Pileus Git - ~andy/linux/blob - fs/hfsplus/bnode.c

   1 /*
   2  *  linux/fs/hfsplus/bnode.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer (flar@allandria.com)
   6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   7  *
   8  * Handle basic btree node operations
   9  */
  10
  11 #include <linux/string.h>
  12 #include <linux/slab.h>
  13 #include <linux/pagemap.h>
  14 #include <linux/fs.h>
  15 #include <linux/swap.h>
  16
  17 #include "hfsplus_fs.h"
  18 #include "hfsplus_raw.h"
  19
  20 /* Copy a specified range of bytes from the raw data of a node */
  21 void hfs_bnode_read(struct hfs_bnode *node, void *buf, int off, int len)
  22 {
  23         struct page **pagep;
  24         int l;
  25
  26         off += node->page_offset;
  27         pagep = node->page + (off >> PAGE_CACHE_SHIFT);
  28         off &= ~PAGE_CACHE_MASK;
  29
  30         l = min(len, (int)PAGE_CACHE_SIZE - off);
  31         memcpy(buf, kmap(*pagep) + off, l);
  32         kunmap(*pagep);
  33
  34         while ((len -= l) != 0) {
  35                 buf += l;
  36                 l = min(len, (int)PAGE_CACHE_SIZE);
  37                 memcpy(buf, kmap(*++pagep), l);
  38                 kunmap(*pagep);
  39         }
  40 }
  41
  42 u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off)
  43 {
  44         __be16 data;
  45         /* TODO: optimize later... */
  46         hfs_bnode_read(node, &data, off, 2);
  47         return be16_to_cpu(data);
  48 }
  49
  50 u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off)
  51 {
  52         u8 data;
  53         /* TODO: optimize later... */
  54         hfs_bnode_read(node, &data, off, 1);
  55         return data;
  56 }
  57
  58 void hfs_bnode_read_key(struct hfs_bnode *node, void *key, int off)
  59 {
  60         struct hfs_btree *tree;
  61         int key_len;
  62
  63         tree = node->tree;
  64         if (node->type == HFS_NODE_LEAF ||
  65             tree->attributes & HFS_TREE_VARIDXKEYS ||
  66             node->tree->cnid == HFSPLUS_ATTR_CNID)
  67                 key_len = hfs_bnode_read_u16(node, off) + 2;
  68         else
  69                 key_len = tree->max_key_len + 2;
  70
  71         hfs_bnode_read(node, key, off, key_len);
  72 }
  73
  74 void hfs_bnode_write(struct hfs_bnode *node, void *buf, int off, int len)
  75 {
  76         struct page **pagep;
  77         int l;
  78
  79         off += node->page_offset;
  80         pagep = node->page + (off >> PAGE_CACHE_SHIFT);
  81         off &= ~PAGE_CACHE_MASK;
  82
  83         l = min(len, (int)PAGE_CACHE_SIZE - off);
  84         memcpy(kmap(*pagep) + off, buf, l);
  85         set_page_dirty(*pagep);
  86         kunmap(*pagep);
  87
  88         while ((len -= l) != 0) {
  89                 buf += l;
  90                 l = min(len, (int)PAGE_CACHE_SIZE);
  91                 memcpy(kmap(*++pagep), buf, l);
  92                 set_page_dirty(*pagep);
  93                 kunmap(*pagep);
  94         }
  95 }
  96
  97 void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data)
  98 {
  99         __be16 v = cpu_to_be16(data);
 100         /* TODO: optimize later... */
 101         hfs_bnode_write(node, &v, off, 2);
 102 }
 103
 104 void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
 105 {
 106         struct page **pagep;
 107         int l;
 108
 109         off += node->page_offset;
 110         pagep = node->page + (off >> PAGE_CACHE_SHIFT);
 111         off &= ~PAGE_CACHE_MASK;
 112
 113         l = min(len, (int)PAGE_CACHE_SIZE - off);
 114         memset(kmap(*pagep) + off, 0, l);
 115         set_page_dirty(*pagep);
 116         kunmap(*pagep);
 117
 118         while ((len -= l) != 0) {
 119                 l = min(len, (int)PAGE_CACHE_SIZE);
 120                 memset(kmap(*++pagep), 0, l);
 121                 set_page_dirty(*pagep);
 122                 kunmap(*pagep);
 123         }
 124 }
 125
 126 void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
 127                     struct hfs_bnode *src_node, int src, int len)
 128 {
 129         struct hfs_btree *tree;
 130         struct page **src_page, **dst_page;
 131         int l;
 132
 133         hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
 134         if (!len)
 135                 return;
 136         tree = src_node->tree;
