f2fs: Prevent swap file in LFS mode
The kernel writes to swap files on f2fs directly without the assistance
of the filesystem. This direct write by kernel can be non-sequential
even when the f2fs is in LFS mode. Such non-sequential write conflicts
with the LFS semantics. Especially when f2fs is set up on zoned block
devices, the non-sequential write causes unaligned write command errors.
To avoid the non-sequential writes to swap files, prevent swap file
activation when the filesystem is in LFS mode.
Fixes: 4969c06a0d83 ("f2fs: support swap file w/ DIO")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.10+
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index d352f2b..d4795ed 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -4076,6 +4076,12 @@ static int f2fs_swap_activate(struct swap_info_struct *sis, struct file *file,
if (f2fs_readonly(F2FS_I_SB(inode)->sb))
return -EROFS;
+ if (f2fs_lfs_mode(F2FS_I_SB(inode))) {
+ f2fs_err(F2FS_I_SB(inode),
+ "Swapfile not supported in LFS mode");
+ return -EINVAL;
+ }
+
ret = f2fs_convert_inline_inode(inode);
if (ret)
return ret;
