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, size;
 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 
 415         if ((size = sizeof (sa_attr_type_t) * attr_count) != 0) {
 416                 tb->lot_attrs = kmem_alloc(size, KM_SLEEP);
 417                 bcopy(attrs, tb->lot_attrs, size);
 418         }
 419 
 420         tb->lot_num = lot_num;
 421         tb->lot_hash = hash;
 422         tb->lot_instance = 0;
 423 
 424         if (zapadd) {
 425                 char attr_name[8];
 426 
 427                 if (sa->sa_layout_attr_obj == 0) {
 428                         sa->sa_layout_attr_obj = zap_create_link(os,
 429                             DMU_OT_SA_ATTR_LAYOUTS,
 430                             sa->sa_master_obj, SA_LAYOUTS, tx);
 431                 }
 432 
 433                 (void) snprintf(attr_name, sizeof (attr_name),
 434                     "%d", (int)lot_num);
 435                 VERIFY(0 == zap_update(os, os->os_sa->sa_layout_attr_obj,
 436                     attr_name, 2, attr_count, attrs, tx));
 437         }
 438 
 439         list_create(&tb->lot_idx_tab, sizeof (sa_idx_tab_t),
 440             offsetof(sa_idx_tab_t, sa_next));
 441 
 442         for (i = 0; i != attr_count; i++) {
 443                 if (sa->sa_attr_table[tb->lot_attrs[i]].sa_length == 0)
 444                         tb->lot_var_sizes++;
 445         }
 446 
 447         avl_add(&sa->sa_layout_num_tree, tb);
 448 
 449         /* verify we don't have a hash collision */
 450         if ((findtb = avl_find(&sa->sa_layout_hash_tree, tb, &loc)) != NULL) {
 451                 for (; findtb && findtb->lot_hash == hash;
 452                     findtb = AVL_NEXT(&sa->sa_layout_hash_tree, findtb)) {
 453                         if (findtb->lot_instance != tb->lot_instance)
 454                                 break;
 455                         tb->lot_instance++;
 456                 }
 457         }
 458         avl_add(&sa->sa_layout_hash_tree, tb);
 459         return (tb);
 460 }
 461 
 462 static void
 463 sa_find_layout(objset_t *os, uint64_t hash, sa_attr_type_t *attrs,
 464     int count, dmu_tx_t *tx, sa_lot_t **lot)
 465 {
 466         sa_lot_t *tb, tbsearch;
 467         avl_index_t loc;
 468         sa_os_t *sa = os->os_sa;
 469         boolean_t found = B_FALSE;
 470 
 471         mutex_enter(&sa->sa_lock);
 472         tbsearch.lot_hash = hash;
 473         tbsearch.lot_instance = 0;
 474         tb = avl_find(&sa->sa_layout_hash_tree, &tbsearch, &loc);
 475         if (tb) {
 476                 for (; tb && tb->lot_hash == hash;
 477                     tb = AVL_NEXT(&sa->sa_layout_hash_tree, tb)) {
 478                         if (sa_layout_equal(tb, attrs, count) == 0) {
 479                                 found = B_TRUE;
 480                                 break;
 481                         }
 482                 }
 483         }
 484         if (!found) {
 485                 tb = sa_add_layout_entry(os, attrs, count,
 486                     avl_numnodes(&sa->sa_layout_num_tree), hash, B_TRUE, tx);
 487         }
 488         mutex_exit(&sa->sa_lock);
 489         *lot = tb;
 490 }
 491 
 492 static int
 493 sa_resize_spill(sa_handle_t *hdl, uint32_t size, dmu_tx_t *tx)
 494 {
 495         int error;
 496         uint32_t blocksize;
 497 
 498         if (size == 0) {
 499                 blocksize = SPA_MINBLOCKSIZE;
 500         } else if (size > SPA_OLD_MAXBLOCKSIZE) {
 501                 ASSERT(0);
 502                 return (SET_ERROR(EFBIG));
 503         } else {
 504                 blocksize = P2ROUNDUP_TYPED(size, SPA_MINBLOCKSIZE, uint32_t);
 505         }
 506 
 507         error = dbuf_spill_set_blksz(hdl->sa_spill, blocksize, tx);
 508         ASSERT(error == 0);
 509         return (error);
 510 }
 511 
 512 static void
 513 sa_copy_data(sa_data_locator_t *func, void *datastart, void *target, int buflen)
 514 {
 515         if (func == NULL) {
 516                 bcopy(datastart, target, buflen);
 517         } else {
 518                 boolean_t start;
 519                 int bytes;
 520                 void *dataptr;
 521                 void *saptr = target;
 522                 uint32_t length;
 523 
 524                 start = B_TRUE;
 525                 bytes = 0;
 526                 while (bytes < buflen) {
 527                         func(&dataptr, &length, buflen, start, datastart);
 528                         bcopy(dataptr, saptr, length);
 529                         saptr = (void *)((caddr_t)saptr + length);
 530                         bytes += length;
 531                         start = B_FALSE;
 532                 }
 533         }
 534 }
 535 
 536 /*
 537  * Determine several different sizes
 538  * first the sa header size
 539  * the number of bytes to be stored
 540  * if spill would occur the index in the attribute array is returned
 541  *
 542  * the boolean will_spill will be set when spilling is necessary.  It
 543  * is only set when the buftype is SA_BONUS
 544  */
 545 static int
 546 sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
 547     dmu_buf_t *db, sa_buf_type_t buftype, int full_space, int *index,
 548     int *total, boolean_t *will_spill)
 549 {
 550         int var_size = 0;
 551         int i;
 552         int hdrsize;
 553         int extra_hdrsize;
 554 
 555         if (buftype == SA_BONUS && sa->sa_force_spill) {
 556                 *total = 0;
 557                 *index = 0;
 558                 *will_spill = B_TRUE;
 559                 return (0);
 560         }
 561 
 562         *index = -1;
 563         *total = 0;
 564         *will_spill = B_FALSE;
 565 
 566         extra_hdrsize = 0;
 567         hdrsize = (SA_BONUSTYPE_FROM_DB(db) == DMU_OT_ZNODE) ? 0 :
 568             sizeof (sa_hdr_phys_t);
 569 
 570         ASSERT(IS_P2ALIGNED(full_space, 8));
 571 
 572         for (i = 0; i != attr_count; i++) {
 573                 boolean_t is_var_sz;
 574 
 575                 *total = P2ROUNDUP(*total, 8);
 576                 *total += attr_desc[i].sa_length;
 577                 if (*will_spill)
 578                         continue;
 579 
 580                 is_var_sz = (SA_REGISTERED_LEN(sa, attr_desc[i].sa_attr) == 0);
 581                 if (is_var_sz) {
 582                         var_size++;
 583                 }
 584 
 585                 if (is_var_sz && var_size > 1) {
 586                         /*
 587                          * Don't worry that the spill block might overflow.
 588                          * It will be resized if needed in sa_build_layouts().
 589                          */
 590                         if (buftype == SA_SPILL ||
 591                             P2ROUNDUP(hdrsize + sizeof (uint16_t), 8) +
 592                             *total < full_space) {
 593                                 /*
 594                                  * Account for header space used by array of
 595                                  * optional sizes of variable-length attributes.
 596                                  * Record the extra header size in case this
 597                                  * increase needs to be reversed due to
 598                                  * spill-over.
 599                                  */
 600                                 hdrsize += sizeof (uint16_t);
 601                                 if (*index != -1)
 602                                         extra_hdrsize += sizeof (uint16_t);
 603                         } else {
 604                                 ASSERT(buftype == SA_BONUS);
 605                                 if (*index == -1)
 606                                         *index = i;
 607                                 *will_spill = B_TRUE;
 608                                 continue;
 609                         }
 610                 }
 611 
 612                 /*
 613                  * find index of where spill *could* occur.
 614                  * Then continue to count of remainder attribute
 615                  * space.  The sum is used later for sizing bonus
 616                  * and spill buffer.
 617                  */
 618                 if (buftype == SA_BONUS && *index == -1 &&
 619                     *total + P2ROUNDUP(hdrsize, 8) >
 620                     (full_space - sizeof (blkptr_t))) {
 621                         *index = i;
 622                 }
 623 
 624                 if (*total + P2ROUNDUP(hdrsize, 8) > full_space &&
 625                     buftype == SA_BONUS)
 626                         *will_spill = B_TRUE;
 627         }
 628 
 629         if (*will_spill)
 630                 hdrsize -= extra_hdrsize;
 631 
 632         hdrsize = P2ROUNDUP(hdrsize, 8);
 633         return (hdrsize);
 634 }
 635 
 636 #define BUF_SPACE_NEEDED(total, header) (total + header)
 637 
 638 /*
 639  * Find layout that corresponds to ordering of attributes
 640  * If not found a new layout number is created and added to
 641  * persistent layout tables.
