xfs: add CRC infrastructure
- add a mount feature bit for CRC enabled filesystems
- add some helpers for generating and verifying the CRCs
- add a copy_uuid helper
The checksumming helpers are loosely based on similar ones in sctp,
all other bits come from Dave Chinner.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
diff --git a/fs/xfs/xfs_sb.h b/fs/xfs/xfs_sb.h
index f429d9d..a05b451 100644
--- a/fs/xfs/xfs_sb.h
+++ b/fs/xfs/xfs_sb.h
@@ -81,6 +81,7 @@
#define XFS_SB_VERSION2_ATTR2BIT 0x00000008 /* Inline attr rework */
#define XFS_SB_VERSION2_PARENTBIT 0x00000010 /* parent pointers */
#define XFS_SB_VERSION2_PROJID32BIT 0x00000080 /* 32 bit project id */
+#define XFS_SB_VERSION2_CRCBIT 0x00000100 /* metadata CRCs */
#define XFS_SB_VERSION2_OKREALFBITS \
(XFS_SB_VERSION2_LAZYSBCOUNTBIT | \
@@ -503,6 +504,12 @@
(sbp->sb_features2 & XFS_SB_VERSION2_PROJID32BIT);
}
+static inline int xfs_sb_version_hascrc(xfs_sb_t *sbp)
+{
+ return (xfs_sb_version_hasmorebits(sbp) &&
+ (sbp->sb_features2 & XFS_SB_VERSION2_CRCBIT));
+}
+
/*
* end of superblock version macros
*/