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   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 #include <linux/version.h>
  17
  18 #include "hfsplus_fs.h"
  19 #include "hfsplus_raw.h"
  20
  21 #define REF_PAGES       0
  22
  23 /* Copy a specified range of bytes from the raw data of a node */
  24 void hfs_bnode_read(struct hfs_bnode *node, void *buf, int off, int len)
  25 {
  26         struct page **pagep;
  27         int l;
  28
  29         off += node->page_offset;
  30         pagep = node->page + (off >> PAGE_CACHE_SHIFT);
  31         off &= ~PAGE_CACHE_MASK;
  32
  33         l = min(len, (int)PAGE_CACHE_SIZE - off);
  34         memcpy(buf, kmap(*pagep) + off, l);
  35         kunmap(*pagep);
  36
  37         while ((len -= l) != 0) {
  38                 buf += l;
  39                 l = min(len, (int)PAGE_CACHE_SIZE);
  40                 memcpy(buf, kmap(*++pagep), l);
  41                 kunmap(*pagep);
  42         }
  43 }
  44
  45 u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off)
  46 {
  47         __be16 data;
  48         // optimize later...
  49         hfs_bnode_read(node, &data, off, 2);
  50         return be16_to_cpu(data);
  51 }
  52
  53 u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off)
  54 {
  55         u8 data;
  56         // optimize later...
  57         hfs_bnode_read(node, &data, off, 1);
  58         return data;
  59 }
  60
  61 void hfs_bnode_read_key(struct hfs_bnode *node, void *key, int off)
  62 {
  63         struct hfs_btree *tree;
  64         int key_len;
  65
  66         tree = node->tree;
  67         if (node->type == HFS_NODE_LEAF ||
  68             tree->attributes & HFS_TREE_VARIDXKEYS)
  69                 key_len = hfs_bnode_read_u16(node, off) + 2;
  70         else
  71                 key_len = tree->max_key_len + 2;
  72
  73         hfs_bnode_read(node, key, off, key_len);
  74 }
  75
  76 void hfs_bnode_write(struct hfs_bnode *node, void *buf, int off, int len)
  77 {
  78         struct page **pagep;
  79         int l;
  80
  81         off += node->page_offset;
  82         pagep = node->page + (off >> PAGE_CACHE_SHIFT);
  83         off &= ~PAGE_CACHE_MASK;
  84
  85         l = min(len, (int)PAGE_CACHE_SIZE - off);
  86         memcpy(kmap(*pagep) + off, buf, l);
  87         set_page_dirty(*pagep);
  88         kunmap(*pagep);
  89
  90         while ((len -= l) != 0) {
  91                 buf += l;
  92                 l = min(len, (int)PAGE_CACHE_SIZE);
  93                 memcpy(kmap(*++pagep), buf, l);
  94                 set_page_dirty(*pagep);
  95                 kunmap(*pagep);
  96         }
  97 }
  98
  99 void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data)
 100 {
 101         __be16 v = cpu_to_be16(data);
 102         // optimize later...
