samples/vfs: use shared header

Share some infrastructure between sample programs and fix a build
failure that was reported.

Reported-by: Sasha Levin <[e-mail]>
Link: https://lore.kernel.org/r/Z42UkSXx0MS9qZ9w@lappy
Link: https://qa-reports.linaro.org/lkft/sashal-linus-next/build/v6.13-rc7-511-g109a8e0fa9d6/testrun/26809210/suite/build/test/gcc-8-allyesconfig/log
Signed-off-by: Christian Brauner <[e-mail]>

samples/vfs/mountinfo.c

···
 #define __SANE_USERSPACE_TYPES__
 #include <stdio.h>
 #include <stdint.h>
-#include <sys/ioctl.h>
-#include <sys/syscall.h>
-#include <linux/pidfd.h>
-#include <linux/mount.h>
-#include <linux/nsfs.h>
 #include <unistd.h>
 #include <alloca.h>
 #include <getopt.h>
 #include <stdlib.h>
 #include <stdbool.h>
 #include <errno.h>
+
+#include "samples-vfs.h"
 
 /* max mounts per listmount call */
 #define MAXMOUNTS		1024
···
 #define STATMOUNT_BUFSIZE	4096
 
 static bool ext_format;
+
+#ifndef __NR_pidfd_open
+#define __NR_pidfd_open -1
+#endif
 
 /*
  * There are no bindings in glibc for listmount() and statmount() (yet),
···
 	}
 
 	/* Get a pidfd for pid */
-	pidfd = syscall(SYS_pidfd_open, pid, 0);
+	pidfd = syscall(__NR_pidfd_open, pid, 0);
 	if (pidfd < 0) {
 		perror("pidfd_open");
 		return 1;

