drivers/infiniband/sw/rxe/rxe_resp.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
   9 #include "rxe.h"
  10 #include "rxe_loc.h"
  11 #include "rxe_queue.h"
  12
  13 enum resp_states {
  14         RESPST_NONE,
  15         RESPST_GET_REQ,
  16         RESPST_CHK_PSN,
  17         RESPST_CHK_OP_SEQ,
  18         RESPST_CHK_OP_VALID,
  19         RESPST_CHK_RESOURCE,
  20         RESPST_CHK_LENGTH,
  21         RESPST_CHK_RKEY,
  22         RESPST_EXECUTE,
  23         RESPST_READ_REPLY,
  24         RESPST_COMPLETE,
  25         RESPST_ACKNOWLEDGE,
  26         RESPST_CLEANUP,
  27         RESPST_DUPLICATE_REQUEST,
  28         RESPST_ERR_MALFORMED_WQE,
  29         RESPST_ERR_UNSUPPORTED_OPCODE,
  30         RESPST_ERR_MISALIGNED_ATOMIC,
  31         RESPST_ERR_PSN_OUT_OF_SEQ,
  32         RESPST_ERR_MISSING_OPCODE_FIRST,
  33         RESPST_ERR_MISSING_OPCODE_LAST_C,
  34         RESPST_ERR_MISSING_OPCODE_LAST_D1E,
  35         RESPST_ERR_TOO_MANY_RDMA_ATM_REQ,
  36         RESPST_ERR_RNR,
  37         RESPST_ERR_RKEY_VIOLATION,
  38         RESPST_ERR_LENGTH,
  39         RESPST_ERR_CQ_OVERFLOW,
  40         RESPST_ERROR,
  41         RESPST_RESET,
  42         RESPST_DONE,
  43         RESPST_EXIT,
  44 };
  45
  46 static char *resp_state_name[] = {
  47         [RESPST_NONE]                           = "NONE",
  48         [RESPST_GET_REQ]                        = "GET_REQ",
  49         [RESPST_CHK_PSN]                        = "CHK_PSN",
  50         [RESPST_CHK_OP_SEQ]                     = "CHK_OP_SEQ",
  51         [RESPST_CHK_OP_VALID]                   = "CHK_OP_VALID",
  52         [RESPST_CHK_RESOURCE]                   = "CHK_RESOURCE",
  53         [RESPST_CHK_LENGTH]                     = "CHK_LENGTH",
  54         [RESPST_CHK_RKEY]                       = "CHK_RKEY",
  55         [RESPST_EXECUTE]                        = "EXECUTE",
  56         [RESPST_READ_REPLY]                     = "READ_REPLY",
  57         [RESPST_COMPLETE]                       = "COMPLETE",
  58         [RESPST_ACKNOWLEDGE]                    = "ACKNOWLEDGE",
  59         [RESPST_CLEANUP]                        = "CLEANUP",
  60         [RESPST_DUPLICATE_REQUEST]              = "DUPLICATE_REQUEST",
  61         [RESPST_ERR_MALFORMED_WQE]              = "ERR_MALFORMED_WQE",
  62         [RESPST_ERR_UNSUPPORTED_OPCODE]         = "ERR_UNSUPPORTED_OPCODE",
  63         [RESPST_ERR_MISALIGNED_ATOMIC]          = "ERR_MISALIGNED_ATOMIC",
  64         [RESPST_ERR_PSN_OUT_OF_SEQ]             = "ERR_PSN_OUT_OF_SEQ",
  65         [RESPST_ERR_MISSING_OPCODE_FIRST]       = "ERR_MISSING_OPCODE_FIRST",
  66         [RESPST_ERR_MISSING_OPCODE_LAST_C]      = "ERR_MISSING_OPCODE_LAST_C",
  67         [RESPST_ERR_MISSING_OPCODE_LAST_D1E]    = "ERR_MISSING_OPCODE_LAST_D1E",
  68         [RESPST_ERR_TOO_MANY_RDMA_ATM_REQ]      = "ERR_TOO_MANY_RDMA_ATM_REQ",
  69         [RESPST_ERR_RNR]                        = "ERR_RNR",
  70         [RESPST_ERR_RKEY_VIOLATION]             = "ERR_RKEY_VIOLATION",
  71         [RESPST_ERR_LENGTH]                     = "ERR_LENGTH",
  72         [RESPST_ERR_CQ_OVERFLOW]                = "ERR_CQ_OVERFLOW",
  73         [RESPST_ERROR]                          = "ERROR",
  74         [RESPST_RESET]                          = "RESET",
  75         [RESPST_DONE]                           = "DONE",
  76         [RESPST_EXIT]                           = "EXIT",
  77 };
  78
  79 /* rxe_recv calls here to add a request packet to the input queue */
  80 void rxe_resp_queue_pkt(struct rxe_qp *qp, struct sk_buff *skb)
  81 {
  82         int must_sched;
  83         struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
  84
  85         skb_queue_tail(&qp->req_pkts, skb);
  86
  87         must_sched = (pkt->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST) ||
  88                         (skb_queue_len(&qp->req_pkts) > 1);
  89
  90         rxe_run_task(&qp->resp.task, must_sched);
  91 }
  92
  93 static inline enum resp_states get_req(struct rxe_qp *qp,
  94                                        struct rxe_pkt_info **pkt_p)
  95 {
  96         struct sk_buff *skb;
  97
  98         if (qp->resp.state == QP_STATE_ERROR) {
  99                 while ((skb = skb_dequeue(&qp->req_pkts))) {
 100                         rxe_drop_ref(qp);
 101                         kfree_skb(skb);
 102                 }
 103
 104                 /* go drain recv wr queue */
 105                 return RESPST_CHK_RESOURCE;
 106         }
 107
 108         skb = skb_peek(&qp->req_pkts);
 109         if (!skb)
 110                 return RESPST_EXIT;
 111
 112         *pkt_p = SKB_TO_PKT(skb);
 113
 114         return (qp->resp.res) ? RESPST_READ_REPLY : RESPST_CHK_PSN;
 115 }
 116
 117 static enum resp_states check_psn(struct rxe_qp *qp,
 118                                   struct rxe_pkt_info *pkt)
 119 {
 120         int diff = psn_compare(pkt->psn, qp->resp.psn);
 121         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 122
 123         switch (qp_type(qp)) {
 124         case IB_QPT_RC:
 125                 if (diff > 0) {
 126                         if (qp->resp.sent_psn_nak)
 127                                 return RESPST_CLEANUP;
 128
 129                         qp->resp.sent_psn_nak = 1;
 130                         rxe_counter_inc(rxe, RXE_CNT_OUT_OF_SEQ_REQ);
 131                         return RESPST_ERR_PSN_OUT_OF_SEQ;
 132
 133                 } else if (diff < 0) {
 134                         rxe_counter_inc(rxe, RXE_CNT_DUP_REQ);
 135                         return RESPST_DUPLICATE_REQUEST;
 136                 }
 137
 138                 if (qp->resp.sent_psn_nak)
 139                         qp->resp.sent_psn_nak = 0;
 140
 141                 break;
 142
 143         case IB_QPT_UC:
 144                 if (qp->resp.drop_msg || diff != 0) {
 145                         if (pkt->mask & RXE_START_MASK) {
 146                                 qp->resp.drop_msg = 0;
 147                                 return RESPST_CHK_OP_SEQ;
 148                         }
 149
 150                         qp->resp.drop_msg = 1;
 151                         return RESPST_CLEANUP;
 152                 }
 153                 break;
 154         default:
 155                 break;
 156         }
 157
 158         return RESPST_CHK_OP_SEQ;
