mirror of
https://github.com/torvalds/linux.git
synced 2026-04-18 14:53:58 -04:00
be1ca3ee8f
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: Christian Brauner <brauner@kernel.org>
139 lines
2.8 KiB
C
139 lines
2.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
#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
|
|
#elif defined _MIPS_SIM
|
|
#if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */
|
|
#define __NR_statmount 4457
|
|
#endif
|
|
#if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */
|
|
#define __NR_statmount 6457
|
|
#endif
|
|
#if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */
|
|
#define __NR_statmount 5457
|
|
#endif
|
|
#else
|
|
#define __NR_statmount 457
|
|
#endif
|
|
#endif
|
|
|
|
#ifndef __NR_listmount
|
|
#if defined __alpha__
|
|
#define __NR_listmount 568
|
|
#elif defined _MIPS_SIM
|
|
#if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */
|
|
#define __NR_listmount 4458
|
|
#endif
|
|
#if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */
|
|
#define __NR_listmount 6458
|
|
#endif
|
|
#if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */
|
|
#define __NR_listmount 5458
|
|
#endif
|
|
#else
|
|
#define __NR_listmount 458
|
|
#endif
|
|
#endif
|
|
|
|
static inline int statmount(uint64_t mnt_id, uint64_t mnt_ns_id, uint32_t fd,
|
|
uint64_t mask, struct statmount *buf, size_t bufsize,
|
|
unsigned int flags)
|
|
{
|
|
struct mnt_id_req req = {
|
|
.size = MNT_ID_REQ_SIZE_VER0,
|
|
.param = mask,
|
|
};
|
|
|
|
if (flags & STATMOUNT_BY_FD) {
|
|
req.size = MNT_ID_REQ_SIZE_VER1;
|
|
req.mnt_fd = fd;
|
|
} else {
|
|
req.mnt_id = mnt_id;
|
|
if (mnt_ns_id) {
|
|
req.size = MNT_ID_REQ_SIZE_VER1;
|
|
req.mnt_ns_id = mnt_ns_id;
|
|
}
|
|
}
|
|
|
|
return syscall(__NR_statmount, &req, buf, bufsize, flags);
|
|
}
|
|
|
|
static inline ssize_t listmount(uint64_t mnt_id, uint64_t mnt_ns_id,
|
|
uint64_t last_mnt_id, uint64_t list[], size_t num,
|
|
unsigned int flags)
|
|
{
|
|
struct mnt_id_req req = {
|
|
.size = MNT_ID_REQ_SIZE_VER0,
|
|
.mnt_id = mnt_id,
|
|
.param = last_mnt_id,
|
|
};
|
|
|
|
if (mnt_ns_id) {
|
|
req.size = MNT_ID_REQ_SIZE_VER1;
|
|
req.mnt_ns_id = 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 */
|