 642  */
 643 static int
 644 sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
 645     dmu_tx_t *tx)
 646 {
 647         sa_os_t *sa = hdl->sa_os->os_sa;
 648         uint64_t hash;
 649         sa_buf_type_t buftype;
 650         sa_hdr_phys_t *sahdr;
 651         void *data_start;
 652         int buf_space;
 653         sa_attr_type_t *attrs, *attrs_start;
 654         int i, lot_count;
 655         int dnodesize;
 656         int hdrsize;
 657         int spillhdrsize = 0;
 658         int used;
 659         dmu_object_type_t bonustype;
 660         sa_lot_t *lot;
 661         int len_idx;
 662         int spill_used;
 663         int bonuslen;
 664         boolean_t spilling;
 665 
 666         dmu_buf_will_dirty(hdl->sa_bonus, tx);
 667         bonustype = SA_BONUSTYPE_FROM_DB(hdl->sa_bonus);
 668 
 669         dmu_object_dnsize_from_db(hdl->sa_bonus, &dnodesize);
 670         bonuslen = DN_BONUS_SIZE(dnodesize);
 671 
 672         /* first determine bonus header size and sum of all attributes */
 673         hdrsize = sa_find_sizes(sa, attr_desc, attr_count, hdl->sa_bonus,
 674             SA_BONUS, bonuslen, &i, &used, &spilling);
 675 
 676         if (used > SPA_OLD_MAXBLOCKSIZE)
 677                 return (SET_ERROR(EFBIG));
 678 
 679         VERIFY(0 == dmu_set_bonus(hdl->sa_bonus, spilling ?
 680             MIN(bonuslen - sizeof (blkptr_t), used + hdrsize) :
 681             used + hdrsize, tx));
 682 
 683         ASSERT((bonustype == DMU_OT_ZNODE && spilling == 0) ||
 684             bonustype == DMU_OT_SA);
 685 
 686         /* setup and size spill buffer when needed */
 687         if (spilling) {
 688                 boolean_t dummy;
 689 
 690                 if (hdl->sa_spill == NULL) {
 691                         VERIFY(dmu_spill_hold_by_bonus(hdl->sa_bonus, 0, NULL,
 692                             &hdl->sa_spill) == 0);
 693                 }
 694                 dmu_buf_will_dirty(hdl->sa_spill, tx);
 695 
 696                 spillhdrsize = sa_find_sizes(sa, &attr_desc[i],
 697                     attr_count - i, hdl->sa_spill, SA_SPILL,
 698                     hdl->sa_spill->db_size, &i, &spill_used, &dummy);
 699 
 700                 if (spill_used > SPA_OLD_MAXBLOCKSIZE)
 701                         return (SET_ERROR(EFBIG));
 702 
 703                 buf_space = hdl->sa_spill->db_size - spillhdrsize;
 704                 if (BUF_SPACE_NEEDED(spill_used, spillhdrsize) >
 705                     hdl->sa_spill->db_size)
 706                         VERIFY(0 == sa_resize_spill(hdl,
 707                             BUF_SPACE_NEEDED(spill_used, spillhdrsize), tx));
 708         }
 709 
 710         /* setup starting pointers to lay down data */
 711         data_start = (void *)((uintptr_t)hdl->sa_bonus->db_data + hdrsize);
 712         sahdr = (sa_hdr_phys_t *)hdl->sa_bonus->db_data;
 713         buftype = SA_BONUS;
 714 
 715         if (spilling)
 716                 buf_space = (sa->sa_force_spill) ?
 717                     0 : SA_BLKPTR_SPACE - hdrsize;
 718         else
 719                 buf_space = hdl->sa_bonus->db_size - hdrsize;
 720 
 721         attrs_start = attrs = kmem_alloc(sizeof (sa_attr_type_t) * attr_count,
 722             KM_SLEEP);
 723         lot_count = 0;
 724 
 725         for (i = 0, len_idx = 0, hash = -1ULL; i != attr_count; i++) {
 726                 uint16_t length;
 727 
 728                 ASSERT(IS_P2ALIGNED(data_start, 8));
 729                 ASSERT(IS_P2ALIGNED(buf_space, 8));
 730                 attrs[i] = attr_desc[i].sa_attr;
 731                 length = SA_REGISTERED_LEN(sa, attrs[i]);
 732                 if (length == 0)
 733                         length = attr_desc[i].sa_length;
 734 
 735                 if (buf_space < length) {  /* switch to spill buffer */
 736                         VERIFY(spilling);
 737                         VERIFY(bonustype == DMU_OT_SA);
 738                         if (buftype == SA_BONUS && !sa->sa_force_spill) {
 739                                 sa_find_layout(hdl->sa_os, hash, attrs_start,
 740                                     lot_count, tx, &lot);
 741                                 SA_SET_HDR(sahdr, lot->lot_num, hdrsize);
 742                         }
 743 
 744                         buftype = SA_SPILL;
 745                         hash = -1ULL;
 746                         len_idx = 0;
 747 
 748                         sahdr = (sa_hdr_phys_t *)hdl->sa_spill->db_data;
 749                         sahdr->sa_magic = SA_MAGIC;
 750                         data_start = (void *)((uintptr_t)sahdr +
 751                             spillhdrsize);
 752                         attrs_start = &attrs[i];
 753                         buf_space = hdl->sa_spill->db_size - spillhdrsize;
 754                         lot_count = 0;
 755                 }
 756                 hash ^= SA_ATTR_HASH(attrs[i]);
 757                 attr_desc[i].sa_addr = data_start;
 758                 attr_desc[i].sa_size = length;
 759                 SA_COPY_DATA(attr_desc[i].sa_data_func, attr_desc[i].sa_data,
 760                     data_start, length);
 761                 if (sa->sa_attr_table[attrs[i]].sa_length == 0) {
 762                         sahdr->sa_lengths[len_idx++] = length;
 763                 }
 764                 data_start = (void *)P2ROUNDUP(((uintptr_t)data_start +
 765                     length), 8);
 766                 buf_space -= P2ROUNDUP(length, 8);
 767                 lot_count++;
 768         }
 769 
 770         sa_find_layout(hdl->sa_os, hash, attrs_start, lot_count, tx, &lot);
 771 
 772         /*
 773          * Verify that old znodes always have layout number 0.
 774          * Must be DMU_OT_SA for arbitrary layouts
 775          */
 776         VERIFY((bonustype == DMU_OT_ZNODE && lot->lot_num == 0) ||
 777             (bonustype == DMU_OT_SA && lot->lot_num > 1));
 778 
 779         if (bonustype == DMU_OT_SA) {
 780                 SA_SET_HDR(sahdr, lot->lot_num,
 781                     buftype == SA_BONUS ? hdrsize : spillhdrsize);
 782         }
 783 
 784         kmem_free(attrs, sizeof (sa_attr_type_t) * attr_count);
 785         if (hdl->sa_bonus_tab) {
 786                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_bonus_tab);
 787                 hdl->sa_bonus_tab = NULL;
 788         }
 789         if (!sa->sa_force_spill)
 790                 VERIFY(0 == sa_build_index(hdl, SA_BONUS));
 791         if (hdl->sa_spill) {
 792                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_spill_tab);
 793                 if (!spilling) {
 794                         /*
 795                          * remove spill block that is no longer needed.
 796                          */
 797                         dmu_buf_rele(hdl->sa_spill, NULL);
 798                         hdl->sa_spill = NULL;
 799                         hdl->sa_spill_tab = NULL;
 800                         VERIFY(0 == dmu_rm_spill(hdl->sa_os,
 801                             sa_handle_object(hdl), tx));
 802                 } else {
 803                         VERIFY(0 == sa_build_index(hdl, SA_SPILL));
 804                 }
 805         }
 806 
 807         return (0);
 808 }
 809 
 810 static void
 811 sa_free_attr_table(sa_os_t *sa)
 812 {
 813         int i;
 814 
 815         if (sa->sa_attr_table == NULL)
 816                 return;
 817 
 818         for (i = 0; i != sa->sa_num_attrs; i++) {
 819                 if (sa->sa_attr_table[i].sa_name)
 820                         kmem_free(sa->sa_attr_table[i].sa_name,
 821                             strlen(sa->sa_attr_table[i].sa_name) + 1);
 822         }
 823 
 824         kmem_free(sa->sa_attr_table,
 825             sizeof (sa_attr_table_t) * sa->sa_num_attrs);
 826 
 827         sa->sa_attr_table = NULL;
 828 }
 829 
 830 static int
 831 sa_attr_table_setup(objset_t *os, sa_attr_reg_t *reg_attrs, int count)
 832 {
 833         sa_os_t *sa = os->os_sa;
 834         uint64_t sa_attr_count = 0;
 835         uint64_t sa_reg_count = 0;
 836         int error = 0;
 837         uint64_t attr_value;
 838         sa_attr_table_t *tb;
 839         zap_cursor_t zc;
 840         zap_attribute_t za;
 841         int registered_count = 0;
 842         int i;
 843         dmu_objset_type_t ostype = dmu_objset_type(os);
 844 
 845         sa->sa_user_table =
 846             kmem_zalloc(count * sizeof (sa_attr_type_t), KM_SLEEP);
 847         sa->sa_user_table_sz = count * sizeof (sa_attr_type_t);
 848 
 849         if (sa->sa_reg_attr_obj != 0) {
 850                 error = zap_count(os, sa->sa_reg_attr_obj,
 851                     &sa_attr_count);
 852 
 853                 /*
 854                  * Make sure we retrieved a count and that it isn't zero
 855                  */
 856                 if (error || (error == 0 && sa_attr_count == 0)) {
 857                         if (error == 0)
 858                                 error = SET_ERROR(EINVAL);
 859                         goto bail;
 860                 }
 861                 sa_reg_count = sa_attr_count;
 862         }
 863 
 864         if (ostype == DMU_OST_ZFS && sa_attr_count == 0)
 865                 sa_attr_count += sa_legacy_attr_count;
 866 
 867         /* Allocate attribute numbers for attributes that aren't registered */
 868         for (i = 0; i != count; i++) {
 869                 boolean_t found = B_FALSE;
 870                 int j;
 871 
 872                 if (ostype == DMU_OST_ZFS) {
 873                         for (j = 0; j != sa_legacy_attr_count; j++) {
 874                                 if (strcmp(reg_attrs[i].sa_name,
 875                                     sa_legacy_attrs[j].sa_name) == 0) {
 876                                         sa->sa_user_table[i] =
 877                                             sa_legacy_attrs[j].sa_attr;
 878                                         found = B_TRUE;
 879                                 }
 880                         }
 881                 }
 882                 if (found)
 883                         continue;
 884 
 885                 if (sa->sa_reg_attr_obj)
 886                         error = zap_lookup(os, sa->sa_reg_attr_obj,
 887                             reg_attrs[i].sa_name, 8, 1, &attr_value);
 888                 else
 889                         error = SET_ERROR(ENOENT);
 890                 switch (error) {
 891                 case ENOENT:
 892                         sa->sa_user_table[i] = (sa_attr_type_t)sa_attr_count;
 893                         sa_attr_count++;
 894                         break;
 895                 case 0:
 896                         sa->sa_user_table[i] = ATTR_NUM(attr_value);
 897                         break;
 898                 default:
 899                         goto bail;
 900                 }
 901         }
 902 
 903         sa->sa_num_attrs = sa_attr_count;
 904         tb = sa->sa_attr_table =
 905             kmem_zalloc(sizeof (sa_attr_table_t) * sa_attr_count, KM_SLEEP);
 906 
 907         /*
 908          * Attribute table is constructed from requested attribute list,
 909          * previously foreign registered attributes, and also the legacy
 910          * ZPL set of attributes.
