2 * linux/fs/hfsplus/extents.c
5 * Brad Boyer (flar@allandria.com)
6 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 * Handling of Extents both in catalog and extents overflow trees
11 #include <linux/errno.h>
13 #include <linux/pagemap.h>
15 #include "hfsplus_fs.h"
16 #include "hfsplus_raw.h"
18 /* Compare two extents keys, returns 0 on same, pos/neg for difference */
19 int hfsplus_ext_cmp_key(const hfsplus_btree_key *k1,
20 const hfsplus_btree_key *k2)
28 return be32_to_cpu(k1id) < be32_to_cpu(k2id) ? -1 : 1;
30 if (k1->ext.fork_type != k2->ext.fork_type)
31 return k1->ext.fork_type < k2->ext.fork_type ? -1 : 1;
33 k1s = k1->ext.start_block;
34 k2s = k2->ext.start_block;
37 return be32_to_cpu(k1s) < be32_to_cpu(k2s) ? -1 : 1;
40 static void hfsplus_ext_build_key(hfsplus_btree_key *key, u32 cnid,
43 key->key_len = cpu_to_be16(HFSPLUS_EXT_KEYLEN - 2);
44 key->ext.cnid = cpu_to_be32(cnid);
45 key->ext.start_block = cpu_to_be32(block);
46 key->ext.fork_type = type;
50 static u32 hfsplus_ext_find_block(struct hfsplus_extent *ext, u32 off)
55 for (i = 0; i < 8; ext++, i++) {
56 count = be32_to_cpu(ext->block_count);
58 return be32_to_cpu(ext->start_block) + off;
65 static int hfsplus_ext_block_count(struct hfsplus_extent *ext)
70 for (i = 0; i < 8; ext++, i++)
71 count += be32_to_cpu(ext->block_count);
75 static u32 hfsplus_ext_lastblock(struct hfsplus_extent *ext)
80 for (i = 0; i < 7; ext--, i++)
83 return be32_to_cpu(ext->start_block) + be32_to_cpu(ext->block_count);
86 static int __hfsplus_ext_write_extent(struct inode *inode,
87 struct hfs_find_data *fd)
89 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
92 WARN_ON(!mutex_is_locked(&hip->extents_lock));
94 hfsplus_ext_build_key(fd->search_key, inode->i_ino, hip->cached_start,
95 HFSPLUS_IS_RSRC(inode) ?
96 HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
98 res = hfs_brec_find(fd, hfs_find_rec_by_key);
99 if (hip->extent_state & HFSPLUS_EXT_NEW) {
102 /* Fail early and avoid ENOSPC during the btree operation */
103 res = hfs_bmap_reserve(fd->tree, fd->tree->depth + 1);
106 hfs_brec_insert(fd, hip->cached_extents,
107 sizeof(hfsplus_extent_rec));
108 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
112 hfs_bnode_write(fd->bnode, hip->cached_extents,
113 fd->entryoffset, fd->entrylength);
114 hip->extent_state &= ~HFSPLUS_EXT_DIRTY;
118 * We can't just use hfsplus_mark_inode_dirty here, because we
119 * also get called from hfsplus_write_inode, which should not
120 * redirty the inode. Instead the callers have to be careful
121 * to explicily mark the inode dirty, too.
123 set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags);
128 static int hfsplus_ext_write_extent_locked(struct inode *inode)
132 if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) {
133 struct hfs_find_data fd;
135 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
138 res = __hfsplus_ext_write_extent(inode, &fd);
144 int hfsplus_ext_write_extent(struct inode *inode)
148 mutex_lock(&HFSPLUS_I(inode)->extents_lock);
149 res = hfsplus_ext_write_extent_locked(inode);
150 mutex_unlock(&HFSPLUS_I(inode)->extents_lock);
155 static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd,
156 struct hfsplus_extent *extent,
157 u32 cnid, u32 block, u8 type)
161 hfsplus_ext_build_key(fd->search_key, cnid, block, type);
162 fd->key->ext.cnid = 0;
163 res = hfs_brec_find(fd, hfs_find_rec_by_key);
164 if (res && res != -ENOENT)
166 if (fd->key->ext.cnid != fd->search_key->ext.cnid ||
167 fd->key->ext.fork_type != fd->search_key->ext.fork_type)
169 if (fd->entrylength != sizeof(hfsplus_extent_rec))
171 hfs_bnode_read(fd->bnode, extent, fd->entryoffset,
172 sizeof(hfsplus_extent_rec));
176 static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd,
177 struct inode *inode, u32 block)
179 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
182 WARN_ON(!mutex_is_locked(&hip->extents_lock));
184 if (hip->extent_state & HFSPLUS_EXT_DIRTY) {
185 res = __hfsplus_ext_write_extent(inode, fd);
190 res = __hfsplus_ext_read_extent(fd, hip->cached_extents, inode->i_ino,
191 block, HFSPLUS_IS_RSRC(inode) ?
