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    SubjectRe: [PATCH 5/5] nvme-rdma: add a NVMe over Fabrics RDMA host driver
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    Date
    We forgot to CC Linux-rdma, CC'ing...

    On 07/06/16 00:23, Christoph Hellwig wrote:
    > This patch implements the RDMA host (initiator in SCSI speak) driver. It
    > can be used to connect to remote NVMe over Fabrics controllers over
    > Infiniband, RoCE or iWarp, and uses the existing NVMe core driver as well
    > a the new fabrics library.
    >
    > To connect to all NVMe over Fabrics controller reachable on a given taget
    > port using RDMA/CM use the following command:
    >
    > nvme connect-all -t rdma -a $IPADDR
    >
    > This requires the latest version of nvme-cli with Fabrics support.
    >
    > Signed-off-by: Jay Freyensee <james.p.freyensee@intel.com>
    > Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
    > Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
    > Signed-off-by: Christoph Hellwig <hch@lst.de>
    > ---
    > drivers/nvme/host/Kconfig | 16 +
    > drivers/nvme/host/Makefile | 3 +
    > drivers/nvme/host/rdma.c | 2009 ++++++++++++++++++++++++++++++++++++++++++++
    > 3 files changed, 2028 insertions(+)
    > create mode 100644 drivers/nvme/host/rdma.c
    >
    > diff --git a/drivers/nvme/host/Kconfig b/drivers/nvme/host/Kconfig
    > index 3397651..db39d53 100644
    > --- a/drivers/nvme/host/Kconfig
    > +++ b/drivers/nvme/host/Kconfig
    > @@ -27,3 +27,19 @@ config BLK_DEV_NVME_SCSI
    >
    > config NVME_FABRICS
    > tristate
    > +
    > +config NVME_RDMA
    > + tristate "NVM Express over Fabrics RDMA host driver"
    > + depends on INFINIBAND
    > + depends on BLK_DEV_NVME
    > + select NVME_FABRICS
    > + select SG_POOL
    > + help
    > + This provides support for the NVMe over Fabrics protocol using
    > + the RDMA (Infiniband, RoCE, iWarp) transport. This allows you
    > + to use remote block devices exported using the NVMe protocol set.
    > +
    > + To configure a NVMe over Fabrics controller use the nvme-cli tool
    > + from https://github.com/linux-nvme/nvme-cli.
    > +
    > + If unsure, say N.
    > diff --git a/drivers/nvme/host/Makefile b/drivers/nvme/host/Makefile
    > index 5f8648f..47abcec 100644
    > --- a/drivers/nvme/host/Makefile
    > +++ b/drivers/nvme/host/Makefile
    > @@ -1,6 +1,7 @@
    > obj-$(CONFIG_NVME_CORE) += nvme-core.o
    > obj-$(CONFIG_BLK_DEV_NVME) += nvme.o
    > obj-$(CONFIG_NVME_FABRICS) += nvme-fabrics.o
    > +obj-$(CONFIG_NVME_RDMA) += nvme-rdma.o
    >
    > nvme-core-y := core.o
    > nvme-core-$(CONFIG_BLK_DEV_NVME_SCSI) += scsi.o
    > @@ -9,3 +10,5 @@ nvme-core-$(CONFIG_NVM) += lightnvm.o
    > nvme-y += pci.o
    >
    > nvme-fabrics-y += fabrics.o
    > +
    > +nvme-rdma-y += rdma.o
    > diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
    > new file mode 100644
    > index 0000000..4edc912
    > --- /dev/null
    > +++ b/drivers/nvme/host/rdma.c
    > @@ -0,0 +1,2009 @@
    > +/*
    > + * NVMe over Fabrics RDMA host code.
    > + * Copyright (c) 2015-2016 HGST, a Western Digital Company.
    > + *
    > + * This program is free software; you can redistribute it and/or modify it
    > + * under the terms and conditions of the GNU General Public License,
    > + * version 2, as published by the Free Software Foundation.
    > + *
    > + * This program is distributed in the hope it will be useful, but WITHOUT
    > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
    > + * more details.
    > + */
    > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
    > +#include <linux/delay.h>
    > +#include <linux/module.h>
    > +#include <linux/init.h>
    > +#include <linux/slab.h>
    > +#include <linux/err.h>
    > +#include <linux/string.h>
    > +#include <linux/jiffies.h>
    > +#include <linux/atomic.h>
    > +#include <linux/blk-mq.h>
    > +#include <linux/types.h>
    > +#include <linux/list.h>
    > +#include <linux/mutex.h>
    > +#include <linux/scatterlist.h>
    > +#include <linux/nvme.h>
    > +#include <linux/t10-pi.h>
    > +#include <asm/unaligned.h>
    > +
    > +#include <rdma/ib_verbs.h>
    > +#include <rdma/rdma_cm.h>
    > +#include <rdma/ib_cm.h>
    > +#include <linux/nvme-rdma.h>
    > +
    > +#include "nvme.h"
    > +#include "fabrics.h"
    > +
    > +
    > +#define NVME_RDMA_CONNECT_TIMEOUT_MS 1000 /* 1 second */
    > +
    > +#define NVME_RDMA_MAX_SEGMENT_SIZE 0xffffff /* 24-bit SGL field */
    > +
    > +#define NVME_RDMA_MAX_SEGMENTS 256
    > +
    > +#define NVME_RDMA_MAX_INLINE_SEGMENTS 1
    > +
    > +#define NVME_RDMA_MAX_PAGES_PER_MR 512
    > +
    > +#define NVME_RDMA_DEF_RECONNECT_DELAY 20
    > +
    > +/*
    > + * We handle AEN commands ourselves and don't even let the
    > + * block layer know about them.
    > + */
    > +#define NVME_RDMA_NR_AEN_COMMANDS 1
    > +#define NVME_RDMA_AQ_BLKMQ_DEPTH \
    > + (NVMF_AQ_DEPTH - NVME_RDMA_NR_AEN_COMMANDS)
    > +
    > +struct nvme_rdma_device {
    > + struct ib_device *dev;
    > + struct ib_pd *pd;
    > + struct ib_mr *mr;
    > + struct kref ref;
    > + struct list_head entry;
    > +};
    > +
    > +struct nvme_rdma_qe {
    > + struct ib_cqe cqe;
    > + void *data;
    > + u64 dma;
    > +};
    > +
    > +struct nvme_rdma_queue;
    > +struct nvme_rdma_request {
    > + struct ib_mr *mr;
    > + struct nvme_rdma_qe sqe;
    > + struct ib_sge sge[1 + NVME_RDMA_MAX_INLINE_SEGMENTS];
    > + u32 num_sge;
    > + int nents;
    > + bool inline_data;
    > + bool need_inval;
    > + struct ib_reg_wr reg_wr;
    > + struct ib_cqe reg_cqe;
    > + struct nvme_rdma_queue *queue;
    > + struct sg_table sg_table;
    > + struct scatterlist first_sgl[];
    > +};
    > +
    > +enum nvme_rdma_queue_flags {
    > + NVME_RDMA_Q_CONNECTED = (1 << 0),
    > +};
    > +
    > +struct nvme_rdma_queue {
    > + struct nvme_rdma_qe *rsp_ring;
    > + u8 sig_count;
    > + int queue_size;
    > + size_t cmnd_capsule_len;
    > + struct nvme_rdma_ctrl *ctrl;
    > + struct nvme_rdma_device *device;
    > + struct ib_cq *ib_cq;
    > + struct ib_qp *qp;
    > +
    > + unsigned long flags;
    > + struct rdma_cm_id *cm_id;
    > + int cm_error;
    > + struct completion cm_done;
    > +};
    > +
    > +struct nvme_rdma_ctrl {
    > + /* read and written in the hot path */
    > + spinlock_t lock;
    > +
    > + /* read only in the hot path */
    > + struct nvme_rdma_queue *queues;
    > + u32 queue_count;
    > +
    > + /* other member variables */
    > + unsigned short tl_retry_count;
    > + struct blk_mq_tag_set tag_set;
    > + struct work_struct delete_work;
    > + struct work_struct reset_work;
    > + struct work_struct err_work;
    > +
    > + struct nvme_rdma_qe async_event_sqe;
    > +
    > + int reconnect_delay;
    > + struct delayed_work reconnect_work;
    > +
    > + struct list_head list;
    > +
    > + struct blk_mq_tag_set admin_tag_set;
    > + struct nvme_rdma_device *device;
    > +
    > + u64 cap;
    > + u32 max_fr_pages;
    > +
    > + union {
    > + struct sockaddr addr;
    > + struct sockaddr_in addr_in;
    > + };
    > +
    > + struct nvme_ctrl ctrl;
    > +};
    > +
    > +static inline struct nvme_rdma_ctrl *to_rdma_ctrl(struct nvme_ctrl *ctrl)
    > +{
    > + return container_of(ctrl, struct nvme_rdma_ctrl, ctrl);
    > +}
    > +
    > +static LIST_HEAD(device_list);
    > +static DEFINE_MUTEX(device_list_mutex);
    > +
    > +static LIST_HEAD(nvme_rdma_ctrl_list);
    > +static DEFINE_MUTEX(nvme_rdma_ctrl_mutex);
    > +
    > +static struct workqueue_struct *nvme_rdma_wq;
    > +
    > +/*
    > + * Disabling this option makes small I/O goes faster, but is fundamentally
    > + * unsafe. With it turned off we will have to register a global rkey that
    > + * allows read and write access to all physical memory.
