Unified UUID/GUID definition

There are many different UUID/GUID definitions in kernel, such as that
in EFI, many file systems, some drivers, etc. Every kernel components
need UUID/GUID has its own definition. This patch provides a unified
definition for UUID/GUID.

UUID is defined via typedef. This makes that UUID appears more like a
preliminary type, and makes the data type explicit (comparing with
implicit "u8 uuid[16]").

The binary representation of UUID/GUID can be little-endian (used by
EFI, etc) or big-endian (defined by RFC4122), so both is defined.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/lib/uuid.c b/lib/uuid.c
new file mode 100644
index 000000000000..8fadd7cef46c
--- /dev/null
+++ b/lib/uuid.c
@@ -0,0 +1,53 @@
+/*
+ * Unified UUID/GUID definition
+ *
+ * Copyright (C) 2009, Intel Corp.
+ *      Huang Ying <ying.huang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/uuid.h>
+#include <linux/random.h>
+
+static void __uuid_gen_common(__u8 b[16])
+{
+        int i;
+        u32 r;
+
+        for (i = 0; i < 4; i++) {
+                r = random32();
+                memcpy(b + i * 4, &r, 4);
+        }
+        /* reversion 0b10 */
+        b[8] = (b[8] & 0x3F) | 0x80;
+}
+
+void uuid_le_gen(uuid_le *lu)
+{
+        __uuid_gen_common(lu->b);
+        /* version 4 : random generation */
+        lu->b[7] = (lu->b[7] & 0x0F) | 0x40;
+}
+EXPORT_SYMBOL_GPL(uuid_le_gen);
+
+void uuid_be_gen(uuid_be *bu)
+{
+        __uuid_gen_common(bu->b);
+        /* version 4 : random generation */
+        bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
+}
+EXPORT_SYMBOL_GPL(uuid_be_gen);