drivers/nvme/host/rdma.c

   1 /*
   2  * NVMe over Fabrics RDMA host code.
   3  * Copyright (c) 2015-2016 HGST, a Western Digital Company.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  */
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/err.h>
  19 #include <linux/string.h>
  20 #include <linux/atomic.h>
  21 #include <linux/blk-mq.h>
  22 #include <linux/blk-mq-rdma.h>
  23 #include <linux/types.h>
  24 #include <linux/list.h>
  25 #include <linux/mutex.h>
  26 #include <linux/scatterlist.h>
  27 #include <linux/nvme.h>
  28 #include <asm/unaligned.h>
  29
  30 #include <rdma/ib_verbs.h>
  31 #include <rdma/rdma_cm.h>
  32 #include <linux/nvme-rdma.h>
  33
  34 #include "nvme.h"
  35 #include "fabrics.h"
  36
  37
  38 #define NVME_RDMA_CONNECT_TIMEOUT_MS    3000            /* 3 second */
  39
  40 #define NVME_RDMA_MAX_SEGMENTS          256
  41
  42 #define NVME_RDMA_MAX_INLINE_SEGMENTS   1
  43
  44 /*
  45  * We handle AEN commands ourselves and don't even let the
  46  * block layer know about them.
  47  */
  48 #define NVME_RDMA_NR_AEN_COMMANDS      1
  49 #define NVME_RDMA_AQ_BLKMQ_DEPTH       \
  50         (NVME_AQ_DEPTH - NVME_RDMA_NR_AEN_COMMANDS)
  51
  52 struct nvme_rdma_device {
  53         struct ib_device       *dev;
  54         struct ib_pd           *pd;
  55         struct kref             ref;
  56         struct list_head        entry;
  57 };
  58
  59 struct nvme_rdma_qe {
  60         struct ib_cqe           cqe;
  61         void                    *data;
  62         u64                     dma;
  63 };
  64
  65 struct nvme_rdma_queue;
  66 struct nvme_rdma_request {
  67         struct nvme_request     req;
  68         struct ib_mr            *mr;
  69         struct nvme_rdma_qe     sqe;
  70         struct ib_sge           sge[1 + NVME_RDMA_MAX_INLINE_SEGMENTS];
  71         u32                     num_sge;
  72         int                     nents;
  73         bool                    inline_data;
  74         struct ib_reg_wr        reg_wr;
  75         struct ib_cqe           reg_cqe;
  76         struct nvme_rdma_queue  *queue;
  77         struct sg_table         sg_table;
  78         struct scatterlist      first_sgl[];
  79 };
  80
  81 enum nvme_rdma_queue_flags {
  82         NVME_RDMA_Q_LIVE                = 0,
  83         NVME_RDMA_Q_DELETING            = 1,
  84 };
  85
  86 struct nvme_rdma_queue {
  87         struct nvme_rdma_qe     *rsp_ring;
  88         atomic_t                sig_count;
  89         int                     queue_size;
  90         size_t                  cmnd_capsule_len;
  91         struct nvme_rdma_ctrl   *ctrl;
  92         struct nvme_rdma_device *device;
  93         struct ib_cq            *ib_cq;
  94         struct ib_qp            *qp;
  95
  96         unsigned long           flags;
  97         struct rdma_cm_id       *cm_id;
  98         int                     cm_error;
  99         struct completion       cm_done;
 100 };
 101
 102 struct nvme_rdma_ctrl {
 103         /* read only in the hot path */
 104         struct nvme_rdma_queue  *queues;
 105
 106         /* other member variables */
 107         struct blk_mq_tag_set   tag_set;
 108         struct work_struct      delete_work;
 109         struct work_struct      err_work;
 110
 111         struct nvme_rdma_qe     async_event_sqe;
 112
 113         struct delayed_work     reconnect_work;
 114
 115         struct list_head        list;
 116
 117         struct blk_mq_tag_set   admin_tag_set;
 118         struct nvme_rdma_device *device;
 119
 120         u32                     max_fr_pages;
 121
 122         struct sockaddr_storage addr;
 123         struct sockaddr_storage src_addr;
 124
 125         struct nvme_ctrl        ctrl;
 126 };
 127
 128 static inline struct nvme_rdma_ctrl *to_rdma_ctrl(struct nvme_ctrl *ctrl)
 129 {
 130         return container_of(ctrl, struct nvme_rdma_ctrl, ctrl);
 131 }
 132
 133 static LIST_HEAD(device_list);
 134 static DEFINE_MUTEX(device_list_mutex);
 135
 136 static LIST_HEAD(nvme_rdma_ctrl_list);
 137 static DEFINE_MUTEX(nvme_rdma_ctrl_mutex);
 138
 139 /*
 140  * Disabling this option makes small I/O goes faster, but is fundamentally
 141  * unsafe.  With it turned off we will have to register a global rkey that
 142  * allows read and write access to all physical memory.
 143  */
 144 static bool register_always = true;
 145 module_param(register_always, bool, 0444);
 146 MODULE_PARM_DESC(register_always,
 147          "Use memory registration even for contiguous memory regions");
 148
 149 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
 150                 struct rdma_cm_event *event);
 151 static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
 152
 153 static const struct blk_mq_ops nvme_rdma_mq_ops;
 154 static const struct blk_mq_ops nvme_rdma_admin_mq_ops;
 155
 156 /* XXX: really should move to a generic header sooner or later.. */
 157 static inline void put_unaligned_le24(u32 val, u8 *p)
 158 {
 159         *p++ = val;
 160         *p++ = val >> 8;
 161         *p++ = val >> 16;
 162 }
 163
 164 static inline int nvme_rdma_queue_idx(struct nvme_rdma_queue *queue)
 165 {
 166         return queue - queue->ctrl->queues;
 167 }
 168
 169 static inline size_t nvme_rdma_inline_data_size(struct nvme_rdma_queue *queue)
 170 {
 171         return queue->cmnd_capsule_len - sizeof(struct nvme_command);
 172 }
 173
 174 static void nvme_rdma_free_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
 175                 size_t capsule_size, enum dma_data_direction dir)
 176 {
 177         ib_dma_unmap_single(ibdev, qe->dma, capsule_size, dir);
 178         kfree(qe->data);
 179 }
 180
 181 static int nvme_rdma_alloc_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
 182                 size_t capsule_size, enum dma_data_direction dir)
 183 {
 184         qe->data = kzalloc(capsule_size, GFP_KERNEL);
 185         if (!qe->data)
 186                 return -ENOMEM;
 187
 188         qe->dma = ib_dma_map_single(ibdev, qe->data, capsule_size, dir);
 189         if (ib_dma_mapping_error(ibdev, qe->dma)) {
 190                 kfree(qe->data);
 191                 return -ENOMEM;
 192         }
 193
 194         return 0;
 195 }
 196
 197 static void nvme_rdma_free_ring(struct ib_device *ibdev,
 198                 struct nvme_rdma_qe *ring, size_t ib_queue_size,
 199                 size_t capsule_size, enum dma_data_direction dir)
 200 {
 201         int i;
 202
 203         for (i = 0; i < ib_queue_size; i++)
 204                 nvme_rdma_free_qe(ibdev, &ring[i], capsule_size, dir);
 205         kfree(ring);
 206 }
 207
 208 static struct nvme_rdma_qe *nvme_rdma_alloc_ring(struct ib_device *ibdev,
 209                 size_t ib_queue_size, size_t capsule_size,
 210                 enum dma_data_direction dir)
 211 {
 212         struct nvme_rdma_qe *ring;
 213         int i;
 214
 215         ring = kcalloc(ib_queue_size, sizeof(struct nvme_rdma_qe), GFP_KERNEL);
 216         if (!ring)
 217                 return NULL;
 218
 219         for (i = 0; i < ib_queue_size; i++) {
 220                 if (nvme_rdma_alloc_qe(ibdev, &ring[i], capsule_size, dir))
 221                         goto out_free_ring;
 222         }
 223
 224         return ring;
 225
 226 out_free_ring:
 227         nvme_rdma_free_ring(ibdev, ring, i, capsule_size, dir);
 228         return NULL;
 229 }
 230
 231 static void nvme_rdma_qp_event(struct ib_event *event, void *context)
 232 {
 233         pr_debug("QP event %s (%d)\n",
 234                  ib_event_msg(event->event), event->event);
 235
 236 }
 237
 238 static int nvme_rdma_wait_for_cm(struct nvme_rdma_queue *queue)
 239 {
 240         wait_for_completion_interruptible_timeout(&queue->cm_done,
 241                         msecs_to_jiffies(NVME_RDMA_CONNECT_TIMEOUT_MS) + 1);
 242         return queue->cm_error;
 243 }
 244
 245 static int nvme_rdma_create_qp(struct nvme_rdma_queue *queue, const int factor)
 246 {
 247         struct nvme_rdma_device *dev = queue->device;
 248         struct ib_qp_init_attr init_attr;
 249         int ret;
 250
 251         memset(&init_attr, 0, sizeof(init_attr));
 252         init_attr.event_handler = nvme_rdma_qp_event;
 253         /* +1 for drain */
 254         init_attr.cap.max_send_wr = factor * queue->queue_size + 1;
 255         /* +1 for drain */
 256         init_attr.cap.max_recv_wr = queue->queue_size + 1;
 257         init_attr.cap.max_recv_sge = 1;
 258         init_attr.cap.max_send_sge = 1 + NVME_RDMA_MAX_INLINE_SEGMENTS;
 259         init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
 260         init_attr.qp_type = IB_QPT_RC;
 261         init_attr.send_cq = queue->ib_cq;
 262         init_attr.recv_cq = queue->ib_cq;
 263
 264         ret = rdma_create_qp(queue->cm_id, dev->pd, &init_attr);
 265
 266         queue->qp = queue->cm_id->qp;
 267         return ret;
 268 }
 269
 270 static int nvme_rdma_reinit_request(void *data, struct request *rq)
 271 {
 272         struct nvme_rdma_ctrl *ctrl = data;
 273         struct nvme_rdma_device *dev = ctrl->device;
 274         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
 275         int ret = 0;
 276
 277         ib_dereg_mr(req->mr);
 278
 279         req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,
 280                         ctrl->max_fr_pages);
 281         if (IS_ERR(req->mr)) {
 282                 ret = PTR_ERR(req->mr);
 283                 req->mr = NULL;
 284                 goto out;
 285         }
 286
 287         req->mr->need_inval = false;
 288
 289 out:
 290         return ret;
 291 }
 292
 293 static void nvme_rdma_exit_request(struct blk_mq_tag_set *set,
 294                 struct request *rq, unsigned int hctx_idx)
 295 {
 296         struct nvme_rdma_ctrl *ctrl = set->driver_data;
 297         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
 298         int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
 299         struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