 103         hfs_bnode_write(node, &v, off, 2);
 104 }
 105
 106 void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
 107 {
 108         struct page **pagep;
 109         int l;
 110
 111         off += node->page_offset;
 112         pagep = node->page + (off >> PAGE_CACHE_SHIFT);
 113         off &= ~PAGE_CACHE_MASK;
 114
 115         l = min(len, (int)PAGE_CACHE_SIZE - off);
 116         memset(kmap(*pagep) + off, 0, l);
 117         set_page_dirty(*pagep);
 118         kunmap(*pagep);
 119
 120         while ((len -= l) != 0) {
 121                 l = min(len, (int)PAGE_CACHE_SIZE);
 122                 memset(kmap(*++pagep), 0, l);
 123                 set_page_dirty(*pagep);
 124                 kunmap(*pagep);
 125         }
 126 }
 127
 128 void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
 129                     struct hfs_bnode *src_node, int src, int len)
 130 {
 131         struct hfs_btree *tree;
 132         struct page **src_page, **dst_page;
 133         int l;
 134
 135         dprint(DBG_BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
 136         if (!len)
 137                 return;
 138         tree = src_node->tree;
 139         src += src_node->page_offset;
 140         dst += dst_node->page_offset;
 141         src_page = src_node->page + (src >> PAGE_CACHE_SHIFT);
 142         src &= ~PAGE_CACHE_MASK;
 143         dst_page = dst_node->page + (dst >> PAGE_CACHE_SHIFT);
 144         dst &= ~PAGE_CACHE_MASK;
 145
 146         if (src == dst) {
 147                 l = min(len, (int)PAGE_CACHE_SIZE - src);
 148                 memcpy(kmap(*dst_page) + src, kmap(*src_page) + src, l);
 149                 kunmap(*src_page);
 150                 set_page_dirty(*dst_page);
 151                 kunmap(*dst_page);
 152
 153                 while ((len -= l) != 0) {
 154                         l = min(len, (int)PAGE_CACHE_SIZE);
 155                         memcpy(kmap(*++dst_page), kmap(*++src_page), l);
 156                         kunmap(*src_page);
 157                         set_page_dirty(*dst_page);
 158                         kunmap(*dst_page);
 159                 }
 160         } else {
 161                 void *src_ptr, *dst_ptr;
 162
 163                 do {
 164                         src_ptr = kmap(*src_page) + src;
 165                         dst_ptr = kmap(*dst_page) + dst;
 166                         if (PAGE_CACHE_SIZE - src < PAGE_CACHE_SIZE - dst) {
 167                                 l = PAGE_CACHE_SIZE - src;
 168                                 src = 0;
 169                                 dst += l;
 170                         } else {
 171                                 l = PAGE_CACHE_SIZE - dst;
 172                                 src += l;
 173                                 dst = 0;
 174                         }
 175                         l = min(len, l);
 176                         memcpy(dst_ptr, src_ptr, l);
 177                         kunmap(*src_page);
 178                         set_page_dirty(*dst_page);
 179                         kunmap(*dst_page);
 180                         if (!dst)
 181                                 dst_page++;
 182                         else
 183                                 src_page++;
 184                 } while ((len -= l));
 185         }
 186 }
 187
 188 void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len)
 189 {
 190         struct page **src_page, **dst_page;
 191         int l;
 192
 193         dprint(DBG_BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len);
 194         if (!len)
 195                 return;
 196         src += node->page_offset;
 197         dst += node->page_offset;
 198         if (dst > src) {
 199                 src += len - 1;
 200                 src_page = node->page + (src >> PAGE_CACHE_SHIFT);
 201                 src = (src & ~PAGE_CACHE_MASK) + 1;
 202                 dst += len - 1;
 203                 dst_page = node->page + (dst >> PAGE_CACHE_SHIFT);
 204                 dst = (dst & ~PAGE_CACHE_MASK) + 1;
 205
 206                 if (src == dst) {
 207                         while (src < len) {
 208                                 memmove(kmap(*dst_page), kmap(*src_page), src);
 209                                 kunmap(*src_page);
 210                                 set_page_dirty(*dst_page);
 211                                 kunmap(*dst_page);
 212                                 len -= src;
 213                                 src = PAGE_CACHE_SIZE;
 214                                 src_page--;
 215                                 dst_page--;
 216                         }
 217                         src -= len;
 218                         memmove(kmap(*dst_page) + src, kmap(*src_page) + src, len);
 219                         kunmap(*src_page);
 220                         set_page_dirty(*dst_page);
 221                         kunmap(*dst_page);
 222                 } else {
 223                         void *src_ptr, *dst_ptr;
 224
 225                         do {
 226                                 src_ptr = kmap(*src_page) + src;
 227                                 dst_ptr = kmap(*dst_page) + dst;
 228                                 if (src < dst) {
 229                                         l = src;
 230                                         src = PAGE_CACHE_SIZE;
 231                                         dst -= l;
 232                                 } else {
 233                                         l = dst;
 234                                         src -= l;
 235                                         dst = PAGE_CACHE_SIZE;
