bnode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/hfsplus/bnode.c
   4  *
   5  * Copyright (C) 2001
   6  * Brad Boyer (flar@allandria.com)
   7  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   8  *
   9  * Handle basic btree node operations
  10  */
  11
  12 #include <linux/string.h>
  13 #include <linux/slab.h>
  14 #include <linux/pagemap.h>
  15 #include <linux/fs.h>
  16 #include <linux/swap.h>
  17
  18 #include "hfsplus_fs.h"
  19 #include "hfsplus_raw.h"
  20
  21 /* Copy a specified range of bytes from the raw data of a node */
  22 void hfs_bnode_read(struct hfs_bnode *node, void *buf, int off, int len)
  23 {
  24         struct page **pagep;
  25         int l;
  26
  27         off += node->page_offset;
  28         pagep = node->page + (off >> PAGE_SHIFT);
  29         off &= ~PAGE_MASK;
  30
  31         l = min_t(int, len, PAGE_SIZE - off);
  32         memcpy_from_page(buf, *pagep, off, l);
  33
  34         while ((len -= l) != 0) {
  35                 buf += l;
  36                 l = min_t(int, len, PAGE_SIZE);
  37                 memcpy_from_page(buf, *++pagep, 0, l);
  38         }
  39 }
  40
  41 u16 hfs_bnode_read_u16(struct hfs_bnode *node, int off)
  42 {
  43         __be16 data;
  44         /* TODO: optimize later... */
  45         hfs_bnode_read(node, &data, off, 2);
  46         return be16_to_cpu(data);
  47 }
  48
  49 u8 hfs_bnode_read_u8(struct hfs_bnode *node, int off)
  50 {
  51         u8 data;
  52         /* TODO: optimize later... */
  53         hfs_bnode_read(node, &data, off, 1);
  54         return data;
  55 }
  56
  57 void hfs_bnode_read_key(struct hfs_bnode *node, void *key, int off)
  58 {
  59         struct hfs_btree *tree;
  60         int key_len;
  61
  62         tree = node->tree;
  63         if (node->type == HFS_NODE_LEAF ||
  64             tree->attributes & HFS_TREE_VARIDXKEYS ||
  65             node->tree->cnid == HFSPLUS_ATTR_CNID)
  66                 key_len = hfs_bnode_read_u16(node, off) + 2;
  67         else
  68                 key_len = tree->max_key_len + 2;
  69
  70         hfs_bnode_read(node, key, off, key_len);
  71 }
  72
  73 void hfs_bnode_write(struct hfs_bnode *node, void *buf, int off, int len)
  74 {
  75         struct page **pagep;
  76         int l;
  77
  78         off += node->page_offset;
  79         pagep = node->page + (off >> PAGE_SHIFT);
  80         off &= ~PAGE_MASK;
  81
  82         l = min_t(int, len, PAGE_SIZE - off);
  83         memcpy_to_page(*pagep, off, buf, l);
  84         set_page_dirty(*pagep);
  85
  86         while ((len -= l) != 0) {
  87                 buf += l;
  88                 l = min_t(int, len, PAGE_SIZE);
  89                 memcpy_to_page(*++pagep, 0, buf, l);
  90                 set_page_dirty(*pagep);
  91         }
  92 }
  93
  94 void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data)
  95 {
  96         __be16 v = cpu_to_be16(data);
  97         /* TODO: optimize later... */
  98         hfs_bnode_write(node, &v, off, 2);
  99 }
 100
 101 void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
 102 {
 103         struct page **pagep;
 104         int l;
 105
 106         off += node->page_offset;
 107         pagep = node->page + (off >> PAGE_SHIFT);
 108         off &= ~PAGE_MASK;
 109
 110         l = min_t(int, len, PAGE_SIZE - off);
 111         memzero_page(*pagep, off, l);
 112         set_page_dirty(*pagep);
 113
 114         while ((len -= l) != 0) {
 115                 l = min_t(int, len, PAGE_SIZE);
 116                 memzero_page(*++pagep, 0, l);
 117                 set_page_dirty(*pagep);
 118         }
 119 }
 120
 121 void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
 122                     struct hfs_bnode *src_node, int src, int len)
 123 {
 124         struct page **src_page, **dst_page;
 125         int l;
 126
 127         hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
 128         if (!len)
 129                 return;
 130         src += src_node->page_offset;
 131         dst += dst_node->page_offset;
 132         src_page = src_node->page + (src >> PAGE_SHIFT);
 133         src &= ~PAGE_MASK;
 134         dst_page = dst_node->page + (dst >> PAGE_SHIFT);
 135         dst &= ~PAGE_MASK;
 136
 137         if (src == dst) {
