root/fs/ocfs2/uptodate.c

DEFINITIONS

1. ocfs2_metadata_cache_owner
2. ocfs2_metadata_cache_get_super
3. ocfs2_metadata_cache_lock
4. ocfs2_metadata_cache_unlock
5. ocfs2_metadata_cache_io_lock
6. ocfs2_metadata_cache_io_unlock
7. ocfs2_metadata_cache_reset
8. ocfs2_metadata_cache_init
9. ocfs2_metadata_cache_exit
10. ocfs2_purge_copied_metadata_tree
11. ocfs2_metadata_cache_purge
12. ocfs2_search_cache_array
13. ocfs2_search_cache_tree
14. ocfs2_buffer_cached
15. ocfs2_buffer_uptodate
16. ocfs2_buffer_read_ahead
17. ocfs2_append_cache_array
18. __ocfs2_insert_cache_tree
19. ocfs2_insert_can_use_array
20. ocfs2_expand_cache
21. __ocfs2_set_buffer_uptodate
22. ocfs2_set_buffer_uptodate
23. ocfs2_set_new_buffer_uptodate
24. ocfs2_remove_metadata_array
25. ocfs2_remove_metadata_tree
26. ocfs2_remove_block_from_cache
27. ocfs2_remove_from_cache
28. ocfs2_remove_xattr_clusters_from_cache
29. init_ocfs2_uptodate_cache
30. exit_ocfs2_uptodate_cache

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* -*- mode: c; c-basic-offset: 8; -*-
   3  * vim: noexpandtab sw=8 ts=8 sts=0:
   4  *
   5  * uptodate.c
   6  *
   7  * Tracking the up-to-date-ness of a local buffer_head with respect to
   8  * the cluster.
   9  *
  10  * Copyright (C) 2002, 2004, 2005 Oracle.  All rights reserved.
  11  *
  12  * Standard buffer head caching flags (uptodate, etc) are insufficient
  13  * in a clustered environment - a buffer may be marked up to date on
  14  * our local node but could have been modified by another cluster
  15  * member. As a result an additional (and performant) caching scheme
  16  * is required. A further requirement is that we consume as little
  17  * memory as possible - we never pin buffer_head structures in order
  18  * to cache them.
  19  *
  20  * We track the existence of up to date buffers on the inodes which
  21  * are associated with them. Because we don't want to pin
  22  * buffer_heads, this is only a (strong) hint and several other checks
  23  * are made in the I/O path to ensure that we don't use a stale or
  24  * invalid buffer without going to disk:
  25  *      - buffer_jbd is used liberally - if a bh is in the journal on
  26  *        this node then it *must* be up to date.
  27  *      - the standard buffer_uptodate() macro is used to detect buffers
  28  *        which may be invalid (even if we have an up to date tracking
  29  *        item for them)
  30  *
  31  * For a full understanding of how this code works together, one
  32  * should read the callers in dlmglue.c, the I/O functions in
  33  * buffer_head_io.c and ocfs2_journal_access in journal.c
  34  */
  35 
  36 #include <linux/fs.h>
  37 #include <linux/types.h>
  38 #include <linux/slab.h>
  39 #include <linux/highmem.h>
  40 #include <linux/buffer_head.h>
  41 #include <linux/rbtree.h>
  42 
  43 #include <cluster/masklog.h>
  44 
  45 #include "ocfs2.h"
  46 
  47 #include "inode.h"
  48 #include "uptodate.h"
  49 #include "ocfs2_trace.h"
  50 
  51 struct ocfs2_meta_cache_item {
  52         struct rb_node  c_node;
  53         sector_t        c_block;
  54 };
  55 
  56 static struct kmem_cache *ocfs2_uptodate_cachep;
  57 
  58 u64 ocfs2_metadata_cache_owner(struct ocfs2_caching_info *ci)
  59 {
  60         BUG_ON(!ci || !ci->ci_ops);
  61 
  62         return ci->ci_ops->co_owner(ci);
  63 }
  64 
  65 struct super_block *ocfs2_metadata_cache_get_super(struct ocfs2_caching_info *ci)
  66 {
  67         BUG_ON(!ci || !ci->ci_ops);
  68 
  69         return ci->ci_ops->co_get_super(ci);
  70 }
  71 
  72 static void ocfs2_metadata_cache_lock(struct ocfs2_caching_info *ci)
  73 {
  74         BUG_ON(!ci || !ci->ci_ops);
  75 
  76         ci->ci_ops->co_cache_lock(ci);
  77 }
  78 
  79 static void ocfs2_metadata_cache_unlock(struct ocfs2_caching_info *ci)
  80 {
  81         BUG_ON(!ci || !ci->ci_ops);
