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 <maier@linux.vnet.ibm.com>
  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                 struct smc_link_group *lgr;
  96
  97                 for_each_set_bit(i, link->wr_tx_mask, link->wr_tx_cnt) {
  98                         /* clear full struct smc_wr_tx_pend including .priv */
  99                         memset(&link->wr_tx_pends[i], 0,
 100                                sizeof(link->wr_tx_pends[i]));
 101                         memset(&link->wr_tx_bufs[i], 0,
 102                                sizeof(link->wr_tx_bufs[i]));
 103                         clear_bit(i, link->wr_tx_mask);
 104                 }
 105                 /* terminate connections of this link group abnormally */
 106                 lgr = container_of(link, struct smc_link_group,
 107                                    lnk[SMC_SINGLE_LINK]);
 108                 smc_lgr_terminate(lgr);
 109         }
 110         if (pnd_snd.handler)
 111                 pnd_snd.handler(&pnd_snd.priv, link, wc->status);
 112         wake_up(&link->wr_tx_wait);
 113 }
 114
 115 static void smc_wr_tx_tasklet_fn(unsigned long data)
 116 {
 117         struct smc_ib_device *dev = (struct smc_ib_device *)data;
 118         struct ib_wc wc[SMC_WR_MAX_POLL_CQE];
 119         int i = 0, rc;
 120         int polled = 0;
 121
 122 again:
 123         polled++;
 124         do {
 125                 rc = ib_poll_cq(dev->roce_cq_send, SMC_WR_MAX_POLL_CQE, wc);
 126                 if (polled == 1) {
 127                         ib_req_notify_cq(dev->roce_cq_send,
 128                                          IB_CQ_NEXT_COMP |
 129                                          IB_CQ_REPORT_MISSED_EVENTS);
 130                 }
 131                 if (!rc)
 132                         break;
 133                 for (i = 0; i < rc; i++)
 134                         smc_wr_tx_process_cqe(&wc[i]);
 135         } while (rc > 0);
 136         if (polled == 1)
 137                 goto again;
 138 }
 139
 140 void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context)
 141 {
 142         struct smc_ib_device *dev = (struct smc_ib_device *)cq_context;
 143
 144         tasklet_schedule(&dev->send_tasklet);
 145 }
 146
 147 /*---------------------------- request submission ---------------------------*/
 148
 149 static inline int smc_wr_tx_get_free_slot_index(struct smc_link *link, u32 *idx)
 150 {
 151         *idx = link->wr_tx_cnt;
 152         for_each_clear_bit(*idx, link->wr_tx_mask, link->wr_tx_cnt) {
 153                 if (!test_and_set_bit(*idx, link->wr_tx_mask))
 154                         return 0;
 155         }
 156         *idx = link->wr_tx_cnt;
 157         return -EBUSY;
 158 }
 159
 160 /**
 161  * smc_wr_tx_get_free_slot() - returns buffer for message assembly,
 162  *                      and sets info for pending transmit tracking
 163  * @link:               Pointer to smc_link used to later send the message.
 164  * @handler:            Send completion handler function pointer.
 165  * @wr_buf:             Out value returns pointer to message buffer.
 166  * @wr_pend_priv:       Out value returns pointer serving as handler context.
 167  *
 168  * Return: 0 on success, or -errno on error.