 911          */
 912 
 913         if (sa->sa_reg_attr_obj) {
 914                 for (zap_cursor_init(&zc, os, sa->sa_reg_attr_obj);
 915                     (error = zap_cursor_retrieve(&zc, &za)) == 0;
 916                     zap_cursor_advance(&zc)) {
 917                         uint64_t value;
 918                         value  = za.za_first_integer;
 919 
 920                         registered_count++;
 921                         tb[ATTR_NUM(value)].sa_attr = ATTR_NUM(value);
 922                         tb[ATTR_NUM(value)].sa_length = ATTR_LENGTH(value);
 923                         tb[ATTR_NUM(value)].sa_byteswap = ATTR_BSWAP(value);
 924                         tb[ATTR_NUM(value)].sa_registered = B_TRUE;
 925 
 926                         if (tb[ATTR_NUM(value)].sa_name) {
 927                                 continue;
 928                         }
 929                         tb[ATTR_NUM(value)].sa_name =
 930                             kmem_zalloc(strlen(za.za_name) +1, KM_SLEEP);
 931                         (void) strlcpy(tb[ATTR_NUM(value)].sa_name, za.za_name,
 932                             strlen(za.za_name) +1);
 933                 }
 934                 zap_cursor_fini(&zc);
 935                 /*
 936                  * Make sure we processed the correct number of registered
 937                  * attributes
 938                  */
 939                 if (registered_count != sa_reg_count) {
 940                         ASSERT(error != 0);
 941                         goto bail;
 942                 }
 943 
 944         }
 945 
 946         if (ostype == DMU_OST_ZFS) {
 947                 for (i = 0; i != sa_legacy_attr_count; i++) {
 948                         if (tb[i].sa_name)
 949                                 continue;
 950                         tb[i].sa_attr = sa_legacy_attrs[i].sa_attr;
 951                         tb[i].sa_length = sa_legacy_attrs[i].sa_length;
 952                         tb[i].sa_byteswap = sa_legacy_attrs[i].sa_byteswap;
 953                         tb[i].sa_registered = B_FALSE;
 954                         tb[i].sa_name =
 955                             kmem_zalloc(strlen(sa_legacy_attrs[i].sa_name) +1,
 956                             KM_SLEEP);
 957                         (void) strlcpy(tb[i].sa_name,
 958                             sa_legacy_attrs[i].sa_name,
 959                             strlen(sa_legacy_attrs[i].sa_name) + 1);
 960                 }
 961         }
 962 
 963         for (i = 0; i != count; i++) {
 964                 sa_attr_type_t attr_id;
 965 
 966                 attr_id = sa->sa_user_table[i];
 967                 if (tb[attr_id].sa_name)
 968                         continue;
 969 
 970                 tb[attr_id].sa_length = reg_attrs[i].sa_length;
 971                 tb[attr_id].sa_byteswap = reg_attrs[i].sa_byteswap;
 972                 tb[attr_id].sa_attr = attr_id;
 973                 tb[attr_id].sa_name =
 974                     kmem_zalloc(strlen(reg_attrs[i].sa_name) + 1, KM_SLEEP);
 975                 (void) strlcpy(tb[attr_id].sa_name, reg_attrs[i].sa_name,
 976                     strlen(reg_attrs[i].sa_name) + 1);
 977         }
 978 
 979         sa->sa_need_attr_registration =
 980             (sa_attr_count != registered_count);
 981 
 982         return (0);
 983 bail:
 984         kmem_free(sa->sa_user_table, count * sizeof (sa_attr_type_t));
 985         sa->sa_user_table = NULL;
 986         sa_free_attr_table(sa);
 987         return ((error != 0) ? error : EINVAL);
 988 }
 989 
 990 int
 991 sa_setup(objset_t *os, uint64_t sa_obj, sa_attr_reg_t *reg_attrs, int count,
 992     sa_attr_type_t **user_table)
 993 {
 994         zap_cursor_t zc;
 995         zap_attribute_t za;
 996         sa_os_t *sa;
 997         dmu_objset_type_t ostype = dmu_objset_type(os);
 998         sa_attr_type_t *tb;
 999         int error;
1000 
1001         mutex_enter(&os->os_user_ptr_lock);
1002         if (os->os_sa) {
1003                 mutex_enter(&os->os_sa->sa_lock);
1004                 mutex_exit(&os->os_user_ptr_lock);
1005                 tb = os->os_sa->sa_user_table;
1006                 mutex_exit(&os->os_sa->sa_lock);
1007                 *user_table = tb;
1008                 return (0);
1009         }
1010 
1011         sa = kmem_zalloc(sizeof (sa_os_t), KM_SLEEP);
1012         mutex_init(&sa->sa_lock, NULL, MUTEX_DEFAULT, NULL);
1013         sa->sa_master_obj = sa_obj;
1014 
1015         os->os_sa = sa;
1016         mutex_enter(&sa->sa_lock);
1017         mutex_exit(&os->os_user_ptr_lock);
1018         avl_create(&sa->sa_layout_num_tree, layout_num_compare,
1019             sizeof (sa_lot_t), offsetof(sa_lot_t, lot_num_node));
1020         avl_create(&sa->sa_layout_hash_tree, layout_hash_compare,
1021             sizeof (sa_lot_t), offsetof(sa_lot_t, lot_hash_node));
1022 
1023         if (sa_obj) {
1024                 error = zap_lookup(os, sa_obj, SA_LAYOUTS,
1025                     8, 1, &sa->sa_layout_attr_obj);
1026                 if (error != 0 && error != ENOENT)
1027                         goto fail;
1028                 error = zap_lookup(os, sa_obj, SA_REGISTRY,
1029                     8, 1, &sa->sa_reg_attr_obj);
1030                 if (error != 0 && error != ENOENT)
1031                         goto fail;
1032         }
1033 
1034         if ((error = sa_attr_table_setup(os, reg_attrs, count)) != 0)
1035                 goto fail;
1036 
1037         if (sa->sa_layout_attr_obj != 0) {
1038                 uint64_t layout_count;
1039 
1040                 error = zap_count(os, sa->sa_layout_attr_obj,
1041                     &layout_count);
1042 
1043                 /*
1044                  * Layout number count should be > 0
1045                  */
1046                 if (error || (error == 0 && layout_count == 0)) {
1047                         if (error == 0)
1048                                 error = SET_ERROR(EINVAL);
1049                         goto fail;
1050                 }
1051 
1052                 for (zap_cursor_init(&zc, os, sa->sa_layout_attr_obj);
1053                     (error = zap_cursor_retrieve(&zc, &za)) == 0;
1054                     zap_cursor_advance(&zc)) {
1055                         sa_attr_type_t *lot_attrs;
1056                         uint64_t lot_num;
1057 
1058                         lot_attrs = kmem_zalloc(sizeof (sa_attr_type_t) *
1059                             za.za_num_integers, KM_SLEEP);
1060 
1061                         if ((error = (zap_lookup(os, sa->sa_layout_attr_obj,
1062                             za.za_name, 2, za.za_num_integers,
1063                             lot_attrs))) != 0) {
1064                                 kmem_free(lot_attrs, sizeof (sa_attr_type_t) *
1065                                     za.za_num_integers);
1066                                 break;
1067                         }
1068                         VERIFY(ddi_strtoull(za.za_name, NULL, 10,
1069                             (unsigned long long *)&lot_num) == 0);
1070 
1071                         (void) sa_add_layout_entry(os, lot_attrs,
1072                             za.za_num_integers, lot_num,
1073                             sa_layout_info_hash(lot_attrs,
1074                             za.za_num_integers), B_FALSE, NULL);
1075                         kmem_free(lot_attrs, sizeof (sa_attr_type_t) *
1076                             za.za_num_integers);
