device-mapper-multipath/0035-RHBZ-467709-add-followover.patch

---
 libmultipath/dict.c    |   12 ++++++++++++
 libmultipath/print.c   |    2 ++
 libmultipath/structs.h |    3 ++-
 multipathd/main.c      |   31 +++++++++++++++++++++++++++++--
 4 files changed, 45 insertions(+), 3 deletions(-)

Index: multipath-tools/libmultipath/dict.c
===================================================================
--- multipath-tools.orig/libmultipath/dict.c
+++ multipath-tools/libmultipath/dict.c
@@ -348,6 +348,8 @@ default_failback_handler(vector strvec)
 		conf->pgfailback = -FAILBACK_MANUAL;
 	else if (strlen(buff) == 9 && !strcmp(buff, "immediate"))
 		conf->pgfailback = -FAILBACK_IMMEDIATE;
+	else if (strlen(buff) == 10 && !strcmp(buff, "followover"))
+		conf->pgfailback = -FAILBACK_FOLLOWOVER;
 	else
 		conf->pgfailback = atoi(buff);
 
@@ -917,6 +919,8 @@ hw_failback_handler(vector strvec)
 		hwe->pgfailback = -FAILBACK_MANUAL;
 	else if (strlen(buff) == 9 && !strcmp(buff, "immediate"))
 		hwe->pgfailback = -FAILBACK_IMMEDIATE;
+	else if (strlen(buff) == 10 && !strcmp(buff, "followover"))
+		hwe->pgfailback = -FAILBACK_FOLLOWOVER;
 	else
 		hwe->pgfailback = atoi(buff);
 
@@ -1169,6 +1173,8 @@ mp_failback_handler(vector strvec)
 		mpe->pgfailback = -FAILBACK_MANUAL;
 	else if (strlen(buff) == 9 && !strcmp(buff, "immediate"))
 		mpe->pgfailback = -FAILBACK_IMMEDIATE;
+	else if (strlen(buff) == 10 && !strcmp(buff, "followover"))
+		mpe->pgfailback = -FAILBACK_FOLLOWOVER;
 	else
 		mpe->pgfailback = atoi(buff);
 
@@ -1472,6 +1478,8 @@ snprint_mp_failback (char * buff, int le
 		return snprintf(buff, len, "manual");
 	case -FAILBACK_IMMEDIATE:
 		return snprintf(buff, len, "immediate");
+	case -FAILBACK_FOLLOWOVER:
+		return snprintf(buff, len, "followover");
 	default:
 		return snprintf(buff, len, "%i", mpe->pgfailback);
 	}
@@ -1748,6 +1756,8 @@ snprint_hw_failback (char * buff, int le
 		return snprintf(buff, len, "manual");
 	case -FAILBACK_IMMEDIATE:
 		return snprintf(buff, len, "immediate");
+	case -FAILBACK_FOLLOWOVER:
+		return snprintf(buff, len, "followover");
 	default:
 		return snprintf(buff, len, "%i", hwe->pgfailback);
 	}
@@ -1970,6 +1980,8 @@ snprint_def_failback (char * buff, int l
 		return snprintf(buff, len, "manual");
 	case -FAILBACK_IMMEDIATE:
 		return snprintf(buff, len, "immediate");
+	case -FAILBACK_FOLLOWOVER:
+		return snprintf(buff, len, "followover");
 	default:
 		return snprintf(buff, len, "%i", pgfailback);
 	}
Index: multipath-tools/libmultipath/print.c
===================================================================
--- multipath-tools.orig/libmultipath/print.c
+++ multipath-tools/libmultipath/print.c
@@ -142,6 +142,8 @@ snprint_failback (char * buff, size_t le
 {
 	if (mpp->pgfailback == -FAILBACK_IMMEDIATE)
 		return snprintf(buff, len, "immediate");
+	if (mpp->pgfailback == -FAILBACK_FOLLOWOVER)
+		return snprintf(buff, len, "followover");
 
 	if (!mpp->failback_tick)
 		return snprintf(buff, len, "-");
Index: multipath-tools/libmultipath/structs.h
===================================================================
--- multipath-tools.orig/libmultipath/structs.h
+++ multipath-tools/libmultipath/structs.h
@@ -39,7 +39,8 @@ enum rr_weight_mode {
 enum failback_mode {
 	FAILBACK_UNDEF,
 	FAILBACK_MANUAL,
-	FAILBACK_IMMEDIATE
+	FAILBACK_IMMEDIATE,
+	FAILBACK_FOLLOWOVER
 };
 
 enum sysfs_buses {
Index: multipath-tools/multipathd/main.c
===================================================================
--- multipath-tools.orig/multipathd/main.c
+++ multipath-tools/multipathd/main.c
@@ -875,6 +875,32 @@ mpvec_garbage_collector (struct vectors 
 	}
 }
 
+/* This is called after a path has started working again. It the multipath
+ * device for this path uses the followover failback type, and this is the
+ * best pathgroup, and this is the first path in the pathgroup to come back
+ * up, then switch to this pathgroup */
+static int
+followover_should_failback(struct path * pp)
+{
+	struct pathgroup * pgp;
+	struct path *pp1;
+	int i;
+
+	if (pp->mpp->pgfailback != -FAILBACK_FOLLOWOVER ||
+	    !pp->mpp->pg || !pp->pgindex ||
+	    pp->pgindex != pp->mpp->bestpg)
+		return 0;
+
+	pgp = VECTOR_SLOT(pp->mpp->pg, pp->pgindex - 1);
+	vector_foreach_slot(pgp->paths, pp1, i) {
+		if (pp1 == pp)
+			continue;
+		if (pp1->state != PATH_DOWN && pp1->state != PATH_SHAKY)
+			return 0;
+	}
+	return 1;
+}
+
 static void
 defered_failback_tick (vector mpvec)
 {
@@ -1013,8 +1039,9 @@ check_path (struct vectors * vecs, struc
 		if (pp->mpp->pgfailback > 0)
 			pp->mpp->failback_tick =
 				pp->mpp->pgfailback + 1;
-		else if (pp->mpp->pgfailback == -FAILBACK_IMMEDIATE &&
-		    need_switch_pathgroup(pp->mpp, 1))
+		else if (need_switch_pathgroup(pp->mpp, 1) &&
+			 (pp->mpp->pgfailback == -FAILBACK_IMMEDIATE ||
+			  followover_should_failback(pp)))
 			switch_pathgroup(pp->mpp);
 
 		/*