  82 
  83         ci->ci_ops->co_cache_unlock(ci);
  84 }
  85 
  86 void ocfs2_metadata_cache_io_lock(struct ocfs2_caching_info *ci)
  87 {
  88         BUG_ON(!ci || !ci->ci_ops);
  89 
  90         ci->ci_ops->co_io_lock(ci);
  91 }
  92 
  93 void ocfs2_metadata_cache_io_unlock(struct ocfs2_caching_info *ci)
  94 {
  95         BUG_ON(!ci || !ci->ci_ops);
  96 
  97         ci->ci_ops->co_io_unlock(ci);
  98 }
  99 
 100 
 101 static void ocfs2_metadata_cache_reset(struct ocfs2_caching_info *ci,
 102                                        int clear)
 103 {
 104         ci->ci_flags |= OCFS2_CACHE_FL_INLINE;
 105         ci->ci_num_cached = 0;
 106 
 107         if (clear) {
 108                 ci->ci_created_trans = 0;
 109                 ci->ci_last_trans = 0;
 110         }
 111 }
 112 
 113 void ocfs2_metadata_cache_init(struct ocfs2_caching_info *ci,
 114                                const struct ocfs2_caching_operations *ops)
 115 {
 116         BUG_ON(!ops);
 117 
 118         ci->ci_ops = ops;
 119         ocfs2_metadata_cache_reset(ci, 1);
 120 }
 121 
 122 void ocfs2_metadata_cache_exit(struct ocfs2_caching_info *ci)
 123 {
 124         ocfs2_metadata_cache_purge(ci);
 125         ocfs2_metadata_cache_reset(ci, 1);
 126 }
 127 
 128 
 129 /* No lock taken here as 'root' is not expected to be visible to other
 130  * processes. */
 131 static unsigned int ocfs2_purge_copied_metadata_tree(struct rb_root *root)
 132 {
 133         unsigned int purged = 0;
 134         struct rb_node *node;
 135         struct ocfs2_meta_cache_item *item;
 136 
 137         while ((node = rb_last(root)) != NULL) {
 138                 item = rb_entry(node, struct ocfs2_meta_cache_item, c_node);
 139 
 140                 trace_ocfs2_purge_copied_metadata_tree(
 141                                         (unsigned long long) item->c_block);
 142 
 143                 rb_erase(&item->c_node, root);
 144                 kmem_cache_free(ocfs2_uptodate_cachep, item);
 145 
 146                 purged++;
 147         }
 148         return purged;
 149 }
 150 
 151 /* Called from locking and called from ocfs2_clear_inode. Dump the
 152  * cache for a given inode.
 153  *
 154  * This function is a few more lines longer than necessary due to some
 155  * accounting done here, but I think it's worth tracking down those
 156  * bugs sooner -- Mark */
 157 void ocfs2_metadata_cache_purge(struct ocfs2_caching_info *ci)
 158 {
 159         unsigned int tree, to_purge, purged;
 160         struct rb_root root = RB_ROOT;
 161 
 162         BUG_ON(!ci || !ci->ci_ops);
 163 
 164         ocfs2_metadata_cache_lock(ci);
 165         tree = !(ci->ci_flags & OCFS2_CACHE_FL_INLINE);
 166         to_purge = ci->ci_num_cached;
 167 
 168         trace_ocfs2_metadata_cache_purge(
 169                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 170                 to_purge, tree);
 171 
 172         /* If we're a tree, save off the root so that we can safely
 173          * initialize the cache. We do the work to free tree members
 174          * without the spinlock. */
 175         if (tree)
 176                 root = ci->ci_cache.ci_tree;
 177 
 178         ocfs2_metadata_cache_reset(ci, 0);
 179         ocfs2_metadata_cache_unlock(ci);
 180 
 181         purged = ocfs2_purge_copied_metadata_tree(&root);
 182         /* If possible, track the number wiped so that we can more
 183          * easily detect counting errors. Unfortunately, this is only
 184          * meaningful for trees. */
 185         if (tree && purged != to_purge)
 186                 mlog(ML_ERROR, "Owner %llu, count = %u, purged = %u\n",
 187                      (unsigned long long)ocfs2_metadata_cache_owner(ci),
 188                      to_purge, purged);
 189 }
 190 
 191 /* Returns the index in the cache array, -1 if not found.
