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 
  22 /*
  23  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Portions Copyright 2011 iXsystems, Inc
  25  * Copyright (c) 2013, 2017 by Delphix. All rights reserved.
  26  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
  27  * Copyright (c) 2014 Integros [integros.com]
  28  * Copyright 2019 Joyent, Inc.
  29  */
  30 
  31 #include <sys/zfs_context.h>
  32 #include <sys/types.h>
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/sysmacros.h>
  36 #include <sys/dmu.h>
  37 #include <sys/dmu_impl.h>
  38 #include <sys/dmu_objset.h>
  39 #include <sys/dmu_tx.h>
  40 #include <sys/dbuf.h>
  41 #include <sys/dnode.h>
  42 #include <sys/zap.h>
  43 #include <sys/sa.h>
  44 #include <sys/sunddi.h>
  45 #include <sys/sa_impl.h>
  46 #include <sys/dnode.h>
  47 #include <sys/errno.h>
  48 #include <sys/zfs_context.h>
  49 
  50 #ifdef _KERNEL
  51 #include <sys/zfs_znode.h>
  52 #endif
  53 
  54 /*
  55  * ZFS System attributes:
  56  *
  57  * A generic mechanism to allow for arbitrary attributes
  58  * to be stored in a dnode.  The data will be stored in the bonus buffer of
  59  * the dnode and if necessary a special "spill" block will be used to handle
  60  * overflow situations.  The spill block will be sized to fit the data
  61  * from 512 - 128K.  When a spill block is used the BP (blkptr_t) for the
  62  * spill block is stored at the end of the current bonus buffer.  Any
  63  * attributes that would be in the way of the blkptr_t will be relocated
  64  * into the spill block.
  65  *
  66  * Attribute registration:
  67  *
  68  * Stored persistently on a per dataset basis
  69  * a mapping between attribute "string" names and their actual attribute
  70  * numeric values, length, and byteswap function.  The names are only used
  71  * during registration.  All  attributes are known by their unique attribute
  72  * id value.  If an attribute can have a variable size then the value
  73  * 0 will be used to indicate this.
  74  *
  75  * Attribute Layout:
  76  *
  77  * Attribute layouts are a way to compactly store multiple attributes, but
  78  * without taking the overhead associated with managing each attribute
  79  * individually.  Since you will typically have the same set of attributes
  80  * stored in the same order a single table will be used to represent that
  81  * layout.  The ZPL for example will usually have only about 10 different
  82  * layouts (regular files, device files, symlinks,
  83  * regular files + scanstamp, files/dir with extended attributes, and then
  84  * you have the possibility of all of those minus ACL, because it would
  85  * be kicked out into the spill block)
  86  *
  87  * Layouts are simply an array of the attributes and their
  88  * ordering i.e. [0, 1, 4, 5, 2]
  89  *
  90  * Each distinct layout is given a unique layout number and that is whats
  91  * stored in the header at the beginning of the SA data buffer.
  92  *
  93  * A layout only covers a single dbuf (bonus or spill).  If a set of
  94  * attributes is split up between the bonus buffer and a spill buffer then
  95  * two different layouts will be used.  This allows us to byteswap the
  96  * spill without looking at the bonus buffer and keeps the on disk format of
  97  * the bonus and spill buffer the same.
  98  *
  99  * Adding a single attribute will cause the entire set of attributes to
 100  * be rewritten and could result in a new layout number being constructed
 101  * as part of the rewrite if no such layout exists for the new set of
 102  * attribues.  The new attribute will be appended to the end of the already
 103  * existing attributes.
 104  *
 105  * Both the attribute registration and attribute layout information are
 106  * stored in normal ZAP attributes.  Their should be a small number of
 107  * known layouts and the set of attributes is assumed to typically be quite
 108  * small.
 109  *
 110  * The registered attributes and layout "table" information is maintained
 111  * in core and a special "sa_os_t" is attached to the objset_t.
 112  *
 113  * A special interface is provided to allow for quickly applying
 114  * a large set of attributes at once.  sa_replace_all_by_template() is
 115  * used to set an array of attributes.  This is used by the ZPL when
 116  * creating a brand new file.  The template that is passed into the function
 117  * specifies the attribute, size for variable length attributes, location of
 118  * data and special "data locator" function if the data isn't in a contiguous
 119  * location.
 120  *
 121  * Byteswap implications:
 122  *
 123  * Since the SA attributes are not entirely self describing we can't do
 124  * the normal byteswap processing.  The special ZAP layout attribute and
 125  * attribute registration attributes define the byteswap function and the
 126  * size of the attributes, unless it is variable sized.
 127  * The normal ZFS byteswapping infrastructure assumes you don't need
 128  * to read any objects in order to do the necessary byteswapping.  Whereas
 129  * SA attributes can only be properly byteswapped if the dataset is opened
 130  * and the layout/attribute ZAP attributes are available.  Because of this
 131  * the SA attributes will be byteswapped when they are first accessed by
 132  * the SA code that will read the SA data.
 133  */
 134 
 135 typedef void (sa_iterfunc_t)(void *hdr, void *addr, sa_attr_type_t,
 136     uint16_t length, int length_idx, boolean_t, void *userp);
 137 
 138 static int sa_build_index(sa_handle_t *hdl, sa_buf_type_t buftype);
 139 static void sa_idx_tab_hold(objset_t *os, sa_idx_tab_t *idx_tab);
 140 static sa_idx_tab_t *sa_find_idx_tab(objset_t *os, dmu_object_type_t bonustype,
 141     sa_hdr_phys_t *hdr);
 142 static void sa_idx_tab_rele(objset_t *os, void *arg);
 143 static void sa_copy_data(sa_data_locator_t *func, void *start, void *target,
 144     int buflen);
 145 static int sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr,
 146     sa_data_op_t action, sa_data_locator_t *locator, void *datastart,
 147     uint16_t buflen, dmu_tx_t *tx);
 148 
 149 arc_byteswap_func_t *sa_bswap_table[] = {
 150         byteswap_uint64_array,
 151         byteswap_uint32_array,
 152         byteswap_uint16_array,
 153         byteswap_uint8_array,
 154         zfs_acl_byteswap,
 155 };
 156 
 157 #define SA_COPY_DATA(f, s, t, l) \
 158         { \
 159                 if (f == NULL) { \
 160                         if (l == 8) { \
 161                                 *(uint64_t *)t = *(uint64_t *)s; \
 162                         } else if (l == 16) { \
 163                                 *(uint64_t *)t = *(uint64_t *)s; \
 164                                 *(uint64_t *)((uintptr_t)t + 8) = \
 165                                     *(uint64_t *)((uintptr_t)s + 8); \
 166                         } else { \
 167                                 bcopy(s, t, l); \
 168                         } \
 169                 } else \
 170                         sa_copy_data(f, s, t, l); \
 171         }
 172 
 173 /*
 174  * This table is fixed and cannot be changed.  Its purpose is to
 175  * allow the SA code to work with both old/new ZPL file systems.
 176  * It contains the list of legacy attributes.  These attributes aren't
 177  * stored in the "attribute" registry zap objects, since older ZPL file systems
 178  * won't have the registry.  Only objsets of type ZFS_TYPE_FILESYSTEM will
 179  * use this static table.
 180  */
 181 sa_attr_reg_t sa_legacy_attrs[] = {
 182         {"ZPL_ATIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 0},
 183         {"ZPL_MTIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 1},
 184         {"ZPL_CTIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 2},
 185         {"ZPL_CRTIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 3},
 186         {"ZPL_GEN", sizeof (uint64_t), SA_UINT64_ARRAY, 4},
 187         {"ZPL_MODE", sizeof (uint64_t), SA_UINT64_ARRAY, 5},
 188         {"ZPL_SIZE", sizeof (uint64_t), SA_UINT64_ARRAY, 6},
 189         {"ZPL_PARENT", sizeof (uint64_t), SA_UINT64_ARRAY, 7},
 190         {"ZPL_LINKS", sizeof (uint64_t), SA_UINT64_ARRAY, 8},
 191         {"ZPL_XATTR", sizeof (uint64_t), SA_UINT64_ARRAY, 9},
 192         {"ZPL_RDEV", sizeof (uint64_t), SA_UINT64_ARRAY, 10},
 193         {"ZPL_FLAGS", sizeof (uint64_t), SA_UINT64_ARRAY, 11},
 194         {"ZPL_UID", sizeof (uint64_t), SA_UINT64_ARRAY, 12},
 195         {"ZPL_GID", sizeof (uint64_t), SA_UINT64_ARRAY, 13},
 196         {"ZPL_PAD", sizeof (uint64_t) * 4, SA_UINT64_ARRAY, 14},
 197         {"ZPL_ZNODE_ACL", 88, SA_UINT8_ARRAY, 15},
 198 };
 199 
 200 /*
 201  * This is only used for objects of type DMU_OT_ZNODE
 202  */
 203 sa_attr_type_t sa_legacy_zpl_layout[] = {
 204     0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
 205 };
 206 
 207 /*
 208  * Special dummy layout used for buffers with no attributes.
