ioctl_loop01.c: Add new support .needs_cmds

Link: https://lore.kernel.org/ltp/20260109061716.20258-4-wegao@suse.com/
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>
Signed-off-by: Wei Gao <wegao@suse.com>

Author: coolgw

testcases/kernel/syscalls/ioctl/ioctl_loop01.c

@@ -79,23 +79,6 @@ static void check_loop_value(int set_flag, int get_flag, int autoclear_field)
 
 static void verify_ioctl_loop(void)
 {
-	int ret;
-	const char *const cmd_parted[] = {"parted", "-s", dev_path, "mklabel", "msdos", "mkpart",
-					"primary", "ext4", "1M", "10M", NULL};
-
-	tst_fill_file("test.img", 0, 1024 * 1024, 10);
-	tst_attach_device(dev_path, "test.img");
-
-	ret = tst_cmd(cmd_parted, NULL, NULL, TST_CMD_PASS_RETVAL);
-	if (!ret)
-		parted_sup = 1;
-	else if (ret == 255)
-		tst_res(TCONF, "parted binary not installed or failed");
-	else
-		tst_res(TCONF, "parted exited with %i", ret);
-
-	attach_flag = 1;
-
 	TST_ASSERT_INT(partscan_path, 0);
 	TST_ASSERT_INT(autoclear_path, 0);
 	TST_ASSERT_STR(backing_path, backing_file_path);
@@ -114,10 +97,23 @@ static void verify_ioctl_loop(void)
 
 static void setup(void)
 {
+	parted_sup = tst_cmd_present("parted");
+
+	const char *const cmd_parted[] = {"parted", "-s", dev_path, "mklabel", "msdos", "mkpart",
+	                                  "primary", "ext4", "1M", "10M", NULL};
+
 	dev_num = tst_find_free_loopdev(dev_path, sizeof(dev_path));
 	if (dev_num < 0)
 		tst_brk(TBROK, "Failed to find free loop device");
 
+	tst_fill_file("test.img", 0, 1024 * 1024, 10);
+
+	tst_attach_device(dev_path, "test.img");
+	attach_flag = 1;
+
+	if (parted_sup)
+		SAFE_CMD(cmd_parted, NULL, NULL);
+
 	sprintf(partscan_path, "/sys/block/loop%d/loop/partscan", dev_num);
 	sprintf(autoclear_path, "/sys/block/loop%d/loop/autoclear", dev_num);
 	sprintf(backing_path, "/sys/block/loop%d/loop/backing_file", dev_num);
@@ -149,5 +145,9 @@ static struct tst_test test = {
 		{"linux-git", "6ac92fb5cdff"},
 		{}
 	},
+	.needs_cmds = (struct tst_cmd[]) {
+		{.cmd = "parted", .optional = 1},
+		{}
+	},
 	.needs_tmpdir = 1,
 };