 169  */
 170 int smc_wr_tx_get_free_slot(struct smc_link *link,
 171                             smc_wr_tx_handler handler,
 172                             struct smc_wr_buf **wr_buf,
 173                             struct smc_wr_tx_pend_priv **wr_pend_priv)
 174 {
 175         struct smc_wr_tx_pend *wr_pend;
 176         struct ib_send_wr *wr_ib;
 177         u64 wr_id;
 178         u32 idx;
 179         int rc;
 180
 181         *wr_buf = NULL;
 182         *wr_pend_priv = NULL;
 183         if (in_softirq()) {
 184                 rc = smc_wr_tx_get_free_slot_index(link, &idx);
 185                 if (rc)
 186                         return rc;
 187         } else {
 188                 rc = wait_event_interruptible_timeout(
 189                         link->wr_tx_wait,
 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                         struct smc_link_group *lgr;
 195
 196                         lgr = container_of(link, struct smc_link_group,
 197                                            lnk[SMC_SINGLE_LINK]);
 198                         smc_lgr_terminate(lgr);
 199                         return -EPIPE;
 200                 }
 201                 if (rc == -ERESTARTSYS)
 202                         return -EINTR;
 203                 if (idx == link->wr_tx_cnt)
 204                         return -EPIPE;
 205         }
 206         wr_id = smc_wr_tx_get_next_wr_id(link);
 207         wr_pend = &link->wr_tx_pends[idx];
 208         wr_pend->wr_id = wr_id;
 209         wr_pend->handler = handler;
 210         wr_pend->link = link;
 211         wr_pend->idx = idx;
 212         wr_ib = &link->wr_tx_ibs[idx];
 213         wr_ib->wr_id = wr_id;
 214         *wr_buf = &link->wr_tx_bufs[idx];
 215         *wr_pend_priv = &wr_pend->priv;
 216         return 0;
 217 }
 218
 219 int smc_wr_tx_put_slot(struct smc_link *link,
 220                        struct smc_wr_tx_pend_priv *wr_pend_priv)
 221 {
 222         struct smc_wr_tx_pend *pend;
 223
 224         pend = container_of(wr_pend_priv, struct smc_wr_tx_pend, priv);
 225         if (pend->idx < link->wr_tx_cnt) {
 226                 u32 idx = pend->idx;
 227
 228                 /* clear the full struct smc_wr_tx_pend including .priv */
 229                 memset(&link->wr_tx_pends[pend->idx], 0,
 230                        sizeof(link->wr_tx_pends[pend->idx]));
 231                 memset(&link->wr_tx_bufs[pend->idx], 0,
 232                        sizeof(link->wr_tx_bufs[pend->idx]));
 233                 test_and_clear_bit(idx, link->wr_tx_mask);
 234                 return 1;
 235         }
 236
 237         return 0;
 238 }
 239
 240 /* Send prepared WR slot via ib_post_send.
 241  * @priv: pointer to smc_wr_tx_pend_priv identifying prepared message buffer
 242  */
 243 int smc_wr_tx_send(struct smc_link *link, struct smc_wr_tx_pend_priv *priv)
 244 {
 245         struct ib_send_wr *failed_wr = NULL;
 246         struct smc_wr_tx_pend *pend;
 247         int rc;
 248
 249         ib_req_notify_cq(link->smcibdev->roce_cq_send,
 250                          IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
 251         pend = container_of(priv, struct smc_wr_tx_pend, priv);
 252         rc = ib_post_send(link->roce_qp, &link->wr_tx_ibs[pend->idx],
 253                           &failed_wr);
 254         if (rc)
 255                 smc_wr_tx_put_slot(link, priv);
 256         return rc;
 257 }
 258
 259 /* Register a memory region and wait for result. */
 260 int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr)
 261 {
 262         struct ib_send_wr *failed_wr = NULL;
 263         int rc;
 264
 265         ib_req_notify_cq(link->smcibdev->roce_cq_send,
 266                          IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
 267         link->wr_reg_state = POSTED;
