Merge tag 'renesas-phy-rcar-usb-for-v3.11' of git://git.kernel.org/pub/scm/linux...
[linux-2.6.git] / fs / hfsplus / extents.c
blobfbb212fbb1efbfee64443bd3fe5f039fbf28426a
1 /*
2 * linux/fs/hfsplus/extents.c
4 * Copyright (C) 2001
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
9 */
11 #include <linux/errno.h>
12 #include <linux/fs.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)
22 __be32 k1id, k2id;
23 __be32 k1s, k2s;
25 k1id = k1->ext.cnid;
26 k2id = k2->ext.cnid;
27 if (k1id != k2id)
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;
35 if (k1s == k2s)
36 return 0;
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,
41 u32 block, u8 type)
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;
47 key->ext.pad = 0;
50 static u32 hfsplus_ext_find_block(struct hfsplus_extent *ext, u32 off)
52 int i;
53 u32 count;
55 for (i = 0; i < 8; ext++, i++) {
56 count = be32_to_cpu(ext->block_count);
57 if (off < count)
58 return be32_to_cpu(ext->start_block) + off;
59 off -= count;
61 /* panic? */
62 return 0;
65 static int hfsplus_ext_block_count(struct hfsplus_extent *ext)
67 int i;
68 u32 count = 0;
70 for (i = 0; i < 8; ext++, i++)
71 count += be32_to_cpu(ext->block_count);
72 return count;
75 static u32 hfsplus_ext_lastblock(struct hfsplus_extent *ext)
77 int i;
79 ext += 7;
80 for (i = 0; i < 7; ext--, i++)
81 if (ext->block_count)
82 break;
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);
90 int res;
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) {
100 if (res != -ENOENT)
101 return res;
102 hfs_brec_insert(fd, hip->cached_extents,
103 sizeof(hfsplus_extent_rec));
104 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
105 } else {
106 if (res)
107 return res;
108 hfs_bnode_write(fd->bnode, hip->cached_extents,
109 fd->entryoffset, fd->entrylength);
110 hip->extent_state &= ~HFSPLUS_EXT_DIRTY;
114 * We can't just use hfsplus_mark_inode_dirty here, because we
115 * also get called from hfsplus_write_inode, which should not
116 * redirty the inode. Instead the callers have to be careful
117 * to explicily mark the inode dirty, too.
119 set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags);
121 return 0;
124 static int hfsplus_ext_write_extent_locked(struct inode *inode)
126 int res = 0;
128 if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) {
129 struct hfs_find_data fd;
131 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
132 if (res)
133 return res;
134 res = __hfsplus_ext_write_extent(inode, &fd);
135 hfs_find_exit(&fd);
137 return res;
140 int hfsplus_ext_write_extent(struct inode *inode)
142 int res;
144 mutex_lock(&HFSPLUS_I(inode)->extents_lock);
145 res = hfsplus_ext_write_extent_locked(inode);
146 mutex_unlock(&HFSPLUS_I(inode)->extents_lock);
148 return res;
151 static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd,
152 struct hfsplus_extent *extent,
153 u32 cnid, u32 block, u8 type)
155 int res;
157 hfsplus_ext_build_key(fd->search_key, cnid, block, type);
158 fd->key->ext.cnid = 0;
159 res = hfs_brec_find(fd, hfs_find_rec_by_key);
160 if (res && res != -ENOENT)
161 return res;
162 if (fd->key->ext.cnid != fd->search_key->ext.cnid ||
163 fd->key->ext.fork_type != fd->search_key->ext.fork_type)
164 return -ENOENT;
165 if (fd->entrylength != sizeof(hfsplus_extent_rec))
166 return -EIO;
167 hfs_bnode_read(fd->bnode, extent, fd->entryoffset,
168 sizeof(hfsplus_extent_rec));
169 return 0;
172 static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd,
173 struct inode *inode, u32 block)
175 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
176 int res;
178 WARN_ON(!mutex_is_locked(&hip->extents_lock));
180 if (hip->extent_state & HFSPLUS_EXT_DIRTY) {
181 res = __hfsplus_ext_write_extent(inode, fd);
182 if (res)
183 return res;
186 res = __hfsplus_ext_read_extent(fd, hip->cached_extents, inode->i_ino,
187 block, HFSPLUS_IS_RSRC(inode) ?