 192  * Requires ip_lock. */
 193 static int ocfs2_search_cache_array(struct ocfs2_caching_info *ci,
 194                                     sector_t item)
 195 {
 196         int i;
 197 
 198         for (i = 0; i < ci->ci_num_cached; i++) {
 199                 if (item == ci->ci_cache.ci_array[i])
 200                         return i;
 201         }
 202 
 203         return -1;
 204 }
 205 
 206 /* Returns the cache item if found, otherwise NULL.
 207  * Requires ip_lock. */
 208 static struct ocfs2_meta_cache_item *
 209 ocfs2_search_cache_tree(struct ocfs2_caching_info *ci,
 210                         sector_t block)
 211 {
 212         struct rb_node * n = ci->ci_cache.ci_tree.rb_node;
 213         struct ocfs2_meta_cache_item *item = NULL;
 214 
 215         while (n) {
 216                 item = rb_entry(n, struct ocfs2_meta_cache_item, c_node);
 217 
 218                 if (block < item->c_block)
 219                         n = n->rb_left;
 220                 else if (block > item->c_block)
 221                         n = n->rb_right;
 222                 else
 223                         return item;
 224         }
 225 
 226         return NULL;
 227 }
 228 
 229 static int ocfs2_buffer_cached(struct ocfs2_caching_info *ci,
 230                                struct buffer_head *bh)
 231 {
 232         int index = -1;
 233         struct ocfs2_meta_cache_item *item = NULL;
 234 
 235         ocfs2_metadata_cache_lock(ci);
 236 
 237         trace_ocfs2_buffer_cached_begin(
 238                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 239                 (unsigned long long) bh->b_blocknr,
 240                 !!(ci->ci_flags & OCFS2_CACHE_FL_INLINE));
 241 
 242         if (ci->ci_flags & OCFS2_CACHE_FL_INLINE)
 243                 index = ocfs2_search_cache_array(ci, bh->b_blocknr);
 244         else
 245                 item = ocfs2_search_cache_tree(ci, bh->b_blocknr);
 246 
 247         ocfs2_metadata_cache_unlock(ci);
 248 
 249         trace_ocfs2_buffer_cached_end(index, item);
 250 
 251         return (index != -1) || (item != NULL);
 252 }
 253 
 254 /* Warning: even if it returns true, this does *not* guarantee that
 255  * the block is stored in our inode metadata cache.
 256  *
 257  * This can be called under lock_buffer()
 258  */
 259 int ocfs2_buffer_uptodate(struct ocfs2_caching_info *ci,
 260                           struct buffer_head *bh)
 261 {
 262         /* Doesn't matter if the bh is in our cache or not -- if it's
 263          * not marked uptodate then we know it can't have correct
 264          * data. */
 265         if (!buffer_uptodate(bh))
 266                 return 0;
 267 
 268         /* OCFS2 does not allow multiple nodes to be changing the same
 269          * block at the same time. */
 270         if (buffer_jbd(bh))
 271                 return 1;
 272 
 273         /* Ok, locally the buffer is marked as up to date, now search
 274          * our cache to see if we can trust that. */
 275         return ocfs2_buffer_cached(ci, bh);
 276 }
 277 
 278 /*
 279  * Determine whether a buffer is currently out on a read-ahead request.
 280  * ci_io_sem should be held to serialize submitters with the logic here.
 281  */
 282 int ocfs2_buffer_read_ahead(struct ocfs2_caching_info *ci,
 283                             struct buffer_head *bh)
 284 {
 285         return buffer_locked(bh) && ocfs2_buffer_cached(ci, bh);
 286 }
 287 
 288 /* Requires ip_lock */
 289 static void ocfs2_append_cache_array(struct ocfs2_caching_info *ci,
 290                                      sector_t block)
 291 {
 292         BUG_ON(ci->ci_num_cached >= OCFS2_CACHE_INFO_MAX_ARRAY);
 293 
 294         trace_ocfs2_append_cache_array(
 295                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 296                 (unsigned long long)block, ci->ci_num_cached);
 297 
 298         ci->ci_cache.ci_array[ci->ci_num_cached] = block;
 299         ci->ci_num_cached++;
 300 }
 301 
 302 /* By now the caller should have checked that the item does *not*
 303  * exist in the tree.
