drivers/infiniband/sw/rxe/rxe_req.c

   1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
   2 /*
   3  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
   4  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
   5  */
   6
   7 #include <linux/skbuff.h>
   8 #include <crypto/hash.h>
   9
  10 #include "rxe.h"
  11 #include "rxe_loc.h"
  12 #include "rxe_queue.h"
  13
  14 static int next_opcode(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
  15                        u32 opcode);
  16
  17 static inline void retry_first_write_send(struct rxe_qp *qp,
  18                                           struct rxe_send_wqe *wqe, int npsn)
  19 {
  20         int i;
  21
  22         for (i = 0; i < npsn; i++) {
  23                 int to_send = (wqe->dma.resid > qp->mtu) ?
  24                                 qp->mtu : wqe->dma.resid;
  25
  26                 qp->req.opcode = next_opcode(qp, wqe,
  27                                              wqe->wr.opcode);
  28
  29                 if (wqe->wr.send_flags & IB_SEND_INLINE) {
  30                         wqe->dma.resid -= to_send;
  31                         wqe->dma.sge_offset += to_send;
  32                 } else {
  33                         advance_dma_data(&wqe->dma, to_send);
  34                 }
  35         }
  36 }
  37
  38 static void req_retry(struct rxe_qp *qp)
  39 {
  40         struct rxe_send_wqe *wqe;
  41         unsigned int wqe_index;
  42         unsigned int mask;
  43         int npsn;
  44         int first = 1;
  45         struct rxe_queue *q = qp->sq.queue;
  46         unsigned int cons;
  47         unsigned int prod;
  48
  49         cons = queue_get_consumer(q, QUEUE_TYPE_FROM_CLIENT);
  50         prod = queue_get_producer(q, QUEUE_TYPE_FROM_CLIENT);
  51
  52         qp->req.wqe_index       = cons;
  53         qp->req.psn             = qp->comp.psn;
  54         qp->req.opcode          = -1;
  55
  56         for (wqe_index = cons; wqe_index != prod;
  57                         wqe_index = queue_next_index(q, wqe_index)) {
  58                 wqe = queue_addr_from_index(qp->sq.queue, wqe_index);
  59                 mask = wr_opcode_mask(wqe->wr.opcode, qp);
  60
  61                 if (wqe->state == wqe_state_posted)
  62                         break;
  63
  64                 if (wqe->state == wqe_state_done)
  65                         continue;
  66
  67                 wqe->iova = (mask & WR_ATOMIC_MASK) ?
  68                              wqe->wr.wr.atomic.remote_addr :
  69                              (mask & WR_READ_OR_WRITE_MASK) ?
  70                              wqe->wr.wr.rdma.remote_addr :
  71                              0;
  72
  73                 if (!first || (mask & WR_READ_MASK) == 0) {
  74                         wqe->dma.resid = wqe->dma.length;
  75                         wqe->dma.cur_sge = 0;
  76                         wqe->dma.sge_offset = 0;
  77                 }
  78
  79                 if (first) {
  80                         first = 0;
  81
  82                         if (mask & WR_WRITE_OR_SEND_MASK) {
  83                                 npsn = (qp->comp.psn - wqe->first_psn) &
  84                                         BTH_PSN_MASK;
  85                                 retry_first_write_send(qp, wqe, npsn);
  86                         }
  87
  88                         if (mask & WR_READ_MASK) {
  89                                 npsn = (wqe->dma.length - wqe->dma.resid) /
  90                                         qp->mtu;
  91                                 wqe->iova += npsn * qp->mtu;
  92                         }
  93                 }
  94
  95                 wqe->state = wqe_state_posted;
  96         }
  97 }
  98
  99 void rnr_nak_timer(struct timer_list *t)
 100 {
 101         struct rxe_qp *qp = from_timer(qp, t, rnr_nak_timer);
 102         unsigned long flags;
 103
 104         rxe_dbg_qp(qp, "nak timer fired\n");
 105
 106         spin_lock_irqsave(&qp->state_lock, flags);
 107         if (qp->valid) {
 108                 /* request a send queue retry */
 109                 qp->req.need_retry = 1;
 110                 qp->req.wait_for_rnr_timer = 0;
 111                 rxe_sched_task(&qp->req.task);
 112         }
 113         spin_unlock_irqrestore(&qp->state_lock, flags);
 114 }
 115
 116 static void req_check_sq_drain_done(struct rxe_qp *qp)
 117 {
 118         struct rxe_queue *q;