 236                                 }
 237                                 l = min(len, l);
 238                                 memmove(dst_ptr - l, src_ptr - l, l);
 239                                 kunmap(*src_page);
 240                                 set_page_dirty(*dst_page);
 241                                 kunmap(*dst_page);
 242                                 if (dst == PAGE_CACHE_SIZE)
 243                                         dst_page--;
 244                                 else
 245                                         src_page--;
 246                         } while ((len -= l));
 247                 }
 248         } else {
 249                 src_page = node->page + (src >> PAGE_CACHE_SHIFT);
 250                 src &= ~PAGE_CACHE_MASK;
 251                 dst_page = node->page + (dst >> PAGE_CACHE_SHIFT);
 252                 dst &= ~PAGE_CACHE_MASK;
 253
 254                 if (src == dst) {
 255                         l = min(len, (int)PAGE_CACHE_SIZE - src);
 256                         memmove(kmap(*dst_page) + src, 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), kmap(*++src_page), l);
 264                                 kunmap(*src_page);
 265                                 set_page_dirty(*dst_page);
 266                                 kunmap(*dst_page);
 267                         }
 268                 } else {
 269                         void *src_ptr, *dst_ptr;
 270
 271                         do {
 272                                 src_ptr = kmap(*src_page) + src;
 273                                 dst_ptr = kmap(*dst_page) + dst;
 274                                 if (PAGE_CACHE_SIZE - src < PAGE_CACHE_SIZE - dst) {
 275                                         l = PAGE_CACHE_SIZE - src;
 276                                         src = 0;
 277                                         dst += l;
 278                                 } else {
 279                                         l = PAGE_CACHE_SIZE - dst;
 280                                         src += l;
 281                                         dst = 0;
 282                                 }
 283                                 l = min(len, l);
 284                                 memmove(dst_ptr, src_ptr, l);
 285                                 kunmap(*src_page);
 286                                 set_page_dirty(*dst_page);
 287                                 kunmap(*dst_page);
 288                                 if (!dst)
 289                                         dst_page++;
 290                                 else
 291                                         src_page++;
 292                         } while ((len -= l));
 293                 }
 294         }
 295 }
 296
 297 void hfs_bnode_dump(struct hfs_bnode *node)
 298 {
 299         struct hfs_bnode_desc desc;
 300         __be32 cnid;
 301         int i, off, key_off;
 302
 303         dprint(DBG_BNODE_MOD, "bnode: %d\n", node->this);
 304         hfs_bnode_read(node, &desc, 0, sizeof(desc));
 305         dprint(DBG_BNODE_MOD, "%d, %d, %d, %d, %d\n",
 306                 be32_to_cpu(desc.next), be32_to_cpu(desc.prev),
 307                 desc.type, desc.height, be16_to_cpu(desc.num_recs));
 308
 309         off = node->tree->node_size - 2;
 310         for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) {
 311                 key_off = hfs_bnode_read_u16(node, off);
 312                 dprint(DBG_BNODE_MOD, " %d", key_off);
 313                 if (i && node->type == HFS_NODE_INDEX) {
 314                         int tmp;
 315
 316                         if (node->tree->attributes & HFS_TREE_VARIDXKEYS)
 317                                 tmp = hfs_bnode_read_u16(node, key_off) + 2;
 318                         else
 319                                 tmp = node->tree->max_key_len + 2;
 320                         dprint(DBG_BNODE_MOD, " (%d", tmp);
 321                         hfs_bnode_read(node, &cnid, key_off + tmp, 4);
 322                         dprint(DBG_BNODE_MOD, ",%d)", be32_to_cpu(cnid));
 323                 } else if (i && node->type == HFS_NODE_LEAF) {
 324                         int tmp;
 325
 326                         tmp = hfs_bnode_read_u16(node, key_off);
 327                         dprint(DBG_BNODE_MOD, " (%d)", tmp);
 328                 }
 329         }
 330         dprint(DBG_BNODE_MOD, "\n");
 331 }
 332
 333 void hfs_bnode_unlink(struct hfs_bnode *node)
 334 {
 335         struct hfs_btree *tree;
 336         struct hfs_bnode *tmp;
 337         __be32 cnid;
 338
 339         tree = node->tree;
 340         if (node->prev) {
 341                 tmp = hfs_bnode_find(tree, node->prev);
 342                 if (IS_ERR(tmp))
 343                         return;
 344                 tmp->next = node->next;
 345                 cnid = cpu_to_be32(tmp->next);
 346                 hfs_bnode_write(tmp, &cnid, offsetof(struct hfs_bnode_desc, next), 4);
 347                 hfs_bnode_put(tmp);
 348         } else if (node->type == HFS_NODE_LEAF)
 349                 tree->leaf_head = node->next;
 350
 351         if (node->next) {
 352                 tmp = hfs_bnode_find(tree, node->next);
 353                 if (IS_ERR(tmp))
 354                         return;
 355                 tmp->prev = node->prev;
 356                 cnid = cpu_to_be32(tmp->prev);
 357                 hfs_bnode_write(tmp, &cnid, offsetof(struct hfs_bnode_desc, prev), 4);
 358                 hfs_bnode_put(tmp);
 359         } else if (node->type == HFS_NODE_LEAF)
 360                 tree->leaf_tail = node->prev;
 361
 362         // move down?
