1 files changed, 126 insertions, 7 deletions

diff --git a/fs/xfs/scrub/nlinks.c b/fs/xfs/scrub/nlinks.c
index 8a7d955789..80aee30886 100644
--- a/fs/xfs/scrub/nlinks.c
+++ b/fs/xfs/scrub/nlinks.c
@@ -18,15 +18,19 @@
 #include "xfs_dir2.h"
 #include "xfs_dir2_priv.h"
 #include "xfs_ag.h"
+#include "xfs_parent.h"
 #include "scrub/scrub.h"
 #include "scrub/common.h"
 #include "scrub/repair.h"
 #include "scrub/xfile.h"
 #include "scrub/xfarray.h"
 #include "scrub/iscan.h"
+#include "scrub/orphanage.h"
 #include "scrub/nlinks.h"
 #include "scrub/trace.h"
 #include "scrub/readdir.h"
+#include "scrub/tempfile.h"
+#include "scrub/listxattr.h"
 
 /*
  * Live Inode Link Count Checking
@@ -43,11 +47,23 @@ int
 xchk_setup_nlinks(
 	struct xfs_scrub	*sc)
 {
+	struct xchk_nlink_ctrs	*xnc;
+	int			error;
+
 	xchk_fsgates_enable(sc, XCHK_FSGATES_DIRENTS);
 
-	sc->buf = kzalloc(sizeof(struct xchk_nlink_ctrs), XCHK_GFP_FLAGS);
-	if (!sc->buf)
+	if (xchk_could_repair(sc)) {
+		error = xrep_setup_nlinks(sc);
+		if (error)
+			return error;
+	}
+
+	xnc = kvzalloc(sizeof(struct xchk_nlink_ctrs), XCHK_GFP_FLAGS);
+	if (!xnc)
 		return -ENOMEM;
+	xnc->xname.name = xnc->namebuf;
+	xnc->sc = sc;
+	sc->buf = xnc;
 
 	return xchk_setup_fs(sc);
 }
@@ -152,6 +168,13 @@ xchk_nlinks_live_update(
 
 	xnc = container_of(nb, struct xchk_nlink_ctrs, dhook.dirent_hook.nb);
 
+	/*
+	 * Ignore temporary directories being used to stage dir repairs, since
+	 * we don't bump the link counts of the children.
+	 */
+	if (xrep_is_tempfile(p->dp))
+		return NOTIFY_DONE;
+
 	trace_xchk_nlinks_live_update(xnc->sc->mp, p->dp, action, p->ip->i_ino,
 			p->delta, p->name->name, p->name->len);
 
@@ -251,12 +274,17 @@ xchk_nlinks_collect_dirent(
 	 * number of parents of the root directory.
 	 *
 	 * Otherwise, increment the number of backrefs pointing back to ino.
+	 *
+	 * If the filesystem has parent pointers, we walk the pptrs to
+	 * determine the backref count.
 	 */
 	if (dotdot) {
 		if (dp == sc->mp->m_rootip)
 			error = xchk_nlinks_update_incore(xnc, ino, 1, 0, 0);
-		else
+		else if (!xfs_has_parent(sc->mp))
 			error = xchk_nlinks_update_incore(xnc, ino, 0, 1, 0);
+		else
+			error = 0;
 		if (error)
 			goto out_unlock;
 	}
@@ -293,6 +321,61 @@ out_incomplete:
 	return error;
 }
 
