blktests: New loop tests

Add test for setting partscan flag.

Signed-off-by Jan Kara <[email protected]>

---
 src/Makefile                   |  3 ++-
 src/loop_set_status_partscan.c | 45 ++++++++++++++++++++++++++++++++++++++++++
 tests/loop/006                 | 33 +++++++++++++++++++++++++++++++
 tests/loop/006.out             |  2 ++
 4 files changed, 82 insertions(+), 1 deletion(-)
 create mode 100644 src/loop_set_status_partscan.c
 create mode 100755 tests/loop/006
 create mode 100644 tests/loop/006.out

src/Makefile +2 -1

index f89f61701179..6dadcbec8beb 100644
@@ -4,7 +4,8 @@ C_TARGETS := \
 	openclose \
 	sg/dxfer-from-dev \
 	sg/syzkaller1 \
-	nbdsetsize
+	nbdsetsize \
+	loop_set_status_partscan
 
 CXX_TARGETS := \
 	discontiguous-io

src/loop_set_status_partscan.c new file +25 -0

new file mode 100644
index 000000000000..8873a12e4334
@@ -0,0 +1,45 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <linux/loop.h>
+
+void usage(const char *progname)
+{
+	fprintf(stderr, "usage: %s PATH\n", progname);
+	exit(EXIT_FAILURE);
+}
+
+int main(int argc, char **argv)
+{
+	int ret;
+	int fd;
+	struct loop_info64 info;
+
+	if (argc != 2)
+		usage(argv[0]);

src/loop_set_status_partscan.c new file +9 -0

+	ret = ioctl(fd, LOOP_SET_STATUS64, &info);
+	if (ret == -1) {
+		perror("ioctl");
+		close(fd);
+		return EXIT_FAILURE;
+	}
+	close(fd);
+	return EXIT_SUCCESS;
+}

Quoted 3 lines · Jan Kara

Add test for setting partscan flag.

Signed-off-by Jan Kara <[email protected]>

Sorry I didn't notice this earlier, but loop/001 already does a partition rescan (via losetup -P). Does that cover this test case?

Quoted 12 lines

src/loop_set_status_partscan.c new file +12 -0

+int main(int argc, char **argv)
+{
+	int ret;
+	int fd;
+	struct loop_info64 info;
+
+	if (argc != 2)
+		usage(argv[0]);
+
+	fd = open(argv[1], O_RDONLY);
+	if (fd == -1) {
+		perror("open");

src/loop_set_status_partscan.c line 35

Quoted 6 lines

src/loop_set_status_partscan.c new file +6 -0

+		return EXIT_FAILURE;
+	}
+
+	memset(&info, 0, sizeof(info));
+	info.lo_flags = LO_FLAGS_PARTSCAN;
+	memcpy(info.lo_file_name, "part", 5);

What's the significance of this file name?

Quoted 3 lines · Omar Sandoval

Quoted 2 lines · Jan Kara

Add test for setting partscan flag.

Quoted 4 lines

Quoted 1 line

Signed-off-by Jan Kara <[email protected]>

Sorry I didn't notice this earlier, but loop/001 already does a partition rescan (via losetup -P). Does that cover this test case?

Yes I know. But the partition rescanning on device creation has been handled properly while partition rescanning as a result of LOOP_SET_STATUS was buggy. That's why I've added this test.

Quoted 4 lines · Jan Kara

Quoted 3 lines · Omar Sandoval

Quoted 2 lines · Jan Kara

Add test for setting partscan flag.

Quoted 8 lines

Quoted 4 lines

Quoted 1 line

Signed-off-by Jan Kara <[email protected]>

Sorry I didn't notice this earlier, but loop/001 already does a partition rescan (via losetup -P). Does that cover this test case?

Yes I know. But the partition rescanning on device creation has been handled properly while partition rescanning as a result of LOOP_SET_STATUS was buggy. That's why I've added this test.

At least here, losetup -P does a LOOP_SET_STATUS:

$ sudo strace -e ioctl losetup -f --show -P test.img
ioctl(3, LOOP_CTL_GET_FREE)             = 0
ioctl(4, LOOP_SET_FD, 3)                = 0
ioctl(4, LOOP_SET_STATUS64, {lo_offset=0, lo_number=0, lo_flags=LO_FLAGS_PARTSCAN, lo_file_name="/home/osandov/test.img", ...}) = 0
/dev/loop0
+++ exited with 0 +++

Add regression test for patch "block/loop: Use global lock for ioctl() operation." where we can oops while traversing list of loop devices backing newly created device.

Signed-off-by Jan Kara <[email protected]>

Hello,

these two patches create two new tests for blktests as regression tests for my recently posted loopback device fixes. More details in individual patches.