Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
| 17 | #include "hfsplus_fs.h" |
| 18 | #include "hfsplus_raw.h" |
| 19 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | // 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 | // 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 | 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_CACHE_SHIFT); |
| 80 | off &= ~PAGE_CACHE_MASK; |
| 81 | |
| 82 | l = min(len, (int)PAGE_CACHE_SIZE - off); |
| 83 | memcpy(kmap(*pagep) + off, buf, l); |
| 84 | set_page_dirty(*pagep); |
| 85 | kunmap(*pagep); |
| 86 | |
| 87 | while ((len -= l) != 0) { |
| 88 | buf += l; |
| 89 | l = min(len, (int)PAGE_CACHE_SIZE); |
| 90 | memcpy(kmap(*++pagep), buf, l); |
| 91 | set_page_dirty(*pagep); |
| 92 | kunmap(*pagep); |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | void hfs_bnode_write_u16(struct hfs_bnode *node, int off, u16 data) |
| 97 | { |
| 98 | __be16 v = cpu_to_be16(data); |
| 99 | // optimize later... |
| 100 | hfs_bnode_write(node, &v, off, 2); |
| 101 | } |
| 102 | |
| 103 | void hfs_bnode_clear(struct hfs_bnode *node, int off, int len) |
| 104 | { |
| 105 | struct page **pagep; |
| 106 | int l; |
| 107 | |
| 108 | off += node->page_offset; |
| 109 | pagep = node->page + (off >> PAGE_CACHE_SHIFT); |
| 110 | off &= ~PAGE_CACHE_MASK; |
| 111 | |
| 112 | l = min(len, (int)PAGE_CACHE_SIZE - off); |
| 113 | memset(kmap(*pagep) + off, 0, l); |
| 114 | set_page_dirty(*pagep); |
| 115 | kunmap(*pagep); |
| 116 | |
| 117 | while ((len -= l) != 0) { |
| 118 | l = min(len, (int)PAGE_CACHE_SIZE); |
| 119 | memset(kmap(*++pagep), 0, l); |
| 120 | set_page_dirty(*pagep); |
| 121 | kunmap(*pagep); |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst, |
| 126 | struct hfs_bnode *src_node, int src, int len) |
| 127 | { |
| 128 | struct hfs_btree *tree; |
| 129 | struct page **src_page, **dst_page; |
| 130 | int l; |
| 131 | |
| 132 | dprint(DBG_BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len); |
| 133 | if (!len) |
| 134 | return; |
| 135 | tree = src_node->tree; |
| 136 | src += src_node->page_offset; |
| 137 | dst += dst_node->page_offset; |
| 138 | src_page = src_node->page + (src >> PAGE_CACHE_SHIFT); |
| 139 | src &= ~PAGE_CACHE_MASK; |
| 140 | dst_page = dst_node->page + (dst >> PAGE_CACHE_SHIFT); |
| 141 | dst &= ~PAGE_CACHE_MASK; |
| 142 | |
| 143 | if (src == dst) { |
| 144 | l = min(len, (int)PAGE_CACHE_SIZE - src); |
| 145 | memcpy(kmap(*dst_page) + src, kmap(*src_page) + src, l); |
| 146 | kunmap(*src_page); |
| 147 | set_page_dirty(*dst_page); |
| 148 | kunmap(*dst_page); |
| 149 | |
| 150 | while ((len -= l) != 0) { |
| 151 | l = min(len, (int)PAGE_CACHE_SIZE); |
| 152 | memcpy(kmap(*++dst_page), kmap(*++src_page), l); |
| 153 | kunmap(*src_page); |
| 154 | set_page_dirty(*dst_page); |
| 155 | kunmap(*dst_page); |
| 156 | } |
| 157 | } else { |
| 158 | void *src_ptr, *dst_ptr; |
| 159 | |
| 160 | do { |
| 161 | src_ptr = kmap(*src_page) + src; |
| 162 | dst_ptr = kmap(*dst_page) + dst; |
| 163 | if (PAGE_CACHE_SIZE - src < PAGE_CACHE_SIZE - dst) { |
| 164 | l = PAGE_CACHE_SIZE - src; |
| 165 | src = 0; |
| 166 | dst += l; |
| 167 | } else { |
| 168 | l = PAGE_CACHE_SIZE - dst; |
| 169 | src += l; |
| 170 | dst = 0; |