1077                 }
1078                 zap_cursor_fini(&zc);
1079 
1080                 /*
1081                  * Make sure layout count matches number of entries added
1082                  * to AVL tree
1083                  */
1084                 if (avl_numnodes(&sa->sa_layout_num_tree) != layout_count) {
1085                         ASSERT(error != 0);
1086                         goto fail;
1087                 }
1088         }
1089 
1090         /* Add special layout number for old ZNODES */
1091         if (ostype == DMU_OST_ZFS) {
1092                 (void) sa_add_layout_entry(os, sa_legacy_zpl_layout,
1093                     sa_legacy_attr_count, 0,
1094                     sa_layout_info_hash(sa_legacy_zpl_layout,
1095                     sa_legacy_attr_count), B_FALSE, NULL);
1096 
1097                 (void) sa_add_layout_entry(os, sa_dummy_zpl_layout, 0, 1,
1098                     0, B_FALSE, NULL);
1099         }
1100         *user_table = os->os_sa->sa_user_table;
1101         mutex_exit(&sa->sa_lock);
1102         return (0);
1103 fail:
1104         os->os_sa = NULL;
1105         sa_free_attr_table(sa);
1106         if (sa->sa_user_table)
1107                 kmem_free(sa->sa_user_table, sa->sa_user_table_sz);
1108         mutex_exit(&sa->sa_lock);
1109         avl_destroy(&sa->sa_layout_hash_tree);
1110         avl_destroy(&sa->sa_layout_num_tree);
1111         mutex_destroy(&sa->sa_lock);
1112         kmem_free(sa, sizeof (sa_os_t));
1113         return ((error == ECKSUM) ? EIO : error);
1114 }
1115 
1116 void
1117 sa_tear_down(objset_t *os)
1118 {
1119         sa_os_t *sa = os->os_sa;
1120         sa_lot_t *layout;
1121         void *cookie;
1122 
1123         kmem_free(sa->sa_user_table, sa->sa_user_table_sz);
1124 
1125         /* Free up attr table */
1126 
1127         sa_free_attr_table(sa);
1128 
1129         cookie = NULL;
1130         while (layout = avl_destroy_nodes(&sa->sa_layout_hash_tree, &cookie)) {
1131                 sa_idx_tab_t *tab;
1132                 while (tab = list_head(&layout->lot_idx_tab)) {
1133                         ASSERT(zfs_refcount_count(&tab->sa_refcount));
1134                         sa_idx_tab_rele(os, tab);
1135                 }
1136         }
1137 
1138         cookie = NULL;
1139         while (layout = avl_destroy_nodes(&sa->sa_layout_num_tree, &cookie)) {
1140                 kmem_free(layout->lot_attrs,
1141                     sizeof (sa_attr_type_t) * layout->lot_attr_count);
1142                 kmem_free(layout, sizeof (sa_lot_t));
1143         }
1144 
1145         avl_destroy(&sa->sa_layout_hash_tree);
1146         avl_destroy(&sa->sa_layout_num_tree);
1147         mutex_destroy(&sa->sa_lock);
1148 
1149         kmem_free(sa, sizeof (sa_os_t));
1150         os->os_sa = NULL;
1151 }
1152 
1153 void
1154 sa_build_idx_tab(void *hdr, void *attr_addr, sa_attr_type_t attr,
1155     uint16_t length, int length_idx, boolean_t var_length, void *userp)
1156 {
1157         sa_idx_tab_t *idx_tab = userp;
1158 
1159         if (var_length) {
1160                 ASSERT(idx_tab->sa_variable_lengths);
1161                 idx_tab->sa_variable_lengths[length_idx] = length;
1162         }
1163         TOC_ATTR_ENCODE(idx_tab->sa_idx_tab[attr], length_idx,
1164             (uint32_t)((uintptr_t)attr_addr - (uintptr_t)hdr));
1165 }
1166 
1167 static void
1168 sa_attr_iter(objset_t *os, sa_hdr_phys_t *hdr, dmu_object_type_t type,
1169     sa_iterfunc_t func, sa_lot_t *tab, void *userp)
1170 {
1171         void *data_start;
1172         sa_lot_t *tb = tab;
1173         sa_lot_t search;
1174         avl_index_t loc;
1175         sa_os_t *sa = os->os_sa;
1176         int i;
1177         uint16_t *length_start = NULL;
1178         uint8_t length_idx = 0;
1179 
1180         if (tab == NULL) {
1181                 search.lot_num = SA_LAYOUT_NUM(hdr, type);
1182                 tb = avl_find(&sa->sa_layout_num_tree, &search, &loc);
1183                 ASSERT(tb);
1184         }
1185 
1186         if (IS_SA_BONUSTYPE(type)) {
1187                 data_start = (void *)P2ROUNDUP(((uintptr_t)hdr +
1188                     offsetof(sa_hdr_phys_t, sa_lengths) +
1189                     (sizeof (uint16_t) * tb->lot_var_sizes)), 8);
1190                 length_start = hdr->sa_lengths;
1191         } else {
1192                 data_start = hdr;
1193         }
1194 
1195         for (i = 0; i != tb->lot_attr_count; i++) {
1196                 int attr_length, reg_length;
1197                 uint8_t idx_len;
1198 
1199                 reg_length = sa->sa_attr_table[tb->lot_attrs[i]].sa_length;
1200                 if (reg_length) {
1201                         attr_length = reg_length;
1202                         idx_len = 0;
1203                 } else {
1204                         attr_length = length_start[length_idx];
1205                         idx_len = length_idx++;
1206                 }
1207 
1208                 func(hdr, data_start, tb->lot_attrs[i], attr_length,
1209                     idx_len, reg_length == 0 ? B_TRUE : B_FALSE, userp);
1210 
1211                 data_start = (void *)P2ROUNDUP(((uintptr_t)data_start +
1212                     attr_length), 8);
1213         }
1214 }
1215 
1216 /*ARGSUSED*/
1217 void
1218 sa_byteswap_cb(void *hdr, void *attr_addr, sa_attr_type_t attr,
1219     uint16_t length, int length_idx, boolean_t variable_length, void *userp)
1220 {
1221         sa_handle_t *hdl = userp;
1222         sa_os_t *sa = hdl->sa_os->os_sa;
1223 
1224         sa_bswap_table[sa->sa_attr_table[attr].sa_byteswap](attr_addr, length);
1225 }
1226 
1227 void
1228 sa_byteswap(sa_handle_t *hdl, sa_buf_type_t buftype)
1229 {
1230         sa_hdr_phys_t *sa_hdr_phys = SA_GET_HDR(hdl, buftype);
1231         dmu_buf_impl_t *db;
1232         sa_os_t *sa = hdl->sa_os->os_sa;
1233         int num_lengths = 1;
1234         int i;
1235 
1236         ASSERT(MUTEX_HELD(&sa->sa_lock));
1237         if (sa_hdr_phys->sa_magic == SA_MAGIC)
1238                 return;
1239 
1240         db = SA_GET_DB(hdl, buftype);
1241 
1242         if (buftype == SA_SPILL) {
1243                 arc_release(db->db_buf, NULL);
1244                 arc_buf_thaw(db->db_buf);
1245         }
1246 
1247         sa_hdr_phys->sa_magic = BSWAP_32(sa_hdr_phys->sa_magic);
1248         sa_hdr_phys->sa_layout_info = BSWAP_16(sa_hdr_phys->sa_layout_info);
1249 
1250         /*
1251          * Determine number of variable lenghts in header
1252          * The standard 8 byte header has one for free and a
1253          * 16 byte header would have 4 + 1;
1254          */
1255         if (SA_HDR_SIZE(sa_hdr_phys) > 8)
1256                 num_lengths += (SA_HDR_SIZE(sa_hdr_phys) - 8) >> 1;
1257         for (i = 0; i != num_lengths; i++)
1258                 sa_hdr_phys->sa_lengths[i] =
1259                     BSWAP_16(sa_hdr_phys->sa_lengths[i]);
1260 
1261         sa_attr_iter(hdl->sa_os, sa_hdr_phys, DMU_OT_SA,
1262             sa_byteswap_cb, NULL, hdl);
1263 
1264         if (buftype == SA_SPILL)
1265                 arc_buf_freeze(((dmu_buf_impl_t *)hdl->sa_spill)->db_buf);
1266 }
1267 
1268 static int
1269 sa_build_index(sa_handle_t *hdl, sa_buf_type_t buftype)
1270 {
1271         sa_hdr_phys_t *sa_hdr_phys;
1272         dmu_buf_impl_t *db = SA_GET_DB(hdl, buftype);
1273         dmu_object_type_t bonustype = SA_BONUSTYPE_FROM_DB(db);
1274         sa_os_t *sa = hdl->sa_os->os_sa;
1275         sa_idx_tab_t *idx_tab;
