net/smc/smc_wr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  * Work Requests exploiting Infiniband API
   6  *
   7  * Work requests (WR) of type ib_post_send or ib_post_recv respectively
   8  * are submitted to either RC SQ or RC RQ respectively
   9  * (reliably connected send/receive queue)
  10  * and become work queue entries (WQEs).
  11  * While an SQ WR/WQE is pending, we track it until transmission completion.
  12  * Through a send or receive completion queue (CQ) respectively,
  13  * we get completion queue entries (CQEs) [aka work completions (WCs)].
  14  * Since the CQ callback is called from IRQ context, we split work by using
  15  * bottom halves implemented by tasklets.
  16  *
  17  * SMC uses this to exchange LLC (link layer control)
  18  * and CDC (connection data control) messages.
  19  *
  20  * Copyright IBM Corp. 2016
  21  *
  22  * Author(s):  Steffen Maier <[email protected]>
  23  */
  24
  25 #include <linux/atomic.h>
  26 #include <linux/hashtable.h>
  27 #include <linux/wait.h>
  28 #include <rdma/ib_verbs.h>
  29 #include <asm/div64.h>
  30
  31 #include "smc.h"
  32 #include "smc_wr.h"
  33
  34 #define SMC_WR_MAX_POLL_CQE 10  /* max. # of compl. queue elements in 1 poll */
  35
  36 #define SMC_WR_RX_HASH_BITS 4
  37 static DEFINE_HASHTABLE(smc_wr_rx_hash, SMC_WR_RX_HASH_BITS);
  38 static DEFINE_SPINLOCK(smc_wr_rx_hash_lock);
  39
  40 struct smc_wr_tx_pend { /* control data for a pending send request */
  41         u64                     wr_id;          /* work request id sent */
  42         smc_wr_tx_handler       handler;
  43         enum ib_wc_status       wc_status;      /* CQE status */
  44         struct smc_link         *link;
  45         u32                     idx;
  46         struct smc_wr_tx_pend_priv priv;
  47 };
  48
  49 /******************************** send queue *********************************/
  50
  51 /*------------------------------- completion --------------------------------*/
  52
  53 static inline int smc_wr_tx_find_pending_index(struct smc_link *link, u64 wr_id)
  54 {
  55         u32 i;
  56
  57         for (i = 0; i < link->wr_tx_cnt; i++) {
  58                 if (link->wr_tx_pends[i].wr_id == wr_id)
  59                         return i;
  60         }
  61         return link->wr_tx_cnt;
  62 }
  63
  64 static inline void smc_wr_tx_process_cqe(struct ib_wc *wc)
  65 {
  66         struct smc_wr_tx_pend pnd_snd;
  67         struct smc_link *link;
  68         u32 pnd_snd_idx;
  69         int i;
  70
  71         link = wc->qp->qp_context;
  72
  73         if (wc->opcode == IB_WC_REG_MR) {
  74                 if (wc->status)
  75                         link->wr_reg_state = FAILED;
  76                 else
  77                         link->wr_reg_state = CONFIRMED;
  78                 wake_up(&link->wr_reg_wait);
  79                 return;
  80         }
  81
  82         pnd_snd_idx = smc_wr_tx_find_pending_index(link, wc->wr_id);
  83         if (pnd_snd_idx == link->wr_tx_cnt)
  84                 return;
  85         link->wr_tx_pends[pnd_snd_idx].wc_status = wc->status;
  86         memcpy(&pnd_snd, &link->wr_tx_pends[pnd_snd_idx], sizeof(pnd_snd));
  87         /* clear the full struct smc_wr_tx_pend including .priv */
  88         memset(&link->wr_tx_pends[pnd_snd_idx], 0,
  89                sizeof(link->wr_tx_pends[pnd_snd_idx]));
