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, 688 insertions, 0 deletions

diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
new file mode 100644
index 000000000..f2d24b2d9
--- /dev/null
+++ b/drivers/nvme/target/loop.c
@@ -0,0 +1,688 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NVMe over Fabrics loopback device.
+ * Copyright (c) 2015-2016 HGST, a Western Digital Company.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/scatterlist.h>
+#include <linux/blk-mq.h>
+#include <linux/nvme.h>
+#include <linux/module.h>
+#include <linux/parser.h>
+#include "nvmet.h"
+#include "../host/nvme.h"
+#include "../host/fabrics.h"
+
+#define NVME_LOOP_MAX_SEGMENTS		256
+
+struct nvme_loop_iod {
+	struct nvme_request	nvme_req;
+	struct nvme_command	cmd;
+	struct nvme_completion	cqe;
+	struct nvmet_req	req;
+	struct nvme_loop_queue	*queue;
+	struct work_struct	work;
+	struct sg_table		sg_table;
+	struct scatterlist	first_sgl[];
+};
+
+struct nvme_loop_ctrl {
+	struct nvme_loop_queue	*queues;
+
+	struct blk_mq_tag_set	admin_tag_set;
+
+	struct list_head	list;
+	struct blk_mq_tag_set	tag_set;
+	struct nvme_loop_iod	async_event_iod;
+	struct nvme_ctrl	ctrl;
+
+	struct nvmet_port	*port;
+};
+
+static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl)
+{
+	return container_of(ctrl, struct nvme_loop_ctrl, ctrl);
+}
+
+enum nvme_loop_queue_flags {
+	NVME_LOOP_Q_LIVE	= 0,
+};
+
+struct nvme_loop_queue {
+	struct nvmet_cq		nvme_cq;
+	struct nvmet_sq		nvme_sq;
+	struct nvme_loop_ctrl	*ctrl;
+	unsigned long		flags;
+};
+
+static LIST_HEAD(nvme_loop_ports);
+static DEFINE_MUTEX(nvme_loop_ports_mutex);
+
+static LIST_HEAD(nvme_loop_ctrl_list);
+static DEFINE_MUTEX(nvme_loop_ctrl_mutex);
+
+static void nvme_loop_queue_response(struct nvmet_req *nvme_req);
+static void nvme_loop_delete_ctrl(struct nvmet_ctrl *ctrl);
+
+static const struct nvmet_fabrics_ops nvme_loop_ops;
+
+static inline int nvme_loop_queue_idx(struct nvme_loop_queue *queue)
+{
+	return queue - queue->ctrl->queues;
+}
+
+static void nvme_loop_complete_rq(struct request *req)
+{
+	struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
+
+	sg_free_table_chained(&iod->sg_table, NVME_INLINE_SG_CNT);
+	nvme_complete_rq(req);
+}
+
+static struct blk_mq_tags *nvme_loop_tagset(struct nvme_loop_queue *queue)
+{
+	u32 queue_idx = nvme_loop_queue_idx(queue);
+
+	if (queue_idx == 0)
+		return queue->ctrl->admin_tag_set.tags[queue_idx];
+	return queue->ctrl->tag_set.tags[queue_idx - 1];
+}
+
+static void nvme_loop_queue_response(struct nvmet_req *req)
+{
+	struct nvme_loop_queue *queue =
+		container_of(req->sq, struct nvme_loop_queue, nvme_sq);
+	struct nvme_completion *cqe = req->cqe;
+
+	/*
+	 * AEN requests are special as they don't time out and can
+	 * survive any kind of queue freeze and often don't respond to
+	 * aborts.  We don't even bother to allocate a struct request
+	 * for them but rather special case them here.
