drivers/infiniband/sw/rxe/rxe_req.c

   1 /*
   2  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
   3  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/skbuff.h>
  35 #include <crypto/hash.h>
  36
  37 #include "rxe.h"
  38 #include "rxe_loc.h"
  39 #include "rxe_queue.h"
  40
  41 static int next_opcode(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
  42                        u32 opcode);
  43
  44 static inline void retry_first_write_send(struct rxe_qp *qp,
  45                                           struct rxe_send_wqe *wqe,
  46                                           unsigned int mask, int npsn)
  47 {
  48         int i;
  49
  50         for (i = 0; i < npsn; i++) {
  51                 int to_send = (wqe->dma.resid > qp->mtu) ?
  52                                 qp->mtu : wqe->dma.resid;
  53
  54                 qp->req.opcode = next_opcode(qp, wqe,
  55                                              wqe->wr.opcode);
  56
  57                 if (wqe->wr.send_flags & IB_SEND_INLINE) {
  58                         wqe->dma.resid -= to_send;
  59                         wqe->dma.sge_offset += to_send;
  60                 } else {
  61                         advance_dma_data(&wqe->dma, to_send);
  62                 }
  63                 if (mask & WR_WRITE_MASK)
  64                         wqe->iova += qp->mtu;
  65         }
  66 }
  67
  68 static void req_retry(struct rxe_qp *qp)
  69 {
  70         struct rxe_send_wqe *wqe;
  71         unsigned int wqe_index;
  72         unsigned int mask;
  73         int npsn;
  74         int first = 1;
  75
  76         wqe = queue_head(qp->sq.queue);
  77         npsn = (qp->comp.psn - wqe->first_psn) & BTH_PSN_MASK;
  78
  79         qp->req.wqe_index       = consumer_index(qp->sq.queue);
  80         qp->req.psn             = qp->comp.psn;
  81         qp->req.opcode          = -1;
  82
  83         for (wqe_index = consumer_index(qp->sq.queue);
  84                 wqe_index != producer_index(qp->sq.queue);
  85                 wqe_index = next_index(qp->sq.queue, wqe_index)) {
  86                 wqe = addr_from_index(qp->sq.queue, wqe_index);
  87                 mask = wr_opcode_mask(wqe->wr.opcode, qp);
  88
  89                 if (wqe->state == wqe_state_posted)
  90                         break;
  91
  92                 if (wqe->state == wqe_state_done)
  93                         continue;
  94
  95                 wqe->iova = (mask & WR_ATOMIC_MASK) ?
  96                              wqe->wr.wr.atomic.remote_addr :
  97                              (mask & WR_READ_OR_WRITE_MASK) ?
  98                              wqe->wr.wr.rdma.remote_addr :
  99                              0;
 100
 101                 if (!first || (mask & WR_READ_MASK) == 0) {
 102                         wqe->dma.resid = wqe->dma.length;
 103                         wqe->dma.cur_sge = 0;
 104                         wqe->dma.sge_offset = 0;
 105                 }
 106
 107                 if (first) {
 108                         first = 0;
 109
 110                         if (mask & WR_WRITE_OR_SEND_MASK)
 111                                 retry_first_write_send(qp, wqe, mask, npsn);
 112
 113                         if (mask & WR_READ_MASK)
 114                                 wqe->iova += npsn * qp->mtu;
 115                 }
 116
 117                 wqe->state = wqe_state_posted;
 118         }
 119 }
 120
 121 void rnr_nak_timer(struct timer_list *t)
 122 {
 123         struct rxe_qp *qp = from_timer(qp, t, rnr_nak_timer);
 124
 125         pr_debug("qp#%d rnr nak timer fired\n", qp_num(qp));
 126         rxe_run_task(&qp->req.task, 1);
 127 }
 128
 129 static struct rxe_send_wqe *req_next_wqe(struct rxe_qp *qp)
 130 {
 131         struct rxe_send_wqe *wqe = queue_head(qp->sq.queue);
 132         unsigned long flags;
 133
 134         if (unlikely(qp->req.state == QP_STATE_DRAIN)) {
 135                 /* check to see if we are drained;
 136                  * state_lock used by requester and completer
 137                  */
 138                 spin_lock_irqsave(&qp->state_lock, flags);
 139                 do {
 140                         if (qp->req.state != QP_STATE_DRAIN) {
 141                                 /* comp just finished */
 142                                 spin_unlock_irqrestore(&qp->state_lock,
 143                                                        flags);
 144                                 break;
 145                         }
 146
 147                         if (wqe && ((qp->req.wqe_index !=
 148                                 consumer_index(qp->sq.queue)) ||
 149                                 (wqe->state != wqe_state_posted))) {
 150                                 /* comp not done yet */
 151                                 spin_unlock_irqrestore(&qp->state_lock,
 152                                                        flags);
 153                                 break;
 154                         }
 155
 156                         qp->req.state = QP_STATE_DRAINED;
 157                         spin_unlock_irqrestore(&qp->state_lock, flags);
 158
 159                         if (qp->ibqp.event_handler) {
 160                                 struct ib_event ev;
 161
 162                                 ev.device = qp->ibqp.device;
 163                                 ev.element.qp = &qp->ibqp;
 164                                 ev.event = IB_EVENT_SQ_DRAINED;
 165                                 qp->ibqp.event_handler(&ev,
 166                                         qp->ibqp.qp_context);
 167                         }
 168                 } while (0);
 169         }
 170
 171         if (qp->req.wqe_index == producer_index(qp->sq.queue))
 172                 return NULL;
 173
 174         wqe = addr_from_index(qp->sq.queue, qp->req.wqe_index);
 175
 176         if (unlikely((qp->req.state == QP_STATE_DRAIN ||
 177                       qp->req.state == QP_STATE_DRAINED) &&
 178                      (wqe->state != wqe_state_processing)))
 179                 return NULL;
 180
 181         if (unlikely((wqe->wr.send_flags & IB_SEND_FENCE) &&
 182                      (qp->req.wqe_index != consumer_index(qp->sq.queue)))) {
 183                 qp->req.wait_fence = 1;
 184                 return NULL;
 185         }
 186
 187         wqe->mask = wr_opcode_mask(wqe->wr.opcode, qp);
 188         return wqe;
 189 }
 190
 191 static int next_opcode_rc(struct rxe_qp *qp, u32 opcode, int fits)
 192 {
 193         switch (opcode) {
 194         case IB_WR_RDMA_WRITE:
 195                 if (qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_FIRST ||
 196                     qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_MIDDLE)
 197                         return fits ?
 198                                 IB_OPCODE_RC_RDMA_WRITE_LAST :
 199                                 IB_OPCODE_RC_RDMA_WRITE_MIDDLE;
 200                 else
 201                         return fits ?
 202                                 IB_OPCODE_RC_RDMA_WRITE_ONLY :
 203                                 IB_OPCODE_RC_RDMA_WRITE_FIRST;
 204
 205         case IB_WR_RDMA_WRITE_WITH_IMM:
 206                 if (qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_FIRST ||
 207                     qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_MIDDLE)
 208                         return fits ?
 209                                 IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE :
 210                                 IB_OPCODE_RC_RDMA_WRITE_MIDDLE;
 211                 else
 212                         return fits ?
 213                                 IB_OPCODE_RC_RDMA_WRITE_ONLY_WITH_IMMEDIATE :
 214                                 IB_OPCODE_RC_RDMA_WRITE_FIRST;
 215
 216         case IB_WR_SEND:
 217                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 218                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 219                         return fits ?
 220                                 IB_OPCODE_RC_SEND_LAST :
 221                                 IB_OPCODE_RC_SEND_MIDDLE;
 222                 else
 223                         return fits ?
 224                                 IB_OPCODE_RC_SEND_ONLY :
 225                                 IB_OPCODE_RC_SEND_FIRST;
 226
 227         case IB_WR_SEND_WITH_IMM:
 228                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 229                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 230                         return fits ?
 231                                 IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE :
 232                                 IB_OPCODE_RC_SEND_MIDDLE;
 233                 else
 234                         return fits ?
