xfs: add a per-leaf block callback to xchk_xattr_walk

Add a second callback function to xchk_xattr_walk so that we can do
something in between attr leaf blocks.  This will be used by the next
patch to see if we should flush cached parent pointer updates to
constrain memory usage.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/scrub/attr.c

@@ -675,7 +675,7 @@ xchk_xattr(
 	 * iteration, which doesn't really follow the usual buffer
 	 * locking order.
 	 */
-	error = xchk_xattr_walk(sc, sc->ip, xchk_xattr_actor, NULL);
+	error = xchk_xattr_walk(sc, sc->ip, xchk_xattr_actor, NULL, NULL);
 	if (!xchk_fblock_process_error(sc, XFS_ATTR_FORK, 0, &error))
 		return error;
 

fs/xfs/scrub/dir_repair.c

@@ -1288,7 +1288,7 @@ xrep_dir_scan_file(
 		goto scan_done;
 	}
 
-	error = xchk_xattr_walk(rd->sc, ip, xrep_dir_scan_pptr, rd);
+	error = xchk_xattr_walk(rd->sc, ip, xrep_dir_scan_pptr, NULL, rd);
 	if (error)
 		goto scan_done;
 

fs/xfs/scrub/listxattr.c

@@ -221,6 +221,7 @@ xchk_xattr_walk_node(
 	struct xfs_scrub		*sc,
 	struct xfs_inode		*ip,
 	xchk_xattr_fn			attr_fn,
+	xchk_xattrleaf_fn		leaf_fn,
 	void				*priv)
 {
 	struct xfs_attr3_icleaf_hdr	leafhdr;
@@ -252,6 +253,12 @@ xchk_xattr_walk_node(
 
 		xfs_trans_brelse(sc->tp, leaf_bp);
 
+		if (leaf_fn) {
+			error = leaf_fn(sc, priv);
+			if (error)
+				goto out_bitmap;
+		}
+
 		/* Make sure we haven't seen this new leaf already. */
 		len = 1;
 		if (xdab_bitmap_test(&seen_dablks, leafhdr.forw, &len)) {
@@ -288,6 +295,7 @@ xchk_xattr_walk(
 	struct xfs_scrub	*sc,
 	struct xfs_inode	*ip,
 	xchk_xattr_fn		attr_fn,
+	xchk_xattrleaf_fn	leaf_fn,
 	void			*priv)
 {
 	int			error;
@@ -308,5 +316,5 @@ xchk_xattr_walk(
 	if (xfs_attr_is_leaf(ip))
 		return xchk_xattr_walk_leaf(sc, ip, attr_fn, priv);
 
-	return xchk_xattr_walk_node(sc, ip, attr_fn, priv);
+	return xchk_xattr_walk_node(sc, ip, attr_fn, leaf_fn, priv);
 }

fs/xfs/scrub/listxattr.h

@@ -11,7 +11,9 @@ typedef int (*xchk_xattr_fn)(struct xfs_scrub *sc, struct xfs_inode *ip,
 		unsigned int namelen, const void *value, unsigned int valuelen,
 		void *priv);
 
+typedef int (*xchk_xattrleaf_fn)(struct xfs_scrub *sc, void *priv);
+
 int xchk_xattr_walk(struct xfs_scrub *sc, struct xfs_inode *ip,
-		xchk_xattr_fn attr_fn, void *priv);
+		xchk_xattr_fn attr_fn, xchk_xattrleaf_fn leaf_fn, void *priv);
 
 #endif /* __XFS_SCRUB_LISTXATTR_H__ */

fs/xfs/scrub/nlinks.c

@@ -434,7 +434,8 @@ xchk_nlinks_collect_dir(
 			goto out_unlock;
 		}
 
-		error = xchk_xattr_walk(sc, dp, xchk_nlinks_collect_pptr, xnc);
+		error = xchk_xattr_walk(sc, dp, xchk_nlinks_collect_pptr, NULL,
+				xnc);
 		if (error == -ECANCELED) {
 			error = 0;
 			goto out_unlock;

fs/xfs/scrub/parent.c

@@ -317,7 +317,7 @@ xchk_parent_pptr_and_dotdot(
 		return 0;
 
 	/* Otherwise, walk the pptrs again, and check. */
-	error = xchk_xattr_walk(sc, sc->ip, xchk_parent_scan_dotdot, pp);
+	error = xchk_xattr_walk(sc, sc->ip, xchk_parent_scan_dotdot, NULL, pp);
 	if (error == -ECANCELED) {
 		/* Found a parent pointer that matches dotdot. */
 		return 0;
@@ -699,7 +699,8 @@ xchk_parent_count_pptrs(
 	 */
 	if (pp->need_revalidate) {
 		pp->pptrs_found = 0;
-		error = xchk_xattr_walk(sc, sc->ip, xchk_parent_count_pptr, pp);
+		error = xchk_xattr_walk(sc, sc->ip, xchk_parent_count_pptr,
+				NULL, pp);
 		if (error == -EFSCORRUPTED) {
 			/* Found a bad parent pointer */
 			xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
@@ -758,7 +759,7 @@ xchk_parent_pptr(
 	if (error)
 		goto out_entries;
 
-	error = xchk_xattr_walk(sc, sc->ip, xchk_parent_scan_attr, pp);
+	error = xchk_xattr_walk(sc, sc->ip, xchk_parent_scan_attr, NULL, pp);
 	if (error == -ECANCELED) {
 		error = 0;
 		goto out_names;