 ASSERT(copyflag & K_TO_K);
3075                 bcopy(from, to, sizeof (struct strioctl));
3076         }
3077         return (0);
3078 }
3079 
3080 static int
3081 strcopyout_strioctl(void *from, void *to, int flag, int copyflag)
3082 {
3083         struct  strioctl32 strioc32;
3084         struct  strioctl *striocp;
3085 
3086         if (copyflag & U_TO_K) {
3087                 ASSERT((copyflag & K_TO_K) == 0);
3088 
3089                 if ((flag & FMODELS) == DATAMODEL_ILP32) {
3090                         striocp = (struct strioctl *)from;
3091                         strioc32.ic_cmd = striocp->ic_cmd;
3092                         strioc32.ic_timout = striocp->ic_timout;
3093                         strioc32.ic_len = striocp->ic_len;
3094                         strioc32.ic_dp  = (caddr32_t)(uintptr_t)striocp->ic_dp;
3095                         ASSERT((char *)(uintptr_t)strioc32.ic_dp ==
3096                             striocp->ic_dp);
3097 
3098                         if (copyout(&strioc32, to, sizeof (strioc32)))
3099                                 return (EFAULT);
3100 
3101                 } else { /* NATIVE data model */
3102                         if (copyout(from, to, sizeof (struct strioctl))) {
3103                                 return (EFAULT);
3104                         } else {
3105                                 return (0);
3106                         }
3107                 }
3108         } else {
3109                 ASSERT(copyflag & K_TO_K);
3110                 bcopy(from, to, sizeof (struct strioctl));
3111         }
3112         return (0);
3113 }
3114 
3115 #else   /* ! _LP64 */
3116 
3117 /* ARGSUSED2 */
3118 static int
3119 strcopyin_strioctl(void *from, void *to, int flag, int copyflag)
3120 {
3121         return (strcopyin(from, to, sizeof (struct strioctl), copyflag));
3122 }
3123 
3124 /* ARGSUSED2 */
3125 static int
3126 strcopyout_strioctl(void *from, void *to, int flag, int copyflag)
3127 {
3128         return (strcopyout(from, to, sizeof (struct strioctl), copyflag));
3129 }
3130 
3131 #endif  /* _LP64 */
3132 
3133 /*
3134  * Determine type of job control semantics expected by user.  The
3135  * possibilities are:
3136  *      JCREAD  - Behaves like read() on fd; send SIGTTIN
3137  *      JCWRITE - Behaves like write() on fd; send SIGTTOU if TOSTOP set
3138  *      JCSETP  - Sets a value in the stream; send SIGTTOU, ignore TOSTOP
3139  *      JCGETP  - Gets a value in the stream; no signals.
3140  * See straccess in strsubr.c for usage of these values.
3141  *
3142  * This routine also returns -1 for I_STR as a special case; the
3143  * caller must call again with the real ioctl number for
3144  * classification.
3145  */
3146 static int
3147 job_control_type(int cmd)
3148 {
3149         switch (cmd) {
3150         case I_STR:
3151                 return (-1);
3152 
3153         case I_RECVFD:
3154         case I_E_RECVFD:
3155                 return (JCREAD);
3156 
3157         case I_FDINSERT:
3158         case I_SENDFD:
3159                 return (JCWRITE);
3160 
3161         case TCSETA:
3162         case TCSETAW:
3163         case TCSETAF:
3164         case TCSBRK:
3165         case TCXONC:
3166         case TCFLSH:
3167         case TCDSET:    /* Obsolete */
3168         case TIOCSWINSZ:
3169         case TCSETS:
3170         case TCSETSW:
3171         case TCSETSF:
3172         case TIOCSETD:
3173         case TIOCHPCL:
3174         case TIOCSETP:
3175         case TIOCSETN:
3176         case TIOCEXCL:
3177         case TIOCNXCL:
3178         case TIOCFLUSH:
3179         case TIOCSETC:
3180         case TIOCLBIS:
3181         case TIOCLBIC:
3182         case TIOCLSET:
3183         case TIOCSBRK:
3184         case TIOCCBRK:
3185         case TIOCSDTR:
3186         case TIOCCDTR:
3187         case TIOCSLTC:
3188         case TIOCSTOP:
3189         case TIOCSTART:
3190         case TIOCSTI:
3191         case TIOCSPGRP:
3192         case TIOCMSET:
3193         case TIOCMBIS:
3194         case TIOCMBIC:
3195         case TIOCREMOTE:
3196         case TIOCSIGNAL:
3197         case LDSETT:
3198         case LDSMAP:    /* Obsolete */
3199         case DIOCSETP:
3200         case I_FLUSH:
3201         case I_SRDOPT:
3202         case I_SETSIG:
3203         case I_SWROPT:
3204         case I_FLUSHBAND:
3205         case I_SETCLTIME:
3206         case I_SERROPT:
3207         case I_ESETSIG:
3208         case FIONBIO:
3209         case FIOASYNC:
3210         case FIOSETOWN:
3211         case JBOOT:     /* Obsolete */
3212         case JTERM:     /* Obsolete */
3213         case JTIMOM:    /* Obsolete */
3214         case JZOMBOOT:  /* Obsolete */
3215         case JAGENT:    /* Obsolete */
3216         case JTRUN:     /* Obsolete */
3217         case JXTPROTO:  /* Obsolete */
3218         case TIOCSETLD:
3219                 return (JCSETP);
3220         }
3221 
3222         return (JCGETP);
3223 }
3224 
3225 /*
3226  * ioctl for streams
3227  */
3228 int
3229 strioctl(struct vnode *vp, int cmd, intptr_t arg, int flag, int copyflag,
3230     cred_t *crp, int *rvalp)
3231 {
3232         struct stdata *stp;
3233         struct strcmd *scp;
3234         struct strioctl strioc;
3235         struct uio uio;
3236         struct iovec iov;
3237         int access;
3238         mblk_t *mp;
3239         int error = 0;
3240         int done = 0;
3241         ssize_t rmin, rmax;
3242         queue_t *wrq;
3243         queue_t *rdq;
3244         boolean_t kioctl = B_FALSE;
3245         uint32_t auditing = AU_AUDITING();
3246 
3247         if (flag & FKIOCTL) {
3248                 copyflag = K_TO_K;
3249                 kioctl = B_TRUE;
3250         }
3251         ASSERT(vp->v_stream);
3252         ASSERT(copyflag == U_TO_K || copyflag == K_TO_K);
3253         stp = vp->v_stream;
3254 
3255         TRACE_3(TR_FAC_STREAMS_FR, TR_IOCTL_ENTER,
3256             "strioctl:stp %p cmd %X arg %lX", stp, cmd, arg);
3257 
3258         /*
3259          * If the copy is kernel to kernel, make sure that the FNATIVE
3260          * flag is set.  After this it would be a serious error to have
3261          * no model flag.
3262          */
3263         if (copyflag == K_TO_K)
3264                 flag = (flag & ~FMODELS) | FNATIVE;
3265 
3266         ASSERT((flag & FMODELS) != 0);
3267 
3268         wrq = stp->sd_wrq;
3269         rdq = _RD(wrq);
3270 
3271         access = job_control_type(cmd);
3272 
3273         /* We should never see these here, should be handled by iwscn */
3274         if (cmd == SRIOCSREDIR || cmd == SRIOCISREDIR)
3275                 return (EINVAL);
3276 
3277         mutex_enter(&stp->sd_lock);
3278         if ((access != -1) && ((error = i_straccess(stp, access)) != 0)) {
3279                 mutex_exit(&stp->sd_lock);
3280                 return (error);
3281         }
3282         mutex_exit(&stp->sd_lock);
3283 
3284         /*
3285          * Check for sgttyb-related ioctls first, and complain as
3286          * necessary.
3287          */
3288         switch (cmd) {
3289         case TIOCGETP:
3290         case TIOCSETP:
3291         case TIOCSETN:
3292                 if (sgttyb_handling >= 2 && !sgttyb_complaint) {
3293                         sgttyb_complaint = B_TRUE;
3294                         cmn_err(CE_NOTE,
3295                             "application used obsolete TIOC[GS]ET");
3296                 }
3297                 if (sgttyb_handling >= 3) {
3298                         tsignal(curthread, SIGSYS);
3299                         return (EIO);
3300                 }
3301                 break;
3302         }
3303 
3304         mutex_enter(&stp->sd_lock);
3305 
3306         switch (cmd) {
3307         case I_RECVFD:
3308         case I_E_RECVFD:
3309         case I_PEEK:
3310         case I_NREAD:
3311         case FIONREAD:
3312         case FIORDCHK:
3313         case I_ATMARK:
3314         case FIONBIO:
3315         case FIOASYNC:
3316                 if (stp->sd_flag & (STRDERR|STPLEX)) {
3317                         error = strgeterr(stp, STRDERR|STPLEX, 0);
3318                         if (error != 0) {
3319                                 mutex_exit(&stp->sd_lock);
3320                                 return (error);
3321                         }
3322                 }
3323                 break;
3324 
3325         default:
3326                 if (stp->sd_flag & (STRDERR|STWRERR|STPLEX)) {
3327                         error = strgeterr(stp, STRDERR|STWRERR|STPLEX, 0);
3328                         if (error != 0) {
3329                                 mutex_exit(&stp->sd_lock);
3330                                 return (error);
3331                         }
3332                 }
3333         }
3334 
3335         mutex_exit(&stp->sd_lock);
3336 
3337         switch (cmd) {
3338         default:
3339                 /*
3340                  * The stream head has hardcoded knowledge of a
3341                  * miscellaneous collection of terminal-, keyboard- and
3342                  * mouse-related ioctls, enumerated below.  This hardcoded
3343                  * knowledge allows the stream head to automatically
3344                  * convert transparent ioctl requests made by userland
3345                  * programs into I_STR ioctls which many old STREAMS
3346                  * modules and drivers require.
3347                  *
3348                  * No new ioctls should ever be added to this list.
3349                  * Instead, the STREAMS module or driver should be written
3350                  * to either handle transparent ioctls or require any
3351                  * userland programs to use I_STR ioctls (by returning
3352                  * EINVAL to any transparent ioctl requests).
3353                  *
3354                  * More importantly, removing ioctls from this list should
3355                  * be done with the utmost care, since our STREAMS modules
3356                  * and drivers *count* on the stream head performing this
3357                  * conversion, and thus may panic while processing
3358                  * transparent ioctl request for one of these ioctls (keep
3359                  * in mind that third party modules and drivers may have
3360                  * similar problems).
3361                  */
3362                 if (((cmd & IOCTYPE) == LDIOC) ||
3363                     ((cmd & IOCTYPE) == tIOC) ||
3364                     ((cmd & IOCTYPE) == TIOC) ||
3365                     ((cmd & IOCTYPE) == KIOC) ||
3366                     ((cmd & IOCTYPE) == MSIOC) ||
3367                     ((cmd & IOCTYPE) == VUIOC)) {
3368                         /*
3369                          * The ioctl is a tty ioctl - set up strioc buffer
3370                          * and call strdoioctl() to do the work.
3371                          */
3372                         if (stp->sd_flag & STRHUP)
3373                                 return (ENXIO);
3374                         strioc.ic_cmd = cmd;
3375                         strioc.ic_timout = INFTIM;
3376 
3377                         switch (cmd) {
3378 
3379                         case TCXONC:
3380                         case TCSBRK:
3381                         case TCFLSH:
3382                         case TCDSET:
3383                                 {
3384                                 int native_arg = (int)arg;
3385                                 strioc.ic_len = sizeof (int);
3386                                 strioc.ic_dp = (char *)&native_arg;
3387                                 return (strdoioctl(stp, &strioc, flag,
3388                                     K_TO_K, crp, rvalp));
3389                                 }
3390 
3391                         case TCSETA:
3392                         case TCSETAW:
3393                         case TCSETAF:
3394                                 strioc.ic_len = sizeof (struct termio);
3395                                 strioc.ic_dp = (char *)arg;
3396                                 return (strdoioctl(stp, &strioc, flag,
3397                                     copyflag, crp, rvalp));
3398 
3399                         case TCSETS:
3400                         case TCSETSW:
3401                         case TCSETSF:
3402                                 strioc.ic_len = sizeof (struct termios);
3403                                 strioc.ic_dp = (char *)arg;
3404                                 return (strdoioctl(stp, &strioc, flag,
3405                                     copyflag, crp, rvalp));
3406 
3407                         case LDSETT:
3408                                 strioc.ic_len = sizeof (struct termcb);
3409                                 strioc.ic_dp = (char *)arg;
3410                                 return (strdoioctl(stp, &strioc, flag,
3411                                     copyflag, crp, rvalp));
3412 
3413                         case TIOCSETP:
3414                                 strioc.ic_len = sizeof (struct sgttyb);
3415                                 strioc.ic_dp = (char *)arg;
3416                                 return (strdoioctl(stp, &strioc, flag,
3417                                     copyflag, crp, rvalp));
3418 
3419                         case TIOCSTI:
3420                                 if ((flag & FREAD) == 0 &&
3421                                     secpolicy_sti(crp) != 0) {
3422                                         return (EPERM);
3423                                 }
3424                                 mutex_enter(&stp->sd_lock);
3425                                 mutex_enter(&curproc->p_splock);
3426                                 if (stp->sd_sidp != curproc->p_sessp->s_sidp &&
3427                                     secpolicy_sti(crp) != 0) {
3428                                         mutex_exit(&curproc->p_splock);
3429                                         mutex_exit(&stp->sd_lock);
3430                                         return (EACCES);
3431                                 }
3432                                 mutex_exit(&curproc->p_splock);
3433                                 mutex_exit(&stp->sd_lock);
3434 
3435                                 strioc.ic_len = sizeof (char);
3436                                 strioc.ic_dp = (char *)arg;
3437                                 return (strdoioctl(stp, &strioc, flag,
3438                                     copyflag, crp, rvalp));
3439 
3440                         case TIOCSWINSZ:
3441                                 strioc.ic_len = sizeof (struct winsize);
3442                                 strioc.ic_dp = (char *)arg;
3443                                 return (strdoioctl(stp, &strioc, flag,
3444                                     copyflag, crp, rvalp));
3445 
3446                         case TIOCSSIZE:
3447                                 strioc.ic_len = sizeof (struct ttysize);
3448                                 strioc.ic_dp = (char *)arg;
3449                                 return (strdoioctl(stp, &strioc, flag,
3450                                     copyflag, crp, rvalp));
3451 
3452                         case TIOCSSOFTCAR:
3453                         case KIOCTRANS:
3454                         case KIOCTRANSABLE:
3455                         case KIOCCMD:
3456                         case KIOCSDIRECT:
3457                         case KIOCSCOMPAT:
3458                         case KIOCSKABORTEN:
3459                         case KIOCSRPTDELAY:
3460                         case KIOCSRPTRATE:
3461                         case VUIDSFORMAT:
3462                         case TIOCSPPS:
3463                                 strioc.ic_len = sizeof (int);
3464                                 strioc.ic_dp = (char *)arg;
3465                                 return (strdoioctl(stp, &strioc, flag,
3466                                     copyflag, crp, rvalp));
3467 
3468                         case KIOCSETKEY:
3469                         case KIOCGETKEY:
3470                                 strioc.ic_len = sizeof (struct kiockey);
3471                                 strioc.ic_dp = (char *)arg;
3472                                 return (strdoioctl(stp, &strioc, flag,
3473                                     copyflag, crp, rvalp));
3474 
3475                         case KIOCSKEY:
3476                         case KIOCGKEY:
3477                                 strioc.ic_len = sizeof (struct kiockeymap);
3478                                 strioc.ic_dp = (char *)arg;
3479                                 return (strdoioctl(stp, &strioc, flag,
3480                                     copyflag, crp, rvalp));
3481 
3482                         case KIOCSLED:
3483                                 /* arg is a pointer to char */
3484                                 strioc.ic_len = sizeof (char);
3485                                 strioc.ic_dp = (char *)arg;
3486                                 return (strdoioctl(stp, &strioc, flag,
3487                                     copyflag, crp, rvalp));
3488 
3489                         case MSIOSETPARMS:
3490                                 strioc.ic_len = sizeof (Ms_parms);
3491                                 strioc.ic_dp = (char *)arg;
3492                                 return (strdoioctl(stp, &strioc, flag,
3493                                     copyflag, crp, rvalp));
3494 
3495                         case VUIDSADDR:
3496                         case VUIDGADDR:
3497                                 strioc.ic_len = sizeof (struct vuid_addr_probe);
3498                                 strioc.ic_dp = (char *)arg;
3499                                 return (strdoioctl(stp, &strioc, flag,
3500                                     copyflag, crp, rvalp));
3501 
3502                         /*
3503                          * These M_IOCTL's don't require any data to be sent
3504                          * downstream, and the driver will allocate and link
3505                          * on its own mblk_t upon M_IOCACK -- thus we set
3506                          * ic_len to zero and set ic_dp to arg so we know
3507                          * where to copyout to later.
3508                          */
3509                         case TIOCGSOFTCAR:
3510                         case TIOCGWINSZ:
3511                         case TIOCGSIZE:
3512                         case KIOCGTRANS:
3513                         case KIOCGTRANSABLE:
3514                         case KIOCTYPE:
3515                         case KIOCGDIRECT:
3516                         case KIOCGCOMPAT:
3517                         case KIOCLAYOUT:
3518                         case KIOCGLED:
3519                         case MSIOGETPARMS:
3520                         case MSIOBUTTONS:
3521                         case VUIDGFORMAT:
3522                         case TIOCGPPS:
3523                         case TIOCGPPSEV:
3524                         case TCGETA:
3525                         case TCGETS:
3526                         case LDGETT:
3527                         case TIOCGETP:
3528                         case KIOCGRPTDELAY:
3529                         case KIOCGRPTRATE:
3530                                 strioc.ic_len = 0;
3531                                 strioc.ic_dp = (char *)arg;
3532                                 return (strdoioctl(stp, &strioc, flag,
3533                                     copyflag, crp, rvalp));
3534                         }
3535                 }
3536 
3537                 /*
3538                  * Unknown cmd - send it down as a transparent ioctl.
3539                  */
3540                 strioc.ic_cmd = cmd;
3541                 strioc.ic_timout = INFTIM;
3542                 strioc.ic_len = TRANSPARENT;
3543                 strioc.ic_dp = (char *)&arg;
3544 
3545                 return (strdoioctl(stp, &strioc, flag, copyflag, crp, rvalp));
3546 
3547         case I_STR:
3548                 /*
3549                  * Stream ioctl.  Read in an strioctl buffer from the user
3550                  * along with any data specified and send it downstream.
3551                  * Strdoioctl will wait allow only one ioctl message at
3552                  * a time, and waits for the acknowledgement.
3553                  */
3554 
3555                 if (stp->sd_flag & STRHUP)
3556                         return (ENXIO);
3557 
3558                 error = strcopyin_strioctl((void *)arg, &strioc, flag,
3559                     copyflag);
3560                 if (error != 0)
3561                         return (error);
3562 
3563                 if ((strioc.ic_len < 0) || (strioc.ic_timout < -1))
3564                         return (EINVAL);
3565 
3566                 access = job_control_type(strioc.ic_cmd);
3567                 mutex_enter(&stp->sd_lock);
3568                 if ((access != -1) &&
3569                     ((error = i_straccess(stp, access)) != 0)) {
3570                         mutex_exit(&stp->sd_lock);
3571                         return (error);
3572                 }
3573                 mutex_exit(&stp->sd_lock);
3574 
3575                 /*
3576                  * The I_STR facility provides a trap door for malicious
3577                  * code to send down bogus streamio(7I) ioctl commands to
3578                  * unsuspecting STREAMS modules and drivers which expect to
3579                  * only get these messages from the stream head.
3580                  * Explicitly prohibit any streamio ioctls which can be
3581                  * passed downstream by the stream head.  Note that we do
3582                  * not block all streamio ioctls because the ioctl
3583                  * numberspace is not well managed and thus it's possible
3584                  * that a module or driver's ioctl numbers may accidentally
3585                  * collide with them.
3586                  */
3587                 switch (strioc.ic_cmd) {
3588                 case I_LINK:
3589                 case I_PLINK:
3590                 case I_UNLINK:
3591                 case I_PUNLINK:
3592                 case _I_GETPEERCRED:
3593                 case _I_PLINK_LH:
3594                         return (EINVAL);
3595                 }
3596 
3597                 error = strdoioctl(stp, &strioc, flag, copyflag, crp, rvalp);
3598                 if (error == 0) {
3599                         error = strcopyout_strioctl(&strioc, (void *)arg,
3600                             flag, copyflag);
3601                 }
3602                 return (error);
3603 
3604         case _I_CMD:
3605                 /*
3606                  * Like I_STR, but without using M_IOC* messages and without
3607                  * copyins/copyouts beyond the passed-in argument.
3608                  */
3609                 if (stp->sd_flag & STRHUP)
3610                         return (ENXIO);
3611 
3612                 if ((scp = kmem_alloc(sizeof (strcmd_t), KM_NOSLEEP)) == NULL)
3613                         return (ENOMEM);
3614 
3615                 if (copyin((void *)arg, scp, sizeof (strcmd_t))) {
3616                         kmem_free(scp, sizeof (strcmd_t));
3617                         return (EFAULT);
3618                 }
3619 
3620                 access = job_control_type(scp->sc_cmd);
3621                 mutex_enter(&stp->sd_lock);
3622                 if (access != -1 && (error = i_straccess(stp, access)) != 0) {
3623                         mutex_exit(&stp->sd_lock);
3624                         kmem_free(scp, sizeof (strcmd_t));
3625                         return (error);
3626                 }
3627                 mutex_exit(&stp->sd_lock);
3628 
3629                 *rvalp = 0;
3630                 if ((error = strdocmd(stp, scp, crp)) == 0) {
3631                         if (copyout(scp, (void *)arg, sizeof (strcmd_t)))
3632                                 error = EFAULT;
3633                 }
3634                 kmem_free(scp, sizeof (strcmd_t));
3635                 return (error);
3636 
3637         case I_NREAD:
3638                 /*
3639                  * Return number of bytes of data in first message
3640                  * in queue in "arg" and return the number of messages
3641                  * in queue in return value.
3642                  */
3643         {
3644                 size_t  size;
3645                 int     retval;
3646                 int     count = 0;
3647 
3648                 mutex_enter(QLOCK(rdq));
3649 
3650                 size = msgdsize(rdq->q_first);
3651                 for (mp = rdq->q_first; mp != NULL; mp = mp->b_next)
3652                         count++;
3653 
3654                 mutex_exit(QLOCK(rdq));
3655                 if (stp->sd_struiordq) {
3656                         infod_t infod;
3657 
3658                         infod.d_cmd = INFOD_COUNT;
3659                         infod.d_count = 0;
3660                         if (count == 0) {
3661                                 infod.d_cmd |= INFOD_FIRSTBYTES;
3662                                 infod.d_bytes = 0;
3663                         }
3664                         infod.d_res = 0;
3665                         (void) infonext(rdq, &infod);
3666                         count += infod.d_count;
3667                         if (infod.d_res & INFOD_FIRSTBYTES)
3668                                 size = infod.d_bytes;
3669                 }
3670 
3671                 /*
3672                  * Drop down from size_t to the "int" required by the
3673                  * interface.  Cap at INT_MAX.
3674                  */
3675                 retval = MIN(size, INT_MAX);
3676                 error = strcopyout(&retval, (void *)arg, sizeof (retval),
3677                     copyflag);
3678                 if (!error)
3679                         *rvalp = count;
3680                 return (error);
3681         }
3682 
3683         case FIONREAD:
3684                 /*
3685                  * Return number of bytes of data in all data messages
3686                  * in queue in "arg".
3687                  */
3688         {
3689                 size_t  size = 0;
3690                 int     retval;
3691 
3692                 mutex_enter(QLOCK(rdq));
3693                 for (mp = rdq->q_first; mp != NULL; mp = mp->b_next)
3694                         size += msgdsize(mp);
3695                 mutex_exit(QLOCK(rdq));
3696 
3697                 if (stp->sd_struiordq) {
3698                         infod_t infod;
3699 
3700                         infod.d_cmd = INFOD_BYTES;
3701                         infod.d_res = 0;
3702                         infod.d_bytes = 0;
3703                         (void) infonext(rdq, &infod);
3704                         size += infod.d_bytes;
3705                 }
3706 
3707                 /*
3708                  * Drop down from size_t to the "int" required by the
3709                  * interface.  Cap at INT_MAX.
3710                  */
3711                 retval = MIN(size, INT_MAX);
3712                 error = strcopyout(&retval, (void *)arg, sizeof (retval),
3713                     copyflag);
3714 
3715                 *rvalp = 0;
3716                 return (error);
3717         }
3718         case FIORDCHK:
3719                 /*
3720                  * FIORDCHK does not use arg value (like FIONREAD),
3721                  * instead a count is returned. I_NREAD value may
3722                  * not be accurate but safe. The real thing to do is
3723                  * to add the msgdsizes of all data  messages until
3724                  * a non-data message.
3725                  */
3726         {
3727                 size_t size = 0;
3728 
3729                 mutex_enter(QLOCK(rdq));
3730                 for (mp = rdq->q_first; mp != NULL; mp = mp->b_next)
3731                         size += msgdsize(mp);
3732                 mutex_exit(QLOCK(rdq));
3733 
3734                 if (stp->sd_struiordq) {
3735                         infod_t infod;
3736 
3737                         infod.d_cmd = INFOD_BYTES;
3738                         infod.d_res = 0;
3739                         infod.d_bytes = 0;
3740                         (void) infonext(rdq, &infod);
3741                         size += infod.d_bytes;
3742                 }
3743 
3744                 /*
3745                  * Since ioctl returns an int, and memory sizes under
3746                  * LP64 may not fit, we return INT_MAX if the count was
3747                  * actually greater.
3748                  */
3749                 *rvalp = MIN(size, INT_MAX);
3750                 return (0);
3751         }
3752 
3753         case I_FIND:
3754                 /*
3755                  * Get module name.
3756                  */
3757         {
3758                 char mname[FMNAMESZ + 1];
3759                 queue_t *q;
3760 
3761                 error = (copyflag & U_TO_K ? copyinstr : copystr)((void *)arg,
3762                     mname, FMNAMESZ + 1, NULL);
3763                 if (error)
3764                         return ((error == ENAMETOOLONG) ? EINVAL : EFAULT);
3765 
3766                 /*
3767                  * Return EINVAL if we're handed a bogus module name.
3768                  */
3769                 if (fmodsw_find(mname, FMODSW_LOAD) == NULL) {
3770                         TRACE_0(TR_FAC_STREAMS_FR,
3771                             TR_I_CANT_FIND, "couldn't I_FIND");
3772                         return (EINVAL);
3773                 }
3774 
3775                 *rvalp = 0;
3776 
3777                 /* Look downstream to see if module is there. */
3778                 claimstr(stp->sd_wrq);
3779                 for (q = stp->sd_wrq->q_next; q; q = q->q_next) {
3780                         if (q->q_flag & QREADR) {
3781                                 q = NULL;
3782                                 break;
3783                         }
3784                         if (strcmp(mname, Q2NAME(q)) == 0)
3785                                 break;
3786                 }
3787                 releasestr(stp->sd_wrq);
3788 
3789                 *rvalp = (q ? 1 : 0);
3790                 return (error);
3791         }
3792 
3793         case I_PUSH:
3794         case __I_PUSH_NOCTTY:
3795                 /*
3796                  * Push a module.
