new file mode 100644
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+TEST_GEN_PROGS := ofdlocks
+
+include ../lib.mk
new file mode 100644
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <assert.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include "../kselftest.h"
+
+static int lock_set(int fd, struct flock *fl)
+{
+ int ret;
+
+ fl->l_pid = 0; // needed for OFD locks
+ fl->l_whence = SEEK_SET;
+ ret = fcntl(fd, F_OFD_SETLK, fl);
+ if (ret)
+ perror("fcntl()");
+ return ret;
+}
+
+static int lock_get(int fd, struct flock *fl)
+{
+ int ret;
+
+ fl->l_pid = 0; // needed for OFD locks
+ fl->l_whence = SEEK_SET;
+ ret = fcntl(fd, F_OFD_GETLK, fl);
+ if (ret)
+ perror("fcntl()");
+ return ret;
+}
+
+int main(void)
+{
+ int rc;
+ struct flock fl, fl2;
+ int fd = open("/tmp/aa", O_RDWR | O_CREAT | O_EXCL, 0600);
+ int fd2 = open("/tmp/aa", O_RDONLY);
+
+ unlink("aa");
+ assert(fd != -1);
+ assert(fd2 != -1);
+ ksft_print_msg("[INFO] opened fds %i %i\n", fd, fd2);
+
+ /* Set some read lock */
+ fl.l_type = F_RDLCK;
+ fl.l_start = 5;
+ fl.l_len = 3;
+ rc = lock_set(fd, &fl);
+ if (rc == 0) {
+ ksft_print_msg
+ ("[SUCCESS] set OFD read lock on first fd\n");
+ } else {
+ ksft_print_msg("[FAIL] to set OFD read lock on first fd\n");
+ return -1;
+ }
+ /* Make sure read locks do not conflict on different fds. */
+ fl.l_type = F_RDLCK;
+ fl.l_start = 5;
+ fl.l_len = 1;
+ rc = lock_get(fd2, &fl);
+ if (rc != 0)
+ return -1;
+ if (fl.l_type != F_UNLCK) {
+ ksft_print_msg("[FAIL] read locks conflicted\n");
+ return -1;
+ }
+ /* Make sure read/write locks do conflict on different fds. */
+ fl.l_type = F_WRLCK;
+ fl.l_start = 5;
+ fl.l_len = 1;
+ rc = lock_get(fd2, &fl);
+ if (rc != 0)
+ return -1;
+ if (fl.l_type != F_UNLCK) {
+ ksft_print_msg
+ ("[SUCCESS] read and write locks conflicted\n");
+ } else {
+ ksft_print_msg
+ ("[SUCCESS] read and write locks not conflicted\n");
+ return -1;
+ }
+ /* Get info about the lock on first fd. */
+ fl.l_type = F_UNLCK;
+ fl.l_start = 5;
+ fl.l_len = 1;
+ rc = lock_get(fd, &fl);
+ if (rc != 0) {
+ ksft_print_msg
+ ("[FAIL] F_OFD_GETLK with F_UNLCK not supported\n");
+ return -1;
+ }
+ if (fl.l_type != F_UNLCK) {
+ ksft_print_msg
+ ("[SUCCESS] F_UNLCK test returns: locked, type %i pid %i len %zi\n",
+ fl.l_type, fl.l_pid, fl.l_len);
+ } else {
+ ksft_print_msg
+ ("[FAIL] F_OFD_GETLK with F_UNLCK did not return lock info\n");
+ return -1;
+ }
+ /* Try the same but by locking everything by len==0. */
+ fl2.l_type = F_UNLCK;
+ fl2.l_start = 0;
+ fl2.l_len = 0;
+ rc = lock_get(fd, &fl2);
+ if (rc != 0) {
+ ksft_print_msg
+ ("[FAIL] F_OFD_GETLK with F_UNLCK not supported\n");
+ return -1;
+ }
+ if (memcmp(&fl, &fl2, sizeof(fl))) {
+ ksft_print_msg
+ ("[FAIL] F_UNLCK test returns: locked, type %i pid %i len %zi\n",
+ fl.l_type, fl.l_pid, fl.l_len);
+ return -1;
+ }
+ ksft_print_msg("[SUCCESS] F_UNLCK with len==0 returned the same\n");
+ /* Get info about the lock on second fd - no locks on it. */
+ fl.l_type = F_UNLCK;
+ fl.l_start = 0;
+ fl.l_len = 0;
+ lock_get(fd2, &fl);
+ if (fl.l_type != F_UNLCK) {
+ ksft_print_msg
+ ("[FAIL] F_OFD_GETLK with F_UNLCK return lock info from another fd\n");
+ return -1;
+ }
+ return 0;
+}
Test the basic locking stuff on 2 fds: multiple read locks, conflicts between read and write locks, use of len==0 for queries. Also tests for F_UNLCK F_OFD_GETLK extension. Signed-off-by: Stas Sergeev <stsp2@yandex.ru> CC: Jeff Layton <jlayton@kernel.org> CC: Chuck Lever <chuck.lever@oracle.com> CC: Alexander Viro <viro@zeniv.linux.org.uk> CC: Christian Brauner <brauner@kernel.org> CC: linux-fsdevel@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: Shuah Khan <shuah@kernel.org> CC: linux-kselftest@vger.kernel.org CC: linux-api@vger.kernel.org --- tools/testing/selftests/filelock/Makefile | 5 + tools/testing/selftests/filelock/ofdlocks.c | 132 ++++++++++++++++++++ 2 files changed, 137 insertions(+) create mode 100644 tools/testing/selftests/filelock/Makefile create mode 100644 tools/testing/selftests/filelock/ofdlocks.c