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
  36 #include "rxe.h"
  37 #include "rxe_loc.h"
  38 #include "rxe_queue.h"
  39
  40 static int next_opcode(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
  41                        u32 opcode);
  42
  43 static inline void retry_first_write_send(struct rxe_qp *qp,
  44                                           struct rxe_send_wqe *wqe,
  45                                           unsigned mask, int npsn)
  46 {
  47         int i;
  48
  49         for (i = 0; i < npsn; i++) {
  50                 int to_send = (wqe->dma.resid > qp->mtu) ?
  51                                 qp->mtu : wqe->dma.resid;
  52
  53                 qp->req.opcode = next_opcode(qp, wqe,
  54                                              wqe->wr.opcode);
  55
  56                 if (wqe->wr.send_flags & IB_SEND_INLINE) {
  57                         wqe->dma.resid -= to_send;
  58                         wqe->dma.sge_offset += to_send;
  59                 } else {
  60                         advance_dma_data(&wqe->dma, to_send);
  61                 }
  62                 if (mask & WR_WRITE_MASK)
  63                         wqe->iova += qp->mtu;
  64         }
  65 }
  66
  67 static void req_retry(struct rxe_qp *qp)
  68 {
  69         struct rxe_send_wqe *wqe;
  70         unsigned int wqe_index;
  71         unsigned int mask;
  72         int npsn;
  73         int first = 1;
  74
  75         wqe = queue_head(qp->sq.queue);
  76         npsn = (qp->comp.psn - wqe->first_psn) & BTH_PSN_MASK;
  77
  78         qp->req.wqe_index       = consumer_index(qp->sq.queue);
  79         qp->req.psn             = qp->comp.psn;
  80         qp->req.opcode          = -1;
  81
  82         for (wqe_index = consumer_index(qp->sq.queue);
  83                 wqe_index != producer_index(qp->sq.queue);
  84                 wqe_index = next_index(qp->sq.queue, wqe_index)) {
  85                 wqe = addr_from_index(qp->sq.queue, wqe_index);
  86                 mask = wr_opcode_mask(wqe->wr.opcode, qp);
  87
  88                 if (wqe->state == wqe_state_posted)
  89                         break;
  90
  91                 if (wqe->state == wqe_state_done)
  92                         continue;
  93
  94                 wqe->iova = (mask & WR_ATOMIC_MASK) ?
  95                              wqe->wr.wr.atomic.remote_addr :
  96                              (mask & WR_READ_OR_WRITE_MASK) ?
  97                              wqe->wr.wr.rdma.remote_addr :
  98                              0;
  99
 100                 if (!first || (mask & WR_READ_MASK) == 0) {
 101                         wqe->dma.resid = wqe->dma.length;
 102                         wqe->dma.cur_sge = 0;
 103                         wqe->dma.sge_offset = 0;
 104                 }
 105
 106                 if (first) {
 107                         first = 0;
 108
 109                         if (mask & WR_WRITE_OR_SEND_MASK)
 110                                 retry_first_write_send(qp, wqe, mask, npsn);
 111
 112                         if (mask & WR_READ_MASK)
 113                                 wqe->iova += npsn * qp->mtu;
 114                 }
 115
 116                 wqe->state = wqe_state_posted;
 117         }
 118 }
 119
 120 void rnr_nak_timer(unsigned long data)
 121 {
 122         struct rxe_qp *qp = (struct rxe_qp *)data;
 123
 124         pr_debug("qp#%d rnr nak timer fired\n", qp_num(qp));
 125         rxe_run_task(&qp->req.task, 1);
 126 }
 127
 128 static struct rxe_send_wqe *req_next_wqe(struct rxe_qp *qp)
 129 {
 130         struct rxe_send_wqe *wqe = queue_head(qp->sq.queue);
 131         unsigned long flags;
 132
 133         if (unlikely(qp->req.state == QP_STATE_DRAIN)) {
 134                 /* check to see if we are drained;
 135                  * state_lock used by requester and completer
 136                  */
 137                 spin_lock_irqsave(&qp->state_lock, flags);
 138                 do {
 139                         if (qp->req.state != QP_STATE_DRAIN) {
 140                                 /* comp just finished */
 141                                 spin_unlock_irqrestore(&qp->state_lock,
 142                                                        flags);
 143                                 break;