3797                  * For the case __I_PUSH_NOCTTY push a module but
3798                  * do not allocate controlling tty. See bugid 4025044
3799                  */
3800 
3801         {
3802                 char mname[FMNAMESZ + 1];
3803                 fmodsw_impl_t *fp;
3804                 dev_t dummydev;
3805 
3806                 if (stp->sd_flag & STRHUP)
3807                         return (ENXIO);
3808 
3809                 /*
3810                  * Get module name and look up in fmodsw.
3811                  */
3812                 error = (copyflag & U_TO_K ? copyinstr : copystr)((void *)arg,
3813                     mname, FMNAMESZ + 1, NULL);
3814                 if (error)
3815                         return ((error == ENAMETOOLONG) ? EINVAL : EFAULT);
3816 
3817                 if ((fp = fmodsw_find(mname, FMODSW_HOLD | FMODSW_LOAD)) ==
3818                     NULL)
3819                         return (EINVAL);
3820 
3821                 TRACE_2(TR_FAC_STREAMS_FR, TR_I_PUSH,
3822                     "I_PUSH:fp %p stp %p", fp, stp);
3823 
3824                 if (error = strstartplumb(stp, flag, cmd)) {
3825                         fmodsw_rele(fp);
3826                         return (error);
3827                 }
3828 
3829                 /*
3830                  * See if any more modules can be pushed on this stream.
3831                  * Note that this check must be done after strstartplumb()
3832                  * since otherwise multiple threads issuing I_PUSHes on
3833                  * the same stream will be able to exceed nstrpush.
3834                  */
3835                 mutex_enter(&stp->sd_lock);
3836                 if (stp->sd_pushcnt >= nstrpush) {
3837                         fmodsw_rele(fp);
3838                         strendplumb(stp);
3839                         mutex_exit(&stp->sd_lock);
3840                         return (EINVAL);
3841                 }
3842                 mutex_exit(&stp->sd_lock);
3843 
3844                 /*
3845                  * Push new module and call its open routine
3846                  * via qattach().  Modules don't change device
3847                  * numbers, so just ignore dummydev here.
3848                  */
3849                 dummydev = vp->v_rdev;
3850                 if ((error = qattach(rdq, &dummydev, 0, crp, fp,
3851                     B_FALSE)) == 0) {
3852                         if (vp->v_type == VCHR && /* sorry, no pipes allowed */
3853                             (cmd == I_PUSH) && (stp->sd_flag & STRISTTY)) {
3854                                 /*
3855                                  * try to allocate it as a controlling terminal
3856                                  */
3857                                 (void) strctty(stp);
3858                         }
3859                 }
3860 
3861                 mutex_enter(&stp->sd_lock);
3862 
3863                 /*
3864                  * As a performance concern we are caching the values of
3865                  * q_minpsz and q_maxpsz of the module below the stream
3866                  * head in the stream head.
3867                  */
3868                 mutex_enter(QLOCK(stp->sd_wrq->q_next));
3869                 rmin = stp->sd_wrq->q_next->q_minpsz;
3870                 rmax = stp->sd_wrq->q_next->q_maxpsz;
3871                 mutex_exit(QLOCK(stp->sd_wrq->q_next));
3872 
3873                 /* Do this processing here as a performance concern */
3874                 if (strmsgsz != 0) {
3875                         if (rmax == INFPSZ)
3876                                 rmax = strmsgsz;
3877                         else  {
3878                                 if (vp->v_type == VFIFO)
3879                                         rmax = MIN(PIPE_BUF, rmax);
3880                                 else    rmax = MIN(strmsgsz, rmax);
3881                         }
3882                 }
3883 
3884                 mutex_enter(QLOCK(wrq));
3885                 stp->sd_qn_minpsz = rmin;
3886                 stp->sd_qn_maxpsz = rmax;
3887                 mutex_exit(QLOCK(wrq));
3888 
3889                 strendplumb(stp);
3890                 mutex_exit(&stp->sd_lock);
3891                 return (error);
3892         }
3893 
3894         case I_POP:
3895         {
3896                 queue_t *q;
3897 
3898                 if (stp->sd_flag & STRHUP)
3899                         return (ENXIO);
3900                 if (!wrq->q_next)    /* for broken pipes */
3901                         return (EINVAL);
3902 
3903                 if (error = strstartplumb(stp, flag, cmd))
3904                         return (error);
3905 
3906                 /*
3907                  * If there is an anchor on this stream and popping
3908                  * the current module would attempt to pop through the
3909                  * anchor, then disallow the pop unless we have sufficient
3910                  * privileges; take the cheapest (non-locking) check
3911                  * first.
3912                  */
3913                 if (secpolicy_ip_config(crp, B_TRUE) != 0 ||
3914                     (stp->sd_anchorzone != crgetzoneid(crp))) {
3915                         mutex_enter(&stp->sd_lock);
3916                         /*
3917                          * Anchors only apply if there's at least one
3918                          * module on the stream (sd_pushcnt > 0).
3919                          */
3920                         if (stp->sd_pushcnt > 0 &&
3921                             stp->sd_pushcnt == stp->sd_anchor &&
3922                             stp->sd_vnode->v_type != VFIFO) {
3923                                 strendplumb(stp);
3924                                 mutex_exit(&stp->sd_lock);
3925                                 if (stp->sd_anchorzone != crgetzoneid(crp))
3926                                         return (EINVAL);
3927                                 /* Audit and report error */
3928                                 return (secpolicy_ip_config(crp, B_FALSE));
3929                         }
3930                         mutex_exit(&stp->sd_lock);
3931                 }
3932 
3933                 q = wrq->q_next;
3934                 TRACE_2(TR_FAC_STREAMS_FR, TR_I_POP,
3935                     "I_POP:%p from %p", q, stp);
3936                 if (q->q_next == NULL || (q->q_flag & (QREADR|QISDRV))) {
3937                         error = EINVAL;
3938                 } else {
3939                         qdetach(_RD(q), 1, flag, crp, B_FALSE);
3940                         error = 0;
3941                 }
3942                 mutex_enter(&stp->sd_lock);
3943 
3944                 /*
3945                  * As a performance concern we are caching the values of
3946                  * q_minpsz and q_maxpsz of the module below the stream
3947                  * head in the stream head.
3948                  */
3949                 mutex_enter(QLOCK(wrq->q_next));
3950                 rmin = wrq->q_next->q_minpsz;
3951                 rmax = wrq->q_next->q_maxpsz;
3952                 mutex_exit(QLOCK(wrq->q_next));
3953 
3954                 /* Do this processing here as a performance concern */
3955                 if (strmsgsz != 0) {
3956                         if (rmax == INFPSZ)
3957                                 rmax = strmsgsz;
3958                         else  {
3959                                 if (vp->v_type == VFIFO)
3960                                         rmax = MIN(PIPE_BUF, rmax);
3961                                 else    rmax = MIN(strmsgsz, rmax);
3962                         }
3963                 }
3964 
3965                 mutex_enter(QLOCK(wrq));
3966                 stp->sd_qn_minpsz = rmin;
3967                 stp->sd_qn_maxpsz = rmax;
3968                 mutex_exit(QLOCK(wrq));
3969 
3970                 /* If we popped through the anchor, then reset the anchor. */
3971                 if (stp->sd_pushcnt < stp->sd_anchor) {
3972                         stp->sd_anchor = 0;
3973                         stp->sd_anchorzone = 0;
3974                 }
3975                 strendplumb(stp);
3976                 mutex_exit(&stp->sd_lock);
3977                 return (error);
3978         }
3979 
3980         case _I_MUXID2FD:
3981         {
3982                 /*
3983                  * Create a fd for a I_PLINK'ed lower stream with a given
3984                  * muxid.  With the fd, application can send down ioctls,
3985                  * like I_LIST, to the previously I_PLINK'ed stream.  Note
3986                  * that after getting the fd, the application has to do an
3987                  * I_PUNLINK on the muxid before it can do any operation
3988                  * on the lower stream.  This is required by spec1170.
3989                  *
3990                  * The fd used to do this ioctl should point to the same
3991                  * controlling device used to do the I_PLINK.  If it uses
3992                  * a different stream or an invalid muxid, I_MUXID2FD will
3993                  * fail.  The error code is set to EINVAL.
3994                  *
3995                  * The intended use of this interface is the following.
3996                  * An application I_PLINK'ed a stream and exits.  The fd
3997                  * to the lower stream is gone.  Another application
3998                  * wants to get a fd to the lower stream, it uses I_MUXID2FD.
3999                  */
4000                 int muxid = (int)arg;
4001                 int fd;
4002                 linkinfo_t *linkp;
4003                 struct file *fp;
4004                 netstack_t *ns;
4005                 str_stack_t *ss;
4006 
4007                 /*
4008                  * Do not allow the wildcard muxid.  This ioctl is not
4009                  * intended to find arbitrary link.
4010                  */
4011                 if (muxid == 0) {
4012                         return (EINVAL);
4013                 }
4014 
4015                 ns = netstack_find_by_cred(crp);
4016                 ASSERT(ns != NULL);
4017                 ss = ns->netstack_str;
4018                 ASSERT(ss != NULL);
4019 
4020                 mutex_enter(&muxifier);
4021                 linkp = findlinks(vp->v_stream, muxid, LINKPERSIST, ss);
4022                 if (linkp == NULL) {
4023                         mutex_exit(&muxifier);
4024                         netstack_rele(ss->ss_netstack);
4025                         return (EINVAL);
4026                 }
4027 
4028                 if ((fd = ufalloc(0)) == -1) {
4029                         mutex_exit(&muxifier);
4030                         netstack_rele(ss->ss_netstack);
4031                         return (EMFILE);
4032                 }
4033                 fp = linkp->li_fpdown;
4034                 mutex_enter(&fp->f_tlock);
4035                 fp->f_count++;
4036                 mutex_exit(&fp->f_tlock);
4037                 mutex_exit(&muxifier);
4038                 setf(fd, fp);
4039                 *rvalp = fd;
4040                 netstack_rele(ss->ss_netstack);
4041                 return (0);
4042         }
4043 
4044         case _I_INSERT:
4045         {
4046                 /*
4047                  * To insert a module to a given position in a stream.
4048                  * In the first release, only allow privileged user
4049                  * to use this ioctl. Furthermore, the insert is only allowed
4050                  * below an anchor if the zoneid is the same as the zoneid
4051                  * which created the anchor.
4052                  *
4053                  * Note that we do not plan to support this ioctl
4054                  * on pipes in the first release.  We want to learn more
4055                  * about the implications of these ioctls before extending
4056                  * their support.  And we do not think these features are
4057                  * valuable for pipes.
4058                  */
4059                 STRUCT_DECL(strmodconf, strmodinsert);
4060                 char mod_name[FMNAMESZ + 1];
4061                 fmodsw_impl_t *fp;
4062                 dev_t dummydev;
4063                 queue_t *tmp_wrq;
4064                 int pos;
4065                 boolean_t is_insert;
4066 
4067                 STRUCT_INIT(strmodinsert, flag);
4068                 if (stp->sd_flag & STRHUP)
4069                         return (ENXIO);
4070                 if (STRMATED(stp))
4071                         return (EINVAL);
4072                 if ((error = secpolicy_net_config(crp, B_FALSE)) != 0)
4073                         return (error);
4074                 if (stp->sd_anchor != 0 &&
4075                     stp->sd_anchorzone != crgetzoneid(crp))
4076                         return (EINVAL);
4077 
4078                 error = strcopyin((void *)arg, STRUCT_BUF(strmodinsert),
4079                     STRUCT_SIZE(strmodinsert), copyflag);
4080                 if (error)
4081                         return (error);
4082 
4083                 /*
4084                  * Get module name and look up in fmodsw.
4085                  */
4086                 error = (copyflag & U_TO_K ? copyinstr :
4087                     copystr)(STRUCT_FGETP(strmodinsert, mod_name),
4088                     mod_name, FMNAMESZ + 1, NULL);
4089                 if (error)
4090                         return ((error == ENAMETOOLONG) ? EINVAL : EFAULT);
4091 
4092                 if ((fp = fmodsw_find(mod_name, FMODSW_HOLD | FMODSW_LOAD)) ==
4093                     NULL)
4094                         return (EINVAL);
4095 
4096                 if (error = strstartplumb(stp, flag, cmd)) {
4097                         fmodsw_rele(fp);
4098                         return (error);
4099                 }
4100 
4101                 /*
4102                  * Is this _I_INSERT just like an I_PUSH?  We need to know
4103                  * this because we do some optimizations if this is a
4104                  * module being pushed.
4105                  */
4106                 pos = STRUCT_FGET(strmodinsert, pos);
4107                 is_insert = (pos != 0);
4108 
4109                 /*
4110                  * Make sure pos is valid.  Even though it is not an I_PUSH,
4111                  * we impose the same limit on the number of modules in a
4112                  * stream.
4113                  */
4114                 mutex_enter(&stp->sd_lock);
4115                 if (stp->sd_pushcnt >= nstrpush || pos < 0 ||
4116                     pos > stp->sd_pushcnt) {
4117                         fmodsw_rele(fp);
4118                         strendplumb(stp);
4119                         mutex_exit(&stp->sd_lock);
4120                         return (EINVAL);
4121                 }
4122                 if (stp->sd_anchor != 0) {
4123                         /*
4124                          * Is this insert below the anchor?
4125                          * Pushcnt hasn't been increased yet hence
4126                          * we test for greater than here, and greater or
4127                          * equal after qattach.
4128                          */
4129                         if (pos > (stp->sd_pushcnt - stp->sd_anchor) &&
4130                             stp->sd_anchorzone != crgetzoneid(crp)) {
4131                                 fmodsw_rele(fp);
4132                                 strendplumb(stp);
4133                                 mutex_exit(&stp->sd_lock);
4134                                 return (EPERM);
4135                         }
4136                 }
4137 
4138                 mutex_exit(&stp->sd_lock);
4139 
4140                 /*
4141                  * First find the correct position this module to
4142                  * be inserted.  We don't need to call claimstr()
4143                  * as the stream should not be changing at this point.
4144                  *
4145                  * Insert new module and call its open routine
4146                  * via qattach().  Modules don't change device
4147                  * numbers, so just ignore dummydev here.
4148                  */
4149                 for (tmp_wrq = stp->sd_wrq; pos > 0;
4150                     tmp_wrq = tmp_wrq->q_next, pos--) {
4151                         ASSERT(SAMESTR(tmp_wrq));
4152                 }
4153                 dummydev = vp->v_rdev;
4154                 if ((error = qattach(_RD(tmp_wrq), &dummydev, 0, crp,
4155                     fp, is_insert)) != 0) {
4156                         mutex_enter(&stp->sd_lock);
4157                         strendplumb(stp);
4158                         mutex_exit(&stp->sd_lock);
4159                         return (error);
4160                 }
4161 
4162                 mutex_enter(&stp->sd_lock);
4163 
4164                 /*
4165                  * As a performance concern we are caching the values of
4166                  * q_minpsz and q_maxpsz of the module below the stream
4167                  * head in the stream head.
4168                  */
4169                 if (!is_insert) {
4170                         mutex_enter(QLOCK(stp->sd_wrq->q_next));
4171                         rmin = stp->sd_wrq->q_next->q_minpsz;
4172                         rmax = stp->sd_wrq->q_next->q_maxpsz;
4173                         mutex_exit(QLOCK(stp->sd_wrq->q_next));
4174 
4175                         /* Do this processing here as a performance concern */
4176                         if (strmsgsz != 0) {
4177                                 if (rmax == INFPSZ) {
4178                                         rmax = strmsgsz;
4179                                 } else  {
4180                                         rmax = MIN(strmsgsz, rmax);
4181                                 }
4182                         }
4183 
4184                         mutex_enter(QLOCK(wrq));
4185                         stp->sd_qn_minpsz = rmin;
4186                         stp->sd_qn_maxpsz = rmax;
4187                         mutex_exit(QLOCK(wrq));
4188                 }
4189 
4190                 /*
4191                  * Need to update the anchor value if this module is
4192                  * inserted below the anchor point.
4193                  */
4194                 if (stp->sd_anchor != 0) {
4195                         pos = STRUCT_FGET(strmodinsert, pos);
4196                         if (pos >= (stp->sd_pushcnt - stp->sd_anchor))
4197                                 stp->sd_anchor++;
4198                 }
4199 
4200                 strendplumb(stp);
4201                 mutex_exit(&stp->sd_lock);
4202                 return (0);
4203         }
4204 
4205         case _I_REMOVE:
4206         {
4207                 /*
4208                  * To remove a module with a given name in a stream.  The
4209                  * caller of this ioctl needs to provide both the name and
4210                  * the position of the module to be removed.  This eliminates
4211                  * the ambiguity of removal if a module is inserted/pushed
4212                  * multiple times in a stream.  In the first release, only
4213                  * allow privileged user to use this ioctl.
4214                  * Furthermore, the remove is only allowed
4215                  * below an anchor if the zoneid is the same as the zoneid
4216                  * which created the anchor.
4217                  *
4218                  * Note that we do not plan to support this ioctl
4219                  * on pipes in the first release.  We want to learn more
4220                  * about the implications of these ioctls before extending
4221                  * their support.  And we do not think these features are
4222                  * valuable for pipes.
4223                  *
4224                  * Also note that _I_REMOVE cannot be used to remove a
4225                  * driver or the stream head.
4226                  */
4227                 STRUCT_DECL(strmodconf, strmodremove);
4228                 queue_t *q;
4229                 int pos;
4230                 char mod_name[FMNAMESZ + 1];
4231                 boolean_t is_remove;
4232 
4233                 STRUCT_INIT(strmodremove, flag);
4234                 if (stp->sd_flag & STRHUP)
4235                         return (ENXIO);
4236                 if (STRMATED(stp))
4237                         return (EINVAL);
4238                 if ((error = secpolicy_net_config(crp, B_FALSE)) != 0)
4239                         return (error);
4240                 if (stp->sd_anchor != 0 &&
4241                     stp->sd_anchorzone != crgetzoneid(crp))
4242                         return (EINVAL);
4243 
4244                 error = strcopyin((void *)arg, STRUCT_BUF(strmodremove),
4245                     STRUCT_SIZE(strmodremove), copyflag);
4246                 if (error)
4247                         return (error);
4248 
4249                 error = (copyflag & U_TO_K ? copyinstr :
4250                     copystr)(STRUCT_FGETP(strmodremove, mod_name),
4251                     mod_name, FMNAMESZ + 1, NULL);
4252                 if (error)
4253                         return ((error == ENAMETOOLONG) ? EINVAL : EFAULT);
4254 
4255                 if ((error = strstartplumb(stp, flag, cmd)) != 0)
4256                         return (error);
4257 
4258                 /*
4259                  * Match the name of given module to the name of module at
4260                  * the given position.
4261                  */
4262                 pos = STRUCT_FGET(strmodremove, pos);
4263 
4264                 is_remove = (pos != 0);
4265                 for (q = stp->sd_wrq->q_next; SAMESTR(q) && pos > 0;
4266                     q = q->q_next, pos--)
4267                         ;
4268                 if (pos > 0 || !SAMESTR(q) ||
4269                     strcmp(Q2NAME(q), mod_name) != 0) {
4270                         mutex_enter(&stp->sd_lock);
4271                         strendplumb(stp);
4272                         mutex_exit(&stp->sd_lock);
4273                         return (EINVAL);
4274                 }
4275 
4276                 /*
4277                  * If the position is at or below an anchor, then the zoneid
4278                  * must match the zoneid that created the anchor.
4279                  */
4280                 if (stp->sd_anchor != 0) {
4281                         pos = STRUCT_FGET(strmodremove, pos);
4282                         if (pos >= (stp->sd_pushcnt - stp->sd_anchor) &&
4283                             stp->sd_anchorzone != crgetzoneid(crp)) {
4284                                 mutex_enter(&stp->sd_lock);
4285                                 strendplumb(stp);
4286                                 mutex_exit(&stp->sd_lock);
4287                                 return (EPERM);
4288                         }
4289                 }
4290 
4291 
4292                 ASSERT(!(q->q_flag & QREADR));
4293                 qdetach(_RD(q), 1, flag, crp, is_remove);
4294 
4295                 mutex_enter(&stp->sd_lock);
4296 
4297                 /*
4298                  * As a performance concern we are caching the values of
4299                  * q_minpsz and q_maxpsz of the module below the stream
4300                  * head in the stream head.
4301                  */
4302                 if (!is_remove) {
4303                         mutex_enter(QLOCK(wrq->q_next));
4304                         rmin = wrq->q_next->q_minpsz;
4305                         rmax = wrq->q_next->q_maxpsz;
4306                         mutex_exit(QLOCK(wrq->q_next));
4307 
4308                         /* Do this processing here as a performance concern */
4309                         if (strmsgsz != 0) {
4310                                 if (rmax == INFPSZ)
4311                                         rmax = strmsgsz;
4312                                 else  {
4313                                         if (vp->v_type == VFIFO)
4314                                                 rmax = MIN(PIPE_BUF, rmax);
4315                                         else    rmax = MIN(strmsgsz, rmax);
4316                                 }
4317                         }
4318 
4319                         mutex_enter(QLOCK(wrq));
4320                         stp->sd_qn_minpsz = rmin;
4321                         stp->sd_qn_maxpsz = rmax;
4322                         mutex_exit(QLOCK(wrq));
4323                 }
4324 
4325                 /*
4326                  * Need to update the anchor value if this module is removed
4327                  * at or below the anchor point.  If the removed module is at
4328                  * the anchor point, remove the anchor for this stream if
4329                  * there is no module above the anchor point.  Otherwise, if
4330                  * the removed module is below the anchor point, decrement the
4331                  * anchor point by 1.
4332                  */
4333                 if (stp->sd_anchor != 0) {
4334                         pos = STRUCT_FGET(strmodremove, pos);
4335                         if (pos == stp->sd_pushcnt - stp->sd_anchor + 1)
4336                                 stp->sd_anchor = 0;
4337                         else if (pos > (stp->sd_pushcnt - stp->sd_anchor + 1))
4338                                 stp->sd_anchor--;
4339                 }
4340 
4341                 strendplumb(stp);
4342                 mutex_exit(&stp->sd_lock);
4343                 return (0);
4344         }
4345 
4346         case I_ANCHOR:
4347                 /*
4348                  * Set the anchor position on the stream to reside at
4349                  * the top module (in other words, the top module
4350                  * cannot be popped).  Anchors with a FIFO make no
4351                  * obvious sense, so they're not allowed.
4352                  */
4353                 mutex_enter(&stp->sd_lock);
4354 
4355                 if (stp->sd_vnode->v_type == VFIFO) {
4356                         mutex_exit(&stp->sd_lock);
4357                         return (EINVAL);
4358                 }
4359                 /* Only allow the same zoneid to update the anchor */
4360                 if (stp->sd_anchor != 0 &&
4361                     stp->sd_anchorzone != crgetzoneid(crp)) {
4362                         mutex_exit(&stp->sd_lock);
4363                         return (EINVAL);
4364                 }
4365                 stp->sd_anchor = stp->sd_pushcnt;
4366                 stp->sd_anchorzone = crgetzoneid(crp);
4367                 mutex_exit(&stp->sd_lock);
4368                 return (0);
4369 
4370         case I_LOOK:
4371                 /*
4372                  * Get name of first module downstream.
4373                  * If no module, return an error.
4374                  */
4375                 claimstr(wrq);
4376                 if (_SAMESTR(wrq) && wrq->q_next->q_next != NULL) {
4377                         char *name = Q2NAME(wrq->q_next);
4378 
4379                         error = strcopyout(name, (void *)arg, strlen(name) + 1,
4380                             copyflag);
4381                         releasestr(wrq);
4382                         return (error);
4383                 }
4384                 releasestr(wrq);
4385                 return (EINVAL);
4386 
4387         case I_LINK:
4388         case I_PLINK:
4389                 /*
4390                  * Link a multiplexor.
4391                  */
4392                 return (mlink(vp, cmd, (int)arg, crp, rvalp, 0));
4393 
4394         case _I_PLINK_LH:
4395                 /*
4396                  * Link a multiplexor: Call must originate from kernel.
4397                  */
4398                 if (kioctl)
4399                         return (ldi_mlink_lh(vp, cmd, arg, crp, rvalp));
4400 
4401                 return (EINVAL);
4402         case I_UNLINK:
4403         case I_PUNLINK:
4404                 /*
4405                  * Unlink a multiplexor.
4406                  * If arg is -1, unlink all links for which this is the
4407                  * controlling stream.  Otherwise, arg is an index number
4408                  * for a link to be removed.
4409                  */
4410         {
4411                 struct linkinfo *linkp;
4412                 int native_arg = (int)arg;
4413                 int type;
4414                 netstack_t *ns;
4415                 str_stack_t *ss;
4416 
4417                 TRACE_1(TR_FAC_STREAMS_FR,
4418                     TR_I_UNLINK, "I_UNLINK/I_PUNLINK:%p", stp);
4419                 if (vp->v_type == VFIFO) {
4420                         return (EINVAL);
4421                 }
4422                 if (cmd == I_UNLINK)
4423                         type = LINKNORMAL;
4424                 else    /* I_PUNLINK */
4425                         type = LINKPERSIST;
4426                 if (native_arg == 0) {
4427                         return (EINVAL);
4428                 }
4429                 ns = netstack_find_by_cred(crp);
4430                 ASSERT(ns != NULL);
4431                 ss = ns->netstack_str;
4432                 ASSERT(ss != NULL);
4433 
4434                 if (native_arg == MUXID_ALL)
4435                         error = munlinkall(stp, type, crp, rvalp, ss);
4436                 else {
4437                         mutex_enter(&muxifier);
4438                         if (!(linkp = findlinks(stp, (int)arg, type, ss))) {
4439                                 /* invalid user supplied index number */
4440                                 mutex_exit(&muxifier);
4441                                 netstack_rele(ss->ss_netstack);
4442                                 return (EINVAL);
4443                         }
4444                         /* munlink drops the muxifier lock */
4445                         error = munlink(stp, linkp, type, crp, rvalp, ss);
4446                 }
4447                 netstack_rele(ss->ss_netstack);
4448                 return (error);
4449         }
4450 
4451         case I_FLUSH:
4452                 /*
4453                  * send a flush message downstream
4454                  * flush message can indicate
4455                  * FLUSHR - flush read queue
4456                  * FLUSHW - flush write queue
4457                  * FLUSHRW - flush read/write queue
4458                  */
4459                 if (stp->sd_flag & STRHUP)
4460                         return (ENXIO);
4461                 if (arg & ~FLUSHRW)
4462                         return (EINVAL);
4463 
4464                 for (;;) {
4465                         if (putnextctl1(stp->sd_wrq, M_FLUSH, (int)arg)) {
4466                                 break;
4467                         }
4468                         if (error = strwaitbuf(1, BPRI_HI)) {
4469                                 return (error);
4470                         }
4471                 }
4472 
4473                 /*
4474                  * Send down an unsupported ioctl and wait for the nack
4475                  * in order to allow the M_FLUSH to propagate back
4476                  * up to the stream head.