 119         unsigned int index;
 120         unsigned int cons;
 121         struct rxe_send_wqe *wqe;
 122         unsigned long flags;
 123
 124         spin_lock_irqsave(&qp->state_lock, flags);
 125         if (qp_state(qp) == IB_QPS_SQD) {
 126                 q = qp->sq.queue;
 127                 index = qp->req.wqe_index;
 128                 cons = queue_get_consumer(q, QUEUE_TYPE_FROM_CLIENT);
 129                 wqe = queue_addr_from_index(q, cons);
 130
 131                 /* check to see if we are drained;
 132                  * state_lock used by requester and completer
 133                  */
 134                 do {
 135                         if (!qp->attr.sq_draining)
 136                                 /* comp just finished */
 137                                 break;
 138
 139                         if (wqe && ((index != cons) ||
 140                                 (wqe->state != wqe_state_posted)))
 141                                 /* comp not done yet */
 142                                 break;
 143
 144                         qp->attr.sq_draining = 0;
 145                         spin_unlock_irqrestore(&qp->state_lock, flags);
 146
 147                         if (qp->ibqp.event_handler) {
 148                                 struct ib_event ev;
 149
 150                                 ev.device = qp->ibqp.device;
 151                                 ev.element.qp = &qp->ibqp;
 152                                 ev.event = IB_EVENT_SQ_DRAINED;
 153                                 qp->ibqp.event_handler(&ev,
 154                                         qp->ibqp.qp_context);
 155                         }
 156                         return;
 157                 } while (0);
 158         }
 159         spin_unlock_irqrestore(&qp->state_lock, flags);
 160 }
 161
 162 static struct rxe_send_wqe *__req_next_wqe(struct rxe_qp *qp)
 163 {
 164         struct rxe_queue *q = qp->sq.queue;
 165         unsigned int index = qp->req.wqe_index;
 166         unsigned int prod;
 167
 168         prod = queue_get_producer(q, QUEUE_TYPE_FROM_CLIENT);
 169         if (index == prod)
 170                 return NULL;
 171         else
 172                 return queue_addr_from_index(q, index);
 173 }
 174
 175 static struct rxe_send_wqe *req_next_wqe(struct rxe_qp *qp)
 176 {
 177         struct rxe_send_wqe *wqe;
 178         unsigned long flags;
 179
 180         req_check_sq_drain_done(qp);
 181
 182         wqe = __req_next_wqe(qp);
 183         if (wqe == NULL)
 184                 return NULL;
 185
 186         spin_lock_irqsave(&qp->state_lock, flags);
 187         if (unlikely((qp_state(qp) == IB_QPS_SQD) &&
 188                      (wqe->state != wqe_state_processing))) {
 189                 spin_unlock_irqrestore(&qp->state_lock, flags);
 190                 return NULL;
 191         }
 192         spin_unlock_irqrestore(&qp->state_lock, flags);
 193
 194         wqe->mask = wr_opcode_mask(wqe->wr.opcode, qp);
 195         return wqe;
 196 }
 197
 198 /**
 199  * rxe_wqe_is_fenced - check if next wqe is fenced
 200  * @qp: the queue pair
 201  * @wqe: the next wqe
 202  *
 203  * Returns: 1 if wqe needs to wait
 204  *          0 if wqe is ready to go
 205  */
 206 static int rxe_wqe_is_fenced(struct rxe_qp *qp, struct rxe_send_wqe *wqe)
 207 {
 208         /* Local invalidate fence (LIF) see IBA 10.6.5.1
 209          * Requires ALL previous operations on the send queue
 210          * are complete. Make mandatory for the rxe driver.
 211          */
 212         if (wqe->wr.opcode == IB_WR_LOCAL_INV)
 213                 return qp->req.wqe_index != queue_get_consumer(qp->sq.queue,
 214                                                 QUEUE_TYPE_FROM_CLIENT);
 215
 216         /* Fence see IBA 10.8.3.3
 217          * Requires that all previous read and atomic operations
 218          * are complete.
 219          */
 220         return (wqe->wr.send_flags & IB_SEND_FENCE) &&
 221                 atomic_read(&qp->req.rd_atomic) != qp->attr.max_rd_atomic;
 222 }
 223
 224 static int next_opcode_rc(struct rxe_qp *qp, u32 opcode, int fits)
 225 {
 226         switch (opcode) {
 227         case IB_WR_RDMA_WRITE:
 228                 if (qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_FIRST ||
 229                     qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_MIDDLE)
 230                         return fits ?