samples/vfs/samples-vfs.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __SAMPLES_VFS_H
+#define __SAMPLES_VFS_H
+
+#include <errno.h>
+#include <linux/types.h>
+#include <sys/ioctl.h>
+#include <sys/syscall.h>
+
+#define die_errno(format, ...)                                             \
+	do {                                                               \
+		fprintf(stderr, "%m | %s: %d: %s: " format "\n", __FILE__, \
+			__LINE__, __func__, ##__VA_ARGS__);                \
+		exit(EXIT_FAILURE);                                        \
+	} while (0)
+
+struct statmount {
+	__u32 size;		/* Total size, including strings */
+	__u32 mnt_opts;		/* [str] Options (comma separated, escaped) */
+	__u64 mask;		/* What results were written */
+	__u32 sb_dev_major;	/* Device ID */
+	__u32 sb_dev_minor;
+	__u64 sb_magic;		/* ..._SUPER_MAGIC */
+	__u32 sb_flags;		/* SB_{RDONLY,SYNCHRONOUS,DIRSYNC,LAZYTIME} */
+	__u32 fs_type;		/* [str] Filesystem type */
+	__u64 mnt_id;		/* Unique ID of mount */
+	__u64 mnt_parent_id;	/* Unique ID of parent (for root == mnt_id) */
+	__u32 mnt_id_old;	/* Reused IDs used in proc/.../mountinfo */
+	__u32 mnt_parent_id_old;
+	__u64 mnt_attr;		/* MOUNT_ATTR_... */
+	__u64 mnt_propagation;	/* MS_{SHARED,SLAVE,PRIVATE,UNBINDABLE} */
+	__u64 mnt_peer_group;	/* ID of shared peer group */
+	__u64 mnt_master;	/* Mount receives propagation from this ID */
+	__u64 propagate_from;	/* Propagation from in current namespace */
+	__u32 mnt_root;		/* [str] Root of mount relative to root of fs */
+	__u32 mnt_point;	/* [str] Mountpoint relative to current root */
+	__u64 mnt_ns_id;	/* ID of the mount namespace */
+	__u32 fs_subtype;	/* [str] Subtype of fs_type (if any) */
+	__u32 sb_source;	/* [str] Source string of the mount */
+	__u32 opt_num;		/* Number of fs options */
+	__u32 opt_array;	/* [str] Array of nul terminated fs options */
+	__u32 opt_sec_num;	/* Number of security options */
+	__u32 opt_sec_array;	/* [str] Array of nul terminated security options */
+	__u64 __spare2[46];
+	char str[];		/* Variable size part containing strings */
+};
+
+struct mnt_id_req {
+	__u32 size;
+	__u32 spare;
+	__u64 mnt_id;
+	__u64 param;
+	__u64 mnt_ns_id;
+};
+
+#ifndef MNT_ID_REQ_SIZE_VER0
+#define MNT_ID_REQ_SIZE_VER0	24 /* sizeof first published struct */
+#endif
+
+#ifndef MNT_ID_REQ_SIZE_VER1
+#define MNT_ID_REQ_SIZE_VER1	32 /* sizeof second published struct */
+#endif
+
+/* Get the id for a mount namespace */
+#ifndef NS_GET_MNTNS_ID
+#define NS_GET_MNTNS_ID _IO(0xb7, 0x5)
+#endif
+
+struct mnt_ns_info {
+	__u32 size;
+	__u32 nr_mounts;
+	__u64 mnt_ns_id;
+};
+
+#ifndef MNT_NS_INFO_SIZE_VER0
+#define MNT_NS_INFO_SIZE_VER0 16 /* size of first published struct */
+#endif
+
+#ifndef NS_MNT_GET_INFO
+#define NS_MNT_GET_INFO _IOR(0xb7, 10, struct mnt_ns_info)
+#endif
+
+#ifndef NS_MNT_GET_NEXT
+#define NS_MNT_GET_NEXT _IOR(0xb7, 11, struct mnt_ns_info)
+#endif
+
+#ifndef NS_MNT_GET_PREV
+#define NS_MNT_GET_PREV _IOR(0xb7, 12, struct mnt_ns_info)
+#endif
+
+#ifndef PIDFD_GET_MNT_NAMESPACE
+#define PIDFD_GET_MNT_NAMESPACE _IO(0xFF, 3)
+#endif
+
+#ifndef __NR_listmount
+#define __NR_listmount 458
+#endif
+
+#ifndef __NR_statmount
+#define __NR_statmount 457
+#endif
+
+#ifndef LSMT_ROOT
+#define LSMT_ROOT		0xffffffffffffffff	/* root mount */
+#endif
+
+/* @mask bits for statmount(2) */
+#ifndef STATMOUNT_SB_BASIC
+#define STATMOUNT_SB_BASIC		0x00000001U /* Want/got sb_... */