 235                                 IB_OPCODE_RC_SEND_ONLY_WITH_IMMEDIATE :
 236                                 IB_OPCODE_RC_SEND_FIRST;
 237
 238         case IB_WR_RDMA_READ:
 239                 return IB_OPCODE_RC_RDMA_READ_REQUEST;
 240
 241         case IB_WR_ATOMIC_CMP_AND_SWP:
 242                 return IB_OPCODE_RC_COMPARE_SWAP;
 243
 244         case IB_WR_ATOMIC_FETCH_AND_ADD:
 245                 return IB_OPCODE_RC_FETCH_ADD;
 246
 247         case IB_WR_SEND_WITH_INV:
 248                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 249                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 250                         return fits ? IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE :
 251                                 IB_OPCODE_RC_SEND_MIDDLE;
 252                 else
 253                         return fits ? IB_OPCODE_RC_SEND_ONLY_WITH_INVALIDATE :
 254                                 IB_OPCODE_RC_SEND_FIRST;
 255         case IB_WR_REG_MR:
 256         case IB_WR_LOCAL_INV:
 257                 return opcode;
 258         }
 259
 260         return -EINVAL;
 261 }
 262
 263 static int next_opcode_uc(struct rxe_qp *qp, u32 opcode, int fits)
 264 {
 265         switch (opcode) {
 266         case IB_WR_RDMA_WRITE:
 267                 if (qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_FIRST ||
 268                     qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_MIDDLE)
 269                         return fits ?
 270                                 IB_OPCODE_UC_RDMA_WRITE_LAST :
 271                                 IB_OPCODE_UC_RDMA_WRITE_MIDDLE;
 272                 else
 273                         return fits ?
 274                                 IB_OPCODE_UC_RDMA_WRITE_ONLY :
 275                                 IB_OPCODE_UC_RDMA_WRITE_FIRST;
 276
 277         case IB_WR_RDMA_WRITE_WITH_IMM:
 278                 if (qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_FIRST ||
 279                     qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_MIDDLE)
 280                         return fits ?
 281                                 IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE :
 282                                 IB_OPCODE_UC_RDMA_WRITE_MIDDLE;
 283                 else
 284                         return fits ?
 285                                 IB_OPCODE_UC_RDMA_WRITE_ONLY_WITH_IMMEDIATE :
 286                                 IB_OPCODE_UC_RDMA_WRITE_FIRST;
 287
 288         case IB_WR_SEND:
 289                 if (qp->req.opcode == IB_OPCODE_UC_SEND_FIRST ||
 290                     qp->req.opcode == IB_OPCODE_UC_SEND_MIDDLE)
 291                         return fits ?
 292                                 IB_OPCODE_UC_SEND_LAST :
 293                                 IB_OPCODE_UC_SEND_MIDDLE;
 294                 else
 295                         return fits ?
 296                                 IB_OPCODE_UC_SEND_ONLY :
 297                                 IB_OPCODE_UC_SEND_FIRST;
 298
 299         case IB_WR_SEND_WITH_IMM:
 300                 if (qp->req.opcode == IB_OPCODE_UC_SEND_FIRST ||
 301                     qp->req.opcode == IB_OPCODE_UC_SEND_MIDDLE)
 302                         return fits ?
 303                                 IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE :
 304                                 IB_OPCODE_UC_SEND_MIDDLE;
 305                 else
 306                         return fits ?