 138                 l = min_t(int, len, PAGE_SIZE - src);
 139                 memcpy_page(*dst_page, src, *src_page, src, l);
 140                 set_page_dirty(*dst_page);
 141
 142                 while ((len -= l) != 0) {
 143                         l = min_t(int, len, PAGE_SIZE);
 144                         memcpy_page(*++dst_page, 0, *++src_page, 0, l);
 145                         set_page_dirty(*dst_page);
 146                 }
 147         } else {
 148                 void *src_ptr, *dst_ptr;
 149
 150                 do {
 151                         dst_ptr = kmap_local_page(*dst_page) + dst;
 152                         src_ptr = kmap_local_page(*src_page) + src;
 153                         if (PAGE_SIZE - src < PAGE_SIZE - dst) {
 154                                 l = PAGE_SIZE - src;
 155                                 src = 0;
 156                                 dst += l;
 157                         } else {
 158                                 l = PAGE_SIZE - dst;
 159                                 src += l;
 160                                 dst = 0;
 161                         }
 162                         l = min(len, l);
 163                         memcpy(dst_ptr, src_ptr, l);
 164                         kunmap_local(src_ptr);
 165                         set_page_dirty(*dst_page);
 166                         kunmap_local(dst_ptr);
 167                         if (!dst)
 168                                 dst_page++;
 169                         else
 170                                 src_page++;
 171                 } while ((len -= l));
 172         }
 173 }
 174
 175 void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len)
 176 {
 177         struct page **src_page, **dst_page;
 178         void *src_ptr, *dst_ptr;
 179         int l;
 180
 181         hfs_dbg(BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len);
 182         if (!len)
 183                 return;
 184         src += node->page_offset;
 185         dst += node->page_offset;
 186         if (dst > src) {
 187                 src += len - 1;
 188                 src_page = node->page + (src >> PAGE_SHIFT);
 189                 src = (src & ~PAGE_MASK) + 1;
 190                 dst += len - 1;
 191                 dst_page = node->page + (dst >> PAGE_SHIFT);
 192                 dst = (dst & ~PAGE_MASK) + 1;
 193
 194                 if (src == dst) {
 195                         while (src < len) {
 196                                 dst_ptr = kmap_local_page(*dst_page);
 197                                 src_ptr = kmap_local_page(*src_page);
 198                                 memmove(dst_ptr, src_ptr, src);
 199                                 kunmap_local(src_ptr);
 200                                 set_page_dirty(*dst_page);
 201                                 kunmap_local(dst_ptr);
 202                                 len -= src;
 203                                 src = PAGE_SIZE;
 204                                 src_page--;
 205                                 dst_page--;
 206                         }
 207                         src -= len;
 208                         dst_ptr = kmap_local_page(*dst_page);
 209                         src_ptr = kmap_local_page(*src_page);
 210                         memmove(dst_ptr + src, src_ptr + src, len);
 211                         kunmap_local(src_ptr);
 212                         set_page_dirty(*dst_page);
 213                         kunmap_local(dst_ptr);
 214                 } else {
 215                         do {
 216                                 dst_ptr = kmap_local_page(*dst_page) + dst;
 217                                 src_ptr = kmap_local_page(*src_page) + src;
 218                                 if (src < dst) {
 219                                         l = src;
 220                                         src = PAGE_SIZE;
 221                                         dst -= l;
 222                                 } else {
 223                                         l = dst;
 224                                         src -= l;
 225                                         dst = PAGE_SIZE;
 226                                 }
 227                                 l = min(len, l);
 228                                 memmove(dst_ptr - l, src_ptr - l, l);
