From: Stephen Warren swarren@nvidia.com
The MSDOS/MBR partition table includes a 32-bit unique ID, often referred to as the NT disk signature. When combined with a partition number within the table, this can form a unique ID similar in concept to EFI/GPT's partition UUID.
This patch generates UUIDs in the format 0002dd75-01, which matches the format expected by the Linux kernel.
Signed-off-by: Stephen Warren swarren@nvidia.com --- v4: Rebased. v3: No change. v2: New patch. --- disk/part_dos.c | 15 ++++++++++++--- disk/part_dos.h | 2 +- 2 files changed, 13 insertions(+), 4 deletions(-)
diff --git a/disk/part_dos.c b/disk/part_dos.c index 24ac00c..c9a3e2b 100644 --- a/disk/part_dos.c +++ b/disk/part_dos.c @@ -169,7 +169,8 @@ static void print_partition_extended (block_dev_desc_t *dev_desc, int ext_part_s */ static int get_partition_info_extended (block_dev_desc_t *dev_desc, int ext_part_sector, int relative, int part_num, - int which_part, disk_partition_t *info) + int which_part, disk_partition_t *info, + unsigned int disksig) { ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz); dos_partition_t *pt; @@ -188,6 +189,11 @@ static int get_partition_info_extended (block_dev_desc_t *dev_desc, int ext_part return -1; }
+#ifdef CONFIG_PARTITION_UUIDS + if (!ext_part_sector) + disksig = le32_to_int(&buffer[DOS_PART_DISKSIG_OFFSET]); +#endif + /* Print all primary/logical partitions */ pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET); for (i = 0; i < 4; i++, pt++) { @@ -229,6 +235,9 @@ static int get_partition_info_extended (block_dev_desc_t *dev_desc, int ext_part /* sprintf(info->type, "%d, pt->sys_ind); */ sprintf ((char *)info->type, "U-Boot"); info->bootable = is_bootable(pt); +#ifdef CONFIG_PARTITION_UUIDS + sprintf(info->uuid, "%08x-%02x", disksig, part_num); +#endif return 0; }
@@ -247,7 +256,7 @@ static int get_partition_info_extended (block_dev_desc_t *dev_desc, int ext_part
return get_partition_info_extended (dev_desc, lba_start, ext_part_sector == 0 ? lba_start : relative, - part_num, which_part, info); + part_num, which_part, info, disksig); } } return -1; @@ -261,7 +270,7 @@ void print_part_dos (block_dev_desc_t *dev_desc)
int get_partition_info_dos (block_dev_desc_t *dev_desc, int part, disk_partition_t * info) { - return get_partition_info_extended (dev_desc, 0, 0, 1, part, info); + return get_partition_info_extended(dev_desc, 0, 0, 1, part, info, 0); }
diff --git a/disk/part_dos.h b/disk/part_dos.h index de75542..7b77c1d 100644 --- a/disk/part_dos.h +++ b/disk/part_dos.h @@ -24,7 +24,7 @@ #ifndef _DISK_PART_DOS_H #define _DISK_PART_DOS_H
- +#define DOS_PART_DISKSIG_OFFSET 0x1b8 #define DOS_PART_TBL_OFFSET 0x1be #define DOS_PART_MAGIC_OFFSET 0x1fe #define DOS_PBR_FSTYPE_OFFSET 0x36