 231                                 IB_OPCODE_RC_RDMA_WRITE_LAST :
 232                                 IB_OPCODE_RC_RDMA_WRITE_MIDDLE;
 233                 else
 234                         return fits ?
 235                                 IB_OPCODE_RC_RDMA_WRITE_ONLY :
 236                                 IB_OPCODE_RC_RDMA_WRITE_FIRST;
 237
 238         case IB_WR_RDMA_WRITE_WITH_IMM:
 239                 if (qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_FIRST ||
 240                     qp->req.opcode == IB_OPCODE_RC_RDMA_WRITE_MIDDLE)
 241                         return fits ?
 242                                 IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE :
 243                                 IB_OPCODE_RC_RDMA_WRITE_MIDDLE;
 244                 else
 245                         return fits ?
 246                                 IB_OPCODE_RC_RDMA_WRITE_ONLY_WITH_IMMEDIATE :
 247                                 IB_OPCODE_RC_RDMA_WRITE_FIRST;
 248
 249         case IB_WR_SEND:
 250                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 251                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 252                         return fits ?
 253                                 IB_OPCODE_RC_SEND_LAST :
 254                                 IB_OPCODE_RC_SEND_MIDDLE;
 255                 else
 256                         return fits ?
 257                                 IB_OPCODE_RC_SEND_ONLY :
 258                                 IB_OPCODE_RC_SEND_FIRST;
 259
 260         case IB_WR_SEND_WITH_IMM:
 261                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 262                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 263                         return fits ?
 264                                 IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE :
 265                                 IB_OPCODE_RC_SEND_MIDDLE;
 266                 else
 267                         return fits ?
 268                                 IB_OPCODE_RC_SEND_ONLY_WITH_IMMEDIATE :
 269                                 IB_OPCODE_RC_SEND_FIRST;
 270
 271         case IB_WR_FLUSH:
 272                 return IB_OPCODE_RC_FLUSH;
 273
 274         case IB_WR_RDMA_READ:
 275                 return IB_OPCODE_RC_RDMA_READ_REQUEST;
 276
 277         case IB_WR_ATOMIC_CMP_AND_SWP:
 278                 return IB_OPCODE_RC_COMPARE_SWAP;
 279
 280         case IB_WR_ATOMIC_FETCH_AND_ADD:
 281                 return IB_OPCODE_RC_FETCH_ADD;
 282
 283         case IB_WR_SEND_WITH_INV:
 284                 if (qp->req.opcode == IB_OPCODE_RC_SEND_FIRST ||
 285                     qp->req.opcode == IB_OPCODE_RC_SEND_MIDDLE)
 286                         return fits ? IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE :
 287                                 IB_OPCODE_RC_SEND_MIDDLE;
 288                 else
 289                         return fits ? IB_OPCODE_RC_SEND_ONLY_WITH_INVALIDATE :
 290                                 IB_OPCODE_RC_SEND_FIRST;
 291
 292         case IB_WR_ATOMIC_WRITE:
 293                 return IB_OPCODE_RC_ATOMIC_WRITE;
 294
 295         case IB_WR_REG_MR:
 296         case IB_WR_LOCAL_INV:
 297                 return opcode;
 298         }
 299
 300         return -EINVAL;
 301 }
 302
 303 static int next_opcode_uc(struct rxe_qp *qp, u32 opcode, int fits)
 304 {
 305         switch (opcode) {
 306         case IB_WR_RDMA_WRITE:
 307                 if (qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_FIRST ||
 308                     qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_MIDDLE)
 309                         return fits ?
 310                                 IB_OPCODE_UC_RDMA_WRITE_LAST :
 311                                 IB_OPCODE_UC_RDMA_WRITE_MIDDLE;
 312                 else
 313                         return fits ?
 314                                 IB_OPCODE_UC_RDMA_WRITE_ONLY :
 315                                 IB_OPCODE_UC_RDMA_WRITE_FIRST;
 316
 317         case IB_WR_RDMA_WRITE_WITH_IMM:
 318                 if (qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_FIRST ||
 319                     qp->req.opcode == IB_OPCODE_UC_RDMA_WRITE_MIDDLE)
 320                         return fits ?
 321                                 IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE :
 322                                 IB_OPCODE_UC_RDMA_WRITE_MIDDLE;
 323                 else
 324                         return fits ?