 300         struct nvme_rdma_device *dev = queue->device;
 301
 302         if (req->mr)
 303                 ib_dereg_mr(req->mr);
 304
 305         nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
 306                         DMA_TO_DEVICE);
 307 }
 308
 309 static int nvme_rdma_init_request(struct blk_mq_tag_set *set,
 310                 struct request *rq, unsigned int hctx_idx,
 311                 unsigned int numa_node)
 312 {
 313         struct nvme_rdma_ctrl *ctrl = set->driver_data;
 314         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
 315         int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
 316         struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
 317         struct nvme_rdma_device *dev = queue->device;
 318         struct ib_device *ibdev = dev->dev;
 319         int ret;
 320
 321         ret = nvme_rdma_alloc_qe(ibdev, &req->sqe, sizeof(struct nvme_command),
 322                         DMA_TO_DEVICE);
 323         if (ret)
 324                 return ret;
 325
 326         req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,
 327                         ctrl->max_fr_pages);
 328         if (IS_ERR(req->mr)) {
 329                 ret = PTR_ERR(req->mr);
 330                 goto out_free_qe;
 331         }
 332
 333         req->queue = queue;
 334
 335         return 0;
 336
 337 out_free_qe:
 338         nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
 339                         DMA_TO_DEVICE);
 340         return -ENOMEM;
 341 }
 342
 343 static int nvme_rdma_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
 344                 unsigned int hctx_idx)
 345 {
 346         struct nvme_rdma_ctrl *ctrl = data;
 347         struct nvme_rdma_queue *queue = &ctrl->queues[hctx_idx + 1];
 348
 349         BUG_ON(hctx_idx >= ctrl->ctrl.queue_count);
 350
 351         hctx->driver_data = queue;
 352         return 0;
 353 }
 354
 355 static int nvme_rdma_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
 356                 unsigned int hctx_idx)
 357 {
 358         struct nvme_rdma_ctrl *ctrl = data;
 359         struct nvme_rdma_queue *queue = &ctrl->queues[0];
 360
 361         BUG_ON(hctx_idx != 0);
 362
 363         hctx->driver_data = queue;
 364         return 0;
 365 }
 366
 367 static void nvme_rdma_free_dev(struct kref *ref)
 368 {
 369         struct nvme_rdma_device *ndev =
 370                 container_of(ref, struct nvme_rdma_device, ref);
 371
 372         mutex_lock(&device_list_mutex);
 373         list_del(&ndev->entry);
 374         mutex_unlock(&device_list_mutex);
 375
 376         ib_dealloc_pd(ndev->pd);
 377         kfree(ndev);
 378 }
 379
 380 static void nvme_rdma_dev_put(struct nvme_rdma_device *dev)
 381 {
 382         kref_put(&dev->ref, nvme_rdma_free_dev);
 383 }
 384
 385 static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
 386 {
 387         return kref_get_unless_zero(&dev->ref);
 388 }
 389
 390 static struct nvme_rdma_device *
 391 nvme_rdma_find_get_device(struct rdma_cm_id *cm_id)
 392 {
 393         struct nvme_rdma_device *ndev;
 394
 395         mutex_lock(&device_list_mutex);
 396         list_for_each_entry(ndev, &device_list, entry) {
 397                 if (ndev->dev->node_guid == cm_id->device->node_guid &&
 398                     nvme_rdma_dev_get(ndev))
 399                         goto out_unlock;
 400         }
 401
 402         ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
 403         if (!ndev)
 404                 goto out_err;
 405
 406         ndev->dev = cm_id->device;
 407         kref_init(&ndev->ref);
 408
 409         ndev->pd = ib_alloc_pd(ndev->dev,
 410                 register_always ? 0 : IB_PD_UNSAFE_GLOBAL_RKEY);
 411         if (IS_ERR(ndev->pd))
 412                 goto out_free_dev;
 413
 414         if (!(ndev->dev->attrs.device_cap_flags &
 415               IB_DEVICE_MEM_MGT_EXTENSIONS)) {
 416                 dev_err(&ndev->dev->dev,
 417                         "Memory registrations not supported.\n");
 418                 goto out_free_pd;
 419         }
 420
 421         list_add(&ndev->entry, &device_list);
 422 out_unlock:
 423         mutex_unlock(&device_list_mutex);
 424         return ndev;
 425
 426 out_free_pd:
 427         ib_dealloc_pd(ndev->pd);
 428 out_free_dev:
 429         kfree(ndev);
 430 out_err:
 431         mutex_unlock(&device_list_mutex);
 432         return NULL;
 433 }
 434
 435 static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue)
 436 {
 437         struct nvme_rdma_device *dev;
 438         struct ib_device *ibdev;
 439
 440         dev = queue->device;
 441         ibdev = dev->dev;
 442         rdma_destroy_qp(queue->cm_id);
 443         ib_free_cq(queue->ib_cq);
 444
 445         nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
 446                         sizeof(struct nvme_completion), DMA_FROM_DEVICE);
 447
 448         nvme_rdma_dev_put(dev);
 449 }
 450
 451 static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue)
 452 {
 453         struct ib_device *ibdev;
 454         const int send_wr_factor = 3;                   /* MR, SEND, INV */
 455         const int cq_factor = send_wr_factor + 1;       /* + RECV */
 456         int comp_vector, idx = nvme_rdma_queue_idx(queue);
 457         int ret;
 458
 459         queue->device = nvme_rdma_find_get_device(queue->cm_id);
 460         if (!queue->device) {
 461                 dev_err(queue->cm_id->device->dev.parent,
 462                         "no client data found!\n");
 463                 return -ECONNREFUSED;
 464         }
 465         ibdev = queue->device->dev;
 466
 467         /*
 468          * Spread I/O queues completion vectors according their queue index.
 469          * Admin queues can always go on completion vector 0.
 470          */
 471         comp_vector = idx == 0 ? idx : idx - 1;
 472
 473         /* +1 for ib_stop_cq */
 474         queue->ib_cq = ib_alloc_cq(ibdev, queue,
 475                                 cq_factor * queue->queue_size + 1,
 476                                 comp_vector, IB_POLL_SOFTIRQ);
 477         if (IS_ERR(queue->ib_cq)) {
 478                 ret = PTR_ERR(queue->ib_cq);
 479                 goto out_put_dev;
 480         }
 481
 482         ret = nvme_rdma_create_qp(queue, send_wr_factor);
 483         if (ret)
 484                 goto out_destroy_ib_cq;
 485
 486         queue->rsp_ring = nvme_rdma_alloc_ring(ibdev, queue->queue_size,
 487                         sizeof(struct nvme_completion), DMA_FROM_DEVICE);
 488         if (!queue->rsp_ring) {
 489                 ret = -ENOMEM;
 490                 goto out_destroy_qp;
 491         }
 492
 493         return 0;
 494
 495 out_destroy_qp:
 496         ib_destroy_qp(queue->qp);
 497 out_destroy_ib_cq:
 498         ib_free_cq(queue->ib_cq);
 499 out_put_dev:
 500         nvme_rdma_dev_put(queue->device);
 501         return ret;
 502 }
 503
 504 static int nvme_rdma_alloc_queue(struct nvme_rdma_ctrl *ctrl,
 505                 int idx, size_t queue_size)
 506 {
 507         struct nvme_rdma_queue *queue;
 508         struct sockaddr *src_addr = NULL;
 509         int ret;
 510
 511         queue = &ctrl->queues[idx];
 512         queue->ctrl = ctrl;
 513         init_completion(&queue->cm_done);
 514
 515         if (idx > 0)
 516                 queue->cmnd_capsule_len = ctrl->ctrl.ioccsz * 16;
 517         else
 518                 queue->cmnd_capsule_len = sizeof(struct nvme_command);
 519
 520         queue->queue_size = queue_size;
 521         atomic_set(&queue->sig_count, 0);
 522
 523         queue->cm_id = rdma_create_id(&init_net, nvme_rdma_cm_handler, queue,
 524                         RDMA_PS_TCP, IB_QPT_RC);
 525         if (IS_ERR(queue->cm_id)) {
 526                 dev_info(ctrl->ctrl.device,
 527                         "failed to create CM ID: %ld\n", PTR_ERR(queue->cm_id));
 528                 return PTR_ERR(queue->cm_id);
 529         }
 530
 531         if (ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR)
 532                 src_addr = (struct sockaddr *)&ctrl->src_addr;
 533
 534         queue->cm_error = -ETIMEDOUT;
 535         ret = rdma_resolve_addr(queue->cm_id, src_addr,
 536                         (struct sockaddr *)&ctrl->addr,
 537                         NVME_RDMA_CONNECT_TIMEOUT_MS);
 538         if (ret) {
 539                 dev_info(ctrl->ctrl.device,
 540                         "rdma_resolve_addr failed (%d).\n", ret);
 541                 goto out_destroy_cm_id;
 542         }
 543
 544         ret = nvme_rdma_wait_for_cm(queue);
 545         if (ret) {
 546                 dev_info(ctrl->ctrl.device,
 547                         "rdma_resolve_addr wait failed (%d).\n", ret);
 548                 goto out_destroy_cm_id;
 549         }
 550
 551         clear_bit(NVME_RDMA_Q_DELETING, &queue->flags);
 552
 553         return 0;
 554
 555 out_destroy_cm_id:
 556         rdma_destroy_id(queue->cm_id);
 557         return ret;
 558 }
 559
 560 static void nvme_rdma_stop_queue(struct nvme_rdma_queue *queue)
 561 {
 562         if (!test_and_clear_bit(NVME_RDMA_Q_LIVE, &queue->flags))
 563                 return;
 564
 565         rdma_disconnect(queue->cm_id);
 566         ib_drain_qp(queue->qp);
 567 }
 568
 569 static void nvme_rdma_free_queue(struct nvme_rdma_queue *queue)
 570 {
 571         if (test_and_set_bit(NVME_RDMA_Q_DELETING, &queue->flags))
 572                 return;
 573
 574         nvme_rdma_destroy_queue_ib(queue);
 575         rdma_destroy_id(queue->cm_id);
 576 }
 577
 578 static void nvme_rdma_free_io_queues(struct nvme_rdma_ctrl *ctrl)
 579 {
 580         int i;
 581
 582         for (i = 1; i < ctrl->ctrl.queue_count; i++)
 583                 nvme_rdma_free_queue(&ctrl->queues[i]);
 584 }
 585
 586 static void nvme_rdma_stop_io_queues(struct nvme_rdma_ctrl *ctrl)
 587 {
 588         int i;
 589
 590         for (i = 1; i < ctrl->ctrl.queue_count; i++)