    > + */
    > +static bool register_always = true;
    > +module_param(register_always, bool, 0444);
    > +MODULE_PARM_DESC(register_always,
    > + "Use memory registration even for contiguous memory regions");
    > +
    > +static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
    > + struct rdma_cm_event *event);
    > +static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
    > +static int __nvme_rdma_del_ctrl(struct nvme_rdma_ctrl *ctrl);
    > +
    > +/* XXX: really should move to a generic header sooner or later.. */
    > +static inline void put_unaligned_le24(u32 val, u8 *p)
    > +{
    > + *p++ = val;
    > + *p++ = val >> 8;
    > + *p++ = val >> 16;
    > +}
    > +
    > +static inline int nvme_rdma_queue_idx(struct nvme_rdma_queue *queue)
    > +{
    > + return queue - queue->ctrl->queues;
    > +}
    > +
    > +static inline size_t nvme_rdma_inline_data_size(struct nvme_rdma_queue *queue)
    > +{
    > + return queue->cmnd_capsule_len - sizeof(struct nvme_command);
    > +}
    > +
    > +static void nvme_rdma_free_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
    > + size_t capsule_size, enum dma_data_direction dir)
    > +{
    > + ib_dma_unmap_single(ibdev, qe->dma, capsule_size, dir);
    > + kfree(qe->data);
    > +}
    > +
    > +static int nvme_rdma_alloc_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
    > + size_t capsule_size, enum dma_data_direction dir)
    > +{
    > + qe->data = kzalloc(capsule_size, GFP_KERNEL);
    > + if (!qe->data)
    > + return -ENOMEM;
    > +
    > + qe->dma = ib_dma_map_single(ibdev, qe->data, capsule_size, dir);
    > + if (ib_dma_mapping_error(ibdev, qe->dma)) {
    > + kfree(qe->data);
    > + return -ENOMEM;
    > + }
    > +
    > + return 0;
    > +}
    > +
    > +static void nvme_rdma_free_ring(struct ib_device *ibdev,
    > + struct nvme_rdma_qe *ring, size_t ib_queue_size,
    > + size_t capsule_size, enum dma_data_direction dir)
    > +{
    > + int i;
    > +
    > + for (i = 0; i < ib_queue_size; i++)
    > + nvme_rdma_free_qe(ibdev, &ring[i], capsule_size, dir);
    > + kfree(ring);
    > +}
    > +
    > +static struct nvme_rdma_qe *nvme_rdma_alloc_ring(struct ib_device *ibdev,
    > + size_t ib_queue_size, size_t capsule_size,
    > + enum dma_data_direction dir)
    > +{
    > + struct nvme_rdma_qe *ring;
    > + int i;
    > +
    > + ring = kcalloc(ib_queue_size, sizeof(struct nvme_rdma_qe), GFP_KERNEL);
    > + if (!ring)
    > + return NULL;
    > +
    > + for (i = 0; i < ib_queue_size; i++) {
    > + if (nvme_rdma_alloc_qe(ibdev, &ring[i], capsule_size, dir))
    > + goto out_free_ring;
    > + }
    > +
    > + return ring;
    > +
    > +out_free_ring:
    > + nvme_rdma_free_ring(ibdev, ring, i, capsule_size, dir);
    > + return NULL;
    > +}
    > +
    > +static void nvme_rdma_qp_event(struct ib_event *event, void *context)
    > +{
    > + pr_debug("QP event %d\n", event->event);
    > +}
    > +
    > +static int nvme_rdma_wait_for_cm(struct nvme_rdma_queue *queue)
    > +{
    > + wait_for_completion_interruptible_timeout(&queue->cm_done,
    > + msecs_to_jiffies(NVME_RDMA_CONNECT_TIMEOUT_MS) + 1);
    > + return queue->cm_error;
    > +}
    > +
    > +static int nvme_rdma_create_qp(struct nvme_rdma_queue *queue, const int factor)
    > +{
    > + struct nvme_rdma_device *dev = queue->device;
    > + struct ib_qp_init_attr init_attr;
    > + int ret;
    > +
    > + memset(&init_attr, 0, sizeof(init_attr));
    > + init_attr.event_handler = nvme_rdma_qp_event;
    > + /* +1 for drain */
    > + init_attr.cap.max_send_wr = factor * queue->queue_size + 1;
    > + /* +1 for drain */
    > + init_attr.cap.max_recv_wr = queue->queue_size + 1;
    > + init_attr.cap.max_recv_sge = 1;
    > + init_attr.cap.max_send_sge = 1 + NVME_RDMA_MAX_INLINE_SEGMENTS;
    > + init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
    > + init_attr.qp_type = IB_QPT_RC;
    > + init_attr.send_cq = queue->ib_cq;
    > + init_attr.recv_cq = queue->ib_cq;
    > +
    > + ret = rdma_create_qp(queue->cm_id, dev->pd, &init_attr);
    > +
    > + queue->qp = queue->cm_id->qp;
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_reinit_request(void *data, struct request *rq)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = data;
    > + struct nvme_rdma_device *dev = ctrl->device;
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + int ret = 0;
    > +
    > + if (!req->need_inval)
    > + goto out;
    > +
    > + ib_dereg_mr(req->mr);
    > +
    > + req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,
    > + ctrl->max_fr_pages);
    > + if (IS_ERR(req->mr)) {
    > + req->mr = NULL;
    > + ret = PTR_ERR(req->mr);
    > + }
    > +
    > + req->need_inval = false;
    > +
    > +out:
    > + return ret;
    > +}
    > +
    > +static void __nvme_rdma_exit_request(struct nvme_rdma_ctrl *ctrl,
    > + struct request *rq, unsigned int queue_idx)
    > +{
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
    > + struct nvme_rdma_device *dev = queue->device;
    > +
    > + if (req->mr)
    > + ib_dereg_mr(req->mr);
    > +
    > + nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
    > + DMA_TO_DEVICE);
    > +}
    > +
    > +static void nvme_rdma_exit_request(void *data, struct request *rq,
    > + unsigned int hctx_idx, unsigned int rq_idx)
    > +{
    > + return __nvme_rdma_exit_request(data, rq, hctx_idx + 1);
    > +}
    > +
    > +static void nvme_rdma_exit_admin_request(void *data, struct request *rq,
    > + unsigned int hctx_idx, unsigned int rq_idx)
    > +{
    > + return __nvme_rdma_exit_request(data, rq, 0);
    > +}
    > +
    > +static int __nvme_rdma_init_request(struct nvme_rdma_ctrl *ctrl,
    > + struct request *rq, unsigned int queue_idx)
    > +{
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
    > + struct nvme_rdma_device *dev = queue->device;
    > + struct ib_device *ibdev = dev->dev;
    > + int ret;
    > +
    > + BUG_ON(queue_idx >= ctrl->queue_count);
    > +
    > + ret = nvme_rdma_alloc_qe(ibdev, &req->sqe, sizeof(struct nvme_command),
    > + DMA_TO_DEVICE);
    > + if (ret)
    > + return ret;
    > +
    > + req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,
    > + ctrl->max_fr_pages);
    > + if (IS_ERR(req->mr)) {
    > + ret = PTR_ERR(req->mr);
    > + goto out_free_qe;
    > + }
    > +
    > + req->queue = queue;
    > +
    > + return 0;
    > +
    > +out_free_qe:
    > + nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
    > + DMA_TO_DEVICE);
    > + return -ENOMEM;
    > +}
    > +
    > +static int nvme_rdma_init_request(void *data, struct request *rq,
    > + unsigned int hctx_idx, unsigned int rq_idx,
    > + unsigned int numa_node)
    > +{
    > + return __nvme_rdma_init_request(data, rq, hctx_idx + 1);
    > +}
    > +
    > +static int nvme_rdma_init_admin_request(void *data, struct request *rq,
    > + unsigned int hctx_idx, unsigned int rq_idx,
    > + unsigned int numa_node)
    > +{
    > + return __nvme_rdma_init_request(data, rq, 0);
    > +}
    > +
    > +static int nvme_rdma_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
    > + unsigned int hctx_idx)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = data;
    > + struct nvme_rdma_queue *queue = &ctrl->queues[hctx_idx + 1];
    > +
    > + BUG_ON(hctx_idx >= ctrl->queue_count);
    > +
    > + hctx->driver_data = queue;
    > + return 0;
    > +}
    > +
    > +static int nvme_rdma_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
    > + unsigned int hctx_idx)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = data;
    > + struct nvme_rdma_queue *queue = &ctrl->queues[0];
    > +
    > + BUG_ON(hctx_idx != 0);
    > +
    > + hctx->driver_data = queue;
    > + return 0;
    > +}
    > +
    > +static void nvme_rdma_free_dev(struct kref *ref)
    > +{
    > + struct nvme_rdma_device *ndev =
    > + container_of(ref, struct nvme_rdma_device, ref);
    > +
    > + mutex_lock(&device_list_mutex);
    > + list_del(&ndev->entry);
    > + mutex_unlock(&device_list_mutex);
    > +
    > + if (!register_always)
    > + ib_dereg_mr(ndev->mr);
    > + ib_dealloc_pd(ndev->pd);
    > +
    > + kfree(ndev);
    > +}
    > +
    > +static void nvme_rdma_dev_put(struct nvme_rdma_device *dev)
    > +{
    > + kref_put(&dev->ref, nvme_rdma_free_dev);
    > +}
    > +
    > +static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
    > +{
    > + return kref_get_unless_zero(&dev->ref);
    > +}
    > +
    > +static struct nvme_rdma_device *
    > +nvme_rdma_find_get_device(struct rdma_cm_id *cm_id)
    > +{
    > + struct nvme_rdma_device *ndev;
    > +
    > + mutex_lock(&device_list_mutex);
    > + list_for_each_entry(ndev, &device_list, entry) {
    > + if (ndev->dev->node_guid == cm_id->device->node_guid &&
    > + nvme_rdma_dev_get(ndev))
    > + goto out_unlock;
    > + }
    > +
    > + ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
    > + if (!ndev)
    > + goto out_err;
    > +
    > + ndev->dev = cm_id->device;
    > + kref_init(&ndev->ref);
    > +
    > + ndev->pd = ib_alloc_pd(ndev->dev);
    > + if (IS_ERR(ndev->pd))
    > + goto out_free_dev;
    > +
    > + if (!register_always) {
    > + ndev->mr = ib_get_dma_mr(ndev->pd,
    > + IB_ACCESS_LOCAL_WRITE |
    > + IB_ACCESS_REMOTE_READ |
    > + IB_ACCESS_REMOTE_WRITE);
    > + if (IS_ERR(ndev->mr))
    > + goto out_free_pd;
    > + }
    > +
    > + if (!(ndev->dev->attrs.device_cap_flags &
    > + IB_DEVICE_MEM_MGT_EXTENSIONS)) {
    > + dev_err(&ndev->dev->dev,
    > + "Memory registrations not supported.\n");
    > + goto out_free_mr;
    > + }
    > +
    > + list_add(&ndev->entry, &device_list);
    > +out_unlock:
    > + mutex_unlock(&device_list_mutex);
    > + return ndev;
    > +
    > +out_free_mr:
    > + if (!register_always)
    > + ib_dereg_mr(ndev->mr);
    > +out_free_pd:
    > + ib_dealloc_pd(ndev->pd);
    > +out_free_dev:
    > + kfree(ndev);
    > +out_err:
    > + mutex_unlock(&device_list_mutex);
    > + return NULL;
    > +}
    > +
    > +static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue)
    > +{
    > + struct nvme_rdma_device *dev = queue->device;
    > + struct ib_device *ibdev = dev->dev;
    > +
    > + rdma_destroy_qp(queue->cm_id);
    > + ib_free_cq(queue->ib_cq);
    > +
    > + nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
    > + sizeof(struct nvme_completion), DMA_FROM_DEVICE);
    > +
    > + nvme_rdma_dev_put(dev);
    > +}
    > +
    > +static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_device *dev)
    > +{
    > + struct ib_device *ibdev = dev->dev;
    > + const int send_wr_factor = 3; /* MR, SEND, INV */
    > + const int cq_factor = send_wr_factor + 1; /* + RECV */
    > + int comp_vector, idx = nvme_rdma_queue_idx(queue);
    > +
    > + int ret;
    > +
    > + queue->device = dev;
    > +
    > + /*
    > + * The admin queue is barely used once the controller is live, so don't
    > + * bother to spread it out.
    > + */
    > + if (idx == 0)
    > + comp_vector = 0;
    > + else
    > + comp_vector = idx % ibdev->num_comp_vectors;
    > +
    > +
    > + /* +1 for ib_stop_cq */
    > + queue->ib_cq = ib_alloc_cq(dev->dev, queue,
    > + cq_factor * queue->queue_size + 1, comp_vector,
    > + IB_POLL_SOFTIRQ);
    > + if (IS_ERR(queue->ib_cq)) {
    > + ret = PTR_ERR(queue->ib_cq);
    > + goto out;
    > + }
    > +
    > + ret = nvme_rdma_create_qp(queue, send_wr_factor);
    > + if (ret)
    > + goto out_destroy_ib_cq;
    > +
    > + queue->rsp_ring = nvme_rdma_alloc_ring(ibdev, queue->queue_size,
    > + sizeof(struct nvme_completion), DMA_FROM_DEVICE);
    > + if (!queue->rsp_ring) {
    > + ret = -ENOMEM;
    > + goto out_destroy_qp;
    > + }
    > +
    > + return 0;
    > +
    > +out_destroy_qp:
    > + ib_destroy_qp(queue->qp);
    > +out_destroy_ib_cq:
    > + ib_free_cq(queue->ib_cq);
    > +out:
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_init_queue(struct nvme_rdma_ctrl *ctrl,
    > + int idx, size_t queue_size)
    > +{
    > + struct nvme_rdma_queue *queue;
    > + int ret;
    > +
    > + queue = &ctrl->queues[idx];
    > + queue->ctrl = ctrl;
    > + init_completion(&queue->cm_done);
    > +
    > + if (idx > 0)
    > + queue->cmnd_capsule_len = ctrl->ctrl.ioccsz * 16;
    > + else
    > + queue->cmnd_capsule_len = sizeof(struct nvme_command);
    > +
    > + queue->queue_size = queue_size;
    > +
    > + queue->cm_id = rdma_create_id(&init_net, nvme_rdma_cm_handler, queue,
    > + RDMA_PS_TCP, IB_QPT_RC);
    > + if (IS_ERR(queue->cm_id)) {
    > + dev_info(ctrl->ctrl.device,
    > + "failed to create CM ID: %ld\n", PTR_ERR(queue->cm_id));
    > + return PTR_ERR(queue->cm_id);
    > + }
    > +
    > + queue->cm_error = -ETIMEDOUT;
    > + ret = rdma_resolve_addr(queue->cm_id, NULL, &ctrl->addr,
    > + NVME_RDMA_CONNECT_TIMEOUT_MS);
    > + if (ret) {
    > + dev_info(ctrl->ctrl.device,
    > + "rdma_resolve_addr failed (%d).\n", ret);
    > + goto out_destroy_cm_id;
    > + }
    > +
    > + ret = nvme_rdma_wait_for_cm(queue);
    > + if (ret) {
    > + dev_info(ctrl->ctrl.device,
    > + "rdma_resolve_addr wait failed (%d).\n", ret);
    > + goto out_destroy_cm_id;
    > + }
    > +
    > + set_bit(NVME_RDMA_Q_CONNECTED, &queue->flags);
    > +
    > + return 0;
    > +
    > +out_destroy_cm_id:
    > + rdma_destroy_id(queue->cm_id);
    > + return ret;
    > +}
    > +
    > +static void nvme_rdma_free_queue(struct nvme_rdma_queue *queue)
    > +{
    > + if (!test_and_clear_bit(NVME_RDMA_Q_CONNECTED, &queue->flags))
    > + return;
    > +
    > + rdma_disconnect(queue->cm_id);
    > + ib_drain_qp(queue->qp);
    > + nvme_rdma_destroy_queue_ib(queue);
    > + rdma_destroy_id(queue->cm_id);
    > +}
    > +
    > +static void nvme_rdma_free_io_queues(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + int i;
    > +
    > + for (i = 1; i < ctrl->queue_count; i++)
    > + nvme_rdma_free_queue(&ctrl->queues[i]);
    > +}
    > +
    > +static int nvme_rdma_connect_io_queues(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + int i, ret = 0;
    > +
    > + for (i = 1; i < ctrl->queue_count; i++) {
    > + ret = nvmf_connect_io_queue(&ctrl->ctrl, i);
    > + if (ret)
    > + break;
    > + }
    > +
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_init_io_queues(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + int i, ret;
    > +
    > + for (i = 1; i < ctrl->queue_count; i++) {
    > + ret = nvme_rdma_init_queue(ctrl, i, ctrl->ctrl.sqsize);
    > + if (ret) {
    > + dev_info(ctrl->ctrl.device,
    > + "failed to initialize i/o queue: %d\n", ret);
    > + goto out_free_queues;
    > + }
    > + }
    > +
    > + return 0;
    > +
    > +out_free_queues:
    > + for (; i >= 1; i--)
    > + nvme_rdma_free_queue(&ctrl->queues[i]);
    > +
    > + return ret;
    > +}
    > +
    > +static void nvme_rdma_destroy_admin_queue(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + nvme_rdma_free_qe(ctrl->queues[0].device->dev, &ctrl->async_event_sqe,
    > + sizeof(struct nvme_command), DMA_TO_DEVICE);
    > + nvme_rdma_free_queue(&ctrl->queues[0]);
    > + blk_cleanup_queue(ctrl->ctrl.admin_q);
    > + blk_mq_free_tag_set(&ctrl->admin_tag_set);
    > + nvme_rdma_dev_put(ctrl->device);
    > +}
    > +
    > +static void nvme_rdma_free_ctrl(struct nvme_ctrl *nctrl)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
    > +
    > + if (list_empty(&ctrl->list))
    > + goto free_ctrl;
    > +
    > + mutex_lock(&nvme_rdma_ctrl_mutex);
    > + list_del(&ctrl->list);
    > + mutex_unlock(&nvme_rdma_ctrl_mutex);
    > +
    > + if (ctrl->ctrl.tagset) {
    > + blk_cleanup_queue(ctrl->ctrl.connect_q);
    > + blk_mq_free_tag_set(&ctrl->tag_set);
    > + nvme_rdma_dev_put(ctrl->device);
    > + }
    > + kfree(ctrl->queues);
    > + nvmf_free_options(nctrl->opts);
    > +free_ctrl:
    > + kfree(ctrl);
    > +}
    > +
    > +static void nvme_rdma_reconnect_ctrl_work(struct work_struct *work)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = container_of(to_delayed_work(work),
    > + struct nvme_rdma_ctrl, reconnect_work);
    > + bool changed;
    > + int ret;
    > +
    > + if (ctrl->queue_count > 1) {
    > + nvme_rdma_free_io_queues(ctrl);
    > +
    > + ret = blk_mq_reinit_tagset(&ctrl->tag_set);
    > + if (ret)
    > + goto requeue;
    > + }
    > +
    > + nvme_rdma_free_queue(&ctrl->queues[0]);
    > +
    > + ret = blk_mq_reinit_tagset(&ctrl->admin_tag_set);
    > + if (ret)
    > + goto requeue;
    > +
    > + ret = nvme_rdma_init_queue(ctrl, 0, NVMF_AQ_DEPTH);
    > + if (ret)
    > + goto requeue;
    > +
    > + blk_mq_start_stopped_hw_queues(ctrl->ctrl.admin_q, true);
    > +
    > + ret = nvmf_connect_admin_queue(&ctrl->ctrl);
    > + if (ret)
    > + goto stop_admin_q;
    > +
    > + ret = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap);
    > + if (ret)
    > + goto stop_admin_q;
    > +
    > + nvme_start_keep_alive(&ctrl->ctrl);
    > +
    > + if (ctrl->queue_count > 1) {
    > + ret = nvme_rdma_init_io_queues(ctrl);
    > + if (ret)
    > + goto stop_admin_q;
    > +
    > + ret = nvme_rdma_connect_io_queues(ctrl);
    > + if (ret)
    > + goto stop_admin_q;
    > + }
    > +
    > + changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
    > + WARN_ON_ONCE(!changed);
    > +
    > + if (ctrl->queue_count > 1)
    > + nvme_start_queues(&ctrl->ctrl);
    > +
    > + dev_info(ctrl->ctrl.device, "Successfully reconnected\n");
    > +
    > + return;
    > +
    > +stop_admin_q:
    > + blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
    > +requeue:
    > + /* Make sure we are not resetting/deleting */
    > + if (ctrl->ctrl.state == NVME_CTRL_RECONNECTING) {
    > + dev_info(ctrl->ctrl.device,
    > + "Failed reconnect attempt, requeueing...\n");
    > + queue_delayed_work(nvme_rdma_wq, &ctrl->reconnect_work,
    > + ctrl->reconnect_delay * HZ);
    > + }
    > +}
    > +
    > +static void nvme_rdma_error_recovery_work(struct work_struct *work)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = container_of(work,
    > + struct nvme_rdma_ctrl, err_work);
    > +
    > + nvme_stop_keep_alive(&ctrl->ctrl);
    > + if (ctrl->queue_count > 1)
    > + nvme_stop_queues(&ctrl->ctrl);
    > + blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
    > +
    > + /* We must take care of fastfail/requeue all our inflight requests */
    > + if (ctrl->queue_count > 1)
    > + blk_mq_tagset_busy_iter(&ctrl->tag_set,
    > + nvme_cancel_request, &ctrl->ctrl);
    > + blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
    > + nvme_cancel_request, &ctrl->ctrl);
    > +
    > + dev_info(ctrl->ctrl.device, "reconnecting in %d seconds\n",
    > + ctrl->reconnect_delay);
    > +
    > + queue_delayed_work(nvme_rdma_wq, &ctrl->reconnect_work,
    > + ctrl->reconnect_delay * HZ);
    > +}
    > +
    > +static void nvme_rdma_error_recovery(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RECONNECTING))