  90         memset(&link->wr_tx_bufs[pnd_snd_idx], 0,
  91                sizeof(link->wr_tx_bufs[pnd_snd_idx]));
  92         if (!test_and_clear_bit(pnd_snd_idx, link->wr_tx_mask))
  93                 return;
  94         if (wc->status) {
  95                 for_each_set_bit(i, link->wr_tx_mask, link->wr_tx_cnt) {
  96                         /* clear full struct smc_wr_tx_pend including .priv */
  97                         memset(&link->wr_tx_pends[i], 0,
  98                                sizeof(link->wr_tx_pends[i]));
  99                         memset(&link->wr_tx_bufs[i], 0,
 100                                sizeof(link->wr_tx_bufs[i]));
 101                         clear_bit(i, link->wr_tx_mask);
 102                 }
 103                 /* terminate connections of this link group abnormally */
 104                 smc_lgr_terminate(smc_get_lgr(link));
 105         }
 106         if (pnd_snd.handler)
 107                 pnd_snd.handler(&pnd_snd.priv, link, wc->status);
 108         wake_up(&link->wr_tx_wait);
 109 }
 110
 111 static void smc_wr_tx_tasklet_fn(unsigned long data)
 112 {
 113         struct smc_ib_device *dev = (struct smc_ib_device *)data;
 114         struct ib_wc wc[SMC_WR_MAX_POLL_CQE];
 115         int i = 0, rc;
 116         int polled = 0;
 117
 118 again:
 119         polled++;
 120         do {
 121                 memset(&wc, 0, sizeof(wc));
 122                 rc = ib_poll_cq(dev->roce_cq_send, SMC_WR_MAX_POLL_CQE, wc);
 123                 if (polled == 1) {
 124                         ib_req_notify_cq(dev->roce_cq_send,
 125                                          IB_CQ_NEXT_COMP |
 126                                          IB_CQ_REPORT_MISSED_EVENTS);
 127                 }
 128                 if (!rc)
 129                         break;
 130                 for (i = 0; i < rc; i++)
 131                         smc_wr_tx_process_cqe(&wc[i]);
 132         } while (rc > 0);
 133         if (polled == 1)
 134                 goto again;
 135 }
 136
 137 void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context)
 138 {
 139         struct smc_ib_device *dev = (struct smc_ib_device *)cq_context;
 140
 141         tasklet_schedule(&dev->send_tasklet);
 142 }
 143
 144 /*---------------------------- request submission ---------------------------*/
 145
 146 static inline int smc_wr_tx_get_free_slot_index(struct smc_link *link, u32 *idx)
 147 {
 148         *idx = link->wr_tx_cnt;
 149         for_each_clear_bit(*idx, link->wr_tx_mask, link->wr_tx_cnt) {
 150                 if (!test_and_set_bit(*idx, link->wr_tx_mask))
 151                         return 0;
 152         }
 153         *idx = link->wr_tx_cnt;
 154         return -EBUSY;
 155 }
 156
 157 /**
 158  * smc_wr_tx_get_free_slot() - returns buffer for message assembly,
 159  *                      and sets info for pending transmit tracking
 160  * @link:               Pointer to smc_link used to later send the message.
 161  * @handler:            Send completion handler function pointer.
 162  * @wr_buf:             Out value returns pointer to message buffer.
 163  * @wr_rdma_buf:        Out value returns pointer to rdma work request.
 164  * @wr_pend_priv:       Out value returns pointer serving as handler context.
 165  *
 166  * Return: 0 on success, or -errno on error.
 167  */
 168 int smc_wr_tx_get_free_slot(struct smc_link *link,
 169                             smc_wr_tx_handler handler,
 170                             struct smc_wr_buf **wr_buf,
 171                             struct smc_rdma_wr **wr_rdma_buf,
 172                             struct smc_wr_tx_pend_priv **wr_pend_priv)
 173 {
 174         struct smc_wr_tx_pend *wr_pend;
 175         u32 idx = link->wr_tx_cnt;
 176         struct ib_send_wr *wr_ib;
 177         u64 wr_id;
 178         int rc;
 179
 180         *wr_buf = NULL;
 181         *wr_pend_priv = NULL;
 182         if (in_softirq()) {
 183                 rc = smc_wr_tx_get_free_slot_index(link, &idx);
 184                 if (rc)
 185                         return rc;
 186         } else {
 187                 rc = wait_event_timeout(
 188                         link->wr_tx_wait,
 189                         link->state == SMC_LNK_INACTIVE ||
 190                         (smc_wr_tx_get_free_slot_index(link, &idx) != -EBUSY),
 191                         SMC_WR_TX_WAIT_FREE_SLOT_TIME);
 192                 if (!rc) {
 193                         /* timeout - terminate connections */
 194                         smc_lgr_terminate(smc_get_lgr(link));
 195                         return -EPIPE;
 196                 }
 197                 if (idx == link->wr_tx_cnt)
 198                         return -EPIPE;
 199         }
 200         wr_id = smc_wr_tx_get_next_wr_id(link);
 201         wr_pend = &link->wr_tx_pends[idx];
 202         wr_pend->wr_id = wr_id;
 203         wr_pend->handler = handler;
 204         wr_pend->link = link;
 205         wr_pend->idx = idx;
 206         wr_ib = &link->wr_tx_ibs[idx];
 207         wr_ib->wr_id = wr_id;
 208         *wr_buf = &link->wr_tx_bufs[idx];
 209         if (wr_rdma_buf)
 210                 *wr_rdma_buf = &link->wr_tx_rdmas[idx];
 211         *wr_pend_priv = &wr_pend->priv;
 212         return 0;
 213 }
 214
 215 int smc_wr_tx_put_slot(struct smc_link *link,
 216                        struct smc_wr_tx_pend_priv *wr_pend_priv)
 217 {
 218         struct smc_wr_tx_pend *pend;
 219
 220         pend = container_of(wr_pend_priv, struct smc_wr_tx_pend, priv);
 221         if (pend->idx < link->wr_tx_cnt) {
 222                 u32 idx = pend->idx;
 223
 224                 /* clear the full struct smc_wr_tx_pend including .priv */
 225                 memset(&link->wr_tx_pends[idx], 0,
 226                        sizeof(link->wr_tx_pends[idx]));
 227                 memset(&link->wr_tx_bufs[idx], 0,
 228                        sizeof(link->wr_tx_bufs[idx]));
 229                 test_and_clear_bit(idx, link->wr_tx_mask);
 230                 return 1;
 231         }
 232
 233         return 0;
 234 }
 235
 236 /* Send prepared WR slot via ib_post_send.
 237  * @priv: pointer to smc_wr_tx_pend_priv identifying prepared message buffer
 238  */
 239 int smc_wr_tx_send(struct smc_link *link, struct smc_wr_tx_pend_priv *priv)
 240 {
 241         struct smc_wr_tx_pend *pend;
 242         int rc;
 243
 244         ib_req_notify_cq(link->smcibdev->roce_cq_send,
 245                          IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
 246         pend = container_of(priv, struct smc_wr_tx_pend, priv);
 247         rc = ib_post_send(link->roce_qp, &link->wr_tx_ibs[pend->idx], NULL);
 248         if (rc) {
 249                 smc_wr_tx_put_slot(link, priv);
 250                 smc_lgr_terminate(smc_get_lgr(link));
 251         }
 252         return rc;
 253 }
 254
 255 /* Register a memory region and wait for result. */
 256 int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr)
 257 {
 258         int rc;
 259
 260         ib_req_notify_cq(link->smcibdev->roce_cq_send,
 261                          IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
 262         link->wr_reg_state = POSTED;
 263         link->wr_reg.wr.wr_id = (u64)(uintptr_t)mr;
 264         link->wr_reg.mr = mr;
 265         link->wr_reg.key = mr->rkey;
 266         rc = ib_post_send(link->roce_qp, &link->wr_reg.wr, NULL);
 267         if (rc)
 268                 return rc;
 269
 270         rc = wait_event_interruptible_timeout(link->wr_reg_wait,
 271                                               (link->wr_reg_state != POSTED),
 272                                               SMC_WR_REG_MR_WAIT_TIME);
 273         if (!rc) {
 274                 /* timeout - terminate connections */
 275                 smc_lgr_terminate(smc_get_lgr(link));
 276                 return -EPIPE;
 277         }
 278         if (rc == -ERESTARTSYS)
 279                 return -EINTR;
 280         switch (link->wr_reg_state) {
 281         case CONFIRMED:
 282                 rc = 0;
 283                 break;
 284         case FAILED:
 285                 rc = -EIO;
 286                 break;
 287         case POSTED:
 288                 rc = -EPIPE;
 289                 break;
 290         }
 291         return rc;
 292 }
 293
 294 void smc_wr_tx_dismiss_slots(struct smc_link *link, u8 wr_tx_hdr_type,
 295                              smc_wr_tx_filter filter,
 296                              smc_wr_tx_dismisser dismisser,
 297                              unsigned long data)
 298 {
 299         struct smc_wr_tx_pend_priv *tx_pend;
 300         struct smc_wr_rx_hdr *wr_tx;
 301         int i;
 302
 303         for_each_set_bit(i, link->wr_tx_mask, link->wr_tx_cnt) {
 304                 wr_tx = (struct smc_wr_rx_hdr *)&link->wr_tx_bufs[i];
 305                 if (wr_tx->type != wr_tx_hdr_type)
 306                         continue;
 307                 tx_pend = &link->wr_tx_pends[i].priv;
 308                 if (filter(tx_pend, data))
 309                         dismisser(tx_pend);
 310         }
 311 }
 312
 313 /****************************** receive queue ********************************/
 314
 315 int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler)
 316 {
 317         struct smc_wr_rx_handler *h_iter;
 318         int rc = 0;
 319
 320         spin_lock(&smc_wr_rx_hash_lock);
 321         hash_for_each_possible(smc_wr_rx_hash, h_iter, list, handler->type) {
 322                 if (h_iter->type == handler->type) {
 323                         rc = -EEXIST;
 324                         goto out_unlock;
 325                 }
 326         }
 327         hash_add(smc_wr_rx_hash, &handler->list, handler->type);
 328 out_unlock:
 329         spin_unlock(&smc_wr_rx_hash_lock);
 330         return rc;
 331 }
 332
 333 /* Demultiplex a received work request based on the message type to its handler.
 334  * Relies on smc_wr_rx_hash having been completely filled before any IB WRs,
 335  * and not being modified any more afterwards so we don't need to lock it.
 336  */
 337 static inline void smc_wr_rx_demultiplex(struct ib_wc *wc)
 338 {
 339         struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
 340         struct smc_wr_rx_handler *handler;
 341         struct smc_wr_rx_hdr *wr_rx;
 342         u64 temp_wr_id;
 343         u32 index;
 344
 345         if (wc->byte_len < sizeof(*wr_rx))