 591                 nvme_rdma_stop_queue(&ctrl->queues[i]);
 592 }
 593
 594 static int nvme_rdma_start_queue(struct nvme_rdma_ctrl *ctrl, int idx)
 595 {
 596         int ret;
 597
 598         if (idx)
 599                 ret = nvmf_connect_io_queue(&ctrl->ctrl, idx);
 600         else
 601                 ret = nvmf_connect_admin_queue(&ctrl->ctrl);
 602
 603         if (!ret)
 604                 set_bit(NVME_RDMA_Q_LIVE, &ctrl->queues[idx].flags);
 605         else
 606                 dev_info(ctrl->ctrl.device,
 607                         "failed to connect queue: %d ret=%d\n", idx, ret);
 608         return ret;
 609 }
 610
 611 static int nvme_rdma_start_io_queues(struct nvme_rdma_ctrl *ctrl)
 612 {
 613         int i, ret = 0;
 614
 615         for (i = 1; i < ctrl->ctrl.queue_count; i++) {
 616                 ret = nvme_rdma_start_queue(ctrl, i);
 617                 if (ret)
 618                         goto out_stop_queues;
 619         }
 620
 621         return 0;
 622
 623 out_stop_queues:
 624         for (i--; i >= 1; i--)
 625                 nvme_rdma_stop_queue(&ctrl->queues[i]);
 626         return ret;
 627 }
 628
 629 static int nvme_rdma_alloc_io_queues(struct nvme_rdma_ctrl *ctrl)
 630 {
 631         struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
 632         struct ib_device *ibdev = ctrl->device->dev;
 633         unsigned int nr_io_queues;
 634         int i, ret;
 635
 636         nr_io_queues = min(opts->nr_io_queues, num_online_cpus());
 637
 638         /*
 639          * we map queues according to the device irq vectors for
 640          * optimal locality so we don't need more queues than
 641          * completion vectors.
 642          */
 643         nr_io_queues = min_t(unsigned int, nr_io_queues,
 644                                 ibdev->num_comp_vectors);
 645
 646         ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
 647         if (ret)
 648                 return ret;
 649
 650         ctrl->ctrl.queue_count = nr_io_queues + 1;
 651         if (ctrl->ctrl.queue_count < 2)
 652                 return 0;
 653
 654         dev_info(ctrl->ctrl.device,
 655                 "creating %d I/O queues.\n", nr_io_queues);
 656
 657         for (i = 1; i < ctrl->ctrl.queue_count; i++) {
 658                 ret = nvme_rdma_alloc_queue(ctrl, i,
 659                                 ctrl->ctrl.sqsize + 1);
 660                 if (ret)
 661                         goto out_free_queues;
 662         }
 663
 664         return 0;
 665
 666 out_free_queues:
 667         for (i--; i >= 1; i--)
 668                 nvme_rdma_free_queue(&ctrl->queues[i]);
 669
 670         return ret;
 671 }
 672
 673 static void nvme_rdma_free_tagset(struct nvme_ctrl *nctrl, bool admin)
 674 {
 675         struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
 676         struct blk_mq_tag_set *set = admin ?
 677                         &ctrl->admin_tag_set : &ctrl->tag_set;
 678
 679         blk_mq_free_tag_set(set);
 680         nvme_rdma_dev_put(ctrl->device);
 681 }
 682
 683 static struct blk_mq_tag_set *nvme_rdma_alloc_tagset(struct nvme_ctrl *nctrl,
 684                 bool admin)
 685 {
 686         struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
 687         struct blk_mq_tag_set *set;
 688         int ret;
 689
 690         if (admin) {
 691                 set = &ctrl->admin_tag_set;
 692                 memset(set, 0, sizeof(*set));
 693                 set->ops = &nvme_rdma_admin_mq_ops;
 694                 set->queue_depth = NVME_RDMA_AQ_BLKMQ_DEPTH;
 695                 set->reserved_tags = 2; /* connect + keep-alive */
 696                 set->numa_node = NUMA_NO_NODE;
 697                 set->cmd_size = sizeof(struct nvme_rdma_request) +
 698                         SG_CHUNK_SIZE * sizeof(struct scatterlist);
 699                 set->driver_data = ctrl;
 700                 set->nr_hw_queues = 1;
 701                 set->timeout = ADMIN_TIMEOUT;
 702         } else {
 703                 set = &ctrl->tag_set;
 704                 memset(set, 0, sizeof(*set));
 705                 set->ops = &nvme_rdma_mq_ops;
 706                 set->queue_depth = nctrl->opts->queue_size;
 707                 set->reserved_tags = 1; /* fabric connect */
 708                 set->numa_node = NUMA_NO_NODE;
 709                 set->flags = BLK_MQ_F_SHOULD_MERGE;
 710                 set->cmd_size = sizeof(struct nvme_rdma_request) +
 711                         SG_CHUNK_SIZE * sizeof(struct scatterlist);
 712                 set->driver_data = ctrl;
 713                 set->nr_hw_queues = nctrl->queue_count - 1;
 714                 set->timeout = NVME_IO_TIMEOUT;
 715         }
 716
 717         ret = blk_mq_alloc_tag_set(set);
 718         if (ret)
 719                 goto out;
 720
 721         /*
 722          * We need a reference on the device as long as the tag_set is alive,
 723          * as the MRs in the request structures need a valid ib_device.
 724          */
 725         ret = nvme_rdma_dev_get(ctrl->device);
 726         if (!ret) {
 727                 ret = -EINVAL;
 728                 goto out_free_tagset;
 729         }
 730
 731         return set;
 732
 733 out_free_tagset:
 734         blk_mq_free_tag_set(set);
 735 out:
 736         return ERR_PTR(ret);
 737 }
 738
 739 static void nvme_rdma_destroy_admin_queue(struct nvme_rdma_ctrl *ctrl,
 740                 bool remove)
 741 {
 742         nvme_rdma_free_qe(ctrl->queues[0].device->dev, &ctrl->async_event_sqe,
 743                         sizeof(struct nvme_command), DMA_TO_DEVICE);
 744         nvme_rdma_stop_queue(&ctrl->queues[0]);
 745         if (remove) {
 746                 blk_cleanup_queue(ctrl->ctrl.admin_q);
 747                 nvme_rdma_free_tagset(&ctrl->ctrl, true);
 748         }
 749         nvme_rdma_free_queue(&ctrl->queues[0]);
 750 }
 751
 752 static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl,
 753                 bool new)
 754 {
 755         int error;
 756
 757         error = nvme_rdma_alloc_queue(ctrl, 0, NVME_AQ_DEPTH);
 758         if (error)
 759                 return error;
 760
 761         ctrl->device = ctrl->queues[0].device;
 762
 763         ctrl->max_fr_pages = min_t(u32, NVME_RDMA_MAX_SEGMENTS,
 764                 ctrl->device->dev->attrs.max_fast_reg_page_list_len);
 765
 766         if (new) {
 767                 ctrl->ctrl.admin_tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, true);
 768                 if (IS_ERR(ctrl->ctrl.admin_tagset))
 769                         goto out_free_queue;
 770
 771                 ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
 772                 if (IS_ERR(ctrl->ctrl.admin_q)) {
 773                         error = PTR_ERR(ctrl->ctrl.admin_q);
 774                         goto out_free_tagset;
 775                 }
 776         } else {
 777                 error = blk_mq_reinit_tagset(&ctrl->admin_tag_set,
 778                                              nvme_rdma_reinit_request);
 779                 if (error)
 780                         goto out_free_queue;
 781         }
 782
 783         error = nvme_rdma_start_queue(ctrl, 0);
 784         if (error)
 785                 goto out_cleanup_queue;
 786
 787         error = ctrl->ctrl.ops->reg_read64(&ctrl->ctrl, NVME_REG_CAP,
 788                         &ctrl->ctrl.cap);
 789         if (error) {
 790                 dev_err(ctrl->ctrl.device,
 791                         "prop_get NVME_REG_CAP failed\n");
 792                 goto out_cleanup_queue;
 793         }
 794
 795         ctrl->ctrl.sqsize =
 796                 min_t(int, NVME_CAP_MQES(ctrl->ctrl.cap), ctrl->ctrl.sqsize);
 797
 798         error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
 799         if (error)
 800                 goto out_cleanup_queue;
 801
 802         ctrl->ctrl.max_hw_sectors =
 803                 (ctrl->max_fr_pages - 1) << (ilog2(SZ_4K) - 9);
 804
 805         error = nvme_init_identify(&ctrl->ctrl);
 806         if (error)
 807                 goto out_cleanup_queue;
 808
 809         error = nvme_rdma_alloc_qe(ctrl->queues[0].device->dev,
 810                         &ctrl->async_event_sqe, sizeof(struct nvme_command),
 811                         DMA_TO_DEVICE);
 812         if (error)
 813                 goto out_cleanup_queue;
 814
 815         return 0;
 816
 817 out_cleanup_queue:
 818         if (new)
 819                 blk_cleanup_queue(ctrl->ctrl.admin_q);
 820 out_free_tagset:
 821         if (new)
 822                 nvme_rdma_free_tagset(&ctrl->ctrl, true);
 823 out_free_queue:
 824         nvme_rdma_free_queue(&ctrl->queues[0]);
 825         return error;
 826 }
 827
 828 static void nvme_rdma_destroy_io_queues(struct nvme_rdma_ctrl *ctrl,
 829                 bool remove)
 830 {
 831         nvme_rdma_stop_io_queues(ctrl);
 832         if (remove) {
 833                 blk_cleanup_queue(ctrl->ctrl.connect_q);
 834                 nvme_rdma_free_tagset(&ctrl->ctrl, false);
 835         }
 836         nvme_rdma_free_io_queues(ctrl);
 837 }
 838
 839 static int nvme_rdma_configure_io_queues(struct nvme_rdma_ctrl *ctrl, bool new)
 840 {
 841         int ret;
 842
 843         ret = nvme_rdma_alloc_io_queues(ctrl);
 844         if (ret)
 845                 return ret;
 846
 847         if (new) {
 848                 ctrl->ctrl.tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, false);
 849                 if (IS_ERR(ctrl->ctrl.tagset))
 850                         goto out_free_io_queues;
 851
 852                 ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set);
 853                 if (IS_ERR(ctrl->ctrl.connect_q)) {
 854                         ret = PTR_ERR(ctrl->ctrl.connect_q);
 855                         goto out_free_tag_set;
 856                 }
 857         } else {
 858                 ret = blk_mq_reinit_tagset(&ctrl->tag_set,
 859                                            nvme_rdma_reinit_request);
 860                 if (ret)
 861                         goto out_free_io_queues;
 862
 863                 blk_mq_update_nr_hw_queues(&ctrl->tag_set,
 864                         ctrl->ctrl.queue_count - 1);
 865         }
 866
 867         ret = nvme_rdma_start_io_queues(ctrl);
 868         if (ret)
 869                 goto out_cleanup_connect_q;
 870
 871         return 0;
 872
 873 out_cleanup_connect_q:
 874         if (new)
 875                 blk_cleanup_queue(ctrl->ctrl.connect_q);
 876 out_free_tag_set:
 877         if (new)
 878                 nvme_rdma_free_tagset(&ctrl->ctrl, false);
 879 out_free_io_queues:
 880         nvme_rdma_free_io_queues(ctrl);
 881         return ret;
 882 }
 883
 884 static void nvme_rdma_free_ctrl(struct nvme_ctrl *nctrl)
 885 {
 886         struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
 887
 888         if (list_empty(&ctrl->list))
 889                 goto free_ctrl;
 890
 891         mutex_lock(&nvme_rdma_ctrl_mutex);
 892         list_del(&ctrl->list);
 893         mutex_unlock(&nvme_rdma_ctrl_mutex);
 894
 895         kfree(ctrl->queues);
 896         nvmf_free_options(nctrl->opts);
 897 free_ctrl:
 898         kfree(ctrl);
 899 }
 900
 901 static void nvme_rdma_reconnect_or_remove(struct nvme_rdma_ctrl *ctrl)
 902 {
 903         /* If we are resetting/deleting then do nothing */
 904         if (ctrl->ctrl.state != NVME_CTRL_RECONNECTING) {
 905                 WARN_ON_ONCE(ctrl->ctrl.state == NVME_CTRL_NEW ||
 906                         ctrl->ctrl.state == NVME_CTRL_LIVE);
 907                 return;
 908         }
 909
 910         if (nvmf_should_reconnect(&ctrl->ctrl)) {
 911                 dev_info(ctrl->ctrl.device, "Reconnecting in %d seconds...\n",
 912                         ctrl->ctrl.opts->reconnect_delay);
 913                 queue_delayed_work(nvme_wq, &ctrl->reconnect_work,
 914                                 ctrl->ctrl.opts->reconnect_delay * HZ);
 915         } else {
 916                 dev_info(ctrl->ctrl.device, "Removing controller...\n");
 917                 queue_work(nvme_wq, &ctrl->delete_work);
 918         }
 919 }
 920
 921 static void nvme_rdma_reconnect_ctrl_work(struct work_struct *work)
 922 {
 923         struct nvme_rdma_ctrl *ctrl = container_of(to_delayed_work(work),
 924                         struct nvme_rdma_ctrl, reconnect_work);
 925         bool changed;
 926         int ret;
 927
 928         ++ctrl->ctrl.nr_reconnects;
 929
 930         if (ctrl->ctrl.queue_count > 1)
 931                 nvme_rdma_destroy_io_queues(ctrl, false);
 932
 933         nvme_rdma_destroy_admin_queue(ctrl, false);
 934         ret = nvme_rdma_configure_admin_queue(ctrl, false);
 935         if (ret)
 936                 goto requeue;
 937
 938         if (ctrl->ctrl.queue_count > 1) {
 939                 ret = nvme_rdma_configure_io_queues(ctrl, false);
 940                 if (ret)
 941                         goto requeue;
 942         }
 943
 944         changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
 945         WARN_ON_ONCE(!changed);
 946         ctrl->ctrl.nr_reconnects = 0;
 947
 948         nvme_start_ctrl(&ctrl->ctrl);
 949
 950         dev_info(ctrl->ctrl.device, "Successfully reconnected\n");
 951
 952         return;
 953
 954 requeue:
 955         dev_info(ctrl->ctrl.device, "Failed reconnect attempt %d\n",
 956                         ctrl->ctrl.nr_reconnects);
 957         nvme_rdma_reconnect_or_remove(ctrl);
 958 }
 959
 960 static void nvme_rdma_error_recovery_work(struct work_struct *work)
 961 {
 962         struct nvme_rdma_ctrl *ctrl = container_of(work,
 963                         struct nvme_rdma_ctrl, err_work);
 964
 965         nvme_stop_ctrl(&ctrl->ctrl);
 966
 967         if (ctrl->ctrl.queue_count > 1) {
 968                 nvme_stop_queues(&ctrl->ctrl);
 969                 nvme_rdma_stop_io_queues(ctrl);
 970         }
 971         blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
 972         nvme_rdma_stop_queue(&ctrl->queues[0]);
 973
 974         /* We must take care of fastfail/requeue all our inflight requests */
 975         if (ctrl->ctrl.queue_count > 1)
 976                 blk_mq_tagset_busy_iter(&ctrl->tag_set,
 977                                         nvme_cancel_request, &ctrl->ctrl);
 978         blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
 979                                 nvme_cancel_request, &ctrl->ctrl);
 980
 981         /*
 982          * queues are not a live anymore, so restart the queues to fail fast
 983          * new IO
 984          */
 985         blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
 986         nvme_start_queues(&ctrl->ctrl);
 987
 988         nvme_rdma_reconnect_or_remove(ctrl);
 989 }
 990
 991 static void nvme_rdma_error_recovery(struct nvme_rdma_ctrl *ctrl)
 992 {
 993         if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RECONNECTING))
 994                 return;
 995
 996         queue_work(nvme_wq, &ctrl->err_work);
 997 }
 998
 999 static void nvme_rdma_wr_error(struct ib_cq *cq, struct ib_wc *wc,
1000                 const char *op)
1001 {
1002         struct nvme_rdma_queue *queue = cq->cq_context;
1003         struct nvme_rdma_ctrl *ctrl = queue->ctrl;
1004
1005         if (ctrl->ctrl.state == NVME_CTRL_LIVE)
1006                 dev_info(ctrl->ctrl.device,
1007                              "%s for CQE 0x%p failed with status %s (%d)\n",
1008                              op, wc->wr_cqe,
1009                              ib_wc_status_msg(wc->status), wc->status);
1010         nvme_rdma_error_recovery(ctrl);
1011 }
1012
1013 static void nvme_rdma_memreg_done(struct ib_cq *cq, struct ib_wc *wc)
1014 {
1015         if (unlikely(wc->status != IB_WC_SUCCESS))
1016                 nvme_rdma_wr_error(cq, wc, "MEMREG");
1017 }
1018
1019 static void nvme_rdma_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc)
1020 {
1021         if (unlikely(wc->status != IB_WC_SUCCESS))
1022                 nvme_rdma_wr_error(cq, wc, "LOCAL_INV");
1023 }
1024
1025 static int nvme_rdma_inv_rkey(struct nvme_rdma_queue *queue,
1026                 struct nvme_rdma_request *req)
1027 {
1028         struct ib_send_wr *bad_wr;
1029         struct ib_send_wr wr = {
1030                 .opcode             = IB_WR_LOCAL_INV,
1031                 .next               = NULL,
1032                 .num_sge            = 0,
1033                 .send_flags         = 0,
1034                 .ex.invalidate_rkey = req->mr->rkey,
1035         };
1036
1037         req->reg_cqe.done = nvme_rdma_inv_rkey_done;
1038         wr.wr_cqe = &req->reg_cqe;
1039
1040         return ib_post_send(queue->qp, &wr, &bad_wr);
1041 }
1042
1043 static void nvme_rdma_unmap_data(struct nvme_rdma_queue *queue,
1044                 struct request *rq)
1045 {
1046         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1047         struct nvme_rdma_ctrl *ctrl = queue->ctrl;
1048         struct nvme_rdma_device *dev = queue->device;
1049         struct ib_device *ibdev = dev->dev;
1050         int res;
1051
1052         if (!blk_rq_bytes(rq))
1053                 return;
1054
1055         if (req->mr->need_inval) {
1056                 res = nvme_rdma_inv_rkey(queue, req);
1057                 if (unlikely(res < 0)) {
1058                         dev_err(ctrl->ctrl.device,
1059                                 "Queueing INV WR for rkey %#x failed (%d)\n",
1060                                 req->mr->rkey, res);
1061                         nvme_rdma_error_recovery(queue->ctrl);
1062                 }
1063         }
1064
1065         ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
1066                         req->nents, rq_data_dir(rq) ==
1067                                     WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1068
1069         nvme_cleanup_cmd(rq);
1070         sg_free_table_chained(&req->sg_table, true);
1071 }
1072
1073 static int nvme_rdma_set_sg_null(struct nvme_command *c)
1074 {
1075         struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
1076
1077         sg->addr = 0;
1078         put_unaligned_le24(0, sg->length);
1079         put_unaligned_le32(0, sg->key);
1080         sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
1081         return 0;
1082 }
1083
1084 static int nvme_rdma_map_sg_inline(struct nvme_rdma_queue *queue,
1085                 struct nvme_rdma_request *req, struct nvme_command *c)
1086 {
1087         struct nvme_sgl_desc *sg = &c->common.dptr.sgl;
1088
1089         req->sge[1].addr = sg_dma_address(req->sg_table.sgl);
1090         req->sge[1].length = sg_dma_len(req->sg_table.sgl);
1091         req->sge[1].lkey = queue->device->pd->local_dma_lkey;
1092
1093         sg->addr = cpu_to_le64(queue->ctrl->ctrl.icdoff);
1094         sg->length = cpu_to_le32(sg_dma_len(req->sg_table.sgl));
1095         sg->type = (NVME_SGL_FMT_DATA_DESC << 4) | NVME_SGL_FMT_OFFSET;
1096
1097         req->inline_data = true;
1098         req->num_sge++;
1099         return 0;
1100 }
1101
1102 static int nvme_rdma_map_sg_single(struct nvme_rdma_queue *queue,
1103                 struct nvme_rdma_request *req, struct nvme_command *c)
1104 {
1105         struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
1106
1107         sg->addr = cpu_to_le64(sg_dma_address(req->sg_table.sgl));
1108         put_unaligned_le24(sg_dma_len(req->sg_table.sgl), sg->length);
1109         put_unaligned_le32(queue->device->pd->unsafe_global_rkey, sg->key);
1110         sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
1111         return 0;
1112 }
1113
1114 static int nvme_rdma_map_sg_fr(struct nvme_rdma_queue *queue,
1115                 struct nvme_rdma_request *req, struct nvme_command *c,
1116                 int count)
1117 {
1118         struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
1119         int nr;
1120
1121         /*
1122          * Align the MR to a 4K page size to match the ctrl page size and
1123          * the block virtual boundary.
1124          */
1125         nr = ib_map_mr_sg(req->mr, req->sg_table.sgl, count, NULL, SZ_4K);
1126         if (unlikely(nr < count)) {
1127                 if (nr < 0)
1128                         return nr;
1129                 return -EINVAL;
1130         }
1131
1132         ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey));
1133
1134         req->reg_cqe.done = nvme_rdma_memreg_done;
1135         memset(&req->reg_wr, 0, sizeof(req->reg_wr));
1136         req->reg_wr.wr.opcode = IB_WR_REG_MR;
1137         req->reg_wr.wr.wr_cqe = &req->reg_cqe;
1138         req->reg_wr.wr.num_sge = 0;
1139         req->reg_wr.mr = req->mr;
1140         req->reg_wr.key = req->mr->rkey;
1141         req->reg_wr.access = IB_ACCESS_LOCAL_WRITE |
1142                              IB_ACCESS_REMOTE_READ |
1143                              IB_ACCESS_REMOTE_WRITE;
1144
1145         req->mr->need_inval = true;
1146
1147         sg->addr = cpu_to_le64(req->mr->iova);
1148         put_unaligned_le24(req->mr->length, sg->length);
1149         put_unaligned_le32(req->mr->rkey, sg->key);
1150         sg->type = (NVME_KEY_SGL_FMT_DATA_DESC << 4) |
1151                         NVME_SGL_FMT_INVALIDATE;
1152
1153         return 0;
1154 }
1155
1156 static int nvme_rdma_map_data(struct nvme_rdma_queue *queue,
1157                 struct request *rq, struct nvme_command *c)
1158 {
1159         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1160         struct nvme_rdma_device *dev = queue->device;
1161         struct ib_device *ibdev = dev->dev;
1162         int count, ret;
1163
1164         req->num_sge = 1;
1165         req->inline_data = false;
1166         req->mr->need_inval = false;
1167
1168         c->common.flags |= NVME_CMD_SGL_METABUF;
1169
1170         if (!blk_rq_bytes(rq))
1171                 return nvme_rdma_set_sg_null(c);
1172
1173         req->sg_table.sgl = req->first_sgl;
1174         ret = sg_alloc_table_chained(&req->sg_table,
1175                         blk_rq_nr_phys_segments(rq), req->sg_table.sgl);
1176         if (ret)
1177                 return -ENOMEM;
1178
1179         req->nents = blk_rq_map_sg(rq->q, rq, req->sg_table.sgl);
1180
1181         count = ib_dma_map_sg(ibdev, req->sg_table.sgl, req->nents,
1182                     rq_data_dir(rq) == WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1183         if (unlikely(count <= 0)) {
1184                 sg_free_table_chained(&req->sg_table, true);
1185                 return -EIO;
1186         }
1187
1188         if (count == 1) {
1189                 if (rq_data_dir(rq) == WRITE && nvme_rdma_queue_idx(queue) &&
1190                     blk_rq_payload_bytes(rq) <=
1191                                 nvme_rdma_inline_data_size(queue))
1192                         return nvme_rdma_map_sg_inline(queue, req, c);
1193
1194                 if (dev->pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)
1195                         return nvme_rdma_map_sg_single(queue, req, c);
1196         }
1197
1198         return nvme_rdma_map_sg_fr(queue, req, c, count);
1199 }
1200
1201 static void nvme_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
1202 {
1203         if (unlikely(wc->status != IB_WC_SUCCESS))
1204                 nvme_rdma_wr_error(cq, wc, "SEND");
1205 }
1206
1207 /*
1208  * We want to signal completion at least every queue depth/2.  This returns the
1209  * largest power of two that is not above half of (queue size + 1) to optimize
1210  * (avoid divisions).
1211  */
1212 static inline bool nvme_rdma_queue_sig_limit(struct nvme_rdma_queue *queue)
1213 {
1214         int limit = 1 << ilog2((queue->queue_size + 1) / 2);
1215
1216         return (atomic_inc_return(&queue->sig_count) & (limit - 1)) == 0;
1217 }
1218
1219 static int nvme_rdma_post_send(struct nvme_rdma_queue *queue,
1220                 struct nvme_rdma_qe *qe, struct ib_sge *sge, u32 num_sge,
1221                 struct ib_send_wr *first, bool flush)
1222 {
1223         struct ib_send_wr wr, *bad_wr;
1224         int ret;
1225
1226         sge->addr   = qe->dma;
1227         sge->length = sizeof(struct nvme_command),
1228         sge->lkey   = queue->device->pd->local_dma_lkey;
1229
1230         qe->cqe.done = nvme_rdma_send_done;
1231
1232         wr.next       = NULL;
1233         wr.wr_cqe     = &qe->cqe;
1234         wr.sg_list    = sge;
1235         wr.num_sge    = num_sge;
1236         wr.opcode     = IB_WR_SEND;
1237         wr.send_flags = 0;
1238
1239         /*
1240          * Unsignalled send completions are another giant desaster in the
1241          * IB Verbs spec:  If we don't regularly post signalled sends
1242          * the send queue will fill up and only a QP reset will rescue us.
1243          * Would have been way to obvious to handle this in hardware or
1244          * at least the RDMA stack..
1245          *
1246          * Always signal the flushes. The magic request used for the flush
1247          * sequencer is not allocated in our driver's tagset and it's
1248          * triggered to be freed by blk_cleanup_queue(). So we need to
1249          * always mark it as signaled to ensure that the "wr_cqe", which is
1250          * embedded in request's payload, is not freed when __ib_process_cq()
1251          * calls wr_cqe->done().