 209  */
 210 sa_attr_type_t sa_dummy_zpl_layout[] = { 0 };
 211 
 212 static int sa_legacy_attr_count = 16;
 213 static kmem_cache_t *sa_cache = NULL;
 214 
 215 /*ARGSUSED*/
 216 static int
 217 sa_cache_constructor(void *buf, void *unused, int kmflag)
 218 {
 219         sa_handle_t *hdl = buf;
 220 
 221         mutex_init(&hdl->sa_lock, NULL, MUTEX_DEFAULT, NULL);
 222         return (0);
 223 }
 224 
 225 /*ARGSUSED*/
 226 static void
 227 sa_cache_destructor(void *buf, void *unused)
 228 {
 229         sa_handle_t *hdl = buf;
 230         mutex_destroy(&hdl->sa_lock);
 231 }
 232 
 233 void
 234 sa_cache_init(void)
 235 {
 236         sa_cache = kmem_cache_create("sa_cache",
 237             sizeof (sa_handle_t), 0, sa_cache_constructor,
 238             sa_cache_destructor, NULL, NULL, NULL, 0);
 239 }
 240 
 241 void
 242 sa_cache_fini(void)
 243 {
 244         if (sa_cache)
 245                 kmem_cache_destroy(sa_cache);
 246 }
 247 
 248 static int
 249 layout_num_compare(const void *arg1, const void *arg2)
 250 {
 251         const sa_lot_t *node1 = (const sa_lot_t *)arg1;
 252         const sa_lot_t *node2 = (const sa_lot_t *)arg2;
 253 
 254         return (AVL_CMP(node1->lot_num, node2->lot_num));
 255 }
 256 
 257 static int
 258 layout_hash_compare(const void *arg1, const void *arg2)
 259 {
 260         const sa_lot_t *node1 = (const sa_lot_t *)arg1;
 261         const sa_lot_t *node2 = (const sa_lot_t *)arg2;
 262 
 263         int cmp = AVL_CMP(node1->lot_hash, node2->lot_hash);
 264         if (likely(cmp))
 265                 return (cmp);
 266 
 267         return (AVL_CMP(node1->lot_instance, node2->lot_instance));
 268 }
 269 
 270 boolean_t
 271 sa_layout_equal(sa_lot_t *tbf, sa_attr_type_t *attrs, int count)
 272 {
 273         int i;
 274 
 275         if (count != tbf->lot_attr_count)
 276                 return (1);
 277 
 278         for (i = 0; i != count; i++) {
 279                 if (attrs[i] != tbf->lot_attrs[i])
 280                         return (1);
 281         }
 282         return (0);
 283 }
 284 
 285 #define SA_ATTR_HASH(attr) (zfs_crc64_table[(-1ULL ^ attr) & 0xFF])
 286 
 287 static uint64_t
 288 sa_layout_info_hash(sa_attr_type_t *attrs, int attr_count)
 289 {
 290         int i;
 291         uint64_t crc = -1ULL;
 292 
 293         for (i = 0; i != attr_count; i++)
 294                 crc ^= SA_ATTR_HASH(attrs[i]);
 295 
 296         return (crc);
 297 }
 298 
 299 static int
 300 sa_get_spill(sa_handle_t *hdl)
 301 {
 302         int rc;
 303         if (hdl->sa_spill == NULL) {
 304                 if ((rc = dmu_spill_hold_existing(hdl->sa_bonus, NULL,
 305                     &hdl->sa_spill)) == 0)
 306                         VERIFY(0 == sa_build_index(hdl, SA_SPILL));
 307         } else {
 308                 rc = 0;
 309         }
 310 
 311         return (rc);
 312 }
 313 
 314 /*
 315  * Main attribute lookup/update function
 316  * returns 0 for success or non zero for failures
 317  *
 318  * Operates on bulk array, first failure will abort further processing
 319  */
 320 int
 321 sa_attr_op(sa_handle_t *hdl, sa_bulk_attr_t *bulk, int count,
 322     sa_data_op_t data_op, dmu_tx_t *tx)
 323 {
 324         sa_os_t *sa = hdl->sa_os->os_sa;
 325         int i;
 326         int error = 0;
 327         sa_buf_type_t buftypes;
 328 
 329         buftypes = 0;
 330 
 331         ASSERT(count > 0);
 332         for (i = 0; i != count; i++) {
 333                 ASSERT(bulk[i].sa_attr <= hdl->sa_os->os_sa->sa_num_attrs);
 334 
 335                 bulk[i].sa_addr = NULL;
 336                 /* First check the bonus buffer */
 337 
 338                 if (hdl->sa_bonus_tab && TOC_ATTR_PRESENT(
 339                     hdl->sa_bonus_tab->sa_idx_tab[bulk[i].sa_attr])) {
 340                         SA_ATTR_INFO(sa, hdl->sa_bonus_tab,
 341                             SA_GET_HDR(hdl, SA_BONUS),
 342                             bulk[i].sa_attr, bulk[i], SA_BONUS, hdl);
 343                         if (tx && !(buftypes & SA_BONUS)) {
 344                                 dmu_buf_will_dirty(hdl->sa_bonus, tx);
 345                                 buftypes |= SA_BONUS;
 346                         }
 347                 }
 348                 if (bulk[i].sa_addr == NULL &&
 349                     ((error = sa_get_spill(hdl)) == 0)) {
 350                         if (TOC_ATTR_PRESENT(
 351                             hdl->sa_spill_tab->sa_idx_tab[bulk[i].sa_attr])) {
 352                                 SA_ATTR_INFO(sa, hdl->sa_spill_tab,
 353                                     SA_GET_HDR(hdl, SA_SPILL),
 354                                     bulk[i].sa_attr, bulk[i], SA_SPILL, hdl);
 355                                 if (tx && !(buftypes & SA_SPILL) &&
 356                                     bulk[i].sa_size == bulk[i].sa_length) {
 357                                         dmu_buf_will_dirty(hdl->sa_spill, tx);
 358                                         buftypes |= SA_SPILL;
 359                                 }
 360                         }
 361                 }
 362                 if (error && error != ENOENT) {
 363                         return ((error == ECKSUM) ? EIO : error);
 364                 }
 365 
 366                 switch (data_op) {
 367                 case SA_LOOKUP:
 368                         if (bulk[i].sa_addr == NULL)
 369                                 return (SET_ERROR(ENOENT));
 370                         if (bulk[i].sa_data) {
 371                                 SA_COPY_DATA(bulk[i].sa_data_func,
 372                                     bulk[i].sa_addr, bulk[i].sa_data,
 373                                     bulk[i].sa_size);
 374                         }
 375                         continue;
 376 
 377                 case SA_UPDATE:
 378                         /* existing rewrite of attr */
 379                         if (bulk[i].sa_addr &&
 380                             bulk[i].sa_size == bulk[i].sa_length) {
 381                                 SA_COPY_DATA(bulk[i].sa_data_func,
 382                                     bulk[i].sa_data, bulk[i].sa_addr,
 383                                     bulk[i].sa_length);
 384                                 continue;
 385                         } else if (bulk[i].sa_addr) { /* attr size change */
 386                                 error = sa_modify_attrs(hdl, bulk[i].sa_attr,
 387                                     SA_REPLACE, bulk[i].sa_data_func,
 388                                     bulk[i].sa_data, bulk[i].sa_length, tx);
 389                         } else { /* adding new attribute */
 390                                 error = sa_modify_attrs(hdl, bulk[i].sa_attr,
 391                                     SA_ADD, bulk[i].sa_data_func,
 392                                     bulk[i].sa_data, bulk[i].sa_length, tx);
 393                         }
 394                         if (error)
 395                                 return (error);
 396                         break;
 397                 }
 398         }
 399         return (error);
 400 }
 401 
 402 static sa_lot_t *
 403 sa_add_layout_entry(objset_t *os, sa_attr_type_t *attrs, int attr_count,
 404     uint64_t lot_num, uint64_t hash, boolean_t zapadd, dmu_tx_t *tx)
 405 {
 406         sa_os_t *sa = os->os_sa;
 407         sa_lot_t *tb, *findtb;
 408         int i;
 409         avl_index_t loc;
 410 
 411         ASSERT(MUTEX_HELD(&sa->sa_lock));
 412         tb = kmem_zalloc(sizeof (sa_lot_t), KM_SLEEP);
 413         tb->lot_attr_count = attr_count;
 414         tb->lot_attrs = kmem_alloc(sizeof (sa_attr_type_t) * attr_count,
 415             KM_SLEEP);
 416         bcopy(attrs, tb->lot_attrs, sizeof (sa_attr_type_t) * attr_count);
 417         tb->lot_num = lot_num;
 418         tb->lot_hash = hash;
 419         tb->lot_instance = 0;
 420 
 421         if (zapadd) {
 422                 char attr_name[8];
 423 
 424                 if (sa->sa_layout_attr_obj == 0) {
 425                         sa->sa_layout_attr_obj = zap_create_link(os,
 426                             DMU_OT_SA_ATTR_LAYOUTS,
 427                             sa->sa_master_obj, SA_LAYOUTS, tx);
 428                 }
 429 
 430                 (void) snprintf(attr_name, sizeof (attr_name),
 431                     "%d", (int)lot_num);
 432                 VERIFY(0 == zap_update(os, os->os_sa->sa_layout_attr_obj,
 433                     attr_name, 2, attr_count, attrs, tx));
 434         }
 435 
 436         list_create(&tb->lot_idx_tab, sizeof (sa_idx_tab_t),
 437             offsetof(sa_idx_tab_t, sa_next));
 438 
 439         for (i = 0; i != attr_count; i++) {
 440                 if (sa->sa_attr_table[tb->lot_attrs[i]].sa_length == 0)
 441                         tb->lot_var_sizes++;
 442         }
 443 
 444         avl_add(&sa->sa_layout_num_tree, tb);
 445 
 446         /* verify we don't have a hash collision */
 447         if ((findtb = avl_find(&sa->sa_layout_hash_tree, tb, &loc)) != NULL) {
 448                 for (; findtb && findtb->lot_hash == hash;
 449                     findtb = AVL_NEXT(&sa->sa_layout_hash_tree, findtb)) {
 450                         if (findtb->lot_instance != tb->lot_instance)
 451                                 break;
 452                         tb->lot_instance++;
 453                 }
 454         }
 455         avl_add(&sa->sa_layout_hash_tree, tb);
 456         return (tb);
 457 }
 458 
 459 static void
 460 sa_find_layout(objset_t *os, uint64_t hash, sa_attr_type_t *attrs,
 461     int count, dmu_tx_t *tx, sa_lot_t **lot)
 462 {
 463         sa_lot_t *tb, tbsearch;
 464         avl_index_t loc;
 465         sa_os_t *sa = os->os_sa;
 466         boolean_t found = B_FALSE;
 467 
 468         mutex_enter(&sa->sa_lock);
 469         tbsearch.lot_hash = hash;
 470         tbsearch.lot_instance = 0;
 471         tb = avl_find(&sa->sa_layout_hash_tree, &tbsearch, &loc);
 472         if (tb) {
 473                 for (; tb && tb->lot_hash == hash;
 474                     tb = AVL_NEXT(&sa->sa_layout_hash_tree, tb)) {
 475                         if (sa_layout_equal(tb, attrs, count) == 0) {
 476                                 found = B_TRUE;
 477                                 break;
 478                         }
 479                 }
 480         }
 481         if (!found) {
 482                 tb = sa_add_layout_entry(os, attrs, count,
 483                     avl_numnodes(&sa->sa_layout_num_tree), hash, B_TRUE, tx);
 484         }
 485         mutex_exit(&sa->sa_lock);
 486         *lot = tb;
 487 }
 488 
 489 static int
 490 sa_resize_spill(sa_handle_t *hdl, uint32_t size, dmu_tx_t *tx)
 491 {
 492         int error;
 493         uint32_t blocksize;
 494 
 495         if (size == 0) {
 496                 blocksize = SPA_MINBLOCKSIZE;
 497         } else if (size > SPA_OLD_MAXBLOCKSIZE) {
 498                 ASSERT(0);
 499                 return (SET_ERROR(EFBIG));
 500         } else {
 501                 blocksize = P2ROUNDUP_TYPED(size, SPA_MINBLOCKSIZE, uint32_t);
 502         }
 503 
 504         error = dbuf_spill_set_blksz(hdl->sa_spill, blocksize, tx);
 505         ASSERT(error == 0);
 506         return (error);
 507 }
 508 
 509 static void
 510 sa_copy_data(sa_data_locator_t *func, void *datastart, void *target, int buflen)
 511 {
 512         if (func == NULL) {
 513                 bcopy(datastart, target, buflen);
 514         } else {
 515                 boolean_t start;
 516                 int bytes;
 517                 void *dataptr;
 518                 void *saptr = target;
 519                 uint32_t length;
 520 
 521                 start = B_TRUE;
 522                 bytes = 0;
 523                 while (bytes < buflen) {
 524                         func(&dataptr, &length, buflen, start, datastart);
 525                         bcopy(dataptr, saptr, length);
 526                         saptr = (void *)((caddr_t)saptr + length);
 527                         bytes += length;
 528                         start = B_FALSE;
 529                 }
 530         }
 531 }
 532 
 533 /*
 534  * Determine several different sizes
 535  * first the sa header size
 536  * the number of bytes to be stored
 537  * if spill would occur the index in the attribute array is returned
 538  *
 539  * the boolean will_spill will be set when spilling is necessary.  It
 540  * is only set when the buftype is SA_BONUS
 541  */
 542 static int
 543 sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
 544     dmu_buf_t *db, sa_buf_type_t buftype, int full_space, int *index,
 545     int *total, boolean_t *will_spill)
 546 {
 547         int var_size = 0;
 548         int i;
 549         int hdrsize;
 550         int extra_hdrsize;
 551 
 552         if (buftype == SA_BONUS && sa->sa_force_spill) {
 553                 *total = 0;
 554                 *index = 0;
 555                 *will_spill = B_TRUE;
 556                 return (0);
 557         }
 558 
 559         *index = -1;
 560         *total = 0;
 561         *will_spill = B_FALSE;
 562 
 563         extra_hdrsize = 0;
 564         hdrsize = (SA_BONUSTYPE_FROM_DB(db) == DMU_OT_ZNODE) ? 0 :
 565             sizeof (sa_hdr_phys_t);
 566 
 567         ASSERT(IS_P2ALIGNED(full_space, 8));
 568 
 569         for (i = 0; i != attr_count; i++) {
 570                 boolean_t is_var_sz;
 571 
 572                 *total = P2ROUNDUP(*total, 8);
 573                 *total += attr_desc[i].sa_length;
 574                 if (*will_spill)
 575                         continue;
 576 
 577                 is_var_sz = (SA_REGISTERED_LEN(sa, attr_desc[i].sa_attr) == 0);
 578                 if (is_var_sz) {
 579                         var_size++;
 580                 }
 581 
 582                 if (is_var_sz && var_size > 1) {
 583                         /*
 584                          * Don't worry that the spill block might overflow.