| 171 | } |
| 172 | l = min(len, l); |
| 173 | memcpy(dst_ptr, src_ptr, l); |
| 174 | kunmap(*src_page); |
| 175 | set_page_dirty(*dst_page); |
| 176 | kunmap(*dst_page); |
| 177 | if (!dst) |
| 178 | dst_page++; |
| 179 | else |
| 180 | src_page++; |
| 181 | } while ((len -= l)); |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | void hfs_bnode_move(struct hfs_bnode *node, int dst, int src, int len) |
| 186 | { |
| 187 | struct page **src_page, **dst_page; |
| 188 | int l; |
| 189 | |
| 190 | dprint(DBG_BNODE_MOD, "movebytes: %u,%u,%u\n", dst, src, len); |
| 191 | if (!len) |
| 192 | return; |
| 193 | src += node->page_offset; |
| 194 | dst += node->page_offset; |
| 195 | if (dst > src) { |
| 196 | src += len - 1; |
| 197 | src_page = node->page + (src >> PAGE_CACHE_SHIFT); |
| 198 | src = (src & ~PAGE_CACHE_MASK) + 1; |
| 199 | dst += len - 1; |
| 200 | dst_page = node->page + (dst >> PAGE_CACHE_SHIFT); |
| 201 | dst = (dst & ~PAGE_CACHE_MASK) + 1; |
| 202 | |
| 203 | if (src == dst) { |
| 204 | while (src < len) { |
| 205 | memmove(kmap(*dst_page), kmap(*src_page), src); |
| 206 | kunmap(*src_page); |
| 207 | set_page_dirty(*dst_page); |
| 208 | kunmap(*dst_page); |
| 209 | len -= src; |
| 210 | src = PAGE_CACHE_SIZE; |
| 211 | src_page--; |
| 212 | dst_page--; |
| 213 | } |
| 214 | src -= len; |
| 215 | memmove(kmap(*dst_page) + src, kmap(*src_page) + src, len); |
| 216 | kunmap(*src_page); |
| 217 | set_page_dirty(*dst_page); |
| 218 | kunmap(*dst_page); |
| 219 | } else { |
| 220 | void *src_ptr, *dst_ptr; |
| 221 | |
| 222 | do { |
| 223 | src_ptr = kmap(*src_page) + src; |
| 224 | dst_ptr = kmap(*dst_page) + dst; |
| 225 | if (src < dst) { |
| 226 | l = src; |
| 227 | src = PAGE_CACHE_SIZE; |
| 228 | dst -= l; |
| 229 | } else { |
| 230 | l = dst; |
| 231 | src -= l; |
| 232 | dst = PAGE_CACHE_SIZE; |
| 233 | } |
| 234 | l = min(len, l); |
| 235 | memmove(dst_ptr - l, src_ptr - l, l); |
| 236 | kunmap(*src_page); |
| 237 | set_page_dirty(*dst_page); |
| 238 | kunmap(*dst_page); |
| 239 | if (dst == PAGE_CACHE_SIZE) |
| 240 | dst_page--; |
| 241 | else |
| 242 | src_page--; |
| 243 | } while ((len -= l)); |
| 244 | } |
| 245 | } else { |
| 246 | src_page = node->page + (src >> PAGE_CACHE_SHIFT); |
| 247 | src &= ~PAGE_CACHE_MASK; |
| 248 | dst_page = node->page + (dst >> PAGE_CACHE_SHIFT); |
| 249 | dst &= ~PAGE_CACHE_MASK; |
| 250 | |
| 251 | if (src == dst) { |
| 252 | l = min(len, (int)PAGE_CACHE_SIZE - src); |
| 253 | memmove(kmap(*dst_page) + src, kmap(*src_page) + src, l); |
| 254 | kunmap(*src_page); |
| 255 | set_page_dirty(*dst_page); |
| 256 | kunmap(*dst_page); |
| 257 | |
| 258 | while ((len -= l) != 0) { |
| 259 | l = min(len, (int)PAGE_CACHE_SIZE); |
| 260 | memmove(kmap(*++dst_page), kmap(*++src_page), l); |
| 261 | kunmap(*src_page); |
| 262 | set_page_dirty(*dst_page); |
| 263 | kunmap(*dst_page); |
| 264 | } |
| 265 | } else { |
| 266 | void *src_ptr, *dst_ptr; |
| 267 | |
| 268 | do { |
| 269 | src_ptr = kmap(*src_page) + src; |
| 270 | dst_ptr = kmap(*dst_page) + dst; |
| 271 | if (PAGE_CACHE_SIZE - src < PAGE_CACHE_SIZE - dst) { |
| 272 | l = PAGE_CACHE_SIZE - src; |
| 273 | src = 0; |
| 274 | dst += l; |
| 275 | } else { |
| 276 | l = PAGE_CACHE_SIZE - dst; |