4477                  * Replaces if (qready()) runqueues();
4478                  */
4479                 strioc.ic_cmd = -1;     /* The unsupported ioctl */
4480                 strioc.ic_timout = 0;
4481                 strioc.ic_len = 0;
4482                 strioc.ic_dp = NULL;
4483                 (void) strdoioctl(stp, &strioc, flag, K_TO_K, crp, rvalp);
4484                 *rvalp = 0;
4485                 return (0);
4486 
4487         case I_FLUSHBAND:
4488         {
4489                 struct bandinfo binfo;
4490 
4491                 error = strcopyin((void *)arg, &binfo, sizeof (binfo),
4492                     copyflag);
4493                 if (error)
4494                         return (error);
4495                 if (stp->sd_flag & STRHUP)
4496                         return (ENXIO);
4497                 if (binfo.bi_flag & ~FLUSHRW)
4498                         return (EINVAL);
4499                 while (!(mp = allocb(2, BPRI_HI))) {
4500                         if (error = strwaitbuf(2, BPRI_HI))
4501                                 return (error);
4502                 }
4503                 mp->b_datap->db_type = M_FLUSH;
4504                 *mp->b_wptr++ = binfo.bi_flag | FLUSHBAND;
4505                 *mp->b_wptr++ = binfo.bi_pri;
4506                 putnext(stp->sd_wrq, mp);
4507                 /*
4508                  * Send down an unsupported ioctl and wait for the nack
4509                  * in order to allow the M_FLUSH to propagate back
4510                  * up to the stream head.
4511                  * Replaces if (qready()) runqueues();
4512                  */
4513                 strioc.ic_cmd = -1;     /* The unsupported ioctl */
4514                 strioc.ic_timout = 0;
4515                 strioc.ic_len = 0;
4516                 strioc.ic_dp = NULL;
4517                 (void) strdoioctl(stp, &strioc, flag, K_TO_K, crp, rvalp);
4518                 *rvalp = 0;
4519                 return (0);
4520         }
4521 
4522         case I_SRDOPT:
4523                 /*
4524                  * Set read options
4525                  *
4526                  * RNORM - default stream mode
4527                  * RMSGN - message no discard
4528                  * RMSGD - message discard
4529                  * RPROTNORM - fail read with EBADMSG for M_[PC]PROTOs
4530                  * RPROTDAT - convert M_[PC]PROTOs to M_DATAs
4531                  * RPROTDIS - discard M_[PC]PROTOs and retain M_DATAs
4532                  */
4533                 if (arg & ~(RMODEMASK | RPROTMASK))
4534                         return (EINVAL);
4535 
4536                 if ((arg & (RMSGD|RMSGN)) == (RMSGD|RMSGN))
4537                         return (EINVAL);
4538 
4539                 mutex_enter(&stp->sd_lock);
4540                 switch (arg & RMODEMASK) {
4541                 case RNORM:
4542                         stp->sd_read_opt &= ~(RD_MSGDIS | RD_MSGNODIS);
4543                         break;
4544                 case RMSGD:
4545                         stp->sd_read_opt = (stp->sd_read_opt & ~RD_MSGNODIS) |
4546                             RD_MSGDIS;
4547                         break;
4548                 case RMSGN:
4549                         stp->sd_read_opt = (stp->sd_read_opt & ~RD_MSGDIS) |
4550                             RD_MSGNODIS;
4551                         break;
4552                 }
4553 
4554                 switch (arg & RPROTMASK) {
4555                 case RPROTNORM:
4556                         stp->sd_read_opt &= ~(RD_PROTDAT | RD_PROTDIS);
4557                         break;
4558 
4559                 case RPROTDAT:
4560                         stp->sd_read_opt = ((stp->sd_read_opt & ~RD_PROTDIS) |
4561                             RD_PROTDAT);
4562                         break;
4563 
4564                 case RPROTDIS:
4565                         stp->sd_read_opt = ((stp->sd_read_opt & ~RD_PROTDAT) |
4566                             RD_PROTDIS);
4567                         break;
4568                 }
4569                 mutex_exit(&stp->sd_lock);
4570                 return (0);
4571 
4572         case I_GRDOPT:
4573                 /*
4574                  * Get read option and return the value
4575                  * to spot pointed to by arg
4576                  */
4577         {
4578                 int rdopt;
4579 
4580                 rdopt = ((stp->sd_read_opt & RD_MSGDIS) ? RMSGD :
4581                     ((stp->sd_read_opt & RD_MSGNODIS) ? RMSGN : RNORM));
4582                 rdopt |= ((stp->sd_read_opt & RD_PROTDAT) ? RPROTDAT :
4583                     ((stp->sd_read_opt & RD_PROTDIS) ? RPROTDIS : RPROTNORM));
4584 
4585                 return (strcopyout(&rdopt, (void *)arg, sizeof (int),
4586                     copyflag));
4587         }
4588 
4589         case I_SERROPT:
4590                 /*
4591                  * Set error options
4592                  *
4593                  * RERRNORM - persistent read errors
4594                  * RERRNONPERSIST - non-persistent read errors
4595                  * WERRNORM - persistent write errors
4596                  * WERRNONPERSIST - non-persistent write errors
4597                  */
4598                 if (arg & ~(RERRMASK | WERRMASK))
4599                         return (EINVAL);
4600 
4601                 mutex_enter(&stp->sd_lock);
4602                 switch (arg & RERRMASK) {
4603                 case RERRNORM:
4604                         stp->sd_flag &= ~STRDERRNONPERSIST;
4605                         break;
4606                 case RERRNONPERSIST:
4607                         stp->sd_flag |= STRDERRNONPERSIST;
4608                         break;
4609                 }
4610                 switch (arg & WERRMASK) {
4611                 case WERRNORM:
4612                         stp->sd_flag &= ~STWRERRNONPERSIST;
4613                         break;
4614                 case WERRNONPERSIST:
4615                         stp->sd_flag |= STWRERRNONPERSIST;
4616                         break;
4617                 }
4618                 mutex_exit(&stp->sd_lock);
4619                 return (0);
4620 
4621         case I_GERROPT:
4622                 /*
4623                  * Get error option and return the value
4624                  * to spot pointed to by arg
4625                  */
4626         {
4627                 int erropt = 0;
4628 
4629                 erropt |= (stp->sd_flag & STRDERRNONPERSIST) ? RERRNONPERSIST :
4630                     RERRNORM;
4631                 erropt |= (stp->sd_flag & STWRERRNONPERSIST) ? WERRNONPERSIST :
4632                     WERRNORM;
4633                 return (strcopyout(&erropt, (void *)arg, sizeof (int),
4634                     copyflag));
4635         }
4636 
4637         case I_SETSIG:
4638                 /*
4639                  * Register the calling proc to receive the SIGPOLL
4640                  * signal based on the events given in arg.  If
4641                  * arg is zero, remove the proc from register list.
4642                  */
4643         {
4644                 strsig_t *ssp, *pssp;
4645                 struct pid *pidp;
4646 
4647                 pssp = NULL;
4648                 pidp = curproc->p_pidp;
4649                 /*
4650                  * Hold sd_lock to prevent traversal of sd_siglist while
4651                  * it is modified.
4652                  */
4653                 mutex_enter(&stp->sd_lock);
4654                 for (ssp = stp->sd_siglist; ssp && (ssp->ss_pidp != pidp);
4655                     pssp = ssp, ssp = ssp->ss_next)
4656                         ;
4657 
4658                 if (arg) {
4659                         if (arg & ~(S_INPUT|S_HIPRI|S_MSG|S_HANGUP|S_ERROR|
4660                             S_RDNORM|S_WRNORM|S_RDBAND|S_WRBAND|S_BANDURG)) {
4661                                 mutex_exit(&stp->sd_lock);
4662                                 return (EINVAL);
4663                         }
4664                         if ((arg & S_BANDURG) && !(arg & S_RDBAND)) {
4665                                 mutex_exit(&stp->sd_lock);
4666                                 return (EINVAL);
4667                         }
4668 
4669                         /*
4670                          * If proc not already registered, add it
4671                          * to list.
4672                          */
4673                         if (!ssp) {
4674                                 ssp = kmem_alloc(sizeof (strsig_t), KM_SLEEP);
4675                                 ssp->ss_pidp = pidp;
4676                                 ssp->ss_pid = pidp->pid_id;
4677                                 ssp->ss_next = NULL;
4678                                 if (pssp)
4679                                         pssp->ss_next = ssp;
4680                                 else
4681                                         stp->sd_siglist = ssp;
4682                                 mutex_enter(&pidlock);
4683                                 PID_HOLD(pidp);
4684                                 mutex_exit(&pidlock);
4685                         }
4686 
4687                         /*
4688                          * Set events.
4689                          */
4690                         ssp->ss_events = (int)arg;
4691                 } else {
4692                         /*
4693                          * Remove proc from register list.
4694                          */
4695                         if (ssp) {
4696                                 mutex_enter(&pidlock);
4697                                 PID_RELE(pidp);
4698                                 mutex_exit(&pidlock);
4699                                 if (pssp)
4700                                         pssp->ss_next = ssp->ss_next;
4701                                 else
4702                                         stp->sd_siglist = ssp->ss_next;
4703                                 kmem_free(ssp, sizeof (strsig_t));
4704                         } else {
4705                                 mutex_exit(&stp->sd_lock);
4706                                 return (EINVAL);
4707                         }
4708                 }
4709 
4710                 /*
4711                  * Recalculate OR of sig events.
4712                  */
4713                 stp->sd_sigflags = 0;
4714                 for (ssp = stp->sd_siglist; ssp; ssp = ssp->ss_next)
4715                         stp->sd_sigflags |= ssp->ss_events;
4716                 mutex_exit(&stp->sd_lock);
4717                 return (0);
4718         }
4719 
4720         case I_GETSIG:
4721                 /*
4722                  * Return (in arg) the current registration of events
4723                  * for which the calling proc is to be signaled.
4724                  */
4725         {
4726                 struct strsig *ssp;
4727                 struct pid  *pidp;
4728 
4729                 pidp = curproc->p_pidp;
4730                 mutex_enter(&stp->sd_lock);
4731                 for (ssp = stp->sd_siglist; ssp; ssp = ssp->ss_next)
4732                         if (ssp->ss_pidp == pidp) {
4733                                 error = strcopyout(&ssp->ss_events, (void *)arg,
4734                                     sizeof (int), copyflag);
4735                                 mutex_exit(&stp->sd_lock);
4736                                 return (error);
4737                         }
4738                 mutex_exit(&stp->sd_lock);
4739                 return (EINVAL);
4740         }
4741 
4742         case I_ESETSIG:
4743                 /*
4744                  * Register the ss_pid to receive the SIGPOLL
4745                  * signal based on the events is ss_events arg.  If
4746                  * ss_events is zero, remove the proc from register list.
4747                  */
4748         {
4749                 struct strsig *ssp, *pssp;
4750                 struct proc *proc;
4751                 struct pid  *pidp;
4752                 pid_t pid;
4753                 struct strsigset ss;
4754 
4755                 error = strcopyin((void *)arg, &ss, sizeof (ss), copyflag);
4756                 if (error)
4757                         return (error);
4758 
4759                 pid = ss.ss_pid;
4760 
4761                 if (ss.ss_events != 0) {
4762                         /*
4763                          * Permissions check by sending signal 0.
4764                          * Note that when kill fails it does a set_errno
4765                          * causing the system call to fail.
4766                          */
4767                         error = kill(pid, 0);
4768                         if (error) {
4769                                 return (error);
4770                         }
4771                 }
4772                 mutex_enter(&pidlock);
4773                 if (pid == 0)
4774                         proc = curproc;
4775                 else if (pid < 0)
4776                         proc = pgfind(-pid);
4777                 else
4778                         proc = prfind(pid);
4779                 if (proc == NULL) {
4780                         mutex_exit(&pidlock);
4781                         return (ESRCH);
4782                 }
4783                 if (pid < 0)
4784                         pidp = proc->p_pgidp;
4785                 else
4786                         pidp = proc->p_pidp;
4787                 ASSERT(pidp);
4788                 /*
4789                  * Get a hold on the pid structure while referencing it.
4790                  * There is a separate PID_HOLD should it be inserted
4791                  * in the list below.
4792                  */
4793                 PID_HOLD(pidp);
4794                 mutex_exit(&pidlock);
4795 
4796                 pssp = NULL;
4797                 /*
4798                  * Hold sd_lock to prevent traversal of sd_siglist while
4799                  * it is modified.
4800                  */
4801                 mutex_enter(&stp->sd_lock);
4802                 for (ssp = stp->sd_siglist; ssp && (ssp->ss_pid != pid);
4803                     pssp = ssp, ssp = ssp->ss_next)
4804                         ;
4805 
4806                 if (ss.ss_events) {
4807                         if (ss.ss_events &
4808                             ~(S_INPUT|S_HIPRI|S_MSG|S_HANGUP|S_ERROR|
4809                             S_RDNORM|S_WRNORM|S_RDBAND|S_WRBAND|S_BANDURG)) {
4810                                 mutex_exit(&stp->sd_lock);
4811                                 mutex_enter(&pidlock);
4812                                 PID_RELE(pidp);
4813                                 mutex_exit(&pidlock);
4814                                 return (EINVAL);
4815                         }
4816                         if ((ss.ss_events & S_BANDURG) &&
4817                             !(ss.ss_events & S_RDBAND)) {
4818                                 mutex_exit(&stp->sd_lock);
4819                                 mutex_enter(&pidlock);
4820                                 PID_RELE(pidp);
4821                                 mutex_exit(&pidlock);
4822                                 return (EINVAL);
4823                         }
4824 
4825                         /*
4826                          * If proc not already registered, add it
4827                          * to list.
4828                          */
4829                         if (!ssp) {
4830                                 ssp = kmem_alloc(sizeof (strsig_t), KM_SLEEP);
4831                                 ssp->ss_pidp = pidp;
4832                                 ssp->ss_pid = pid;
4833                                 ssp->ss_next = NULL;
4834                                 if (pssp)
4835                                         pssp->ss_next = ssp;
4836                                 else
4837                                         stp->sd_siglist = ssp;
4838                                 mutex_enter(&pidlock);
4839                                 PID_HOLD(pidp);
4840                                 mutex_exit(&pidlock);
4841                         }
4842 
4843                         /*
4844                          * Set events.
4845                          */
4846                         ssp->ss_events = ss.ss_events;
4847                 } else {
4848                         /*
4849                          * Remove proc from register list.
4850                          */
4851                         if (ssp) {
4852                                 mutex_enter(&pidlock);
4853                                 PID_RELE(pidp);
4854                                 mutex_exit(&pidlock);
4855                                 if (pssp)
4856                                         pssp->ss_next = ssp->ss_next;
4857                                 else
4858                                         stp->sd_siglist = ssp->ss_next;
4859                                 kmem_free(ssp, sizeof (strsig_t));
4860                         } else {
4861                                 mutex_exit(&stp->sd_lock);
4862                                 mutex_enter(&pidlock);
4863                                 PID_RELE(pidp);
4864                                 mutex_exit(&pidlock);
4865                                 return (EINVAL);
4866                         }
4867                 }
4868 
4869                 /*
4870                  * Recalculate OR of sig events.
4871                  */
4872                 stp->sd_sigflags = 0;
4873                 for (ssp = stp->sd_siglist; ssp; ssp = ssp->ss_next)
4874                         stp->sd_sigflags |= ssp->ss_events;
4875                 mutex_exit(&stp->sd_lock);
4876                 mutex_enter(&pidlock);
4877                 PID_RELE(pidp);
4878                 mutex_exit(&pidlock);
4879                 return (0);
4880         }
4881 
4882         case I_EGETSIG:
4883                 /*
4884                  * Return (in arg) the current registration of events
4885                  * for which the calling proc is to be signaled.
4886                  */
4887         {
4888                 struct strsig *ssp;
4889                 struct proc *proc;
4890                 pid_t pid;
4891                 struct pid  *pidp;
4892                 struct strsigset ss;
4893 
4894                 error = strcopyin((void *)arg, &ss, sizeof (ss), copyflag);
4895                 if (error)
4896                         return (error);
4897 
4898                 pid = ss.ss_pid;
4899                 mutex_enter(&pidlock);
4900                 if (pid == 0)
4901                         proc = curproc;
4902                 else if (pid < 0)
4903                         proc = pgfind(-pid);
4904                 else
4905                         proc = prfind(pid);
4906                 if (proc == NULL) {
4907                         mutex_exit(&pidlock);
4908                         return (ESRCH);
4909                 }
4910                 if (pid < 0)
4911                         pidp = proc->p_pgidp;
4912                 else
4913                         pidp = proc->p_pidp;
4914 
4915                 /* Prevent the pidp from being reassigned */
4916                 PID_HOLD(pidp);
4917                 mutex_exit(&pidlock);
4918 
4919                 mutex_enter(&stp->sd_lock);
4920                 for (ssp = stp->sd_siglist; ssp; ssp = ssp->ss_next)
4921                         if (ssp->ss_pid == pid) {
4922                                 ss.ss_pid = ssp->ss_pid;
4923                                 ss.ss_events = ssp->ss_events;
4924                                 error = strcopyout(&ss, (void *)arg,
4925                                     sizeof (struct strsigset), copyflag);
4926                                 mutex_exit(&stp->sd_lock);
4927                                 mutex_enter(&pidlock);
4928                                 PID_RELE(pidp);
4929                                 mutex_exit(&pidlock);
4930                                 return (error);
4931                         }
4932                 mutex_exit(&stp->sd_lock);
4933                 mutex_enter(&pidlock);
4934                 PID_RELE(pidp);
4935                 mutex_exit(&pidlock);
4936                 return (EINVAL);
4937         }
4938 
4939         case I_PEEK:
4940         {
4941                 STRUCT_DECL(strpeek, strpeek);
4942                 size_t n;
4943                 mblk_t *fmp, *tmp_mp = NULL;
4944 
4945                 STRUCT_INIT(strpeek, flag);
4946 
4947                 error = strcopyin((void *)arg, STRUCT_BUF(strpeek),
4948                     STRUCT_SIZE(strpeek), copyflag);
4949                 if (error)
4950                         return (error);
4951 
4952                 mutex_enter(QLOCK(rdq));
4953                 /*
4954                  * Skip the invalid messages
4955                  */
4956                 for (mp = rdq->q_first; mp != NULL; mp = mp->b_next)
4957                         if (mp->b_datap->db_type != M_SIG)
4958                                 break;
4959 
4960                 /*
4961                  * If user has requested to peek at a high priority message
4962                  * and first message is not, return 0
4963                  */
4964                 if (mp != NULL) {
4965                         if ((STRUCT_FGET(strpeek, flags) & RS_HIPRI) &&
4966                             queclass(mp) == QNORM) {
4967                                 *rvalp = 0;
4968                                 mutex_exit(QLOCK(rdq));
4969                                 return (0);
4970                         }
4971                 } else if (stp->sd_struiordq == NULL ||
4972                     (STRUCT_FGET(strpeek, flags) & RS_HIPRI)) {
4973                         /*
4974                          * No mblks to look at at the streamhead and
4975                          * 1). This isn't a synch stream or
4976                          * 2). This is a synch stream but caller wants high
4977                          *      priority messages which is not supported by
4978                          *      the synch stream. (it only supports QNORM)
4979                          */
4980                         *rvalp = 0;
4981                         mutex_exit(QLOCK(rdq));
4982                         return (0);
4983                 }
4984 
4985                 fmp = mp;
4986 
4987                 if (mp && mp->b_datap->db_type == M_PASSFP) {
4988                         mutex_exit(QLOCK(rdq));
4989                         return (EBADMSG);
4990                 }
4991 
4992                 ASSERT(mp == NULL || mp->b_datap->db_type == M_PCPROTO ||
4993                     mp->b_datap->db_type == M_PROTO ||
4994                     mp->b_datap->db_type == M_DATA);
4995 
4996                 if (mp && mp->b_datap->db_type == M_PCPROTO) {
4997                         STRUCT_FSET(strpeek, flags, RS_HIPRI);
4998                 } else {
4999                         STRUCT_FSET(strpeek, flags, 0);
5000                 }
5001 
5002 
5003                 if (mp && ((tmp_mp = dupmsg(mp)) == NULL)) {
5004                         mutex_exit(QLOCK(rdq));
5005                         return (ENOSR);
5006                 }
5007                 mutex_exit(QLOCK(rdq));
5008 
5009                 /*
5010                  * set mp = tmp_mp, so that I_PEEK processing can continue.
5011                  * tmp_mp is used to free the dup'd message.
5012                  */
5013                 mp = tmp_mp;
5014 
5015                 uio.uio_fmode = 0;
5016                 uio.uio_extflg = UIO_COPY_CACHED;
5017                 uio.uio_segflg = (copyflag == U_TO_K) ? UIO_USERSPACE :
5018                     UIO_SYSSPACE;
5019                 uio.uio_limit = 0;
5020                 /*
5021                  * First process PROTO blocks, if any.
5022                  * If user doesn't want to get ctl info by setting maxlen <= 0,
5023                  * then set len to -1/0 and skip control blocks part.
5024                  */
5025                 if (STRUCT_FGET(strpeek, ctlbuf.maxlen) < 0)
5026                         STRUCT_FSET(strpeek, ctlbuf.len, -1);
5027                 else if (STRUCT_FGET(strpeek, ctlbuf.maxlen) == 0)
5028                         STRUCT_FSET(strpeek, ctlbuf.len, 0);
5029                 else {
5030                         int     ctl_part = 0;
5031 
5032                         iov.iov_base = STRUCT_FGETP(strpeek, ctlbuf.buf);
5033                         iov.iov_len = STRUCT_FGET(strpeek, ctlbuf.maxlen);
5034                         uio.uio_iov = &iov;
5035                         uio.uio_resid = iov.iov_len;
5036                         uio.uio_loffset = 0;
5037                         uio.uio_iovcnt = 1;
5038                         while (mp && mp->b_datap->db_type != M_DATA &&
5039                             uio.uio_resid >= 0) {
5040                                 ASSERT(STRUCT_FGET(strpeek, flags) == 0 ?
5041                                     mp->b_datap->db_type == M_PROTO :
5042                                     mp->b_datap->db_type == M_PCPROTO);
5043 
5044                                 if ((n = MIN(uio.uio_resid,
5045                                     mp->b_wptr - mp->b_rptr)) != 0 &&
5046                                     (error = uiomove((char *)mp->b_rptr, n,
5047                                     UIO_READ, &uio)) != 0) {
5048                                         freemsg(tmp_mp);
5049                                         return (error);
5050                                 }
5051                                 ctl_part = 1;
5052                                 mp = mp->b_cont;
5053                         }
5054                         /* No ctl message */
5055                         if (ctl_part == 0)
5056                                 STRUCT_FSET(strpeek, ctlbuf.len, -1);
5057                         else
5058                                 STRUCT_FSET(strpeek, ctlbuf.len,
5059                                     STRUCT_FGET(strpeek, ctlbuf.maxlen) -
5060                                     uio.uio_resid);
5061                 }
5062 
5063                 /*
5064                  * Now process DATA blocks, if any.
5065                  * If user doesn't want to get data info by setting maxlen <= 0,
5066                  * then set len to -1/0 and skip data blocks part.
5067                  */
5068                 if (STRUCT_FGET(strpeek, databuf.maxlen) < 0)
5069                         STRUCT_FSET(strpeek, databuf.len, -1);
5070                 else if (STRUCT_FGET(strpeek, databuf.maxlen) == 0)
5071                         STRUCT_FSET(strpeek, databuf.len, 0);
5072                 else {
5073                         int     data_part = 0;
5074 
5075                         iov.iov_base = STRUCT_FGETP(strpeek, databuf.buf);
5076                         iov.iov_len = STRUCT_FGET(strpeek, databuf.maxlen);
5077                         uio.uio_iov = &iov;
5078                         uio.uio_resid = iov.iov_len;
5079                         uio.uio_loffset = 0;
5080                         uio.uio_iovcnt = 1;
5081                         while (mp && uio.uio_resid) {
5082                                 if (mp->b_datap->db_type == M_DATA) {
5083                                         if ((n = MIN(uio.uio_resid,
5084                                             mp->b_wptr - mp->b_rptr)) != 0 &&
5085                                             (error = uiomove((char *)mp->b_rptr,
5086                                             n, UIO_READ, &uio)) != 0) {
5087                                                 freemsg(tmp_mp);
5088                                                 return (error);
5089                                         }
5090                                         data_part = 1;
5091                                 }
5092                                 ASSERT(data_part == 0 ||
5093                                     mp->b_datap->db_type == M_DATA);
5094                                 mp = mp->b_cont;
5095                         }
5096                         /* No data message */
5097                         if (data_part == 0)
5098                                 STRUCT_FSET(strpeek, databuf.len, -1);
5099                         else
5100                                 STRUCT_FSET(strpeek, databuf.len,
5101                                     STRUCT_FGET(strpeek, databuf.maxlen) -
5102                                     uio.uio_resid);
5103                 }
5104                 freemsg(tmp_mp);
5105 
5106                 /*
5107                  * It is a synch stream and user wants to get
5108                  * data (maxlen > 0).
5109                  * uio setup is done by the codes that process DATA
5110                  * blocks above.
5111                  */
5112                 if ((fmp == NULL) && STRUCT_FGET(strpeek, databuf.maxlen) > 0) {
5113                         infod_t infod;
5114 
5115                         infod.d_cmd = INFOD_COPYOUT;
5116                         infod.d_res = 0;
5117                         infod.d_uiop = &uio;
5118                         error = infonext(rdq, &infod);
5119                         if (error == EINVAL || error == EBUSY)
5120                                 error = 0;
5121                         if (error)
5122                                 return (error);
5123                         STRUCT_FSET(strpeek, databuf.len, STRUCT_FGET(strpeek,
5124                             databuf.maxlen) - uio.uio_resid);
5125                         if (STRUCT_FGET(strpeek, databuf.len) == 0) {
5126                                 /*
5127                                  * No data found by the infonext().
5128                                  */
5129                                 STRUCT_FSET(strpeek, databuf.len, -1);
5130                         }
5131                 }
5132                 error = strcopyout(STRUCT_BUF(strpeek), (void *)arg,
5133                     STRUCT_SIZE(strpeek), copyflag);
5134                 if (error) {
5135                         return (error);
5136                 }
5137                 /*
5138                  * If there is no message retrieved, set return code to 0
5139                  * otherwise, set it to 1.
5140                  */
5141                 if (STRUCT_FGET(strpeek, ctlbuf.len) == -1 &&
5142                     STRUCT_FGET(strpeek, databuf.len) == -1)
5143                         *rvalp = 0;
5144                 else
5145                         *rvalp = 1;
5146                 return (0);
5147         }
5148 
5149         case I_FDINSERT:
5150         {
5151                 STRUCT_DECL(strfdinsert, strfdinsert);
5152                 struct file *resftp;
5153                 struct stdata *resstp;
5154                 t_uscalar_t     ival;
5155                 ssize_t msgsize;
5156                 struct strbuf mctl;
5157 
5158                 STRUCT_INIT(strfdinsert, flag);
5159                 if (stp->sd_flag & STRHUP)
5160                         return (ENXIO);
5161                 /*
5162                  * STRDERR, STWRERR and STPLEX tested above.