 325                                 IB_OPCODE_UC_RDMA_WRITE_ONLY_WITH_IMMEDIATE :
 326                                 IB_OPCODE_UC_RDMA_WRITE_FIRST;
 327
 328         case IB_WR_SEND:
 329                 if (qp->req.opcode == IB_OPCODE_UC_SEND_FIRST ||
 330                     qp->req.opcode == IB_OPCODE_UC_SEND_MIDDLE)
 331                         return fits ?
 332                                 IB_OPCODE_UC_SEND_LAST :
 333                                 IB_OPCODE_UC_SEND_MIDDLE;
 334                 else
 335                         return fits ?
 336                                 IB_OPCODE_UC_SEND_ONLY :
 337                                 IB_OPCODE_UC_SEND_FIRST;
 338
 339         case IB_WR_SEND_WITH_IMM:
 340                 if (qp->req.opcode == IB_OPCODE_UC_SEND_FIRST ||
 341                     qp->req.opcode == IB_OPCODE_UC_SEND_MIDDLE)
 342                         return fits ?
 343                                 IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE :
 344                                 IB_OPCODE_UC_SEND_MIDDLE;
 345                 else
 346                         return fits ?
 347                                 IB_OPCODE_UC_SEND_ONLY_WITH_IMMEDIATE :
 348                                 IB_OPCODE_UC_SEND_FIRST;
 349         }
 350
 351         return -EINVAL;
 352 }
 353
 354 static int next_opcode(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 355                        u32 opcode)
 356 {
 357         int fits = (wqe->dma.resid <= qp->mtu);
 358
 359         switch (qp_type(qp)) {
 360         case IB_QPT_RC:
 361                 return next_opcode_rc(qp, opcode, fits);
 362
 363         case IB_QPT_UC:
 364                 return next_opcode_uc(qp, opcode, fits);
 365
 366         case IB_QPT_UD:
 367         case IB_QPT_GSI:
 368                 switch (opcode) {
 369                 case IB_WR_SEND:
 370                         return IB_OPCODE_UD_SEND_ONLY;
 371
 372                 case IB_WR_SEND_WITH_IMM:
 373                         return IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE;
 374                 }
 375                 break;
 376
 377         default:
 378                 break;
 379         }
 380
 381         return -EINVAL;
 382 }
 383
 384 static inline int check_init_depth(struct rxe_qp *qp, struct rxe_send_wqe *wqe)
 385 {
 386         int depth;
 387
 388         if (wqe->has_rd_atomic)
 389                 return 0;
 390
 391         qp->req.need_rd_atomic = 1;
 392         depth = atomic_dec_return(&qp->req.rd_atomic);
 393
 394         if (depth >= 0) {
 395                 qp->req.need_rd_atomic = 0;
 396                 wqe->has_rd_atomic = 1;
 397                 return 0;
 398         }
 399
 400         atomic_inc(&qp->req.rd_atomic);
 401         return -EAGAIN;
 402 }
 403
 404 static inline int get_mtu(struct rxe_qp *qp)
 405 {
 406         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 407
 408         if ((qp_type(qp) == IB_QPT_RC) || (qp_type(qp) == IB_QPT_UC))
 409                 return qp->mtu;
 410
 411         return rxe->port.mtu_cap;
 412 }
 413
 414 static struct sk_buff *init_req_packet(struct rxe_qp *qp,
 415                                        struct rxe_av *av,
 416                                        struct rxe_send_wqe *wqe,
 417                                        int opcode, u32 payload,
 418                                        struct rxe_pkt_info *pkt)
 419 {
 420         struct rxe_dev          *rxe = to_rdev(qp->ibqp.device);
 421         struct sk_buff          *skb;
 422         struct rxe_send_wr      *ibwr = &wqe->wr;
 423         int                     pad = (-payload) & 0x3;
 424         int                     paylen;
 425         int                     solicited;
 426         u32                     qp_num;
 427         int                     ack_req;
 428
 429         /* length from start of bth to end of icrc */
 430         paylen = rxe_opcode[opcode].length + payload + pad + RXE_ICRC_SIZE;
 431         pkt->paylen = paylen;
 432
 433         /* init skb */
 434         skb = rxe_init_packet(rxe, av, paylen, pkt);
 435         if (unlikely(!skb))
 436                 return NULL;
 437
 438         /* init bth */
 439         solicited = (ibwr->send_flags & IB_SEND_SOLICITED) &&
 440                         (pkt->mask & RXE_END_MASK) &&
