Merge tag 'block-6.4-2023-06-09' of git://git.kernel.dk/linux

Pull block fixes from Jens Axboe:

 - Fix an issue with the hardware queue nr_active, causing it to become
   imbalanced (Tian)

 - Fix an issue with null_blk not releasing pages if configured as
   memory backed (Nitesh)

 - Fix a locking issue in dasd (Jan)

* tag 'block-6.4-2023-06-09' of git://git.kernel.dk/linux:
  s390/dasd: Use correct lock while counting channel queue length
  null_blk: Fix: memory release when memory_backed=1
  blk-mq: fix blk_mq_hw_ctx active request accounting

Author: torvalds

block/blk-mq.c

@@ -683,6 +683,10 @@ static void __blk_mq_free_request(struct request *rq)
 	blk_crypto_free_request(rq);
 	blk_pm_mark_last_busy(rq);
 	rq->mq_hctx = NULL;
+
+	if (rq->rq_flags & RQF_MQ_INFLIGHT)
+		__blk_mq_dec_active_requests(hctx);
+
 	if (rq->tag != BLK_MQ_NO_TAG)
 		blk_mq_put_tag(hctx->tags, ctx, rq->tag);
 	if (sched_tag != BLK_MQ_NO_TAG)
@@ -694,15 +698,11 @@ static void __blk_mq_free_request(struct request *rq)
 void blk_mq_free_request(struct request *rq)
 {
 	struct request_queue *q = rq->q;
-	struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
 
 	if ((rq->rq_flags & RQF_ELVPRIV) &&
 	    q->elevator->type->ops.finish_request)
 		q->elevator->type->ops.finish_request(rq);
 
-	if (rq->rq_flags & RQF_MQ_INFLIGHT)
-		__blk_mq_dec_active_requests(hctx);
-
 	if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq)))
 		laptop_io_completion(q->disk->bdi);
 

drivers/block/null_blk/main.c

@@ -2244,6 +2244,7 @@ static void null_destroy_dev(struct nullb *nullb)
 	struct nullb_device *dev = nullb->dev;
 
 	null_del_dev(nullb);
+	null_free_device_storage(dev, false);
 	null_free_dev(dev);
 }
 

drivers/s390/block/dasd_ioctl.c

@@ -552,10 +552,10 @@ static int __dasd_ioctl_information(struct dasd_block *block,
 
 	memcpy(dasd_info->type, base->discipline->name, 4);
 
-	spin_lock_irqsave(&block->queue_lock, flags);
+	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 	list_for_each(l, &base->ccw_queue)
 		dasd_info->chanq_len++;
-	spin_unlock_irqrestore(&block->queue_lock, flags);
+	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 	return 0;
 }