+	 */
+	if (unlikely(nvme_is_aen_req(nvme_loop_queue_idx(queue),
+				     cqe->command_id))) {
+		nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status,
+				&cqe->result);
+	} else {
+		struct request *rq;
+
+		rq = nvme_find_rq(nvme_loop_tagset(queue), cqe->command_id);
+		if (!rq) {
+			dev_err(queue->ctrl->ctrl.device,
+				"got bad command_id %#x on queue %d\n",
+				cqe->command_id, nvme_loop_queue_idx(queue));
+			return;
+		}
+
+		if (!nvme_try_complete_req(rq, cqe->status, cqe->result))
+			nvme_loop_complete_rq(rq);
+	}
+}
+
+static void nvme_loop_execute_work(struct work_struct *work)
+{
+	struct nvme_loop_iod *iod =
+		container_of(work, struct nvme_loop_iod, work);
+
+	iod->req.execute(&iod->req);
+}
+
+static blk_status_t nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx,
+		const struct blk_mq_queue_data *bd)
+{
+	struct nvme_ns *ns = hctx->queue->queuedata;
+	struct nvme_loop_queue *queue = hctx->driver_data;
+	struct request *req = bd->rq;
+	struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
+	bool queue_ready = test_bit(NVME_LOOP_Q_LIVE, &queue->flags);
+	blk_status_t ret;
+
+	if (!nvme_check_ready(&queue->ctrl->ctrl, req, queue_ready))
+		return nvme_fail_nonready_command(&queue->ctrl->ctrl, req);
+
+	ret = nvme_setup_cmd(ns, req);
+	if (ret)
+		return ret;
+
+	nvme_start_request(req);
+	iod->cmd.common.flags |= NVME_CMD_SGL_METABUF;
+	iod->req.port = queue->ctrl->port;
+	if (!nvmet_req_init(&iod->req, &queue->nvme_cq,
+			&queue->nvme_sq, &nvme_loop_ops))
+		return BLK_STS_OK;
+
+	if (blk_rq_nr_phys_segments(req)) {
+		iod->sg_table.sgl = iod->first_sgl;
+		if (sg_alloc_table_chained(&iod->sg_table,
+				blk_rq_nr_phys_segments(req),
+				iod->sg_table.sgl, NVME_INLINE_SG_CNT)) {
+			nvme_cleanup_cmd(req);
+			return BLK_STS_RESOURCE;
+		}
+
+		iod->req.sg = iod->sg_table.sgl;
+		iod->req.sg_cnt = blk_rq_map_sg(req->q, req, iod->sg_table.sgl);
+		iod->req.transfer_len = blk_rq_payload_bytes(req);
+	}
+
+	queue_work(nvmet_wq, &iod->work);
+	return BLK_STS_OK;
+}
+
+static void nvme_loop_submit_async_event(struct nvme_ctrl *arg)
+{
+	struct nvme_loop_ctrl *ctrl = to_loop_ctrl(arg);
+	struct nvme_loop_queue *queue = &ctrl->queues[0];
+	struct nvme_loop_iod *iod = &ctrl->async_event_iod;
+
+	memset(&iod->cmd, 0, sizeof(iod->cmd));
+	iod->cmd.common.opcode = nvme_admin_async_event;
+	iod->cmd.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
+	iod->cmd.common.flags |= NVME_CMD_SGL_METABUF;
+
+	if (!nvmet_req_init(&iod->req, &queue->nvme_cq, &queue->nvme_sq,
+			&nvme_loop_ops)) {
+		dev_err(ctrl->ctrl.device, "failed async event work\n");
+		return;
+	}
+
+	queue_work(nvmet_wq, &iod->work);
+}
+
+static int nvme_loop_init_iod(struct nvme_loop_ctrl *ctrl,
+		struct nvme_loop_iod *iod, unsigned int queue_idx)
+{
+	iod->req.cmd = &iod->cmd;
+	iod->req.cqe = &iod->cqe;
+	iod->queue = &ctrl->queues[queue_idx];
+	INIT_WORK(&iod->work, nvme_loop_execute_work);
+	return 0;
+}
+
+static int nvme_loop_init_request(struct blk_mq_tag_set *set,
+		struct request *req, unsigned int hctx_idx,
+		unsigned int numa_node)
+{
+	struct nvme_loop_ctrl *ctrl = to_loop_ctrl(set->driver_data);
+	struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req);
+
+	nvme_req(req)->ctrl = &ctrl->ctrl;
+	nvme_req(req)->cmd = &iod->cmd;
+	return nvme_loop_init_iod(ctrl, blk_mq_rq_to_pdu(req),
+			(set == &ctrl->tag_set) ? hctx_idx + 1 : 0);
+}
+
+static struct lock_class_key loop_hctx_fq_lock_key;
+
+static int nvme_loop_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	struct nvme_loop_ctrl *ctrl = to_loop_ctrl(data);
+	struct nvme_loop_queue *queue = &ctrl->queues[hctx_idx + 1];
+
+	BUG_ON(hctx_idx >= ctrl->ctrl.queue_count);
+
+	/*
+	 * flush_end_io() can be called recursively for us, so use our own
+	 * lock class key for avoiding lockdep possible recursive locking,
+	 * then we can remove the dynamically allocated lock class for each
+	 * flush queue, that way may cause horrible boot delay.