5163                  */
5164                 error = strcopyin((void *)arg, STRUCT_BUF(strfdinsert),
5165                     STRUCT_SIZE(strfdinsert), copyflag);
5166                 if (error)
5167                         return (error);
5168 
5169                 if (STRUCT_FGET(strfdinsert, offset) < 0 ||
5170                     (STRUCT_FGET(strfdinsert, offset) %
5171                     sizeof (t_uscalar_t)) != 0)
5172                         return (EINVAL);
5173                 if ((resftp = getf(STRUCT_FGET(strfdinsert, fildes))) != NULL) {
5174                         if ((resstp = resftp->f_vnode->v_stream) == NULL) {
5175                                 releasef(STRUCT_FGET(strfdinsert, fildes));
5176                                 return (EINVAL);
5177                         }
5178                 } else
5179                         return (EINVAL);
5180 
5181                 mutex_enter(&resstp->sd_lock);
5182                 if (resstp->sd_flag & (STRDERR|STWRERR|STRHUP|STPLEX)) {
5183                         error = strgeterr(resstp,
5184                             STRDERR|STWRERR|STRHUP|STPLEX, 0);
5185                         if (error != 0) {
5186                                 mutex_exit(&resstp->sd_lock);
5187                                 releasef(STRUCT_FGET(strfdinsert, fildes));
5188                                 return (error);
5189                         }
5190                 }
5191                 mutex_exit(&resstp->sd_lock);
5192 
5193 #ifdef  _ILP32
5194                 {
5195                         queue_t *q;
5196                         queue_t *mate = NULL;
5197 
5198                         /* get read queue of stream terminus */
5199                         claimstr(resstp->sd_wrq);
5200                         for (q = resstp->sd_wrq->q_next; q->q_next != NULL;
5201                             q = q->q_next)
5202                                 if (!STRMATED(resstp) && STREAM(q) != resstp &&
5203                                     mate == NULL) {
5204                                         ASSERT(q->q_qinfo->qi_srvp);
5205                                         ASSERT(_OTHERQ(q)->q_qinfo->qi_srvp);
5206                                         claimstr(q);
5207                                         mate = q;
5208                                 }
5209                         q = _RD(q);
5210                         if (mate)
5211                                 releasestr(mate);
5212                         releasestr(resstp->sd_wrq);
5213                         ival = (t_uscalar_t)q;
5214                 }
5215 #else
5216                 ival = (t_uscalar_t)getminor(resftp->f_vnode->v_rdev);
5217 #endif  /* _ILP32 */
5218 
5219                 if (STRUCT_FGET(strfdinsert, ctlbuf.len) <
5220                     STRUCT_FGET(strfdinsert, offset) + sizeof (t_uscalar_t)) {
5221                         releasef(STRUCT_FGET(strfdinsert, fildes));
5222                         return (EINVAL);
5223                 }
5224 
5225                 /*
5226                  * Check for legal flag value.
5227                  */
5228                 if (STRUCT_FGET(strfdinsert, flags) & ~RS_HIPRI) {
5229                         releasef(STRUCT_FGET(strfdinsert, fildes));
5230                         return (EINVAL);
5231                 }
5232 
5233                 /* get these values from those cached in the stream head */
5234                 mutex_enter(QLOCK(stp->sd_wrq));
5235                 rmin = stp->sd_qn_minpsz;
5236                 rmax = stp->sd_qn_maxpsz;
5237                 mutex_exit(QLOCK(stp->sd_wrq));
5238 
5239                 /*
5240                  * Make sure ctl and data sizes together fall within
5241                  * the limits of the max and min receive packet sizes
5242                  * and do not exceed system limit.  A negative data
5243                  * length means that no data part is to be sent.
5244                  */
5245                 ASSERT((rmax >= 0) || (rmax == INFPSZ));
5246                 if (rmax == 0) {
5247                         releasef(STRUCT_FGET(strfdinsert, fildes));
5248                         return (ERANGE);
5249                 }
5250                 if ((msgsize = STRUCT_FGET(strfdinsert, databuf.len)) < 0)
5251                         msgsize = 0;
5252                 if ((msgsize < rmin) ||
5253                     ((msgsize > rmax) && (rmax != INFPSZ)) ||
5254                     (STRUCT_FGET(strfdinsert, ctlbuf.len) > strctlsz)) {
5255                         releasef(STRUCT_FGET(strfdinsert, fildes));
5256                         return (ERANGE);
5257                 }
5258 
5259                 mutex_enter(&stp->sd_lock);
5260                 while (!(STRUCT_FGET(strfdinsert, flags) & RS_HIPRI) &&
5261                     !canputnext(stp->sd_wrq)) {
5262                         if ((error = strwaitq(stp, WRITEWAIT, (ssize_t)0,
5263                             flag, -1, &done)) != 0 || done) {
5264                                 mutex_exit(&stp->sd_lock);
5265                                 releasef(STRUCT_FGET(strfdinsert, fildes));
5266                                 return (error);
5267                         }
5268                         if ((error = i_straccess(stp, access)) != 0) {
5269                                 mutex_exit(&stp->sd_lock);
5270                                 releasef(
5271                                     STRUCT_FGET(strfdinsert, fildes));
5272                                 return (error);
5273                         }
5274                 }
5275                 mutex_exit(&stp->sd_lock);
5276 
5277                 /*
5278                  * Copy strfdinsert.ctlbuf into native form of
5279                  * ctlbuf to pass down into strmakemsg().
5280                  */
5281                 mctl.maxlen = STRUCT_FGET(strfdinsert, ctlbuf.maxlen);
5282                 mctl.len = STRUCT_FGET(strfdinsert, ctlbuf.len);
5283                 mctl.buf = STRUCT_FGETP(strfdinsert, ctlbuf.buf);
5284 
5285                 iov.iov_base = STRUCT_FGETP(strfdinsert, databuf.buf);
5286                 iov.iov_len = STRUCT_FGET(strfdinsert, databuf.len);
5287                 uio.uio_iov = &iov;
5288                 uio.uio_iovcnt = 1;
5289                 uio.uio_loffset = 0;
5290                 uio.uio_segflg = (copyflag == U_TO_K) ? UIO_USERSPACE :
5291                     UIO_SYSSPACE;
5292                 uio.uio_fmode = 0;
5293                 uio.uio_extflg = UIO_COPY_CACHED;
5294                 uio.uio_resid = iov.iov_len;
5295                 if ((error = strmakemsg(&mctl,
5296                     &msgsize, &uio, stp,
5297                     STRUCT_FGET(strfdinsert, flags), &mp)) != 0 || !mp) {
5298                         STRUCT_FSET(strfdinsert, databuf.len, msgsize);
5299                         releasef(STRUCT_FGET(strfdinsert, fildes));
5300                         return (error);
5301                 }
5302 
5303                 STRUCT_FSET(strfdinsert, databuf.len, msgsize);
5304 
5305                 /*
5306                  * Place the possibly reencoded queue pointer 'offset' bytes
5307                  * from the start of the control portion of the message.
5308                  */
5309                 *((t_uscalar_t *)(mp->b_rptr +
5310                     STRUCT_FGET(strfdinsert, offset))) = ival;
5311 
5312                 /*
5313                  * Put message downstream.
5314                  */
5315                 stream_willservice(stp);
5316                 putnext(stp->sd_wrq, mp);
5317                 stream_runservice(stp);
5318                 releasef(STRUCT_FGET(strfdinsert, fildes));
5319                 return (error);
5320         }
5321 
5322         case I_SENDFD:
5323         {
5324                 struct file *fp;
5325 
5326                 if ((fp = getf((int)arg)) == NULL)
5327                         return (EBADF);
5328                 error = do_sendfp(stp, fp, crp);
5329                 if (auditing) {
5330                         audit_fdsend((int)arg, fp, error);
5331                 }
5332                 releasef((int)arg);
5333                 return (error);
5334         }
5335 
5336         case I_RECVFD:
5337         case I_E_RECVFD:
5338         {
5339                 struct k_strrecvfd *srf;
5340                 int i, fd;
5341 
5342                 mutex_enter(&stp->sd_lock);
5343                 while (!(mp = getq(rdq))) {
5344                         if (stp->sd_flag & (STRHUP|STREOF)) {
5345                                 mutex_exit(&stp->sd_lock);
5346                                 return (ENXIO);
5347                         }
5348                         if ((error = strwaitq(stp, GETWAIT, (ssize_t)0,
5349                             flag, -1, &done)) != 0 || done) {
5350                                 mutex_exit(&stp->sd_lock);
5351                                 return (error);
5352                         }
5353                         if ((error = i_straccess(stp, access)) != 0) {
5354                                 mutex_exit(&stp->sd_lock);
5355                                 return (error);
5356                         }
5357                 }
5358                 if (mp->b_datap->db_type != M_PASSFP) {
5359                         putback(stp, rdq, mp, mp->b_band);
5360                         mutex_exit(&stp->sd_lock);
5361                         return (EBADMSG);
5362                 }
5363                 mutex_exit(&stp->sd_lock);
5364 
5365                 srf = (struct k_strrecvfd *)mp->b_rptr;
5366                 if ((fd = ufalloc(0)) == -1) {
5367                         mutex_enter(&stp->sd_lock);
5368                         putback(stp, rdq, mp, mp->b_band);
5369                         mutex_exit(&stp->sd_lock);
5370                         return (EMFILE);
5371                 }
5372                 if (cmd == I_RECVFD) {
5373                         struct o_strrecvfd      ostrfd;
5374 
5375                         /* check to see if uid/gid values are too large. */
5376 
5377                         if (srf->uid > (o_uid_t)USHRT_MAX ||
5378                             srf->gid > (o_gid_t)USHRT_MAX) {
5379                                 mutex_enter(&stp->sd_lock);
5380                                 putback(stp, rdq, mp, mp->b_band);
5381                                 mutex_exit(&stp->sd_lock);
5382                                 setf(fd, NULL); /* release fd entry */
5383                                 return (EOVERFLOW);
5384                         }
5385 
5386                         ostrfd.fd = fd;
5387                         ostrfd.uid = (o_uid_t)srf->uid;
5388                         ostrfd.gid = (o_gid_t)srf->gid;
5389 
5390                         /* Null the filler bits */
5391                         for (i = 0; i < 8; i++)
5392                                 ostrfd.fill[i] = 0;
5393 
5394                         error = strcopyout(&ostrfd, (void *)arg,
5395                             sizeof (struct o_strrecvfd), copyflag);
5396                 } else {                /* I_E_RECVFD */
5397                         struct strrecvfd        strfd;
5398 
5399                         strfd.fd = fd;
5400                         strfd.uid = srf->uid;
5401                         strfd.gid = srf->gid;
5402 
5403                         /* null the filler bits */
5404                         for (i = 0; i < 8; i++)
5405                                 strfd.fill[i] = 0;
5406 
5407                         error = strcopyout(&strfd, (void *)arg,
5408                             sizeof (struct strrecvfd), copyflag);
5409                 }
5410 
5411                 if (error) {
5412                         setf(fd, NULL); /* release fd entry */
5413                         mutex_enter(&stp->sd_lock);
5414                         putback(stp, rdq, mp, mp->b_band);
5415                         mutex_exit(&stp->sd_lock);
5416                         return (error);
5417                 }
5418                 if (auditing) {
5419                         audit_fdrecv(fd, srf->fp);
5420                 }
5421 
5422                 /*
5423                  * Always increment f_count since the freemsg() below will
5424                  * always call free_passfp() which performs a closef().
5425                  */
5426                 mutex_enter(&srf->fp->f_tlock);
5427                 srf->fp->f_count++;
5428                 mutex_exit(&srf->fp->f_tlock);
5429                 setf(fd, srf->fp);
5430                 freemsg(mp);
5431                 return (0);
5432         }
5433 
5434         case I_SWROPT:
5435                 /*
5436                  * Set/clear the write options. arg is a bit
5437                  * mask with any of the following bits set...
5438                  *      SNDZERO - send zero length message
5439                  *      SNDPIPE - send sigpipe to process if
5440                  *              sd_werror is set and process is
5441                  *              doing a write or putmsg.
5442                  * The new stream head write options should reflect
5443                  * what is in arg.
5444                  */
5445                 if (arg & ~(SNDZERO|SNDPIPE))
5446                         return (EINVAL);
5447 
5448                 mutex_enter(&stp->sd_lock);
5449                 stp->sd_wput_opt &= ~(SW_SIGPIPE|SW_SNDZERO);
5450                 if (arg & SNDZERO)
5451                         stp->sd_wput_opt |= SW_SNDZERO;
5452                 if (arg & SNDPIPE)
5453                         stp->sd_wput_opt |= SW_SIGPIPE;
5454                 mutex_exit(&stp->sd_lock);
5455                 return (0);
5456 
5457         case I_GWROPT:
5458         {
5459                 int wropt = 0;
5460 
5461                 if (stp->sd_wput_opt & SW_SNDZERO)
5462                         wropt |= SNDZERO;
5463                 if (stp->sd_wput_opt & SW_SIGPIPE)
5464                         wropt |= SNDPIPE;
5465                 return (strcopyout(&wropt, (void *)arg, sizeof (wropt),
5466                     copyflag));
5467         }
5468 
5469         case I_LIST:
5470                 /*
5471                  * Returns all the modules found on this stream,
5472                  * upto the driver. If argument is NULL, return the
5473                  * number of modules (including driver). If argument
5474                  * is not NULL, copy the names into the structure
5475                  * provided.
5476                  */
5477 
5478         {
5479                 queue_t *q;
5480                 char *qname;
5481                 int i, nmods;
5482                 struct str_mlist *mlist;
5483                 STRUCT_DECL(str_list, strlist);
5484 
5485                 if (arg == NULL) { /* Return number of modules plus driver */
5486                         if (stp->sd_vnode->v_type == VFIFO)
5487                                 *rvalp = stp->sd_pushcnt;
5488                         else
5489                                 *rvalp = stp->sd_pushcnt + 1;
5490                         return (0);
5491                 }
5492 
5493                 STRUCT_INIT(strlist, flag);
5494 
5495                 error = strcopyin((void *)arg, STRUCT_BUF(strlist),
5496                     STRUCT_SIZE(strlist), copyflag);
5497                 if (error != 0)
5498                         return (error);
5499 
5500                 mlist = STRUCT_FGETP(strlist, sl_modlist);
5501                 nmods = STRUCT_FGET(strlist, sl_nmods);
5502                 if (nmods <= 0)
5503                         return (EINVAL);
5504 
5505                 claimstr(stp->sd_wrq);
5506                 q = stp->sd_wrq;
5507                 for (i = 0; i < nmods && _SAMESTR(q); i++, q = q->q_next) {
5508                         qname = Q2NAME(q->q_next);
5509                         error = strcopyout(qname, &mlist[i], strlen(qname) + 1,
5510                             copyflag);
5511                         if (error != 0) {
5512                                 releasestr(stp->sd_wrq);
5513                                 return (error);
5514                         }
5515                 }
5516                 releasestr(stp->sd_wrq);
5517                 return (strcopyout(&i, (void *)arg, sizeof (int), copyflag));
5518         }
5519 
5520         case I_CKBAND:
5521         {
5522                 queue_t *q;
5523                 qband_t *qbp;
5524 
5525                 if ((arg < 0) || (arg >= NBAND))
5526                         return (EINVAL);
5527                 q = _RD(stp->sd_wrq);
5528                 mutex_enter(QLOCK(q));
5529                 if (arg > (int)q->q_nband) {
5530                         *rvalp = 0;
5531                 } else {
5532                         if (arg == 0) {
5533                                 if (q->q_first)
5534                                         *rvalp = 1;
5535                                 else
5536                                         *rvalp = 0;
5537                         } else {
5538                                 qbp = q->q_bandp;
5539                                 while (--arg > 0)
5540                                         qbp = qbp->qb_next;
5541                                 if (qbp->qb_first)
5542                                         *rvalp = 1;
5543                                 else
5544                                         *rvalp = 0;
5545                         }
5546                 }
5547                 mutex_exit(QLOCK(q));
5548                 return (0);
5549         }
5550 
5551         case I_GETBAND:
5552         {
5553                 int intpri;
5554                 queue_t *q;
5555 
5556                 q = _RD(stp->sd_wrq);
5557                 mutex_enter(QLOCK(q));
5558                 mp = q->q_first;
5559                 if (!mp) {
5560                         mutex_exit(QLOCK(q));
5561                         return (ENODATA);
5562                 }
5563                 intpri = (int)mp->b_band;
5564                 error = strcopyout(&intpri, (void *)arg, sizeof (int),
5565                     copyflag);
5566                 mutex_exit(QLOCK(q));
5567                 return (error);
5568         }
5569 
5570         case I_ATMARK:
5571         {
5572                 queue_t *q;
5573 
5574                 if (arg & ~(ANYMARK|LASTMARK))
5575                         return (EINVAL);
5576                 q = _RD(stp->sd_wrq);
5577                 mutex_enter(&stp->sd_lock);
5578                 if ((stp->sd_flag & STRATMARK) && (arg == ANYMARK)) {
5579                         *rvalp = 1;
5580                 } else {
5581                         mutex_enter(QLOCK(q));
5582                         mp = q->q_first;
5583 
5584                         if (mp == NULL)
5585                                 *rvalp = 0;
5586                         else if ((arg == ANYMARK) && (mp->b_flag & MSGMARK))
5587                                 *rvalp = 1;
5588                         else if ((arg == LASTMARK) && (mp == stp->sd_mark))
5589                                 *rvalp = 1;
5590                         else
5591                                 *rvalp = 0;
5592                         mutex_exit(QLOCK(q));
5593                 }
5594                 mutex_exit(&stp->sd_lock);
5595                 return (0);
5596         }
5597 
5598         case I_CANPUT:
5599         {
5600                 char band;
5601 
5602                 if ((arg < 0) || (arg >= NBAND))
5603                         return (EINVAL);
5604                 band = (char)arg;
5605                 *rvalp = bcanputnext(stp->sd_wrq, band);
5606                 return (0);
5607         }
5608 
5609         case I_SETCLTIME:
5610         {
5611                 int closetime;
5612 
5613                 error = strcopyin((void *)arg, &closetime, sizeof (int),
5614                     copyflag);
5615                 if (error)
5616                         return (error);
5617                 if (closetime < 0)
5618                         return (EINVAL);
5619 
5620                 stp->sd_closetime = closetime;
5621                 return (0);
5622         }
5623 
5624         case I_GETCLTIME:
5625         {
5626                 int closetime;
5627 
5628                 closetime = stp->sd_closetime;
5629                 return (strcopyout(&closetime, (void *)arg, sizeof (int),
5630                     copyflag));
5631         }
5632 
5633         case TIOCGSID:
5634         {
5635                 pid_t sid;
5636 
5637                 mutex_enter(&stp->sd_lock);
5638                 if (stp->sd_sidp == NULL) {
5639                         mutex_exit(&stp->sd_lock);
5640                         return (ENOTTY);
5641                 }
5642                 sid = stp->sd_sidp->pid_id;
5643                 mutex_exit(&stp->sd_lock);
5644                 return (strcopyout(&sid, (void *)arg, sizeof (pid_t),
5645                     copyflag));
5646         }
5647 
5648         case TIOCSPGRP:
5649         {
5650                 pid_t pgrp;
5651                 proc_t *q;
5652                 pid_t   sid, fg_pgid, bg_pgid;
5653 
5654                 if (error = strcopyin((void *)arg, &pgrp, sizeof (pid_t),
5655                     copyflag))
5656                         return (error);
5657                 mutex_enter(&stp->sd_lock);
5658                 mutex_enter(&pidlock);
5659                 if (stp->sd_sidp != ttoproc(curthread)->p_sessp->s_sidp) {
5660                         mutex_exit(&pidlock);
5661                         mutex_exit(&stp->sd_lock);
5662                         return (ENOTTY);
5663                 }
5664                 if (pgrp == stp->sd_pgidp->pid_id) {
5665                         mutex_exit(&pidlock);
5666                         mutex_exit(&stp->sd_lock);
5667                         return (0);
5668                 }
5669                 if (pgrp <= 0 || pgrp >= maxpid) {
5670                         mutex_exit(&pidlock);
5671                         mutex_exit(&stp->sd_lock);
5672                         return (EINVAL);
5673                 }
5674                 if ((q = pgfind(pgrp)) == NULL ||
5675                     q->p_sessp != ttoproc(curthread)->p_sessp) {
5676                         mutex_exit(&pidlock);
5677                         mutex_exit(&stp->sd_lock);
5678                         return (EPERM);
5679                 }
5680                 sid = stp->sd_sidp->pid_id;
5681                 fg_pgid = q->p_pgrp;
5682                 bg_pgid = stp->sd_pgidp->pid_id;
5683                 CL_SET_PROCESS_GROUP(curthread, sid, bg_pgid, fg_pgid);
5684                 PID_RELE(stp->sd_pgidp);
5685                 ctty_clear_sighuped();
5686                 stp->sd_pgidp = q->p_pgidp;
5687                 PID_HOLD(stp->sd_pgidp);
5688                 mutex_exit(&pidlock);
5689                 mutex_exit(&stp->sd_lock);
5690                 return (0);
5691         }
5692 
5693         case TIOCGPGRP:
5694         {
5695                 pid_t pgrp;
5696 
5697                 mutex_enter(&stp->sd_lock);
5698                 if (stp->sd_sidp == NULL) {
5699                         mutex_exit(&stp->sd_lock);
5700                         return (ENOTTY);
5701                 }
5702                 pgrp = stp->sd_pgidp->pid_id;
5703                 mutex_exit(&stp->sd_lock);
5704                 return (strcopyout(&pgrp, (void *)arg, sizeof (pid_t),
5705                     copyflag));
5706         }
5707 
5708         case TIOCSCTTY:
5709         {
5710                 return (strctty(stp));
5711         }
5712 
5713         case TIOCNOTTY:
5714         {
5715                 /* freectty() always assumes curproc. */
5716                 if (freectty(B_FALSE) != 0)
5717                         return (0);
5718                 return (ENOTTY);
5719         }
5720 
5721         case FIONBIO:
5722         case FIOASYNC:
5723                 return (0);     /* handled by the upper layer */
5724         }
5725 }
5726 
5727 /*
5728  * Custom free routine used for M_PASSFP messages.
5729  */
5730 static void
5731 free_passfp(struct k_strrecvfd *srf)
5732 {
5733         (void) closef(srf->fp);
5734         kmem_free(srf, sizeof (struct k_strrecvfd) + sizeof (frtn_t));
5735 }
5736 
5737 /* ARGSUSED */
5738 int
5739 do_sendfp(struct stdata *stp, struct file *fp, struct cred *cr)
5740 {
5741         queue_t *qp, *nextqp;
5742         struct k_strrecvfd *srf;
5743         mblk_t *mp;
5744         frtn_t *frtnp;
5745         size_t bufsize;
5746         queue_t *mate = NULL;
5747         syncq_t *sq = NULL;
5748         int retval = 0;
5749 
5750         if (stp->sd_flag & STRHUP)
5751                 return (ENXIO);
5752 
5753         claimstr(stp->sd_wrq);
5754 
5755         /* Fastpath, we have a pipe, and we are already mated, use it. */
5756         if (STRMATED(stp)) {
5757                 qp = _RD(stp->sd_mate->sd_wrq);
5758                 claimstr(qp);
5759                 mate = qp;
5760         } else { /* Not already mated. */
5761 
5762                 /*
5763                  * Walk the stream to the end of this one.
5764                  * assumes that the claimstr() will prevent
5765                  * plumbing between the stream head and the
5766                  * driver from changing
5767                  */
5768                 qp = stp->sd_wrq;
5769 
5770                 /*
5771                  * Loop until we reach the end of this stream.
5772                  * On completion, qp points to the write queue
5773                  * at the end of the stream, or the read queue
5774                  * at the stream head if this is a fifo.
5775                  */
5776                 while (((qp = qp->q_next) != NULL) && _SAMESTR(qp))
5777                         ;
5778 
5779                 /*
5780                  * Just in case we get a q_next which is NULL, but
5781                  * not at the end of the stream.  This is actually
5782                  * broken, so we set an assert to catch it in
5783                  * debug, and set an error and return if not debug.
5784                  */
5785                 ASSERT(qp);
5786                 if (qp == NULL) {
5787                         releasestr(stp->sd_wrq);
5788                         return (EINVAL);
5789                 }
5790 
5791                 /*
5792                  * Enter the syncq for the driver, so (hopefully)
5793                  * the queue values will not change on us.
5794                  * XXXX - This will only prevent the race IFF only
5795                  *   the write side modifies the q_next member, and
5796                  *   the put procedure is protected by at least
5797                  *   MT_PERQ.
5798                  */
5799                 if ((sq = qp->q_syncq) != NULL)
5800                         entersq(sq, SQ_PUT);
5801 
5802                 /* Now get the q_next value from this qp. */
5803                 nextqp = qp->q_next;
5804 
5805                 /*
5806                  * If nextqp exists and the other stream is different
5807                  * from this one claim the stream, set the mate, and
5808                  * get the read queue at the stream head of the other
5809                  * stream.  Assumes that nextqp was at least valid when
5810                  * we got it.  Hopefully the entersq of the driver
5811                  * will prevent it from changing on us.
5812                  */
5813                 if ((nextqp != NULL) && (STREAM(nextqp) != stp)) {
5814                         ASSERT(qp->q_qinfo->qi_srvp);
5815                         ASSERT(_OTHERQ(qp)->q_qinfo->qi_srvp);
5816                         ASSERT(_OTHERQ(qp->q_next)->q_qinfo->qi_srvp);
5817                         claimstr(nextqp);
5818 
5819                         /* Make sure we still have a q_next */
5820                         if (nextqp != qp->q_next) {
5821                                 releasestr(stp->sd_wrq);
5822                                 releasestr(nextqp);
5823                                 return (EINVAL);
5824                         }
5825 
5826                         qp = _RD(STREAM(nextqp)->sd_wrq);
5827                         mate = qp;
5828                 }
5829                 /* If we entered the synq above, leave it. */
5830                 if (sq != NULL)
5831                         leavesq(sq, SQ_PUT);
5832         } /*  STRMATED(STP)  */
5833 
5834         /* XXX prevents substitution of the ops vector */
5835         if (qp->q_qinfo != &strdata && qp->q_qinfo != &fifo_strdata) {
5836                 retval = EINVAL;
5837                 goto out;
5838         }
5839 
5840         if (qp->q_flag & QFULL) {
5841                 retval = EAGAIN;
5842                 goto out;
5843         }
5844 
5845         /*
5846          * Since M_PASSFP messages include a file descriptor, we use
5847          * esballoc() and specify a custom free routine (free_passfp()) that
5848          * will close the descriptor as part of freeing the message.  For
5849          * convenience, we stash the frtn_t right after the data block.
5850          */
5851         bufsize = sizeof (struct k_strrecvfd) + sizeof (frtn_t);
5852         srf = kmem_alloc(bufsize, KM_NOSLEEP);
5853         if (srf == NULL) {
5854                 retval = EAGAIN;
5855                 goto out;
5856         }
5857 
5858         frtnp = (frtn_t *)(srf + 1);
5859         frtnp->free_arg = (caddr_t)srf;
5860         frtnp->free_func = free_passfp;
5861 
5862         mp = esballoc((uchar_t *)srf, bufsize, BPRI_MED, frtnp);
5863         if (mp == NULL) {
5864                 kmem_free(srf, bufsize);
5865                 retval = EAGAIN;
5866                 goto out;
5867         }
5868         mp->b_wptr += sizeof (struct k_strrecvfd);
5869         mp->b_datap->db_type = M_PASSFP;
5870 
5871         srf->fp = fp;
5872         srf->uid = crgetuid(curthread->t_cred);
5873         srf->gid = crgetgid(curthread->t_cred);
5874         mutex_enter(&fp->f_tlock);
5875         fp->f_count++;
5876         mutex_exit(&fp->f_tlock);
5877 
5878         put(qp, mp);
5879 out:
5880         releasestr(stp->sd_wrq);
5881         if (mate)
5882                 releasestr(mate);
5883         return (retval);
5884 }
5885 
5886 /*
5887  * Send an ioctl message downstream and wait for acknowledgement.
