From: "Darrick J. Wong" Subject: [PATCH 07/28] ext4: Create a rocompat flag for extended metadata checksumming Date: Sat, 08 Oct 2011 00:54:29 -0700 Message-ID: <20111008075429.20506.95505.stgit@elm3c44.beaverton.ibm.com> References: <20111008075343.20506.23155.stgit@elm3c44.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Sunil Mushran , Martin K Petersen , Greg Freemyer , Amir Goldstein , linux-kernel , Andi Kleen , Mingming Cao , Joel Becker , linux-fsdevel , linux-ext4@vger.kernel.org, Coly Li To: Andreas Dilger , Theodore Tso , "Darrick J. Wong" Return-path: In-Reply-To: <20111008075343.20506.23155.stgit@elm3c44.beaverton.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org 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 --- 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