Merge tag 'block-5.5-20191221' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Let's try this one again, this time without the compat_ioctl changes.
  We've got those fixed up, but that can go out next week.

  This contains:

   - block queue flush lockdep annotation (Bart)

   - Type fix for bsg_queue_rq() (Bart)

   - Three dasd fixes (Stefan, Jan)

   - nbd deadlock fix (Mike)

   - Error handling bio user map fix (Yang)

   - iocost fix (Tejun)

   - sbitmap waitqueue addition fix that affects the kyber IO scheduler
     (David)"

* tag 'block-5.5-20191221' of git://git.kernel.dk/linux-block:
  sbitmap: only queue kyber's wait callback if not already active
  block: fix memleak when __blk_rq_map_user_iov() is failed
  s390/dasd: fix typo in copyright statement
  s390/dasd: fix memleak in path handling error case
  s390/dasd/cio: Interpret ccw_device_get_mdc return value correctly
  block: Fix a lockdep complaint triggered by request queue flushing
  block: Fix the type of 'sts' in bsg_queue_rq()
  block: end bio with BLK_STS_AGAIN in case of non-mq devs and REQ_NOWAIT
  nbd: fix shutdown and recv work deadlock v2
  iocost: over-budget forced IOs should schedule async delay

6 files changed, 23 insertions, 11 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index e0a094fddee5..089e890ab208 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -885,11 +885,14 @@ generic_make_request_checks(struct bio *bio)
 	}
 
 	/*
-	 * For a REQ_NOWAIT based request, return -EOPNOTSUPP
-	 * if queue is not a request based queue.
+	 * Non-mq queues do not honor REQ_NOWAIT, so complete a bio
+	 * with BLK_STS_AGAIN status in order to catch -EAGAIN and
+	 * to give a chance to the caller to repeat request gracefully.
 	 */
-	if ((bio->bi_opf & REQ_NOWAIT) && !queue_is_mq(q))
-		goto not_supported;
+	if ((bio->bi_opf & REQ_NOWAIT) && !queue_is_mq(q)) {
+		status = BLK_STS_AGAIN;
+		goto end_io;
+	}
 
 	if (should_fail_bio(bio))
 		goto end_io;
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 1777346baf06..3f977c517960 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -69,6 +69,7 @@
 #include <linux/blkdev.h>
 #include <linux/gfp.h>
 #include <linux/blk-mq.h>
+#include <linux/lockdep.h>
 
 #include "blk.h"
 #include "blk-mq.h"
@@ -505,6 +506,9 @@ struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
 	INIT_LIST_HEAD(&fq->flush_queue[1]);
 	INIT_LIST_HEAD(&fq->flush_data_in_flight);
 
+	lockdep_register_key(&fq->key);
+	lockdep_set_class(&fq->mq_flush_lock, &fq->key);
+
 	return fq;
 
  fail_rq:
@@ -519,6 +523,7 @@ void blk_free_flush_queue(struct blk_flush_queue *fq)
 	if (!fq)
 		return;
 
+	lockdep_unregister_key(&fq->key);
 	kfree(fq->flush_rq);
 	kfree(fq);
 }
diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index e01267f99183..27ca68621137 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -1212,7 +1212,7 @@ static enum hrtimer_restart iocg_waitq_timer_fn(struct hrtimer *timer)
 	return HRTIMER_NORESTART;
 }
 
-static void iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now, u64 cost)
+static bool iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now, u64 cost)
 {
 	struct ioc *ioc = iocg->ioc;
 	struct blkcg_gq *blkg = iocg_to_blkg(iocg);
@@ -1229,11 +1229,11 @@ static void iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now, u64 cost)
 	/* clear or maintain depending on the overage */
 	if (time_before_eq64(vtime, now->vnow)) {
 		blkcg_clear_delay(blkg);
-		return;
+		return false;
 	}
 	if (!atomic_read(&blkg->use_delay) &&
 	    time_before_eq64(vtime, now->vnow + vmargin))
-		return;
+		return false;
 
 	/* use delay */
 	if (cost) {
@@ -1250,10 +1250,11 @@ static void iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now, u64 cost)
 	oexpires = ktime_to_ns(hrtimer_get_softexpires(&iocg->delay_timer));
 	if (hrtimer_is_queued(&iocg->delay_timer) &&
 	    abs(oexpires - expires) <= margin_ns / 4)
-		return;
+		return true;
 
 	hrtimer_start_range_ns(&iocg->delay_timer, ns_to_ktime(expires),
 			       margin_ns / 4, HRTIMER_MODE_ABS);
+	return true;
 }
 
 static enum hrtimer_restart iocg_delay_timer_fn(struct hrtimer *timer)
@@ -1739,7 +1740,9 @@ static void ioc_rqos_throttle(struct rq_qos *rqos, struct bio *bio)
 	 */
 	if (bio_issue_as_root_blkg(bio) || fatal_signal_pending(current)) {
 		atomic64_add(abs_cost, &iocg->abs_vdebt);
-		iocg_kick_delay(iocg, &now, cost);
+		if (iocg_kick_delay(iocg, &now, cost))
+			blkcg_schedule_throttle(rqos->q,
+					(bio->bi_opf & REQ_SWAP) == REQ_SWAP);
 		return;
 	}
 
diff --git a/block/blk-map.c b/block/blk-map.c
index 3a62e471d81b..b0790268ed9d 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -151,7 +151,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 	return 0;
 
 unmap_rq:
-	__blk_rq_unmap_user(bio);
+	blk_rq_unmap_user(bio);
 fail:
 	rq->bio = NULL;
 	return ret;
diff --git a/block/blk.h b/block/blk.h
index 6842f28c033e..0b8884353f6b 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -30,6 +30,7 @@ struct blk_flush_queue {
 	 * at the same time
 	 */
 	struct request		*orig_rq;
+	struct lock_class_key	key;
 	spinlock_t		mq_flush_lock;
 };
 
diff --git a/block/bsg-lib.c b/block/bsg-lib.c
index 347dda16c2f4..6cbb7926534c 100644
--- a/block/bsg-lib.c
+++ b/block/bsg-lib.c
@@ -266,7 +266,7 @@ static blk_status_t bsg_queue_rq(struct blk_mq_hw_ctx *hctx,
 	struct request *req = bd->rq;
 	struct bsg_set *bset =
 		container_of(q->tag_set, struct bsg_set, tag_set);
-	int sts = BLK_STS_IOERR;
+	blk_status_t sts = BLK_STS_IOERR;
 	int ret;
 
 	blk_mq_start_request(req);