+	 */
+	blk_mq_hctx_set_fq_lock_class(hctx, &loop_hctx_fq_lock_key);
+
+	hctx->driver_data = queue;
+	return 0;
+}
+
+static int nvme_loop_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
+		unsigned int hctx_idx)
+{
+	struct nvme_loop_ctrl *ctrl = to_loop_ctrl(data);
+	struct nvme_loop_queue *queue = &ctrl->queues[0];
+
+	BUG_ON(hctx_idx != 0);
+
+	hctx->driver_data = queue;
+	return 0;
+}
+
+static const struct blk_mq_ops nvme_loop_mq_ops = {
+	.queue_rq	= nvme_loop_queue_rq,
+	.complete	= nvme_loop_complete_rq,
+	.init_request	= nvme_loop_init_request,
+	.init_hctx	= nvme_loop_init_hctx,
+};
+
+static const struct blk_mq_ops nvme_loop_admin_mq_ops = {
+	.queue_rq	= nvme_loop_queue_rq,
+	.complete	= nvme_loop_complete_rq,
+	.init_request	= nvme_loop_init_request,
+	.init_hctx	= nvme_loop_init_admin_hctx,
+};
+
+static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl)
+{
+	if (!test_and_clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags))
+		return;
+	nvmet_sq_destroy(&ctrl->queues[0].nvme_sq);
+	nvme_remove_admin_tag_set(&ctrl->ctrl);
+}
+
+static void nvme_loop_free_ctrl(struct nvme_ctrl *nctrl)
+{
+	struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl);
+
+	if (list_empty(&ctrl->list))
+		goto free_ctrl;
+
+	mutex_lock(&nvme_loop_ctrl_mutex);
+	list_del(&ctrl->list);
+	mutex_unlock(&nvme_loop_ctrl_mutex);
+
+	if (nctrl->tagset)
+		nvme_remove_io_tag_set(nctrl);
+	kfree(ctrl->queues);
+	nvmf_free_options(nctrl->opts);
+free_ctrl:
+	kfree(ctrl);
+}
+
+static void nvme_loop_destroy_io_queues(struct nvme_loop_ctrl *ctrl)
+{
+	int i;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
+		clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags);
+		nvmet_sq_destroy(&ctrl->queues[i].nvme_sq);
+	}
+	ctrl->ctrl.queue_count = 1;
+}
+
+static int nvme_loop_init_io_queues(struct nvme_loop_ctrl *ctrl)
+{
+	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
+	unsigned int nr_io_queues;
+	int ret, i;
+
+	nr_io_queues = min(opts->nr_io_queues, num_online_cpus());
+	ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
+	if (ret || !nr_io_queues)
+		return ret;
+
+	dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n", nr_io_queues);
+
+	for (i = 1; i <= nr_io_queues; i++) {
+		ctrl->queues[i].ctrl = ctrl;
+		ret = nvmet_sq_init(&ctrl->queues[i].nvme_sq);
+		if (ret)
+			goto out_destroy_queues;
+
+		ctrl->ctrl.queue_count++;
+	}
+
+	return 0;
+
+out_destroy_queues:
+	nvme_loop_destroy_io_queues(ctrl);
+	return ret;
+}
+
+static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl)
+{
+	int i, ret;
+
+	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
+		ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
+		if (ret)
+			return ret;
+		set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags);
+	}
+
+	return 0;
+}
+
+static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl)
+{
+	int error;
+