1252          */
1253         if (nvme_rdma_queue_sig_limit(queue) || flush)
1254                 wr.send_flags |= IB_SEND_SIGNALED;
1255
1256         if (first)
1257                 first->next = &wr;
1258         else
1259                 first = &wr;
1260
1261         ret = ib_post_send(queue->qp, first, &bad_wr);
1262         if (unlikely(ret)) {
1263                 dev_err(queue->ctrl->ctrl.device,
1264                              "%s failed with error code %d\n", __func__, ret);
1265         }
1266         return ret;
1267 }
1268
1269 static int nvme_rdma_post_recv(struct nvme_rdma_queue *queue,
1270                 struct nvme_rdma_qe *qe)
1271 {
1272         struct ib_recv_wr wr, *bad_wr;
1273         struct ib_sge list;
1274         int ret;
1275
1276         list.addr   = qe->dma;
1277         list.length = sizeof(struct nvme_completion);
1278         list.lkey   = queue->device->pd->local_dma_lkey;
1279
1280         qe->cqe.done = nvme_rdma_recv_done;
1281
1282         wr.next     = NULL;
1283         wr.wr_cqe   = &qe->cqe;
1284         wr.sg_list  = &list;
1285         wr.num_sge  = 1;
1286
1287         ret = ib_post_recv(queue->qp, &wr, &bad_wr);
1288         if (unlikely(ret)) {
1289                 dev_err(queue->ctrl->ctrl.device,
1290                         "%s failed with error code %d\n", __func__, ret);
1291         }
1292         return ret;
1293 }
1294
1295 static struct blk_mq_tags *nvme_rdma_tagset(struct nvme_rdma_queue *queue)
1296 {
1297         u32 queue_idx = nvme_rdma_queue_idx(queue);
1298
1299         if (queue_idx == 0)
1300                 return queue->ctrl->admin_tag_set.tags[queue_idx];
1301         return queue->ctrl->tag_set.tags[queue_idx - 1];
1302 }
1303
1304 static void nvme_rdma_submit_async_event(struct nvme_ctrl *arg, int aer_idx)
1305 {
1306         struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(arg);
1307         struct nvme_rdma_queue *queue = &ctrl->queues[0];
1308         struct ib_device *dev = queue->device->dev;
1309         struct nvme_rdma_qe *sqe = &ctrl->async_event_sqe;
1310         struct nvme_command *cmd = sqe->data;
1311         struct ib_sge sge;
1312         int ret;
1313
1314         if (WARN_ON_ONCE(aer_idx != 0))
1315                 return;
1316
1317         ib_dma_sync_single_for_cpu(dev, sqe->dma, sizeof(*cmd), DMA_TO_DEVICE);
1318
1319         memset(cmd, 0, sizeof(*cmd));
1320         cmd->common.opcode = nvme_admin_async_event;
1321         cmd->common.command_id = NVME_RDMA_AQ_BLKMQ_DEPTH;
1322         cmd->common.flags |= NVME_CMD_SGL_METABUF;
1323         nvme_rdma_set_sg_null(cmd);
1324
1325         ib_dma_sync_single_for_device(dev, sqe->dma, sizeof(*cmd),
1326                         DMA_TO_DEVICE);
1327
1328         ret = nvme_rdma_post_send(queue, sqe, &sge, 1, NULL, false);
1329         WARN_ON_ONCE(ret);
1330 }
1331
1332 static int nvme_rdma_process_nvme_rsp(struct nvme_rdma_queue *queue,
1333                 struct nvme_completion *cqe, struct ib_wc *wc, int tag)
1334 {
1335         struct request *rq;
1336         struct nvme_rdma_request *req;
1337         int ret = 0;
1338
1339         rq = blk_mq_tag_to_rq(nvme_rdma_tagset(queue), cqe->command_id);
1340         if (!rq) {
1341                 dev_err(queue->ctrl->ctrl.device,
1342                         "tag 0x%x on QP %#x not found\n",
1343                         cqe->command_id, queue->qp->qp_num);
1344                 nvme_rdma_error_recovery(queue->ctrl);
1345                 return ret;
1346         }
1347         req = blk_mq_rq_to_pdu(rq);
1348
1349         if (rq->tag == tag)
1350                 ret = 1;
1351
1352         if ((wc->wc_flags & IB_WC_WITH_INVALIDATE) &&
1353             wc->ex.invalidate_rkey == req->mr->rkey)
1354                 req->mr->need_inval = false;
1355
1356         nvme_end_request(rq, cqe->status, cqe->result);
1357         return ret;
1358 }
1359
1360 static int __nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc, int tag)
1361 {
1362         struct nvme_rdma_qe *qe =
1363                 container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
1364         struct nvme_rdma_queue *queue = cq->cq_context;
1365         struct ib_device *ibdev = queue->device->dev;
1366         struct nvme_completion *cqe = qe->data;
1367         const size_t len = sizeof(struct nvme_completion);
1368         int ret = 0;
1369
1370         if (unlikely(wc->status != IB_WC_SUCCESS)) {
1371                 nvme_rdma_wr_error(cq, wc, "RECV");
1372                 return 0;
1373         }
1374
1375         ib_dma_sync_single_for_cpu(ibdev, qe->dma, len, DMA_FROM_DEVICE);
1376         /*
1377          * AEN requests are special as they don't time out and can
1378          * survive any kind of queue freeze and often don't respond to
1379          * aborts.  We don't even bother to allocate a struct request
1380          * for them but rather special case them here.
1381          */
1382         if (unlikely(nvme_rdma_queue_idx(queue) == 0 &&
1383                         cqe->command_id >= NVME_RDMA_AQ_BLKMQ_DEPTH))
1384                 nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status,
1385                                 &cqe->result);
1386         else
1387                 ret = nvme_rdma_process_nvme_rsp(queue, cqe, wc, tag);
1388         ib_dma_sync_single_for_device(ibdev, qe->dma, len, DMA_FROM_DEVICE);
1389
1390         nvme_rdma_post_recv(queue, qe);
1391         return ret;
1392 }
1393
1394 static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1395 {
1396         __nvme_rdma_recv_done(cq, wc, -1);
1397 }
1398
1399 static int nvme_rdma_conn_established(struct nvme_rdma_queue *queue)
1400 {
1401         int ret, i;
1402
1403         for (i = 0; i < queue->queue_size; i++) {
1404                 ret = nvme_rdma_post_recv(queue, &queue->rsp_ring[i]);
1405                 if (ret)
1406                         goto out_destroy_queue_ib;
1407         }
1408
1409         return 0;
1410
1411 out_destroy_queue_ib:
1412         nvme_rdma_destroy_queue_ib(queue);
1413         return ret;
1414 }
1415
1416 static int nvme_rdma_conn_rejected(struct nvme_rdma_queue *queue,
1417                 struct rdma_cm_event *ev)
1418 {
1419         struct rdma_cm_id *cm_id = queue->cm_id;
1420         int status = ev->status;
1421         const char *rej_msg;
1422         const struct nvme_rdma_cm_rej *rej_data;
1423         u8 rej_data_len;
1424
1425         rej_msg = rdma_reject_msg(cm_id, status);
1426         rej_data = rdma_consumer_reject_data(cm_id, ev, &rej_data_len);
1427
1428         if (rej_data && rej_data_len >= sizeof(u16)) {
1429                 u16 sts = le16_to_cpu(rej_data->sts);
1430
1431                 dev_err(queue->ctrl->ctrl.device,
1432                       "Connect rejected: status %d (%s) nvme status %d (%s).\n",
1433                       status, rej_msg, sts, nvme_rdma_cm_msg(sts));
1434         } else {
1435                 dev_err(queue->ctrl->ctrl.device,
1436                         "Connect rejected: status %d (%s).\n", status, rej_msg);
1437         }
1438
1439         return -ECONNRESET;
1440 }
1441
1442 static int nvme_rdma_addr_resolved(struct nvme_rdma_queue *queue)
1443 {
1444         int ret;
1445
1446         ret = nvme_rdma_create_queue_ib(queue);
1447         if (ret)
1448                 return ret;
1449
1450         ret = rdma_resolve_route(queue->cm_id, NVME_RDMA_CONNECT_TIMEOUT_MS);
1451         if (ret) {
1452                 dev_err(queue->ctrl->ctrl.device,
1453                         "rdma_resolve_route failed (%d).\n",
1454                         queue->cm_error);
1455                 goto out_destroy_queue;
1456         }
1457
1458         return 0;
1459
1460 out_destroy_queue:
1461         nvme_rdma_destroy_queue_ib(queue);
1462         return ret;
1463 }
1464
1465 static int nvme_rdma_route_resolved(struct nvme_rdma_queue *queue)
1466 {
1467         struct nvme_rdma_ctrl *ctrl = queue->ctrl;
1468         struct rdma_conn_param param = { };
1469         struct nvme_rdma_cm_req priv = { };
1470         int ret;
1471
1472         param.qp_num = queue->qp->qp_num;
1473         param.flow_control = 1;
1474
1475         param.responder_resources = queue->device->dev->attrs.max_qp_rd_atom;
1476         /* maximum retry count */
1477         param.retry_count = 7;
1478         param.rnr_retry_count = 7;
1479         param.private_data = &priv;
1480         param.private_data_len = sizeof(priv);
1481
1482         priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
1483         priv.qid = cpu_to_le16(nvme_rdma_queue_idx(queue));
1484         /*
1485          * set the admin queue depth to the minimum size
1486          * specified by the Fabrics standard.
1487          */
1488         if (priv.qid == 0) {
1489                 priv.hrqsize = cpu_to_le16(NVME_AQ_DEPTH);
1490                 priv.hsqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
1491         } else {
1492                 /*
1493                  * current interpretation of the fabrics spec
1494                  * is at minimum you make hrqsize sqsize+1, or a
1495                  * 1's based representation of sqsize.
1496                  */
1497                 priv.hrqsize = cpu_to_le16(queue->queue_size);
1498                 priv.hsqsize = cpu_to_le16(queue->ctrl->ctrl.sqsize);
1499         }
1500
1501         ret = rdma_connect(queue->cm_id, &param);
1502         if (ret) {
1503                 dev_err(ctrl->ctrl.device,
1504                         "rdma_connect failed (%d).\n", ret);
1505                 goto out_destroy_queue_ib;
1506         }
1507
1508         return 0;
1509
1510 out_destroy_queue_ib:
1511         nvme_rdma_destroy_queue_ib(queue);
1512         return ret;
1513 }
1514
1515 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
1516                 struct rdma_cm_event *ev)
1517 {
1518         struct nvme_rdma_queue *queue = cm_id->context;
1519         int cm_error = 0;
1520
1521         dev_dbg(queue->ctrl->ctrl.device, "%s (%d): status %d id %p\n",
1522                 rdma_event_msg(ev->event), ev->event,
1523                 ev->status, cm_id);
1524
1525         switch (ev->event) {
1526         case RDMA_CM_EVENT_ADDR_RESOLVED:
1527                 cm_error = nvme_rdma_addr_resolved(queue);
1528                 break;
1529         case RDMA_CM_EVENT_ROUTE_RESOLVED:
1530                 cm_error = nvme_rdma_route_resolved(queue);
1531                 break;
1532         case RDMA_CM_EVENT_ESTABLISHED:
1533                 queue->cm_error = nvme_rdma_conn_established(queue);
1534                 /* complete cm_done regardless of success/failure */
1535                 complete(&queue->cm_done);
1536                 return 0;
1537         case RDMA_CM_EVENT_REJECTED:
1538                 nvme_rdma_destroy_queue_ib(queue);
1539                 cm_error = nvme_rdma_conn_rejected(queue, ev);
1540                 break;
1541         case RDMA_CM_EVENT_ROUTE_ERROR:
1542         case RDMA_CM_EVENT_CONNECT_ERROR:
1543         case RDMA_CM_EVENT_UNREACHABLE:
1544                 nvme_rdma_destroy_queue_ib(queue);
1545         case RDMA_CM_EVENT_ADDR_ERROR:
1546                 dev_dbg(queue->ctrl->ctrl.device,
1547                         "CM error event %d\n", ev->event);
1548                 cm_error = -ECONNRESET;
1549                 break;
1550         case RDMA_CM_EVENT_DISCONNECTED:
1551         case RDMA_CM_EVENT_ADDR_CHANGE:
1552         case RDMA_CM_EVENT_TIMEWAIT_EXIT:
1553                 dev_dbg(queue->ctrl->ctrl.device,
1554                         "disconnect received - connection closed\n");
1555                 nvme_rdma_error_recovery(queue->ctrl);
1556                 break;
1557         case RDMA_CM_EVENT_DEVICE_REMOVAL:
1558                 /* device removal is handled via the ib_client API */
1559                 break;
1560         default:
1561                 dev_err(queue->ctrl->ctrl.device,
1562                         "Unexpected RDMA CM event (%d)\n", ev->event);
1563                 nvme_rdma_error_recovery(queue->ctrl);
1564                 break;
1565         }
1566
1567         if (cm_error) {
1568                 queue->cm_error = cm_error;
1569                 complete(&queue->cm_done);
1570         }
1571
1572         return 0;
1573 }
1574
1575 static enum blk_eh_timer_return
1576 nvme_rdma_timeout(struct request *rq, bool reserved)
1577 {
1578         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1579
1580         /* queue error recovery */
1581         nvme_rdma_error_recovery(req->queue->ctrl);
1582
1583         /* fail with DNR on cmd timeout */
1584         nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR;
1585
1586         return BLK_EH_HANDLED;
1587 }
1588
1589 /*
1590  * We cannot accept any other command until the Connect command has completed.