 307                                 IB_OPCODE_UC_SEND_ONLY_WITH_IMMEDIATE :
 308                                 IB_OPCODE_UC_SEND_FIRST;
 309         }
 310
 311         return -EINVAL;
 312 }
 313
 314 static int next_opcode(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 315                        u32 opcode)
 316 {
 317         int fits = (wqe->dma.resid <= qp->mtu);
 318
 319         switch (qp_type(qp)) {
 320         case IB_QPT_RC:
 321                 return next_opcode_rc(qp, opcode, fits);
 322
 323         case IB_QPT_UC:
 324                 return next_opcode_uc(qp, opcode, fits);
 325
 326         case IB_QPT_SMI:
 327         case IB_QPT_UD:
 328         case IB_QPT_GSI:
 329                 switch (opcode) {
 330                 case IB_WR_SEND:
 331                         return IB_OPCODE_UD_SEND_ONLY;
 332
 333                 case IB_WR_SEND_WITH_IMM:
 334                         return IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE;
 335                 }
 336                 break;
 337
 338         default:
 339                 break;
 340         }
 341
 342         return -EINVAL;
 343 }
 344
 345 static inline int check_init_depth(struct rxe_qp *qp, struct rxe_send_wqe *wqe)
 346 {
 347         int depth;
 348
 349         if (wqe->has_rd_atomic)
 350                 return 0;
 351
 352         qp->req.need_rd_atomic = 1;
 353         depth = atomic_dec_return(&qp->req.rd_atomic);
 354
 355         if (depth >= 0) {
 356                 qp->req.need_rd_atomic = 0;
 357                 wqe->has_rd_atomic = 1;
 358                 return 0;
 359         }
 360
 361         atomic_inc(&qp->req.rd_atomic);
 362         return -EAGAIN;
 363 }
 364
 365 static inline int get_mtu(struct rxe_qp *qp)
 366 {
 367         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 368
 369         if ((qp_type(qp) == IB_QPT_RC) || (qp_type(qp) == IB_QPT_UC))
 370                 return qp->mtu;
 371
 372         return rxe->port.mtu_cap;
 373 }
 374
 375 static struct sk_buff *init_req_packet(struct rxe_qp *qp,
 376                                        struct rxe_send_wqe *wqe,
 377                                        int opcode, int payload,
 378                                        struct rxe_pkt_info *pkt)
 379 {
 380         struct rxe_dev          *rxe = to_rdev(qp->ibqp.device);
 381         struct rxe_port         *port = &rxe->port;
 382         struct sk_buff          *skb;
 383         struct rxe_send_wr      *ibwr = &wqe->wr;
 384         struct rxe_av           *av;
 385         int                     pad = (-payload) & 0x3;
 386         int                     paylen;
 387         int                     solicited;
 388         u16                     pkey;
 389         u32                     qp_num;
 390         int                     ack_req;
 391
 392         /* length from start of bth to end of icrc */
 393         paylen = rxe_opcode[opcode].length + payload + pad + RXE_ICRC_SIZE;
 394
 395         /* pkt->hdr, rxe, port_num and mask are initialized in ifc
 396          * layer
 397          */
 398         pkt->opcode     = opcode;
 399         pkt->qp         = qp;
 400         pkt->psn        = qp->req.psn;
 401         pkt->mask       = rxe_opcode[opcode].mask;
 402         pkt->paylen     = paylen;
 403         pkt->offset     = 0;
 404         pkt->wqe        = wqe;
 405
 406         /* init skb */
 407         av = rxe_get_av(pkt);
 408         skb = rxe_init_packet(rxe, av, paylen, pkt);
 409         if (unlikely(!skb))
 410                 return NULL;
 411
 412         /* init bth */
 413         solicited = (ibwr->send_flags & IB_SEND_SOLICITED) &&
 414                         (pkt->mask & RXE_END_MASK) &&
 415                         ((pkt->mask & (RXE_SEND_MASK)) ||
 416                         (pkt->mask & (RXE_WRITE_MASK | RXE_IMMDT_MASK)) ==
 417                         (RXE_WRITE_MASK | RXE_IMMDT_MASK));
 418
 419         pkey = (qp_type(qp) == IB_QPT_GSI) ?
 420                  port->pkey_tbl[ibwr->wr.ud.pkey_index] :
 421                  port->pkey_tbl[qp->attr.pkey_index];
 422
 423         qp_num = (pkt->mask & RXE_DETH_MASK) ? ibwr->wr.ud.remote_qpn :
 424                                          qp->attr.dest_qp_num;
 425
 426         ack_req = ((pkt->mask & RXE_END_MASK) ||
 427                 (qp->req.noack_pkts++ > RXE_MAX_PKT_PER_ACK));