 585                          * It will be resized if needed in sa_build_layouts().
 586                          */
 587                         if (buftype == SA_SPILL ||
 588                             P2ROUNDUP(hdrsize + sizeof (uint16_t), 8) +
 589                             *total < full_space) {
 590                                 /*
 591                                  * Account for header space used by array of
 592                                  * optional sizes of variable-length attributes.
 593                                  * Record the extra header size in case this
 594                                  * increase needs to be reversed due to
 595                                  * spill-over.
 596                                  */
 597                                 hdrsize += sizeof (uint16_t);
 598                                 if (*index != -1)
 599                                         extra_hdrsize += sizeof (uint16_t);
 600                         } else {
 601                                 ASSERT(buftype == SA_BONUS);
 602                                 if (*index == -1)
 603                                         *index = i;
 604                                 *will_spill = B_TRUE;
 605                                 continue;
 606                         }
 607                 }
 608 
 609                 /*
 610                  * find index of where spill *could* occur.
 611                  * Then continue to count of remainder attribute
 612                  * space.  The sum is used later for sizing bonus
 613                  * and spill buffer.
 614                  */
 615                 if (buftype == SA_BONUS && *index == -1 &&
 616                     *total + P2ROUNDUP(hdrsize, 8) >
 617                     (full_space - sizeof (blkptr_t))) {
 618                         *index = i;
 619                 }
 620 
 621                 if (*total + P2ROUNDUP(hdrsize, 8) > full_space &&
 622                     buftype == SA_BONUS)
 623                         *will_spill = B_TRUE;
 624         }
 625 
 626         if (*will_spill)
 627                 hdrsize -= extra_hdrsize;
 628 
 629         hdrsize = P2ROUNDUP(hdrsize, 8);
 630         return (hdrsize);
 631 }
 632 
 633 #define BUF_SPACE_NEEDED(total, header) (total + header)
 634 
 635 /*
 636  * Find layout that corresponds to ordering of attributes
 637  * If not found a new layout number is created and added to
 638  * persistent layout tables.
 639  */
 640 static int
 641 sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
 642     dmu_tx_t *tx)
 643 {
 644         sa_os_t *sa = hdl->sa_os->os_sa;
 645         uint64_t hash;
 646         sa_buf_type_t buftype;
 647         sa_hdr_phys_t *sahdr;
 648         void *data_start;
 649         int buf_space;
 650         sa_attr_type_t *attrs, *attrs_start;
 651         int i, lot_count;
 652         int dnodesize;
 653         int hdrsize;
 654         int spillhdrsize = 0;
 655         int used;
 656         dmu_object_type_t bonustype;
 657         sa_lot_t *lot;
 658         int len_idx;
 659         int spill_used;
 660         int bonuslen;
 661         boolean_t spilling;
 662 
 663         dmu_buf_will_dirty(hdl->sa_bonus, tx);
 664         bonustype = SA_BONUSTYPE_FROM_DB(hdl->sa_bonus);
 665 
 666         dmu_object_dnsize_from_db(hdl->sa_bonus, &dnodesize);
 667         bonuslen = DN_BONUS_SIZE(dnodesize);
 668 
 669         /* first determine bonus header size and sum of all attributes */
 670         hdrsize = sa_find_sizes(sa, attr_desc, attr_count, hdl->sa_bonus,
 671             SA_BONUS, bonuslen, &i, &used, &spilling);
 672 
 673         if (used > SPA_OLD_MAXBLOCKSIZE)
 674                 return (SET_ERROR(EFBIG));
 675 
 676         VERIFY(0 == dmu_set_bonus(hdl->sa_bonus, spilling ?
 677             MIN(bonuslen - sizeof (blkptr_t), used + hdrsize) :
 678             used + hdrsize, tx));
 679 
 680         ASSERT((bonustype == DMU_OT_ZNODE && spilling == 0) ||
 681             bonustype == DMU_OT_SA);
 682 
 683         /* setup and size spill buffer when needed */
 684         if (spilling) {
 685                 boolean_t dummy;
 686 
 687                 if (hdl->sa_spill == NULL) {
 688                         VERIFY(dmu_spill_hold_by_bonus(hdl->sa_bonus, 0, NULL,
 689                             &hdl->sa_spill) == 0);
 690                 }
 691                 dmu_buf_will_dirty(hdl->sa_spill, tx);
 692 
 693                 spillhdrsize = sa_find_sizes(sa, &attr_desc[i],
 694                     attr_count - i, hdl->sa_spill, SA_SPILL,
 695                     hdl->sa_spill->db_size, &i, &spill_used, &dummy);
 696 
 697                 if (spill_used > SPA_OLD_MAXBLOCKSIZE)
 698                         return (SET_ERROR(EFBIG));
 699 
 700                 buf_space = hdl->sa_spill->db_size - spillhdrsize;
 701                 if (BUF_SPACE_NEEDED(spill_used, spillhdrsize) >
 702                     hdl->sa_spill->db_size)
 703                         VERIFY(0 == sa_resize_spill(hdl,
 704                             BUF_SPACE_NEEDED(spill_used, spillhdrsize), tx));
 705         }
 706 
 707         /* setup starting pointers to lay down data */
 708         data_start = (void *)((uintptr_t)hdl->sa_bonus->db_data + hdrsize);
 709         sahdr = (sa_hdr_phys_t *)hdl->sa_bonus->db_data;
 710         buftype = SA_BONUS;
 711 
 712         if (spilling)
 713                 buf_space = (sa->sa_force_spill) ?
 714                     0 : SA_BLKPTR_SPACE - hdrsize;
 715         else
 716                 buf_space = hdl->sa_bonus->db_size - hdrsize;
 717 
 718         attrs_start = attrs = kmem_alloc(sizeof (sa_attr_type_t) * attr_count,
 719             KM_SLEEP);
 720         lot_count = 0;
 721 
 722         for (i = 0, len_idx = 0, hash = -1ULL; i != attr_count; i++) {
 723                 uint16_t length;
 724 
 725                 ASSERT(IS_P2ALIGNED(data_start, 8));
 726                 ASSERT(IS_P2ALIGNED(buf_space, 8));
 727                 attrs[i] = attr_desc[i].sa_attr;
 728                 length = SA_REGISTERED_LEN(sa, attrs[i]);
 729                 if (length == 0)
 730                         length = attr_desc[i].sa_length;
 731 
 732                 if (buf_space < length) {  /* switch to spill buffer */
 733                         VERIFY(spilling);
 734                         VERIFY(bonustype == DMU_OT_SA);
 735                         if (buftype == SA_BONUS && !sa->sa_force_spill) {
 736                                 sa_find_layout(hdl->sa_os, hash, attrs_start,
 737                                     lot_count, tx, &lot);
 738                                 SA_SET_HDR(sahdr, lot->lot_num, hdrsize);
 739                         }
 740 
 741                         buftype = SA_SPILL;
 742                         hash = -1ULL;
 743                         len_idx = 0;
 744 
 745                         sahdr = (sa_hdr_phys_t *)hdl->sa_spill->db_data;
 746                         sahdr->sa_magic = SA_MAGIC;
 747                         data_start = (void *)((uintptr_t)sahdr +
 748                             spillhdrsize);
 749                         attrs_start = &attrs[i];
 750                         buf_space = hdl->sa_spill->db_size - spillhdrsize;
 751                         lot_count = 0;
 752                 }
 753                 hash ^= SA_ATTR_HASH(attrs[i]);
 754                 attr_desc[i].sa_addr = data_start;
 755                 attr_desc[i].sa_size = length;
 756                 SA_COPY_DATA(attr_desc[i].sa_data_func, attr_desc[i].sa_data,
 757                     data_start, length);
 758                 if (sa->sa_attr_table[attrs[i]].sa_length == 0) {
 759                         sahdr->sa_lengths[len_idx++] = length;
 760                 }
 761                 data_start = (void *)P2ROUNDUP(((uintptr_t)data_start +
 762                     length), 8);
 763                 buf_space -= P2ROUNDUP(length, 8);
 764                 lot_count++;
 765         }
 766 
 767         sa_find_layout(hdl->sa_os, hash, attrs_start, lot_count, tx, &lot);
 768 
 769         /*
 770          * Verify that old znodes always have layout number 0.
 771          * Must be DMU_OT_SA for arbitrary layouts
 772          */
 773         VERIFY((bonustype == DMU_OT_ZNODE && lot->lot_num == 0) ||
 774             (bonustype == DMU_OT_SA && lot->lot_num > 1));
 775 
 776         if (bonustype == DMU_OT_SA) {
 777                 SA_SET_HDR(sahdr, lot->lot_num,
 778                     buftype == SA_BONUS ? hdrsize : spillhdrsize);
 779         }
 780 
 781         kmem_free(attrs, sizeof (sa_attr_type_t) * attr_count);
 782         if (hdl->sa_bonus_tab) {
 783                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_bonus_tab);
 784                 hdl->sa_bonus_tab = NULL;
 785         }
 786         if (!sa->sa_force_spill)
 787                 VERIFY(0 == sa_build_index(hdl, SA_BONUS));
 788         if (hdl->sa_spill) {
 789                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_spill_tab);
 790                 if (!spilling) {
 791                         /*
 792                          * remove spill block that is no longer needed.
