Merge branch 'for-6.12/block' into for-6.12/io_uring-discard

* for-6.12/block: (115 commits)
  block: unpin user pages belonging to a folio at once
  mm: release number of pages of a folio
  block: introduce folio awareness and add a bigger size from folio
  block: Added folio-ized version of bio_add_hw_page()
  block, bfq: factor out a helper to split bfqq in bfq_init_rq()
  block, bfq: remove local variable 'bfqq_already_existing' in bfq_init_rq()
  block, bfq: remove local variable 'split' in bfq_init_rq()
  block, bfq: remove bfq_log_bfqg()
  block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator()
  block, bfq: fix procress reference leakage for bfqq in merge chain
  block, bfq: fix uaf for accessing waker_bfqq after splitting
  blk-throttle: support prioritized processing of metadata
  blk-throttle: remove last_low_overflow_time
  drbd: Add NULL check for net_conf to prevent dereference in state validation
  blk-mq: add missing unplug trace event
  mtip32xx: Remove redundant null pointer checks in mtip_hw_debugfs_init()
  md: Add new_level sysfs interface
  zram: Shrink zram_table_entry::flags.
  zram: Remove ZRAM_LOCK
  zram: Replace bit spinlocks with a spinlock_t.
  ...

17 files changed, 410 insertions, 362 deletions

diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index b758693697c0..e831aedb4643 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -679,12 +679,7 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 		bfq_put_idle_entity(bfq_entity_service_tree(entity), entity);
 	bfqg_and_blkg_put(old_parent);
 
-	if (entity->parent &&
-	    entity->parent->last_bfqq_created == bfqq)
-		entity->parent->last_bfqq_created = NULL;
-	else if (bfqd->last_bfqq_created == bfqq)
-		bfqd->last_bfqq_created = NULL;
-
+	bfq_reassign_last_bfqq(bfqq, NULL);
 	entity->parent = bfqg->my_entity;
 	entity->sched_data = &bfqg->sched_data;
 	/* pin down bfqg and its associated blkg  */
@@ -741,7 +736,6 @@ static void bfq_sync_bfqq_move(struct bfq_data *bfqd,
 		 */
 		bfq_put_cooperator(sync_bfqq);
 		bic_set_bfqq(bic, NULL, true, act_idx);
-		bfq_release_process_ref(bfqd, sync_bfqq);
 	}
 }
 
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 36a4998c4b37..0747d9d0e48c 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -2911,8 +2911,12 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 	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)
-		return bfqq->new_bfqq;
+	new_bfqq = bfqq->new_bfqq;
+	if (new_bfqq) {
+		while (new_bfqq->new_bfqq)
+			new_bfqq = new_bfqq->new_bfqq;
+		return new_bfqq;
+	}
 
 	/*
 	 * Check delayed stable merge for rotational or non-queueing
@@ -3093,8 +3097,8 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
 }
 
 
-static void
-bfq_reassign_last_bfqq(struct bfq_queue *cur_bfqq, struct bfq_queue *new_bfqq)
+void bfq_reassign_last_bfqq(struct bfq_queue *cur_bfqq,
+			    struct bfq_queue *new_bfqq)
 {
 	if (cur_bfqq->entity.parent &&
 	    cur_bfqq->entity.parent->last_bfqq_created == cur_bfqq)
@@ -3125,10 +3129,12 @@ void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq)
 	bfq_put_queue(bfqq);
 }
 
-static void
-bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic,
-		struct bfq_queue *bfqq, struct bfq_queue *new_bfqq)
+static struct bfq_queue *bfq_merge_bfqqs(struct bfq_data *bfqd,
+					 struct bfq_io_cq *bic,
+					 struct bfq_queue *bfqq)
 {
+	struct bfq_queue *new_bfqq = bfqq->new_bfqq;
+
 	bfq_log_bfqq(bfqd, bfqq, "merging with queue %lu",
 		(unsigned long)new_bfqq->pid);
 	/* Save weight raising and idle window of the merged queues */
@@ -3222,6 +3228,8 @@ bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic,
 	bfq_reassign_last_bfqq(bfqq, new_bfqq);
 
 	bfq_release_process_ref(bfqd, bfqq);
+
+	return new_bfqq;
 }
 
 static bool bfq_allow_bio_merge(struct request_queue *q, struct request *rq,
@@ -3257,14 +3265,8 @@ static bool bfq_allow_bio_merge(struct request_queue *q, struct request *rq,
 		 * fulfilled, i.e., bic can be redirected to new_bfqq
 		 * and bfqq can be put.
 		 */
-		bfq_merge_bfqqs(bfqd, bfqd->bio_bic, bfqq,
-				new_bfqq);
-		/*
-		 * If we get here, bio will be queued into new_queue,
-		 * so use new_bfqq to decide whether bio and rq can be
-		 * merged.
-		 */
-		bfqq = new_bfqq;
+		while (bfqq != new_bfqq)
+			bfqq = bfq_merge_bfqqs(bfqd, bfqd->bio_bic, bfqq);
 
 		/*
 		 * Change also bqfd->bio_bfqq, as
@@ -5432,6 +5434,8 @@ void bfq_put_cooperator(struct bfq_queue *bfqq)
 		bfq_put_queue(__bfqq);
 		__bfqq = next;
 	}
+
+	bfq_release_process_ref(bfqq->bfqd, bfqq);
 }
 
 static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq)
@@ -5444,8 +5448,6 @@ static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq)
 	bfq_log_bfqq(bfqd, bfqq, "exit_bfqq: %p, %d", bfqq, bfqq->ref);
 
 	bfq_put_cooperator(bfqq);
-
-	bfq_release_process_ref(bfqd, bfqq);
 }
 
 static void bfq_exit_icq_bfqq(struct bfq_io_cq *bic, bool is_sync,
@@ -5701,9 +5703,7 @@ bfq_do_early_stable_merge(struct bfq_data *bfqd, struct bfq_queue *bfqq,
 	 * state before killing it.
 	 */
 	bfqq->bic = bic;
-	bfq_merge_bfqqs(bfqd, bic, bfqq, new_bfqq);
-
-	return new_bfqq;
+	return bfq_merge_bfqqs(bfqd, bic, bfqq);
 }
 
 /*
@@ -6158,6 +6158,7 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
 	bool waiting, idle_timer_disabled = false;
 
 	if (new_bfqq) {
+		struct bfq_queue *old_bfqq = bfqq;
 		/*
 		 * Release the request's reference to the old bfqq
 		 * and make sure one is taken to the shared queue.
@@ -6174,18 +6175,18 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
 		 * new_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);
+				bfq_actuator_index(bfqd, rq->bio)) == bfqq) {
+			while (bfqq != new_bfqq)
+				bfqq = bfq_merge_bfqqs(bfqd, RQ_BIC(rq), bfqq);
+		}
 
-		bfq_clear_bfqq_just_created(bfqq);
+		bfq_clear_bfqq_just_created(old_bfqq);
 		/*
 		 * rq is about to be enqueued into new_bfqq,
 		 * release rq reference on bfqq
 		 */
-		bfq_put_queue(bfqq);
+		bfq_put_queue(old_bfqq);
 		rq->elv.priv[1] = new_bfqq;
-		bfqq = new_bfqq;
 	}
 
 	bfq_update_io_thinktime(bfqd, bfqq);
@@ -6723,7 +6724,7 @@ bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq)
 {
 	bfq_log_bfqq(bfqq->bfqd, bfqq, "splitting queue");
 
-	if (bfqq_process_refs(bfqq) == 1) {
+	if (bfqq_process_refs(bfqq) == 1 && !bfqq->new_bfqq) {
 		bfqq->pid = current->pid;
 		bfq_clear_bfqq_coop(bfqq);
 		bfq_clear_bfqq_split_coop(bfqq);
@@ -6733,16 +6734,13 @@ bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq)
 	bic_set_bfqq(bic, NULL, true, bfqq->actuator_idx);
 
 	bfq_put_cooperator(bfqq);
-
-	bfq_release_process_ref(bfqq->bfqd, bfqq);
 	return NULL;
 }
 
-static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd,
-						   struct bfq_io_cq *bic,
-						   struct bio *bio,
-						   bool split, bool is_sync,
-						   bool *new_queue)
+static struct bfq_queue *
+__bfq_get_bfqq_handle_split(struct bfq_data *bfqd, struct bfq_io_cq *bic,
+			    struct bio *bio, bool split, bool is_sync,
+			    bool *new_queue)
 {
 	unsigned int act_idx = bfq_actuator_index(bfqd, bio);
 	struct bfq_queue *bfqq = bic_to_bfqq(bic, is_sync, act_idx);
@@ -6821,6 +6819,84 @@ static void bfq_prepare_request(struct request *rq)
 	rq->elv.priv[0] = rq->elv.priv[1] = NULL;
 }
 
+static struct bfq_queue *bfq_waker_bfqq(struct bfq_queue *bfqq)
+{
+	struct bfq_queue *new_bfqq = bfqq->new_bfqq;
+	struct bfq_queue *waker_bfqq = bfqq->waker_bfqq;
+
+	if (!waker_bfqq)
+		return NULL;
+
+	while (new_bfqq) {
+		if (new_bfqq == waker_bfqq) {
+			/*
+			 * If waker_bfqq is in the merge chain, and current
+			 * is the only procress.
+			 */
+			if (bfqq_process_refs(waker_bfqq) == 1)
+				return NULL;
+			break;
+		}
+
+		new_bfqq = new_bfqq->new_bfqq;
+	}
+
+	return waker_bfqq;
+}
+
+static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd,
+						   struct bfq_io_cq *bic,
+						   struct bio *bio,
+						   unsigned int idx,
+						   bool is_sync)
+{
+	struct bfq_queue *waker_bfqq;
+	struct bfq_queue *bfqq;
+	bool new_queue = false;
+
+	bfqq = __bfq_get_bfqq_handle_split(bfqd, bic, bio, false, is_sync,
+					   &new_queue);
+	if (unlikely(new_queue))
+		return bfqq;
+
+	/* If the queue was seeky for too long, break it apart. */
+	if (!bfq_bfqq_coop(bfqq) || !bfq_bfqq_split_coop(bfqq) ||
+	    bic->bfqq_data[idx].stably_merged)
+		return bfqq;
+
+	waker_bfqq = bfq_waker_bfqq(bfqq);
+
+	/* Update bic before losing reference to bfqq */
+	if (bfq_bfqq_in_large_burst(bfqq))
+		bic->bfqq_data[idx].saved_in_large_burst = true;
+
+	bfqq = bfq_split_bfqq(bic, bfqq);
+	if (bfqq) {
+		bfq_bfqq_resume_state(bfqq, bfqd, bic, true);
+		return bfqq;
+	}
+
+	bfqq = __bfq_get_bfqq_handle_split(bfqd, bic, bio, true, is_sync, NULL);
+	if (unlikely(bfqq == &bfqd->oom_bfqq))
+		return bfqq;
+
+	bfq_bfqq_resume_state(bfqq, bfqd, bic, false);
+	bfqq->waker_bfqq = waker_bfqq;
+	bfqq->tentative_waker_bfqq = NULL;
+
+	/*
+	 * If the waker queue disappears, then new_bfqq->waker_bfqq must be
+	 * reset. So insert new_bfqq into the
+	 * woken_list of the waker. See
+	 * bfq_check_waker for details.
+	 */
+	if (waker_bfqq)
+		hlist_add_head(&bfqq->woken_list_node,
+			       &bfqq->waker_bfqq->woken_list);
+
+	return bfqq;
+}
+
 /*
  * If needed, init rq, allocate bfq data structures associated with
  * rq, and increment reference counters in the destination bfq_queue
@@ -6852,8 +6928,6 @@ static struct bfq_queue *bfq_init_rq(struct request *rq)
 	struct bfq_io_cq *bic;
 	const int is_sync = rq_is_sync(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))
@@ -6870,54 +6944,9 @@ static struct bfq_queue *bfq_init_rq(struct request *rq)
 		return RQ_BFQQ(rq);
 
 	bic = icq_to_bic(rq->elv.icq);
-
 	bfq_check_ioprio_change(bic, bio);
-
 	bfq_bic_update_cgroup(bic, bio);
-
-	bfqq = bfq_get_bfqq_handle_split(bfqd, bic, bio, false, is_sync,
-					 &new_queue);
-
-	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->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->bfqq_data[a_idx].saved_in_large_burst =
-					true;
-
-			bfqq = bfq_split_bfqq(bic, bfqq);
-			split = true;
-
-			if (!bfqq) {
-				bfqq = bfq_get_bfqq_handle_split(bfqd, bic, bio,
-								 true, is_sync,
-								 NULL);
-				if (unlikely(bfqq == &bfqd->oom_bfqq))
-					bfqq_already_existing = true;
-			} else
-				bfqq_already_existing = true;
-
-			if (!bfqq_already_existing) {
-				bfqq->waker_bfqq = old_bfqq->waker_bfqq;
-				bfqq->tentative_waker_bfqq = NULL;
-
-				/*
-				 * If the waker queue disappears, then
-				 * new_bfqq->waker_bfqq must be
-				 * reset. So insert new_bfqq into the
-				 * woken_list of the waker. See
-				 * bfq_check_waker for details.
-				 */
-				if (bfqq->waker_bfqq)
-					hlist_add_head(&bfqq->woken_list_node,
-						       &bfqq->waker_bfqq->woken_list);
-			}
-		}
-	}
+	bfqq = bfq_get_bfqq_handle_split(bfqd, bic, bio, a_idx, is_sync);
 
 	bfqq_request_allocated(bfqq);
 	bfqq->ref++;
@@ -6934,18 +6963,9 @@ static struct bfq_queue *bfq_init_rq(struct request *rq)
 	 * addition, if the queue has also just been split, we have to
 	 * resume its state.
 	 */
-	if (likely(bfqq != &bfqd->oom_bfqq) && bfqq_process_refs(bfqq) == 1) {
+	if (likely(bfqq != &bfqd->oom_bfqq) && !bfqq->new_bfqq &&
+	    bfqq_process_refs(bfqq) == 1)
 		bfqq->bic = bic;
-		if (split) {
-			/*
-			 * The queue has just been split from a shared
-			 * queue: restore the idle window and the
-			 * possible weight raising period.
-			 */
-			bfq_bfqq_resume_state(bfqq, bfqd, bic,
-					      bfqq_already_existing);
-		}
-	}
 
 	/*
 	 * Consider bfqq as possibly belonging to a burst of newly
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index 08ddf2cfae5b..687a3a7ba784 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -1156,6 +1156,8 @@ void bfq_del_bfqq_busy(struct bfq_queue *bfqq, bool expiration);
 void bfq_add_bfqq_busy(struct bfq_queue *bfqq);
 void bfq_add_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq);
 void bfq_del_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq);
+void bfq_reassign_last_bfqq(struct bfq_queue *cur_bfqq,
+			    struct bfq_queue *new_bfqq);
 
 /* --------------- end of interface of B-WF2Q+ ---------------- */
 
@@ -1183,11 +1185,6 @@ struct bfq_group *bfqq_group(struct bfq_queue *bfqq);
 			"%s " fmt, pid_str, ##args);			\
 } while (0)
 
-#define bfq_log_bfqg(bfqd, bfqg, fmt, args...)	do {			\
-	blk_add_cgroup_trace_msg((bfqd)->queue,				\
-		&bfqg_to_blkg(bfqg)->blkcg->css, fmt, ##args);		\
-} while (0)
-
 #else /* CONFIG_BFQ_GROUP_IOSCHED */
 
 #define bfq_log_bfqq(bfqd, bfqq, fmt, args...) do {	\
@@ -1197,7 +1194,6 @@ struct bfq_group *bfqq_group(struct bfq_queue *bfqq);
 	bfq_bfqq_name((bfqq), pid_str, MAX_BFQQ_NAME_LENGTH);		\
 	blk_add_trace_msg((bfqd)->queue, "%s " fmt, pid_str, ##args);	\
 } while (0)
-#define bfq_log_bfqg(bfqd, bfqg, fmt, args...)		do {} while (0)
 
 #endif /* CONFIG_BFQ_GROUP_IOSCHED */
 
diff --git a/block/bio.c b/block/bio.c
index c4053d49679a..ac4d77c88932 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -931,7 +931,8 @@ static bool bvec_try_merge_page(struct bio_vec *bv, struct page *page,
 	if (!zone_device_pages_have_same_pgmap(bv->bv_page, page))
 		return false;
 
-	*same_page = ((vec_end_addr & PAGE_MASK) == page_addr);
+	*same_page = ((vec_end_addr & PAGE_MASK) == ((page_addr + off) &
+		     PAGE_MASK));
 	if (!*same_page) {
 		if (IS_ENABLED(CONFIG_KMSAN))
 			return false;
@@ -1017,6 +1018,29 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 }
 
 /**
+ * bio_add_hw_folio - attempt to add a folio to a bio with hw constraints
+ * @q: the target queue
+ * @bio: destination bio
+ * @folio: folio to add
+ * @len: vec entry length
+ * @offset: vec entry offset in the folio
+ * @max_sectors: maximum number of sectors that can be added
+ * @same_page: return if the segment has been merged inside the same folio
+ *
+ * Add a folio to a bio while respecting the hardware max_sectors, max_segment
+ * and gap limitations.
+ */
+int bio_add_hw_folio(struct request_queue *q, struct bio *bio,
+		struct folio *folio, size_t len, size_t offset,
+		unsigned int max_sectors, bool *same_page)
+{
+	if (len > UINT_MAX || offset > UINT_MAX)
+		return 0;
+	return bio_add_hw_page(q, bio, folio_page(folio, 0), len, offset,
+			       max_sectors, same_page);
+}
+
+/**
  * bio_add_pc_page	- attempt to add page to passthrough bio
  * @q: the target queue
  * @bio: destination bio
@@ -1166,7 +1190,6 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty)
 	struct folio_iter fi;
 
 	bio_for_each_folio_all(fi, bio) {
-		struct page *page;
 		size_t nr_pages;
 
 		if (mark_dirty) {
@@ -1174,12 +1197,9 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty)
 			folio_mark_dirty(fi.folio);
 			folio_unlock(fi.folio);
 		}
-		page = folio_page(fi.folio, fi.offset / PAGE_SIZE);
 		nr_pages = (fi.offset + fi.length - 1) / PAGE_SIZE -
 			   fi.offset / PAGE_SIZE + 1;
-		do {
-			bio_release_page(bio, page++);
-		} while (--nr_pages != 0);
+		unpin_user_folio(fi.folio, nr_pages);
 	}
 }
 EXPORT_SYMBOL_GPL(__bio_release_pages);
@@ -1204,8 +1224,8 @@ void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter)
 	bio_set_flag(bio, BIO_CLONED);
 }
 
-static int bio_iov_add_page(struct bio *bio, struct page *page,
-		unsigned int len, unsigned int offset)
+static int bio_iov_add_folio(struct bio *bio, struct folio *folio, size_t len,
+			     size_t offset)
 {
 	bool same_page = false;
 
@@ -1214,30 +1234,61 @@ static int bio_iov_add_page(struct bio *bio, struct page *page,
 
 	if (bio->bi_vcnt > 0 &&
 	    bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1],
-				page, len, offset, &same_page)) {
+				folio_page(folio, 0), len, offset,
+				&same_page)) {
 		bio->bi_iter.bi_size += len;
-		if (same_page)
-			bio_release_page(bio, page);
+		if (same_page && bio_flagged(bio, BIO_PAGE_PINNED))
+			unpin_user_folio(folio, 1);
 		return 0;
 	}
-	__bio_add_page(bio, page, len, offset);
+	bio_add_folio_nofail(bio, folio, len, offset);
 	return 0;
 }
 
-static int bio_iov_add_zone_append_page(struct bio *bio, struct page *page,
-		unsigned int len, unsigned int offset)
+static int bio_iov_add_zone_append_folio(struct bio *bio, struct folio *folio,
+					 size_t len, size_t offset)
 {
 	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
 	bool same_page = false;
 
-	if (bio_add_hw_page(q, bio, page, len, offset,
+	if (bio_add_hw_folio(q, bio, folio, len, offset,
 			queue_max_zone_append_sectors(q), &same_page) != len)
 		return -EINVAL;
-	if (same_page)
-		bio_release_page(bio, page);
+	if (same_page && bio_flagged(bio, BIO_PAGE_PINNED))
+		unpin_user_folio(folio, 1);
 	return 0;
 }
 
+static unsigned int get_contig_folio_len(unsigned int *num_pages,
+					 struct page **pages, unsigned int i,
+					 struct folio *folio, size_t left,
+					 size_t offset)
+{
+	size_t bytes = left;
+	size_t contig_sz = min_t(size_t, PAGE_SIZE - offset, bytes);
+	unsigned int j;
+
+	/*
+	 * We might COW a single page in the middle of
+	 * a large folio, so we have to check that all
+	 * pages belong to the same folio.
+	 */
+	bytes -= contig_sz;
+	for (j = i + 1; j < i + *num_pages; j++) {
+		size_t next = min_t(size_t, PAGE_SIZE, bytes);
+
+		if (page_folio(pages[j]) != folio ||
+		    pages[j] != pages[j - 1] + 1) {
+			break;
+		}
+		contig_sz += next;
+		bytes -= next;
+	}
+	*num_pages = j - i;
+
+	return contig_sz;
+}
+
 #define PAGE_PTRS_PER_BVEC     (sizeof(struct bio_vec) / sizeof(struct page *))
 
 /**
@@ -1257,9 +1308,9 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
 	unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt;
 	struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt;
 	struct page **pages = (struct page **)bv;
-	ssize_t size, left;
-	unsigned len, i = 0;
-	size_t offset;
+	ssize_t size;
+	unsigned int num_pages, i = 0;
+	size_t offset, folio_offset, left, len;
 	int ret = 0;
 
 	/*
@@ -1299,17 +1350,28 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
 		goto out;
 	}
 
-	for (left = size, i = 0; left > 0; left -= len, i++) {
+	for (left = size, i = 0; left > 0; left -= len, i += num_pages) {
 		struct page *page = pages[i];
+		struct folio *folio = page_folio(page);
+
+		folio_offset = ((size_t)folio_page_idx(folio, page) <<
+			       PAGE_SHIFT) + offset;
+
+		len = min(folio_size(folio) - folio_offset, left);
+
+		num_pages = DIV_ROUND_UP(offset + len, PAGE_SIZE);
+
+		if (num_pages > 1)
+			len = get_contig_folio_len(&num_pages, pages, i,
+						   folio, left, offset);
 
-		len = min_t(size_t, PAGE_SIZE - offset, left);
 		if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
-			ret = bio_iov_add_zone_append_page(bio, page, len,
-					offset);
+			ret = bio_iov_add_zone_append_folio(bio, folio, len,
+					folio_offset);
 			if (ret)
 				break;
 		} else
-			bio_iov_add_page(bio, page, len, offset);
+			bio_iov_add_folio(bio, folio, len, folio_offset);
 
 		offset = 0;
 	}
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 69e70964398c..e68c725cf8d9 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1458,7 +1458,6 @@ int blkcg_init_disk(struct gendisk *disk)
 	struct request_queue *q = disk->queue;
 	struct blkcg_gq *new_blkg, *blkg;
 	bool preloaded;
-	int ret;
 
 	new_blkg = blkg_alloc(&blkcg_root, disk, GFP_KERNEL);
 	if (!new_blkg)
@@ -1478,15 +1477,8 @@ int blkcg_init_disk(struct gendisk *disk)
 	if (preloaded)
 		radix_tree_preload_end();
 
-	ret = blk_ioprio_init(disk);
-	if (ret)
-		goto err_destroy_all;
-
 	return 0;
 
-err_destroy_all:
-	blkg_destroy_all(disk);
-	return ret;
 err_unlock:
 	spin_unlock_irq(&q->queue_lock);
 	if (preloaded)
@@ -1554,6 +1546,14 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol)
 	if (blkcg_policy_enabled(q, pol))
 		return 0;
 
+	/*
+	 * Policy is allowed to be registered without pd_alloc_fn/pd_free_fn,
+	 * for example, ioprio. Such policy will work on blkcg level, not disk
+	 * level, and don't need to be activated.
+	 */
+	if (WARN_ON_ONCE(!pol->pd_alloc_fn || !pol->pd_free_fn))
+		return -EINVAL;
+
 	if (queue_is_mq(q))
 		blk_mq_freeze_queue(q);
 retry:
@@ -1733,9 +1733,12 @@ int blkcg_policy_register(struct blkcg_policy *pol)
 		goto err_unlock;
 	}
 
-	/* Make sure cpd/pd_alloc_fn and cpd/pd_free_fn in pairs */
+	/*
+	 * Make sure cpd/pd_alloc_fn and cpd/pd_free_fn in pairs, and policy
+	 * without pd_alloc_fn/pd_free_fn can't be activated.
+	 */
 	if ((!pol->cpd_alloc_fn ^ !pol->cpd_free_fn) ||
-		(!pol->pd_alloc_fn ^ !pol->pd_free_fn))
+	    (!pol->pd_alloc_fn ^ !pol->pd_free_fn))
 		goto err_unlock;
 
 	/* register @pol */
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 864fad4a850b..b9e3265c1eb3 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -485,7 +485,6 @@ static inline void blkcg_deactivate_policy(struct gendisk *disk,
 static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg,
 						  struct blkcg_policy *pol) { return NULL; }
 static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) { return NULL; }
-static inline char *blkg_path(struct blkcg_gq *blkg) { return NULL; }
 static inline void blkg_get(struct blkcg_gq *blkg) { }
 static inline void blkg_put(struct blkcg_gq *blkg) { }
 static inline void blkcg_bio_issue_init(struct bio *bio) { }
diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 690ca99dfaca..5a6098a3db57 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -2076,7 +2076,7 @@ static void ioc_forgive_debts(struct ioc *ioc, u64 usage_us_sum, int nr_debtors,
 			      struct ioc_now *now)
 {
 	struct ioc_gq *iocg;
-	u64 dur, usage_pct, nr_cycles;
+	u64 dur, usage_pct, nr_cycles, nr_cycles_shift;
 
 	/* if no debtor, reset the cycle */
 	if (!nr_debtors) {
@@ -2138,10 +2138,12 @@ static void ioc_forgive_debts(struct ioc *ioc, u64 usage_us_sum, int nr_debtors,
 		old_debt = iocg->abs_vdebt;
 		old_delay = iocg->delay;
 
+		nr_cycles_shift = min_t(u64, nr_cycles, BITS_PER_LONG - 1);
 		if (iocg->abs_vdebt)
-			iocg->abs_vdebt = iocg->abs_vdebt >> nr_cycles ?: 1;
+			iocg->abs_vdebt = iocg->abs_vdebt >> nr_cycles_shift ?: 1;
+
 		if (iocg->delay)
-			iocg->delay = iocg->delay >> nr_cycles ?: 1;
+			iocg->delay = iocg->delay >> nr_cycles_shift ?: 1;
 
 		iocg_kick_waitq(iocg, true, now);
 
diff --git a/block/blk-ioprio.c b/block/blk-ioprio.c
index 4051fada01f1..8fff7ccc0ac7 100644
--- a/block/blk-ioprio.c
+++ b/block/blk-ioprio.c
@@ -50,14 +50,6 @@ static const char *policy_name[] = {
 static struct blkcg_policy ioprio_policy;
 