+	ctrl->queues[0].ctrl = ctrl;
+	error = nvmet_sq_init(&ctrl->queues[0].nvme_sq);
+	if (error)
+		return error;
+	ctrl->ctrl.queue_count = 1;
+
+	error = nvme_alloc_admin_tag_set(&ctrl->ctrl, &ctrl->admin_tag_set,
+			&nvme_loop_admin_mq_ops,
+			sizeof(struct nvme_loop_iod) +
+			NVME_INLINE_SG_CNT * sizeof(struct scatterlist));
+	if (error)
+		goto out_free_sq;
+
+	/* reset stopped state for the fresh admin queue */
+	clear_bit(NVME_CTRL_ADMIN_Q_STOPPED, &ctrl->ctrl.flags);
+
+	error = nvmf_connect_admin_queue(&ctrl->ctrl);
+	if (error)
+		goto out_cleanup_tagset;
+
+	set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags);
+
+	error = nvme_enable_ctrl(&ctrl->ctrl);
+	if (error)
+		goto out_cleanup_tagset;
+
+	ctrl->ctrl.max_hw_sectors =
+		(NVME_LOOP_MAX_SEGMENTS - 1) << (PAGE_SHIFT - 9);
+
+	nvme_unquiesce_admin_queue(&ctrl->ctrl);
+
+	error = nvme_init_ctrl_finish(&ctrl->ctrl, false);
+	if (error)
+		goto out_cleanup_tagset;
+
+	return 0;
+
+out_cleanup_tagset:
+	clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags);
+	nvme_remove_admin_tag_set(&ctrl->ctrl);
+out_free_sq:
+	nvmet_sq_destroy(&ctrl->queues[0].nvme_sq);
+	return error;
+}
+
+static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl)
+{
+	if (ctrl->ctrl.queue_count > 1) {
+		nvme_quiesce_io_queues(&ctrl->ctrl);
+		nvme_cancel_tagset(&ctrl->ctrl);
+		nvme_loop_destroy_io_queues(ctrl);
+	}
+
+	nvme_quiesce_admin_queue(&ctrl->ctrl);
+	if (ctrl->ctrl.state == NVME_CTRL_LIVE)
+		nvme_disable_ctrl(&ctrl->ctrl, true);
+
+	nvme_cancel_admin_tagset(&ctrl->ctrl);
+	nvme_loop_destroy_admin_queue(ctrl);
+}
+
+static void nvme_loop_delete_ctrl_host(struct nvme_ctrl *ctrl)
+{
+	nvme_loop_shutdown_ctrl(to_loop_ctrl(ctrl));
+}
+
+static void nvme_loop_delete_ctrl(struct nvmet_ctrl *nctrl)
+{
+	struct nvme_loop_ctrl *ctrl;
+
+	mutex_lock(&nvme_loop_ctrl_mutex);
+	list_for_each_entry(ctrl, &nvme_loop_ctrl_list, list) {
+		if (ctrl->ctrl.cntlid == nctrl->cntlid)
+			nvme_delete_ctrl(&ctrl->ctrl);
+	}
+	mutex_unlock(&nvme_loop_ctrl_mutex);
+}
+
+static void nvme_loop_reset_ctrl_work(struct work_struct *work)
+{
+	struct nvme_loop_ctrl *ctrl =
+		container_of(work, struct nvme_loop_ctrl, ctrl.reset_work);
+	int ret;
+
+	nvme_stop_ctrl(&ctrl->ctrl);
+	nvme_loop_shutdown_ctrl(ctrl);
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
+		if (ctrl->ctrl.state != NVME_CTRL_DELETING &&
+		    ctrl->ctrl.state != NVME_CTRL_DELETING_NOIO)
+			/* state change failure for non-deleted ctrl? */
+			WARN_ON_ONCE(1);
+		return;
+	}
+
+	ret = nvme_loop_configure_admin_queue(ctrl);
+	if (ret)
+		goto out_disable;
+
+	ret = nvme_loop_init_io_queues(ctrl);
+	if (ret)
+		goto out_destroy_admin;
+
+	ret = nvme_loop_connect_io_queues(ctrl);
+	if (ret)
+		goto out_destroy_io;
+
+	blk_mq_update_nr_hw_queues(&ctrl->tag_set,
+			ctrl->ctrl.queue_count - 1);
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE))