 428         if (ack_req)
 429                 qp->req.noack_pkts = 0;
 430
 431         bth_init(pkt, pkt->opcode, solicited, 0, pad, pkey, qp_num,
 432                  ack_req, pkt->psn);
 433
 434         /* init optional headers */
 435         if (pkt->mask & RXE_RETH_MASK) {
 436                 reth_set_rkey(pkt, ibwr->wr.rdma.rkey);
 437                 reth_set_va(pkt, wqe->iova);
 438                 reth_set_len(pkt, wqe->dma.length);
 439         }
 440
 441         if (pkt->mask & RXE_IMMDT_MASK)
 442                 immdt_set_imm(pkt, ibwr->ex.imm_data);
 443
 444         if (pkt->mask & RXE_IETH_MASK)
 445                 ieth_set_rkey(pkt, ibwr->ex.invalidate_rkey);
 446
 447         if (pkt->mask & RXE_ATMETH_MASK) {
 448                 atmeth_set_va(pkt, wqe->iova);
 449                 if (opcode == IB_OPCODE_RC_COMPARE_SWAP ||
 450                     opcode == IB_OPCODE_RD_COMPARE_SWAP) {
 451                         atmeth_set_swap_add(pkt, ibwr->wr.atomic.swap);
 452                         atmeth_set_comp(pkt, ibwr->wr.atomic.compare_add);
 453                 } else {
 454                         atmeth_set_swap_add(pkt, ibwr->wr.atomic.compare_add);
 455                 }
 456                 atmeth_set_rkey(pkt, ibwr->wr.atomic.rkey);
 457         }
 458
 459         if (pkt->mask & RXE_DETH_MASK) {
 460                 if (qp->ibqp.qp_num == 1)
 461                         deth_set_qkey(pkt, GSI_QKEY);
 462                 else
 463                         deth_set_qkey(pkt, ibwr->wr.ud.remote_qkey);
 464                 deth_set_sqp(pkt, qp->ibqp.qp_num);
 465         }
 466
 467         return skb;
 468 }
 469
 470 static int fill_packet(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 471                        struct rxe_pkt_info *pkt, struct sk_buff *skb,
 472                        int paylen)
 473 {
 474         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 475         u32 crc = 0;
 476         u32 *p;
 477         int err;
 478
 479         err = rxe_prepare(rxe, pkt, skb, &crc);
 480         if (err)
 481                 return err;
 482
 483         if (pkt->mask & RXE_WRITE_OR_SEND) {
 484                 if (wqe->wr.send_flags & IB_SEND_INLINE) {
 485                         u8 *tmp = &wqe->dma.inline_data[wqe->dma.sge_offset];
 486
 487                         crc = rxe_crc32(rxe, crc, tmp, paylen);
 488                         memcpy(payload_addr(pkt), tmp, paylen);
 489
 490                         wqe->dma.resid -= paylen;
 491                         wqe->dma.sge_offset += paylen;
 492                 } else {
 493                         err = copy_data(rxe, qp->pd, 0, &wqe->dma,
 494                                         payload_addr(pkt), paylen,
 495                                         from_mem_obj,
 496                                         &crc);
 497                         if (err)
 498                                 return err;
 499                 }
 500         }
 501         p = payload_addr(pkt) + paylen + bth_pad(pkt);
 502
 503         *p = ~crc;
 504
 505         return 0;
 506 }
 507
 508 static void update_wqe_state(struct rxe_qp *qp,
 509                 struct rxe_send_wqe *wqe,
 510                 struct rxe_pkt_info *pkt)
 511 {
 512         if (pkt->mask & RXE_END_MASK) {
 513                 if (qp_type(qp) == IB_QPT_RC)
 514                         wqe->state = wqe_state_pending;
 515         } else {
 516                 wqe->state = wqe_state_processing;
 517         }
 518 }
 519
 520 static void update_wqe_psn(struct rxe_qp *qp,
 521                            struct rxe_send_wqe *wqe,
 522                            struct rxe_pkt_info *pkt,
 523                            int payload)
 524 {
 525         /* number of packets left to send including current one */
 526         int num_pkt = (wqe->dma.resid + payload + qp->mtu - 1) / qp->mtu;
 527
 528         /* handle zero length packet case */
 529         if (num_pkt == 0)
 530                 num_pkt = 1;
 531
 532         if (pkt->mask & RXE_START_MASK) {
 533                 wqe->first_psn = qp->req.psn;
 534                 wqe->last_psn = (qp->req.psn + num_pkt - 1) & BTH_PSN_MASK;
 535         }
 536
 537         if (pkt->mask & RXE_READ_MASK)
 538                 qp->req.psn = (wqe->first_psn + num_pkt) & BTH_PSN_MASK;