 441                         ((pkt->mask & (RXE_SEND_MASK)) ||
 442                         (pkt->mask & (RXE_WRITE_MASK | RXE_IMMDT_MASK)) ==
 443                         (RXE_WRITE_MASK | RXE_IMMDT_MASK));
 444
 445         qp_num = (pkt->mask & RXE_DETH_MASK) ? ibwr->wr.ud.remote_qpn :
 446                                          qp->attr.dest_qp_num;
 447
 448         ack_req = ((pkt->mask & RXE_END_MASK) ||
 449                 (qp->req.noack_pkts++ > RXE_MAX_PKT_PER_ACK));
 450         if (ack_req)
 451                 qp->req.noack_pkts = 0;
 452
 453         bth_init(pkt, pkt->opcode, solicited, 0, pad, IB_DEFAULT_PKEY_FULL, qp_num,
 454                  ack_req, pkt->psn);
 455
 456         /* init optional headers */
 457         if (pkt->mask & RXE_RETH_MASK) {
 458                 if (pkt->mask & RXE_FETH_MASK)
 459                         reth_set_rkey(pkt, ibwr->wr.flush.rkey);
 460                 else
 461                         reth_set_rkey(pkt, ibwr->wr.rdma.rkey);
 462                 reth_set_va(pkt, wqe->iova);
 463                 reth_set_len(pkt, wqe->dma.resid);
 464         }
 465
 466         /* Fill Flush Extension Transport Header */
 467         if (pkt->mask & RXE_FETH_MASK)
 468                 feth_init(pkt, ibwr->wr.flush.type, ibwr->wr.flush.level);
 469
 470         if (pkt->mask & RXE_IMMDT_MASK)
 471                 immdt_set_imm(pkt, ibwr->ex.imm_data);
 472
 473         if (pkt->mask & RXE_IETH_MASK)
 474                 ieth_set_rkey(pkt, ibwr->ex.invalidate_rkey);
 475
 476         if (pkt->mask & RXE_ATMETH_MASK) {
 477                 atmeth_set_va(pkt, wqe->iova);
 478                 if (opcode == IB_OPCODE_RC_COMPARE_SWAP) {
 479                         atmeth_set_swap_add(pkt, ibwr->wr.atomic.swap);
 480                         atmeth_set_comp(pkt, ibwr->wr.atomic.compare_add);
 481                 } else {
 482                         atmeth_set_swap_add(pkt, ibwr->wr.atomic.compare_add);
 483                 }
 484                 atmeth_set_rkey(pkt, ibwr->wr.atomic.rkey);
 485         }
 486
 487         if (pkt->mask & RXE_DETH_MASK) {
 488                 if (qp->ibqp.qp_num == 1)
 489                         deth_set_qkey(pkt, GSI_QKEY);
 490                 else
 491                         deth_set_qkey(pkt, ibwr->wr.ud.remote_qkey);
 492                 deth_set_sqp(pkt, qp->ibqp.qp_num);
 493         }
 494
 495         return skb;
 496 }
 497
 498 static int finish_packet(struct rxe_qp *qp, struct rxe_av *av,
 499                          struct rxe_send_wqe *wqe, struct rxe_pkt_info *pkt,
 500                          struct sk_buff *skb, u32 payload)
 501 {
 502         int err;
 503
 504         err = rxe_prepare(av, pkt, skb);
 505         if (err)
 506                 return err;
 507
 508         if (pkt->mask & RXE_WRITE_OR_SEND_MASK) {
 509                 if (wqe->wr.send_flags & IB_SEND_INLINE) {
 510                         u8 *tmp = &wqe->dma.inline_data[wqe->dma.sge_offset];
 511
 512                         memcpy(payload_addr(pkt), tmp, payload);
 513
 514                         wqe->dma.resid -= payload;
 515                         wqe->dma.sge_offset += payload;
 516                 } else {
 517                         err = copy_data(qp->pd, 0, &wqe->dma,
 518                                         payload_addr(pkt), payload,
 519                                         RXE_FROM_MR_OBJ);
 520                         if (err)
 521                                 return err;
 522                 }
 523                 if (bth_pad(pkt)) {
 524                         u8 *pad = payload_addr(pkt) + payload;
 525
 526                         memset(pad, 0, bth_pad(pkt));
 527                 }
 528         } else if (pkt->mask & RXE_FLUSH_MASK) {
 529                 /* oA19-2: shall have no payload. */
 530                 wqe->dma.resid = 0;
 531         }
 532
 533         if (pkt->mask & RXE_ATOMIC_WRITE_MASK) {
 534                 memcpy(payload_addr(pkt), wqe->dma.atomic_wr, payload);
 535                 wqe->dma.resid -= payload;
 536         }
 537
 538         return 0;
 539 }
 540
 541 static void update_wqe_state(struct rxe_qp *qp,
 542                 struct rxe_send_wqe *wqe,
 543                 struct rxe_pkt_info *pkt)
 544 {
 545         if (pkt->mask & RXE_END_MASK) {
 546                 if (qp_type(qp) == IB_QPT_RC)