 144                         }
 145
 146                         if (wqe && ((qp->req.wqe_index !=
 147                                 consumer_index(qp->sq.queue)) ||
 148                                 (wqe->state != wqe_state_posted))) {
 149                                 /* comp not done yet */
 150                                 spin_unlock_irqrestore(&qp->state_lock,
 151                                                        flags);
 152                                 break;
 153                         }
 154
 155                         qp->req.state = QP_STATE_DRAINED;
 156                         spin_unlock_irqrestore(&qp->state_lock, flags);
 157
 158                         if (qp->ibqp.event_handler) {
 159                                 struct ib_event ev;
 160
 161                                 ev.device = qp->ibqp.device;
 162                                 ev.element.qp = &qp->ibqp;
 163                                 ev.event = IB_EVENT_SQ_DRAINED;
 164                                 qp->ibqp.event_handler(&ev,
 165                                         qp->ibqp.qp_context);
 166                         }
 167                 } while (0);
 168         }
 169
 170         if (qp->req.wqe_index == producer_index(qp->sq.queue))
 171                 return NULL;
 172
 173         wqe = addr_from_index(qp->sq.queue, qp->req.wqe_index);
 174
 175         if (unlikely((qp->req.state == QP_STATE_DRAIN ||
 176                       qp->req.state == QP_STATE_DRAINED) &&
 177                      (wqe->state != wqe_state_processing)))
 178                 return NULL;
 179
 180         if (unlikely((wqe->wr.send_flags & IB_SEND_FENCE) &&
 181                      (qp->req.wqe_index != consumer_index(qp->sq.queue)))) {
 182                 qp->req.wait_fence = 1;
 183                 return NULL;
 184         }
 185
 186         wqe->mask = wr_opcode_mask(wqe->wr.opcode, qp);
 187         return wqe;
 188 }
 189
 190 static int next_opcode_rc(struct rxe_qp *qp, u32 opcode, int fits)
 191 {
 192         switch (opcode) {
 193         case IB_WR_RDMA_WRITE:
 194                 if (qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_FIRST ||
 195                     qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_MIDDLE)
 196                         return fits ?
 197                                 IB_OPCODE_RC_RDMA_WRITE_LAST :
 198                                 IB_OPCODE_RC_RDMA_WRITE_MIDDLE;
 199                 else
 200                         return fits ?
 201                                 IB_OPCODE_RC_RDMA_WRITE_ONLY :
 202                                 IB_OPCODE_RC_RDMA_WRITE_FIRST;
 203
 204         case IB_WR_RDMA_WRITE_WITH_IMM:
 205                 if (qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_FIRST ||
 206                     qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_MIDDLE)
 207                         return fits ?
 208                                 IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE :
 209                                 IB_OPCODE_RC_RDMA_WRITE_MIDDLE;
 210                 else
 211                         return fits ?
 212                                 IB_OPCODE_RC_RDMA_WRITE_ONLY_WITH_IMMEDIATE :
 213                                 IB_OPCODE_RC_RDMA_WRITE_FIRST;
 214
 215         case IB_WR_SEND:
 216                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 217                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 218                         return fits ?
 219                                 IB_OPCODE_RC_SEND_LAST :
 220                                 IB_OPCODE_RC_SEND_MIDDLE;
 221                 else
 222                         return fits ?
 223                                 IB_OPCODE_RC_SEND_ONLY :
 224                                 IB_OPCODE_RC_SEND_FIRST;
 225
 226         case IB_WR_SEND_WITH_IMM:
 227                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 228                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 229                         return fits ?
 230                                 IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE :
 231                                 IB_OPCODE_RC_SEND_MIDDLE;
 232                 else
 233                         return fits ?