195 hip->cached_start = be32_to_cpu(fd->key->ext.start_block);
197 hfsplus_ext_block_count(hip->cached_extents);
199 hip->cached_start = hip->cached_blocks = 0;
200 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
205 static int hfsplus_ext_read_extent(struct inode *inode, u32 block)
207 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
208 struct hfs_find_data fd;
211 if (block >= hip->cached_start &&
212 block < hip->cached_start + hip->cached_blocks)
215 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
217 res = __hfsplus_ext_cache_extent(&fd, inode, block);
223 /* Get a block at iblock for inode, possibly allocating if create */
224 int hfsplus_get_block(struct inode *inode, sector_t iblock,
225 struct buffer_head *bh_result, int create)
227 struct super_block *sb = inode->i_sb;
228 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
229 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
231 u32 ablock, dblock, mask;
235 /* Convert inode block to disk allocation block */
236 ablock = iblock >> sbi->fs_shift;
238 if (iblock >= hip->fs_blocks) {
241 if (iblock > hip->fs_blocks)
243 if (ablock >= hip->alloc_blocks) {
244 res = hfsplus_file_extend(inode, false);
251 if (ablock < hip->first_blocks) {
252 dblock = hfsplus_ext_find_block(hip->first_extents, ablock);
256 if (inode->i_ino == HFSPLUS_EXT_CNID)
259 mutex_lock(&hip->extents_lock);
262 * hfsplus_ext_read_extent will write out a cached extent into
263 * the extents btree. In that case we may have to mark the inode
264 * dirty even for a pure read of an extent here.
266 was_dirty = (hip->extent_state & HFSPLUS_EXT_DIRTY);
267 res = hfsplus_ext_read_extent(inode, ablock);
269 mutex_unlock(&hip->extents_lock);
272 dblock = hfsplus_ext_find_block(hip->cached_extents,
273 ablock - hip->cached_start);
274 mutex_unlock(&hip->extents_lock);
277 hfs_dbg(EXTENT, "get_block(%lu): %llu - %u\n",
278 inode->i_ino, (long long)iblock, dblock);
280 mask = (1 << sbi->fs_shift) - 1;
281 sector = ((sector_t)dblock << sbi->fs_shift) +
282 sbi->blockoffset + (iblock & mask);
283 map_bh(bh_result, sb, sector);
286 set_buffer_new(bh_result);
287 hip->phys_size += sb->s_blocksize;
289 inode_add_bytes(inode, sb->s_blocksize);
291 if (create || was_dirty)
292 mark_inode_dirty(inode);
296 static void hfsplus_dump_extent(struct hfsplus_extent *extent)
300 hfs_dbg(EXTENT, " ");
301 for (i = 0; i < 8; i++)
302 hfs_dbg_cont(EXTENT, " %u:%u",
303 be32_to_cpu(extent[i].start_block),
304 be32_to_cpu(extent[i].block_count));
305 hfs_dbg_cont(EXTENT, "\n");
308 static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset,
309 u32 alloc_block, u32 block_count)
314 hfsplus_dump_extent(extent);
315 for (i = 0; i < 8; extent++, i++) {
316 count = be32_to_cpu(extent->block_count);
317 if (offset == count) {
318 start = be32_to_cpu(extent->start_block);
319 if (alloc_block != start + count) {
323 extent->start_block = cpu_to_be32(alloc_block);
325 block_count += count;
326 extent->block_count = cpu_to_be32(block_count);
328 } else if (offset < count)
336 static int hfsplus_free_extents(struct super_block *sb,
337 struct hfsplus_extent *extent,
338 u32 offset, u32 block_nr)
344 hfsplus_dump_extent(extent);
345 for (i = 0; i < 8; extent++, i++) {
346 count = be32_to_cpu(extent->block_count);
349 else if (offset < count)
357 start = be32_to_cpu(extent->start_block);
358 if (count <= block_nr) {
359 err = hfsplus_block_free(sb, start, count);
361 pr_err("can't free extent\n");
362 hfs_dbg(EXTENT, " start: %u count: %u\n",
365 extent->block_count = 0;
366 extent->start_block = 0;
370 err = hfsplus_block_free(sb, start + count, block_nr);
372 pr_err("can't free extent\n");
373 hfs_dbg(EXTENT, " start: %u count: %u\n",
376 extent->block_count = cpu_to_be32(count);
379 if (!block_nr || !i) {
381 * Try to free all extents and
382 * return only last error
388 count = be32_to_cpu(extent->block_count);
392 int hfsplus_free_fork(struct super_block *sb, u32 cnid,
393 struct hfsplus_fork_raw *fork, int type)
395 struct hfs_find_data fd;
396 hfsplus_extent_rec ext_entry;
397 u32 total_blocks, blocks, start;
400 total_blocks = be32_to_cpu(fork->total_blocks);
405 for (i = 0; i < 8; i++)
406 blocks += be32_to_cpu(fork->extents[i].block_count);
408 res = hfsplus_free_extents(sb, fork->extents, blocks, blocks);
411 if (total_blocks == blocks)
414 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
418 res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid,
422 start = be32_to_cpu(fd.key->ext.start_block);
