1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/hfsplus/extents.c
6 * Brad Boyer (flar@allandria.com)
7 * (C) 2003 Ardis Technologies <roman@ardistech.com>
9 * Handling of Extents both in catalog and extents overflow trees
12 #include <linux/errno.h>
14 #include <linux/pagemap.h>
16 #include "hfsplus_fs.h"
17 #include "hfsplus_raw.h"
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)
29 return be32_to_cpu(k1id) < be32_to_cpu(k2id) ? -1 : 1;
31 if (k1->ext.fork_type != k2->ext.fork_type)
32 return k1->ext.fork_type < k2->ext.fork_type ? -1 : 1;
34 k1s = k1->ext.start_block;
35 k2s = k2->ext.start_block;
38 return be32_to_cpu(k1s) < be32_to_cpu(k2s) ? -1 : 1;
41 static void hfsplus_ext_build_key(hfsplus_btree_key *key, u32 cnid,
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;
51 static u32 hfsplus_ext_find_block(struct hfsplus_extent *ext, u32 off)
56 for (i = 0; i < 8; ext++, i++) {
57 count = be32_to_cpu(ext->block_count);
59 return be32_to_cpu(ext->start_block) + off;
66 static int hfsplus_ext_block_count(struct hfsplus_extent *ext)
71 for (i = 0; i < 8; ext++, i++)
72 count += be32_to_cpu(ext->block_count);
76 static u32 hfsplus_ext_lastblock(struct hfsplus_extent *ext)
81 for (i = 0; i < 7; ext--, i++)
84 return be32_to_cpu(ext->start_block) + be32_to_cpu(ext->block_count);
87 static int __hfsplus_ext_write_extent(struct inode *inode,
88 struct hfs_find_data *fd)
90 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
93 WARN_ON(!mutex_is_locked(&hip->extents_lock));
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);
99 res = hfs_brec_find(fd, hfs_find_rec_by_key);
100 if (hip->extent_state & HFSPLUS_EXT_NEW) {
103 /* Fail early and avoid ENOSPC during the btree operation */
104 res = hfs_bmap_reserve(fd->tree, fd->tree->depth + 1);
107 hfs_brec_insert(fd, hip->cached_extents,
108 sizeof(hfsplus_extent_rec));
109 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
113 hfs_bnode_write(fd->bnode, hip->cached_extents,
114 fd->entryoffset, fd->entrylength);
115 hip->extent_state &= ~HFSPLUS_EXT_DIRTY;
119 * We can't just use hfsplus_mark_inode_dirty here, because we
120 * also get called from hfsplus_write_inode, which should not
121 * redirty the inode. Instead the callers have to be careful
122 * to explicily mark the inode dirty, too.
124 set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags);
129 static int hfsplus_ext_write_extent_locked(struct inode *inode)
133 if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) {
134 struct hfs_find_data fd;
136 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
139 res = __hfsplus_ext_write_extent(inode, &fd);
145 int hfsplus_ext_write_extent(struct inode *inode)
149 mutex_lock(&HFSPLUS_I(inode)->extents_lock);
150 res = hfsplus_ext_write_extent_locked(inode);
151 mutex_unlock(&HFSPLUS_I(inode)->extents_lock);
156 static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd,
157 struct hfsplus_extent *extent,
158 u32 cnid, u32 block, u8 type)
162 hfsplus_ext_build_key(fd->search_key, cnid, block, type);
163 fd->key->ext.cnid = 0;
164 res = hfs_brec_find(fd, hfs_find_rec_by_key);
165 if (res && res != -ENOENT)
167 if (fd->key->ext.cnid != fd->search_key->ext.cnid ||
168 fd->key->ext.fork_type != fd->search_key->ext.fork_type)
170 if (fd->entrylength != sizeof(hfsplus_extent_rec))
172 hfs_bnode_read(fd->bnode, extent, fd->entryoffset,
173 sizeof(hfsplus_extent_rec));
177 static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd,
178 struct inode *inode, u32 block)
180 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
183 WARN_ON(!mutex_is_locked(&hip->extents_lock));
185 if (hip->extent_state & HFSPLUS_EXT_DIRTY) {
186 res = __hfsplus_ext_write_extent(inode, fd);
191 res = __hfsplus_ext_read_extent(fd, hip->cached_extents, inode->i_ino,
192 block, HFSPLUS_IS_RSRC(inode) ?
