[PATCH 1/1] df01.sh: Use own fsfreeze implementation for XFS

[Petr Vorel <pvorel@suse.cz>]

df01.sh started to fail on XFS on certain configuration since mkfs.xfs
and kernel 5.19. Implement fsfreeze instead of introducing external
dependency. NOTE: implementation could fail on other filesystems
(EOPNOTSUPP on exfat, ntfs, vfat).

Suggested-by: Darrick J. Wong <djwong@kernel.org>
Suggested-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
Hi,

FYI the background of this issue:
https://lore.kernel.org/ltp/Yv5oaxsX6z2qxxF3@magnolia/
https://lore.kernel.org/ltp/974cc110-d47e-5fae-af5f-e2e610720e2d@redhat.com/

@LTP developers: not sure if the consensus is to avoid LTP API
completely (even use it just with TST_NO_DEFAULT_MAIN), if required I
can rewrite to use it just to get SAFE_*() macros (like
testcases/lib/tst_checkpoint.c) or even with tst_test workarounds
(testcases/lib/tst_get_free_pids.c).

Kind regards,
Petr

 testcases/commands/df/Makefile        |  4 +-
 testcases/commands/df/df01.sh         |  3 ++
 testcases/commands/df/df01_fsfreeze.c | 55 +++++++++++++++++++++++++++
 3 files changed, 61 insertions(+), 1 deletion(-)
 create mode 100644 testcases/commands/df/df01_fsfreeze.c

diff --git a/testcases/commands/df/Makefile b/testcases/commands/df/Makefile
index 2787bb43a..1e0b4283a 100644
--- a/testcases/commands/df/Makefile
+++ b/testcases/commands/df/Makefile
@@ -1,11 +1,13 @@
 # SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (c) Linux Test Project, 2021-2022
 # Copyright (c) 2015 Fujitsu Ltd.
-# Author:Zhang Jin <jy_zhangjin@cn.fujitsu.com>
+# Author: Zhang Jin <jy_zhangjin@cn.fujitsu.com>
 
 top_srcdir		?= ../../..
 
 include $(top_srcdir)/include/mk/env_pre.mk
 
 INSTALL_TARGETS		:= df01.sh
+MAKE_TARGETS			:= df01_fsfreeze
 
 include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/commands/df/df01.sh b/testcases/commands/df/df01.sh
index ae0449c3c..c59d2a01d 100755
--- a/testcases/commands/df/df01.sh
+++ b/testcases/commands/df/df01.sh
@@ -46,6 +46,9 @@ df_test()
 
 	ROD_SILENT rm -rf $TST_MNTPOINT/testimg
 
+	# ensure free space change can be seen by statfs
+	[ "$fs" = "xfs" ] && ROD_SILENT df01_fsfreeze $TST_MNTPOINT
+
 	# flush file system buffers, then we can get the actual sizes.
 	sync
 }
diff --git a/testcases/commands/df/df01_fsfreeze.c b/testcases/commands/df/df01_fsfreeze.c
new file mode 100644
index 000000000..d47e1b01a
--- /dev/null
+++ b/testcases/commands/df/df01_fsfreeze.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2010 Hajime Taira <htaira@redhat.com>
+ * Copyright (c) 2010 Masatake Yamato <yamato@redhat.com>
+ * Copyright (c) 2022 Petr Vorel <pvorel@suse.cz>
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/fs.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#define err_exit(...) ({ \
+	fprintf(stderr, __VA_ARGS__); \
+	if (errno) \
+		fprintf(stderr, ": %s (%d)", strerror(errno), errno); \
+	fprintf(stderr, "\n"); \
+	exit(EXIT_FAILURE); \
+})
+
+int main(int argc, char *argv[])
+{
+	int fd;
+	struct stat sb;
+
+	if (argc < 2)
+		err_exit("USAGE: df01_fsfreeze <mountpoint>");
+
+	fd = open(argv[1], O_RDONLY);
+	if (fd < 0)
+		err_exit("open '%s' failed", argv[1]);
+
+	if (fstat(fd, &sb) == -1)
+		err_exit("stat of '%s' failed", argv[1]);
+
+	if (!S_ISDIR(sb.st_mode))
+		err_exit("%s: is not a directory", argv[1]);
+
+	if (ioctl(fd, FIFREEZE, 0) < 0)
+		err_exit("ioctl FIFREEZE on '%s' failed", argv[1]);
+
+	usleep(100);
+
+	if (ioctl(fd, FITHAW, 0) < 0)
+		err_exit("ioctl FITHAW on '%s' failed", argv[1]);
+
+	close(fd);
+
+	return EXIT_SUCCESS;
+}
-- 
2.37.3