drivers/nvme/target/rdma.c

   1 /*
   2  * NVMe over Fabrics RDMA target.
   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/atomic.h>
  16 #include <linux/ctype.h>
  17 #include <linux/delay.h>
  18 #include <linux/err.h>
  19 #include <linux/init.h>
  20 #include <linux/module.h>
  21 #include <linux/nvme.h>
  22 #include <linux/slab.h>
  23 #include <linux/string.h>
  24 #include <linux/wait.h>
  25 #include <linux/inet.h>
  26 #include <asm/unaligned.h>
  27
  28 #include <rdma/ib_verbs.h>
  29 #include <rdma/rdma_cm.h>
  30 #include <rdma/rw.h>
  31
  32 #include <linux/nvme-rdma.h>
  33 #include "nvmet.h"
  34
  35 /*
  36  * We allow up to a page of inline data to go with the SQE
  37  */
  38 #define NVMET_RDMA_INLINE_DATA_SIZE     PAGE_SIZE
  39
  40 struct nvmet_rdma_cmd {
  41         struct ib_sge           sge[2];
  42         struct ib_cqe           cqe;
  43         struct ib_recv_wr       wr;
  44         struct scatterlist      inline_sg;
  45         struct page             *inline_page;
  46         struct nvme_command     *nvme_cmd;
  47         struct nvmet_rdma_queue *queue;
  48 };
  49
  50 enum {
  51         NVMET_RDMA_REQ_INLINE_DATA      = (1 << 0),
  52         NVMET_RDMA_REQ_INVALIDATE_RKEY  = (1 << 1),
  53 };
  54
  55 struct nvmet_rdma_rsp {
  56         struct ib_sge           send_sge;
  57         struct ib_cqe           send_cqe;
  58         struct ib_send_wr       send_wr;
  59
  60         struct nvmet_rdma_cmd   *cmd;
  61         struct nvmet_rdma_queue *queue;
  62
  63         struct ib_cqe           read_cqe;
  64         struct rdma_rw_ctx      rw;
  65
  66         struct nvmet_req        req;
  67
  68         u8                      n_rdma;
  69         u32                     flags;
  70         u32                     invalidate_rkey;
  71
  72         struct list_head        wait_list;
  73         struct list_head        free_list;
  74 };
  75
  76 enum nvmet_rdma_queue_state {
  77         NVMET_RDMA_Q_CONNECTING,
  78         NVMET_RDMA_Q_LIVE,
  79         NVMET_RDMA_Q_DISCONNECTING,
  80 };
  81
  82 struct nvmet_rdma_queue {
  83         struct rdma_cm_id       *cm_id;
  84         struct nvmet_port       *port;
  85         struct ib_cq            *cq;
  86         atomic_t                sq_wr_avail;
  87         struct nvmet_rdma_device *dev;
  88         spinlock_t              state_lock;
  89         enum nvmet_rdma_queue_state state;
  90         struct nvmet_cq         nvme_cq;
  91         struct nvmet_sq         nvme_sq;
  92
  93         struct nvmet_rdma_rsp   *rsps;
  94         struct list_head        free_rsps;
  95         spinlock_t              rsps_lock;
  96         struct nvmet_rdma_cmd   *cmds;
  97
  98         struct work_struct      release_work;
  99         struct list_head        rsp_wait_list;
 100         struct list_head        rsp_wr_wait_list;
 101         spinlock_t              rsp_wr_wait_lock;
 102
 103         int                     idx;
 104         int                     host_qid;
 105         int                     recv_queue_size;
 106         int                     send_queue_size;
 107
 108         struct list_head        queue_list;
 109 };
 110
 111 struct nvmet_rdma_device {
 112         struct ib_device        *device;
 113         struct ib_pd            *pd;
 114         struct ib_srq           *srq;
 115         struct nvmet_rdma_cmd   *srq_cmds;
 116         size_t                  srq_size;
 117         struct kref             ref;
 118         struct list_head        entry;
 119 };
 120
 121 static bool nvmet_rdma_use_srq;
 122 module_param_named(use_srq, nvmet_rdma_use_srq, bool, 0444);
 123 MODULE_PARM_DESC(use_srq, "Use shared receive queue.");
 124
 125 static DEFINE_IDA(nvmet_rdma_queue_ida);
 126 static LIST_HEAD(nvmet_rdma_queue_list);
 127 static DEFINE_MUTEX(nvmet_rdma_queue_mutex);
 128
 129 static LIST_HEAD(device_list);
 130 static DEFINE_MUTEX(device_list_mutex);
 131
 132 static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp);
 133 static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc);
 134 static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
 135 static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc);
 136 static void nvmet_rdma_qp_event(struct ib_event *event, void *priv);
 137 static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue);
 138
 139 static const struct nvmet_fabrics_ops nvmet_rdma_ops;
 140
 141 /* XXX: really should move to a generic header sooner or later.. */
 142 static inline u32 get_unaligned_le24(const u8 *p)
 143 {
 144         return (u32)p[0] | (u32)p[1] << 8 | (u32)p[2] << 16;
 145 }
 146
 147 static inline bool nvmet_rdma_need_data_in(struct nvmet_rdma_rsp *rsp)
 148 {
 149         return nvme_is_write(rsp->req.cmd) &&
 150                 rsp->req.transfer_len &&
 151                 !(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA);
 152 }
 153
 154 static inline bool nvmet_rdma_need_data_out(struct nvmet_rdma_rsp *rsp)
 155 {
 156         return !nvme_is_write(rsp->req.cmd) &&
 157                 rsp->req.transfer_len &&
 158                 !rsp->req.rsp->status &&
 159                 !(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA);
 160 }
 161
 162 static inline struct nvmet_rdma_rsp *
 163 nvmet_rdma_get_rsp(struct nvmet_rdma_queue *queue)
 164 {
 165         struct nvmet_rdma_rsp *rsp;
 166         unsigned long flags;
 167
 168         spin_lock_irqsave(&queue->rsps_lock, flags);
 169         rsp = list_first_entry(&queue->free_rsps,
 170                                 struct nvmet_rdma_rsp, free_list);
 171         list_del(&rsp->free_list);
 172         spin_unlock_irqrestore(&queue->rsps_lock, flags);
 173
 174         return rsp;
 175 }
 176
 177 static inline void
 178 nvmet_rdma_put_rsp(struct nvmet_rdma_rsp *rsp)
 179 {
 180         unsigned long flags;
 181
 182         spin_lock_irqsave(&rsp->queue->rsps_lock, flags);
 183         list_add_tail(&rsp->free_list, &rsp->queue->free_rsps);
 184         spin_unlock_irqrestore(&rsp->queue->rsps_lock, flags);
 185 }
 186
 187 static int nvmet_rdma_alloc_cmd(struct nvmet_rdma_device *ndev,
 188                         struct nvmet_rdma_cmd *c, bool admin)
 189 {
 190         /* NVMe command / RDMA RECV */
 191         c->nvme_cmd = kmalloc(sizeof(*c->nvme_cmd), GFP_KERNEL);
 192         if (!c->nvme_cmd)
 193                 goto out;
 194
 195         c->sge[0].addr = ib_dma_map_single(ndev->device, c->nvme_cmd,
 196                         sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
 197         if (ib_dma_mapping_error(ndev->device, c->sge[0].addr))
 198                 goto out_free_cmd;
 199
 200         c->sge[0].length = sizeof(*c->nvme_cmd);
 201         c->sge[0].lkey = ndev->pd->local_dma_lkey;
 202
 203         if (!admin) {
 204                 c->inline_page = alloc_pages(GFP_KERNEL,
 205                                 get_order(NVMET_RDMA_INLINE_DATA_SIZE));
 206                 if (!c->inline_page)
 207                         goto out_unmap_cmd;
 208                 c->sge[1].addr = ib_dma_map_page(ndev->device,
 209                                 c->inline_page, 0, NVMET_RDMA_INLINE_DATA_SIZE,
 210                                 DMA_FROM_DEVICE);
 211                 if (ib_dma_mapping_error(ndev->device, c->sge[1].addr))
 212                         goto out_free_inline_page;
 213                 c->sge[1].length = NVMET_RDMA_INLINE_DATA_SIZE;
 214                 c->sge[1].lkey = ndev->pd->local_dma_lkey;
 215         }
 216
 217         c->cqe.done = nvmet_rdma_recv_done;
 218
 219         c->wr.wr_cqe = &c->cqe;
 220         c->wr.sg_list = c->sge;
 221         c->wr.num_sge = admin ? 1 : 2;
 222
 223         return 0;
 224
 225 out_free_inline_page:
 226         if (!admin) {
 227                 __free_pages(c->inline_page,
 228                                 get_order(NVMET_RDMA_INLINE_DATA_SIZE));
 229         }
 230 out_unmap_cmd:
 231         ib_dma_unmap_single(ndev->device, c->sge[0].addr,
 232                         sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
 233 out_free_cmd:
 234         kfree(c->nvme_cmd);
 235
 236 out:
 237         return -ENOMEM;
 238 }
 239
 240 static void nvmet_rdma_free_cmd(struct nvmet_rdma_device *ndev,
 241                 struct nvmet_rdma_cmd *c, bool admin)
 242 {
 243         if (!admin) {
 244                 ib_dma_unmap_page(ndev->device, c->sge[1].addr,
 245                                 NVMET_RDMA_INLINE_DATA_SIZE, DMA_FROM_DEVICE);
 246                 __free_pages(c->inline_page,
 247                                 get_order(NVMET_RDMA_INLINE_DATA_SIZE));
 248         }
 249         ib_dma_unmap_single(ndev->device, c->sge[0].addr,
 250                                 sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
 251         kfree(c->nvme_cmd);
 252 }
 253
 254 static struct nvmet_rdma_cmd *
 255 nvmet_rdma_alloc_cmds(struct nvmet_rdma_device *ndev,
 256                 int nr_cmds, bool admin)
 257 {
 258         struct nvmet_rdma_cmd *cmds;
 259         int ret = -EINVAL, i;
 260
 261         cmds = kcalloc(nr_cmds, sizeof(struct nvmet_rdma_cmd), GFP_KERNEL);
 262         if (!cmds)
 263                 goto out;
 264
 265         for (i = 0; i < nr_cmds; i++) {
 266                 ret = nvmet_rdma_alloc_cmd(ndev, cmds + i, admin);
 267                 if (ret)
 268                         goto out_free;
 269         }
 270
 271         return cmds;
 272
 273 out_free:
 274         while (--i >= 0)
 275                 nvmet_rdma_free_cmd(ndev, cmds + i, admin);
 276         kfree(cmds);
 277 out:
 278         return ERR_PTR(ret);
 279 }
 280
 281 static void nvmet_rdma_free_cmds(struct nvmet_rdma_device *ndev,
 282                 struct nvmet_rdma_cmd *cmds, int nr_cmds, bool admin)
 283 {
 284         int i;
 285
 286         for (i = 0; i < nr_cmds; i++)
 287                 nvmet_rdma_free_cmd(ndev, cmds + i, admin);
 288         kfree(cmds);
 289 }
 290
 291 static int nvmet_rdma_alloc_rsp(struct nvmet_rdma_device *ndev,
 292                 struct nvmet_rdma_rsp *r)
 293 {
 294         /* NVMe CQE / RDMA SEND */
 295         r->req.rsp = kmalloc(sizeof(*r->req.rsp), GFP_KERNEL);
 296         if (!r->req.rsp)
 297                 goto out;
 298
 299         r->send_sge.addr = ib_dma_map_single(ndev->device, r->req.rsp,
 300                         sizeof(*r->req.rsp), DMA_TO_DEVICE);
 301         if (ib_dma_mapping_error(ndev->device, r->send_sge.addr))
 302                 goto out_free_rsp;
 303
 304         r->send_sge.length = sizeof(*r->req.rsp);
 305         r->send_sge.lkey = ndev->pd->local_dma_lkey;
 306
 307         r->send_cqe.done = nvmet_rdma_send_done;
 308
 309         r->send_wr.wr_cqe = &r->send_cqe;
 310         r->send_wr.sg_list = &r->send_sge;
 311         r->send_wr.num_sge = 1;
 312         r->send_wr.send_flags = IB_SEND_SIGNALED;
 313
 314         /* Data In / RDMA READ */
 315         r->read_cqe.done = nvmet_rdma_read_data_done;
 316         return 0;
 317
 318 out_free_rsp:
 319         kfree(r->req.rsp);
 320 out:
 321         return -ENOMEM;
 322 }
 323
 324 static void nvmet_rdma_free_rsp(struct nvmet_rdma_device *ndev,
 325                 struct nvmet_rdma_rsp *r)
 326 {
 327         ib_dma_unmap_single(ndev->device, r->send_sge.addr,
 328                                 sizeof(*r->req.rsp), DMA_TO_DEVICE);
 329         kfree(r->req.rsp);
 330 }
 331
 332 static int
 333 nvmet_rdma_alloc_rsps(struct nvmet_rdma_queue *queue)
 334 {
 335         struct nvmet_rdma_device *ndev = queue->dev;
 336         int nr_rsps = queue->recv_queue_size * 2;
 337         int ret = -EINVAL, i;
 338
 339         queue->rsps = kcalloc(nr_rsps, sizeof(struct nvmet_rdma_rsp),
 340                         GFP_KERNEL);
 341         if (!queue->rsps)
 342                 goto out;
 343
 344         for (i = 0; i < nr_rsps; i++) {
 345                 struct nvmet_rdma_rsp *rsp = &queue->rsps[i];
 346
 347                 ret = nvmet_rdma_alloc_rsp(ndev, rsp);
 348                 if (ret)
 349                         goto out_free;
 350
 351                 list_add_tail(&rsp->free_list, &queue->free_rsps);
 352         }
 353
 354         return 0;
 355
 356 out_free:
 357         while (--i >= 0) {
 358                 struct nvmet_rdma_rsp *rsp = &queue->rsps[i];
 359
 360                 list_del(&rsp->free_list);
 361                 nvmet_rdma_free_rsp(ndev, rsp);
 362         }
 363         kfree(queue->rsps);
 364 out:
 365         return ret;
 366 }
 367
 368 static void nvmet_rdma_free_rsps(struct nvmet_rdma_queue *queue)
 369 {
 370         struct nvmet_rdma_device *ndev = queue->dev;
 371         int i, nr_rsps = queue->recv_queue_size * 2;
 372
 373         for (i = 0; i < nr_rsps; i++) {
 374                 struct nvmet_rdma_rsp *rsp = &queue->rsps[i];
 375
 376                 list_del(&rsp->free_list);
 377                 nvmet_rdma_free_rsp(ndev, rsp);
 378         }
 379         kfree(queue->rsps);
 380 }
 381
 382 static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
 383                 struct nvmet_rdma_cmd *cmd)
 384 {
 385         struct ib_recv_wr *bad_wr;
 386
 387         ib_dma_sync_single_for_device(ndev->device,
 388                 cmd->sge[0].addr, cmd->sge[0].length,
 389                 DMA_FROM_DEVICE);
 390
 391         if (ndev->srq)
 392                 return ib_post_srq_recv(ndev->srq, &cmd->wr, &bad_wr);
 393         return ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, &bad_wr);
 394 }
 395
 396 static void nvmet_rdma_process_wr_wait_list(struct nvmet_rdma_queue *queue)
 397 {
 398         spin_lock(&queue->rsp_wr_wait_lock);
 399         while (!list_empty(&queue->rsp_wr_wait_list)) {
 400                 struct nvmet_rdma_rsp *rsp;
 401                 bool ret;
 402
 403                 rsp = list_entry(queue->rsp_wr_wait_list.next,
 404                                 struct nvmet_rdma_rsp, wait_list);
 405                 list_del(&rsp->wait_list);
 406
 407                 spin_unlock(&queue->rsp_wr_wait_lock);
 408                 ret = nvmet_rdma_execute_command(rsp);
 409                 spin_lock(&queue->rsp_wr_wait_lock);
 410
 411                 if (!ret) {
 412                         list_add(&rsp->wait_list, &queue->rsp_wr_wait_list);
 413                         break;
 414                 }
 415         }
 416         spin_unlock(&queue->rsp_wr_wait_lock);
 417 }
 418
 419
 420 static void nvmet_rdma_release_rsp(struct nvmet_rdma_rsp *rsp)
 421 {
 422         struct nvmet_rdma_queue *queue = rsp->queue;
 423
 424         atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);
 425
 426         if (rsp->n_rdma) {
 427                 rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp,
 428                                 queue->cm_id->port_num, rsp->req.sg,
 429                                 rsp->req.sg_cnt, nvmet_data_dir(&rsp->req));
 430         }
 431
 432         if (rsp->req.sg != &rsp->cmd->inline_sg)
 433                 sgl_free(rsp->req.sg);
 434
 435         if (unlikely(!list_empty_careful(&queue->rsp_wr_wait_list)))
 436                 nvmet_rdma_process_wr_wait_list(queue);
 437
 438         nvmet_rdma_put_rsp(rsp);
 439 }
 440
 441 static void nvmet_rdma_error_comp(struct nvmet_rdma_queue *queue)
 442 {
 443         if (queue->nvme_sq.ctrl) {
 444                 nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl);
 445         } else {
 446                 /*
 447                  * we didn't setup the controller yet in case
 448                  * of admin connect error, just disconnect and
 449                  * cleanup the queue
 450                  */
 451                 nvmet_rdma_queue_disconnect(queue);
 452         }
 453 }
 454
 455 static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
 456 {
 457         struct nvmet_rdma_rsp *rsp =
 458                 container_of(wc->wr_cqe, struct nvmet_rdma_rsp, send_cqe);
 459
 460         nvmet_rdma_release_rsp(rsp);
 461
 462         if (unlikely(wc->status != IB_WC_SUCCESS &&
 463                      wc->status != IB_WC_WR_FLUSH_ERR)) {
 464                 pr_err("SEND for CQE 0x%p failed with status %s (%d).\n",
 465                         wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status);
 466                 nvmet_rdma_error_comp(rsp->queue);
 467         }
 468 }
 469
 470 static void nvmet_rdma_queue_response(struct nvmet_req *req)
 471 {
 472         struct nvmet_rdma_rsp *rsp =
 473                 container_of(req, struct nvmet_rdma_rsp, req);
 474         struct rdma_cm_id *cm_id = rsp->queue->cm_id;
 475         struct ib_send_wr *first_wr, *bad_wr;
 476
 477         if (rsp->flags & NVMET_RDMA_REQ_INVALIDATE_RKEY) {
 478                 rsp->send_wr.opcode = IB_WR_SEND_WITH_INV;
 479                 rsp->send_wr.ex.invalidate_rkey = rsp->invalidate_rkey;
 480         } else {
 481                 rsp->send_wr.opcode = IB_WR_SEND;
 482         }
 483
 484         if (nvmet_rdma_need_data_out(rsp))
 485                 first_wr = rdma_rw_ctx_wrs(&rsp->rw, cm_id->qp,
 486                                 cm_id->port_num, NULL, &rsp->send_wr);
 487         else
 488                 first_wr = &rsp->send_wr;
 489
 490         nvmet_rdma_post_recv(rsp->queue->dev, rsp->cmd);
 491
 492         ib_dma_sync_single_for_device(rsp->queue->dev->device,
 493                 rsp->send_sge.addr, rsp->send_sge.length,
 494                 DMA_TO_DEVICE);
 495
 496         if (ib_post_send(cm_id->qp, first_wr, &bad_wr)) {
 497                 pr_err("sending cmd response failed\n");
 498                 nvmet_rdma_release_rsp(rsp);
 499         }
 500 }
 501
 502 static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc)
 503 {
 504         struct nvmet_rdma_rsp *rsp =
 505                 container_of(wc->wr_cqe, struct nvmet_rdma_rsp, read_cqe);
 506         struct nvmet_rdma_queue *queue = cq->cq_context;
 507
 508         WARN_ON(rsp->n_rdma <= 0);
 509         atomic_add(rsp->n_rdma, &queue->sq_wr_avail);
 510         rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp,
 511                         queue->cm_id->port_num, rsp->req.sg,
 512                         rsp->req.sg_cnt, nvmet_data_dir(&rsp->req));
 513         rsp->n_rdma = 0;
 514
 515         if (unlikely(wc->status != IB_WC_SUCCESS)) {
 516                 nvmet_req_uninit(&rsp->req);
 517                 nvmet_rdma_release_rsp(rsp);
 518                 if (wc->status != IB_WC_WR_FLUSH_ERR) {
 519                         pr_info("RDMA READ for CQE 0x%p failed with status %s (%d).\n",
 520                                 wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status);
 521                         nvmet_rdma_error_comp(queue);
 522                 }
 523                 return;
 524         }
 525
 526         nvmet_req_execute(&rsp->req);
 527 }
 528
 529 static void nvmet_rdma_use_inline_sg(struct nvmet_rdma_rsp *rsp, u32 len,
 530                 u64 off)
 531 {
 532         sg_init_table(&rsp->cmd->inline_sg, 1);
 533         sg_set_page(&rsp->cmd->inline_sg, rsp->cmd->inline_page, len, off);
 534         rsp->req.sg = &rsp->cmd->inline_sg;
 535         rsp->req.sg_cnt = 1;
 536 }
 537
 538 static u16 nvmet_rdma_map_sgl_inline(struct nvmet_rdma_rsp *rsp)
 539 {
 540         struct nvme_sgl_desc *sgl = &rsp->req.cmd->common.dptr.sgl;
 541         u64 off = le64_to_cpu(sgl->addr);
 542         u32 len = le32_to_cpu(sgl->length);
 543
 544         if (!nvme_is_write(rsp->req.cmd))
 545                 return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 546
 547         if (off + len > NVMET_RDMA_INLINE_DATA_SIZE) {
 548                 pr_err("invalid inline data offset!\n");
 549                 return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR;
 550         }
 551
 552         /* no data command? */
 553         if (!len)
 554                 return 0;
 555
 556         nvmet_rdma_use_inline_sg(rsp, len, off);
 557         rsp->flags |= NVMET_RDMA_REQ_INLINE_DATA;
 558         rsp->req.transfer_len += len;
 559         return 0;
 560 }
 561
 562 static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
 563                 struct nvme_keyed_sgl_desc *sgl, bool invalidate)
 564 {
 565         struct rdma_cm_id *cm_id = rsp->queue->cm_id;
 566         u64 addr = le64_to_cpu(sgl->addr);
 567         u32 len = get_unaligned_le24(sgl->length);
 568         u32 key = get_unaligned_le32(sgl->key);
 569         int ret;
 570
 571         /* no data command? */
 572         if (!len)
 573                 return 0;
 574
 575         rsp->req.sg = sgl_alloc(len, GFP_KERNEL, &rsp->req.sg_cnt);
 576         if (!rsp->req.sg)
 577                 return NVME_SC_INTERNAL;
 578
 579         ret = rdma_rw_ctx_init(&rsp->rw, cm_id->qp, cm_id->port_num,
 580                         rsp->req.sg, rsp->req.sg_cnt, 0, addr, key,
 581                         nvmet_data_dir(&rsp->req));
 582         if (ret < 0)
 583                 return NVME_SC_INTERNAL;
 584         rsp->req.transfer_len += len;
 585         rsp->n_rdma += ret;
 586
 587         if (invalidate) {
 588                 rsp->invalidate_rkey = key;
 589                 rsp->flags |= NVMET_RDMA_REQ_INVALIDATE_RKEY;
 590         }
 591
 592         return 0;
 593 }
 594
 595 static u16 nvmet_rdma_map_sgl(struct nvmet_rdma_rsp *rsp)
 596 {
 597         struct nvme_keyed_sgl_desc *sgl = &rsp->req.cmd->common.dptr.ksgl;
 598
 599         switch (sgl->type >> 4) {
 600         case NVME_SGL_FMT_DATA_DESC:
 601                 switch (sgl->type & 0xf) {
 602                 case NVME_SGL_FMT_OFFSET:
 603                         return nvmet_rdma_map_sgl_inline(rsp);
 604                 default:
 605                         pr_err("invalid SGL subtype: %#x\n", sgl->type);
 606                         return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 607                 }
 608         case NVME_KEY_SGL_FMT_DATA_DESC:
 609                 switch (sgl->type & 0xf) {
 610                 case NVME_SGL_FMT_ADDRESS | NVME_SGL_FMT_INVALIDATE:
 611                         return nvmet_rdma_map_sgl_keyed(rsp, sgl, true);
 612                 case NVME_SGL_FMT_ADDRESS:
 613                         return nvmet_rdma_map_sgl_keyed(rsp, sgl, false);
 614                 default:
 615                         pr_err("invalid SGL subtype: %#x\n", sgl->type);
 616                         return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
 617                 }
 618         default:
 619                 pr_err("invalid SGL type: %#x\n", sgl->type);
 620                 return NVME_SC_SGL_INVALID_TYPE | NVME_SC_DNR;
 621         }
 622 }
 623
 624 static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp)
 625 {
 626         struct nvmet_rdma_queue *queue = rsp->queue;
 627
 628         if (unlikely(atomic_sub_return(1 + rsp->n_rdma,
 629                         &queue->sq_wr_avail) < 0)) {
 630                 pr_debug("IB send queue full (needed %d): queue %u cntlid %u\n",
 631                                 1 + rsp->n_rdma, queue->idx,
 632                                 queue->nvme_sq.ctrl->cntlid);
 633                 atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);
 634                 return false;
 635         }
 636
 637         if (nvmet_rdma_need_data_in(rsp)) {
 638                 if (rdma_rw_ctx_post(&rsp->rw, queue->cm_id->qp,
 639                                 queue->cm_id->port_num, &rsp->read_cqe, NULL))
 640                         nvmet_req_complete(&rsp->req, NVME_SC_DATA_XFER_ERROR);
 641         } else {
 642                 nvmet_req_execute(&rsp->req);
 643         }
 644
 645         return true;
 646 }
 647
 648 static void nvmet_rdma_handle_command(struct nvmet_rdma_queue *queue,
 649                 struct nvmet_rdma_rsp *cmd)
 650 {
 651         u16 status;
 652
 653         ib_dma_sync_single_for_cpu(queue->dev->device,
 654                 cmd->cmd->sge[0].addr, cmd->cmd->sge[0].length,
 655                 DMA_FROM_DEVICE);
 656         ib_dma_sync_single_for_cpu(queue->dev->device,
 657                 cmd->send_sge.addr, cmd->send_sge.length,
 658                 DMA_TO_DEVICE);
 659
 660         if (!nvmet_req_init(&cmd->req, &queue->nvme_cq,
 661                         &queue->nvme_sq, &nvmet_rdma_ops))
 662                 return;
 663
 664         status = nvmet_rdma_map_sgl(cmd);
 665         if (status)
 666                 goto out_err;
 667
 668         if (unlikely(!nvmet_rdma_execute_command(cmd))) {
 669                 spin_lock(&queue->rsp_wr_wait_lock);
 670                 list_add_tail(&cmd->wait_list, &queue->rsp_wr_wait_list);
 671                 spin_unlock(&queue->rsp_wr_wait_lock);
 672         }
 673
 674         return;
 675
 676 out_err:
 677         nvmet_req_complete(&cmd->req, status);
 678 }
 679
 680 static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
 681 {
 682         struct nvmet_rdma_cmd *cmd =
 683                 container_of(wc->wr_cqe, struct nvmet_rdma_cmd, cqe);
 684         struct nvmet_rdma_queue *queue = cq->cq_context;
 685         struct nvmet_rdma_rsp *rsp;
 686
 687         if (unlikely(wc->status != IB_WC_SUCCESS)) {
 688                 if (wc->status != IB_WC_WR_FLUSH_ERR) {
 689                         pr_err("RECV for CQE 0x%p failed with status %s (%d)\n",
 690                                 wc->wr_cqe, ib_wc_status_msg(wc->status),
 691                                 wc->status);
 692                         nvmet_rdma_error_comp(queue);
 693                 }
 694                 return;
 695         }
 696
 697         if (unlikely(wc->byte_len < sizeof(struct nvme_command))) {
 698                 pr_err("Ctrl Fatal Error: capsule size less than 64 bytes\n");
 699                 nvmet_rdma_error_comp(queue);
 700                 return;
 701         }
 702
 703         cmd->queue = queue;
 704         rsp = nvmet_rdma_get_rsp(queue);
 705         rsp->queue = queue;
 706         rsp->cmd = cmd;
 707         rsp->flags = 0;
 708         rsp->req.cmd = cmd->nvme_cmd;
 709         rsp->req.port = queue->port;
 710         rsp->n_rdma = 0;
 711
 712         if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) {
 713                 unsigned long flags;
 714
 715                 spin_lock_irqsave(&queue->state_lock, flags);
 716                 if (queue->state == NVMET_RDMA_Q_CONNECTING)
 717                         list_add_tail(&rsp->wait_list, &queue->rsp_wait_list);
 718                 else
 719                         nvmet_rdma_put_rsp(rsp);
 720                 spin_unlock_irqrestore(&queue->state_lock, flags);
 721                 return;
 722         }
 723
 724         nvmet_rdma_handle_command(queue, rsp);
 725 }
 726
 727 static void nvmet_rdma_destroy_srq(struct nvmet_rdma_device *ndev)
 728 {
 729         if (!ndev->srq)
 730                 return;
 731
 732         nvmet_rdma_free_cmds(ndev, ndev->srq_cmds, ndev->srq_size, false);
 733         ib_destroy_srq(ndev->srq);
 734 }
 735
 736 static int nvmet_rdma_init_srq(struct nvmet_rdma_device *ndev)
 737 {
 738         struct ib_srq_init_attr srq_attr = { NULL, };
 739         struct ib_srq *srq;
 740         size_t srq_size;
 741         int ret, i;
 742
 743         srq_size = 4095;        /* XXX: tune */
 744
 745         srq_attr.attr.max_wr = srq_size;
 746         srq_attr.attr.max_sge = 2;
 747         srq_attr.attr.srq_limit = 0;
 748         srq_attr.srq_type = IB_SRQT_BASIC;
 749         srq = ib_create_srq(ndev->pd, &srq_attr);
 750         if (IS_ERR(srq)) {
 751                 /*
 752                  * If SRQs aren't supported we just go ahead and use normal
 753                  * non-shared receive queues.
 754                  */
 755                 pr_info("SRQ requested but not supported.\n");
 756                 return 0;
 757         }
 758
 759         ndev->srq_cmds = nvmet_rdma_alloc_cmds(ndev, srq_size, false);
 760         if (IS_ERR(ndev->srq_cmds)) {
 761                 ret = PTR_ERR(ndev->srq_cmds);
 762                 goto out_destroy_srq;
 763         }
 764
 765         ndev->srq = srq;
 766         ndev->srq_size = srq_size;
 767
 768         for (i = 0; i < srq_size; i++)
 769                 nvmet_rdma_post_recv(ndev, &ndev->srq_cmds[i]);
 770
 771         return 0;
 772
 773 out_destroy_srq:
 774         ib_destroy_srq(srq);
 775         return ret;
 776 }
 777
 778 static void nvmet_rdma_free_dev(struct kref *ref)
 779 {
 780         struct nvmet_rdma_device *ndev =
 781                 container_of(ref, struct nvmet_rdma_device, ref);
 782
 783         mutex_lock(&device_list_mutex);
 784         list_del(&ndev->entry);
 785         mutex_unlock(&device_list_mutex);
 786
 787         nvmet_rdma_destroy_srq(ndev);
 788         ib_dealloc_pd(ndev->pd);
 789
 790         kfree(ndev);
 791 }
 792
 793 static struct nvmet_rdma_device *
 794 nvmet_rdma_find_get_device(struct rdma_cm_id *cm_id)
 795 {
 796         struct nvmet_rdma_device *ndev;
 797         int ret;
 798
 799         mutex_lock(&device_list_mutex);
 800         list_for_each_entry(ndev, &device_list, entry) {
 801                 if (ndev->device->node_guid == cm_id->device->node_guid &&
 802                     kref_get_unless_zero(&ndev->ref))
 803                         goto out_unlock;
 804         }
 805
 806         ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
 807         if (!ndev)
 808                 goto out_err;
 809
 810         ndev->device = cm_id->device;
 811         kref_init(&ndev->ref);
 812
 813         ndev->pd = ib_alloc_pd(ndev->device, 0);
 814         if (IS_ERR(ndev->pd))
 815                 goto out_free_dev;
 816
 817         if (nvmet_rdma_use_srq) {
 818                 ret = nvmet_rdma_init_srq(ndev);
 819                 if (ret)
 820                         goto out_free_pd;
 821         }
 822
 823         list_add(&ndev->entry, &device_list);
 824 out_unlock:
 825         mutex_unlock(&device_list_mutex);
 826         pr_debug("added %s.\n", ndev->device->name);
 827         return ndev;
 828
 829 out_free_pd:
 830         ib_dealloc_pd(ndev->pd);
 831 out_free_dev:
 832         kfree(ndev);
 833 out_err:
 834         mutex_unlock(&device_list_mutex);
 835         return NULL;
 836 }
 837
 838 static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue)
 839 {
 840         struct ib_qp_init_attr qp_attr;
 841         struct nvmet_rdma_device *ndev = queue->dev;
 842         int comp_vector, nr_cqe, ret, i;
 843
 844         /*
 845          * Spread the io queues across completion vectors,
 846          * but still keep all admin queues on vector 0.
 847          */
 848         comp_vector = !queue->host_qid ? 0 :
 849                 queue->idx % ndev->device->num_comp_vectors;
 850
 851         /*
 852          * Reserve CQ slots for RECV + RDMA_READ/RDMA_WRITE + RDMA_SEND.
 853          */
 854         nr_cqe = queue->recv_queue_size + 2 * queue->send_queue_size;
 855
 856         queue->cq = ib_alloc_cq(ndev->device, queue,
 857                         nr_cqe + 1, comp_vector,
 858                         IB_POLL_WORKQUEUE);
 859         if (IS_ERR(queue->cq)) {
 860                 ret = PTR_ERR(queue->cq);
 861                 pr_err("failed to create CQ cqe= %d ret= %d\n",
 862                        nr_cqe + 1, ret);
 863                 goto out;
 864         }
 865
 866         memset(&qp_attr, 0, sizeof(qp_attr));
 867         qp_attr.qp_context = queue;
 868         qp_attr.event_handler = nvmet_rdma_qp_event;
 869         qp_attr.send_cq = queue->cq;
 870         qp_attr.recv_cq = queue->cq;
 871         qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
 872         qp_attr.qp_type = IB_QPT_RC;
 873         /* +1 for drain */
 874         qp_attr.cap.max_send_wr = queue->send_queue_size + 1;
 875         qp_attr.cap.max_rdma_ctxs = queue->send_queue_size;
 876         qp_attr.cap.max_send_sge = max(ndev->device->attrs.max_sge_rd,
 877                                         ndev->device->attrs.max_sge);
 878
 879         if (ndev->srq) {
 880                 qp_attr.srq = ndev->srq;
 881         } else {
 882                 /* +1 for drain */
 883                 qp_attr.cap.max_recv_wr = 1 + queue->recv_queue_size;
 884                 qp_attr.cap.max_recv_sge = 2;
 885         }
 886
 887         ret = rdma_create_qp(queue->cm_id, ndev->pd, &qp_attr);
 888         if (ret) {
 889                 pr_err("failed to create_qp ret= %d\n", ret);
 890                 goto err_destroy_cq;
 891         }
 892
 893         atomic_set(&queue->sq_wr_avail, qp_attr.cap.max_send_wr);
 894
 895         pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n",
 896                  __func__, queue->cq->cqe, qp_attr.cap.max_send_sge,
 897                  qp_attr.cap.max_send_wr, queue->cm_id);
 898
 899         if (!ndev->srq) {
 900                 for (i = 0; i < queue->recv_queue_size; i++) {
 901                         queue->cmds[i].queue = queue;
 902                         nvmet_rdma_post_recv(ndev, &queue->cmds[i]);
 903                 }
 904         }
 905
 906 out:
 907         return ret;
 908
 909 err_destroy_cq:
 910         ib_free_cq(queue->cq);
 911         goto out;
 912 }
 913
 914 static void nvmet_rdma_destroy_queue_ib(struct nvmet_rdma_queue *queue)
 915 {
 916         struct ib_qp *qp = queue->cm_id->qp;
 917
 918         ib_drain_qp(qp);
 919         rdma_destroy_id(queue->cm_id);
 920         ib_destroy_qp(qp);
 921         ib_free_cq(queue->cq);
 922 }
 923
 924 static void nvmet_rdma_free_queue(struct nvmet_rdma_queue *queue)
 925 {
 926         pr_debug("freeing queue %d\n", queue->idx);
 927
 928         nvmet_sq_destroy(&queue->nvme_sq);
 929
 930         nvmet_rdma_destroy_queue_ib(queue);
 931         if (!queue->dev->srq) {
 932                 nvmet_rdma_free_cmds(queue->dev, queue->cmds,
 933                                 queue->recv_queue_size,
 934                                 !queue->host_qid);
 935         }
 936         nvmet_rdma_free_rsps(queue);
 937         ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx);
 938         kfree(queue);
 939 }
 940
 941 static void nvmet_rdma_release_queue_work(struct work_struct *w)
 942 {
 943         struct nvmet_rdma_queue *queue =
 944                 container_of(w, struct nvmet_rdma_queue, release_work);
 945         struct nvmet_rdma_device *dev = queue->dev;
 946
 947         nvmet_rdma_free_queue(queue);
 948
 949         kref_put(&dev->ref, nvmet_rdma_free_dev);
 950 }
 951
 952 static int
 953 nvmet_rdma_parse_cm_connect_req(struct rdma_conn_param *conn,
 954                                 struct nvmet_rdma_queue *queue)
 955 {
 956         struct nvme_rdma_cm_req *req;
 957
 958         req = (struct nvme_rdma_cm_req *)conn->private_data;
 959         if (!req || conn->private_data_len == 0)
 960                 return NVME_RDMA_CM_INVALID_LEN;
 961
 962         if (le16_to_cpu(req->recfmt) != NVME_RDMA_CM_FMT_1_0)
 963                 return NVME_RDMA_CM_INVALID_RECFMT;
 964
 965         queue->host_qid = le16_to_cpu(req->qid);
 966
 967         /*
 968          * req->hsqsize corresponds to our recv queue size plus 1
 969          * req->hrqsize corresponds to our send queue size
 970          */
 971         queue->recv_queue_size = le16_to_cpu(req->hsqsize) + 1;
 972         queue->send_queue_size = le16_to_cpu(req->hrqsize);
 973
 974         if (!queue->host_qid && queue->recv_queue_size > NVME_AQ_DEPTH)
 975                 return NVME_RDMA_CM_INVALID_HSQSIZE;
 976
 977         /* XXX: Should we enforce some kind of max for IO queues? */
 978
 979         return 0;
 980 }
 981
 982 static int nvmet_rdma_cm_reject(struct rdma_cm_id *cm_id,
 983                                 enum nvme_rdma_cm_status status)
 984 {
 985         struct nvme_rdma_cm_rej rej;
 986
 987         pr_debug("rejecting connect request: status %d (%s)\n",
 988                  status, nvme_rdma_cm_msg(status));
 989
 990         rej.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
 991         rej.sts = cpu_to_le16(status);
 992
 993         return rdma_reject(cm_id, (void *)&rej, sizeof(rej));
 994 }
 995
 996 static struct nvmet_rdma_queue *
 997 nvmet_rdma_alloc_queue(struct nvmet_rdma_device *ndev,
 998                 struct rdma_cm_id *cm_id,
 999                 struct rdma_cm_event *event)
1000 {
1001         struct nvmet_rdma_queue *queue;
1002         int ret;
1003
1004         queue = kzalloc(sizeof(*queue), GFP_KERNEL);
1005         if (!queue) {
1006                 ret = NVME_RDMA_CM_NO_RSC;
1007                 goto out_reject;
1008         }
1009
1010         ret = nvmet_sq_init(&queue->nvme_sq);
1011         if (ret) {
1012                 ret = NVME_RDMA_CM_NO_RSC;
1013                 goto out_free_queue;
1014         }
1015
1016         ret = nvmet_rdma_parse_cm_connect_req(&event->param.conn, queue);
1017         if (ret)
1018                 goto out_destroy_sq;
1019
1020         /*
1021          * Schedules the actual release because calling rdma_destroy_id from
1022          * inside a CM callback would trigger a deadlock. (great API design..)
1023          */
1024         INIT_WORK(&queue->release_work, nvmet_rdma_release_queue_work);
1025         queue->dev = ndev;
1026         queue->cm_id = cm_id;
1027
1028         spin_lock_init(&queue->state_lock);
1029         queue->state = NVMET_RDMA_Q_CONNECTING;
1030         INIT_LIST_HEAD(&queue->rsp_wait_list);
1031         INIT_LIST_HEAD(&queue->rsp_wr_wait_list);
1032         spin_lock_init(&queue->rsp_wr_wait_lock);
1033         INIT_LIST_HEAD(&queue->free_rsps);
1034         spin_lock_init(&queue->rsps_lock);
1035         INIT_LIST_HEAD(&queue->queue_list);
1036
1037         queue->idx = ida_simple_get(&nvmet_rdma_queue_ida, 0, 0, GFP_KERNEL);
1038         if (queue->idx < 0) {
1039                 ret = NVME_RDMA_CM_NO_RSC;
1040                 goto out_destroy_sq;
1041         }
1042
1043         ret = nvmet_rdma_alloc_rsps(queue);
1044         if (ret) {
1045                 ret = NVME_RDMA_CM_NO_RSC;
1046                 goto out_ida_remove;
1047         }
1048
1049         if (!ndev->srq) {
1050                 queue->cmds = nvmet_rdma_alloc_cmds(ndev,
1051                                 queue->recv_queue_size,
1052                                 !queue->host_qid);
1053                 if (IS_ERR(queue->cmds)) {
1054                         ret = NVME_RDMA_CM_NO_RSC;
1055                         goto out_free_responses;
1056                 }
1057         }
1058
1059         ret = nvmet_rdma_create_queue_ib(queue);
1060         if (ret) {
1061                 pr_err("%s: creating RDMA queue failed (%d).\n",
1062                         __func__, ret);
1063                 ret = NVME_RDMA_CM_NO_RSC;
1064                 goto out_free_cmds;
1065         }
1066
1067         return queue;
1068
1069 out_free_cmds:
1070         if (!ndev->srq) {
1071                 nvmet_rdma_free_cmds(queue->dev, queue->cmds,
1072                                 queue->recv_queue_size,
1073                                 !queue->host_qid);
1074         }
1075 out_free_responses:
1076         nvmet_rdma_free_rsps(queue);
1077 out_ida_remove:
1078         ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx);
1079 out_destroy_sq:
1080         nvmet_sq_destroy(&queue->nvme_sq);
1081 out_free_queue:
1082         kfree(queue);
1083 out_reject:
1084         nvmet_rdma_cm_reject(cm_id, ret);
1085         return NULL;
1086 }
1087
1088 static void nvmet_rdma_qp_event(struct ib_event *event, void *priv)
1089 {
1090         struct nvmet_rdma_queue *queue = priv;
1091
1092         switch (event->event) {
1093         case IB_EVENT_COMM_EST:
1094                 rdma_notify(queue->cm_id, event->event);
1095                 break;
1096         default:
1097                 pr_err("received IB QP event: %s (%d)\n",
1098                        ib_event_msg(event->event), event->event);
1099                 break;
1100         }
1101 }
1102
1103 static int nvmet_rdma_cm_accept(struct rdma_cm_id *cm_id,
1104                 struct nvmet_rdma_queue *queue,
1105                 struct rdma_conn_param *p)
1106 {
1107         struct rdma_conn_param  param = { };
1108         struct nvme_rdma_cm_rep priv = { };
1109         int ret = -ENOMEM;
1110
1111         param.rnr_retry_count = 7;
1112         param.flow_control = 1;
1113         param.initiator_depth = min_t(u8, p->initiator_depth,
1114                 queue->dev->device->attrs.max_qp_init_rd_atom);
1115         param.private_data = &priv;
1116         param.private_data_len = sizeof(priv);
1117         priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
1118         priv.crqsize = cpu_to_le16(queue->recv_queue_size);
1119
1120         ret = rdma_accept(cm_id, &param);
1121         if (ret)
1122                 pr_err("rdma_accept failed (error code = %d)\n", ret);
1123
1124         return ret;
1125 }
1126
1127 static int nvmet_rdma_queue_connect(struct rdma_cm_id *cm_id,
1128                 struct rdma_cm_event *event)
1129 {
1130         struct nvmet_rdma_device *ndev;
1131         struct nvmet_rdma_queue *queue;
1132         int ret = -EINVAL;
1133
1134         ndev = nvmet_rdma_find_get_device(cm_id);
1135         if (!ndev) {
1136                 nvmet_rdma_cm_reject(cm_id, NVME_RDMA_CM_NO_RSC);
1137                 return -ECONNREFUSED;
1138         }
1139
1140         queue = nvmet_rdma_alloc_queue(ndev, cm_id, event);
1141         if (!queue) {
1142                 ret = -ENOMEM;
1143                 goto put_device;
1144         }
1145         queue->port = cm_id->context;
1146
1147         if (queue->host_qid == 0) {
1148                 /* Let inflight controller teardown complete */
1149                 flush_scheduled_work();
1150         }
1151
1152         ret = nvmet_rdma_cm_accept(cm_id, queue, &event->param.conn);
1153         if (ret) {
1154                 schedule_work(&queue->release_work);
1155                 /* Destroying rdma_cm id is not needed here */
1156                 return 0;
1157         }
1158
1159         mutex_lock(&nvmet_rdma_queue_mutex);
1160         list_add_tail(&queue->queue_list, &nvmet_rdma_queue_list);
1161         mutex_unlock(&nvmet_rdma_queue_mutex);
1162
1163         return 0;
1164
1165 put_device:
1166         kref_put(&ndev->ref, nvmet_rdma_free_dev);
1167
1168         return ret;
1169 }
1170
1171 static void nvmet_rdma_queue_established(struct nvmet_rdma_queue *queue)
1172 {
1173         unsigned long flags;
1174
1175         spin_lock_irqsave(&queue->state_lock, flags);
1176         if (queue->state != NVMET_RDMA_Q_CONNECTING) {
1177                 pr_warn("trying to establish a connected queue\n");
1178                 goto out_unlock;
1179         }
1180         queue->state = NVMET_RDMA_Q_LIVE;
1181
1182         while (!list_empty(&queue->rsp_wait_list)) {
1183                 struct nvmet_rdma_rsp *cmd;
1184
1185                 cmd = list_first_entry(&queue->rsp_wait_list,
1186                                         struct nvmet_rdma_rsp, wait_list);
1187                 list_del(&cmd->wait_list);
1188
1189                 spin_unlock_irqrestore(&queue->state_lock, flags);
1190                 nvmet_rdma_handle_command(queue, cmd);
1191                 spin_lock_irqsave(&queue->state_lock, flags);
1192         }
1193
1194 out_unlock:
1195         spin_unlock_irqrestore(&queue->state_lock, flags);
1196 }
1197
1198 static void __nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
1199 {
1200         bool disconnect = false;
1201         unsigned long flags;
1202
1203         pr_debug("cm_id= %p queue->state= %d\n", queue->cm_id, queue->state);
1204
1205         spin_lock_irqsave(&queue->state_lock, flags);
1206         switch (queue->state) {
1207         case NVMET_RDMA_Q_CONNECTING:
1208         case NVMET_RDMA_Q_LIVE:
1209                 queue->state = NVMET_RDMA_Q_DISCONNECTING;
1210                 disconnect = true;
1211                 break;
1212         case NVMET_RDMA_Q_DISCONNECTING:
1213                 break;
1214         }
1215         spin_unlock_irqrestore(&queue->state_lock, flags);
1216
1217         if (disconnect) {
1218                 rdma_disconnect(queue->cm_id);
1219                 schedule_work(&queue->release_work);
1220         }
1221 }
1222
1223 static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
1224 {
1225         bool disconnect = false;
1226
1227         mutex_lock(&nvmet_rdma_queue_mutex);
1228         if (!list_empty(&queue->queue_list)) {
1229                 list_del_init(&queue->queue_list);
1230                 disconnect = true;
1231         }
1232         mutex_unlock(&nvmet_rdma_queue_mutex);
1233
1234         if (disconnect)
1235                 __nvmet_rdma_queue_disconnect(queue);
1236 }
1237
1238 static void nvmet_rdma_queue_connect_fail(struct rdma_cm_id *cm_id,
1239                 struct nvmet_rdma_queue *queue)
1240 {
1241         WARN_ON_ONCE(queue->state != NVMET_RDMA_Q_CONNECTING);
1242
1243         mutex_lock(&nvmet_rdma_queue_mutex);
1244         if (!list_empty(&queue->queue_list))
1245                 list_del_init(&queue->queue_list);
1246         mutex_unlock(&nvmet_rdma_queue_mutex);
1247
1248         pr_err("failed to connect queue %d\n", queue->idx);
1249         schedule_work(&queue->release_work);
1250 }
1251
1252 /**
1253  * nvme_rdma_device_removal() - Handle RDMA device removal
1254  * @cm_id:      rdma_cm id, used for nvmet port
1255  * @queue:      nvmet rdma queue (cm id qp_context)
1256  *
1257  * DEVICE_REMOVAL event notifies us that the RDMA device is about
1258  * to unplug. Note that this event can be generated on a normal
1259  * queue cm_id and/or a device bound listener cm_id (where in this
1260  * case queue will be null).
1261  *
1262  * We registered an ib_client to handle device removal for queues,
1263  * so we only need to handle the listening port cm_ids. In this case
1264  * we nullify the priv to prevent double cm_id destruction and destroying
1265  * the cm_id implicitely by returning a non-zero rc to the callout.
1266  */
1267 static int nvmet_rdma_device_removal(struct rdma_cm_id *cm_id,
1268                 struct nvmet_rdma_queue *queue)
1269 {
1270         struct nvmet_port *port;
1271
1272         if (queue) {
1273                 /*
1274                  * This is a queue cm_id. we have registered
1275                  * an ib_client to handle queues removal
1276                  * so don't interfear and just return.
1277                  */
1278                 return 0;
1279         }
1280
1281         port = cm_id->context;
1282
1283         /*
1284          * This is a listener cm_id. Make sure that
1285          * future remove_port won't invoke a double
1286          * cm_id destroy. use atomic xchg to make sure
1287          * we don't compete with remove_port.
1288          */
1289         if (xchg(&port->priv, NULL) != cm_id)
1290                 return 0;
1291
1292         /*
1293          * We need to return 1 so that the core will destroy
1294          * it's own ID.  What a great API design..
1295          */
1296         return 1;
1297 }
1298
1299 static int nvmet_rdma_cm_handler(struct rdma_cm_id *cm_id,
1300                 struct rdma_cm_event *event)
1301 {
1302         struct nvmet_rdma_queue *queue = NULL;
1303         int ret = 0;
1304
1305         if (cm_id->qp)
1306                 queue = cm_id->qp->qp_context;
1307
1308         pr_debug("%s (%d): status %d id %p\n",
1309                 rdma_event_msg(event->event), event->event,
1310                 event->status, cm_id);
1311
1312         switch (event->event) {
1313         case RDMA_CM_EVENT_CONNECT_REQUEST:
1314                 ret = nvmet_rdma_queue_connect(cm_id, event);
1315                 break;
1316         case RDMA_CM_EVENT_ESTABLISHED:
1317                 nvmet_rdma_queue_established(queue);
1318                 break;
1319         case RDMA_CM_EVENT_ADDR_CHANGE:
1320         case RDMA_CM_EVENT_DISCONNECTED:
1321         case RDMA_CM_EVENT_TIMEWAIT_EXIT:
1322                 nvmet_rdma_queue_disconnect(queue);
1323                 break;
1324         case RDMA_CM_EVENT_DEVICE_REMOVAL:
1325                 ret = nvmet_rdma_device_removal(cm_id, queue);
1326                 break;
1327         case RDMA_CM_EVENT_REJECTED:
1328                 pr_debug("Connection rejected: %s\n",
1329                          rdma_reject_msg(cm_id, event->status));
1330                 /* FALLTHROUGH */
1331         case RDMA_CM_EVENT_UNREACHABLE:
1332         case RDMA_CM_EVENT_CONNECT_ERROR:
1333                 nvmet_rdma_queue_connect_fail(cm_id, queue);
1334                 break;
1335         default:
1336                 pr_err("received unrecognized RDMA CM event %d\n",
1337                         event->event);
1338                 break;
1339         }
1340
1341         return ret;
1342 }
1343
1344 static void nvmet_rdma_delete_ctrl(struct nvmet_ctrl *ctrl)
1345 {
1346         struct nvmet_rdma_queue *queue;
1347
1348 restart:
1349         mutex_lock(&nvmet_rdma_queue_mutex);
1350         list_for_each_entry(queue, &nvmet_rdma_queue_list, queue_list) {
1351                 if (queue->nvme_sq.ctrl == ctrl) {
1352                         list_del_init(&queue->queue_list);
1353                         mutex_unlock(&nvmet_rdma_queue_mutex);
1354
1355                         __nvmet_rdma_queue_disconnect(queue);
1356                         goto restart;
1357                 }
1358         }
1359         mutex_unlock(&nvmet_rdma_queue_mutex);
1360 }
1361
1362 static int nvmet_rdma_add_port(struct nvmet_port *port)
1363 {
1364         struct rdma_cm_id *cm_id;
1365         struct sockaddr_storage addr = { };
1366         __kernel_sa_family_t af;
1367         int ret;
1368
1369         switch (port->disc_addr.adrfam) {
1370         case NVMF_ADDR_FAMILY_IP4:
1371                 af = AF_INET;
1372                 break;
1373         case NVMF_ADDR_FAMILY_IP6:
1374                 af = AF_INET6;
1375                 break;
1376         default:
1377                 pr_err("address family %d not supported\n",
1378                                 port->disc_addr.adrfam);
1379                 return -EINVAL;
1380         }
1381
1382         ret = inet_pton_with_scope(&init_net, af, port->disc_addr.traddr,
1383                         port->disc_addr.trsvcid, &addr);
1384         if (ret) {
1385                 pr_err("malformed ip/port passed: %s:%s\n",
1386                         port->disc_addr.traddr, port->disc_addr.trsvcid);
1387                 return ret;
1388         }
1389
1390         cm_id = rdma_create_id(&init_net, nvmet_rdma_cm_handler, port,
1391                         RDMA_PS_TCP, IB_QPT_RC);
1392         if (IS_ERR(cm_id)) {
1393                 pr_err("CM ID creation failed\n");
1394                 return PTR_ERR(cm_id);
1395         }
1396
1397         /*
1398          * Allow both IPv4 and IPv6 sockets to bind a single port
1399          * at the same time.