 346                 return; /* short message */
 347         temp_wr_id = wc->wr_id;
 348         index = do_div(temp_wr_id, link->wr_rx_cnt);
 349         wr_rx = (struct smc_wr_rx_hdr *)&link->wr_rx_bufs[index];
 350         hash_for_each_possible(smc_wr_rx_hash, handler, list, wr_rx->type) {
 351                 if (handler->type == wr_rx->type)
 352                         handler->handler(wc, wr_rx);
 353         }
 354 }
 355
 356 static inline void smc_wr_rx_process_cqes(struct ib_wc wc[], int num)
 357 {
 358         struct smc_link *link;
 359         int i;
 360
 361         for (i = 0; i < num; i++) {
 362                 link = wc[i].qp->qp_context;
 363                 if (wc[i].status == IB_WC_SUCCESS) {
 364                         link->wr_rx_tstamp = jiffies;
 365                         smc_wr_rx_demultiplex(&wc[i]);
 366                         smc_wr_rx_post(link); /* refill WR RX */
 367                 } else {
 368                         /* handle status errors */
 369                         switch (wc[i].status) {
 370                         case IB_WC_RETRY_EXC_ERR:
 371                         case IB_WC_RNR_RETRY_EXC_ERR:
 372                         case IB_WC_WR_FLUSH_ERR:
 373                                 /* terminate connections of this link group
 374                                  * abnormally
 375                                  */
 376                                 smc_lgr_terminate(smc_get_lgr(link));
 377                                 break;
 378                         default:
 379                                 smc_wr_rx_post(link); /* refill WR RX */
 380                                 break;
 381                         }
 382                 }
 383         }
 384 }
 385
 386 static void smc_wr_rx_tasklet_fn(unsigned long data)
 387 {
 388         struct smc_ib_device *dev = (struct smc_ib_device *)data;
 389         struct ib_wc wc[SMC_WR_MAX_POLL_CQE];
 390         int polled = 0;
 391         int rc;
 392
 393 again:
 394         polled++;
 395         do {
 396                 memset(&wc, 0, sizeof(wc));
 397                 rc = ib_poll_cq(dev->roce_cq_recv, SMC_WR_MAX_POLL_CQE, wc);
 398                 if (polled == 1) {
 399                         ib_req_notify_cq(dev->roce_cq_recv,
 400                                          IB_CQ_SOLICITED_MASK
 401                                          | IB_CQ_REPORT_MISSED_EVENTS);
 402                 }
 403                 if (!rc)
 404                         break;
 405                 smc_wr_rx_process_cqes(&wc[0], rc);
 406         } while (rc > 0);
 407         if (polled == 1)
 408                 goto again;
 409 }
 410
 411 void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context)
 412 {
 413         struct smc_ib_device *dev = (struct smc_ib_device *)cq_context;
 414
 415         tasklet_schedule(&dev->recv_tasklet);
 416 }
 417
 418 int smc_wr_rx_post_init(struct smc_link *link)
 419 {
 420         u32 i;
 421         int rc = 0;
 422
 423         for (i = 0; i < link->wr_rx_cnt; i++)
 424                 rc = smc_wr_rx_post(link);
 425         return rc;
 426 }
 427
 428 /***************************** init, exit, misc ******************************/
 429
 430 void smc_wr_remember_qp_attr(struct smc_link *lnk)
 431 {
 432         struct ib_qp_attr *attr = &lnk->qp_attr;
 433         struct ib_qp_init_attr init_attr;
 434
 435         memset(attr, 0, sizeof(*attr));
 436         memset(&init_attr, 0, sizeof(init_attr));
 437         ib_query_qp(lnk->roce_qp, attr,