1591  */
1592 static inline blk_status_t
1593 nvme_rdma_queue_is_ready(struct nvme_rdma_queue *queue, struct request *rq)
1594 {
1595         if (unlikely(!test_bit(NVME_RDMA_Q_LIVE, &queue->flags))) {
1596                 struct nvme_command *cmd = nvme_req(rq)->cmd;
1597
1598                 if (!blk_rq_is_passthrough(rq) ||
1599                     cmd->common.opcode != nvme_fabrics_command ||
1600                     cmd->fabrics.fctype != nvme_fabrics_type_connect) {
1601                         /*
1602                          * reconnecting state means transport disruption, which
1603                          * can take a long time and even might fail permanently,
1604                          * so we can't let incoming I/O be requeued forever.
1605                          * fail it fast to allow upper layers a chance to
1606                          * failover.
1607                          */
1608                         if (queue->ctrl->ctrl.state == NVME_CTRL_RECONNECTING)
1609                                 return BLK_STS_IOERR;
1610                         return BLK_STS_RESOURCE; /* try again later */
1611                 }
1612         }
1613
1614         return 0;
1615 }
1616
1617 static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
1618                 const struct blk_mq_queue_data *bd)
1619 {
1620         struct nvme_ns *ns = hctx->queue->queuedata;
1621         struct nvme_rdma_queue *queue = hctx->driver_data;
1622         struct request *rq = bd->rq;
1623         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1624         struct nvme_rdma_qe *sqe = &req->sqe;
1625         struct nvme_command *c = sqe->data;
1626         bool flush = false;
1627         struct ib_device *dev;
1628         blk_status_t ret;
1629         int err;
1630
1631         WARN_ON_ONCE(rq->tag < 0);
1632
1633         ret = nvme_rdma_queue_is_ready(queue, rq);
1634         if (unlikely(ret))
1635                 return ret;
1636
1637         dev = queue->device->dev;
1638         ib_dma_sync_single_for_cpu(dev, sqe->dma,
1639                         sizeof(struct nvme_command), DMA_TO_DEVICE);
1640
1641         ret = nvme_setup_cmd(ns, rq, c);
1642         if (ret)
1643                 return ret;
1644
1645         blk_mq_start_request(rq);
1646
1647         err = nvme_rdma_map_data(queue, rq, c);
1648         if (unlikely(err < 0)) {
1649                 dev_err(queue->ctrl->ctrl.device,
1650                              "Failed to map data (%d)\n", err);
1651                 nvme_cleanup_cmd(rq);
1652                 goto err;
1653         }
1654
1655         ib_dma_sync_single_for_device(dev, sqe->dma,
1656                         sizeof(struct nvme_command), DMA_TO_DEVICE);
1657
1658         if (req_op(rq) == REQ_OP_FLUSH)
1659                 flush = true;
1660         err = nvme_rdma_post_send(queue, sqe, req->sge, req->num_sge,
1661                         req->mr->need_inval ? &req->reg_wr.wr : NULL, flush);
1662         if (unlikely(err)) {
1663                 nvme_rdma_unmap_data(queue, rq);
1664                 goto err;
1665         }
1666
1667         return BLK_STS_OK;
1668 err:
1669         if (err == -ENOMEM || err == -EAGAIN)
1670                 return BLK_STS_RESOURCE;
1671         return BLK_STS_IOERR;
1672 }
1673
1674 static int nvme_rdma_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
1675 {
1676         struct nvme_rdma_queue *queue = hctx->driver_data;
1677         struct ib_cq *cq = queue->ib_cq;
1678         struct ib_wc wc;
1679         int found = 0;
1680
1681         while (ib_poll_cq(cq, 1, &wc) > 0) {
1682                 struct ib_cqe *cqe = wc.wr_cqe;
1683
1684                 if (cqe) {
1685                         if (cqe->done == nvme_rdma_recv_done)
1686                                 found |= __nvme_rdma_recv_done(cq, &wc, tag);
1687                         else
1688                                 cqe->done(cq, &wc);
1689                 }
1690         }
1691
1692         return found;
1693 }
1694
1695 static void nvme_rdma_complete_rq(struct request *rq)
1696 {
1697         struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1698
1699         nvme_rdma_unmap_data(req->queue, rq);
1700         nvme_complete_rq(rq);
1701 }
1702
1703 static int nvme_rdma_map_queues(struct blk_mq_tag_set *set)
1704 {
1705         struct nvme_rdma_ctrl *ctrl = set->driver_data;
1706
1707         return blk_mq_rdma_map_queues(set, ctrl->device->dev, 0);
1708 }
1709
1710 static const struct blk_mq_ops nvme_rdma_mq_ops = {
1711         .queue_rq       = nvme_rdma_queue_rq,
1712         .complete       = nvme_rdma_complete_rq,
1713         .init_request   = nvme_rdma_init_request,
1714         .exit_request   = nvme_rdma_exit_request,
1715         .init_hctx      = nvme_rdma_init_hctx,
1716         .poll           = nvme_rdma_poll,
1717         .timeout        = nvme_rdma_timeout,
1718         .map_queues     = nvme_rdma_map_queues,
1719 };
1720
1721 static const struct blk_mq_ops nvme_rdma_admin_mq_ops = {
1722         .queue_rq       = nvme_rdma_queue_rq,
1723         .complete       = nvme_rdma_complete_rq,
1724         .init_request   = nvme_rdma_init_request,
1725         .exit_request   = nvme_rdma_exit_request,
1726         .init_hctx      = nvme_rdma_init_admin_hctx,
1727         .timeout        = nvme_rdma_timeout,
1728 };
1729
1730 static void nvme_rdma_shutdown_ctrl(struct nvme_rdma_ctrl *ctrl, bool shutdown)
1731 {
1732         cancel_work_sync(&ctrl->err_work);
1733         cancel_delayed_work_sync(&ctrl->reconnect_work);
1734
1735         if (ctrl->ctrl.queue_count > 1) {
1736                 nvme_stop_queues(&ctrl->ctrl);
1737                 blk_mq_tagset_busy_iter(&ctrl->tag_set,
1738                                         nvme_cancel_request, &ctrl->ctrl);
1739                 nvme_rdma_destroy_io_queues(ctrl, shutdown);
1740         }
1741
1742         if (shutdown)
1743                 nvme_shutdown_ctrl(&ctrl->ctrl);
1744         else
1745                 nvme_disable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
1746
1747         blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
1748         blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
1749                                 nvme_cancel_request, &ctrl->ctrl);
1750         blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
1751         nvme_rdma_destroy_admin_queue(ctrl, shutdown);
1752 }
1753
1754 static void nvme_rdma_remove_ctrl(struct nvme_rdma_ctrl *ctrl)
1755 {
1756         nvme_remove_namespaces(&ctrl->ctrl);
1757         nvme_rdma_shutdown_ctrl(ctrl, true);
1758         nvme_uninit_ctrl(&ctrl->ctrl);
1759         nvme_put_ctrl(&ctrl->ctrl);
1760 }
1761
1762 static void nvme_rdma_del_ctrl_work(struct work_struct *work)
1763 {
1764         struct nvme_rdma_ctrl *ctrl = container_of(work,
1765                                 struct nvme_rdma_ctrl, delete_work);
1766
1767         nvme_stop_ctrl(&ctrl->ctrl);
1768         nvme_rdma_remove_ctrl(ctrl);
1769 }
1770
1771 static int __nvme_rdma_del_ctrl(struct nvme_rdma_ctrl *ctrl)
1772 {
1773         if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING))
1774                 return -EBUSY;
1775
1776         if (!queue_work(nvme_wq, &ctrl->delete_work))
1777                 return -EBUSY;
1778
1779         return 0;
1780 }
1781
1782 static int nvme_rdma_del_ctrl(struct nvme_ctrl *nctrl)
1783 {
1784         struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
1785         int ret = 0;
1786
1787         /*
1788          * Keep a reference until all work is flushed since
1789          * __nvme_rdma_del_ctrl can free the ctrl mem
1790          */
1791         if (!kref_get_unless_zero(&ctrl->ctrl.kref))
1792                 return -EBUSY;
1793         ret = __nvme_rdma_del_ctrl(ctrl);
1794         if (!ret)
1795                 flush_work(&ctrl->delete_work);
1796         nvme_put_ctrl(&ctrl->ctrl);
1797         return ret;
1798 }
1799
1800 static void nvme_rdma_reset_ctrl_work(struct work_struct *work)
1801 {
1802         struct nvme_rdma_ctrl *ctrl =
1803                 container_of(work, struct nvme_rdma_ctrl, ctrl.reset_work);
1804         int ret;
1805         bool changed;
1806
1807         nvme_stop_ctrl(&ctrl->ctrl);
1808         nvme_rdma_shutdown_ctrl(ctrl, false);
1809
1810         ret = nvme_rdma_configure_admin_queue(ctrl, false);
1811         if (ret)