 268         link->wr_reg.wr.wr_id = (u64)(uintptr_t)mr;
 269         link->wr_reg.mr = mr;
 270         link->wr_reg.key = mr->rkey;
 271         failed_wr = &link->wr_reg.wr;
 272         rc = ib_post_send(link->roce_qp, &link->wr_reg.wr, &failed_wr);
 273         WARN_ON(failed_wr != &link->wr_reg.wr);
 274         if (rc)
 275                 return rc;
 276
 277         rc = wait_event_interruptible_timeout(link->wr_reg_wait,
 278                                               (link->wr_reg_state != POSTED),
 279                                               SMC_WR_REG_MR_WAIT_TIME);
 280         if (!rc) {
 281                 /* timeout - terminate connections */
 282                 struct smc_link_group *lgr;
 283
 284                 lgr = container_of(link, struct smc_link_group,
 285                                    lnk[SMC_SINGLE_LINK]);
 286                 smc_lgr_terminate(lgr);
 287                 return -EPIPE;
 288         }
 289         if (rc == -ERESTARTSYS)
 290                 return -EINTR;
 291         switch (link->wr_reg_state) {
 292         case CONFIRMED:
 293                 rc = 0;
 294                 break;
 295         case FAILED:
 296                 rc = -EIO;
 297                 break;
 298         case POSTED:
 299                 rc = -EPIPE;
 300                 break;
 301         }
 302         return rc;
 303 }
 304
 305 void smc_wr_tx_dismiss_slots(struct smc_link *link, u8 wr_rx_hdr_type,
 306                              smc_wr_tx_filter filter,
 307                              smc_wr_tx_dismisser dismisser,
 308                              unsigned long data)
 309 {
 310         struct smc_wr_tx_pend_priv *tx_pend;
 311         struct smc_wr_rx_hdr *wr_rx;
 312         int i;
 313
 314         for_each_set_bit(i, link->wr_tx_mask, link->wr_tx_cnt) {
 315                 wr_rx = (struct smc_wr_rx_hdr *)&link->wr_rx_bufs[i];
 316                 if (wr_rx->type != wr_rx_hdr_type)
 317                         continue;
 318                 tx_pend = &link->wr_tx_pends[i].priv;
 319                 if (filter(tx_pend, data))
 320                         dismisser(tx_pend);
 321         }
 322 }
 323
 324 bool smc_wr_tx_has_pending(struct smc_link *link, u8 wr_rx_hdr_type,
 325                            smc_wr_tx_filter filter, unsigned long data)
 326 {
 327         struct smc_wr_tx_pend_priv *tx_pend;
 328         struct smc_wr_rx_hdr *wr_rx;
 329         int i;
 330
 331         for_each_set_bit(i, link->wr_tx_mask, link->wr_tx_cnt) {
 332                 wr_rx = (struct smc_wr_rx_hdr *)&link->wr_rx_bufs[i];
 333                 if (wr_rx->type != wr_rx_hdr_type)
 334                         continue;
 335                 tx_pend = &link->wr_tx_pends[i].priv;
 336                 if (filter(tx_pend, data))
 337                         return true;
 338         }
 339         return false;
 340 }
 341
 342 /****************************** receive queue ********************************/
 343
 344 int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler)
 345 {
 346         struct smc_wr_rx_handler *h_iter;
 347         int rc = 0;
 348
 349         spin_lock(&smc_wr_rx_hash_lock);
 350         hash_for_each_possible(smc_wr_rx_hash, h_iter, list, handler->type) {
 351                 if (h_iter->type == handler->type) {
 352                         rc = -EEXIST;
 353                         goto out_unlock;
 354                 }
 355         }
 356         hash_add(smc_wr_rx_hash, &handler->list, handler->type);
 357 out_unlock:
 358         spin_unlock(&smc_wr_rx_hash_lock);
 359         return rc;
 360 }
 361
 362 /* Demultiplex a received work request based on the message type to its handler.
 363  * Relies on smc_wr_rx_hash having been completely filled before any IB WRs,
 364  * and not being modified any more afterwards so we don't need to lock it.
