This patch introduces a rocompat feature flag to signal the presence of checksums for metadata blocks. It also provides storage for a precomputed UUID checksum. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> --- fs/ext4/ext4.h | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index b7d7bd0..8ee8646 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1222,6 +1222,9 @@ struct ext4_sb_info { /* record the last minlen when FITRIM is called. */ atomic_t s_last_trim_minblks; + + /* Precomputed FS UUID checksum */ + __u32 s_uuid_crc; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) @@ -1360,6 +1363,7 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei) #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100 +#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002 @@ -1402,7 +1406,8 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei) EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \ EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \ EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\ - EXT4_FEATURE_RO_COMPAT_HUGE_FILE) + EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\ + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) /* * Default values for user and/or group using reserved blocks -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html