xfs: scrub metadata directories

Teach online scrub about the metadata directory tree.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

4 files changed, 52 insertions, 2 deletions

diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
index 3811f21b7697..acca10a72fc1 100644
--- a/fs/xfs/scrub/dir.c
+++ b/fs/xfs/scrub/dir.c
@@ -134,6 +134,15 @@ xchk_dir_check_ftype(
 			xfs_mode_to_ftype(VFS_I(ip)->i_mode));
 	if (ino_dtype != dtype)
 		xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset);
+
+	/*
+	 * Metadata and regular inodes cannot cross trees.  This property
+	 * cannot change without a full inode free and realloc cycle, so it's
+	 * safe to check this without holding locks.
+	 */
+	if (xfs_is_metadata_inode(ip) ^ xfs_is_metadata_inode(sdc->sc->ip))
+		xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, 0);
+
 	xfs_irele(ip);
 out:
 	return error;
diff --git a/fs/xfs/scrub/dir_repair.c b/fs/xfs/scrub/dir_repair.c
index 8f069636ae1a..91d812dbdb1d 100644
--- a/fs/xfs/scrub/dir_repair.c
+++ b/fs/xfs/scrub/dir_repair.c
@@ -180,6 +180,12 @@ xrep_dir_salvage_entry(
 	if (error)
 		return 0;
 
+	/* Don't mix metadata and regular directory trees. */
+	if (xfs_is_metadata_inode(ip) ^ xfs_is_metadata_inode(rd->sc->ip)) {
+		xfs_irele(ip);
+		return 0;
+	}
+
 	key.ftype = xfs_mode_to_ftype(VFS_I(ip)->i_mode);
 	xfs_irele(ip);
 
diff --git a/fs/xfs/scrub/parent.c b/fs/xfs/scrub/parent.c
index 02c682be29de..519acb248d97 100644
--- a/fs/xfs/scrub/parent.c
+++ b/fs/xfs/scrub/parent.c
@@ -221,6 +221,16 @@ xchk_parent_validate(
 	}
 
 	/*
+	 * Metadata and regular inodes cannot cross trees.  This property
+	 * cannot change without a full inode free and realloc cycle, so it's
+	 * safe to check this without holding locks.
+	 */
+	if (xfs_is_metadata_inode(dp) ^ xfs_is_metadata_inode(sc->ip)) {
+		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+		goto out_rele;
+	}
+
+	/*
 	 * We prefer to keep the inode locked while we lock and search
 	 * its alleged parent for a forward reference.  If we can grab
 	 * the iolock, validate the pointers and we're done.  We must
@@ -348,6 +358,14 @@ xchk_parent(
 		goto out;
 	}
 
+	/* Is this the metadata root dir?  Then '..' must point to itself. */
+	if (sc->ip == mp->m_metadirip) {
+		if (sc->ip->i_ino != mp->m_sb.sb_metadirino ||
+		    sc->ip->i_ino != dnum)
+			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+		goto out;
+	}
+
 	do {
 		error = xchk_parent_validate(sc, dnum, &try_again);
 		if (error)
diff --git a/fs/xfs/scrub/parent_repair.c b/fs/xfs/scrub/parent_repair.c
index 75e0db34b3b3..4570e7c94c32 100644
--- a/fs/xfs/scrub/parent_repair.c
+++ b/fs/xfs/scrub/parent_repair.c
@@ -129,6 +129,10 @@ findparent_walk_directory(
 	if (!S_ISDIR(VFS_I(dp)->i_mode))
 		goto out_rele;
 
+	/* Don't mix metadata and regular directory trees. */
+	if (xfs_is_metadata_inode(dp) ^ xfs_is_metadata_inode(fpi->sc->ip))
+		goto out_rele;
+
 	/*
 	 * Try to get the parent directory's IOLOCK.  We still hold the child's
 	 * IOLOCK in exclusive mode, so we must avoid an ABBA deadlock.
@@ -304,14 +308,27 @@ xrep_findparent(
 	}
 
 	/*
+	 * If we are the metadata root directory, then we are our own parent.
+	 * Return the root directory.
+	 */
+	if (sc->ip == sc->mp->m_metadirip) {
+		*parent_ino = sc->mp->m_sb.sb_metadirino;
+		return 0;
+	}
+
+	/*
 	 * If we are an unlinked directory, the parent won't have a link to us.
 	 * We might as well return the suggestion, or the root directory if the
 	 * suggestion is NULLFSINO or garbage.  There's no point in scanning
 	 * the filesystem.
 	 */
 	if (VFS_I(sc->ip)->i_nlink == 0) {
-		if (!xfs_verify_dir_ino(sc->mp, *parent_ino))
-			*parent_ino = sc->mp->m_sb.sb_rootino;
+		if (!xfs_verify_dir_ino(sc->mp, *parent_ino)) {
+			if (xfs_is_metadata_inode(sc->ip))
+				*parent_ino = sc->mp->m_sb.sb_metadirino;
+			else
+				*parent_ino = sc->mp->m_sb.sb_rootino;
+		}
 		return 0;
 	}