diff options
| author | Filipe Manana <fdmanana@suse.com> | 2023-02-27 15:53:56 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-17 10:57:56 +0300 |
| commit | 895c7c45f45f7c8263b3e9f4a2a8ad754beea4bd (patch) | |
| tree | e8095820ecc03653c922c43980a03b013818dd3e | |
| parent | 58662cfb459150b9c0c22d20cddaea439b3844bd (diff) | |
| download | linux-895c7c45f45f7c8263b3e9f4a2a8ad754beea4bd.tar.xz | |
btrfs: fix extent map logging bit not cleared for split maps after dropping range
[ Upstream commit e4cc1483f35940c9288c332dd275f6fad485f8d2 ]
At btrfs_drop_extent_map_range() we are clearing the EXTENT_FLAG_LOGGING
bit on a 'flags' variable that was not initialized. This makes static
checkers complain about it, so initialize the 'flags' variable before
clearing the bit.
In practice this has no consequences, because EXTENT_FLAG_LOGGING should
not be set when btrfs_drop_extent_map_range() is called, as an fsync locks
the inode in exclusive mode, locks the inode's mmap semaphore in exclusive
mode too and it always flushes all delalloc.
Also add a comment about why we clear EXTENT_FLAG_LOGGING on a copy of the
flags of the split extent map.
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/Y%2FyipSVozUDEZKow@kili/
Fixes: db21370bffbc ("btrfs: drop extent map range more efficiently")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/btrfs/extent_map.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index be94030e1dfb..138afa955370 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -763,7 +763,13 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end, goto next; } + flags = em->flags; clear_bit(EXTENT_FLAG_PINNED, &em->flags); + /* + * In case we split the extent map, we want to preserve the + * EXTENT_FLAG_LOGGING flag on our extent map, but we don't want + * it on the new extent maps. + */ clear_bit(EXTENT_FLAG_LOGGING, &flags); modified = !list_empty(&em->list); @@ -774,7 +780,6 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end, if (em->start >= start && em_end <= end) goto remove_em; - flags = em->flags; gen = em->generation; compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |