Merge tag 'for-6.3/block-2023-02-16' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe updates via Christoph:
      - Small improvements to the logging functionality (Amit Engel)
      - Authentication cleanups (Hannes Reinecke)
      - Cleanup and optimize the DMA mapping cod in the PCIe driver
        (Keith Busch)
      - Work around the command effects for Format NVM (Keith Busch)
      - Misc cleanups (Keith Busch, Christoph Hellwig)
      - Fix and cleanup freeing single sgl (Keith Busch)

 - MD updates via Song:
      - Fix a rare crash during the takeover process
      - Don't update recovery_cp when curr_resync is ACTIVE
      - Free writes_pending in md_stop
      - Change active_io to percpu

 - Updates to drbd, inching us closer to unifying the out-of-tree driver
   with the in-tree one (Andreas, Christoph, Lars, Robert)

 - BFQ update adding support for multi-actuator drives (Paolo, Federico,
   Davide)

 - Make brd compliant with REQ_NOWAIT (me)

 - Fix for IOPOLL and queue entering, fixing stalled IO waiting on
   timeouts (me)

 - Fix for REQ_NOWAIT with multiple bios (me)

 - Fix memory leak in blktrace cleanup (Greg)

 - Clean up sbitmap and fix a potential hang (Kemeng)

 - Clean up some bits in BFQ, and fix a bug in the request injection
   (Kemeng)

 - Clean up the request allocation and issue code, and fix some bugs
   related to that (Kemeng)

 - ublk updates and fixes:
      - Add support for unprivileged ublk (Ming)
      - Improve device deletion handling (Ming)
      - Misc (Liu, Ziyang)

 - s390 dasd fixes (Alexander, Qiheng)

 - Improve utility of request caching and fixes (Anuj, Xiao)

 - zoned cleanups (Pankaj)

 - More constification for kobjs (Thomas)

 - blk-iocost cleanups (Yu)

 - Remove bio splitting from drivers that don't need it (Christoph)

 - Switch blk-cgroups to use struct gendisk. Some of this is now
   incomplete as select late reverts were done. (Christoph)

 - Add bvec initialization helpers, and convert callers to use that
   rather than open-coding it (Christoph)

 - Misc fixes and cleanups (Jinke, Keith, Arnd, Bart, Li, Martin,
   Matthew, Ulf, Zhong)

* tag 'for-6.3/block-2023-02-16' of git://git.kernel.dk/linux: (169 commits)
  brd: use radix_tree_maybe_preload instead of radix_tree_preload
  block: use proper return value from bio_failfast()
  block: bio-integrity: Copy flags when bio_integrity_payload is cloned
  block: Fix io statistics for cgroup in throttle path
  brd: mark as nowait compatible
  brd: check for REQ_NOWAIT and set correct page allocation mask
  brd: return 0/-error from brd_insert_page()
  block: sync mixed merged request's failfast with 1st bio's
  Revert "blk-cgroup: pin the gendisk in struct blkcg_gq"
  Revert "blk-cgroup: pass a gendisk to blkg_lookup"
  Revert "blk-cgroup: delay blk-cgroup initialization until add_disk"
  Revert "blk-cgroup: delay calling blkcg_exit_disk until disk_release"
  Revert "blk-cgroup: move the cgroup information to struct gendisk"
  nvme-pci: remove iod use_sgls
  nvme-pci: fix freeing single sgl
  block: ublk: check IO buffer based on flag need_get_data
  s390/dasd: Fix potential memleak in dasd_eckd_init()
  s390/dasd: sort out physical vs virtual pointers usage
  block: Remove the ALLOC_CACHE_SLACK constant
  block: make kobj_type structures constant
  ...

34 files changed, 1128 insertions, 780 deletions

diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched
index 615516146086..27f11320b8d1 100644
--- a/block/Kconfig.iosched
+++ b/block/Kconfig.iosched
@@ -30,6 +30,7 @@ config IOSCHED_BFQ
 config BFQ_GROUP_IOSCHED
        bool "BFQ hierarchical scheduling support"
        depends on IOSCHED_BFQ && BLK_CGROUP
+       default y
        select BLK_CGROUP_RWSTAT
 	help
 
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index 0fbde0fc0628..89ffb3aa992c 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -513,12 +513,12 @@ static void bfq_cpd_free(struct blkcg_policy_data *cpd)
 	kfree(cpd_to_bfqgd(cpd));
 }
 
-static struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, struct request_queue *q,
-					     struct blkcg *blkcg)
+static struct blkg_policy_data *bfq_pd_alloc(struct gendisk *disk,
+		struct blkcg *blkcg, gfp_t gfp)
 {
 	struct bfq_group *bfqg;
 
-	bfqg = kzalloc_node(sizeof(*bfqg), gfp, q->node);
+	bfqg = kzalloc_node(sizeof(*bfqg), gfp, disk->node_id);
 	if (!bfqg)
 		return NULL;
 
@@ -551,7 +551,6 @@ static void bfq_pd_init(struct blkg_policy_data *pd)
 	bfqg->bfqd = bfqd;
 	bfqg->active_entities = 0;
 	bfqg->num_queues_with_pending_reqs = 0;
-	bfqg->online = true;
 	bfqg->rq_pos_tree = RB_ROOT;
 }
 
@@ -614,7 +613,7 @@ struct bfq_group *bfq_bio_bfqg(struct bfq_data *bfqd, struct bio *bio)
 			continue;
 		}
 		bfqg = blkg_to_bfqg(blkg);
-		if (bfqg->online) {
+		if (bfqg->pd.online) {
 			bio_associate_blkg_from_css(bio, &blkg->blkcg->css);
 			return bfqg;
 		}
@@ -706,12 +705,52 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 		bfq_activate_bfqq(bfqd, bfqq);
 	}
 
-	if (!bfqd->in_service_queue && !bfqd->rq_in_driver)
+	if (!bfqd->in_service_queue && !bfqd->tot_rq_in_driver)
 		bfq_schedule_dispatch(bfqd);
 	/* release extra ref taken above, bfqq may happen to be freed now */
 	bfq_put_queue(bfqq);
 }
 
+static void bfq_sync_bfqq_move(struct bfq_data *bfqd,
+			       struct bfq_queue *sync_bfqq,
+			       struct bfq_io_cq *bic,
+			       struct bfq_group *bfqg,
+			       unsigned int act_idx)
+{
+	struct bfq_queue *bfqq;
+
+	if (!sync_bfqq->new_bfqq && !bfq_bfqq_coop(sync_bfqq)) {
+		/* We are the only user of this bfqq, just move it */
+		if (sync_bfqq->entity.sched_data != &bfqg->sched_data)
+			bfq_bfqq_move(bfqd, sync_bfqq, bfqg);
+		return;
+	}
+
+	/*
+	 * The queue was merged to a different queue. Check
+	 * that the merge chain still belongs to the same
+	 * cgroup.
+	 */
+	for (bfqq = sync_bfqq; bfqq; bfqq = bfqq->new_bfqq)
+		if (bfqq->entity.sched_data != &bfqg->sched_data)
+			break;
+	if (bfqq) {
+		/*
+		 * Some queue changed cgroup so the merge is not valid
+		 * anymore. We cannot easily just cancel the merge (by
+		 * clearing new_bfqq) as there may be other processes
+		 * using this queue and holding refs to all queues
+		 * below sync_bfqq->new_bfqq. Similarly if the merge
+		 * already happened, we need to detach from bfqq now
+		 * so that we cannot merge bio to a request from the
+		 * old cgroup.
+		 */
+		bfq_put_cooperator(sync_bfqq);
+		bic_set_bfqq(bic, NULL, true, act_idx);
+		bfq_release_process_ref(bfqd, sync_bfqq);
+	}
+}
+
 /**
  * __bfq_bic_change_cgroup - move @bic to @bfqg.
  * @bfqd: the queue descriptor.
@@ -726,53 +765,20 @@ static void __bfq_bic_change_cgroup(struct bfq_data *bfqd,
 				    struct bfq_io_cq *bic,
 				    struct bfq_group *bfqg)
 {
-	struct bfq_queue *async_bfqq = bic_to_bfqq(bic, false);
-	struct bfq_queue *sync_bfqq = bic_to_bfqq(bic, true);
-	struct bfq_entity *entity;
+	unsigned int act_idx;
 
-	if (async_bfqq) {
-		entity = &async_bfqq->entity;
+	for (act_idx = 0; act_idx < bfqd->num_actuators; act_idx++) {
+		struct bfq_queue *async_bfqq = bic_to_bfqq(bic, false, act_idx);
+		struct bfq_queue *sync_bfqq = bic_to_bfqq(bic, true, act_idx);
 
-		if (entity->sched_data != &bfqg->sched_data) {
-			bic_set_bfqq(bic, NULL, false);
+		if (async_bfqq &&
+		    async_bfqq->entity.sched_data != &bfqg->sched_data) {
+			bic_set_bfqq(bic, NULL, false, act_idx);
 			bfq_release_process_ref(bfqd, async_bfqq);
 		}
-	}
 
-	if (sync_bfqq) {
-		if (!sync_bfqq->new_bfqq && !bfq_bfqq_coop(sync_bfqq)) {
-			/* We are the only user of this bfqq, just move it */
-			if (sync_bfqq->entity.sched_data != &bfqg->sched_data)
-				bfq_bfqq_move(bfqd, sync_bfqq, bfqg);
-		} else {
-			struct bfq_queue *bfqq;
-
-			/*
-			 * The queue was merged to a different queue. Check
-			 * that the merge chain still belongs to the same
-			 * cgroup.
-			 */
-			for (bfqq = sync_bfqq; bfqq; bfqq = bfqq->new_bfqq)
-				if (bfqq->entity.sched_data !=
-				    &bfqg->sched_data)
-					break;
-			if (bfqq) {
-				/*
-				 * Some queue changed cgroup so the merge is
-				 * not valid anymore. We cannot easily just
-				 * cancel the merge (by clearing new_bfqq) as
-				 * there may be other processes using this
-				 * queue and holding refs to all queues below
-				 * sync_bfqq->new_bfqq. Similarly if the merge
-				 * already happened, we need to detach from
-				 * bfqq now so that we cannot merge bio to a
-				 * request from the old cgroup.
-				 */
-				bfq_put_cooperator(sync_bfqq);
-				bic_set_bfqq(bic, NULL, true);
-				bfq_release_process_ref(bfqd, sync_bfqq);
-			}
-		}
+		if (sync_bfqq)
+			bfq_sync_bfqq_move(bfqd, sync_bfqq, bic, bfqg, act_idx);
 	}
 }
 
@@ -978,7 +984,6 @@ static void bfq_pd_offline(struct blkg_policy_data *pd)
 
 put_async_queues:
 	bfq_put_async_queues(bfqd, bfqg);
-	bfqg->online = false;
 
 	spin_unlock_irqrestore(&bfqd->lock, flags);
 	/*
@@ -1284,7 +1289,7 @@ struct bfq_group *bfq_create_group_hierarchy(struct bfq_data *bfqd, int node)
 {
 	int ret;
 
-	ret = blkcg_activate_policy(bfqd->queue, &blkcg_policy_bfq);
+	ret = blkcg_activate_policy(bfqd->queue->disk, &blkcg_policy_bfq);
 	if (ret)
 		return NULL;
 
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 380e9bda2e57..8a8d4441519c 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -377,20 +377,23 @@ static const unsigned long bfq_late_stable_merging = 600;
 #define RQ_BIC(rq)		((struct bfq_io_cq *)((rq)->elv.priv[0]))
 #define RQ_BFQQ(rq)		((rq)->elv.priv[1])
 
-struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync)
+struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync,
+			      unsigned int actuator_idx)
 {
-	return bic->bfqq[is_sync];
+	if (is_sync)
+		return bic->bfqq[1][actuator_idx];
+
+	return bic->bfqq[0][actuator_idx];
 }
 
 static void bfq_put_stable_ref(struct bfq_queue *bfqq);
 
-void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync)
+void bic_set_bfqq(struct bfq_io_cq *bic,
+		  struct bfq_queue *bfqq,
+		  bool is_sync,
+		  unsigned int actuator_idx)
 {
-	struct bfq_queue *old_bfqq = bic->bfqq[is_sync];
-
-	/* Clear bic pointer if bfqq is detached from this bic */
-	if (old_bfqq && old_bfqq->bic == bic)
-		old_bfqq->bic = NULL;
+	struct bfq_queue *old_bfqq = bic->bfqq[is_sync][actuator_idx];
 
 	/*
 	 * If bfqq != NULL, then a non-stable queue merge between
@@ -405,9 +408,18 @@ void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync)
 	 * we cancel the stable merge if
 	 * bic->stable_merge_bfqq == bfqq.
 	 */
-	bic->bfqq[is_sync] = bfqq;
+	struct bfq_iocq_bfqq_data *bfqq_data = &bic->bfqq_data[actuator_idx];
+
+	/* Clear bic pointer if bfqq is detached from this bic */
+	if (old_bfqq && old_bfqq->bic == bic)
+		old_bfqq->bic = NULL;
 
-	if (bfqq && bic->stable_merge_bfqq == bfqq) {
+	if (is_sync)
+		bic->bfqq[1][actuator_idx] = bfqq;
+	else
+		bic->bfqq[0][actuator_idx] = bfqq;
+
+	if (bfqq && bfqq_data->stable_merge_bfqq == bfqq) {
 		/*
 		 * Actually, these same instructions are executed also
 		 * in bfq_setup_cooperator, in case of abort or actual
@@ -416,9 +428,9 @@ void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync)
 		 * did so, we would nest even more complexity in this
 		 * function.
 		 */
-		bfq_put_stable_ref(bic->stable_merge_bfqq);
+		bfq_put_stable_ref(bfqq_data->stable_merge_bfqq);
 
-		bic->stable_merge_bfqq = NULL;
+		bfqq_data->stable_merge_bfqq = NULL;
 	}
 }
 
@@ -678,9 +690,9 @@ static void bfq_limit_depth(blk_opf_t opf, struct blk_mq_alloc_data *data)
 {
 	struct bfq_data *bfqd = data->q->elevator->elevator_data;
 	struct bfq_io_cq *bic = bfq_bic_lookup(data->q);
-	struct bfq_queue *bfqq = bic ? bic_to_bfqq(bic, op_is_sync(opf)) : NULL;
 	int depth;
 	unsigned limit = data->q->nr_requests;
+	unsigned int act_idx;
 
 	/* Sync reads have full depth available */
 	if (op_is_sync(opf) && !op_is_write(opf)) {
@@ -690,14 +702,21 @@ static void bfq_limit_depth(blk_opf_t opf, struct blk_mq_alloc_data *data)
 		limit = (limit * depth) >> bfqd->full_depth_shift;
 	}
 
-	/*
-	 * Does queue (or any parent entity) exceed number of requests that
-	 * should be available to it? Heavily limit depth so that it cannot
-	 * consume more available requests and thus starve other entities.
-	 */
-	if (bfqq && bfqq_request_over_limit(bfqq, limit))
-		depth = 1;
+	for (act_idx = 0; bic && act_idx < bfqd->num_actuators; act_idx++) {
+		struct bfq_queue *bfqq =
+			bic_to_bfqq(bic, op_is_sync(opf), act_idx);
 
+		/*
+		 * Does queue (or any parent entity) exceed number of
+		 * requests that should be available to it? Heavily
+		 * limit depth so that it cannot consume more
+		 * available requests and thus starve other entities.
+		 */
+		if (bfqq && bfqq_request_over_limit(bfqq, limit)) {
+			depth = 1;
+			break;
+		}
+	}
 	bfq_log(bfqd, "[%s] wr_busy %d sync %d depth %u",
 		__func__, bfqd->wr_busy_queues, op_is_sync(opf), depth);
 	if (depth)
@@ -1074,9 +1093,6 @@ static unsigned int bfq_wr_duration(struct bfq_data *bfqd)
 {
 	u64 dur;
 
-	if (bfqd->bfq_wr_max_time > 0)
-		return bfqd->bfq_wr_max_time;
-
 	dur = bfqd->rate_dur_prod;
 	do_div(dur, bfqd->peak_rate);
 
@@ -1118,36 +1134,39 @@ bfq_bfqq_resume_state(struct bfq_queue *bfqq, struct bfq_data *bfqd,
 {
 	unsigned int old_wr_coeff = 1;
 	bool busy = bfq_already_existing && bfq_bfqq_busy(bfqq);
+	unsigned int a_idx = bfqq->actuator_idx;
+	struct bfq_iocq_bfqq_data *bfqq_data = &bic->bfqq_data[a_idx];
 
-	if (bic->saved_has_short_ttime)
+	if (bfqq_data->saved_has_short_ttime)
 		bfq_mark_bfqq_has_short_ttime(bfqq);
 	else
 		bfq_clear_bfqq_has_short_ttime(bfqq);
 
-	if (bic->saved_IO_bound)
+	if (bfqq_data->saved_IO_bound)
 		bfq_mark_bfqq_IO_bound(bfqq);
 	else
 		bfq_clear_bfqq_IO_bound(bfqq);
 
-	bfqq->last_serv_time_ns = bic->saved_last_serv_time_ns;
-	bfqq->inject_limit = bic->saved_inject_limit;
-	bfqq->decrease_time_jif = bic->saved_decrease_time_jif;
+	bfqq->last_serv_time_ns = bfqq_data->saved_last_serv_time_ns;
+	bfqq->inject_limit = bfqq_data->saved_inject_limit;
+	bfqq->decrease_time_jif = bfqq_data->saved_decrease_time_jif;
 
-	bfqq->entity.new_weight = bic->saved_weight;
-	bfqq->ttime = bic->saved_ttime;
-	bfqq->io_start_time = bic->saved_io_start_time;
-	bfqq->tot_idle_time = bic->saved_tot_idle_time;
+	bfqq->entity.new_weight = bfqq_data->saved_weight;
+	bfqq->ttime = bfqq_data->saved_ttime;
+	bfqq->io_start_time = bfqq_data->saved_io_start_time;
+	bfqq->tot_idle_time = bfqq_data->saved_tot_idle_time;
 	/*
 	 * Restore weight coefficient only if low_latency is on
 	 */
 	if (bfqd->low_latency) {
 		old_wr_coeff = bfqq->wr_coeff;
-		bfqq->wr_coeff = bic->saved_wr_coeff;
+		bfqq->wr_coeff = bfqq_data->saved_wr_coeff;
 	}
-	bfqq->service_from_wr = bic->saved_service_from_wr;
-	bfqq->wr_start_at_switch_to_srt = bic->saved_wr_start_at_switch_to_srt;
-	bfqq->last_wr_start_finish = bic->saved_last_wr_start_finish;
-	bfqq->wr_cur_max_time = bic->saved_wr_cur_max_time;
+	bfqq->service_from_wr = bfqq_data->saved_service_from_wr;
+	bfqq->wr_start_at_switch_to_srt =
+		bfqq_data->saved_wr_start_at_switch_to_srt;
+	bfqq->last_wr_start_finish = bfqq_data->saved_last_wr_start_finish;
+	bfqq->wr_cur_max_time = bfqq_data->saved_wr_cur_max_time;
 
 	if (bfqq->wr_coeff > 1 && (bfq_bfqq_in_large_burst(bfqq) ||
 	    time_is_before_jiffies(bfqq->last_wr_start_finish +
@@ -1766,6 +1785,33 @@ static bool bfq_bfqq_higher_class_or_weight(struct bfq_queue *bfqq,
 	return bfqq_weight > in_serv_weight;
 }
 
+/*
+ * Get the index of the actuator that will serve bio.
+ */
+static unsigned int bfq_actuator_index(struct bfq_data *bfqd, struct bio *bio)
+{
+	unsigned int i;
+	sector_t end;
+
+	/* no search needed if one or zero ranges present */
+	if (bfqd->num_actuators == 1)
+		return 0;
+
+	/* bio_end_sector(bio) gives the sector after the last one */
+	end = bio_end_sector(bio) - 1;
+
+	for (i = 0; i < bfqd->num_actuators; i++) {
+		if (end >= bfqd->sector[i] &&
+		    end < bfqd->sector[i] + bfqd->nr_sectors[i])
+			return i;
+	}
+
+	WARN_ONCE(true,
+		  "bfq_actuator_index: bio sector out of ranges: end=%llu\n",
+		  end);
+	return 0;
+}
+
 static bool bfq_better_to_idle(struct bfq_queue *bfqq);
 
 static void bfq_bfqq_handle_idle_busy_switch(struct bfq_data *bfqd,
@@ -1785,7 +1831,9 @@ static void bfq_bfqq_handle_idle_busy_switch(struct bfq_data *bfqd,
 		arrived_in_time =  ktime_get_ns() <=
 			bfqq->ttime.last_end_request +
 			bfqd->bfq_slice_idle * 3;
-
+	unsigned int act_idx = bfq_actuator_index(bfqd, rq->bio);
+	bool bfqq_non_merged_or_stably_merged =
+		bfqq->bic || RQ_BIC(rq)->bfqq_data[act_idx].stably_merged;
 
 	/*
 	 * bfqq deserves to be weight-raised if:
@@ -1819,9 +1867,8 @@ static void bfq_bfqq_handle_idle_busy_switch(struct bfq_data *bfqd,
 	 */
 	wr_or_deserves_wr = bfqd->low_latency &&
 		(bfqq->wr_coeff > 1 ||
-		 (bfq_bfqq_sync(bfqq) &&
-		  (bfqq->bic || RQ_BIC(rq)->stably_merged) &&
-		   (*interactive || soft_rt)));
+		 (bfq_bfqq_sync(bfqq) && bfqq_non_merged_or_stably_merged &&
+		  (*interactive || soft_rt)));
 
 	/*
 	 * Using the last flag, update budget and check whether bfqq
@@ -2098,7 +2145,7 @@ static void bfq_check_waker(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 	 * We reset waker detection logic also if too much time has passed
  	 * since the first detection. If wakeups are rare, pointless idling
 	 * doesn't hurt throughput that much. The condition below makes sure
-	 * we do not uselessly idle blocking waker in more than 1/64 cases. 
+	 * we do not uselessly idle blocking waker in more than 1/64 cases.
 	 */
 	if (bfqd->last_completed_rq_bfqq !=
 	    bfqq->tentative_waker_bfqq ||
@@ -2209,9 +2256,9 @@ static void bfq_add_request(struct request *rq)
 		 *   elapsed.
 		 */
 		if (bfqq == bfqd->in_service_queue &&
-		    (bfqd->rq_in_driver == 0 ||
+		    (bfqd->tot_rq_in_driver == 0 ||
 		     (bfqq->last_serv_time_ns > 0 &&
-		      bfqd->rqs_injected && bfqd->rq_in_driver > 0)) &&
+		      bfqd->rqs_injected && bfqd->tot_rq_in_driver > 0)) &&
 		    time_is_before_eq_jiffies(bfqq->decrease_time_jif +
 					      msecs_to_jiffies(10))) {
 			bfqd->last_empty_occupied_ns = ktime_get_ns();
@@ -2235,7 +2282,7 @@ static void bfq_add_request(struct request *rq)
 			 * will be set in case injection is performed
 			 * on bfqq before rq is completed).
 			 */
-			if (bfqd->rq_in_driver == 0)
+			if (bfqd->tot_rq_in_driver == 0)
 				bfqd->rqs_injected = false;
 		}
 	}
@@ -2418,7 +2465,8 @@ static bool bfq_bio_merge(struct request_queue *q, struct bio *bio,
 		 */
 		bfq_bic_update_cgroup(bic, bio);
 
-		bfqd->bio_bfqq = bic_to_bfqq(bic, op_is_sync(bio->bi_opf));
+		bfqd->bio_bfqq = bic_to_bfqq(bic, op_is_sync(bio->bi_opf),
+					     bfq_actuator_index(bfqd, bio));
 	} else {
 		bfqd->bio_bfqq = NULL;
 	}
@@ -2584,24 +2632,29 @@ static void bfq_bfqq_end_wr(struct bfq_queue *bfqq)
 void bfq_end_wr_async_queues(struct bfq_data *bfqd,
 			     struct bfq_group *bfqg)
 {
-	int i, j;
+	int i, j, k;
 
-	for (i = 0; i < 2; i++)
-		for (j = 0; j < IOPRIO_NR_LEVELS; j++)
-			if (bfqg->async_bfqq[i][j])
-				bfq_bfqq_end_wr(bfqg->async_bfqq[i][j]);
-	if (bfqg->async_idle_bfqq)
-		bfq_bfqq_end_wr(bfqg->async_idle_bfqq);
+	for (k = 0; k < bfqd->num_actuators; k++) {
+		for (i = 0; i < 2; i++)
+			for (j = 0; j < IOPRIO_NR_LEVELS; j++)
+				if (bfqg->async_bfqq[i][j][k])
+					bfq_bfqq_end_wr(bfqg->async_bfqq[i][j][k]);
+		if (bfqg->async_idle_bfqq[k])
+			bfq_bfqq_end_wr(bfqg->async_idle_bfqq[k]);
+	}
 }
 
 static void bfq_end_wr(struct bfq_data *bfqd)
 {
 	struct bfq_queue *bfqq;
+	int i;
 
 	spin_lock_irq(&bfqd->lock);
 
-	list_for_each_entry(bfqq, &bfqd->active_list, bfqq_list)
-		bfq_bfqq_end_wr(bfqq);
+	for (i = 0; i < bfqd->num_actuators; i++) {
+		list_for_each_entry(bfqq, &bfqd->active_list[i], bfqq_list)
+			bfq_bfqq_end_wr(bfqq);
+	}
 	list_for_each_entry(bfqq, &bfqd->idle_list, bfqq_list)
 		bfq_bfqq_end_wr(bfqq);
 	bfq_end_wr_async(bfqd);
@@ -2794,6 +2847,35 @@ static bool bfq_may_be_close_cooperator(struct bfq_queue *bfqq,
 static bool idling_boosts_thr_without_issues(struct bfq_data *bfqd,
 					     struct bfq_queue *bfqq);
 
+static struct bfq_queue *
+bfq_setup_stable_merge(struct bfq_data *bfqd, struct bfq_queue *bfqq,
+		       struct bfq_queue *stable_merge_bfqq,
+		       struct bfq_iocq_bfqq_data *bfqq_data)
+{
+	int proc_ref = min(bfqq_process_refs(bfqq),
+			   bfqq_process_refs(stable_merge_bfqq));
+	struct bfq_queue *new_bfqq;
+
+	if (idling_boosts_thr_without_issues(bfqd, bfqq) ||
+	    proc_ref == 0)
+		return NULL;
+
+	/* next function will take at least one ref */
+	new_bfqq = bfq_setup_merge(bfqq, stable_merge_bfqq);
+
+	if (new_bfqq) {
+		bfqq_data->stably_merged = true;
+		if (new_bfqq->bic) {
+			unsigned int new_a_idx = new_bfqq->actuator_idx;
+			struct bfq_iocq_bfqq_data *new_bfqq_data =
+				&new_bfqq->bic->bfqq_data[new_a_idx];
+
+			new_bfqq_data->stably_merged = true;
+		}
+	}
+	return new_bfqq;
+}
+
 /*
  * Attempt to schedule a merge of bfqq with the currently in-service
  * queue or with a close queue among the scheduled queues.  Return
@@ -2819,6 +2901,8 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 		     void *io_struct, bool request, struct bfq_io_cq *bic)
 {
 	struct bfq_queue *in_service_bfqq, *new_bfqq;
+	unsigned int a_idx = bfqq->actuator_idx;
+	struct bfq_iocq_bfqq_data *bfqq_data = &bic->bfqq_data[a_idx];
 
 	/* if a merge has already been setup, then proceed with that first */
 	if (bfqq->new_bfqq)
@@ -2840,37 +2924,23 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 		 * stable merging) also if bic is associated with a
 		 * sync queue, but this bfqq is async
 		 */
-		if (bfq_bfqq_sync(bfqq) && bic->stable_merge_bfqq &&
+		if (bfq_bfqq_sync(bfqq) && bfqq_data->stable_merge_bfqq &&
 		    !bfq_bfqq_just_created(bfqq) &&
 		    time_is_before_jiffies(bfqq->split_time +
 					  msecs_to_jiffies(bfq_late_stable_merging)) &&
 		    time_is_before_jiffies(bfqq->creation_time +
 					   msecs_to_jiffies(bfq_late_stable_merging))) {
 			struct bfq_queue *stable_merge_bfqq =
-				bic->stable_merge_bfqq;
-			int proc_ref = min(bfqq_process_refs(bfqq),
-					   bfqq_process_refs(stable_merge_bfqq));
+				bfqq_data->stable_merge_bfqq;
 
 			/* deschedule stable merge, because done or aborted here */
 			bfq_put_stable_ref(stable_merge_bfqq);
 
-			bic->stable_merge_bfqq = NULL;
-
-			if (!idling_boosts_thr_without_issues(bfqd, bfqq) &&
-			    proc_ref > 0) {
-				/* next function will take at least one ref */
-				struct bfq_queue *new_bfqq =
-					bfq_setup_merge(bfqq, stable_merge_bfqq);
-
-				if (new_bfqq) {
-					bic->stably_merged = true;
-					if (new_bfqq->bic)
-						new_bfqq->bic->stably_merged =
-									true;
-				}
-				return new_bfqq;
-			} else
-				return NULL;
+			bfqq_data->stable_merge_bfqq = NULL;
+
+			return bfq_setup_stable_merge(bfqd, bfqq,
+						      stable_merge_bfqq,
+						      bfqq_data);
 		}
 	}
 
@@ -2965,6 +3035,8 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
 {
 	struct bfq_io_cq *bic = bfqq->bic;
+	unsigned int a_idx = bfqq->actuator_idx;
+	struct bfq_iocq_bfqq_data *bfqq_data = &bic->bfqq_data[a_idx];
 
 	/*
 	 * If !bfqq->bic, the queue is already shared or its requests
@@ -2974,18 +3046,21 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
 	if (!bic)
 		return;
 
-	bic->saved_last_serv_time_ns = bfqq->last_serv_time_ns;
-	bic->saved_inject_limit = bfqq->inject_limit;
-	bic->saved_decrease_time_jif = bfqq->decrease_time_jif;
-
-	bic->saved_weight = bfqq->entity.orig_weight;
-	bic->saved_ttime = bfqq->ttime;
-	bic->saved_has_short_ttime = bfq_bfqq_has_short_ttime(bfqq);
-	bic->saved_IO_bound = bfq_bfqq_IO_bound(bfqq);
-	bic->saved_io_start_time = bfqq->io_start_time;
-	bic->saved_tot_idle_time = bfqq->tot_idle_time;
-	bic->saved_in_large_burst = bfq_bfqq_in_large_burst(bfqq);
-	bic->was_in_burst_list = !hlist_unhashed(&bfqq->burst_list_node);
+	bfqq_data->saved_last_serv_time_ns = bfqq->last_serv_time_ns;
+	bfqq_data->saved_inject_limit =	bfqq->inject_limit;
+	bfqq_data->saved_decrease_time_jif = bfqq->decrease_time_jif;
+
+	bfqq_data->saved_weight = bfqq->entity.orig_weight;
+	bfqq_data->saved_ttime = bfqq->ttime;
+	bfqq_data->saved_has_short_ttime =
+		bfq_bfqq_has_short_ttime(bfqq);
+	bfqq_data->saved_IO_bound = bfq_bfqq_IO_bound(bfqq);
+	bfqq_data->saved_io_start_time = bfqq->io_start_time;
+	bfqq_data->saved_tot_idle_time = bfqq->tot_idle_time;
+	bfqq_data->saved_in_large_burst = bfq_bfqq_in_large_burst(bfqq);
+	bfqq_data->was_in_burst_list =
+		!hlist_unhashed(&bfqq->burst_list_node);
+
 	if (unlikely(bfq_bfqq_just_created(bfqq) &&
 		     !bfq_bfqq_in_large_burst(bfqq) &&
 		     bfqq->bfqd->low_latency)) {
@@ -2998,17 +3073,21 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
 		 * to bfqq, so that to avoid that bfqq unjustly fails
 		 * to enjoy weight raising if split soon.
 		 */
-		bic->saved_wr_coeff = bfqq->bfqd->bfq_wr_coeff;
-		bic->saved_wr_start_at_switch_to_srt = bfq_smallest_from_now();
-		bic->saved_wr_cur_max_time = bfq_wr_duration(bfqq->bfqd);
-		bic->saved_last_wr_start_finish = jiffies;
+		bfqq_data->saved_wr_coeff = bfqq->bfqd->bfq_wr_coeff;
+		bfqq_data->saved_wr_start_at_switch_to_srt =
+			bfq_smallest_from_now();
+		bfqq_data->saved_wr_cur_max_time =
+			bfq_wr_duration(bfqq->bfqd);
+		bfqq_data->saved_last_wr_start_finish = jiffies;
 	} else {
-		bic->saved_wr_coeff = bfqq->wr_coeff;
-		bic->saved_wr_start_at_switch_to_srt =
+		bfqq_data->saved_wr_coeff = bfqq->wr_coeff;
+		bfqq_data->saved_wr_start_at_switch_to_srt =
 			bfqq->wr_start_at_switch_to_srt;
-		bic->saved_service_from_wr = bfqq->service_from_wr;
-		bic->saved_last_wr_start_finish = bfqq->last_wr_start_finish;
-		bic->saved_wr_cur_max_time = bfqq->wr_cur_max_time;
+		bfqq_data->saved_service_from_wr =
+			bfqq->service_from_wr;
+		bfqq_data->saved_last_wr_start_finish =
+			bfqq->last_wr_start_finish;
+		bfqq_data->saved_wr_cur_max_time = bfqq->wr_cur_max_time;
 	}
 }
 
@@ -3114,7 +3193,7 @@ bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic,
 	/*
 	 * Merge queues (that is, let bic redirect its requests to new_bfqq)
 	 */
-	bic_set_bfqq(bic, new_bfqq, true);
+	bic_set_bfqq(bic, new_bfqq, true, bfqq->actuator_idx);
 	bfq_mark_bfqq_coop(new_bfqq);
 	/*
 	 * new_bfqq now belongs to at least two bics (it is a shared queue):
@@ -3532,13 +3611,13 @@ static void bfq_update_peak_rate(struct bfq_data *bfqd, struct request *rq)
 	 * - start a new observation interval with this dispatch
 	 */
 	if (now_ns - bfqd->last_dispatch > 100*NSEC_PER_MSEC &&
-	    bfqd->rq_in_driver == 0)
+	    bfqd->tot_rq_in_driver == 0)
 		goto update_rate_and_reset;
 
 	/* Update sampling information */
 	bfqd->peak_rate_samples++;
 
-	if ((bfqd->rq_in_driver > 0 ||
+	if ((bfqd->tot_rq_in_driver > 0 ||
 		now_ns - bfqd->last_completion < BFQ_MIN_TT)
 	    && !BFQ_RQ_SEEKY(bfqd, bfqd->last_position, rq))
 		bfqd->sequential_samples++;
@@ -3803,10 +3882,8 @@ static bool idling_needed_for_service_guarantees(struct bfq_data *bfqd,
 		return false;
 
 	return (bfqq->wr_coeff > 1 &&
-		(bfqd->wr_busy_queues <
-		 tot_busy_queues ||
-		 bfqd->rq_in_driver >=
-		 bfqq->dispatched + 4)) ||
+		(bfqd->wr_busy_queues < tot_busy_queues ||
+		 bfqd->tot_rq_in_driver >= bfqq->dispatched + 4)) ||
 		bfq_asymmetric_scenario(bfqd, bfqq) ||
 		tot_busy_queues == 1;
 }
@@ -4072,8 +4149,7 @@ static void __bfq_bfqq_recalc_budget(struct bfq_data *bfqd,
  * function to evaluate the I/O speed of a process.
  */
 static bool bfq_bfqq_is_slow(struct bfq_data *bfqd, struct bfq_queue *bfqq,
-				 bool compensate, enum bfqq_expiration reason,
-				 unsigned long *delta_ms)
+				 bool compensate, unsigned long *delta_ms)
 {
 	ktime_t delta_ktime;
 	u32 delta_usecs;
@@ -4269,7 +4345,7 @@ void bfq_bfqq_expire(struct bfq_data *bfqd,
 	/*
 	 * Check whether the process is slow (see bfq_bfqq_is_slow).
 	 */
-	slow = bfq_bfqq_is_slow(bfqd, bfqq, compensate, reason, &delta);
+	slow = bfq_bfqq_is_slow(bfqd, bfqq, compensate, &delta);
 
 	/*
 	 * As above explained, charge slow (typically seeky) and
@@ -4577,6 +4653,8 @@ bfq_choose_bfqq_for_injection(struct bfq_data *bfqd)
 {
 	struct bfq_queue *bfqq, *in_serv_bfqq = bfqd->in_service_queue;
 	unsigned int limit = in_serv_bfqq->inject_limit;
+	int i;
+
 	/*
 	 * If
 	 * - bfqq is not weight-raised and therefore does not carry
@@ -4608,7 +4686,7 @@ bfq_choose_bfqq_for_injection(struct bfq_data *bfqd)
 		)
 		limit = 1;
 
-	if (bfqd->rq_in_driver >= limit)
+	if (bfqd->tot_rq_in_driver >= limit)
 		return NULL;
 
 	/*
@@ -4623,11 +4701,12 @@ bfq_choose_bfqq_for_injection(struct bfq_data *bfqd)
 	 *   (and re-added only if it gets new requests, but then it
 	 *   is assigned again enough budget for its new backlog).
 	 */
-	list_for_each_entry(bfqq, &bfqd->active_list, bfqq_list)
-		if (!RB_EMPTY_ROOT(&bfqq->sort_list) &&
-		    (in_serv_always_inject || bfqq->wr_coeff > 1) &&
-		    bfq_serv_to_charge(bfqq->next_rq, bfqq) <=
-		    bfq_bfqq_budget_left(bfqq)) {
+	for (i = 0; i < bfqd->num_actuators; i++) {
+		list_for_each_entry(bfqq, &bfqd->active_list[i], bfqq_list)
+			if (!RB_EMPTY_ROOT(&bfqq->sort_list) &&
+				(in_serv_always_inject || bfqq->wr_coeff > 1) &&
+				bfq_serv_to_charge(bfqq->next_rq, bfqq) <=
+				bfq_bfqq_budget_left(bfqq)) {
 			/*
 			 * Allow for only one large in-flight request
 			 * on non-rotational devices, for the
@@ -4647,27 +4726,80 @@ bfq_choose_bfqq_for_injection(struct bfq_data *bfqd)
 			 */
 			if (blk_queue_nonrot(bfqd->queue) &&
 			    blk_rq_sectors(bfqq->next_rq) >=
-			    BFQQ_SECT_THR_NONROT)
-				limit = min_t(unsigned int, 1, limit);
-			else
-				limit = in_serv_bfqq->inject_limit;
-
-			if (bfqd->rq_in_driver < limit) {
+			    BFQQ_SECT_THR_NONROT &&
+			    bfqd->tot_rq_in_driver >= 1)
+				continue;
+			else {
 				bfqd->rqs_injected = true;
 				return bfqq;
 			}
 		}
+	}
 
 	return NULL;
 }
 
+static struct bfq_queue *
+bfq_find_active_bfqq_for_actuator(struct bfq_data *bfqd, int idx)
+{
+	struct bfq_queue *bfqq;
+
+	if (bfqd->in_service_queue &&
+	    bfqd->in_service_queue->actuator_idx == idx)
+		return bfqd->in_service_queue;
+
+	list_for_each_entry(bfqq, &bfqd->active_list[idx], bfqq_list) {
+		if (!RB_EMPTY_ROOT(&bfqq->sort_list) &&
+			bfq_serv_to_charge(bfqq->next_rq, bfqq) <=
+				bfq_bfqq_budget_left(bfqq)) {
+			return bfqq;
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * Perform a linear scan of each actuator, until an actuator is found
+ * for which the following three conditions hold: the load of the
+ * actuator is below the threshold (see comments on
+ * actuator_load_threshold for details) and lower than that of the
+ * next actuator (comments on this extra condition below), and there
+ * is a queue that contains I/O for that actuator. On success, return
+ * that queue.
+ *
+ * Performing a plain linear scan entails a prioritization among
+ * actuators. The extra condition above breaks this prioritization and
+ * tends to distribute injection uniformly across actuators.
+ */
+static struct bfq_queue *
+bfq_find_bfqq_for_underused_actuator(struct bfq_data *bfqd)
+{
+	int i;
+
+	for (i = 0 ; i < bfqd->num_actuators; i++) {
+		if (bfqd->rq_in_driver[i] < bfqd->actuator_load_threshold &&
+		    (i == bfqd->num_actuators - 1 ||
+		     bfqd->rq_in_driver[i] < bfqd->rq_in_driver[i+1])) {
+			struct bfq_queue *bfqq =
+				bfq_find_active_bfqq_for_actuator(bfqd, i);
+
+			if (bfqq)
+				return bfqq;
+		}
+	}
+
+	return NULL;
+}
+
+
 /*
  * Select a queue for service.  If we have a current queue in service,
  * check whether to continue servicing it, or retrieve and set a new one.
  */
 static struct bfq_queue *bfq_select_queue(struct bfq_data *bfqd)
 {
-	struct bfq_queue *bfqq;
+	struct bfq_queue *bfqq, *inject_bfqq;
 	struct request *next_rq;
 	enum bfqq_expiration reason = BFQQE_BUDGET_TIMEOUT;
 
@@ -4690,6 +4822,15 @@ static struct bfq_queue *bfq_select_queue(struct bfq_data *bfqd)
 
 check_queue:
 	/*
+	 *  If some actuator is underutilized, but the in-service
+	 *  queue does not contain I/O for that actuator, then try to
+	 *  inject I/O for that actuator.
+	 */
+	inject_bfqq = bfq_find_bfqq_for_underused_actuator(bfqd);
+	if (inject_bfqq && inject_bfqq != bfqq)
+		return inject_bfqq;
+
+	/*
 	 * This loop is rarely executed more than once. Even when it
 	 * happens, it is much more convenient to re-execute this loop
 	 * than to return NULL and trigger a new dispatch to get a
@@ -4748,11 +4889,8 @@ check_queue:
 	 */
 	if (bfq_bfqq_wait_request(bfqq) ||
 	    (bfqq->dispatched != 0 && bfq_better_to_idle(bfqq))) {
-		struct bfq_queue *async_bfqq =
-			bfqq->bic && bfqq->bic->bfqq[0] &&
-			bfq_bfqq_busy(bfqq->bic->bfqq[0]) &&
-			bfqq->bic->bfqq[0]->next_rq ?
-			bfqq->bic->bfqq[0] : NULL;
+		unsigned int act_idx = bfqq->actuator_idx;
+		struct bfq_queue *async_bfqq = NULL;
 		struct bfq_queue *blocked_bfqq =
 			!hlist_empty(&bfqq->woken_list) ?
 			container_of(bfqq->woken_list.first,
@@ -4760,6 +4898,10 @@ check_queue:
 				     woken_list_node)
 			: NULL;
 
+		if (bfqq->bic && bfqq->bic->bfqq[0][act_idx] &&
+		    bfq_bfqq_busy(bfqq->bic->bfqq[0][act_idx]) &&
+		    bfqq->bic->bfqq[0][act_idx]->next_rq)
+			async_bfqq = bfqq->bic->bfqq[0][act_idx];
 		/*
 		 * The next four mutually-exclusive ifs decide
 		 * whether to try injection, and choose the queue to
@@ -4844,7 +4986,7 @@ check_queue:
 		    icq_to_bic(async_bfqq->next_rq->elv.icq) == bfqq->bic &&
 		    bfq_serv_to_charge(async_bfqq->next_rq, async_bfqq) <=
 		    bfq_bfqq_budget_left(async_bfqq))
-			bfqq = bfqq->bic->bfqq[0];
+			bfqq = async_bfqq;
 		else if (bfqq->waker_bfqq &&
 			   bfq_bfqq_busy(bfqq->waker_bfqq) &&
 			   bfqq->waker_bfqq->next_rq &&
@@ -4975,7 +5117,7 @@ static struct request *bfq_dispatch_rq_from_bfqq(struct bfq_data *bfqd,
 	bfq_dispatch_remove(bfqd->queue, rq);
 
 	if (bfqq != bfqd->in_service_queue)
-		goto return_rq;
+		return rq;
 
 	/*
 	 * If weight raising has to terminate for bfqq, then next
@@ -4995,12 +5137,9 @@ static struct request *bfq_dispatch_rq_from_bfqq(struct bfq_data *bfqd,
 	 * belongs to CLASS_IDLE and other queues are waiting for
 	 * service.
 	 */
-	if (!(bfq_tot_busy_queues(bfqd) > 1 && bfq_class_idle(bfqq)))
-		goto return_rq;
-
-	bfq_bfqq_expire(bfqd, bfqq, false, BFQQE_BUDGET_EXHAUSTED);
+	if (bfq_tot_busy_queues(bfqd) > 1 && bfq_class_idle(bfqq))
+		bfq_bfqq_expire(bfqd, bfqq, false, BFQQE_BUDGET_EXHAUSTED);
 
-return_rq:
 	return rq;
 }
 
@@ -5043,11 +5182,11 @@ static struct request *__bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
 
 		/*
 		 * We exploit the bfq_finish_requeue_request hook to
-		 * decrement rq_in_driver, but
+		 * decrement tot_rq_in_driver, but
 		 * bfq_finish_requeue_request will not be invoked on
 		 * this request. So, to avoid unbalance, just start
-		 * this request, without incrementing rq_in_driver. As
-		 * a negative consequence, rq_in_driver is deceptively
+		 * this request, without incrementing tot_rq_in_driver. As
+		 * a negative consequence, tot_rq_in_driver is deceptively
 		 * lower than it should be while this request is in
 		 * service. This may cause bfq_schedule_dispatch to be
 		 * invoked uselessly.
@@ -5056,7 +5195,7 @@ static struct request *__bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
 		 * bfq_finish_requeue_request hook, if defined, is
 		 * probably invoked also on this request. So, by
 		 * exploiting this hook, we could 1) increment
-		 * rq_in_driver here, and 2) decrement it in
+		 * tot_rq_in_driver here, and 2) decrement it in
 		 * bfq_finish_requeue_request. Such a solution would
 		 * let the value of the counter be always accurate,
 		 * but it would entail using an extra interface
@@ -5085,7 +5224,7 @@ static struct request *__bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
 	 * Of course, serving one request at a time may cause loss of
 	 * throughput.
 	 */
-	if (bfqd->strict_guarantees && bfqd->rq_in_driver > 0)
+	if (bfqd->strict_guarantees && bfqd->tot_rq_in_driver > 0)
 		goto exit;
 
 	bfqq = bfq_select_queue(bfqd);
@@ -5096,7 +5235,8 @@ static struct request *__bfq_dispatch_request(struct blk_mq_hw_ctx *hctx)
 
 	if (rq) {
 inc_in_driver_start_rq:
-		bfqd->rq_in_driver++;
+		bfqd->rq_in_driver[bfqq->actuator_idx]++;
+		bfqd->tot_rq_in_driver++;
 start_rq:
 		rq->rq_flags |= RQF_STARTED;
 	}
@@ -5283,8 +5423,6 @@ void bfq_put_cooperator(struct bfq_queue *bfqq)
 	 */
 	__bfqq = bfqq->new_bfqq;
 	while (__bfqq) {
-		if (__bfqq == bfqq)
-			break;
 		next = __bfqq->new_bfqq;
 		bfq_put_queue(__bfqq);
 		__bfqq = next;
@@ -5305,48 +5443,55 @@ static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq)
 	bfq_release_process_ref(bfqd, bfqq);
 }
 
-static void bfq_exit_icq_bfqq(struct bfq_io_cq *bic, bool is_sync)
+static void bfq_exit_icq_bfqq(struct bfq_io_cq *bic, bool is_sync,
+			      unsigned int actuator_idx)
 {
-	struct bfq_queue *bfqq = bic_to_bfqq(bic, is_sync);
+	struct bfq_queue *bfqq = bic_to_bfqq(bic, is_sync, actuator_idx);
 	struct bfq_data *bfqd;
 
 	if (bfqq)
 		bfqd = bfqq->bfqd; /* NULL if scheduler already exited */
 
 	if (bfqq && bfqd) {
-		unsigned long flags;
-
-		spin_lock_irqsave(&bfqd->lock, flags);
-		bic_set_bfqq(bic, NULL, is_sync);
+		bic_set_bfqq(bic, NULL, is_sync, actuator_idx);
 		bfq_exit_bfqq(bfqd, bfqq);
-		spin_unlock_irqrestore(&bfqd->lock, flags);
 	}
 }
 
 static void bfq_exit_icq(struct io_cq *icq)
 {
 	struct bfq_io_cq *bic = icq_to_bic(icq);
+	struct bfq_data *bfqd = bic_to_bfqd(bic);
+	unsigned long flags;
+	unsigned int act_idx;
+	/*
+	 * If bfqd and thus bfqd->num_actuators is not available any
+	 * longer, then cycle over all possible per-actuator bfqqs in
+	 * next loop. We rely on bic being zeroed on creation, and
+	 * therefore on its unused per-actuator fields being NULL.
+	 */
+	unsigned int num_actuators = BFQ_MAX_ACTUATORS;
+	struct bfq_iocq_bfqq_data *bfqq_data = bic->bfqq_data;
 
-	if (bic->stable_merge_bfqq) {
-		struct bfq_data *bfqd = bic->stable_merge_bfqq->bfqd;
+	/*
+	 * bfqd is NULL if scheduler already exited, and in that case
+	 * this is the last time these queues are accessed.
+	 */
+	if (bfqd) {
+		spin_lock_irqsave(&bfqd->lock, flags);
+		num_actuators = bfqd->num_actuators;
+	}
 
-		/*
-		 * bfqd is NULL if scheduler already exited, and in
-		 * that case this is the last time bfqq is accessed.
-		 */
-		if (bfqd) {
-			unsigned long flags;
+	for (act_idx = 0; act_idx < num_actuators; act_idx++) {
+		if (bfqq_data[act_idx].stable_merge_bfqq)
+			bfq_put_stable_ref(bfqq_data[act_idx].stable_merge_bfqq);
 
-			spin_lock_irqsave(&bfqd->lock, flags);
-			bfq_put_stable_ref(bic->stable_merge_bfqq);
-			spin_unlock_irqrestore(&bfqd->lock, flags);
-		} else {
-			bfq_put_stable_ref(bic->stable_merge_bfqq);
-		}
+		bfq_exit_icq_bfqq(bic, true, act_idx);
+		bfq_exit_icq_bfqq(bic, false, act_idx);
 	}
 
-	bfq_exit_icq_bfqq(bic, true);
-	bfq_exit_icq_bfqq(bic, false);
+	if (bfqd)
+		spin_unlock_irqrestore(&bfqd->lock, flags);
 }
 
 /*
@@ -5423,25 +5568,27 @@ static void bfq_check_ioprio_change(struct bfq_io_cq *bic, struct bio *bio)
 
 	bic->ioprio = ioprio;
 
-	bfqq = bic_to_bfqq(bic, false);
+	bfqq = bic_to_bfqq(bic, false, bfq_actuator_index(bfqd, bio));
 	if (bfqq) {
 		struct bfq_queue *old_bfqq = bfqq;
 
 		bfqq = bfq_get_queue(bfqd, bio, false, bic, true);
-		bic_set_bfqq(bic, bfqq, false);
+		bic_set_bfqq(bic, bfqq, false, bfq_actuator_index(bfqd, bio));
 		bfq_release_process_ref(bfqd, old_bfqq);
 	}
 
-	bfqq = bic_to_bfqq(bic, true);
+	bfqq = bic_to_bfqq(bic, true, bfq_actuator_index(bfqd, bio));
 	if (bfqq)
 		bfq_set_next_ioprio_data(bfqq, bic);
 }
 
 static void bfq_init_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq,
-			  struct bfq_io_cq *bic, pid_t pid, int is_sync)
+			  struct bfq_io_cq *bic, pid_t pid, int is_sync,
+			  unsigned int act_idx)
 {
 	u64 now_ns = ktime_get_ns();
 
+	bfqq->actuator_idx = act_idx;
 	RB_CLEAR_NODE(&bfqq->entity.rb_node);
 	INIT_LIST_HEAD(&bfqq->fifo);
 	INIT_HLIST_NODE(&bfqq->burst_list_node);
@@ -5501,22 +5648,24 @@ static void bfq_init_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 
 	/* first request is almost certainly seeky */
 	bfqq->seek_history = 1;
+
+	bfqq->decrease_time_jif = jiffies;
 }
 
 static struct bfq_queue **bfq_async_queue_prio(struct bfq_data *bfqd,
 					       struct bfq_group *bfqg,
-					       int ioprio_class, int ioprio)
+					       int ioprio_class, int ioprio, int act_idx)
 {
 	switch (ioprio_class) {
 	case IOPRIO_CLASS_RT:
-		return &bfqg->async_bfqq[0][ioprio];
+		return &bfqg->async_bfqq[0][ioprio][act_idx];
 	case IOPRIO_CLASS_NONE:
 		ioprio = IOPRIO_BE_NORM;
 		fallthrough;
 	case IOPRIO_CLASS_BE:
-		return &bfqg->async_bfqq[1][ioprio];
+		return &bfqg->async_bfqq[1][ioprio][act_idx];
 	case IOPRIO_CLASS_IDLE:
-		return &bfqg->async_idle_bfqq;
+		return &bfqg->async_idle_bfqq[act_idx];
 	default:
 		return NULL;
 	}
@@ -5527,6 +5676,7 @@ bfq_do_early_stable_merge(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 			  struct bfq_io_cq *bic,
 			  struct bfq_queue *last_bfqq_created)
 {
+	unsigned int a_idx = last_bfqq_created->actuator_idx;
 	struct bfq_queue *new_bfqq =
 		bfq_setup_merge(bfqq, last_bfqq_created);
 
@@ -5534,8 +5684,8 @@ bfq_do_early_stable_merge(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 		return bfqq;
 
 	if (new_bfqq->bic)
-		new_bfqq->bic->stably_merged = true;
-	bic->stably_merged = true;
+		new_bfqq->bic->bfqq_data[a_idx].stably_merged = true;
+	bic->bfqq_data[a_idx].stably_merged = true;
 
 	/*
 	 * Reusing merge functions. This implies that
@@ -5610,9 +5760,13 @@ static struct bfq_queue *bfq_do_or_sched_stable_merge(struct bfq_data *bfqd,
 	 * it has been set already, but too long ago, then move it
 	 * forward to bfqq. Finally, move also if bfqq belongs to a
 	 * different group than last_bfqq_created, or if bfqq has a
-	 * different ioprio or ioprio_class. If none of these
-	 * conditions holds true, then try an early stable merge or
-	 * schedule a delayed stable merge.
+	 * different ioprio, ioprio_class or actuator_idx. If none of
+	 * these conditions holds true, then try an early stable merge
+	 * or schedule a delayed stable merge. As for the condition on
+	 * actuator_idx, the reason is that, if queues associated with
+	 * different actuators are merged, then control is lost on
+	 * each actuator. Therefore some actuator may be
+	 * underutilized, and throughput may decrease.
 	 *
 	 * A delayed merge is scheduled (instead of performing an
 	 * early merge), in case bfqq might soon prove to be more
@@ -5630,7 +5784,8 @@ static struct bfq_queue *bfq_do_or_sched_stable_merge(struct bfq_data *bfqd,
 			bfqq->creation_time) ||
 		bfqq->entity.parent != last_bfqq_created->entity.parent ||
 		bfqq->ioprio != last_bfqq_created->ioprio ||
-		bfqq->ioprio_class != last_bfqq_created->ioprio_class)
+		bfqq->ioprio_class != last_bfqq_created->ioprio_class ||
+		bfqq->actuator_idx != last_bfqq_created->actuator_idx)
 		*source_bfqq = bfqq;
 	else if (time_after_eq(last_bfqq_created->creation_time +
 				 bfqd->bfq_burst_interval,
@@ -5660,7 +5815,8 @@ static struct bfq_queue *bfq_do_or_sched_stable_merge(struct bfq_data *bfqd,
 			/*
 			 * Record the bfqq to merge to.
 			 */
-			bic->stable_merge_bfqq = last_bfqq_created;
+			bic->bfqq_data[last_bfqq_created->actuator_idx].stable_merge_bfqq =
+				last_bfqq_created;
 		}
 	}
 
@@ -5682,7 +5838,8 @@ static struct bfq_queue *bfq_get_queue(struct bfq_data *bfqd,
 	bfqg = bfq_bio_bfqg(bfqd, bio);
 	if (!is_sync) {
 		async_bfqq = bfq_async_queue_prio(bfqd, bfqg, ioprio_class,
-						  ioprio);
+						  ioprio,
+						  bfq_actuator_index(bfqd, bio));
 		bfqq = *async_bfqq;
 		if (bfqq)
 			goto out;
@@ -5694,7 +5851,7 @@ static struct bfq_queue *bfq_get_queue(struct bfq_data *bfqd,
 
 	if (bfqq) {
 		bfq_init_bfqq(bfqd, bfqq, bic, current->pid,
-			      is_sync);
+			      is_sync, bfq_actuator_index(bfqd, bio));
 		bfq_init_entity(&bfqq->entity, bfqg);
 		bfq_log_bfqq(bfqd, bfqq, "allocated");
 	} else {
@@ -6009,7 +6166,8 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
 		 * then complete the merge and redirect it to
 		 * new_bfqq.
 		 */
-		if (bic_to_bfqq(RQ_BIC(rq), 1) == bfqq)
+		if (bic_to_bfqq(RQ_BIC(rq), true,
+				bfq_actuator_index(bfqd, rq->bio)) == bfqq)
 			bfq_merge_bfqqs(bfqd, RQ_BIC(rq),
 					bfqq, new_bfqq);
 
@@ -6147,7 +6305,7 @@ static void bfq_update_hw_tag(struct bfq_data *bfqd)
 	struct bfq_queue *bfqq = bfqd->in_service_queue;
 
 	bfqd->max_rq_in_driver = max_t(int, bfqd->max_rq_in_driver,
-				       bfqd->rq_in_driver);
+				       bfqd->tot_rq_in_driver);
 
 	if (bfqd->hw_tag == 1)
 		return;
@@ -6158,7 +6316,7 @@ static void bfq_update_hw_tag(struct bfq_data *bfqd)
 	 * sum is not exact, as it's not taking into account deactivated
 	 * requests.
 	 */
-	if (bfqd->rq_in_driver + bfqd->queued <= BFQ_HW_QUEUE_THRESHOLD)
+	if (bfqd->tot_rq_in_driver + bfqd->queued <= BFQ_HW_QUEUE_THRESHOLD)
 		return;
 
 	/*
@@ -6169,7 +6327,7 @@ static void bfq_update_hw_tag(struct bfq_data *bfqd)
 	if (bfqq && bfq_bfqq_has_short_ttime(bfqq) &&
 	    bfqq->dispatched + bfqq->queued[0] + bfqq->queued[1] <
 	    BFQ_HW_QUEUE_THRESHOLD &&
-	    bfqd->rq_in_driver < BFQ_HW_QUEUE_THRESHOLD)
+	    bfqd->tot_rq_in_driver < BFQ_HW_QUEUE_THRESHOLD)
 		return;
 
 	if (bfqd->hw_tag_samples++ < BFQ_HW_QUEUE_SAMPLES)
@@ -6190,7 +6348,8 @@ static void bfq_completed_request(struct bfq_queue *bfqq, struct bfq_data *bfqd)
 
 	bfq_update_hw_tag(bfqd);
 
-	bfqd->rq_in_driver--;
+	bfqd->rq_in_driver[bfqq->actuator_idx]--;
+	bfqd->tot_rq_in_driver--;
 	bfqq->dispatched--;
 
 	if (!bfqq->dispatched && !bfq_bfqq_busy(bfqq)) {
@@ -6310,7 +6469,7 @@ static void bfq_completed_request(struct bfq_queue *bfqq, struct bfq_data *bfqd)
 					BFQQE_NO_MORE_REQUESTS);
 	}
 
-	if (!bfqd->rq_in_driver)
+	if (!bfqd->tot_rq_in_driver)
 		bfq_schedule_dispatch(bfqd);
 }
 
@@ -6441,13 +6600,13 @@ static void bfq_update_inject_limit(struct bfq_data *bfqd,
 	 * conditions to do it, or we can lower the last base value
 	 * computed.
 	 *
-	 * NOTE: (bfqd->rq_in_driver == 1) means that there is no I/O
+	 * NOTE: (bfqd->tot_rq_in_driver == 1) means that there is no I/O
 	 * request in flight, because this function is in the code
 	 * path that handles the completion of a request of bfqq, and,
 	 * in particular, this function is executed before
-	 * bfqd->rq_in_driver is decremented in such a code path.
+	 * bfqd->tot_rq_in_driver is decremented in such a code path.
 	 */
-	if ((bfqq->last_serv_time_ns == 0 && bfqd->rq_in_driver == 1) ||
+	if ((bfqq->last_serv_time_ns == 0 && bfqd->tot_rq_in_driver == 1) ||
 	    tot_time_ns < bfqq->last_serv_time_ns) {
 		if (bfqq->last_serv_time_ns == 0) {
 			/*
@@ -6457,7 +6616,7 @@ static void bfq_update_inject_limit(struct bfq_data *bfqd,
 			bfqq->inject_limit = max_t(unsigned int, 1, old_limit);
 		}
 		bfqq->last_serv_time_ns = tot_time_ns;
-	} else if (!bfqd->rqs_injected && bfqd->rq_in_driver == 1)
+	} else if (!bfqd->rqs_injected && bfqd->tot_rq_in_driver == 1)
 		/*
 		 * No I/O injected and no request still in service in
 		 * the drive: these are the exact conditions for
@@ -6564,7 +6723,7 @@ bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq)
 		return bfqq;
 	}
 
-	bic_set_bfqq(bic, NULL, true);
+	bic_set_bfqq(bic, NULL, true, bfqq->actuator_idx);
 
 	bfq_put_cooperator(bfqq);
 
@@ -6578,7 +6737,9 @@ static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd,
 						   bool split, bool is_sync,
 						   bool *new_queue)
 {
-	struct bfq_queue *bfqq = bic_to_bfqq(bic, is_sync);
+	unsigned int act_idx = bfq_actuator_index(bfqd, bio);
+	struct bfq_queue *bfqq = bic_to_bfqq(bic, is_sync, act_idx);
+	struct bfq_iocq_bfqq_data *bfqq_data = &bic->bfqq_data[act_idx];
 
 	if (likely(bfqq && bfqq != &bfqd->oom_bfqq))
 		return bfqq;
@@ -6590,14 +6751,14 @@ static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd,
 		bfq_put_queue(bfqq);
 	bfqq = bfq_get_queue(bfqd, bio, is_sync, bic, split);
 
-	bic_set_bfqq(bic, bfqq, is_sync);
+	bic_set_bfqq(bic, bfqq, is_sync, act_idx);
 	if (split && is_sync) {
-		if ((bic->was_in_burst_list && bfqd->large_burst) ||
-		    bic->saved_in_large_burst)
+		if ((bfqq_data->was_in_burst_list && bfqd->large_burst) ||
+		    bfqq_data->saved_in_large_burst)
 			bfq_mark_bfqq_in_large_burst(bfqq);
 		else {
 			bfq_clear_bfqq_in_large_burst(bfqq);
-			if (bic->was_in_burst_list)
+			if (bfqq_data->was_in_burst_list)
 				/*
 				 * If bfqq was in the current
 				 * burst list before being
@@ -6686,19 +6847,20 @@ static struct bfq_queue *bfq_init_rq(struct request *rq)
 	struct bfq_queue *bfqq;
 	bool new_queue = false;
 	bool bfqq_already_existing = false, split = false;
+	unsigned int a_idx = bfq_actuator_index(bfqd, bio);
 
 	if (unlikely(!rq->elv.icq))
 		return NULL;
 
 	/*
-	 * Assuming that elv.priv[1] is set only if everything is set
+	 * Assuming that RQ_BFQQ(rq) is set only if everything is set
 	 * for this rq. This holds true, because this function is
 	 * invoked only for insertion or merging, and, after such
 	 * events, a request cannot be manipulated any longer before
 	 * being removed from bfq.
 	 */
-	if (rq->elv.priv[1])
-		return rq->elv.priv[1];
+	if (RQ_BFQQ(rq))
+		return RQ_BFQQ(rq);
 
 	bic = icq_to_bic(rq->elv.icq);
 
@@ -6712,12 +6874,13 @@ static struct bfq_queue *bfq_init_rq(struct request *rq)
 	if (likely(!new_queue)) {
 		/* If the queue was seeky for too long, break it apart. */
 		if (bfq_bfqq_coop(bfqq) && bfq_bfqq_split_coop(bfqq) &&
-			!bic->stably_merged) {
+			!bic->bfqq_data[a_idx].stably_merged) {
 			struct bfq_queue *old_bfqq = bfqq;
 
 			/* Update bic before losing reference to bfqq */
 			if (bfq_bfqq_in_large_burst(bfqq))
-				bic->saved_in_large_burst = true;
+				bic->bfqq_data[a_idx].saved_in_large_burst =
+					true;
 
 			bfqq = bfq_split_bfqq(bic, bfqq);
 			split = true;
@@ -6900,13 +7063,15 @@ static void __bfq_put_async_bfqq(struct bfq_data *bfqd,
  */
 void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg)
 {
-	int i, j;
+	int i, j, k;
 
-	for (i = 0; i < 2; i++)
-		for (j = 0; j < IOPRIO_NR_LEVELS; j++)
-			__bfq_put_async_bfqq(bfqd, &bfqg->async_bfqq[i][j]);
+	for (k = 0; k < bfqd->num_actuators; k++) {
+		for (i = 0; i < 2; i++)
+			for (j = 0; j < IOPRIO_NR_LEVELS; j++)
+				__bfq_put_async_bfqq(bfqd, &bfqg->async_bfqq[i][j][k]);
 
-	__bfq_put_async_bfqq(bfqd, &bfqg->async_idle_bfqq);
+		__bfq_put_async_bfqq(bfqd, &bfqg->async_idle_bfqq[k]);
+	}
 }
 
 /*
@@ -6983,7 +7148,7 @@ static void bfq_exit_queue(struct elevator_queue *e)
 	bfqg_and_blkg_put(bfqd->root_group);
 
 #ifdef CONFIG_BFQ_GROUP_IOSCHED
-	blkcg_deactivate_policy(bfqd->queue, &blkcg_policy_bfq);
+	blkcg_deactivate_policy(bfqd->queue->disk, &blkcg_policy_bfq);
 #else
 	spin_lock_irq(&bfqd->lock);
 	bfq_put_async_queues(bfqd, bfqd->root_group);
@@ -6993,7 +7158,7 @@ static void bfq_exit_queue(struct elevator_queue *e)
 
 	blk_stat_disable_accounting(bfqd->queue);
 	clear_bit(ELEVATOR_FLAG_DISABLE_WBT, &e->flags);
-	wbt_enable_default(bfqd->queue);
+	wbt_enable_default(bfqd->queue->disk);
 
 	kfree(bfqd);
 }
@@ -7018,6 +7183,8 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 {
 	struct bfq_data *bfqd;
 	struct elevator_queue *eq;
+	unsigned int i;
+	struct blk_independent_access_ranges *ia_ranges = q->disk->ia_ranges;
 
 	eq = elevator_alloc(q, e);
 	if (!eq)
@@ -7038,8 +7205,10 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 	 * Our fallback bfqq if bfq_find_alloc_queue() runs into OOM issues.
 	 * Grab a permanent reference to it, so that the normal code flow
 	 * will not attempt to free it.
+	 * Set zero as actuator index: we will pretend that
+	 * all I/O requests are for the same actuator.
 	 */
-	bfq_init_bfqq(bfqd, &bfqd->oom_bfqq, NULL, 1, 0);
+	bfq_init_bfqq(bfqd, &bfqd->oom_bfqq, NULL, 1, 0, 0);
 	bfqd->oom_bfqq.ref++;
 	bfqd->oom_bfqq.new_ioprio = BFQ_DEFAULT_QUEUE_IOPRIO;
 	bfqd->oom_bfqq.new_ioprio_class = IOPRIO_CLASS_BE;
@@ -7058,6 +7227,39 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 
 	bfqd->queue = q;
 
+	bfqd->num_actuators = 1;
+	/*
+	 * If the disk supports multiple actuators, copy independent
+	 * access ranges from the request queue structure.
+	 */
+	spin_lock_irq(&q->queue_lock);
+	if (ia_ranges) {
+		/*
+		 * Check if the disk ia_ranges size exceeds the current bfq
+		 * actuator limit.
+		 */
+		if (ia_ranges->nr_ia_ranges > BFQ_MAX_ACTUATORS) {
+			pr_crit("nr_ia_ranges higher than act limit: iars=%d, max=%d.\n",
+				ia_ranges->nr_ia_ranges, BFQ_MAX_ACTUATORS);
+			pr_crit("Falling back to single actuator mode.\n");
+		} else {
+			bfqd->num_actuators = ia_ranges->nr_ia_ranges;
+
+			for (i = 0; i < bfqd->num_actuators; i++) {
+				bfqd->sector[i] = ia_ranges->ia_range[i].sector;
+				bfqd->nr_sectors[i] =
+					ia_ranges->ia_range[i].nr_sectors;
+			}
+		}
+	}
+
+	/* Otherwise use single-actuator dev info */
+	if (bfqd->num_actuators == 1) {
+		bfqd->sector[0] = 0;
+		bfqd->nr_sectors[0] = get_capacity(q->disk);
+	}
+	spin_unlock_irq(&q->queue_lock);
+
 	INIT_LIST_HEAD(&bfqd->dispatch);
 
 	hrtimer_init(&bfqd->idle_slice_timer, CLOCK_MONOTONIC,
@@ -7069,7 +7271,8 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 	bfqd->num_groups_with_pending_reqs = 0;
 #endif
 
-	INIT_LIST_HEAD(&bfqd->active_list);
+	INIT_LIST_HEAD(&bfqd->active_list[0]);
+	INIT_LIST_HEAD(&bfqd->active_list[1]);
 	INIT_LIST_HEAD(&bfqd->idle_list);
 	INIT_HLIST_HEAD(&bfqd->burst_list);
 
@@ -7095,7 +7298,6 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 	 */
 	bfqd->bfq_wr_coeff = 30;
 	bfqd->bfq_wr_rt_max_time = msecs_to_jiffies(300);
-	bfqd->bfq_wr_max_time = 0;
 	bfqd->bfq_wr_min_idle_time = msecs_to_jiffies(2000);
 	bfqd->bfq_wr_min_inter_arr_async = msecs_to_jiffies(500);
 	bfqd->bfq_wr_max_softrt_rate = 7000; /*
@@ -7114,6 +7316,9 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 		ref_wr_duration[blk_queue_nonrot(bfqd->queue)];
 	bfqd->peak_rate = ref_rate[blk_queue_nonrot(bfqd->queue)] * 2 / 3;
 
+	/* see comments on the definition of next field inside bfq_data */
+	bfqd->actuator_load_threshold = 4;
+
 	spin_lock_init(&bfqd->lock);
 
 	/*
@@ -7141,7 +7346,7 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
 	blk_queue_flag_set(QUEUE_FLAG_SQ_SCHED, q);
 
 	set_bit(ELEVATOR_FLAG_DISABLE_WBT, &eq->flags);
-	wbt_disable_default(q);
+	wbt_disable_default(q->disk);
 	blk_stat_enable_accounting(q);
 
 	return 0;
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index 466e4865ace6..69aaee52285a 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -33,6 +33,14 @@
  */
 #define BFQ_SOFTRT_WEIGHT_FACTOR	100
 
+/*
+ * Maximum number of actuators supported. This constant is used simply
+ * to define the size of the static array that will contain
+ * per-actuator data. The current value is hopefully a good upper
+ * bound to the possible number of actuators of any actual drive.
+ */
+#define BFQ_MAX_ACTUATORS 8
+
 struct bfq_entity;
 
 /**
@@ -227,12 +235,14 @@ struct bfq_ttime {
  * struct bfq_queue - leaf schedulable entity.
  *
  * A bfq_queue is a leaf request queue; it can be associated with an
- * io_context or more, if it  is  async or shared  between  cooperating
- * processes. @cgroup holds a reference to the cgroup, to be sure that it
- * does not disappear while a bfqq still references it (mostly to avoid
- * races between request issuing and task migration followed by cgroup
- * destruction).
- * All the fields are protected by the queue lock of the containing bfqd.
+ * io_context or more, if it is async or shared between cooperating
+ * processes. Besides, it contains I/O requests for only one actuator
+ * (an io_context is associated with a different bfq_queue for each
+ * actuator it generates I/O for). @cgroup holds a reference to the
+ * cgroup, to be sure that it does not disappear while a bfqq still
+ * references it (mostly to avoid races between request issuing and
+ * task migration followed by cgroup destruction).  All the fields are
+ * protected by the queue lock of the containing bfqd.
  */
 struct bfq_queue {
 	/* reference counter */
@@ -397,24 +407,18 @@ struct bfq_queue {
 	 * the woken queues when this queue exits.
 	 */
 	struct hlist_head woken_list;
+
+	/* index of the actuator this queue is associated with */
+	unsigned int actuator_idx;
 };
 
 /**
- * struct bfq_io_cq - per (request_queue, io_context) structure.
- */
-struct bfq_io_cq {
-	/* associated io_cq structure */
-	struct io_cq icq; /* must be the first member */
-	/* array of two process queues, the sync and the async */
-	struct bfq_queue *bfqq[2];
-	/* per (request_queue, blkcg) ioprio */
-	int ioprio;
-#ifdef CONFIG_BFQ_GROUP_IOSCHED
-	uint64_t blkcg_serial_nr; /* the current blkcg serial */
-#endif
+* struct bfq_data - bfqq data unique and persistent for associated bfq_io_cq
+*/
+struct bfq_iocq_bfqq_data {
 	/*
 	 * Snapshot of the has_short_time flag before merging; taken
-	 * to remember its value while the queue is merged, so as to
+	 * to remember its values while the queue is merged, so as to
 	 * be able to restore it in case of split.
 	 */
 	bool saved_has_short_ttime;
@@ -428,7 +432,7 @@ struct bfq_io_cq {
 	u64 saved_tot_idle_time;
 
 	/*
-	 * Same purpose as the previous fields for the value of the
+	 * Same purpose as the previous fields for the values of the
 	 * field keeping the queue's belonging to a large burst
 	 */
 	bool saved_in_large_burst;
@@ -466,6 +470,38 @@ struct bfq_io_cq {
 	struct bfq_queue *stable_merge_bfqq;
 
 	bool stably_merged;	/* non splittable if true */
+};
+
+/**
+ * struct bfq_io_cq - per (request_queue, io_context) structure.
+ */
+struct bfq_io_cq {
+	/* associated io_cq structure */
+	struct io_cq icq; /* must be the first member */
+	/*
+	 * Matrix of associated process queues: first row for async
+	 * queues, second row sync queues. Each row contains one
+	 * column for each actuator. An I/O request generated by the
+	 * process is inserted into the queue pointed by bfqq[i][j] if
+	 * the request is to be served by the j-th actuator of the
+	 * drive, where i==0 or i==1, depending on whether the request
+	 * is async or sync. So there is a distinct queue for each
+	 * actuator.
+	 */
+	struct bfq_queue *bfqq[2][BFQ_MAX_ACTUATORS];
+	/* per (request_queue, blkcg) ioprio */
+	int ioprio;
+#ifdef CONFIG_BFQ_GROUP_IOSCHED
+	uint64_t blkcg_serial_nr; /* the current blkcg serial */
+#endif
+
+	/*
+	 * Persistent data for associated synchronous process queues
+	 * (one queue per actuator, see field bfqq above). In
+	 * particular, each of these queues may undergo a merge.
+	 */
+	struct bfq_iocq_bfqq_data bfqq_data[BFQ_MAX_ACTUATORS];
+
 	unsigned int requests;	/* Number of requests this process has in flight */
 };
 
@@ -554,7 +590,12 @@ struct bfq_data {
 	/* number of queued requests */
 	int queued;
 	/* number of requests dispatched and waiting for completion */
-	int rq_in_driver;
+	int tot_rq_in_driver;
+	/*
+	 * number of requests dispatched and waiting for completion
+	 * for each actuator
+	 */
+	int rq_in_driver[BFQ_MAX_ACTUATORS];
 
 	/* true if the device is non rotational and performs queueing */
 	bool nonrot_with_queueing;
@@ -648,8 +689,13 @@ struct bfq_data {
 	/* maximum budget allotted to a bfq_queue before rescheduling */
 	int bfq_max_budget;
 
-	/* list of all the bfq_queues active on the device */
-	struct list_head active_list;
+	/*
+	 * List of all the bfq_queues active for a specific actuator
+	 * on the device. Keeping active queues separate on a
+	 * per-actuator basis helps implementing per-actuator
+	 * injection more efficiently.
+	 */
+	struct list_head active_list[BFQ_MAX_ACTUATORS];
 	/* list of all the bfq_queues idle on the device */
 	struct list_head idle_list;
 
@@ -723,8 +769,6 @@ struct bfq_data {
 	 * is multiplied.
 	 */
 	unsigned int bfq_wr_coeff;
-	/* maximum duration of a weight-raising period (jiffies) */
-	unsigned int bfq_wr_max_time;
 
 	/* Maximum weight-raising duration for soft real-time processes */
 	unsigned int bfq_wr_rt_max_time;
@@ -772,6 +816,42 @@ struct bfq_data {
 	 */
 	unsigned int word_depths[2][2];
 	unsigned int full_depth_shift;
+
+	/*
+	 * Number of independent actuators. This is equal to 1 in
+	 * case of single-actuator drives.
+	 */
+	unsigned int num_actuators;
+	/*
+	 * Disk independent access ranges for each actuator
+	 * in this device.
+	 */
+	sector_t sector[BFQ_MAX_ACTUATORS];
+	sector_t nr_sectors[BFQ_MAX_ACTUATORS];
+	struct blk_independent_access_range ia_ranges[BFQ_MAX_ACTUATORS];
+
+	/*
+	 * If the number of I/O requests queued in the device for a
+	 * given actuator is below next threshold, then the actuator
+	 * is deemed as underutilized. If this condition is found to
+	 * hold for some actuator upon a dispatch, but (i) the
+	 * in-service queue does not contain I/O for that actuator,
+	 * while (ii) some other queue does contain I/O for that
+	 * actuator, then the head I/O request of the latter queue is
+	 * returned (injected), instead of the head request of the
+	 * currently in-service queue.
+	 *
+	 * We set the threshold, empirically, to the minimum possible
+	 * value for which an actuator is fully utilized, or close to
+	 * be fully utilized. By doing so, injected I/O 'steals' as
+	 * few drive-queue slots as possibile to the in-service
+	 * queue. This reduces as much as possible the probability
+	 * that the service of I/O from the in-service bfq_queue gets
+	 * delayed because of slot exhaustion, i.e., because all the
+	 * slots of the drive queue are filled with I/O injected from
+	 * other queues (NCQ provides for 32 slots).
+	 */
+	unsigned int actuator_load_threshold;
 };
 
 enum bfqq_state_flags {
@@ -929,16 +1009,14 @@ struct bfq_group {
 
 	/* reference counter (see comments in bfq_bic_update_cgroup) */
 	refcount_t ref;
-	/* Is bfq_group still online? */
-	bool online;
 
 	struct bfq_entity entity;
 	struct bfq_sched_data sched_data;
 
 	struct bfq_data *bfqd;
 
-	struct bfq_queue *async_bfqq[2][IOPRIO_NR_LEVELS];
-	struct bfq_queue *async_idle_bfqq;
+	struct bfq_queue *async_bfqq[2][IOPRIO_NR_LEVELS][BFQ_MAX_ACTUATORS];
+	struct bfq_queue *async_idle_bfqq[BFQ_MAX_ACTUATORS];
 
 	struct bfq_entity *my_entity;
 
@@ -955,8 +1033,8 @@ struct bfq_group {
 	struct bfq_entity entity;
 	struct bfq_sched_data sched_data;
 
-	struct bfq_queue *async_bfqq[2][IOPRIO_NR_LEVELS];
-	struct bfq_queue *async_idle_bfqq;
+	struct bfq_queue *async_bfqq[2][IOPRIO_NR_LEVELS][BFQ_MAX_ACTUATORS];
+	struct bfq_queue *async_idle_bfqq[BFQ_MAX_ACTUATORS];
 
 	struct rb_root rq_pos_tree;
 };
@@ -969,8 +1047,10 @@ struct bfq_group {
 
 extern const int bfq_timeout;
 
-struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync);
-void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync);
+struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync,
+				unsigned int actuator_idx);
+void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync,
+				unsigned int actuator_idx);
 struct bfq_data *bic_to_bfqd(struct bfq_io_cq *bic);
 void bfq_pos_tree_add_move(struct bfq_data *bfqd, struct bfq_queue *bfqq);
 void bfq_weights_tree_add(struct bfq_queue *bfqq);
diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c
index ea4c3d757fdd..7941b6f07391 100644
--- a/block/bfq-wf2q.c
+++ b/block/bfq-wf2q.c
@@ -493,7 +493,7 @@ static void bfq_active_insert(struct bfq_service_tree *st,
 	bfq_update_active_tree(node);
 
 	if (bfqq)
-		list_add(&bfqq->bfqq_list, &bfqq->bfqd->active_list);
+		list_add(&bfqq->bfqq_list, &bfqq->bfqd->active_list[bfqq->actuator_idx]);
 
 	bfq_inc_active_entities(entity);
 }
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 3f5685c00e36..4533eb491661 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -124,23 +124,18 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
 			   unsigned int len, unsigned int offset)
 {
 	struct bio_integrity_payload *bip = bio_integrity(bio);
-	struct bio_vec *iv;
 
 	if (bip->bip_vcnt >= bip->bip_max_vcnt) {
 		printk(KERN_ERR "%s: bip_vec full\n", __func__);
 		return 0;
 	}
 
-	iv = bip->bip_vec + bip->bip_vcnt;
-
 	if (bip->bip_vcnt &&
 	    bvec_gap_to_prev(&bdev_get_queue(bio->bi_bdev)->limits,
 			     &bip->bip_vec[bip->bip_vcnt - 1], offset))
 		return 0;
 
-	iv->bv_page = page;
-	iv->bv_len = len;
-	iv->bv_offset = offset;
+	bvec_set_page(&bip->bip_vec[bip->bip_vcnt], page, len, offset);
 	bip->bip_vcnt++;
 
 	return len;
@@ -418,6 +413,7 @@ int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
 
 	bip->bip_vcnt = bip_src->bip_vcnt;
 	bip->bip_iter = bip_src->bip_iter;
+	bip->bip_flags = bip_src->bip_flags & ~BIP_BLOCK_INTEGRITY;
 
 	return 0;
 }
diff --git a/block/bio.c b/block/bio.c
index ab59a491a883..2693f34afb7e 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -26,7 +26,6 @@
 #include "blk-cgroup.h"
 
 #define ALLOC_CACHE_THRESHOLD	16
-#define ALLOC_CACHE_SLACK	64
 #define ALLOC_CACHE_MAX		256
 
 struct bio_alloc_cache {
@@ -1029,10 +1028,7 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 	if (bio->bi_vcnt >= queue_max_segments(q))
 		return 0;
 
-	bvec = &bio->bi_io_vec[bio->bi_vcnt];
-	bvec->bv_page = page;
-	bvec->bv_len = len;
-	bvec->bv_offset = offset;
+	bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, offset);
 	bio->bi_vcnt++;
 	bio->bi_iter.bi_size += len;
 	return len;
@@ -1108,15 +1104,10 @@ EXPORT_SYMBOL_GPL(bio_add_zone_append_page);
 void __bio_add_page(struct bio *bio, struct page *page,
 		unsigned int len, unsigned int off)
 {
-	struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt];
-
 	WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
 	WARN_ON_ONCE(bio_full(bio, len));
 
-	bv->bv_page = page;
-	bv->bv_offset = off;
-	bv->bv_len = len;
-
+	bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, off);
 	bio->bi_iter.bi_size += len;
 	bio->bi_vcnt++;
 }
@@ -1792,6 +1783,8 @@ static int __init init_bio(void)
 {
 	int i;
 
+	BUILD_BUG_ON(BIO_FLAG_LAST > 8 * sizeof_field(struct bio, bi_flags));
+
 	bio_integrity_init();
 
 	for (i = 0; i < ARRAY_SIZE(bvec_slabs); i++) {
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 9ac1efb053e0..bd50b55bdb61 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -118,14 +118,26 @@ static void blkg_free_workfn(struct work_struct *work)
 {
 	struct blkcg_gq *blkg = container_of(work, struct blkcg_gq,
 					     free_work);
+	struct request_queue *q = blkg->q;
 	int i;
 
+	/*
+	 * pd_free_fn() can also be called from blkcg_deactivate_policy(),
+	 * in order to make sure pd_free_fn() is called in order, the deletion
+	 * of the list blkg->q_node is delayed to here from blkg_destroy(), and
+	 * blkcg_mutex is used to synchronize blkg_free_workfn() and
+	 * blkcg_deactivate_policy().
+	 */
+	mutex_lock(&q->blkcg_mutex);
 	for (i = 0; i < BLKCG_MAX_POLS; i++)
 		if (blkg->pd[i])
 			blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
+	if (blkg->parent)
+		blkg_put(blkg->parent);
+	list_del_init(&blkg->q_node);
+	mutex_unlock(&q->blkcg_mutex);
 
-	if (blkg->q)
-		blk_put_queue(blkg->q);
+	blk_put_queue(q);
 	free_percpu(blkg->iostat_cpu);
 	percpu_ref_exit(&blkg->refcnt);
 	kfree(blkg);
@@ -158,8 +170,6 @@ static void __blkg_release(struct rcu_head *rcu)
 
 	/* release the blkcg and parent blkg refs this blkg has been holding */
 	css_put(&blkg->blkcg->css);
-	if (blkg->parent)
-		blkg_put(blkg->parent);
 	blkg_free(blkg);
 }
 