1276 
1277         sa_hdr_phys = SA_GET_HDR(hdl, buftype);
1278 
1279         mutex_enter(&sa->sa_lock);
1280 
1281         /* Do we need to byteswap? */
1282 
1283         /* only check if not old znode */
1284         if (IS_SA_BONUSTYPE(bonustype) && sa_hdr_phys->sa_magic != SA_MAGIC &&
1285             sa_hdr_phys->sa_magic != 0) {
1286                 VERIFY(BSWAP_32(sa_hdr_phys->sa_magic) == SA_MAGIC);
1287                 sa_byteswap(hdl, buftype);
1288         }
1289 
1290         idx_tab = sa_find_idx_tab(hdl->sa_os, bonustype, sa_hdr_phys);
1291 
1292         if (buftype == SA_BONUS)
1293                 hdl->sa_bonus_tab = idx_tab;
1294         else
1295                 hdl->sa_spill_tab = idx_tab;
1296 
1297         mutex_exit(&sa->sa_lock);
1298         return (0);
1299 }
1300 
1301 /*ARGSUSED*/
1302 static void
1303 sa_evict_sync(void *dbu)
1304 {
1305         panic("evicting sa dbuf\n");
1306 }
1307 
1308 static void
1309 sa_idx_tab_rele(objset_t *os, void *arg)
1310 {
1311         sa_os_t *sa = os->os_sa;
1312         sa_idx_tab_t *idx_tab = arg;
1313 
1314         if (idx_tab == NULL)
1315                 return;
1316 
1317         mutex_enter(&sa->sa_lock);
1318         if (zfs_refcount_remove(&idx_tab->sa_refcount, NULL) == 0) {
1319                 list_remove(&idx_tab->sa_layout->lot_idx_tab, idx_tab);
1320                 if (idx_tab->sa_variable_lengths)
1321                         kmem_free(idx_tab->sa_variable_lengths,
1322                             sizeof (uint16_t) *
1323                             idx_tab->sa_layout->lot_var_sizes);
1324                 zfs_refcount_destroy(&idx_tab->sa_refcount);
1325                 kmem_free(idx_tab->sa_idx_tab,
1326                     sizeof (uint32_t) * sa->sa_num_attrs);
1327                 kmem_free(idx_tab, sizeof (sa_idx_tab_t));
1328         }
1329         mutex_exit(&sa->sa_lock);
1330 }
1331 
1332 static void
1333 sa_idx_tab_hold(objset_t *os, sa_idx_tab_t *idx_tab)
1334 {
1335         sa_os_t *sa = os->os_sa;
1336 
1337         ASSERT(MUTEX_HELD(&sa->sa_lock));
1338         (void) zfs_refcount_add(&idx_tab->sa_refcount, NULL);
1339 }
1340 
1341 void
1342 sa_handle_destroy(sa_handle_t *hdl)
1343 {
1344         dmu_buf_t *db = hdl->sa_bonus;
1345 
1346         mutex_enter(&hdl->sa_lock);
1347         (void) dmu_buf_remove_user(db, &hdl->sa_dbu);
1348 
1349         if (hdl->sa_bonus_tab)
1350                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_bonus_tab);
1351 
1352         if (hdl->sa_spill_tab)
1353                 sa_idx_tab_rele(hdl->sa_os, hdl->sa_spill_tab);
1354 
1355         dmu_buf_rele(hdl->sa_bonus, NULL);
1356 
1357         if (hdl->sa_spill)
1358                 dmu_buf_rele((dmu_buf_t *)hdl->sa_spill, NULL);
1359         mutex_exit(&hdl->sa_lock);
1360 
1361         kmem_cache_free(sa_cache, hdl);
1362 }
1363 
1364 int
1365 sa_handle_get_from_db(objset_t *os, dmu_buf_t *db, void *userp,
1366     sa_handle_type_t hdl_type, sa_handle_t **handlepp)
1367 {
1368         int error = 0;
1369         dmu_object_info_t doi;
1370         sa_handle_t *handle = NULL;
1371 
1372 #ifdef ZFS_DEBUG
1373         dmu_object_info_from_db(db, &doi);
1374         ASSERT(doi.doi_bonus_type == DMU_OT_SA ||
1375             doi.doi_bonus_type == DMU_OT_ZNODE);
1376 #endif
1377         /* find handle, if it exists */
1378         /* if one doesn't exist then create a new one, and initialize it */
1379 
1380         if (hdl_type == SA_HDL_SHARED)
1381                 handle = dmu_buf_get_user(db);
1382 
1383         if (handle == NULL) {
1384                 sa_handle_t *winner = NULL;
1385 
1386                 handle = kmem_cache_alloc(sa_cache, KM_SLEEP);
1387                 handle->sa_dbu.dbu_evict_func_sync = NULL;
1388                 handle->sa_dbu.dbu_evict_func_async = NULL;
1389                 handle->sa_userp = userp;
1390                 handle->sa_bonus = db;
1391                 handle->sa_os = os;
1392                 handle->sa_spill = NULL;
1393                 handle->sa_bonus_tab = NULL;
1394                 handle->sa_spill_tab = NULL;
1395 
1396                 error = sa_build_index(handle, SA_BONUS);
1397 
1398                 if (hdl_type == SA_HDL_SHARED) {
1399                         dmu_buf_init_user(&handle->sa_dbu, sa_evict_sync, NULL,
1400                             NULL);
1401                         winner = dmu_buf_set_user_ie(db, &handle->sa_dbu);
1402                 }
1403 
1404                 if (winner != NULL) {
1405                         kmem_cache_free(sa_cache, handle);
1406                         handle = winner;
1407                 }
1408         }
1409         *handlepp = handle;
1410 
1411         return (error);
1412 }
1413 
1414 int
1415 sa_handle_get(objset_t *objset, uint64_t objid, void *userp,
1416     sa_handle_type_t hdl_type, sa_handle_t **handlepp)
1417 {
1418         dmu_buf_t *db;
1419         int error;
1420 
1421         if (error = dmu_bonus_hold(objset, objid, NULL, &db))
1422                 return (error);
1423 
1424         return (sa_handle_get_from_db(objset, db, userp, hdl_type,
1425             handlepp));
1426 }
1427 
1428 int
1429 sa_buf_hold(objset_t *objset, uint64_t obj_num, void *tag, dmu_buf_t **db)
1430 {
1431         return (dmu_bonus_hold(objset, obj_num, tag, db));
1432 }
1433 
1434 void
1435 sa_buf_rele(dmu_buf_t *db, void *tag)
1436 {
1437         dmu_buf_rele(db, tag);
1438 }
1439 
1440 int
1441 sa_lookup_impl(sa_handle_t *hdl, sa_bulk_attr_t *bulk, int count)
1442 {
1443         ASSERT(hdl);
1444         ASSERT(MUTEX_HELD(&hdl->sa_lock));
1445         return (sa_attr_op(hdl, bulk, count, SA_LOOKUP, NULL));
1446 }
1447 
1448 static int
1449 sa_lookup_locked(sa_handle_t *hdl, sa_attr_type_t attr, void *buf,
1450     uint32_t buflen)
1451 {
1452         int error;
1453         sa_bulk_attr_t bulk;
1454 
1455         bulk.sa_attr = attr;
1456         bulk.sa_data = buf;
1457         bulk.sa_length = buflen;
1458         bulk.sa_data_func = NULL;
1459 
1460         ASSERT(hdl);
1461         error = sa_lookup_impl(hdl, &bulk, 1);
1462         return (error);
1463 }
1464 
1465 int
1466 sa_lookup(sa_handle_t *hdl, sa_attr_type_t attr, void *buf, uint32_t buflen)
1467 {
1468         int error;
1469 
1470         mutex_enter(&hdl->sa_lock);
1471         error = sa_lookup_locked(hdl, attr, buf, buflen);
1472         mutex_exit(&hdl->sa_lock);
1473 
1474         return (error);
1475 }
1476 
1477 #ifdef _KERNEL
1478 int
1479 sa_lookup_uio(sa_handle_t *hdl, sa_attr_type_t attr, uio_t *uio)
1480 {
1481         int error;
1482         sa_bulk_attr_t bulk;
1483 
1484         bulk.sa_data = NULL;
1485         bulk.sa_attr = attr;
1486         bulk.sa_data_func = NULL;
1487 
1488         ASSERT(hdl);
1489 
1490         mutex_enter(&hdl->sa_lock);
1491         if ((error = sa_attr_op(hdl, &bulk, 1, SA_LOOKUP, NULL)) == 0) {
1492                 error = uiomove((void *)bulk.sa_addr, MIN(bulk.sa_size,
1493                     uio->uio_resid), UIO_READ, uio);
1494         }
1495         mutex_exit(&hdl->sa_lock);
1496         return (error);
1497 
1498 }
1499 
1500 /*
1501  * For the existing object that is upgraded from old system, its ondisk layout
1502  * has no slot for the project ID attribute. But quota accounting logic needs
1503  * to access related slots by offset directly. So we need to adjust these old
1504  * objects' layout to make the project ID to some unified and fixed offset.
