lvm2: fix start lvm2-monitor.service failed

While systemd based, start lvm2-monitor.service failed.
...
|Sep 21 05:37:34 qemux86-64 lvm[389]:   /var/lock: stat failed: No such
file or directory
|Sep 21 05:37:34 qemux86-64 systemd[1]: lvm2-monitor.service: Main
process exited, code=exited, status=5/NOTINSTALLED
...
The failure of lvm2-monitor.service caused reboot hung when disk
partion is lvm thin provision.

While starting lvm2-monitor.service, it reqires the existence of
locking dir "/var/lock" which is a symlink to "../run/lock" in oe-core,
and "/run" is created in "/etc/fstab" which have to be be after the
start of lvm2-monitor.service.

So tweak the locking dir to "/tmp/lock" and make sure the dir existence
(after tmp.mount).

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

meta-oe/recipes-support/lvm2/files/0006-start-lvm2-monitor.service-after-tmp.mount.patch

@@ -0,0 +1,32 @@
+From 24a2c47fd01dde1710f1fa66f5c30ce7010c5956 Mon Sep 17 00:00:00 2001
+From: Hongxu Jia <hongxu.jia@windriver.com>
+Date: Thu, 21 Sep 2017 15:28:10 +0800
+Subject: [PATCH] start lvm2-monitor.service after tmp.mount
+
+The lvm2-monitor.service reqires the existence of locking_dir
+("/tmp/lock/lvm"), and unit tmp.mount is to mount /tmp.
+So start lvm2-monitor.service after tmp.mount
+
+Upstream-Status: Inappropriate [oe specific]
+
+Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
+---
+ scripts/lvm2_monitoring_systemd_red_hat.service.in | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/scripts/lvm2_monitoring_systemd_red_hat.service.in b/scripts/lvm2_monitoring_systemd_red_hat.service.in
+index 22238b7..93b2bee 100644
+--- a/scripts/lvm2_monitoring_systemd_red_hat.service.in
++++ b/scripts/lvm2_monitoring_systemd_red_hat.service.in
+@@ -2,7 +2,7 @@
+ Description=Monitoring of LVM2 mirrors, snapshots etc. using dmeventd or progress polling
+ Documentation=man:dmeventd(8) man:lvcreate(8) man:lvchange(8) man:vgchange(8)
+ Requires=dm-event.socket lvm2-lvmetad.socket
+-After=dm-event.socket dm-event.service lvm2-lvmetad.socket lvm2-activation.service lvm2-lvmetad.service
++After=dm-event.socket dm-event.service lvm2-lvmetad.socket lvm2-activation.service lvm2-lvmetad.service tmp.mount
+ Before=local-fs-pre.target
+ DefaultDependencies=no
+ Conflicts=shutdown.target
+-- 
+1.8.3.1
+

meta-oe/recipes-support/lvm2/files/lvm.conf

@@ -214,7 +214,7 @@ global {
 
     # Local non-LV directory that holds file-based locks while commands are
     # in progress.  A directory like /tmp that may get wiped on reboot is OK.
-    locking_dir = "/var/lock/lvm"
+    locking_dir = "/tmp/lock/lvm"
 
     # Other entries can go here to allow you to load shared libraries
     # e.g. if support for LVM1 metadata was compiled as a shared library use

meta-oe/recipes-support/lvm2/lvm2.inc

@@ -15,6 +15,7 @@ SRC_URI = "ftp://sources.redhat.com/pub/lvm2/old/LVM2.${PV}.tgz \
            file://0004-tweak-MODPROBE_CMD-for-cross-compile.patch \
            file://0001-Avoid-bashisms-in-init-scripts.patch \
            file://0005-do-not-build-manual.patch \
+           file://0006-start-lvm2-monitor.service-after-tmp.mount.patch \
            "
 S = "${WORKDIR}/LVM2.${PV}"