+		WARN_ON_ONCE(1);
+
+	nvme_start_ctrl(&ctrl->ctrl);
+
+	return;
+
+out_destroy_io:
+	nvme_loop_destroy_io_queues(ctrl);
+out_destroy_admin:
+	nvme_loop_destroy_admin_queue(ctrl);
+out_disable:
+	dev_warn(ctrl->ctrl.device, "Removing after reset failure\n");
+	nvme_uninit_ctrl(&ctrl->ctrl);
+}
+
+static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = {
+	.name			= "loop",
+	.module			= THIS_MODULE,
+	.flags			= NVME_F_FABRICS,
+	.reg_read32		= nvmf_reg_read32,
+	.reg_read64		= nvmf_reg_read64,
+	.reg_write32		= nvmf_reg_write32,
+	.free_ctrl		= nvme_loop_free_ctrl,
+	.submit_async_event	= nvme_loop_submit_async_event,
+	.delete_ctrl		= nvme_loop_delete_ctrl_host,
+	.get_address		= nvmf_get_address,
+};
+
+static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl)
+{
+	int ret;
+
+	ret = nvme_loop_init_io_queues(ctrl);
+	if (ret)
+		return ret;
+
+	ret = nvme_alloc_io_tag_set(&ctrl->ctrl, &ctrl->tag_set,
+			&nvme_loop_mq_ops, 1,
+			sizeof(struct nvme_loop_iod) +
+			NVME_INLINE_SG_CNT * sizeof(struct scatterlist));
+	if (ret)
+		goto out_destroy_queues;
+
+	ret = nvme_loop_connect_io_queues(ctrl);
+	if (ret)
+		goto out_cleanup_tagset;
+
+	return 0;
+
+out_cleanup_tagset:
+	nvme_remove_io_tag_set(&ctrl->ctrl);
+out_destroy_queues:
+	nvme_loop_destroy_io_queues(ctrl);
+	return ret;
+}
+
+static struct nvmet_port *nvme_loop_find_port(struct nvme_ctrl *ctrl)
+{
+	struct nvmet_port *p, *found = NULL;
+
+	mutex_lock(&nvme_loop_ports_mutex);
+	list_for_each_entry(p, &nvme_loop_ports, entry) {
+		/* if no transport address is specified use the first port */
+		if ((ctrl->opts->mask & NVMF_OPT_TRADDR) &&
+		    strcmp(ctrl->opts->traddr, p->disc_addr.traddr))
+			continue;
+		found = p;
+		break;
+	}
+	mutex_unlock(&nvme_loop_ports_mutex);
+	return found;
+}
+
+static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev,
+		struct nvmf_ctrl_options *opts)
+{
+	struct nvme_loop_ctrl *ctrl;
+	int ret;
+
+	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
+	if (!ctrl)
+		return ERR_PTR(-ENOMEM);
+	ctrl->ctrl.opts = opts;
+	INIT_LIST_HEAD(&ctrl->list);
+
+	INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work);
+
+	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops,
+				0 /* no quirks, we're perfect! */);
+	if (ret) {
+		kfree(ctrl);
+		goto out;
+	}
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
+		WARN_ON_ONCE(1);
+
+	ret = -ENOMEM;
+
+	ctrl->ctrl.kato = opts->kato;
+	ctrl->port = nvme_loop_find_port(&ctrl->ctrl);
+
+	ctrl->queues = kcalloc(opts->nr_io_queues + 1, sizeof(*ctrl->queues),
+			GFP_KERNEL);
+	if (!ctrl->queues)
+		goto out_uninit_ctrl;
+
+	ret = nvme_loop_configure_admin_queue(ctrl);
+	if (ret)
+		goto out_free_queues;
+
+	if (opts->queue_size > ctrl->ctrl.maxcmd) {
+		/* warn if maxcmd is lower than queue_size */
+		dev_warn(ctrl->ctrl.device,
+			"queue_size %zu > ctrl maxcmd %u, clamping down\n",