1505  */
1506 int
1507 sa_add_projid(sa_handle_t *hdl, dmu_tx_t *tx, uint64_t projid)
1508 {
1509         znode_t *zp = sa_get_userdata(hdl);
1510         dmu_buf_t *db = sa_get_db(hdl);
1511         zfsvfs_t *zfsvfs = zp->z_zfsvfs;
1512         int count = 0, err = 0;
1513         sa_bulk_attr_t *bulk, *attrs;
1514         zfs_acl_locator_cb_t locate = { 0 };
1515         uint64_t uid, gid, mode, rdev, xattr = 0, parent, gen, links;
1516         uint64_t crtime[2], mtime[2], ctime[2], atime[2];
1517         zfs_acl_phys_t znode_acl = { 0 };
1518         char scanstamp[AV_SCANSTAMP_SZ];
1519 
1520         if (zp->z_acl_cached == NULL) {
1521                 zfs_acl_t *aclp;
1522 
1523                 mutex_enter(&zp->z_acl_lock);
1524                 err = zfs_acl_node_read(zp, B_FALSE, &aclp, B_FALSE);
1525                 mutex_exit(&zp->z_acl_lock);
1526                 if (err != 0 && err != ENOENT)
1527                         return (err);
1528         }
1529 
1530         bulk = kmem_zalloc(sizeof (sa_bulk_attr_t) * ZPL_END, KM_SLEEP);
1531         attrs = kmem_zalloc(sizeof (sa_bulk_attr_t) * ZPL_END, KM_SLEEP);
1532         mutex_enter(&hdl->sa_lock);
1533         mutex_enter(&zp->z_lock);
1534 
1535         err = sa_lookup_locked(hdl, SA_ZPL_PROJID(zfsvfs), &projid,
1536             sizeof (uint64_t));
1537         if (unlikely(err == 0))
1538                 /* Someone has added project ID attr by race. */
1539                 err = EEXIST;
1540         if (err != ENOENT)
1541                 goto out;
1542 
1543         /* First do a bulk query of the attributes that aren't cached */
1544         if (zp->z_is_sa) {
1545                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs), NULL,
1546                     &mode, 8);
1547                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GEN(zfsvfs), NULL,
1548                     &gen, 8);
1549                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL,
1550                     &uid, 8);
1551                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs), NULL,
1552                     &gid, 8);
1553                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL,
1554                     &parent, 8);
1555                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ATIME(zfsvfs), NULL,
1556                     &atime, 16);
1557                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
1558                     &mtime, 16);
1559                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
1560                     &ctime, 16);
1561                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CRTIME(zfsvfs), NULL,
1562                     &crtime, 16);
1563                 if (S_ISBLK(zp->z_mode) || S_ISCHR(zp->z_mode))
1564                         SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_RDEV(zfsvfs), NULL,
1565                             &rdev, 8);
1566         } else {
1567                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ATIME(zfsvfs), NULL,
1568                     &atime, 16);
1569                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
1570                     &mtime, 16);
1571                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
1572                     &ctime, 16);
1573                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CRTIME(zfsvfs), NULL,
1574                     &crtime, 16);
1575                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GEN(zfsvfs), NULL,
1576                     &gen, 8);
1577                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs), NULL,
1578                     &mode, 8);
1579                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL,
1580                     &parent, 8);
1581                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_XATTR(zfsvfs), NULL,
1582                     &xattr, 8);
1583                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_RDEV(zfsvfs), NULL,
1584                     &rdev, 8);
1585                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL,
1586                     &uid, 8);
1587                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs), NULL,
1588                     &gid, 8);
1589                 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ZNODE_ACL(zfsvfs), NULL,
1590                     &znode_acl, 88);
1591         }
1592         err = sa_bulk_lookup_locked(hdl, bulk, count);
1593         if (err != 0)
1594                 goto out;
1595 
1596         err = sa_lookup_locked(hdl, SA_ZPL_XATTR(zfsvfs), &xattr, 8);
1597         if (err != 0 && err != ENOENT)
1598                 goto out;
1599 
1600         zp->z_projid = projid;
1601         zp->z_pflags |= ZFS_PROJID;
1602         links = zp->z_links;
1603         count = 0;
1604         err = 0;
1605 
1606         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_MODE(zfsvfs), NULL, &mode, 8);
1607         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_SIZE(zfsvfs), NULL,
1608             &zp->z_size, 8);
1609         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_GEN(zfsvfs), NULL, &gen, 8);
1610         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_UID(zfsvfs), NULL, &uid, 8);
1611         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_GID(zfsvfs), NULL, &gid, 8);
1612         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_PARENT(zfsvfs), NULL, &parent, 8);
1613         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_FLAGS(zfsvfs), NULL,
1614             &zp->z_pflags, 8);
1615         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_ATIME(zfsvfs), NULL, &atime, 16);
1616         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_MTIME(zfsvfs), NULL, &mtime, 16);
1617         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_CTIME(zfsvfs), NULL, &ctime, 16);
1618         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_CRTIME(zfsvfs), NULL,
1619             &crtime, 16);
1620         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_LINKS(zfsvfs), NULL, &links, 8);
1621         SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_PROJID(zfsvfs), NULL, &projid, 8);
1622 
1623         if (S_ISBLK(zp->z_mode) || S_ISCHR(zp->z_mode))
1624                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_RDEV(zfsvfs), NULL,
1625                     &rdev, 8);
1626 
1627         if (zp->z_acl_cached != NULL) {
1628                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_DACL_COUNT(zfsvfs), NULL,
1629                     &zp->z_acl_cached->z_acl_count, 8);
1630                 if (zp->z_acl_cached->z_version < ZFS_ACL_VERSION_FUID)
1631                         zfs_acl_xform(zp, zp->z_acl_cached, CRED());
1632                 locate.cb_aclp = zp->z_acl_cached;
1633                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_DACL_ACES(zfsvfs),
1634                     zfs_acl_data_locator, &locate,
1635                     zp->z_acl_cached->z_acl_bytes);
1636         }
1637 
1638         if (xattr)
1639                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_XATTR(zfsvfs), NULL,
1640                     &xattr, 8);
1641 
1642         if (zp->z_pflags & ZFS_BONUS_SCANSTAMP) {
1643                 bcopy((caddr_t)db->db_data + ZFS_OLD_ZNODE_PHYS_SIZE,
1644                     scanstamp, AV_SCANSTAMP_SZ);
1645                 SA_ADD_BULK_ATTR(attrs, count, SA_ZPL_SCANSTAMP(zfsvfs), NULL,
1646                     scanstamp, AV_SCANSTAMP_SZ);
1647                 zp->z_pflags &= ~ZFS_BONUS_SCANSTAMP;
1648         }
1649 
1650         VERIFY(dmu_set_bonustype(db, DMU_OT_SA, tx) == 0);
1651         VERIFY(sa_replace_all_by_template_locked(hdl, attrs, count, tx) == 0);
1652         if (znode_acl.z_acl_extern_obj) {
1653                 VERIFY(0 == dmu_object_free(zfsvfs->z_os,
1654                     znode_acl.z_acl_extern_obj, tx));
1655         }
1656 
1657         zp->z_is_sa = B_TRUE;
1658 
1659 out:
1660         mutex_exit(&zp->z_lock);
1661         mutex_exit(&hdl->sa_lock);
1662         kmem_free(attrs, sizeof (sa_bulk_attr_t) * ZPL_END);
1663         kmem_free(bulk, sizeof (sa_bulk_attr_t) * ZPL_END);
1664         return (err);
1665 }
1666 #endif
1667 
1668 static sa_idx_tab_t *
1669 sa_find_idx_tab(objset_t *os, dmu_object_type_t bonustype, sa_hdr_phys_t *hdr)
1670 {
1671         sa_idx_tab_t *idx_tab;
1672         sa_os_t *sa = os->os_sa;
1673         sa_lot_t *tb, search;
1674         avl_index_t loc;
1675 
1676         /*
1677          * Deterimine layout number.  If SA node and header == 0 then
1678          * force the index table to the dummy "1" empty layout.
1679          *
1680          * The layout number would only be zero for a newly created file
1681          * that has not added any attributes yet, or with crypto enabled which
1682          * doesn't write any attributes to the bonus buffer.
1683          */
1684 
1685         search.lot_num = SA_LAYOUT_NUM(hdr, bonustype);
1686 
1687         tb = avl_find(&sa->sa_layout_num_tree, &search, &loc);
1688 
1689         /* Verify header size is consistent with layout information */
1690         ASSERT(tb);
1691         ASSERT(IS_SA_BONUSTYPE(bonustype) &&
1692             SA_HDR_SIZE_MATCH_LAYOUT(hdr, tb) || !IS_SA_BONUSTYPE(bonustype) ||
1693             (IS_SA_BONUSTYPE(bonustype) && hdr->sa_layout_info == 0));
1694 
1695         /*
1696          * See if any of the already existing TOC entries can be reused?
