[PATCH v3] generic/728: Add a test for xattr ctime updates

[Anna Schumaker <anna@kernel.org>]

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

The NFS client wasn't updating ctime after a setxattr request. This is a
test written while fixing the bug.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

---
v3:
 - Add a 2 second sleep before changing the xattr

v2:
 - Move test to generic/
 - Address comments from the mailing list
---
 tests/generic/728     | 43 +++++++++++++++++++++++++++++++++++++++++++
 tests/generic/728.out |  2 ++
 2 files changed, 45 insertions(+)
 create mode 100755 tests/generic/728
 create mode 100644 tests/generic/728.out

diff --git a/tests/generic/728 b/tests/generic/728
new file mode 100755
index 000000000000..8e52eb4b219c
--- /dev/null
+++ b/tests/generic/728
@@ -0,0 +1,43 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2023 Netapp Inc., All Rights Reserved.
+#
+# FS QA Test 728
+#
+# Test a bug where the NFS client wasn't sending a post-op GETATTR to the
+# server after setting an xattr, resulting in `stat` reporting a stale ctime.
+#
+. ./common/preamble
+_begin_fstest auto quick attr
+
+# Import common functions
+. ./common/attr
+
+# real QA test starts here
+_supported_fs generic
+_require_test
+_require_attrs
+
+rm -rf $TEST_DIR/testfile
+touch $TEST_DIR/testfile
+
+
+_check_xattr_op()
+{
+  what=$1
+  shift 1
+
+  before_ctime=$(stat -c %z $TEST_DIR/testfile)
+  sleep 2
+  $SETFATTR_PROG $* $TEST_DIR/testfile
+  after_ctime=$(stat -c %z $TEST_DIR/testfile)
+
+  test "$before_ctime" != "$after_ctime" || echo "Expected ctime to change after $what."
+}
+
+_check_xattr_op setxattr -n user.foobar -v 123
+_check_xattr_op removexattr -x user.foobar
+
+echo "Silence is golden"
+status=0
+exit
diff --git a/tests/generic/728.out b/tests/generic/728.out
new file mode 100644
index 000000000000..ab39f45fe5da
--- /dev/null
+++ b/tests/generic/728.out
@@ -0,0 +1,2 @@
+QA output created by 728
+Silence is golden
-- 
2.40.1