+/* Bump the backref count for the inode referenced by this parent pointer. */
+STATIC int
+xchk_nlinks_collect_pptr(
+	struct xfs_scrub		*sc,
+	struct xfs_inode		*ip,
+	unsigned int			attr_flags,
+	const unsigned char		*name,
+	unsigned int			namelen,
+	const void			*value,
+	unsigned int			valuelen,
+	void				*priv)
+{
+	struct xfs_name			xname = {
+		.name			= name,
+		.len			= namelen,
+	};
+	struct xchk_nlink_ctrs		*xnc = priv;
+	const struct xfs_parent_rec	*pptr_rec = value;
+	xfs_ino_t			parent_ino;
+	int				error;
+
+	/* Update the shadow link counts if we haven't already failed. */
+
+	if (xchk_iscan_aborted(&xnc->collect_iscan)) {
+		error = -ECANCELED;
+		goto out_incomplete;
+	}
+
+	if (!(attr_flags & XFS_ATTR_PARENT))
+		return 0;
+
+	error = xfs_parent_from_attr(sc->mp, attr_flags, name, namelen, value,
+			valuelen, &parent_ino, NULL);
+	if (error)
+		return error;
+
+	trace_xchk_nlinks_collect_pptr(sc->mp, ip, &xname, pptr_rec);
+
+	mutex_lock(&xnc->lock);
+
+	error = xchk_nlinks_update_incore(xnc, parent_ino, 0, 1, 0);
+	if (error)
+		goto out_unlock;
+
+	mutex_unlock(&xnc->lock);
+	return 0;
+
+out_unlock:
+	mutex_unlock(&xnc->lock);
+	xchk_iscan_abort(&xnc->collect_iscan);
+out_incomplete:
+	xchk_set_incomplete(sc);
+	return error;
+}
+
 /* Walk a directory to bump the observed link counts of the children. */
 STATIC int
 xchk_nlinks_collect_dir(
@@ -303,6 +386,13 @@ xchk_nlinks_collect_dir(
 	unsigned int		lock_mode;
 	int			error = 0;
 
+	/*
+	 * Ignore temporary directories being used to stage dir repairs, since
+	 * we don't bump the link counts of the children.
+	 */
+	if (xrep_is_tempfile(dp))
+		return 0;
+
 	/* Prevent anyone from changing this directory while we walk it. */
 	xfs_ilock(dp, XFS_IOLOCK_SHARED);
 	lock_mode = xfs_ilock_data_map_shared(dp);
@@ -332,6 +422,28 @@ xchk_nlinks_collect_dir(
 	if (error)
 		goto out_abort;
 
+	/* Walk the parent pointers to get real backref counts. */
+	if (xfs_has_parent(sc->mp)) {
+		/*
+		 * If the extended attributes look as though they has been
+		 * zapped by the inode record repair code, we cannot scan for
+		 * parent pointers.
+		 */
+		if (xchk_pptr_looks_zapped(dp)) {
+			error = -EBUSY;
+			goto out_unlock;
+		}
+
+		error = xchk_xattr_walk(sc, dp, xchk_nlinks_collect_pptr, NULL,
+				xnc);
+		if (error == -ECANCELED) {
+			error = 0;
+			goto out_unlock;
+		}
+		if (error)
+			goto out_abort;
+	}
+
 	xchk_iscan_mark_visited(&xnc->collect_iscan, dp);
 	goto out_unlock;
 
@@ -537,6 +649,14 @@ xchk_nlinks_compare_inode(
 	unsigned int		actual_nlink;
 	int			error;
 
+	/*
+	 * Ignore temporary files being used to stage repairs, since we assume
+	 * they're correct for non-directories, and the directory repair code
+	 * doesn't bump the link counts for the children.
+	 */
+	if (xrep_is_tempfile(ip))
+		return 0;
+
 	xfs_ilock(ip, XFS_ILOCK_SHARED);
 	mutex_lock(&xnc->lock);
 
@@ -571,9 +691,11 @@ xchk_nlinks_compare_inode(
 	 * this as a corruption.  The VFS won't let users increase the link
 	 * count, but it will let them decrease it.
 	 */
-	if (total_links > XFS_MAXLINK) {
+	if (total_links > XFS_NLINK_PINNED) {
 		xchk_ino_set_corrupt(sc, ip->i_ino);
 		goto out_corrupt;
+	} else if (total_links > XFS_MAXLINK) {
+		xchk_ino_set_warning(sc, ip->i_ino);
 	}
 
 	/* Link counts should match. */
@@ -850,9 +972,6 @@ xchk_nlinks_setup_scan(
 	xfs_agino_t		first_agino, last_agino;
 	int			error;
 
-	ASSERT(xnc->sc == NULL);
-	xnc->sc = sc;
-
 	mutex_init(&xnc->lock);
 
 	/* Retry iget every tenth of a second for up to 30 seconds. */