tree 9c33dd91350ea163b160d9f5cb40d913c5caf268
parent f615b48cc7df7cac3865ec76ac1a5bb04d3e07f4
author Tejun Heo <tj@kernel.org> 1219661245 +0900
committer Jens Axboe <jens.axboe@oracle.com> 1223535366 +0200

block: implement CONFIG_DEBUG_BLOCK_EXT_DEVT

Extended devt introduces non-contiguos device numbers.  This patch
implements a debug option which forces most devt allocations to be
from the extended area and spreads them out.  This is enabled by
default if DEBUG_KERNEL is set and achieves...

1. Detects code paths in kernel or userland which expect predetermined
   consecutive device numbers.

2. When something goes wrong, avoid corruption as adding to the minor
   of earlier partition won't lead to the wrong but valid device.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>