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