1812                 goto out_fail;
1813
1814         if (ctrl->ctrl.queue_count > 1) {
1815                 ret = nvme_rdma_configure_io_queues(ctrl, false);
1816                 if (ret)
1817                         goto out_fail;
1818         }
1819
1820         changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
1821         WARN_ON_ONCE(!changed);
1822
1823         nvme_start_ctrl(&ctrl->ctrl);
1824
1825         return;
1826
1827 out_fail:
1828         dev_warn(ctrl->ctrl.device, "Removing after reset failure\n");
1829         nvme_rdma_remove_ctrl(ctrl);
1830 }
1831
1832 static const struct nvme_ctrl_ops nvme_rdma_ctrl_ops = {
1833         .name                   = "rdma",
1834         .module                 = THIS_MODULE,
1835         .flags                  = NVME_F_FABRICS,
1836         .reg_read32             = nvmf_reg_read32,
1837         .reg_read64             = nvmf_reg_read64,
1838         .reg_write32            = nvmf_reg_write32,
1839         .free_ctrl              = nvme_rdma_free_ctrl,
1840         .submit_async_event     = nvme_rdma_submit_async_event,
1841         .delete_ctrl            = nvme_rdma_del_ctrl,
1842         .get_address            = nvmf_get_address,
1843 };
1844
1845 static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
1846                 struct nvmf_ctrl_options *opts)
1847 {
1848         struct nvme_rdma_ctrl *ctrl;
1849         int ret;
1850         bool changed;
1851         char *port;
1852
1853         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1854         if (!ctrl)
1855                 return ERR_PTR(-ENOMEM);
1856         ctrl->ctrl.opts = opts;
1857         INIT_LIST_HEAD(&ctrl->list);
1858
1859         if (opts->mask & NVMF_OPT_TRSVCID)
1860                 port = opts->trsvcid;
1861         else
1862                 port = __stringify(NVME_RDMA_IP_PORT);
1863
1864         ret = inet_pton_with_scope(&init_net, AF_UNSPEC,
1865                         opts->traddr, port, &ctrl->addr);
1866         if (ret) {
1867                 pr_err("malformed address passed: %s:%s\n", opts->traddr, port);
1868                 goto out_free_ctrl;
1869         }
1870
1871         if (opts->mask & NVMF_OPT_HOST_TRADDR) {
1872                 ret = inet_pton_with_scope(&init_net, AF_UNSPEC,
1873                         opts->host_traddr, NULL, &ctrl->src_addr);
1874                 if (ret) {
1875                         pr_err("malformed src address passed: %s\n",
1876                                opts->host_traddr);
1877                         goto out_free_ctrl;
1878                 }
1879         }
1880
1881         ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_rdma_ctrl_ops,
1882                                 0 /* no quirks, we're perfect! */);
1883         if (ret)
1884                 goto out_free_ctrl;
1885
1886         INIT_DELAYED_WORK(&ctrl->reconnect_work,
1887                         nvme_rdma_reconnect_ctrl_work);
1888         INIT_WORK(&ctrl->err_work, nvme_rdma_error_recovery_work);
1889         INIT_WORK(&ctrl->delete_work, nvme_rdma_del_ctrl_work);
1890         INIT_WORK(&ctrl->ctrl.reset_work, nvme_rdma_reset_ctrl_work);
1891
1892         ctrl->ctrl.queue_count = opts->nr_io_queues + 1; /* +1 for admin queue */
1893         ctrl->ctrl.sqsize = opts->queue_size - 1;
1894         ctrl->ctrl.kato = opts->kato;
1895
1896         ret = -ENOMEM;
1897         ctrl->queues = kcalloc(ctrl->ctrl.queue_count, sizeof(*ctrl->queues),
1898                                 GFP_KERNEL);
1899         if (!ctrl->queues)
1900                 goto out_uninit_ctrl;
1901
1902         ret = nvme_rdma_configure_admin_queue(ctrl, true);
1903         if (ret)
1904                 goto out_kfree_queues;
1905
1906         /* sanity check icdoff */
1907         if (ctrl->ctrl.icdoff) {
1908                 dev_err(ctrl->ctrl.device, "icdoff is not supported!\n");
1909                 ret = -EINVAL;
1910                 goto out_remove_admin_queue;
1911         }
1912
1913         /* sanity check keyed sgls */
1914         if (!(ctrl->ctrl.sgls & (1 << 20))) {
1915                 dev_err(ctrl->ctrl.device, "Mandatory keyed sgls are not support\n");
1916                 ret = -EINVAL;
1917                 goto out_remove_admin_queue;
1918         }
1919
1920         if (opts->queue_size > ctrl->ctrl.maxcmd) {
1921                 /* warn if maxcmd is lower than queue_size */
1922                 dev_warn(ctrl->ctrl.device,
1923                         "queue_size %zu > ctrl maxcmd %u, clamping down\n",
1924                         opts->queue_size, ctrl->ctrl.maxcmd);
1925                 opts->queue_size = ctrl->ctrl.maxcmd;
1926         }
1927
1928         if (opts->queue_size > ctrl->ctrl.sqsize + 1) {
1929                 /* warn if sqsize is lower than queue_size */
1930                 dev_warn(ctrl->ctrl.device,
1931                         "queue_size %zu > ctrl sqsize %u, clamping down\n",
1932                         opts->queue_size, ctrl->ctrl.sqsize + 1);
1933                 opts->queue_size = ctrl->ctrl.sqsize + 1;
1934         }
1935
1936         if (opts->nr_io_queues) {
1937                 ret = nvme_rdma_configure_io_queues(ctrl, true);
1938                 if (ret)
1939                         goto out_remove_admin_queue;
1940         }
1941
1942         changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
1943         WARN_ON_ONCE(!changed);
1944
1945         dev_info(ctrl->ctrl.device, "new ctrl: NQN \"%s\", addr %pISpcs\n",
1946                 ctrl->ctrl.opts->subsysnqn, &ctrl->addr);
1947
1948         kref_get(&ctrl->ctrl.kref);
1949
1950         mutex_lock(&nvme_rdma_ctrl_mutex);
1951         list_add_tail(&ctrl->list, &nvme_rdma_ctrl_list);
1952         mutex_unlock(&nvme_rdma_ctrl_mutex);
1953
1954         nvme_start_ctrl(&ctrl->ctrl);
1955
1956         return &ctrl->ctrl;
1957
1958 out_remove_admin_queue:
1959         nvme_rdma_destroy_admin_queue(ctrl, true);
1960 out_kfree_queues:
1961         kfree(ctrl->queues);
1962 out_uninit_ctrl:
1963         nvme_uninit_ctrl(&ctrl->ctrl);
1964         nvme_put_ctrl(&ctrl->ctrl);
1965         if (ret > 0)
1966                 ret = -EIO;
1967         return ERR_PTR(ret);
1968 out_free_ctrl:
1969         kfree(ctrl);
1970         return ERR_PTR(ret);
1971 }
1972
1973 static struct nvmf_transport_ops nvme_rdma_transport = {
1974         .name           = "rdma",
1975         .required_opts  = NVMF_OPT_TRADDR,
1976         .allowed_opts   = NVMF_OPT_TRSVCID | NVMF_OPT_RECONNECT_DELAY |
1977                           NVMF_OPT_HOST_TRADDR | NVMF_OPT_CTRL_LOSS_TMO,
1978         .create_ctrl    = nvme_rdma_create_ctrl,
1979 };
1980
1981 static void nvme_rdma_remove_one(struct ib_device *ib_device, void *client_data)
1982 {
1983         struct nvme_rdma_ctrl *ctrl;
1984
1985         /* Delete all controllers using this device */
1986         mutex_lock(&nvme_rdma_ctrl_mutex);
1987         list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list) {
1988                 if (ctrl->device->dev != ib_device)
1989                         continue;
1990                 dev_info(ctrl->ctrl.device,
1991                         "Removing ctrl: NQN \"%s\", addr %pISp\n",
1992                         ctrl->ctrl.opts->subsysnqn, &ctrl->addr);
1993                 __nvme_rdma_del_ctrl(ctrl);
1994         }
1995         mutex_unlock(&nvme_rdma_ctrl_mutex);
1996
1997         flush_workqueue(nvme_wq);
1998 }
1999
2000 static struct ib_client nvme_rdma_ib_client = {
2001         .name   = "nvme_rdma",
2002         .remove = nvme_rdma_remove_one
2003 };
2004
2005 static int __init nvme_rdma_init_module(void)
2006 {
2007         int ret;
2008
2009         ret = ib_register_client(&nvme_rdma_ib_client);
2010         if (ret)
2011                 return ret;
2012
2013         ret = nvmf_register_transport(&nvme_rdma_transport);
2014         if (ret)
2015                 goto err_unreg_client;
2016
2017         return 0;
2018
2019 err_unreg_client:
2020         ib_unregister_client(&nvme_rdma_ib_client);
2021         return ret;
2022 }
2023
2024 static void __exit nvme_rdma_cleanup_module(void)
2025 {
2026         nvmf_unregister_transport(&nvme_rdma_transport);
2027         ib_unregister_client(&nvme_rdma_ib_client);
2028 }
2029
2030 module_init(nvme_rdma_init_module);
2031 module_exit(nvme_rdma_cleanup_module);
2032
2033 MODULE_LICENSE("GPL v2");