 159 }
 160
 161 static enum resp_states check_op_seq(struct rxe_qp *qp,
 162                                      struct rxe_pkt_info *pkt)
 163 {
 164         switch (qp_type(qp)) {
 165         case IB_QPT_RC:
 166                 switch (qp->resp.opcode) {
 167                 case IB_OPCODE_RC_SEND_FIRST:
 168                 case IB_OPCODE_RC_SEND_MIDDLE:
 169                         switch (pkt->opcode) {
 170                         case IB_OPCODE_RC_SEND_MIDDLE:
 171                         case IB_OPCODE_RC_SEND_LAST:
 172                         case IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE:
 173                         case IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE:
 174                                 return RESPST_CHK_OP_VALID;
 175                         default:
 176                                 return RESPST_ERR_MISSING_OPCODE_LAST_C;
 177                         }
 178
 179                 case IB_OPCODE_RC_RDMA_WRITE_FIRST:
 180                 case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
 181                         switch (pkt->opcode) {
 182                         case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
 183                         case IB_OPCODE_RC_RDMA_WRITE_LAST:
 184                         case IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 185                                 return RESPST_CHK_OP_VALID;
 186                         default:
 187                                 return RESPST_ERR_MISSING_OPCODE_LAST_C;
 188                         }
 189
 190                 default:
 191                         switch (pkt->opcode) {
 192                         case IB_OPCODE_RC_SEND_MIDDLE:
 193                         case IB_OPCODE_RC_SEND_LAST:
 194                         case IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE:
 195                         case IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE:
 196                         case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
 197                         case IB_OPCODE_RC_RDMA_WRITE_LAST:
 198                         case IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 199                                 return RESPST_ERR_MISSING_OPCODE_FIRST;
 200                         default:
 201                                 return RESPST_CHK_OP_VALID;
 202                         }
 203                 }
 204                 break;
 205
 206         case IB_QPT_UC:
 207                 switch (qp->resp.opcode) {
 208                 case IB_OPCODE_UC_SEND_FIRST:
 209                 case IB_OPCODE_UC_SEND_MIDDLE:
 210                         switch (pkt->opcode) {
 211                         case IB_OPCODE_UC_SEND_MIDDLE:
 212                         case IB_OPCODE_UC_SEND_LAST:
 213                         case IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE:
 214                                 return RESPST_CHK_OP_VALID;
 215                         default:
 216                                 return RESPST_ERR_MISSING_OPCODE_LAST_D1E;
 217                         }
 218
 219                 case IB_OPCODE_UC_RDMA_WRITE_FIRST:
 220                 case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
 221                         switch (pkt->opcode) {
 222                         case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
 223                         case IB_OPCODE_UC_RDMA_WRITE_LAST:
 224                         case IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 225                                 return RESPST_CHK_OP_VALID;
 226                         default:
 227                                 return RESPST_ERR_MISSING_OPCODE_LAST_D1E;
 228                         }
 229
 230                 default:
 231                         switch (pkt->opcode) {
 232                         case IB_OPCODE_UC_SEND_MIDDLE:
 233                         case IB_OPCODE_UC_SEND_LAST:
 234                         case IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE:
 235                         case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
 236                         case IB_OPCODE_UC_RDMA_WRITE_LAST:
 237                         case IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 238                                 qp->resp.drop_msg = 1;
 239                                 return RESPST_CLEANUP;
 240                         default:
 241                                 return RESPST_CHK_OP_VALID;
 242                         }
 243                 }
 244                 break;
 245
 246         default:
 247                 return RESPST_CHK_OP_VALID;
 248         }
 249 }
 250
 251 static enum resp_states check_op_valid(struct rxe_qp *qp,
 252                                        struct rxe_pkt_info *pkt)
 253 {
 254         switch (qp_type(qp)) {
 255         case IB_QPT_RC:
 256                 if (((pkt->mask & RXE_READ_MASK) &&
 257                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_READ)) ||
 258                     ((pkt->mask & RXE_WRITE_MASK) &&
 259                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_WRITE)) ||
 260                     ((pkt->mask & RXE_ATOMIC_MASK) &&
 261                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_ATOMIC))) {
 262                         return RESPST_ERR_UNSUPPORTED_OPCODE;
 263                 }
 264
 265                 break;
 266
 267         case IB_QPT_UC:
 268                 if ((pkt->mask & RXE_WRITE_MASK) &&
 269                     !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_WRITE)) {
 270                         qp->resp.drop_msg = 1;
 271                         return RESPST_CLEANUP;
 272                 }
 273
 274                 break;
 275
 276         case IB_QPT_UD:
 277         case IB_QPT_SMI:
 278         case IB_QPT_GSI:
 279                 break;
 280
 281         default:
 282                 WARN_ON_ONCE(1);
 283                 break;
 284         }
 285
 286         return RESPST_CHK_RESOURCE;
 287 }
 288
 289 static enum resp_states get_srq_wqe(struct rxe_qp *qp)
 290 {
 291         struct rxe_srq *srq = qp->srq;
 292         struct rxe_queue *q = srq->rq.queue;
 293         struct rxe_recv_wqe *wqe;
 294         struct ib_event ev;
 295
 296         if (srq->error)
 297                 return RESPST_ERR_RNR;
 298
 299         spin_lock_bh(&srq->rq.consumer_lock);
 300
 301         wqe = queue_head(q);
 302         if (!wqe) {
 303                 spin_unlock_bh(&srq->rq.consumer_lock);
 304                 return RESPST_ERR_RNR;
 305         }
 306
 307         /* note kernel and user space recv wqes have same size */
 308         memcpy(&qp->resp.srq_wqe, wqe, sizeof(qp->resp.srq_wqe));
 309
 310         qp->resp.wqe = &qp->resp.srq_wqe.wqe;
 311         advance_consumer(q);
 312
 313         if (srq->limit && srq->ibsrq.event_handler &&
 314             (queue_count(q) < srq->limit)) {
 315                 srq->limit = 0;
 316                 goto event;
 317         }
 318
 319         spin_unlock_bh(&srq->rq.consumer_lock);
 320         return RESPST_CHK_LENGTH;
 321
 322 event:
 323         spin_unlock_bh(&srq->rq.consumer_lock);
 324         ev.device = qp->ibqp.device;
 325         ev.element.srq = qp->ibqp.srq;
 326         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
 327         srq->ibsrq.event_handler(&ev, srq->ibsrq.srq_context);
 328         return RESPST_CHK_LENGTH;
 329 }
 330
 331 static enum resp_states check_resource(struct rxe_qp *qp,
 332                                        struct rxe_pkt_info *pkt)
 333 {
 334         struct rxe_srq *srq = qp->srq;
 335
 336         if (qp->resp.state == QP_STATE_ERROR) {
 337                 if (qp->resp.wqe) {
 338                         qp->resp.status = IB_WC_WR_FLUSH_ERR;
 339                         return RESPST_COMPLETE;
 340                 } else if (!srq) {
 341                         qp->resp.wqe = queue_head(qp->rq.queue);
 342                         if (qp->resp.wqe) {
 343                                 qp->resp.status = IB_WC_WR_FLUSH_ERR;
 344                                 return RESPST_COMPLETE;
 345                         } else {
 346                                 return RESPST_EXIT;
 347                         }
 348                 } else {
 349                         return RESPST_EXIT;
 350                 }
 351         }
 352
 353         if (pkt->mask & RXE_READ_OR_ATOMIC) {
 354                 /* it is the requesters job to not send
 355                  * too many read/atomic ops, we just
 356                  * recycle the responder resource queue
 357                  */
 358                 if (likely(qp->attr.max_dest_rd_atomic > 0))
 359                         return RESPST_CHK_LENGTH;
 360                 else
 361                         return RESPST_ERR_TOO_MANY_RDMA_ATM_REQ;
 362         }
 363
 364         if (pkt->mask & RXE_RWR_MASK) {
 365                 if (srq)
 366                         return get_srq_wqe(qp);
 367
 368                 qp->resp.wqe = queue_head(qp->rq.queue);
 369                 return (qp->resp.wqe) ? RESPST_CHK_LENGTH : RESPST_ERR_RNR;
 370         }
 371
 372         return RESPST_CHK_LENGTH;
 373 }
 374
 375 static enum resp_states check_length(struct rxe_qp *qp,
 376                                      struct rxe_pkt_info *pkt)
 377 {
 378         switch (qp_type(qp)) {
 379         case IB_QPT_RC:
 380                 return RESPST_CHK_RKEY;
 381
 382         case IB_QPT_UC:
 383                 return RESPST_CHK_RKEY;
 384
 385         default:
 386                 return RESPST_CHK_RKEY;
 387         }
 388 }
 389
 390 static enum resp_states check_rkey(struct rxe_qp *qp,
 391                                    struct rxe_pkt_info *pkt)
 392 {
 393         struct rxe_mem *mem = NULL;
 394         u64 va;
 395         u32 rkey;
 396         u32 resid;
 397         u32 pktlen;
 398         int mtu = qp->mtu;
 399         enum resp_states state;
 400         int access;
 401
 402         if (pkt->mask & (RXE_READ_MASK | RXE_WRITE_MASK)) {
 403                 if (pkt->mask & RXE_RETH_MASK) {
 404                         qp->resp.va = reth_va(pkt);
 405                         qp->resp.rkey = reth_rkey(pkt);
 406                         qp->resp.resid = reth_len(pkt);
 407                         qp->resp.length = reth_len(pkt);
 408                 }
 409                 access = (pkt->mask & RXE_READ_MASK) ? IB_ACCESS_REMOTE_READ
 410                                                      : IB_ACCESS_REMOTE_WRITE;
 411         } else if (pkt->mask & RXE_ATOMIC_MASK) {
 412                 qp->resp.va = atmeth_va(pkt);
 413                 qp->resp.rkey = atmeth_rkey(pkt);
 414                 qp->resp.resid = sizeof(u64);
 415                 access = IB_ACCESS_REMOTE_ATOMIC;
 416         } else {
 417                 return RESPST_EXECUTE;
 418         }
 419
 420         /* A zero-byte op is not required to set an addr or rkey. */
 421         if ((pkt->mask & (RXE_READ_MASK | RXE_WRITE_OR_SEND)) &&
 422             (pkt->mask & RXE_RETH_MASK) &&
 423             reth_len(pkt) == 0) {
 424                 return RESPST_EXECUTE;
 425         }
 426
 427         va      = qp->resp.va;
 428         rkey    = qp->resp.rkey;
 429         resid   = qp->resp.resid;
 430         pktlen  = payload_size(pkt);
 431
 432         mem = lookup_mem(qp->pd, access, rkey, lookup_remote);
 433         if (!mem) {
 434                 state = RESPST_ERR_RKEY_VIOLATION;
 435                 goto err;
 436         }
 437
 438         if (unlikely(mem->state == RXE_MEM_STATE_FREE)) {
 439                 state = RESPST_ERR_RKEY_VIOLATION;
 440                 goto err;
 441         }
 442
 443         if (mem_check_range(mem, va, resid)) {
 444                 state = RESPST_ERR_RKEY_VIOLATION;
 445                 goto err;
 446         }
 447
 448         if (pkt->mask & RXE_WRITE_MASK)  {
 449                 if (resid > mtu) {
 450                         if (pktlen != mtu || bth_pad(pkt)) {
 451                                 state = RESPST_ERR_LENGTH;
 452                                 goto err;
 453                         }
 454                 } else {
 455                         if (pktlen != resid) {
 456                                 state = RESPST_ERR_LENGTH;
 457                                 goto err;
 458                         }
 459                         if ((bth_pad(pkt) != (0x3 & (-resid)))) {
 460                                 /* This case may not be exactly that
 461                                  * but nothing else fits.