 137         src += src_node->page_offset;
 138         dst += dst_node->page_offset;
 139         src_page = src_node->page + (src >> PAGE_CACHE_SHIFT);
 140         src &= ~PAGE_CACHE_MASK;
 141         dst_page = dst_node->page + (dst >> PAGE_CACHE_SHIFT);
 142         dst &= ~PAGE_CACHE_MASK;
 143
 144         if (src == dst) {
 145                 l = min(len, (int)PAGE_CACHE_SIZE - src);
 146                 memcpy(kmap(*dst_page) + src, kmap(*src_page) + src, l);
 147                 kunmap(*src_page);
 148                 set_page_dirty(*dst_page);
 149                 kunmap(*dst_page);
 150
 151                 while ((len -= l) != 0) {
 152                         l = min(len, (int)PAGE_CACHE_SIZE);
 153                         memcpy(kmap(*++dst_page), kmap(*++src_page), l);
 154                         kunmap(*src_page);
 155                         set_page_dirty(*dst_page);
 156                         kunmap(*dst_page);
 157                 }
 158         } else {
 159                 void *src_ptr, *dst_ptr;
 160
 161                 do {
 162                         src_ptr = kmap(*src_page) + src;
 163                         dst_ptr = kmap(*dst_page) + dst;
 164                         if (PAGE_CACHE_SIZE - src < PAGE_CACHE_SIZE - dst) {
 165                                 l = PAGE_CACHE_SIZE - src;
 166                                 src = 0;
 167                                 dst += l;
 168                         } else {
 169                                 l = PAGE_CACHE_SIZE - dst;
 170                                 src += l;
 171                                 dst = 0;
 172                         }
 173                         l = min(len, l);
 174                         memcpy(dst_ptr, src_ptr, l);
 175                         kunmap(*src_page);
 176                         set_page_dirty(*dst_page);
 177                         kunmap(*dst_page);
 178                         if (!dst)
 179                                 dst_page++;
 180                         else
 181                                 src_page++;
 182                 } while ((len -= l));
 183         }
 184 }
 185
 186 void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len)
 187 {
 188         struct page **src_page, **dst_page;
 189         int l;
 190
 191         hfs_dbg(BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len);
 192         if (!len)
 193                 return;
 194         src += node->page_offset;
 195         dst += node->page_offset;
 196         if (dst > src) {
 197                 src += len - 1;
 198                 src_page = node->page + (src >> PAGE_CACHE_SHIFT);
 199                 src = (src & ~PAGE_CACHE_MASK) + 1;
 200                 dst += len - 1;
 201                 dst_page = node->page + (dst >> PAGE_CACHE_SHIFT);
 202                 dst = (dst & ~PAGE_CACHE_MASK) + 1;
 203
 204                 if (src == dst) {
 205                         while (src < len) {
 206                                 memmove(kmap(*dst_page), kmap(*src_page), src);
 207                                 kunmap(*src_page);
 208                                 set_page_dirty(*dst_page);
 209                                 kunmap(*dst_page);
 210                                 len -= src;
 211                                 src = PAGE_CACHE_SIZE;
 212                                 src_page--;
 213                                 dst_page--;
 214                         }
 215                         src -= len;
 216                         memmove(kmap(*dst_page) + src,
 217                                 kmap(*src_page) + src, len);
 218                         kunmap(*src_page);
 219                         set_page_dirty(*dst_page);
 220                         kunmap(*dst_page);
 221                 } else {
 222                         void *src_ptr, *dst_ptr;
 223
 224                         do {
 225                                 src_ptr = kmap(*src_page) + src;
 226                                 dst_ptr = kmap(*dst_page) + dst;
 227                                 if (src < dst) {
 228                                         l = src;
 229                                         src = PAGE_CACHE_SIZE;
 230                                         dst -= l;
 231                                 } else {
 232                                         l = dst;
