1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/hfsplus/extents.c 4 * 5 * Copyright (C) 2001 6 * Brad Boyer (flar@allandria.com) 7 * (C) 2003 Ardis Technologies <roman@ardistech.com> 8 * 9 * Handling of Extents both in catalog and extents overflow trees 10 */ 11 12 #include <linux/errno.h> 13 #include <linux/fs.h> 14 #include <linux/pagemap.h> 15 16 #include "hfsplus_fs.h" 17 #include "hfsplus_raw.h" 18 19 /* Compare two extents keys, returns 0 on same, pos/neg for difference */ 20 int hfsplus_ext_cmp_key(const hfsplus_btree_key *k1, 21 const hfsplus_btree_key *k2) 22 { 23 __be32 k1id, k2id; 24 __be32 k1s, k2s; 25 26 k1id = k1->ext.cnid; 27 k2id = k2->ext.cnid; 28 if (k1id != k2id) 29 return be32_to_cpu(k1id) < be32_to_cpu(k2id) ? -1 : 1; 30 31 if (k1->ext.fork_type != k2->ext.fork_type) 32 return k1->ext.fork_type < k2->ext.fork_type ? -1 : 1; 33 34 k1s = k1->ext.start_block; 35 k2s = k2->ext.start_block; 36 if (k1s == k2s) 37 return 0; 38 return be32_to_cpu(k1s) < be32_to_cpu(k2s) ? -1 : 1; 39 } 40 41 static void hfsplus_ext_build_key(hfsplus_btree_key *key, u32 cnid, 42 u32 block, u8 type) 43 { 44 key->key_len = cpu_to_be16(HFSPLUS_EXT_KEYLEN - 2); 45 key->ext.cnid = cpu_to_be32(cnid); 46 key->ext.start_block = cpu_to_be32(block); 47 key->ext.fork_type = type; 48 key->ext.pad = 0; 49 } 50 51 static u32 hfsplus_ext_find_block(struct hfsplus_extent *ext, u32 off) 52 { 53 int i; 54 u32 count; 55 56 for (i = 0; i < 8; ext++, i++) { 57 count = be32_to_cpu(ext->block_count); 58 if (off < count) 59 return be32_to_cpu(ext->start_block) + off; 60 off -= count; 61 } 62 /* panic? */ 63 return 0; 64 } 65 66 static int hfsplus_ext_block_count(struct hfsplus_extent *ext) 67 { 68 int i; 69 u32 count = 0; 70 71 for (i = 0; i < 8; ext++, i++) 72 count += be32_to_cpu(ext->block_count); 73 return count; 74 } 75 76 static u32 hfsplus_ext_lastblock(struct hfsplus_extent *ext) 77 { 78 int i; 79 80 ext += 7; 81 for (i = 0; i < 7; ext--, i++) 82 if (ext->block_count) 83 break; 84 return be32_to_cpu(ext->start_block) + be32_to_cpu(ext->block_count); 85 } 86 87 static int __hfsplus_ext_write_extent(struct inode *inode, 88 struct hfs_find_data *fd) 89 { 90 struct hfsplus_inode_info *hip = HFSPLUS_I(inode); 91 int res; 92 93 WARN_ON(!mutex_is_locked(&hip->extents_lock)); 94 95 hfsplus_ext_build_key(fd->search_key, inode->i_ino, hip->cached_start, 96 HFSPLUS_IS_RSRC(inode) ? 97 HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA); 98 99 res = hfs_brec_find(fd, hfs_find_rec_by_key); 100 if (hip->extent_state & HFSPLUS_EXT_NEW) { 101 if (res != -ENOENT) 102 return res; 103 hfs_brec_insert(fd, hip->cached_extents, 104 sizeof(hfsplus_extent_rec)); 105 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); 106 } else { 107 if (res) 108 return res; 109 hfs_bnode_write(fd->bnode, hip->cached_extents, 110 fd->entryoffset, fd->entrylength); 111 hip->extent_state &= ~HFSPLUS_EXT_DIRTY; 112 } 113 114 /* 115 * We can't just use hfsplus_mark_inode_dirty here, because we 116 * also get called from hfsplus_write_inode, which should not 117 * redirty the inode. Instead the callers have to be careful 118 * to explicily mark the inode dirty, too. 119 */ 120 set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags); 121 122 return 0; 123 } 124 125 static int hfsplus_ext_write_extent_locked(struct inode *inode) 