    > + return;
    > +
    > + queue_work(nvme_rdma_wq, &ctrl->err_work);
    > +}
    > +
    > +static void nvme_rdma_wr_error(struct ib_cq *cq, struct ib_wc *wc,
    > + const char *op)
    > +{
    > + struct nvme_rdma_queue *queue = cq->cq_context;
    > + struct nvme_rdma_ctrl *ctrl = queue->ctrl;
    > +
    > + if (ctrl->ctrl.state == NVME_CTRL_LIVE)
    > + dev_info(ctrl->ctrl.device,
    > + "%s for CQE 0x%p failed with status %s (%d)\n",
    > + op, wc->wr_cqe,
    > + ib_wc_status_msg(wc->status), wc->status);
    > + nvme_rdma_error_recovery(ctrl);
    > +}
    > +
    > +static void nvme_rdma_memreg_done(struct ib_cq *cq, struct ib_wc *wc)
    > +{
    > + if (unlikely(wc->status != IB_WC_SUCCESS))
    > + nvme_rdma_wr_error(cq, wc, "MEMREG");
    > +}
    > +
    > +static void nvme_rdma_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc)
    > +{
    > + if (unlikely(wc->status != IB_WC_SUCCESS))
    > + nvme_rdma_wr_error(cq, wc, "LOCAL_INV");
    > +}
    > +
    > +static int nvme_rdma_inv_rkey(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_request *req)
    > +{
    > + struct ib_send_wr *bad_wr;
    > + struct ib_send_wr wr = {
    > + .opcode = IB_WR_LOCAL_INV,
    > + .next = NULL,
    > + .num_sge = 0,
    > + .send_flags = 0,
    > + .ex.invalidate_rkey = req->mr->rkey,
    > + };
    > +
    > + req->reg_cqe.done = nvme_rdma_inv_rkey_done;
    > + wr.wr_cqe = &req->reg_cqe;
    > +
    > + return ib_post_send(queue->qp, &wr, &bad_wr);
    > +}
    > +
    > +static void nvme_rdma_unmap_data(struct nvme_rdma_queue *queue,
    > + struct request *rq)
    > +{
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + struct nvme_rdma_ctrl *ctrl = queue->ctrl;
    > + struct nvme_rdma_device *dev = queue->device;
    > + struct ib_device *ibdev = dev->dev;
    > + int res;
    > +
    > + if (!blk_rq_bytes(rq))
    > + return;
    > +
    > + if (req->need_inval) {
    > + res = nvme_rdma_inv_rkey(queue, req);
    > + if (res < 0) {
    > + dev_err(ctrl->ctrl.device,
    > + "Queueing INV WR for rkey %#x failed (%d)\n",
    > + req->mr->rkey, res);
    > + nvme_rdma_error_recovery(queue->ctrl);
    > + }
    > + }
    > +
    > + ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
    > + req->nents, rq_data_dir(rq) ==
    > + WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
    > +
    > + nvme_cleanup_cmd(rq);
    > + sg_free_table_chained(&req->sg_table, true);
    > +}
    > +
    > +static int nvme_rdma_set_sg_null(struct nvme_command *c)
    > +{
    > + struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
    > +
    > + sg->addr = 0;
    > + put_unaligned_le24(0, sg->length);
    > + put_unaligned_le32(0, sg->key);
    > + sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
    > + return 0;
    > +}
    > +
    > +static int nvme_rdma_map_sg_inline(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_request *req, struct nvme_command *c)
    > +{
    > + struct nvme_sgl_desc *sg = &c->common.dptr.sgl;
    > +
    > + req->sge[1].addr = sg_dma_address(req->sg_table.sgl);
    > + req->sge[1].length = sg_dma_len(req->sg_table.sgl);
    > + req->sge[1].lkey = queue->device->pd->local_dma_lkey;
    > +
    > + sg->addr = cpu_to_le64(queue->ctrl->ctrl.icdoff);
    > + sg->length = cpu_to_le32(sg_dma_len(req->sg_table.sgl));
    > + sg->type = (NVME_SGL_FMT_DATA_DESC << 4) | NVME_SGL_FMT_OFFSET;
    > +
    > + req->inline_data = true;
    > + req->num_sge++;
    > + return 0;
    > +}
    > +
    > +static int nvme_rdma_map_sg_single(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_request *req, struct nvme_command *c)
    > +{
    > + struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
    > +
    > + sg->addr = cpu_to_le64(sg_dma_address(req->sg_table.sgl));
    > + put_unaligned_le24(sg_dma_len(req->sg_table.sgl), sg->length);
    > + put_unaligned_le32(queue->device->mr->rkey, sg->key);
    > + sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
    > + return 0;
    > +}
    > +
    > +static int nvme_rdma_map_sg_fr(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_request *req, struct nvme_command *c,
    > + int count)
    > +{
    > + struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
    > + int nr;
    > +
    > + nr = ib_map_mr_sg(req->mr, req->sg_table.sgl, count, NULL, PAGE_SIZE);
    > + if (nr < count) {
    > + if (nr < 0)
    > + return nr;
    > + return -EINVAL;
    > + }
    > +
    > + ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey));
    > +
    > + req->reg_cqe.done = nvme_rdma_memreg_done;
    > + memset(&req->reg_wr, 0, sizeof(req->reg_wr));
    > + req->reg_wr.wr.opcode = IB_WR_REG_MR;
    > + req->reg_wr.wr.wr_cqe = &req->reg_cqe;
    > + req->reg_wr.wr.num_sge = 0;
    > + req->reg_wr.mr = req->mr;
    > + req->reg_wr.key = req->mr->rkey;
    > + req->reg_wr.access = IB_ACCESS_LOCAL_WRITE |
    > + IB_ACCESS_REMOTE_READ |
    > + IB_ACCESS_REMOTE_WRITE;
    > +
    > + req->need_inval = true;
    > +
    > + sg->addr = cpu_to_le64(req->mr->iova);
    > + put_unaligned_le24(req->mr->length, sg->length);
    > + put_unaligned_le32(req->mr->rkey, sg->key);
    > + sg->type = (NVME_KEY_SGL_FMT_DATA_DESC << 4) |
    > + NVME_SGL_FMT_INVALIDATE;
    > +
    > + return 0;
    > +}
    > +
    > +static int nvme_rdma_map_data(struct nvme_rdma_queue *queue,
    > + struct request *rq, unsigned int map_len,
    > + struct nvme_command *c)
    > +{
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + struct nvme_rdma_device *dev = queue->device;
    > + struct ib_device *ibdev = dev->dev;
    > + int nents, count;
    > + int ret;
    > +
    > + req->num_sge = 1;
    > + req->inline_data = false;
    > + req->need_inval = false;
    > +
    > + c->common.flags |= NVME_CMD_SGL_METABUF;
    > +
    > + if (!blk_rq_bytes(rq))
    > + return nvme_rdma_set_sg_null(c);
    > +
    > + req->sg_table.sgl = req->first_sgl;
    > + ret = sg_alloc_table_chained(&req->sg_table, rq->nr_phys_segments,
    > + req->sg_table.sgl);
    > + if (ret)
    > + return -ENOMEM;
    > +
    > + nents = blk_rq_map_sg(rq->q, rq, req->sg_table.sgl);
    > + BUG_ON(nents > rq->nr_phys_segments);
    > + req->nents = nents;
    > +
    > + count = ib_dma_map_sg(ibdev, req->sg_table.sgl, nents,
    > + rq_data_dir(rq) == WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
    > + if (unlikely(count <= 0)) {
    > + sg_free_table_chained(&req->sg_table, true);
    > + return -EIO;
    > + }
    > +
    > + if (count == 1) {
    > + if (rq_data_dir(rq) == WRITE &&
    > + map_len <= nvme_rdma_inline_data_size(queue) &&
    > + nvme_rdma_queue_idx(queue))
    > + return nvme_rdma_map_sg_inline(queue, req, c);
    > +
    > + if (!register_always)
    > + return nvme_rdma_map_sg_single(queue, req, c);
    > + }
    > +
    > + return nvme_rdma_map_sg_fr(queue, req, c, count);
    > +}
    > +
    > +static void nvme_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
    > +{
    > + if (unlikely(wc->status != IB_WC_SUCCESS))
    > + nvme_rdma_wr_error(cq, wc, "SEND");
    > +}
    > +
    > +static int nvme_rdma_post_send(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_qe *qe, struct ib_sge *sge, u32 num_sge,
    > + struct ib_send_wr *first, bool flush)
    > +{
    > + struct ib_send_wr wr, *bad_wr;
    > + int ret;
    > +
    > + sge->addr = qe->dma;
    > + sge->length = sizeof(struct nvme_command),
    > + sge->lkey = queue->device->pd->local_dma_lkey;
    > +
    > + qe->cqe.done = nvme_rdma_send_done;
    > +
    > + wr.next = NULL;
    > + wr.wr_cqe = &qe->cqe;
    > + wr.sg_list = sge;
    > + wr.num_sge = num_sge;
    > + wr.opcode = IB_WR_SEND;
    > + wr.send_flags = 0;
    > +
    > + /*
    > + * Unsignalled send completions are another giant desaster in the
    > + * IB Verbs spec: If we don't regularly post signalled sends
    > + * the send queue will fill up and only a QP reset will rescue us.