 438                     IB_QP_STATE |
 439                     IB_QP_CUR_STATE |
 440                     IB_QP_PKEY_INDEX |
 441                     IB_QP_PORT |
 442                     IB_QP_QKEY |
 443                     IB_QP_AV |
 444                     IB_QP_PATH_MTU |
 445                     IB_QP_TIMEOUT |
 446                     IB_QP_RETRY_CNT |
 447                     IB_QP_RNR_RETRY |
 448                     IB_QP_RQ_PSN |
 449                     IB_QP_ALT_PATH |
 450                     IB_QP_MIN_RNR_TIMER |
 451                     IB_QP_SQ_PSN |
 452                     IB_QP_PATH_MIG_STATE |
 453                     IB_QP_CAP |
 454                     IB_QP_DEST_QPN,
 455                     &init_attr);
 456
 457         lnk->wr_tx_cnt = min_t(size_t, SMC_WR_BUF_CNT,
 458                                lnk->qp_attr.cap.max_send_wr);
 459         lnk->wr_rx_cnt = min_t(size_t, SMC_WR_BUF_CNT * 3,
 460                                lnk->qp_attr.cap.max_recv_wr);
 461 }
 462
 463 static void smc_wr_init_sge(struct smc_link *lnk)
 464 {
 465         u32 i;
 466
 467         for (i = 0; i < lnk->wr_tx_cnt; i++) {
 468                 lnk->wr_tx_sges[i].addr =
 469                         lnk->wr_tx_dma_addr + i * SMC_WR_BUF_SIZE;
 470                 lnk->wr_tx_sges[i].length = SMC_WR_TX_SIZE;
 471                 lnk->wr_tx_sges[i].lkey = lnk->roce_pd->local_dma_lkey;
 472                 lnk->wr_tx_rdma_sges[i].tx_rdma_sge[0].wr_tx_rdma_sge[0].lkey =
 473                         lnk->roce_pd->local_dma_lkey;
 474                 lnk->wr_tx_rdma_sges[i].tx_rdma_sge[0].wr_tx_rdma_sge[1].lkey =
 475                         lnk->roce_pd->local_dma_lkey;
 476                 lnk->wr_tx_rdma_sges[i].tx_rdma_sge[1].wr_tx_rdma_sge[0].lkey =
 477                         lnk->roce_pd->local_dma_lkey;
 478                 lnk->wr_tx_rdma_sges[i].tx_rdma_sge[1].wr_tx_rdma_sge[1].lkey =
 479                         lnk->roce_pd->local_dma_lkey;
 480                 lnk->wr_tx_ibs[i].next = NULL;
 481                 lnk->wr_tx_ibs[i].sg_list = &lnk->wr_tx_sges[i];
 482                 lnk->wr_tx_ibs[i].num_sge = 1;
 483                 lnk->wr_tx_ibs[i].opcode = IB_WR_SEND;
 484                 lnk->wr_tx_ibs[i].send_flags =
 485                         IB_SEND_SIGNALED | IB_SEND_SOLICITED;
 486                 lnk->wr_tx_rdmas[i].wr_tx_rdma[0].wr.opcode = IB_WR_RDMA_WRITE;
 487                 lnk->wr_tx_rdmas[i].wr_tx_rdma[1].wr.opcode = IB_WR_RDMA_WRITE;
 488                 lnk->wr_tx_rdmas[i].wr_tx_rdma[0].wr.sg_list =
 489                         lnk->wr_tx_rdma_sges[i].tx_rdma_sge[0].wr_tx_rdma_sge;
 490                 lnk->wr_tx_rdmas[i].wr_tx_rdma[1].wr.sg_list =
 491                         lnk->wr_tx_rdma_sges[i].tx_rdma_sge[1].wr_tx_rdma_sge;
 492         }
 493         for (i = 0; i < lnk->wr_rx_cnt; i++) {
 494                 lnk->wr_rx_sges[i].addr =
 495                         lnk->wr_rx_dma_addr + i * SMC_WR_BUF_SIZE;
 496                 lnk->wr_rx_sges[i].length = SMC_WR_BUF_SIZE;
 497                 lnk->wr_rx_sges[i].lkey = lnk->roce_pd->local_dma_lkey;
 498                 lnk->wr_rx_ibs[i].next = NULL;
 499                 lnk->wr_rx_ibs[i].sg_list = &lnk->wr_rx_sges[i];
 500                 lnk->wr_rx_ibs[i].num_sge = 1;
 501         }
 502         lnk->wr_reg.wr.next = NULL;
 503         lnk->wr_reg.wr.num_sge = 0;
 504         lnk->wr_reg.wr.send_flags = IB_SEND_SIGNALED;
 505         lnk->wr_reg.wr.opcode = IB_WR_REG_MR;