 462                                  */
 463                                 state = RESPST_ERR_LENGTH;
 464                                 goto err;
 465                         }
 466                 }
 467         }
 468
 469         WARN_ON_ONCE(qp->resp.mr);
 470
 471         qp->resp.mr = mem;
 472         return RESPST_EXECUTE;
 473
 474 err:
 475         if (mem)
 476                 rxe_drop_ref(mem);
 477         return state;
 478 }
 479
 480 static enum resp_states send_data_in(struct rxe_qp *qp, void *data_addr,
 481                                      int data_len)
 482 {
 483         int err;
 484
 485         err = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, &qp->resp.wqe->dma,
 486                         data_addr, data_len, to_mem_obj, NULL);
 487         if (unlikely(err))
 488                 return (err == -ENOSPC) ? RESPST_ERR_LENGTH
 489                                         : RESPST_ERR_MALFORMED_WQE;
 490
 491         return RESPST_NONE;
 492 }
 493
 494 static enum resp_states write_data_in(struct rxe_qp *qp,
 495                                       struct rxe_pkt_info *pkt)
 496 {
 497         enum resp_states rc = RESPST_NONE;
 498         int     err;
 499         int data_len = payload_size(pkt);
 500
 501         err = rxe_mem_copy(qp->resp.mr, qp->resp.va, payload_addr(pkt),
 502                            data_len, to_mem_obj, NULL);
 503         if (err) {
 504                 rc = RESPST_ERR_RKEY_VIOLATION;
 505                 goto out;
 506         }
 507
 508         qp->resp.va += data_len;
 509         qp->resp.resid -= data_len;
 510
 511 out:
 512         return rc;
 513 }
 514
 515 /* Guarantee atomicity of atomic operations at the machine level. */
 516 static DEFINE_SPINLOCK(atomic_ops_lock);
 517
 518 static enum resp_states process_atomic(struct rxe_qp *qp,
 519                                        struct rxe_pkt_info *pkt)
 520 {
 521         u64 iova = atmeth_va(pkt);
 522         u64 *vaddr;
 523         enum resp_states ret;
 524         struct rxe_mem *mr = qp->resp.mr;
 525
 526         if (mr->state != RXE_MEM_STATE_VALID) {
 527                 ret = RESPST_ERR_RKEY_VIOLATION;
 528                 goto out;
 529         }
 530
 531         vaddr = iova_to_vaddr(mr, iova, sizeof(u64));
 532
 533         /* check vaddr is 8 bytes aligned. */
 534         if (!vaddr || (uintptr_t)vaddr & 7) {
 535                 ret = RESPST_ERR_MISALIGNED_ATOMIC;
 536                 goto out;
 537         }
 538
 539         spin_lock_bh(&atomic_ops_lock);
 540
 541         qp->resp.atomic_orig = *vaddr;
 542
 543         if (pkt->opcode == IB_OPCODE_RC_COMPARE_SWAP ||
 544             pkt->opcode == IB_OPCODE_RD_COMPARE_SWAP) {
 545                 if (*vaddr == atmeth_comp(pkt))
 546                         *vaddr = atmeth_swap_add(pkt);
 547         } else {
 548                 *vaddr += atmeth_swap_add(pkt);
 549         }
 550
 551         spin_unlock_bh(&atomic_ops_lock);
 552
 553         ret = RESPST_NONE;
 554 out:
 555         return ret;
 556 }
 557
 558 static struct sk_buff *prepare_ack_packet(struct rxe_qp *qp,
 559                                           struct rxe_pkt_info *pkt,
 560                                           struct rxe_pkt_info *ack,
 561                                           int opcode,
 562                                           int payload,
 563                                           u32 psn,
 564                                           u8 syndrome,
 565                                           u32 *crcp)
 566 {
 567         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 568         struct sk_buff *skb;
 569         u32 crc = 0;
 570         u32 *p;
 571         int paylen;
 572         int pad;
 573         int err;
 574
 575         /*
 576          * allocate packet
 577          */
 578         pad = (-payload) & 0x3;
 579         paylen = rxe_opcode[opcode].length + payload + pad + RXE_ICRC_SIZE;
 580
 581         skb = rxe_init_packet(rxe, &qp->pri_av, paylen, ack);
 582         if (!skb)
 583                 return NULL;
 584
 585         ack->qp = qp;
 586         ack->opcode = opcode;
 587         ack->mask = rxe_opcode[opcode].mask;
 588         ack->offset = pkt->offset;
 589         ack->paylen = paylen;
 590
 591         /* fill in bth using the request packet headers */
 592         memcpy(ack->hdr, pkt->hdr, pkt->offset + RXE_BTH_BYTES);
 593
 594         bth_set_opcode(ack, opcode);
 595         bth_set_qpn(ack, qp->attr.dest_qp_num);
 596         bth_set_pad(ack, pad);
 597         bth_set_se(ack, 0);
 598         bth_set_psn(ack, psn);
 599         bth_set_ack(ack, 0);
 600         ack->psn = psn;
 601
 602         if (ack->mask & RXE_AETH_MASK) {
 603                 aeth_set_syn(ack, syndrome);
 604                 aeth_set_msn(ack, qp->resp.msn);
 605         }
 606
 607         if (ack->mask & RXE_ATMACK_MASK)
 608                 atmack_set_orig(ack, qp->resp.atomic_orig);
 609
 610         err = rxe_prepare(ack, skb, &crc);
 611         if (err) {
 612                 kfree_skb(skb);
 613                 return NULL;
 614         }
 615
 616         if (crcp) {
 617                 /* CRC computation will be continued by the caller */
 618                 *crcp = crc;
 619         } else {
 620                 p = payload_addr(ack) + payload + bth_pad(ack);
 621                 *p = ~crc;
 622         }
 623
 624         return skb;
 625 }
 626
 627 /* RDMA read response. If res is not NULL, then we have a current RDMA request
 628  * being processed or replayed.
 629  */
 630 static enum resp_states read_reply(struct rxe_qp *qp,
 631                                    struct rxe_pkt_info *req_pkt)
 632 {
 633         struct rxe_pkt_info ack_pkt;
 634         struct sk_buff *skb;
 635         int mtu = qp->mtu;
 636         enum resp_states state;
 637         int payload;
 638         int opcode;
 639         int err;
 640         struct resp_res *res = qp->resp.res;
 641         u32 icrc;
 642         u32 *p;
 643
 644         if (!res) {
 645                 /* This is the first time we process that request. Get a
 646                  * resource
 647                  */
 648                 res = &qp->resp.resources[qp->resp.res_head];
 649
 650                 free_rd_atomic_resource(qp, res);
 651                 rxe_advance_resp_resource(qp);
 652
 653                 res->type               = RXE_READ_MASK;
 654                 res->replay             = 0;
 655
 656                 res->read.va            = qp->resp.va;
 657                 res->read.va_org        = qp->resp.va;
 658
 659                 res->first_psn          = req_pkt->psn;
 660
 661                 if (reth_len(req_pkt)) {
 662                         res->last_psn   = (req_pkt->psn +
 663                                            (reth_len(req_pkt) + mtu - 1) /
 664                                            mtu - 1) & BTH_PSN_MASK;
 665                 } else {
 666                         res->last_psn   = res->first_psn;
 667                 }
 668                 res->cur_psn            = req_pkt->psn;
 669