1400          */
1401         ret = rdma_set_afonly(cm_id, 1);
1402         if (ret) {
1403                 pr_err("rdma_set_afonly failed (%d)\n", ret);
1404                 goto out_destroy_id;
1405         }
1406
1407         ret = rdma_bind_addr(cm_id, (struct sockaddr *)&addr);
1408         if (ret) {
1409                 pr_err("binding CM ID to %pISpcs failed (%d)\n",
1410                         (struct sockaddr *)&addr, ret);
1411                 goto out_destroy_id;
1412         }
1413
1414         ret = rdma_listen(cm_id, 128);
1415         if (ret) {
1416                 pr_err("listening to %pISpcs failed (%d)\n",
1417                         (struct sockaddr *)&addr, ret);
1418                 goto out_destroy_id;
1419         }
1420
1421         pr_info("enabling port %d (%pISpcs)\n",
1422                 le16_to_cpu(port->disc_addr.portid), (struct sockaddr *)&addr);
1423         port->priv = cm_id;
1424         return 0;
1425
1426 out_destroy_id:
1427         rdma_destroy_id(cm_id);
1428         return ret;
1429 }
1430
1431 static void nvmet_rdma_remove_port(struct nvmet_port *port)
1432 {
1433         struct rdma_cm_id *cm_id = xchg(&port->priv, NULL);
1434
1435         if (cm_id)
1436                 rdma_destroy_id(cm_id);
1437 }
1438
1439 static void nvmet_rdma_disc_port_addr(struct nvmet_req *req,
1440                 struct nvmet_port *port, char *traddr)
1441 {
1442         struct rdma_cm_id *cm_id = port->priv;
1443
1444         if (inet_addr_is_any((struct sockaddr *)&cm_id->route.addr.src_addr)) {
1445                 struct nvmet_rdma_rsp *rsp =
1446                         container_of(req, struct nvmet_rdma_rsp, req);
1447                 struct rdma_cm_id *req_cm_id = rsp->queue->cm_id;
1448                 struct sockaddr *addr = (void *)&req_cm_id->route.addr.src_addr;
1449
1450                 sprintf(traddr, "%pISc", addr);
1451         } else {
1452                 memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
1453         }
1454 }
1455
1456 static const struct nvmet_fabrics_ops nvmet_rdma_ops = {
1457         .owner                  = THIS_MODULE,
1458         .type                   = NVMF_TRTYPE_RDMA,
1459         .sqe_inline_size        = NVMET_RDMA_INLINE_DATA_SIZE,
1460         .msdbd                  = 1,
1461         .has_keyed_sgls         = 1,
1462         .add_port               = nvmet_rdma_add_port,
1463         .remove_port            = nvmet_rdma_remove_port,
1464         .queue_response         = nvmet_rdma_queue_response,
1465         .delete_ctrl            = nvmet_rdma_delete_ctrl,
1466         .disc_traddr            = nvmet_rdma_disc_port_addr,
1467 };
1468
1469 static void nvmet_rdma_remove_one(struct ib_device *ib_device, void *client_data)
1470 {
1471         struct nvmet_rdma_queue *queue, *tmp;
1472         struct nvmet_rdma_device *ndev;
1473         bool found = false;
1474
1475         mutex_lock(&device_list_mutex);
1476         list_for_each_entry(ndev, &device_list, entry) {
1477                 if (ndev->device == ib_device) {
1478                         found = true;
1479                         break;
1480                 }
1481         }
1482         mutex_unlock(&device_list_mutex);
1483
1484         if (!found)
1485                 return;
1486
1487         /*
1488          * IB Device that is used by nvmet controllers is being removed,
1489          * delete all queues using this device.
1490          */
1491         mutex_lock(&nvmet_rdma_queue_mutex);
1492         list_for_each_entry_safe(queue, tmp, &nvmet_rdma_queue_list,
1493                                  queue_list) {
1494                 if (queue->dev->device != ib_device)
1495                         continue;
1496
1497                 pr_info("Removing queue %d\n", queue->idx);
1498                 list_del_init(&queue->queue_list);
1499                 __nvmet_rdma_queue_disconnect(queue);
1500         }
1501         mutex_unlock(&nvmet_rdma_queue_mutex);
1502
1503         flush_scheduled_work();
1504 }
1505
1506 static struct ib_client nvmet_rdma_ib_client = {
1507         .name   = "nvmet_rdma",
1508         .remove = nvmet_rdma_remove_one
1509 };
1510
1511 static int __init nvmet_rdma_init(void)
1512 {
1513         int ret;
1514
1515         ret = ib_register_client(&nvmet_rdma_ib_client);
1516         if (ret)
1517                 return ret;
1518
1519         ret = nvmet_register_transport(&nvmet_rdma_ops);
1520         if (ret)
1521                 goto err_ib_client;
1522
1523         return 0;
1524
1525 err_ib_client:
1526         ib_unregister_client(&nvmet_rdma_ib_client);
1527         return ret;
1528 }
1529
1530 static void __exit nvmet_rdma_exit(void)
1531 {
1532         nvmet_unregister_transport(&nvmet_rdma_ops);
1533         ib_unregister_client(&nvmet_rdma_ib_client);
1534         WARN_ON_ONCE(!list_empty(&nvmet_rdma_queue_list));
1535         ida_destroy(&nvmet_rdma_queue_ida);
1536 }
1537
1538 module_init(nvmet_rdma_init);
1539 module_exit(nvmet_rdma_exit);
1540
1541 MODULE_LICENSE("GPL v2");
1542 MODULE_ALIAS("nvmet-transport-1"); /* 1 == NVMF_TRTYPE_RDMA */