 363         if (!node->prev && !node->next) {
 364                 printk("hfs_btree_del_level\n");
 365         }
 366         if (!node->parent) {
 367                 tree->root = 0;
 368                 tree->depth = 0;
 369         }
 370         set_bit(HFS_BNODE_DELETED, &node->flags);
 371 }
 372
 373 static inline int hfs_bnode_hash(u32 num)
 374 {
 375         num = (num >> 16) + num;
 376         num += num >> 8;
 377         return num & (NODE_HASH_SIZE - 1);
 378 }
 379
 380 struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
 381 {
 382         struct hfs_bnode *node;
 383
 384         if (cnid >= tree->node_count) {
 385                 printk("HFS+-fs: request for non-existent node %d in B*Tree\n", cnid);
 386                 return NULL;
 387         }
 388
 389         for (node = tree->node_hash[hfs_bnode_hash(cnid)];
 390              node; node = node->next_hash) {
 391                 if (node->this == cnid) {
 392                         return node;
 393                 }
 394         }
 395         return NULL;
 396 }
 397
 398 static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 399 {
 400         struct super_block *sb;
 401         struct hfs_bnode *node, *node2;
 402         struct address_space *mapping;
 403         struct page *page;
 404         int size, block, i, hash;
 405         loff_t off;
 406
 407         if (cnid >= tree->node_count) {
 408                 printk("HFS+-fs: request for non-existent node %d in B*Tree\n", cnid);
 409                 return NULL;
 410         }
 411
 412         sb = tree->inode->i_sb;
 413         size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
 414                 sizeof(struct page *);
 415         node = kmalloc(size, GFP_KERNEL);
 416         if (!node)
 417                 return NULL;
 418         memset(node, 0, size);
 419         node->tree = tree;
 420         node->this = cnid;
 421         set_bit(HFS_BNODE_NEW, &node->flags);
 422         atomic_set(&node->refcnt, 1);
 423         dprint(DBG_BNODE_REFS, "new_node(%d:%d): 1\n",
 424                node->tree->cnid, node->this);
 425         init_waitqueue_head(&node->lock_wq);
 426         spin_lock(&tree->hash_lock);
 427         node2 = hfs_bnode_findhash(tree, cnid);
 428         if (!node2) {
 429                 hash = hfs_bnode_hash(cnid);
 430                 node->next_hash = tree->node_hash[hash];
 431                 tree->node_hash[hash] = node;
 432                 tree->node_hash_cnt++;
 433         } else {
 434                 spin_unlock(&tree->hash_lock);
 435                 kfree(node);
 436                 wait_event(node2->lock_wq, !test_bit(HFS_BNODE_NEW, &node2->flags));
 437                 return node2;
 438         }
 439         spin_unlock(&tree->hash_lock);
 440
 441         mapping = tree->inode->i_mapping;
 442         off = (loff_t)cnid << tree->node_size_shift;
 443         block = off >> PAGE_CACHE_SHIFT;
 444         node->page_offset = off & ~PAGE_CACHE_MASK;
 445         for (i = 0; i < tree->pages_per_bnode; block++, i++) {
 446                 page = read_cache_page(mapping, block, (filler_t *)mapping->a_ops->readpage, NULL);
 447                 if (IS_ERR(page))
 448                         goto fail;
 449                 if (PageError(page)) {
 450                         page_cache_release(page);
 451                         goto fail;
 452                 }
 453 #if !REF_PAGES
 454                 page_cache_release(page);
 455 #endif
 456                 node->page[i] = page;
 457         }
 458
 459         return node;
 460 fail:
 461         set_bit(HFS_BNODE_ERROR, &node->flags);
 462         return node;
 463 }
 464
 465 void hfs_bnode_unhash(struct hfs_bnode *node)
 466 {
 467         struct hfs_bnode **p;
