ext4: Replace open coded mdata csum feature to helper function
Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized csum machinery.
#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END
# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)
https://bugzilla.kernel.org/show_bug.cgi?id=82201
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c
index 32bce84..8313ca3 100644
--- a/fs/ext4/mmp.c
+++ b/fs/ext4/mmp.c
@@ -20,8 +20,7 @@
static int ext4_mmp_csum_verify(struct super_block *sb, struct mmp_struct *mmp)
{
- if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
- EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ if (!ext4_has_metadata_csum(sb))
return 1;
return mmp->mmp_checksum == ext4_mmp_csum(sb, mmp);
@@ -29,8 +28,7 @@
static void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp)
{
- if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
- EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ if (!ext4_has_metadata_csum(sb))
return;
mmp->mmp_checksum = ext4_mmp_csum(sb, mmp);