 670                 res->read.resid         = qp->resp.resid;
 671                 res->read.length        = qp->resp.resid;
 672                 res->read.rkey          = qp->resp.rkey;
 673
 674                 /* note res inherits the reference to mr from qp */
 675                 res->read.mr            = qp->resp.mr;
 676                 qp->resp.mr             = NULL;
 677
 678                 qp->resp.res            = res;
 679                 res->state              = rdatm_res_state_new;
 680         }
 681
 682         if (res->state == rdatm_res_state_new) {
 683                 if (res->read.resid <= mtu)
 684                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY;
 685                 else
 686                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST;
 687         } else {
 688                 if (res->read.resid > mtu)
 689                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE;
 690                 else
 691                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST;
 692         }
 693
 694         res->state = rdatm_res_state_next;
 695
 696         payload = min_t(int, res->read.resid, mtu);
 697
 698         skb = prepare_ack_packet(qp, req_pkt, &ack_pkt, opcode, payload,
 699                                  res->cur_psn, AETH_ACK_UNLIMITED, &icrc);
 700         if (!skb)
 701                 return RESPST_ERR_RNR;
 702
 703         err = rxe_mem_copy(res->read.mr, res->read.va, payload_addr(&ack_pkt),
 704                            payload, from_mem_obj, &icrc);
 705         if (err)
 706                 pr_err("Failed copying memory\n");
 707
 708         if (bth_pad(&ack_pkt)) {
 709                 struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 710                 u8 *pad = payload_addr(&ack_pkt) + payload;
 711
 712                 memset(pad, 0, bth_pad(&ack_pkt));
 713                 icrc = rxe_crc32(rxe, icrc, pad, bth_pad(&ack_pkt));
 714         }
 715         p = payload_addr(&ack_pkt) + payload + bth_pad(&ack_pkt);
 716         *p = ~icrc;
 717
 718         err = rxe_xmit_packet(qp, &ack_pkt, skb);
 719         if (err) {
 720                 pr_err("Failed sending RDMA reply.\n");
 721                 return RESPST_ERR_RNR;
 722         }
 723
 724         res->read.va += payload;
 725         res->read.resid -= payload;
 726         res->cur_psn = (res->cur_psn + 1) & BTH_PSN_MASK;
 727
 728         if (res->read.resid > 0) {
 729                 state = RESPST_DONE;
 730         } else {
 731                 qp->resp.res = NULL;
 732                 if (!res->replay)
 733                         qp->resp.opcode = -1;
 734                 if (psn_compare(res->cur_psn, qp->resp.psn) >= 0)
 735                         qp->resp.psn = res->cur_psn;
 736                 state = RESPST_CLEANUP;
 737         }
 738
 739         return state;
 740 }
 741
 742 static void build_rdma_network_hdr(union rdma_network_hdr *hdr,
 743                                    struct rxe_pkt_info *pkt)
 744 {
 745         struct sk_buff *skb = PKT_TO_SKB(pkt);
 746
 747         memset(hdr, 0, sizeof(*hdr));
 748         if (skb->protocol == htons(ETH_P_IP))
 749                 memcpy(&hdr->roce4grh, ip_hdr(skb), sizeof(hdr->roce4grh));
 750         else if (skb->protocol == htons(ETH_P_IPV6))
 751                 memcpy(&hdr->ibgrh, ipv6_hdr(skb), sizeof(hdr->ibgrh));
 752 }
 753
 754 /* Executes a new request. A retried request never reach that function (send
 755  * and writes are discarded, and reads and atomics are retried elsewhere.
 756  */
 757 static enum resp_states execute(struct rxe_qp *qp, struct rxe_pkt_info *pkt)
 758 {
 759         enum resp_states err;
 760
 761         if (pkt->mask & RXE_SEND_MASK) {
 762                 if (qp_type(qp) == IB_QPT_UD ||
 763                     qp_type(qp) == IB_QPT_SMI ||
 764                     qp_type(qp) == IB_QPT_GSI) {
 765                         union rdma_network_hdr hdr;
 766
 767                         build_rdma_network_hdr(&hdr, pkt);
 768
 769                         err = send_data_in(qp, &hdr, sizeof(hdr));
 770                         if (err)
 771                                 return err;
 772                 }
 773                 err = send_data_in(qp, payload_addr(pkt), payload_size(pkt));
 774                 if (err)
 775                         return err;
 776         } else if (pkt->mask & RXE_WRITE_MASK) {
 777                 err = write_data_in(qp, pkt);
 778                 if (err)
 779                         return err;
 780         } else if (pkt->mask & RXE_READ_MASK) {
 781                 /* For RDMA Read we can increment the msn now. See C9-148. */
 782                 qp->resp.msn++;
 783                 return RESPST_READ_REPLY;
 784         } else if (pkt->mask & RXE_ATOMIC_MASK) {
 785                 err = process_atomic(qp, pkt);
 786                 if (err)
 787                         return err;
 788         } else {
 789                 /* Unreachable */
 790                 WARN_ON_ONCE(1);
 791         }
 792
 793         /* next expected psn, read handles this separately */
 794         qp->resp.psn = (pkt->psn + 1) & BTH_PSN_MASK;
 795         qp->resp.ack_psn = qp->resp.psn;
 796
 797         qp->resp.opcode = pkt->opcode;
 798         qp->resp.status = IB_WC_SUCCESS;
 799
 800         if (pkt->mask & RXE_COMP_MASK) {
 801                 /* We successfully processed this new request. */
 802                 qp->resp.msn++;
 803                 return RESPST_COMPLETE;
 804         } else if (qp_type(qp) == IB_QPT_RC)
 805                 return RESPST_ACKNOWLEDGE;
 806         else
 807                 return RESPST_CLEANUP;
 808 }
 809
 810 static enum resp_states do_complete(struct rxe_qp *qp,
 811                                     struct rxe_pkt_info *pkt)
 812 {
 813         struct rxe_cqe cqe;
 814         struct ib_wc *wc = &cqe.ibwc;
 815         struct ib_uverbs_wc *uwc = &cqe.uibwc;
 816         struct rxe_recv_wqe *wqe = qp->resp.wqe;
 817         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 818
 819         if (unlikely(!wqe))
 820                 return RESPST_CLEANUP;
 821
 822         memset(&cqe, 0, sizeof(cqe));
 823
 824         if (qp->rcq->is_user) {
 825                 uwc->status             = qp->resp.status;
 826                 uwc->qp_num             = qp->ibqp.qp_num;
 827                 uwc->wr_id              = wqe->wr_id;
 828         } else {
 829                 wc->status              = qp->resp.status;
 830                 wc->qp                  = &qp->ibqp;
 831                 wc->wr_id               = wqe->wr_id;
 832         }
 833
 834         if (wc->status == IB_WC_SUCCESS) {
 835                 rxe_counter_inc(rxe, RXE_CNT_RDMA_RECV);
 836                 wc->opcode = (pkt->mask & RXE_IMMDT_MASK &&
 837                                 pkt->mask & RXE_WRITE_MASK) ?
 838                                         IB_WC_RECV_RDMA_WITH_IMM : IB_WC_RECV;
 839                 wc->vendor_err = 0;
 840                 wc->byte_len = (pkt->mask & RXE_IMMDT_MASK &&
 841                                 pkt->mask & RXE_WRITE_MASK) ?