188 HFSPLUS_TYPE_RSRC :
189 HFSPLUS_TYPE_DATA);
190 if (!res) {
191 hip->cached_start = be32_to_cpu(fd->key->ext.start_block);
192 hip->cached_blocks =
193 hfsplus_ext_block_count(hip->cached_extents);
194 } else {
195 hip->cached_start = hip->cached_blocks = 0;
196 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
198 return res;
201 static int hfsplus_ext_read_extent(struct inode *inode, u32 block)
203 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
204 struct hfs_find_data fd;
205 int res;
207 if (block >= hip->cached_start &&
208 block < hip->cached_start + hip->cached_blocks)
209 return 0;
211 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
212 if (!res) {
213 res = __hfsplus_ext_cache_extent(&fd, inode, block);
214 hfs_find_exit(&fd);
216 return res;
219 /* Get a block at iblock for inode, possibly allocating if create */
220 int hfsplus_get_block(struct inode *inode, sector_t iblock,
221 struct buffer_head *bh_result, int create)
223 struct super_block *sb = inode->i_sb;
224 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
225 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
226 int res = -EIO;
227 u32 ablock, dblock, mask;
228 sector_t sector;
229 int was_dirty = 0;
230 int shift;
232 /* Convert inode block to disk allocation block */
233 shift = sbi->alloc_blksz_shift - sb->s_blocksize_bits;
234 ablock = iblock >> sbi->fs_shift;
236 if (iblock >= hip->fs_blocks) {
237 if (iblock > hip->fs_blocks || !create)
238 return -EIO;
239 if (ablock >= hip->alloc_blocks) {
240 res = hfsplus_file_extend(inode);
241 if (res)
242 return res;
244 } else
245 create = 0;
247 if (ablock < hip->first_blocks) {
248 dblock = hfsplus_ext_find_block(hip->first_extents, ablock);
249 goto done;
252 if (inode->i_ino == HFSPLUS_EXT_CNID)
253 return -EIO;
255 mutex_lock(&hip->extents_lock);
258 * hfsplus_ext_read_extent will write out a cached extent into
259 * the extents btree. In that case we may have to mark the inode
260 * dirty even for a pure read of an extent here.
262 was_dirty = (hip->extent_state & HFSPLUS_EXT_DIRTY);
263 res = hfsplus_ext_read_extent(inode, ablock);
264 if (res) {
265 mutex_unlock(&hip->extents_lock);
266 return -EIO;
268 dblock = hfsplus_ext_find_block(hip->cached_extents,
269 ablock - hip->cached_start);
270 mutex_unlock(&hip->extents_lock);
272 done:
273 hfs_dbg(EXTENT, "get_block(%lu): %llu - %u\n",
274 inode->i_ino, (long long)iblock, dblock);
276 mask = (1 << sbi->fs_shift) - 1;
277 sector = ((sector_t)dblock << sbi->fs_shift) +
278 sbi->blockoffset + (iblock & mask);
279 map_bh(bh_result, sb, sector);
281 if (create) {
282 set_buffer_new(bh_result);
283 hip->phys_size += sb->s_blocksize;
284 hip->fs_blocks++;
285 inode_add_bytes(inode, sb->s_blocksize);
287 if (create || was_dirty)
288 mark_inode_dirty(inode);
289 return 0;
292 static void hfsplus_dump_extent(struct hfsplus_extent *extent)
294 int i;
296 hfs_dbg(EXTENT, " ");
297 for (i = 0; i < 8; i++)
298 hfs_dbg_cont(EXTENT, " %u:%u",
299 be32_to_cpu(extent[i].start_block),
300 be32_to_cpu(extent[i].block_count));
301 hfs_dbg_cont(EXTENT, "\n");
304 static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset,
305 u32 alloc_block, u32 block_count)
307 u32 count, start;
308 int i;
310 hfsplus_dump_extent(extent);
311 for (i = 0; i < 8; extent++, i++) {
312 count = be32_to_cpu(extent->block_count);
313 if (offset == count) {
314 start = be32_to_cpu(extent->start_block);
315 if (alloc_block != start + count) {
316 if (++i >= 8)
317 return -ENOSPC;
318 extent++;
319 extent->start_block = cpu_to_be32(alloc_block);
320 } else
321 block_count += count;
322 extent->block_count = cpu_to_be32(block_count);
323 return 0;
324 } else if (offset < count)
