[PATCH 5.15 088/279] f2fs: compress: disallow disabling compress on non-empty compressed file

Greg Kroah-Hartman
2021-11-24T13:52:25Z

From: Hyeong-Jun Kim <hj514.kim@samsung.com>

[ Upstream commit 02d58cd253d7536c412993573fc6b3b4454960eb ]

Compresse file and normal file has differ in i_addr addressing,
specifically addrs per inode/block. So, we will face data loss, if we
disable the compression flag on non-empty files. Therefore we should
disallow not only enabling but disabling the compression flag on
non-empty files.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Hyeong-Jun Kim <hj514.kim@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/f2fs/f2fs.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b339ae89c1ad1..c242274e3479b 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4152,8 +4152,7 @@ static inline bool f2fs_disable_compressed_file(struct inode *inode)

if (!f2fs_compressed_file(inode))
return true;
- if (S_ISREG(inode->i_mode) &&
- (get_dirty_pages(inode) || atomic_read(&fi->i_compr_blocks)))
+ if (S_ISREG(inode->i_mode) && F2FS_HAS_BLOCKS(inode))
return false;

fi->i_flags &= ~F2FS_COMPR_FL;
--
2.33.0