 233                                         src -= l;
 234                                         dst = PAGE_CACHE_SIZE;
 235                                 }
 236                                 l = min(len, l);
 237                                 memmove(dst_ptr - l, src_ptr - l, l);
 238                                 kunmap(*src_page);
 239                                 set_page_dirty(*dst_page);
 240                                 kunmap(*dst_page);
 241                                 if (dst == PAGE_CACHE_SIZE)
 242                                         dst_page--;
 243                                 else
 244                                         src_page--;
 245                         } while ((len -= l));
 246                 }
 247         } else {
 248                 src_page = node->page + (src >> PAGE_CACHE_SHIFT);
 249                 src &= ~PAGE_CACHE_MASK;
 250                 dst_page = node->page + (dst >> PAGE_CACHE_SHIFT);
 251                 dst &= ~PAGE_CACHE_MASK;
 252
 253                 if (src == dst) {
 254                         l = min(len, (int)PAGE_CACHE_SIZE - src);
 255                         memmove(kmap(*dst_page) + src,
 256                                 kmap(*src_page) + src, l);
 257                         kunmap(*src_page);
 258                         set_page_dirty(*dst_page);
 259                         kunmap(*dst_page);
 260
 261                         while ((len -= l) != 0) {
 262                                 l = min(len, (int)PAGE_CACHE_SIZE);
 263                                 memmove(kmap(*++dst_page),
 264                                         kmap(*++src_page), l);
 265                                 kunmap(*src_page);
 266                                 set_page_dirty(*dst_page);
 267                                 kunmap(*dst_page);
 268                         }
 269                 } else {
 270                         void *src_ptr, *dst_ptr;
 271
 272                         do {
 273                                 src_ptr = kmap(*src_page) + src;
 274                                 dst_ptr = kmap(*dst_page) + dst;
 275                                 if (PAGE_CACHE_SIZE - src <
 276                                                 PAGE_CACHE_SIZE - dst) {
 277                                         l = PAGE_CACHE_SIZE - src;
 278                                         src = 0;
 279                                         dst += l;
 280                                 } else {
 281                                         l = PAGE_CACHE_SIZE - dst;
 282                                         src += l;
 283                                         dst = 0;
 284                                 }
 285                                 l = min(len, l);
 286                                 memmove(dst_ptr, src_ptr, l);
 287                                 kunmap(*src_page);
 288                                 set_page_dirty(*dst_page);
 289                                 kunmap(*dst_page);
 290                                 if (!dst)
 291                                         dst_page++;
 292                                 else
 293                                         src_page++;
 294                         } while ((len -= l));
 295                 }
 296         }
 297 }
 298
 299 void hfs_bnode_dump(struct hfs_bnode *node)
 300 {
 301         struct hfs_bnode_desc desc;
 302         __be32 cnid;
 303         int i, off, key_off;
 304
 305         hfs_dbg(BNODE_MOD, "bnode: %d\n", node->this);
 306         hfs_bnode_read(node, &desc, 0, sizeof(desc));
 307         hfs_dbg(BNODE_MOD, "%d, %d, %d, %d, %d\n",
 308                 be32_to_cpu(desc.next), be32_to_cpu(desc.prev),
 309                 desc.type, desc.height, be16_to_cpu(desc.num_recs));
 310
 311         off = node->tree->node_size - 2;
 312         for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) {
 313                 key_off = hfs_bnode_read_u16(node, off);
 314                 hfs_dbg(BNODE_MOD, " %d", key_off);
 315                 if (i && node->type == HFS_NODE_INDEX) {
 316                         int tmp;
 317
 318                         if (node->tree->attributes & HFS_TREE_VARIDXKEYS ||
 319                                         node->tree->cnid == HFSPLUS_ATTR_CNID)
 320                                 tmp = hfs_bnode_read_u16(node, key_off) + 2;
 321                         else
 322                                 tmp = node->tree->max_key_len + 2;
 323                         hfs_dbg_cont(BNODE_MOD, " (%d", tmp);
 324                         hfs_bnode_read(node, &cnid, key_off + tmp, 4);
 325                         hfs_dbg_cont(BNODE_MOD, ",%d)", be32_to_cpu(cnid));
 326                 } else if (i && node->type == HFS_NODE_LEAF) {
 327                         int tmp;
 328
 329                         tmp = hfs_bnode_read_u16(node, key_off);
 330                         hfs_dbg_cont(BNODE_MOD, " (%d)", tmp);
 331                 }
 332         }
 333         hfs_dbg_cont(BNODE_MOD, "\n");
 334 }
 335
 336 void hfs_bnode_unlink(struct hfs_bnode *node)
 337 {
 338         struct hfs_btree *tree;
 339         struct hfs_bnode *tmp;
 340         __be32 cnid;
 341
 342         tree = node->tree;
 343         if (node->prev) {
 344                 tmp = hfs_bnode_find(tree, node->prev);
 345                 if (IS_ERR(tmp))
 346                         return;
 347                 tmp->next = node->next;
 348                 cnid = cpu_to_be32(tmp->next);
 349                 hfs_bnode_write(tmp, &cnid,
 350                         offsetof(struct hfs_bnode_desc, next), 4);
 351                 hfs_bnode_put(tmp);
 352         } else if (node->type == HFS_NODE_LEAF)
 353                 tree->leaf_head = node->next;
 354
 355         if (node->next) {
 356                 tmp = hfs_bnode_find(tree, node->next);
 357                 if (IS_ERR(tmp))
 358                         return;
 359                 tmp->prev = node->prev;
 360                 cnid = cpu_to_be32(tmp->prev);
 361                 hfs_bnode_write(tmp, &cnid,
 362                         offsetof(struct hfs_bnode_desc, prev), 4);
 363                 hfs_bnode_put(tmp);
 364         } else if (node->type == HFS_NODE_LEAF)
 365                 tree->leaf_tail = node->prev;
 366
 367         /* move down? */
 368         if (!node->prev && !node->next)
 369                 hfs_dbg(BNODE_MOD, "hfs_btree_del_level\n");
 370         if (!node->parent) {
 371                 tree->root = 0;
 372                 tree->depth = 0;
 373         }
 374         set_bit(HFS_BNODE_DELETED, &node->flags);
 375 }
 376
 377 static inline int hfs_bnode_hash(u32 num)
 378 {
 379         num = (num >> 16) + num;
 380         num += num >> 8;
 381         return num & (NODE_HASH_SIZE - 1);
 382 }
 383
 384 struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
 385 {
 386         struct hfs_bnode *node;
 387
 388         if (cnid >= tree->node_count) {
 389                 pr_err("request for non-existent node "
 390                                 "%d in B*Tree\n",
 391                         cnid);
 392                 return NULL;
 393         }
 394
 395         for (node = tree->node_hash[hfs_bnode_hash(cnid)];
 396                         node; node = node->next_hash)
 397                 if (node->this == cnid)
 398                         return node;
 399         return NULL;
 400 }
 401
 402 static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 403 {
 404         struct super_block *sb;
 405         struct hfs_bnode *node, *node2;
 406         struct address_space *mapping;
 407         struct page *page;
 408         int size, block, i, hash;
 409         loff_t off;
 410
 411         if (cnid >= tree->node_count) {
 412                 pr_err("request for non-existent node "
 413                                 "%d in B*Tree\n",
 414                         cnid);
 415                 return NULL;
 416         }
 417
 418         sb = tree->inode->i_sb;
 419         size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
 420                 sizeof(struct page *);
 421         node = kzalloc(size, GFP_KERNEL);
 422         if (!node)
 423                 return NULL;
 424         node->tree = tree;
 425         node->this = cnid;
 426         set_bit(HFS_BNODE_NEW, &node->flags);
 427         atomic_set(&node->refcnt, 1);
 428         hfs_dbg(BNODE_REFS, "new_node(%d:%d): 1\n",
 429                 node->tree->cnid, node->this);
 430         init_waitqueue_head(&node->lock_wq);
 431         spin_lock(&tree->hash_lock);
 432         node2 = hfs_bnode_findhash(tree, cnid);
 433         if (!node2) {