126 { 127 int res = 0; 128 129 if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) { 130 struct hfs_find_data fd; 131 132 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd); 133 if (res) 134 return res; 135 res = __hfsplus_ext_write_extent(inode, &fd); 136 hfs_find_exit(&fd); 137 } 138 return res; 139 } 140 141 int hfsplus_ext_write_extent(struct inode *inode) 142 { 143 int res; 144 145 mutex_lock(&HFSPLUS_I(inode)->extents_lock); 146 res = hfsplus_ext_write_extent_locked(inode); 147 mutex_unlock(&HFSPLUS_I(inode)->extents_lock); 148 149 return res; 150 } 151 152 static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd, 153 struct hfsplus_extent *extent, 154 u32 cnid, u32 block, u8 type) 155 { 156 int res; 157 158 hfsplus_ext_build_key(fd->search_key, cnid, block, type); 159 fd->key->ext.cnid = 0; 160 res = hfs_brec_find(fd, hfs_find_rec_by_key); 161 if (res && res != -ENOENT) 162 return res; 163 if (fd->key->ext.cnid != fd->search_key->ext.cnid || 164 fd->key->ext.fork_type != fd->search_key->ext.fork_type) 165 return -ENOENT; 166 if (fd->entrylength != sizeof(hfsplus_extent_rec)) 167 return -EIO; 168 hfs_bnode_read(fd->bnode, extent, fd->entryoffset, 169 sizeof(hfsplus_extent_rec)); 170 return 0; 171 } 172 173 static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd, 174 struct inode *inode, u32 block) 175 { 176 struct hfsplus_inode_info *hip = HFSPLUS_I(inode); 177 int res; 178 179 WARN_ON(!mutex_is_locked(&hip->extents_lock)); 180 181 if (hip->extent_state & HFSPLUS_EXT_DIRTY) { 182 res = __hfsplus_ext_write_extent(inode, fd); 183 if (res) 184 return res; 185 } 186 187 res = __hfsplus_ext_read_extent(fd, hip->cached_extents, inode->i_ino, 188 block, HFSPLUS_IS_RSRC(inode) ? 189 HFSPLUS_TYPE_RSRC : 190 HFSPLUS_TYPE_DATA); 191 if (!res) { 192 hip->cached_start = be32_to_cpu(fd->key->ext.start_block); 193 hip->cached_blocks = 194 hfsplus_ext_block_count(hip->cached_extents); 195 } else { 196 hip->cached_start = hip->cached_blocks = 0; 197 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); 198 } 199 return res; 200 } 201 202 static int hfsplus_ext_read_extent(struct inode *inode, u32 block) 203 { 204 struct hfsplus_inode_info *hip = HFSPLUS_I(inode); 205 struct hfs_find_data fd; 206 int res; 207 208 if (block >= hip->cached_start && 209 block < hip->cached_start + hip->cached_blocks) 210 return 0; 211 212 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd); 213 if (!res) { 214 res = __hfsplus_ext_cache_extent(&fd, inode, block); 215 hfs_find_exit(&fd); 216 } 217 return res; 218 } 219 220 /* Get a block at iblock for inode, possibly allocating if create */ 221 int hfsplus_get_block(struct inode *inode, sector_t iblock, 222 struct buffer_head *bh_result, int create) 223 { 224 struct super_block *sb = inode->i_sb; 225 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb); 226 struct hfsplus_inode_info *hip = HFSPLUS_I(inode); 227 int res = -EIO; 228 u32 ablock, dblock, mask; 229 sector_t sector; 230 int was_dirty = 0; 231 232 /* Convert inode block to disk allocation block */ 233 ablock = iblock >> sbi->fs_shift; 234 235 if (iblock >= hip->fs_blocks) { 236 if (iblock > hip->fs_blocks || !create) 237 return -EIO; 238 if (ablock >= hip->alloc_blocks) { 239 res = hfsplus_file_extend(inode, false); 240 if (res) 241 return res; 242 } 243 } else 244 create = 0; 