 /**
- * struct ioprio_blkg - Per (cgroup, request queue) data.
- * @pd: blkg_policy_data structure.
- */
-struct ioprio_blkg {
-	struct blkg_policy_data pd;
-};
-
-/**
  * struct ioprio_blkcg - Per cgroup data.
  * @cpd: blkcg_policy_data structure.
  * @prio_policy: One of the IOPRIO_CLASS_* values. See also <linux/ioprio.h>.
@@ -67,11 +59,6 @@ struct ioprio_blkcg {
 	enum prio_policy	 prio_policy;
 };
 
-static inline struct ioprio_blkg *pd_to_ioprio(struct blkg_policy_data *pd)
-{
-	return pd ? container_of(pd, struct ioprio_blkg, pd) : NULL;
-}
-
 static struct ioprio_blkcg *blkcg_to_ioprio_blkcg(struct blkcg *blkcg)
 {
 	return container_of(blkcg_to_cpd(blkcg, &ioprio_policy),
@@ -84,16 +71,6 @@ ioprio_blkcg_from_css(struct cgroup_subsys_state *css)
 	return blkcg_to_ioprio_blkcg(css_to_blkcg(css));
 }
 
-static struct ioprio_blkcg *ioprio_blkcg_from_bio(struct bio *bio)
-{
-	struct blkg_policy_data *pd = blkg_to_pd(bio->bi_blkg, &ioprio_policy);
-
-	if (!pd)
-		return NULL;
-
-	return blkcg_to_ioprio_blkcg(pd->blkg->blkcg);
-}
-
 static int ioprio_show_prio_policy(struct seq_file *sf, void *v)
 {
 	struct ioprio_blkcg *blkcg = ioprio_blkcg_from_css(seq_css(sf));
@@ -118,25 +95,6 @@ static ssize_t ioprio_set_prio_policy(struct kernfs_open_file *of, char *buf,
 	return nbytes;
 }
 
-static struct blkg_policy_data *
-ioprio_alloc_pd(struct gendisk *disk, struct blkcg *blkcg, gfp_t gfp)
-{
-	struct ioprio_blkg *ioprio_blkg;
-
-	ioprio_blkg = kzalloc(sizeof(*ioprio_blkg), gfp);
-	if (!ioprio_blkg)
-		return NULL;
-
-	return &ioprio_blkg->pd;
-}
-
-static void ioprio_free_pd(struct blkg_policy_data *pd)
-{
-	struct ioprio_blkg *ioprio_blkg = pd_to_ioprio(pd);
-
-	kfree(ioprio_blkg);
-}
-
 static struct blkcg_policy_data *ioprio_alloc_cpd(gfp_t gfp)
 {
 	struct ioprio_blkcg *blkcg;
@@ -179,14 +137,11 @@ static struct blkcg_policy ioprio_policy = {
 
 	.cpd_alloc_fn	= ioprio_alloc_cpd,
 	.cpd_free_fn	= ioprio_free_cpd,
-
-	.pd_alloc_fn	= ioprio_alloc_pd,
-	.pd_free_fn	= ioprio_free_pd,
 };
 
 void blkcg_set_ioprio(struct bio *bio)
 {
-	struct ioprio_blkcg *blkcg = ioprio_blkcg_from_bio(bio);
+	struct ioprio_blkcg *blkcg = blkcg_to_ioprio_blkcg(bio->bi_blkg->blkcg);
 	u16 prio;
 
 	if (!blkcg || blkcg->prio_policy == POLICY_NO_CHANGE)
@@ -219,16 +174,6 @@ void blkcg_set_ioprio(struct bio *bio)
 		bio->bi_ioprio = prio;
 }
 
-void blk_ioprio_exit(struct gendisk *disk)
-{
-	blkcg_deactivate_policy(disk, &ioprio_policy);
-}
-
-int blk_ioprio_init(struct gendisk *disk)
-{
-	return blkcg_activate_policy(disk, &ioprio_policy);
-}
-
 static int __init ioprio_init(void)
 {
 	return blkcg_policy_register(&ioprio_policy);
diff --git a/block/blk-ioprio.h b/block/blk-ioprio.h
index b6afb8e80de0..9265143f9bc9 100644
--- a/block/blk-ioprio.h
+++ b/block/blk-ioprio.h
@@ -9,17 +9,8 @@ struct request_queue;
 struct bio;
 
 #ifdef CONFIG_BLK_CGROUP_IOPRIO
-int blk_ioprio_init(struct gendisk *disk);
-void blk_ioprio_exit(struct gendisk *disk);
 void blkcg_set_ioprio(struct bio *bio);
 #else
-static inline int blk_ioprio_init(struct gendisk *disk)
-{
-	return 0;
-}
-static inline void blk_ioprio_exit(struct gendisk *disk)
-{
-}
 static inline void blkcg_set_ioprio(struct bio *bio)
 {
 }
diff --git a/block/blk-merge.c b/block/blk-merge.c
index de5281bcadc5..56769c4bcd79 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -105,9 +105,33 @@ static unsigned int bio_allowed_max_sectors(const struct queue_limits *lim)
 	return round_down(UINT_MAX, lim->logical_block_size) >> SECTOR_SHIFT;
 }
 
-static struct bio *bio_split_discard(struct bio *bio,
-				     const struct queue_limits *lim,
-				     unsigned *nsegs, struct bio_set *bs)
+static struct bio *bio_submit_split(struct bio *bio, int split_sectors)
+{
+	if (unlikely(split_sectors < 0)) {
+		bio->bi_status = errno_to_blk_status(split_sectors);
+		bio_endio(bio);
+		return NULL;
+	}
+
+	if (split_sectors) {
+		struct bio *split;
+
+		split = bio_split(bio, split_sectors, GFP_NOIO,
+				&bio->bi_bdev->bd_disk->bio_split);
+		split->bi_opf |= REQ_NOMERGE;
+		blkcg_bio_issue_init(split);
+		bio_chain(split, bio);
+		trace_block_split(split, bio->bi_iter.bi_sector);
+		WARN_ON_ONCE(bio_zone_write_plugging(bio));
+		submit_bio_noacct(bio);
+		return split;
+	}
+
+	return bio;
+}
+
+struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
+		unsigned *nsegs)
 {
 	unsigned int max_discard_sectors, granularity;
 	sector_t tmp;
@@ -121,10 +145,10 @@ static struct bio *bio_split_discard(struct bio *bio,
 		min(lim->max_discard_sectors, bio_allowed_max_sectors(lim));
 	max_discard_sectors -= max_discard_sectors % granularity;
 	if (unlikely(!max_discard_sectors))
-		return NULL;
+		return bio;
 
 	if (bio_sectors(bio) <= max_discard_sectors)
-		return NULL;
+		return bio;
 
 	split_sectors = max_discard_sectors;
 