1697          */
1698 
1699         for (idx_tab = list_head(&tb->lot_idx_tab); idx_tab;
1700             idx_tab = list_next(&tb->lot_idx_tab, idx_tab)) {
1701                 boolean_t valid_idx = B_TRUE;
1702                 int i;
1703 
1704                 if (tb->lot_var_sizes != 0 &&
1705                     idx_tab->sa_variable_lengths != NULL) {
1706                         for (i = 0; i != tb->lot_var_sizes; i++) {
1707                                 if (hdr->sa_lengths[i] !=
1708                                     idx_tab->sa_variable_lengths[i]) {
1709                                         valid_idx = B_FALSE;
1710                                         break;
1711                                 }
1712                         }
1713                 }
1714                 if (valid_idx) {
1715                         sa_idx_tab_hold(os, idx_tab);
1716                         return (idx_tab);
1717                 }
1718         }
1719 
1720         /* No such luck, create a new entry */
1721         idx_tab = kmem_zalloc(sizeof (sa_idx_tab_t), KM_SLEEP);
1722         idx_tab->sa_idx_tab =
1723             kmem_zalloc(sizeof (uint32_t) * sa->sa_num_attrs, KM_SLEEP);
1724         idx_tab->sa_layout = tb;
1725         zfs_refcount_create(&idx_tab->sa_refcount);
1726         if (tb->lot_var_sizes)
1727                 idx_tab->sa_variable_lengths = kmem_alloc(sizeof (uint16_t) *
1728                     tb->lot_var_sizes, KM_SLEEP);
1729 
1730         sa_attr_iter(os, hdr, bonustype, sa_build_idx_tab,
1731             tb, idx_tab);
1732         sa_idx_tab_hold(os, idx_tab);   /* one hold for consumer */
1733         sa_idx_tab_hold(os, idx_tab);   /* one for layout */
1734         list_insert_tail(&tb->lot_idx_tab, idx_tab);
1735         return (idx_tab);
1736 }
1737 
1738 void
1739 sa_default_locator(void **dataptr, uint32_t *len, uint32_t total_len,
1740     boolean_t start, void *userdata)
1741 {
1742         ASSERT(start);
1743 
1744         *dataptr = userdata;
1745         *len = total_len;
1746 }
1747 
1748 static void
1749 sa_attr_register_sync(sa_handle_t *hdl, dmu_tx_t *tx)
1750 {
1751         uint64_t attr_value = 0;
1752         sa_os_t *sa = hdl->sa_os->os_sa;
1753         sa_attr_table_t *tb = sa->sa_attr_table;
1754         int i;
1755 
1756         mutex_enter(&sa->sa_lock);
1757 
1758         if (!sa->sa_need_attr_registration || sa->sa_master_obj == 0) {
1759                 mutex_exit(&sa->sa_lock);
1760                 return;
1761         }
1762 
1763         if (sa->sa_reg_attr_obj == 0) {
1764                 sa->sa_reg_attr_obj = zap_create_link(hdl->sa_os,
1765                     DMU_OT_SA_ATTR_REGISTRATION,
1766                     sa->sa_master_obj, SA_REGISTRY, tx);
1767         }
1768         for (i = 0; i != sa->sa_num_attrs; i++) {
1769                 if (sa->sa_attr_table[i].sa_registered)
1770                         continue;
1771                 ATTR_ENCODE(attr_value, tb[i].sa_attr, tb[i].sa_length,
1772                     tb[i].sa_byteswap);
1773                 VERIFY(0 == zap_update(hdl->sa_os, sa->sa_reg_attr_obj,
1774                     tb[i].sa_name, 8, 1, &attr_value, tx));
1775                 tb[i].sa_registered = B_TRUE;
1776         }
1777         sa->sa_need_attr_registration = B_FALSE;
1778         mutex_exit(&sa->sa_lock);
1779 }
1780 
1781 /*
1782  * Replace all attributes with attributes specified in template.
1783  * If dnode had a spill buffer then those attributes will be
1784  * also be replaced, possibly with just an empty spill block
1785  *
1786  * This interface is intended to only be used for bulk adding of
1787  * attributes for a new file.  It will also be used by the ZPL
1788  * when converting and old formatted znode to native SA support.
1789  */
1790 int
1791 sa_replace_all_by_template_locked(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc,
1792     int attr_count, dmu_tx_t *tx)
1793 {
1794         sa_os_t *sa = hdl->sa_os->os_sa;
1795 
1796         if (sa->sa_need_attr_registration)
1797                 sa_attr_register_sync(hdl, tx);
1798         return (sa_build_layouts(hdl, attr_desc, attr_count, tx));
1799 }
1800 
1801 int
1802 sa_replace_all_by_template(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc,
1803     int attr_count, dmu_tx_t *tx)
1804 {
1805         int error;
1806 
1807         mutex_enter(&hdl->sa_lock);
1808         error = sa_replace_all_by_template_locked(hdl, attr_desc,
1809             attr_count, tx);
1810         mutex_exit(&hdl->sa_lock);
1811         return (error);
1812 }
1813 
1814 /*
1815  * Add/remove a single attribute or replace a variable-sized attribute value
1816  * with a value of a different size, and then rewrite the entire set
1817  * of attributes.
1818  * Same-length attribute value replacement (including fixed-length attributes)
1819  * is handled more efficiently by the upper layers.
1820  */
1821 static int
1822 sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr,
1823     sa_data_op_t action, sa_data_locator_t *locator, void *datastart,
1824     uint16_t buflen, dmu_tx_t *tx)
1825 {
1826         sa_os_t *sa = hdl->sa_os->os_sa;
1827         dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus;
1828         dnode_t *dn;
1829         sa_bulk_attr_t *attr_desc;
1830         void *old_data[2];
1831         int bonus_attr_count = 0;
1832         int bonus_data_size = 0;
1833         int spill_data_size = 0;
1834         int spill_attr_count = 0;
1835         int error;
1836         uint16_t length, reg_length;
1837         int i, j, k, length_idx;
1838         sa_hdr_phys_t *hdr;
1839         sa_idx_tab_t *idx_tab;
1840         int attr_count;
1841         int count;
1842 
1843         ASSERT(MUTEX_HELD(&hdl->sa_lock));
1844 
1845         /* First make of copy of the old data */
1846 
1847         DB_DNODE_ENTER(db);
1848         dn = DB_DNODE(db);
1849         if (dn->dn_bonuslen != 0) {
1850                 bonus_data_size = hdl->sa_bonus->db_size;
1851                 old_data[0] = kmem_alloc(bonus_data_size, KM_SLEEP);
1852                 bcopy(hdl->sa_bonus->db_data, old_data[0],
1853                     hdl->sa_bonus->db_size);
1854                 bonus_attr_count = hdl->sa_bonus_tab->sa_layout->lot_attr_count;
1855         } else {
1856                 old_data[0] = NULL;
1857         }
1858         DB_DNODE_EXIT(db);
1859 
1860         /* Bring spill buffer online if it isn't currently */
1861 
1862         if ((error = sa_get_spill(hdl)) == 0) {
1863                 spill_data_size = hdl->sa_spill->db_size;
1864                 old_data[1] = kmem_alloc(spill_data_size, KM_SLEEP);
1865                 bcopy(hdl->sa_spill->db_data, old_data[1],
1866                     hdl->sa_spill->db_size);
1867                 spill_attr_count =
1868                     hdl->sa_spill_tab->sa_layout->lot_attr_count;
1869         } else if (error && error != ENOENT) {
1870                 if (old_data[0])
1871                         kmem_free(old_data[0], bonus_data_size);
1872                 return (error);
1873         } else {
1874                 old_data[1] = NULL;
1875         }
1876 
1877         /* build descriptor of all attributes */
1878 
1879         attr_count = bonus_attr_count + spill_attr_count;
1880         if (action == SA_ADD)
1881                 attr_count++;
1882         else if (action == SA_REMOVE)
1883                 attr_count--;
1884 
1885         attr_desc = kmem_zalloc(sizeof (sa_bulk_attr_t) * attr_count, KM_SLEEP);
1886 
1887         /*
1888          * loop through bonus and spill buffer if it exists, and
1889          * build up new attr_descriptor to reset the attributes
1890          */
1891         k = j = 0;
1892         count = bonus_attr_count;
1893         hdr = SA_GET_HDR(hdl, SA_BONUS);
1894         idx_tab = SA_IDX_TAB_GET(hdl, SA_BONUS);
1895         for (; k != 2; k++) {
1896                 /*
1897                  * Iterate over each attribute in layout.  Fetch the
1898                  * size of variable-length attributes needing rewrite
1899                  * from sa_lengths[].
1900                  */
1901                 for (i = 0, length_idx = 0; i != count; i++) {
1902                         sa_attr_type_t attr;
1903 
1904                         attr = idx_tab->sa_layout->lot_attrs[i];
1905                         reg_length = SA_REGISTERED_LEN(sa, attr);
1906                         if (reg_length == 0) {
1907                                 length = hdr->sa_lengths[length_idx];
1908                                 length_idx++;
1909                         } else {
1910                                 length = reg_length;
1911                         }
1912                         if (attr == newattr) {
1913                                 /*
1914                                  * There is nothing to do for SA_REMOVE,
1915                                  * so it is just skipped.
1916                                  */
1917                                 if (action == SA_REMOVE)
1918                                         continue;
1919 
1920                                 /*
1921                                  * Duplicate attributes are not allowed, so the
1922                                  * action can not be SA_ADD here.
1923                                  */
1924                                 ASSERT3S(action, ==, SA_REPLACE);
1925 
1926                                 /*
1927                                  * Only a variable-sized attribute can be
1928                                  * replaced here, and its size must be changing.
