include/linux/namei.h

   1 #ifndef _LINUX_NAMEI_H
   2 #define _LINUX_NAMEI_H
   3
   4 #include <linux/linkage.h>
   5
   6 struct vfsmount;
   7
   8 struct open_intent {
   9         int     flags;
  10         int     create_mode;
  11 };
  12
  13 enum { MAX_NESTED_LINKS = 5 };
  14
  15 struct nameidata {
  16         struct dentry   *dentry;
  17         struct vfsmount *mnt;
  18         struct qstr     last;
  19         unsigned int    flags;
  20         int             last_type;
  21         unsigned        depth;
  22         char *saved_names[MAX_NESTED_LINKS + 1];
  23
  24         /* Intent data */
  25         union {
  26                 struct open_intent open;
  27         } intent;
  28 };
  29
  30 /*
  31  * Type of the last component on LOOKUP_PARENT
  32  */
  33 enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
  34
  35 /*
  36  * The bitmask for a lookup event:
  37  *  - follow links at the end
  38  *  - require a directory
  39  *  - ending slashes ok even for nonexistent files
  40  *  - internal "there are more path compnents" flag
  41  *  - locked when lookup done with dcache_lock held
  42  *  - dentry cache is untrusted; force a real lookup
  43  */
  44 #define LOOKUP_FOLLOW            1
  45 #define LOOKUP_DIRECTORY         2
  46 #define LOOKUP_CONTINUE          4
  47 #define LOOKUP_PARENT           16
  48 #define LOOKUP_NOALT            32
  49 #define LOOKUP_REVAL            64
  50 /*
  51  * Intent data
  52  */
  53 #define LOOKUP_OPEN             (0x0100)
  54 #define LOOKUP_CREATE           (0x0200)
  55 #define LOOKUP_ACCESS           (0x0400)
  56
  57 extern int FASTCALL(__user_walk(const char __user *, unsigned, struct nameidata *));
  58 #define user_path_walk(name,nd) \
  59         __user_walk(name, LOOKUP_FOLLOW, nd)
  60 #define user_path_walk_link(name,nd) \
  61         __user_walk(name, 0, nd)
  62 extern int FASTCALL(path_lookup(const char *, unsigned, struct nameidata *));
  63 extern int FASTCALL(path_walk(const char *, struct nameidata *));
  64 extern int FASTCALL(link_path_walk(const char *, struct nameidata *));
  65 extern void path_release(struct nameidata *);
  66 extern void path_release_on_umount(struct nameidata *);
  67
  68 extern struct dentry * lookup_one_len(const char *, struct dentry *, int);
  69 extern struct dentry * lookup_hash(struct qstr *, struct dentry *);
  70
  71 extern int follow_down(struct vfsmount **, struct dentry **);
  72 extern int follow_up(struct vfsmount **, struct dentry **);
  73
  74 extern struct dentry *lock_rename(struct dentry *, struct dentry *);
  75 extern void unlock_rename(struct dentry *, struct dentry *);
  76
  77 static inline void nd_set_link(struct nameidata *nd, char *path)
  78 {
  79         nd->saved_names[nd->depth] = path;
  80 }
  81
  82 static inline char *nd_get_link(struct nameidata *nd)
  83 {
  84         return nd->saved_names[nd->depth];
  85 }
  86
  87 #endif /* _LINUX_NAMEI_H */