linux-stable/include/linux/mount.h
Linus Torvalds 3df88c6a17 Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull ipc namespace update from Al Viro:
 "Rik's patches reducing the amount of synchronize_rcu() triggered by
  ipc namespace destruction.

  I've some pending stuff reducing that on the normal umount side, but
  it's nowhere near ready and Rik's stuff shouldn't be held back due to
  conflicts - I'll just redo the parts of my series that stray into
  ipc/*"

* 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ipc,namespace: batch free ipc_namespace structures
  ipc,namespace: make ipc namespace allocation wait for pending free
2023-02-24 19:20:07 -08:00

127 lines
4.3 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 <asm/barrier.h>
struct super_block;
struct dentry;
struct user_namespace;
struct mnt_idmap;
struct file_system_type;
struct fs_context;
struct file;
struct path;
#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_NOSYMFOLLOW 0x80
#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 | MNT_NOSYMFOLLOW)
#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 | \
MNT_CURSOR)
#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
#define MNT_CURSOR 0x10000000
struct vfsmount {
struct dentry *mnt_root; /* root of the mounted tree */
struct super_block *mnt_sb; /* pointer to superblock */
int mnt_flags;
struct mnt_idmap *mnt_idmap;
} __randomize_layout;
static inline struct mnt_idmap *mnt_idmap(const struct vfsmount *mnt)
{
/* Pairs with smp_store_release() in do_idmap_mount(). */
return smp_load_acquire(&mnt->mnt_idmap);
}
extern int mnt_want_write(struct vfsmount *mnt);
extern int mnt_want_write_file(struct file *file);
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 void mnt_make_shortterm(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);
extern struct vfsmount *clone_private_mount(const struct path *path);
extern int __mnt_want_write(struct vfsmount *);
extern void __mnt_drop_write(struct vfsmount *);
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 bool path_is_mountpoint(const struct path *path);
extern bool our_mnt(struct vfsmount *mnt);
extern struct vfsmount *kern_mount(struct file_system_type *);
extern void kern_unmount(struct vfsmount *mnt);
extern int may_umount_tree(struct vfsmount *);
extern int may_umount(struct vfsmount *);
extern long do_mount(const char *, const char __user *,
const char *, unsigned long, void *);
extern struct vfsmount *collect_mounts(const struct path *);
extern void drop_collected_mounts(struct vfsmount *);
extern int iterate_mounts(int (*)(struct vfsmount *, void *), void *,
struct vfsmount *);
extern void kern_unmount_array(struct vfsmount *mnt[], unsigned int num);
#endif /* _LINUX_MOUNT_H */