 547                         wqe->state = wqe_state_pending;
 548         } else {
 549                 wqe->state = wqe_state_processing;
 550         }
 551 }
 552
 553 static void update_wqe_psn(struct rxe_qp *qp,
 554                            struct rxe_send_wqe *wqe,
 555                            struct rxe_pkt_info *pkt,
 556                            u32 payload)
 557 {
 558         /* number of packets left to send including current one */
 559         int num_pkt = (wqe->dma.resid + payload + qp->mtu - 1) / qp->mtu;
 560
 561         /* handle zero length packet case */
 562         if (num_pkt == 0)
 563                 num_pkt = 1;
 564
 565         if (pkt->mask & RXE_START_MASK) {
 566                 wqe->first_psn = qp->req.psn;
 567                 wqe->last_psn = (qp->req.psn + num_pkt - 1) & BTH_PSN_MASK;
 568         }
 569
 570         if (pkt->mask & RXE_READ_MASK)
 571                 qp->req.psn = (wqe->first_psn + num_pkt) & BTH_PSN_MASK;
 572         else
 573                 qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK;
 574 }
 575
 576 static void save_state(struct rxe_send_wqe *wqe,
 577                        struct rxe_qp *qp,
 578                        struct rxe_send_wqe *rollback_wqe,
 579                        u32 *rollback_psn)
 580 {
 581         rollback_wqe->state     = wqe->state;
 582         rollback_wqe->first_psn = wqe->first_psn;
 583         rollback_wqe->last_psn  = wqe->last_psn;
 584         *rollback_psn           = qp->req.psn;
 585 }
 586
 587 static void rollback_state(struct rxe_send_wqe *wqe,
 588                            struct rxe_qp *qp,
 589                            struct rxe_send_wqe *rollback_wqe,
 590                            u32 rollback_psn)
 591 {
 592         wqe->state     = rollback_wqe->state;
 593         wqe->first_psn = rollback_wqe->first_psn;
 594         wqe->last_psn  = rollback_wqe->last_psn;
 595         qp->req.psn    = rollback_psn;
 596 }
 597
 598 static void update_state(struct rxe_qp *qp, struct rxe_pkt_info *pkt)
 599 {
 600         qp->req.opcode = pkt->opcode;
 601
 602         if (pkt->mask & RXE_END_MASK)
 603                 qp->req.wqe_index = queue_next_index(qp->sq.queue,
 604                                                      qp->req.wqe_index);
 605
 606         qp->need_req_skb = 0;
 607
 608         if (qp->qp_timeout_jiffies && !timer_pending(&qp->retrans_timer))
 609                 mod_timer(&qp->retrans_timer,
 610                           jiffies + qp->qp_timeout_jiffies);
 611 }
 612
 613 static int rxe_do_local_ops(struct rxe_qp *qp, struct rxe_send_wqe *wqe)
 614 {
 615         u8 opcode = wqe->wr.opcode;
 616         u32 rkey;
 617         int ret;
 618
 619         switch (opcode) {
 620         case IB_WR_LOCAL_INV:
 621                 rkey = wqe->wr.ex.invalidate_rkey;
 622                 if (rkey_is_mw(rkey))
 623                         ret = rxe_invalidate_mw(qp, rkey);
 624                 else
 625                         ret = rxe_invalidate_mr(qp, rkey);
 626
 627                 if (unlikely(ret)) {
 628                         wqe->status = IB_WC_LOC_QP_OP_ERR;
 629                         return ret;
 630                 }
 631                 break;
 632         case IB_WR_REG_MR:
 633                 ret = rxe_reg_fast_mr(qp, wqe);
 634                 if (unlikely(ret)) {
 635                         wqe->status = IB_WC_LOC_QP_OP_ERR;
 636                         return ret;
 637                 }
 638                 break;
 639         case IB_WR_BIND_MW:
 640                 ret = rxe_bind_mw(qp, wqe);
 641                 if (unlikely(ret)) {
 642                         wqe->status = IB_WC_MW_BIND_ERR;
 643                         return ret;
 644                 }
 645                 break;
 646         default:
 647                 rxe_dbg_qp(qp, "Unexpected send wqe opcode %d\n", opcode);
 648                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 649                 return -EINVAL;
 650         }
 651
 652         wqe->state = wqe_state_done;
 653         wqe->status = IB_WC_SUCCESS;
 654         qp->req.wqe_index = queue_next_index(qp->sq.queue, qp->req.wqe_index);
 655
 656         /* There is no ack coming for local work requests
 657          * which can lead to a deadlock. So go ahead and complete
 658          * it now.
