[mirror_ubuntu-bionic-kernel.git] / include / linux / mount.h

/*
 *
 * Definitions for mount interface. This describes the in the kernel build 
 * linkedlist with mounted filesystems.
 *
 * Author:  Marco van Wieringen <mvw@planets.elm.net>
 *
 * Version: $Id: mount.h,v 2.0 1996/11/17 16:48:14 mvw Exp mvw $
 *
 */
#ifndef _LINUX_MOUNT_H
#define _LINUX_MOUNT_H
#ifdef __KERNEL__

#include <linux/types.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <asm/atomic.h>

struct super_block;
struct vfsmount;
struct dentry;
struct mnt_namespace;

#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_SHRINKABLE	0x100

#define MNT_SHARED	0x1000	/* if the vfsmount is a shared mount */
#define MNT_UNBINDABLE	0x2000	/* if the vfsmount is a unbindable mount */
#define MNT_PNODE_MASK	0x3000	/* propagation flag mask */

struct vfsmount {
	struct list_head mnt_hash;
	struct vfsmount *mnt_parent;	/* fs we are mounted on */
	struct dentry *mnt_mountpoint;	/* dentry of mountpoint */
	struct dentry *mnt_root;	/* root of the mounted tree */
	struct super_block *mnt_sb;	/* pointer to superblock */
	struct list_head mnt_mounts;	/* list of children, anchored here */
	struct list_head mnt_child;	/* and going through their mnt_child */
	int mnt_flags;
	/* 4 bytes hole on 64bits arches */
	char *mnt_devname;		/* Name of device e.g. /dev/dsk/hda1 */
	struct list_head mnt_list;
	struct list_head mnt_expire;	/* link in fs-specific expiry list */
	struct list_head mnt_share;	/* circular list of shared mounts */
	struct list_head mnt_slave_list;/* list of slave mounts */
	struct list_head mnt_slave;	/* slave list entry */
	struct vfsmount *mnt_master;	/* slave is on master->mnt_slave_list */
	struct mnt_namespace *mnt_ns;	/* containing namespace */
	/*
	 * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount
	 * to let these frequently modified fields in a separate cache line
	 * (so that reads of mnt_flags wont ping-pong on SMP machines)
	 */
	atomic_t mnt_count;
	int mnt_expiry_mark;		/* true if marked for expiry */
	int mnt_pinned;
	int mnt_ghosts;
};

static inline struct vfsmount *mntget(struct vfsmount *mnt)
{
	if (mnt)
		atomic_inc(&mnt->mnt_count);
	return mnt;
}

extern void mntput_no_expire(struct vfsmount *mnt);
extern void mnt_pin(struct vfsmount *mnt);
extern void mnt_unpin(struct vfsmount *mnt);

static inline void mntput(struct vfsmount *mnt)
{
	if (mnt) {
		mnt->mnt_expiry_mark = 0;
		mntput_no_expire(mnt);
	}
}

extern void free_vfsmnt(struct vfsmount *mnt);
extern struct vfsmount *alloc_vfsmnt(const char *name);
extern struct vfsmount *do_kern_mount(const char *fstype, int flags,
				      const char *name, void *data);

struct file_system_type;
extern struct vfsmount *vfs_kern_mount(struct file_system_type *type,
				      int flags, const char *name,
				      void *data);

struct nameidata;

extern int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd,
			int mnt_flags, struct list_head *fslist);

extern void mark_mounts_for_expiry(struct list_head *mounts);

extern spinlock_t vfsmount_lock;
extern dev_t name_to_dev_t(char *name);