 229                                 kunmap_local(src_ptr);
 230                                 set_page_dirty(*dst_page);
 231                                 kunmap_local(dst_ptr);
 232                                 if (dst == PAGE_SIZE)
 233                                         dst_page--;
 234                                 else
 235                                         src_page--;
 236                         } while ((len -= l));
 237                 }
 238         } else {
 239                 src_page = node->page + (src >> PAGE_SHIFT);
 240                 src &= ~PAGE_MASK;
 241                 dst_page = node->page + (dst >> PAGE_SHIFT);
 242                 dst &= ~PAGE_MASK;
 243
 244                 if (src == dst) {
 245                         l = min_t(int, len, PAGE_SIZE - src);
 246
 247                         dst_ptr = kmap_local_page(*dst_page) + src;
 248                         src_ptr = kmap_local_page(*src_page) + src;
 249                         memmove(dst_ptr, src_ptr, l);
 250                         kunmap_local(src_ptr);
 251                         set_page_dirty(*dst_page);
 252                         kunmap_local(dst_ptr);
 253
 254                         while ((len -= l) != 0) {
 255                                 l = min_t(int, len, PAGE_SIZE);
 256                                 dst_ptr = kmap_local_page(*++dst_page);
 257                                 src_ptr = kmap_local_page(*++src_page);
 258                                 memmove(dst_ptr, src_ptr, l);
 259                                 kunmap_local(src_ptr);
 260                                 set_page_dirty(*dst_page);
 261                                 kunmap_local(dst_ptr);
 262                         }
 263                 } else {
 264                         do {
 265                                 dst_ptr = kmap_local_page(*dst_page) + dst;
 266                                 src_ptr = kmap_local_page(*src_page) + src;
 267                                 if (PAGE_SIZE - src <
 268                                                 PAGE_SIZE - dst) {
 269                                         l = PAGE_SIZE - src;
 270                                         src = 0;
 271                                         dst += l;
 272                                 } else {
 273                                         l = PAGE_SIZE - dst;
 274                                         src += l;
 275                                         dst = 0;
 276                                 }
 277                                 l = min(len, l);
 278                                 memmove(dst_ptr, src_ptr, l);
 279                                 kunmap_local(src_ptr);
 280                                 set_page_dirty(*dst_page);
 281                                 kunmap_local(dst_ptr);
 282                                 if (!dst)
 283                                         dst_page++;
 284                                 else
 285                                         src_page++;
 286                         } while ((len -= l));
 287                 }
 288         }
 289 }
 290
 291 void hfs_bnode_dump(struct hfs_bnode *node)
 292 {
 293         struct hfs_bnode_desc desc;
 294         __be32 cnid;
 295         int i, off, key_off;
 296
 297         hfs_dbg(BNODE_MOD, "bnode: %d\n", node->this);
 298         hfs_bnode_read(node, &desc, 0, sizeof(desc));
 299         hfs_dbg(BNODE_MOD, "%d, %d, %d, %d, %d\n",
 300                 be32_to_cpu(desc.next), be32_to_cpu(desc.prev),
 301                 desc.type, desc.height, be16_to_cpu(desc.num_recs));
 302
 303         off = node->tree->node_size - 2;
 304         for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) {
 305                 key_off = hfs_bnode_read_u16(node, off);
 306                 hfs_dbg(BNODE_MOD, " %d", key_off);
 307                 if (i && node->type == HFS_NODE_INDEX) {
 308                         int tmp;
 309
 310                         if (node->tree->attributes & HFS_TREE_VARIDXKEYS ||
 311                                         node->tree->cnid == HFSPLUS_ATTR_CNID)
 312                                 tmp = hfs_bnode_read_u16(node, key_off) + 2;
 313                         else
 314                                 tmp = node->tree->max_key_len + 2;
