[LTP] [PATCH v3 1/4] Hugetlb: Add new tst_test options for hugeltb test support

[Tarun Sahu]

Most of libhugetlbfs test require mounted hugetlbfs and random opened
unlinked file for follow-up test actions.

Here, this patch adds two new field in tst_test struct(include/tst_test.h)
which user can set if the test requires mounted hugetlbfs and other one
for if test requires opened unlinked file.

Signed-off-by: Tarun Sahu <tsahu@linux.ibm.com>
---
 include/tst_test.h | 20 +++++++++++++++++-
 lib/tst_test.c     | 51 +++++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 67 insertions(+), 4 deletions(-)

diff --git a/include/tst_test.h b/include/tst_test.h
index a69965b95..f36382ae9 100644
--- a/include/tst_test.h
+++ b/include/tst_test.h
@@ -131,7 +131,7 @@ struct tst_tag {
 };
 
 extern unsigned int tst_variant;
-
+extern int tst_hugetlb_fd;
 #define TST_NO_HUGEPAGES ((unsigned long)-1)
 
 #define TST_UNLIMITED_RUNTIME (-1)
@@ -176,6 +176,18 @@ struct tst_test {
 	int all_filesystems:1;
 	int skip_in_lockdown:1;
 	int skip_in_compat:1;
+	/*
+	 * If set, the test function will create a hugetlbfs mount point
+	 * at /tmp/xxxxxx, where xxxxxx is a random string.
+	 */
+	int needs_hugetlbfs:1;
+	/*
+	 * If set, the test function will create and open a random file
+	 * under mounted hugetlbfs. To use this option, needs_hugetlbfs must
+	 * be set. The file descriptior will be set in tst_hugetlb_fd.
+	 * The close(tst_hugetlb_fd) will be called on test exit(cleanup).
+	 */
+	int needs_unlinked_hugetlb_file:1;
 
 	/*
 	 * The skip_filesystems is a NULL terminated list of filesystems the
@@ -357,6 +369,12 @@ unsigned int tst_remaining_runtime(void);
  */
 void tst_set_max_runtime(int max_runtime);
 
+/*
+ * Create and open a random file inside the given dir path.
+ * It unlinks the file after opening and return file descriptor.
+ */
+int tst_create_unlinked_file(const char *path);
+
 /*
  * Returns path to the test temporary directory in a newly allocated buffer.
  */
diff --git a/lib/tst_test.c b/lib/tst_test.c
index 8ccde1629..43cba1004 100644
--- a/lib/tst_test.c
+++ b/lib/tst_test.c
@@ -925,7 +925,8 @@ static int needs_tmpdir(void)
 	       tst_test->needs_device ||
 	       tst_test->mntpoint ||
 	       tst_test->resource_files ||
-	       tst_test->needs_checkpoints;
+	       tst_test->needs_checkpoints ||
+		   tst_test->needs_hugetlbfs;
 }
 
 static void copy_resources(void)
@@ -1021,6 +1022,30 @@ static void prepare_and_mount_dev_fs(const char *mntpoint)
 	}
 }
 
+static void prepare_and_mount_hugetlb_fs(void)
+{
+	tst_test->mntpoint = tst_get_tmpdir();
+	SAFE_MOUNT("none", tst_test->mntpoint, "hugetlbfs", 0, NULL);
+	mntpoint_mounted = 1;
+}
+
+int tst_create_unlinked_file(const char *path)
+{
+	char template[PATH_MAX];
+	int fd;
+
+	snprintf(template, PATH_MAX, "%s/ltp_%.3sXXXXXX",
+			path, TCID);
+
+	fd = mkstemp(template);
+	if (fd < 0)
+		tst_brk(TBROK | TERRNO,
+			 "%s: mkstemp(%s) failed", __func__, template);
+
+	SAFE_UNLINK(template);
+	return fd;
+}
+
 static const char *limit_tmpfs_mount_size(const char *mnt_data,
 		char *buf, size_t buf_size, const char *fs_type)
 {
@@ -1094,6 +1119,8 @@ static void do_cgroup_requires(void)
 	tst_cg_init();
 }
 
+int tst_hugetlb_fd = -1;
+
 static void do_setup(int argc, char *argv[])
 {
 	if (!tst_test)
@@ -1217,6 +1244,17 @@ static void do_setup(int argc, char *argv[])
 		}
 	}
 
+	if (tst_test->needs_hugetlbfs)
+		prepare_and_mount_hugetlb_fs();
+
+	if (tst_test->needs_unlinked_hugetlb_file) {
+		if (!(tst_test->needs_hugetlbfs)) {
+			tst_brk(TBROK, "Option needs_unlinked_hugetlb_file "
+					"requires option needs_hugetlbfs");
+		}
+		tst_hugetlb_fd = tst_create_unlinked_file(tst_test->mntpoint);
+	}
+
 	if (tst_test->needs_device && !mntpoint_mounted) {
 		tdev.dev = tst_acquire_device_(NULL, tst_test->dev_min_size);
 
@@ -1299,8 +1337,15 @@ static void do_cleanup(void)
 	if (ovl_mounted)
 		SAFE_UMOUNT(OVL_MNT);
 
-	if (mntpoint_mounted)
-		tst_umount(tst_test->mntpoint);
+	if (tst_hugetlb_fd >= 0)
+		SAFE_CLOSE(tst_hugetlb_fd);
+
+	if (mntpoint_mounted) {
+		if (tst_test->needs_hugetlbfs)
+			SAFE_UMOUNT(tst_test->mntpoint);
+		else
+			tst_umount(tst_test->mntpoint);
+	}
 
 	if (tst_test->needs_device && tdev.dev)
 		tst_release_device(tdev.dev);
-- 
2.31.1