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>
14 #include <linux/version.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(hfsplus_btree_key *k1, 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 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 void __hfsplus_ext_write_extent(struct inode *inode, struct hfs_find_data *fd)
90 hfsplus_ext_build_key(fd->search_key, inode->i_ino, HFSPLUS_I(inode).cached_start,
91 HFSPLUS_IS_RSRC(inode) ? HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
92 res = hfs_brec_find(fd);
93 if (HFSPLUS_I(inode).flags & HFSPLUS_FLG_EXT_NEW) {
96 hfs_brec_insert(fd, HFSPLUS_I(inode).cached_extents, sizeof(hfsplus_extent_rec));
97 HFSPLUS_I(inode).flags &= ~(HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW);
101 hfs_bnode_write(fd->bnode, HFSPLUS_I(inode).cached_extents, fd->entryoffset, fd->entrylength);
102 HFSPLUS_I(inode).flags &= ~HFSPLUS_FLG_EXT_DIRTY;
106 void hfsplus_ext_write_extent(struct inode *inode)
108 if (HFSPLUS_I(inode).flags & HFSPLUS_FLG_EXT_DIRTY) {
109 struct hfs_find_data fd;
111 hfs_find_init(HFSPLUS_SB(inode->i_sb).ext_tree, &fd);
112 __hfsplus_ext_write_extent(inode, &fd);
117 static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd,
118 struct hfsplus_extent *extent,
119 u32 cnid, u32 block, u8 type)
123 hfsplus_ext_build_key(fd->search_key, cnid, block, type);
124 fd->key->ext.cnid = 0;
125 res = hfs_brec_find(fd);
126 if (res && res != -ENOENT)
128 if (fd->key->ext.cnid != fd->search_key->ext.cnid ||
129 fd->key->ext.fork_type != fd->search_key->ext.fork_type)
131 if (fd->entrylength != sizeof(hfsplus_extent_rec))
133 hfs_bnode_read(fd->bnode, extent, fd->entryoffset, sizeof(hfsplus_extent_rec));
137 static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd, struct inode *inode, u32 block)
141 if (HFSPLUS_I(inode).flags & HFSPLUS_FLG_EXT_DIRTY)
142 __hfsplus_ext_write_extent(inode, fd);
144 res = __hfsplus_ext_read_extent(fd, HFSPLUS_I(inode).cached_extents, inode->i_ino,
145 block, HFSPLUS_IS_RSRC(inode) ? HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
147 HFSPLUS_I(inode).cached_start = be32_to_cpu(fd->key->ext.start_block);
148 HFSPLUS_I(inode).cached_blocks = hfsplus_ext_block_count(HFSPLUS_I(inode).cached_extents);
150 HFSPLUS_I(inode).cached_start = HFSPLUS_I(inode).cached_blocks = 0;
151 HFSPLUS_I(inode).flags &= ~(HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW);
156 static int hfsplus_ext_read_extent(struct inode *inode, u32 block)
158 struct hfs_find_data fd;
161 if (block >= HFSPLUS_I(inode).cached_start &&
162 block < HFSPLUS_I(inode).cached_start + HFSPLUS_I(inode).cached_blocks)
165 hfs_find_init(HFSPLUS_SB(inode->i_sb).ext_tree, &fd);
166 res = __hfsplus_ext_cache_extent(&fd, inode, block);
171 /* Get a block at iblock for inode, possibly allocating if create */
172 int hfsplus_get_block(struct inode *inode, sector_t iblock,
173 struct buffer_head *bh_result, int create)
175 struct super_block *sb;
177 u32 ablock, dblock, mask;
182 /* Convert inode block to disk allocation block */
183 shift = HFSPLUS_SB(sb).alloc_blksz_shift - sb->s_blocksize_bits;
184 ablock = iblock >> HFSPLUS_SB(sb).fs_shift;
186 if (iblock >= inode->i_blocks) {
187 if (iblock > inode->i_blocks || !create)
189 if (ablock >= HFSPLUS_I(inode).alloc_blocks) {
190 res = hfsplus_file_extend(inode);
197 if (ablock < HFSPLUS_I(inode).first_blocks) {
198 dblock = hfsplus_ext_find_block(HFSPLUS_I(inode).first_extents, ablock);
202 down(&HFSPLUS_I(inode).extents_lock);
203 res = hfsplus_ext_read_extent(inode, ablock);
205 dblock = hfsplus_ext_find_block(HFSPLUS_I(inode).cached_extents, ablock -