196 hip->cached_start = be32_to_cpu(fd->key->ext.start_block);
198 hfsplus_ext_block_count(hip->cached_extents);
200 hip->cached_start = hip->cached_blocks = 0;
201 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
206 static int hfsplus_ext_read_extent(struct inode *inode, u32 block)
208 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
209 struct hfs_find_data fd;
212 if (block >= hip->cached_start &&
213 block < hip->cached_start + hip->cached_blocks)
216 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
218 res = __hfsplus_ext_cache_extent(&fd, inode, block);
224 /* Get a block at iblock for inode, possibly allocating if create */
225 int hfsplus_get_block(struct inode *inode, sector_t iblock,
226 struct buffer_head *bh_result, int create)
228 struct super_block *sb = inode->i_sb;
229 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
230 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
232 u32 ablock, dblock, mask;
236 /* Convert inode block to disk allocation block */
237 ablock = iblock >> sbi->fs_shift;
239 if (iblock >= hip->fs_blocks) {
242 if (iblock > hip->fs_blocks)
244 if (ablock >= hip->alloc_blocks) {
245 res = hfsplus_file_extend(inode, false);
252 if (ablock < hip->first_blocks) {
253 dblock = hfsplus_ext_find_block(hip->first_extents, ablock);
257 if (inode->i_ino == HFSPLUS_EXT_CNID)
260 mutex_lock(&hip->extents_lock);
263 * hfsplus_ext_read_extent will write out a cached extent into
264 * the extents btree. In that case we may have to mark the inode
265 * dirty even for a pure read of an extent here.
267 was_dirty = (hip->extent_state & HFSPLUS_EXT_DIRTY);
268 res = hfsplus_ext_read_extent(inode, ablock);
270 mutex_unlock(&hip->extents_lock);
273 dblock = hfsplus_ext_find_block(hip->cached_extents,
274 ablock - hip->cached_start);
275 mutex_unlock(&hip->extents_lock);
278 hfs_dbg(EXTENT, "get_block(%lu): %llu - %u\n",
279 inode->i_ino, (long long)iblock, dblock);
281 mask = (1 << sbi->fs_shift) - 1;
282 sector = ((sector_t)dblock << sbi->fs_shift) +
283 sbi->blockoffset + (iblock & mask);
284 map_bh(bh_result, sb, sector);
287 set_buffer_new(bh_result);
288 hip->phys_size += sb->s_blocksize;
290 inode_add_bytes(inode, sb->s_blocksize);
292 if (create || was_dirty)
293 mark_inode_dirty(inode);
297 static void hfsplus_dump_extent(struct hfsplus_extent *extent)
301 hfs_dbg(EXTENT, " ");
302 for (i = 0; i < 8; i++)
303 hfs_dbg_cont(EXTENT, " %u:%u",
304 be32_to_cpu(extent[i].start_block),
305 be32_to_cpu(extent[i].block_count));
306 hfs_dbg_cont(EXTENT, "\n");
309 static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset,
310 u32 alloc_block, u32 block_count)
315 hfsplus_dump_extent(extent);
316 for (i = 0; i < 8; extent++, i++) {
317 count = be32_to_cpu(extent->block_count);
318 if (offset == count) {
319 start = be32_to_cpu(extent->start_block);
320 if (alloc_block != start + count) {
324 extent->start_block = cpu_to_be32(alloc_block);
326 block_count += count;
327 extent->block_count = cpu_to_be32(block_count);
329 } else if (offset < count)
337 static int hfsplus_free_extents(struct super_block *sb,
338 struct hfsplus_extent *extent,
339 u32 offset, u32 block_nr)
345 /* Mapping the allocation file may lock the extent tree */
346 WARN_ON(mutex_is_locked(&HFSPLUS_SB(sb)->ext_tree->tree_lock));
348 hfsplus_dump_extent(extent);
349 for (i = 0; i < 8; extent++, i++) {
350 count = be32_to_cpu(extent->block_count);
353 else if (offset < count)
361 start = be32_to_cpu(extent->start_block);
362 if (count <= block_nr) {
363 err = hfsplus_block_free(sb, start, count);
365 pr_err("can't free extent\n");
366 hfs_dbg(EXTENT, " start: %u count: %u\n",
369 extent->block_count = 0;
370 extent->start_block = 0;
374 err = hfsplus_block_free(sb, start + count, block_nr);
376 pr_err("can't free extent\n");
377 hfs_dbg(EXTENT, " start: %u count: %u\n",
380 extent->block_count = cpu_to_be32(count);
383 if (!block_nr || !i) {
385 * Try to free all extents and
386 * return only last error
392 count = be32_to_cpu(extent->block_count);
396 int hfsplus_free_fork(struct super_block *sb, u32 cnid,
397 struct hfsplus_fork_raw *fork, int type)
399 struct hfs_find_data fd;
400 hfsplus_extent_rec ext_entry;
401 u32 total_blocks, blocks, start;
404 total_blocks = be32_to_cpu(fork->total_blocks);
409 for (i = 0; i < 8; i++)
410 blocks += be32_to_cpu(fork->extents[i].block_count);
412 res = hfsplus_free_extents(sb, fork->extents, blocks, blocks);
415 if (total_blocks == blocks)
418 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
422 res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid,
426 start = be32_to_cpu(fd.key->ext.start_block);
427 hfs_brec_remove(&fd);