 793                          */
 794                         dmu_buf_rele(hdl->sa_spill, NULL);
 795                         hdl->sa_spill = NULL;
 796                         hdl->sa_spill_tab = NULL;
 797                         VERIFY(0 == dmu_rm_spill(hdl->sa_os,
 798                             sa_handle_object(hdl), tx));
 799                 } else {
 800                         VERIFY(0 == sa_build_index(hdl, SA_SPILL));
 801                 }
 802         }
 803 
 804         return (0);
 805 }
 806 
 807 static void
 808 sa_free_attr_table(sa_os_t *sa)
 809 {
 810         int i;
 811 
 812         if (sa->sa_attr_table == NULL)
 813                 return;
 814 
 815         for (i = 0; i != sa->sa_num_attrs; i++) {
 816                 if (sa->sa_attr_table[i].sa_name)
 817                         kmem_free(sa->sa_attr_table[i].sa_name,
 818                             strlen(sa->sa_attr_table[i].sa_name) + 1);
 819         }
 820 
 821         kmem_free(sa->sa_attr_table,
 822             sizeof (sa_attr_table_t) * sa->sa_num_attrs);
 823 
 824         sa->sa_attr_table = NULL;
 825 }
 826 
 827 static int
 828 sa_attr_table_setup(objset_t *os, sa_attr_reg_t *reg_attrs, int count)
 829 {
 830         sa_os_t *sa = os->os_sa;
 831         uint64_t sa_attr_count = 0;
 832         uint64_t sa_reg_count = 0;
 833         int error = 0;
 834         uint64_t attr_value;
 835         sa_attr_table_t *tb;
 836         zap_cursor_t zc;
 837         zap_attribute_t za;
 838         int registered_count = 0;
 839         int i;
 840         dmu_objset_type_t ostype = dmu_objset_type(os);
 841 
 842         sa->sa_user_table =
 843             kmem_zalloc(count * sizeof (sa_attr_type_t), KM_SLEEP);
 844         sa->sa_user_table_sz = count * sizeof (sa_attr_type_t);
 845 
 846         if (sa->sa_reg_attr_obj != 0) {
 847                 error = zap_count(os, sa->sa_reg_attr_obj,
 848                     &sa_attr_count);
 849 
 850                 /*
 851                  * Make sure we retrieved a count and that it isn't zero
 852                  */
 853                 if (error || (error == 0 && sa_attr_count == 0)) {
 854                         if (error == 0)
 855                                 error = SET_ERROR(EINVAL);
 856                         goto bail;
 857                 }
 858                 sa_reg_count = sa_attr_count;
 859         }
 860 
 861         if (ostype == DMU_OST_ZFS && sa_attr_count == 0)
 862                 sa_attr_count += sa_legacy_attr_count;
 863 
 864         /* Allocate attribute numbers for attributes that aren't registered */
 865         for (i = 0; i != count; i++) {
 866                 boolean_t found = B_FALSE;
 867                 int j;
 868 
 869                 if (ostype == DMU_OST_ZFS) {
 870                         for (j = 0; j != sa_legacy_attr_count; j++) {
 871                                 if (strcmp(reg_attrs[i].sa_name,
 872                                     sa_legacy_attrs[j].sa_name) == 0) {
 873                                         sa->sa_user_table[i] =
 874                                             sa_legacy_attrs[j].sa_attr;
 875                                         found = B_TRUE;
 876                                 }
 877                         }
 878                 }
 879                 if (found)
 880                         continue;
 881 
 882                 if (sa->sa_reg_attr_obj)
 883                         error = zap_lookup(os, sa->sa_reg_attr_obj,
 884                             reg_attrs[i].sa_name, 8, 1, &attr_value);
 885                 else
 886                         error = SET_ERROR(ENOENT);
 887                 switch (error) {
 888                 case ENOENT:
 889                         sa->sa_user_table[i] = (sa_attr_type_t)sa_attr_count;
 890                         sa_attr_count++;
 891                         break;
 892                 case 0:
 893                         sa->sa_user_table[i] = ATTR_NUM(attr_value);
 894                         break;
 895                 default:
 896                         goto bail;
 897                 }
 898         }
 899 
 900         sa->sa_num_attrs = sa_attr_count;
 901         tb = sa->sa_attr_table =
 902             kmem_zalloc(sizeof (sa_attr_table_t) * sa_attr_count, KM_SLEEP);
 903 
 904         /*
 905          * Attribute table is constructed from requested attribute list,
 906          * previously foreign registered attributes, and also the legacy
 907          * ZPL set of attributes.
 908          */
 909 
 910         if (sa->sa_reg_attr_obj) {
 911                 for (zap_cursor_init(&zc, os, sa->sa_reg_attr_obj);
 912                     (error = zap_cursor_retrieve(&zc, &za)) == 0;
 913                     zap_cursor_advance(&zc)) {
 914                         uint64_t value;
 915                         value  = za.za_first_integer;
 916 
 917                         registered_count++;
 918                         tb[ATTR_NUM(value)].sa_attr = ATTR_NUM(value);
 919                         tb[ATTR_NUM(value)].sa_length = ATTR_LENGTH(value);
 920                         tb[ATTR_NUM(value)].sa_byteswap = ATTR_BSWAP(value);
 921                         tb[ATTR_NUM(value)].sa_registered = B_TRUE;
 922 
 923                         if (tb[ATTR_NUM(value)].sa_name) {
 924                                 continue;
 925                         }
 926                         tb[ATTR_NUM(value)].sa_name =
 927                             kmem_zalloc(strlen(za.za_name) +1, KM_SLEEP);
 928                         (void) strlcpy(tb[ATTR_NUM(value)].sa_name, za.za_name,
 929                             strlen(za.za_name) +1);
 930                 }
 931                 zap_cursor_fini(&zc);
 932                 /*
 933                  * Make sure we processed the correct number of registered
 934                  * attributes
 935                  */
 936                 if (registered_count != sa_reg_count) {
 937                         ASSERT(error != 0);
 938                         goto bail;
 939                 }
 940 
 941         }
 942 
 943         if (ostype == DMU_OST_ZFS) {
 944                 for (i = 0; i != sa_legacy_attr_count; i++) {
 945                         if (tb[i].sa_name)
 946                                 continue;
 947                         tb[i].sa_attr = sa_legacy_attrs[i].sa_attr;
 948                         tb[i].sa_length = sa_legacy_attrs[i].sa_length;
 949                         tb[i].sa_byteswap = sa_legacy_attrs[i].sa_byteswap;
 950                         tb[i].sa_registered = B_FALSE;
 951                         tb[i].sa_name =
 952                             kmem_zalloc(strlen(sa_legacy_attrs[i].sa_name) +1,
 953                             KM_SLEEP);
 954                         (void) strlcpy(tb[i].sa_name,
 955                             sa_legacy_attrs[i].sa_name,
 956                             strlen(sa_legacy_attrs[i].sa_name) + 1);
 957                 }
 958         }
 959 
 960         for (i = 0; i != count; i++) {
 961                 sa_attr_type_t attr_id;
 962 
 963                 attr_id = sa->sa_user_table[i];
 964                 if (tb[attr_id].sa_name)
 965                         continue;
 966 
 967                 tb[attr_id].sa_length = reg_attrs[i].sa_length;
 968                 tb[attr_id].sa_byteswap = reg_attrs[i].sa_byteswap;
 969                 tb[attr_id].sa_attr = attr_id;
 970                 tb[attr_id].sa_name =
 971                     kmem_zalloc(strlen(reg_attrs[i].sa_name) + 1, KM_SLEEP);
 972                 (void) strlcpy(tb[attr_id].sa_name, reg_attrs[i].sa_name,
 973                     strlen(reg_attrs[i].sa_name) + 1);
 974         }
 975 
 976         sa->sa_need_attr_registration =
 977             (sa_attr_count != registered_count);
 978 
 979         return (0);
 980 bail:
 981         kmem_free(sa->sa_user_table, count * sizeof (sa_attr_type_t));
 982         sa->sa_user_table = NULL;
 983         sa_free_attr_table(sa);
 984         return ((error != 0) ? error : EINVAL);
 985 }
 986 
 987 int
 988 sa_setup(objset_t *os, uint64_t sa_obj, sa_attr_reg_t *reg_attrs, int count,
 989     sa_attr_type_t **user_table)
 990 {
 991         zap_cursor_t zc;
 992         zap_attribute_t za;
 993         sa_os_t *sa;
 994         dmu_objset_type_t ostype = dmu_objset_type(os);
 995         sa_attr_type_t *tb;
 996         int error;
 997 
 998         mutex_enter(&os->os_user_ptr_lock);
 999         if (os->os_sa) {
1000                 mutex_enter(&os->os_sa->sa_lock);
1001                 mutex_exit(&os->os_user_ptr_lock);
1002                 tb = os->os_sa->sa_user_table;
1003                 mutex_exit(&os->os_sa->sa_lock);
1004                 *user_table = tb;
1005                 return (0);
1006         }
1007 
1008         sa = kmem_zalloc(sizeof (sa_os_t), KM_SLEEP);
1009         mutex_init(&sa->sa_lock, NULL, MUTEX_DEFAULT, NULL);
1010         sa->sa_master_obj = sa_obj;
1011 
1012         os->os_sa = sa;
1013         mutex_enter(&sa->sa_lock);
1014         mutex_exit(&os->os_user_ptr_lock);
1015         avl_create(&sa->sa_layout_num_tree, layout_num_compare,
1016             sizeof (sa_lot_t), offsetof(sa_lot_t, lot_num_node));
1017         avl_create(&sa->sa_layout_hash_tree, layout_hash_compare,
1018             sizeof (sa_lot_t), offsetof(sa_lot_t, lot_hash_node));
1019 
1020         if (sa_obj) {
1021                 error = zap_lookup(os, sa_obj, SA_LAYOUTS,
1022                     8, 1, &sa->sa_layout_attr_obj);
1023                 if (error != 0 && error != ENOENT)
1024                         goto fail;
1025                 error = zap_lookup(os, sa_obj, SA_REGISTRY,
1026                     8, 1, &sa->sa_reg_attr_obj);
1027                 if (error != 0 && error != ENOENT)
1028                         goto fail;
1029         }
1030 
1031         if ((error = sa_attr_table_setup(os, reg_attrs, count)) != 0)
1032                 goto fail;
1033 
1034         if (sa->sa_layout_attr_obj != 0) {
1035                 uint64_t layout_count;
1036 
1037                 error = zap_count(os, sa->sa_layout_attr_obj,
1038                     &layout_count);
1039 
1040                 /*
1041                  * Layout number count should be > 0
1042                  */
1043                 if (error || (error == 0 && layout_count == 0)) {
1044                         if (error == 0)
1045                                 error = SET_ERROR(EINVAL);
1046                         goto fail;
1047                 }
1048 
1049                 for (zap_cursor_init(&zc, os, sa->sa_layout_attr_obj);
1050                     (error = zap_cursor_retrieve(&zc, &za)) == 0;
1051                     zap_cursor_advance(&zc)) {
1052                         sa_attr_type_t *lot_attrs;
1053                         uint64_t lot_num;
1054 
1055                         lot_attrs = kmem_zalloc(sizeof (sa_attr_type_t) *
1056                             za.za_num_integers, KM_SLEEP);
1057 
1058                         if ((error = (zap_lookup(os, sa->sa_layout_attr_obj,
1059                             za.za_name, 2, za.za_num_integers,
1060                             lot_attrs))) != 0) {
1061                                 kmem_free(lot_attrs, sizeof (sa_attr_type_t) *
1062                                     za.za_num_integers);
1063                                 break;
1064                         }
1065                         VERIFY(ddi_strtoull(za.za_name, NULL, 10,
1066                             (unsigned long long *)&lot_num) == 0);
1067 
1068                         (void) sa_add_layout_entry(os, lot_attrs,
1069                             za.za_num_integers, lot_num,
1070                             sa_layout_info_hash(lot_attrs,
1071                             za.za_num_integers), B_FALSE, NULL);
