Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1#ifndef _LINUX_NAMEI_H
2#define _LINUX_NAMEI_H
3
4#include <linux/dcache.h>
5#include <linux/linkage.h>
6#include <linux/path.h>
7
8struct vfsmount;
9
10struct open_intent {
11 int flags;
12 int create_mode;
13 struct file *file;
14};
15
16enum { MAX_NESTED_LINKS = 8 };
17
18struct nameidata {
19 struct path path;
20 struct qstr last;
21 struct path root;
22 unsigned int flags;
23 int last_type;
24 unsigned depth;
25 char *saved_names[MAX_NESTED_LINKS + 1];
26
27 /* Intent data */
28 union {
29 struct open_intent open;
30 } intent;
31};
32
33/*
34 * Type of the last component on LOOKUP_PARENT
35 */
36enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
37
38/*
39 * The bitmask for a lookup event:
40 * - follow links at the end
41 * - require a directory
42 * - ending slashes ok even for nonexistent files
43 * - internal "there are more path components" flag
44 * - locked when lookup done with dcache_lock held
45 * - dentry cache is untrusted; force a real lookup
46 */
47#define LOOKUP_FOLLOW 1
48#define LOOKUP_DIRECTORY 2
49#define LOOKUP_CONTINUE 4
50#define LOOKUP_PARENT 16
51#define LOOKUP_REVAL 64
52/*
53 * Intent data
54 */
55#define LOOKUP_OPEN 0x0100
56#define LOOKUP_CREATE 0x0200
57#define LOOKUP_EXCL 0x0400
58#define LOOKUP_RENAME_TARGET 0x0800
59
60extern int user_path_at(int, const char __user *, unsigned, struct path *);
61
62#define user_path(name, path) user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW, path)
63#define user_lpath(name, path) user_path_at(AT_FDCWD, name, 0, path)
64#define user_path_dir(name, path) \
65 user_path_at(AT_FDCWD, name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, path)
66
67extern int kern_path(const char *, unsigned, struct path *);
68
69extern int path_lookup(const char *, unsigned, struct nameidata *);
70extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
71 const char *, unsigned int, struct nameidata *);
72
73extern struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
74 int (*open)(struct inode *, struct file *));
75extern struct file *nameidata_to_filp(struct nameidata *nd, int flags);
76extern void release_open_intent(struct nameidata *);
77
78extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
79extern struct dentry *lookup_one_noperm(const char *, struct dentry *);
80
81extern int follow_down(struct path *);
82extern int follow_up(struct path *);
83
84extern struct dentry *lock_rename(struct dentry *, struct dentry *);
85extern void unlock_rename(struct dentry *, struct dentry *);
86
87static inline void nd_set_link(struct nameidata *nd, char *path)
88{
89 nd->saved_names[nd->depth] = path;
90}
91
92static inline char *nd_get_link(struct nameidata *nd)
93{
94 return nd->saved_names[nd->depth];
95}
96
97static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
98{
99 ((char *) name)[min(len, maxlen)] = '\0';
100}
101
102#endif /* _LINUX_NAMEI_H */