325 break;
326 offset -= count;
328 /* panic? */
329 return -EIO;
332 static int hfsplus_free_extents(struct super_block *sb,
333 struct hfsplus_extent *extent,
334 u32 offset, u32 block_nr)
336 u32 count, start;
337 int i;
338 int err = 0;
340 hfsplus_dump_extent(extent);
341 for (i = 0; i < 8; extent++, i++) {
342 count = be32_to_cpu(extent->block_count);
343 if (offset == count)
344 goto found;
345 else if (offset < count)
346 break;
347 offset -= count;
349 /* panic? */
350 return -EIO;
351 found:
352 for (;;) {
353 start = be32_to_cpu(extent->start_block);
354 if (count <= block_nr) {
355 err = hfsplus_block_free(sb, start, count);
356 if (err) {
357 pr_err("can't free extent\n");
358 hfs_dbg(EXTENT, " start: %u count: %u\n",
359 start, count);
361 extent->block_count = 0;
362 extent->start_block = 0;
363 block_nr -= count;
364 } else {
365 count -= block_nr;
366 err = hfsplus_block_free(sb, start + count, block_nr);
367 if (err) {
368 pr_err("can't free extent\n");
369 hfs_dbg(EXTENT, " start: %u count: %u\n",
370 start, count);
372 extent->block_count = cpu_to_be32(count);
373 block_nr = 0;
375 if (!block_nr || !i) {
377 * Try to free all extents and
378 * return only last error
380 return err;
382 i--;
383 extent--;
384 count = be32_to_cpu(extent->block_count);
388 int hfsplus_free_fork(struct super_block *sb, u32 cnid,
389 struct hfsplus_fork_raw *fork, int type)
391 struct hfs_find_data fd;
392 hfsplus_extent_rec ext_entry;
393 u32 total_blocks, blocks, start;
394 int res, i;
396 total_blocks = be32_to_cpu(fork->total_blocks);
397 if (!total_blocks)
398 return 0;
400 blocks = 0;
401 for (i = 0; i < 8; i++)
402 blocks += be32_to_cpu(fork->extents[i].block_count);
404 res = hfsplus_free_extents(sb, fork->extents, blocks, blocks);
405 if (res)
406 return res;
407 if (total_blocks == blocks)
408 return 0;
410 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
411 if (res)
412 return res;
413 do {
414 res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid,
415 total_blocks, type);
416 if (res)
417 break;
418 start = be32_to_cpu(fd.key->ext.start_block);
419 hfsplus_free_extents(sb, ext_entry,
420 total_blocks - start,
421 total_blocks);
422 hfs_brec_remove(&fd);
423 total_blocks = start;
424 } while (total_blocks > blocks);
425 hfs_find_exit(&fd);
427 return res;
430 int hfsplus_file_extend(struct inode *inode)
432 struct super_block *sb = inode->i_sb;
433 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
434 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
435 u32 start, len, goal;
436 int res;
438 if (sbi->alloc_file->i_size * 8 <
439 sbi->total_blocks - sbi->free_blocks + 8) {
440 /* extend alloc file */
441 pr_err("extend alloc file! "
442 "(%llu,%u,%u)\n",
443 sbi->alloc_file->i_size * 8,
444 sbi->total_blocks, sbi->free_blocks);
445 return -ENOSPC;
448 mutex_lock(&hip->extents_lock);
449 if (hip->alloc_blocks == hip->first_blocks)
450 goal = hfsplus_ext_lastblock(hip->first_extents);
451 else {
452 res = hfsplus_ext_read_extent(inode, hip->alloc_blocks);
453 if (res)
454 goto out;
455 goal = hfsplus_ext_lastblock(hip->cached_extents);
458 len = hip->clump_blocks;
459 start = hfsplus_block_allocate(sb, sbi->total_blocks, goal, &len);
460 if (start >= sbi->total_blocks) {
461 start = hfsplus_block_allocate(sb, goal, 0, &len);
462 if (start >= goal) {
463 res = -ENOSPC;
464 goto out;
468 hfs_dbg(EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len);
470 if (hip->alloc_blocks <= hip->first_blocks) {
471 if (!hip->first_blocks) {
472 hfs_dbg(EXTENT, "first extents\n");
473 /* no extents yet */
474 hip->first_extents[0].start_block = cpu_to_be32(start);
475 hip->first_extents[0].block_count = cpu_to_be32(len);