1072                         kmem_free(lot_attrs, sizeof (sa_attr_type_t) *
1073                             za.za_num_integers);
1074                 }
1075                 zap_cursor_fini(&zc);
1076 
1077                 /*
1078                  * Make sure layout count matches number of entries added
1079                  * to AVL tree
1080                  */
1081                 if (avl_numnodes(&sa->sa_layout_num_tree) != layout_count) {
1082                         ASSERT(error != 0);
1083                         goto fail;
1084                 }
1085         }
1086 
1087         /* Add special layout number for old ZNODES */
1088         if (ostype == DMU_OST_ZFS) {
1089                 (void) sa_add_layout_entry(os, sa_legacy_zpl_layout,
1090                     sa_legacy_attr_count, 0,
1091                     sa_layout_info_hash(sa_legacy_zpl_layout,
1092                     sa_legacy_attr_count), B_FALSE, NULL);
1093 
1094                 (void) sa_add_layout_entry(os, sa_dummy_zpl_layout, 0, 1,
1095                     0, B_FALSE, NULL);
1096         }
1097         *user_table = os->os_sa->sa_user_table;
1098         mutex_exit(&sa->sa_lock);
1099         return (0);
1100 fail:
1101         os->os_sa = NULL;
1102         sa_free_attr_table(sa);
1103         if (sa->sa_user_table)
1104                 kmem_free(sa->sa_user_table, sa->sa_user_table_sz);
1105         mutex_exit(&sa->sa_lock);
1106         avl_destroy(&sa->sa_layout_hash_tree);
1107         avl_destroy(&sa->sa_layout_num_tree);
1108         mutex_destroy(&sa->sa_lock);
1109         kmem_free(sa, sizeof (sa_os_t));
1110         return ((error == ECKSUM) ? EIO : error);
1111 }
1112 
1113 void
1114 sa_tear_down(objset_t *os)
1115 {
1116         sa_os_t *sa = os->os_sa;
1117         sa_lot_t *layout;
1118         void *cookie;
1119 
1120         kmem_free(sa->sa_user_table, sa->sa_user_table_sz);
1121 
1122         /* Free up attr table */
1123 
1124         sa_free_attr_table(sa);
1125 
1126         cookie = NULL;
1127         while (layout = avl_destroy_nodes(&sa->sa_layout_hash_tree, &cookie)) {
1128                 sa_idx_tab_t *tab;
1129                 while (tab = list_head(&layout->lot_idx_tab)) {
1130                         ASSERT(zfs_refcount_count(&tab->sa_refcount));
1131                         sa_idx_tab_rele(os, tab);
1132                 }
1133         }
1134 
1135         cookie = NULL;
1136         while (layout = avl_destroy_nodes(&sa->sa_layout_num_tree, &cookie)) {
1137                 kmem_free(layout->lot_attrs,
1138                     sizeof (sa_attr_type_t) * layout->lot_attr_count);
1139                 kmem_free(layout, sizeof (sa_lot_t));
1140         }
1141 
1142         avl_destroy(&sa->sa_layout_hash_tree);
1143         avl_destroy(&sa->sa_layout_num_tree);
1144         mutex_destroy(&sa->sa_lock);
1145 
1146         kmem_free(sa, sizeof (sa_os_t));
1147         os->os_sa = NULL;
1148 }
1149 
1150 void
1151 sa_build_idx_tab(void *hdr, void *attr_addr, sa_attr_type_t attr,
1152     uint16_t length, int length_idx, boolean_t var_length, void *userp)
1153 {
1154         sa_idx_tab_t *idx_tab = userp;
1155 
1156         if (var_length) {
1157                 ASSERT(idx_tab->sa_variable_lengths);
1158                 idx_tab->sa_variable_lengths[length_idx] = length;
1159         }
1160         TOC_ATTR_ENCODE(idx_tab->sa_idx_tab[attr], length_idx,
1161             (uint32_t)((uintptr_t)attr_addr - (uintptr_t)hdr));
1162 }
1163 
1164 static void
1165 sa_attr_iter(objset_t *os, sa_hdr_phys_t *hdr, dmu_object_type_t type,
1166     sa_iterfunc_t func, sa_lot_t *tab, void *userp)
1167 {
1168         void *data_start;
1169         sa_lot_t *tb = tab;
1170         sa_lot_t search;
1171         avl_index_t loc;
1172         sa_os_t *sa = os->os_sa;
1173         int i;
1174         uint16_t *length_start = NULL;
1175         uint8_t length_idx = 0;
1176 
1177         if (tab == NULL) {
1178                 search.lot_num = SA_LAYOUT_NUM(hdr, type);
1179                 tb = avl_find(&sa->sa_layout_num_tree, &search, &loc);
1180                 ASSERT(tb);
1181         }
1182 
1183         if (IS_SA_BONUSTYPE(type)) {
1184                 data_start = (void *)P2ROUNDUP(((uintptr_t)hdr +
1185                     offsetof(sa_hdr_phys_t, sa_lengths) +
1186                     (sizeof (uint16_t) * tb->lot_var_sizes)), 8);
1187                 length_start = hdr->sa_lengths;
1188         } else {
1189                 data_start = hdr;
1190         }
1191 
1192         for (i = 0; i != tb->lot_attr_count; i++) {
1193                 int attr_length, reg_length;
1194                 uint8_t idx_len;
1195 
1196                 reg_length = sa->sa_attr_table[tb->lot_attrs[i]].sa_length;
1197                 if (reg_length) {
1198                         attr_length = reg_length;
1199                         idx_len = 0;
1200                 } else {
1201                         attr_length = length_start[length_idx];
1202                         idx_len = length_idx++;
1203                 }
1204 
1205                 func(hdr, data_start, tb->lot_attrs[i], attr_length,
1206                     idx_len, reg_length == 0 ? B_TRUE : B_FALSE, userp);
1207 
1208                 data_start = (void *)P2ROUNDUP(((uintptr_t)data_start +
1209                     attr_length), 8);
1210         }
1211 }
1212 
1213 /*ARGSUSED*/
1214 void
1215 sa_byteswap_cb(void *hdr, void *attr_addr, sa_attr_type_t attr,
1216     uint16_t length, int length_idx, boolean_t variable_length, void *userp)
1217 {
1218         sa_handle_t *hdl = userp;
1219         sa_os_t *sa = hdl->sa_os->os_sa;
1220 
1221         sa_bswap_table[sa->sa_attr_table[attr].sa_byteswap](attr_addr, length);
1222 }
1223 
1224 void
1225 sa_byteswap(sa_handle_t *hdl, sa_buf_type_t buftype)
1226 {
1227         sa_hdr_phys_t *sa_hdr_phys = SA_GET_HDR(hdl, buftype);
1228         dmu_buf_impl_t *db;
1229         sa_os_t *sa = hdl->sa_os->os_sa;
1230         int num_lengths = 1;
1231         int i;
1232 
1233         ASSERT(MUTEX_HELD(&sa->sa_lock));
1234         if (sa_hdr_phys->sa_magic == SA_MAGIC)
1235                 return;
1236 
1237         db = SA_GET_DB(hdl, buftype);
1238 
1239         if (buftype == SA_SPILL) {
1240                 arc_release(db->db_buf, NULL);
1241                 arc_buf_thaw(db->db_buf);
1242         }
1243 
1244         sa_hdr_phys->sa_magic = BSWAP_32(sa_hdr_phys->sa_magic);
1245         sa_hdr_phys->sa_layout_info = BSWAP_16(sa_hdr_phys->sa_layout_info);
1246 
1247         /*
1248          * Determine number of variable lenghts in header
1249          * The standard 8 byte header has one for free and a
1250          * 16 byte header would have 4 + 1;
1251          */
1252         if (SA_HDR_SIZE(sa_hdr_phys) > 8)
1253                 num_lengths += (SA_HDR_SIZE(sa_hdr_phys) - 8) >> 1;
1254         for (i = 0; i != num_lengths; i++)
1255                 sa_hdr_phys->sa_lengths[i] =
1256                     BSWAP_16(sa_hdr_phys->sa_lengths[i]);
1257 
1258         sa_attr_iter(hdl->sa_os, sa_hdr_phys, DMU_OT_SA,
1259             sa_byteswap_cb, NULL, hdl);
1260 
1261         if (buftype == SA_SPILL)
1262                 arc_buf_freeze(((dmu_buf_impl_t *)hdl->sa_spill)->db_buf);
1263 }
1264 
1265 static int
1266 sa_build_index(sa_handle_t *hdl, sa_buf_type_t buftype)
1267 {
1268         sa_hdr_phys_t *sa_hdr_phys;
1269         dmu_buf_impl_t *db = SA_GET_DB(hdl, buftype);
1270         dmu_object_type_t bonustype = SA_BONUSTYPE_FROM_DB(db);
1271         sa_os_t *sa = hdl->sa_os->os_sa;
1272         sa_idx_tab_t *idx_tab;
1273 
1274         sa_hdr_phys = SA_GET_HDR(hdl, buftype);
1275 
1276         mutex_enter(&sa->sa_lock);
1277 
1278         /* Do we need to byteswap? */
1279 
1280         /* only check if not old znode */
1281         if (IS_SA_BONUSTYPE(bonustype) && sa_hdr_phys->sa_magic != SA_MAGIC &&
1282             sa_hdr_phys->sa_magic != 0) {
1283                 VERIFY(BSWAP_32(sa_hdr_phys->sa_magic) == SA_MAGIC);
1284                 sa_byteswap(hdl, buftype);
1285         }
1286 
1287         idx_tab = sa_find_idx_tab(hdl->sa_os, bonustype, sa_hdr_phys);
1288 
1289         if (buftype == SA_BONUS)
1290                 hdl->sa_bonus_tab = idx_tab;
1291         else
1292                 hdl->sa_spill_tab = idx_tab;
1293 
1294         mutex_exit(&sa->sa_lock);
1295         return (0);
1296 }
1297 
1298 /*ARGSUSED*/
1299 static void
1300 sa_evict_sync(void *dbu)
1301 {
1302         panic("evicting sa dbuf\n");
1303 }
1304 
1305 static void
1306 sa_idx_tab_rele(objset_t *os, void *arg)
1307 {
1308         sa_os_t *sa = os->os_sa;
1309         sa_idx_tab_t *idx_tab = arg;
1310 
1311         if (idx_tab == NULL)
1312                 return;
1313 
1314         mutex_enter(&sa->sa_lock);
1315         if (zfs_refcount_remove(&idx_tab->sa_refcount, NULL) == 0) {
1316                 list_remove(&idx_tab->sa_layout->lot_idx_tab, idx_tab);
1317                 if (idx_tab->sa_variable_lengths)
1318                         kmem_free(idx_tab->sa_variable_lengths,
1319                             sizeof (uint16_t) *
1320                             idx_tab->sa_layout->lot_var_sizes);
1321                 zfs_refcount_destroy(&idx_tab->sa_refcount);
1322                 kmem_free(idx_tab->sa_idx_tab,
1323                     sizeof (uint32_t) * sa->sa_num_attrs);
1324                 kmem_free(idx_tab, sizeof (sa_idx_tab_t));
1325         }
1326         mutex_exit(&sa->sa_lock);
1327 }
1328 
1329 static void
1330 sa_idx_tab_hold(objset_t *os, sa_idx_tab_t *idx_tab)
1331 {
1332         sa_os_t *sa = os->os_sa;
1333 
1334         ASSERT(MUTEX_HELD(&sa->sa_lock));
1335         (void) zfs_refcount_add(&idx_tab->sa_refcount, NULL);
1336 }
1337 
1338 void
1339 sa_handle_destroy(sa_handle_t *hdl)
1340 {
1341         dmu_buf_t *db = hdl->sa_bonus;
1342 
1343         mutex_enter(&hdl->sa_lock);
1344         (void) dmu_buf_remove_user(db, &hdl->sa_dbu);
1345 
1346         if (hdl->sa_bonus_tab)
1347                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_bonus_tab);
1348 
1349         if (hdl->sa_spill_tab)
1350                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_spill_tab);
1351 
1352         dmu_buf_rele(hdl->sa_bonus, NULL);
1353 
1354         if (hdl->sa_spill)
1355                 dmu_buf_rele((dmu_buf_t *)hdl->sa_spill, NULL);
1356         mutex_exit(&hdl->sa_lock);
1357 
1358         kmem_cache_free(sa_cache, hdl);
1359 }
1360 
1361 int
1362 sa_handle_get_from_db(objset_t *os, dmu_buf_t *db, void *userp,
1363     sa_handle_type_t hdl_type, sa_handle_t **handlepp)
1364 {
1365         int error = 0;
1366         dmu_object_info_t doi;
1367         sa_handle_t *handle = NULL;
1368 
1369 #ifdef ZFS_DEBUG
1370         dmu_object_info_from_db(db, &doi);
1371         ASSERT(doi.doi_bonus_type == DMU_OT_SA ||
1372             doi.doi_bonus_type == DMU_OT_ZNODE);
1373 #endif
1374         /* find handle, if it exists */
1375         /* if one doesn't exist then create a new one, and initialize it */
1376 
1377         if (hdl_type == SA_HDL_SHARED)
1378                 handle = dmu_buf_get_user(db);
1379 
1380         if (handle == NULL) {
1381                 sa_handle_t *winner = NULL;
1382 
1383                 handle = kmem_cache_alloc(sa_cache, KM_SLEEP);
1384                 handle->sa_dbu.dbu_evict_func_sync = NULL;
1385                 handle->sa_dbu.dbu_evict_func_async = NULL;
1386                 handle->sa_userp = userp;
1387                 handle->sa_bonus = db;
1388                 handle->sa_os = os;
1389                 handle->sa_spill = NULL;
1390                 handle->sa_bonus_tab = NULL;
1391                 handle->sa_spill_tab = NULL;
1392 
1393                 error = sa_build_index(handle, SA_BONUS);
1394 
1395                 if (hdl_type == SA_HDL_SHARED) {
1396                         dmu_buf_init_user(&handle->sa_dbu, sa_evict_sync, NULL,