 842                                         qp->resp.length : wqe->dma.length - wqe->dma.resid;
 843
 844                 /* fields after byte_len are different between kernel and user
 845                  * space
 846                  */
 847                 if (qp->rcq->is_user) {
 848                         uwc->wc_flags = IB_WC_GRH;
 849
 850                         if (pkt->mask & RXE_IMMDT_MASK) {
 851                                 uwc->wc_flags |= IB_WC_WITH_IMM;
 852                                 uwc->ex.imm_data = immdt_imm(pkt);
 853                         }
 854
 855                         if (pkt->mask & RXE_IETH_MASK) {
 856                                 uwc->wc_flags |= IB_WC_WITH_INVALIDATE;
 857                                 uwc->ex.invalidate_rkey = ieth_rkey(pkt);
 858                         }
 859
 860                         uwc->qp_num             = qp->ibqp.qp_num;
 861
 862                         if (pkt->mask & RXE_DETH_MASK)
 863                                 uwc->src_qp = deth_sqp(pkt);
 864
 865                         uwc->port_num           = qp->attr.port_num;
 866                 } else {
 867                         struct sk_buff *skb = PKT_TO_SKB(pkt);
 868
 869                         wc->wc_flags = IB_WC_GRH | IB_WC_WITH_NETWORK_HDR_TYPE;
 870                         if (skb->protocol == htons(ETH_P_IP))
 871                                 wc->network_hdr_type = RDMA_NETWORK_IPV4;
 872                         else
 873                                 wc->network_hdr_type = RDMA_NETWORK_IPV6;
 874
 875                         if (pkt->mask & RXE_IMMDT_MASK) {
 876                                 wc->wc_flags |= IB_WC_WITH_IMM;
 877                                 wc->ex.imm_data = immdt_imm(pkt);
 878                         }
 879
 880                         if (pkt->mask & RXE_IETH_MASK) {
 881                                 struct rxe_mem *rmr;
 882
 883                                 wc->wc_flags |= IB_WC_WITH_INVALIDATE;
 884                                 wc->ex.invalidate_rkey = ieth_rkey(pkt);
 885
 886                                 rmr = rxe_pool_get_index(&rxe->mr_pool,
 887                                                          wc->ex.invalidate_rkey >> 8);
 888                                 if (unlikely(!rmr)) {
 889                                         pr_err("Bad rkey %#x invalidation\n",
 890                                                wc->ex.invalidate_rkey);
 891                                         return RESPST_ERROR;
 892                                 }
 893                                 rmr->state = RXE_MEM_STATE_FREE;
 894                                 rxe_drop_ref(rmr);
 895                         }
 896
 897                         wc->qp                  = &qp->ibqp;
 898
 899                         if (pkt->mask & RXE_DETH_MASK)
 900                                 wc->src_qp = deth_sqp(pkt);
 901
 902                         wc->port_num            = qp->attr.port_num;
 903                 }
 904         }
 905
 906         /* have copy for srq and reference for !srq */
 907         if (!qp->srq)
 908                 advance_consumer(qp->rq.queue);
 909
 910         qp->resp.wqe = NULL;
 911
 912         if (rxe_cq_post(qp->rcq, &cqe, pkt ? bth_se(pkt) : 1))
 913                 return RESPST_ERR_CQ_OVERFLOW;
 914
 915         if (qp->resp.state == QP_STATE_ERROR)
 916                 return RESPST_CHK_RESOURCE;
 917
 918         if (!pkt)
 919                 return RESPST_DONE;
 920         else if (qp_type(qp) == IB_QPT_RC)
 921                 return RESPST_ACKNOWLEDGE;
 922         else
 923                 return RESPST_CLEANUP;
 924 }
 925
 926 static int send_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
 927                     u8 syndrome, u32 psn)
 928 {
 929         int err = 0;
 930         struct rxe_pkt_info ack_pkt;
 931         struct sk_buff *skb;
 932
 933         skb = prepare_ack_packet(qp, pkt, &ack_pkt, IB_OPCODE_RC_ACKNOWLEDGE,
 934                                  0, psn, syndrome, NULL);
 935         if (!skb) {
 936                 err = -ENOMEM;
 937                 goto err1;
 938         }
 939
 940         err = rxe_xmit_packet(qp, &ack_pkt, skb);
 941         if (err)
 942                 pr_err_ratelimited("Failed sending ack\n");
 943
 944 err1:
 945         return err;
 946 }
 947
 948 static int send_atomic_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
 949                            u8 syndrome)
 950 {
 951         int rc = 0;
 952         struct rxe_pkt_info ack_pkt;
 953         struct sk_buff *skb;
 954         struct resp_res *res;
 955
 956         skb = prepare_ack_packet(qp, pkt, &ack_pkt,
 957                                  IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE, 0, pkt->psn,
 958                                  syndrome, NULL);
 959         if (!skb) {
 960                 rc = -ENOMEM;
 961                 goto out;
 962         }
 963
 964         rxe_add_ref(qp);
 965
 966         res = &qp->resp.resources[qp->resp.res_head];
 967         free_rd_atomic_resource(qp, res);
 968         rxe_advance_resp_resource(qp);
 969
 970         memcpy(SKB_TO_PKT(skb), &ack_pkt, sizeof(ack_pkt));
 971         memset((unsigned char *)SKB_TO_PKT(skb) + sizeof(ack_pkt), 0,
 972                sizeof(skb->cb) - sizeof(ack_pkt));
 973
 974         skb_get(skb);
 975         res->type = RXE_ATOMIC_MASK;
 976         res->atomic.skb = skb;
 977         res->first_psn = ack_pkt.psn;
 978         res->last_psn  = ack_pkt.psn;
 979         res->cur_psn   = ack_pkt.psn;
 980
 981         rc = rxe_xmit_packet(qp, &ack_pkt, skb);
 982         if (rc) {
 983                 pr_err_ratelimited("Failed sending ack\n");
 984                 rxe_drop_ref(qp);
 985         }
 986 out:
 987         return rc;
 988 }
 989
 990 static enum resp_states acknowledge(struct rxe_qp *qp,
 991                                     struct rxe_pkt_info *pkt)
 992 {
 993         if (qp_type(qp) != IB_QPT_RC)
 994                 return RESPST_CLEANUP;
 995
 996         if (qp->resp.aeth_syndrome != AETH_ACK_UNLIMITED)
 997                 send_ack(qp, pkt, qp->resp.aeth_syndrome, pkt->psn);
 998         else if (pkt->mask & RXE_ATOMIC_MASK)
 999                 send_atomic_ack(qp, pkt, AETH_ACK_UNLIMITED);
1000         else if (bth_ack(pkt))
1001                 send_ack(qp, pkt, AETH_ACK_UNLIMITED, pkt->psn);
1002
1003         return RESPST_CLEANUP;
1004 }
1005
1006 static enum resp_states cleanup(struct rxe_qp *qp,
1007                                 struct rxe_pkt_info *pkt)
1008 {
1009         struct sk_buff *skb;
1010
1011         if (pkt) {
1012                 skb = skb_dequeue(&qp->req_pkts);
1013                 rxe_drop_ref(qp);
1014                 kfree_skb(skb);
1015         }
1016
1017         if (qp->resp.mr) {
1018                 rxe_drop_ref(qp->resp.mr);
1019                 qp->resp.mr = NULL;
1020         }
1021
1022         return RESPST_DONE;
1023 }
1024
1025 static struct resp_res *find_resource(struct rxe_qp *qp, u32 psn)
1026 {
1027         int i;
1028
1029         for (i = 0; i < qp->attr.max_dest_rd_atomic; i++) {
1030                 struct resp_res *res = &qp->resp.resources[i];
1031
1032                 if (res->type == 0)
1033                         continue;
1034
1035                 if (psn_compare(psn, res->first_psn) >= 0 &&
1036                     psn_compare(psn, res->last_psn) <= 0) {
1037                         return res;
1038                 }
1039         }
1040
1041         return NULL;
1042 }
1043
1044 static enum resp_states duplicate_request(struct rxe_qp *qp,
1045                                           struct rxe_pkt_info *pkt)
1046 {
1047         enum resp_states rc;
1048         u32 prev_psn = (qp->resp.ack_psn - 1) & BTH_PSN_MASK;
1049
1050         if (pkt->mask & RXE_SEND_MASK ||
1051             pkt->mask & RXE_WRITE_MASK) {
1052                 /* SEND. Ack again and cleanup. C9-105. */
1053                 if (bth_ack(pkt))
1054                         send_ack(qp, pkt, AETH_ACK_UNLIMITED, prev_psn);
1055                 rc = RESPST_CLEANUP;
1056                 goto out;
1057         } else if (pkt->mask & RXE_READ_MASK) {
1058                 struct resp_res *res;
1059
1060                 res = find_resource(qp, pkt->psn);
1061                 if (!res) {
1062                         /* Resource not found. Class D error.  Drop the
1063                          * request.
