Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 676 insertions, 0 deletions

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
new file mode 100644
index 000000000..9eb968e14
--- /dev/null
+++ b/block/blk-mq-tag.c
@@ -0,0 +1,676 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Tag allocation using scalable bitmaps. Uses active queue tracking to support
+ * fairer distribution of tags between multiple submitters when a shared tag map
+ * is used.
+ *
+ * Copyright (C) 2013-2014 Jens Axboe
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/blk-mq.h>
+#include <linux/delay.h>
+#include "blk.h"
+#include "blk-mq.h"
+#include "blk-mq-sched.h"
+#include "blk-mq-tag.h"
+
+/*
+ * Recalculate wakeup batch when tag is shared by hctx.
+ */
+static void blk_mq_update_wake_batch(struct blk_mq_tags *tags,
+		unsigned int users)
+{
+	if (!users)
+		return;
+
+	sbitmap_queue_recalculate_wake_batch(&tags->bitmap_tags,
+			users);
+	sbitmap_queue_recalculate_wake_batch(&tags->breserved_tags,
+			users);
+}
+
+/*
+ * If a previously inactive queue goes active, bump the active user count.
+ * We need to do this before try to allocate driver tag, then even if fail
+ * to get tag when first time, the other shared-tag users could reserve
+ * budget for it.
+ */
+void __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
+{
+	unsigned int users;
+
+	if (blk_mq_is_shared_tags(hctx->flags)) {
+		struct request_queue *q = hctx->queue;
+
+		if (test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags))
+			return;
+		set_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags);
+	} else {
+		if (test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
+			return;
+		set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state);
+	}
+
+	users = atomic_inc_return(&hctx->tags->active_queues);
+
+	blk_mq_update_wake_batch(hctx->tags, users);
+}
+
+/*
+ * Wakeup all potentially sleeping on tags
+ */
+void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool include_reserve)
+{
+	sbitmap_queue_wake_all(&tags->bitmap_tags);
+	if (include_reserve)
+		sbitmap_queue_wake_all(&tags->breserved_tags);
+}
+
+/*
+ * If a previously busy queue goes inactive, potential waiters could now
+ * be allowed to queue. Wake them up and check.
+ */
+void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
+{
+	struct blk_mq_tags *tags = hctx->tags;
+	unsigned int users;
+
+	if (blk_mq_is_shared_tags(hctx->flags)) {
+		struct request_queue *q = hctx->queue;
+
+		if (!test_and_clear_bit(QUEUE_FLAG_HCTX_ACTIVE,
+					&q->queue_flags))
+			return;
+	} else {
+		if (!test_and_clear_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
+			return;
+	}
+
+	users = atomic_dec_return(&tags->active_queues);
+
+	blk_mq_update_wake_batch(tags, users);
+
+	blk_mq_tag_wakeup_all(tags, false);
+}
+
+static int __blk_mq_get_tag(struct blk_mq_alloc_data *data,
+			    struct sbitmap_queue *bt)
+{
+	if (!data->q->elevator && !(data->flags & BLK_MQ_REQ_RESERVED) &&
+			!hctx_may_queue(data->hctx, bt))
+		return BLK_MQ_NO_TAG;
+
+	if (data->shallow_depth)
+		return sbitmap_queue_get_shallow(bt, data->shallow_depth);
+	else
+		return __sbitmap_queue_get(bt);
+}
+
+unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags,
+			      unsigned int *offset)
+{
+	struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
+	struct sbitmap_queue *bt = &tags->bitmap_tags;
+	unsigned long ret;
+
+	if (data->shallow_depth ||data->flags & BLK_MQ_REQ_RESERVED ||
+	    data->hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
+		return 0;
+	ret = __sbitmap_queue_get_batch(bt, nr_tags, offset);
+	*offset += tags->nr_reserved_tags;
+	return ret;
+}
+
+unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
+{
+	struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
+	struct sbitmap_queue *bt;
+	struct sbq_wait_state *ws;
+	DEFINE_SBQ_WAIT(wait);
+	unsigned int tag_offset;
+	int tag;
+
+	if (data->flags & BLK_MQ_REQ_RESERVED) {
+		if (unlikely(!tags->nr_reserved_tags)) {
+			WARN_ON_ONCE(1);
+			return BLK_MQ_NO_TAG;
+		}
+		bt = &tags->breserved_tags;
+		tag_offset = 0;
+	} else {
+		bt = &tags->bitmap_tags;
+		tag_offset = tags->nr_reserved_tags;
+	}
+
+	tag = __blk_mq_get_tag(data, bt);
+	if (tag != BLK_MQ_NO_TAG)
+		goto found_tag;
+
+	if (data->flags & BLK_MQ_REQ_NOWAIT)
+		return BLK_MQ_NO_TAG;
+
+	ws = bt_wait_ptr(bt, data->hctx);
+	do {
+		struct sbitmap_queue *bt_prev;
+
+		/*
+		 * We're out of tags on this hardware queue, kick any
+		 * pending IO submits before going to sleep waiting for
+		 * some to complete.