@@ -139,19 +163,18 @@ static struct bio *bio_split_discard(struct bio *bio,
 	if (split_sectors > tmp)
 		split_sectors -= tmp;
 
-	return bio_split(bio, split_sectors, GFP_NOIO, bs);
+	return bio_submit_split(bio, split_sectors);
 }
 
-static struct bio *bio_split_write_zeroes(struct bio *bio,
-					  const struct queue_limits *lim,
-					  unsigned *nsegs, struct bio_set *bs)
+struct bio *bio_split_write_zeroes(struct bio *bio,
+		const struct queue_limits *lim, unsigned *nsegs)
 {
 	*nsegs = 0;
 	if (!lim->max_write_zeroes_sectors)
-		return NULL;
+		return bio;
 	if (bio_sectors(bio) <= lim->max_write_zeroes_sectors)
-		return NULL;
-	return bio_split(bio, lim->max_write_zeroes_sectors, GFP_NOIO, bs);
+		return bio;
+	return bio_submit_split(bio, lim->max_write_zeroes_sectors);
 }
 
 static inline unsigned int blk_boundary_sectors(const struct queue_limits *lim,
@@ -274,27 +297,19 @@ static bool bvec_split_segs(const struct queue_limits *lim,
 }
 
 /**
- * bio_split_rw - split a bio in two bios
+ * bio_split_rw_at - check if and where to split a read/write bio
  * @bio:  [in] bio to be split
  * @lim:  [in] queue limits to split based on
  * @segs: [out] number of segments in the bio with the first half of the sectors
- * @bs:	  [in] bio set to allocate the clone from
  * @max_bytes: [in] maximum number of bytes per bio
  *
- * Clone @bio, update the bi_iter of the clone to represent the first sectors
- * of @bio and update @bio->bi_iter to represent the remaining sectors. The
- * following is guaranteed for the cloned bio:
- * - That it has at most @max_bytes worth of data
- * - That it has at most queue_max_segments(@q) segments.
- *
- * Except for discard requests the cloned bio will point at the bi_io_vec of
- * the original bio. It is the responsibility of the caller to ensure that the
- * original bio is not freed before the cloned bio. The caller is also
- * responsible for ensuring that @bs is only destroyed after processing of the
- * split bio has finished.
+ * Find out if @bio needs to be split to fit the queue limits in @lim and a
+ * maximum size of @max_bytes.  Returns a negative error number if @bio can't be
+ * split, 0 if the bio doesn't have to be split, or a positive sector offset if
+ * @bio needs to be split.
  */
-struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
-		unsigned *segs, struct bio_set *bs, unsigned max_bytes)
+int bio_split_rw_at(struct bio *bio, const struct queue_limits *lim,
+		unsigned *segs, unsigned max_bytes)
 {
 	struct bio_vec bv, bvprv, *bvprvp = NULL;
 	struct bvec_iter iter;
@@ -324,22 +339,17 @@ struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
 	}
 
 	*segs = nsegs;
-	return NULL;
+	return 0;
 split:
-	if (bio->bi_opf & REQ_ATOMIC) {
-		bio->bi_status = BLK_STS_INVAL;
-		bio_endio(bio);
-		return ERR_PTR(-EINVAL);
-	}
+	if (bio->bi_opf & REQ_ATOMIC)
+		return -EINVAL;
+
 	/*
 	 * We can't sanely support splitting for a REQ_NOWAIT bio. End it
 	 * with EAGAIN if splitting is required and return an error pointer.
 	 */
-	if (bio->bi_opf & REQ_NOWAIT) {
-		bio->bi_status = BLK_STS_AGAIN;
-		bio_endio(bio);
-		return ERR_PTR(-EAGAIN);
-	}
+	if (bio->bi_opf & REQ_NOWAIT)
+		return -EAGAIN;
 
 	*segs = nsegs;
 
@@ -356,58 +366,36 @@ split:
 	 * big IO can be trival, disable iopoll when split needed.
 	 */
 	bio_clear_polled(bio);
-	return bio_split(bio, bytes >> SECTOR_SHIFT, GFP_NOIO, bs);
+	return bytes >> SECTOR_SHIFT;
 }
-EXPORT_SYMBOL_GPL(bio_split_rw);
+EXPORT_SYMBOL_GPL(bio_split_rw_at);
 
-/**
- * __bio_split_to_limits - split a bio to fit the queue limits
- * @bio:     bio to be split
- * @lim:     queue limits to split based on
- * @nr_segs: returns the number of segments in the returned bio
- *
- * Check if @bio needs splitting based on the queue limits, and if so split off
- * a bio fitting the limits from the beginning of @bio and return it.  @bio is
- * shortened to the remainder and re-submitted.
+struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
+		unsigned *nr_segs)
+{
+	return bio_submit_split(bio,
+		bio_split_rw_at(bio, lim, nr_segs,
+			get_max_io_size(bio, lim) << SECTOR_SHIFT));
+}
+
+/*
+ * REQ_OP_ZONE_APPEND bios must never be split by the block layer.
  *
- * The split bio is allocated from @q->bio_split, which is provided by the
- * block layer.
+ * But we want the nr_segs calculation provided by bio_split_rw_at, and having
+ * a good sanity check that the submitter built the bio correctly is nice to
+ * have as well.
  */
-struct bio *__bio_split_to_limits(struct bio *bio,
-				  const struct queue_limits *lim,
-				  unsigned int *nr_segs)
+struct bio *bio_split_zone_append(struct bio *bio,
+		const struct queue_limits *lim, unsigned *nr_segs)
 {
-	struct bio_set *bs = &bio->bi_bdev->bd_disk->bio_split;
-	struct bio *split;
-
-	switch (bio_op(bio)) {
-	case REQ_OP_DISCARD:
-	case REQ_OP_SECURE_ERASE:
-		split = bio_split_discard(bio, lim, nr_segs, bs);
-		break;
-	case REQ_OP_WRITE_ZEROES:
-		split = bio_split_write_zeroes(bio, lim, nr_segs, bs);
-		break;
-	default:
-		split = bio_split_rw(bio, lim, nr_segs, bs,
-				get_max_io_size(bio, lim) << SECTOR_SHIFT);
-		if (IS_ERR(split))
-			return NULL;
-		break;
-	}
-
-	if (split) {
-		/* there isn't chance to merge the split bio */
-		split->bi_opf |= REQ_NOMERGE;
-
-		blkcg_bio_issue_init(split);
-		bio_chain(split, bio);
-		trace_block_split(split, bio->bi_iter.bi_sector);
-		WARN_ON_ONCE(bio_zone_write_plugging(bio));
-		submit_bio_noacct(bio);
-		return split;
-	}
-	return bio;
+	unsigned int max_sectors = queue_limits_max_zone_append_sectors(lim);
+	int split_sectors;
+
+	split_sectors = bio_split_rw_at(bio, lim, nr_segs,
+			max_sectors << SECTOR_SHIFT);
+	if (WARN_ON_ONCE(split_sectors > 0))
+		split_sectors = -EINVAL;
+	return bio_submit_split(bio, split_sectors);
 }
 