206 HFSPLUS_I(inode).cached_start);
208 up(&HFSPLUS_I(inode).extents_lock);
211 up(&HFSPLUS_I(inode).extents_lock);
214 dprint(DBG_EXTENT, "get_block(%lu): %llu - %u\n", inode->i_ino, (long long)iblock, dblock);
215 mask = (1 << HFSPLUS_SB(sb).fs_shift) - 1;
216 map_bh(bh_result, sb, (dblock << HFSPLUS_SB(sb).fs_shift) + HFSPLUS_SB(sb).blockoffset + (iblock & mask));
218 set_buffer_new(bh_result);
219 HFSPLUS_I(inode).phys_size += sb->s_blocksize;
221 mark_inode_dirty(inode);
226 static void hfsplus_dump_extent(struct hfsplus_extent *extent)
230 dprint(DBG_EXTENT, " ");
231 for (i = 0; i < 8; i++)
232 dprint(DBG_EXTENT, " %u:%u", be32_to_cpu(extent[i].start_block),
233 be32_to_cpu(extent[i].block_count));
234 dprint(DBG_EXTENT, "\n");
237 static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset,
238 u32 alloc_block, u32 block_count)
243 hfsplus_dump_extent(extent);
244 for (i = 0; i < 8; extent++, i++) {
245 count = be32_to_cpu(extent->block_count);
246 if (offset == count) {
247 start = be32_to_cpu(extent->start_block);
248 if (alloc_block != start + count) {
252 extent->start_block = cpu_to_be32(alloc_block);
254 block_count += count;
255 extent->block_count = cpu_to_be32(block_count);
257 } else if (offset < count)
265 int hfsplus_free_extents(struct super_block *sb, struct hfsplus_extent *extent,
266 u32 offset, u32 block_nr)
271 hfsplus_dump_extent(extent);
272 for (i = 0; i < 8; extent++, i++) {
273 count = be32_to_cpu(extent->block_count);
276 else if (offset < count)
284 start = be32_to_cpu(extent->start_block);
285 if (count <= block_nr) {
286 hfsplus_block_free(sb, start, count);
287 extent->block_count = 0;
288 extent->start_block = 0;
292 hfsplus_block_free(sb, start + count, block_nr);
293 extent->block_count = cpu_to_be32(count);
300 count = be32_to_cpu(extent->block_count);
304 int hfsplus_free_fork(struct super_block *sb, u32 cnid, struct hfsplus_fork_raw *fork, int type)
306 struct hfs_find_data fd;
307 hfsplus_extent_rec ext_entry;
308 u32 total_blocks, blocks, start;
311 total_blocks = be32_to_cpu(fork->total_blocks);
316 for (i = 0; i < 8; i++)
317 blocks += be32_to_cpu(fork->extents[i].block_count);
319 res = hfsplus_free_extents(sb, fork->extents, blocks, blocks);
322 if (total_blocks == blocks)
325 hfs_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
327 res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid,
331 start = be32_to_cpu(fd.key->ext.start_block);
332 hfsplus_free_extents(sb, ext_entry,
333 total_blocks - start,
335 hfs_brec_remove(&fd);
336 total_blocks = start;
337 } while (total_blocks > blocks);
343 int hfsplus_file_extend(struct inode *inode)
345 struct super_block *sb = inode->i_sb;
346 u32 start, len, goal;
349 if (HFSPLUS_SB(sb).alloc_file->i_size * 8 < HFSPLUS_SB(sb).total_blocks - HFSPLUS_SB(sb).free_blocks + 8) {
351 printk("extend alloc file! (%Lu,%u,%u)\n", HFSPLUS_SB(sb).alloc_file->i_size * 8,
352 HFSPLUS_SB(sb).total_blocks, HFSPLUS_SB(sb).free_blocks);
357 down(&HFSPLUS_I(inode).extents_lock);
358 if (HFSPLUS_I(inode).alloc_blocks == HFSPLUS_I(inode).first_blocks)
359 goal = hfsplus_ext_lastblock(HFSPLUS_I(inode).first_extents);
361 res = hfsplus_ext_read_extent(inode, HFSPLUS_I(inode).alloc_blocks);
364 goal = hfsplus_ext_lastblock(HFSPLUS_I(inode).cached_extents);
367 len = HFSPLUS_I(inode).clump_blocks;
368 start = hfsplus_block_allocate(sb, HFSPLUS_SB(sb).total_blocks, goal, &len);
369 if (start >= HFSPLUS_SB(sb).total_blocks) {
370 start = hfsplus_block_allocate(sb, goal, 0, &len);
377 dprint(DBG_EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len);