+		 */
+		blk_mq_run_hw_queue(data->hctx, false);
+
+		/*
+		 * Retry tag allocation after running the hardware queue,
+		 * as running the queue may also have found completions.
+		 */
+		tag = __blk_mq_get_tag(data, bt);
+		if (tag != BLK_MQ_NO_TAG)
+			break;
+
+		sbitmap_prepare_to_wait(bt, ws, &wait, TASK_UNINTERRUPTIBLE);
+
+		tag = __blk_mq_get_tag(data, bt);
+		if (tag != BLK_MQ_NO_TAG)
+			break;
+
+		bt_prev = bt;
+		io_schedule();
+
+		sbitmap_finish_wait(bt, ws, &wait);
+
+		data->ctx = blk_mq_get_ctx(data->q);
+		data->hctx = blk_mq_map_queue(data->q, data->cmd_flags,
+						data->ctx);
+		tags = blk_mq_tags_from_data(data);
+		if (data->flags & BLK_MQ_REQ_RESERVED)
+			bt = &tags->breserved_tags;
+		else
+			bt = &tags->bitmap_tags;
+
+		/*
+		 * If destination hw queue is changed, fake wake up on
+		 * previous queue for compensating the wake up miss, so
+		 * other allocations on previous queue won't be starved.
+		 */
+		if (bt != bt_prev)
+			sbitmap_queue_wake_up(bt_prev, 1);
+
+		ws = bt_wait_ptr(bt, data->hctx);
+	} while (1);
+
+	sbitmap_finish_wait(bt, ws, &wait);
+
+found_tag:
+	/*
+	 * Give up this allocation if the hctx is inactive.  The caller will
+	 * retry on an active hctx.
+	 */
+	if (unlikely(test_bit(BLK_MQ_S_INACTIVE, &data->hctx->state))) {
+		blk_mq_put_tag(tags, data->ctx, tag + tag_offset);
+		return BLK_MQ_NO_TAG;
+	}
+	return tag + tag_offset;
+}
+
+void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
+		    unsigned int tag)
+{
+	if (!blk_mq_tag_is_reserved(tags, tag)) {
+		const int real_tag = tag - tags->nr_reserved_tags;
+
+		BUG_ON(real_tag >= tags->nr_tags);
+		sbitmap_queue_clear(&tags->bitmap_tags, real_tag, ctx->cpu);
+	} else {
+		sbitmap_queue_clear(&tags->breserved_tags, tag, ctx->cpu);
+	}
+}
+
+void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags)
+{
+	sbitmap_queue_clear_batch(&tags->bitmap_tags, tags->nr_reserved_tags,
+					tag_array, nr_tags);
+}
+
+struct bt_iter_data {
+	struct blk_mq_hw_ctx *hctx;
+	struct request_queue *q;
+	busy_tag_iter_fn *fn;
+	void *data;
+	bool reserved;
+};
+
+static struct request *blk_mq_find_and_get_req(struct blk_mq_tags *tags,
+		unsigned int bitnr)
+{
+	struct request *rq;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tags->lock, flags);
+	rq = tags->rqs[bitnr];
+	if (!rq || rq->tag != bitnr || !req_ref_inc_not_zero(rq))
+		rq = NULL;
+	spin_unlock_irqrestore(&tags->lock, flags);
+	return rq;
+}
+
+static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
+{
+	struct bt_iter_data *iter_data = data;
+	struct blk_mq_hw_ctx *hctx = iter_data->hctx;
+	struct request_queue *q = iter_data->q;
+	struct blk_mq_tag_set *set = q->tag_set;
+	struct blk_mq_tags *tags;
+	struct request *rq;
+	bool ret = true;
+
+	if (blk_mq_is_shared_tags(set->flags))
+		tags = set->shared_tags;
+	else
+		tags = hctx->tags;
+
+	if (!iter_data->reserved)
+		bitnr += tags->nr_reserved_tags;
+	/*
+	 * We can hit rq == NULL here, because the tagging functions
+	 * test and set the bit before assigning ->rqs[].
