wic: generate PARTUUID for MDOS partitions

Added generation of partition UUIDs for MSDOS partitions.
UUID for MSDOS partitions is <disk identifier>-<partition number>,
where disk identifier is a random 4 bytes long number. It's usually
generated when MBR/partition table is initialized.

As UUID is used to point to the root partition in bootloader config
we need to generate it before the MBR is initialized.
After MBR is created we need to rewrite system identifier to match
it with what is used in bootloader config. This will be implemented
in the next commit.

Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/scripts/lib/wic/imager/direct.py b/scripts/lib/wic/imager/direct.py
index ffde232c2b0039af69e0eb2119ed881970ee25cb..123a07817beb3702956f20bd3ace602e16252ef1 100644 (file)
--- a/scripts/lib/wic/imager/direct.py
+++ b/scripts/lib/wic/imager/direct.py
@@ -26,6 +26,7 @@
 
 import os
 import shutil
+import uuid
 
 from wic import msger
 from wic.utils.oe.misc import get_bitbake_var
@@ -242,12 +243,23 @@ class DirectImageCreator(BaseImageCreator):
 
         self.__image = Image(self.native_sysroot)
 
-        for part in parts:
+        disk_ids = {}
+        for num, part in enumerate(parts, 1):
             # as a convenience, set source to the boot partition source
             # instead of forcing it to be set via bootloader --source
             if not self.ks.bootloader.source and part.mountpoint == "/boot":
                 self.ks.bootloader.source = part.source
 
+            # generate parition UUIDs
+            if not part.uuid and part.use_uuid:
+                if self.ptable_format == 'gpt':
+                    part.uuid = str(uuid.uuid4())
+                else: # msdos partition table
+                    if part.disk not in disk_ids:
+                        disk_ids[part.disk] = int.from_bytes(os.urandom(4), 'little')
+                    disk_id = disk_ids[part.disk]
+                    part.uuid = '%0x-%02d' % (disk_id, self.__get_part_num(num, parts))
+
         fstab_path = self._write_fstab(self.rootfs_dir.get("ROOTFS_DIR"))
 
         shutil.rmtree(self.workdir)

diff --git a/scripts/lib/wic/partition.py b/scripts/lib/wic/partition.py
index 30cd320a309b35f74d3b0904285e2f430e14ea5c..90f65a1e3976a5460cd1b265b238168cce22781f 100644 (file)
--- a/scripts/lib/wic/partition.py
+++ b/scripts/lib/wic/partition.py
@@ -26,7 +26,6 @@
 
 import os
 import tempfile
-import uuid
 
 from wic.utils.oe.misc import msger, parse_sourceparams
 from wic.utils.oe.misc import exec_cmd, exec_native_cmd
@@ -60,8 +59,6 @@ class Partition():
         self.system_id = args.system_id
         self.use_uuid = args.use_uuid
         self.uuid = args.uuid
-        if args.use_uuid and not self.uuid:
-            self.uuid = str(uuid.uuid4())
 
         self.lineno = lineno
         self.source_file = ""