linux_dsm_epyc7002/include/linux/mount.h
Al Viro 8f2918898e new helpers: vfs_create_mount(), fc_mount()
Create a new helper, vfs_create_mount(), that creates a detached vfsmount
object from an fs_context that has a superblock attached to it.

Almost all uses will be paired with immediately preceding vfs_get_tree();
add a helper for such combination.

Switch vfs_kern_mount() to use this.

NOTE: mild behaviour change; passing NULL as 'device name' to
something like procfs will change /proc/*/mountstats - "device none"
instead on "no device".  That is consistent with /proc/mounts et.al.

[do'h - EXPORT_SYMBOL_GPL slipped in by mistake; removed]
[AV -- remove confused comment from vfs_create_mount()]
[AV -- removed the second argument]

Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-01-30 17:44:24 -05:00

111 lines
3.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
*
* Definitions for mount interface. This describes the in the kernel build
* linkedlist with mounted filesystems.
*
* Author: Marco van Wieringen <mvw@planets.elm.net>
*
*/
#ifndef _LINUX_MOUNT_H
#define _LINUX_MOUNT_H
#include <linux/types.h>
#include <linux/list.h>
#include <linux/nodemask.h>
#include <linux/spinlock.h>
#include <linux/seqlock.h>
#include <linux/atomic.h>
struct super_block;
struct vfsmount;
struct dentry;
struct mnt_namespace;
struct fs_context;
#define MNT_NOSUID 0x01
#define MNT_NODEV 0x02
#define MNT_NOEXEC 0x04
#define MNT_NOATIME 0x08
#define MNT_NODIRATIME 0x10
#define MNT_RELATIME 0x20
#define MNT_READONLY 0x40 /* does the user want this to be r/o? */
#define MNT_SHRINKABLE 0x100
#define MNT_WRITE_HOLD 0x200
#define MNT_SHARED 0x1000 /* if the vfsmount is a shared mount */
#define MNT_UNBINDABLE 0x2000 /* if the vfsmount is a unbindable mount */
/*
* MNT_SHARED_MASK is the set of flags that should be cleared when a
* mount becomes shared. Currently, this is only the flag that says a
* mount cannot be bind mounted, since this is how we create a mount
* that shares events with another mount. If you add a new MNT_*
* flag, consider how it interacts with shared mounts.
*/
#define MNT_SHARED_MASK (MNT_UNBINDABLE)
#define MNT_USER_SETTABLE_MASK (MNT_NOSUID | MNT_NODEV | MNT_NOEXEC \
| MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME \
| MNT_READONLY)
#define MNT_ATIME_MASK (MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME )
#define MNT_INTERNAL_FLAGS (MNT_SHARED | MNT_WRITE_HOLD | MNT_INTERNAL | \
MNT_DOOMED | MNT_SYNC_UMOUNT | MNT_MARKED)
#define MNT_INTERNAL 0x4000
#define MNT_LOCK_ATIME 0x040000
#define MNT_LOCK_NOEXEC 0x080000
#define MNT_LOCK_NOSUID 0x100000
#define MNT_LOCK_NODEV 0x200000
#define MNT_LOCK_READONLY 0x400000
#define MNT_LOCKED 0x800000
#define MNT_DOOMED 0x1000000
#define MNT_SYNC_UMOUNT 0x2000000
#define MNT_MARKED 0x4000000
#define MNT_UMOUNT 0x8000000
struct vfsmount {
struct dentry *mnt_root; /* root of the mounted tree */
struct super_block *mnt_sb; /* pointer to superblock */
int mnt_flags;
} __randomize_layout;
struct file; /* forward dec */
struct path;
extern int mnt_want_write(struct vfsmount *mnt);
extern int mnt_want_write_file(struct file *file);
extern int mnt_clone_write(struct vfsmount *mnt);
extern void mnt_drop_write(struct vfsmount *mnt);
extern void mnt_drop_write_file(struct file *file);
extern void mntput(struct vfsmount *mnt);
extern struct vfsmount *mntget(struct vfsmount *mnt);
extern struct vfsmount *mnt_clone_internal(const struct path *path);
extern bool __mnt_is_readonly(struct vfsmount *mnt);
extern bool mnt_may_suid(struct vfsmount *mnt);
struct path;
extern struct vfsmount *clone_private_mount(const struct path *path);
struct file_system_type;
extern struct vfsmount *fc_mount(struct fs_context *fc);
extern struct vfsmount *vfs_create_mount(struct fs_context *fc);
extern struct vfsmount *vfs_kern_mount(struct file_system_type *type,
int flags, const char *name,
void *data);
extern struct vfsmount *vfs_submount(const struct dentry *mountpoint,
struct file_system_type *type,
const char *name, void *data);
extern void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list);
extern void mark_mounts_for_expiry(struct list_head *mounts);
extern dev_t name_to_dev_t(const char *name);
extern unsigned int sysctl_mount_max;
extern bool path_is_mountpoint(const struct path *path);
#endif /* _LINUX_MOUNT_H */