#endif
#endif /* _LINUX_MOUNT_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	*
	3	* Definitions for mount interface. This describes the in the kernel build
	4	* linkedlist with mounted filesystems.
	5	*
	6	* Author: Marco van Wieringen <mvw@planets.elm.net>
	7	*
	8	* Version: $Id: mount.h,v 2.0 1996/11/17 16:48:14 mvw Exp mvw $
	9	*
	10	*/
	11	#ifndef _LINUX_MOUNT_H
	12	#define _LINUX_MOUNT_H
	13	#ifdef __KERNEL__
	14
d53d9f16	15	#include <linux/types.h>
1da177e4 LT	16	#include <linux/list.h>
	17	#include <linux/spinlock.h>
	18	#include <asm/atomic.h>
	19
726c3342 DH	20	struct super_block;
	21	struct vfsmount;
	22	struct dentry;
6b3286ed	23	struct mnt_namespace;
726c3342	24
07b20889 RP	25	#define MNT_NOSUID 0x01
	26	#define MNT_NODEV 0x02
	27	#define MNT_NOEXEC 0x04
fc33a7bb CH	28	#define MNT_NOATIME 0x08
fc33a7bb CH	29	#define MNT_NODIRATIME 0x10
47ae32d6	30	#define MNT_RELATIME 0x20
bf066c7d	31
5528f911 TM	32	#define MNT_SHRINKABLE 0x100
5528f911 TM	33
fc33a7bb CH	34	#define MNT_SHARED 0x1000 /* if the vfsmount is a shared mount */
fc33a7bb CH	35	#define MNT_UNBINDABLE 0x2000 /* if the vfsmount is a unbindable mount */
beb7dd86	36	#define MNT_PNODE_MASK 0x3000 /* propagation flag mask */
1da177e4	37
07b20889	38	struct vfsmount {
1da177e4 LT	39	struct list_head mnt_hash;
	40	struct vfsmount mnt_parent; / fs we are mounted on */
	41	struct dentry mnt_mountpoint; / dentry of mountpoint */
	42	struct dentry mnt_root; / root of the mounted tree */
	43	struct super_block mnt_sb; / pointer to superblock */
	44	struct list_head mnt_mounts; /* list of children, anchored here */
	45	struct list_head mnt_child; /* and going through their mnt_child */
1da177e4	46	int mnt_flags;
4ba4d4c0	47	/* 4 bytes hole on 64bits arches */
1da177e4 LT	48	char mnt_devname; / Name of device e.g. /dev/dsk/hda1 */
1da177e4 LT	49	struct list_head mnt_list;
55e700b9	50	struct list_head mnt_expire; /* link in fs-specific expiry list */
03e06e68	51	struct list_head mnt_share; /* circular list of shared mounts */
a58b0eb8 RP	52	struct list_head mnt_slave_list;/* list of slave mounts */
	53	struct list_head mnt_slave; /* slave list entry */
	54	struct vfsmount mnt_master; / slave is on master->mnt_slave_list */
6b3286ed	55	struct mnt_namespace mnt_ns; / containing namespace */
4ba4d4c0 ED	56	/*
	57	* We put mnt_count & mnt_expiry_mark at the end of struct vfsmount
	58	* to let these frequently modified fields in a separate cache line
	59	* (so that reads of mnt_flags wont ping-pong on SMP machines)
	60	*/
	61	atomic_t mnt_count;
	62	int mnt_expiry_mark; /* true if marked for expiry */
7b7b1ace	63	int mnt_pinned;
7c4b93d8	64	int mnt_ghosts;
1da177e4 LT	65	};
	66
	67	static inline struct vfsmount mntget(struct vfsmount mnt)
	68	{
	69	if (mnt)
	70	atomic_inc(&mnt->mnt_count);
	71	return mnt;
	72	}
	73
7b7b1ace AV	74	extern void mntput_no_expire(struct vfsmount *mnt);
	75	extern void mnt_pin(struct vfsmount *mnt);
	76	extern void mnt_unpin(struct vfsmount *mnt);
1da177e4 LT	77
	78	static inline void mntput(struct vfsmount *mnt)
	79	{
	80	if (mnt) {
	81	mnt->mnt_expiry_mark = 0;
751c404b	82	mntput_no_expire(mnt);
1da177e4 LT	83	}
	84	}
	85
	86	extern void free_vfsmnt(struct vfsmount *mnt);
	87	extern struct vfsmount alloc_vfsmnt(const char name);
	88	extern struct vfsmount do_kern_mount(const char fstype, int flags,
	89	const char name, void data);
	90
bb4a58bf TM	91	struct file_system_type;
	92	extern struct vfsmount vfs_kern_mount(struct file_system_type type,
	93	int flags, const char *name,
	94	void *data);
	95
1da177e4 LT	96	struct nameidata;
	97
	98	extern int do_add_mount(struct vfsmount newmnt, struct nameidata nd,
	99	int mnt_flags, struct list_head *fslist);
	100
	101	extern void mark_mounts_for_expiry(struct list_head *mounts);
	102
	103	extern spinlock_t vfsmount_lock;
d53d9f16	104	extern dev_t name_to_dev_t(char *name);
1da177e4 LT	105
	106	#endif
	107	#endif /* _LINUX_MOUNT_H */