 434                 hash = hfs_bnode_hash(cnid);
 435                 node->next_hash = tree->node_hash[hash];
 436                 tree->node_hash[hash] = node;
 437                 tree->node_hash_cnt++;
 438         } else {
 439                 spin_unlock(&tree->hash_lock);
 440                 kfree(node);
 441                 wait_event(node2->lock_wq,
 442                         !test_bit(HFS_BNODE_NEW, &node2->flags));
 443                 return node2;
 444         }
 445         spin_unlock(&tree->hash_lock);
 446
 447         mapping = tree->inode->i_mapping;
 448         off = (loff_t)cnid << tree->node_size_shift;
 449         block = off >> PAGE_CACHE_SHIFT;
 450         node->page_offset = off & ~PAGE_CACHE_MASK;
 451         for (i = 0; i < tree->pages_per_bnode; block++, i++) {
 452                 page = read_mapping_page(mapping, block, NULL);
 453                 if (IS_ERR(page))
 454                         goto fail;
 455                 if (PageError(page)) {
 456                         page_cache_release(page);
 457                         goto fail;
 458                 }
 459                 page_cache_release(page);
 460                 node->page[i] = page;
 461         }
 462
 463         return node;
 464 fail:
 465         set_bit(HFS_BNODE_ERROR, &node->flags);
 466         return node;
 467 }
 468
 469 void hfs_bnode_unhash(struct hfs_bnode *node)
 470 {
 471         struct hfs_bnode **p;
 472
 473         hfs_dbg(BNODE_REFS, "remove_node(%d:%d): %d\n",
 474                 node->tree->cnid, node->this, atomic_read(&node->refcnt));
 475         for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)];
 476              *p && *p != node; p = &(*p)->next_hash)
 477                 ;
 478         BUG_ON(!*p);
 479         *p = node->next_hash;
 480         node->tree->node_hash_cnt--;
 481 }
 482
 483 /* Load a particular node out of a tree */
 484 struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
 485 {
 486         struct hfs_bnode *node;
 487         struct hfs_bnode_desc *desc;
 488         int i, rec_off, off, next_off;
 489         int entry_size, key_size;
 490
 491         spin_lock(&tree->hash_lock);
 492         node = hfs_bnode_findhash(tree, num);
 493         if (node) {
 494                 hfs_bnode_get(node);
 495                 spin_unlock(&tree->hash_lock);
 496                 wait_event(node->lock_wq,
 497                         !test_bit(HFS_BNODE_NEW, &node->flags));
 498                 if (test_bit(HFS_BNODE_ERROR, &node->flags))
 499                         goto node_error;
 500                 return node;
 501         }
 502         spin_unlock(&tree->hash_lock);
 503         node = __hfs_bnode_create(tree, num);
 504         if (!node)
 505                 return ERR_PTR(-ENOMEM);
 506         if (test_bit(HFS_BNODE_ERROR, &node->flags))
 507                 goto node_error;
 508         if (!test_bit(HFS_BNODE_NEW, &node->flags))
 509                 return node;
 510
 511         desc = (struct hfs_bnode_desc *)(kmap(node->page[0]) +
 512                         node->page_offset);
 513         node->prev = be32_to_cpu(desc->prev);
 514         node->next = be32_to_cpu(desc->next);
 515         node->num_recs = be16_to_cpu(desc->num_recs);
 516         node->type = desc->type;
 517         node->height = desc->height;
 518         kunmap(node->page[0]);
 519
 520         switch (node->type) {
 521         case HFS_NODE_HEADER:
 522         case HFS_NODE_MAP:
 523                 if (node->height != 0)
 524                         goto node_error;
 525                 break;
 526         case HFS_NODE_LEAF:
 527                 if (node->height != 1)
 528                         goto node_error;
 529                 break;
 530         case HFS_NODE_INDEX:
 531                 if (node->height <= 1 || node->height > tree->depth)
 532                         goto node_error;
 533                 break;
 534         default:
 535                 goto node_error;
 536         }
 537
 538         rec_off = tree->node_size - 2;
 539         off = hfs_bnode_read_u16(node, rec_off);
 540         if (off != sizeof(struct hfs_bnode_desc))
 541                 goto node_error;
 542         for (i = 1; i <= node->num_recs; off = next_off, i++) {
 543                 rec_off -= 2;
