tree 3e13c8e1028e3722be926487acae5473c1eda2be
parent 484b4061e6683e0e6a09c7455f80781128dc8a6b
author Jens Axboe <axboe@fb.com> 1400776851 -0600
committer Jens Axboe <axboe@fb.com> 1400776987 -0600

blk-mq: split make request handler for multi and single queue

We want slightly different behavior from them:

- On single queue devices, we currently use the per-process plug
  for deferred IO and for merging.

- On multi queue devices, we don't use the per-process plug, but
  we want to go straight to hardware for SYNC IO.

Split blk_mq_make_request() into a blk_sq_make_request() for single
queue devices, and retain blk_mq_make_request() for multi queue
devices. Then we don't need multiple checks for q->nr_hw_queues
in the request mapping.

Signed-off-by: Jens Axboe <axboe@fb.com>