 539         else
 540                 qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK;
 541 }
 542
 543 static void save_state(struct rxe_send_wqe *wqe,
 544                        struct rxe_qp *qp,
 545                        struct rxe_send_wqe *rollback_wqe,
 546                        u32 *rollback_psn)
 547 {
 548         rollback_wqe->state     = wqe->state;
 549         rollback_wqe->first_psn = wqe->first_psn;
 550         rollback_wqe->last_psn  = wqe->last_psn;
 551         *rollback_psn           = qp->req.psn;
 552 }
 553
 554 static void rollback_state(struct rxe_send_wqe *wqe,
 555                            struct rxe_qp *qp,
 556                            struct rxe_send_wqe *rollback_wqe,
 557                            u32 rollback_psn)
 558 {
 559         wqe->state     = rollback_wqe->state;
 560         wqe->first_psn = rollback_wqe->first_psn;
 561         wqe->last_psn  = rollback_wqe->last_psn;
 562         qp->req.psn    = rollback_psn;
 563 }
 564
 565 static void update_state(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 566                          struct rxe_pkt_info *pkt, int payload)
 567 {
 568         qp->req.opcode = pkt->opcode;
 569
 570         if (pkt->mask & RXE_END_MASK)
 571                 qp->req.wqe_index = next_index(qp->sq.queue, qp->req.wqe_index);
 572
 573         qp->need_req_skb = 0;
 574
 575         if (qp->qp_timeout_jiffies && !timer_pending(&qp->retrans_timer))
 576                 mod_timer(&qp->retrans_timer,
 577                           jiffies + qp->qp_timeout_jiffies);
 578 }
 579
 580 int rxe_requester(void *arg)
 581 {
 582         struct rxe_qp *qp = (struct rxe_qp *)arg;
 583         struct rxe_pkt_info pkt;
 584         struct sk_buff *skb;
 585         struct rxe_send_wqe *wqe;
 586         enum rxe_hdr_mask mask;
 587         int payload;
 588         int mtu;
 589         int opcode;
 590         int ret;
 591         struct rxe_send_wqe rollback_wqe;
 592         u32 rollback_psn;
 593
 594         rxe_add_ref(qp);
 595
 596 next_wqe:
 597         if (unlikely(!qp->valid || qp->req.state == QP_STATE_ERROR))
 598                 goto exit;
 599
 600         if (unlikely(qp->req.state == QP_STATE_RESET)) {
 601                 qp->req.wqe_index = consumer_index(qp->sq.queue);
 602                 qp->req.opcode = -1;
 603                 qp->req.need_rd_atomic = 0;
 604                 qp->req.wait_psn = 0;
 605                 qp->req.need_retry = 0;
 606                 goto exit;
 607         }
 608
 609         if (unlikely(qp->req.need_retry)) {
 610                 req_retry(qp);
 611                 qp->req.need_retry = 0;
 612         }
 613
 614         wqe = req_next_wqe(qp);
 615         if (unlikely(!wqe))
 616                 goto exit;
 617
 618         if (wqe->mask & WR_REG_MASK) {
 619                 if (wqe->wr.opcode == IB_WR_LOCAL_INV) {
 620                         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 621                         struct rxe_mem *rmr;
 622
 623                         rmr = rxe_pool_get_index(&rxe->mr_pool,
 624                                                  wqe->wr.ex.invalidate_rkey >> 8);
 625                         if (!rmr) {
 626                                 pr_err("No mr for key %#x\n",
 627                                        wqe->wr.ex.invalidate_rkey);
 628                                 wqe->state = wqe_state_error;
 629                                 wqe->status = IB_WC_MW_BIND_ERR;
 630                                 goto exit;
 631                         }
 632                         rmr->state = RXE_MEM_STATE_FREE;
 633                         rxe_drop_ref(rmr);
 634                         wqe->state = wqe_state_done;
 635                         wqe->status = IB_WC_SUCCESS;
 636                 } else if (wqe->wr.opcode == IB_WR_REG_MR) {
 637                         struct rxe_mem *rmr = to_rmr(wqe->wr.wr.reg.mr);
 638
 639                         rmr->state = RXE_MEM_STATE_VALID;
 640                         rmr->access = wqe->wr.wr.reg.access;
 641                         rmr->lkey = wqe->wr.wr.reg.key;
 642                         rmr->rkey = wqe->wr.wr.reg.key;
 643                         wqe->state = wqe_state_done;
 644                         wqe->status = IB_WC_SUCCESS;
 645                 } else {