 /**
@@ -426,9 +414,7 @@ struct bio *bio_split_to_limits(struct bio *bio)
 	const struct queue_limits *lim = &bdev_get_queue(bio->bi_bdev)->limits;
 	unsigned int nr_segs;
 
-	if (bio_may_exceed_limits(bio, lim))
-		return __bio_split_to_limits(bio, lim, &nr_segs);
-	return bio;
+	return __bio_split_to_limits(bio, lim, &nr_segs);
 }
 EXPORT_SYMBOL(bio_split_to_limits);
 
diff --git a/block/blk-mq.c b/block/blk-mq.c
index e3c3c0c21b55..3f1f7d0b3ff3 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2753,6 +2753,7 @@ static void blk_mq_dispatch_plug_list(struct blk_plug *plug, bool from_sched)
 void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 {
 	struct request *rq;
+	unsigned int depth;
 
 	/*
 	 * We may have been called recursively midway through handling
@@ -2763,6 +2764,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 	 */
 	if (plug->rq_count == 0)
 		return;
+	depth = plug->rq_count;
 	plug->rq_count = 0;
 
 	if (!plug->multiple_queues && !plug->has_elevator && !from_schedule) {
@@ -2770,6 +2772,7 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 
 		rq = rq_list_peek(&plug->mq_list);
 		q = rq->q;
+		trace_block_unplug(q, depth, true);
 
 		/*
 		 * Peek first request and see if we have a ->queue_rqs() hook.
@@ -2939,7 +2942,7 @@ void blk_mq_submit_bio(struct bio *bio)
 	struct blk_plug *plug = current->plug;
 	const int is_sync = op_is_sync(bio->bi_opf);
 	struct blk_mq_hw_ctx *hctx;
-	unsigned int nr_segs = 1;
+	unsigned int nr_segs;
 	struct request *rq;
 	blk_status_t ret;
 
@@ -2981,11 +2984,10 @@ void blk_mq_submit_bio(struct bio *bio)
 		goto queue_exit;
 	}
 
-	if (unlikely(bio_may_exceed_limits(bio, &q->limits))) {
-		bio = __bio_split_to_limits(bio, &q->limits, &nr_segs);
-		if (!bio)
-			goto queue_exit;
-	}
+	bio = __bio_split_to_limits(bio, &q->limits, &nr_segs);
+	if (!bio)
+		goto queue_exit;
+
 	if (!bio_integrity_prep(bio))
 		goto queue_exit;
 
diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c
index dd7310c94713..2cfb297d9a62 100644
--- a/block/blk-rq-qos.c
+++ b/block/blk-rq-qos.c
@@ -263,7 +263,7 @@ void rq_qos_wait(struct rq_wait *rqw, void *private_data,
 	has_sleeper = !prepare_to_wait_exclusive(&rqw->wait, &data.wq,
 						 TASK_UNINTERRUPTIBLE);
 	do {
-		/* The memory barrier in set_task_state saves us here. */
+		/* The memory barrier in set_current_state saves us here. */
 		if (data.got_token)
 			break;
 		if (!has_sleeper && acquire_inflight_cb(rqw, private_data)) {
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 6943ec720f39..2c4192e12efa 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1584,6 +1584,22 @@ void blk_throtl_cancel_bios(struct gendisk *disk)
 	spin_unlock_irq(&q->queue_lock);
 }
 
+static bool tg_within_limit(struct throtl_grp *tg, struct bio *bio, bool rw)
+{
+	/* throtl is FIFO - if bios are already queued, should queue */
+	if (tg->service_queue.nr_queued[rw])
+		return false;
+
+	return tg_may_dispatch(tg, bio, NULL);
+}
+
+static void tg_dispatch_in_debt(struct throtl_grp *tg, struct bio *bio, bool rw)
+{
+	if (!bio_flagged(bio, BIO_BPS_THROTTLED))
+		tg->carryover_bytes[rw] -= throtl_bio_data_size(bio);
+	tg->carryover_ios[rw]--;
+}
+
 bool __blk_throtl_bio(struct bio *bio)
 {
 	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
@@ -1600,34 +1616,35 @@ bool __blk_throtl_bio(struct bio *bio)
 	sq = &tg->service_queue;
 
 	while (true) {
-		if (tg->last_low_overflow_time[rw] == 0)
-			tg->last_low_overflow_time[rw] = jiffies;
-		/* throtl is FIFO - if bios are already queued, should queue */
-		if (sq->nr_queued[rw])
-			break;
-
-		/* if above limits, break to queue */
-		if (!tg_may_dispatch(tg, bio, NULL)) {
-			tg->last_low_overflow_time[rw] = jiffies;
+		if (tg_within_limit(tg, bio, rw)) {
+			/* within limits, let's charge and dispatch directly */
+			throtl_charge_bio(tg, bio);
+
+			/*
+			 * We need to trim slice even when bios are not being
+			 * queued otherwise it might happen that a bio is not
+			 * queued for a long time and slice keeps on extending
+			 * and trim is not called for a long time. Now if limits
+			 * are reduced suddenly we take into account all the IO
+			 * dispatched so far at new low rate and * newly queued
+			 * IO gets a really long dispatch time.
+			 *
+			 * So keep on trimming slice even if bio is not queued.
+			 */
+			throtl_trim_slice(tg, rw);
+		} else if (bio_issue_as_root_blkg(bio)) {
+			/*
+			 * IOs which may cause priority inversions are
+			 * dispatched directly, even if they're over limit.
+			 * Debts are handled by carryover_bytes/ios while
+			 * calculating wait time.
+			 */
+			tg_dispatch_in_debt(tg, bio, rw);
+		} else {
+			/* if above limits, break to queue */
 			break;
 		}
 
-		/* within limits, let's charge and dispatch directly */
-		throtl_charge_bio(tg, bio);
-
-		/*
-		 * We need to trim slice even when bios are not being queued
-		 * otherwise it might happen that a bio is not queued for
-		 * a long time and slice keeps on extending and trim is not
-		 * called for a long time. Now if limits are reduced suddenly
-		 * we take into account all the IO dispatched so far at new
-		 * low rate and * newly queued IO gets a really long dispatch
-		 * time.
-		 *
-		 * So keep on trimming slice even if bio is not queued.
-		 */
-		throtl_trim_slice(tg, rw);
-
 		/*
 		 * @bio passed through this layer without being throttled.
 		 * Climb up the ladder.  If we're already at the top, it
@@ -1650,8 +1667,6 @@ bool __blk_throtl_bio(struct bio *bio)
 		   tg->io_disp[rw], tg_iops_limit(tg, rw),
 		   sq->nr_queued[READ], sq->nr_queued[WRITE]);
 
