drivers/infiniband/sw/rxe/rxe_resp.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 enum resp_states {
  41         RESPST_NONE,
  42         RESPST_GET_REQ,
  43         RESPST_CHK_PSN,
  44         RESPST_CHK_OP_SEQ,
  45         RESPST_CHK_OP_VALID,
  46         RESPST_CHK_RESOURCE,
  47         RESPST_CHK_LENGTH,
  48         RESPST_CHK_RKEY,
  49         RESPST_EXECUTE,
  50         RESPST_READ_REPLY,
  51         RESPST_COMPLETE,
  52         RESPST_ACKNOWLEDGE,
  53         RESPST_CLEANUP,
  54         RESPST_DUPLICATE_REQUEST,
  55         RESPST_ERR_MALFORMED_WQE,
  56         RESPST_ERR_UNSUPPORTED_OPCODE,
  57         RESPST_ERR_MISALIGNED_ATOMIC,
  58         RESPST_ERR_PSN_OUT_OF_SEQ,
  59         RESPST_ERR_MISSING_OPCODE_FIRST,
  60         RESPST_ERR_MISSING_OPCODE_LAST_C,
  61         RESPST_ERR_MISSING_OPCODE_LAST_D1E,
  62         RESPST_ERR_TOO_MANY_RDMA_ATM_REQ,
  63         RESPST_ERR_RNR,
  64         RESPST_ERR_RKEY_VIOLATION,
  65         RESPST_ERR_LENGTH,
  66         RESPST_ERR_CQ_OVERFLOW,
  67         RESPST_ERROR,
  68         RESPST_RESET,
  69         RESPST_DONE,
  70         RESPST_EXIT,
  71 };
  72
  73 static char *resp_state_name[] = {
  74         [RESPST_NONE]                           = "NONE",
  75         [RESPST_GET_REQ]                        = "GET_REQ",
  76         [RESPST_CHK_PSN]                        = "CHK_PSN",
  77         [RESPST_CHK_OP_SEQ]                     = "CHK_OP_SEQ",
  78         [RESPST_CHK_OP_VALID]                   = "CHK_OP_VALID",
  79         [RESPST_CHK_RESOURCE]                   = "CHK_RESOURCE",
  80         [RESPST_CHK_LENGTH]                     = "CHK_LENGTH",
  81         [RESPST_CHK_RKEY]                       = "CHK_RKEY",
  82         [RESPST_EXECUTE]                        = "EXECUTE",
  83         [RESPST_READ_REPLY]                     = "READ_REPLY",
  84         [RESPST_COMPLETE]                       = "COMPLETE",
  85         [RESPST_ACKNOWLEDGE]                    = "ACKNOWLEDGE",
  86         [RESPST_CLEANUP]                        = "CLEANUP",
  87         [RESPST_DUPLICATE_REQUEST]              = "DUPLICATE_REQUEST",
  88         [RESPST_ERR_MALFORMED_WQE]              = "ERR_MALFORMED_WQE",
  89         [RESPST_ERR_UNSUPPORTED_OPCODE]         = "ERR_UNSUPPORTED_OPCODE",
  90         [RESPST_ERR_MISALIGNED_ATOMIC]          = "ERR_MISALIGNED_ATOMIC",
  91         [RESPST_ERR_PSN_OUT_OF_SEQ]             = "ERR_PSN_OUT_OF_SEQ",
  92         [RESPST_ERR_MISSING_OPCODE_FIRST]       = "ERR_MISSING_OPCODE_FIRST",
  93         [RESPST_ERR_MISSING_OPCODE_LAST_C]      = "ERR_MISSING_OPCODE_LAST_C",
  94         [RESPST_ERR_MISSING_OPCODE_LAST_D1E]    = "ERR_MISSING_OPCODE_LAST_D1E",
  95         [RESPST_ERR_TOO_MANY_RDMA_ATM_REQ]      = "ERR_TOO_MANY_RDMA_ATM_REQ",
  96         [RESPST_ERR_RNR]                        = "ERR_RNR",
  97         [RESPST_ERR_RKEY_VIOLATION]             = "ERR_RKEY_VIOLATION",
  98         [RESPST_ERR_LENGTH]                     = "ERR_LENGTH",
  99         [RESPST_ERR_CQ_OVERFLOW]                = "ERR_CQ_OVERFLOW",
 100         [RESPST_ERROR]                          = "ERROR",
 101         [RESPST_RESET]                          = "RESET",
 102         [RESPST_DONE]                           = "DONE",
 103         [RESPST_EXIT]                           = "EXIT",
 104 };
 105
 106 /* rxe_recv calls here to add a request packet to the input queue */
 107 void rxe_resp_queue_pkt(struct rxe_dev *rxe, struct rxe_qp *qp,
 108                         struct sk_buff *skb)
 109 {
 110         int must_sched;
 111         struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
 112
 113         skb_queue_tail(&qp->req_pkts, skb);
 114
 115         must_sched = (pkt->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST) ||
 116                         (skb_queue_len(&qp->req_pkts) > 1);
 117
 118         rxe_run_task(&qp->resp.task, must_sched);
 119 }
 120
 121 static inline enum resp_states get_req(struct rxe_qp *qp,
 122                                        struct rxe_pkt_info **pkt_p)
 123 {
 124         struct sk_buff *skb;
 125
 126         if (qp->resp.state == QP_STATE_ERROR) {
 127                 skb = skb_dequeue(&qp->req_pkts);
 128                 if (skb) {
 129                         /* drain request packet queue */
 130                         rxe_drop_ref(qp);
 131                         kfree_skb(skb);
 132                         return RESPST_GET_REQ;
 133                 }
 134
 135                 /* go drain recv wr queue */
 136                 return RESPST_CHK_RESOURCE;
 137         }
 138
 139         skb = skb_peek(&qp->req_pkts);
 140         if (!skb)
 141                 return RESPST_EXIT;
 142
 143         *pkt_p = SKB_TO_PKT(skb);
 144
 145         return (qp->resp.res) ? RESPST_READ_REPLY : RESPST_CHK_PSN;
 146 }
 147
 148 static enum resp_states check_psn(struct rxe_qp *qp,
 149                                   struct rxe_pkt_info *pkt)
 150 {
 151         int diff = psn_compare(pkt->psn, qp->resp.psn);
 152
 153         switch (qp_type(qp)) {
 154         case IB_QPT_RC:
 155                 if (diff > 0) {
 156                         if (qp->resp.sent_psn_nak)
 157                                 return RESPST_CLEANUP;
 158
 159                         qp->resp.sent_psn_nak = 1;
 160                         return RESPST_ERR_PSN_OUT_OF_SEQ;
 161
 162                 } else if (diff < 0) {
 163                         return RESPST_DUPLICATE_REQUEST;
 164                 }
 165
 166                 if (qp->resp.sent_psn_nak)
 167                         qp->resp.sent_psn_nak = 0;
 168
 169                 break;
 170
 171         case IB_QPT_UC:
 172                 if (qp->resp.drop_msg || diff != 0) {
 173                         if (pkt->mask & RXE_START_MASK) {
 174                                 qp->resp.drop_msg = 0;
 175                                 return RESPST_CHK_OP_SEQ;
 176                         }
 177
 178                         qp->resp.drop_msg = 1;
 179                         return RESPST_CLEANUP;
 180                 }
 181                 break;
 182         default:
 183                 break;
 184         }
 185
 186         return RESPST_CHK_OP_SEQ;
 187 }
 188
 189 static enum resp_states check_op_seq(struct rxe_qp *qp,
 190                                      struct rxe_pkt_info *pkt)
 191 {
 192         switch (qp_type(qp)) {
 193         case IB_QPT_RC:
 194                 switch (qp->resp.opcode) {
 195                 case IB_OPCODE_RC_SEND_FIRST:
 196                 case IB_OPCODE_RC_SEND_MIDDLE:
 197                         switch (pkt->opcode) {
 198                         case IB_OPCODE_RC_SEND_MIDDLE:
 199                         case IB_OPCODE_RC_SEND_LAST:
 200                         case IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE:
 201                         case IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE:
 202                                 return RESPST_CHK_OP_VALID;
 203                         default:
 204                                 return RESPST_ERR_MISSING_OPCODE_LAST_C;
 205                         }
 206
 207                 case IB_OPCODE_RC_RDMA_WRITE_FIRST:
 208                 case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
 209                         switch (pkt->opcode) {
 210                         case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
 211                         case IB_OPCODE_RC_RDMA_WRITE_LAST:
 212                         case IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 213                                 return RESPST_CHK_OP_VALID;
 214                         default:
 215                                 return RESPST_ERR_MISSING_OPCODE_LAST_C;
 216                         }
 217
 218                 default:
 219                         switch (pkt->opcode) {
 220                         case IB_OPCODE_RC_SEND_MIDDLE:
 221                         case IB_OPCODE_RC_SEND_LAST:
 222                         case IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE:
 223                         case IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE:
 224                         case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
 225                         case IB_OPCODE_RC_RDMA_WRITE_LAST:
 226                         case IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 227                                 return RESPST_ERR_MISSING_OPCODE_FIRST;