 234                                 IB_OPCODE_RC_SEND_ONLY_WITH_IMMEDIATE :
 235                                 IB_OPCODE_RC_SEND_FIRST;
 236
 237         case IB_WR_RDMA_READ:
 238                 return IB_OPCODE_RC_RDMA_READ_REQUEST;
 239
 240         case IB_WR_ATOMIC_CMP_AND_SWP:
 241                 return IB_OPCODE_RC_COMPARE_SWAP;
 242
 243         case IB_WR_ATOMIC_FETCH_AND_ADD:
 244                 return IB_OPCODE_RC_FETCH_ADD;
 245
 246         case IB_WR_SEND_WITH_INV:
 247                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 248                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 249                         return fits ? IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE :
 250                                 IB_OPCODE_RC_SEND_MIDDLE;
 251                 else
 252                         return fits ? IB_OPCODE_RC_SEND_ONLY_WITH_INVALIDATE :
 253                                 IB_OPCODE_RC_SEND_FIRST;
 254         case IB_WR_REG_MR:
 255         case IB_WR_LOCAL_INV:
 256                 return opcode;
 257         }
 258
 259         return -EINVAL;
 260 }
 261
 262 static int next_opcode_uc(struct rxe_qp *qp, u32 opcode, int fits)
 263 {
 264         switch (opcode) {
 265         case IB_WR_RDMA_WRITE:
 266                 if (qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_FIRST ||
 267                     qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_MIDDLE)
 268                         return fits ?
 269                                 IB_OPCODE_UC_RDMA_WRITE_LAST :
 270                                 IB_OPCODE_UC_RDMA_WRITE_MIDDLE;
 271                 else
 272                         return fits ?
 273                                 IB_OPCODE_UC_RDMA_WRITE_ONLY :
 274                                 IB_OPCODE_UC_RDMA_WRITE_FIRST;
 275
 276         case IB_WR_RDMA_WRITE_WITH_IMM:
 277                 if (qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_FIRST ||
 278                     qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_MIDDLE)
 279                         return fits ?
 280                                 IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE :
 281                                 IB_OPCODE_UC_RDMA_WRITE_MIDDLE;
 282                 else
 283                         return fits ?
 284                                 IB_OPCODE_UC_RDMA_WRITE_ONLY_WITH_IMMEDIATE :
 285                                 IB_OPCODE_UC_RDMA_WRITE_FIRST;
 286
 287         case IB_WR_SEND:
 288                 if (qp->req.opcode == IB_OPCODE_UC_SEND_FIRST ||
 289                     qp->req.opcode == IB_OPCODE_UC_SEND_MIDDLE)
 290                         return fits ?
 291                                 IB_OPCODE_UC_SEND_LAST :
 292                                 IB_OPCODE_UC_SEND_MIDDLE;
 293                 else
 294                         return fits ?
 295                                 IB_OPCODE_UC_SEND_ONLY :
 296                                 IB_OPCODE_UC_SEND_FIRST;
 297
 298         case IB_WR_SEND_WITH_IMM:
 299                 if (qp->req.opcode == IB_OPCODE_UC_SEND_FIRST ||
 300                     qp->req.opcode == IB_OPCODE_UC_SEND_MIDDLE)
 301                         return fits ?
 302                                 IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE :
 303                                 IB_OPCODE_UC_SEND_MIDDLE;
 304                 else
 305                         return fits ?
 306                                 IB_OPCODE_UC_SEND_ONLY_WITH_IMMEDIATE :
 307                                 IB_OPCODE_UC_SEND_FIRST;
 308         }
 309
 310         return -EINVAL;
 311 }
 312
 313 static int next_opcode(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 314                        u32 opcode)
 315 {
 316         int fits = (wqe->dma.resid <= qp->mtu);
 317
 318         switch (qp_type(qp)) {
 319         case IB_QPT_RC:
 320                 return next_opcode_rc(qp, opcode, fits);
 321
 322         case IB_QPT_UC:
 323                 return next_opcode_uc(qp, opcode, fits);
 324
 325         case IB_QPT_SMI:
 326         case IB_QPT_UD:
 327         case IB_QPT_GSI:
 328                 switch (opcode) {
 329                 case IB_WR_SEND:
 330                         return IB_OPCODE_UD_SEND_ONLY;
 331
 332                 case IB_WR_SEND_WITH_IMM:
 333                         return IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE;
 334                 }
 335                 break;
 336
 337         default:
 338                 break;
 339         }
 340
 341         return -EINVAL;
 342 }
 343
 344 static inline int check_init_depth(struct rxe_qp *qp, struct rxe_send_wqe *wqe)
 345 {
 346         int depth;
 347
 348         if (wqe->has_rd_atomic)
 349                 return 0;
 350
 351         qp->req.need_rd_atomic = 1;
 352         depth = atomic_dec_return(&qp->req.rd_atomic);
 353
 354         if (depth >= 0) {
 355                 qp->req.need_rd_atomic = 0;
 356                 wqe->has_rd_atomic = 1;
 357                 return 0;
 358         }
 359
 360         atomic_inc(&qp->req.rd_atomic);
 361         return -EAGAIN;
 362 }
 363
 364 static inline int get_mtu(struct rxe_qp *qp)
 365 {
 366         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 367
 368         if ((qp_type(qp) == IB_QPT_RC) || (qp_type(qp) == IB_QPT_UC))
 369                 return qp->mtu;
 370
 371         return rxe->port.mtu_cap;
 372 }
 373
 374 static struct sk_buff *init_req_packet(struct rxe_qp *qp,
 375                                        struct rxe_send_wqe *wqe,
 376                                        int opcode, int payload,
 377                                        struct rxe_pkt_info *pkt)
 378 {
 379         struct rxe_dev          *rxe = to_rdev(qp->ibqp.device);
 380         struct rxe_port         *port = &rxe->port;
 381         struct sk_buff          *skb;
 382         struct rxe_send_wr      *ibwr = &wqe->wr;
 383         struct rxe_av           *av;
 384         int                     pad = (-payload) & 0x3;
 385         int                     paylen;
 386         int                     solicited;
 387         u16                     pkey;
 388         u32                     qp_num;
 389         int                     ack_req;
 390
 391         /* length from start of bth to end of icrc */
 392         paylen = rxe_opcode[opcode].length + payload + pad + RXE_ICRC_SIZE;
 393
 394         /* pkt->hdr, rxe, port_num and mask are initialized in ifc
 395          * layer
 396          */
 397         pkt->opcode     = opcode;
 398         pkt->qp         = qp;
 399         pkt->psn        = qp->req.psn;
 400         pkt->mask       = rxe_opcode[opcode].mask;
 401         pkt->paylen     = paylen;
 402         pkt->offset     = 0;
 403         pkt->wqe        = wqe;
 404
 405         /* init skb */
 406         av = rxe_get_av(pkt);
 407         skb = rxe_init_packet(rxe, av, paylen, pkt);
 408         if (unlikely(!skb))
 409                 return NULL;
 410
 411         /* init bth */
 412         solicited = (ibwr->send_flags & IB_SEND_SOLICITED) &&
 413                         (pkt->mask & RXE_END_MASK) &&
 414                         ((pkt->mask & (RXE_SEND_MASK)) ||
 415                         (pkt->mask & (RXE_WRITE_MASK | RXE_IMMDT_MASK)) ==
 416                         (RXE_WRITE_MASK | RXE_IMMDT_MASK));
 417
 418         pkey = (qp_type(qp) == IB_QPT_GSI) ?
 419                  port->pkey_tbl[ibwr->wr.ud.pkey_index] :
 420                  port->pkey_tbl[qp->attr.pkey_index];
 421
 422         qp_num = (pkt->mask & RXE_DETH_MASK) ? ibwr->wr.ud.remote_qpn :
 423                                          qp->attr.dest_qp_num;
 424
 425         ack_req = ((pkt->mask & RXE_END_MASK) ||
 426                 (qp->req.noack_pkts++ > RXE_MAX_PKT_PER_ACK));
 427         if (ack_req)
 428                 qp->req.noack_pkts = 0;
 429
 430         bth_init(pkt, pkt->opcode, solicited, 0, pad, pkey, qp_num,
 431                  ack_req, pkt->psn);
 432
 433         /* init optional headers */
 434         if (pkt->mask & RXE_RETH_MASK) {
 435                 reth_set_rkey(pkt, ibwr->wr.rdma.rkey);
 436                 reth_set_va(pkt, wqe->iova);
 437                 reth_set_len(pkt, wqe->dma.length);
 438         }
 439
 440         if (pkt->mask & RXE_IMMDT_MASK)
 441                 immdt_set_imm(pkt, ibwr->ex.imm_data);
 442
 443         if (pkt->mask & RXE_IETH_MASK)