 544                 next_off = hfs_bnode_read_u16(node, rec_off);
 545                 if (next_off <= off ||
 546                     next_off > tree->node_size ||
 547                     next_off & 1)
 548                         goto node_error;
 549                 entry_size = next_off - off;
 550                 if (node->type != HFS_NODE_INDEX &&
 551                     node->type != HFS_NODE_LEAF)
 552                         continue;
 553                 key_size = hfs_bnode_read_u16(node, off) + 2;
 554                 if (key_size >= entry_size || key_size & 1)
 555                         goto node_error;
 556         }
 557         clear_bit(HFS_BNODE_NEW, &node->flags);
 558         wake_up(&node->lock_wq);
 559         return node;
 560
 561 node_error:
 562         set_bit(HFS_BNODE_ERROR, &node->flags);
 563         clear_bit(HFS_BNODE_NEW, &node->flags);
 564         wake_up(&node->lock_wq);
 565         hfs_bnode_put(node);
 566         return ERR_PTR(-EIO);
 567 }
 568
 569 void hfs_bnode_free(struct hfs_bnode *node)
 570 {
 571 #if 0
 572         int i;
 573
 574         for (i = 0; i < node->tree->pages_per_bnode; i++)
 575                 if (node->page[i])
 576                         page_cache_release(node->page[i]);
 577 #endif
 578         kfree(node);
 579 }
 580
 581 struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num)
 582 {
 583         struct hfs_bnode *node;
 584         struct page **pagep;
 585         int i;
 586
 587         spin_lock(&tree->hash_lock);
 588         node = hfs_bnode_findhash(tree, num);
 589         spin_unlock(&tree->hash_lock);
 590         if (node) {
 591                 pr_crit("new node %u already hashed?\n", num);
 592                 WARN_ON(1);
 593                 return node;
 594         }
 595         node = __hfs_bnode_create(tree, num);
 596         if (!node)
 597                 return ERR_PTR(-ENOMEM);
 598         if (test_bit(HFS_BNODE_ERROR, &node->flags)) {
 599                 hfs_bnode_put(node);
 600                 return ERR_PTR(-EIO);
 601         }
 602
 603         pagep = node->page;
 604         memset(kmap(*pagep) + node->page_offset, 0,
 605                min((int)PAGE_CACHE_SIZE, (int)tree->node_size));
 606         set_page_dirty(*pagep);
 607         kunmap(*pagep);
 608         for (i = 1; i < tree->pages_per_bnode; i++) {
 609                 memset(kmap(*++pagep), 0, PAGE_CACHE_SIZE);
 610                 set_page_dirty(*pagep);
 611                 kunmap(*pagep);
 612         }
 613         clear_bit(HFS_BNODE_NEW, &node->flags);
 614         wake_up(&node->lock_wq);
 615
 616         return node;
 617 }
 618
 619 void hfs_bnode_get(struct hfs_bnode *node)
 620 {
 621         if (node) {
 622                 atomic_inc(&node->refcnt);
 623                 hfs_dbg(BNODE_REFS, "get_node(%d:%d): %d\n",
 624                         node->tree->cnid, node->this,
 625                         atomic_read(&node->refcnt));
 626         }
 627 }
 628
 629 /* Dispose of resources used by a node */
 630 void hfs_bnode_put(struct hfs_bnode *node)
 631 {
 632         if (node) {
 633                 struct hfs_btree *tree = node->tree;
 634                 int i;
 635
 636                 hfs_dbg(BNODE_REFS, "put_node(%d:%d): %d\n",
 637                         node->tree->cnid, node->this,
 638                         atomic_read(&node->refcnt));
 639                 BUG_ON(!atomic_read(&node->refcnt));
 640                 if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock))
 641                         return;
 642                 for (i = 0; i < tree->pages_per_bnode; i++) {
 643                         if (!node->page[i])
 644                                 continue;
 645                         mark_page_accessed(node->page[i]);
 646                 }
 647
 648                 if (test_bit(HFS_BNODE_DELETED, &node->flags)) {
 649                         hfs_bnode_unhash(node);
 650                         spin_unlock(&tree->hash_lock);
 651                         hfs_bnode_clear(node, 0,
 652                                 PAGE_CACHE_SIZE * tree->pages_per_bnode);
 653                         hfs_bmap_free(node);
 654                         hfs_bnode_free(node);
 655                         return;
 656                 }
 657                 spin_unlock(&tree->hash_lock);
 658         }
 659 }
 660