lib/uuid.c: move generate_random_uuid() to uuid.c

Let's gather the UUID related functions under one hood.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/uuid.c b/lib/uuid.c
index 398821e..6c81c0b 100644
--- a/lib/uuid.c
+++ b/lib/uuid.c
@@ -23,6 +23,26 @@
 #include <linux/uuid.h>
 #include <linux/random.h>
 
+/***************************************************************
+ * Random UUID interface
+ *
+ * Used here for a Boot ID, but can be useful for other kernel
+ * drivers.
+ ***************************************************************/
+
+/*
+ * Generate random UUID
+ */
+void generate_random_uuid(unsigned char uuid[16])
+{
+	get_random_bytes(uuid, 16);
+	/* Set UUID version to 4 --- truly random generation */
+	uuid[6] = (uuid[6] & 0x0F) | 0x40;
+	/* Set the UUID variant to DCE */
+	uuid[8] = (uuid[8] & 0x3F) | 0x80;
+}
+EXPORT_SYMBOL(generate_random_uuid);
+
 static void __uuid_gen_common(__u8 b[16])
 {
 	prandom_bytes(b, 16);