4 #include <linux/kernel.h>
5 #include <linux/path.h>
6 #include <linux/fcntl.h>
7 #include <linux/errno.h>
9 enum { MAX_NESTED_LINKS = 8 };
11 #define MAXSYMLINKS 40
14 * Type of the last component on LOOKUP_PARENT
16 enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
19 * The bitmask for a lookup event:
20 * - follow links at the end
21 * - require a directory
22 * - ending slashes ok even for nonexistent files
23 * - internal "there are more path components" flag
24 * - dentry cache is untrusted; force a real lookup
25 * - suppress terminal automount
27 #define LOOKUP_FOLLOW 0x0001
28 #define LOOKUP_DIRECTORY 0x0002
29 #define LOOKUP_AUTOMOUNT 0x0004
31 #define LOOKUP_PARENT 0x0010
32 #define LOOKUP_REVAL 0x0020
33 #define LOOKUP_RCU 0x0040
34 #define LOOKUP_NO_REVAL 0x0080
39 #define LOOKUP_OPEN 0x0100
40 #define LOOKUP_CREATE 0x0200
41 #define LOOKUP_EXCL 0x0400
42 #define LOOKUP_RENAME_TARGET 0x0800
44 #define LOOKUP_JUMPED 0x1000
45 #define LOOKUP_ROOT 0x2000
46 #define LOOKUP_EMPTY 0x4000
48 extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);
50 static inline int user_path_at(int dfd, const char __user *name, unsigned flags,
53 return user_path_at_empty(dfd, name, flags, path, NULL);
56 static inline int user_path(const char __user *name, struct path *path)
58 return user_path_at_empty(AT_FDCWD, name, LOOKUP_FOLLOW, path, NULL);
61 static inline int user_lpath(const char __user *name, struct path *path)
63 return user_path_at_empty(AT_FDCWD, name, 0, path, NULL);
66 static inline int user_path_dir(const char __user *name, struct path *path)
68 return user_path_at_empty(AT_FDCWD, name,
69 LOOKUP_FOLLOW | LOOKUP_DIRECTORY, path, NULL);
72 extern int kern_path(const char *, unsigned, struct path *);
74 extern struct dentry *kern_path_create(int, const char *, struct path *, unsigned int);
75 extern struct dentry *user_path_create(int, const char __user *, struct path *, unsigned int);
76 extern void done_path_create(struct path *, struct dentry *);
77 extern struct dentry *kern_path_locked(const char *, struct path *);
78 extern int kern_path_mountpoint(int, const char *, struct path *, unsigned int);
80 extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
81 extern struct dentry *lookup_one_len_unlocked(const char *, struct dentry *, int);
83 extern int follow_down_one(struct path *);
84 extern int follow_down(struct path *);
85 extern int follow_up(struct path *);
87 extern struct dentry *lock_rename(struct dentry *, struct dentry *);
88 extern void unlock_rename(struct dentry *, struct dentry *);
90 extern void nd_jump_link(struct path *path);
92 static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
94 ((char *) name)[min(len, maxlen)] = '\0';
98 * retry_estale - determine whether the caller should retry an operation
99 * @error: the error that would currently be returned
100 * @flags: flags being used for next lookup attempt
102 * Check to see if the error code was -ESTALE, and then determine whether
103 * to retry the call based on whether "flags" already has LOOKUP_REVAL set.
105 * Returns true if the caller should try the operation again.
108 retry_estale(const long error, const unsigned int flags)
110 return error == -ESTALE && !(flags & LOOKUP_REVAL);
113 #endif /* _LINUX_NAMEI_H */