 228                         default:
 229                                 return RESPST_CHK_OP_VALID;
 230                         }
 231                 }
 232                 break;
 233
 234         case IB_QPT_UC:
 235                 switch (qp->resp.opcode) {
 236                 case IB_OPCODE_UC_SEND_FIRST:
 237                 case IB_OPCODE_UC_SEND_MIDDLE:
 238                         switch (pkt->opcode) {
 239                         case IB_OPCODE_UC_SEND_MIDDLE:
 240                         case IB_OPCODE_UC_SEND_LAST:
 241                         case IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE:
 242                                 return RESPST_CHK_OP_VALID;
 243                         default:
 244                                 return RESPST_ERR_MISSING_OPCODE_LAST_D1E;
 245                         }
 246
 247                 case IB_OPCODE_UC_RDMA_WRITE_FIRST:
 248                 case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
 249                         switch (pkt->opcode) {
 250                         case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
 251                         case IB_OPCODE_UC_RDMA_WRITE_LAST:
 252                         case IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 253                                 return RESPST_CHK_OP_VALID;
 254                         default:
 255                                 return RESPST_ERR_MISSING_OPCODE_LAST_D1E;
 256                         }
 257
 258                 default:
 259                         switch (pkt->opcode) {
 260                         case IB_OPCODE_UC_SEND_MIDDLE:
 261                         case IB_OPCODE_UC_SEND_LAST:
 262                         case IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE:
 263                         case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
 264                         case IB_OPCODE_UC_RDMA_WRITE_LAST:
 265                         case IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
 266                                 qp->resp.drop_msg = 1;
 267                                 return RESPST_CLEANUP;
 268                         default:
 269                                 return RESPST_CHK_OP_VALID;
 270                         }
 271                 }
 272                 break;
 273
 274         default:
 275                 return RESPST_CHK_OP_VALID;
 276         }
 277 }
 278
 279 static enum resp_states check_op_valid(struct rxe_qp *qp,
 280                                        struct rxe_pkt_info *pkt)
 281 {
 282         switch (qp_type(qp)) {
 283         case IB_QPT_RC:
 284                 if (((pkt->mask & RXE_READ_MASK) &&
 285                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_READ)) ||
 286                     ((pkt->mask & RXE_WRITE_MASK) &&
 287                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_WRITE)) ||
 288                     ((pkt->mask & RXE_ATOMIC_MASK) &&
 289                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_ATOMIC))) {
 290                         return RESPST_ERR_UNSUPPORTED_OPCODE;
 291                 }
 292
 293                 break;
 294
 295         case IB_QPT_UC:
 296                 if ((pkt->mask & RXE_WRITE_MASK) &&
 297                     !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_WRITE)) {
 298                         qp->resp.drop_msg = 1;
 299                         return RESPST_CLEANUP;
 300                 }
 301
 302                 break;
 303
 304         case IB_QPT_UD:
 305         case IB_QPT_SMI:
 306         case IB_QPT_GSI:
 307                 break;
 308
 309         default:
 310                 WARN_ON(1);
 311                 break;
 312         }
 313
 314         return RESPST_CHK_RESOURCE;
 315 }
 316
 317 static enum resp_states get_srq_wqe(struct rxe_qp *qp)
 318 {
 319         struct rxe_srq *srq = qp->srq;
 320         struct rxe_queue *q = srq->rq.queue;
 321         struct rxe_recv_wqe *wqe;
 322         struct ib_event ev;
 323
 324         if (srq->error)
 325                 return RESPST_ERR_RNR;
 326
 327         spin_lock_bh(&srq->rq.consumer_lock);
 328
 329         wqe = queue_head(q);
 330         if (!wqe) {
 331                 spin_unlock_bh(&srq->rq.consumer_lock);
