[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;
	struct path	root;
	struct file	*file;
	struct inode	*inode; /* path.dentry.d_inode */
	unsigned int	flags;
	unsigned	seq;
	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 components" flag
 *  - dentry cache is untrusted; force a real lookup
 */
#define LOOKUP_FOLLOW		0x0001
#define LOOKUP_DIRECTORY	0x0002
#define LOOKUP_CONTINUE		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

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

#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 int path_lookup(const char *, unsigned, struct nameidata *);
extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
			   const char *, unsigned int, struct nameidata *);

extern struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
		int (*open)(struct inode *, struct file *));

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

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
	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	20	struct qstr last;
2a737871	21	struct path root;
31e6b01f NP	22	struct file *file;
31e6b01f NP	23	struct inode inode; / path.dentry.d_inode */
1da177e4	24	unsigned int flags;
31e6b01f	25	unsigned seq;
1da177e4 LT	26	int last_type;
	27	unsigned depth;
	28	char *saved_names[MAX_NESTED_LINKS + 1];
	29
	30	/* Intent data */
	31	union {
	32	struct open_intent open;
	33	} intent;
	34	};
	35
	36	/*
	37	* Type of the last component on LOOKUP_PARENT
	38	*/
	39	enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
	40
	41	/*
	42	* The bitmask for a lookup event:
	43	* - follow links at the end
	44	* - require a directory
	45	* - ending slashes ok even for nonexistent files
47a0dfaa	46	* - internal "there are more path components" flag
1da177e4 LT	47	* - dentry cache is untrusted; force a real lookup
1da177e4 LT	48	*/
31e6b01f NP	49	#define LOOKUP_FOLLOW 0x0001
	50	#define LOOKUP_DIRECTORY 0x0002
	51	#define LOOKUP_CONTINUE 0x0004
	52
	53	#define LOOKUP_PARENT 0x0010
	54	#define LOOKUP_REVAL 0x0020
	55	#define LOOKUP_RCU 0x0040
1da177e4 LT	56	/*
	57	* Intent data
	58	*/
3516586a AV	59	#define LOOKUP_OPEN 0x0100
	60	#define LOOKUP_CREATE 0x0200
	61	#define LOOKUP_EXCL 0x0400
4e9ed2f8	62	#define LOOKUP_RENAME_TARGET 0x0800
1da177e4	63
2d8f3038 AV	64	extern int user_path_at(int, const char __user , unsigned, struct path );
	65
	66	#define user_path(name, path) user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW, path)
	67	#define user_lpath(name, path) user_path_at(AT_FDCWD, name, 0, path)
	68	#define user_path_dir(name, path) \
	69	user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW \| LOOKUP_DIRECTORY, path)
	70
d1811465 AV	71	extern int kern_path(const char , unsigned, struct path );
d1811465 AV	72
b3c97528	73	extern int path_lookup(const char , unsigned, struct nameidata );
16f18200 JJS	74	extern int vfs_path_lookup(struct dentry , struct vfsmount ,
16f18200 JJS	75	const char , unsigned int, struct nameidata );
1da177e4	76
834f2a4a TM	77	extern struct file lookup_instantiate_filp(struct nameidata nd, struct dentry *dentry,
834f2a4a TM	78	int (open)(struct inode , struct file *));
834f2a4a	79
eead1911	80	extern struct dentry lookup_one_len(const char , struct dentry *, int);
1da177e4	81
9393bd07	82	extern int follow_down(struct path *);
bab77ebf	83	extern int follow_up(struct path *);
1da177e4 LT	84
	85	extern struct dentry lock_rename(struct dentry , struct dentry *);
	86	extern void unlock_rename(struct dentry , struct dentry );
	87
	88	static inline void nd_set_link(struct nameidata nd, char path)
	89	{
	90	nd->saved_names[nd->depth] = path;
	91	}
	92
	93	static inline char nd_get_link(struct nameidata nd)
	94	{
	95	return nd->saved_names[nd->depth];
	96	}
	97
03514685 DG	98	static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
	99	{
	100	((char *) name)[min(len, maxlen)] = '\0';
	101	}
	102
1da177e4	103	#endif /* _LINUX_NAMEI_H */