[ndctl PATCH v2] cxl/test: add a test to {read,write,zero}-labels

[Vishal Verma <vishal.l.verma@intel.com>]

Add a unit test to test writing, reading, and zeroing LSA aread for
cxl_test based memdevs using ndctl commands, and reading using cxl-cli
commands to exercise that route as much as possible.

Note that writing using cxl-cli requires a bit more enabling to enable,
as the corresponding nvdimm-bridge object will need to be disabled
first.

Cc: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
 test/cxl-labels.sh | 69 ++++++++++++++++++++++++++++++++++++++++++++++
 test/meson.build   |  2 ++
 2 files changed, 71 insertions(+)
 create mode 100644 test/cxl-labels.sh

Changes since v1[1]:
- Collect Reviewed-by's
- Add a read-labels using cxl-cli in addition to the ndctl operations.

[1]: https://lore.kernel.org/linux-cxl/20220713075157.411479-1-vishal.l.verma@intel.com/

diff --git a/test/cxl-labels.sh b/test/cxl-labels.sh
new file mode 100644
index 0000000..e782e2d
--- /dev/null
+++ b/test/cxl-labels.sh
@@ -0,0 +1,69 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2022 Intel Corporation. All rights reserved.
+
+. $(dirname $0)/common
+
+rc=1
+
+set -ex
+
+trap 'err $LINENO' ERR
+
+check_prereq "jq"
+
+modprobe -r cxl_test
+modprobe cxl_test
+udevadm settle
+
+test_label_ops()
+{
+	nmem="$1"
+	lsa=$(mktemp /tmp/lsa-$nmem.XXXX)
+	lsa_read=$(mktemp /tmp/lsa-read-$nmem.XXXX)
+
+	# determine LSA size
+	"$NDCTL" read-labels -o "$lsa_read" "$nmem"
+	lsa_size=$(stat -c %s "$lsa_read")
+
+	dd "if=/dev/urandom" "of=$lsa" "bs=$lsa_size" "count=1"
+	"$NDCTL" write-labels -i "$lsa" "$nmem"
+	"$NDCTL" read-labels -o "$lsa_read" "$nmem"
+
+	# compare what was written vs read
+	diff "$lsa" "$lsa_read"
+
+	# zero the LSA and test
+	"$NDCTL" zero-labels "$nmem"
+	dd "if=/dev/zero" "of=$lsa" "bs=$lsa_size" "count=1"
+	"$NDCTL" read-labels -o "$lsa_read" "$nmem"
+	diff "$lsa" "$lsa_read"
+
+	# cleanup
+	rm "$lsa" "$lsa_read"
+}
+
+test_label_ops_cxl()
+{
+	mem="$1"
+	lsa_read=$(mktemp /tmp/lsa-read-$mem.XXXX)
+
+	"$CXL" read-labels -o "$lsa_read" "$mem"
+	rm "$lsa_read"
+}
+
+# test reading labels directly through cxl-cli
+readarray -t mems < <("$CXL" list -b cxl_test -Mi | jq -r '.[].memdev')
+
+for mem in ${mems[@]}; do
+	test_label_ops_cxl "$mem"
+done
+
+# find nmem devices corresponding to cxl memdevs
+readarray -t nmems < <("$NDCTL" list -b cxl_test -Di | jq -r '.[].dev')
+
+for nmem in ${nmems[@]}; do
+	test_label_ops "$nmem"
+done
+
+modprobe -r cxl_test
diff --git a/test/meson.build b/test/meson.build
index fbcfc08..687a71f 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -152,6 +152,7 @@ pfn_meta_errors = find_program('pfn-meta-errors.sh')
 track_uuid = find_program('track-uuid.sh')
 cxl_topo = find_program('cxl-topology.sh')
 cxl_region = find_program('cxl-region-create.sh')
+cxl_labels = find_program('cxl-labels.sh')
 
 tests = [
   [ 'libndctl',               libndctl,		  'ndctl' ],
@@ -178,6 +179,7 @@ tests = [
   [ 'track-uuid.sh',          track_uuid,	  'ndctl' ],
   [ 'cxl-topology.sh',	      cxl_topo,		  'cxl'   ],
   [ 'cxl-region-create.sh',   cxl_region,	  'cxl'   ],
+  [ 'cxl-labels.sh',          cxl_labels,	  'cxl'   ],
 ]
 
 if get_option('destructive').enabled()
-- 
2.36.1