+			opts->queue_size, ctrl->ctrl.maxcmd);
+		opts->queue_size = ctrl->ctrl.maxcmd;
+	}
+	ctrl->ctrl.sqsize = opts->queue_size - 1;
+
+	if (opts->nr_io_queues) {
+		ret = nvme_loop_create_io_queues(ctrl);
+		if (ret)
+			goto out_remove_admin_queue;
+	}
+
+	nvme_loop_init_iod(ctrl, &ctrl->async_event_iod, 0);
+
+	dev_info(ctrl->ctrl.device,
+		 "new ctrl: \"%s\"\n", ctrl->ctrl.opts->subsysnqn);
+
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE))
+		WARN_ON_ONCE(1);
+
+	mutex_lock(&nvme_loop_ctrl_mutex);
+	list_add_tail(&ctrl->list, &nvme_loop_ctrl_list);
+	mutex_unlock(&nvme_loop_ctrl_mutex);
+
+	nvme_start_ctrl(&ctrl->ctrl);
+
+	return &ctrl->ctrl;
+
+out_remove_admin_queue:
+	nvme_loop_destroy_admin_queue(ctrl);
+out_free_queues:
+	kfree(ctrl->queues);
+out_uninit_ctrl:
+	nvme_uninit_ctrl(&ctrl->ctrl);
+	nvme_put_ctrl(&ctrl->ctrl);
+out:
+	if (ret > 0)
+		ret = -EIO;
+	return ERR_PTR(ret);
+}
+
+static int nvme_loop_add_port(struct nvmet_port *port)
+{
+	mutex_lock(&nvme_loop_ports_mutex);
+	list_add_tail(&port->entry, &nvme_loop_ports);
+	mutex_unlock(&nvme_loop_ports_mutex);
+	return 0;
+}
+
+static void nvme_loop_remove_port(struct nvmet_port *port)
+{
+	mutex_lock(&nvme_loop_ports_mutex);
+	list_del_init(&port->entry);
+	mutex_unlock(&nvme_loop_ports_mutex);
+
+	/*
+	 * Ensure any ctrls that are in the process of being
+	 * deleted are in fact deleted before we return
+	 * and free the port. This is to prevent active
+	 * ctrls from using a port after it's freed.
+	 */
+	flush_workqueue(nvme_delete_wq);
+}
+
+static const struct nvmet_fabrics_ops nvme_loop_ops = {
+	.owner		= THIS_MODULE,
+	.type		= NVMF_TRTYPE_LOOP,
+	.add_port	= nvme_loop_add_port,
+	.remove_port	= nvme_loop_remove_port,
+	.queue_response = nvme_loop_queue_response,
+	.delete_ctrl	= nvme_loop_delete_ctrl,
+};
+
+static struct nvmf_transport_ops nvme_loop_transport = {
+	.name		= "loop",
+	.module		= THIS_MODULE,
+	.create_ctrl	= nvme_loop_create_ctrl,
+	.allowed_opts	= NVMF_OPT_TRADDR,
+};
+
+static int __init nvme_loop_init_module(void)
+{
+	int ret;
+
+	ret = nvmet_register_transport(&nvme_loop_ops);
+	if (ret)
+		return ret;
+
+	ret = nvmf_register_transport(&nvme_loop_transport);
+	if (ret)
+		nvmet_unregister_transport(&nvme_loop_ops);
+
+	return ret;
+}
+
+static void __exit nvme_loop_cleanup_module(void)
+{
+	struct nvme_loop_ctrl *ctrl, *next;
+
+	nvmf_unregister_transport(&nvme_loop_transport);
+	nvmet_unregister_transport(&nvme_loop_ops);
+
+	mutex_lock(&nvme_loop_ctrl_mutex);
+	list_for_each_entry_safe(ctrl, next, &nvme_loop_ctrl_list, list)
+		nvme_delete_ctrl(&ctrl->ctrl);
+	mutex_unlock(&nvme_loop_ctrl_mutex);
+
+	flush_workqueue(nvme_delete_wq);
+}
+
+module_init(nvme_loop_init_module);
+module_exit(nvme_loop_cleanup_module);
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("nvmet-transport-254"); /* 254 == NVMF_TRTYPE_LOOP */