 506         lnk->wr_reg.access = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE;
 507 }
 508
 509 void smc_wr_free_link(struct smc_link *lnk)
 510 {
 511         struct ib_device *ibdev;
 512
 513         memset(lnk->wr_tx_mask, 0,
 514                BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask));
 515
 516         if (!lnk->smcibdev)
 517                 return;
 518         ibdev = lnk->smcibdev->ibdev;
 519
 520         if (lnk->wr_rx_dma_addr) {
 521                 ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
 522                                     SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
 523                                     DMA_FROM_DEVICE);
 524                 lnk->wr_rx_dma_addr = 0;
 525         }
 526         if (lnk->wr_tx_dma_addr) {
 527                 ib_dma_unmap_single(ibdev, lnk->wr_tx_dma_addr,
 528                                     SMC_WR_BUF_SIZE * lnk->wr_tx_cnt,
 529                                     DMA_TO_DEVICE);
 530                 lnk->wr_tx_dma_addr = 0;
 531         }
 532 }
 533
 534 void smc_wr_free_link_mem(struct smc_link *lnk)
 535 {
 536         kfree(lnk->wr_tx_pends);
 537         lnk->wr_tx_pends = NULL;
 538         kfree(lnk->wr_tx_mask);
 539         lnk->wr_tx_mask = NULL;
 540         kfree(lnk->wr_tx_sges);
 541         lnk->wr_tx_sges = NULL;
 542         kfree(lnk->wr_tx_rdma_sges);
 543         lnk->wr_tx_rdma_sges = NULL;
 544         kfree(lnk->wr_rx_sges);
 545         lnk->wr_rx_sges = NULL;
 546         kfree(lnk->wr_tx_rdmas);
 547         lnk->wr_tx_rdmas = NULL;
 548         kfree(lnk->wr_rx_ibs);
 549         lnk->wr_rx_ibs = NULL;
 550         kfree(lnk->wr_tx_ibs);
 551         lnk->wr_tx_ibs = NULL;
 552         kfree(lnk->wr_tx_bufs);
 553         lnk->wr_tx_bufs = NULL;
 554         kfree(lnk->wr_rx_bufs);
 555         lnk->wr_rx_bufs = NULL;
 556 }
 557
 558 int smc_wr_alloc_link_mem(struct smc_link *link)
 559 {
 560         /* allocate link related memory */
 561         link->wr_tx_bufs = kcalloc(SMC_WR_BUF_CNT, SMC_WR_BUF_SIZE, GFP_KERNEL);
 562         if (!link->wr_tx_bufs)
 563                 goto no_mem;
 564         link->wr_rx_bufs = kcalloc(SMC_WR_BUF_CNT * 3, SMC_WR_BUF_SIZE,
 565                                    GFP_KERNEL);
 566         if (!link->wr_rx_bufs)
 567                 goto no_mem_wr_tx_bufs;
 568         link->wr_tx_ibs = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_ibs[0]),
 569                                   GFP_KERNEL);
 570         if (!link->wr_tx_ibs)
 571                 goto no_mem_wr_rx_bufs;
 572         link->wr_rx_ibs = kcalloc(SMC_WR_BUF_CNT * 3,
 573                                   sizeof(link->wr_rx_ibs[0]),
 574                                   GFP_KERNEL);
 575         if (!link->wr_rx_ibs)
 576                 goto no_mem_wr_tx_ibs;
 577         link->wr_tx_rdmas = kcalloc(SMC_WR_BUF_CNT,
 578                                     sizeof(link->wr_tx_rdmas[0]),
 579                                     GFP_KERNEL);
 580         if (!link->wr_tx_rdmas)
 581                 goto no_mem_wr_rx_ibs;
 582         link->wr_tx_rdma_sges = kcalloc(SMC_WR_BUF_CNT,
 583                                         sizeof(link->wr_tx_rdma_sges[0]),
 584                                         GFP_KERNEL);
 585         if (!link->wr_tx_rdma_sges)
 586                 goto no_mem_wr_tx_rdmas;
 587         link->wr_tx_sges = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_sges[0]),
 588                                    GFP_KERNEL);
 589         if (!link->wr_tx_sges)
