diff options
Diffstat (limited to 'fs/btrfs/extent_io.c')
| -rw-r--r-- | fs/btrfs/extent_io.c | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 43af5a61ad25..02d05817cbdf 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1277,7 +1277,12 @@ int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, unsigned bits, gfp_t mask) { - return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask); + int wake = 0; + + if (bits & EXTENT_LOCKED) + wake = 1; + + return clear_extent_bit(tree, start, end, bits, wake, 0, NULL, mask); } int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, @@ -2767,8 +2772,6 @@ static int __must_check submit_one_bio(int rw, struct bio *bio, else btrfsic_submit_bio(rw, bio); - if (bio_flagged(bio, BIO_EOPNOTSUPP)) - ret = -EOPNOTSUPP; bio_put(bio); return ret; } @@ -4492,6 +4495,8 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, } if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) flags |= FIEMAP_EXTENT_ENCODED; + if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) + flags |= FIEMAP_EXTENT_UNWRITTEN; free_extent_map(em); em = NULL; @@ -4772,6 +4777,25 @@ struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info, start >> PAGE_CACHE_SHIFT); if (eb && atomic_inc_not_zero(&eb->refs)) { rcu_read_unlock(); + /* + * Lock our eb's refs_lock to avoid races with + * free_extent_buffer. When we get our eb it might be flagged + * with EXTENT_BUFFER_STALE and another task running + * free_extent_buffer might have seen that flag set, + * eb->refs == 2, that the buffer isn't under IO (dirty and + * writeback flags not set) and it's still in the tree (flag + * EXTENT_BUFFER_TREE_REF set), therefore being in the process + * of decrementing the extent buffer's reference count twice. + * So here we could race and increment the eb's reference count, + * clear its stale flag, mark it as dirty and drop our reference + * before the other task finishes executing free_extent_buffer, + * which would later result in an attempt to free an extent + * buffer that is dirty. + */ + if (test_bit(EXTENT_BUFFER_STALE, &eb->bflags)) { + spin_lock(&eb->refs_lock); + spin_unlock(&eb->refs_lock); + } mark_extent_buffer_accessed(eb, NULL); return eb; } |