From: Mike Snitzer <snitzer@redhat.com>
Date: Thu, 17 Jul 2014 16:32:34 +0000 (-0400)
Subject: dm mpath: cleanup aspects of hannes' patch
X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=8f2abb8bc6301976dda34810f4b155592da09b74;p=linux-dmdedup.git

dm mpath: cleanup aspects of hannes' patch
---

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 494fd8aed7d..50007a7325b 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -514,6 +514,9 @@ static int parse_path_selector(struct dm_arg_set *as, struct priority_group *pg,
 	return 0;
 }
 
+static void __fail_path(struct pgpath *pgpath, struct multipath *m,
+			struct path_selector *ps);
+
 static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps,
 			       struct dm_target *ti)
 {
@@ -567,7 +570,7 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
 	if (p->path.dev)
 		q = bdev_get_queue(p->path.dev->bdev);
 
-	if (q && (m->retain_attached_hw_handler || m->hw_handler_name)) {
+	if (q && m->retain_attached_hw_handler) {
 		attached_handler_name = scsi_dh_attached_handler_name(q, GFP_KERNEL);
 		if (attached_handler_name) {
 			/*
@@ -625,11 +628,9 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
 		goto bad;
 	}
 
-	if (!p->is_active) {
-		ps->type->fail_path(ps, &p->path);
-		p->fail_count++;
-		m->nr_valid_paths--;
-	}
+	if (!p->is_active)
+		__fail_path(p, m, ps);
+
 	return p;
 
  bad:
@@ -946,6 +947,15 @@ static void multipath_dtr(struct dm_target *ti)
 	free_multipath(m);
 }
 
+static void __fail_path(struct pgpath *pgpath, struct multipath *m,
+			struct path_selector *ps)
+{
+	ps->type->fail_path(ps, &pgpath->path);
+	pgpath->fail_count++;
+
+	m->nr_valid_paths--;
+}
+
 /*
  * Take a path out of use.
  */
@@ -961,11 +971,8 @@ static int fail_path(struct pgpath *pgpath)
 
 	DMWARN("Failing path %s.", pgpath->path.pdev);
 
-	pgpath->pg->ps.type->fail_path(&pgpath->pg->ps, &pgpath->path);
 	pgpath->is_active = 0;
-	pgpath->fail_count++;
-
-	m->nr_valid_paths--;
+	__fail_path(pgpath, m, &pgpath->pg->ps);
 
 	if (pgpath == m->current_pgpath)
 		m->current_pgpath = NULL;
@@ -995,12 +1002,6 @@ static int reinstate_path(struct pgpath *pgpath)
 	if (pgpath->is_active)
 		goto out;
 
-	if (!pgpath->path.dev) {
-		DMWARN("Cannot reinstate disabled path %s", pgpath->path.pdev);
-		r = -ENODEV;
-		goto out;
-	}
-
 	if (!pgpath->pg->ps.type->reinstate_path) {
 		DMWARN("Reinstate path not supported by path selector %s",
 		       pgpath->pg->ps.type->name);
@@ -1045,11 +1046,11 @@ static int action_dev(struct multipath *m, struct dm_dev *dev,
 	struct pgpath *pgpath;
 	struct priority_group *pg;
 
-	if (!dev)
-		return 0;
-
 	list_for_each_entry(pg, &m->priority_groups, list) {
 		list_for_each_entry(pgpath, &pg->pgpaths, list) {
+			// FIXME: this will _never_ match a removed failed path
+			// that is now available and attempting to be reinstated
+			// - shouldn't we be able to reinstate a removed failed path?
 			if (pgpath->path.dev == dev)
 				r = action(pgpath);
 		}
@@ -1238,7 +1239,7 @@ static void activate_path(struct work_struct *work)
 	struct pgpath *pgpath =
 		container_of(work, struct pgpath, activate_path.work);
 
-	if (pgpath->path.dev && pgpath->is_active)
+	if (pgpath->is_active && pgpath->path.dev)
 		scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
 				 pg_init_done, pgpath);
 	else