429 mutex_unlock(&fd.tree->tree_lock);
430 hfsplus_free_extents(sb, ext_entry, total_blocks - start,
432 total_blocks = start;
433 mutex_lock(&fd.tree->tree_lock);
434 } while (total_blocks > blocks);
440 int hfsplus_file_extend(struct inode *inode, bool zeroout)
442 struct super_block *sb = inode->i_sb;
443 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
444 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
445 u32 start, len, goal;
448 if (sbi->alloc_file->i_size * 8 <
449 sbi->total_blocks - sbi->free_blocks + 8) {
450 /* extend alloc file */
451 pr_err("extend alloc file! (%llu,%u,%u)\n",
452 sbi->alloc_file->i_size * 8,
453 sbi->total_blocks, sbi->free_blocks);
457 mutex_lock(&hip->extents_lock);
458 if (hip->alloc_blocks == hip->first_blocks)
459 goal = hfsplus_ext_lastblock(hip->first_extents);
461 res = hfsplus_ext_read_extent(inode, hip->alloc_blocks);
464 goal = hfsplus_ext_lastblock(hip->cached_extents);
467 len = hip->clump_blocks;
468 start = hfsplus_block_allocate(sb, sbi->total_blocks, goal, &len);
469 if (start >= sbi->total_blocks) {
470 start = hfsplus_block_allocate(sb, goal, 0, &len);
478 res = sb_issue_zeroout(sb, start, len, GFP_NOFS);
483 hfs_dbg(EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len);
485 if (hip->alloc_blocks <= hip->first_blocks) {
486 if (!hip->first_blocks) {
487 hfs_dbg(EXTENT, "first extents\n");
489 hip->first_extents[0].start_block = cpu_to_be32(start);
490 hip->first_extents[0].block_count = cpu_to_be32(len);
493 /* try to append to extents in inode */
494 res = hfsplus_add_extent(hip->first_extents,
501 hfsplus_dump_extent(hip->first_extents);
502 hip->first_blocks += len;
505 res = hfsplus_add_extent(hip->cached_extents,
506 hip->alloc_blocks - hip->cached_start,
509 hfsplus_dump_extent(hip->cached_extents);
510 hip->extent_state |= HFSPLUS_EXT_DIRTY;
511 hip->cached_blocks += len;
512 } else if (res == -ENOSPC)
517 hip->alloc_blocks += len;
518 mutex_unlock(&hip->extents_lock);
519 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);
522 mutex_unlock(&hip->extents_lock);
526 hfs_dbg(EXTENT, "insert new extent\n");
527 res = hfsplus_ext_write_extent_locked(inode);
531 memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
532 hip->cached_extents[0].start_block = cpu_to_be32(start);
533 hip->cached_extents[0].block_count = cpu_to_be32(len);
534 hfsplus_dump_extent(hip->cached_extents);
535 hip->extent_state |= HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW;
536 hip->cached_start = hip->alloc_blocks;
537 hip->cached_blocks = len;
543 void hfsplus_file_truncate(struct inode *inode)
545 struct super_block *sb = inode->i_sb;
546 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
547 struct hfs_find_data fd;
548 u32 alloc_cnt, blk_cnt, start;
551 hfs_dbg(INODE, "truncate: %lu, %llu -> %llu\n",
552 inode->i_ino, (long long)hip->phys_size, inode->i_size);
554 if (inode->i_size > hip->phys_size) {
555 struct address_space *mapping = inode->i_mapping;
558 loff_t size = inode->i_size;
560 res = pagecache_write_begin(NULL, mapping, size, 0, 0,
564 res = pagecache_write_end(NULL, mapping, size,
568 mark_inode_dirty(inode);
570 } else if (inode->i_size == hip->phys_size)
573 blk_cnt = (inode->i_size + HFSPLUS_SB(sb)->alloc_blksz - 1) >>
574 HFSPLUS_SB(sb)->alloc_blksz_shift;
576 mutex_lock(&hip->extents_lock);
578 alloc_cnt = hip->alloc_blocks;
579 if (blk_cnt == alloc_cnt)
582 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
584 mutex_unlock(&hip->extents_lock);
585 /* XXX: We lack error handling of hfsplus_file_truncate() */
589 if (alloc_cnt == hip->first_blocks) {
590 mutex_unlock(&fd.tree->tree_lock);
591 hfsplus_free_extents(sb, hip->first_extents,
592 alloc_cnt, alloc_cnt - blk_cnt);
593 hfsplus_dump_extent(hip->first_extents);
594 hip->first_blocks = blk_cnt;
595 mutex_lock(&fd.tree->tree_lock);
598 res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt);
601 hfs_brec_remove(&fd);
603 mutex_unlock(&fd.tree->tree_lock);
604 start = hip->cached_start;
605 hfsplus_free_extents(sb, hip->cached_extents,
606 alloc_cnt - start, alloc_cnt - blk_cnt);
607 hfsplus_dump_extent(hip->cached_extents);
608 if (blk_cnt > start) {
609 hip->extent_state |= HFSPLUS_EXT_DIRTY;
613 hip->cached_start = hip->cached_blocks = 0;
614 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
615 mutex_lock(&fd.tree->tree_lock);
619 hip->alloc_blocks = blk_cnt;
621 mutex_unlock(&hip->extents_lock);
622 hip->phys_size = inode->i_size;
623 hip->fs_blocks = (inode->i_size + sb->s_blocksize - 1) >>
624 sb->s_blocksize_bits;
625 inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits);
626 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);