    > + * Would have been way to obvious to handle this in hardware or
    > + * at least the RDMA stack..
    > + *
    > + * This messy and racy code sniplet is copy and pasted from the iSER
    > + * initiator, and the magic '32' comes from there as well.
    > + *
    > + * Always signal the flushes. The magic request used for the flush
    > + * sequencer is not allocated in our driver's tagset and it's
    > + * triggered to be freed by blk_cleanup_queue(). So we need to
    > + * always mark it as signaled to ensure that the "wr_cqe", which is
    > + * embeded in request's payload, is not freed when __ib_process_cq()
    > + * calls wr_cqe->done().
    > + */
    > + if ((++queue->sig_count % 32) == 0 || flush)
    > + wr.send_flags |= IB_SEND_SIGNALED;
    > +
    > + if (first)
    > + first->next = &wr;
    > + else
    > + first = &wr;
    > +
    > + ret = ib_post_send(queue->qp, first, &bad_wr);
    > + if (ret) {
    > + dev_err(queue->ctrl->ctrl.device,
    > + "%s failed with error code %d\n", __func__, ret);
    > + }
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_post_recv(struct nvme_rdma_queue *queue,
    > + struct nvme_rdma_qe *qe)
    > +{
    > + struct ib_recv_wr wr, *bad_wr;
    > + struct ib_sge list;
    > + int ret;
    > +
    > + list.addr = qe->dma;
    > + list.length = sizeof(struct nvme_completion);
    > + list.lkey = queue->device->pd->local_dma_lkey;
    > +
    > + qe->cqe.done = nvme_rdma_recv_done;
    > +
    > + wr.next = NULL;
    > + wr.wr_cqe = &qe->cqe;
    > + wr.sg_list = &list;
    > + wr.num_sge = 1;
    > +
    > + ret = ib_post_recv(queue->qp, &wr, &bad_wr);
    > + if (ret) {
    > + dev_err(queue->ctrl->ctrl.device,
    > + "%s failed with error code %d\n", __func__, ret);
    > + }
    > + return ret;
    > +}
    > +
    > +static struct blk_mq_tags *nvme_rdma_tagset(struct nvme_rdma_queue *queue)
    > +{
    > + u32 queue_idx = nvme_rdma_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_rdma_submit_async_event(struct nvme_ctrl *arg, int aer_idx)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(arg);
    > + struct nvme_rdma_queue *queue = &ctrl->queues[0];
    > + struct ib_device *dev = queue->device->dev;
    > + struct nvme_rdma_qe *sqe = &ctrl->async_event_sqe;
    > + struct nvme_command *cmd = sqe->data;
    > + struct ib_sge sge;
    > + int ret;
    > +
    > + if (WARN_ON_ONCE(aer_idx != 0))
    > + return;
    > +
    > + ib_dma_sync_single_for_cpu(dev, sqe->dma, sizeof(*cmd), DMA_TO_DEVICE);
    > +
    > + memset(cmd, 0, sizeof(*cmd));
    > + cmd->common.opcode = nvme_admin_async_event;
    > + cmd->common.command_id = NVME_RDMA_AQ_BLKMQ_DEPTH;
    > + nvme_rdma_set_sg_null(cmd);
    > +
    > + ib_dma_sync_single_for_device(dev, sqe->dma, sizeof(*cmd),
    > + DMA_TO_DEVICE);
    > +
    > + ret = nvme_rdma_post_send(queue, sqe, &sge, 1, NULL, false);
    > + WARN_ON_ONCE(ret);
    > +}
    > +
    > +static int nvme_rdma_process_nvme_rsp(struct nvme_rdma_queue *queue,
    > + struct nvme_completion *cqe, struct ib_wc *wc, int tag)
    > +{
    > + u16 status = le16_to_cpu(cqe->status);
    > + struct request *rq;
    > + struct nvme_rdma_request *req;
    > + int ret = 0;
    > +
    > + status >>= 1;
    > +
    > + rq = blk_mq_tag_to_rq(nvme_rdma_tagset(queue), cqe->command_id);
    > + if (!rq) {
    > + dev_err(queue->ctrl->ctrl.device,
    > + "tag 0x%x on QP %#x not found\n",
    > + cqe->command_id, queue->qp->qp_num);
    > + nvme_rdma_error_recovery(queue->ctrl);
    > + return ret;
    > + }
    > + req = blk_mq_rq_to_pdu(rq);
    > +
    > + if (rq->cmd_type == REQ_TYPE_DRV_PRIV && rq->special)
    > + memcpy(rq->special, cqe, sizeof(*cqe));
    > +
    > + if (rq->tag == tag)
    > + ret = 1;
    > +
    > + if ((wc->wc_flags & IB_WC_WITH_INVALIDATE) &&
    > + wc->ex.invalidate_rkey == req->mr->rkey)
    > + req->need_inval = false;
    > +
    > + blk_mq_complete_request(rq, status);
    > +
    > + return ret;
    > +}
    > +
    > +static int __nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc, int tag)
    > +{
    > + struct nvme_rdma_qe *qe =
    > + container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
    > + struct nvme_rdma_queue *queue = cq->cq_context;
    > + struct ib_device *ibdev = queue->device->dev;
    > + struct nvme_completion *cqe = qe->data;
    > + const size_t len = sizeof(struct nvme_completion);
    > + int ret = 0;
    > +
    > + if (unlikely(wc->status != IB_WC_SUCCESS)) {
    > + nvme_rdma_wr_error(cq, wc, "RECV");
    > + return 0;
    > + }
    > +
    > + ib_dma_sync_single_for_cpu(ibdev, qe->dma, len, DMA_FROM_DEVICE);
    > + /*
    > + * 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_rdma_queue_idx(queue) == 0 &&
    > + cqe->command_id >= NVME_RDMA_AQ_BLKMQ_DEPTH))
    > + nvme_complete_async_event(&queue->ctrl->ctrl, cqe);
    > + else
    > + ret = nvme_rdma_process_nvme_rsp(queue, cqe, wc, tag);
    > + ib_dma_sync_single_for_device(ibdev, qe->dma, len, DMA_FROM_DEVICE);
    > +
    > + nvme_rdma_post_recv(queue, qe);
    > + return ret;
    > +}
    > +
    > +static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
    > +{
    > + __nvme_rdma_recv_done(cq, wc, -1);
    > +}
    > +
    > +static int nvme_rdma_conn_established(struct nvme_rdma_queue *queue)
    > +{
    > + int ret, i;
    > +
    > + for (i = 0; i < queue->queue_size; i++) {
    > + ret = nvme_rdma_post_recv(queue, &queue->rsp_ring[i]);
    > + if (ret)
    > + goto out_destroy_queue_ib;
    > + }
    > +
    > + return 0;
    > +
    > +out_destroy_queue_ib:
    > + nvme_rdma_destroy_queue_ib(queue);
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_conn_rejected(struct nvme_rdma_queue *queue,
    > + struct rdma_cm_event *ev)
    > +{
    > + if (ev->status == IB_CM_REJ_CONSUMER_DEFINED) {
    > + struct nvme_rdma_cm_rej *rej =
    > + (struct nvme_rdma_cm_rej *)ev->param.conn.private_data;
    > +
    > + dev_err(queue->ctrl->ctrl.device,
    > + "Connect rejected, status %d.", le16_to_cpu(rej->sts));
    > + /* XXX: Think of something clever to do here... */
    > + } else {
    > + dev_err(queue->ctrl->ctrl.device,
    > + "Connect rejected, no private data.\n");
    > + }
    > +
    > + return -ECONNRESET;
    > +}
    > +
    > +static int nvme_rdma_addr_resolved(struct nvme_rdma_queue *queue)
    > +{
    > + struct nvme_rdma_device *dev;
    > + int ret;
    > +
    > + dev = nvme_rdma_find_get_device(queue->cm_id);
    > + if (!dev) {
    > + dev_err(queue->cm_id->device->dma_device,
    > + "no client data found!\n");
    > + return -ECONNREFUSED;
    > + }
    > +
    > + ret = nvme_rdma_create_queue_ib(queue, dev);
    > + if (ret) {
    > + nvme_rdma_dev_put(dev);
    > + goto out;
    > + }
    > +
    > + ret = rdma_resolve_route(queue->cm_id, NVME_RDMA_CONNECT_TIMEOUT_MS);
    > + if (ret) {
    > + dev_err(queue->ctrl->ctrl.device,
    > + "rdma_resolve_route failed (%d).\n",
    > + queue->cm_error);
    > + goto out_destroy_queue;
    > + }
    > +
    > + return 0;
    > +
    > +out_destroy_queue:
    > + nvme_rdma_destroy_queue_ib(queue);
    > +out:
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_route_resolved(struct nvme_rdma_queue *queue)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = queue->ctrl;
    > + struct rdma_conn_param param = { };
    > + struct nvme_rdma_cm_req priv;
    > + int ret;
    > +
    > + param.qp_num = queue->qp->qp_num;
    > + param.flow_control = 1;
    > +
    > + param.responder_resources = queue->device->dev->attrs.max_qp_rd_atom;
    > + /* rdma_cm will clamp down to max QP retry count (7) */
    > + param.retry_count = ctrl->tl_retry_count;
    > + param.rnr_retry_count = 7;
    > + param.private_data = &priv;
    > + param.private_data_len = sizeof(priv);
    > +
    > + priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
    > + priv.qid = cpu_to_le16(nvme_rdma_queue_idx(queue));
    > + priv.hrqsize = cpu_to_le16(queue->queue_size);
    > + priv.hsqsize = cpu_to_le16(queue->queue_size);
    > +
    > + ret = rdma_connect(queue->cm_id, &param);
    > + if (ret) {
    > + dev_err(ctrl->ctrl.device,
    > + "rdma_connect failed (%d).\n", ret);
    > + goto out_destroy_queue_ib;
    > + }
    > +
    > + return 0;
    > +
    > +out_destroy_queue_ib:
    > + nvme_rdma_destroy_queue_ib(queue);
    > + return ret;
    > +}
    > +
    > +/**
    > + * nvme_rdma_device_unplug() - Handle RDMA device unplug
    > + * @queue: Queue that owns the cm_id that caught the event
    > + *
    > + * DEVICE_REMOVAL event notifies us that the RDMA device is about
    > + * to unplug so we should take care of destroying our RDMA resources.