 304  * Requires ip_lock. */
 305 static void __ocfs2_insert_cache_tree(struct ocfs2_caching_info *ci,
 306                                       struct ocfs2_meta_cache_item *new)
 307 {
 308         sector_t block = new->c_block;
 309         struct rb_node *parent = NULL;
 310         struct rb_node **p = &ci->ci_cache.ci_tree.rb_node;
 311         struct ocfs2_meta_cache_item *tmp;
 312 
 313         trace_ocfs2_insert_cache_tree(
 314                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 315                 (unsigned long long)block, ci->ci_num_cached);
 316 
 317         while(*p) {
 318                 parent = *p;
 319 
 320                 tmp = rb_entry(parent, struct ocfs2_meta_cache_item, c_node);
 321 
 322                 if (block < tmp->c_block)
 323                         p = &(*p)->rb_left;
 324                 else if (block > tmp->c_block)
 325                         p = &(*p)->rb_right;
 326                 else {
 327                         /* This should never happen! */
 328                         mlog(ML_ERROR, "Duplicate block %llu cached!\n",
 329                              (unsigned long long) block);
 330                         BUG();
 331                 }
 332         }
 333 
 334         rb_link_node(&new->c_node, parent, p);
 335         rb_insert_color(&new->c_node, &ci->ci_cache.ci_tree);
 336         ci->ci_num_cached++;
 337 }
 338 
 339 /* co_cache_lock() must be held */
 340 static inline int ocfs2_insert_can_use_array(struct ocfs2_caching_info *ci)
 341 {
 342         return (ci->ci_flags & OCFS2_CACHE_FL_INLINE) &&
 343                 (ci->ci_num_cached < OCFS2_CACHE_INFO_MAX_ARRAY);
 344 }
 345 
 346 /* tree should be exactly OCFS2_CACHE_INFO_MAX_ARRAY wide. NULL the
 347  * pointers in tree after we use them - this allows caller to detect
 348  * when to free in case of error.
 349  *
 350  * The co_cache_lock() must be held. */
 351 static void ocfs2_expand_cache(struct ocfs2_caching_info *ci,
 352                                struct ocfs2_meta_cache_item **tree)
 353 {
 354         int i;
 355 
 356         mlog_bug_on_msg(ci->ci_num_cached != OCFS2_CACHE_INFO_MAX_ARRAY,
 357                         "Owner %llu, num cached = %u, should be %u\n",
 358                         (unsigned long long)ocfs2_metadata_cache_owner(ci),
 359                         ci->ci_num_cached, OCFS2_CACHE_INFO_MAX_ARRAY);
 360         mlog_bug_on_msg(!(ci->ci_flags & OCFS2_CACHE_FL_INLINE),
 361                         "Owner %llu not marked as inline anymore!\n",
 362                         (unsigned long long)ocfs2_metadata_cache_owner(ci));
 363 
 364         /* Be careful to initialize the tree members *first* because
 365          * once the ci_tree is used, the array is junk... */
 366         for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++)
 367                 tree[i]->c_block = ci->ci_cache.ci_array[i];
 368 
 369         ci->ci_flags &= ~OCFS2_CACHE_FL_INLINE;
 370         ci->ci_cache.ci_tree = RB_ROOT;
 371         /* this will be set again by __ocfs2_insert_cache_tree */
 372         ci->ci_num_cached = 0;
 373 
 374         for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++) {
 375                 __ocfs2_insert_cache_tree(ci, tree[i]);
 376                 tree[i] = NULL;
 377         }
 378 
 379         trace_ocfs2_expand_cache(
 380                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 381                 ci->ci_flags, ci->ci_num_cached);
 382 }
 383 
 384 /* Slow path function - memory allocation is necessary. See the
 385  * comment above ocfs2_set_buffer_uptodate for more information. */
 386 static void __ocfs2_set_buffer_uptodate(struct ocfs2_caching_info *ci,
 387                                         sector_t block,
 388                                         int expand_tree)
 389 {
 390         int i;
 391         struct ocfs2_meta_cache_item *new = NULL;
 392         struct ocfs2_meta_cache_item *tree[OCFS2_CACHE_INFO_MAX_ARRAY] =
 393                 { NULL, };
 394 
 395         trace_ocfs2_set_buffer_uptodate(
 396                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 397                 (unsigned long long)block, expand_tree);
 398 
 399         new = kmem_cache_alloc(ocfs2_uptodate_cachep, GFP_NOFS);
 400         if (!new) {
 401                 mlog_errno(-ENOMEM);
 402                 return;
 403         }
 404         new->c_block = block;