1064                          */
1065                         rc = RESPST_CLEANUP;
1066                         goto out;
1067                 } else {
1068                         /* Ensure this new request is the same as the previous
1069                          * one or a subset of it.
1070                          */
1071                         u64 iova = reth_va(pkt);
1072                         u32 resid = reth_len(pkt);
1073
1074                         if (iova < res->read.va_org ||
1075                             resid > res->read.length ||
1076                             (iova + resid) > (res->read.va_org +
1077                                               res->read.length)) {
1078                                 rc = RESPST_CLEANUP;
1079                                 goto out;
1080                         }
1081
1082                         if (reth_rkey(pkt) != res->read.rkey) {
1083                                 rc = RESPST_CLEANUP;
1084                                 goto out;
1085                         }
1086
1087                         res->cur_psn = pkt->psn;
1088                         res->state = (pkt->psn == res->first_psn) ?
1089                                         rdatm_res_state_new :
1090                                         rdatm_res_state_replay;
1091                         res->replay = 1;
1092
1093                         /* Reset the resource, except length. */
1094                         res->read.va_org = iova;
1095                         res->read.va = iova;
1096                         res->read.resid = resid;
1097
1098                         /* Replay the RDMA read reply. */
1099                         qp->resp.res = res;
1100                         rc = RESPST_READ_REPLY;
1101                         goto out;
1102                 }
1103         } else {
1104                 struct resp_res *res;
1105
1106                 /* Find the operation in our list of responder resources. */
1107                 res = find_resource(qp, pkt->psn);
1108                 if (res) {
1109                         skb_get(res->atomic.skb);
1110                         /* Resend the result. */
1111                         rc = rxe_xmit_packet(qp, pkt, res->atomic.skb);
1112                         if (rc) {
1113                                 pr_err("Failed resending result. This flow is not handled - skb ignored\n");
1114                                 rc = RESPST_CLEANUP;
1115                                 goto out;
1116                         }
1117                 }
1118
1119                 /* Resource not found. Class D error. Drop the request. */
1120                 rc = RESPST_CLEANUP;
1121                 goto out;
1122         }
1123 out:
1124         return rc;
1125 }
1126
1127 /* Process a class A or C. Both are treated the same in this implementation. */
1128 static void do_class_ac_error(struct rxe_qp *qp, u8 syndrome,
1129                               enum ib_wc_status status)
1130 {
1131         qp->resp.aeth_syndrome  = syndrome;
1132         qp->resp.status         = status;
1133
1134         /* indicate that we should go through the ERROR state */
1135         qp->resp.goto_error     = 1;
1136 }
1137
1138 static enum resp_states do_class_d1e_error(struct rxe_qp *qp)
1139 {
1140         /* UC */
1141         if (qp->srq) {
1142                 /* Class E */
1143                 qp->resp.drop_msg = 1;
1144                 if (qp->resp.wqe) {
1145                         qp->resp.status = IB_WC_REM_INV_REQ_ERR;
1146                         return RESPST_COMPLETE;
1147                 } else {
1148                         return RESPST_CLEANUP;
1149                 }
1150         } else {
1151                 /* Class D1. This packet may be the start of a
1152                  * new message and could be valid. The previous
1153                  * message is invalid and ignored. reset the
1154                  * recv wr to its original state
1155                  */
1156                 if (qp->resp.wqe) {
1157                         qp->resp.wqe->dma.resid = qp->resp.wqe->dma.length;
1158                         qp->resp.wqe->dma.cur_sge = 0;
1159                         qp->resp.wqe->dma.sge_offset = 0;
1160                         qp->resp.opcode = -1;
1161                 }
1162
1163                 if (qp->resp.mr) {
1164                         rxe_drop_ref(qp->resp.mr);
1165                         qp->resp.mr = NULL;
1166                 }
1167
1168                 return RESPST_CLEANUP;
1169         }
1170 }
1171
1172 static void rxe_drain_req_pkts(struct rxe_qp *qp, bool notify)
1173 {
1174         struct sk_buff *skb;
1175
1176         while ((skb = skb_dequeue(&qp->req_pkts))) {
1177                 rxe_drop_ref(qp);
1178                 kfree_skb(skb);
1179         }
1180
1181         if (notify)
1182                 return;
1183
1184         while (!qp->srq && qp->rq.queue && queue_head(qp->rq.queue))
1185                 advance_consumer(qp->rq.queue);
1186 }
1187
1188 int rxe_responder(void *arg)
1189 {
1190         struct rxe_qp *qp = (struct rxe_qp *)arg;
1191         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
1192         enum resp_states state;
1193         struct rxe_pkt_info *pkt = NULL;
1194         int ret = 0;
1195
1196         rxe_add_ref(qp);
1197
1198         qp->resp.aeth_syndrome = AETH_ACK_UNLIMITED;
1199
1200         if (!qp->valid) {
1201                 ret = -EINVAL;
1202                 goto done;
1203         }
1204
1205         switch (qp->resp.state) {
1206         case QP_STATE_RESET:
1207                 state = RESPST_RESET;
1208                 break;
1209
1210         default:
1211                 state = RESPST_GET_REQ;
1212                 break;
1213         }
1214
1215         while (1) {
1216                 pr_debug("qp#%d state = %s\n", qp_num(qp),
1217                          resp_state_name[state]);
1218                 switch (state) {
1219                 case RESPST_GET_REQ:
1220                         state = get_req(qp, &pkt);
1221                         break;
1222                 case RESPST_CHK_PSN:
1223                         state = check_psn(qp, pkt);
1224                         break;
1225                 case RESPST_CHK_OP_SEQ:
1226                         state = check_op_seq(qp, pkt);
1227                         break;
1228                 case RESPST_CHK_OP_VALID:
1229                         state = check_op_valid(qp, pkt);
1230                         break;
1231                 case RESPST_CHK_RESOURCE:
1232                         state = check_resource(qp, pkt);
1233                         break;