    > + * This event will be generated for each allocated cm_id.
    > + *
    > + * In our case, the RDMA resources are managed per controller and not
    > + * only per queue. So the way we handle this is we trigger an implicit
    > + * controller deletion upon the first DEVICE_REMOVAL event we see, and
    > + * hold the event inflight until the controller deletion is completed.
    > + *
    > + * One exception that we need to handle is the destruction of the cm_id
    > + * that caught the event. Since we hold the callout until the controller
    > + * deletion is completed, we'll deadlock if the controller deletion will
    > + * call rdma_destroy_id on this queue's cm_id. Thus, we claim ownership
    > + * of destroying this queue before-hand, destroy the queue resources
    > + * after the controller deletion completed with the exception of destroying
    > + * the cm_id implicitely by returning a non-zero rc to the callout.
    > + */
    > +static int nvme_rdma_device_unplug(struct nvme_rdma_queue *queue)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = queue->ctrl;
    > + int ret, ctrl_deleted = 0;
    > +
    > + /* First disable the queue so ctrl delete won't free it */
    > + if (!test_and_clear_bit(NVME_RDMA_Q_CONNECTED, &queue->flags))
    > + goto out;
    > +
    > + /* delete the controller */
    > + ret = __nvme_rdma_del_ctrl(ctrl);
    > + if (!ret) {
    > + dev_warn(ctrl->ctrl.device,
    > + "Got rdma device removal event, deleting ctrl\n");
    > + flush_work(&ctrl->delete_work);
    > +
    > + /* Return non-zero so the cm_id will destroy implicitly */
    > + ctrl_deleted = 1;
    > +
    > + /* Free this queue ourselves */
    > + rdma_disconnect(queue->cm_id);
    > + ib_drain_qp(queue->qp);
    > + nvme_rdma_destroy_queue_ib(queue);
    > + }
    > +
    > +out:
    > + return ctrl_deleted;
    > +}
    > +
    > +static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
    > + struct rdma_cm_event *ev)
    > +{
    > + struct nvme_rdma_queue *queue = cm_id->context;
    > + int cm_error = 0;
    > +
    > + dev_dbg(queue->ctrl->ctrl.device, "%s (%d): status %d id %p\n",
    > + rdma_event_msg(ev->event), ev->event,
    > + ev->status, cm_id);
    > +
    > + switch (ev->event) {
    > + case RDMA_CM_EVENT_ADDR_RESOLVED:
    > + cm_error = nvme_rdma_addr_resolved(queue);
    > + break;
    > + case RDMA_CM_EVENT_ROUTE_RESOLVED:
    > + cm_error = nvme_rdma_route_resolved(queue);
    > + break;
    > + case RDMA_CM_EVENT_ESTABLISHED:
    > + queue->cm_error = nvme_rdma_conn_established(queue);
    > + /* complete cm_done regardless of success/failure */
    > + complete(&queue->cm_done);
    > + return 0;
    > + case RDMA_CM_EVENT_REJECTED:
    > + cm_error = nvme_rdma_conn_rejected(queue, ev);
    > + break;
    > + case RDMA_CM_EVENT_ADDR_ERROR:
    > + case RDMA_CM_EVENT_ROUTE_ERROR:
    > + case RDMA_CM_EVENT_CONNECT_ERROR:
    > + case RDMA_CM_EVENT_UNREACHABLE:
    > + dev_dbg(queue->ctrl->ctrl.device,
    > + "CM error event %d\n", ev->event);
    > + cm_error = -ECONNRESET;
    > + break;
    > + case RDMA_CM_EVENT_DISCONNECTED:
    > + case RDMA_CM_EVENT_ADDR_CHANGE:
    > + case RDMA_CM_EVENT_TIMEWAIT_EXIT:
    > + dev_dbg(queue->ctrl->ctrl.device,
    > + "disconnect received - connection closed\n");
    > + nvme_rdma_error_recovery(queue->ctrl);
    > + break;
    > + case RDMA_CM_EVENT_DEVICE_REMOVAL:
    > + /* return 1 means impliciy CM ID destroy */
    > + return nvme_rdma_device_unplug(queue);
    > + default:
    > + dev_err(queue->ctrl->ctrl.device,
    > + "Unexpected RDMA CM event (%d)\n", ev->event);
    > + nvme_rdma_error_recovery(queue->ctrl);
    > + break;
    > + }
    > +
    > + if (cm_error) {
    > + queue->cm_error = cm_error;
    > + complete(&queue->cm_done);
    > + }
    > +
    > + return 0;
    > +}
    > +
    > +static enum blk_eh_timer_return
    > +nvme_rdma_timeout(struct request *rq, bool reserved)
    > +{
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > +
    > + /* queue error recovery */
    > + nvme_rdma_error_recovery(req->queue->ctrl);
    > +
    > + /* fail with DNR on cmd timeout */
    > + rq->errors = NVME_SC_ABORT_REQ | NVME_SC_DNR;
    > +
    > + return BLK_EH_HANDLED;
    > +}
    > +
    > +static int nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
    > + const struct blk_mq_queue_data *bd)
    > +{
    > + struct nvme_ns *ns = hctx->queue->queuedata;
    > + struct nvme_rdma_queue *queue = hctx->driver_data;
    > + struct request *rq = bd->rq;
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + struct nvme_rdma_qe *sqe = &req->sqe;
    > + struct nvme_command *c = sqe->data;
    > + bool flush = false;
    > + struct ib_device *dev;
    > + unsigned int map_len;
    > + int ret;
    > +
    > + WARN_ON_ONCE(rq->tag < 0);
    > +
    > + dev = queue->device->dev;
    > + ib_dma_sync_single_for_cpu(dev, sqe->dma,
    > + sizeof(struct nvme_command), DMA_TO_DEVICE);
    > +
    > + ret = nvme_setup_cmd(ns, rq, c);
    > + if (ret)
    > + return ret;
    > +
    > + c->common.command_id = rq->tag;
    > + blk_mq_start_request(rq);
    > +
    > + map_len = nvme_map_len(rq);
    > + ret = nvme_rdma_map_data(queue, rq, map_len, c);
    > + if (ret < 0) {
    > + dev_err(queue->ctrl->ctrl.device,
    > + "Failed to map data (%d)\n", ret);
    > + nvme_cleanup_cmd(rq);
    > + goto err;
    > + }
    > +
    > + ib_dma_sync_single_for_device(dev, sqe->dma,
    > + sizeof(struct nvme_command), DMA_TO_DEVICE);
    > +
    > + if (rq->cmd_type == REQ_TYPE_FS && (rq->cmd_flags & REQ_FLUSH))
    > + flush = true;
    > + ret = nvme_rdma_post_send(queue, sqe, req->sge, req->num_sge,
    > + req->need_inval ? &req->reg_wr.wr : NULL, flush);
    > + if (ret) {
    > + nvme_rdma_unmap_data(queue, rq);
    > + goto err;
    > + }
    > +
    > + return BLK_MQ_RQ_QUEUE_OK;
    > +err:
    > + return (ret == -ENOMEM || ret == -EAGAIN) ?
    > + BLK_MQ_RQ_QUEUE_BUSY : BLK_MQ_RQ_QUEUE_ERROR;
    > +}
    > +
    > +static int nvme_rdma_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
    > +{
    > + struct nvme_rdma_queue *queue = hctx->driver_data;
    > + struct ib_cq *cq = queue->ib_cq;
    > + struct ib_wc wc;
    > + int found = 0;
    > +
    > + ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
    > + while (ib_poll_cq(cq, 1, &wc) > 0) {
    > + struct ib_cqe *cqe = wc.wr_cqe;
    > +
    > + if (cqe) {
    > + if (cqe->done == nvme_rdma_recv_done)
    > + found |= __nvme_rdma_recv_done(cq, &wc, tag);
    > + else
    > + cqe->done(cq, &wc);
    > + }
    > + }
    > +
    > + return found;
    > +}
    > +
    > +static void nvme_rdma_complete_rq(struct request *rq)
    > +{
    > + struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
    > + struct nvme_rdma_queue *queue = req->queue;
    > + int error = 0;
    > +
    > + nvme_rdma_unmap_data(queue, rq);
    > +
    > + if (unlikely(rq->errors)) {
    > + if (nvme_req_needs_retry(rq, rq->errors)) {
    > + nvme_requeue_req(rq);
    > + return;
    > + }
    > +
    > + if (rq->cmd_type == REQ_TYPE_DRV_PRIV)
    > + error = rq->errors;
    > + else
    > + error = nvme_error_status(rq->errors);
    > + }
    > +
    > + blk_mq_end_request(rq, error);
    > +}
    > +
    > +static struct blk_mq_ops nvme_rdma_mq_ops = {
    > + .queue_rq = nvme_rdma_queue_rq,
    > + .complete = nvme_rdma_complete_rq,
    > + .map_queue = blk_mq_map_queue,
    > + .init_request = nvme_rdma_init_request,
    > + .exit_request = nvme_rdma_exit_request,
    > + .reinit_request = nvme_rdma_reinit_request,
    > + .init_hctx = nvme_rdma_init_hctx,
    > + .poll = nvme_rdma_poll,
    > + .timeout = nvme_rdma_timeout,
    > +};
    > +
    > +static struct blk_mq_ops nvme_rdma_admin_mq_ops = {
    > + .queue_rq = nvme_rdma_queue_rq,
    > + .complete = nvme_rdma_complete_rq,
    > + .map_queue = blk_mq_map_queue,
    > + .init_request = nvme_rdma_init_admin_request,
    > + .exit_request = nvme_rdma_exit_admin_request,
    > + .reinit_request = nvme_rdma_reinit_request,
    > + .init_hctx = nvme_rdma_init_admin_hctx,
    > + .timeout = nvme_rdma_timeout,
    > +};
    > +
    > +static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + int error;
    > +
    > + error = nvme_rdma_init_queue(ctrl, 0, NVMF_AQ_DEPTH);
    > + if (error)
    > + return error;
    > +
    > + ctrl->device = ctrl->queues[0].device;
    > +
    > + /*
    > + * We need a reference on the device as long as the tag_set is alive,
    > + * as the MRs in the request structures need a valid ib_device.