 468
 469         dprint(DBG_BNODE_REFS, "remove_node(%d:%d): %d\n",
 470                 node->tree->cnid, node->this, atomic_read(&node->refcnt));
 471         for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)];
 472              *p && *p != node; p = &(*p)->next_hash)
 473                 ;
 474         if (!*p)
 475                 BUG();
 476         *p = node->next_hash;
 477         node->tree->node_hash_cnt--;
 478 }
 479
 480 /* Load a particular node out of a tree */
 481 struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
 482 {
 483         struct hfs_bnode *node;
 484         struct hfs_bnode_desc *desc;
 485         int i, rec_off, off, next_off;
 486         int entry_size, key_size;
 487
 488         spin_lock(&tree->hash_lock);
 489         node = hfs_bnode_findhash(tree, num);
 490         if (node) {
 491                 hfs_bnode_get(node);
 492                 spin_unlock(&tree->hash_lock);
 493                 wait_event(node->lock_wq, !test_bit(HFS_BNODE_NEW, &node->flags));
 494                 if (test_bit(HFS_BNODE_ERROR, &node->flags))
 495                         goto node_error;
 496                 return node;
 497         }
 498         spin_unlock(&tree->hash_lock);
 499         node = __hfs_bnode_create(tree, num);
 500         if (!node)
 501                 return ERR_PTR(-ENOMEM);
 502         if (test_bit(HFS_BNODE_ERROR, &node->flags))
 503                 goto node_error;
 504         if (!test_bit(HFS_BNODE_NEW, &node->flags))
 505                 return node;
 506
 507         desc = (struct hfs_bnode_desc *)(kmap(node->page[0]) + node->page_offset);
 508         node->prev = be32_to_cpu(desc->prev);
 509         node->next = be32_to_cpu(desc->next);
 510         node->num_recs = be16_to_cpu(desc->num_recs);
 511         node->type = desc->type;
 512         node->height = desc->height;
 513         kunmap(node->page[0]);
 514
 515         switch (node->type) {
 516         case HFS_NODE_HEADER:
 517         case HFS_NODE_MAP:
 518                 if (node->height != 0)
 519                         goto node_error;
 520                 break;
 521         case HFS_NODE_LEAF:
 522                 if (node->height != 1)
 523                         goto node_error;
 524                 break;
 525         case HFS_NODE_INDEX:
 526                 if (node->height <= 1 || node->height > tree->depth)
 527                         goto node_error;
 528                 break;
 529         default:
 530                 goto node_error;
 531         }
 532
 533         rec_off = tree->node_size - 2;
 534         off = hfs_bnode_read_u16(node, rec_off);
 535         if (off != sizeof(struct hfs_bnode_desc))
 536                 goto node_error;
 537         for (i = 1; i <= node->num_recs; off = next_off, i++) {
 538                 rec_off -= 2;
 539                 next_off = hfs_bnode_read_u16(node, rec_off);
 540                 if (next_off <= off ||
 541                     next_off > tree->node_size ||
 542                     next_off & 1)
 543                         goto node_error;
 544                 entry_size = next_off - off;
 545                 if (node->type != HFS_NODE_INDEX &&
 546                     node->type != HFS_NODE_LEAF)
 547                         continue;
 548                 key_size = hfs_bnode_read_u16(node, off) + 2;
 549                 if (key_size >= entry_size || key_size & 1)
 550                         goto node_error;
 551         }
 552         clear_bit(HFS_BNODE_NEW, &node->flags);
 553         wake_up(&node->lock_wq);
 554         return node;
 555
 556 node_error:
 557         set_bit(HFS_BNODE_ERROR, &node->flags);
 558         clear_bit(HFS_BNODE_NEW, &node->flags);
 559         wake_up(&node->lock_wq);