| 277 | src += l; |
| 278 | dst = 0; |
| 279 | } |
| 280 | l = min(len, l); |
| 281 | memmove(dst_ptr, src_ptr, l); |
| 282 | kunmap(*src_page); |
| 283 | set_page_dirty(*dst_page); |
| 284 | kunmap(*dst_page); |
| 285 | if (!dst) |
| 286 | dst_page++; |
| 287 | else |
| 288 | src_page++; |
| 289 | } while ((len -= l)); |
| 290 | } |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | void hfs_bnode_dump(struct hfs_bnode *node) |
| 295 | { |
| 296 | struct hfs_bnode_desc desc; |
| 297 | __be32 cnid; |
| 298 | int i, off, key_off; |
| 299 | |
| 300 | dprint(DBG_BNODE_MOD, "bnode: %d\n", node->this); |
| 301 | hfs_bnode_read(node, &desc, 0, sizeof(desc)); |
| 302 | dprint(DBG_BNODE_MOD, "%d, %d, %d, %d, %d\n", |
| 303 | be32_to_cpu(desc.next), be32_to_cpu(desc.prev), |
| 304 | desc.type, desc.height, be16_to_cpu(desc.num_recs)); |
| 305 | |
| 306 | off = node->tree->node_size - 2; |
| 307 | for (i = be16_to_cpu(desc.num_recs); i >= 0; off -= 2, i--) { |
| 308 | key_off = hfs_bnode_read_u16(node, off); |
| 309 | dprint(DBG_BNODE_MOD, " %d", key_off); |
| 310 | if (i && node->type == HFS_NODE_INDEX) { |
| 311 | int tmp; |
| 312 | |
| 313 | if (node->tree->attributes & HFS_TREE_VARIDXKEYS) |
| 314 | tmp = hfs_bnode_read_u16(node, key_off) + 2; |
| 315 | else |
| 316 | tmp = node->tree->max_key_len + 2; |
| 317 | dprint(DBG_BNODE_MOD, " (%d", tmp); |
| 318 | hfs_bnode_read(node, &cnid, key_off + tmp, 4); |
| 319 | dprint(DBG_BNODE_MOD, ",%d)", be32_to_cpu(cnid)); |
| 320 | } else if (i && node->type == HFS_NODE_LEAF) { |
| 321 | int tmp; |
| 322 | |
| 323 | tmp = hfs_bnode_read_u16(node, key_off); |
| 324 | dprint(DBG_BNODE_MOD, " (%d)", tmp); |
| 325 | } |
| 326 | } |
| 327 | dprint(DBG_BNODE_MOD, "\n"); |
| 328 | } |
| 329 | |
| 330 | void hfs_bnode_unlink(struct hfs_bnode *node) |
| 331 | { |
| 332 | struct hfs_btree *tree; |
| 333 | struct hfs_bnode *tmp; |
| 334 | __be32 cnid; |
| 335 | |
| 336 | tree = node->tree; |
| 337 | if (node->prev) { |
| 338 | tmp = hfs_bnode_find(tree, node->prev); |
| 339 | if (IS_ERR(tmp)) |
| 340 | return; |
| 341 | tmp->next = node->next; |
| 342 | cnid = cpu_to_be32(tmp->next); |
| 343 | hfs_bnode_write(tmp, &cnid, offsetof(struct hfs_bnode_desc, next), 4); |
| 344 | hfs_bnode_put(tmp); |
| 345 | } else if (node->type == HFS_NODE_LEAF) |
| 346 | tree->leaf_head = node->next; |
| 347 | |
| 348 | if (node->next) { |
| 349 | tmp = hfs_bnode_find(tree, node->next); |
| 350 | if (IS_ERR(tmp)) |
| 351 | return; |
| 352 | tmp->prev = node->prev; |
| 353 | cnid = cpu_to_be32(tmp->prev); |
| 354 | hfs_bnode_write(tmp, &cnid, 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) { |
Roman Zippel | 634725a | 2006-01-18 17:43:05 -0800 | [diff] [blame] | 361 | printk(KERN_DEBUG "hfs_btree_del_level\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | } |
| 363 | if (!node->parent) { |
| 364 | tree->root = 0; |
| 365 | tree->depth = 0; |
| 366 | } |
| 367 | set_bit(HFS_BNODE_DELETED, &node->flags); |
| 368 | } |
| 369 | |
| 370 | static inline int hfs_bnode_hash(u32 num) |
| 371 | { |
| 372 | num = (num >> 16) + num; |
| 373 | num += num >> 8; |
| 374 | return num & (NODE_HASH_SIZE - 1); |
| 375 | } |
| 376 | |
| 377 | struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid) |
