diff options
| author | Stephen Warren <swarren@nvidia.com> | 2012-11-08 16:12:28 -0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2012-11-23 14:28:58 +0100 |
| commit | d33b98fc82b0908e91fb05ae081acaed7323f9d2 (patch) | |
| tree | fe5803ac8510ab46f0fcbcc1712343806699a5cb /init/do_mounts.c | |
| parent | 283f8fc03927b0ef42a2faa60a0df5ec8c612edb (diff) | |
| download | lwn-d33b98fc82b0908e91fb05ae081acaed7323f9d2.tar.gz lwn-d33b98fc82b0908e91fb05ae081acaed7323f9d2.zip | |
block: partition: msdos: provide UUIDs for partitions
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. Constructing and recording this value in struct
partition_meta_info allows MSDOS partitions to be referred to on the
kernel command-line using the following syntax:
root=PARTUUID=0002dd75-01
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Will Drewry <wad@chromium.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'init/do_mounts.c')
| -rw-r--r-- | init/do_mounts.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/init/do_mounts.c b/init/do_mounts.c index c950d7c93f98..1d1b6348f903 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -189,6 +189,10 @@ done: * used when disk name of partitioned disk ends on a digit. * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the * unique id of a partition if the partition table provides it. + * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS + * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero- + * filled hex representation of the 32-bit "NT disk signature", and PP + * is a zero-filled hex representation of the 1-based partition number. * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to * a partition with a known unique id. * |