 405 
 406         if (expand_tree) {
 407                 /* Do *not* allocate an array here - the removal code
 408                  * has no way of tracking that. */
 409                 for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++) {
 410                         tree[i] = kmem_cache_alloc(ocfs2_uptodate_cachep,
 411                                                    GFP_NOFS);
 412                         if (!tree[i]) {
 413                                 mlog_errno(-ENOMEM);
 414                                 goto out_free;
 415                         }
 416 
 417                         /* These are initialized in ocfs2_expand_cache! */
 418                 }
 419         }
 420 
 421         ocfs2_metadata_cache_lock(ci);
 422         if (ocfs2_insert_can_use_array(ci)) {
 423                 /* Ok, items were removed from the cache in between
 424                  * locks. Detect this and revert back to the fast path */
 425                 ocfs2_append_cache_array(ci, block);
 426                 ocfs2_metadata_cache_unlock(ci);
 427                 goto out_free;
 428         }
 429 
 430         if (expand_tree)
 431                 ocfs2_expand_cache(ci, tree);
 432 
 433         __ocfs2_insert_cache_tree(ci, new);
 434         ocfs2_metadata_cache_unlock(ci);
 435 
 436         new = NULL;
 437 out_free:
 438         if (new)
 439                 kmem_cache_free(ocfs2_uptodate_cachep, new);
 440 
 441         /* If these were used, then ocfs2_expand_cache re-set them to
 442          * NULL for us. */
 443         if (tree[0]) {
 444                 for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++)
 445                         if (tree[i])
 446                                 kmem_cache_free(ocfs2_uptodate_cachep,
 447                                                 tree[i]);
 448         }
 449 }
 450 
 451 /* Item insertion is guarded by co_io_lock(), so the insertion path takes
 452  * advantage of this by not rechecking for a duplicate insert during
 453  * the slow case. Additionally, if the cache needs to be bumped up to
 454  * a tree, the code will not recheck after acquiring the lock --
 455  * multiple paths cannot be expanding to a tree at the same time.
 456  *
 457  * The slow path takes into account that items can be removed
 458  * (including the whole tree wiped and reset) when this process it out
 459  * allocating memory. In those cases, it reverts back to the fast
 460  * path.
 461  *
 462  * Note that this function may actually fail to insert the block if
 463  * memory cannot be allocated. This is not fatal however (but may
 464  * result in a performance penalty)
 465  *
 466  * Readahead buffers can be passed in here before the I/O request is
 467  * completed.
 468  */
 469 void ocfs2_set_buffer_uptodate(struct ocfs2_caching_info *ci,
 470                                struct buffer_head *bh)
 471 {
 472         int expand;
 473 
 474         /* The block may very well exist in our cache already, so avoid
 475          * doing any more work in that case. */
 476         if (ocfs2_buffer_cached(ci, bh))
 477                 return;
 478 
 479         trace_ocfs2_set_buffer_uptodate_begin(
 480                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 481                 (unsigned long long)bh->b_blocknr);
 482 
 483         /* No need to recheck under spinlock - insertion is guarded by
 484          * co_io_lock() */
 485         ocfs2_metadata_cache_lock(ci);
 486         if (ocfs2_insert_can_use_array(ci)) {
 487                 /* Fast case - it's an array and there's a free
 488                  * spot. */
 489                 ocfs2_append_cache_array(ci, bh->b_blocknr);
 490                 ocfs2_metadata_cache_unlock(ci);
 491                 return;
 492         }
 493 
 494         expand = 0;
 495         if (ci->ci_flags & OCFS2_CACHE_FL_INLINE) {
 496                 /* We need to bump things up to a tree. */
 497                 expand = 1;
 498         }
 499         ocfs2_metadata_cache_unlock(ci);
 500 
 501         __ocfs2_set_buffer_uptodate(ci, bh->b_blocknr, expand);
 502 }
 503 
 504 /* Called against a newly allocated buffer. Most likely nobody should
 505  * be able to read this sort of metadata while it's still being
 506  * allocated, but this is careful to take co_io_lock() anyway. */
 507 void ocfs2_set_new_buffer_uptodate(struct ocfs2_caching_info *ci,
