[PATCH 08/39] xfs: create an ioctl to scrub AG metadata

["Darrick J. Wong" <darrick.wong@oracle.com>]

Create an ioctl that can be used to scrub internal filesystem metadata.
The new ioctl takes the metadata type, an (optional) AG number, an
(optional) inode number and generation, and a flags argument.  This will
be used by the upcoming XFS online scrub tool.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 libxfs/xfs_fs.h |   36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)


diff --git a/libxfs/xfs_fs.h b/libxfs/xfs_fs.h
index 6857355..27878cf 100644
--- a/libxfs/xfs_fs.h
+++ b/libxfs/xfs_fs.h
@@ -578,6 +578,40 @@ typedef struct xfs_swapext
 #define XFS_FSOP_GOING_FLAGS_LOGFLUSH		0x1	/* flush log but not data */
 #define XFS_FSOP_GOING_FLAGS_NOLOGFLUSH		0x2	/* don't flush log nor data */
 
+/* metadata scrubbing */
+struct xfs_scrub_metadata {
+	__u32 sm_type;		/* What to check? */
+	__u32 sm_flags;		/* Flags; none defined right now. */
+	union {
+		__u32		__agno;
+		struct {
+			__u64	__ino;
+			__u32	__gen;
+		} i;
+		__u64		__reserved[7];	/* pad to 64 bytes */
+	} p;
+};
+#define sm_agno	p.__agno
+#define sm_ino	p.i.__ino
+#define sm_gen	p.i.__gen
+
+/*
+ * Metadata types and flags for scrub operation.
+ */
+#define XFS_SCRUB_TYPE_TEST	0	/* dummy to test ioctl */
+#define XFS_SCRUB_TYPE_MAX	0
+
+#define XFS_SCRUB_FLAG_REPAIR	0x1	/* i: repair this metadata */
+#define XFS_SCRUB_FLAG_CORRUPT	0x2	/* o: needs repair */
+#define XFS_SCRUB_FLAG_PREEN	0x4	/* o: could be optimized */
+#define XFS_SCRUB_FLAG_XREF_FAIL 0x8	/* o: errors during cross-referencing */
+
+#define XFS_SCRUB_FLAGS_IN	(XFS_SCRUB_FLAG_REPAIR)
+#define XFS_SCRUB_FLAGS_OUT	(XFS_SCRUB_FLAG_CORRUPT | \
+				 XFS_SCRUB_FLAG_PREEN | \
+				 XFS_SCRUB_FLAG_XREF_FAIL)
+#define XFS_SCRUB_FLAGS_ALL	(XFS_SCRUB_FLAGS_IN | XFS_SCRUB_FLAGS_OUT)
+
 /*
  * ioctl limits
  */
@@ -587,6 +621,7 @@ typedef struct xfs_swapext
 #  define XFS_XATTR_LIST_MAX 65536
 #endif
 
+
 /*
  * ioctl commands that are used by Linux filesystems
  */
@@ -618,6 +653,7 @@ typedef struct xfs_swapext
 #define XFS_IOC_ZERO_RANGE	_IOW ('X', 57, struct xfs_flock64)
 #define XFS_IOC_FREE_EOFBLOCKS	_IOR ('X', 58, struct xfs_fs_eofblocks)
 #define XFS_IOC_GETFSMAP	_IOWR('X', 59, struct fsmap_head)
+#define XFS_IOC_SCRUB_METADATA	_IOWR('X', 60, struct xfs_scrub_metadata)
 
 /*
  * ioctl commands that replace IRIX syssgi()'s