 365  */
 366 static inline void smc_wr_rx_demultiplex(struct ib_wc *wc)
 367 {
 368         struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
 369         struct smc_wr_rx_handler *handler;
 370         struct smc_wr_rx_hdr *wr_rx;
 371         u64 temp_wr_id;
 372         u32 index;
 373
 374         if (wc->byte_len < sizeof(*wr_rx))
 375                 return; /* short message */
 376         temp_wr_id = wc->wr_id;
 377         index = do_div(temp_wr_id, link->wr_rx_cnt);
 378         wr_rx = (struct smc_wr_rx_hdr *)&link->wr_rx_bufs[index];
 379         hash_for_each_possible(smc_wr_rx_hash, handler, list, wr_rx->type) {
 380                 if (handler->type == wr_rx->type)
 381                         handler->handler(wc, wr_rx);
 382         }
 383 }
 384
 385 static inline void smc_wr_rx_process_cqes(struct ib_wc wc[], int num)
 386 {
 387         struct smc_link *link;
 388         int i;
 389
 390         for (i = 0; i < num; i++) {
 391                 link = wc[i].qp->qp_context;
 392                 if (wc[i].status == IB_WC_SUCCESS) {
 393                         smc_wr_rx_demultiplex(&wc[i]);
 394                         smc_wr_rx_post(link); /* refill WR RX */
 395                 } else {
 396                         struct smc_link_group *lgr;
 397
 398                         /* handle status errors */
 399                         switch (wc[i].status) {
 400                         case IB_WC_RETRY_EXC_ERR:
 401                         case IB_WC_RNR_RETRY_EXC_ERR:
 402                         case IB_WC_WR_FLUSH_ERR:
 403                                 /* terminate connections of this link group
 404                                  * abnormally
 405                                  */
 406                                 lgr = container_of(link, struct smc_link_group,
 407                                                    lnk[SMC_SINGLE_LINK]);
 408                                 smc_lgr_terminate(lgr);
 409                                 break;
 410                         default:
 411                                 smc_wr_rx_post(link); /* refill WR RX */
 412                                 break;
 413                         }
 414                 }
 415         }
 416 }
 417
 418 static void smc_wr_rx_tasklet_fn(unsigned long data)
 419 {
 420         struct smc_ib_device *dev = (struct smc_ib_device *)data;
 421         struct ib_wc wc[SMC_WR_MAX_POLL_CQE];
 422         int polled = 0;
 423         int rc;
 424
 425 again:
 426         polled++;
 427         do {
 428                 memset(&wc, 0, sizeof(wc));
 429                 rc = ib_poll_cq(dev->roce_cq_recv, SMC_WR_MAX_POLL_CQE, wc);
 430                 if (polled == 1) {
 431                         ib_req_notify_cq(dev->roce_cq_recv,
 432                                          IB_CQ_SOLICITED_MASK
 433                                          | IB_CQ_REPORT_MISSED_EVENTS);
 434                 }
 435                 if (!rc)
 436                         break;
 437                 smc_wr_rx_process_cqes(&wc[0], rc);
 438         } while (rc > 0);
 439         if (polled == 1)
 440                 goto again;
 441 }
 442
 443 void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context)
 444 {
 445         struct smc_ib_device *dev = (struct smc_ib_device *)cq_context;
 446
 447         tasklet_schedule(&dev->recv_tasklet);
 448 }
 449
 450 int smc_wr_rx_post_init(struct smc_link *link)
 451 {
 452         u32 i;
 453         int rc = 0;
