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-rw-r--r--kernel/include/linux/namei.h98
1 files changed, 98 insertions, 0 deletions
diff --git a/kernel/include/linux/namei.h b/kernel/include/linux/namei.h
new file mode 100644
index 000000000..c8990779f
--- /dev/null
+++ b/kernel/include/linux/namei.h
@@ -0,0 +1,98 @@
+#ifndef _LINUX_NAMEI_H
+#define _LINUX_NAMEI_H
+
+#include <linux/dcache.h>
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <linux/path.h>
+
+struct vfsmount;
+struct nameidata;
+
+enum { MAX_NESTED_LINKS = 8 };
+
+/*
+ * 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_AUTOMOUNT 0x0004
+
+#define LOOKUP_PARENT 0x0010
+#define LOOKUP_REVAL 0x0020
+#define LOOKUP_RCU 0x0040
+
+/*
+ * Intent data
+ */
+#define LOOKUP_OPEN 0x0100
+#define LOOKUP_CREATE 0x0200
+#define LOOKUP_EXCL 0x0400
+#define LOOKUP_RENAME_TARGET 0x0800
+
+#define LOOKUP_JUMPED 0x1000
+#define LOOKUP_ROOT 0x2000
+#define LOOKUP_EMPTY 0x4000
+
+extern int user_path_at(int, const char __user *, unsigned, struct path *);
+extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);
+
+#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 struct dentry *kern_path_create(int, const char *, struct path *, unsigned int);
+extern struct dentry *user_path_create(int, const char __user *, struct path *, unsigned int);
+extern void done_path_create(struct path *, struct dentry *);
+extern struct dentry *kern_path_locked(const char *, struct path *);
+extern int kern_path_mountpoint(int, const char *, struct path *, unsigned int);
+
+extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
+
+extern int follow_down_one(struct path *);
+extern int follow_down(struct path *);
+extern int follow_up(struct path *);
+
+extern struct dentry *lock_rename(struct dentry *, struct dentry *);
+extern void unlock_rename(struct dentry *, struct dentry *);
+
+extern void nd_jump_link(struct nameidata *nd, struct path *path);
+extern void nd_set_link(struct nameidata *nd, char *path);
+extern char *nd_get_link(struct nameidata *nd);
+
+static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
+{
+ ((char *) name)[min(len, maxlen)] = '\0';
+}
+
+/**
+ * retry_estale - determine whether the caller should retry an operation
+ * @error: the error that would currently be returned
+ * @flags: flags being used for next lookup attempt
+ *
+ * Check to see if the error code was -ESTALE, and then determine whether
+ * to retry the call based on whether "flags" already has LOOKUP_REVAL set.
+ *
+ * Returns true if the caller should try the operation again.
+ */
+static inline bool
+retry_estale(const long error, const unsigned int flags)
+{
+ return error == -ESTALE && !(flags & LOOKUP_REVAL);
+}
+
+#endif /* _LINUX_NAMEI_H */