5888  * flags may be set to either U_TO_K or K_TO_K and a combination
5889  * of STR_NOERROR or STR_NOSIG
5890  * STR_NOSIG: Signals are essentially ignored or held and have
5891  *      no effect for the duration of the call.
5892  * STR_NOERROR: Ignores stream head read, write and hup errors.
5893  *      Additionally, if an existing ioctl times out, it is assumed
5894  *      lost and and this ioctl will continue as if the previous ioctl had
5895  *      finished.  ETIME may be returned if this ioctl times out (i.e.
5896  *      ic_timout is not INFTIM).  Non-stream head errors may be returned if
5897  *      the ioc_error indicates that the driver/module had problems,
5898  *      an EFAULT was found when accessing user data, a lack of
5899  *      resources, etc.
5900  */
5901 int
5902 strdoioctl(
5903         struct stdata *stp,
5904         struct strioctl *strioc,
5905         int fflags,             /* file flags with model info */
5906         int flag,
5907         cred_t *crp,
5908         int *rvalp)
5909 {
5910         mblk_t *bp;
5911         struct iocblk *iocbp;
5912         struct copyreq *reqp;
5913         struct copyresp *resp;
5914         int id;
5915         int transparent = 0;
5916         int error = 0;
5917         int len = 0;
5918         caddr_t taddr;
5919         int copyflag = (flag & (U_TO_K | K_TO_K));
5920         int sigflag = (flag & STR_NOSIG);
5921         int errs;
5922         uint_t waitflags;
5923         boolean_t set_iocwaitne = B_FALSE;
5924 
5925         ASSERT(copyflag == U_TO_K || copyflag == K_TO_K);
5926         ASSERT((fflags & FMODELS) != 0);
5927 
5928         TRACE_2(TR_FAC_STREAMS_FR,
5929             TR_STRDOIOCTL,
5930             "strdoioctl:stp %p strioc %p", stp, strioc);
5931         if (strioc->ic_len == TRANSPARENT) { /* send arg in M_DATA block */
5932                 transparent = 1;
5933                 strioc->ic_len = sizeof (intptr_t);
5934         }
5935 
5936         if (strioc->ic_len < 0 || (strmsgsz > 0 && strioc->ic_len > strmsgsz))
5937                 return (EINVAL);
5938 
5939         if ((bp = allocb_cred_wait(sizeof (union ioctypes), sigflag, &error,
5940             crp, curproc->p_pid)) == NULL)
5941                         return (error);
5942 
5943         bzero(bp->b_wptr, sizeof (union ioctypes));
5944 
5945         iocbp = (struct iocblk *)bp->b_wptr;
5946         iocbp->ioc_count = strioc->ic_len;
5947         iocbp->ioc_cmd = strioc->ic_cmd;
5948         iocbp->ioc_flag = (fflags & FMODELS);
5949 
5950         crhold(crp);
5951         iocbp->ioc_cr = crp;
5952         DB_TYPE(bp) = M_IOCTL;
5953         bp->b_wptr += sizeof (struct iocblk);
5954 
5955         if (flag & STR_NOERROR)
5956                 errs = STPLEX;
5957         else
5958                 errs = STRHUP|STRDERR|STWRERR|STPLEX;
5959 
5960         /*
5961          * If there is data to copy into ioctl block, do so.
5962          */
5963         if (iocbp->ioc_count > 0) {
5964                 if (transparent)
5965                         /*
5966                          * Note: STR_NOERROR does not have an effect
5967                          * in putiocd()
5968                          */
5969                         id = K_TO_K | sigflag;
5970                 else
5971                         id = flag;
5972                 if ((error = putiocd(bp, strioc->ic_dp, id, crp)) != 0) {
5973                         freemsg(bp);
5974                         crfree(crp);
5975                         return (error);
5976                 }
5977 
5978                 /*
5979                  * We could have slept copying in user pages.
5980                  * Recheck the stream head state (the other end
5981                  * of a pipe could have gone away).
5982                  */
5983                 if (stp->sd_flag & errs) {
5984                         mutex_enter(&stp->sd_lock);
5985                         error = strgeterr(stp, errs, 0);
5986                         mutex_exit(&stp->sd_lock);
5987                         if (error != 0) {
5988                                 freemsg(bp);
5989                                 crfree(crp);
5990                                 return (error);
5991                         }
5992                 }
5993         }
5994         if (transparent)
5995                 iocbp->ioc_count = TRANSPARENT;
5996 
5997         /*
5998          * Block for up to STRTIMOUT milliseconds if there is an outstanding
5999          * ioctl for this stream already running.  All processes
6000          * sleeping here will be awakened as a result of an ACK
6001          * or NAK being received for the outstanding ioctl, or
6002          * as a result of the timer expiring on the outstanding
6003          * ioctl (a failure), or as a result of any waiting
6004          * process's timer expiring (also a failure).
6005          */
6006 
6007         error = 0;
6008         mutex_enter(&stp->sd_lock);
6009         while ((stp->sd_flag & IOCWAIT) ||
6010             (!set_iocwaitne && (stp->sd_flag & IOCWAITNE))) {
6011                 clock_t cv_rval;
6012 
6013                 TRACE_0(TR_FAC_STREAMS_FR,
6014                     TR_STRDOIOCTL_WAIT,
6015                     "strdoioctl sleeps - IOCWAIT");
6016                 cv_rval = str_cv_wait(&stp->sd_iocmonitor, &stp->sd_lock,
6017                     STRTIMOUT, sigflag);
6018                 if (cv_rval <= 0) {
6019                         if (cv_rval == 0) {
6020                                 error = EINTR;
6021                         } else {
6022                                 if (flag & STR_NOERROR) {
6023                                         /*
6024                                          * Terminating current ioctl in
6025                                          * progress -- assume it got lost and
6026                                          * wake up the other thread so that the
6027                                          * operation completes.
6028                                          */
6029                                         if (!(stp->sd_flag & IOCWAITNE)) {
6030                                                 set_iocwaitne = B_TRUE;
6031                                                 stp->sd_flag |= IOCWAITNE;
6032                                                 cv_broadcast(&stp->sd_monitor);
6033                                         }
6034                                         /*
6035                                          * Otherwise, there's a running
6036                                          * STR_NOERROR -- we have no choice
6037                                          * here but to wait forever (or until
6038                                          * interrupted).
6039                                          */
6040                                 } else {
6041                                         /*
6042                                          * pending ioctl has caused
6043                                          * us to time out
6044                                          */
6045                                         error = ETIME;
6046                                 }
6047                         }
6048                 } else if ((stp->sd_flag & errs)) {
6049                         error = strgeterr(stp, errs, 0);
6050                 }
6051                 if (error) {
6052                         mutex_exit(&stp->sd_lock);
6053                         freemsg(bp);
6054                         crfree(crp);
6055                         return (error);
6056                 }
6057         }
6058 
6059         /*
6060          * Have control of ioctl mechanism.
6061          * Send down ioctl packet and wait for response.
6062          */
6063         if (stp->sd_iocblk != (mblk_t *)-1) {
6064                 freemsg(stp->sd_iocblk);
6065         }
6066         stp->sd_iocblk = NULL;
6067 
6068         /*
6069          * If this is marked with 'noerror' (internal; mostly
6070          * I_{P,}{UN,}LINK), then make sure nobody else is able to get
6071          * in here by setting IOCWAITNE.
6072          */
6073         waitflags = IOCWAIT;
6074         if (flag & STR_NOERROR)
6075                 waitflags |= IOCWAITNE;
6076 
6077         stp->sd_flag |= waitflags;
6078 
6079         /*
6080          * Assign sequence number.
6081          */
6082         iocbp->ioc_id = stp->sd_iocid = getiocseqno();
6083 
6084         mutex_exit(&stp->sd_lock);
6085 
6086         TRACE_1(TR_FAC_STREAMS_FR,
6087             TR_STRDOIOCTL_PUT, "strdoioctl put: stp %p", stp);
6088         stream_willservice(stp);
6089         putnext(stp->sd_wrq, bp);
6090         stream_runservice(stp);
6091 
6092         /*
6093          * Timed wait for acknowledgment.  The wait time is limited by the
6094          * timeout value, which must be a positive integer (number of
6095          * milliseconds) to wait, or 0 (use default value of STRTIMOUT
6096          * milliseconds), or -1 (wait forever).  This will be awakened
6097          * either by an ACK/NAK message arriving, the timer expiring, or
6098          * the timer expiring on another ioctl waiting for control of the
6099          * mechanism.
6100          */
6101 waitioc:
6102         mutex_enter(&stp->sd_lock);
6103 
6104 
6105         /*
6106          * If the reply has already arrived, don't sleep.  If awakened from
6107          * the sleep, fail only if the reply has not arrived by then.
6108          * Otherwise, process the reply.
6109          */
6110         while (!stp->sd_iocblk) {
6111                 clock_t cv_rval;
6112 
6113                 if (stp->sd_flag & errs) {
6114                         error = strgeterr(stp, errs, 0);
6115                         if (error != 0) {
6116                                 stp->sd_flag &= ~waitflags;
6117                                 cv_broadcast(&stp->sd_iocmonitor);
6118                                 mutex_exit(&stp->sd_lock);
6119                                 crfree(crp);
6120                                 return (error);
6121                         }
6122                 }
6123 
6124                 TRACE_0(TR_FAC_STREAMS_FR,
6125                     TR_STRDOIOCTL_WAIT2,
6126                     "strdoioctl sleeps awaiting reply");
6127                 ASSERT(error == 0);
6128 
6129                 cv_rval = str_cv_wait(&stp->sd_monitor, &stp->sd_lock,
6130                     (strioc->ic_timout ?
6131                     strioc->ic_timout * 1000 : STRTIMOUT), sigflag);
6132 
6133                 /*
6134                  * There are four possible cases here: interrupt, timeout,
6135                  * wakeup by IOCWAITNE (above), or wakeup by strrput_nondata (a
6136                  * valid M_IOCTL reply).
6137                  *
6138                  * If we've been awakened by a STR_NOERROR ioctl on some other
6139                  * thread, then sd_iocblk will still be NULL, and IOCWAITNE
6140                  * will be set.  Pretend as if we just timed out.  Note that
6141                  * this other thread waited at least STRTIMOUT before trying to
6142                  * awaken our thread, so this is indistinguishable (even for
6143                  * INFTIM) from the case where we failed with ETIME waiting on
6144                  * IOCWAIT in the prior loop.
6145                  */
6146                 if (cv_rval > 0 && !(flag & STR_NOERROR) &&
6147                     stp->sd_iocblk == NULL && (stp->sd_flag & IOCWAITNE)) {
6148                         cv_rval = -1;
6149                 }
6150 
6151                 /*
6152                  * note: STR_NOERROR does not protect
6153                  * us here.. use ic_timout < 0
6154                  */
6155                 if (cv_rval <= 0) {
6156                         if (cv_rval == 0) {
6157                                 error = EINTR;
6158                         } else {
6159                                 error =  ETIME;
6160                         }
6161                         /*
6162                          * A message could have come in after we were scheduled
6163                          * but before we were actually run.
6164                          */
6165                         bp = stp->sd_iocblk;
6166                         stp->sd_iocblk = NULL;
6167                         if (bp != NULL) {
6168                                 if ((bp->b_datap->db_type == M_COPYIN) ||
6169                                     (bp->b_datap->db_type == M_COPYOUT)) {
6170                                         mutex_exit(&stp->sd_lock);
6171                                         if (bp->b_cont) {
6172                                                 freemsg(bp->b_cont);
6173                                                 bp->b_cont = NULL;
6174                                         }
6175                                         bp->b_datap->db_type = M_IOCDATA;
6176                                         bp->b_wptr = bp->b_rptr +
6177                                             sizeof (struct copyresp);
6178                                         resp = (struct copyresp *)bp->b_rptr;
6179                                         resp->cp_rval =
6180                                             (caddr_t)1; /* failure */
6181                                         stream_willservice(stp);
6182                                         putnext(stp->sd_wrq, bp);
6183                                         stream_runservice(stp);
6184                                         mutex_enter(&stp->sd_lock);
6185                                 } else {
6186                                         freemsg(bp);
6187                                 }
6188                         }
6189                         stp->sd_flag &= ~waitflags;
6190                         cv_broadcast(&stp->sd_iocmonitor);
6191                         mutex_exit(&stp->sd_lock);
6192                         crfree(crp);
6193                         return (error);
6194                 }
6195         }
6196         bp = stp->sd_iocblk;
6197         /*
6198          * Note: it is strictly impossible to get here with sd_iocblk set to
6199          * -1.  This is because the initial loop above doesn't allow any new
6200          * ioctls into the fray until all others have passed this point.
6201          */
6202         ASSERT(bp != NULL && bp != (mblk_t *)-1);
6203         TRACE_1(TR_FAC_STREAMS_FR,
6204             TR_STRDOIOCTL_ACK, "strdoioctl got reply: bp %p", bp);
6205         if ((bp->b_datap->db_type == M_IOCACK) ||
6206             (bp->b_datap->db_type == M_IOCNAK)) {
6207                 /* for detection of duplicate ioctl replies */
6208                 stp->sd_iocblk = (mblk_t *)-1;
6209                 stp->sd_flag &= ~waitflags;
6210                 cv_broadcast(&stp->sd_iocmonitor);
6211                 mutex_exit(&stp->sd_lock);
6212         } else {
6213                 /*
6214                  * flags not cleared here because we're still doing
6215                  * copy in/out for ioctl.
6216                  */
6217                 stp->sd_iocblk = NULL;
6218                 mutex_exit(&stp->sd_lock);
6219         }
6220 
6221 
6222         /*
6223          * Have received acknowledgment.
6224          */
6225 
6226         switch (bp->b_datap->db_type) {
6227         case M_IOCACK:
6228                 /*
6229                  * Positive ack.
6230                  */
6231                 iocbp = (struct iocblk *)bp->b_rptr;
6232 
6233                 /*
6234                  * Set error if indicated.
6235                  */
6236                 if (iocbp->ioc_error) {
6237                         error = iocbp->ioc_error;
6238                         break;
6239                 }
6240 
6241                 /*
6242                  * Set return value.
6243                  */
6244                 *rvalp = iocbp->ioc_rval;
6245 
6246                 /*
6247                  * Data may have been returned in ACK message (ioc_count > 0).
6248                  * If so, copy it out to the user's buffer.
6249                  */
6250                 if (iocbp->ioc_count && !transparent) {
6251                         if (error = getiocd(bp, strioc->ic_dp, copyflag))
6252                                 break;
6253                 }
6254                 if (!transparent) {
6255                         if (len)        /* an M_COPYOUT was used with I_STR */
6256                                 strioc->ic_len = len;
6257                         else
6258                                 strioc->ic_len = (int)iocbp->ioc_count;
6259                 }
6260                 break;
6261 
6262         case M_IOCNAK:
6263                 /*
6264                  * Negative ack.
6265                  *
6266                  * The only thing to do is set error as specified
6267                  * in neg ack packet.
6268                  */
6269                 iocbp = (struct iocblk *)bp->b_rptr;
6270 
6271                 error = (iocbp->ioc_error ? iocbp->ioc_error : EINVAL);
6272                 break;
6273 
6274         case M_COPYIN:
6275                 /*
6276                  * Driver or module has requested user ioctl data.
6277                  */
6278                 reqp = (struct copyreq *)bp->b_rptr;
6279 
6280                 /*
6281                  * M_COPYIN should *never* have a message attached, though
6282                  * it's harmless if it does -- thus, panic on a DEBUG
6283                  * kernel and just free it on a non-DEBUG build.
6284                  */
6285                 ASSERT(bp->b_cont == NULL);
6286                 if (bp->b_cont != NULL) {
6287                         freemsg(bp->b_cont);
6288                         bp->b_cont = NULL;
6289                 }
6290 
6291                 error = putiocd(bp, reqp->cq_addr, flag, crp);
6292                 if (error && bp->b_cont) {
6293                         freemsg(bp->b_cont);
6294                         bp->b_cont = NULL;
6295                 }
6296 
6297                 bp->b_wptr = bp->b_rptr + sizeof (struct copyresp);
6298                 bp->b_datap->db_type = M_IOCDATA;
6299 
6300                 mblk_setcred(bp, crp, curproc->p_pid);
6301                 resp = (struct copyresp *)bp->b_rptr;
6302                 resp->cp_rval = (caddr_t)(uintptr_t)error;
6303                 resp->cp_flag = (fflags & FMODELS);
6304 
6305                 stream_willservice(stp);
6306                 putnext(stp->sd_wrq, bp);
6307                 stream_runservice(stp);
6308 
6309                 if (error) {
6310                         mutex_enter(&stp->sd_lock);
6311                         stp->sd_flag &= ~waitflags;
6312                         cv_broadcast(&stp->sd_iocmonitor);
6313                         mutex_exit(&stp->sd_lock);
6314                         crfree(crp);
6315                         return (error);
6316                 }
6317 
6318                 goto waitioc;
6319 
6320         case M_COPYOUT:
6321                 /*
6322                  * Driver or module has ioctl data for a user.
6323                  */
6324                 reqp = (struct copyreq *)bp->b_rptr;
6325                 ASSERT(bp->b_cont != NULL);
6326 
6327                 /*
6328                  * Always (transparent or non-transparent )
6329                  * use the address specified in the request
6330                  */
6331                 taddr = reqp->cq_addr;
6332                 if (!transparent)
6333                         len = (int)reqp->cq_size;
6334 
6335                 /* copyout data to the provided address */
6336                 error = getiocd(bp, taddr, copyflag);
6337 
6338                 freemsg(bp->b_cont);
6339                 bp->b_cont = NULL;
6340 
6341                 bp->b_wptr = bp->b_rptr + sizeof (struct copyresp);
6342                 bp->b_datap->db_type = M_IOCDATA;
6343 
6344                 mblk_setcred(bp, crp, curproc->p_pid);
6345                 resp = (struct copyresp *)bp->b_rptr;
6346                 resp->cp_rval = (caddr_t)(uintptr_t)error;
6347                 resp->cp_flag = (fflags & FMODELS);
6348 
6349                 stream_willservice(stp);
6350                 putnext(stp->sd_wrq, bp);
6351                 stream_runservice(stp);
6352 
6353                 if (error) {
6354                         mutex_enter(&stp->sd_lock);
6355                         stp->sd_flag &= ~waitflags;
6356                         cv_broadcast(&stp->sd_iocmonitor);
6357                         mutex_exit(&stp->sd_lock);
6358                         crfree(crp);
6359                         return (error);
6360                 }
6361                 goto waitioc;
6362 
6363         default:
6364                 ASSERT(0);
6365                 mutex_enter(&stp->sd_lock);
6366                 stp->sd_flag &= ~waitflags;
6367                 cv_broadcast(&stp->sd_iocmonitor);
6368                 mutex_exit(&stp->sd_lock);
6369                 break;
6370         }
6371 
6372         freemsg(bp);
6373         crfree(crp);
6374         return (error);
6375 }
6376 
6377 /*
6378  * Send an M_CMD message downstream and wait for a reply.  This is a ptools
6379  * special used to retrieve information from modules/drivers a stream without
6380  * being subjected to flow control or interfering with pending messages on the
6381  * stream (e.g. an ioctl in flight).
6382  */
6383 int
6384 strdocmd(struct stdata *stp, struct strcmd *scp, cred_t *crp)
6385 {
6386         mblk_t *mp;
6387         struct cmdblk *cmdp;
6388         int error = 0;
6389         int errs = STRHUP|STRDERR|STWRERR|STPLEX;
6390         clock_t rval, timeout = STRTIMOUT;
6391 
6392         if (scp->sc_len < 0 || scp->sc_len > sizeof (scp->sc_buf) ||
6393             scp->sc_timeout < -1)
6394                 return (EINVAL);
6395 
6396         if (scp->sc_timeout > 0)
6397                 timeout = scp->sc_timeout * MILLISEC;
6398 
6399         if ((mp = allocb_cred(sizeof (struct cmdblk), crp,
6400             curproc->p_pid)) == NULL)
6401                 return (ENOMEM);
6402 
6403         crhold(crp);
6404 
6405         cmdp = (struct cmdblk *)mp->b_wptr;
6406         cmdp->cb_cr = crp;
6407         cmdp->cb_cmd = scp->sc_cmd;
6408         cmdp->cb_len = scp->sc_len;
6409         cmdp->cb_error = 0;
6410         mp->b_wptr += sizeof (struct cmdblk);
6411 
6412         DB_TYPE(mp) = M_CMD;
6413         DB_CPID(mp) = curproc->p_pid;
6414 
6415         /*
6416          * Copy in the payload.
6417          */
6418         if (cmdp->cb_len > 0) {
6419                 mp->b_cont = allocb_cred(sizeof (scp->sc_buf), crp,
6420                     curproc->p_pid);
6421                 if (mp->b_cont == NULL) {
6422                         error = ENOMEM;
6423                         goto out;
6424                 }
6425 
6426                 /* cb_len comes from sc_len, which has already been checked */
6427                 ASSERT(cmdp->cb_len <= sizeof (scp->sc_buf));
6428                 (void) bcopy(scp->sc_buf, mp->b_cont->b_wptr, cmdp->cb_len);
6429                 mp->b_cont->b_wptr += cmdp->cb_len;
6430                 DB_CPID(mp->b_cont) = curproc->p_pid;
6431         }
6432 
6433         /*
6434          * Since this mechanism is strictly for ptools, and since only one
6435          * process can be grabbed at a time, we simply fail if there's
6436          * currently an operation pending.
6437          */
6438         mutex_enter(&stp->sd_lock);
6439         if (stp->sd_flag & STRCMDWAIT) {
6440                 mutex_exit(&stp->sd_lock);
6441                 error = EBUSY;
6442                 goto out;
6443         }
6444         stp->sd_flag |= STRCMDWAIT;
6445         ASSERT(stp->sd_cmdblk == NULL);
6446         mutex_exit(&stp->sd_lock);
6447 
6448         putnext(stp->sd_wrq, mp);
6449         mp = NULL;
6450 
6451         /*
6452          * Timed wait for acknowledgment.  If the reply has already arrived,
6453          * don't sleep.  If awakened from the sleep, fail only if the reply
6454          * has not arrived by then.  Otherwise, process the reply.
6455          */
6456         mutex_enter(&stp->sd_lock);
6457         while (stp->sd_cmdblk == NULL) {
6458                 if (stp->sd_flag & errs) {
6459                         if ((error = strgeterr(stp, errs, 0)) != 0)
6460                                 goto waitout;
6461                 }
6462 
6463                 rval = str_cv_wait(&stp->sd_monitor, &stp->sd_lock, timeout, 0);
6464                 if (stp->sd_cmdblk != NULL)
6465                         break;
6466 
6467                 if (rval <= 0) {
6468                         error = (rval == 0) ? EINTR : ETIME;
6469                         goto waitout;
6470                 }
6471         }
6472 
6473         /*
6474          * We received a reply.
6475          */
6476         mp = stp->sd_cmdblk;
6477         stp->sd_cmdblk = NULL;
6478         ASSERT(mp != NULL && DB_TYPE(mp) == M_CMD);
6479         ASSERT(stp->sd_flag & STRCMDWAIT);
6480         stp->sd_flag &= ~STRCMDWAIT;
6481         mutex_exit(&stp->sd_lock);
6482 
6483         cmdp = (struct cmdblk *)mp->b_rptr;
6484         if ((error = cmdp->cb_error) != 0)
6485                 goto out;
6486 
6487         /*
6488          * Data may have been returned in the reply (cb_len > 0).
6489          * If so, copy it out to the user's buffer.
6490          */
6491         if (cmdp->cb_len > 0) {
6492                 if (mp->b_cont == NULL || MBLKL(mp->b_cont) < cmdp->cb_len) {
6493                         error = EPROTO;
6494                         goto out;
6495                 }
6496 
6497                 cmdp->cb_len = MIN(cmdp->cb_len, sizeof (scp->sc_buf));
6498                 (void) bcopy(mp->b_cont->b_rptr, scp->sc_buf, cmdp->cb_len);
6499         }
6500         scp->sc_len = cmdp->cb_len;
6501 out:
6502         freemsg(mp);
6503         crfree(crp);
6504         return (error);
6505 waitout:
6506         ASSERT(stp->sd_cmdblk == NULL);
6507         stp->sd_flag &= ~STRCMDWAIT;
6508         mutex_exit(&stp->sd_lock);
6509         crfree(crp);
6510         return (error);
6511 }
6512 
6513 /*
6514  * For the SunOS keyboard driver.
6515  * Return the next available "ioctl" sequence number.
6516  * Exported, so that streams modules can send "ioctl" messages
6517  * downstream from their open routine.
6518  */
6519 int
6520 getiocseqno(void)
6521 {
6522         int     i;
6523 
6524         mutex_enter(&strresources);
6525         i = ++ioc_id;
6526         mutex_exit(&strresources);
6527         return (i);
6528 }
6529 
6530 /*
6531  * Get the next message from the read queue.  If the message is
6532  * priority, STRPRI will have been set by strrput().  This flag
6533  * should be reset only when the entire message at the front of the
6534  * queue as been consumed.
6535  *
6536  * NOTE: strgetmsg and kstrgetmsg have much of the logic in common.
6537  */
6538 int
6539 strgetmsg(
6540         struct vnode *vp,
6541         struct strbuf *mctl,
6542         struct strbuf *mdata,
6543         unsigned char *prip,
6544         int *flagsp,
6545         int fmode,
6546         rval_t *rvp)
6547 {
6548         struct stdata *stp;
6549         mblk_t *bp, *nbp;
6550         mblk_t *savemp = NULL;
6551         mblk_t *savemptail = NULL;
6552         uint_t old_sd_flag;
6553         int flg;
6554         int more = 0;
6555         int error = 0;
6556         char first = 1;
6557         uint_t mark;            /* Contains MSG*MARK and _LASTMARK */
6558 #define _LASTMARK       0x8000  /* Distinct from MSG*MARK */
6559         unsigned char pri = 0;
6560         queue_t *q;
6561         int     pr = 0;                 /* Partial read successful */
6562         struct uio uios;
6563         struct uio *uiop = &uios;
6564         struct iovec iovs;
6565         unsigned char type;
6566 
6567         TRACE_1(TR_FAC_STREAMS_FR, TR_STRGETMSG_ENTER,
6568             "strgetmsg:%p", vp);
6569 
6570         ASSERT(vp->v_stream);
6571         stp = vp->v_stream;
6572         rvp->r_val1 = 0;
6573 
6574         mutex_enter(&stp->sd_lock);
6575 
6576         if ((error = i_straccess(stp, JCREAD)) != 0) {
6577                 mutex_exit(&stp->sd_lock);
6578                 return (error);
6579         }
6580 
6581         if (stp->sd_flag & (STRDERR|STPLEX)) {
6582                 error = strgeterr(stp, STRDERR|STPLEX, 0);
6583                 if (error != 0) {
6584                         mutex_exit(&stp->sd_lock);
6585                         return (error);
6586                 }
6587         }
6588         mutex_exit(&stp->sd_lock);
6589 
6590         switch (*flagsp) {
6591         case MSG_HIPRI:
6592                 if (*prip != 0)
6593                         return (EINVAL);
6594                 break;
6595 
6596         case MSG_ANY:
6597         case MSG_BAND:
6598                 break;
6599 
6600         default:
6601                 return (EINVAL);
6602         }
6603         /*
6604          * Setup uio and iov for data part
6605          */
6606         iovs.iov_base = mdata->buf;
6607         iovs.iov_len = mdata->maxlen;
6608         uios.uio_iov = &iovs;
6609         uios.uio_iovcnt = 1;
6610         uios.uio_loffset = 0;
6611         uios.uio_segflg = UIO_USERSPACE;
6612         uios.uio_fmode = 0;
6613         uios.uio_extflg = UIO_COPY_CACHED;
6614         uios.uio_resid = mdata->maxlen;
6615         uios.uio_offset = 0;
6616 
6617         q = _RD(stp->sd_wrq);
6618         mutex_enter(&stp->sd_lock);
6619         old_sd_flag = stp->sd_flag;
6620         mark = 0;
6621         for (;;) {
6622                 int done = 0;
6623                 mblk_t *q_first = q->q_first;
6624 
6625                 /*
6626                  * Get the next message of appropriate priority
6627                  * from the stream head.  If the caller is interested
6628                  * in band or hipri messages, then they should already
6629                  * be enqueued at the stream head.  On the other hand
6630                  * if the caller wants normal (band 0) messages, they
6631                  * might be deferred in a synchronous stream and they
6632                  * will need to be pulled up.