+	 */
+	rq = blk_mq_find_and_get_req(tags, bitnr);
+	if (!rq)
+		return true;
+
+	if (rq->q == q && (!hctx || rq->mq_hctx == hctx))
+		ret = iter_data->fn(rq, iter_data->data);
+	blk_mq_put_rq_ref(rq);
+	return ret;
+}
+
+/**
+ * bt_for_each - iterate over the requests associated with a hardware queue
+ * @hctx:	Hardware queue to examine.
+ * @q:		Request queue to examine.
+ * @bt:		sbitmap to examine. This is either the breserved_tags member
+ *		or the bitmap_tags member of struct blk_mq_tags.
+ * @fn:		Pointer to the function that will be called for each request
+ *		associated with @hctx that has been assigned a driver tag.
+ *		@fn will be called as follows: @fn(@hctx, rq, @data, @reserved)
+ *		where rq is a pointer to a request. Return true to continue
+ *		iterating tags, false to stop.
+ * @data:	Will be passed as third argument to @fn.
+ * @reserved:	Indicates whether @bt is the breserved_tags member or the
+ *		bitmap_tags member of struct blk_mq_tags.
+ */
+static void bt_for_each(struct blk_mq_hw_ctx *hctx, struct request_queue *q,
+			struct sbitmap_queue *bt, busy_tag_iter_fn *fn,
+			void *data, bool reserved)
+{
+	struct bt_iter_data iter_data = {
+		.hctx = hctx,
+		.fn = fn,
+		.data = data,
+		.reserved = reserved,
+		.q = q,
+	};
+
+	sbitmap_for_each_set(&bt->sb, bt_iter, &iter_data);
+}
+
+struct bt_tags_iter_data {
+	struct blk_mq_tags *tags;
+	busy_tag_iter_fn *fn;
+	void *data;
+	unsigned int flags;
+};
+
+#define BT_TAG_ITER_RESERVED		(1 << 0)
+#define BT_TAG_ITER_STARTED		(1 << 1)
+#define BT_TAG_ITER_STATIC_RQS		(1 << 2)
+
+static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
+{
+	struct bt_tags_iter_data *iter_data = data;
+	struct blk_mq_tags *tags = iter_data->tags;
+	struct request *rq;
+	bool ret = true;
+	bool iter_static_rqs = !!(iter_data->flags & BT_TAG_ITER_STATIC_RQS);
+
+	if (!(iter_data->flags & BT_TAG_ITER_RESERVED))
+		bitnr += tags->nr_reserved_tags;
+
+	/*
+	 * We can hit rq == NULL here, because the tagging functions
+	 * test and set the bit before assigning ->rqs[].
+	 */
+	if (iter_static_rqs)
+		rq = tags->static_rqs[bitnr];
+	else
+		rq = blk_mq_find_and_get_req(tags, bitnr);
+	if (!rq)
+		return true;
+
+	if (!(iter_data->flags & BT_TAG_ITER_STARTED) ||
+	    blk_mq_request_started(rq))
+		ret = iter_data->fn(rq, iter_data->data);
+	if (!iter_static_rqs)
+		blk_mq_put_rq_ref(rq);
+	return ret;
+}
+
+/**
+ * bt_tags_for_each - iterate over the requests in a tag map
+ * @tags:	Tag map to iterate over.
