[dm-devel] [PATCH 2/7 v2] blk-mq: add blk_mq_init_allocated_queue and export blk_mq_register_disk

[Hannes Reinecke]

On 03/12/2015 10:29 AM, Mike Snitzer wrote:
> Add a variant of blk_mq_init_queue that allows a previously allocated
> queue to be initialized.  blk_mq_init_allocated_queue models
> blk_init_allocated_queue -- which was also created for DM's use.
> 
> DM's approach to device creation requires a placeholder request_queue be
> allocated for use with alloc_dev() but the decision about what type of
> request_queue will be ultimately created is deferred until all component
> devices referenced in the DM table are processed to determine the table
> type (request-based, blk-mq request-based, or bio-based).
> 
> Also, because of DM's late finalization of the request_queue type
> the call to blk_mq_register_disk() doesn't happen during alloc_dev().
> Must export blk_mq_register_disk() so that DM can backfill the 'mq' dir
> once the blk-mq queue is fully allocated.
> 
> Signed-off-by: Mike Snitzer <snitzer at redhat.com>
> Reviewed-by: Ming Lei <ming.lei at canonical.com>

Reviewed-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
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