| 378 | { |
| 379 | struct hfs_bnode *node; |
| 380 | |
| 381 | if (cnid >= tree->node_count) { |
Roman Zippel | 634725a | 2006-01-18 17:43:05 -0800 | [diff] [blame] | 382 | printk(KERN_ERR "hfs: request for non-existent node %d in B*Tree\n", cnid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | } |
| 391 | } |
| 392 | return NULL; |
| 393 | } |
| 394 | |
| 395 | static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid) |
| 396 | { |
| 397 | struct super_block *sb; |
| 398 | struct hfs_bnode *node, *node2; |
| 399 | struct address_space *mapping; |
| 400 | struct page *page; |
| 401 | int size, block, i, hash; |
| 402 | loff_t off; |
| 403 | |
| 404 | if (cnid >= tree->node_count) { |
Roman Zippel | 634725a | 2006-01-18 17:43:05 -0800 | [diff] [blame] | 405 | printk(KERN_ERR "hfs: request for non-existent node %d in B*Tree\n", cnid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | return NULL; |
| 407 | } |
| 408 | |
| 409 | sb = tree->inode->i_sb; |
| 410 | size = sizeof(struct hfs_bnode) + tree->pages_per_bnode * |
| 411 | sizeof(struct page *); |
Panagiotis Issaris | f8314dc | 2006-09-27 01:49:37 -0700 | [diff] [blame^] | 412 | node = kzalloc(size, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | if (!node) |
| 414 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | node->tree = tree; |
| 416 | node->this = cnid; |
| 417 | set_bit(HFS_BNODE_NEW, &node->flags); |
| 418 | atomic_set(&node->refcnt, 1); |
| 419 | dprint(DBG_BNODE_REFS, "new_node(%d:%d): 1\n", |
| 420 | node->tree->cnid, node->this); |
| 421 | init_waitqueue_head(&node->lock_wq); |
| 422 | spin_lock(&tree->hash_lock); |
| 423 | node2 = hfs_bnode_findhash(tree, cnid); |
| 424 | if (!node2) { |
| 425 | hash = hfs_bnode_hash(cnid); |
| 426 | node->next_hash = tree->node_hash[hash]; |
| 427 | tree->node_hash[hash] = node; |
| 428 | tree->node_hash_cnt++; |
| 429 | } else { |
| 430 | spin_unlock(&tree->hash_lock); |
| 431 | kfree(node); |
| 432 | wait_event(node2->lock_wq, !test_bit(HFS_BNODE_NEW, &node2->flags)); |
| 433 | return node2; |
| 434 | } |
| 435 | spin_unlock(&tree->hash_lock); |
| 436 | |
| 437 | mapping = tree->inode->i_mapping; |
| 438 | off = (loff_t)cnid << tree->node_size_shift; |
| 439 | block = off >> PAGE_CACHE_SHIFT; |
| 440 | node->page_offset = off & ~PAGE_CACHE_MASK; |
| 441 | for (i = 0; i < tree->pages_per_bnode; block++, i++) { |
Pekka Enberg | 090d2b1 | 2006-06-23 02:05:08 -0700 | [diff] [blame] | 442 | page = read_mapping_page(mapping, block, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | if (IS_ERR(page)) |
| 444 | goto fail; |
| 445 | if (PageError(page)) { |
| 446 | page_cache_release(page); |
| 447 | goto fail; |
| 448 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | page_cache_release(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | node->page[i] = page; |
| 451 | } |
| 452 | |
| 453 | return node; |
| 454 | fail: |
| 455 | set_bit(HFS_BNODE_ERROR, &node->flags); |
| 456 | return node; |
| 457 | } |
| 458 | |
| 459 | void hfs_bnode_unhash(struct hfs_bnode *node) |
| 460 | { |
| 461 | struct hfs_bnode **p; |
| 462 | |
| 463 | dprint(DBG_BNODE_REFS, "remove_node(%d:%d): %d\n", |
| 464 | node->tree->cnid, node->this, atomic_read(&node->refcnt)); |