+ * @bt:		sbitmap to examine. This is either the breserved_tags member
+ *		or the bitmap_tags member of struct blk_mq_tags.
+ * @fn:		Pointer to the function that will be called for each started
+ *		request. @fn will be called as follows: @fn(rq, @data,
+ *		@reserved) where rq is a pointer to a request. Return true
+ *		to continue iterating tags, false to stop.
+ * @data:	Will be passed as second argument to @fn.
+ * @flags:	BT_TAG_ITER_*
+ */
+static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt,
+			     busy_tag_iter_fn *fn, void *data, unsigned int flags)
+{
+	struct bt_tags_iter_data iter_data = {
+		.tags = tags,
+		.fn = fn,
+		.data = data,
+		.flags = flags,
+	};
+
+	if (tags->rqs)
+		sbitmap_for_each_set(&bt->sb, bt_tags_iter, &iter_data);
+}
+
+static void __blk_mq_all_tag_iter(struct blk_mq_tags *tags,
+		busy_tag_iter_fn *fn, void *priv, unsigned int flags)
+{
+	WARN_ON_ONCE(flags & BT_TAG_ITER_RESERVED);
+
+	if (tags->nr_reserved_tags)
+		bt_tags_for_each(tags, &tags->breserved_tags, fn, priv,
+				 flags | BT_TAG_ITER_RESERVED);
+	bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, flags);
+}
+
+/**
+ * blk_mq_all_tag_iter - iterate over all requests in a tag map
+ * @tags:	Tag map to iterate over.
+ * @fn:		Pointer to the function that will be called for each
+ *		request. @fn will be called as follows: @fn(rq, @priv,
+ *		reserved) where rq is a pointer to a request. 'reserved'
+ *		indicates whether or not @rq is a reserved request. Return
+ *		true to continue iterating tags, false to stop.
+ * @priv:	Will be passed as second argument to @fn.
+ *
+ * Caller has to pass the tag map from which requests are allocated.
+ */
+void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn,
+		void *priv)
+{
+	__blk_mq_all_tag_iter(tags, fn, priv, BT_TAG_ITER_STATIC_RQS);
+}
+
+/**
+ * blk_mq_tagset_busy_iter - iterate over all started requests in a tag set
+ * @tagset:	Tag set to iterate over.
+ * @fn:		Pointer to the function that will be called for each started
+ *		request. @fn will be called as follows: @fn(rq, @priv,
+ *		reserved) where rq is a pointer to a request. 'reserved'
+ *		indicates whether or not @rq is a reserved request. Return
+ *		true to continue iterating tags, false to stop.
+ * @priv:	Will be passed as second argument to @fn.
+ *
+ * We grab one request reference before calling @fn and release it after
+ * @fn returns.
+ */
+void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
+		busy_tag_iter_fn *fn, void *priv)
+{
+	unsigned int flags = tagset->flags;
+	int i, nr_tags;
+
+	nr_tags = blk_mq_is_shared_tags(flags) ? 1 : tagset->nr_hw_queues;
+
+	for (i = 0; i < nr_tags; i++) {
+		if (tagset->tags && tagset->tags[i])
+			__blk_mq_all_tag_iter(tagset->tags[i], fn, priv,
+					      BT_TAG_ITER_STARTED);
+	}
+}
+EXPORT_SYMBOL(blk_mq_tagset_busy_iter);
+
+static bool blk_mq_tagset_count_completed_rqs(struct request *rq, void *data)
+{
+	unsigned *count = data;
+
+	if (blk_mq_request_completed(rq))
+		(*count)++;
+	return true;
+}
+
+/**
+ * blk_mq_tagset_wait_completed_request - Wait until all scheduled request
+ * completions have finished.