 444                 ieth_set_rkey(pkt, ibwr->ex.invalidate_rkey);
 445
 446         if (pkt->mask & RXE_ATMETH_MASK) {
 447                 atmeth_set_va(pkt, wqe->iova);
 448                 if (opcode == IB_OPCODE_RC_COMPARE_SWAP ||
 449                     opcode == IB_OPCODE_RD_COMPARE_SWAP) {
 450                         atmeth_set_swap_add(pkt, ibwr->wr.atomic.swap);
 451                         atmeth_set_comp(pkt, ibwr->wr.atomic.compare_add);
 452                 } else {
 453                         atmeth_set_swap_add(pkt, ibwr->wr.atomic.compare_add);
 454                 }
 455                 atmeth_set_rkey(pkt, ibwr->wr.atomic.rkey);
 456         }
 457
 458         if (pkt->mask & RXE_DETH_MASK) {
 459                 if (qp->ibqp.qp_num == 1)
 460                         deth_set_qkey(pkt, GSI_QKEY);
 461                 else
 462                         deth_set_qkey(pkt, ibwr->wr.ud.remote_qkey);
 463                 deth_set_sqp(pkt, qp->ibqp.qp_num);
 464         }
 465
 466         return skb;
 467 }
 468
 469 static int fill_packet(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 470                        struct rxe_pkt_info *pkt, struct sk_buff *skb,
 471                        int paylen)
 472 {
 473         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 474         u32 crc = 0;
 475         u32 *p;
 476         int err;
 477
 478         err = rxe_prepare(rxe, pkt, skb, &crc);
 479         if (err)
 480                 return err;
 481
 482         if (pkt->mask & RXE_WRITE_OR_SEND) {
 483                 if (wqe->wr.send_flags & IB_SEND_INLINE) {
 484                         u8 *tmp = &wqe->dma.inline_data[wqe->dma.sge_offset];
 485
 486                         crc = crc32_le(crc, tmp, paylen);
 487
 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))
 598                 goto exit;
 599
 600         if (unlikely(qp->req.state == QP_STATE_ERROR)) {
 601                 rxe_drain_req_pkts(qp, true);
 602                 goto exit;
 603         }
 604
 605         if (unlikely(qp->req.state == QP_STATE_RESET)) {
 606                 qp->req.wqe_index = consumer_index(qp->sq.queue);
 607                 qp->req.opcode = -1;
 608                 qp->req.need_rd_atomic = 0;
 609                 qp->req.wait_psn = 0;
 610                 qp->req.need_retry = 0;
 611                 goto exit;
 612         }
 613
 614         if (unlikely(qp->req.need_retry)) {
 615                 req_retry(qp);
 616                 qp->req.need_retry = 0;
 617         }
 618
 619         wqe = req_next_wqe(qp);
 620         if (unlikely(!wqe))
 621                 goto exit;
 622
 623         if (wqe->mask & WR_REG_MASK) {
 624                 if (wqe->wr.opcode == IB_WR_LOCAL_INV) {
 625                         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 626                         struct rxe_mem *rmr;
 627
 628                         rmr = rxe_pool_get_index(&rxe->mr_pool,
 629                                                  wqe->wr.ex.invalidate_rkey >> 8);
 630                         if (!rmr) {
 631                                 pr_err("No mr for key %#x\n",
 632                                        wqe->wr.ex.invalidate_rkey);
 633                                 wqe->state = wqe_state_error;
 634                                 wqe->status = IB_WC_MW_BIND_ERR;
 635                                 goto exit;
 636                         }
 637                         rmr->state = RXE_MEM_STATE_FREE;
 638                         rxe_drop_ref(rmr);
 639                         wqe->state = wqe_state_done;
 640                         wqe->status = IB_WC_SUCCESS;
 641                 } else if (wqe->wr.opcode == IB_WR_REG_MR) {
 642                         struct rxe_mem *rmr = to_rmr(wqe->wr.wr.reg.mr);
 643
 644                         rmr->state = RXE_MEM_STATE_VALID;
 645                         rmr->access = wqe->wr.wr.reg.access;
 646                         rmr->lkey = wqe->wr.wr.reg.key;
 647                         rmr->rkey = wqe->wr.wr.reg.key;
 648                         wqe->state = wqe_state_done;
 649                         wqe->status = IB_WC_SUCCESS;
 650                 } else {
 651                         goto exit;
 652                 }