 560         hfs_bnode_put(node);
 561         return ERR_PTR(-EIO);
 562 }
 563
 564 void hfs_bnode_free(struct hfs_bnode *node)
 565 {
 566         //int i;
 567
 568         //for (i = 0; i < node->tree->pages_per_bnode; i++)
 569         //      if (node->page[i])
 570         //              page_cache_release(node->page[i]);
 571         kfree(node);
 572 }
 573
 574 struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num)
 575 {
 576         struct hfs_bnode *node;
 577         struct page **pagep;
 578         int i;
 579
 580         spin_lock(&tree->hash_lock);
 581         node = hfs_bnode_findhash(tree, num);
 582         spin_unlock(&tree->hash_lock);
 583         if (node) {
 584                 printk("new node %u already hashed?\n", num);
 585                 BUG();
 586         }
 587         node = __hfs_bnode_create(tree, num);
 588         if (!node)
 589                 return ERR_PTR(-ENOMEM);
 590         if (test_bit(HFS_BNODE_ERROR, &node->flags)) {
 591                 hfs_bnode_put(node);
 592                 return ERR_PTR(-EIO);
 593         }
 594
 595         pagep = node->page;
 596         memset(kmap(*pagep) + node->page_offset, 0,
 597                min((int)PAGE_CACHE_SIZE, (int)tree->node_size));
 598         set_page_dirty(*pagep);
 599         kunmap(*pagep);
 600         for (i = 1; i < tree->pages_per_bnode; i++) {
 601                 memset(kmap(*++pagep), 0, PAGE_CACHE_SIZE);
 602                 set_page_dirty(*pagep);
 603                 kunmap(*pagep);
 604         }
 605         clear_bit(HFS_BNODE_NEW, &node->flags);
 606         wake_up(&node->lock_wq);
 607
 608         return node;
 609 }
 610
 611 void hfs_bnode_get(struct hfs_bnode *node)
 612 {
 613         if (node) {
 614                 atomic_inc(&node->refcnt);
 615 #if REF_PAGES
 616                 {
 617                 int i;
 618                 for (i = 0; i < node->tree->pages_per_bnode; i++)
 619                         get_page(node->page[i]);
 620                 }
 621 #endif
 622                 dprint(DBG_BNODE_REFS, "get_node(%d:%d): %d\n",
 623                        node->tree->cnid, node->this, atomic_read(&node->refcnt));
 624         }
 625 }
 626
 627 /* Dispose of resources used by a node */
 628 void hfs_bnode_put(struct hfs_bnode *node)
 629 {
 630         if (node) {
 631                 struct hfs_btree *tree = node->tree;
 632                 int i;
 633
 634                 dprint(DBG_BNODE_REFS, "put_node(%d:%d): %d\n",
 635                        node->tree->cnid, node->this, atomic_read(&node->refcnt));
 636                 if (!atomic_read(&node->refcnt))
 637                         BUG();
 638                 if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock)) {
 639 #if REF_PAGES
 640                         for (i = 0; i < tree->pages_per_bnode; i++)
 641                                 put_page(node->page[i]);
 642 #endif
 643                         return;
 644                 }
 645                 for (i = 0; i < tree->pages_per_bnode; i++) {
 646                         if (!node->page[i])
 647                                 continue;
 648                         mark_page_accessed(node->page[i]);
 649 #if REF_PAGES
 650                         put_page(node->page[i]);
 651 #endif
 652                 }
 653
 654                 if (test_bit(HFS_BNODE_DELETED, &node->flags)) {
 655                         hfs_bnode_unhash(node);
 656                         spin_unlock(&tree->hash_lock);
 657                         hfs_bmap_free(node);
 658                         hfs_bnode_free(node);
 659                         return;
 660                 }
 661                 spin_unlock(&tree->hash_lock);
 662         }
 663 }
 664