    > + */
    > + error = -EINVAL;
    > + if (!nvme_rdma_dev_get(ctrl->device))
    > + goto out_free_queue;
    > +
    > + ctrl->max_fr_pages = min_t(u32, NVME_RDMA_MAX_SEGMENTS,
    > + ctrl->device->dev->attrs.max_fast_reg_page_list_len);
    > +
    > + memset(&ctrl->admin_tag_set, 0, sizeof(ctrl->admin_tag_set));
    > + ctrl->admin_tag_set.ops = &nvme_rdma_admin_mq_ops;
    > + ctrl->admin_tag_set.queue_depth = NVME_RDMA_AQ_BLKMQ_DEPTH;
    > + ctrl->admin_tag_set.reserved_tags = 2; /* connect + keep-alive */
    > + ctrl->admin_tag_set.numa_node = NUMA_NO_NODE;
    > + ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_rdma_request) +
    > + SG_CHUNK_SIZE * sizeof(struct scatterlist);
    > + ctrl->admin_tag_set.driver_data = ctrl;
    > + ctrl->admin_tag_set.nr_hw_queues = 1;
    > + ctrl->admin_tag_set.timeout = ADMIN_TIMEOUT;
    > +
    > + error = blk_mq_alloc_tag_set(&ctrl->admin_tag_set);
    > + if (error)
    > + goto out_put_dev;
    > +
    > + ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
    > + if (IS_ERR(ctrl->ctrl.admin_q)) {
    > + error = PTR_ERR(ctrl->ctrl.admin_q);
    > + goto out_free_tagset;
    > + }
    > +
    > + error = nvmf_connect_admin_queue(&ctrl->ctrl);
    > + if (error)
    > + goto out_cleanup_queue;
    > +
    > + error = nvmf_reg_read64(&ctrl->ctrl, NVME_REG_CAP, &ctrl->cap);
    > + if (error) {
    > + dev_err(ctrl->ctrl.device,
    > + "prop_get NVME_REG_CAP failed\n");
    > + goto out_cleanup_queue;
    > + }
    > +
    > + ctrl->ctrl.sqsize =
    > + min_t(int, NVME_CAP_MQES(ctrl->cap) + 1, ctrl->ctrl.sqsize);
    > +
    > + error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap);
    > + if (error)
    > + goto out_cleanup_queue;
    > +
    > + ctrl->ctrl.max_hw_sectors =
    > + (ctrl->max_fr_pages - 1) << (PAGE_SHIFT - 9);
    > +
    > + error = nvme_init_identify(&ctrl->ctrl);
    > + if (error)
    > + goto out_cleanup_queue;
    > +
    > + nvme_start_keep_alive(&ctrl->ctrl);
    > +
    > + error = nvme_rdma_alloc_qe(ctrl->queues[0].device->dev,
    > + &ctrl->async_event_sqe, sizeof(struct nvme_command),
    > + DMA_TO_DEVICE);
    > + if (error)
    > + goto out_cleanup_queue;
    > +
    > + return 0;
    > +
    > +out_cleanup_queue:
    > + blk_cleanup_queue(ctrl->ctrl.admin_q);
    > +out_free_tagset:
    > + blk_mq_free_tag_set(&ctrl->admin_tag_set);
    > +out_put_dev:
    > + nvme_rdma_dev_put(ctrl->device);
    > +out_free_queue:
    > + nvme_rdma_free_queue(&ctrl->queues[0]);
    > + return error;
    > +}
    > +
    > +static void nvme_rdma_shutdown_ctrl(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + nvme_stop_keep_alive(&ctrl->ctrl);
    > + cancel_work_sync(&ctrl->err_work);
    > + cancel_delayed_work_sync(&ctrl->reconnect_work);
    > +
    > + if (ctrl->queue_count > 1) {
    > + nvme_stop_queues(&ctrl->ctrl);
    > + blk_mq_tagset_busy_iter(&ctrl->tag_set,
    > + nvme_cancel_request, &ctrl->ctrl);
    > + nvme_rdma_free_io_queues(ctrl);
    > + }
    > +
    > + if (ctrl->ctrl.state == NVME_CTRL_LIVE)
    > + nvme_shutdown_ctrl(&ctrl->ctrl);
    > +
    > + blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
    > + blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
    > + nvme_cancel_request, &ctrl->ctrl);
    > + nvme_rdma_destroy_admin_queue(ctrl);
    > +}
    > +
    > +static void nvme_rdma_del_ctrl_work(struct work_struct *work)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = container_of(work,
    > + struct nvme_rdma_ctrl, delete_work);
    > +
    > + nvme_remove_namespaces(&ctrl->ctrl);
    > + nvme_rdma_shutdown_ctrl(ctrl);
    > + nvme_uninit_ctrl(&ctrl->ctrl);
    > + nvme_put_ctrl(&ctrl->ctrl);
    > +}
    > +
    > +static int __nvme_rdma_del_ctrl(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING))
    > + return -EBUSY;
    > +
    > + if (!queue_work(nvme_rdma_wq, &ctrl->delete_work))
    > + return -EBUSY;
    > +
    > + return 0;
    > +}
    > +
    > +static int nvme_rdma_del_ctrl(struct nvme_ctrl *nctrl)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
    > + int ret;
    > +
    > + ret = __nvme_rdma_del_ctrl(ctrl);
    > + if (ret)
    > + return ret;
    > +
    > + flush_work(&ctrl->delete_work);
    > +
    > + return 0;
    > +}
    > +
    > +static void nvme_rdma_remove_ctrl_work(struct work_struct *work)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = container_of(work,
    > + struct nvme_rdma_ctrl, delete_work);
    > +
    > + nvme_remove_namespaces(&ctrl->ctrl);
    > + nvme_uninit_ctrl(&ctrl->ctrl);
    > + nvme_put_ctrl(&ctrl->ctrl);
    > +}
    > +
    > +static void nvme_rdma_reset_ctrl_work(struct work_struct *work)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = container_of(work,
    > + struct nvme_rdma_ctrl, reset_work);
    > + int ret;
    > + bool changed;
    > +
    > + nvme_rdma_shutdown_ctrl(ctrl);
    > +
    > + ret = nvme_rdma_configure_admin_queue(ctrl);
    > + if (ret) {
    > + /* ctrl is already shutdown, just remove the ctrl */
    > + INIT_WORK(&ctrl->delete_work, nvme_rdma_remove_ctrl_work);
    > + goto del_dead_ctrl;
    > + }
    > +
    > + if (ctrl->queue_count > 1) {
    > + ret = blk_mq_reinit_tagset(&ctrl->tag_set);
    > + if (ret)
    > + goto del_dead_ctrl;
    > +
    > + ret = nvme_rdma_init_io_queues(ctrl);
    > + if (ret)
    > + goto del_dead_ctrl;
    > +
    > + ret = nvme_rdma_connect_io_queues(ctrl);
    > + if (ret)
    > + goto del_dead_ctrl;
    > + }
    > +
    > + changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
    > + WARN_ON_ONCE(!changed);
    > +
    > + if (ctrl->queue_count > 1) {
    > + nvme_start_queues(&ctrl->ctrl);
    > + nvme_queue_scan(&ctrl->ctrl);
    > + }
    > +
    > + return;
    > +
    > +del_dead_ctrl:
    > + /* Deleting this dead controller... */
    > + dev_warn(ctrl->ctrl.device, "Removing after reset failure\n");
    > + WARN_ON(!queue_work(nvme_rdma_wq, &ctrl->delete_work));
    > +}
    > +
    > +static int nvme_rdma_reset_ctrl(struct nvme_ctrl *nctrl)
    > +{
    > + struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
    > +
    > + if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RESETTING))
    > + return -EBUSY;
    > +
    > + if (!queue_work(nvme_rdma_wq, &ctrl->reset_work))
    > + return -EBUSY;
    > +
    > + flush_work(&ctrl->reset_work);
    > +
    > + return 0;
    > +}
    > +
    > +static const struct nvme_ctrl_ops nvme_rdma_ctrl_ops = {
    > + .name = "rdma",
    > + .module = THIS_MODULE,
    > + .is_fabrics = true,
    > + .reg_read32 = nvmf_reg_read32,
    > + .reg_read64 = nvmf_reg_read64,
    > + .reg_write32 = nvmf_reg_write32,
    > + .reset_ctrl = nvme_rdma_reset_ctrl,
    > + .free_ctrl = nvme_rdma_free_ctrl,
    > + .submit_async_event = nvme_rdma_submit_async_event,
    > + .delete_ctrl = nvme_rdma_del_ctrl,
    > + .get_subsysnqn = nvmf_get_subsysnqn,
    > + .get_address = nvmf_get_address,
    > +};
    > +
    > +static int nvme_rdma_create_io_queues(struct nvme_rdma_ctrl *ctrl)
    > +{
    > + struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
    > + int ret;
    > +
    > + ret = nvme_set_queue_count(&ctrl->ctrl, &opts->nr_io_queues);
    > + if (ret)
    > + return ret;
    > +
    > + ctrl->queue_count = opts->nr_io_queues + 1;
    > + if (ctrl->queue_count < 2)
    > + return 0;
    > +
    > + dev_info(ctrl->ctrl.device,
    > + "creating %d I/O queues.\n", opts->nr_io_queues);
    > +
    > + ret = nvme_rdma_init_io_queues(ctrl);
    > + if (ret)
    > + return ret;
    > +
    > + /*
    > + * We need a reference on the device as long as the tag_set is alive,
    > + * as the MRs in the request structures need a valid ib_device.
