[PATCH v3 6/9] syscalls/fanotify21: Support submission of debugfs commands

[Gabriel Krisman Bertazi <krisman@collabora.com>]

In order to test FAN_FS_ERROR, we want to corrupt the filesystem.  The
easiest way to do it is by using debugfs.  Add a small helper to issue
debugfs requests.  Since most likely this will be the only testcase to
need this, don't bother making it a proper helper for now.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
---
changes since v1:
  - Add .needs_cmds to require debugfs
---
 testcases/kernel/syscalls/fanotify/fanotify21.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/testcases/kernel/syscalls/fanotify/fanotify21.c b/testcases/kernel/syscalls/fanotify/fanotify21.c
index 95c988821a34..43e606c27372 100644
--- a/testcases/kernel/syscalls/fanotify/fanotify21.c
+++ b/testcases/kernel/syscalls/fanotify/fanotify21.c
@@ -49,6 +49,13 @@ static void trigger_fs_abort(void)
                   MS_REMOUNT|MS_RDONLY, "abort");
 }
 
+static void do_debugfs_request(const char *dev, char *request)
+{
+	const char *cmd[] = {"debugfs", "-w", dev, "-R", request, NULL};
+
+	SAFE_CMD(cmd, NULL, NULL);
+}
+
 static struct test_case {
 	char *name;
 	int error;
@@ -228,7 +235,11 @@ static struct tst_test test = {
 	.mntpoint = MOUNT_PATH,
 	.all_filesystems = 0,
 	.needs_root = 1,
-	.dev_fs_type = "ext4"
+	.dev_fs_type = "ext4",
+	.needs_cmds = (const char *[]) {
+		"debugfs",
+		NULL
+	}
 };
 
 #else
-- 
2.33.0