 590                 goto no_mem_wr_tx_rdma_sges;
 591         link->wr_rx_sges = kcalloc(SMC_WR_BUF_CNT * 3,
 592                                    sizeof(link->wr_rx_sges[0]),
 593                                    GFP_KERNEL);
 594         if (!link->wr_rx_sges)
 595                 goto no_mem_wr_tx_sges;
 596         link->wr_tx_mask = kcalloc(BITS_TO_LONGS(SMC_WR_BUF_CNT),
 597                                    sizeof(*link->wr_tx_mask),
 598                                    GFP_KERNEL);
 599         if (!link->wr_tx_mask)
 600                 goto no_mem_wr_rx_sges;
 601         link->wr_tx_pends = kcalloc(SMC_WR_BUF_CNT,
 602                                     sizeof(link->wr_tx_pends[0]),
 603                                     GFP_KERNEL);
 604         if (!link->wr_tx_pends)
 605                 goto no_mem_wr_tx_mask;
 606         return 0;
 607
 608 no_mem_wr_tx_mask:
 609         kfree(link->wr_tx_mask);
 610 no_mem_wr_rx_sges:
 611         kfree(link->wr_rx_sges);
 612 no_mem_wr_tx_sges:
 613         kfree(link->wr_tx_sges);
 614 no_mem_wr_tx_rdma_sges:
 615         kfree(link->wr_tx_rdma_sges);
 616 no_mem_wr_tx_rdmas:
 617         kfree(link->wr_tx_rdmas);
 618 no_mem_wr_rx_ibs:
 619         kfree(link->wr_rx_ibs);
 620 no_mem_wr_tx_ibs:
 621         kfree(link->wr_tx_ibs);
 622 no_mem_wr_rx_bufs:
 623         kfree(link->wr_rx_bufs);
 624 no_mem_wr_tx_bufs:
 625         kfree(link->wr_tx_bufs);
 626 no_mem:
 627         return -ENOMEM;
 628 }
 629
 630 void smc_wr_remove_dev(struct smc_ib_device *smcibdev)
 631 {
 632         tasklet_kill(&smcibdev->recv_tasklet);
 633         tasklet_kill(&smcibdev->send_tasklet);
 634 }
 635
 636 void smc_wr_add_dev(struct smc_ib_device *smcibdev)
 637 {
 638         tasklet_init(&smcibdev->recv_tasklet, smc_wr_rx_tasklet_fn,
 639                      (unsigned long)smcibdev);
 640         tasklet_init(&smcibdev->send_tasklet, smc_wr_tx_tasklet_fn,
 641                      (unsigned long)smcibdev);
 642 }
 643
 644 int smc_wr_create_link(struct smc_link *lnk)
 645 {
 646         struct ib_device *ibdev = lnk->smcibdev->ibdev;
 647         int rc = 0;
 648
 649         smc_wr_tx_set_wr_id(&lnk->wr_tx_id, 0);
 650         lnk->wr_rx_id = 0;
 651         lnk->wr_rx_dma_addr = ib_dma_map_single(
 652                 ibdev, lnk->wr_rx_bufs, SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
 653                 DMA_FROM_DEVICE);
 654         if (ib_dma_mapping_error(ibdev, lnk->wr_rx_dma_addr)) {
 655                 lnk->wr_rx_dma_addr = 0;
 656                 rc = -EIO;
 657                 goto out;
 658         }
 659         lnk->wr_tx_dma_addr = ib_dma_map_single(
 660                 ibdev, lnk->wr_tx_bufs, SMC_WR_BUF_SIZE * lnk->wr_tx_cnt,
 661                 DMA_TO_DEVICE);
 662         if (ib_dma_mapping_error(ibdev, lnk->wr_tx_dma_addr)) {
 663                 rc = -EIO;
 664                 goto dma_unmap;
 665         }
 666         smc_wr_init_sge(lnk);
 667         memset(lnk->wr_tx_mask, 0,
 668                BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask));
 669         init_waitqueue_head(&lnk->wr_tx_wait);
 670         init_waitqueue_head(&lnk->wr_reg_wait);
 671         return rc;
 672
 673 dma_unmap:
 674         ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
 675                             SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
 676                             DMA_FROM_DEVICE);
 677         lnk->wr_rx_dma_addr = 0;
 678 out:
 679         return rc;
 680 }