Unverified Commit be1ca3ee authored by Christian Brauner's avatar Christian Brauner
Browse files

selftests/statmount: add statmount_alloc() helper 

Add a helper to allocate a statmount buffer and call statmount(). This
helper will be shared by multiple test suites that need to query mount
information via statmount().

Link: https://patch.msgid.link/20260122-work-fsmount-namespace-v1-5-5ef0a886e646@kernel.org


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent fc1a05de

tools/testing/selftests/filesystems/open_tree_ns/open_tree_ns_test.c

+4 −4
Original line number Diff line number Diff line
@@ -115,7 +115,7 @@ static void dump_mounts(struct __test_metadata *_metadata, uint64_t mnt_ns_id) 
				     STATMOUNT_MNT_BASIC |

				     STATMOUNT_FS_TYPE |

				     STATMOUNT_MNT_ROOT |

				     STATMOUNT_MNT_POINT);

				     STATMOUNT_MNT_POINT, 0);

		if (!sm) {

			TH_LOG("  [%zd] mnt_id %llu: statmount failed: %s",

			       i, (unsigned long long)list[i], strerror(errno));
@@ -746,7 +746,7 @@ TEST_F(open_tree_ns_userns, umount_fails_einval) 
			const char *mnt_point;



			sm = statmount_alloc(list[i], new_ns_id,

					     STATMOUNT_MNT_POINT);

					     STATMOUNT_MNT_POINT, 0);

			if (!sm)

				_exit(11);
@@ -863,7 +863,7 @@ TEST_F(open_tree_ns_userns, umount_succeeds) 
			const char *mnt_point;



			sm = statmount_alloc(list[i], new_ns_id,

					     STATMOUNT_MNT_POINT);

					     STATMOUNT_MNT_POINT, 0);

			if (!sm)

				_exit(11);
@@ -1003,7 +1003,7 @@ TEST_F(open_tree_ns_unbindable, recursive_skips_on_unbindable) 
		struct statmount *sm;

		const char *mnt_point;



		sm = statmount_alloc(list[i], new_ns_id, STATMOUNT_MNT_POINT);

		sm = statmount_alloc(list[i], new_ns_id, STATMOUNT_MNT_POINT, 0);

		ASSERT_NE(sm, NULL) {

			TH_LOG("statmount_alloc failed for mnt_id %llu",

			       (unsigned long long)list[i]);

tools/testing/selftests/filesystems/statmount/statmount.h

+51 −0
Original line number Diff line number Diff line
@@ -3,10 +3,14 @@ 
#ifndef __STATMOUNT_H

#define __STATMOUNT_H



#include <errno.h>

#include <stdint.h>

#include <stdlib.h>

#include <linux/mount.h>

#include <asm/unistd.h>



#define STATMOUNT_BUFSIZE (1 << 15)



#ifndef __NR_statmount

	#if defined __alpha__

		#define __NR_statmount 567
@@ -84,4 +88,51 @@ static inline ssize_t listmount(uint64_t mnt_id, uint64_t mnt_ns_id, 
	return syscall(__NR_listmount, &req, list, num, flags);

}



static inline struct statmount *statmount_alloc(uint64_t mnt_id, uint64_t mnt_ns_id,

						 uint64_t mask, unsigned int flags)

{

	struct statmount *buf;

	size_t bufsize = STATMOUNT_BUFSIZE;

	int ret;



	for (;;) {

		buf = malloc(bufsize);

		if (!buf)

			return NULL;



		ret = statmount(mnt_id, mnt_ns_id, 0, mask, buf, bufsize, flags);

		if (ret == 0)

			return buf;



		free(buf);

		if (errno != EOVERFLOW)

			return NULL;



		bufsize <<= 1;

	}

}



static inline struct statmount *statmount_alloc_by_fd(int fd, uint64_t mask)

{

	struct statmount *buf;

	size_t bufsize = STATMOUNT_BUFSIZE;

	int ret;



	for (;;) {

		buf = malloc(bufsize);

		if (!buf)

			return NULL;



		ret = statmount(0, 0, fd, mask, buf, bufsize, STATMOUNT_BY_FD);

		if (ret == 0)

			return buf;



		free(buf);

		if (errno != EOVERFLOW)

			return NULL;



		bufsize <<= 1;

	}

}



#endif /* __STATMOUNT_H */

tools/testing/selftests/filesystems/statmount/statmount_test.c

+3 −42
Original line number Diff line number Diff line
@@ -33,45 +33,6 @@ static const char *const known_fs[] = { 
	"sysv", "tmpfs", "tracefs", "ubifs", "udf", "ufs", "v7", "vboxsf",

	"vfat", "virtiofs", "vxfs", "xenfs", "xfs", "zonefs", NULL };



static struct statmount *statmount_alloc(uint64_t mnt_id, int fd, uint64_t mask, unsigned int flags)

{

	size_t bufsize = 1 << 15;

	struct statmount *buf = NULL, *tmp = NULL;

	int tofree = 0;

	int ret;



	if (flags & STATMOUNT_BY_FD && fd < 0)

		return NULL;



	tmp = alloca(bufsize);



	for (;;) {

		if (flags & STATMOUNT_BY_FD)

			ret = statmount(0, 0, (uint32_t) fd, mask, tmp, bufsize, flags);

		else

			ret = statmount(mnt_id, 0, 0, mask, tmp, bufsize, flags);



		if (ret != -1)

			break;

		if (tofree)

			free(tmp);

		if (errno != EOVERFLOW)

			return NULL;

		bufsize <<= 1;

		tofree = 1;

		tmp = malloc(bufsize);

		if (!tmp)

			return NULL;

	}

	buf = malloc(tmp->size);

	if (buf)

		memcpy(buf, tmp, tmp->size);

	if (tofree)

		free(tmp);



	return buf;

}



static void write_file(const char *path, const char *val)

{

	int fd = open(path, O_WRONLY);
@@ -715,7 +676,7 @@ static void test_statmount_by_fd(void) 
		goto err_fd;

	}



	sm = statmount_alloc(0, fd, STATMOUNT_MNT_ROOT | STATMOUNT_MNT_POINT, STATMOUNT_BY_FD);

	sm = statmount_alloc_by_fd(fd, STATMOUNT_MNT_ROOT | STATMOUNT_MNT_POINT);

	if (!sm) {

		ksft_test_result_fail("statmount by fd failed: %s\n", strerror(errno));

		goto err_chroot;
@@ -750,7 +711,7 @@ static void test_statmount_by_fd(void) 
	}



	free(sm);

	sm = statmount_alloc(0, fd, STATMOUNT_MNT_ROOT | STATMOUNT_MNT_POINT, STATMOUNT_BY_FD);

	sm = statmount_alloc_by_fd(fd, STATMOUNT_MNT_ROOT | STATMOUNT_MNT_POINT);

	if (!sm) {

		ksft_test_result_fail("statmount by fd failed: %s\n", strerror(errno));

		goto err_fd;
@@ -844,7 +805,7 @@ static void test_statmount_by_fd_unmounted(void) 
		goto err_fd;

	}



	sm = statmount_alloc(0, fd, STATMOUNT_MNT_POINT | STATMOUNT_MNT_ROOT, STATMOUNT_BY_FD);

	sm = statmount_alloc_by_fd(fd, STATMOUNT_MNT_POINT | STATMOUNT_MNT_ROOT);

	if (!sm) {

		ksft_test_result_fail("statmount by fd unmounted: %s\n",

				      strerror(errno));