 653                 qp->req.wqe_index = next_index(qp->sq.queue,
 654                                                 qp->req.wqe_index);
 655                 goto next_wqe;
 656         }
 657
 658         if (unlikely(qp_type(qp) == IB_QPT_RC &&
 659                      qp->req.psn > (qp->comp.psn + RXE_MAX_UNACKED_PSNS))) {
 660                 qp->req.wait_psn = 1;
 661                 goto exit;
 662         }
 663
 664         /* Limit the number of inflight SKBs per QP */
 665         if (unlikely(atomic_read(&qp->skb_out) >
 666                      RXE_INFLIGHT_SKBS_PER_QP_HIGH)) {
 667                 qp->need_req_skb = 1;
 668                 goto exit;
 669         }
 670
 671         opcode = next_opcode(qp, wqe, wqe->wr.opcode);
 672         if (unlikely(opcode < 0)) {
 673                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 674                 goto exit;
 675         }
 676
 677         mask = rxe_opcode[opcode].mask;
 678         if (unlikely(mask & RXE_READ_OR_ATOMIC)) {
 679                 if (check_init_depth(qp, wqe))
 680                         goto exit;
 681         }
 682
 683         mtu = get_mtu(qp);
 684         payload = (mask & RXE_WRITE_OR_SEND) ? wqe->dma.resid : 0;
 685         if (payload > mtu) {
 686                 if (qp_type(qp) == IB_QPT_UD) {
 687                         /* C10-93.1.1: If the total sum of all the buffer lengths specified for a
 688                          * UD message exceeds the MTU of the port as returned by QueryHCA, the CI
 689                          * shall not emit any packets for this message. Further, the CI shall not
 690                          * generate an error due to this condition.
 691                          */
 692
 693                         /* fake a successful UD send */
 694                         wqe->first_psn = qp->req.psn;
 695                         wqe->last_psn = qp->req.psn;
 696                         qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK;
 697                         qp->req.opcode = IB_OPCODE_UD_SEND_ONLY;
 698                         qp->req.wqe_index = next_index(qp->sq.queue,
 699                                                        qp->req.wqe_index);
 700                         wqe->state = wqe_state_done;
 701                         wqe->status = IB_WC_SUCCESS;
 702                         __rxe_do_task(&qp->comp.task);
 703                         rxe_drop_ref(qp);
 704                         return 0;
 705                 }
 706                 payload = mtu;
 707         }
 708
 709         skb = init_req_packet(qp, wqe, opcode, payload, &pkt);
 710         if (unlikely(!skb)) {
 711                 pr_err("qp#%d Failed allocating skb\n", qp_num(qp));
 712                 goto err;
 713         }
 714
 715         if (fill_packet(qp, wqe, &pkt, skb, payload)) {
 716                 pr_debug("qp#%d Error during fill packet\n", qp_num(qp));
 717                 goto err;
 718         }
 719
 720         /*
 721          * To prevent a race on wqe access between requester and completer,
 722          * wqe members state and psn need to be set before calling
 723          * rxe_xmit_packet().
 724          * Otherwise, completer might initiate an unjustified retry flow.
 725          */
 726         save_state(wqe, qp, &rollback_wqe, &rollback_psn);
 727         update_wqe_state(qp, wqe, &pkt);
 728         update_wqe_psn(qp, wqe, &pkt, payload);
 729         ret = rxe_xmit_packet(to_rdev(qp->ibqp.device), qp, &pkt, skb);
 730         if (ret) {
 731                 qp->need_req_skb = 1;
 732
 733                 rollback_state(wqe, qp, &rollback_wqe, rollback_psn);
 734
 735                 if (ret == -EAGAIN) {
 736                         kfree_skb(skb);
 737                         rxe_run_task(&qp->req.task, 1);
 738                         goto exit;
 739                 }
 740
 741                 goto err;
 742         }
 743
 744         update_state(qp, wqe, &pkt, payload);
 745
 746         goto next_wqe;
 747
 748 err:
 749         kfree_skb(skb);
 750         wqe->status = IB_WC_LOC_PROT_ERR;
 751         wqe->state = wqe_state_error;
 752         __rxe_do_task(&qp->comp.task);
 753
 754 exit:
 755         rxe_drop_ref(qp);
 756         return -EAGAIN;
 757 }