 659          */
 660         rxe_sched_task(&qp->comp.task);
 661
 662         return 0;
 663 }
 664
 665 int rxe_requester(struct rxe_qp *qp)
 666 {
 667         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 668         struct rxe_pkt_info pkt;
 669         struct sk_buff *skb;
 670         struct rxe_send_wqe *wqe;
 671         enum rxe_hdr_mask mask;
 672         u32 payload;
 673         int mtu;
 674         int opcode;
 675         int err;
 676         int ret;
 677         struct rxe_send_wqe rollback_wqe;
 678         u32 rollback_psn;
 679         struct rxe_queue *q = qp->sq.queue;
 680         struct rxe_ah *ah;
 681         struct rxe_av *av;
 682         unsigned long flags;
 683
 684         spin_lock_irqsave(&qp->state_lock, flags);
 685         if (unlikely(!qp->valid)) {
 686                 spin_unlock_irqrestore(&qp->state_lock, flags);
 687                 goto exit;
 688         }
 689
 690         if (unlikely(qp_state(qp) == IB_QPS_ERR)) {
 691                 wqe = __req_next_wqe(qp);
 692                 spin_unlock_irqrestore(&qp->state_lock, flags);
 693                 if (wqe)
 694                         goto err;
 695                 else
 696                         goto exit;
 697         }
 698
 699         if (unlikely(qp_state(qp) == IB_QPS_RESET)) {
 700                 qp->req.wqe_index = queue_get_consumer(q,
 701                                                 QUEUE_TYPE_FROM_CLIENT);
 702                 qp->req.opcode = -1;
 703                 qp->req.need_rd_atomic = 0;
 704                 qp->req.wait_psn = 0;
 705                 qp->req.need_retry = 0;
 706                 qp->req.wait_for_rnr_timer = 0;
 707                 spin_unlock_irqrestore(&qp->state_lock, flags);
 708                 goto exit;
 709         }
 710         spin_unlock_irqrestore(&qp->state_lock, flags);
 711
 712         /* we come here if the retransmit timer has fired
 713          * or if the rnr timer has fired. If the retransmit
 714          * timer fires while we are processing an RNR NAK wait
 715          * until the rnr timer has fired before starting the
 716          * retry flow
 717          */
 718         if (unlikely(qp->req.need_retry && !qp->req.wait_for_rnr_timer)) {
 719                 req_retry(qp);
 720                 qp->req.need_retry = 0;
 721         }
 722
 723         wqe = req_next_wqe(qp);
 724         if (unlikely(!wqe))
 725                 goto exit;
 726
 727         if (rxe_wqe_is_fenced(qp, wqe)) {
 728                 qp->req.wait_fence = 1;
 729                 goto exit;
 730         }
 731
 732         if (wqe->mask & WR_LOCAL_OP_MASK) {
 733                 err = rxe_do_local_ops(qp, wqe);
 734                 if (unlikely(err))
 735                         goto err;
 736                 else
 737                         goto done;
 738         }
 739
 740         if (unlikely(qp_type(qp) == IB_QPT_RC &&
 741                 psn_compare(qp->req.psn, (qp->comp.psn +
 742                                 RXE_MAX_UNACKED_PSNS)) > 0)) {
 743                 qp->req.wait_psn = 1;
 744                 goto exit;
 745         }
 746
 747         /* Limit the number of inflight SKBs per QP */
 748         if (unlikely(atomic_read(&qp->skb_out) >
 749                      RXE_INFLIGHT_SKBS_PER_QP_HIGH)) {
 750                 qp->need_req_skb = 1;
 751                 goto exit;
 752         }
 753
 754         opcode = next_opcode(qp, wqe, wqe->wr.opcode);
 755         if (unlikely(opcode < 0)) {
 756                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 757                 goto err;
 758         }
 759
 760         mask = rxe_opcode[opcode].mask;
 761         if (unlikely(mask & (RXE_READ_OR_ATOMIC_MASK |
 762                         RXE_ATOMIC_WRITE_MASK))) {
 763                 if (check_init_depth(qp, wqe))
 764                         goto exit;
 765         }
 766
 767         mtu = get_mtu(qp);
 768         payload = (mask & (RXE_WRITE_OR_SEND_MASK | RXE_ATOMIC_WRITE_MASK)) ?
