xfs: wrap ilock/iunlock operations on sc->ip

Scrub tracks the resources that it's holding onto in the xfs_scrub
structure.  This includes the inode being checked (if applicable) and
the inode lock state of that inode.  Replace the open-coded structure
manipulation with a trivial helper to eliminate sources of error.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

1 files changed, 33 insertions, 5 deletions

diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
index 6354cb45310f..82d2a85d6461 100644
--- a/fs/xfs/scrub/common.c
+++ b/fs/xfs/scrub/common.c
@@ -1022,20 +1022,48 @@ xchk_setup_inode_contents(
 		return error;
 
 	/* Lock the inode so the VFS cannot touch this file. */
-	sc->ilock_flags = XFS_IOLOCK_EXCL;
-	xfs_ilock(sc->ip, sc->ilock_flags);
+	xchk_ilock(sc, XFS_IOLOCK_EXCL);
 
 	error = xchk_trans_alloc(sc, resblks);
 	if (error)
 		goto out;
-	sc->ilock_flags |= XFS_ILOCK_EXCL;
-	xfs_ilock(sc->ip, XFS_ILOCK_EXCL);
-
+	xchk_ilock(sc, XFS_ILOCK_EXCL);
 out:
 	/* scrub teardown will unlock and release the inode for us */
 	return error;
 }
 
+void
+xchk_ilock(
+	struct xfs_scrub	*sc,
+	unsigned int		ilock_flags)
+{
+	xfs_ilock(sc->ip, ilock_flags);
+	sc->ilock_flags |= ilock_flags;
+}
+
+bool
+xchk_ilock_nowait(
+	struct xfs_scrub	*sc,
+	unsigned int		ilock_flags)
+{
+	if (xfs_ilock_nowait(sc->ip, ilock_flags)) {
+		sc->ilock_flags |= ilock_flags;
+		return true;
+	}
+
+	return false;
+}
+
+void
+xchk_iunlock(
+	struct xfs_scrub	*sc,
+	unsigned int		ilock_flags)
+{
+	sc->ilock_flags &= ~ilock_flags;
+	xfs_iunlock(sc->ip, ilock_flags);
+}
+
 /*
  * Predicate that decides if we need to evaluate the cross-reference check.
  * If there was an error accessing the cross-reference btree, just delete