[PATCH v11] NVMe: Convert to blk-mq

[Matias Bjorling]

On 08/15/2014 01:09 AM, Keith Busch wrote:
>
> The allocation and freeing of blk-mq parts seems a bit asymmetrical
> to me. The 'tags' belong to the tagset, but any request_queue using
> that tagset may free the tags. I looked to separate the tag allocation
> concerns, but that's more time than I have, so this is my quick-fix
> driver patch, forcing tag access through the hw_ctx.
>

I moved nvmeq->hctx->tags into nvmeq->tags in the last version. I missed 
the free's in blk_mq_map_swqueue. Good catch.

The previous method might have another problem. If there's two 
namespaces, sharing tag set. The hctx_init fn could be called with 
different hctx for an nvmeq, leading to false tag sharing between nvme 
queues.