[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;

enum { MAX_NESTED_LINKS = 8 };

struct nameidata {
	struct path	path;
	struct qstr	last;
	struct path	root;
	struct inode	*inode; /* path.dentry.d_inode */
	unsigned int	flags;
	unsigned	seq;
	int		last_type;
	unsigned	depth;
	char *saved_names[MAX_NESTED_LINKS + 1];
};

/*
 * 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 components" flag
 *  - dentry cache is untrusted; force a real lookup
 *  - suppress terminal automount
 */
#define LOOKUP_FOLLOW		0x0001
#define LOOKUP_DIRECTORY	0x0002
#define LOOKUP_AUTOMOUNT	0x0004

#define LOOKUP_PARENT		0x0010
#define LOOKUP_REVAL		0x0020
#define LOOKUP_RCU		0x0040

/*
 * Intent data
 */
#define LOOKUP_OPEN		0x0100
#define LOOKUP_CREATE		0x0200
#define LOOKUP_EXCL		0x0400
#define LOOKUP_RENAME_TARGET	0x0800

#define LOOKUP_JUMPED		0x1000
#define LOOKUP_ROOT		0x2000
#define LOOKUP_EMPTY		0x4000

extern int user_path_at(int, const char __user *, unsigned, struct path *);
extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);

#define user_path(name, path) user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW, path)
#define user_lpath(name, path) user_path_at(AT_FDCWD, name, 0, path)
#define user_path_dir(name, path) \
	user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, path)

extern int kern_path(const char *, unsigned, struct path *);

extern struct dentry *kern_path_create(int, const char *, struct path *, int);
extern struct dentry *user_path_create(int, const char __user *, struct path *, int);
extern int kern_path_parent(const char *, struct nameidata *);
extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
			   const char *, unsigned int, struct path *);

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

extern int follow_down_one(struct path *);
extern int follow_down(struct path *);
extern int follow_up(struct path *);

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];
}

static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
{
	((char *) name)[min(len, maxlen)] = '\0';
}

#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
737bebd1	10	enum { MAX_NESTED_LINKS = 8 };
1da177e4 LT	11
1da177e4 LT	12	struct nameidata {
4ac91378	13	struct path path;
1da177e4	14	struct qstr last;
2a737871	15	struct path root;
31e6b01f	16	struct inode inode; / path.dentry.d_inode */
1da177e4	17	unsigned int flags;
31e6b01f	18	unsigned seq;
1da177e4 LT	19	int last_type;
	20	unsigned depth;
	21	char *saved_names[MAX_NESTED_LINKS + 1];
1da177e4 LT	22	};
	23
	24	/*
	25	* Type of the last component on LOOKUP_PARENT
	26	*/
	27	enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
	28
	29	/*
	30	* The bitmask for a lookup event:
	31	* - follow links at the end
	32	* - require a directory
	33	* - ending slashes ok even for nonexistent files
47a0dfaa	34	* - internal "there are more path components" flag
1da177e4	35	* - dentry cache is untrusted; force a real lookup
6f45b656	36	* - suppress terminal automount
1da177e4	37	*/
31e6b01f NP	38	#define LOOKUP_FOLLOW 0x0001
31e6b01f NP	39	#define LOOKUP_DIRECTORY 0x0002
d94c177b	40	#define LOOKUP_AUTOMOUNT 0x0004
31e6b01f NP	41
	42	#define LOOKUP_PARENT 0x0010
	43	#define LOOKUP_REVAL 0x0020
	44	#define LOOKUP_RCU 0x0040
b6c8069d	45
1da177e4 LT	46	/*
	47	* Intent data
	48	*/
3516586a AV	49	#define LOOKUP_OPEN 0x0100
	50	#define LOOKUP_CREATE 0x0200
	51	#define LOOKUP_EXCL 0x0400
4e9ed2f8	52	#define LOOKUP_RENAME_TARGET 0x0800
1da177e4	53
16c2cd71	54	#define LOOKUP_JUMPED 0x1000
5b6ca027	55	#define LOOKUP_ROOT 0x2000
f52e0c11	56	#define LOOKUP_EMPTY 0x4000
16c2cd71	57
2d8f3038	58	extern int user_path_at(int, const char __user , unsigned, struct path );
1fa1e7f6	59	extern int user_path_at_empty(int, const char __user , unsigned, struct path , int *empty);
2d8f3038 AV	60
	61	#define user_path(name, path) user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW, path)
	62	#define user_lpath(name, path) user_path_at(AT_FDCWD, name, 0, path)
	63	#define user_path_dir(name, path) \
	64	user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW \| LOOKUP_DIRECTORY, path)
	65
d1811465 AV	66	extern int kern_path(const char , unsigned, struct path );
d1811465 AV	67
dae6ad8f AV	68	extern struct dentry kern_path_create(int, const char , struct path *, int);
dae6ad8f AV	69	extern struct dentry user_path_create(int, const char __user , struct path *, int);
c9c6cac0	70	extern int kern_path_parent(const char , struct nameidata );
16f18200	71	extern int vfs_path_lookup(struct dentry , struct vfsmount ,
e0a01249	72	const char , unsigned int, struct path );
1da177e4	73
eead1911	74	extern struct dentry lookup_one_len(const char , struct dentry *, int);
1da177e4	75
cc53ce53	76	extern int follow_down_one(struct path *);
7cc90cc3	77	extern int follow_down(struct path *);
bab77ebf	78	extern int follow_up(struct path *);
1da177e4 LT	79
	80	extern struct dentry lock_rename(struct dentry , struct dentry *);
	81	extern void unlock_rename(struct dentry , struct dentry );
	82
	83	static inline void nd_set_link(struct nameidata nd, char path)
	84	{
	85	nd->saved_names[nd->depth] = path;
	86	}
	87
	88	static inline char nd_get_link(struct nameidata nd)
	89	{
	90	return nd->saved_names[nd->depth];
	91	}
	92
03514685 DG	93	static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
	94	{
	95	((char *) name)[min(len, maxlen)] = '\0';
	96	}
	97
1da177e4	98	#endif /* _LINUX_NAMEI_H */