 315                         hfs_dbg_cont(BNODE_MOD, " (%d", tmp);
 316                         hfs_bnode_read(node, &cnid, key_off + tmp, 4);
 317                         hfs_dbg_cont(BNODE_MOD, ",%d)", be32_to_cpu(cnid));
 318                 } else if (i && node->type == HFS_NODE_LEAF) {
 319                         int tmp;
 320
 321                         tmp = hfs_bnode_read_u16(node, key_off);
 322                         hfs_dbg_cont(BNODE_MOD, " (%d)", tmp);
 323                 }
 324         }
 325         hfs_dbg_cont(BNODE_MOD, "\n");
 326 }
 327
 328 void hfs_bnode_unlink(struct hfs_bnode *node)
 329 {
 330         struct hfs_btree *tree;
 331         struct hfs_bnode *tmp;
 332         __be32 cnid;
 333
 334         tree = node->tree;
 335         if (node->prev) {
 336                 tmp = hfs_bnode_find(tree, node->prev);
 337                 if (IS_ERR(tmp))
 338                         return;
 339                 tmp->next = node->next;
 340                 cnid = cpu_to_be32(tmp->next);
 341                 hfs_bnode_write(tmp, &cnid,
 342                         offsetof(struct hfs_bnode_desc, next), 4);
 343                 hfs_bnode_put(tmp);
 344         } else if (node->type == HFS_NODE_LEAF)
 345                 tree->leaf_head = node->next;
 346
 347         if (node->next) {
 348                 tmp = hfs_bnode_find(tree, node->next);
 349                 if (IS_ERR(tmp))
 350                         return;
 351                 tmp->prev = node->prev;
 352                 cnid = cpu_to_be32(tmp->prev);
 353                 hfs_bnode_write(tmp, &cnid,
 354                         offsetof(struct hfs_bnode_desc, prev), 4);
 355                 hfs_bnode_put(tmp);
 356         } else if (node->type == HFS_NODE_LEAF)
 357                 tree->leaf_tail = node->prev;
 358
 359         /* move down? */
 360         if (!node->prev && !node->next)
 361                 hfs_dbg(BNODE_MOD, "hfs_btree_del_level\n");
 362         if (!node->parent) {
 363                 tree->root = 0;
 364                 tree->depth = 0;
 365         }
 366         set_bit(HFS_BNODE_DELETED, &node->flags);
 367 }
 368
 369 static inline int hfs_bnode_hash(u32 num)
 370 {
 371         num = (num >> 16) + num;
 372         num += num >> 8;
 373         return num & (NODE_HASH_SIZE - 1);
 374 }
 375
 376 struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
 377 {
 378         struct hfs_bnode *node;
 379
 380         if (cnid >= tree->node_count) {
 381                 pr_err("request for non-existent node %d in B*Tree\n",
 382                        cnid);
 383                 return NULL;
 384         }
 385
 386         for (node = tree->node_hash[hfs_bnode_hash(cnid)];
 387                         node; node = node->next_hash)
 388                 if (node->this == cnid)
 389                         return node;
 390         return NULL;
 391 }
 392
 393 static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 394 {
 395         struct hfs_bnode *node, *node2;
 396         struct address_space *mapping;
 397         struct page *page;
 398         int size, block, i, hash;
 399         loff_t off;
 400
 401         if (cnid >= tree->node_count) {
 402                 pr_err("request for non-existent node %d in B*Tree\n",
 403                        cnid);
 404                 return NULL;
 405         }
 406
 407         size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
 408                 sizeof(struct page *);
 409         node = kzalloc(size, GFP_KERNEL);
 410         if (!node)
 411                 return NULL;
 412         node->tree = tree;
 413         node->this = cnid;
 414         set_bit(HFS_BNODE_NEW, &node->flags);
 415         atomic_set(&node->refcnt, 1);
 416         hfs_dbg(BNODE_REFS, "new_node(%d:%d): 1\n",
 417                 node->tree->cnid, node->this);
 418         init_waitqueue_head(&node->lock_wq);
 419         spin_lock(&tree->hash_lock);
 420         node2 = hfs_bnode_findhash(tree, cnid);
 421         if (!node2) {
 422                 hash = hfs_bnode_hash(cnid);
 423                 node->next_hash = tree->node_hash[hash];
 424                 tree->node_hash[hash] = node;
 425                 tree->node_hash_cnt++;
 426         } else {
 427                 spin_unlock(&tree->hash_lock);
 428                 kfree(node);
