diff options
-rw-r--r-- | fs/btrfs/file.c | 94 |
1 files changed, 19 insertions, 75 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 72da4df53c9a..bf3465cf455a 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2405,14 +2405,12 @@ out_reserve_fail: static int find_desired_extent(struct inode *inode, loff_t *offset, int whence) { struct btrfs_root *root = BTRFS_I(inode)->root; - struct extent_map *em; + struct extent_map *em = NULL; struct extent_state *cached_state = NULL; u64 lockstart = *offset; u64 lockend = i_size_read(inode); u64 start = *offset; - u64 orig_start = *offset; u64 len = i_size_read(inode); - u64 last_end = 0; int ret = 0; lockend = max_t(u64, root->sectorsize, lockend); @@ -2429,89 +2427,35 @@ static int find_desired_extent(struct inode *inode, loff_t *offset, int whence) lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0, &cached_state); - /* - * Delalloc is such a pain. If we have a hole and we have pending - * delalloc for a portion of the hole we will get back a hole that - * exists for the entire range since it hasn't been actually written - * yet. So to take care of this case we need to look for an extent just - * before the position we want in case there is outstanding delalloc - * going on here. - */ - if (whence == SEEK_HOLE && start != 0) { - if (start <= root->sectorsize) - em = btrfs_get_extent_fiemap(inode, NULL, 0, 0, - root->sectorsize, 0); - else - em = btrfs_get_extent_fiemap(inode, NULL, 0, - start - root->sectorsize, - root->sectorsize, 0); - if (IS_ERR(em)) { - ret = PTR_ERR(em); - goto out; - } - last_end = em->start + em->len; - if (em->block_start == EXTENT_MAP_DELALLOC) - last_end = min_t(u64, last_end, inode->i_size); - free_extent_map(em); - } - - while (1) { + while (start < inode->i_size) { em = btrfs_get_extent_fiemap(inode, NULL, 0, start, len, 0); if (IS_ERR(em)) { ret = PTR_ERR(em); + em = NULL; break; } - if (em->block_start == EXTENT_MAP_HOLE) { - if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) { - if (last_end <= orig_start) { - free_extent_map(em); - ret = -ENXIO; - break; - } - } - - if (whence == SEEK_HOLE) { - *offset = start; - free_extent_map(em); - break; - } - } else { - if (whence == SEEK_DATA) { - if (em->block_start == EXTENT_MAP_DELALLOC) { - if (start >= inode->i_size) { - free_extent_map(em); - ret = -ENXIO; - break; - } - } - - if (!test_bit(EXTENT_FLAG_PREALLOC, - &em->flags)) { - *offset = start; - free_extent_map(em); - break; - } - } - } + if (whence == SEEK_HOLE && + (em->block_start == EXTENT_MAP_HOLE || + test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) + break; + else if (whence == SEEK_DATA && + (em->block_start != EXTENT_MAP_HOLE && + !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) + break; start = em->start + em->len; - last_end = em->start + em->len; - - if (em->block_start == EXTENT_MAP_DELALLOC) - last_end = min_t(u64, last_end, inode->i_size); - - if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) { - free_extent_map(em); - ret = -ENXIO; - break; - } free_extent_map(em); + em = NULL; cond_resched(); } - if (!ret) - *offset = min(*offset, inode->i_size); -out: + free_extent_map(em); + if (!ret) { + if (whence == SEEK_DATA && start >= inode->i_size) + ret = -ENXIO; + else + *offset = min_t(loff_t, start, inode->i_size); + } unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state, GFP_NOFS); return ret; |