245 246 if (ablock < hip->first_blocks) { 247 dblock = hfsplus_ext_find_block(hip->first_extents, ablock); 248 goto done; 249 } 250 251 if (inode->i_ino == HFSPLUS_EXT_CNID) 252 return -EIO; 253 254 mutex_lock(&hip->extents_lock); 255 256 /* 257 * hfsplus_ext_read_extent will write out a cached extent into 258 * the extents btree. In that case we may have to mark the inode 259 * dirty even for a pure read of an extent here. 260 */ 261 was_dirty = (hip->extent_state & HFSPLUS_EXT_DIRTY); 262 res = hfsplus_ext_read_extent(inode, ablock); 263 if (res) { 264 mutex_unlock(&hip->extents_lock); 265 return -EIO; 266 } 267 dblock = hfsplus_ext_find_block(hip->cached_extents, 268 ablock - hip->cached_start); 269 mutex_unlock(&hip->extents_lock); 270 271 done: 272 hfs_dbg(EXTENT, "get_block(%lu): %llu - %u\n", 273 inode->i_ino, (long long)iblock, dblock); 274 275 mask = (1 << sbi->fs_shift) - 1; 276 sector = ((sector_t)dblock << sbi->fs_shift) + 277 sbi->blockoffset + (iblock & mask); 278 map_bh(bh_result, sb, sector); 279 280 if (create) { 281 set_buffer_new(bh_result); 282 hip->phys_size += sb->s_blocksize; 283 hip->fs_blocks++; 284 inode_add_bytes(inode, sb->s_blocksize); 285 } 286 if (create || was_dirty) 287 mark_inode_dirty(inode); 288 return 0; 289 } 290 291 static void hfsplus_dump_extent(struct hfsplus_extent *extent) 292 { 293 int i; 294 295 hfs_dbg(EXTENT, " "); 296 for (i = 0; i < 8; i++) 297 hfs_dbg_cont(EXTENT, " %u:%u", 298 be32_to_cpu(extent[i].start_block), 299 be32_to_cpu(extent[i].block_count)); 300 hfs_dbg_cont(EXTENT, "\n"); 301 } 302 303 static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset, 304 u32 alloc_block, u32 block_count) 305 { 306 u32 count, start; 307 int i; 308 309 hfsplus_dump_extent(extent); 310 for (i = 0; i < 8; extent++, i++) { 311 count = be32_to_cpu(extent->block_count); 312 if (offset == count) { 313 start = be32_to_cpu(extent->start_block); 314 if (alloc_block != start + count) { 315 if (++i >= 8) 316 return -ENOSPC; 317 extent++; 318 extent->start_block = cpu_to_be32(alloc_block); 319 } else 320 block_count += count; 321 extent->block_count = cpu_to_be32(block_count); 322 return 0; 323 } else if (offset < count) 324 break; 325 offset -= count; 326 } 327 /* panic? */ 328 return -EIO; 329 } 330 331 static int hfsplus_free_extents(struct super_block *sb, 332 struct hfsplus_extent *extent, 333 u32 offset, u32 block_nr) 334 { 335 u32 count, start; 336 int i; 337 int err = 0; 338 339 hfsplus_dump_extent(extent); 340 for (i = 0; i < 8; extent++, i++) { 341 count = be32_to_cpu(extent->block_count); 342 if (offset == count) 343 goto found; 344 else if (offset < count) 345 break; 346 offset -= count; 347 } 348 /* panic? */ 349 return -EIO; 350 found: 351 for (;;) { 352 start = be32_to_cpu(extent->start_block); 353 if (count <= block_nr) { 354 err = hfsplus_block_free(sb, start, count); 355 if (err) { 356 pr_err("can't free extent\n"); 357 hfs_dbg(EXTENT, " start: %u count: %u\n", 358 start, count); 359 } 360 extent->block_count = 0; 361 extent->start_block = 0; 362 block_nr -= count; 363 } else { 364 count -= block_nr; 365 err = hfsplus_block_free(sb, start + count, block_nr); 366 if (err) { 367 pr_err("can't free extent\n"); 368 hfs_dbg(EXTENT, " start: %u count: %u\n", 369 start, count); 370 } 371 extent->block_count = cpu_to_be32(count); 372 block_nr = 0; 373 } 374 if (!block_nr || !i) { 375 /* 376 * Try to free all extents and 377 * return only last error 378 */ 379 return err; 380 } 381 i--; 382 extent--; 383 count = be32_to_cpu(extent->block_count); 384 } 385 } 386 387 int hfsplus_free_fork(struct super_block *sb, u32 cnid, 388 struct hfsplus_fork_raw *fork, int type) 389 { 390 struct hfs_find_data fd; 391 hfsplus_extent_rec ext_entry; 392 u32 total_blocks, blocks, start; 393 int res, i; 394 395 total_blocks = be32_to_cpu(fork->total_blocks); 396 if (!total_blocks) 397 return 0; 398 399 blocks = 0; 400 for (i = 0; i < 8; i++) 401 blocks += be32_to_cpu(fork->extents[i].block_count); 402 403 res = hfsplus_free_extents(sb, fork->extents, blocks, blocks); 404 if (res) 405 return res; 406 if (total_blocks == blocks) 407 return 0; 408 409 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd); 410 if (res) 411 return res; 412 do { 413 res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid, 414 total_blocks, type); 415 if (res) 416 break; 417 start = be32_to_cpu(fd.key->ext.start_block); 418 hfsplus_free_extents(sb, ext_entry, 419 total_blocks - start, 420 total_blocks); 421 hfs_brec_remove(&fd); 422 total_blocks = start; 423 } while (total_blocks > blocks); 424 hfs_find_exit(&fd); 425 426 return res; 427 } 428 429 int hfsplus_file_extend(struct inode *inode, bool zeroout) 430 { 431 struct super_block *sb = inode->i_sb; 432 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb); 433 struct hfsplus_inode_info *hip = HFSPLUS_I(inode); 434 u32 start, len, goal; 435 int res; 436 437 if (sbi->alloc_file->i_size * 8 < 438 sbi->total_blocks - sbi->free_blocks + 8) { 439 /* extend alloc file */ 440 pr_err("extend alloc file! (%llu,%u,%u)\n", 441 sbi->alloc_file->i_size * 8, 442 sbi->total_blocks, sbi->free_blocks); 443 return -ENOSPC; 444 } 445 446 mutex_lock(&hip->extents_lock); 447 if (hip->alloc_blocks == hip->first_blocks) 448 goal = hfsplus_ext_lastblock(hip->first_extents); 449 else { 450 res = hfsplus_ext_read_extent(inode, hip->alloc_blocks); 451 if (res) 452 goto out; 453 goal = hfsplus_ext_lastblock(hip->cached_extents); 454 } 455 456 len = hip->clump_blocks; 457 start = hfsplus_block_allocate(sb, sbi->total_blocks, goal, &len); 458 if (start >= sbi->total_blocks) { 459 start = hfsplus_block_allocate(sb, goal, 0, &len); 460 if (start >= goal) { 461 res = -ENOSPC; 462 goto out; 463 } 464 } 465 466 if (zeroout) { 467 res = sb_issue_zeroout(sb, start, len, GFP_NOFS); 468 if (res) 469 goto out; 470 } 471 472 hfs_dbg(EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len); 473 474 if (hip->alloc_blocks <= hip->first_blocks) { 475 if (!hip->first_blocks) { 476 hfs_dbg(EXTENT, "first extents\n"); 477 /* no extents yet */ 478 hip->first_extents[0].start_block = cpu_to_be32(start); 479 hip->first_extents[0].block_count = cpu_to_be32(len); 480 res = 0; 481 } else { 482 /* try to append to extents in inode */ 483 res = hfsplus_add_extent(hip->first_extents, 484 hip->alloc_blocks, 485 start, len); 486 if (res == -ENOSPC) 487 goto insert_extent; 488 } 489 if (!res) { 490 hfsplus_dump_extent(hip->first_extents); 491 hip->first_blocks += len; 492 } 493 } else { 494 res = hfsplus_add_extent(hip->cached_extents, 495 hip->alloc_blocks - hip->cached_start, 496 start, len); 497 if (!res) { 498 hfsplus_dump_extent(hip->cached_extents); 