@@ -249,16 +259,13 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct gendisk *disk,
 	blkg = kzalloc_node(sizeof(*blkg), gfp_mask, disk->queue->node);
 	if (!blkg)
 		return NULL;
-
 	if (percpu_ref_init(&blkg->refcnt, blkg_release, 0, gfp_mask))
-		goto err_free;
-
+		goto out_free_blkg;
 	blkg->iostat_cpu = alloc_percpu_gfp(struct blkg_iostat_set, gfp_mask);
 	if (!blkg->iostat_cpu)
-		goto err_free;
-
+		goto out_exit_refcnt;
 	if (!blk_get_queue(disk->queue))
-		goto err_free;
+		goto out_free_iostat;
 
 	blkg->q = disk->queue;
 	INIT_LIST_HEAD(&blkg->q_node);
@@ -281,19 +288,28 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct gendisk *disk,
 			continue;
 
 		/* alloc per-policy data and attach it to blkg */
-		pd = pol->pd_alloc_fn(gfp_mask, disk->queue, blkcg);
+		pd = pol->pd_alloc_fn(disk, blkcg, gfp_mask);
 		if (!pd)
-			goto err_free;
-
+			goto out_free_pds;
 		blkg->pd[i] = pd;
 		pd->blkg = blkg;
 		pd->plid = i;
+		pd->online = false;
 	}
 
 	return blkg;
 
-err_free:
-	blkg_free(blkg);
+out_free_pds:
+	while (--i >= 0)
+		if (blkg->pd[i])
+			blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
+	blk_put_queue(disk->queue);
+out_free_iostat:
+	free_percpu(blkg->iostat_cpu);
+out_exit_refcnt:
+	percpu_ref_exit(&blkg->refcnt);
+out_free_blkg:
+	kfree(blkg);
 	return NULL;
 }
 
@@ -359,8 +375,11 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, struct gendisk *disk,
 		for (i = 0; i < BLKCG_MAX_POLS; i++) {
 			struct blkcg_policy *pol = blkcg_policy[i];
 
-			if (blkg->pd[i] && pol->pd_online_fn)
-				pol->pd_online_fn(blkg->pd[i]);
+			if (blkg->pd[i]) {
+				if (pol->pd_online_fn)
+					pol->pd_online_fn(blkg->pd[i]);
+				blkg->pd[i]->online = true;
+			}
 		}
 	}
 	blkg->online = true;
@@ -376,7 +395,8 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, struct gendisk *disk,
 err_put_css:
 	css_put(&blkcg->css);
 err_free_blkg:
-	blkg_free(new_blkg);
+	if (new_blkg)
+		blkg_free(new_blkg);
 	return ERR_PTR(ret);
 }
 
@@ -458,21 +478,28 @@ static void blkg_destroy(struct blkcg_gq *blkg)
 	lockdep_assert_held(&blkg->q->queue_lock);
 	lockdep_assert_held(&blkcg->lock);
 
-	/* Something wrong if we are trying to remove same group twice */
-	WARN_ON_ONCE(list_empty(&blkg->q_node));
-	WARN_ON_ONCE(hlist_unhashed(&blkg->blkcg_node));
+	/*
+	 * blkg stays on the queue list until blkg_free_workfn(), see details in
+	 * blkg_free_workfn(), hence this function can be called from
+	 * blkcg_destroy_blkgs() first and again from blkg_destroy_all() before
+	 * blkg_free_workfn().
+	 */
+	if (hlist_unhashed(&blkg->blkcg_node))
+		return;
 
 	for (i = 0; i < BLKCG_MAX_POLS; i++) {
 		struct blkcg_policy *pol = blkcg_policy[i];
 
-		if (blkg->pd[i] && pol->pd_offline_fn)
-			pol->pd_offline_fn(blkg->pd[i]);
+		if (blkg->pd[i] && blkg->pd[i]->online) {
+			blkg->pd[i]->online = false;
+			if (pol->pd_offline_fn)
+				pol->pd_offline_fn(blkg->pd[i]);
+		}
 	}
 
 	blkg->online = false;
 
 	radix_tree_delete(&blkcg->blkg_tree, blkg->q->id);
-	list_del_init(&blkg->q_node);
 	hlist_del_init_rcu(&blkg->blkcg_node);
 
 	/*
@@ -559,7 +586,7 @@ static int blkcg_reset_stats(struct cgroup_subsys_state *css,
 
 const char *blkg_dev_name(struct blkcg_gq *blkg)
 {
-	if (!blkg->q->disk || !blkg->q->disk->bdi->dev)
+	if (!blkg->q->disk)
 		return NULL;
 	return bdi_dev_name(blkg->q->disk->bdi);
 }
@@ -1273,6 +1300,7 @@ int blkcg_init_disk(struct gendisk *disk)
 	int ret;
 
 	INIT_LIST_HEAD(&q->blkg_list);
+	mutex_init(&q->blkcg_mutex);
 
 	new_blkg = blkg_alloc(&blkcg_root, disk, GFP_KERNEL);
 	if (!new_blkg)
@@ -1349,9 +1377,9 @@ static void blkcg_bind(struct cgroup_subsys_state *root_css)
 
 static void blkcg_exit(struct task_struct *tsk)
 {
-	if (tsk->throttle_queue)
-		blk_put_queue(tsk->throttle_queue);
-	tsk->throttle_queue = NULL;
+	if (tsk->throttle_disk)
+		put_disk(tsk->throttle_disk);
+	tsk->throttle_disk = NULL;
 }
 
 struct cgroup_subsys io_cgrp_subsys = {
@@ -1377,14 +1405,14 @@ struct cgroup_subsys io_cgrp_subsys = {
 EXPORT_SYMBOL_GPL(io_cgrp_subsys);
 
 /**
- * blkcg_activate_policy - activate a blkcg policy on a request_queue
- * @q: request_queue of interest
+ * blkcg_activate_policy - activate a blkcg policy on a gendisk
+ * @disk: gendisk of interest
  * @pol: blkcg policy to activate
  *
- * Activate @pol on @q.  Requires %GFP_KERNEL context.  @q goes through
+ * Activate @pol on @disk.  Requires %GFP_KERNEL context.  @disk goes through
  * bypass mode to populate its blkgs with policy_data for @pol.
  *
- * Activation happens with @q bypassed, so nobody would be accessing blkgs
+ * Activation happens with @disk bypassed, so nobody would be accessing blkgs
  * from IO path.  Update of each blkg is protected by both queue and blkcg
  * locks so that holding either lock and testing blkcg_policy_enabled() is
  * always enough for dereferencing policy data.
@@ -1392,9 +1420,9 @@ EXPORT_SYMBOL_GPL(io_cgrp_subsys);
  * The caller is responsible for synchronizing [de]activations and policy
  * [un]registerations.  Returns 0 on success, -errno on failure.
  */
-int blkcg_activate_policy(struct request_queue *q,
-			  const struct blkcg_policy *pol)
+int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol)
 {
+	struct request_queue *q = disk->queue;
 	struct blkg_policy_data *pd_prealloc = NULL;
 	struct blkcg_gq *blkg, *pinned_blkg = NULL;
 	int ret;
@@ -1419,8 +1447,8 @@ retry:
 			pd = pd_prealloc;
 			pd_prealloc = NULL;
 		} else {
-			pd = pol->pd_alloc_fn(GFP_NOWAIT | __GFP_NOWARN, q,
-					      blkg->blkcg);
+			pd = pol->pd_alloc_fn(disk, blkg->blkcg,
+					      GFP_NOWAIT | __GFP_NOWARN);
 		}
 
 		if (!pd) {
@@ -1437,8 +1465,8 @@ retry:
 
 			if (pd_prealloc)
 				pol->pd_free_fn(pd_prealloc);
-			pd_prealloc = pol->pd_alloc_fn(GFP_KERNEL, q,
-						       blkg->blkcg);
+			pd_prealloc = pol->pd_alloc_fn(disk, blkg->blkcg,
+						       GFP_KERNEL);
 			if (pd_prealloc)
 				goto retry;
 			else
@@ -1448,6 +1476,7 @@ retry:
 		blkg->pd[pol->plid] = pd;
 		pd->blkg = blkg;
 		pd->plid = pol->plid;
+		pd->online = false;
 	}
 
 	/* all allocated, init in the same order */
@@ -1455,9 +1484,11 @@ retry:
 		list_for_each_entry_reverse(blkg, &q->blkg_list, q_node)
 			pol->pd_init_fn(blkg->pd[pol->plid]);
 
-	if (pol->pd_online_fn)
-		list_for_each_entry_reverse(blkg, &q->blkg_list, q_node)
+	list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) {
+		if (pol->pd_online_fn)
 			pol->pd_online_fn(blkg->pd[pol->plid]);
+		blkg->pd[pol->plid]->online = true;
+	}
 
 	__set_bit(pol->plid, q->blkcg_pols);
 	ret = 0;
@@ -1492,16 +1523,17 @@ enomem:
 EXPORT_SYMBOL_GPL(blkcg_activate_policy);
 
 /**
- * blkcg_deactivate_policy - deactivate a blkcg policy on a request_queue
- * @q: request_queue of interest
+ * blkcg_deactivate_policy - deactivate a blkcg policy on a gendisk
+ * @disk: gendisk of interest
  * @pol: blkcg policy to deactivate
  *
- * Deactivate @pol on @q.  Follows the same synchronization rules as
+ * Deactivate @pol on @disk.  Follows the same synchronization rules as
  * blkcg_activate_policy().
  */
-void blkcg_deactivate_policy(struct request_queue *q,
+void blkcg_deactivate_policy(struct gendisk *disk,
 			     const struct blkcg_policy *pol)
 {
+	struct request_queue *q = disk->queue;
 	struct blkcg_gq *blkg;
 
 	if (!blkcg_policy_enabled(q, pol))
@@ -1510,6 +1542,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
 	if (queue_is_mq(q))
 		blk_mq_freeze_queue(q);
 
+	mutex_lock(&q->blkcg_mutex);
 	spin_lock_irq(&q->queue_lock);
 
 	__clear_bit(pol->plid, q->blkcg_pols);
@@ -1519,7 +1552,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
 
 		spin_lock(&blkcg->lock);
 		if (blkg->pd[pol->plid]) {
-			if (pol->pd_offline_fn)
+			if (blkg->pd[pol->plid]->online && pol->pd_offline_fn)
 				pol->pd_offline_fn(blkg->pd[pol->plid]);
 			pol->pd_free_fn(blkg->pd[pol->plid]);
 			blkg->pd[pol->plid] = NULL;
@@ -1528,6 +1561,7 @@ void blkcg_deactivate_policy(struct request_queue *q,
 	}
 
 	spin_unlock_irq(&q->queue_lock);
+	mutex_unlock(&q->blkcg_mutex);
 
 	if (queue_is_mq(q))
 		blk_mq_unfreeze_queue(q);
@@ -1797,29 +1831,29 @@ static void blkcg_maybe_throttle_blkg(struct blkcg_gq *blkg, bool use_memdelay)
  *
  * This is only called if we've been marked with set_notify_resume().  Obviously
  * we can be set_notify_resume() for reasons other than blkcg throttling, so we
- * check to see if current->throttle_queue is set and if not this doesn't do
+ * check to see if current->throttle_disk is set and if not this doesn't do
  * anything.  This should only ever be called by the resume code, it's not meant
  * to be called by people willy-nilly as it will actually do the work to
  * throttle the task if it is setup for throttling.
  */
 void blkcg_maybe_throttle_current(void)
 {
-	struct request_queue *q = current->throttle_queue;
+	struct gendisk *disk = current->throttle_disk;
 	struct blkcg *blkcg;
 	struct blkcg_gq *blkg;
 	bool use_memdelay = current->use_memdelay;
 
-	if (!q)
+	if (!disk)
 		return;
 
-	current->throttle_queue = NULL;
+	current->throttle_disk = NULL;
 	current->use_memdelay = false;
 
 	rcu_read_lock();
 	blkcg = css_to_blkcg(blkcg_css());
 	if (!blkcg)
 		goto out;
-	blkg = blkg_lookup(blkcg, q);
+	blkg = blkg_lookup(blkcg, disk->queue);
 	if (!blkg)
 		goto out;
 	if (!blkg_tryget(blkg))
@@ -1828,11 +1862,10 @@ void blkcg_maybe_throttle_current(void)
 
 	blkcg_maybe_throttle_blkg(blkg, use_memdelay);
 	blkg_put(blkg);
-	blk_put_queue(q);
+	put_disk(disk);
 	return;
 out:
 	rcu_read_unlock();
-	blk_put_queue(q);
 }
 
 /**
@@ -1854,18 +1887,17 @@ out:
  */
 void blkcg_schedule_throttle(struct gendisk *disk, bool use_memdelay)
 {
-	struct request_queue *q = disk->queue;
-
 	if (unlikely(current->flags & PF_KTHREAD))
 		return;
 
-	if (current->throttle_queue != q) {
-		if (!blk_get_queue(q))
+	if (current->throttle_disk != disk) {
+		if (test_bit(GD_DEAD, &disk->state))
 			return;
+		get_device(disk_to_dev(disk));
 
-		if (current->throttle_queue)
-			blk_put_queue(current->throttle_queue);
-		current->throttle_queue = q;
+		if (current->throttle_disk)
+			put_disk(current->throttle_disk);
+		current->throttle_disk = disk;
 	}
 
 	if (use_memdelay)
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 1e94e404eaa8..9c5078755e5e 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -135,6 +135,7 @@ struct blkg_policy_data {
 	/* the blkg and policy id this per-policy data belongs to */
 	struct blkcg_gq			*blkg;
 	int				plid;
+	bool				online;
 };
 
 /*
@@ -154,8 +155,8 @@ typedef struct blkcg_policy_data *(blkcg_pol_alloc_cpd_fn)(gfp_t gfp);
 typedef void (blkcg_pol_init_cpd_fn)(struct blkcg_policy_data *cpd);
 typedef void (blkcg_pol_free_cpd_fn)(struct blkcg_policy_data *cpd);
 typedef void (blkcg_pol_bind_cpd_fn)(struct blkcg_policy_data *cpd);
-typedef struct blkg_policy_data *(blkcg_pol_alloc_pd_fn)(gfp_t gfp,
-				struct request_queue *q, struct blkcg *blkcg);
+typedef struct blkg_policy_data *(blkcg_pol_alloc_pd_fn)(struct gendisk *disk,
+		struct blkcg *blkcg, gfp_t gfp);
 typedef void (blkcg_pol_init_pd_fn)(struct blkg_policy_data *pd);
 typedef void (blkcg_pol_online_pd_fn)(struct blkg_policy_data *pd);
 typedef void (blkcg_pol_offline_pd_fn)(struct blkg_policy_data *pd);
@@ -194,9 +195,8 @@ void blkcg_exit_disk(struct gendisk *disk);
 /* Blkio controller policy registration */
 int blkcg_policy_register(struct blkcg_policy *pol);
 void blkcg_policy_unregister(struct blkcg_policy *pol);
-int blkcg_activate_policy(struct request_queue *q,
-			  const struct blkcg_policy *pol);
-void blkcg_deactivate_policy(struct request_queue *q,
+int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol);
+void blkcg_deactivate_policy(struct gendisk *disk,
 			     const struct blkcg_policy *pol);
 
 const char *blkg_dev_name(struct blkcg_gq *blkg);
@@ -495,9 +495,9 @@ static inline int blkcg_init_disk(struct gendisk *disk) { return 0; }
 static inline void blkcg_exit_disk(struct gendisk *disk) { }
 static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; }
 static inline void blkcg_policy_unregister(struct blkcg_policy *pol) { }
-static inline int blkcg_activate_policy(struct request_queue *q,
+static inline int blkcg_activate_policy(struct gendisk *disk,
 					const struct blkcg_policy *pol) { return 0; }
-static inline void blkcg_deactivate_policy(struct request_queue *q,
+static inline void blkcg_deactivate_policy(struct gendisk *disk,
 					   const struct blkcg_policy *pol) { }
 
 static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg,
diff --git a/block/blk-core.c b/block/blk-core.c
index b5098355d8b2..5fb6856745b4 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -570,7 +570,7 @@ static inline blk_status_t blk_check_zone_append(struct request_queue *q,
 		return BLK_STS_NOTSUPP;
 
 	/* The bio sector must point to the start of a sequential zone */
-	if (bio->bi_iter.bi_sector & (bdev_zone_sectors(bio->bi_bdev) - 1) ||
+	if (!bdev_is_zone_start(bio->bi_bdev, bio->bi_iter.bi_sector) ||
 	    !bio_zone_is_seq(bio))
 		return BLK_STS_IOERR;
 
@@ -684,6 +684,18 @@ static void __submit_bio_noacct_mq(struct bio *bio)
 
 void submit_bio_noacct_nocheck(struct bio *bio)
 {
+	blk_cgroup_bio_start(bio);
+	blkcg_bio_issue_init(bio);
+
+	if (!bio_flagged(bio, BIO_TRACE_COMPLETION)) {
+		trace_block_bio_queue(bio);
+		/*
+		 * Now that enqueuing has been traced, we need to trace
+		 * completion as well.
+		 */
+		bio_set_flag(bio, BIO_TRACE_COMPLETION);
+	}
+
 	/*
 	 * We only want one ->submit_bio to be active at a time, else stack
 	 * usage with stacked devices could be a problem.  Use current->bio_list
@@ -788,17 +800,6 @@ void submit_bio_noacct(struct bio *bio)
 
 	if (blk_throtl_bio(bio))
 		return;
-
-	blk_cgroup_bio_start(bio);
-	blkcg_bio_issue_init(bio);
-
-	if (!bio_flagged(bio, BIO_TRACE_COMPLETION)) {
-		trace_block_bio_queue(bio);
-		/* Now that enqueuing has been traced, we need to trace
-		 * completion as well.
-		 */
-		bio_set_flag(bio, BIO_TRACE_COMPLETION);
-	}
 	submit_bio_noacct_nocheck(bio);
 	return;
 
@@ -869,7 +870,16 @@ int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags)
 	 */
 	blk_flush_plug(current->plug, false);
 
-	if (bio_queue_enter(bio))
+	/*
+	 * We need to be able to enter a frozen queue, similar to how
+	 * timeouts also need to do that. If that is blocked, then we can
+	 * have pending IO when a queue freeze is started, and then the
+	 * wait for the freeze to finish will wait for polled requests to
+	 * timeout as the poller is preventer from entering the queue and
+	 * completing them. As long as we prevent new IO from being queued,
+	 * that should be all that matters.
+	 */
+	if (!percpu_ref_tryget(&q->q_usage_counter))
 		return 0;
 	if (queue_is_mq(q)) {
 		ret = blk_mq_poll(q, cookie, iob, flags);
diff --git a/block/blk-crypto-sysfs.c b/block/blk-crypto-sysfs.c
index 55268edc0625..a304434489ba 100644
--- a/block/blk-crypto-sysfs.c
+++ b/block/blk-crypto-sysfs.c
@@ -116,7 +116,7 @@ static void blk_crypto_release(struct kobject *kobj)
 	kfree(container_of(kobj, struct blk_crypto_kobj, kobj));
 }
 
-static struct kobj_type blk_crypto_ktype = {
+static const struct kobj_type blk_crypto_ktype = {
 	.default_groups = blk_crypto_attr_groups,
 	.sysfs_ops	= &blk_crypto_attr_ops,
 	.release	= blk_crypto_release,
diff --git a/block/blk-ia-ranges.c b/block/blk-ia-ranges.c
index 2141931ddd37..c9eb4241e048 100644
--- a/block/blk-ia-ranges.c
+++ b/block/blk-ia-ranges.c
@@ -75,7 +75,7 @@ static void blk_ia_range_sysfs_nop_release(struct kobject *kobj)
 {
 }
 
-static struct kobj_type blk_ia_range_ktype = {
+static const struct kobj_type blk_ia_range_ktype = {
 	.sysfs_ops	= &blk_ia_range_sysfs_ops,
 	.default_groups	= blk_ia_range_groups,
 	.release	= blk_ia_range_sysfs_nop_release,
@@ -94,7 +94,7 @@ static void blk_ia_ranges_sysfs_release(struct kobject *kobj)
 	kfree(iars);
 }
 
-static struct kobj_type blk_ia_ranges_ktype = {
+static const struct kobj_type blk_ia_ranges_ktype = {
 	.release	= blk_ia_ranges_sysfs_release,
 };
 
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 69eed260a823..8f01d786f5cb 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -356,7 +356,7 @@ static const struct sysfs_ops integrity_ops = {
 	.store	= &integrity_attr_store,
 };
 
-static struct kobj_type integrity_ktype = {
+static const struct kobj_type integrity_ktype = {
 	.default_groups = integrity_groups,
 	.sysfs_ops	= &integrity_ops,
 };
diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 6955605629e4..ff534e9d92dc 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -258,6 +258,11 @@ enum {
 	VRATE_MIN		= VTIME_PER_USEC * VRATE_MIN_PPM / MILLION,
 	VRATE_CLAMP_ADJ_PCT	= 4,
 
+	/* switch iff the conditions are met for longer than this */
+	AUTOP_CYCLE_NSEC	= 10LLU * NSEC_PER_SEC,
+};
+
+enum {
 	/* if IOs end up waiting for requests, issue less */
 	RQ_WAIT_BUSY_PCT	= 5,
 
@@ -296,9 +301,6 @@ enum {
 	/* don't let cmds which take a very long time pin lagging for too long */
 	MAX_LAGGING_PERIODS	= 10,
 
-	/* switch iff the conditions are met for longer than this */
-	AUTOP_CYCLE_NSEC	= 10LLU * NSEC_PER_SEC,
-
 	/*
 	 * Count IO size in 4k pages.  The 12bit shift helps keeping
 	 * size-proportional components of cost calculation in closer
@@ -667,7 +669,7 @@ static struct ioc *q_to_ioc(struct request_queue *q)
 
 static const char __maybe_unused *ioc_name(struct ioc *ioc)
 {
-	struct gendisk *disk = ioc->rqos.q->disk;
+	struct gendisk *disk = ioc->rqos.disk;
 
 	if (!disk)
 		return "<unknown>";
@@ -806,11 +808,11 @@ static int ioc_autop_idx(struct ioc *ioc)
 	u64 now_ns;
 