-	tg->last_low_overflow_time[rw] = jiffies;
-
 	td->nr_queued[rw]++;
 	throtl_add_bio_tg(bio, qn, tg);
 	throttled = true;
diff --git a/block/blk-throttle.h b/block/blk-throttle.h
index 4d9ef5abdf21..1a36d1278eea 100644
--- a/block/blk-throttle.h
+++ b/block/blk-throttle.h
@@ -106,8 +106,6 @@ struct throtl_grp {
 	/* Number of bio's dispatched in current slice */
 	unsigned int io_disp[2];
 
-	unsigned long last_low_overflow_time[2];
-
 	uint64_t last_bytes_disp[2];
 	unsigned int last_io_disp[2];
 
diff --git a/block/blk.h b/block/blk.h
index e180863f918b..86affb583eb6 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -331,33 +331,67 @@ ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
 ssize_t part_timeout_store(struct device *, struct device_attribute *,
 				const char *, size_t);
 
-static inline bool bio_may_exceed_limits(struct bio *bio,
-					 const struct queue_limits *lim)
+struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
+		unsigned *nsegs);
+struct bio *bio_split_write_zeroes(struct bio *bio,
+		const struct queue_limits *lim, unsigned *nsegs);
+struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
+		unsigned *nr_segs);
+struct bio *bio_split_zone_append(struct bio *bio,
+		const struct queue_limits *lim, unsigned *nr_segs);
+
+/*
+ * All drivers must accept single-segments bios that are smaller than PAGE_SIZE.
+ *
+ * This is a quick and dirty check that relies on the fact that bi_io_vec[0] is
+ * always valid if a bio has data.  The check might lead to occasional false
+ * positives when bios are cloned, but compared to the performance impact of
+ * cloned bios themselves the loop below doesn't matter anyway.
+ */
+static inline bool bio_may_need_split(struct bio *bio,
+		const struct queue_limits *lim)
+{
+	return lim->chunk_sectors || bio->bi_vcnt != 1 ||
+		bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
+}
+
+/**
+ * __bio_split_to_limits - split a bio to fit the queue limits
+ * @bio:     bio to be split
+ * @lim:     queue limits to split based on
+ * @nr_segs: returns the number of segments in the returned bio
+ *
+ * Check if @bio needs splitting based on the queue limits, and if so split off
+ * a bio fitting the limits from the beginning of @bio and return it.  @bio is
+ * shortened to the remainder and re-submitted.
+ *
+ * The split bio is allocated from @q->bio_split, which is provided by the
+ * block layer.
+ */
+static inline struct bio *__bio_split_to_limits(struct bio *bio,
+		const struct queue_limits *lim, unsigned int *nr_segs)
 {
 	switch (bio_op(bio)) {
+	case REQ_OP_READ:
+	case REQ_OP_WRITE:
+		if (bio_may_need_split(bio, lim))
+			return bio_split_rw(bio, lim, nr_segs);
+		*nr_segs = 1;
+		return bio;
+	case REQ_OP_ZONE_APPEND:
+		return bio_split_zone_append(bio, lim, nr_segs);
 	case REQ_OP_DISCARD:
 	case REQ_OP_SECURE_ERASE:
+		return bio_split_discard(bio, lim, nr_segs);
 	case REQ_OP_WRITE_ZEROES:
-		return true; /* non-trivial splitting decisions */
+		return bio_split_write_zeroes(bio, lim, nr_segs);
 	default:
-		break;
+		/* other operations can't be split */
+		*nr_segs = 0;
+		return bio;
 	}
-
-	/*
-	 * All drivers must accept single-segments bios that are <= PAGE_SIZE.
-	 * This is a quick and dirty check that relies on the fact that
-	 * bi_io_vec[0] is always valid if a bio has data.  The check might
-	 * lead to occasional false negatives when bios are cloned, but compared
-	 * to the performance impact of cloned bios themselves the loop below
-	 * doesn't matter anyway.
-	 */
-	return lim->chunk_sectors || bio->bi_vcnt != 1 ||
-		bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
 }
 
-struct bio *__bio_split_to_limits(struct bio *bio,
-				  const struct queue_limits *lim,
-				  unsigned int *nr_segs);
 int ll_back_merge_fn(struct request *req, struct bio *bio,
 		unsigned int nr_segs);
 bool blk_attempt_req_merge(struct request_queue *q, struct request *rq,
@@ -540,6 +574,10 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 		struct page *page, unsigned int len, unsigned int offset,
 		unsigned int max_sectors, bool *same_page);
 
+int bio_add_hw_folio(struct request_queue *q, struct bio *bio,
+		struct folio *folio, size_t len, size_t offset,
+		unsigned int max_sectors, bool *same_page);
+
 /*
  * Clean up a page appropriately, where the page may be pinned, may have a
  * ref taken on it or neither.
diff --git a/block/ioctl.c b/block/ioctl.c
index e8e4a4190f18..44257bdfeacb 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -126,7 +126,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
 		return -EINVAL;
 
 	filemap_invalidate_lock(bdev->bd_mapping);
-	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
+	err = truncate_bdev_range(bdev, mode, start, end - 1);
 	if (err)
 		goto fail;
 
@@ -163,7 +163,7 @@ fail:
 static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
 		void __user *argp)
 {
-	uint64_t start, len;
+	uint64_t start, len, end;
 	uint64_t range[2];
 	int err;
 
@@ -178,11 +178,12 @@ static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
 	len = range[1];
 	if ((start & 511) || (len & 511))
 		return -EINVAL;
-	if (start + len > bdev_nr_bytes(bdev))
+	if (check_add_overflow(start, len, &end) ||
+	    end > bdev_nr_bytes(bdev))
 		return -EINVAL;
 
 	filemap_invalidate_lock(bdev->bd_mapping);
-	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
+	err = truncate_bdev_range(bdev, mode, start, end - 1);
 	if (!err)
 		err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9,
 						GFP_KERNEL);
diff --git a/block/t10-pi.c b/block/t10-pi.c
index 425e2836f3e1..e7052a728966 100644
--- a/block/t10-pi.c
+++ b/block/t10-pi.c
@@ -8,7 +8,6 @@
 #include <linux/blk-integrity.h>
 #include <linux/crc-t10dif.h>
 #include <linux/crc64.h>
-#include <linux/module.h>
 #include <net/checksum.h>
 #include <asm/unaligned.h>
 #include "blk.h"
@@ -240,9 +239,9 @@ static void ext_pi_crc64_generate(struct blk_integrity_iter *iter,
 	}
 }
 
-static bool ext_pi_ref_escape(u8 *ref_tag)
+static bool ext_pi_ref_escape(const u8 ref_tag[6])
 {
-	static u8 ref_escape[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+	static const u8 ref_escape[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 
 	return memcmp(ref_tag, ref_escape, sizeof(ref_escape)) == 0;
 }
@@ -472,6 +471,3 @@ void blk_integrity_complete(struct request *rq, unsigned int nr_bytes)
 	else
 		t10_pi_type1_complete(rq, nr_bytes);
 }
-
-MODULE_DESCRIPTION("T10 Protection Information module");
-MODULE_LICENSE("GPL");