[PATCH blktests v3 02/20] nvme/rc: silence fcloop cleanup failures

[Daniel Wagner <dwagner@suse.de>]

When the ctl file is missing we are logging

  tests/nvme/rc: line 265: /sys/class/fcloop/ctl/del_target_port: No such file or directory
  tests/nvme/rc: line 257: /sys/class/fcloop/ctl/del_local_port: No such file or directory
  tests/nvme/rc: line 249: /sys/class/fcloop/ctl/del_remote_port: No such file or directory

because the first redirect operator fails. Also it's not possible to
redirect the 'echo' error to /dev/null, because it's a builtin command
which escapes the stderr redirect operator (why?).

Anyway, the simplest way to catch this error is to first check if the
control file exists before attempting to write to it.

Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
 tests/nvme/rc | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/tests/nvme/rc b/tests/nvme/rc
index 78d84af72e73..865c8c351159 100644
--- a/tests/nvme/rc
+++ b/tests/nvme/rc
@@ -234,7 +234,10 @@ _nvme_fcloop_del_rport() {
 	local remote_wwpn="$4"
 	local loopctl=/sys/class/fcloop/ctl
 
-	echo "wwnn=${remote_wwnn},wwpn=${remote_wwpn}" > ${loopctl}/del_remote_port 2> /dev/null
+	if [[ ! -f "${loopctl}/del_remote_port" ]]; then
+		return
+	fi
+	echo "wwnn=${remote_wwnn},wwpn=${remote_wwpn}" > "${loopctl}/del_remote_port"
 }
 
 _nvme_fcloop_del_lport() {
@@ -242,7 +245,10 @@ _nvme_fcloop_del_lport() {
 	local wwpn="$2"
 	local loopctl=/sys/class/fcloop/ctl
 
-	echo "wwnn=${wwnn},wwpn=${wwpn}" > ${loopctl}/del_local_port 2> /dev/null
+	if [[ ! -f "${loopctl}/del_local_port" ]]; then
+		return
+	fi
+	echo "wwnn=${wwnn},wwpn=${wwpn}" > "${loopctl}/del_local_port"
 }
 
 _nvme_fcloop_del_tport() {
@@ -250,7 +256,10 @@ _nvme_fcloop_del_tport() {
 	local wwpn="$2"
 	local loopctl=/sys/class/fcloop/ctl
 
-	echo "wwnn=${wwnn},wwpn=${wwpn}" > ${loopctl}/del_target_port 2> /dev/null
+	if [[ ! -f "${loopctl}/del_target_port" ]]; then
+		return
+	fi
+	echo "wwnn=${wwnn},wwpn=${wwpn}" > "${loopctl}/del_target_port"
 }
 
 _cleanup_fcloop() {
-- 
2.44.0