| 465 | for (p = &node->tree->node_hash[hfs_bnode_hash(node->this)]; |
| 466 | *p && *p != node; p = &(*p)->next_hash) |
| 467 | ; |
Eric Sesterhenn | 0bf3ba5 | 2006-04-01 01:14:43 +0200 | [diff] [blame] | 468 | BUG_ON(!*p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | *p = node->next_hash; |
| 470 | node->tree->node_hash_cnt--; |
| 471 | } |
| 472 | |
| 473 | /* Load a particular node out of a tree */ |
| 474 | struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num) |
| 475 | { |
| 476 | struct hfs_bnode *node; |
| 477 | struct hfs_bnode_desc *desc; |
| 478 | int i, rec_off, off, next_off; |
| 479 | int entry_size, key_size; |
| 480 | |
| 481 | spin_lock(&tree->hash_lock); |
| 482 | node = hfs_bnode_findhash(tree, num); |
| 483 | if (node) { |
| 484 | hfs_bnode_get(node); |
| 485 | spin_unlock(&tree->hash_lock); |
| 486 | wait_event(node->lock_wq, !test_bit(HFS_BNODE_NEW, &node->flags)); |
| 487 | if (test_bit(HFS_BNODE_ERROR, &node->flags)) |
| 488 | goto node_error; |
| 489 | return node; |
| 490 | } |
| 491 | spin_unlock(&tree->hash_lock); |
| 492 | node = __hfs_bnode_create(tree, num); |
| 493 | if (!node) |
| 494 | return ERR_PTR(-ENOMEM); |
| 495 | if (test_bit(HFS_BNODE_ERROR, &node->flags)) |
| 496 | goto node_error; |
| 497 | if (!test_bit(HFS_BNODE_NEW, &node->flags)) |
| 498 | return node; |
| 499 | |
| 500 | desc = (struct hfs_bnode_desc *)(kmap(node->page[0]) + node->page_offset); |
| 501 | node->prev = be32_to_cpu(desc->prev); |
| 502 | node->next = be32_to_cpu(desc->next); |
| 503 | node->num_recs = be16_to_cpu(desc->num_recs); |
| 504 | node->type = desc->type; |
| 505 | node->height = desc->height; |
| 506 | kunmap(node->page[0]); |
| 507 | |
| 508 | switch (node->type) { |
| 509 | case HFS_NODE_HEADER: |
| 510 | case HFS_NODE_MAP: |
| 511 | if (node->height != 0) |
| 512 | goto node_error; |
| 513 | break; |
| 514 | case HFS_NODE_LEAF: |
| 515 | if (node->height != 1) |
| 516 | goto node_error; |
| 517 | break; |
| 518 | case HFS_NODE_INDEX: |
| 519 | if (node->height <= 1 || node->height > tree->depth) |
| 520 | goto node_error; |
| 521 | break; |
| 522 | default: |
| 523 | goto node_error; |
| 524 | } |
| 525 | |
| 526 | rec_off = tree->node_size - 2; |
| 527 | off = hfs_bnode_read_u16(node, rec_off); |
| 528 | if (off != sizeof(struct hfs_bnode_desc)) |
| 529 | goto node_error; |
| 530 | for (i = 1; i <= node->num_recs; off = next_off, i++) { |
| 531 | rec_off -= 2; |
| 532 | next_off = hfs_bnode_read_u16(node, rec_off); |
| 533 | if (next_off <= off || |
| 534 | next_off > tree->node_size || |
| 535 | next_off & 1) |
| 536 | goto node_error; |
| 537 | entry_size = next_off - off; |
| 538 | if (node->type != HFS_NODE_INDEX && |
| 539 | node->type != HFS_NODE_LEAF) |
| 540 | continue; |
| 541 | key_size = hfs_bnode_read_u16(node, off) + 2; |
| 542 | if (key_size >= entry_size || key_size & 1) |
| 543 | goto node_error; |
| 544 | } |
| 545 | clear_bit(HFS_BNODE_NEW, &node->flags); |
| 546 | wake_up(&node->lock_wq); |
| 547 | return node; |
| 548 | |
| 549 | node_error: |
| 550 | set_bit(HFS_BNODE_ERROR, &node->flags); |
| 551 | clear_bit(HFS_BNODE_NEW, &node->flags); |
| 552 | wake_up(&node->lock_wq); |
| 553 | hfs_bnode_put(node); |