 332                 return RESPST_ERR_RNR;
 333         }
 334
 335         /* note kernel and user space recv wqes have same size */
 336         memcpy(&qp->resp.srq_wqe, wqe, sizeof(qp->resp.srq_wqe));
 337
 338         qp->resp.wqe = &qp->resp.srq_wqe.wqe;
 339         advance_consumer(q);
 340
 341         if (srq->limit && srq->ibsrq.event_handler &&
 342             (queue_count(q) < srq->limit)) {
 343                 srq->limit = 0;
 344                 goto event;
 345         }
 346
 347         spin_unlock_bh(&srq->rq.consumer_lock);
 348         return RESPST_CHK_LENGTH;
 349
 350 event:
 351         spin_unlock_bh(&srq->rq.consumer_lock);
 352         ev.device = qp->ibqp.device;
 353         ev.element.srq = qp->ibqp.srq;
 354         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
 355         srq->ibsrq.event_handler(&ev, srq->ibsrq.srq_context);
 356         return RESPST_CHK_LENGTH;
 357 }
 358
 359 static enum resp_states check_resource(struct rxe_qp *qp,
 360                                        struct rxe_pkt_info *pkt)
 361 {
 362         struct rxe_srq *srq = qp->srq;
 363
 364         if (qp->resp.state == QP_STATE_ERROR) {
 365                 if (qp->resp.wqe) {
 366                         qp->resp.status = IB_WC_WR_FLUSH_ERR;
 367                         return RESPST_COMPLETE;
 368                 } else if (!srq) {
 369                         qp->resp.wqe = queue_head(qp->rq.queue);
 370                         if (qp->resp.wqe) {
 371                                 qp->resp.status = IB_WC_WR_FLUSH_ERR;
 372                                 return RESPST_COMPLETE;
 373                         } else {
 374                                 return RESPST_EXIT;
 375                         }
 376                 } else {
 377                         return RESPST_EXIT;
 378                 }
 379         }
 380
 381         if (pkt->mask & RXE_READ_OR_ATOMIC) {
 382                 /* it is the requesters job to not send
 383                  * too many read/atomic ops, we just
 384                  * recycle the responder resource queue
 385                  */
 386                 if (likely(qp->attr.max_rd_atomic > 0))
 387                         return RESPST_CHK_LENGTH;
 388                 else
 389                         return RESPST_ERR_TOO_MANY_RDMA_ATM_REQ;
 390         }
 391
 392         if (pkt->mask & RXE_RWR_MASK) {
 393                 if (srq)
 394                         return get_srq_wqe(qp);
 395
 396                 qp->resp.wqe = queue_head(qp->rq.queue);
 397                 return (qp->resp.wqe) ? RESPST_CHK_LENGTH : RESPST_ERR_RNR;
 398         }
 399
 400         return RESPST_CHK_LENGTH;
 401 }
 402
 403 static enum resp_states check_length(struct rxe_qp *qp,
 404                                      struct rxe_pkt_info *pkt)
 405 {
 406         switch (qp_type(qp)) {
 407         case IB_QPT_RC:
 408                 return RESPST_CHK_RKEY;
 409
 410         case IB_QPT_UC:
 411                 return RESPST_CHK_RKEY;
 412
 413         default:
 414                 return RESPST_CHK_RKEY;
 415         }
 416 }
 417
 418 static enum resp_states check_rkey(struct rxe_qp *qp,
 419                                    struct rxe_pkt_info *pkt)
 420 {
 421         struct rxe_mem *mem;
 422         u64 va;
 423         u32 rkey;
 424         u32 resid;
 425         u32 pktlen;
 426         int mtu = qp->mtu;
 427         enum resp_states state;
 428         int access;
 429
 430         if (pkt->mask & (RXE_READ_MASK | RXE_WRITE_MASK)) {
 431                 if (pkt->mask & RXE_RETH_MASK) {
 432                         qp->resp.va = reth_va(pkt);
 433                         qp->resp.rkey = reth_rkey(pkt);
 434                         qp->resp.resid = reth_len(pkt);
 435                 }
 436                 access = (pkt->mask & RXE_READ_MASK) ? IB_ACCESS_REMOTE_READ
 437                                                      : IB_ACCESS_REMOTE_WRITE;
 438         } else if (pkt->mask & RXE_ATOMIC_MASK) {
 439                 qp->resp.va = atmeth_va(pkt);
 440                 qp->resp.rkey = atmeth_rkey(pkt);
 441                 qp->resp.resid = sizeof(u64);
 442                 access = IB_ACCESS_REMOTE_ATOMIC;