 508                                    struct buffer_head *bh)
 509 {
 510         /* This should definitely *not* exist in our cache */
 511         BUG_ON(ocfs2_buffer_cached(ci, bh));
 512 
 513         set_buffer_uptodate(bh);
 514 
 515         ocfs2_metadata_cache_io_lock(ci);
 516         ocfs2_set_buffer_uptodate(ci, bh);
 517         ocfs2_metadata_cache_io_unlock(ci);
 518 }
 519 
 520 /* Requires ip_lock. */
 521 static void ocfs2_remove_metadata_array(struct ocfs2_caching_info *ci,
 522                                         int index)
 523 {
 524         sector_t *array = ci->ci_cache.ci_array;
 525         int bytes;
 526 
 527         BUG_ON(index < 0 || index >= OCFS2_CACHE_INFO_MAX_ARRAY);
 528         BUG_ON(index >= ci->ci_num_cached);
 529         BUG_ON(!ci->ci_num_cached);
 530 
 531         trace_ocfs2_remove_metadata_array(
 532                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 533                 index, ci->ci_num_cached);
 534 
 535         ci->ci_num_cached--;
 536 
 537         /* don't need to copy if the array is now empty, or if we
 538          * removed at the tail */
 539         if (ci->ci_num_cached && index < ci->ci_num_cached) {
 540                 bytes = sizeof(sector_t) * (ci->ci_num_cached - index);
 541                 memmove(&array[index], &array[index + 1], bytes);
 542         }
 543 }
 544 
 545 /* Requires ip_lock. */
 546 static void ocfs2_remove_metadata_tree(struct ocfs2_caching_info *ci,
 547                                        struct ocfs2_meta_cache_item *item)
 548 {
 549         trace_ocfs2_remove_metadata_tree(
 550                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 551                 (unsigned long long)item->c_block);
 552 
 553         rb_erase(&item->c_node, &ci->ci_cache.ci_tree);
 554         ci->ci_num_cached--;
 555 }
 556 
 557 static void ocfs2_remove_block_from_cache(struct ocfs2_caching_info *ci,
 558                                           sector_t block)
 559 {
 560         int index;
 561         struct ocfs2_meta_cache_item *item = NULL;
 562 
 563         ocfs2_metadata_cache_lock(ci);
 564         trace_ocfs2_remove_block_from_cache(
 565                 (unsigned long long)ocfs2_metadata_cache_owner(ci),
 566                 (unsigned long long) block, ci->ci_num_cached,
 567                 ci->ci_flags);
 568 
 569         if (ci->ci_flags & OCFS2_CACHE_FL_INLINE) {
 570                 index = ocfs2_search_cache_array(ci, block);
 571                 if (index != -1)
 572                         ocfs2_remove_metadata_array(ci, index);
 573         } else {
 574                 item = ocfs2_search_cache_tree(ci, block);
 575                 if (item)
 576                         ocfs2_remove_metadata_tree(ci, item);
 577         }
 578         ocfs2_metadata_cache_unlock(ci);
 579 
 580         if (item)
 581                 kmem_cache_free(ocfs2_uptodate_cachep, item);
 582 }
 583 
 584 /*
 585  * Called when we remove a chunk of metadata from an inode. We don't
 586  * bother reverting things to an inlined array in the case of a remove
 587  * which moves us back under the limit.
 588  */
 589 void ocfs2_remove_from_cache(struct ocfs2_caching_info *ci,
 590                              struct buffer_head *bh)
 591 {
 592         sector_t block = bh->b_blocknr;
 593 
 594         ocfs2_remove_block_from_cache(ci, block);
 595 }
 596 
 597 /* Called when we remove xattr clusters from an inode. */
 598 void ocfs2_remove_xattr_clusters_from_cache(struct ocfs2_caching_info *ci,
 599                                             sector_t block,
 600                                             u32 c_len)
 601 {
 602         struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
 603         unsigned int i, b_len = ocfs2_clusters_to_blocks(sb, 1) * c_len;
 604 
 605         for (i = 0; i < b_len; i++, block++)
 606                 ocfs2_remove_block_from_cache(ci, block);
 607 }
 608 
 609 int __init init_ocfs2_uptodate_cache(void)
 610 {
 611         ocfs2_uptodate_cachep = kmem_cache_create("ocfs2_uptodate",
 612                                   sizeof(struct ocfs2_meta_cache_item),
 613                                   0, SLAB_HWCACHE_ALIGN, NULL);
 614         if (!ocfs2_uptodate_cachep)
 615                 return -ENOMEM;
 616 
 617         return 0;
 618 }
 619 
 620 void exit_ocfs2_uptodate_cache(void)
 621 {
 622         kmem_cache_destroy(ocfs2_uptodate_cachep);
 623 }