block: kill legacy parts of timeout handling

The only user of legacy timing now is BSG, which is invoked
from the mq timeout handler. Kill the legacy code, and rename
the q->rq_timed_out_fn to q->bsg_job_timeout_fn.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-timeout.c b/block/blk-timeout.c
index f2cfd56..6428d45 100644
--- a/block/blk-timeout.c
+++ b/block/blk-timeout.c
@@ -78,70 +78,6 @@ void blk_delete_timer(struct request *req)
 	list_del_init(&req->timeout_list);
 }
 
-static void blk_rq_timed_out(struct request *req)
-{
-	struct request_queue *q = req->q;
-	enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER;
-
-	if (q->rq_timed_out_fn)
-		ret = q->rq_timed_out_fn(req);
-	switch (ret) {
-	case BLK_EH_RESET_TIMER:
-		blk_add_timer(req);
-		blk_clear_rq_complete(req);
-		break;
-	case BLK_EH_DONE:
-		/*
-		 * LLD handles this for now but in the future
-		 * we can send a request msg to abort the command
-		 * and we can move more of the generic scsi eh code to
-		 * the blk layer.
-		 */
-		break;
-	default:
-		printk(KERN_ERR "block: bad eh return: %d\n", ret);
-		break;
-	}
-}
-
-static void blk_rq_check_expired(struct request *rq, unsigned long *next_timeout,
-			  unsigned int *next_set)
-{
-	const unsigned long deadline = blk_rq_deadline(rq);
-
-	if (time_after_eq(jiffies, deadline)) {
-		list_del_init(&rq->timeout_list);
-
-		/*
-		 * Check if we raced with end io completion
-		 */
-		if (!blk_mark_rq_complete(rq))
-			blk_rq_timed_out(rq);
-	} else if (!*next_set || time_after(*next_timeout, deadline)) {
-		*next_timeout = deadline;
-		*next_set = 1;
-	}
-}
-
-void blk_timeout_work(struct work_struct *work)
-{
-	struct request_queue *q =
-		container_of(work, struct request_queue, timeout_work);
-	unsigned long flags, next = 0;
-	struct request *rq, *tmp;
-	int next_set = 0;
-
-	spin_lock_irqsave(q->queue_lock, flags);
-
-	list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list)
-		blk_rq_check_expired(rq, &next, &next_set);
-
-	if (next_set)
-		mod_timer(&q->timeout, round_jiffies_up(next));
-
-	spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
 /**
  * blk_abort_request -- Request request recovery for the specified command
  * @req:	pointer to the request of interest
@@ -153,20 +89,13 @@ void blk_timeout_work(struct work_struct *work)
  */
 void blk_abort_request(struct request *req)
 {
-	if (req->q->mq_ops) {
-		/*
-		 * All we need to ensure is that timeout scan takes place
-		 * immediately and that scan sees the new timeout value.
-		 * No need for fancy synchronizations.
-		 */
-		blk_rq_set_deadline(req, jiffies);
-		kblockd_schedule_work(&req->q->timeout_work);
-	} else {
-		if (blk_mark_rq_complete(req))
-			return;
-		blk_delete_timer(req);
-		blk_rq_timed_out(req);
-	}
+	/*
+	 * All we need to ensure is that timeout scan takes place
+	 * immediately and that scan sees the new timeout value.
+	 * No need for fancy synchronizations.
+	 */
+	blk_rq_set_deadline(req, jiffies);
+	kblockd_schedule_work(&req->q->timeout_work);
 }
 EXPORT_SYMBOL_GPL(blk_abort_request);
 
@@ -194,13 +123,6 @@ void blk_add_timer(struct request *req)
 	struct request_queue *q = req->q;
 	unsigned long expiry;
 
-	if (!q->mq_ops)
-		lockdep_assert_held(q->queue_lock);
-
-	/* blk-mq has its own handler, so we don't need ->rq_timed_out_fn */
-	if (!q->mq_ops && !q->rq_timed_out_fn)
-		return;
-
 	BUG_ON(!list_empty(&req->timeout_list));
 
 	/*
@@ -214,13 +136,6 @@ void blk_add_timer(struct request *req)
 	blk_rq_set_deadline(req, jiffies + req->timeout);
 
 	/*
-	 * Only the non-mq case needs to add the request to a protected list.
-	 * For the mq case we simply scan the tag map.
-	 */
-	if (!q->mq_ops)
-		list_add_tail(&req->timeout_list, &req->q->timeout_list);
-
-	/*
 	 * If the timer isn't already pending or this timeout is earlier
 	 * than an existing one, modify the timer. Round up to next nearest
 	 * second.