 443         } else {
 444                 return RESPST_EXECUTE;
 445         }
 446
 447         va      = qp->resp.va;
 448         rkey    = qp->resp.rkey;
 449         resid   = qp->resp.resid;
 450         pktlen  = payload_size(pkt);
 451
 452         mem = lookup_mem(qp->pd, access, rkey, lookup_remote);
 453         if (!mem) {
 454                 state = RESPST_ERR_RKEY_VIOLATION;
 455                 goto err1;
 456         }
 457
 458         if (unlikely(mem->state == RXE_MEM_STATE_FREE)) {
 459                 state = RESPST_ERR_RKEY_VIOLATION;
 460                 goto err1;
 461         }
 462
 463         if (mem_check_range(mem, va, resid)) {
 464                 state = RESPST_ERR_RKEY_VIOLATION;
 465                 goto err2;
 466         }
 467
 468         if (pkt->mask & RXE_WRITE_MASK)  {
 469                 if (resid > mtu) {
 470                         if (pktlen != mtu || bth_pad(pkt)) {
 471                                 state = RESPST_ERR_LENGTH;
 472                                 goto err2;
 473                         }
 474
 475                         resid = mtu;
 476                 } else {
 477                         if (pktlen != resid) {
 478                                 state = RESPST_ERR_LENGTH;
 479                                 goto err2;
 480                         }
 481                         if ((bth_pad(pkt) != (0x3 & (-resid)))) {
 482                                 /* This case may not be exactly that
 483                                  * but nothing else fits.
 484                                  */
 485                                 state = RESPST_ERR_LENGTH;
 486                                 goto err2;
 487                         }
 488                 }
 489         }
 490
 491         WARN_ON(qp->resp.mr);
 492
 493         qp->resp.mr = mem;
 494         return RESPST_EXECUTE;
 495
 496 err2:
 497         rxe_drop_ref(mem);
 498 err1:
 499         return state;
 500 }
 501
 502 static enum resp_states send_data_in(struct rxe_qp *qp, void *data_addr,
 503                                      int data_len)
 504 {
 505         int err;
 506         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 507
 508         err = copy_data(rxe, qp->pd, IB_ACCESS_LOCAL_WRITE, &qp->resp.wqe->dma,
 509                         data_addr, data_len, to_mem_obj, NULL);
 510         if (unlikely(err))
 511                 return (err == -ENOSPC) ? RESPST_ERR_LENGTH
 512                                         : RESPST_ERR_MALFORMED_WQE;
 513
 514         return RESPST_NONE;
 515 }
 516
 517 static enum resp_states write_data_in(struct rxe_qp *qp,
 518                                       struct rxe_pkt_info *pkt)
 519 {
 520         enum resp_states rc = RESPST_NONE;
 521         int     err;
 522         int data_len = payload_size(pkt);
 523
 524         err = rxe_mem_copy(qp->resp.mr, qp->resp.va, payload_addr(pkt),
 525                            data_len, to_mem_obj, NULL);
 526         if (err) {
 527                 rc = RESPST_ERR_RKEY_VIOLATION;
 528                 goto out;
 529         }
 530
 531         qp->resp.va += data_len;
 532         qp->resp.resid -= data_len;
 533
 534 out:
 535         return rc;
 536 }
 537
 538 /* Guarantee atomicity of atomic operations at the machine level. */
 539 static DEFINE_SPINLOCK(atomic_ops_lock);
 540
 541 static enum resp_states process_atomic(struct rxe_qp *qp,
 542                                        struct rxe_pkt_info *pkt)
 543 {
 544         u64 iova = atmeth_va(pkt);
 545         u64 *vaddr;
 546         enum resp_states ret;
 547         struct rxe_mem *mr = qp->resp.mr;
 548
 549         if (mr->state != RXE_MEM_STATE_VALID) {
 550                 ret = RESPST_ERR_RKEY_VIOLATION;
 551                 goto out;
 552         }
 553
 554         vaddr = iova_to_vaddr(mr, iova, sizeof(u64));
 555
 556         /* check vaddr is 8 bytes aligned. */
 557         if (!vaddr || (uintptr_t)vaddr & 7) {
 558                 ret = RESPST_ERR_MISALIGNED_ATOMIC;
 559                 goto out;
 560         }
 561
 562         spin_lock_bh(&atomic_ops_lock);
 563
 564         qp->resp.atomic_orig = *vaddr;
 565
 566         if (pkt->opcode == IB_OPCODE_RC_COMPARE_SWAP ||