 769                         wqe->dma.resid : 0;
 770         if (payload > mtu) {
 771                 if (qp_type(qp) == IB_QPT_UD) {
 772                         /* C10-93.1.1: If the total sum of all the buffer lengths specified for a
 773                          * UD message exceeds the MTU of the port as returned by QueryHCA, the CI
 774                          * shall not emit any packets for this message. Further, the CI shall not
 775                          * generate an error due to this condition.
 776                          */
 777
 778                         /* fake a successful UD send */
 779                         wqe->first_psn = qp->req.psn;
 780                         wqe->last_psn = qp->req.psn;
 781                         qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK;
 782                         qp->req.opcode = IB_OPCODE_UD_SEND_ONLY;
 783                         qp->req.wqe_index = queue_next_index(qp->sq.queue,
 784                                                        qp->req.wqe_index);
 785                         wqe->state = wqe_state_done;
 786                         wqe->status = IB_WC_SUCCESS;
 787                         rxe_sched_task(&qp->comp.task);
 788                         goto done;
 789                 }
 790                 payload = mtu;
 791         }
 792
 793         pkt.rxe = rxe;
 794         pkt.opcode = opcode;
 795         pkt.qp = qp;
 796         pkt.psn = qp->req.psn;
 797         pkt.mask = rxe_opcode[opcode].mask;
 798         pkt.wqe = wqe;
 799
 800         av = rxe_get_av(&pkt, &ah);
 801         if (unlikely(!av)) {
 802                 rxe_dbg_qp(qp, "Failed no address vector\n");
 803                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 804                 goto err;
 805         }
 806
 807         skb = init_req_packet(qp, av, wqe, opcode, payload, &pkt);
 808         if (unlikely(!skb)) {
 809                 rxe_dbg_qp(qp, "Failed allocating skb\n");
 810                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 811                 if (ah)
 812                         rxe_put(ah);
 813                 goto err;
 814         }
 815
 816         err = finish_packet(qp, av, wqe, &pkt, skb, payload);
 817         if (unlikely(err)) {
 818                 rxe_dbg_qp(qp, "Error during finish packet\n");
 819                 if (err == -EFAULT)
 820                         wqe->status = IB_WC_LOC_PROT_ERR;
 821                 else
 822                         wqe->status = IB_WC_LOC_QP_OP_ERR;
 823                 kfree_skb(skb);
 824                 if (ah)
 825                         rxe_put(ah);
 826                 goto err;
 827         }
 828
 829         if (ah)
 830                 rxe_put(ah);
 831
 832         /*
 833          * To prevent a race on wqe access between requester and completer,
 834          * wqe members state and psn need to be set before calling
 835          * rxe_xmit_packet().
 836          * Otherwise, completer might initiate an unjustified retry flow.
 837          */
 838         save_state(wqe, qp, &rollback_wqe, &rollback_psn);
 839         update_wqe_state(qp, wqe, &pkt);
 840         update_wqe_psn(qp, wqe, &pkt, payload);
 841
 842         err = rxe_xmit_packet(qp, &pkt, skb);
 843         if (err) {
 844                 qp->need_req_skb = 1;
 845
 846                 rollback_state(wqe, qp, &rollback_wqe, rollback_psn);
 847
 848                 if (err == -EAGAIN) {
 849                         rxe_sched_task(&qp->req.task);
 850                         goto exit;
 851                 }
 852
 853                 wqe->status = IB_WC_LOC_QP_OP_ERR;
 854                 goto err;
 855         }
 856
 857         update_state(qp, &pkt);
 858
 859         /* A non-zero return value will cause rxe_do_task to
 860          * exit its loop and end the tasklet. A zero return
 861          * will continue looping and return to rxe_requester
 862          */
 863 done:
 864         ret = 0;
 865         goto out;
 866 err:
 867         /* update wqe_index for each wqe completion */
 868         qp->req.wqe_index = queue_next_index(qp->sq.queue, qp->req.wqe_index);
 869         wqe->state = wqe_state_error;
 870         rxe_qp_error(qp);
 871 exit:
 872         ret = -EAGAIN;
 873 out:
 874         return ret;
 875 }