1929                                  */
1930                                 ASSERT3U(reg_length, ==, 0);
1931                                 ASSERT3U(length, !=, buflen);
1932                                 SA_ADD_BULK_ATTR(attr_desc, j, attr,
1933                                     locator, datastart, buflen);
1934                         } else {
1935                                 SA_ADD_BULK_ATTR(attr_desc, j, attr,
1936                                     NULL, (void *)
1937                                     (TOC_OFF(idx_tab->sa_idx_tab[attr]) +
1938                                     (uintptr_t)old_data[k]), length);
1939                         }
1940                 }
1941                 if (k == 0 && hdl->sa_spill) {
1942                         hdr = SA_GET_HDR(hdl, SA_SPILL);
1943                         idx_tab = SA_IDX_TAB_GET(hdl, SA_SPILL);
1944                         count = spill_attr_count;
1945                 } else {
1946                         break;
1947                 }
1948         }
1949         if (action == SA_ADD) {
1950                 reg_length = SA_REGISTERED_LEN(sa, newattr);
1951                 IMPLY(reg_length != 0, reg_length == buflen);
1952                 SA_ADD_BULK_ATTR(attr_desc, j, newattr, locator,
1953                     datastart, buflen);
1954         }
1955         ASSERT3U(j, ==, attr_count);
1956 
1957         error = sa_build_layouts(hdl, attr_desc, attr_count, tx);
1958 
1959         if (old_data[0])
1960                 kmem_free(old_data[0], bonus_data_size);
1961         if (old_data[1])
1962                 kmem_free(old_data[1], spill_data_size);
1963         kmem_free(attr_desc, sizeof (sa_bulk_attr_t) * attr_count);
1964 
1965         return (error);
1966 }
1967 
1968 static int
1969 sa_bulk_update_impl(sa_handle_t *hdl, sa_bulk_attr_t *bulk, int count,
1970     dmu_tx_t *tx)
1971 {
1972         int error;
1973         sa_os_t *sa = hdl->sa_os->os_sa;
1974         dmu_object_type_t bonustype;
1975 
1976         bonustype = SA_BONUSTYPE_FROM_DB(SA_GET_DB(hdl, SA_BONUS));
1977 
1978         ASSERT(hdl);
1979         ASSERT(MUTEX_HELD(&hdl->sa_lock));
1980 
1981         /* sync out registration table if necessary */
1982         if (sa->sa_need_attr_registration)
1983                 sa_attr_register_sync(hdl, tx);
1984 
1985         error = sa_attr_op(hdl, bulk, count, SA_UPDATE, tx);
1986         if (error == 0 && !IS_SA_BONUSTYPE(bonustype) && sa->sa_update_cb)
1987                 sa->sa_update_cb(hdl, tx);
1988 
1989         return (error);
1990 }
1991 
1992 /*
1993  * update or add new attribute
1994  */
1995 int
1996 sa_update(sa_handle_t *hdl, sa_attr_type_t type,
1997     void *buf, uint32_t buflen, dmu_tx_t *tx)
1998 {
1999         int error;
2000         sa_bulk_attr_t bulk;
2001 
2002         bulk.sa_attr = type;
2003         bulk.sa_data_func = NULL;
2004         bulk.sa_length = buflen;
2005         bulk.sa_data = buf;
2006 
2007         mutex_enter(&hdl->sa_lock);
2008         error = sa_bulk_update_impl(hdl, &bulk, 1, tx);
2009         mutex_exit(&hdl->sa_lock);
2010         return (error);
2011 }
2012 
2013 int
2014 sa_update_from_cb(sa_handle_t *hdl, sa_attr_type_t attr,
2015     uint32_t buflen, sa_data_locator_t *locator, void *userdata, dmu_tx_t *tx)
2016 {
2017         int error;
2018         sa_bulk_attr_t bulk;
2019 
2020         bulk.sa_attr = attr;
2021         bulk.sa_data = userdata;
2022         bulk.sa_data_func = locator;
2023         bulk.sa_length = buflen;
2024 
2025         mutex_enter(&hdl->sa_lock);
2026         error = sa_bulk_update_impl(hdl, &bulk, 1, tx);
2027         mutex_exit(&hdl->sa_lock);
2028         return (error);
2029 }
2030 
2031 /*
2032  * Return size of an attribute
2033  */
2034 
2035 int
2036 sa_size(sa_handle_t *hdl, sa_attr_type_t attr, int *size)
2037 {
2038         sa_bulk_attr_t bulk;
2039         int error;
2040 
2041         bulk.sa_data = NULL;
2042         bulk.sa_attr = attr;
2043         bulk.sa_data_func = NULL;
2044 
2045         ASSERT(hdl);
2046         mutex_enter(&hdl->sa_lock);
2047         if ((error = sa_attr_op(hdl, &bulk, 1, SA_LOOKUP, NULL)) != 0) {
2048                 mutex_exit(&hdl->sa_lock);
2049                 return (error);
2050         }
2051         *size = bulk.sa_size;
2052 
2053         mutex_exit(&hdl->sa_lock);
2054         return (0);
2055 }
2056 
2057 int
2058 sa_bulk_lookup_locked(sa_handle_t *hdl, sa_bulk_attr_t *attrs, int count)
2059 {
2060         ASSERT(hdl);
2061         ASSERT(MUTEX_HELD(&hdl->sa_lock));
2062         return (sa_lookup_impl(hdl, attrs, count));
2063 }
2064 
2065 int
2066 sa_bulk_lookup(sa_handle_t *hdl, sa_bulk_attr_t *attrs, int count)
2067 {
2068         int error;
2069 
2070         ASSERT(hdl);
2071         mutex_enter(&hdl->sa_lock);
2072         error = sa_bulk_lookup_locked(hdl, attrs, count);
2073         mutex_exit(&hdl->sa_lock);
2074         return (error);
2075 }
2076 
2077 int
2078 sa_bulk_update(sa_handle_t *hdl, sa_bulk_attr_t *attrs, int count, dmu_tx_t *tx)
2079 {
2080         int error;
2081 
2082         ASSERT(hdl);
2083         mutex_enter(&hdl->sa_lock);
2084         error = sa_bulk_update_impl(hdl, attrs, count, tx);
2085         mutex_exit(&hdl->sa_lock);
2086         return (error);
2087 }
2088 
2089 int
2090 sa_remove(sa_handle_t *hdl, sa_attr_type_t attr, dmu_tx_t *tx)
2091 {
2092         int error;
2093 
2094         mutex_enter(&hdl->sa_lock);
2095         error = sa_modify_attrs(hdl, attr, SA_REMOVE, NULL,
2096             NULL, 0, tx);
2097         mutex_exit(&hdl->sa_lock);
2098         return (error);
2099 }
2100 
2101 void
2102 sa_object_info(sa_handle_t *hdl, dmu_object_info_t *doi)
2103 {
2104         dmu_object_info_from_db((dmu_buf_t *)hdl->sa_bonus, doi);
2105 }
2106 
2107 void
2108 sa_object_size(sa_handle_t *hdl, uint32_t *blksize, u_longlong_t *nblocks)
2109 {
2110         dmu_object_size_from_db((dmu_buf_t *)hdl->sa_bonus,
2111             blksize, nblocks);
2112 }
2113 
2114 void
2115 sa_set_userp(sa_handle_t *hdl, void *ptr)
2116 {
2117         hdl->sa_userp = ptr;
2118 }
2119 
2120 dmu_buf_t *
2121 sa_get_db(sa_handle_t *hdl)
2122 {
2123         return ((dmu_buf_t *)hdl->sa_bonus);
2124 }
2125 
2126 void *
2127 sa_get_userdata(sa_handle_t *hdl)
2128 {
2129         return (hdl->sa_userp);
2130 }
2131 
2132 void
2133 sa_register_update_callback_locked(objset_t *os, sa_update_cb_t *func)
2134 {
2135         ASSERT(MUTEX_HELD(&os->os_sa->sa_lock));
2136         os->os_sa->sa_update_cb = func;
2137 }
2138 
2139 void
2140 sa_register_update_callback(objset_t *os, sa_update_cb_t *func)
2141 {
2142 
2143         mutex_enter(&os->os_sa->sa_lock);
2144         sa_register_update_callback_locked(os, func);
2145         mutex_exit(&os->os_sa->sa_lock);
2146 }
2147 
2148 uint64_t
2149 sa_handle_object(sa_handle_t *hdl)
2150 {
2151         return (hdl->sa_bonus->db_object);
2152 }
2153 
2154 boolean_t
2155 sa_enabled(objset_t *os)
2156 {
2157         return (os->os_sa == NULL);
2158 }
2159 
2160 int
2161 sa_set_sa_object(objset_t *os, uint64_t sa_object)
2162 {
2163         sa_os_t *sa = os->os_sa;
2164 
2165         if (sa->sa_master_obj)
2166                 return (1);
2167 
2168         sa->sa_master_obj = sa_object;
2169 
2170         return (0);
2171 }
2172 
2173 int
2174 sa_hdrsize(void *arg)
2175 {
2176         sa_hdr_phys_t *hdr = arg;
2177 
2178         return (SA_HDR_SIZE(hdr));
2179 }
2180 
2181 void
2182 sa_handle_lock(sa_handle_t *hdl)
2183 {
2184         ASSERT(hdl);
2185         mutex_enter(&hdl->sa_lock);
2186 }
2187 
2188 void
2189 sa_handle_unlock(sa_handle_t *hdl)
2190 {
2191         ASSERT(hdl);
2192         mutex_exit(&hdl->sa_lock);
2193 }