+ * @tagset:	Tag set to drain completed request
+ *
+ * Note: This function has to be run after all IO queues are shutdown
+ */
+void blk_mq_tagset_wait_completed_request(struct blk_mq_tag_set *tagset)
+{
+	while (true) {
+		unsigned count = 0;
+
+		blk_mq_tagset_busy_iter(tagset,
+				blk_mq_tagset_count_completed_rqs, &count);
+		if (!count)
+			break;
+		msleep(5);
+	}
+}
+EXPORT_SYMBOL(blk_mq_tagset_wait_completed_request);
+
+/**
+ * blk_mq_queue_tag_busy_iter - iterate over all requests with a driver tag
+ * @q:		Request queue to examine.
+ * @fn:		Pointer to the function that will be called for each request
+ *		on @q. @fn will be called as follows: @fn(hctx, rq, @priv,
+ *		reserved) where rq is a pointer to a request and hctx points
+ *		to the hardware queue associated with the request. 'reserved'
+ *		indicates whether or not @rq is a reserved request.
+ * @priv:	Will be passed as third argument to @fn.
+ *
+ * Note: if @q->tag_set is shared with other request queues then @fn will be
+ * called for all requests on all queues that share that tag set and not only
+ * for requests associated with @q.
+ */
+void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_tag_iter_fn *fn,
+		void *priv)
+{
+	/*
+	 * __blk_mq_update_nr_hw_queues() updates nr_hw_queues and hctx_table
+	 * while the queue is frozen. So we can use q_usage_counter to avoid
+	 * racing with it.
+	 */
+	if (!percpu_ref_tryget(&q->q_usage_counter))
+		return;
+
+	if (blk_mq_is_shared_tags(q->tag_set->flags)) {
+		struct blk_mq_tags *tags = q->tag_set->shared_tags;
+		struct sbitmap_queue *bresv = &tags->breserved_tags;
+		struct sbitmap_queue *btags = &tags->bitmap_tags;
+
+		if (tags->nr_reserved_tags)
+			bt_for_each(NULL, q, bresv, fn, priv, true);
+		bt_for_each(NULL, q, btags, fn, priv, false);
+	} else {
+		struct blk_mq_hw_ctx *hctx;
+		unsigned long i;
+
+		queue_for_each_hw_ctx(q, hctx, i) {
+			struct blk_mq_tags *tags = hctx->tags;
+			struct sbitmap_queue *bresv = &tags->breserved_tags;
+			struct sbitmap_queue *btags = &tags->bitmap_tags;
+
+			/*
+			 * If no software queues are currently mapped to this
+			 * hardware queue, there's nothing to check
+			 */
+			if (!blk_mq_hw_queue_mapped(hctx))
+				continue;
+
+			if (tags->nr_reserved_tags)
+				bt_for_each(hctx, q, bresv, fn, priv, true);
+			bt_for_each(hctx, q, btags, fn, priv, false);
+		}
+	}
+	blk_queue_exit(q);
+}
+
+static int bt_alloc(struct sbitmap_queue *bt, unsigned int depth,
+		    bool round_robin, int node)
+{
+	return sbitmap_queue_init_node(bt, depth, -1, round_robin, GFP_KERNEL,
+				       node);
+}
+
+int blk_mq_init_bitmaps(struct sbitmap_queue *bitmap_tags,
+			struct sbitmap_queue *breserved_tags,
+			unsigned int queue_depth, unsigned int reserved,
+			int node, int alloc_policy)
+{
+	unsigned int depth = queue_depth - reserved;
+	bool round_robin = alloc_policy == BLK_TAG_ALLOC_RR;
+
+	if (bt_alloc(bitmap_tags, depth, round_robin, node))
+		return -ENOMEM;
+	if (bt_alloc(breserved_tags, reserved, round_robin, node))
+		goto free_bitmap_tags;
+
+	return 0;
+
+free_bitmap_tags:
+	sbitmap_queue_free(bitmap_tags);
+	return -ENOMEM;
+}
+