 429                 wait_event(node2->lock_wq,
 430                         !test_bit(HFS_BNODE_NEW, &node2->flags));
 431                 return node2;
 432         }
 433         spin_unlock(&tree->hash_lock);
 434
 435         mapping = tree->inode->i_mapping;
 436         off = (loff_t)cnid << tree->node_size_shift;
 437         block = off >> PAGE_SHIFT;
 438         node->page_offset = off & ~PAGE_MASK;
 439         for (i = 0; i < tree->pages_per_bnode; block++, i++) {
 440                 page = read_mapping_page(mapping, block, NULL);
 441                 if (IS_ERR(page))
 442                         goto fail;
 443                 node->page[i] = page;
 444         }
 445
 446         return node;
 447 fail:
 448         set_bit(HFS_BNODE_ERROR, &node->flags);
 449         return node;
 450 }
 451
 452 void hfs_bnode_unhash(struct hfs_bnode *node)
 453 {
 454         struct hfs_bnode **p;
 455
 456         hfs_dbg(BNODE_REFS, "remove_node(%d:%d): %d\n",
 457                 node->tree->cnid, node->this, atomic_read(&node->refcnt));
 458         for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)];
 459              *p && *p != node; p = &(*p)->next_hash)
 460                 ;
 461         BUG_ON(!*p);
 462         *p = node->next_hash;
 463         node->tree->node_hash_cnt--;
 464 }
 465
 466 /* Load a particular node out of a tree */
 467 struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
 468 {
 469         struct hfs_bnode *node;
 470         struct hfs_bnode_desc *desc;
 471         int i, rec_off, off, next_off;
 472         int entry_size, key_size;
 473
 474         spin_lock(&tree->hash_lock);
 475         node = hfs_bnode_findhash(tree, num);
 476         if (node) {
 477                 hfs_bnode_get(node);
 478                 spin_unlock(&tree->hash_lock);
 479                 wait_event(node->lock_wq,
 480                         !test_bit(HFS_BNODE_NEW, &node->flags));
 481                 if (test_bit(HFS_BNODE_ERROR, &node->flags))
 482                         goto node_error;
 483                 return node;
 484         }
 485         spin_unlock(&tree->hash_lock);
 486         node = __hfs_bnode_create(tree, num);
 487         if (!node)
 488                 return ERR_PTR(-ENOMEM);
 489         if (test_bit(HFS_BNODE_ERROR, &node->flags))
 490                 goto node_error;
 491         if (!test_bit(HFS_BNODE_NEW, &node->flags))
 492                 return node;
 493
 494         desc = (struct hfs_bnode_desc *)(kmap_local_page(node->page[0]) +
 495                                                          node->page_offset);
 496         node->prev = be32_to_cpu(desc->prev);
 497         node->next = be32_to_cpu(desc->next);
 498         node->num_recs = be16_to_cpu(desc->num_recs);
 499         node->type = desc->type;
 500         node->height = desc->height;
 501         kunmap_local(desc);
 502
 503         switch (node->type) {
 504         case HFS_NODE_HEADER:
 505         case HFS_NODE_MAP:
 506                 if (node->height != 0)
 507                         goto node_error;
 508                 break;
 509         case HFS_NODE_LEAF:
 510                 if (node->height != 1)
 511                         goto node_error;
 512                 break;
 513         case HFS_NODE_INDEX:
 514                 if (node->height <= 1 || node->height > tree->depth)
 515                         goto node_error;
 516                 break;
 517         default:
 518                 goto node_error;
 519         }
 520
 521         rec_off = tree->node_size - 2;
 522         off = hfs_bnode_read_u16(node, rec_off);
 523         if (off != sizeof(struct hfs_bnode_desc))
 524                 goto node_error;
 525         for (i = 1; i <= node->num_recs; off = next_off, i++) {
 526                 rec_off -= 2;
 527                 next_off = hfs_bnode_read_u16(node, rec_off);
 528                 if (next_off <= off ||
 529                     next_off > tree->node_size ||
 530                     next_off & 1)
 531                         goto node_error;
 532                 entry_size = next_off - off;
 533                 if (node->type != HFS_NODE_INDEX &&
 534                     node->type != HFS_NODE_LEAF)
 535                         continue;
 536                 key_size = hfs_bnode_read_u16(node, off) + 2;