6633                  *
6634                  * After we have dequeued a message, we might find that
6635                  * it was a deferred M_SIG that was enqueued at the
6636                  * stream head.  It must now be posted as part of the
6637                  * read by calling strsignal_nolock().
6638                  *
6639                  * Also note that strrput does not enqueue an M_PCSIG,
6640                  * and there cannot be more than one hipri message,
6641                  * so there was no need to have the M_PCSIG case.
6642                  *
6643                  * At some time it might be nice to try and wrap the
6644                  * functionality of kstrgetmsg() and strgetmsg() into
6645                  * a common routine so to reduce the amount of replicated
6646                  * code (since they are extremely similar).
6647                  */
6648                 if (!(*flagsp & (MSG_HIPRI|MSG_BAND))) {
6649                         /* Asking for normal, band0 data */
6650                         bp = strget(stp, q, uiop, first, &error);
6651                         ASSERT(MUTEX_HELD(&stp->sd_lock));
6652                         if (bp != NULL) {
6653                                 if (DB_TYPE(bp) == M_SIG) {
6654                                         strsignal_nolock(stp, *bp->b_rptr,
6655                                             bp->b_band);
6656                                         freemsg(bp);
6657                                         continue;
6658                                 } else {
6659                                         break;
6660                                 }
6661                         }
6662                         if (error != 0)
6663                                 goto getmout;
6664 
6665                 /*
6666                  * We can't depend on the value of STRPRI here because
6667                  * the stream head may be in transit. Therefore, we
6668                  * must look at the type of the first message to
6669                  * determine if a high priority messages is waiting
6670                  */
6671                 } else if ((*flagsp & MSG_HIPRI) && q_first != NULL &&
6672                     DB_TYPE(q_first) >= QPCTL &&
6673                     (bp = getq_noenab(q, 0)) != NULL) {
6674                         /* Asked for HIPRI and got one */
6675                         ASSERT(DB_TYPE(bp) >= QPCTL);
6676                         break;
6677                 } else if ((*flagsp & MSG_BAND) && q_first != NULL &&
6678                     ((q_first->b_band >= *prip) || DB_TYPE(q_first) >= QPCTL) &&
6679                     (bp = getq_noenab(q, 0)) != NULL) {
6680                         /*
6681                          * Asked for at least band "prip" and got either at
6682                          * least that band or a hipri message.
6683                          */
6684                         ASSERT(bp->b_band >= *prip || DB_TYPE(bp) >= QPCTL);
6685                         if (DB_TYPE(bp) == M_SIG) {
6686                                 strsignal_nolock(stp, *bp->b_rptr, bp->b_band);
6687                                 freemsg(bp);
6688                                 continue;
6689                         } else {
6690                                 break;
6691                         }
6692                 }
6693 
6694                 /* No data. Time to sleep? */
6695                 qbackenable(q, 0);
6696 
6697                 /*
6698                  * If STRHUP or STREOF, return 0 length control and data.
6699                  * If resid is 0, then a read(fd,buf,0) was done. Do not
6700                  * sleep to satisfy this request because by default we have
6701                  * zero bytes to return.
6702                  */
6703                 if ((stp->sd_flag & (STRHUP|STREOF)) || (mctl->maxlen == 0 &&
6704                     mdata->maxlen == 0)) {
6705                         mctl->len = mdata->len = 0;
6706                         *flagsp = 0;
6707                         mutex_exit(&stp->sd_lock);
6708                         return (0);
6709                 }
6710                 TRACE_2(TR_FAC_STREAMS_FR, TR_STRGETMSG_WAIT,
6711                     "strgetmsg calls strwaitq:%p, %p",
6712                     vp, uiop);
6713                 if (((error = strwaitq(stp, GETWAIT, (ssize_t)0, fmode, -1,
6714                     &done)) != 0) || done) {
6715                         TRACE_2(TR_FAC_STREAMS_FR, TR_STRGETMSG_DONE,
6716                             "strgetmsg error or done:%p, %p",
6717                             vp, uiop);
6718                         mutex_exit(&stp->sd_lock);
6719                         return (error);
6720                 }
6721                 TRACE_2(TR_FAC_STREAMS_FR, TR_STRGETMSG_AWAKE,
6722                     "strgetmsg awakes:%p, %p", vp, uiop);
6723                 if ((error = i_straccess(stp, JCREAD)) != 0) {
6724                         mutex_exit(&stp->sd_lock);
6725                         return (error);
6726                 }
6727                 first = 0;
6728         }
6729         ASSERT(bp != NULL);
6730         /*
6731          * Extract any mark information. If the message is not completely
6732          * consumed this information will be put in the mblk
6733          * that is putback.
6734          * If MSGMARKNEXT is set and the message is completely consumed
6735          * the STRATMARK flag will be set below. Likewise, if
6736          * MSGNOTMARKNEXT is set and the message is
6737          * completely consumed STRNOTATMARK will be set.
6738          */
6739         mark = bp->b_flag & (MSGMARK | MSGMARKNEXT | MSGNOTMARKNEXT);
6740         ASSERT((mark & (MSGMARKNEXT|MSGNOTMARKNEXT)) !=
6741             (MSGMARKNEXT|MSGNOTMARKNEXT));
6742         if (mark != 0 && bp == stp->sd_mark) {
6743                 mark |= _LASTMARK;
6744                 stp->sd_mark = NULL;
6745         }
6746         /*
6747          * keep track of the original message type and priority
6748          */
6749         pri = bp->b_band;
6750         type = bp->b_datap->db_type;
6751         if (type == M_PASSFP) {
6752                 if ((mark & _LASTMARK) && (stp->sd_mark == NULL))
6753                         stp->sd_mark = bp;
6754                 bp->b_flag |= mark & ~_LASTMARK;
6755                 putback(stp, q, bp, pri);
6756                 qbackenable(q, pri);
6757                 mutex_exit(&stp->sd_lock);
6758                 return (EBADMSG);
6759         }
6760         ASSERT(type != M_SIG);
6761 
6762         /*
6763          * Set this flag so strrput will not generate signals. Need to
6764          * make sure this flag is cleared before leaving this routine
6765          * else signals will stop being sent.
6766          */
6767         stp->sd_flag |= STRGETINPROG;
6768         mutex_exit(&stp->sd_lock);
6769 
6770         if (STREAM_NEEDSERVICE(stp))
6771                 stream_runservice(stp);
6772 
6773         /*
6774          * Set HIPRI flag if message is priority.
6775          */
6776         if (type >= QPCTL)
6777                 flg = MSG_HIPRI;
6778         else
6779                 flg = MSG_BAND;
6780 
6781         /*
6782          * First process PROTO or PCPROTO blocks, if any.
6783          */
6784         if (mctl->maxlen >= 0 && type != M_DATA) {
6785                 size_t  n, bcnt;
6786                 char    *ubuf;
6787 
6788                 bcnt = mctl->maxlen;
6789                 ubuf = mctl->buf;
6790                 while (bp != NULL && bp->b_datap->db_type != M_DATA) {
6791                         if ((n = MIN(bcnt, bp->b_wptr - bp->b_rptr)) != 0 &&
6792                             copyout(bp->b_rptr, ubuf, n)) {
6793                                 error = EFAULT;
6794                                 mutex_enter(&stp->sd_lock);
6795                                 /*
6796                                  * clear stream head pri flag based on
6797                                  * first message type
6798                                  */
6799                                 if (type >= QPCTL) {
6800                                         ASSERT(type == M_PCPROTO);
6801                                         stp->sd_flag &= ~STRPRI;
6802                                 }
6803                                 more = 0;
6804                                 freemsg(bp);
6805                                 goto getmout;
6806                         }
6807                         ubuf += n;
6808                         bp->b_rptr += n;
6809                         if (bp->b_rptr >= bp->b_wptr) {
6810                                 nbp = bp;
6811                                 bp = bp->b_cont;
6812                                 freeb(nbp);
6813                         }
6814                         ASSERT(n <= bcnt);
6815                         bcnt -= n;
6816                         if (bcnt == 0)
6817                                 break;
6818                 }
6819                 mctl->len = mctl->maxlen - bcnt;
6820         } else
6821                 mctl->len = -1;
6822 
6823         if (bp && bp->b_datap->db_type != M_DATA) {
6824                 /*
6825                  * More PROTO blocks in msg.
6826                  */
6827                 more |= MORECTL;
6828                 savemp = bp;
6829                 while (bp && bp->b_datap->db_type != M_DATA) {
6830                         savemptail = bp;
6831                         bp = bp->b_cont;
6832                 }
6833                 savemptail->b_cont = NULL;
6834         }
6835 
6836         /*
6837          * Now process DATA blocks, if any.
6838          */
6839         if (mdata->maxlen >= 0 && bp) {
6840                 /*
6841                  * struiocopyout will consume a potential zero-length
6842                  * M_DATA even if uio_resid is zero.
6843                  */
6844                 size_t oldresid = uiop->uio_resid;
6845 
6846                 bp = struiocopyout(bp, uiop, &error);
6847                 if (error != 0) {
6848                         mutex_enter(&stp->sd_lock);
6849                         /*
6850                          * clear stream head hi pri flag based on
6851                          * first message
6852                          */
6853                         if (type >= QPCTL) {
6854                                 ASSERT(type == M_PCPROTO);
6855                                 stp->sd_flag &= ~STRPRI;
6856                         }
6857                         more = 0;
6858                         freemsg(savemp);
6859                         goto getmout;
6860                 }
6861                 /*
6862                  * (pr == 1) indicates a partial read.
6863                  */
6864                 if (oldresid > uiop->uio_resid)
6865                         pr = 1;
6866                 mdata->len = mdata->maxlen - uiop->uio_resid;
6867         } else
6868                 mdata->len = -1;
6869 
6870         if (bp) {                       /* more data blocks in msg */
6871                 more |= MOREDATA;
6872                 if (savemp)
6873                         savemptail->b_cont = bp;
6874                 else
6875                         savemp = bp;
6876         }
6877 
6878         mutex_enter(&stp->sd_lock);
6879         if (savemp) {
6880                 if (pr && (savemp->b_datap->db_type == M_DATA) &&
6881                     msgnodata(savemp)) {
6882                         /*
6883                          * Avoid queuing a zero-length tail part of
6884                          * a message. pr=1 indicates that we read some of
6885                          * the message.
6886                          */
6887                         freemsg(savemp);
6888                         more &= ~MOREDATA;
6889                         /*
6890                          * clear stream head hi pri flag based on
6891                          * first message
6892                          */
6893                         if (type >= QPCTL) {
6894                                 ASSERT(type == M_PCPROTO);
6895                                 stp->sd_flag &= ~STRPRI;
6896                         }
6897                 } else {
6898                         savemp->b_band = pri;
6899                         /*
6900                          * If the first message was HIPRI and the one we're
6901                          * putting back isn't, then clear STRPRI, otherwise
6902                          * set STRPRI again.  Note that we must set STRPRI
6903                          * again since the flush logic in strrput_nondata()
6904                          * may have cleared it while we had sd_lock dropped.
6905                          */
6906                         if (type >= QPCTL) {
6907                                 ASSERT(type == M_PCPROTO);
6908                                 if (queclass(savemp) < QPCTL)
6909                                         stp->sd_flag &= ~STRPRI;
6910                                 else
6911                                         stp->sd_flag |= STRPRI;
6912                         } else if (queclass(savemp) >= QPCTL) {
6913                                 /*
6914                                  * The first message was not a HIPRI message,
6915                                  * but the one we are about to putback is.
6916                                  * For simplicitly, we do not allow for HIPRI
6917                                  * messages to be embedded in the message
6918                                  * body, so just force it to same type as
6919                                  * first message.
6920                                  */
6921                                 ASSERT(type == M_DATA || type == M_PROTO);
6922                                 ASSERT(savemp->b_datap->db_type == M_PCPROTO);
6923                                 savemp->b_datap->db_type = type;
6924                         }
6925                         if (mark != 0) {
6926                                 savemp->b_flag |= mark & ~_LASTMARK;
6927                                 if ((mark & _LASTMARK) &&
6928                                     (stp->sd_mark == NULL)) {
6929                                         /*
6930                                          * If another marked message arrived
6931                                          * while sd_lock was not held sd_mark
6932                                          * would be non-NULL.
6933                                          */
6934                                         stp->sd_mark = savemp;
6935                                 }
6936                         }
6937                         putback(stp, q, savemp, pri);
6938                 }
6939         } else {
6940                 /*
6941                  * The complete message was consumed.
6942                  *
6943                  * If another M_PCPROTO arrived while sd_lock was not held
6944                  * it would have been discarded since STRPRI was still set.
6945                  *
6946                  * Move the MSG*MARKNEXT information
6947                  * to the stream head just in case
6948                  * the read queue becomes empty.
6949                  * clear stream head hi pri flag based on
6950                  * first message
6951                  *
6952                  * If the stream head was at the mark
6953                  * (STRATMARK) before we dropped sd_lock above
6954                  * and some data was consumed then we have
6955                  * moved past the mark thus STRATMARK is
6956                  * cleared. However, if a message arrived in
6957                  * strrput during the copyout above causing
6958                  * STRATMARK to be set we can not clear that
6959                  * flag.
6960                  */
6961                 if (type >= QPCTL) {
6962                         ASSERT(type == M_PCPROTO);
6963                         stp->sd_flag &= ~STRPRI;
6964                 }
6965                 if (mark & (MSGMARKNEXT|MSGNOTMARKNEXT|MSGMARK)) {
6966                         if (mark & MSGMARKNEXT) {
6967                                 stp->sd_flag &= ~STRNOTATMARK;
6968                                 stp->sd_flag |= STRATMARK;
6969                         } else if (mark & MSGNOTMARKNEXT) {
6970                                 stp->sd_flag &= ~STRATMARK;
6971                                 stp->sd_flag |= STRNOTATMARK;
6972                         } else {
6973                                 stp->sd_flag &= ~(STRATMARK|STRNOTATMARK);
6974                         }
6975                 } else if (pr && (old_sd_flag & STRATMARK)) {
6976                         stp->sd_flag &= ~STRATMARK;
6977                 }
6978         }
6979 
6980         *flagsp = flg;
6981         *prip = pri;
6982 
6983         /*
6984          * Getmsg cleanup processing - if the state of the queue has changed
6985          * some signals may need to be sent and/or poll awakened.
6986          */
6987 getmout:
6988         qbackenable(q, pri);
6989 
6990         /*
6991          * We dropped the stream head lock above. Send all M_SIG messages
6992          * before processing stream head for SIGPOLL messages.
6993          */
6994         ASSERT(MUTEX_HELD(&stp->sd_lock));
6995         while ((bp = q->q_first) != NULL &&
6996             (bp->b_datap->db_type == M_SIG)) {
6997                 /*
6998                  * sd_lock is held so the content of the read queue can not
6999                  * change.
7000                  */
7001                 bp = getq(q);
7002                 ASSERT(bp != NULL && bp->b_datap->db_type == M_SIG);
7003 
7004                 strsignal_nolock(stp, *bp->b_rptr, bp->b_band);
7005                 mutex_exit(&stp->sd_lock);
7006                 freemsg(bp);
7007                 if (STREAM_NEEDSERVICE(stp))
7008                         stream_runservice(stp);
7009                 mutex_enter(&stp->sd_lock);
7010         }
7011 
7012         /*
7013          * stream head cannot change while we make the determination
7014          * whether or not to send a signal. Drop the flag to allow strrput
7015          * to send firstmsgsigs again.
7016          */
7017         stp->sd_flag &= ~STRGETINPROG;
7018 
7019         /*
7020          * If the type of message at the front of the queue changed
7021          * due to the receive the appropriate signals and pollwakeup events
7022          * are generated. The type of changes are:
7023          *      Processed a hipri message, q_first is not hipri.
7024          *      Processed a band X message, and q_first is band Y.
7025          * The generated signals and pollwakeups are identical to what
7026          * strrput() generates should the message that is now on q_first
7027          * arrive to an empty read queue.
7028          *
7029          * Note: only strrput will send a signal for a hipri message.
7030          */
7031         if ((bp = q->q_first) != NULL && !(stp->sd_flag & STRPRI)) {
7032                 strsigset_t signals = 0;
7033                 strpollset_t pollwakeups = 0;
7034 
7035                 if (flg & MSG_HIPRI) {
7036                         /*
7037                          * Removed a hipri message. Regular data at
7038                          * the front of  the queue.
7039                          */
7040                         if (bp->b_band == 0) {
7041                                 signals = S_INPUT | S_RDNORM;
7042                                 pollwakeups = POLLIN | POLLRDNORM;
7043                         } else {
7044                                 signals = S_INPUT | S_RDBAND;
7045                                 pollwakeups = POLLIN | POLLRDBAND;
7046                         }
7047                 } else if (pri != bp->b_band) {
7048                         /*
7049                          * The band is different for the new q_first.
7050                          */
7051                         if (bp->b_band == 0) {
7052                                 signals = S_RDNORM;
7053                                 pollwakeups = POLLIN | POLLRDNORM;
7054                         } else {
7055                                 signals = S_RDBAND;
7056                                 pollwakeups = POLLIN | POLLRDBAND;
7057                         }
7058                 }
7059 
7060                 if (pollwakeups != 0) {
7061                         if (pollwakeups == (POLLIN | POLLRDNORM)) {
7062                                 if (!(stp->sd_rput_opt & SR_POLLIN))
7063                                         goto no_pollwake;
7064                                 stp->sd_rput_opt &= ~SR_POLLIN;
7065                         }
7066                         mutex_exit(&stp->sd_lock);
7067                         pollwakeup(&stp->sd_pollist, pollwakeups);
7068                         mutex_enter(&stp->sd_lock);
7069                 }
7070 no_pollwake:
7071 
7072                 if (stp->sd_sigflags & signals)
7073                         strsendsig(stp->sd_siglist, signals, bp->b_band, 0);
7074         }
7075         mutex_exit(&stp->sd_lock);
7076 
7077         rvp->r_val1 = more;
7078         return (error);
7079 #undef  _LASTMARK
7080 }
7081 
7082 /*
7083  * Get the next message from the read queue.  If the message is
7084  * priority, STRPRI will have been set by strrput().  This flag
7085  * should be reset only when the entire message at the front of the
7086  * queue as been consumed.
7087  *
7088  * If uiop is NULL all data is returned in mctlp.
7089  * Note that a NULL uiop implies that FNDELAY and FNONBLOCK are assumed
7090  * not enabled.
7091  * The timeout parameter is in milliseconds; -1 for infinity.
7092  * This routine handles the consolidation private flags:
7093  *      MSG_IGNERROR    Ignore any stream head error except STPLEX.
7094  *      MSG_DELAYERROR  Defer the error check until the queue is empty.
7095  *      MSG_HOLDSIG     Hold signals while waiting for data.
7096  *      MSG_IPEEK       Only peek at messages.
7097  *      MSG_DISCARDTAIL Discard the tail M_DATA part of the message
7098  *                      that doesn't fit.
7099  *      MSG_NOMARK      If the message is marked leave it on the queue.
7100  *
7101  * NOTE: strgetmsg and kstrgetmsg have much of the logic in common.
7102  */
7103 int
7104 kstrgetmsg(
7105         struct vnode *vp,
7106         mblk_t **mctlp,
7107         struct uio *uiop,
7108         unsigned char *prip,
7109         int *flagsp,
7110         clock_t timout,
7111         rval_t *rvp)
7112 {
7113         struct stdata *stp;
7114         mblk_t *bp, *nbp;
7115         mblk_t *savemp = NULL;
7116         mblk_t *savemptail = NULL;
7117         int flags;
7118         uint_t old_sd_flag;
7119         int flg;
7120         int more = 0;
7121         int error = 0;
7122         char first = 1;
7123         uint_t mark;            /* Contains MSG*MARK and _LASTMARK */
7124 #define _LASTMARK       0x8000  /* Distinct from MSG*MARK */
7125         unsigned char pri = 0;
7126         queue_t *q;
7127         int     pr = 0;                 /* Partial read successful */
7128         unsigned char type;
7129 
7130         TRACE_1(TR_FAC_STREAMS_FR, TR_KSTRGETMSG_ENTER,
7131             "kstrgetmsg:%p", vp);
7132 
7133         ASSERT(vp->v_stream);
7134         stp = vp->v_stream;
7135         rvp->r_val1 = 0;
7136 
7137         mutex_enter(&stp->sd_lock);
7138 
7139         if ((error = i_straccess(stp, JCREAD)) != 0) {
7140                 mutex_exit(&stp->sd_lock);
7141                 return (error);
7142         }
7143 
7144         flags = *flagsp;
7145         if (stp->sd_flag & (STRDERR|STPLEX)) {
7146                 if ((stp->sd_flag & STPLEX) ||
7147                     (flags & (MSG_IGNERROR|MSG_DELAYERROR)) == 0) {
7148                         error = strgeterr(stp, STRDERR|STPLEX,
7149                             (flags & MSG_IPEEK));
7150                         if (error != 0) {
7151                                 mutex_exit(&stp->sd_lock);
7152                                 return (error);
7153                         }
7154                 }
7155         }
7156         mutex_exit(&stp->sd_lock);
7157 
7158         switch (flags & (MSG_HIPRI|MSG_ANY|MSG_BAND)) {
7159         case MSG_HIPRI:
7160                 if (*prip != 0)
7161                         return (EINVAL);
7162                 break;
7163 
7164         case MSG_ANY:
7165         case MSG_BAND:
7166                 break;
7167 
7168         default:
7169                 return (EINVAL);
7170         }
7171 
7172 retry:
7173         q = _RD(stp->sd_wrq);
7174         mutex_enter(&stp->sd_lock);
7175         old_sd_flag = stp->sd_flag;
7176         mark = 0;
7177         for (;;) {
7178                 int done = 0;
7179                 int waitflag;
7180                 int fmode;
7181                 mblk_t *q_first = q->q_first;
7182 
7183                 /*
7184                  * This section of the code operates just like the code
7185                  * in strgetmsg().  There is a comment there about what
7186                  * is going on here.
7187                  */
7188                 if (!(flags & (MSG_HIPRI|MSG_BAND))) {
7189                         /* Asking for normal, band0 data */
7190                         bp = strget(stp, q, uiop, first, &error);
7191                         ASSERT(MUTEX_HELD(&stp->sd_lock));
7192                         if (bp != NULL) {
7193                                 if (DB_TYPE(bp) == M_SIG) {
7194                                         strsignal_nolock(stp, *bp->b_rptr,
7195                                             bp->b_band);
7196                                         freemsg(bp);
7197                                         continue;
7198                                 } else {
7199                                         break;
7200                                 }
7201                         }
7202                         if (error != 0) {
7203                                 goto getmout;
7204                         }
7205                 /*
7206                  * We can't depend on the value of STRPRI here because
7207                  * the stream head may be in transit. Therefore, we
7208                  * must look at the type of the first message to
7209                  * determine if a high priority messages is waiting
7210                  */
7211                 } else if ((flags & MSG_HIPRI) && q_first != NULL &&
7212                     DB_TYPE(q_first) >= QPCTL &&
7213                     (bp = getq_noenab(q, 0)) != NULL) {
7214                         ASSERT(DB_TYPE(bp) >= QPCTL);
7215                         break;
7216                 } else if ((flags & MSG_BAND) && q_first != NULL &&
7217                     ((q_first->b_band >= *prip) || DB_TYPE(q_first) >= QPCTL) &&
7218                     (bp = getq_noenab(q, 0)) != NULL) {
7219                         /*
7220                          * Asked for at least band "prip" and got either at
7221                          * least that band or a hipri message.
7222                          */
7223                         ASSERT(bp->b_band >= *prip || DB_TYPE(bp) >= QPCTL);
7224                         if (DB_TYPE(bp) == M_SIG) {
7225                                 strsignal_nolock(stp, *bp->b_rptr, bp->b_band);
7226                                 freemsg(bp);
7227                                 continue;
7228                         } else {
7229                                 break;
7230                         }
7231                 }
7232 
7233                 /* No data. Time to sleep? */
7234                 qbackenable(q, 0);
7235 
7236                 /*
7237                  * Delayed error notification?
7238                  */
7239                 if ((stp->sd_flag & (STRDERR|STPLEX)) &&
7240                     (flags & (MSG_IGNERROR|MSG_DELAYERROR)) == MSG_DELAYERROR) {
7241                         error = strgeterr(stp, STRDERR|STPLEX,
7242                             (flags & MSG_IPEEK));
7243                         if (error != 0) {
7244                                 mutex_exit(&stp->sd_lock);
7245                                 return (error);
7246                         }
7247                 }
7248 
7249                 /*
7250                  * If STRHUP or STREOF, return 0 length control and data.
7251                  * If a read(fd,buf,0) has been done, do not sleep, just
7252                  * return.
7253                  *
7254                  * If mctlp == NULL and uiop == NULL, then the code will
7255                  * do the strwaitq. This is an understood way of saying
7256                  * sleep "polling" until a message is received.
