[PATCH v2] generic: add OFD lock tests

[Xiong Zhou <xzhou@redhat.com>]

The basic idea is placing a type of lock, eg WRLCK, on
a testfile in SCRATCH_MNT, then do fcntl getlk with a
type of lock, eg RDLCK, checking the returned flock
struct to see if it works fine.

We can also test these situations:
that the two locks are conflicting or not;
that open testfile RDONLY or RDWR.

Signed-off-by: Xiong Zhou <xzhou@redhat.com>
---

v2:
  add helper checking if OFD lock is available.
  mv simple getlk WRLCK test to the helper.
  add macro definitions in c programme to avoid build errors.

 .gitignore            |   1 +
 common/rc             |   8 +++
 src/Makefile          |   3 +-
 src/t_ofd_locks.c     | 150 ++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/generic/463     | 128 ++++++++++++++++++++++++++++++++++++++++++
 tests/generic/463.out |   2 +
 tests/generic/group   |   1 +
 7 files changed, 292 insertions(+), 1 deletion(-)
 create mode 100644 src/t_ofd_locks.c
 create mode 100755 tests/generic/463
 create mode 100644 tests/generic/463.out

diff --git a/.gitignore b/.gitignore
index ae7ef87..2824c3d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -126,6 +126,7 @@
 /src/t_mmap_write_ro
 /src/t_mmap_writev
 /src/t_mtab
+/src/t_ofd_locks
 /src/t_readdir_1
 /src/t_readdir_2
 /src/t_rename_overwrite
diff --git a/common/rc b/common/rc
index 53bbb11..79f97a4 100644
--- a/common/rc
+++ b/common/rc
@@ -3310,6 +3310,14 @@ _require_test_fcntl_advisory_locks()
 		_notrun "Require fcntl advisory locks support"
 }
 
+_require_scratch_fcntl_ofd_locks()
+{
+	# getlk with wrlck only, expect unlck
+	touch $SCRATCH_MNT/testfile
+	src/t_ofd_locks $SCRATCH_MNT/testfile 0 1 0 1
+	[ $? -ne 1 ] && _notrun "Require fcntl OFD locks support"
+}
+
 _require_test_lsattr()
 {
 	testio=$(lsattr -d $TEST_DIR 2>&1)
diff --git a/src/Makefile b/src/Makefile
index 3eb25b1..f37af74 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -13,7 +13,8 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \
 	multi_open_unlink dmiperf unwritten_sync genhashnames t_holes \
 	t_mmap_writev t_truncate_cmtime dirhash_collide t_rename_overwrite \
 	holetest t_truncate_self t_mmap_dio af_unix t_mmap_stale_pmd \
-	t_mmap_cow_race t_mmap_fallocate fsync-err t_mmap_write_ro
+	t_mmap_cow_race t_mmap_fallocate fsync-err t_mmap_write_ro \
+	t_ofd_locks
 
 LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
 	preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
diff --git a/src/t_ofd_locks.c b/src/t_ofd_locks.c
new file mode 100644
index 0000000..2aab48b
--- /dev/null
+++ b/src/t_ofd_locks.c
@@ -0,0 +1,150 @@
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+/*
+ * In distributions that do not have these macros ready in
+ * glibc-headers, compilation fails. Adding them here to avoid
+ * build errors, relevant tests would fail at the helper which
+ * requires OFD locks support and notrun if the kernel does not
+ * support OFD locks. If the kernel does support OFD locks,
+ * we are good to go.
+ *
+ */
+#ifndef F_OFD_GETLK
+#define F_OFD_GETLK    36
+#endif
+
+#ifndef F_OFD_SETLK
+#define F_OFD_SETLK    37
+#endif
+
+#ifndef F_OFD_SETLKW
+#define F_OFD_SETLKW   38
+#endif
+
+void err_exit(int fd, char *op)
+{
+	fprintf(stderr, "%s: %s\n", op, strerror(errno));
+	if (fd > 0)
+		close(fd);
+	exit(errno);
+}
+
+void set_lock(int fd, struct flock *flkp)
+{
+	if (fcntl(fd, F_OFD_SETLKW, flkp) < 0)
+		err_exit(fd, "ofd_setlkw");
+}
+
+void get_lock(int fd, struct flock *flkp)
+{
+	if (fcntl(fd, F_OFD_GETLK, flkp) < 0)
+		err_exit(fd, "ofd_getlk");
+}
+
+void wait_exit(int fd)
+{
+	sleep(1);
+	close(fd);
+	exit(0);
+}
+
+int main(int argc, char **argv)
+{
+	int fd;
+	int lock_cmd;
+	int lock_rw;
+	int lock_start = 0;
+	int open_rw = 1;
+
+	struct flock flk = {
+		.l_whence = SEEK_SET,
+		.l_start = 0,
+		.l_len = 10,     /* lock range [0,9] */
+		.l_type = F_RDLCK,
+	};
+
+	/* lock_cmd : 1 <--> setlk
+	 *            0 <--> getlk
+	 *
+	 *  lock_rw : 1 <--> set/get wrlck
+	 *            0 <--> set/get rdlck
+	 *
+	 * lock_start : l_start to getlk
+	 *
+	 *  open_rw : 1 <--> open file RDWR
+	 *            0 <--> open file RDONLY
+	 */
+
+	if (argc < 5) {
+		printf("Usage: %s filename lock_cmd lock_rw lock_start open_rw\n", argv[0]);
+		return 1;
+	}
+
+	lock_cmd = atoi(argv[2]);
+	lock_rw = atoi(argv[3]);
+	lock_start = atoi(argv[4]);
+	open_rw = atoi(argv[5]);
+
+	if (open_rw == 0)
+		fd = open(argv[1], O_RDONLY);
+	else
+		fd = open(argv[1], O_RDWR);
+
+	if (fd < 0)
+		err_exit(fd, "open");
+
+	/* set rdlck */
+	if (lock_cmd == 1 && lock_rw == 0) {
+
+		flk.l_type = F_RDLCK;
+		set_lock(fd, &flk);
+		wait_exit(fd);
+	}
+
+	/* set wrlck */
+	if (lock_cmd == 1 && lock_rw == 1) {
+
+		flk.l_type = F_WRLCK;
+		set_lock(fd, &flk);
+		wait_exit(fd);
+	}
+
+	/* getlck */
+	if (lock_cmd == 0) {
+
+		if (lock_rw == 1)
+			flk.l_type = F_WRLCK;
+		else
+			flk.l_type = F_RDLCK;
+
+		flk.l_start = lock_start;
+
+		get_lock(fd, &flk);
+		close(fd);
+
+		switch (flk.l_type) {
+		case F_UNLCK:
+			return 1; // lock can be placed
+		case F_RDLCK:
+			return 2; // got rdlck
+		case F_WRLCK:
+			return 3; // got wrlck
+		default:
+			return 0;
+		}
+	}
+
+	close(fd);
+	return 0;
+}
diff --git a/tests/generic/463 b/tests/generic/463
new file mode 100755
index 0000000..ad4f0dc
--- /dev/null
+++ b/tests/generic/463
@@ -0,0 +1,128 @@
+#! /bin/bash
+# FS QA Test 463
+#
+# test OFD locks, F_OFD_SETLK/F_OFD_GETLK
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2017 Red Hat Inc.  All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#-----------------------------------------------------------------------
+#
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# Modify as appropriate.
+_supported_fs generic
+_supported_os Linux
+_require_scratch
+_require_test_program "t_ofd_locks"
+_require_scratch_fcntl_ofd_locks
+
+# real QA test starts here
+_scratch_mkfs >> $seqres.full 2>&1
+
+# prepare a 4k test file
+$XFS_IO_PROG -f -c "pwrite -S 0xFF 0 4096" \
+	$SCRATCH_MNT/testfile >> $seqres.full 2>&1
+
+function do_test()
+{
+	# set_rw : 1 <--> set wrlck
+	#          0 <--> set rdlck
+	local set_rw=$1
+
+	# get_rw : 1 <--> get wrlck
+	#          0 <--> get rdlck
+	local get_rw=$2
+
+	#  start : l_start to getlk
+	local start=$3
+
+	#     rw : 1 <--> open file RDWR
+	#          0 <--> open file RDONLY
+	local rw=$4
+
+	#     rs : expected getlk return value
+	#          1 <--> lock can be placed
+	#          2 <--> get conflict rdlck
+	#          3 <--> get conflict wrlck
+	local rs=$5
+
+	# setlk and wait
+	src/t_ofd_locks $SCRATCH_MNT/testfile 1 $set_rw $start $rw &
+	# check the lock, we've set lock range as [0,9]
+	if ! grep -qE "OFD.*0 *9" /proc/locks ; then
+		echo setlk failed $*
+		wait
+		return
+	fi
+	# getlk
+	src/t_ofd_locks $SCRATCH_MNT/testfile 0 $get_rw $start $rw
+	ret=$?
+	echo $ret >> $seqres.full
+	# checking return value
+	[ $ret -ne $rs ] && echo $ret fail $*
+
+	wait
+}
+
+# Always setlk at range [0,9], getlk at range [0,9] or [20,29]
+# To open file RDONLY or RDWR should not break the locks.
+
+# setlk wrlck [0,9], getlk wrlck [0,9], expect wrlck
+do_test 1 1 0 1 3
+# setlk wrlck [0,9], getlk wrlck [20,29], expect unlck
+do_test 1 1 20 1 1
+# setlk wrlck [0,9], getlk rdlck [0,9], expect wrlck
+do_test 1 0 0 1 3
+# setlk wrlck [0,9], getlk rdlck [20,29], expect unlck
+do_test 1 0 20 1 1
+# setlk rdlck [0,9], getlk wrlck [0,9], expect rdlck
+do_test 0 1 0 0 2
+do_test 0 1 0 1 2
+# setlk rdlck [0,9], getlk wrlck [20,29], expect unlck
+do_test 0 1 20 0 1
+do_test 0 1 20 1 1
+# setlk rdlck [0,9], getlk rdlck [0,9], expect unlck
+do_test 0 0 0 0 1
+do_test 0 0 0 1 1
+# setlk rdlck [0,9], getlk rdlck [0,9], expect unlck
+do_test 0 0 20 0 1
+do_test 0 0 20 1 1
+
+# success, all done
+echo "Silence is golden"
+status=0
+exit
diff --git a/tests/generic/463.out b/tests/generic/463.out
new file mode 100644
index 0000000..dd61371
--- /dev/null
+++ b/tests/generic/463.out
@@ -0,0 +1,2 @@
+QA output created by 463
+Silence is golden
diff --git a/tests/generic/group b/tests/generic/group
index f2a6cda..9031e84 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -465,3 +465,4 @@
 460 auto quick rw
 461 auto shutdown stress
 462 auto quick dax
+463 auto quick
-- 
1.8.3.1