499 hip->extent_state |= HFSPLUS_EXT_DIRTY; 500 hip->cached_blocks += len; 501 } else if (res == -ENOSPC) 502 goto insert_extent; 503 } 504 out: 505 if (!res) { 506 hip->alloc_blocks += len; 507 mutex_unlock(&hip->extents_lock); 508 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY); 509 return 0; 510 } 511 mutex_unlock(&hip->extents_lock); 512 return res; 513 514 insert_extent: 515 hfs_dbg(EXTENT, "insert new extent\n"); 516 res = hfsplus_ext_write_extent_locked(inode); 517 if (res) 518 goto out; 519 520 memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec)); 521 hip->cached_extents[0].start_block = cpu_to_be32(start); 522 hip->cached_extents[0].block_count = cpu_to_be32(len); 523 hfsplus_dump_extent(hip->cached_extents); 524 hip->extent_state |= HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW; 525 hip->cached_start = hip->alloc_blocks; 526 hip->cached_blocks = len; 527 528 res = 0; 529 goto out; 530 } 531 532 void hfsplus_file_truncate(struct inode *inode) 533 { 534 struct super_block *sb = inode->i_sb; 535 struct hfsplus_inode_info *hip = HFSPLUS_I(inode); 536 struct hfs_find_data fd; 537 u32 alloc_cnt, blk_cnt, start; 538 int res; 539 540 hfs_dbg(INODE, "truncate: %lu, %llu -> %llu\n", 541 inode->i_ino, (long long)hip->phys_size, inode->i_size); 542 543 if (inode->i_size > hip->phys_size) { 544 struct address_space *mapping = inode->i_mapping; 545 struct page *page; 546 void *fsdata; 547 loff_t size = inode->i_size; 548 549 res = pagecache_write_begin(NULL, mapping, size, 0, 0, 550 &page, &fsdata); 551 if (res) 552 return; 553 res = pagecache_write_end(NULL, mapping, size, 554 0, 0, page, fsdata); 555 if (res < 0) 556 return; 557 mark_inode_dirty(inode); 558 return; 559 } else if (inode->i_size == hip->phys_size) 560 return; 561 562 blk_cnt = (inode->i_size + HFSPLUS_SB(sb)->alloc_blksz - 1) >> 563 HFSPLUS_SB(sb)->alloc_blksz_shift; 564 565 mutex_lock(&hip->extents_lock); 566 567 alloc_cnt = hip->alloc_blocks; 568 if (blk_cnt == alloc_cnt) 569 goto out_unlock; 570 571 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd); 572 if (res) { 573 mutex_unlock(&hip->extents_lock); 574 /* XXX: We lack error handling of hfsplus_file_truncate() */ 575 return; 576 } 577 while (1) { 578 if (alloc_cnt == hip->first_blocks) { 579 hfsplus_free_extents(sb, hip->first_extents, 580 alloc_cnt, alloc_cnt - blk_cnt); 581 hfsplus_dump_extent(hip->first_extents); 582 hip->first_blocks = blk_cnt; 583 break; 584 } 585 res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt); 586 if (res) 587 break; 588 start = hip->cached_start; 589 hfsplus_free_extents(sb, hip->cached_extents, 590 alloc_cnt - start, alloc_cnt - blk_cnt); 591 hfsplus_dump_extent(hip->cached_extents); 592 if (blk_cnt > start) { 593 hip->extent_state |= HFSPLUS_EXT_DIRTY; 594 break; 595 } 596 alloc_cnt = start; 597 hip->cached_start = hip->cached_blocks = 0; 598 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); 599 hfs_brec_remove(&fd); 600 } 601 hfs_find_exit(&fd); 602 603 hip->alloc_blocks = blk_cnt; 604 out_unlock: 605 mutex_unlock(&hip->extents_lock); 606 hip->phys_size = inode->i_size; 607 hip->fs_blocks = (inode->i_size + sb->s_blocksize - 1) >> 608 sb->s_blocksize_bits; 609 inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits); 610 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY); 611 } 612