+#endif
+
+#ifndef STATMOUNT_MNT_BASIC
+#define STATMOUNT_MNT_BASIC		0x00000002U /* Want/got mnt_... */
+#endif
+
+#ifndef STATMOUNT_PROPAGATE_FROM
+#define STATMOUNT_PROPAGATE_FROM	0x00000004U /* Want/got propagate_from */
+#endif
+
+#ifndef STATMOUNT_MNT_ROOT
+#define STATMOUNT_MNT_ROOT		0x00000008U /* Want/got mnt_root  */
+#endif
+
+#ifndef STATMOUNT_MNT_POINT
+#define STATMOUNT_MNT_POINT		0x00000010U /* Want/got mnt_point */
+#endif
+
+#ifndef STATMOUNT_FS_TYPE
+#define STATMOUNT_FS_TYPE		0x00000020U /* Want/got fs_type */
+#endif
+
+#ifndef STATMOUNT_MNT_NS_ID
+#define STATMOUNT_MNT_NS_ID		0x00000040U /* Want/got mnt_ns_id */
+#endif
+
+#ifndef STATMOUNT_MNT_OPTS
+#define STATMOUNT_MNT_OPTS		0x00000080U /* Want/got mnt_opts */
+#endif
+
+#ifndef STATMOUNT_FS_SUBTYPE
+#define STATMOUNT_FS_SUBTYPE		0x00000100U /* Want/got fs_subtype */
+#endif
+
+#ifndef STATMOUNT_SB_SOURCE
+#define STATMOUNT_SB_SOURCE		0x00000200U /* Want/got sb_source */
+#endif
+
+#ifndef STATMOUNT_OPT_ARRAY
+#define STATMOUNT_OPT_ARRAY		0x00000400U /* Want/got opt_... */
+#endif
+
+#ifndef STATMOUNT_OPT_SEC_ARRAY
+#define STATMOUNT_OPT_SEC_ARRAY		0x00000800U /* Want/got opt_sec... */
+#endif
+
+#ifndef STATX_MNT_ID_UNIQUE
+#define STATX_MNT_ID_UNIQUE 0x00004000U /* Want/got extended stx_mount_id */
+#endif
+
+#ifndef MOUNT_ATTR_RDONLY
+#define MOUNT_ATTR_RDONLY	0x00000001 /* Mount read-only */
+#endif
+
+#ifndef MOUNT_ATTR_NOSUID
+#define MOUNT_ATTR_NOSUID	0x00000002 /* Ignore suid and sgid bits */
+#endif
+
+#ifndef MOUNT_ATTR_NODEV
+#define MOUNT_ATTR_NODEV	0x00000004 /* Disallow access to device special files */
+#endif
+
+#ifndef MOUNT_ATTR_NOEXEC
+#define MOUNT_ATTR_NOEXEC	0x00000008 /* Disallow program execution */
+#endif
+
+#ifndef MOUNT_ATTR__ATIME
+#define MOUNT_ATTR__ATIME	0x00000070 /* Setting on how atime should be updated */
+#endif
+
+#ifndef MOUNT_ATTR_RELATIME
+#define MOUNT_ATTR_RELATIME	0x00000000 /* - Update atime relative to mtime/ctime. */
+#endif
+
+#ifndef MOUNT_ATTR_NOATIME
+#define MOUNT_ATTR_NOATIME	0x00000010 /* - Do not update access times. */
+#endif
+
+#ifndef MOUNT_ATTR_STRICTATIME
+#define MOUNT_ATTR_STRICTATIME	0x00000020 /* - Always perform atime updates */
+#endif
+
+#ifndef MOUNT_ATTR_NODIRATIME
+#define MOUNT_ATTR_NODIRATIME	0x00000080 /* Do not update directory access times */
+#endif
+
+#ifndef MOUNT_ATTR_IDMAP
+#define MOUNT_ATTR_IDMAP	0x00100000 /* Idmap mount to @userns_fd in struct mount_attr. */
+#endif
+
+#ifndef MOUNT_ATTR_NOSYMFOLLOW
+#define MOUNT_ATTR_NOSYMFOLLOW	0x00200000 /* Do not follow symlinks */
+#endif
+
+#ifndef MS_RDONLY
+#define MS_RDONLY	 1	/* Mount read-only */
+#endif
+
+#ifndef MS_SYNCHRONOUS
+#define MS_SYNCHRONOUS	16	/* Writes are synced at once */
+#endif
+
+#ifndef MS_MANDLOCK
+#define MS_MANDLOCK	64	/* Allow mandatory locks on an FS */
+#endif
+
+#ifndef MS_DIRSYNC
+#define MS_DIRSYNC	128	/* Directory modifications are synchronous */
+#endif
+
+#ifndef MS_UNBINDABLE
+#define MS_UNBINDABLE	(1<<17)	/* change to unbindable */
+#endif
+
+#ifndef MS_PRIVATE
+#define MS_PRIVATE	(1<<18)	/* change to private */
+#endif
+
+#ifndef MS_SLAVE
+#define MS_SLAVE	(1<<19)	/* change to slave */
+#endif
+
+#ifndef MS_SHARED
+#define MS_SHARED	(1<<20)	/* change to shared */
+#endif
+
+#ifndef MS_LAZYTIME
+#define MS_LAZYTIME	(1<<25) /* Update the on-disk [acm]times lazily */
+#endif
+
+#endif /* __SAMPLES_VFS_H */