378 if (HFSPLUS_I(inode).alloc_blocks <= HFSPLUS_I(inode).first_blocks) {
379 if (!HFSPLUS_I(inode).first_blocks) {
380 dprint(DBG_EXTENT, "first extents\n");
382 HFSPLUS_I(inode).first_extents[0].start_block = cpu_to_be32(start);
383 HFSPLUS_I(inode).first_extents[0].block_count = cpu_to_be32(len);
386 /* try to append to extents in inode */
387 res = hfsplus_add_extent(HFSPLUS_I(inode).first_extents,
388 HFSPLUS_I(inode).alloc_blocks,
394 hfsplus_dump_extent(HFSPLUS_I(inode).first_extents);
395 HFSPLUS_I(inode).first_blocks += len;
398 res = hfsplus_add_extent(HFSPLUS_I(inode).cached_extents,
399 HFSPLUS_I(inode).alloc_blocks -
400 HFSPLUS_I(inode).cached_start,
403 hfsplus_dump_extent(HFSPLUS_I(inode).cached_extents);
404 HFSPLUS_I(inode).flags |= HFSPLUS_FLG_EXT_DIRTY;
405 HFSPLUS_I(inode).cached_blocks += len;
406 } else if (res == -ENOSPC)
410 up(&HFSPLUS_I(inode).extents_lock);
412 HFSPLUS_I(inode).alloc_blocks += len;
413 mark_inode_dirty(inode);
418 dprint(DBG_EXTENT, "insert new extent\n");
419 hfsplus_ext_write_extent(inode);
421 memset(HFSPLUS_I(inode).cached_extents, 0, sizeof(hfsplus_extent_rec));
422 HFSPLUS_I(inode).cached_extents[0].start_block = cpu_to_be32(start);
423 HFSPLUS_I(inode).cached_extents[0].block_count = cpu_to_be32(len);
424 hfsplus_dump_extent(HFSPLUS_I(inode).cached_extents);
425 HFSPLUS_I(inode).flags |= HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW;
426 HFSPLUS_I(inode).cached_start = HFSPLUS_I(inode).alloc_blocks;
427 HFSPLUS_I(inode).cached_blocks = len;
433 void hfsplus_file_truncate(struct inode *inode)
435 struct super_block *sb = inode->i_sb;
436 struct hfs_find_data fd;
437 u32 alloc_cnt, blk_cnt, start;
440 dprint(DBG_INODE, "truncate: %lu, %Lu -> %Lu\n", inode->i_ino,
441 (long long)HFSPLUS_I(inode).phys_size, inode->i_size);
442 if (inode->i_size > HFSPLUS_I(inode).phys_size) {
443 struct address_space *mapping = inode->i_mapping;
445 u32 size = inode->i_size - 1;
448 page = grab_cache_page(mapping, size >> PAGE_CACHE_SHIFT);
451 size &= PAGE_CACHE_SIZE - 1;
453 res = mapping->a_ops->prepare_write(NULL, page, size, size);
455 res = mapping->a_ops->commit_write(NULL, page, size, size);
457 inode->i_size = HFSPLUS_I(inode).phys_size;
459 page_cache_release(page);
460 mark_inode_dirty(inode);
463 blk_cnt = (inode->i_size + HFSPLUS_SB(sb).alloc_blksz - 1) >> HFSPLUS_SB(sb).alloc_blksz_shift;
464 alloc_cnt = HFSPLUS_I(inode).alloc_blocks;
465 if (blk_cnt == alloc_cnt)
468 down(&HFSPLUS_I(inode).extents_lock);
469 hfs_find_init(HFSPLUS_SB(sb).ext_tree, &fd);
471 if (alloc_cnt == HFSPLUS_I(inode).first_blocks) {
472 hfsplus_free_extents(sb, HFSPLUS_I(inode).first_extents,
473 alloc_cnt, alloc_cnt - blk_cnt);
474 hfsplus_dump_extent(HFSPLUS_I(inode).first_extents);
475 HFSPLUS_I(inode).first_blocks = blk_cnt;
478 res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt);
481 start = HFSPLUS_I(inode).cached_start;
482 hfsplus_free_extents(sb, HFSPLUS_I(inode).cached_extents,
483 alloc_cnt - start, alloc_cnt - blk_cnt);
484 hfsplus_dump_extent(HFSPLUS_I(inode).cached_extents);
485 if (blk_cnt > start) {
486 HFSPLUS_I(inode).flags |= HFSPLUS_FLG_EXT_DIRTY;
490 HFSPLUS_I(inode).cached_start = HFSPLUS_I(inode).cached_blocks = 0;
491 HFSPLUS_I(inode).flags &= ~(HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW);
492 hfs_brec_remove(&fd);
495 up(&HFSPLUS_I(inode).extents_lock);
497 HFSPLUS_I(inode).alloc_blocks = blk_cnt;
499 HFSPLUS_I(inode).phys_size = inode->i_size;
500 mark_inode_dirty(inode);
501 inode->i_blocks = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;