7257                  */
7258                 if ((stp->sd_flag & (STRHUP|STREOF)) ||
7259                     (uiop != NULL && uiop->uio_resid == 0)) {
7260                         if (mctlp != NULL)
7261                                 *mctlp = NULL;
7262                         *flagsp = 0;
7263                         mutex_exit(&stp->sd_lock);
7264                         return (0);
7265                 }
7266 
7267                 waitflag = GETWAIT;
7268                 if (flags &
7269                     (MSG_HOLDSIG|MSG_IGNERROR|MSG_IPEEK|MSG_DELAYERROR)) {
7270                         if (flags & MSG_HOLDSIG)
7271                                 waitflag |= STR_NOSIG;
7272                         if (flags & MSG_IGNERROR)
7273                                 waitflag |= STR_NOERROR;
7274                         if (flags & MSG_IPEEK)
7275                                 waitflag |= STR_PEEK;
7276                         if (flags & MSG_DELAYERROR)
7277                                 waitflag |= STR_DELAYERR;
7278                 }
7279                 if (uiop != NULL)
7280                         fmode = uiop->uio_fmode;
7281                 else
7282                         fmode = 0;
7283 
7284                 TRACE_2(TR_FAC_STREAMS_FR, TR_KSTRGETMSG_WAIT,
7285                     "kstrgetmsg calls strwaitq:%p, %p",
7286                     vp, uiop);
7287                 if (((error = strwaitq(stp, waitflag, (ssize_t)0,
7288                     fmode, timout, &done))) != 0 || done) {
7289                         TRACE_2(TR_FAC_STREAMS_FR, TR_KSTRGETMSG_DONE,
7290                             "kstrgetmsg error or done:%p, %p",
7291                             vp, uiop);
7292                         mutex_exit(&stp->sd_lock);
7293                         return (error);
7294                 }
7295                 TRACE_2(TR_FAC_STREAMS_FR, TR_KSTRGETMSG_AWAKE,
7296                     "kstrgetmsg awakes:%p, %p", vp, uiop);
7297                 if ((error = i_straccess(stp, JCREAD)) != 0) {
7298                         mutex_exit(&stp->sd_lock);
7299                         return (error);
7300                 }
7301                 first = 0;
7302         }
7303         ASSERT(bp != NULL);
7304         /*
7305          * Extract any mark information. If the message is not completely
7306          * consumed this information will be put in the mblk
7307          * that is putback.
7308          * If MSGMARKNEXT is set and the message is completely consumed
7309          * the STRATMARK flag will be set below. Likewise, if
7310          * MSGNOTMARKNEXT is set and the message is
7311          * completely consumed STRNOTATMARK will be set.
7312          */
7313         mark = bp->b_flag & (MSGMARK | MSGMARKNEXT | MSGNOTMARKNEXT);
7314         ASSERT((mark & (MSGMARKNEXT|MSGNOTMARKNEXT)) !=
7315             (MSGMARKNEXT|MSGNOTMARKNEXT));
7316         pri = bp->b_band;
7317         if (mark != 0) {
7318                 /*
7319                  * If the caller doesn't want the mark return.
7320                  * Used to implement MSG_WAITALL in sockets.
7321                  */
7322                 if (flags & MSG_NOMARK) {
7323                         putback(stp, q, bp, pri);
7324                         qbackenable(q, pri);
7325                         mutex_exit(&stp->sd_lock);
7326                         return (EWOULDBLOCK);
7327                 }
7328                 if (bp == stp->sd_mark) {
7329                         mark |= _LASTMARK;
7330                         stp->sd_mark = NULL;
7331                 }
7332         }
7333 
7334         /*
7335          * keep track of the first message type
7336          */
7337         type = bp->b_datap->db_type;
7338 
7339         if (bp->b_datap->db_type == M_PASSFP) {
7340                 if ((mark & _LASTMARK) && (stp->sd_mark == NULL))
7341                         stp->sd_mark = bp;
7342                 bp->b_flag |= mark & ~_LASTMARK;
7343                 putback(stp, q, bp, pri);
7344                 qbackenable(q, pri);
7345                 mutex_exit(&stp->sd_lock);
7346                 return (EBADMSG);
7347         }
7348         ASSERT(type != M_SIG);
7349 
7350         if (flags & MSG_IPEEK) {
7351                 /*
7352                  * Clear any struioflag - we do the uiomove over again
7353                  * when peeking since it simplifies the code.
7354                  *
7355                  * Dup the message and put the original back on the queue.
7356                  * If dupmsg() fails, try again with copymsg() to see if
7357                  * there is indeed a shortage of memory.  dupmsg() may fail
7358                  * if db_ref in any of the messages reaches its limit.
7359                  */
7360 
7361                 if ((nbp = dupmsg(bp)) == NULL && (nbp = copymsg(bp)) == NULL) {
7362                         /*
7363                          * Restore the state of the stream head since we
7364                          * need to drop sd_lock (strwaitbuf is sleeping).
7365                          */
7366                         size_t size = msgdsize(bp);
7367 
7368                         if ((mark & _LASTMARK) && (stp->sd_mark == NULL))
7369                                 stp->sd_mark = bp;
7370                         bp->b_flag |= mark & ~_LASTMARK;
7371                         putback(stp, q, bp, pri);
7372                         mutex_exit(&stp->sd_lock);
7373                         error = strwaitbuf(size, BPRI_HI);
7374                         if (error) {
7375                                 /*
7376                                  * There is no net change to the queue thus
7377                                  * no need to qbackenable.
7378                                  */
7379                                 return (error);
7380                         }
7381                         goto retry;
7382                 }
7383 
7384                 if ((mark & _LASTMARK) && (stp->sd_mark == NULL))
7385                         stp->sd_mark = bp;
7386                 bp->b_flag |= mark & ~_LASTMARK;
7387                 putback(stp, q, bp, pri);
7388                 bp = nbp;
7389         }
7390 
7391         /*
7392          * Set this flag so strrput will not generate signals. Need to
7393          * make sure this flag is cleared before leaving this routine
7394          * else signals will stop being sent.
7395          */
7396         stp->sd_flag |= STRGETINPROG;
7397         mutex_exit(&stp->sd_lock);
7398 
7399         if ((stp->sd_rputdatafunc != NULL) && (DB_TYPE(bp) == M_DATA)) {
7400                 mblk_t *tmp, *prevmp;
7401 
7402                 /*
7403                  * Put first non-data mblk back to stream head and
7404                  * cut the mblk chain so sd_rputdatafunc only sees
7405                  * M_DATA mblks. We can skip the first mblk since it
7406                  * is M_DATA according to the condition above.
7407                  */
7408                 for (prevmp = bp, tmp = bp->b_cont; tmp != NULL;
7409                     prevmp = tmp, tmp = tmp->b_cont) {
7410                         if (DB_TYPE(tmp) != M_DATA) {
7411                                 prevmp->b_cont = NULL;
7412                                 mutex_enter(&stp->sd_lock);
7413                                 putback(stp, q, tmp, tmp->b_band);
7414                                 mutex_exit(&stp->sd_lock);
7415                                 break;
7416                         }
7417                 }
7418 
7419                 bp = (stp->sd_rputdatafunc)(stp->sd_vnode, bp,
7420                     NULL, NULL, NULL, NULL);
7421 
7422                 if (bp == NULL)
7423                         goto retry;
7424         }
7425 
7426         if (STREAM_NEEDSERVICE(stp))
7427                 stream_runservice(stp);
7428 
7429         /*
7430          * Set HIPRI flag if message is priority.
7431          */
7432         if (type >= QPCTL)
7433                 flg = MSG_HIPRI;
7434         else
7435                 flg = MSG_BAND;
7436 
7437         /*
7438          * First process PROTO or PCPROTO blocks, if any.
7439          */
7440         if (mctlp != NULL && type != M_DATA) {
7441                 mblk_t *nbp;
7442 
7443                 *mctlp = bp;
7444                 while (bp->b_cont && bp->b_cont->b_datap->db_type != M_DATA)
7445                         bp = bp->b_cont;
7446                 nbp = bp->b_cont;
7447                 bp->b_cont = NULL;
7448                 bp = nbp;
7449         }
7450 
7451         if (bp && bp->b_datap->db_type != M_DATA) {
7452                 /*
7453                  * More PROTO blocks in msg. Will only happen if mctlp is NULL.
7454                  */
7455                 more |= MORECTL;
7456                 savemp = bp;
7457                 while (bp && bp->b_datap->db_type != M_DATA) {
7458                         savemptail = bp;
7459                         bp = bp->b_cont;
7460                 }
7461                 savemptail->b_cont = NULL;
7462         }
7463 
7464         /*
7465          * Now process DATA blocks, if any.
7466          */
7467         if (uiop == NULL) {
7468                 /* Append data to tail of mctlp */
7469 
7470                 if (mctlp != NULL) {
7471                         mblk_t **mpp = mctlp;
7472 
7473                         while (*mpp != NULL)
7474                                 mpp = &((*mpp)->b_cont);
7475                         *mpp = bp;
7476                         bp = NULL;
7477                 }
7478         } else if (uiop->uio_resid >= 0 && bp) {
7479                 size_t oldresid = uiop->uio_resid;
7480 
7481                 /*
7482                  * If a streams message is likely to consist
7483                  * of many small mblks, it is pulled up into
7484                  * one continuous chunk of memory.
7485                  * The size of the first mblk may be bogus because
7486                  * successive read() calls on the socket reduce
7487                  * the size of this mblk until it is exhausted
7488                  * and then the code walks on to the next. Thus
7489                  * the size of the mblk may not be the original size
7490                  * that was passed up, it's simply a remainder
7491                  * and hence can be very small without any
7492                  * implication that the packet is badly fragmented.
7493                  * So the size of the possible second mblk is
7494                  * used to spot a badly fragmented packet.
7495                  * see longer comment at top of page
7496                  * by mblk_pull_len declaration.
7497                  */
7498 
7499                 if (bp->b_cont != NULL && MBLKL(bp->b_cont) < mblk_pull_len) {
7500                         (void) pullupmsg(bp, -1);
7501                 }
7502 
7503                 bp = struiocopyout(bp, uiop, &error);
7504                 if (error != 0) {
7505                         if (mctlp != NULL) {
7506                                 freemsg(*mctlp);
7507                                 *mctlp = NULL;
7508                         } else
7509                                 freemsg(savemp);
7510                         mutex_enter(&stp->sd_lock);
7511                         /*
7512                          * clear stream head hi pri flag based on
7513                          * first message
7514                          */
7515                         if (!(flags & MSG_IPEEK) && (type >= QPCTL)) {
7516                                 ASSERT(type == M_PCPROTO);
7517                                 stp->sd_flag &= ~STRPRI;
7518                         }
7519                         more = 0;
7520                         goto getmout;
7521                 }
7522                 /*
7523                  * (pr == 1) indicates a partial read.
7524                  */
7525                 if (oldresid > uiop->uio_resid)
7526                         pr = 1;
7527         }
7528 
7529         if (bp) {                       /* more data blocks in msg */
7530                 more |= MOREDATA;
7531                 if (savemp)
7532                         savemptail->b_cont = bp;
7533                 else
7534                         savemp = bp;
7535         }
7536 
7537         mutex_enter(&stp->sd_lock);
7538         if (savemp) {
7539                 if (flags & (MSG_IPEEK|MSG_DISCARDTAIL)) {
7540                         /*
7541                          * When MSG_DISCARDTAIL is set or
7542                          * when peeking discard any tail. When peeking this
7543                          * is the tail of the dup that was copied out - the
7544                          * message has already been putback on the queue.
7545                          * Return MOREDATA to the caller even though the data
7546                          * is discarded. This is used by sockets (to
7547                          * set MSG_TRUNC).
7548                          */
7549                         freemsg(savemp);
7550                         if (!(flags & MSG_IPEEK) && (type >= QPCTL)) {
7551                                 ASSERT(type == M_PCPROTO);
7552                                 stp->sd_flag &= ~STRPRI;
7553                         }
7554                 } else if (pr && (savemp->b_datap->db_type == M_DATA) &&
7555                     msgnodata(savemp)) {
7556                         /*
7557                          * Avoid queuing a zero-length tail part of
7558                          * a message. pr=1 indicates that we read some of
7559                          * the message.
7560                          */
7561                         freemsg(savemp);
7562                         more &= ~MOREDATA;
7563                         if (type >= QPCTL) {
7564                                 ASSERT(type == M_PCPROTO);
7565                                 stp->sd_flag &= ~STRPRI;
7566                         }
7567                 } else {
7568                         savemp->b_band = pri;
7569                         /*
7570                          * If the first message was HIPRI and the one we're
7571                          * putting back isn't, then clear STRPRI, otherwise
7572                          * set STRPRI again.  Note that we must set STRPRI
7573                          * again since the flush logic in strrput_nondata()
7574                          * may have cleared it while we had sd_lock dropped.
7575                          */
7576 
7577                         if (type >= QPCTL) {
7578                                 ASSERT(type == M_PCPROTO);
7579                                 if (queclass(savemp) < QPCTL)
7580                                         stp->sd_flag &= ~STRPRI;
7581                                 else
7582                                         stp->sd_flag |= STRPRI;
7583                         } else if (queclass(savemp) >= QPCTL) {
7584                                 /*
7585                                  * The first message was not a HIPRI message,
7586                                  * but the one we are about to putback is.
7587                                  * For simplicitly, we do not allow for HIPRI
7588                                  * messages to be embedded in the message
7589                                  * body, so just force it to same type as
7590                                  * first message.
7591                                  */
7592                                 ASSERT(type == M_DATA || type == M_PROTO);
7593                                 ASSERT(savemp->b_datap->db_type == M_PCPROTO);
7594                                 savemp->b_datap->db_type = type;
7595                         }
7596                         if (mark != 0) {
7597                                 if ((mark & _LASTMARK) &&
7598                                     (stp->sd_mark == NULL)) {
7599                                         /*
7600                                          * If another marked message arrived
7601                                          * while sd_lock was not held sd_mark
7602                                          * would be non-NULL.
7603                                          */
7604                                         stp->sd_mark = savemp;
7605                                 }
7606                                 savemp->b_flag |= mark & ~_LASTMARK;
7607                         }
7608                         putback(stp, q, savemp, pri);
7609                 }
7610         } else if (!(flags & MSG_IPEEK)) {
7611                 /*
7612                  * The complete message was consumed.
7613                  *
7614                  * If another M_PCPROTO arrived while sd_lock was not held
7615                  * it would have been discarded since STRPRI was still set.
7616                  *
7617                  * Move the MSG*MARKNEXT information
7618                  * to the stream head just in case
7619                  * the read queue becomes empty.
7620                  * clear stream head hi pri flag based on
7621                  * first message
7622                  *
7623                  * If the stream head was at the mark
7624                  * (STRATMARK) before we dropped sd_lock above
7625                  * and some data was consumed then we have
7626                  * moved past the mark thus STRATMARK is
7627                  * cleared. However, if a message arrived in
7628                  * strrput during the copyout above causing
7629                  * STRATMARK to be set we can not clear that
7630                  * flag.
7631                  * XXX A "perimeter" would help by single-threading strrput,
7632                  * strread, strgetmsg and kstrgetmsg.
7633                  */
7634                 if (type >= QPCTL) {
7635                         ASSERT(type == M_PCPROTO);
7636                         stp->sd_flag &= ~STRPRI;
7637                 }
7638                 if (mark & (MSGMARKNEXT|MSGNOTMARKNEXT|MSGMARK)) {
7639                         if (mark & MSGMARKNEXT) {
7640                                 stp->sd_flag &= ~STRNOTATMARK;
7641                                 stp->sd_flag |= STRATMARK;
7642                         } else if (mark & MSGNOTMARKNEXT) {
7643                                 stp->sd_flag &= ~STRATMARK;
7644                                 stp->sd_flag |= STRNOTATMARK;
7645                         } else {
7646                                 stp->sd_flag &= ~(STRATMARK|STRNOTATMARK);
7647                         }
7648                 } else if (pr && (old_sd_flag & STRATMARK)) {
7649                         stp->sd_flag &= ~STRATMARK;
7650                 }
7651         }
7652 
7653         *flagsp = flg;
7654         *prip = pri;
7655 
7656         /*
7657          * Getmsg cleanup processing - if the state of the queue has changed
7658          * some signals may need to be sent and/or poll awakened.
7659          */
7660 getmout:
7661         qbackenable(q, pri);
7662 
7663         /*
7664          * We dropped the stream head lock above. Send all M_SIG messages
7665          * before processing stream head for SIGPOLL messages.
7666          */
7667         ASSERT(MUTEX_HELD(&stp->sd_lock));
7668         while ((bp = q->q_first) != NULL &&
7669             (bp->b_datap->db_type == M_SIG)) {
7670                 /*
7671                  * sd_lock is held so the content of the read queue can not
7672                  * change.
7673                  */
7674                 bp = getq(q);
7675                 ASSERT(bp != NULL && bp->b_datap->db_type == M_SIG);
7676 
7677                 strsignal_nolock(stp, *bp->b_rptr, bp->b_band);
7678                 mutex_exit(&stp->sd_lock);
7679                 freemsg(bp);
7680                 if (STREAM_NEEDSERVICE(stp))
7681                         stream_runservice(stp);
7682                 mutex_enter(&stp->sd_lock);
7683         }
7684 
7685         /*
7686          * stream head cannot change while we make the determination
7687          * whether or not to send a signal. Drop the flag to allow strrput
7688          * to send firstmsgsigs again.
7689          */
7690         stp->sd_flag &= ~STRGETINPROG;
7691 
7692         /*
7693          * If the type of message at the front of the queue changed
7694          * due to the receive the appropriate signals and pollwakeup events
7695          * are generated. The type of changes are:
7696          *      Processed a hipri message, q_first is not hipri.
7697          *      Processed a band X message, and q_first is band Y.
7698          * The generated signals and pollwakeups are identical to what
7699          * strrput() generates should the message that is now on q_first
7700          * arrive to an empty read queue.
7701          *
7702          * Note: only strrput will send a signal for a hipri message.
7703          */
7704         if ((bp = q->q_first) != NULL && !(stp->sd_flag & STRPRI)) {
7705                 strsigset_t signals = 0;
7706                 strpollset_t pollwakeups = 0;
7707 
7708                 if (flg & MSG_HIPRI) {
7709                         /*
7710                          * Removed a hipri message. Regular data at
7711                          * the front of  the queue.
7712                          */
7713                         if (bp->b_band == 0) {
7714                                 signals = S_INPUT | S_RDNORM;
7715                                 pollwakeups = POLLIN | POLLRDNORM;
7716                         } else {
7717                                 signals = S_INPUT | S_RDBAND;
7718                                 pollwakeups = POLLIN | POLLRDBAND;
7719                         }
7720                 } else if (pri != bp->b_band) {
7721                         /*
7722                          * The band is different for the new q_first.
7723                          */
7724                         if (bp->b_band == 0) {
7725                                 signals = S_RDNORM;
7726                                 pollwakeups = POLLIN | POLLRDNORM;
7727                         } else {
7728                                 signals = S_RDBAND;
7729                                 pollwakeups = POLLIN | POLLRDBAND;
7730                         }
7731                 }
7732 
7733                 if (pollwakeups != 0) {
7734                         if (pollwakeups == (POLLIN | POLLRDNORM)) {
7735                                 if (!(stp->sd_rput_opt & SR_POLLIN))
7736                                         goto no_pollwake;
7737                                 stp->sd_rput_opt &= ~SR_POLLIN;
7738                         }
7739                         mutex_exit(&stp->sd_lock);
7740                         pollwakeup(&stp->sd_pollist, pollwakeups);
7741                         mutex_enter(&stp->sd_lock);
7742                 }
7743 no_pollwake:
7744 
7745                 if (stp->sd_sigflags & signals)
7746                         strsendsig(stp->sd_siglist, signals, bp->b_band, 0);
7747         }
7748         mutex_exit(&stp->sd_lock);
7749 
7750         rvp->r_val1 = more;
7751         return (error);
7752 #undef  _LASTMARK
7753 }
7754 
7755 /*
7756  * Put a message downstream.
7757  *
7758  * NOTE: strputmsg and kstrputmsg have much of the logic in common.
7759  */
7760 int
7761 strputmsg(
7762         struct vnode *vp,
7763         struct strbuf *mctl,
7764         struct strbuf *mdata,
7765         unsigned char pri,
7766         int flag,
7767         int fmode)
7768 {
7769         struct stdata *stp;
7770         queue_t *wqp;
7771         mblk_t *mp;
7772         ssize_t msgsize;
7773         ssize_t rmin, rmax;
7774         int error;
7775         struct uio uios;
7776         struct uio *uiop = &uios;
7777         struct iovec iovs;
7778         int xpg4 = 0;
7779 
7780         ASSERT(vp->v_stream);
7781         stp = vp->v_stream;
7782         wqp = stp->sd_wrq;
7783 
7784         /*
7785          * If it is an XPG4 application, we need to send
7786          * SIGPIPE below
7787          */
7788 
7789         xpg4 = (flag & MSG_XPG4) ? 1 : 0;
7790         flag &= ~MSG_XPG4;
7791 
7792         if (AU_AUDITING())
7793                 audit_strputmsg(vp, mctl, mdata, pri, flag, fmode);
7794 
7795         mutex_enter(&stp->sd_lock);
7796 
7797         if ((error = i_straccess(stp, JCWRITE)) != 0) {
7798                 mutex_exit(&stp->sd_lock);
7799                 return (error);
7800         }
7801 
7802         if (stp->sd_flag & (STWRERR|STRHUP|STPLEX)) {
7803                 error = strwriteable(stp, B_FALSE, xpg4);
7804                 if (error != 0) {
7805                         mutex_exit(&stp->sd_lock);
7806                         return (error);
7807                 }
7808         }
7809 
7810         mutex_exit(&stp->sd_lock);
7811 
7812         /*
7813          * Check for legal flag value.
7814          */
7815         switch (flag) {
7816         case MSG_HIPRI:
7817                 if ((mctl->len < 0) || (pri != 0))
7818                         return (EINVAL);
7819                 break;
7820         case MSG_BAND:
7821                 break;
7822 
7823         default:
7824                 return (EINVAL);
7825         }
7826 
7827         TRACE_1(TR_FAC_STREAMS_FR, TR_STRPUTMSG_IN,
7828             "strputmsg in:stp %p", stp);
7829 
7830         /* get these values from those cached in the stream head */
7831         rmin = stp->sd_qn_minpsz;
7832         rmax = stp->sd_qn_maxpsz;
7833 
7834         /*
7835          * Make sure ctl and data sizes together fall within the
7836          * limits of the max and min receive packet sizes and do
7837          * not exceed system limit.
7838          */
7839         ASSERT((rmax >= 0) || (rmax == INFPSZ));
7840         if (rmax == 0) {
7841                 return (ERANGE);
7842         }
7843         /*
7844          * Use the MAXIMUM of sd_maxblk and q_maxpsz.
7845          * Needed to prevent partial failures in the strmakedata loop.
7846          */
7847         if (stp->sd_maxblk != INFPSZ && rmax != INFPSZ && rmax < stp->sd_maxblk)
7848                 rmax = stp->sd_maxblk;
7849 
7850         if ((msgsize = mdata->len) < 0) {
7851                 msgsize = 0;
7852                 rmin = 0;       /* no range check for NULL data part */
7853         }
7854         if ((msgsize < rmin) ||
7855             ((msgsize > rmax) && (rmax != INFPSZ)) ||
7856             (mctl->len > strctlsz)) {
7857                 return (ERANGE);
7858         }
7859 
7860         /*
7861          * Setup uio and iov for data part
7862          */
7863         iovs.iov_base = mdata->buf;
7864         iovs.iov_len = msgsize;
7865         uios.uio_iov = &iovs;
7866         uios.uio_iovcnt = 1;
7867         uios.uio_loffset = 0;
7868         uios.uio_segflg = UIO_USERSPACE;
7869         uios.uio_fmode = fmode;
7870         uios.uio_extflg = UIO_COPY_DEFAULT;
7871         uios.uio_resid = msgsize;
7872         uios.uio_offset = 0;
7873 
7874         /* Ignore flow control in strput for HIPRI */
7875         if (flag & MSG_HIPRI)
7876                 flag |= MSG_IGNFLOW;
7877 
7878         for (;;) {
7879                 int done = 0;
7880 
7881                 /*
7882                  * strput will always free the ctl mblk - even when strput
7883                  * fails.
7884                  */
7885                 if ((error = strmakectl(mctl, flag, fmode, &mp)) != 0) {
7886                         TRACE_3(TR_FAC_STREAMS_FR, TR_STRPUTMSG_OUT,
7887                             "strputmsg out:stp %p out %d error %d",
7888                             stp, 1, error);
7889                         return (error);
7890                 }
7891                 /*
7892                  * Verify that the whole message can be transferred by
7893                  * strput.
7894                  */
7895                 ASSERT(stp->sd_maxblk == INFPSZ ||
7896                     stp->sd_maxblk >= mdata->len);
7897 
7898                 msgsize = mdata->len;
7899                 error = strput(stp, mp, uiop, &msgsize, 0, pri, flag);
7900                 mdata->len = msgsize;
7901 
7902                 if (error == 0)
7903                         break;
7904 
7905                 if (error != EWOULDBLOCK)
7906                         goto out;
7907 
7908                 mutex_enter(&stp->sd_lock);
7909                 /*
7910                  * Check for a missed wakeup.
7911                  * Needed since strput did not hold sd_lock across
7912                  * the canputnext.
7913                  */
7914                 if (bcanputnext(wqp, pri)) {
7915                         /* Try again */
7916                         mutex_exit(&stp->sd_lock);
7917                         continue;
7918                 }
7919                 TRACE_2(TR_FAC_STREAMS_FR, TR_STRPUTMSG_WAIT,
7920                     "strputmsg wait:stp %p waits pri %d", stp, pri);
7921                 if (((error = strwaitq(stp, WRITEWAIT, (ssize_t)0, fmode, -1,
7922                     &done)) != 0) || done) {
7923                         mutex_exit(&stp->sd_lock);
7924                         TRACE_3(TR_FAC_STREAMS_FR, TR_STRPUTMSG_OUT,
7925                             "strputmsg out:q %p out %d error %d",
7926                             stp, 0, error);
7927                         return (error);
7928                 }
7929                 TRACE_1(TR_FAC_STREAMS_FR, TR_STRPUTMSG_WAKE,
7930                     "strputmsg wake:stp %p wakes", stp);
7931                 if ((error = i_straccess(stp, JCWRITE)) != 0) {
7932                         mutex_exit(&stp->sd_lock);
7933                         return (error);
7934                 }
7935                 mutex_exit(&stp->sd_lock);
7936         }
7937 out:
7938         /*
7939          * For historic reasons, applications expect EAGAIN
7940          * when data mblk could not be allocated. so change
7941          * ENOMEM back to EAGAIN
7942          */
7943         if (error == ENOMEM)
7944                 error = EAGAIN;
7945         TRACE_3(TR_FAC_STREAMS_FR, TR_STRPUTMSG_OUT,
7946             "strputmsg out:stp %p out %d error %d", stp, 2, error);
7947         return (error);
7948 }
7949 
7950 /*
7951  * Put a message downstream.
7952  * Can send only an M_PROTO/M_PCPROTO by passing in a NULL uiop.
7953  * The fmode flag (NDELAY, NONBLOCK) is the or of the flags in the uio
7954  * and the fmode parameter.
7955  *
7956  * This routine handles the consolidation private flags:
7957  *      MSG_IGNERROR    Ignore any stream head error except STPLEX.
7958  *      MSG_HOLDSIG     Hold signals while waiting for data.
7959  *      MSG_IGNFLOW     Don't check streams flow control.
7960  *
7961  * NOTE: strputmsg and kstrputmsg have much of the logic in common.