samples/vfs/test-list-all-mounts.c

···
 #include <limits.h>
 #include <linux/types.h>
 #include <stdio.h>
-#include <sys/ioctl.h>
-#include <sys/syscall.h>
 
 #include "../../tools/testing/selftests/pidfd/pidfd.h"
-
-#define die_errno(format, ...)                                             \
-	do {                                                               \
-		fprintf(stderr, "%m | %s: %d: %s: " format "\n", __FILE__, \
-			__LINE__, __func__, ##__VA_ARGS__);                \
-		exit(EXIT_FAILURE);                                        \
-	} while (0)
-
-/* Get the id for a mount namespace */
-#define NS_GET_MNTNS_ID _IO(0xb7, 0x5)
-/* Get next mount namespace. */
-
-struct mnt_ns_info {
-	__u32 size;
-	__u32 nr_mounts;
-	__u64 mnt_ns_id;
-};
-
-#define MNT_NS_INFO_SIZE_VER0 16 /* size of first published struct */
-
-/* Get information about namespace. */
-#define NS_MNT_GET_INFO _IOR(0xb7, 10, struct mnt_ns_info)
-/* Get next namespace. */
-#define NS_MNT_GET_NEXT _IOR(0xb7, 11, struct mnt_ns_info)
-/* Get previous namespace. */
-#define NS_MNT_GET_PREV _IOR(0xb7, 12, struct mnt_ns_info)
-
-#define PIDFD_GET_MNT_NAMESPACE _IO(0xFF, 3)
-
-#ifndef __NR_listmount
-#define __NR_listmount 458
-#endif
-
-#ifndef __NR_statmount
-#define __NR_statmount 457
-#endif
-
-/* @mask bits for statmount(2) */
-#define STATMOUNT_SB_BASIC		0x00000001U /* Want/got sb_... */
-#define STATMOUNT_MNT_BASIC		0x00000002U /* Want/got mnt_... */
-#define STATMOUNT_PROPAGATE_FROM	0x00000004U /* Want/got propagate_from */
-#define STATMOUNT_MNT_ROOT		0x00000008U /* Want/got mnt_root  */
-#define STATMOUNT_MNT_POINT		0x00000010U /* Want/got mnt_point */
-#define STATMOUNT_FS_TYPE		0x00000020U /* Want/got fs_type */
-#define STATMOUNT_MNT_NS_ID		0x00000040U /* Want/got mnt_ns_id */
-#define STATMOUNT_MNT_OPTS		0x00000080U /* Want/got mnt_opts */
-
-#define STATX_MNT_ID_UNIQUE 0x00004000U /* Want/got extended stx_mount_id */
-
-struct statmount {
-	__u32 size;
-	__u32 mnt_opts;
-	__u64 mask;
-	__u32 sb_dev_major;
-	__u32 sb_dev_minor;
-	__u64 sb_magic;
-	__u32 sb_flags;
-	__u32 fs_type;
-	__u64 mnt_id;
-	__u64 mnt_parent_id;
-	__u32 mnt_id_old;
-	__u32 mnt_parent_id_old;
-	__u64 mnt_attr;
-	__u64 mnt_propagation;
-	__u64 mnt_peer_group;
-	__u64 mnt_master;
-	__u64 propagate_from;
-	__u32 mnt_root;
-	__u32 mnt_point;
-	__u64 mnt_ns_id;
-	__u64 __spare2[49];
-	char str[];
-};
-
-struct mnt_id_req {
-	__u32 size;
-	__u32 spare;
-	__u64 mnt_id;
-	__u64 param;
-	__u64 mnt_ns_id;
-};
-
-#define MNT_ID_REQ_SIZE_VER1 32 /* sizeof second published struct */
-
-#define LSMT_ROOT 0xffffffffffffffff /* root mount */
+#include "samples-vfs.h"
 
 static int __statmount(__u64 mnt_id, __u64 mnt_ns_id, __u64 mask,
 		       struct statmount *stmnt, size_t bufsize,