1 files changed, 69 insertions, 0 deletions

diff --git a/include/linux/dcookies.h b/include/linux/dcookies.h
new file mode 100644
index 000000000000..c28050136164
--- /dev/null
+++ b/include/linux/dcookies.h
@@ -0,0 +1,69 @@
+/*
+ * dcookies.h
+ *
+ * Persistent cookie-path mappings
+ *
+ * Copyright 2002 John Levon <levon@movementarian.org>
+ */
+
+#ifndef DCOOKIES_H
+#define DCOOKIES_H
+ 
+#include <linux/config.h>
+
+#ifdef CONFIG_PROFILING
+ 
+#include <linux/types.h>
+ 
+struct dcookie_user;
+ 
+/**
+ * dcookie_register - register a user of dcookies
+ *
+ * Register as a dcookie user. Returns %NULL on failure.
+ */
+struct dcookie_user * dcookie_register(void);
+
+/**
+ * dcookie_unregister - unregister a user of dcookies
+ *
+ * Unregister as a dcookie user. This may invalidate
+ * any dcookie values returned from get_dcookie().
+ */
+void dcookie_unregister(struct dcookie_user * user);
+  
+/**
+ * get_dcookie - acquire a dcookie
+ *
+ * Convert the given dentry/vfsmount pair into
+ * a cookie value.
+ *
+ * Returns -EINVAL if no living task has registered as a
+ * dcookie user.
+ *
+ * Returns 0 on success, with *cookie filled in
+ */
+int get_dcookie(struct dentry * dentry, struct vfsmount * vfsmnt,
+        unsigned long * cookie);
+
+#else
+
+struct dcookie_user * dcookie_register(void)
+{
+        return NULL;
+}
+
+void dcookie_unregister(struct dcookie_user * user)
+{
+        return;
+}
+ 
+static inline int get_dcookie(struct dentry * dentry,
+        struct vfsmount * vfsmnt, unsigned long * cookie)
+{
+        return -ENOSYS;
+} 
+ 
+#endif /* CONFIG_PROFILING */
+ 
+#endif /* DCOOKIES_H */