 	/* rotational? */
-	if (!blk_queue_nonrot(ioc->rqos.q))
+	if (!blk_queue_nonrot(ioc->rqos.disk->queue))
 		return AUTOP_HDD;
 
 	/* handle SATA SSDs w/ broken NCQ */
-	if (blk_queue_depth(ioc->rqos.q) == 1)
+	if (blk_queue_depth(ioc->rqos.disk->queue) == 1)
 		return AUTOP_SSD_QD1;
 
 	/* use one of the normal ssd sets */
@@ -866,9 +868,14 @@ static void calc_lcoefs(u64 bps, u64 seqiops, u64 randiops,
 
 	*page = *seqio = *randio = 0;
 
-	if (bps)
-		*page = DIV64_U64_ROUND_UP(VTIME_PER_SEC,
-					   DIV_ROUND_UP_ULL(bps, IOC_PAGE_SIZE));
+	if (bps) {
+		u64 bps_pages = DIV_ROUND_UP_ULL(bps, IOC_PAGE_SIZE);
+
+		if (bps_pages)
+			*page = DIV64_U64_ROUND_UP(VTIME_PER_SEC, bps_pages);
+		else
+			*page = 1;
+	}
 
 	if (seqiops) {
 		v = DIV64_U64_ROUND_UP(VTIME_PER_SEC, seqiops);
@@ -926,8 +933,8 @@ static bool ioc_refresh_params(struct ioc *ioc, bool force)
 
 	ioc->vrate_min = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MIN] *
 					    VTIME_PER_USEC, MILLION);
-	ioc->vrate_max = div64_u64((u64)ioc->params.qos[QOS_MAX] *
-				   VTIME_PER_USEC, MILLION);
+	ioc->vrate_max = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MAX] *
+					    VTIME_PER_USEC, MILLION);
 
 	return true;
 }
@@ -2642,7 +2649,7 @@ retry_lock:
 	if (use_debt) {
 		iocg_incur_debt(iocg, abs_cost, &now);
 		if (iocg_kick_delay(iocg, &now))
-			blkcg_schedule_throttle(rqos->q->disk,
+			blkcg_schedule_throttle(rqos->disk,
 					(bio->bi_opf & REQ_SWAP) == REQ_SWAP);
 		iocg_unlock(iocg, ioc_locked, &flags);
 		return;
@@ -2743,7 +2750,7 @@ static void ioc_rqos_merge(struct rq_qos *rqos, struct request *rq,
 	if (likely(!list_empty(&iocg->active_list))) {
 		iocg_incur_debt(iocg, abs_cost, &now);
 		if (iocg_kick_delay(iocg, &now))
-			blkcg_schedule_throttle(rqos->q->disk,
+			blkcg_schedule_throttle(rqos->disk,
 					(bio->bi_opf & REQ_SWAP) == REQ_SWAP);
 	} else {
 		iocg_commit_bio(iocg, bio, abs_cost, cost);
@@ -2814,7 +2821,7 @@ static void ioc_rqos_exit(struct rq_qos *rqos)
 {
 	struct ioc *ioc = rqos_to_ioc(rqos);
 
-	blkcg_deactivate_policy(rqos->q, &blkcg_policy_iocost);
+	blkcg_deactivate_policy(rqos->disk, &blkcg_policy_iocost);
 
 	spin_lock_irq(&ioc->lock);
 	ioc->running = IOC_STOP;
@@ -2825,7 +2832,7 @@ static void ioc_rqos_exit(struct rq_qos *rqos)
 	kfree(ioc);
 }
 
-static struct rq_qos_ops ioc_rqos_ops = {
+static const struct rq_qos_ops ioc_rqos_ops = {
 	.throttle = ioc_rqos_throttle,
 	.merge = ioc_rqos_merge,
 	.done_bio = ioc_rqos_done_bio,
@@ -2836,9 +2843,7 @@ static struct rq_qos_ops ioc_rqos_ops = {
 
 static int blk_iocost_init(struct gendisk *disk)
 {
-	struct request_queue *q = disk->queue;
 	struct ioc *ioc;
-	struct rq_qos *rqos;
 	int i, cpu, ret;
 
 	ioc = kzalloc(sizeof(*ioc), GFP_KERNEL);
@@ -2861,11 +2866,6 @@ static int blk_iocost_init(struct gendisk *disk)
 		local64_set(&ccs->rq_wait_ns, 0);
 	}
 
-	rqos = &ioc->rqos;
-	rqos->id = RQ_QOS_COST;
-	rqos->ops = &ioc_rqos_ops;
-	rqos->q = q;
-
 	spin_lock_init(&ioc->lock);
 	timer_setup(&ioc->timer, ioc_timer_fn, 0);
 	INIT_LIST_HEAD(&ioc->active_iocgs);
@@ -2889,17 +2889,17 @@ static int blk_iocost_init(struct gendisk *disk)
 	 * called before policy activation completion, can't assume that the
 	 * target bio has an iocg associated and need to test for NULL iocg.
 	 */
-	ret = rq_qos_add(q, rqos);
+	ret = rq_qos_add(&ioc->rqos, disk, RQ_QOS_COST, &ioc_rqos_ops);
 	if (ret)
 		goto err_free_ioc;
 
-	ret = blkcg_activate_policy(q, &blkcg_policy_iocost);
+	ret = blkcg_activate_policy(disk, &blkcg_policy_iocost);
 	if (ret)
 		goto err_del_qos;
 	return 0;
 
 err_del_qos:
-	rq_qos_del(q, rqos);
+	rq_qos_del(&ioc->rqos);
 err_free_ioc:
 	free_percpu(ioc->pcpu_stat);
 	kfree(ioc);
@@ -2923,13 +2923,14 @@ static void ioc_cpd_free(struct blkcg_policy_data *cpd)
 	kfree(container_of(cpd, struct ioc_cgrp, cpd));
 }
 
-static struct blkg_policy_data *ioc_pd_alloc(gfp_t gfp, struct request_queue *q,
-					     struct blkcg *blkcg)
+static struct blkg_policy_data *ioc_pd_alloc(struct gendisk *disk,
+		struct blkcg *blkcg, gfp_t gfp)
 {
 	int levels = blkcg->css.cgroup->level + 1;
 	struct ioc_gq *iocg;
 
-	iocg = kzalloc_node(struct_size(iocg, ancestors, levels), gfp, q->node);
+	iocg = kzalloc_node(struct_size(iocg, ancestors, levels), gfp,
+			    disk->node_id);
 	if (!iocg)
 		return NULL;
 
@@ -3129,6 +3130,7 @@ static u64 ioc_qos_prfill(struct seq_file *sf, struct blkg_policy_data *pd,
 	if (!dname)
 		return 0;
 
+	spin_lock_irq(&ioc->lock);
 	seq_printf(sf, "%s enable=%d ctrl=%s rpct=%u.%02u rlat=%u wpct=%u.%02u wlat=%u min=%u.%02u max=%u.%02u\n",
 		   dname, ioc->enabled, ioc->user_qos_params ? "user" : "auto",
 		   ioc->params.qos[QOS_RPPM] / 10000,
@@ -3141,6 +3143,7 @@ static u64 ioc_qos_prfill(struct seq_file *sf, struct blkg_policy_data *pd,
 		   ioc->params.qos[QOS_MIN] % 10000 / 100,
 		   ioc->params.qos[QOS_MAX] / 10000,
 		   ioc->params.qos[QOS_MAX] % 10000 / 100);
+	spin_unlock_irq(&ioc->lock);
 	return 0;
 }
 
@@ -3185,6 +3188,11 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
 		return PTR_ERR(bdev);
 
 	disk = bdev->bd_disk;
+	if (!queue_is_mq(disk->queue)) {
+		ret = -EOPNOTSUPP;
+		goto err;
+	}
+
 	ioc = q_to_ioc(disk->queue);
 	if (!ioc) {
 		ret = blk_iocost_init(disk);
@@ -3212,7 +3220,8 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
 
 		switch (match_token(p, qos_ctrl_tokens, args)) {
 		case QOS_ENABLE:
-			match_u64(&args[0], &v);
+			if (match_u64(&args[0], &v))
+				goto einval;
 			enable = v;
 			continue;
 		case QOS_CTRL:
@@ -3270,11 +3279,11 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
 		blk_stat_enable_accounting(disk->queue);
 		blk_queue_flag_set(QUEUE_FLAG_RQ_ALLOC_TIME, disk->queue);
 		ioc->enabled = true;
-		wbt_disable_default(disk->queue);
+		wbt_disable_default(disk);
 	} else {
 		blk_queue_flag_clear(QUEUE_FLAG_RQ_ALLOC_TIME, disk->queue);
 		ioc->enabled = false;
-		wbt_enable_default(disk->queue);
+		wbt_enable_default(disk);
 	}
 
 	if (user) {
@@ -3314,12 +3323,14 @@ static u64 ioc_cost_model_prfill(struct seq_file *sf,
 	if (!dname)
 		return 0;
 
+	spin_lock_irq(&ioc->lock);
 	seq_printf(sf, "%s ctrl=%s model=linear "
 		   "rbps=%llu rseqiops=%llu rrandiops=%llu "
 		   "wbps=%llu wseqiops=%llu wrandiops=%llu\n",
 		   dname, ioc->user_cost_model ? "user" : "auto",
 		   u[I_LCOEF_RBPS], u[I_LCOEF_RSEQIOPS], u[I_LCOEF_RRANDIOPS],
 		   u[I_LCOEF_WBPS], u[I_LCOEF_WSEQIOPS], u[I_LCOEF_WRANDIOPS]);
+	spin_unlock_irq(&ioc->lock);
 	return 0;
 }
 
@@ -3364,6 +3375,11 @@ static ssize_t ioc_cost_model_write(struct kernfs_open_file *of, char *input,
 		return PTR_ERR(bdev);
 
 	q = bdev_get_queue(bdev);
+	if (!queue_is_mq(q)) {
+		ret = -EOPNOTSUPP;
+		goto err;
+	}
+
 	ioc = q_to_ioc(q);
 	if (!ioc) {
 		ret = blk_iocost_init(bdev->bd_disk);
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
index ecdc10741836..0dc910568b31 100644
--- a/block/blk-iolatency.c
+++ b/block/blk-iolatency.c
@@ -292,7 +292,7 @@ static void __blkcg_iolatency_throttle(struct rq_qos *rqos,
 	unsigned use_delay = atomic_read(&lat_to_blkg(iolat)->use_delay);
 
 	if (use_delay)
-		blkcg_schedule_throttle(rqos->q->disk, use_memdelay);
+		blkcg_schedule_throttle(rqos->disk, use_memdelay);
 
 	/*
 	 * To avoid priority inversions we want to just take a slot if we are
@@ -330,7 +330,7 @@ static void scale_cookie_change(struct blk_iolatency *blkiolat,
 				struct child_latency_info *lat_info,
 				bool up)
 {
-	unsigned long qd = blkiolat->rqos.q->nr_requests;
+	unsigned long qd = blkiolat->rqos.disk->queue->nr_requests;
 	unsigned long scale = scale_amount(qd, up);
 	unsigned long old = atomic_read(&lat_info->scale_cookie);
 	unsigned long max_scale = qd << 1;
@@ -372,7 +372,7 @@ static void scale_cookie_change(struct blk_iolatency *blkiolat,
  */
 static void scale_change(struct iolatency_grp *iolat, bool up)
 {
-	unsigned long qd = iolat->blkiolat->rqos.q->nr_requests;
+	unsigned long qd = iolat->blkiolat->rqos.disk->queue->nr_requests;
 	unsigned long scale = scale_amount(qd, up);
 	unsigned long old = iolat->max_depth;
 
@@ -646,11 +646,11 @@ static void blkcg_iolatency_exit(struct rq_qos *rqos)
 
 	timer_shutdown_sync(&blkiolat->timer);
 	flush_work(&blkiolat->enable_work);
-	blkcg_deactivate_policy(rqos->q, &blkcg_policy_iolatency);
+	blkcg_deactivate_policy(rqos->disk, &blkcg_policy_iolatency);
 	kfree(blkiolat);
 }
 
-static struct rq_qos_ops blkcg_iolatency_ops = {
+static const struct rq_qos_ops blkcg_iolatency_ops = {
 	.throttle = blkcg_iolatency_throttle,
 	.done_bio = blkcg_iolatency_done_bio,
 	.exit = blkcg_iolatency_exit,
@@ -665,7 +665,7 @@ static void blkiolatency_timer_fn(struct timer_list *t)
 
 	rcu_read_lock();
 	blkg_for_each_descendant_pre(blkg, pos_css,
-				     blkiolat->rqos.q->root_blkg) {
+				     blkiolat->rqos.disk->queue->root_blkg) {
 		struct iolatency_grp *iolat;
 		struct child_latency_info *lat_info;
 		unsigned long flags;
@@ -749,32 +749,26 @@ static void blkiolatency_enable_work_fn(struct work_struct *work)
 	 */
 	enabled = atomic_read(&blkiolat->enable_cnt);
 	if (enabled != blkiolat->enabled) {
-		blk_mq_freeze_queue(blkiolat->rqos.q);
+		blk_mq_freeze_queue(blkiolat->rqos.disk->queue);
 		blkiolat->enabled = enabled;
-		blk_mq_unfreeze_queue(blkiolat->rqos.q);
+		blk_mq_unfreeze_queue(blkiolat->rqos.disk->queue);
 	}
 }
 
 int blk_iolatency_init(struct gendisk *disk)
 {
-	struct request_queue *q = disk->queue;
 	struct blk_iolatency *blkiolat;
-	struct rq_qos *rqos;
 	int ret;
 
 	blkiolat = kzalloc(sizeof(*blkiolat), GFP_KERNEL);
 	if (!blkiolat)
 		return -ENOMEM;
 
-	rqos = &blkiolat->rqos;
-	rqos->id = RQ_QOS_LATENCY;
-	rqos->ops = &blkcg_iolatency_ops;
-	rqos->q = q;
-
-	ret = rq_qos_add(q, rqos);
+	ret = rq_qos_add(&blkiolat->rqos, disk, RQ_QOS_LATENCY,
+			 &blkcg_iolatency_ops);
 	if (ret)
 		goto err_free;
-	ret = blkcg_activate_policy(q, &blkcg_policy_iolatency);
+	ret = blkcg_activate_policy(disk, &blkcg_policy_iolatency);
 	if (ret)
 		goto err_qos_del;
 
@@ -784,7 +778,7 @@ int blk_iolatency_init(struct gendisk *disk)
 	return 0;
 
 err_qos_del:
-	rq_qos_del(q, rqos);
+	rq_qos_del(&blkiolat->rqos);
 err_free:
 	kfree(blkiolat);
 	return ret;
@@ -952,13 +946,12 @@ static void iolatency_pd_stat(struct blkg_policy_data *pd, struct seq_file *s)
 			iolat->max_depth, avg_lat, cur_win);
 }
 
-static struct blkg_policy_data *iolatency_pd_alloc(gfp_t gfp,
-						   struct request_queue *q,
-						   struct blkcg *blkcg)
+static struct blkg_policy_data *iolatency_pd_alloc(struct gendisk *disk,
+		struct blkcg *blkcg, gfp_t gfp)
 {
 	struct iolatency_grp *iolat;
 
-	iolat = kzalloc_node(sizeof(*iolat), gfp, q->node);
+	iolat = kzalloc_node(sizeof(*iolat), gfp, disk->node_id);
 	if (!iolat)
 		return NULL;
 	iolat->stats = __alloc_percpu_gfp(sizeof(struct latency_stat),
diff --git a/block/blk-ioprio.c b/block/blk-ioprio.c
index 8bb6b8eba4ce..055529b9b92b 100644
--- a/block/blk-ioprio.c
+++ b/block/blk-ioprio.c
@@ -116,7 +116,7 @@ static ssize_t ioprio_set_prio_policy(struct kernfs_open_file *of, char *buf,
 }
 
 static struct blkg_policy_data *
-ioprio_alloc_pd(gfp_t gfp, struct request_queue *q, struct blkcg *blkcg)
+ioprio_alloc_pd(struct gendisk *disk, struct blkcg *blkcg, gfp_t gfp)
 {
 	struct ioprio_blkg *ioprio_blkg;
 
@@ -204,12 +204,12 @@ void blkcg_set_ioprio(struct bio *bio)
 
 void blk_ioprio_exit(struct gendisk *disk)
 {
-	blkcg_deactivate_policy(disk->queue, &ioprio_policy);
+	blkcg_deactivate_policy(disk, &ioprio_policy);
 }
 
 int blk_ioprio_init(struct gendisk *disk)
 {
-	return blkcg_activate_policy(disk->queue, &ioprio_policy);
+	return blkcg_activate_policy(disk, &ioprio_policy);
 }
 
 static int __init ioprio_init(void)
diff --git a/block/blk-map.c b/block/blk-map.c
index f2135e6ee8f6..9ee4be4ba2f1 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -247,10 +247,8 @@ static struct bio *blk_rq_map_bio_alloc(struct request *rq,
 {
 	struct bio *bio;
 
-	if (rq->cmd_flags & REQ_POLLED) {
-		blk_opf_t opf = rq->cmd_flags | REQ_ALLOC_CACHE;
-
-		bio = bio_alloc_bioset(NULL, nr_vecs, opf, gfp_mask,
+	if (rq->cmd_flags & REQ_ALLOC_CACHE) {
+		bio = bio_alloc_bioset(NULL, nr_vecs, rq->cmd_flags, gfp_mask,
 					&fs_bio_set);
 		if (!bio)
 			return NULL;
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 64bf7d9dd8e8..1ac782fdc55c 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -758,6 +758,33 @@ void blk_rq_set_mixed_merge(struct request *rq)
 	rq->rq_flags |= RQF_MIXED_MERGE;
 }
 
+static inline blk_opf_t bio_failfast(const struct bio *bio)
+{
+	if (bio->bi_opf & REQ_RAHEAD)
+		return REQ_FAILFAST_MASK;
+
+	return bio->bi_opf & REQ_FAILFAST_MASK;
+}
+
+/*
+ * After we are marked as MIXED_MERGE, any new RA bio has to be updated
+ * as failfast, and request's failfast has to be updated in case of
+ * front merge.
+ */
+static inline void blk_update_mixed_merge(struct request *req,
+		struct bio *bio, bool front_merge)
+{
+	if (req->rq_flags & RQF_MIXED_MERGE) {
+		if (bio->bi_opf & REQ_RAHEAD)
+			bio->bi_opf |= REQ_FAILFAST_MASK;
+
+		if (front_merge) {
+			req->cmd_flags &= ~REQ_FAILFAST_MASK;
+			req->cmd_flags |= bio->bi_opf & REQ_FAILFAST_MASK;
+		}
+	}
+}
+
 static void blk_account_io_merge_request(struct request *req)
 {
 	if (blk_do_io_stat(req)) {
@@ -955,7 +982,7 @@ enum bio_merge_status {
 static enum bio_merge_status bio_attempt_back_merge(struct request *req,
 		struct bio *bio, unsigned int nr_segs)
 {
-	const blk_opf_t ff = bio->bi_opf & REQ_FAILFAST_MASK;
+	const blk_opf_t ff = bio_failfast(bio);
 
 	if (!ll_back_merge_fn(req, bio, nr_segs))
 		return BIO_MERGE_FAILED;
@@ -966,6 +993,8 @@ static enum bio_merge_status bio_attempt_back_merge(struct request *req,
 	if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
 		blk_rq_set_mixed_merge(req);
 
+	blk_update_mixed_merge(req, bio, false);
+
 	req->biotail->bi_next = bio;
 	req->biotail = bio;
 	req->__data_len += bio->bi_iter.bi_size;
@@ -979,7 +1008,7 @@ static enum bio_merge_status bio_attempt_back_merge(struct request *req,
 static enum bio_merge_status bio_attempt_front_merge(struct request *req,
 		struct bio *bio, unsigned int nr_segs)
 {
-	const blk_opf_t ff = bio->bi_opf & REQ_FAILFAST_MASK;
+	const blk_opf_t ff = bio_failfast(bio);
 
 	if (!ll_front_merge_fn(req, bio, nr_segs))
 		return BIO_MERGE_FAILED;
@@ -990,6 +1019,8 @@ static enum bio_merge_status bio_attempt_front_merge(struct request *req,
 	if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
 		blk_rq_set_mixed_merge(req);
 
+	blk_update_mixed_merge(req, bio, true);
+
 	bio->bi_next = req->bio;
 	req->bio = bio;
 
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index bd942341b638..b01818f8e216 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -813,9 +813,9 @@ static const char *rq_qos_id_to_name(enum rq_qos_id id)
 
 void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos)
 {
-	lockdep_assert_held(&rqos->q->debugfs_mutex);
+	lockdep_assert_held(&rqos->disk->queue->debugfs_mutex);
 
-	if (!rqos->q->debugfs_dir)
+	if (!rqos->disk->queue->debugfs_dir)
 		return;
 	debugfs_remove_recursive(rqos->debugfs_dir);
 	rqos->debugfs_dir = NULL;
@@ -823,7 +823,7 @@ void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos)
 
 void blk_mq_debugfs_register_rqos(struct rq_qos *rqos)
 {
-	struct request_queue *q = rqos->q;
+	struct request_queue *q = rqos->disk->queue;
 	const char *dir_name = rq_qos_id_to_name(rqos->id);
 
 	lockdep_assert_held(&q->debugfs_mutex);
@@ -835,9 +835,7 @@ void blk_mq_debugfs_register_rqos(struct rq_qos *rqos)
 		q->rqos_debugfs_dir = debugfs_create_dir("rqos",
 							 q->debugfs_dir);
 
