linux-stable/include/linux/namei.h
David Howells 6f45b65672 Add an AT_NO_AUTOMOUNT flag to suppress terminal automount
Add an AT_NO_AUTOMOUNT flag to suppress terminal automounting of automount
point directories.  This can be used by fstatat() users to permit the
gathering of attributes on an automount point and also prevent
mass-automounting of a directory of automount points by ls.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15 20:07:33 -05:00

106 lines
2.7 KiB
C

#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
* - suppress terminal automount
*/
#define LOOKUP_FOLLOW 0x0001
#define LOOKUP_DIRECTORY 0x0002
#define LOOKUP_CONTINUE 0x0004
#define LOOKUP_PARENT 0x0010
#define LOOKUP_REVAL 0x0020
#define LOOKUP_RCU 0x0040
#define LOOKUP_NO_AUTOMOUNT 0x0080
/*
* 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_one(struct path *);
extern int follow_down(struct path *, bool);
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 */