[LTP] [PATCH v2 07/10] Add statmount03 test

[Andrea Cervesato]

From: Andrea Cervesato <andrea.cervesato@suse.com>

This test verifies that statmount() is correctly reading mount
information (mount id, parent mount id, mount attributes etc.)
using STATMOUNT_MNT_BASIC.

Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
---
 runtest/syscalls                              |  1 +
 .../kernel/syscalls/statmount/.gitignore      |  1 +
 .../kernel/syscalls/statmount/statmount03.c   | 99 +++++++++++++++++++
 3 files changed, 101 insertions(+)
 create mode 100644 testcases/kernel/syscalls/statmount/statmount03.c

diff --git a/runtest/syscalls b/runtest/syscalls
index 5f1df42ca..116106521 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -1539,6 +1539,7 @@ stat04_64 symlink01 -T stat04_64
 
 statmount01 statmount01
 statmount02 statmount02
+statmount03 statmount03
 
 statfs01 statfs01
 statfs01_64 statfs01_64
diff --git a/testcases/kernel/syscalls/statmount/.gitignore b/testcases/kernel/syscalls/statmount/.gitignore
index a30b9565f..2a02bf721 100644
--- a/testcases/kernel/syscalls/statmount/.gitignore
+++ b/testcases/kernel/syscalls/statmount/.gitignore
@@ -1,2 +1,3 @@
 statmount01
 statmount02
+statmount03
diff --git a/testcases/kernel/syscalls/statmount/statmount03.c b/testcases/kernel/syscalls/statmount/statmount03.c
new file mode 100644
index 000000000..6140940bd
--- /dev/null
+++ b/testcases/kernel/syscalls/statmount/statmount03.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2024 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
+ */
+
+/**
+ * [Description]
+ *
+ * This test verifies that statmount() is correctly reading mount information
+ * (mount id, parent mount id, mount attributes etc.) using STATMOUNT_MNT_BASIC.
+ *
+ * [Algorithm]
+ *
+ * * create a mount point
+ * * create a new parent folder inside the mount point and obtain its mount info
+ * * create the new "/" mount folder and obtain its mount info
+ * * run statmount() on the mount point using STATMOUNT_MNT_BASIC
+ * * read results and check if mount info are correct
+ */
+
+#include "statmount.h"
+#include "lapi/stat.h"
+#include "lapi/sched.h"
+
+#define MNTPOINT "mntpoint"
+#define MYPARENT MNTPOINT "/myroot"
+
+static uint64_t root_id;
+static uint64_t root_id_old;
+static uint64_t parent_id;
+static uint64_t parent_id_old;
+static struct statmount *st_mount;
+
+static void run(void)
+{
+	memset(st_mount, 0, sizeof(struct statmount));
+
+	TST_EXP_PASS(statmount(
+		root_id,
+		STATMOUNT_MNT_BASIC,
+		st_mount,
+		sizeof(struct statmount),
+		0));
+
+	if (TST_RET == -1)
+		return;
+
+	TST_EXP_EQ_LI(st_mount->mask, STATMOUNT_MNT_BASIC);
+	TST_EXP_EQ_LI(st_mount->size, sizeof(struct statmount));
+	TST_EXP_EQ_LI(st_mount->mnt_id, root_id);
+	TST_EXP_EQ_LI(st_mount->mnt_id_old, root_id_old);
+	TST_EXP_EQ_LI(st_mount->mnt_parent_id, parent_id);
+	TST_EXP_EQ_LI(st_mount->mnt_parent_id_old, parent_id_old);
+	TST_EXP_EQ_LI(st_mount->mnt_propagation, MS_PRIVATE);
+}
+
+static void setup(void)
+{
+	struct statx sx;
+
+	SAFE_UNSHARE(CLONE_NEWNS);
+	SAFE_MKDIR(MYPARENT, 0700);
+
+	SAFE_STATX(AT_FDCWD, MYPARENT, 0, STATX_MNT_ID_UNIQUE, &sx);
+	parent_id = sx.stx_mnt_id;
+
+	SAFE_STATX(AT_FDCWD, MYPARENT, 0, STATX_MNT_ID, &sx);
+	parent_id_old = sx.stx_mnt_id;
+
+	SAFE_MOUNT("", "/", NULL, MS_REC | MS_PRIVATE, NULL);
+	SAFE_MOUNT(MYPARENT, MYPARENT, NULL, MS_BIND, NULL);
+	SAFE_CHROOT(MYPARENT);
+	SAFE_CHDIR("/");
+
+	SAFE_STATX(AT_FDCWD, "/", 0, STATX_MNT_ID_UNIQUE, &sx);
+	root_id = sx.stx_mnt_id;
+
+	SAFE_STATX(AT_FDCWD, "/", 0, STATX_MNT_ID, &sx);
+	root_id_old = sx.stx_mnt_id;
+}
+
+static struct tst_test test = {
+	.test_all = run,
+	.setup = setup,
+	.min_kver = "6.8",
+	.needs_tmpdir = 1,
+	.format_device = 1,
+	.mount_device = 1,
+	.mntpoint = MNTPOINT,
+	.all_filesystems = 1,
+	.skip_filesystems = (const char *const []) {
+		"fuse",
+		NULL
+	},
+	.bufs = (struct tst_buffers []) {
+		{&st_mount, .size = sizeof(struct statmount)},
+		{}
+	}
+};
-- 
2.35.3