-	rqos->debugfs_dir = debugfs_create_dir(dir_name,
-					       rqos->q->rqos_debugfs_dir);
-
+	rqos->debugfs_dir = debugfs_create_dir(dir_name, q->rqos_debugfs_dir);
 	debugfs_create_files(rqos->debugfs_dir, rqos, rqos->ops->debugfs_attrs);
 }
 
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index 23d1a90fec42..06b312c69114 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -19,8 +19,7 @@
 #include "blk-wbt.h"
 
 /*
- * Mark a hardware queue as needing a restart. For shared queues, maintain
- * a count of how many hardware queues are marked for restart.
+ * Mark a hardware queue as needing a restart.
  */
 void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx)
 {
@@ -82,7 +81,7 @@ dispatch:
 /*
  * Only SCSI implements .get_budget and .put_budget, and SCSI restarts
  * its queue by itself in its completion handler, so we don't need to
- * restart queue if .get_budget() returns BLK_STS_NO_RESOURCE.
+ * restart queue if .get_budget() fails to get the budget.
  *
  * Returns -EAGAIN if hctx->dispatch was found non-empty and run_work has to
  * be run again.  This is necessary to avoid starving flushes.
@@ -210,7 +209,7 @@ static struct blk_mq_ctx *blk_mq_next_ctx(struct blk_mq_hw_ctx *hctx,
 /*
  * Only SCSI implements .get_budget and .put_budget, and SCSI restarts
  * its queue by itself in its completion handler, so we don't need to
- * restart queue if .get_budget() returns BLK_STS_NO_RESOURCE.
+ * restart queue if .get_budget() fails to get the budget.
  *
  * Returns -EAGAIN if hctx->dispatch was found non-empty and run_work has to
  * be run again.  This is necessary to avoid starving flushes.
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 4515288fbe35..1b2b0d258e46 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -46,7 +46,6 @@ static void blk_mq_hw_sysfs_release(struct kobject *kobj)
 struct blk_mq_hw_ctx_sysfs_entry {
 	struct attribute attr;
 	ssize_t (*show)(struct blk_mq_hw_ctx *, char *);
-	ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t);
 };
 
 static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
@@ -70,28 +69,6 @@ static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
 	return res;
 }
 
-static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj,
-				     struct attribute *attr, const char *page,
-				     size_t length)
-{
-	struct blk_mq_hw_ctx_sysfs_entry *entry;
-	struct blk_mq_hw_ctx *hctx;
-	struct request_queue *q;
-	ssize_t res;
-
-	entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
-	hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
-	q = hctx->queue;
-
-	if (!entry->store)
-		return -EIO;
-
-	mutex_lock(&q->sysfs_lock);
-	res = entry->store(hctx, page, length);
-	mutex_unlock(&q->sysfs_lock);
-	return res;
-}
-
 static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
 					    char *page)
 {
@@ -150,18 +127,17 @@ ATTRIBUTE_GROUPS(default_hw_ctx);
 
 static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
 	.show	= blk_mq_hw_sysfs_show,
-	.store	= blk_mq_hw_sysfs_store,
 };
 
-static struct kobj_type blk_mq_ktype = {
+static const struct kobj_type blk_mq_ktype = {
 	.release	= blk_mq_sysfs_release,
 };
 
-static struct kobj_type blk_mq_ctx_ktype = {
+static const struct kobj_type blk_mq_ctx_ktype = {
 	.release	= blk_mq_ctx_sysfs_release,
 };
 
-static struct kobj_type blk_mq_hw_ktype = {
+static const struct kobj_type blk_mq_hw_ktype = {
 	.sysfs_ops	= &blk_mq_hw_sysfs_ops,
 	.default_groups = default_hw_ctx_groups,
 	.release	= blk_mq_hw_sysfs_release,
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 9c8dc70020bc..d3494a796ba8 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -658,7 +658,8 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
 	 * allocator for this for the rare use case of a command tied to
 	 * a specific queue.
 	 */
-	if (WARN_ON_ONCE(!(flags & (BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED))))
+	if (WARN_ON_ONCE(!(flags & BLK_MQ_REQ_NOWAIT)) ||
+	    WARN_ON_ONCE(!(flags & BLK_MQ_REQ_RESERVED)))
 		return ERR_PTR(-EINVAL);
 
 	if (hctx_idx >= q->nr_hw_queues)
@@ -1825,12 +1826,13 @@ static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode,
 static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 				 struct request *rq)
 {
-	struct sbitmap_queue *sbq = &hctx->tags->bitmap_tags;
+	struct sbitmap_queue *sbq;
 	struct wait_queue_head *wq;
 	wait_queue_entry_t *wait;
 	bool ret;
 
-	if (!(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) {
+	if (!(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) &&
+	    !(blk_mq_is_shared_tags(hctx->flags))) {
 		blk_mq_sched_mark_restart_hctx(hctx);
 
 		/*
@@ -1848,6 +1850,10 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx *hctx,
 	if (!list_empty_careful(&wait->entry))
 		return false;
 
+	if (blk_mq_tag_is_reserved(rq->mq_hctx->sched_tags, rq->internal_tag))
+		sbq = &hctx->tags->breserved_tags;
+	else
+		sbq = &hctx->tags->bitmap_tags;
 	wq = &bt_wait_ptr(sbq, hctx)->wait;
 
 	spin_lock_irq(&wq->lock);
@@ -1917,16 +1923,6 @@ static void blk_mq_update_dispatch_busy(struct blk_mq_hw_ctx *hctx, bool busy)
 static void blk_mq_handle_dev_resource(struct request *rq,
 				       struct list_head *list)
 {
-	struct request *next =
-		list_first_entry_or_null(list, struct request, queuelist);
-
-	/*
-	 * If an I/O scheduler has been configured and we got a driver tag for
-	 * the next request already, free it.
-	 */
-	if (next)
-		blk_mq_put_driver_tag(next);
-
 	list_add(&rq->queuelist, list);
 	__blk_mq_requeue_request(rq);
 }
@@ -2002,6 +1998,23 @@ static void blk_mq_release_budgets(struct request_queue *q,
 }
 
 /*
+ * blk_mq_commit_rqs will notify driver using bd->last that there is no
+ * more requests. (See comment in struct blk_mq_ops for commit_rqs for
+ * details)
+ * Attention, we should explicitly call this in unusual cases:
+ *  1) did not queue everything initially scheduled to queue
+ *  2) the last attempt to queue a request failed
+ */
+static void blk_mq_commit_rqs(struct blk_mq_hw_ctx *hctx, int queued,
+			      bool from_schedule)
+{
+	if (hctx->queue->mq_ops->commit_rqs && queued) {
+		trace_block_unplug(hctx->queue, queued, !from_schedule);
+		hctx->queue->mq_ops->commit_rqs(hctx);
+	}
+}
+
+/*
  * Returns true if we did some work AND can potentially do more.
  */
 bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
@@ -2009,8 +2022,8 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
 {
 	enum prep_dispatch prep;
 	struct request_queue *q = hctx->queue;
-	struct request *rq, *nxt;
-	int errors, queued;
+	struct request *rq;
+	int queued;
 	blk_status_t ret = BLK_STS_OK;
 	LIST_HEAD(zone_list);
 	bool needs_resource = false;
@@ -2021,7 +2034,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
 	/*
 	 * Now process all the entries, sending them to the driver.
 	 */
-	errors = queued = 0;
+	queued = 0;
 	do {
 		struct blk_mq_queue_data bd;
 
@@ -2035,17 +2048,7 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
 		list_del_init(&rq->queuelist);
 
 		bd.rq = rq;
-
-		/*
-		 * Flag last if we have no more requests, or if we have more
-		 * but can't assign a driver tag to it.
-		 */
-		if (list_empty(list))
-			bd.last = true;
-		else {
-			nxt = list_first_entry(list, struct request, queuelist);
-			bd.last = !blk_mq_get_driver_tag(nxt);
-		}
+		bd.last = list_empty(list);
 
 		/*
 		 * once the request is queued to lld, no need to cover the
@@ -2074,7 +2077,6 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
 			needs_resource = true;
 			break;
 		default:
-			errors++;
 			blk_mq_end_request(rq, ret);
 		}
 	} while (!list_empty(list));
@@ -2085,9 +2087,9 @@ out:
 	/* If we didn't flush the entire list, we could have told the driver
 	 * there was more coming, but that turned out to be a lie.
 	 */
-	if ((!list_empty(list) || errors || needs_resource ||
-	     ret == BLK_STS_DEV_RESOURCE) && q->mq_ops->commit_rqs && queued)
-		q->mq_ops->commit_rqs(hctx);
+	if (!list_empty(list) || ret != BLK_STS_OK)
+		blk_mq_commit_rqs(hctx, queued, false);
+
 	/*
 	 * Any items that need requeuing? Stuff them into hctx->dispatch,
 	 * that is where we will continue on next queue run.
@@ -2096,7 +2098,8 @@ out:
 		bool needs_restart;
 		/* For non-shared tags, the RESTART check will suffice */
 		bool no_tag = prep == PREP_DISPATCH_NO_TAG &&
-			(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED);
+			((hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) ||
+			blk_mq_is_shared_tags(hctx->flags));
 
 		if (nr_budgets)
 			blk_mq_release_budgets(q, list);
@@ -2151,10 +2154,10 @@ out:
 
 		blk_mq_update_dispatch_busy(hctx, true);
 		return false;
-	} else
-		blk_mq_update_dispatch_busy(hctx, false);
+	}
 
-	return (queued + errors) != 0;
+	blk_mq_update_dispatch_busy(hctx, false);
+	return true;
 }
 
 /**
@@ -2548,16 +2551,6 @@ void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
 	spin_unlock(&ctx->lock);
 }
 
-static void blk_mq_commit_rqs(struct blk_mq_hw_ctx *hctx, int *queued,
-			      bool from_schedule)
-{
-	if (hctx->queue->mq_ops->commit_rqs) {
-		trace_block_unplug(hctx->queue, *queued, !from_schedule);
-		hctx->queue->mq_ops->commit_rqs(hctx);
-	}
-	*queued = 0;
-}
-
 static void blk_mq_bio_to_request(struct request *rq, struct bio *bio,
 		unsigned int nr_segs)
 {
@@ -2681,20 +2674,21 @@ static blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last)
 	return __blk_mq_try_issue_directly(rq->mq_hctx, rq, true, last);
 }
 
-static void blk_mq_plug_issue_direct(struct blk_plug *plug, bool from_schedule)
+static void blk_mq_plug_issue_direct(struct blk_plug *plug)
 {
 	struct blk_mq_hw_ctx *hctx = NULL;
 	struct request *rq;
 	int queued = 0;
-	int errors = 0;
+	blk_status_t ret = BLK_STS_OK;
 
 	while ((rq = rq_list_pop(&plug->mq_list))) {
 		bool last = rq_list_empty(plug->mq_list);
-		blk_status_t ret;
 
 		if (hctx != rq->mq_hctx) {
-			if (hctx)
-				blk_mq_commit_rqs(hctx, &queued, from_schedule);
+			if (hctx) {
+				blk_mq_commit_rqs(hctx, queued, false);
+				queued = 0;
+			}
 			hctx = rq->mq_hctx;
 		}
 
@@ -2706,21 +2700,16 @@ static void blk_mq_plug_issue_direct(struct blk_plug *plug, bool from_schedule)
 		case BLK_STS_RESOURCE:
 		case BLK_STS_DEV_RESOURCE:
 			blk_mq_request_bypass_insert(rq, false, true);
-			blk_mq_commit_rqs(hctx, &queued, from_schedule);
-			return;
+			goto out;
 		default:
 			blk_mq_end_request(rq, ret);
-			errors++;
 			break;
 		}
 	}
 
-	/*
-	 * If we didn't flush the entire list, we could have told the driver
-	 * there was more coming, but that turned out to be a lie.
-	 */
-	if (errors)
-		blk_mq_commit_rqs(hctx, &queued, from_schedule);
+out:
+	if (ret != BLK_STS_OK)
+		blk_mq_commit_rqs(hctx, queued, false);
 }
 
 static void __blk_mq_flush_plug_list(struct request_queue *q,
@@ -2791,7 +2780,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 		}
 
 		blk_mq_run_dispatch_ops(q,
-				blk_mq_plug_issue_direct(plug, false));
+				blk_mq_plug_issue_direct(plug));
 		if (rq_list_empty(plug->mq_list))
 			return;
 	}
@@ -2805,36 +2794,32 @@ void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
 		struct list_head *list)
 {
 	int queued = 0;
-	int errors = 0;
+	blk_status_t ret = BLK_STS_OK;
 
 	while (!list_empty(list)) {
-		blk_status_t ret;
 		struct request *rq = list_first_entry(list, struct request,
 				queuelist);
 
 		list_del_init(&rq->queuelist);
 		ret = blk_mq_request_issue_directly(rq, list_empty(list));
-		if (ret != BLK_STS_OK) {
-			errors++;
-			if (ret == BLK_STS_RESOURCE ||
-					ret == BLK_STS_DEV_RESOURCE) {
-				blk_mq_request_bypass_insert(rq, false,
-							list_empty(list));
-				break;
-			}
-			blk_mq_end_request(rq, ret);
-		} else
+		switch (ret) {
+		case BLK_STS_OK:
 			queued++;
+			break;
+		case BLK_STS_RESOURCE:
+		case BLK_STS_DEV_RESOURCE:
+			blk_mq_request_bypass_insert(rq, false,
+						     list_empty(list));
+			goto out;
+		default:
+			blk_mq_end_request(rq, ret);
+			break;
+		}
 	}
 
-	/*
-	 * If we didn't flush the entire list, we could have told
-	 * the driver there was more coming, but that turned out to
-	 * be a lie.
-	 */
-	if ((!list_empty(list) || errors) &&
-	     hctx->queue->mq_ops->commit_rqs && queued)
-		hctx->queue->mq_ops->commit_rqs(hctx);
+out:
+	if (ret != BLK_STS_OK)
+		blk_mq_commit_rqs(hctx, queued, false);
 }
 
 static bool blk_mq_attempt_bio_merge(struct request_queue *q,
@@ -2894,15 +2879,16 @@ static inline struct request *blk_mq_get_cached_request(struct request_queue *q,
 
 	if (!plug)
 		return NULL;
-	rq = rq_list_peek(&plug->cached_rq);
-	if (!rq || rq->q != q)
-		return NULL;
 
 	if (blk_mq_attempt_bio_merge(q, *bio, nsegs)) {
 		*bio = NULL;
 		return NULL;
 	}
 
+	rq = rq_list_peek(&plug->cached_rq);
+	if (!rq || rq->q != q)
+		return NULL;
+
 	type = blk_mq_get_hctx_type((*bio)->bi_opf);
 	hctx_type = rq->mq_hctx->type;
 	if (type != hctx_type &&
diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c
index 88f0fe7dcf54..d8cc820a365e 100644
--- a/block/blk-rq-qos.c
+++ b/block/blk-rq-qos.c
@@ -294,3 +294,70 @@ void rq_qos_exit(struct request_queue *q)
 		rqos->ops->exit(rqos);
 	}
 }
+
+int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id,
+		const struct rq_qos_ops *ops)
+{
+	struct request_queue *q = disk->queue;
+
+	rqos->disk = disk;
+	rqos->id = id;
+	rqos->ops = ops;
+
+	/*
+	 * No IO can be in-flight when adding rqos, so freeze queue, which
+	 * is fine since we only support rq_qos for blk-mq queue.
+	 *
+	 * Reuse ->queue_lock for protecting against other concurrent
+	 * rq_qos adding/deleting
+	 */
+	blk_mq_freeze_queue(q);
+
+	spin_lock_irq(&q->queue_lock);
+	if (rq_qos_id(q, rqos->id))
+		goto ebusy;
+	rqos->next = q->rq_qos;
+	q->rq_qos = rqos;
+	spin_unlock_irq(&q->queue_lock);
+
+	blk_mq_unfreeze_queue(q);
+
+	if (rqos->ops->debugfs_attrs) {
+		mutex_lock(&q->debugfs_mutex);
+		blk_mq_debugfs_register_rqos(rqos);
+		mutex_unlock(&q->debugfs_mutex);
+	}
+
+	return 0;
+ebusy:
+	spin_unlock_irq(&q->queue_lock);
+	blk_mq_unfreeze_queue(q);
+	return -EBUSY;
+}
+
+void rq_qos_del(struct rq_qos *rqos)
+{
+	struct request_queue *q = rqos->disk->queue;
+	struct rq_qos **cur;
+
+	/*
+	 * See comment in rq_qos_add() about freezing queue & using
+	 * ->queue_lock.
+	 */
+	blk_mq_freeze_queue(q);
+
+	spin_lock_irq(&q->queue_lock);
+	for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) {
+		if (*cur == rqos) {
+			*cur = rqos->next;
+			break;
+		}
+	}
+	spin_unlock_irq(&q->queue_lock);
+
+	blk_mq_unfreeze_queue(q);
+
+	mutex_lock(&q->debugfs_mutex);
+	blk_mq_debugfs_unregister_rqos(rqos);
+	mutex_unlock(&q->debugfs_mutex);
+}
diff --git a/block/blk-rq-qos.h b/block/blk-rq-qos.h
index 1ef1f7d4bc3c..b02a1a3d33a8 100644
--- a/block/blk-rq-qos.h
+++ b/block/blk-rq-qos.h
@@ -25,8 +25,8 @@ struct rq_wait {
 };
 
 struct rq_qos {
-	struct rq_qos_ops *ops;
-	struct request_queue *q;
+	const struct rq_qos_ops *ops;
+	struct gendisk *disk;
 	enum rq_qos_id id;
 	struct rq_qos *next;
 #ifdef CONFIG_BLK_DEBUG_FS
@@ -85,65 +85,9 @@ static inline void rq_wait_init(struct rq_wait *rq_wait)
 	init_waitqueue_head(&rq_wait->wait);
 }
 
-static inline int rq_qos_add(struct request_queue *q, struct rq_qos *rqos)
-{
-	/*
-	 * No IO can be in-flight when adding rqos, so freeze queue, which
-	 * is fine since we only support rq_qos for blk-mq queue.
-	 *
-	 * Reuse ->queue_lock for protecting against other concurrent
-	 * rq_qos adding/deleting
-	 */
-	blk_mq_freeze_queue(q);
-
-	spin_lock_irq(&q->queue_lock);
-	if (rq_qos_id(q, rqos->id))
-		goto ebusy;
-	rqos->next = q->rq_qos;
-	q->rq_qos = rqos;
-	spin_unlock_irq(&q->queue_lock);
-
-	blk_mq_unfreeze_queue(q);
-
-	if (rqos->ops->debugfs_attrs) {
-		mutex_lock(&q->debugfs_mutex);
-		blk_mq_debugfs_register_rqos(rqos);
-		mutex_unlock(&q->debugfs_mutex);
-	}
-
-	return 0;
-ebusy:
-	spin_unlock_irq(&q->queue_lock);
-	blk_mq_unfreeze_queue(q);
-	return -EBUSY;
-
-}
-
-static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos)
-{
-	struct rq_qos **cur;
-
-	/*
-	 * See comment in rq_qos_add() about freezing queue & using
-	 * ->queue_lock.
-	 */
-	blk_mq_freeze_queue(q);
-
-	spin_lock_irq(&q->queue_lock);
-	for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) {
-		if (*cur == rqos) {
-			*cur = rqos->next;
-			break;
-		}
-	}
-	spin_unlock_irq(&q->queue_lock);
-
-	blk_mq_unfreeze_queue(q);
-
-	mutex_lock(&q->debugfs_mutex);
-	blk_mq_debugfs_unregister_rqos(rqos);
-	mutex_unlock(&q->debugfs_mutex);
-}
+int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id,
+		const struct rq_qos_ops *ops);
+void rq_qos_del(struct rq_qos *rqos);
 
 typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data);
 typedef void (cleanup_cb_t)(struct rq_wait *rqw, void *private_data);
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 0477c4d527fe..896b4654ab00 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -16,6 +16,7 @@
 #include <linux/dma-mapping.h>
 
 #include "blk.h"
+#include "blk-rq-qos.h"
 #include "blk-wbt.h"
 
 void blk_queue_rq_timeout(struct request_queue *q, unsigned int timeout)
@@ -40,7 +41,7 @@ void blk_set_default_limits(struct queue_limits *lim)
 	lim->virt_boundary_mask = 0;
 	lim->max_segment_size = BLK_MAX_SEGMENT_SIZE;
 	lim->max_sectors = lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS;
-	lim->max_dev_sectors = 0;
+	lim->max_user_sectors = lim->max_dev_sectors = 0;
 	lim->chunk_sectors = 0;
 	lim->max_write_zeroes_sectors = 0;
 	lim->max_zone_append_sectors = 0;
@@ -135,7 +136,12 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto
 	limits->max_hw_sectors = max_hw_sectors;
 
 	max_sectors = min_not_zero(max_hw_sectors, limits->max_dev_sectors);
-	max_sectors = min_t(unsigned int, max_sectors, BLK_DEF_MAX_SECTORS);
+
+	if (limits->max_user_sectors)
+		max_sectors = min(max_sectors, limits->max_user_sectors);
+	else
+		max_sectors = min(max_sectors, BLK_DEF_MAX_SECTORS);
+
 	max_sectors = round_down(max_sectors,
 				 limits->logical_block_size >> SECTOR_SHIFT);
 	limits->max_sectors = max_sectors;
diff --git a/block/blk-stat.c b/block/blk-stat.c
index 2ea01b5c1aca..c6ca16abf911 100644
--- a/block/blk-stat.c
+++ b/block/blk-stat.c
@@ -58,7 +58,8 @@ void blk_stat_add(struct request *rq, u64 now)
 
 	value = (now >= rq->io_start_time_ns) ? now - rq->io_start_time_ns : 0;
 