 537                 if (key_size >= entry_size || key_size & 1)
 538                         goto node_error;
 539         }
 540         clear_bit(HFS_BNODE_NEW, &node->flags);
 541         wake_up(&node->lock_wq);
 542         return node;
 543
 544 node_error:
 545         set_bit(HFS_BNODE_ERROR, &node->flags);
 546         clear_bit(HFS_BNODE_NEW, &node->flags);
 547         wake_up(&node->lock_wq);
 548         hfs_bnode_put(node);
 549         return ERR_PTR(-EIO);
 550 }
 551
 552 void hfs_bnode_free(struct hfs_bnode *node)
 553 {
 554         int i;
 555
 556         for (i = 0; i < node->tree->pages_per_bnode; i++)
 557                 if (node->page[i])
 558                         put_page(node->page[i]);
 559         kfree(node);
 560 }
 561
 562 struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num)
 563 {
 564         struct hfs_bnode *node;
 565         struct page **pagep;
 566         int i;
 567
 568         spin_lock(&tree->hash_lock);
 569         node = hfs_bnode_findhash(tree, num);
 570         spin_unlock(&tree->hash_lock);
 571         if (node) {
 572                 pr_crit("new node %u already hashed?\n", num);
 573                 WARN_ON(1);
 574                 return node;
 575         }
 576         node = __hfs_bnode_create(tree, num);
 577         if (!node)
 578                 return ERR_PTR(-ENOMEM);
 579         if (test_bit(HFS_BNODE_ERROR, &node->flags)) {
 580                 hfs_bnode_put(node);
 581                 return ERR_PTR(-EIO);
 582         }
 583
 584         pagep = node->page;
 585         memzero_page(*pagep, node->page_offset,
 586                      min_t(int, PAGE_SIZE, tree->node_size));
 587         set_page_dirty(*pagep);
 588         for (i = 1; i < tree->pages_per_bnode; i++) {
 589                 memzero_page(*++pagep, 0, PAGE_SIZE);
 590                 set_page_dirty(*pagep);
 591         }
 592         clear_bit(HFS_BNODE_NEW, &node->flags);
 593         wake_up(&node->lock_wq);
 594
 595         return node;
 596 }
 597
 598 void hfs_bnode_get(struct hfs_bnode *node)
 599 {
 600         if (node) {
 601                 atomic_inc(&node->refcnt);
 602                 hfs_dbg(BNODE_REFS, "get_node(%d:%d): %d\n",
 603                         node->tree->cnid, node->this,
 604                         atomic_read(&node->refcnt));
 605         }
 606 }
 607
 608 /* Dispose of resources used by a node */
 609 void hfs_bnode_put(struct hfs_bnode *node)
 610 {
 611         if (node) {
 612                 struct hfs_btree *tree = node->tree;
 613                 int i;
 614
 615                 hfs_dbg(BNODE_REFS, "put_node(%d:%d): %d\n",
 616                         node->tree->cnid, node->this,
 617                         atomic_read(&node->refcnt));
 618                 BUG_ON(!atomic_read(&node->refcnt));
 619                 if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock))
 620                         return;
 621                 for (i = 0; i < tree->pages_per_bnode; i++) {
 622                         if (!node->page[i])
 623                                 continue;
 624                         mark_page_accessed(node->page[i]);
 625                 }
 626
 627                 if (test_bit(HFS_BNODE_DELETED, &node->flags)) {
 628                         hfs_bnode_unhash(node);
 629                         spin_unlock(&tree->hash_lock);
 630                         if (hfs_bnode_need_zeroout(tree))
 631                                 hfs_bnode_clear(node, 0, tree->node_size);
 632                         hfs_bmap_free(node);
 633                         hfs_bnode_free(node);
 634                         return;
 635                 }
 636                 spin_unlock(&tree->hash_lock);
 637         }
 638 }
 639
 640 /*
 641  * Unused nodes have to be zeroed if this is the catalog tree and
 642  * a corresponding flag in the volume header is set.
 643  */
 644 bool hfs_bnode_need_zeroout(struct hfs_btree *tree)
 645 {
 646         struct super_block *sb = tree->inode->i_sb;
 647         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 648         const u32 volume_attr = be32_to_cpu(sbi->s_vhdr->attributes);
 649
 650         return tree->cnid == HFSPLUS_CAT_CNID &&
 651                 volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX;
 652 }