xfs: add online scrub for superblock counters

Teach online scrub how to check the filesystem summary counters. We use the incore delalloc block counter along with the incore AG headers to compute expected values for fdblocks, icount, and ifree, and then check that the percpu counter is within a certain threshold of the expected value. This is done to avoid having to freeze or otherwise lock the filesystem, which means that we're only checking that the counters are fairly close, not that they're exactly correct. Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Dave Chinner <[email protected]> Reviewed-by: Brian Foster <[email protected]>
chewitt · Apr 30, 2019 · 75efa57 · 75efa57
1 parent 9407928
commit 75efa57
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Showing 11 changed files with 461 additions and 3 deletions.
diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
@@ -143,6 +143,7 @@ xfs-y				+= $(addprefix scrub/, \
 				   common.o \
 				   dabtree.o \
 				   dir.o \
+				   fscounters.o \
 				   health.o \
 				   ialloc.o \
 				   inode.o \

diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h
@@ -578,9 +578,10 @@ struct xfs_scrub_metadata {
 #define XFS_SCRUB_TYPE_UQUOTA	21	/* user quotas */
 #define XFS_SCRUB_TYPE_GQUOTA	22	/* group quotas */
 #define XFS_SCRUB_TYPE_PQUOTA	23	/* project quotas */
+#define XFS_SCRUB_TYPE_FSCOUNTERS 24	/* fs summary counters */
 
 /* Number of scrub subcommands. */
-#define XFS_SCRUB_TYPE_NR	24
+#define XFS_SCRUB_TYPE_NR	25
 
 /* i: Repair this metadata. */
 #define XFS_SCRUB_IFLAG_REPAIR		(1 << 0)

diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c
@@ -185,7 +185,7 @@ xfs_verify_rtbno(
 }
 
 /* Calculate the range of valid icount values. */
-static void
+void
 xfs_icount_range(
 	struct xfs_mount	*mp,
 	unsigned long long	*min,

diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h
@@ -191,5 +191,7 @@ bool xfs_verify_dir_ino(struct xfs_mount *mp, xfs_ino_t ino);
 bool xfs_verify_rtbno(struct xfs_mount *mp, xfs_rtblock_t rtbno);
 bool xfs_verify_icount(struct xfs_mount *mp, unsigned long long icount);
 bool xfs_verify_dablk(struct xfs_mount *mp, xfs_fileoff_t off);
+void xfs_icount_range(struct xfs_mount *mp, unsigned long long *min,
+		unsigned long long *max);
 
 #endif	/* __XFS_TYPES_H__ */
diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
@@ -209,6 +209,15 @@ xchk_ino_set_preen(
 	trace_xchk_ino_preen(sc, ino, __return_address);
 }
 
+/* Record something being wrong with the filesystem primary superblock. */
+void
+xchk_set_corrupt(
+	struct xfs_scrub	*sc)
+{
+	sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
+	trace_xchk_fs_error(sc, 0, __return_address);
+}
+
 /* Record a corrupt block. */
 void
 xchk_block_set_corrupt(

diff --git a/fs/xfs/scrub/common.h b/fs/xfs/scrub/common.h
@@ -39,6 +39,7 @@ void xchk_block_set_preen(struct xfs_scrub *sc,
 		struct xfs_buf *bp);
 void xchk_ino_set_preen(struct xfs_scrub *sc, xfs_ino_t ino);
 
+void xchk_set_corrupt(struct xfs_scrub *sc);
 void xchk_block_set_corrupt(struct xfs_scrub *sc,
 		struct xfs_buf *bp);
 void xchk_ino_set_corrupt(struct xfs_scrub *sc, xfs_ino_t ino);
@@ -105,6 +106,7 @@ xchk_setup_quota(struct xfs_scrub *sc, struct xfs_inode *ip)
 	return -ENOENT;
 }
 #endif
+int xchk_setup_fscounters(struct xfs_scrub *sc, struct xfs_inode *ip);
 
 void xchk_ag_free(struct xfs_scrub *sc, struct xchk_ag *sa);
 int xchk_ag_init(struct xfs_scrub *sc, xfs_agnumber_t agno,