[Drbd-dev] [RFC PATCH 01/17] block: make generic_make_request handle arbitrarily sized bios

[Christoph Hellwig]

On Tue, Dec 23, 2014 at 12:41:40PM +0100, Dongsu Park wrote:
> You mean, checking rq->cmd_type == REQ_TYPE_BLOCK_PC, right?
> 
> I'm wondering about how to check that in blk_queue_split().
> At the moment when blk_queue_split() is called, it's even before a request
> is mapped e.g. in blk_sq_make_request().
> Unlike scsi drivers where it's easy to get cmd->rq, blk_queue_split()
> doesn't seem to be able to get a request by blk_get_request().
> 
> Or am I missing something?

You're probably missing what I didn't notice either: BLOCK_PC requests
are never sent through ->make_request.  Consider my comment withdrawn
and sorry for the confusion.