476 res = 0;
477 } else {
478 /* try to append to extents in inode */
479 res = hfsplus_add_extent(hip->first_extents,
480 hip->alloc_blocks,
481 start, len);
482 if (res == -ENOSPC)
483 goto insert_extent;
485 if (!res) {
486 hfsplus_dump_extent(hip->first_extents);
487 hip->first_blocks += len;
489 } else {
490 res = hfsplus_add_extent(hip->cached_extents,
491 hip->alloc_blocks - hip->cached_start,
492 start, len);
493 if (!res) {
494 hfsplus_dump_extent(hip->cached_extents);
495 hip->extent_state |= HFSPLUS_EXT_DIRTY;
496 hip->cached_blocks += len;
497 } else if (res == -ENOSPC)
498 goto insert_extent;
500 out:
501 mutex_unlock(&hip->extents_lock);
502 if (!res) {
503 hip->alloc_blocks += len;
504 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);
506 return res;
508 insert_extent:
509 hfs_dbg(EXTENT, "insert new extent\n");
510 res = hfsplus_ext_write_extent_locked(inode);
511 if (res)
512 goto out;
514 memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
515 hip->cached_extents[0].start_block = cpu_to_be32(start);
516 hip->cached_extents[0].block_count = cpu_to_be32(len);
517 hfsplus_dump_extent(hip->cached_extents);
518 hip->extent_state |= HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW;
519 hip->cached_start = hip->alloc_blocks;
520 hip->cached_blocks = len;
522 res = 0;
523 goto out;
526 void hfsplus_file_truncate(struct inode *inode)
528 struct super_block *sb = inode->i_sb;
529 struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
530 struct hfs_find_data fd;
531 u32 alloc_cnt, blk_cnt, start;
532 int res;
534 hfs_dbg(INODE, "truncate: %lu, %llu -> %llu\n",
535 inode->i_ino, (long long)hip->phys_size, inode->i_size);
537 if (inode->i_size > hip->phys_size) {
538 struct address_space *mapping = inode->i_mapping;
539 struct page *page;
540 void *fsdata;
541 loff_t size = inode->i_size;
543 res = pagecache_write_begin(NULL, mapping, size, 0,
544 AOP_FLAG_UNINTERRUPTIBLE,
545 &page, &fsdata);
546 if (res)
547 return;
548 res = pagecache_write_end(NULL, mapping, size,
549 0, 0, page, fsdata);
550 if (res < 0)
551 return;
552 mark_inode_dirty(inode);
553 return;
554 } else if (inode->i_size == hip->phys_size)
555 return;
557 blk_cnt = (inode->i_size + HFSPLUS_SB(sb)->alloc_blksz - 1) >>
558 HFSPLUS_SB(sb)->alloc_blksz_shift;
559 alloc_cnt = hip->alloc_blocks;
560 if (blk_cnt == alloc_cnt)
561 goto out;
563 mutex_lock(&hip->extents_lock);
564 res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
565 if (res) {
566 mutex_unlock(&hip->extents_lock);
567 /* XXX: We lack error handling of hfsplus_file_truncate() */
568 return;
570 while (1) {
571 if (alloc_cnt == hip->first_blocks) {
572 hfsplus_free_extents(sb, hip->first_extents,
573 alloc_cnt, alloc_cnt - blk_cnt);
574 hfsplus_dump_extent(hip->first_extents);
575 hip->first_blocks = blk_cnt;
576 break;
578 res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt);
579 if (res)
580 break;
581 start = hip->cached_start;
582 hfsplus_free_extents(sb, hip->cached_extents,
583 alloc_cnt - start, alloc_cnt - blk_cnt);
584 hfsplus_dump_extent(hip->cached_extents);
585 if (blk_cnt > start) {
586 hip->extent_state |= HFSPLUS_EXT_DIRTY;
587 break;
589 alloc_cnt = start;
590 hip->cached_start = hip->cached_blocks = 0;
591 hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
592 hfs_brec_remove(&fd);
594 hfs_find_exit(&fd);
595 mutex_unlock(&hip->extents_lock);
597 hip->alloc_blocks = blk_cnt;
598 out:
599 hip->phys_size = inode->i_size;
600 hip->fs_blocks = (inode->i_size + sb->s_blocksize - 1) >>
601 sb->s_blocksize_bits;
602 inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits);
603 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);