From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Benjamin Marzinski <bmarzins@redhat.com>
Date: Wed, 15 Oct 2014 10:39:30 -0500
Subject: [PATCH] RH: don't start without a config file

If /etc/multipath.conf doesn't exist, don't start multipathd and blacklist
all devices when running multipath.  A completely blank configuration file
is almost never what users want.  Also, people may have the multipath
packages installed but don't want to use them.  This patch provides a
simple way to disable multipath.  Simply removing or renaming
/etc/multipath.conf will keep multipath from doing anything.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
---
 libmultipath/config.c         | 15 +++++++++++++++
 libmultipath/config.h         |  1 +
 multipath/multipath.rules     |  1 +
 multipathd/multipathd.8       |  2 ++
 multipathd/multipathd.service |  1 +
 5 files changed, 20 insertions(+)

diff --git a/libmultipath/config.c b/libmultipath/config.c
index 5872927..0607403 100644
--- a/libmultipath/config.c
+++ b/libmultipath/config.c
@@ -26,6 +26,7 @@
 #include "devmapper.h"
 #include "mpath_cmd.h"
 #include "propsel.h"
+#include "version.h"
 
 static int
 hwe_strmatch (struct hwentry *hwe1, struct hwentry *hwe2)
@@ -658,6 +659,20 @@ load_config (char * file)
 			factorize_hwtable(conf->hwtable, builtin_hwtable_size);
 		}
 
+	} else {
+		condlog(0, "/etc/multipath.conf does not exist, blacklisting all devices.");
+		if (conf->blist_devnode == NULL) {
+			conf->blist_devnode = vector_alloc();
+			if (!conf->blist_devnode) {
+				condlog(0, "cannot allocate blacklist\n");
+				goto out;
+			}
+		}
+		if (store_ble(conf->blist_devnode, strdup(".*"),
+		              ORIGIN_NO_CONFIG)) {
+			condlog(0, "cannot store default no-config blacklist\n");
+			goto out;
+		}
 	}
 
 	conf->processed_main_config = 1;
diff --git a/libmultipath/config.h b/libmultipath/config.h
index fcbe3fc..3a42435 100644
--- a/libmultipath/config.h
+++ b/libmultipath/config.h
@@ -9,6 +9,7 @@
 
 #define ORIGIN_DEFAULT 0
 #define ORIGIN_CONFIG  1
+#define ORIGIN_NO_CONFIG 2
 
 /*
  * In kernel, fast_io_fail == 0 means immediate failure on rport delete.
diff --git a/multipath/multipath.rules b/multipath/multipath.rules
index d658073..b3f54d7 100644
--- a/multipath/multipath.rules
+++ b/multipath/multipath.rules
@@ -9,6 +9,7 @@ IMPORT{cmdline}="nompath"
 ENV{nompath}=="?*", GOTO="end_mpath"
 IMPORT{cmdline}="multipath"
 ENV{multipath}=="off", GOTO="end_mpath"
+TEST!="/etc/multipath.conf", GOTO="end_mpath"
 
 ENV{DEVTYPE}!="partition", GOTO="test_dev"
 IMPORT{parent}="DM_MULTIPATH_DEVICE_PATH"
diff --git a/multipathd/multipathd.8 b/multipathd/multipathd.8
index e78ac9e..09cdead 100644
--- a/multipathd/multipathd.8
+++ b/multipathd/multipathd.8
@@ -38,6 +38,8 @@ map regains its maximum performance and redundancy.
 This daemon executes the external \fBmultipath\fR tool when events occur.
 In turn, the multipath tool signals the multipathd daemon when it is done with
 devmap reconfiguration, so that it can refresh its failed path list.
+
+In this Linux distribution, multipathd does not run unless a /etc/multipath.conf file exists.
 .
 .
 .\" ----------------------------------------------------------------------------
diff --git a/multipathd/multipathd.service b/multipathd/multipathd.service
index ba24983..17434ce 100644
--- a/multipathd/multipathd.service
+++ b/multipathd/multipathd.service
@@ -4,6 +4,7 @@ Wants=systemd-udev-trigger.service systemd-udev-settle.service
 Before=iscsi.service iscsid.service lvm2-activation-early.service
 Before=local-fs-pre.target blk-availability.service
 After=multipathd.socket systemd-udev-trigger.service systemd-udev-settle.service
+ConditionPathExists=/etc/multipath.conf
 DefaultDependencies=no
 Conflicts=shutdown.target
 ConditionKernelCommandLine=!nompath
-- 
2.7.4