[Devel] [PATCH libvzctl 2/4] vz-cpt: NFS suppress added

[Stanislav Kinsburskiy]

This patch add usage of new special toggle, which suppresses NFS requests to
server when enabled.
Required to allow criu to dump NFS mounts.

Signed-off-by: Stanislav Kinsburskiy <skinsbursky at virtuozzo.com>
---
 scripts/vz-cpt.in |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/scripts/vz-cpt.in b/scripts/vz-cpt.in
index f79f665..3d7198a 100755
--- a/scripts/vz-cpt.in
+++ b/scripts/vz-cpt.in
@@ -56,8 +56,19 @@ function cg_dump_props {
 	return 0
 }
 
+function suppress_nfs {
+	value=0
+	path=/proc/$VE_PID/net/nfsfs/suppress_revalidate
+
+	[ "$1" == "true" ] && value=1
+	[ -w  $path ] || return 0
+
+	echo $value > /proc/$VE_PID/net/nfsfs/suppress_revalidate
+}
+
 mkdir -p $dumpdir &&
 cg_dump_props $dumpdir &&
+suppress_nfs true &&
 criu dump -v$CRIU_LOGLEVEL -o dump.log				\
 		--file-locks				\
 		--tcp-established			\
@@ -74,6 +85,7 @@ criu dump -v$CRIU_LOGLEVEL -o dump.log				\
 		$CRIU_EXTRA_ARGS
 
 if [ $? -ne 0 ]; then
+	suppress_nfs false
         [ -d $VE_DUMP_DIR.fail ] && rm -rf $VE_DUMP_DIR.fail
         mv -f $dumpdir $VE_DUMP_DIR.fail
         echo Failed to checkpoint the Container