1397                             NULL);
1398                         winner = dmu_buf_set_user_ie(db, &handle->sa_dbu);
1399                 }
1400 
1401                 if (winner != NULL) {
1402                         kmem_cache_free(sa_cache, handle);
1403                         handle = winner;
1404                 }
1405         }
1406         *handlepp = handle;
1407 
1408         return (error);
1409 }
1410 
1411 int
1412 sa_handle_get(objset_t *objset, uint64_t objid, void *userp,
1413     sa_handle_type_t hdl_type, sa_handle_t **handlepp)
1414 {
1415         dmu_buf_t *db;
1416         int error;
1417 
1418         if (error = dmu_bonus_hold(objset, objid, NULL, &db))
1419                 return (error);
1420 
1421         return (sa_handle_get_from_db(objset, db, userp, hdl_type,
1422             handlepp));
1423 }
1424 
1425 int
1426 sa_buf_hold(objset_t *objset, uint64_t obj_num, void *tag, dmu_buf_t **db)
1427 {
1428         return (dmu_bonus_hold(objset, obj_num, tag, db));
1429 }
1430 
1431 void
1432 sa_buf_rele(dmu_buf_t *db, void *tag)
1433 {
1434         dmu_buf_rele(db, tag);
1435 }
1436 
1437 int
1438 sa_lookup_impl(sa_handle_t *hdl, sa_bulk_attr_t *bulk, int count)
1439 {
1440         ASSERT(hdl);
1441         ASSERT(MUTEX_HELD(&hdl->sa_lock));
1442         return (sa_attr_op(hdl, bulk, count, SA_LOOKUP, NULL));
1443 }
1444 
1445 static int
1446 sa_lookup_locked(sa_handle_t *hdl, sa_attr_type_t attr, void *buf,
1447     uint32_t buflen)
1448 {
1449         int error;
1450         sa_bulk_attr_t bulk;
1451 
1452         bulk.sa_attr = attr;
1453         bulk.sa_data = buf;
1454         bulk.sa_length = buflen;
1455         bulk.sa_data_func = NULL;
1456 
1457         ASSERT(hdl);
1458         error = sa_lookup_impl(hdl, &bulk, 1);
1459         return (error);
1460 }
1461 
1462 int
1463 sa_lookup(sa_handle_t *hdl, sa_attr_type_t attr, void *buf, uint32_t buflen)
1464 {
1465         int error;
1466 
1467         mutex_enter(&hdl->sa_lock);
1468         error = sa_lookup_locked(hdl, attr, buf, buflen);
1469         mutex_exit(&hdl->sa_lock);
1470 
1471         return (error);
1472 }
1473 
1474 #ifdef _KERNEL
1475 int
1476 sa_lookup_uio(sa_handle_t *hdl, sa_attr_type_t attr, uio_t *uio)
1477 {
1478         int error;
1479         sa_bulk_attr_t bulk;
1480 
1481         bulk.sa_data = NULL;
1482         bulk.sa_attr = attr;
1483         bulk.sa_data_func = NULL;
1484 
1485         ASSERT(hdl);
1486 
1487         mutex_enter(&hdl->sa_lock);
1488         if ((error = sa_attr_op(hdl, &bulk, 1, SA_LOOKUP, NULL)) == 0) {
1489                 error = uiomove((void *)bulk.sa_addr, MIN(bulk.sa_size,
1490                     uio->uio_resid), UIO_READ, uio);
1491         }
1492         mutex_exit(&hdl->sa_lock);
1493         return (error);
1494 
1495 }
1496 
1497 /*
1498  * For the existing object that is upgraded from old system, its ondisk layout
1499  * has no slot for the project ID attribute. But quota accounting logic needs
1500  * to access related slots by offset directly. So we need to adjust these old
1501  * objects' layout to make the project ID to some unified and fixed offset.
1502  */
1503 int
1504 sa_add_projid(sa_handle_t *hdl, dmu_tx_t *tx, uint64_t projid)
1505 {
1506         znode_t *zp = sa_get_userdata(hdl);
1507         dmu_buf_t *db = sa_get_db(hdl);
1508         zfsvfs_t *zfsvfs = zp->z_zfsvfs;
1509         int count = 0, err = 0;
1510         sa_bulk_attr_t *bulk, *attrs;
1511         zfs_acl_locator_cb_t locate = { 0 };
1512         uint64_t uid, gid, mode, rdev, xattr = 0, parent, gen, links;
1513         uint64_t crtime[2], mtime[2], ctime[2], atime[2];
1514         zfs_acl_phys_t znode_acl = { 0 };
1515         char scanstamp[AV_SCANSTAMP_SZ];
1516 
1517         if (zp->z_acl_cached == NULL) {
1518                 zfs_acl_t *aclp;
1519 
1520                 mutex_enter(&zp->z_acl_lock);
1521                 err = zfs_acl_node_read(zp, B_FALSE, &aclp, B_FALSE);
1522                 mutex_exit(&zp->z_acl_lock);
1523                 if (err != 0 && err != ENOENT)
1524                         return (err);
1525         }
1526 
1527         bulk = kmem_zalloc(sizeof (sa_bulk_attr_t) * ZPL_END, KM_SLEEP);
1528         attrs = kmem_zalloc(sizeof (sa_bulk_attr_t) * ZPL_END, KM_SLEEP);
1529         mutex_enter(&hdl->sa_lock);
1530         mutex_enter(&zp->z_lock);
1531 
1532         err = sa_lookup_locked(hdl, SA_ZPL_PROJID(zfsvfs), &projid,
1533             sizeof (uint64_t));
1534         if (unlikely(err == 0))
1535                 /* Someone has added project ID attr by race. */
1536                 err = EEXIST;
1537         if (err != ENOENT)
1538                 goto out;
1539 
1540         /* First do a bulk query of the attributes that aren't cached */
1541         if (zp->z_is_sa) {
1542                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs), NULL,
1543                     &mode, 8);
1544                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GEN(zfsvfs), NULL,
1545                     &gen, 8);
1546                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL,
1547                     &uid, 8);
1548                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs), NULL,
1549                     &gid, 8);
1550                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL,
1551                     &parent, 8);
1552                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ATIME(zfsvfs), NULL,
1553                     &atime, 16);
1554                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
1555                     &mtime, 16);
1556                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
1557                     &ctime, 16);
1558                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CRTIME(zfsvfs), NULL,
1559                     &crtime, 16);
1560                 if (S_ISBLK(zp->z_mode) || S_ISCHR(zp->z_mode))
1561                         SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_RDEV(zfsvfs), NULL,
1562                             &rdev, 8);
1563         } else {
1564                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ATIME(zfsvfs), NULL,
1565                     &atime, 16);
1566                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
1567                     &mtime, 16);
1568                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
1569                     &ctime, 16);
1570                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CRTIME(zfsvfs), NULL,
1571                     &crtime, 16);
1572                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GEN(zfsvfs), NULL,
1573                     &gen, 8);
1574                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs), NULL,
1575                     &mode, 8);
1576                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL,
1577                     &parent, 8);
1578                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_XATTR(zfsvfs), NULL,
1579                     &xattr, 8);
1580                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_RDEV(zfsvfs), NULL,
1581                     &rdev, 8);
1582                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL,
1583                     &uid, 8);
1584                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs), NULL,
1585                     &gid, 8);
1586                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ZNODE_ACL(zfsvfs), NULL,
1587                     &znode_acl, 88);
1588         }
1589         err = sa_bulk_lookup_locked(hdl, bulk, count);
1590         if (err != 0)
1591                 goto out;
1592 
1593         err = sa_lookup_locked(hdl, SA_ZPL_XATTR(zfsvfs), &xattr, 8);
1594         if (err != 0 && err != ENOENT)
1595                 goto out;
1596 
1597         zp->z_projid = projid;
1598         zp->z_pflags |= ZFS_PROJID;
1599         links = zp->z_links;
1600         count = 0;
1601         err = 0;
1602 
1603         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_MODE(zfsvfs), NULL, &mode, 8);
1604         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_SIZE(zfsvfs), NULL,
1605             &zp->z_size, 8);
1606         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_GEN(zfsvfs), NULL, &gen, 8);
1607         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_UID(zfsvfs), NULL, &uid, 8);
1608         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_GID(zfsvfs), NULL, &gid, 8);
1609         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_PARENT(zfsvfs), NULL, &parent, 8);
1610         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_FLAGS(zfsvfs), NULL,
1611             &zp->z_pflags, 8);
1612         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_ATIME(zfsvfs), NULL, &atime, 16);
1613         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_MTIME(zfsvfs), NULL, &mtime, 16);
1614         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_CTIME(zfsvfs), NULL, &ctime, 16);
1615         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_CRTIME(zfsvfs), NULL,
1616             &crtime, 16);
1617         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_LINKS(zfsvfs), NULL, &links, 8);
1618         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_PROJID(zfsvfs), NULL, &projid, 8);
1619 
1620         if (S_ISBLK(zp->z_mode) || S_ISCHR(zp->z_mode))
1621                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_RDEV(zfsvfs), NULL,
1622                     &rdev, 8);
1623 
1624         if (zp->z_acl_cached != NULL) {
1625                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_DACL_COUNT(zfsvfs), NULL,
1626                     &zp->z_acl_cached->z_acl_count, 8);
1627                 if (zp->z_acl_cached->z_version < ZFS_ACL_VERSION_FUID)
1628                         zfs_acl_xform(zp, zp->z_acl_cached, CRED());
1629                 locate.cb_aclp = zp->z_acl_cached;
1630                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_DACL_ACES(zfsvfs),
1631                     zfs_acl_data_locator, &locate,
1632                     zp->z_acl_cached->z_acl_bytes);
1633         }
1634 
1635         if (xattr)
1636                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_XATTR(zfsvfs), NULL,
1637                     &xattr, 8);
1638 
1639         if (zp->z_pflags & ZFS_BONUS_SCANSTAMP) {
1640                 bcopy((caddr_t)db->db_data + ZFS_OLD_ZNODE_PHYS_SIZE,
1641                     scanstamp, AV_SCANSTAMP_SZ);
1642                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_SCANSTAMP(zfsvfs), NULL,
1643                     scanstamp, AV_SCANSTAMP_SZ);
1644                 zp->z_pflags &= ~ZFS_BONUS_SCANSTAMP;
1645         }
1646 
1647         VERIFY(dmu_set_bonustype(db, DMU_OT_SA, tx) == 0);
1648         VERIFY(sa_replace_all_by_template_locked(hdl, attrs, count, tx) == 0);
1649         if (znode_acl.z_acl_extern_obj) {
1650                 VERIFY(0 == dmu_object_free(zfsvfs->z_os,
1651                     znode_acl.z_acl_extern_obj, tx));
1652         }
1653 
1654         zp->z_is_sa = B_TRUE;
1655 
1656 out:
1657         mutex_exit(&zp->z_lock);
1658         mutex_exit(&hdl->sa_lock);
1659         kmem_free(attrs, sizeof (sa_bulk_attr_t) * ZPL_END);
1660         kmem_free(bulk, sizeof (sa_bulk_attr_t) * ZPL_END);
1661         return (err);
1662 }
1663 #endif
1664 
1665 static sa_idx_tab_t *
1666 sa_find_idx_tab(objset_t *os, dmu_object_type_t bonustype, sa_hdr_phys_t *hdr)
1667 {
1668         sa_idx_tab_t *idx_tab;
1669         sa_os_t *sa = os->os_sa;
1670         sa_lot_t *tb, search;
1671         avl_index_t loc;
1672 
1673         /*
1674          * Deterimine layout number.  If SA node and header == 0 then
1675          * force the index table to the dummy "1" empty layout.