| 554 | return ERR_PTR(-EIO); |
| 555 | } |
| 556 | |
| 557 | void hfs_bnode_free(struct hfs_bnode *node) |
| 558 | { |
| 559 | //int i; |
| 560 | |
| 561 | //for (i = 0; i < node->tree->pages_per_bnode; i++) |
| 562 | // if (node->page[i]) |
| 563 | // page_cache_release(node->page[i]); |
| 564 | kfree(node); |
| 565 | } |
| 566 | |
| 567 | struct hfs_bnode *hfs_bnode_create(struct hfs_btree *tree, u32 num) |
| 568 | { |
| 569 | struct hfs_bnode *node; |
| 570 | struct page **pagep; |
| 571 | int i; |
| 572 | |
| 573 | spin_lock(&tree->hash_lock); |
| 574 | node = hfs_bnode_findhash(tree, num); |
| 575 | spin_unlock(&tree->hash_lock); |
| 576 | if (node) { |
Roman Zippel | 634725a | 2006-01-18 17:43:05 -0800 | [diff] [blame] | 577 | printk(KERN_CRIT "new node %u already hashed?\n", num); |
| 578 | WARN_ON(1); |
| 579 | return node; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | } |
| 581 | node = __hfs_bnode_create(tree, num); |
| 582 | if (!node) |
| 583 | return ERR_PTR(-ENOMEM); |
| 584 | if (test_bit(HFS_BNODE_ERROR, &node->flags)) { |
| 585 | hfs_bnode_put(node); |
| 586 | return ERR_PTR(-EIO); |
| 587 | } |
| 588 | |
| 589 | pagep = node->page; |
| 590 | memset(kmap(*pagep) + node->page_offset, 0, |
| 591 | min((int)PAGE_CACHE_SIZE, (int)tree->node_size)); |
| 592 | set_page_dirty(*pagep); |
| 593 | kunmap(*pagep); |
| 594 | for (i = 1; i < tree->pages_per_bnode; i++) { |
| 595 | memset(kmap(*++pagep), 0, PAGE_CACHE_SIZE); |
| 596 | set_page_dirty(*pagep); |
| 597 | kunmap(*pagep); |
| 598 | } |
| 599 | clear_bit(HFS_BNODE_NEW, &node->flags); |
| 600 | wake_up(&node->lock_wq); |
| 601 | |
| 602 | return node; |
| 603 | } |
| 604 | |
| 605 | void hfs_bnode_get(struct hfs_bnode *node) |
| 606 | { |
| 607 | if (node) { |
| 608 | atomic_inc(&node->refcnt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | dprint(DBG_BNODE_REFS, "get_node(%d:%d): %d\n", |
| 610 | node->tree->cnid, node->this, atomic_read(&node->refcnt)); |
| 611 | } |
| 612 | } |
| 613 | |
| 614 | /* Dispose of resources used by a node */ |
| 615 | void hfs_bnode_put(struct hfs_bnode *node) |
| 616 | { |
| 617 | if (node) { |
| 618 | struct hfs_btree *tree = node->tree; |
| 619 | int i; |
| 620 | |
| 621 | dprint(DBG_BNODE_REFS, "put_node(%d:%d): %d\n", |
| 622 | node->tree->cnid, node->this, atomic_read(&node->refcnt)); |
Eric Sesterhenn | 0bf3ba5 | 2006-04-01 01:14:43 +0200 | [diff] [blame] | 623 | BUG_ON(!atomic_read(&node->refcnt)); |
Roman Zippel | a5e3985 | 2005-09-06 15:18:47 -0700 | [diff] [blame] | 624 | if (!atomic_dec_and_lock(&node->refcnt, &tree->hash_lock)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | for (i = 0; i < tree->pages_per_bnode; i++) { |
Roman Zippel | 74f9c9c | 2005-08-01 21:11:41 -0700 | [diff] [blame] | 627 | if (!node->page[i]) |
| 628 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | mark_page_accessed(node->page[i]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 630 | } |
| 631 | |
| 632 | if (test_bit(HFS_BNODE_DELETED, &node->flags)) { |
| 633 | hfs_bnode_unhash(node); |
| 634 | spin_unlock(&tree->hash_lock); |
| 635 | hfs_bmap_free(node); |
| 636 | hfs_bnode_free(node); |
| 637 | return; |
| 638 | } |
| 639 | spin_unlock(&tree->hash_lock); |
| 640 | } |
| 641 | } |
| 642 | |