    > + */
    > + ret = -EINVAL;
    > + if (!nvme_rdma_dev_get(ctrl->device))
    > + goto out_free_io_queues;
    > +
    > + memset(&ctrl->tag_set, 0, sizeof(ctrl->tag_set));
    > + ctrl->tag_set.ops = &nvme_rdma_mq_ops;
    > + ctrl->tag_set.queue_depth = ctrl->ctrl.sqsize;
    > + ctrl->tag_set.reserved_tags = 1; /* fabric connect */
    > + ctrl->tag_set.numa_node = NUMA_NO_NODE;
    > + ctrl->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
    > + ctrl->tag_set.cmd_size = sizeof(struct nvme_rdma_request) +
    > + SG_CHUNK_SIZE * sizeof(struct scatterlist);
    > + ctrl->tag_set.driver_data = ctrl;
    > + ctrl->tag_set.nr_hw_queues = ctrl->queue_count - 1;
    > + ctrl->tag_set.timeout = NVME_IO_TIMEOUT;
    > +
    > + ret = blk_mq_alloc_tag_set(&ctrl->tag_set);
    > + if (ret)
    > + goto out_put_dev;
    > + ctrl->ctrl.tagset = &ctrl->tag_set;
    > +
    > + ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set);
    > + if (IS_ERR(ctrl->ctrl.connect_q)) {
    > + ret = PTR_ERR(ctrl->ctrl.connect_q);
    > + goto out_free_tag_set;
    > + }
    > +
    > + ret = nvme_rdma_connect_io_queues(ctrl);
    > + if (ret)
    > + goto out_cleanup_connect_q;
    > +
    > + return 0;
    > +
    > +out_cleanup_connect_q:
    > + nvme_stop_keep_alive(&ctrl->ctrl);
    > + blk_cleanup_queue(ctrl->ctrl.connect_q);
    > +out_free_tag_set:
    > + blk_mq_free_tag_set(&ctrl->tag_set);
    > +out_put_dev:
    > + nvme_rdma_dev_put(ctrl->device);
    > +out_free_io_queues:
    > + nvme_rdma_free_io_queues(ctrl);
    > + return ret;
    > +}
    > +
    > +static int nvme_rdma_parse_ipaddr(struct sockaddr_in *in_addr, char *p)
    > +{
    > + u8 *addr = (u8 *)&in_addr->sin_addr.s_addr;
    > + size_t buflen = strlen(p);
    > +
    > + /* XXX: handle IPv6 addresses */
    > +
    > + if (buflen > INET_ADDRSTRLEN)
    > + return -EINVAL;
    > + if (in4_pton(p, buflen, addr, '\0', NULL) == 0)
    > + return -EINVAL;
    > + in_addr->sin_family = AF_INET;
    > + return 0;
    > +}
    > +
    > +static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
    > + struct nvmf_ctrl_options *opts)
    > +{
    > + struct nvme_rdma_ctrl *ctrl;
    > + int ret;
    > + bool changed;
    > +
    > + ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
    > + if (!ctrl)
    > + return ERR_PTR(-ENOMEM);
    > + ctrl->ctrl.opts = opts;
    > + INIT_LIST_HEAD(&ctrl->list);
    > +
    > + ret = nvme_rdma_parse_ipaddr(&ctrl->addr_in, opts->traddr);
    > + if (ret) {
    > + pr_err("malformed IP address passed: %s\n", opts->traddr);
    > + goto out_free_ctrl;
    > + }
    > +
    > + if (opts->mask & NVMF_OPT_TRSVCID) {
    > + u16 port;
    > +
    > + ret = kstrtou16(opts->trsvcid, 0, &port);
    > + if (ret)
    > + goto out_free_ctrl;
    > +
    > + ctrl->addr_in.sin_port = cpu_to_be16(port);
    > + } else {
    > + ctrl->addr_in.sin_port = cpu_to_be16(NVME_RDMA_IP_PORT);
    > + }
    > +
    > + ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_rdma_ctrl_ops,
    > + 0 /* no quirks, we're perfect! */);
    > + if (ret)
    > + goto out_free_ctrl;
    > +
    > + ctrl->reconnect_delay = opts->reconnect_delay;
    > + INIT_DELAYED_WORK(&ctrl->reconnect_work,
    > + nvme_rdma_reconnect_ctrl_work);
    > + INIT_WORK(&ctrl->err_work, nvme_rdma_error_recovery_work);
    > + INIT_WORK(&ctrl->delete_work, nvme_rdma_del_ctrl_work);
    > + INIT_WORK(&ctrl->reset_work, nvme_rdma_reset_ctrl_work);
    > + spin_lock_init(&ctrl->lock);
    > +
    > + ctrl->queue_count = opts->nr_io_queues + 1; /* +1 for admin queue */
    > + ctrl->ctrl.sqsize = opts->queue_size;
    > + ctrl->tl_retry_count = opts->tl_retry_count;
    > + ctrl->ctrl.kato = opts->kato;
    > +
    > + ret = -ENOMEM;
    > + ctrl->queues = kcalloc(ctrl->queue_count, sizeof(*ctrl->queues),
    > + GFP_KERNEL);
    > + if (!ctrl->queues)
    > + goto out_uninit_ctrl;
    > +
    > + ret = nvme_rdma_configure_admin_queue(ctrl);
    > + if (ret)
    > + goto out_kfree_queues;
    > +
    > + /* sanity check icdoff */
    > + if (ctrl->ctrl.icdoff) {
    > + dev_err(ctrl->ctrl.device, "icdoff is not supported!\n");
    > + goto out_remove_admin_queue;
    > + }
    > +
    > + /* sanity check keyed sgls */
    > + if (!(ctrl->ctrl.sgls & (1 << 20))) {
    > + dev_err(ctrl->ctrl.device, "Mandatory keyed sgls are not support\n");
    > + goto out_remove_admin_queue;
    > + }
    > +
    > + 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;
    > + }
    > +
    > + if (opts->nr_io_queues) {
    > + ret = nvme_rdma_create_io_queues(ctrl);
    > + if (ret)
    > + goto out_remove_admin_queue;
    > + }
    > +
    > + changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
    > + WARN_ON_ONCE(!changed);
    > +
    > + dev_info(ctrl->ctrl.device, "new ctrl: NQN \"%s\", addr %pISp\n",
    > + ctrl->ctrl.opts->subsysnqn, &ctrl->addr);
    > +
    > + kref_get(&ctrl->ctrl.kref);
    > +
    > + mutex_lock(&nvme_rdma_ctrl_mutex);
    > + list_add_tail(&ctrl->list, &nvme_rdma_ctrl_list);
    > + mutex_unlock(&nvme_rdma_ctrl_mutex);
    > +
    > + if (opts->nr_io_queues) {
    > + nvme_queue_scan(&ctrl->ctrl);
    > + nvme_queue_async_events(&ctrl->ctrl);
    > + }
    > +
    > + return &ctrl->ctrl;
    > +
    > +out_remove_admin_queue:
    > + nvme_rdma_destroy_admin_queue(ctrl);
    > +out_kfree_queues:
    > + kfree(ctrl->queues);
    > +out_uninit_ctrl:
    > + nvme_uninit_ctrl(&ctrl->ctrl);
    > + nvme_put_ctrl(&ctrl->ctrl);
    > + if (ret > 0)
    > + ret = -EIO;
    > + return ERR_PTR(ret);
    > +out_free_ctrl:
    > + kfree(ctrl);
    > + return ERR_PTR(ret);
    > +}
    > +
    > +static struct nvmf_transport_ops nvme_rdma_transport = {
    > + .name = "rdma",
    > + .required_opts = NVMF_OPT_TRADDR,
    > + .allowed_opts = NVMF_OPT_TRSVCID | NVMF_OPT_TL_RETRY_COUNT |
    > + NVMF_OPT_RECONNECT_DELAY,
    > + .create_ctrl = nvme_rdma_create_ctrl,
    > +};
    > +
    > +static int __init nvme_rdma_init_module(void)
    > +{
    > + nvme_rdma_wq = create_workqueue("nvme_rdma_wq");
    > + if (!nvme_rdma_wq)
    > + return -ENOMEM;
    > +
    > + nvmf_register_transport(&nvme_rdma_transport);
    > + return 0;
    > +}
    > +
    > +static void __exit nvme_rdma_cleanup_module(void)
    > +{
    > + struct nvme_rdma_ctrl *ctrl;
    > +
    > + nvmf_unregister_transport(&nvme_rdma_transport);
    > +
    > + mutex_lock(&nvme_rdma_ctrl_mutex);
    > + list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list)
    > + __nvme_rdma_del_ctrl(ctrl);
    > + mutex_unlock(&nvme_rdma_ctrl_mutex);
    > +
    > + destroy_workqueue(nvme_rdma_wq);
    > +}
    > +
    > +module_init(nvme_rdma_init_module);
    > +module_exit(nvme_rdma_cleanup_module);
    > +
    > +MODULE_LICENSE("GPL v2");
    >

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      Last update: 2016-06-07 14:21    [W:3.375 / U:0.024 seconds]
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