1676          *
1677          * The layout number would only be zero for a newly created file
1678          * that has not added any attributes yet, or with crypto enabled which
1679          * doesn't write any attributes to the bonus buffer.
1680          */
1681 
1682         search.lot_num = SA_LAYOUT_NUM(hdr, bonustype);
1683 
1684         tb = avl_find(&sa->sa_layout_num_tree, &search, &loc);
1685 
1686         /* Verify header size is consistent with layout information */
1687         ASSERT(tb);
1688         ASSERT(IS_SA_BONUSTYPE(bonustype) &&
1689             SA_HDR_SIZE_MATCH_LAYOUT(hdr, tb) || !IS_SA_BONUSTYPE(bonustype) ||
1690             (IS_SA_BONUSTYPE(bonustype) && hdr->sa_layout_info == 0));
1691 
1692         /*
1693          * See if any of the already existing TOC entries can be reused?
1694          */
1695 
1696         for (idx_tab = list_head(&tb->lot_idx_tab); idx_tab;
1697             idx_tab = list_next(&tb->lot_idx_tab, idx_tab)) {
1698                 boolean_t valid_idx = B_TRUE;
1699                 int i;
1700 
1701                 if (tb->lot_var_sizes != 0 &&
1702                     idx_tab->sa_variable_lengths != NULL) {
1703                         for (i = 0; i != tb->lot_var_sizes; i++) {
1704                                 if (hdr->sa_lengths[i] !=
1705                                     idx_tab->sa_variable_lengths[i]) {
1706                                         valid_idx = B_FALSE;
1707                                         break;
1708                                 }
1709                         }
1710                 }
1711                 if (valid_idx) {
1712                         sa_idx_tab_hold(os, idx_tab);
1713                         return (idx_tab);
1714                 }
1715         }
1716 
1717         /* No such luck, create a new entry */
1718         idx_tab = kmem_zalloc(sizeof (sa_idx_tab_t), KM_SLEEP);
1719         idx_tab->sa_idx_tab =
1720             kmem_zalloc(sizeof (uint32_t) * sa->sa_num_attrs, KM_SLEEP);
1721         idx_tab->sa_layout = tb;
1722         zfs_refcount_create(&idx_tab->sa_refcount);
1723         if (tb->lot_var_sizes)
1724                 idx_tab->sa_variable_lengths = kmem_alloc(sizeof (uint16_t) *
1725                     tb->lot_var_sizes, KM_SLEEP);
1726 
1727         sa_attr_iter(os, hdr, bonustype, sa_build_idx_tab,
1728             tb, idx_tab);
1729         sa_idx_tab_hold(os, idx_tab);   /* one hold for consumer */
1730         sa_idx_tab_hold(os, idx_tab);   /* one for layout */
1731         list_insert_tail(&tb->lot_idx_tab, idx_tab);
1732         return (idx_tab);
1733 }
1734 
1735 void
1736 sa_default_locator(void **dataptr, uint32_t *len, uint32_t total_len,
1737     boolean_t start, void *userdata)
1738 {
1739         ASSERT(start);
1740 
1741         *dataptr = userdata;
1742         *len = total_len;
1743 }
1744 
1745 static void
1746 sa_attr_register_sync(sa_handle_t *hdl, dmu_tx_t *tx)
1747 {
1748         uint64_t attr_value = 0;
1749         sa_os_t *sa = hdl->sa_os->os_sa;
1750         sa_attr_table_t *tb = sa->sa_attr_table;
1751         int i;
1752 
1753         mutex_enter(&sa->sa_lock);
1754 
1755         if (!sa->sa_need_attr_registration || sa->sa_master_obj == 0) {
1756                 mutex_exit(&sa->sa_lock);
1757                 return;
1758         }
1759 
1760         if (sa->sa_reg_attr_obj == 0) {
1761                 sa->sa_reg_attr_obj = zap_create_link(hdl->sa_os,
1762                     DMU_OT_SA_ATTR_REGISTRATION,
1763                     sa->sa_master_obj, SA_REGISTRY, tx);
1764         }
1765         for (i = 0; i != sa->sa_num_attrs; i++) {
1766                 if (sa->sa_attr_table[i].sa_registered)
1767                         continue;
1768                 ATTR_ENCODE(attr_value, tb[i].sa_attr, tb[i].sa_length,
1769                     tb[i].sa_byteswap);
1770                 VERIFY(0 == zap_update(hdl->sa_os, sa->sa_reg_attr_obj,
1771                     tb[i].sa_name, 8, 1, &attr_value, tx));
1772                 tb[i].sa_registered = B_TRUE;
1773         }
1774         sa->sa_need_attr_registration = B_FALSE;
1775         mutex_exit(&sa->sa_lock);
1776 }
1777 
1778 /*
1779  * Replace all attributes with attributes specified in template.
1780  * If dnode had a spill buffer then those attributes will be
1781  * also be replaced, possibly with just an empty spill block
1782  *
1783  * This interface is intended to only be used for bulk adding of
1784  * attributes for a new file.  It will also be used by the ZPL
1785  * when converting and old formatted znode to native SA support.
1786  */
1787 int
1788 sa_replace_all_by_template_locked(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc,
1789     int attr_count, dmu_tx_t *tx)
1790 {
1791         sa_os_t *sa = hdl->sa_os->os_sa;
1792 
1793         if (sa->sa_need_attr_registration)
1794                 sa_attr_register_sync(hdl, tx);
1795         return (sa_build_layouts(hdl, attr_desc, attr_count, tx));
1796 }
1797 
1798 int
1799 sa_replace_all_by_template(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc,
1800     int attr_count, dmu_tx_t *tx)
1801 {
1802         int error;
1803 
1804         mutex_enter(&hdl->sa_lock);
1805         error = sa_replace_all_by_template_locked(hdl, attr_desc,
1806             attr_count, tx);
1807         mutex_exit(&hdl->sa_lock);
1808         return (error);
1809 }
1810 
1811 /*
1812  * Add/remove a single attribute or replace a variable-sized attribute value
1813  * with a value of a different size, and then rewrite the entire set
1814  * of attributes.
1815  * Same-length attribute value replacement (including fixed-length attributes)
1816  * is handled more efficiently by the upper layers.
1817  */
1818 static int
1819 sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr,
1820     sa_data_op_t action, sa_data_locator_t *locator, void *datastart,
1821     uint16_t buflen, dmu_tx_t *tx)
1822 {
1823         sa_os_t *sa = hdl->sa_os->os_sa;
1824         dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus;
1825         dnode_t *dn;
1826         sa_bulk_attr_t *attr_desc;
1827         void *old_data[2];
1828         int bonus_attr_count = 0;
1829         int bonus_data_size = 0;
1830         int spill_data_size = 0;
1831         int spill_attr_count = 0;
1832         int error;
1833         uint16_t length, reg_length;
1834         int i, j, k, length_idx;
1835         sa_hdr_phys_t *hdr;
1836         sa_idx_tab_t *idx_tab;
1837         int attr_count;
1838         int count;
1839 
1840         ASSERT(MUTEX_HELD(&hdl->sa_lock));
1841 
1842         /* First make of copy of the old data */
1843 
1844         DB_DNODE_ENTER(db);
1845         dn = DB_DNODE(db);
1846         if (dn->dn_bonuslen != 0) {
1847                 bonus_data_size = hdl->sa_bonus->db_size;
1848                 old_data[0] = kmem_alloc(bonus_data_size, KM_SLEEP);
1849                 bcopy(hdl->sa_bonus->db_data, old_data[0],
1850                     hdl->sa_bonus->db_size);
1851                 bonus_attr_count = hdl->sa_bonus_tab->sa_layout->lot_attr_count;
1852         } else {
1853                 old_data[0] = NULL;
1854         }
1855         DB_DNODE_EXIT(db);
1856 
1857         /* Bring spill buffer online if it isn't currently */
1858 
1859         if ((error = sa_get_spill(hdl)) == 0) {
1860                 spill_data_size = hdl->sa_spill->db_size;
1861                 old_data[1] = kmem_alloc(spill_data_size, KM_SLEEP);
1862                 bcopy(hdl->sa_spill->db_data, old_data[1],
1863                     hdl->sa_spill->db_size);
1864                 spill_attr_count =
1865                     hdl->sa_spill_tab->sa_layout->lot_attr_count;
1866         } else if (error && error != ENOENT) {
1867                 if (old_data[0])
1868                         kmem_free(old_data[0], bonus_data_size);
1869                 return (error);
1870         } else {
1871                 old_data[1] = NULL;
1872         }
1873 
1874         /* build descriptor of all attributes */
1875 
1876         attr_count = bonus_attr_count + spill_attr_count;
1877         if (action == SA_ADD)
1878                 attr_count++;
1879         else if (action == SA_REMOVE)
1880                 attr_count--;
1881 
1882         attr_desc = kmem_zalloc(sizeof (sa_bulk_attr_t) * attr_count, KM_SLEEP);
1883 
1884         /*
1885          * loop through bonus and spill buffer if it exists, and
1886          * build up new attr_descriptor to reset the attributes
1887          */
1888         k = j = 0;
1889         count = bonus_attr_count;
1890         hdr = SA_GET_HDR(hdl, SA_BONUS);
1891         idx_tab = SA_IDX_TAB_GET(hdl, SA_BONUS);
1892         for (; k != 2; k++) {
1893                 /*
1894                  * Iterate over each attribute in layout.  Fetch the
1895                  * size of variable-length attributes needing rewrite
1896                  * from sa_lengths[].