423 hfsplus_free_extents(sb, ext_entry,
424 total_blocks - start,
426 hfs_brec_remove(&fd);
427 total_blocks = start;
428 } while (total_blocks > blocks);
434 int hfsplus_file_extend(struct inode *inode, bool zeroout)
436 struct super_block *sb = inode->i_sb;
437 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
438 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
439 u32 start, len, goal;
442 if (sbi->alloc_file->i_size * 8 <
443 sbi->total_blocks - sbi->free_blocks + 8) {
444 /* extend alloc file */
445 pr_err("extend alloc file! (%llu,%u,%u)\n",
446 sbi->alloc_file->i_size * 8,
447 sbi->total_blocks, sbi->free_blocks);
451 mutex_lock(&hip->extents_lock);
452 if (hip->alloc_blocks == hip->first_blocks)
453 goal = hfsplus_ext_lastblock(hip->first_extents);
455 res = hfsplus_ext_read_extent(inode, hip->alloc_blocks);
458 goal = hfsplus_ext_lastblock(hip->cached_extents);
461 len = hip->clump_blocks;
462 start = hfsplus_block_allocate(sb, sbi->total_blocks, goal, &len);
463 if (start >= sbi->total_blocks) {
464 start = hfsplus_block_allocate(sb, goal, 0, &len);
472 res = sb_issue_zeroout(sb, start, len, GFP_NOFS);
477 hfs_dbg(EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len);
479 if (hip->alloc_blocks <= hip->first_blocks) {
480 if (!hip->first_blocks) {
481 hfs_dbg(EXTENT, "first extents\n");
483 hip->first_extents[0].start_block = cpu_to_be32(start);
484 hip->first_extents[0].block_count = cpu_to_be32(len);
487 /* try to append to extents in inode */
488 res = hfsplus_add_extent(hip->first_extents,
495 hfsplus_dump_extent(hip->first_extents);
496 hip->first_blocks += len;
499 res = hfsplus_add_extent(hip->cached_extents,
500 hip->alloc_blocks - hip->cached_start,
503 hfsplus_dump_extent(hip->cached_extents);
504 hip->extent_state |= HFSPLUS_EXT_DIRTY;
505 hip->cached_blocks += len;
506 } else if (res == -ENOSPC)
511 hip->alloc_blocks += len;
512 mutex_unlock(&hip->extents_lock);
513 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);
516 mutex_unlock(&hip->extents_lock);
520 hfs_dbg(EXTENT, "insert new extent\n");
521 res = hfsplus_ext_write_extent_locked(inode);
525 memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
526 hip->cached_extents[0].start_block = cpu_to_be32(start);
527 hip->cached_extents[0].block_count = cpu_to_be32(len);
528 hfsplus_dump_extent(hip->cached_extents);
529 hip->extent_state |= HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW;
530 hip->cached_start = hip->alloc_blocks;
531 hip->cached_blocks = len;
537 void hfsplus_file_truncate(struct inode *inode)
539 struct super_block *sb = inode->i_sb;
540 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
541 struct hfs_find_data fd;
542 u32 alloc_cnt, blk_cnt, start;
545 hfs_dbg(INODE, "truncate: %lu, %llu -> %llu\n",
546 inode->i_ino, (long long)hip->phys_size, inode->i_size);
548 if (inode->i_size > hip->phys_size) {
549 struct address_space *mapping = inode->i_mapping;
552 loff_t size = inode->i_size;
554 res = pagecache_write_begin(NULL, mapping, size, 0,
555 AOP_FLAG_UNINTERRUPTIBLE,
559 res = pagecache_write_end(NULL, mapping, size,
563 mark_inode_dirty(inode);
565 } else if (inode->i_size == hip->phys_size)
568 blk_cnt = (inode->i_size + HFSPLUS_SB(sb)->alloc_blksz - 1) >>
569 HFSPLUS_SB(sb)->alloc_blksz_shift;
571 mutex_lock(&hip->extents_lock);
573 alloc_cnt = hip->alloc_blocks;
574 if (blk_cnt == alloc_cnt)
577 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
579 mutex_unlock(&hip->extents_lock);
580 /* XXX: We lack error handling of hfsplus_file_truncate() */
584 if (alloc_cnt == hip->first_blocks) {
585 hfsplus_free_extents(sb, hip->first_extents,
586 alloc_cnt, alloc_cnt - blk_cnt);
587 hfsplus_dump_extent(hip->first_extents);
588 hip->first_blocks = blk_cnt;
591 res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt);
594 start = hip->cached_start;
595 hfsplus_free_extents(sb, hip->cached_extents,
596 alloc_cnt - start, alloc_cnt - blk_cnt);
597 hfsplus_dump_extent(hip->cached_extents);
598 if (blk_cnt > start) {
599 hip->extent_state |= HFSPLUS_EXT_DIRTY;
603 hip->cached_start = hip->cached_blocks = 0;
604 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
605 hfs_brec_remove(&fd);
609 hip->alloc_blocks = blk_cnt;
611 mutex_unlock(&hip->extents_lock);
612 hip->phys_size = inode->i_size;
613 hip->fs_blocks = (inode->i_size + sb->s_blocksize - 1) >>
614 sb->s_blocksize_bits;
615 inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits);
616 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);