Add reinstate_path function (unused).
--- diff/drivers/md/dm-mpath.c	2004-09-28 16:15:18.000000000 +0100
+++ source/drivers/md/dm-mpath.c	2004-09-28 16:18:11.000000000 +0100
@@ -514,6 +514,34 @@
 	spin_unlock_irqrestore(&path->failed_lock, flags);
 }
 
+static int reinstate_path(struct path *path)
+{
+	int r = 0;
+	unsigned long flags;
+	struct multipath *m;
+
+	spin_lock_irqsave(&path->failed_lock, flags);
+
+	if (path->is_active)
+		goto out;
+
+	r = path->pg->ps.type->reinstate_path(&path->pg->ps, path);
+	if (r)
+		goto out;
+
+	path->is_active = 1;
+	m = path->pg->m;
+
+	spin_lock(&m->lock);
+	m->nr_valid_paths++;
+	spin_unlock(&m->lock);
+
+out:
+	spin_unlock_irqrestore(&path->failed_lock, flags);
+
+	return r;
+}
+
 static int do_end_io(struct multipath *m, struct bio *bio,
 		     int error, struct mpath_io *mpio)
 {
--- diff/drivers/md/dm-path-selector.c	2004-09-28 16:15:18.000000000 +0100
+++ source/drivers/md/dm-path-selector.c	2004-09-28 16:18:11.000000000 +0100
@@ -272,6 +272,34 @@
 	spin_unlock_irqrestore(&s->lock, flags);
 }
 
+static int rr_reinstate_path(struct path_selector *ps, struct path *p)
+{
+	int r = 0;
+	unsigned long flags;
+	struct selector *s = (struct selector *) ps->context;
+	struct path_info *pi;
+
+	/*
+	 * This function will be called infrequently so we don't
+	 * mind the expense of these searches.
+	 */
+	spin_lock_irqsave(&s->lock, flags);
+	pi = path_lookup(&s->invalid_paths, p);
+	if (!pi)
+		pi = path_lookup(&s->valid_paths, p);
+
+	if (pi)
+		list_move(&pi->list, &s->valid_paths);
+	else {
+		DMWARN("asked to change the state of an unknown path");
+		r = -EINVAL;
+	}
+
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	return r;
+}
+
 /* Path selector */
 static struct path *rr_select_path(struct path_selector *ps,
 				   unsigned *repeat_count)
@@ -307,6 +335,7 @@
 	.dtr = rr_dtr,
 	.add_path = rr_add_path,
 	.fail_path = rr_fail_path,
+	.reinstate_path = rr_reinstate_path,
 	.select_path = rr_select_path,
 	.status = rr_status,
 };
--- diff/drivers/md/dm-path-selector.h	2004-09-28 16:15:18.000000000 +0100
+++ source/drivers/md/dm-path-selector.h	2004-09-28 16:18:11.000000000 +0100
@@ -63,6 +63,12 @@
 				 struct path *p);
 
 /*
+ * Ask selector to reinstate a path.
+ */
+typedef	int (*ps_reinstate_path_fn) (struct path_selector *ps,
+				     struct path *p);
+
+/*
  * Table content based on parameters added in ps_add_path_fn
  * or path selector status
  */
@@ -83,6 +89,7 @@
 
 	ps_add_path_fn add_path;
 	ps_fail_path_fn fail_path;
+	ps_reinstate_path_fn reinstate_path;
 	ps_select_path_fn select_path;
 	ps_status_fn status;
 };