-	blk_throtl_stat_add(rq, value);
+	if (req_op(rq) == REQ_OP_READ || req_op(rq) == REQ_OP_WRITE)
+		blk_throtl_stat_add(rq, value);
 
 	rcu_read_lock();
 	cpu = get_cpu();
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 93d9e9c9a6ea..f1fce1c7fa44 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -16,6 +16,7 @@
 #include "blk-mq.h"
 #include "blk-mq-debugfs.h"
 #include "blk-mq-sched.h"
+#include "blk-rq-qos.h"
 #include "blk-wbt.h"
 #include "blk-cgroup.h"
 #include "blk-throttle.h"
@@ -239,19 +240,28 @@ static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page)
 static ssize_t
 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
 {
-	unsigned long max_sectors_kb,
+	unsigned long var;
+	unsigned int max_sectors_kb,
 		max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
 			page_kb = 1 << (PAGE_SHIFT - 10);
-	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
+	ssize_t ret = queue_var_store(&var, page, count);
 
 	if (ret < 0)
 		return ret;
 
-	max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, (unsigned long)
+	max_sectors_kb = (unsigned int)var;
+	max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb,
 					 q->limits.max_dev_sectors >> 1);
-
-	if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
-		return -EINVAL;
+	if (max_sectors_kb == 0) {
+		q->limits.max_user_sectors = 0;
+		max_sectors_kb = min(max_hw_sectors_kb,
+				     BLK_DEF_MAX_SECTORS >> 1);
+	} else {
+		if (max_sectors_kb > max_hw_sectors_kb ||
+		    max_sectors_kb < page_kb)
+			return -EINVAL;
+		q->limits.max_user_sectors = max_sectors_kb << 1;
+	}
 
 	spin_lock_irq(&q->queue_lock);
 	q->limits.max_sectors = max_sectors_kb << 1;
@@ -491,7 +501,7 @@ static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
 
 	rqos = wbt_rq_qos(q);
 	if (!rqos) {
-		ret = wbt_init(q);
+		ret = wbt_init(q->disk);
 		if (ret)
 			return ret;
 	}
@@ -755,7 +765,7 @@ static void blk_queue_release(struct kobject *kobj)
 	/* nothing to do here, all data is associated with the parent gendisk */
 }
 
-static struct kobj_type blk_queue_ktype = {
+static const struct kobj_type blk_queue_ktype = {
 	.default_groups = blk_queue_attr_groups,
 	.sysfs_ops	= &queue_sysfs_ops,
 	.release	= blk_queue_release,
@@ -817,7 +827,7 @@ int blk_register_queue(struct gendisk *disk)
 		goto out_elv_unregister;
 
 	blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q);
-	wbt_enable_default(q);
+	wbt_enable_default(disk);
 	blk_throtl_register(disk);
 
 	/* Now everything is ready and send out KOBJ_ADD uevent */
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 6fb5a2f9e1ee..47e9d8be68f3 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -335,14 +335,13 @@ static void throtl_service_queue_init(struct throtl_service_queue *sq)
 	timer_setup(&sq->pending_timer, throtl_pending_timer_fn, 0);
 }
 
-static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp,
-						struct request_queue *q,
-						struct blkcg *blkcg)
+static struct blkg_policy_data *throtl_pd_alloc(struct gendisk *disk,
+		struct blkcg *blkcg, gfp_t gfp)
 {
 	struct throtl_grp *tg;
 	int rw;
 
-	tg = kzalloc_node(sizeof(*tg), gfp, q->node);
+	tg = kzalloc_node(sizeof(*tg), gfp, disk->node_id);
 	if (!tg)
 		return NULL;
 
@@ -2395,7 +2394,7 @@ int blk_throtl_init(struct gendisk *disk)
 	td->low_downgrade_time = jiffies;
 
 	/* activate policy */
-	ret = blkcg_activate_policy(q, &blkcg_policy_throtl);
+	ret = blkcg_activate_policy(disk, &blkcg_policy_throtl);
 	if (ret) {
 		free_percpu(td->latency_buckets[READ]);
 		free_percpu(td->latency_buckets[WRITE]);
@@ -2411,7 +2410,7 @@ void blk_throtl_exit(struct gendisk *disk)
 	BUG_ON(!q->td);
 	del_timer_sync(&q->td->service_queue.pending_timer);
 	throtl_shutdown_wq(q);
-	blkcg_deactivate_policy(q, &blkcg_policy_throtl);
+	blkcg_deactivate_policy(disk, &blkcg_policy_throtl);
 	free_percpu(q->td->latency_buckets[READ]);
 	free_percpu(q->td->latency_buckets[WRITE]);
 	kfree(q->td);
diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index 68a774d7a7c9..e49a48684532 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -25,6 +25,7 @@
 #include <linux/backing-dev.h>
 #include <linux/swap.h>
 
+#include "blk-stat.h"
 #include "blk-wbt.h"
 #include "blk-rq-qos.h"
 #include "elevator.h"
@@ -32,6 +33,72 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/wbt.h>
 
+enum wbt_flags {
+	WBT_TRACKED		= 1,	/* write, tracked for throttling */
+	WBT_READ		= 2,	/* read */
+	WBT_KSWAPD		= 4,	/* write, from kswapd */
+	WBT_DISCARD		= 8,	/* discard */
+
+	WBT_NR_BITS		= 4,	/* number of bits */
+};
+
+enum {
+	WBT_RWQ_BG		= 0,
+	WBT_RWQ_KSWAPD,
+	WBT_RWQ_DISCARD,
+	WBT_NUM_RWQ,
+};
+
+/*
+ * If current state is WBT_STATE_ON/OFF_DEFAULT, it can be covered to any other
+ * state, if current state is WBT_STATE_ON/OFF_MANUAL, it can only be covered
+ * to WBT_STATE_OFF/ON_MANUAL.
+ */
+enum {
+	WBT_STATE_ON_DEFAULT	= 1,	/* on by default */
+	WBT_STATE_ON_MANUAL	= 2,	/* on manually by sysfs */
+	WBT_STATE_OFF_DEFAULT	= 3,	/* off by default */
+	WBT_STATE_OFF_MANUAL	= 4,	/* off manually by sysfs */
+};
+
+struct rq_wb {
+	/*
+	 * Settings that govern how we throttle
+	 */
+	unsigned int wb_background;		/* background writeback */
+	unsigned int wb_normal;			/* normal writeback */
+
+	short enable_state;			/* WBT_STATE_* */
+
+	/*
+	 * Number of consecutive periods where we don't have enough
+	 * information to make a firm scale up/down decision.
+	 */
+	unsigned int unknown_cnt;
+
+	u64 win_nsec;				/* default window size */
+	u64 cur_win_nsec;			/* current window size */
+
+	struct blk_stat_callback *cb;
+
+	u64 sync_issue;
+	void *sync_cookie;
+
+	unsigned int wc;
+
+	unsigned long last_issue;		/* last non-throttled issue */
+	unsigned long last_comp;		/* last non-throttled comp */
+	unsigned long min_lat_nsec;
+	struct rq_qos rqos;
+	struct rq_wait rq_wait[WBT_NUM_RWQ];
+	struct rq_depth rq_depth;
+};
+
+static inline struct rq_wb *RQWB(struct rq_qos *rqos)
+{
+	return container_of(rqos, struct rq_wb, rqos);
+}
+
 static inline void wbt_clear_state(struct request *rq)
 {
 	rq->wbt_flags = 0;
@@ -98,7 +165,7 @@ static void wb_timestamp(struct rq_wb *rwb, unsigned long *var)
  */
 static bool wb_recent_wait(struct rq_wb *rwb)
 {
-	struct bdi_writeback *wb = &rwb->rqos.q->disk->bdi->wb;
+	struct bdi_writeback *wb = &rwb->rqos.disk->bdi->wb;
 
 	return time_before(jiffies, wb->dirty_sleep + HZ);
 }
@@ -226,6 +293,16 @@ static u64 rwb_sync_issue_lat(struct rq_wb *rwb)
 	return now - issue;
 }
 
+static inline unsigned int wbt_inflight(struct rq_wb *rwb)
+{
+	unsigned int i, ret = 0;
+
+	for (i = 0; i < WBT_NUM_RWQ; i++)
+		ret += atomic_read(&rwb->rq_wait[i].inflight);
+
+	return ret;
+}
+
 enum {
 	LAT_OK = 1,
 	LAT_UNKNOWN,
@@ -235,7 +312,7 @@ enum {
 
 static int latency_exceeded(struct rq_wb *rwb, struct blk_rq_stat *stat)
 {
-	struct backing_dev_info *bdi = rwb->rqos.q->disk->bdi;
+	struct backing_dev_info *bdi = rwb->rqos.disk->bdi;
 	struct rq_depth *rqd = &rwb->rq_depth;
 	u64 thislat;
 
@@ -288,7 +365,7 @@ static int latency_exceeded(struct rq_wb *rwb, struct blk_rq_stat *stat)
 
 static void rwb_trace_step(struct rq_wb *rwb, const char *msg)
 {
-	struct backing_dev_info *bdi = rwb->rqos.q->disk->bdi;
+	struct backing_dev_info *bdi = rwb->rqos.disk->bdi;
 	struct rq_depth *rqd = &rwb->rq_depth;
 
 	trace_wbt_step(bdi, msg, rqd->scale_step, rwb->cur_win_nsec,
@@ -358,13 +435,12 @@ static void wb_timer_fn(struct blk_stat_callback *cb)
 	unsigned int inflight = wbt_inflight(rwb);
 	int status;
 
-	if (!rwb->rqos.q->disk)
+	if (!rwb->rqos.disk)
 		return;
 
 	status = latency_exceeded(rwb, cb->stat);
 
-	trace_wbt_timer(rwb->rqos.q->disk->bdi, status, rqd->scale_step,
-			inflight);
+	trace_wbt_timer(rwb->rqos.disk->bdi, status, rqd->scale_step, inflight);
 
 	/*
 	 * If we exceeded the latency target, step down. If we did not,
@@ -650,8 +726,9 @@ void wbt_set_write_cache(struct request_queue *q, bool write_cache_on)
 /*
  * Enable wbt if defaults are configured that way
  */
-void wbt_enable_default(struct request_queue *q)
+void wbt_enable_default(struct gendisk *disk)
 {
+	struct request_queue *q = disk->queue;
 	struct rq_qos *rqos;
 	bool disable_flag = q->elevator &&
 		    test_bit(ELEVATOR_FLAG_DISABLE_WBT, &q->elevator->flags);
@@ -670,7 +747,7 @@ void wbt_enable_default(struct request_queue *q)
 		return;
 
 	if (queue_is_mq(q) && !disable_flag)
-		wbt_init(q);
+		wbt_init(disk);
 }
 EXPORT_SYMBOL_GPL(wbt_enable_default);
 
@@ -701,16 +778,15 @@ static int wbt_data_dir(const struct request *rq)
 
 static void wbt_queue_depth_changed(struct rq_qos *rqos)
 {
-	RQWB(rqos)->rq_depth.queue_depth = blk_queue_depth(rqos->q);
+	RQWB(rqos)->rq_depth.queue_depth = blk_queue_depth(rqos->disk->queue);
 	wbt_update_limits(RQWB(rqos));
 }
 
 static void wbt_exit(struct rq_qos *rqos)
 {
 	struct rq_wb *rwb = RQWB(rqos);
-	struct request_queue *q = rqos->q;
 
-	blk_stat_remove_callback(q, rwb->cb);
+	blk_stat_remove_callback(rqos->disk->queue, rwb->cb);
 	blk_stat_free_callback(rwb->cb);
 	kfree(rwb);
 }
@@ -718,9 +794,9 @@ static void wbt_exit(struct rq_qos *rqos)
 /*
  * Disable wbt, if enabled by default.
  */
-void wbt_disable_default(struct request_queue *q)
+void wbt_disable_default(struct gendisk *disk)
 {
-	struct rq_qos *rqos = wbt_rq_qos(q);
+	struct rq_qos *rqos = wbt_rq_qos(disk->queue);
 	struct rq_wb *rwb;
 	if (!rqos)
 		return;
@@ -820,7 +896,7 @@ static const struct blk_mq_debugfs_attr wbt_debugfs_attrs[] = {
 };
 #endif
 
-static struct rq_qos_ops wbt_rqos_ops = {
+static const struct rq_qos_ops wbt_rqos_ops = {
 	.throttle = wbt_wait,
 	.issue = wbt_issue,
 	.track = wbt_track,
@@ -834,8 +910,9 @@ static struct rq_qos_ops wbt_rqos_ops = {
 #endif
 };
 
-int wbt_init(struct request_queue *q)
+int wbt_init(struct gendisk *disk)
 {
+	struct request_queue *q = disk->queue;
 	struct rq_wb *rwb;
 	int i;
 	int ret;
@@ -853,22 +930,19 @@ int wbt_init(struct request_queue *q)
 	for (i = 0; i < WBT_NUM_RWQ; i++)
 		rq_wait_init(&rwb->rq_wait[i]);
 
-	rwb->rqos.id = RQ_QOS_WBT;
-	rwb->rqos.ops = &wbt_rqos_ops;
-	rwb->rqos.q = q;
 	rwb->last_comp = rwb->last_issue = jiffies;
 	rwb->win_nsec = RWB_WINDOW_NSEC;
 	rwb->enable_state = WBT_STATE_ON_DEFAULT;
 	rwb->wc = test_bit(QUEUE_FLAG_WC, &q->queue_flags);
 	rwb->rq_depth.default_depth = RWB_DEF_DEPTH;
 	rwb->min_lat_nsec = wbt_default_latency_nsec(q);
-
-	wbt_queue_depth_changed(&rwb->rqos);
+	rwb->rq_depth.queue_depth = blk_queue_depth(q);
+	wbt_update_limits(rwb);
 
 	/*
 	 * Assign rwb and add the stats callback.
 	 */
-	ret = rq_qos_add(q, &rwb->rqos);
+	ret = rq_qos_add(&rwb->rqos, disk, RQ_QOS_WBT, &wbt_rqos_ops);
 	if (ret)
 		goto err_free;
 
diff --git a/block/blk-wbt.h b/block/blk-wbt.h
index e3ea6e7e2900..ba6cca5849a6 100644
--- a/block/blk-wbt.h
+++ b/block/blk-wbt.h
@@ -2,97 +2,11 @@
 #ifndef WB_THROTTLE_H
 #define WB_THROTTLE_H
 
-#include <linux/kernel.h>
-#include <linux/atomic.h>
-#include <linux/wait.h>
-#include <linux/timer.h>
-#include <linux/ktime.h>
-
-#include "blk-stat.h"
-#include "blk-rq-qos.h"
-
-enum wbt_flags {
-	WBT_TRACKED		= 1,	/* write, tracked for throttling */
-	WBT_READ		= 2,	/* read */
-	WBT_KSWAPD		= 4,	/* write, from kswapd */
-	WBT_DISCARD		= 8,	/* discard */
-
-	WBT_NR_BITS		= 4,	/* number of bits */
-};
-
-enum {
-	WBT_RWQ_BG		= 0,
-	WBT_RWQ_KSWAPD,
-	WBT_RWQ_DISCARD,
-	WBT_NUM_RWQ,
-};
-
-/*
- * If current state is WBT_STATE_ON/OFF_DEFAULT, it can be covered to any other
- * state, if current state is WBT_STATE_ON/OFF_MANUAL, it can only be covered
- * to WBT_STATE_OFF/ON_MANUAL.
- */
-enum {
-	WBT_STATE_ON_DEFAULT	= 1,	/* on by default */
-	WBT_STATE_ON_MANUAL	= 2,	/* on manually by sysfs */
-	WBT_STATE_OFF_DEFAULT	= 3,	/* off by default */
-	WBT_STATE_OFF_MANUAL	= 4,	/* off manually by sysfs */
-};
-
-struct rq_wb {
-	/*
-	 * Settings that govern how we throttle
-	 */
-	unsigned int wb_background;		/* background writeback */
-	unsigned int wb_normal;			/* normal writeback */
-
-	short enable_state;			/* WBT_STATE_* */
-
-	/*
-	 * Number of consecutive periods where we don't have enough
-	 * information to make a firm scale up/down decision.
-	 */
-	unsigned int unknown_cnt;
-
-	u64 win_nsec;				/* default window size */
-	u64 cur_win_nsec;			/* current window size */
-
-	struct blk_stat_callback *cb;
-
-	u64 sync_issue;
-	void *sync_cookie;
-
-	unsigned int wc;
-
-	unsigned long last_issue;		/* last non-throttled issue */
-	unsigned long last_comp;		/* last non-throttled comp */
-	unsigned long min_lat_nsec;
-	struct rq_qos rqos;
-	struct rq_wait rq_wait[WBT_NUM_RWQ];
-	struct rq_depth rq_depth;
-};
-
-static inline struct rq_wb *RQWB(struct rq_qos *rqos)
-{
-	return container_of(rqos, struct rq_wb, rqos);
-}
-
-static inline unsigned int wbt_inflight(struct rq_wb *rwb)
-{
-	unsigned int i, ret = 0;
-
-	for (i = 0; i < WBT_NUM_RWQ; i++)
-		ret += atomic_read(&rwb->rq_wait[i].inflight);
-
-	return ret;
-}
-
-
 #ifdef CONFIG_BLK_WBT
 
-int wbt_init(struct request_queue *);
-void wbt_disable_default(struct request_queue *);
-void wbt_enable_default(struct request_queue *);
+int wbt_init(struct gendisk *disk);
+void wbt_disable_default(struct gendisk *disk);
+void wbt_enable_default(struct gendisk *disk);
 
 u64 wbt_get_min_lat(struct request_queue *q);
 void wbt_set_min_lat(struct request_queue *q, u64 val);
@@ -104,14 +18,14 @@ u64 wbt_default_latency_nsec(struct request_queue *);
 
 #else
 
-static inline int wbt_init(struct request_queue *q)
+static inline int wbt_init(struct gendisk *disk)
 {
 	return -EINVAL;
 }
-static inline void wbt_disable_default(struct request_queue *q)
+static inline void wbt_disable_default(struct gendisk *disk)
 {
 }
-static inline void wbt_enable_default(struct request_queue *q)
+static inline void wbt_enable_default(struct gendisk *disk)
 {
 }
 static inline void wbt_set_write_cache(struct request_queue *q, bool wc)
diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index db829401d8d0..614b575be899 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -277,10 +277,10 @@ int blkdev_zone_mgmt(struct block_device *bdev, enum req_op op,
 		return -EINVAL;
 
 	/* Check alignment (handle eventual smaller last zone) */
-	if (sector & (zone_sectors - 1))
+	if (!bdev_is_zone_start(bdev, sector))
 		return -EINVAL;
 
-	if ((nr_sectors & (zone_sectors - 1)) && end_sector != capacity)
+	if (!bdev_is_zone_start(bdev, nr_sectors) && end_sector != capacity)
 		return -EINVAL;
 
 	/*
diff --git a/block/elevator.c b/block/elevator.c
index adee58e48e2d..24909069f872 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -126,7 +126,7 @@ static struct elevator_type *elevator_find_get(struct request_queue *q,
 	return e;
 }
 
-static struct kobj_type elv_ktype;
+static const struct kobj_type elv_ktype;
 
 struct elevator_queue *elevator_alloc(struct request_queue *q,
 				  struct elevator_type *e)
@@ -455,7 +455,7 @@ static const struct sysfs_ops elv_sysfs_ops = {
 	.store	= elv_attr_store,
 };
 
-static struct kobj_type elv_ktype = {
+static const struct kobj_type elv_ktype = {
 	.sysfs_ops	= &elv_sysfs_ops,
 	.release	= elevator_release,
 };
diff --git a/block/fops.c b/block/fops.c
index 50d245e8c913..d2e6be4e3d1c 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -221,6 +221,24 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 			bio_endio(bio);
 			break;
 		}
+		if (iocb->ki_flags & IOCB_NOWAIT) {
+			/*
+			 * This is nonblocking IO, and we need to allocate
+			 * another bio if we have data left to map. As we
+			 * cannot guarantee that one of the sub bios will not
+			 * fail getting issued FOR NOWAIT and as error results
+			 * are coalesced across all of them, be safe and ask for
+			 * a retry of this from blocking context.
+			 */
+			if (unlikely(iov_iter_count(iter))) {
+				bio_release_pages(bio, false);
+				bio_clear_flag(bio, BIO_REFFED);
+				bio_put(bio);
+				blk_finish_plug(&plug);
+				return -EAGAIN;
+			}
+			bio->bi_opf |= REQ_NOWAIT;
+		}
 
 		if (is_read) {
 			if (dio->flags & DIO_SHOULD_DIRTY)
@@ -228,9 +246,6 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 		} else {
 			task_io_account_write(bio->bi_iter.bi_size);
 		}
-		if (iocb->ki_flags & IOCB_NOWAIT)
-			bio->bi_opf |= REQ_NOWAIT;
-
 		dio->size += bio->bi_iter.bi_size;
 		pos += bio->bi_iter.bi_size;
 
diff --git a/block/genhd.c b/block/genhd.c
index 23cf83b3331c..093ef292e98f 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1016,9 +1016,8 @@ ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
 static ssize_t disk_capability_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
-	struct gendisk *disk = dev_to_disk(dev);
-
-	return sprintf(buf, "%x\n", disk->flags);
+	dev_warn_once(dev, "the capability attribute has been deprecated.\n");
+	return sprintf(buf, "0\n");
 }
 
 static ssize_t disk_alignment_offset_show(struct device *dev,