1234                 case RESPST_CHK_LENGTH:
1235                         state = check_length(qp, pkt);
1236                         break;
1237                 case RESPST_CHK_RKEY:
1238                         state = check_rkey(qp, pkt);
1239                         break;
1240                 case RESPST_EXECUTE:
1241                         state = execute(qp, pkt);
1242                         break;
1243                 case RESPST_COMPLETE:
1244                         state = do_complete(qp, pkt);
1245                         break;
1246                 case RESPST_READ_REPLY:
1247                         state = read_reply(qp, pkt);
1248                         break;
1249                 case RESPST_ACKNOWLEDGE:
1250                         state = acknowledge(qp, pkt);
1251                         break;
1252                 case RESPST_CLEANUP:
1253                         state = cleanup(qp, pkt);
1254                         break;
1255                 case RESPST_DUPLICATE_REQUEST:
1256                         state = duplicate_request(qp, pkt);
1257                         break;
1258                 case RESPST_ERR_PSN_OUT_OF_SEQ:
1259                         /* RC only - Class B. Drop packet. */
1260                         send_ack(qp, pkt, AETH_NAK_PSN_SEQ_ERROR, qp->resp.psn);
1261                         state = RESPST_CLEANUP;
1262                         break;
1263
1264                 case RESPST_ERR_TOO_MANY_RDMA_ATM_REQ:
1265                 case RESPST_ERR_MISSING_OPCODE_FIRST:
1266                 case RESPST_ERR_MISSING_OPCODE_LAST_C:
1267                 case RESPST_ERR_UNSUPPORTED_OPCODE:
1268                 case RESPST_ERR_MISALIGNED_ATOMIC:
1269                         /* RC Only - Class C. */
1270                         do_class_ac_error(qp, AETH_NAK_INVALID_REQ,
1271                                           IB_WC_REM_INV_REQ_ERR);
1272                         state = RESPST_COMPLETE;
1273                         break;
1274
1275                 case RESPST_ERR_MISSING_OPCODE_LAST_D1E:
1276                         state = do_class_d1e_error(qp);
1277                         break;
1278                 case RESPST_ERR_RNR:
1279                         if (qp_type(qp) == IB_QPT_RC) {
1280                                 rxe_counter_inc(rxe, RXE_CNT_SND_RNR);
1281                                 /* RC - class B */
1282                                 send_ack(qp, pkt, AETH_RNR_NAK |
1283                                          (~AETH_TYPE_MASK &
1284                                          qp->attr.min_rnr_timer),
1285                                          pkt->psn);
1286                         } else {
1287                                 /* UD/UC - class D */
1288                                 qp->resp.drop_msg = 1;
1289                         }
1290                         state = RESPST_CLEANUP;
1291                         break;
1292
1293                 case RESPST_ERR_RKEY_VIOLATION:
1294                         if (qp_type(qp) == IB_QPT_RC) {
1295                                 /* Class C */
1296                                 do_class_ac_error(qp, AETH_NAK_REM_ACC_ERR,
1297                                                   IB_WC_REM_ACCESS_ERR);
1298                                 state = RESPST_COMPLETE;
1299                         } else {
1300                                 qp->resp.drop_msg = 1;
1301                                 if (qp->srq) {
1302                                         /* UC/SRQ Class D */
1303                                         qp->resp.status = IB_WC_REM_ACCESS_ERR;
1304                                         state = RESPST_COMPLETE;
1305                                 } else {
1306                                         /* UC/non-SRQ Class E. */
1307                                         state = RESPST_CLEANUP;
1308                                 }
1309                         }
1310                         break;
1311
1312                 case RESPST_ERR_LENGTH:
1313                         if (qp_type(qp) == IB_QPT_RC) {
1314                                 /* Class C */
1315                                 do_class_ac_error(qp, AETH_NAK_INVALID_REQ,
1316                                                   IB_WC_REM_INV_REQ_ERR);
1317                                 state = RESPST_COMPLETE;
1318                         } else if (qp->srq) {
1319                                 /* UC/UD - class E */
1320                                 qp->resp.status = IB_WC_REM_INV_REQ_ERR;
1321                                 state = RESPST_COMPLETE;
1322                         } else {
1323                                 /* UC/UD - class D */
1324                                 qp->resp.drop_msg = 1;
1325                                 state = RESPST_CLEANUP;
1326                         }
1327                         break;
1328
1329                 case RESPST_ERR_MALFORMED_WQE:
1330                         /* All, Class A. */
1331                         do_class_ac_error(qp, AETH_NAK_REM_OP_ERR,
1332                                           IB_WC_LOC_QP_OP_ERR);
1333                         state = RESPST_COMPLETE;
1334                         break;
1335
1336                 case RESPST_ERR_CQ_OVERFLOW:
1337                         /* All - Class G */
1338                         state = RESPST_ERROR;
1339                         break;
1340
1341                 case RESPST_DONE:
1342                         if (qp->resp.goto_error) {
1343                                 state = RESPST_ERROR;
1344                                 break;
1345                         }
1346
1347                         goto done;
1348
1349                 case RESPST_EXIT:
1350                         if (qp->resp.goto_error) {
1351                                 state = RESPST_ERROR;
1352                                 break;
1353                         }
1354
1355                         goto exit;
1356
1357                 case RESPST_RESET:
1358                         rxe_drain_req_pkts(qp, false);
1359                         qp->resp.wqe = NULL;
1360                         goto exit;
1361
1362                 case RESPST_ERROR:
1363                         qp->resp.goto_error = 0;
1364                         pr_warn("qp#%d moved to error state\n", qp_num(qp));
1365                         rxe_qp_error(qp);
1366                         goto exit;
1367
1368                 default:
1369                         WARN_ON_ONCE(1);
1370                 }
1371         }
1372
1373 exit:
1374         ret = -EAGAIN;
1375 done:
1376         rxe_drop_ref(qp);
1377         return ret;
1378 }