+struct blk_mq_tags *blk_mq_init_tags(unsigned int total_tags,
+				     unsigned int reserved_tags,
+				     int node, int alloc_policy)
+{
+	struct blk_mq_tags *tags;
+
+	if (total_tags > BLK_MQ_TAG_MAX) {
+		pr_err("blk-mq: tag depth too large\n");
+		return NULL;
+	}
+
+	tags = kzalloc_node(sizeof(*tags), GFP_KERNEL, node);
+	if (!tags)
+		return NULL;
+
+	tags->nr_tags = total_tags;
+	tags->nr_reserved_tags = reserved_tags;
+	spin_lock_init(&tags->lock);
+
+	if (blk_mq_init_bitmaps(&tags->bitmap_tags, &tags->breserved_tags,
+				total_tags, reserved_tags, node,
+				alloc_policy) < 0) {
+		kfree(tags);
+		return NULL;
+	}
+	return tags;
+}
+
+void blk_mq_free_tags(struct blk_mq_tags *tags)
+{
+	sbitmap_queue_free(&tags->bitmap_tags);
+	sbitmap_queue_free(&tags->breserved_tags);
+	kfree(tags);
+}
+
+int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
+			    struct blk_mq_tags **tagsptr, unsigned int tdepth,
+			    bool can_grow)
+{
+	struct blk_mq_tags *tags = *tagsptr;
+
+	if (tdepth <= tags->nr_reserved_tags)
+		return -EINVAL;
+
+	/*
+	 * If we are allowed to grow beyond the original size, allocate
+	 * a new set of tags before freeing the old one.
+	 */
+	if (tdepth > tags->nr_tags) {
+		struct blk_mq_tag_set *set = hctx->queue->tag_set;
+		struct blk_mq_tags *new;
+
+		if (!can_grow)
+			return -EINVAL;
+
+		/*
+		 * We need some sort of upper limit, set it high enough that
+		 * no valid use cases should require more.
+		 */
+		if (tdepth > MAX_SCHED_RQ)
+			return -EINVAL;
+
+		/*
+		 * Only the sbitmap needs resizing since we allocated the max
+		 * initially.
+		 */
+		if (blk_mq_is_shared_tags(set->flags))
+			return 0;
+
+		new = blk_mq_alloc_map_and_rqs(set, hctx->queue_num, tdepth);
+		if (!new)
+			return -ENOMEM;
+
+		blk_mq_free_map_and_rqs(set, *tagsptr, hctx->queue_num);
+		*tagsptr = new;
+	} else {
+		/*
+		 * Don't need (or can't) update reserved tags here, they
+		 * remain static and should never need resizing.
+		 */
+		sbitmap_queue_resize(&tags->bitmap_tags,
+				tdepth - tags->nr_reserved_tags);
+	}
+
+	return 0;
+}
+
+void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set, unsigned int size)
+{
+	struct blk_mq_tags *tags = set->shared_tags;
+
+	sbitmap_queue_resize(&tags->bitmap_tags, size - set->reserved_tags);
+}
+
+void blk_mq_tag_update_sched_shared_tags(struct request_queue *q)
+{
+	sbitmap_queue_resize(&q->sched_shared_tags->bitmap_tags,
+			     q->nr_requests - q->tag_set->reserved_tags);
+}
+
+/**
+ * blk_mq_unique_tag() - return a tag that is unique queue-wide
+ * @rq: request for which to compute a unique tag
+ *
+ * The tag field in struct request is unique per hardware queue but not over
+ * all hardware queues. Hence this function that returns a tag with the
+ * hardware context index in the upper bits and the per hardware queue tag in
+ * the lower bits.
+ *
+ * Note: When called for a request that is queued on a non-multiqueue request
+ * queue, the hardware context index is set to zero.
+ */
+u32 blk_mq_unique_tag(struct request *rq)
+{
+	return (rq->mq_hctx->queue_num << BLK_MQ_UNIQUE_TAG_BITS) |
+		(rq->tag & BLK_MQ_UNIQUE_TAG_MASK);
+}
+EXPORT_SYMBOL(blk_mq_unique_tag);