tmp_suning_uos_patched/include/linux/namei.h
Trond Myklebust 834f2a4a15 VFS: Allow the filesystem to return a full file pointer on open intent
This is needed by NFSv4 for atomicity reasons: our open command is in
 fact a lookup+open, so we need to be able to propagate open context
 information from lookup() into the resulting struct file's
 private_data field.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-10-18 14:20:16 -07:00

96 lines
2.7 KiB
C

#ifndef _LINUX_NAMEI_H
#define _LINUX_NAMEI_H
#include <linux/linkage.h>
struct vfsmount;
struct open_intent {
int flags;
int create_mode;
struct file *file;
};
enum { MAX_NESTED_LINKS = 5 };
struct nameidata {
struct dentry *dentry;
struct vfsmount *mnt;
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)
extern int FASTCALL(__user_walk(const char __user *, unsigned, struct nameidata *));
#define user_path_walk(name,nd) \
__user_walk(name, LOOKUP_FOLLOW, nd)
#define user_path_walk_link(name,nd) \
__user_walk(name, 0, nd)
extern int FASTCALL(path_lookup(const char *, unsigned, struct nameidata *));
extern int FASTCALL(path_walk(const char *, struct nameidata *));
extern int FASTCALL(link_path_walk(const char *, struct nameidata *));
extern void path_release(struct nameidata *);
extern void path_release_on_umount(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(const char *, 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_hash(struct qstr *, 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 */