1897                  */
1898                 for (i = 0, length_idx = 0; i != count; i++) {
1899                         sa_attr_type_t attr;
1900 
1901                         attr = idx_tab->sa_layout->lot_attrs[i];
1902                         reg_length = SA_REGISTERED_LEN(sa, attr);
1903                         if (reg_length == 0) {
1904                                 length = hdr->sa_lengths[length_idx];
1905                                 length_idx++;
1906                         } else {
1907                                 length = reg_length;
1908                         }
1909                         if (attr == newattr) {
1910                                 /*
1911                                  * There is nothing to do for SA_REMOVE,
1912                                  * so it is just skipped.
1913                                  */
1914                                 if (action == SA_REMOVE)
1915                                         continue;
1916 
1917                                 /*
1918                                  * Duplicate attributes are not allowed, so the
1919                                  * action can not be SA_ADD here.
1920                                  */
1921                                 ASSERT3S(action, ==, SA_REPLACE);
1922 
1923                                 /*
1924                                  * Only a variable-sized attribute can be
1925                                  * replaced here, and its size must be changing.
1926                                  */
1927                                 ASSERT3U(reg_length, ==, 0);
1928                                 ASSERT3U(length, !=, buflen);
1929                                 SA_ADD_BULK_ATTR(attr_desc, j, attr,
1930                                     locator, datastart, buflen);
1931                         } else {
1932                                 SA_ADD_BULK_ATTR(attr_desc, j, attr,
1933                                     NULL, (void *)
1934                                     (TOC_OFF(idx_tab->sa_idx_tab[attr]) +
1935                                     (uintptr_t)old_data[k]), length);
1936                         }
1937                 }
1938                 if (k == 0 && hdl->sa_spill) {
1939                         hdr = SA_GET_HDR(hdl, SA_SPILL);
1940                         idx_tab = SA_IDX_TAB_GET(hdl, SA_SPILL);
1941                         count = spill_attr_count;
1942                 } else {
1943                         break;
1944                 }
1945         }
1946         if (action == SA_ADD) {
1947                 reg_length = SA_REGISTERED_LEN(sa, newattr);
1948                 IMPLY(reg_length != 0, reg_length == buflen);
1949                 SA_ADD_BULK_ATTR(attr_desc, j, newattr, locator,
1950                     datastart, buflen);
1951         }
1952         ASSERT3U(j, ==, attr_count);
1953 
1954         error = sa_build_layouts(hdl, attr_desc, attr_count, tx);
1955 
1956         if (old_data[0])
1957                 kmem_free(old_data[0], bonus_data_size);
1958         if (old_data[1])
1959                 kmem_free(old_data[1], spill_data_size);
1960         kmem_free(attr_desc, sizeof (sa_bulk_attr_t) * attr_count);
1961 
1962         return (error);
1963 }
1964 
1965 static int
1966 sa_bulk_update_impl(sa_handle_t *hdl, sa_bulk_attr_t *bulk, int count,
1967     dmu_tx_t *tx)
1968 {
1969         int error;
1970         sa_os_t *sa = hdl->sa_os->os_sa;
1971         dmu_object_type_t bonustype;
1972 
1973         bonustype = SA_BONUSTYPE_FROM_DB(SA_GET_DB(hdl, SA_BONUS));
1974 
1975         ASSERT(hdl);
1976         ASSERT(MUTEX_HELD(&hdl->sa_lock));
1977 
1978         /* sync out registration table if necessary */
1979         if (sa->sa_need_attr_registration)
1980                 sa_attr_register_sync(hdl, tx);
1981 
1982         error = sa_attr_op(hdl, bulk, count, SA_UPDATE, tx);
1983         if (error == 0 && !IS_SA_BONUSTYPE(bonustype) && sa->sa_update_cb)
1984                 sa->sa_update_cb(hdl, tx);
1985 
1986         return (error);
1987 }
1988 
1989 /*
1990  * update or add new attribute
1991  */
1992 int
1993 sa_update(sa_handle_t *hdl, sa_attr_type_t type,
1994     void *buf, uint32_t buflen, dmu_tx_t *tx)
1995 {
1996         int error;
1997         sa_bulk_attr_t bulk;
1998 
1999         bulk.sa_attr = type;
2000         bulk.sa_data_func = NULL;
2001         bulk.sa_length = buflen;
2002         bulk.sa_data = buf;
2003 
2004         mutex_enter(&hdl->sa_lock);
2005         error = sa_bulk_update_impl(hdl, &bulk, 1, tx);
2006         mutex_exit(&hdl->sa_lock);
2007         return (error);
2008 }
2009 
2010 int
2011 sa_update_from_cb(sa_handle_t *hdl, sa_attr_type_t attr,
2012     uint32_t buflen, sa_data_locator_t *locator, void *userdata, dmu_tx_t *tx)
2013 {
2014         int error;
2015         sa_bulk_attr_t bulk;
2016 
2017         bulk.sa_attr = attr;
2018         bulk.sa_data = userdata;
2019         bulk.sa_data_func = locator;
2020         bulk.sa_length = buflen;
2021 
2022         mutex_enter(&hdl->sa_lock);
2023         error = sa_bulk_update_impl(hdl, &bulk, 1, tx);
2024         mutex_exit(&hdl->sa_lock);
2025         return (error);
2026 }
2027 
2028 /*
2029  * Return size of an attribute
2030  */
2031 
2032 int
2033 sa_size(sa_handle_t *hdl, sa_attr_type_t attr, int *size)
2034 {
2035         sa_bulk_attr_t bulk;
2036         int error;
2037 
2038         bulk.sa_data = NULL;
2039         bulk.sa_attr = attr;
2040         bulk.sa_data_func = NULL;
2041 
2042         ASSERT(hdl);
2043         mutex_enter(&hdl->sa_lock);
2044         if ((error = sa_attr_op(hdl, &bulk, 1, SA_LOOKUP, NULL)) != 0) {
2045                 mutex_exit(&hdl->sa_lock);
2046                 return (error);
2047         }
2048         *size = bulk.sa_size;
2049 
2050         mutex_exit(&hdl->sa_lock);
2051         return (0);
2052 }
2053 
2054 int
2055 sa_bulk_lookup_locked(sa_handle_t *hdl, sa_bulk_attr_t *attrs, int count)
2056 {
2057         ASSERT(hdl);
2058         ASSERT(MUTEX_HELD(&hdl->sa_lock));
2059         return (sa_lookup_impl(hdl, attrs, count));
2060 }
2061 
2062 int
2063 sa_bulk_lookup(sa_handle_t *hdl, sa_bulk_attr_t *attrs, int count)
2064 {
2065         int error;
2066 
2067         ASSERT(hdl);
2068         mutex_enter(&hdl->sa_lock);
2069         error = sa_bulk_lookup_locked(hdl, attrs, count);
2070         mutex_exit(&hdl->sa_lock);
2071         return (error);
2072 }
2073 
2074 int
2075 sa_bulk_update(sa_handle_t *hdl, sa_bulk_attr_t *attrs, int count, dmu_tx_t *tx)
2076 {
2077         int error;
2078 
2079         ASSERT(hdl);
2080         mutex_enter(&hdl->sa_lock);
2081         error = sa_bulk_update_impl(hdl, attrs, count, tx);
2082         mutex_exit(&hdl->sa_lock);
2083         return (error);
2084 }
2085 
2086 int
2087 sa_remove(sa_handle_t *hdl, sa_attr_type_t attr, dmu_tx_t *tx)
2088 {
2089         int error;
2090 
2091         mutex_enter(&hdl->sa_lock);
2092         error = sa_modify_attrs(hdl, attr, SA_REMOVE, NULL,
2093             NULL, 0, tx);
2094         mutex_exit(&hdl->sa_lock);
2095         return (error);
2096 }
2097 
2098 void
2099 sa_object_info(sa_handle_t *hdl, dmu_object_info_t *doi)
2100 {
2101         dmu_object_info_from_db((dmu_buf_t *)hdl->sa_bonus, doi);
2102 }
2103 
2104 void
2105 sa_object_size(sa_handle_t *hdl, uint32_t *blksize, u_longlong_t *nblocks)
2106 {
2107         dmu_object_size_from_db((dmu_buf_t *)hdl->sa_bonus,
2108             blksize, nblocks);
2109 }
2110 
2111 void
2112 sa_set_userp(sa_handle_t *hdl, void *ptr)
2113 {
2114         hdl->sa_userp = ptr;
2115 }
2116 
2117 dmu_buf_t *
2118 sa_get_db(sa_handle_t *hdl)
2119 {
2120         return ((dmu_buf_t *)hdl->sa_bonus);
2121 }
2122 
2123 void *
2124 sa_get_userdata(sa_handle_t *hdl)
2125 {
2126         return (hdl->sa_userp);
2127 }
2128 
2129 void
2130 sa_register_update_callback_locked(objset_t *os, sa_update_cb_t *func)
2131 {
2132         ASSERT(MUTEX_HELD(&os->os_sa->sa_lock));
2133         os->os_sa->sa_update_cb = func;
2134 }
2135 
2136 void
2137 sa_register_update_callback(objset_t *os, sa_update_cb_t *func)
2138 {
2139 
2140         mutex_enter(&os->os_sa->sa_lock);
2141         sa_register_update_callback_locked(os, func);
2142         mutex_exit(&os->os_sa->sa_lock);
2143 }
2144 
2145 uint64_t
2146 sa_handle_object(sa_handle_t *hdl)
2147 {
2148         return (hdl->sa_bonus->db_object);
2149 }
2150 
2151 boolean_t
2152 sa_enabled(objset_t *os)
2153 {
2154         return (os->os_sa == NULL);
2155 }
2156 
2157 int
2158 sa_set_sa_object(objset_t *os, uint64_t sa_object)
2159 {
2160         sa_os_t *sa = os->os_sa;
2161 
2162         if (sa->sa_master_obj)
2163                 return (1);
2164 
2165         sa->sa_master_obj = sa_object;
2166 
2167         return (0);
2168 }
2169 
2170 int
2171 sa_hdrsize(void *arg)
2172 {
2173         sa_hdr_phys_t *hdr = arg;
2174 
2175         return (SA_HDR_SIZE(hdr));
2176 }
2177 
2178 void
2179 sa_handle_lock(sa_handle_t *hdl)
2180 {
2181         ASSERT(hdl);
2182         mutex_enter(&hdl->sa_lock);
2183 }
2184 
2185 void
2186 sa_handle_unlock(sa_handle_t *hdl)
2187 {
2188         ASSERT(hdl);
2189         mutex_exit(&hdl->sa_lock);
2190 }