Well, it should just be a little blk_poll loop, right?
Not so much about the poll loop, but the fact that we will need
to check if we need to poll for this special case every time in
.queue_rq and its somewhat annoying...
I don't think we need to add any special check in queue_rq. Any
polled command should be marked as HIPRI from the submitting code,
and that includes the queue creation.
Hmm, good idea, perhaps adding something like to following:
--
/**
* blk_execute_rq_polled - execute a request and poll for its completion
* @q: queue to insert the request in
* @bd_disk: matching gendisk
* @rq: request to insert
* @at_head: insert request at head or tail of queue
*
* Description:
* Insert a fully prepared request at the back of the I/O scheduler
* queue for execution and poll for completion.
*/
void blk_execute_rq_polled(struct request_queue *q, struct gendisk *bd_disk,
struct request *rq, int at_head)
{
DECLARE_COMPLETION_ONSTACK(wait);
unsigned long hang_check;
rq->cmd_flags |= REQ_HIPRI;
rq->end_io_data = &wait;
blk_execute_rq_nowait(q, bd_disk, rq, at_head, blk_end_sync_rq);
while (!completion_done(&wait))
blk_poll(q, 0, true);
}
EXPORT_SYMBOL(blk_execute_rq_polled);
--
and __nvme_submit_sync_cmd() can receive a poll argument as well to call
blk_execute_req_polled()?
