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

#ifndef _LINUX_NAMEI_H
#define _LINUX_NAMEI_H

#include <linux/dcache.h>
#include <linux/linkage.h>
#include <linux/path.h>

struct vfsmount;

struct open_intent {
	int	flags;
	int	create_mode;
	struct file *file;
};

enum { MAX_NESTED_LINKS = 8 };

struct nameidata {
	struct path	path;
	struct qstr	last;
	unsigned int	flags;
	int		last_type;
	unsigned	depth;
	char *saved_names[MAX_NESTED_LINKS + 1];

	/* Intent data */
	union {
		struct open_intent open;
	} intent;
};

/*
 * Type of the last component on LOOKUP_PARENT
 */
enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};

/*
 * The bitmask for a lookup event:
 *  - follow links at the end
 *  - require a directory
 *  - ending slashes ok even for nonexistent files
 *  - internal "there are more path compnents" flag
 *  - locked when lookup done with dcache_lock held
 *  - dentry cache is untrusted; force a real lookup
 */
#define LOOKUP_FOLLOW		 1
#define LOOKUP_DIRECTORY	 2
#define LOOKUP_CONTINUE		 4
#define LOOKUP_PARENT		16
#define LOOKUP_NOALT		32
#define LOOKUP_REVAL		64
/*
 * Intent data
 */
#define LOOKUP_OPEN		(0x0100)
#define LOOKUP_CREATE		(0x0200)
#define LOOKUP_ACCESS		(0x0400)
#define LOOKUP_CHDIR		(0x0800)

extern int __user_walk(const char __user *, unsigned, struct nameidata *);
extern int __user_walk_fd(int dfd, const char __user *, unsigned, struct nameidata *);
#define user_path_walk(name,nd) \
	__user_walk_fd(AT_FDCWD, name, LOOKUP_FOLLOW, nd)
#define user_path_walk_link(name,nd) \
	__user_walk_fd(AT_FDCWD, name, 0, nd)
extern int path_lookup(const char *, unsigned, struct nameidata *);
extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
			   const char *, unsigned int, struct nameidata *);

extern int __user_path_lookup_open(const char __user *, unsigned lookup_flags, struct nameidata *nd, int open_flags);
extern int path_lookup_open(int dfd, const char *name, unsigned lookup_flags, struct nameidata *, int open_flags);
extern struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
		int (*open)(struct inode *, struct file *));
extern struct file *nameidata_to_filp(struct nameidata *nd, int flags);
extern void release_open_intent(struct nameidata *);

extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
extern struct dentry *lookup_one_noperm(const char *, struct dentry *);

extern int follow_down(struct vfsmount **, struct dentry **);
extern int follow_up(struct vfsmount **, struct dentry **);

extern struct dentry *lock_rename(struct dentry *, struct dentry *);
extern void unlock_rename(struct dentry *, struct dentry *);

static inline void nd_set_link(struct nameidata *nd, char *path)
{
	nd->saved_names[nd->depth] = path;
}

static inline char *nd_get_link(struct nameidata *nd)
{
	return nd->saved_names[nd->depth];
}

#endif /* _LINUX_NAMEI_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_NAMEI_H
	2	#define _LINUX_NAMEI_H
	3
82b0547c	4	#include <linux/dcache.h>
1da177e4	5	#include <linux/linkage.h>
c5e725f3	6	#include <linux/path.h>
1da177e4 LT	7
	8	struct vfsmount;
	9
	10	struct open_intent {
	11	int flags;
	12	int create_mode;
834f2a4a	13	struct file *file;
1da177e4 LT	14	};
1da177e4 LT	15
737bebd1	16	enum { MAX_NESTED_LINKS = 8 };
1da177e4 LT	17
1da177e4 LT	18	struct nameidata {
4ac91378	19	struct path path;
1da177e4 LT	20	struct qstr last;
	21	unsigned int flags;
	22	int last_type;
	23	unsigned depth;
	24	char *saved_names[MAX_NESTED_LINKS + 1];
	25
	26	/* Intent data */
	27	union {
	28	struct open_intent open;
	29	} intent;
	30	};
	31
	32	/*
	33	* Type of the last component on LOOKUP_PARENT
	34	*/
	35	enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
	36
	37	/*
	38	* The bitmask for a lookup event:
	39	* - follow links at the end
	40	* - require a directory
	41	* - ending slashes ok even for nonexistent files
	42	* - internal "there are more path compnents" flag
	43	* - locked when lookup done with dcache_lock held
	44	* - dentry cache is untrusted; force a real lookup
	45	*/
	46	#define LOOKUP_FOLLOW 1
	47	#define LOOKUP_DIRECTORY 2
	48	#define LOOKUP_CONTINUE 4
	49	#define LOOKUP_PARENT 16
	50	#define LOOKUP_NOALT 32
	51	#define LOOKUP_REVAL 64
	52	/*
	53	* Intent data
	54	*/
	55	#define LOOKUP_OPEN (0x0100)
	56	#define LOOKUP_CREATE (0x0200)
	57	#define LOOKUP_ACCESS (0x0400)
650a8983	58	#define LOOKUP_CHDIR (0x0800)
1da177e4	59
b3c97528 HH	60	extern int __user_walk(const char __user , unsigned, struct nameidata );
b3c97528 HH	61	extern int __user_walk_fd(int dfd, const char __user , unsigned, struct nameidata );
1da177e4	62	#define user_path_walk(name,nd) \
5590ff0d	63	__user_walk_fd(AT_FDCWD, name, LOOKUP_FOLLOW, nd)
1da177e4	64	#define user_path_walk_link(name,nd) \
5590ff0d	65	__user_walk_fd(AT_FDCWD, name, 0, nd)
b3c97528	66	extern int path_lookup(const char , unsigned, struct nameidata );
16f18200 JJS	67	extern int vfs_path_lookup(struct dentry , struct vfsmount ,
16f18200 JJS	68	const char , unsigned int, struct nameidata );
1da177e4	69
834f2a4a	70	extern int __user_path_lookup_open(const char __user , unsigned lookup_flags, struct nameidata nd, int open_flags);
5590ff0d	71	extern int path_lookup_open(int dfd, const char name, unsigned lookup_flags, struct nameidata , int open_flags);
834f2a4a TM	72	extern struct file lookup_instantiate_filp(struct nameidata nd, struct dentry *dentry,
	73	int (open)(struct inode , struct file *));
	74	extern struct file nameidata_to_filp(struct nameidata nd, int flags);
	75	extern void release_open_intent(struct nameidata *);
	76
eead1911 CH	77	extern struct dentry lookup_one_len(const char , struct dentry *, int);
eead1911 CH	78	extern struct dentry lookup_one_noperm(const char , struct dentry *);
1da177e4 LT	79
	80	extern int follow_down(struct vfsmount , struct dentry );
	81	extern int follow_up(struct vfsmount , struct dentry );
	82
	83	extern struct dentry lock_rename(struct dentry , struct dentry *);
	84	extern void unlock_rename(struct dentry , struct dentry );
	85
	86	static inline void nd_set_link(struct nameidata nd, char path)
	87	{
	88	nd->saved_names[nd->depth] = path;
	89	}
	90
	91	static inline char nd_get_link(struct nameidata nd)
	92	{
	93	return nd->saved_names[nd->depth];
	94	}
	95
	96	#endif /* _LINUX_NAMEI_H */