include/linux/namei.h
changeset 0 aa628870c1d3
child 2 d1f6d8b6f81c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/linux/namei.h	Sun Jan 11 20:20:11 2009 +0100
@@ -0,0 +1,97 @@
+#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;
+	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_REVAL		64
+/*
+ * 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 int path_lookup_open(int dfd, const char *name, 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_one_noperm(const char *, 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 */