7962  */
7963 int
7964 kstrputmsg(
7965         struct vnode *vp,
7966         mblk_t *mctl,
7967         struct uio *uiop,
7968         ssize_t msgsize,
7969         unsigned char pri,
7970         int flag,
7971         int fmode)
7972 {
7973         struct stdata *stp;
7974         queue_t *wqp;
7975         ssize_t rmin, rmax;
7976         int error;
7977 
7978         ASSERT(vp->v_stream);
7979         stp = vp->v_stream;
7980         wqp = stp->sd_wrq;
7981         if (AU_AUDITING())
7982                 audit_strputmsg(vp, NULL, NULL, pri, flag, fmode);
7983         if (mctl == NULL)
7984                 return (EINVAL);
7985 
7986         mutex_enter(&stp->sd_lock);
7987 
7988         if ((error = i_straccess(stp, JCWRITE)) != 0) {
7989                 mutex_exit(&stp->sd_lock);
7990                 freemsg(mctl);
7991                 return (error);
7992         }
7993 
7994         if ((stp->sd_flag & STPLEX) || !(flag & MSG_IGNERROR)) {
7995                 if (stp->sd_flag & (STWRERR|STRHUP|STPLEX)) {
7996                         error = strwriteable(stp, B_FALSE, B_TRUE);
7997                         if (error != 0) {
7998                                 mutex_exit(&stp->sd_lock);
7999                                 freemsg(mctl);
8000                                 return (error);
8001                         }
8002                 }
8003         }
8004 
8005         mutex_exit(&stp->sd_lock);
8006 
8007         /*
8008          * Check for legal flag value.
8009          */
8010         switch (flag & (MSG_HIPRI|MSG_BAND|MSG_ANY)) {
8011         case MSG_HIPRI:
8012                 if (pri != 0) {
8013                         freemsg(mctl);
8014                         return (EINVAL);
8015                 }
8016                 break;
8017         case MSG_BAND:
8018                 break;
8019         default:
8020                 freemsg(mctl);
8021                 return (EINVAL);
8022         }
8023 
8024         TRACE_1(TR_FAC_STREAMS_FR, TR_KSTRPUTMSG_IN,
8025             "kstrputmsg in:stp %p", stp);
8026 
8027         /* get these values from those cached in the stream head */
8028         rmin = stp->sd_qn_minpsz;
8029         rmax = stp->sd_qn_maxpsz;
8030 
8031         /*
8032          * Make sure ctl and data sizes together fall within the
8033          * limits of the max and min receive packet sizes and do
8034          * not exceed system limit.
8035          */
8036         ASSERT((rmax >= 0) || (rmax == INFPSZ));
8037         if (rmax == 0) {
8038                 freemsg(mctl);
8039                 return (ERANGE);
8040         }
8041         /*
8042          * Use the MAXIMUM of sd_maxblk and q_maxpsz.
8043          * Needed to prevent partial failures in the strmakedata loop.
8044          */
8045         if (stp->sd_maxblk != INFPSZ && rmax != INFPSZ && rmax < stp->sd_maxblk)
8046                 rmax = stp->sd_maxblk;
8047 
8048         if (uiop == NULL) {
8049                 msgsize = -1;
8050                 rmin = -1;      /* no range check for NULL data part */
8051         } else {
8052                 /* Use uio flags as well as the fmode parameter flags */
8053                 fmode |= uiop->uio_fmode;
8054 
8055                 if ((msgsize < rmin) ||
8056                     ((msgsize > rmax) && (rmax != INFPSZ))) {
8057                         freemsg(mctl);
8058                         return (ERANGE);
8059                 }
8060         }
8061 
8062         /* Ignore flow control in strput for HIPRI */
8063         if (flag & MSG_HIPRI)
8064                 flag |= MSG_IGNFLOW;
8065 
8066         for (;;) {
8067                 int done = 0;
8068                 int waitflag;
8069                 mblk_t *mp;
8070 
8071                 /*
8072                  * strput will always free the ctl mblk - even when strput
8073                  * fails. If MSG_IGNFLOW is set then any error returned
8074                  * will cause us to break the loop, so we don't need a copy
8075                  * of the message. If MSG_IGNFLOW is not set, then we can
8076                  * get hit by flow control and be forced to try again. In
8077                  * this case we need to have a copy of the message. We
8078                  * do this using copymsg since the message may get modified
8079                  * by something below us.
8080                  *
8081                  * We've observed that many TPI providers do not check db_ref
8082                  * on the control messages but blindly reuse them for the
8083                  * T_OK_ACK/T_ERROR_ACK. Thus using copymsg is more
8084                  * friendly to such providers than using dupmsg. Also, note
8085                  * that sockfs uses MSG_IGNFLOW for all TPI control messages.
8086                  * Only data messages are subject to flow control, hence
8087                  * subject to this copymsg.
8088                  */
8089                 if (flag & MSG_IGNFLOW) {
8090                         mp = mctl;
8091                         mctl = NULL;
8092                 } else {
8093                         do {
8094                                 /*
8095                                  * If a message has a free pointer, the message
8096                                  * must be dupmsg to maintain this pointer.
8097                                  * Code using this facility must be sure
8098                                  * that modules below will not change the
8099                                  * contents of the dblk without checking db_ref
8100                                  * first. If db_ref is > 1, then the module
8101                                  * needs to do a copymsg first. Otherwise,
8102                                  * the contents of the dblk may become
8103                                  * inconsistent because the freesmg/freeb below
8104                                  * may end up calling atomic_add_32_nv.
8105                                  * The atomic_add_32_nv in freeb (accessing
8106                                  * all of db_ref, db_type, db_flags, and
8107                                  * db_struioflag) does not prevent other threads
8108                                  * from concurrently trying to modify e.g.
8109                                  * db_type.
8110                                  */
8111                                 if (mctl->b_datap->db_frtnp != NULL)
8112                                         mp = dupmsg(mctl);
8113                                 else
8114                                         mp = copymsg(mctl);
8115 
8116                                 if (mp != NULL)
8117                                         break;
8118 
8119                                 error = strwaitbuf(msgdsize(mctl), BPRI_MED);
8120                                 if (error) {
8121                                         freemsg(mctl);
8122                                         return (error);
8123                                 }
8124                         } while (mp == NULL);
8125                 }
8126                 /*
8127                  * Verify that all of msgsize can be transferred by
8128                  * strput.
8129                  */
8130                 ASSERT(stp->sd_maxblk == INFPSZ || stp->sd_maxblk >= msgsize);
8131                 error = strput(stp, mp, uiop, &msgsize, 0, pri, flag);
8132                 if (error == 0)
8133                         break;
8134 
8135                 if (error != EWOULDBLOCK)
8136                         goto out;
8137 
8138                 /*
8139                  * IF MSG_IGNFLOW is set we should have broken out of loop
8140                  * above.
8141                  */
8142                 ASSERT(!(flag & MSG_IGNFLOW));
8143                 mutex_enter(&stp->sd_lock);
8144                 /*
8145                  * Check for a missed wakeup.
8146                  * Needed since strput did not hold sd_lock across
8147                  * the canputnext.
8148                  */
8149                 if (bcanputnext(wqp, pri)) {
8150                         /* Try again */
8151                         mutex_exit(&stp->sd_lock);
8152                         continue;
8153                 }
8154                 TRACE_2(TR_FAC_STREAMS_FR, TR_KSTRPUTMSG_WAIT,
8155                     "kstrputmsg wait:stp %p waits pri %d", stp, pri);
8156 
8157                 waitflag = WRITEWAIT;
8158                 if (flag & (MSG_HOLDSIG|MSG_IGNERROR)) {
8159                         if (flag & MSG_HOLDSIG)
8160                                 waitflag |= STR_NOSIG;
8161                         if (flag & MSG_IGNERROR)
8162                                 waitflag |= STR_NOERROR;
8163                 }
8164                 if (((error = strwaitq(stp, waitflag,
8165                     (ssize_t)0, fmode, -1, &done)) != 0) || done) {
8166                         mutex_exit(&stp->sd_lock);
8167                         TRACE_3(TR_FAC_STREAMS_FR, TR_KSTRPUTMSG_OUT,
8168                             "kstrputmsg out:stp %p out %d error %d",
8169                             stp, 0, error);
8170                         freemsg(mctl);
8171                         return (error);
8172                 }
8173                 TRACE_1(TR_FAC_STREAMS_FR, TR_KSTRPUTMSG_WAKE,
8174                     "kstrputmsg wake:stp %p wakes", stp);
8175                 if ((error = i_straccess(stp, JCWRITE)) != 0) {
8176                         mutex_exit(&stp->sd_lock);
8177                         freemsg(mctl);
8178                         return (error);
8179                 }
8180                 mutex_exit(&stp->sd_lock);
8181         }
8182 out:
8183         freemsg(mctl);
8184         /*
8185          * For historic reasons, applications expect EAGAIN
8186          * when data mblk could not be allocated. so change
8187          * ENOMEM back to EAGAIN
8188          */
8189         if (error == ENOMEM)
8190                 error = EAGAIN;
8191         TRACE_3(TR_FAC_STREAMS_FR, TR_KSTRPUTMSG_OUT,
8192             "kstrputmsg out:stp %p out %d error %d", stp, 2, error);
8193         return (error);
8194 }
8195 
8196 /*
8197  * Determines whether the necessary conditions are set on a stream
8198  * for it to be readable, writeable, or have exceptions.
8199  *
8200  * strpoll handles the consolidation private events:
8201  *      POLLNOERR       Do not return POLLERR even if there are stream
8202  *                      head errors.
8203  *                      Used by sockfs.
8204  *      POLLRDDATA      Do not return POLLIN unless at least one message on
8205  *                      the queue contains one or more M_DATA mblks. Thus
8206  *                      when this flag is set a queue with only
8207  *                      M_PROTO/M_PCPROTO mblks does not return POLLIN.
8208  *                      Used by sockfs to ignore T_EXDATA_IND messages.
8209  *
8210  * Note: POLLRDDATA assumes that synch streams only return messages with
8211  * an M_DATA attached (i.e. not messages consisting of only
8212  * an M_PROTO/M_PCPROTO part).
8213  */
8214 int
8215 strpoll(
8216         struct stdata *stp,
8217         short events_arg,
8218         int anyyet,
8219         short *reventsp,
8220         struct pollhead **phpp)
8221 {
8222         int events = (ushort_t)events_arg;
8223         int retevents = 0;
8224         mblk_t *mp;
8225         qband_t *qbp;
8226         long sd_flags = stp->sd_flag;
8227         int headlocked = 0;
8228 
8229         /*
8230          * For performance, a single 'if' tests for most possible edge
8231          * conditions in one shot
8232          */
8233         if (sd_flags & (STPLEX | STRDERR | STWRERR)) {
8234                 if (sd_flags & STPLEX) {
8235                         *reventsp = POLLNVAL;
8236                         return (EINVAL);
8237                 }
8238                 if (((events & (POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI)) &&
8239                     (sd_flags & STRDERR)) ||
8240                     ((events & (POLLOUT | POLLWRNORM | POLLWRBAND)) &&
8241                     (sd_flags & STWRERR))) {
8242                         if (!(events & POLLNOERR)) {
8243                                 *reventsp = POLLERR;
8244                                 return (0);
8245                         }
8246                 }
8247         }
8248         if (sd_flags & STRHUP) {
8249                 retevents |= POLLHUP;
8250         } else if (events & (POLLWRNORM | POLLWRBAND)) {
8251                 queue_t *tq;
8252                 queue_t *qp = stp->sd_wrq;
8253 
8254                 claimstr(qp);
8255                 /* Find next module forward that has a service procedure */
8256                 tq = qp->q_next->q_nfsrv;
8257                 ASSERT(tq != NULL);
8258 
8259                 if (polllock(&stp->sd_pollist, QLOCK(tq)) != 0) {
8260                         releasestr(qp);
8261                         *reventsp = POLLNVAL;
8262                         return (0);
8263                 }
8264                 if (events & POLLWRNORM) {
8265                         queue_t *sqp;
8266 
8267                         if (tq->q_flag & QFULL)
8268                                 /* ensure backq svc procedure runs */
8269                                 tq->q_flag |= QWANTW;
8270                         else if ((sqp = stp->sd_struiowrq) != NULL) {
8271                                 /* Check sync stream barrier write q */
8272                                 mutex_exit(QLOCK(tq));
8273                                 if (polllock(&stp->sd_pollist,
8274                                     QLOCK(sqp)) != 0) {
8275                                         releasestr(qp);
8276                                         *reventsp = POLLNVAL;
8277                                         return (0);
8278                                 }
8279                                 if (sqp->q_flag & QFULL)
8280                                         /* ensure pollwakeup() is done */
8281                                         sqp->q_flag |= QWANTWSYNC;
8282                                 else
8283                                         retevents |= POLLOUT;
8284                                 /* More write events to process ??? */
8285                                 if (! (events & POLLWRBAND)) {
8286                                         mutex_exit(QLOCK(sqp));
8287                                         releasestr(qp);
8288                                         goto chkrd;
8289                                 }
8290                                 mutex_exit(QLOCK(sqp));
8291                                 if (polllock(&stp->sd_pollist,
8292                                     QLOCK(tq)) != 0) {
8293                                         releasestr(qp);
8294                                         *reventsp = POLLNVAL;
8295                                         return (0);
8296                                 }
8297                         } else
8298                                 retevents |= POLLOUT;
8299                 }
8300                 if (events & POLLWRBAND) {
8301                         qbp = tq->q_bandp;
8302                         if (qbp) {
8303                                 while (qbp) {
8304                                         if (qbp->qb_flag & QB_FULL)
8305                                                 qbp->qb_flag |= QB_WANTW;
8306                                         else
8307                                                 retevents |= POLLWRBAND;
8308                                         qbp = qbp->qb_next;
8309                                 }
8310                         } else {
8311                                 retevents |= POLLWRBAND;
8312                         }
8313                 }
8314                 mutex_exit(QLOCK(tq));
8315                 releasestr(qp);
8316         }
8317 chkrd:
8318         if (sd_flags & STRPRI) {
8319                 retevents |= (events & POLLPRI);
8320         } else if (events & (POLLRDNORM | POLLRDBAND | POLLIN)) {
8321                 queue_t *qp = _RD(stp->sd_wrq);
8322                 int normevents = (events & (POLLIN | POLLRDNORM));
8323 
8324                 /*
8325                  * Note: Need to do polllock() here since ps_lock may be
8326                  * held. See bug 4191544.
8327                  */
8328                 if (polllock(&stp->sd_pollist, &stp->sd_lock) != 0) {
8329                         *reventsp = POLLNVAL;
8330                         return (0);
8331                 }
8332                 headlocked = 1;
8333                 mp = qp->q_first;
8334                 while (mp) {
8335                         /*
8336                          * For POLLRDDATA we scan b_cont and b_next until we
8337                          * find an M_DATA.
8338                          */
8339                         if ((events & POLLRDDATA) &&
8340                             mp->b_datap->db_type != M_DATA) {
8341                                 mblk_t *nmp = mp->b_cont;
8342 
8343                                 while (nmp != NULL &&
8344                                     nmp->b_datap->db_type != M_DATA)
8345                                         nmp = nmp->b_cont;
8346                                 if (nmp == NULL) {
8347                                         mp = mp->b_next;
8348                                         continue;
8349                                 }
8350                         }
8351                         if (mp->b_band == 0)
8352                                 retevents |= normevents;
8353                         else
8354                                 retevents |= (events & (POLLIN | POLLRDBAND));
8355                         break;
8356                 }
8357                 if (! (retevents & normevents) &&
8358                     (stp->sd_wakeq & RSLEEP)) {
8359                         /*
8360                          * Sync stream barrier read queue has data.
8361                          */
8362                         retevents |= normevents;
8363                 }
8364                 /* Treat eof as normal data */
8365                 if (sd_flags & STREOF)
8366                         retevents |= normevents;
8367         }
8368 
8369         *reventsp = (short)retevents;
8370         if (retevents && !(events & POLLET)) {
8371                 if (headlocked)
8372                         mutex_exit(&stp->sd_lock);
8373                 return (0);
8374         }
8375 
8376         /*
8377          * If poll() has not found any events yet, set up event cell
8378          * to wake up the poll if a requested event occurs on this
8379          * stream.  Check for collisions with outstanding poll requests.
8380          */
8381         if (!anyyet) {
8382                 *phpp = &stp->sd_pollist;
8383                 if (headlocked == 0) {
8384                         if (polllock(&stp->sd_pollist, &stp->sd_lock) != 0) {
8385                                 *reventsp = POLLNVAL;
8386                                 return (0);
8387                         }
8388                         headlocked = 1;
8389                 }
8390                 stp->sd_rput_opt |= SR_POLLIN;
8391         }
8392         if (headlocked)
8393                 mutex_exit(&stp->sd_lock);
8394         return (0);
8395 }
8396 
8397 /*
8398  * The purpose of putback() is to assure sleeping polls/reads
8399  * are awakened when there are no new messages arriving at the,
8400  * stream head, and a message is placed back on the read queue.
8401  *
8402  * sd_lock must be held when messages are placed back on stream
8403  * head.  (getq() holds sd_lock when it removes messages from
8404  * the queue)
8405  */
8406 
8407 static void
8408 putback(struct stdata *stp, queue_t *q, mblk_t *bp, int band)
8409 {
8410         mblk_t  *qfirst;
8411         ASSERT(MUTEX_HELD(&stp->sd_lock));
8412 
8413         /*
8414          * As a result of lock-step ordering around q_lock and sd_lock,
8415          * it's possible for function calls like putnext() and
8416          * canputnext() to get an inaccurate picture of how much
8417          * data is really being processed at the stream head.
8418          * We only consolidate with existing messages on the queue
8419          * if the length of the message we want to put back is smaller
8420          * than the queue hiwater mark.
8421          */
8422         if ((stp->sd_rput_opt & SR_CONSOL_DATA) &&
8423             (DB_TYPE(bp) == M_DATA) && ((qfirst = q->q_first) != NULL) &&
8424             (DB_TYPE(qfirst) == M_DATA) &&
8425             ((qfirst->b_flag & (MSGMARK|MSGDELIM)) == 0) &&
8426             ((bp->b_flag & (MSGMARK|MSGDELIM|MSGMARKNEXT)) == 0) &&
8427             (mp_cont_len(bp, NULL) < q->q_hiwat)) {
8428                 /*
8429                  * We use the same logic as defined in strrput()
8430                  * but in reverse as we are putting back onto the
8431                  * queue and want to retain byte ordering.
8432                  * Consolidate M_DATA messages with M_DATA ONLY.
8433                  * strrput() allows the consolidation of M_DATA onto
8434                  * M_PROTO | M_PCPROTO but not the other way round.
8435                  *
8436                  * The consolidation does not take place if the message
8437                  * we are returning to the queue is marked with either
8438                  * of the marks or the delim flag or if q_first
8439                  * is marked with MSGMARK. The MSGMARK check is needed to
8440                  * handle the odd semantics of MSGMARK where essentially
8441                  * the whole message is to be treated as marked.
8442                  * Carry any MSGMARKNEXT and MSGNOTMARKNEXT from q_first
8443                  * to the front of the b_cont chain.
8444                  */
8445                 rmvq_noenab(q, qfirst);
8446 
8447                 /*
8448                  * The first message in the b_cont list
8449                  * tracks MSGMARKNEXT and MSGNOTMARKNEXT.
8450                  * We need to handle the case where we
8451                  * are appending:
8452                  *
8453                  * 1) a MSGMARKNEXT to a MSGNOTMARKNEXT.
8454                  * 2) a MSGMARKNEXT to a plain message.
8455                  * 3) a MSGNOTMARKNEXT to a plain message
8456                  * 4) a MSGNOTMARKNEXT to a MSGNOTMARKNEXT
8457                  *    message.
8458                  *
8459                  * Thus we never append a MSGMARKNEXT or
8460                  * MSGNOTMARKNEXT to a MSGMARKNEXT message.
8461                  */
8462                 if (qfirst->b_flag & MSGMARKNEXT) {
8463                         bp->b_flag |= MSGMARKNEXT;
8464                         bp->b_flag &= ~MSGNOTMARKNEXT;
8465                         qfirst->b_flag &= ~MSGMARKNEXT;
8466                 } else if (qfirst->b_flag & MSGNOTMARKNEXT) {
8467                         bp->b_flag |= MSGNOTMARKNEXT;
8468                         qfirst->b_flag &= ~MSGNOTMARKNEXT;
8469                 }
8470 
8471                 linkb(bp, qfirst);
8472         }
8473         (void) putbq(q, bp);
8474 
8475         /*
8476          * A message may have come in when the sd_lock was dropped in the
8477          * calling routine. If this is the case and STR*ATMARK info was
8478          * received, need to move that from the stream head to the q_last
8479          * so that SIOCATMARK can return the proper value.
8480          */
8481         if (stp->sd_flag & (STRATMARK | STRNOTATMARK)) {
8482                 unsigned short *flagp = &q->q_last->b_flag;
8483                 uint_t b_flag = (uint_t)*flagp;
8484 
8485                 if (stp->sd_flag & STRATMARK) {
8486                         b_flag &= ~MSGNOTMARKNEXT;
8487                         b_flag |= MSGMARKNEXT;
8488                         stp->sd_flag &= ~STRATMARK;
8489                 } else {
8490                         b_flag &= ~MSGMARKNEXT;
8491                         b_flag |= MSGNOTMARKNEXT;
8492                         stp->sd_flag &= ~STRNOTATMARK;
8493                 }
8494                 *flagp = (unsigned short) b_flag;
8495         }
8496 
8497 #ifdef  DEBUG
8498         /*
8499          * Make sure that the flags are not messed up.
8500          */
8501         {
8502                 mblk_t *mp;
8503                 mp = q->q_last;
8504                 while (mp != NULL) {
8505                         ASSERT((mp->b_flag & (MSGMARKNEXT|MSGNOTMARKNEXT)) !=
8506                             (MSGMARKNEXT|MSGNOTMARKNEXT));
8507                         mp = mp->b_cont;
8508                 }
8509         }
8510 #endif
8511         if (q->q_first == bp) {
8512                 short pollevents;
8513 
8514                 if (stp->sd_flag & RSLEEP) {
8515                         stp->sd_flag &= ~RSLEEP;
8516                         cv_broadcast(&q->q_wait);
8517                 }
8518                 if (stp->sd_flag & STRPRI) {
8519                         pollevents = POLLPRI;
8520                 } else {
8521                         if (band == 0) {
8522                                 if (!(stp->sd_rput_opt & SR_POLLIN))
8523                                         return;
8524                                 stp->sd_rput_opt &= ~SR_POLLIN;
8525                                 pollevents = POLLIN | POLLRDNORM;
8526                         } else {
8527                                 pollevents = POLLIN | POLLRDBAND;
8528                         }
8529                 }
8530                 mutex_exit(&stp->sd_lock);
8531                 pollwakeup(&stp->sd_pollist, pollevents);
8532                 mutex_enter(&stp->sd_lock);
8533         }
8534 }
8535 
8536 /*
8537  * Return the held vnode attached to the stream head of a
8538  * given queue
8539  * It is the responsibility of the calling routine to ensure
8540  * that the queue does not go away (e.g. pop).
8541  */
8542 vnode_t *
8543 strq2vp(queue_t *qp)
8544 {
8545         vnode_t *vp;
8546         vp = STREAM(qp)->sd_vnode;
8547         ASSERT(vp != NULL);
8548         VN_HOLD(vp);
8549         return (vp);
8550 }
8551 
8552 /*
8553  * return the stream head write queue for the given vp
8554  * It is the responsibility of the calling routine to ensure
8555  * that the stream or vnode do not close.
8556  */
8557 queue_t *
8558 strvp2wq(vnode_t *vp)
8559 {
8560         ASSERT(vp->v_stream != NULL);
8561         return (vp->v_stream->sd_wrq);
8562 }
8563 
8564 /*
8565  * pollwakeup stream head
8566  * It is the responsibility of the calling routine to ensure
8567  * that the stream or vnode do not close.
8568  */
8569 void
8570 strpollwakeup(vnode_t *vp, short event)
8571 {
8572         ASSERT(vp->v_stream);
8573         pollwakeup(&vp->v_stream->sd_pollist, event);
8574 }
8575 
8576 /*
8577  * Mate the stream heads of two vnodes together. If the two vnodes are the
8578  * same, we just make the write-side point at the read-side -- otherwise,
8579  * we do a full mate.  Only works on vnodes associated with streams that are
8580  * still being built and thus have only a stream head.
8581  */
8582 void
8583 strmate(vnode_t *vp1, vnode_t *vp2)
8584 {
8585         queue_t *wrq1 = strvp2wq(vp1);
8586         queue_t *wrq2 = strvp2wq(vp2);
8587 
8588         /*
8589          * Verify that there are no modules on the stream yet.  We also
8590          * rely on the stream head always having a service procedure to
8591          * avoid tweaking q_nfsrv.
8592          */
8593         ASSERT(wrq1->q_next == NULL && wrq2->q_next == NULL);
8594         ASSERT(wrq1->q_qinfo->qi_srvp != NULL);
8595         ASSERT(wrq2->q_qinfo->qi_srvp != NULL);
8596 
8597         /*
8598          * If the queues are the same, just twist; otherwise do a full mate.
8599          */
8600         if (wrq1 == wrq2) {
8601                 wrq1->q_next = _RD(wrq1);
8602         } else {
8603                 wrq1->q_next = _RD(wrq2);
8604                 wrq2->q_next = _RD(wrq1);
8605                 STREAM(wrq1)->sd_mate = STREAM(wrq2);
8606                 STREAM(wrq1)->sd_flag |= STRMATE;
8607                 STREAM(wrq2)->sd_mate = STREAM(wrq1);
8608                 STREAM(wrq2)->sd_flag |= STRMATE;
8609         }
8610 }
8611 
8612 /*
8613  * XXX will go away when console is correctly fixed.
8614  * Clean up the console PIDS, from previous I_SETSIG,
8615  * called only for cnopen which never calls strclean().
8616  */
8617 void
8618 str_cn_clean(struct vnode *vp)
8619 {
8620         strsig_t *ssp, *pssp, *tssp;
8621         struct stdata *stp;
8622         struct pid  *pidp;
8623         int update = 0;
8624 
8625         ASSERT(vp->v_stream);
8626         stp = vp->v_stream;
8627         pssp = NULL;
8628         mutex_enter(&stp->sd_lock);
8629         ssp = stp->sd_siglist;
8630         while (ssp) {
8631                 mutex_enter(&pidlock);
8632                 pidp = ssp->ss_pidp;
8633                 /*
8634                  * Get rid of PID if the proc is gone.
8635                  */
8636                 if (pidp->pid_prinactive) {
8637                         tssp = ssp->ss_next;
8638                         if (pssp)
8639                                 pssp->ss_next = tssp;
8640                         else
8641                                 stp->sd_siglist = tssp;
8642                         ASSERT(pidp->pid_ref <= 1);
8643                         PID_RELE(ssp->ss_pidp);
8644                         mutex_exit(&pidlock);
8645                         kmem_free(ssp, sizeof (strsig_t));
8646                         update = 1;
8647                         ssp = tssp;
8648                         continue;
8649                 } else
8650                         mutex_exit(&pidlock);
8651                 pssp = ssp;
8652                 ssp = ssp->ss_next;
8653         }
8654         if (update) {
8655                 stp->sd_sigflags = 0;
8656                 for (ssp = stp->sd_siglist; ssp; ssp = ssp->ss_next)
8657                         stp->sd_sigflags |= ssp->ss_events;
8658         }
8659         mutex_exit(&stp->sd_lock);
8660 }
8661 
8662 /*
8663  * Return B_TRUE if there is data in the message, B_FALSE otherwise.
8664  */
8665 static boolean_t
8666 msghasdata(mblk_t *bp)
8667 {
8668         for (; bp; bp = bp->b_cont)
8669                 if (bp->b_datap->db_type == M_DATA) {
8670                         ASSERT(bp->b_wptr >= bp->b_rptr);
8671                         if (bp->b_wptr > bp->b_rptr)
8672                                 return (B_TRUE);
8673                 }
8674         return (B_FALSE);
8675 }