 454
 455         for (i = 0; i < link->wr_rx_cnt; i++)
 456                 rc = smc_wr_rx_post(link);
 457         return rc;
 458 }
 459
 460 /***************************** init, exit, misc ******************************/
 461
 462 void smc_wr_remember_qp_attr(struct smc_link *lnk)
 463 {
 464         struct ib_qp_attr *attr = &lnk->qp_attr;
 465         struct ib_qp_init_attr init_attr;
 466
 467         memset(attr, 0, sizeof(*attr));
 468         memset(&init_attr, 0, sizeof(init_attr));
 469         ib_query_qp(lnk->roce_qp, attr,
 470                     IB_QP_STATE |
 471                     IB_QP_CUR_STATE |
 472                     IB_QP_PKEY_INDEX |
 473                     IB_QP_PORT |
 474                     IB_QP_QKEY |
 475                     IB_QP_AV |
 476                     IB_QP_PATH_MTU |
 477                     IB_QP_TIMEOUT |
 478                     IB_QP_RETRY_CNT |
 479                     IB_QP_RNR_RETRY |
 480                     IB_QP_RQ_PSN |
 481                     IB_QP_ALT_PATH |
 482                     IB_QP_MIN_RNR_TIMER |
 483                     IB_QP_SQ_PSN |
 484                     IB_QP_PATH_MIG_STATE |
 485                     IB_QP_CAP |
 486                     IB_QP_DEST_QPN,
 487                     &init_attr);
 488
 489         lnk->wr_tx_cnt = min_t(size_t, SMC_WR_BUF_CNT,
 490                                lnk->qp_attr.cap.max_send_wr);
 491         lnk->wr_rx_cnt = min_t(size_t, SMC_WR_BUF_CNT * 3,
 492                                lnk->qp_attr.cap.max_recv_wr);
 493 }
 494
 495 static void smc_wr_init_sge(struct smc_link *lnk)
 496 {
 497         u32 i;
 498
 499         for (i = 0; i < lnk->wr_tx_cnt; i++) {
 500                 lnk->wr_tx_sges[i].addr =
 501                         lnk->wr_tx_dma_addr + i * SMC_WR_BUF_SIZE;
 502                 lnk->wr_tx_sges[i].length = SMC_WR_TX_SIZE;
 503                 lnk->wr_tx_sges[i].lkey = lnk->roce_pd->local_dma_lkey;
 504                 lnk->wr_tx_ibs[i].next = NULL;
 505                 lnk->wr_tx_ibs[i].sg_list = &lnk->wr_tx_sges[i];
 506                 lnk->wr_tx_ibs[i].num_sge = 1;
 507                 lnk->wr_tx_ibs[i].opcode = IB_WR_SEND;
 508                 lnk->wr_tx_ibs[i].send_flags =
 509                         IB_SEND_SIGNALED | IB_SEND_SOLICITED;
 510         }
 511         for (i = 0; i < lnk->wr_rx_cnt; i++) {
 512                 lnk->wr_rx_sges[i].addr =
 513                         lnk->wr_rx_dma_addr + i * SMC_WR_BUF_SIZE;
 514                 lnk->wr_rx_sges[i].length = SMC_WR_BUF_SIZE;
 515                 lnk->wr_rx_sges[i].lkey = lnk->roce_pd->local_dma_lkey;
 516                 lnk->wr_rx_ibs[i].next = NULL;
 517                 lnk->wr_rx_ibs[i].sg_list = &lnk->wr_rx_sges[i];
 518                 lnk->wr_rx_ibs[i].num_sge = 1;
 519         }
 520         lnk->wr_reg.wr.next = NULL;
 521         lnk->wr_reg.wr.num_sge = 0;
 522         lnk->wr_reg.wr.send_flags = IB_SEND_SIGNALED;
 523         lnk->wr_reg.wr.opcode = IB_WR_REG_MR;
 524         lnk->wr_reg.access = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE;
 525 }
 526
 527 void smc_wr_free_link(struct smc_link *lnk)
 528 {
 529         struct ib_device *ibdev;
 530
 531         memset(lnk->wr_tx_mask, 0,
 532                BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask));
 533
 534         if (!lnk->smcibdev)
 535                 return;
 536         ibdev = lnk->smcibdev->ibdev;
 537
 538         if (lnk->wr_rx_dma_addr) {