 646                         goto exit;
 647                 }
 648                 qp->req.wqe_index = next_index(qp->sq.queue,
 649                                                 qp->req.wqe_index);
 650                 goto next_wqe;
 651         }
 652
 653         if (unlikely(qp_type(qp) == IB_QPT_RC &&
 654                      qp->req.psn > (qp->comp.psn + RXE_MAX_UNACKED_PSNS))) {
 655                 qp->req.wait_psn = 1;
 656                 goto exit;
 657         }
 658
 659         /* Limit the number of inflight SKBs per QP */
 660         if (unlikely(atomic_read(&qp->skb_out) >
 661                      RXE_INFLIGHT_SKBS_PER_QP_HIGH)) {
 662                 qp->need_req_skb = 1;
 663                 goto exit;
 664         }
 665
 666         opcode = next_opcode(qp, wqe, wqe->wr.opcode);
 667         if (unlikely(opcode < 0)) {
 668                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 669                 goto exit;
 670         }
 671
 672         mask = rxe_opcode[opcode].mask;
 673         if (unlikely(mask & RXE_READ_OR_ATOMIC)) {
 674                 if (check_init_depth(qp, wqe))
 675                         goto exit;
 676         }
 677
 678         mtu = get_mtu(qp);
 679         payload = (mask & RXE_WRITE_OR_SEND) ? wqe->dma.resid : 0;
 680         if (payload > mtu) {
 681                 if (qp_type(qp) == IB_QPT_UD) {
 682                         /* C10-93.1.1: If the total sum of all the buffer lengths specified for a
 683                          * UD message exceeds the MTU of the port as returned by QueryHCA, the CI
 684                          * shall not emit any packets for this message. Further, the CI shall not
 685                          * generate an error due to this condition.
 686                          */
 687
 688                         /* fake a successful UD send */
 689                         wqe->first_psn = qp->req.psn;
 690                         wqe->last_psn = qp->req.psn;
 691                         qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK;
 692                         qp->req.opcode = IB_OPCODE_UD_SEND_ONLY;
 693                         qp->req.wqe_index = next_index(qp->sq.queue,
 694                                                        qp->req.wqe_index);
 695                         wqe->state = wqe_state_done;
 696                         wqe->status = IB_WC_SUCCESS;
 697                         __rxe_do_task(&qp->comp.task);
 698                         rxe_drop_ref(qp);
 699                         return 0;
 700                 }
 701                 payload = mtu;
 702         }
 703
 704         skb = init_req_packet(qp, wqe, opcode, payload, &pkt);
 705         if (unlikely(!skb)) {
 706                 pr_err("qp#%d Failed allocating skb\n", qp_num(qp));
 707                 goto err;
 708         }
 709
 710         if (fill_packet(qp, wqe, &pkt, skb, payload)) {
 711                 pr_debug("qp#%d Error during fill packet\n", qp_num(qp));
 712                 goto err;
 713         }
 714
 715         /*
 716          * To prevent a race on wqe access between requester and completer,
 717          * wqe members state and psn need to be set before calling
 718          * rxe_xmit_packet().
 719          * Otherwise, completer might initiate an unjustified retry flow.
 720          */
 721         save_state(wqe, qp, &rollback_wqe, &rollback_psn);
 722         update_wqe_state(qp, wqe, &pkt);
 723         update_wqe_psn(qp, wqe, &pkt, payload);
 724         ret = rxe_xmit_packet(to_rdev(qp->ibqp.device), qp, &pkt, skb);
 725         if (ret) {
 726                 qp->need_req_skb = 1;
 727
 728                 rollback_state(wqe, qp, &rollback_wqe, rollback_psn);
 729
 730                 if (ret == -EAGAIN) {
 731                         kfree_skb(skb);
 732                         rxe_run_task(&qp->req.task, 1);
 733                         goto exit;
 734                 }
 735
 736                 goto err;
 737         }
 738
 739         update_state(qp, wqe, &pkt, payload);
 740
 741         goto next_wqe;
 742
 743 err:
 744         kfree_skb(skb);
 745         wqe->status = IB_WC_LOC_PROT_ERR;
 746         wqe->state = wqe_state_error;
 747         __rxe_do_task(&qp->comp.task);
 748
 749 exit:
 750         rxe_drop_ref(qp);
 751         return -EAGAIN;
 752 }