 539                 ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
 540                                     SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
 541                                     DMA_FROM_DEVICE);
 542                 lnk->wr_rx_dma_addr = 0;
 543         }
 544         if (lnk->wr_tx_dma_addr) {
 545                 ib_dma_unmap_single(ibdev, lnk->wr_tx_dma_addr,
 546                                     SMC_WR_BUF_SIZE * lnk->wr_tx_cnt,
 547                                     DMA_TO_DEVICE);
 548                 lnk->wr_tx_dma_addr = 0;
 549         }
 550 }
 551
 552 void smc_wr_free_link_mem(struct smc_link *lnk)
 553 {
 554         kfree(lnk->wr_tx_pends);
 555         lnk->wr_tx_pends = NULL;
 556         kfree(lnk->wr_tx_mask);
 557         lnk->wr_tx_mask = NULL;
 558         kfree(lnk->wr_tx_sges);
 559         lnk->wr_tx_sges = NULL;
 560         kfree(lnk->wr_rx_sges);
 561         lnk->wr_rx_sges = NULL;
 562         kfree(lnk->wr_rx_ibs);
 563         lnk->wr_rx_ibs = NULL;
 564         kfree(lnk->wr_tx_ibs);
 565         lnk->wr_tx_ibs = NULL;
 566         kfree(lnk->wr_tx_bufs);
 567         lnk->wr_tx_bufs = NULL;
 568         kfree(lnk->wr_rx_bufs);
 569         lnk->wr_rx_bufs = NULL;
 570 }
 571
 572 int smc_wr_alloc_link_mem(struct smc_link *link)
 573 {
 574         /* allocate link related memory */
 575         link->wr_tx_bufs = kcalloc(SMC_WR_BUF_CNT, SMC_WR_BUF_SIZE, GFP_KERNEL);
 576         if (!link->wr_tx_bufs)
 577                 goto no_mem;
 578         link->wr_rx_bufs = kcalloc(SMC_WR_BUF_CNT * 3, SMC_WR_BUF_SIZE,
 579                                    GFP_KERNEL);
 580         if (!link->wr_rx_bufs)
 581                 goto no_mem_wr_tx_bufs;
 582         link->wr_tx_ibs = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_ibs[0]),
 583                                   GFP_KERNEL);
 584         if (!link->wr_tx_ibs)
 585                 goto no_mem_wr_rx_bufs;
 586         link->wr_rx_ibs = kcalloc(SMC_WR_BUF_CNT * 3,
 587                                   sizeof(link->wr_rx_ibs[0]),
 588                                   GFP_KERNEL);
 589         if (!link->wr_rx_ibs)
 590                 goto no_mem_wr_tx_ibs;
 591         link->wr_tx_sges = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_sges[0]),
 592                                    GFP_KERNEL);
 593         if (!link->wr_tx_sges)
 594                 goto no_mem_wr_rx_ibs;
 595         link->wr_rx_sges = kcalloc(SMC_WR_BUF_CNT * 3,
 596                                    sizeof(link->wr_rx_sges[0]),
 597                                    GFP_KERNEL);
 598         if (!link->wr_rx_sges)
 599                 goto no_mem_wr_tx_sges;
 600         link->wr_tx_mask = kzalloc(
 601                 BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*link->wr_tx_mask),
 602                 GFP_KERNEL);
 603         if (!link->wr_tx_mask)
 604                 goto no_mem_wr_rx_sges;
 605         link->wr_tx_pends = kcalloc(SMC_WR_BUF_CNT,
 606                                     sizeof(link->wr_tx_pends[0]),
 607                                     GFP_KERNEL);
 608         if (!link->wr_tx_pends)
 609                 goto no_mem_wr_tx_mask;
 610         return 0;
 611
 612 no_mem_wr_tx_mask:
 613         kfree(link->wr_tx_mask);
 614 no_mem_wr_rx_sges:
 615         kfree(link->wr_rx_sges);
 616 no_mem_wr_tx_sges:
 617         kfree(link->wr_tx_sges);
 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 }