 567             pkt->opcode == IB_OPCODE_RD_COMPARE_SWAP) {
 568                 if (*vaddr == atmeth_comp(pkt))
 569                         *vaddr = atmeth_swap_add(pkt);
 570         } else {
 571                 *vaddr += atmeth_swap_add(pkt);
 572         }
 573
 574         spin_unlock_bh(&atomic_ops_lock);
 575
 576         ret = RESPST_NONE;
 577 out:
 578         return ret;
 579 }
 580
 581 static struct sk_buff *prepare_ack_packet(struct rxe_qp *qp,
 582                                           struct rxe_pkt_info *pkt,
 583                                           struct rxe_pkt_info *ack,
 584                                           int opcode,
 585                                           int payload,
 586                                           u32 psn,
 587                                           u8 syndrome,
 588                                           u32 *crcp)
 589 {
 590         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 591         struct sk_buff *skb;
 592         u32 crc = 0;
 593         u32 *p;
 594         int paylen;
 595         int pad;
 596         int err;
 597
 598         /*
 599          * allocate packet
 600          */
 601         pad = (-payload) & 0x3;
 602         paylen = rxe_opcode[opcode].length + payload + pad + RXE_ICRC_SIZE;
 603
 604         skb = rxe->ifc_ops->init_packet(rxe, &qp->pri_av, paylen, ack);
 605         if (!skb)
 606                 return NULL;
 607
 608         ack->qp = qp;
 609         ack->opcode = opcode;
 610         ack->mask = rxe_opcode[opcode].mask;
 611         ack->offset = pkt->offset;
 612         ack->paylen = paylen;
 613
 614         /* fill in bth using the request packet headers */
 615         memcpy(ack->hdr, pkt->hdr, pkt->offset + RXE_BTH_BYTES);
 616
 617         bth_set_opcode(ack, opcode);
 618         bth_set_qpn(ack, qp->attr.dest_qp_num);
 619         bth_set_pad(ack, pad);
 620         bth_set_se(ack, 0);
 621         bth_set_psn(ack, psn);
 622         bth_set_ack(ack, 0);
 623         ack->psn = psn;
 624
 625         if (ack->mask & RXE_AETH_MASK) {
 626                 aeth_set_syn(ack, syndrome);
 627                 aeth_set_msn(ack, qp->resp.msn);
 628         }
 629
 630         if (ack->mask & RXE_ATMACK_MASK)
 631                 atmack_set_orig(ack, qp->resp.atomic_orig);
 632
 633         err = rxe->ifc_ops->prepare(rxe, ack, skb, &crc);
 634         if (err) {
 635                 kfree_skb(skb);
 636                 return NULL;
 637         }
 638
 639         if (crcp) {
 640                 /* CRC computation will be continued by the caller */
 641                 *crcp = crc;
 642         } else {
 643                 p = payload_addr(ack) + payload + bth_pad(ack);
 644                 *p = ~crc;
 645         }
 646
 647         return skb;
 648 }
 649
 650 /* RDMA read response. If res is not NULL, then we have a current RDMA request
 651  * being processed or replayed.
 652  */
 653 static enum resp_states read_reply(struct rxe_qp *qp,
 654                                    struct rxe_pkt_info *req_pkt)
 655 {
 656         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 657         struct rxe_pkt_info ack_pkt;
 658         struct sk_buff *skb;
 659         int mtu = qp->mtu;
 660         enum resp_states state;
 661         int payload;
 662         int opcode;
 663         int err;
 664         struct resp_res *res = qp->resp.res;
 665         u32 icrc;
 666         u32 *p;
 667
 668         if (!res) {
 669                 /* This is the first time we process that request. Get a
 670                  * resource
 671                  */
 672                 res = &qp->resp.resources[qp->resp.res_head];
 673
 674                 free_rd_atomic_resource(qp, res);
 675                 rxe_advance_resp_resource(qp);
 676
 677                 res->type               = RXE_READ_MASK;
 678
 679                 res->read.va            = qp->resp.va;
 680                 res->read.va_org        = qp->resp.va;
 681
 682                 res->first_psn          = req_pkt->psn;
 683                 res->last_psn           = req_pkt->psn +
 684                                           (reth_len(req_pkt) + mtu - 1) /
 685                                           mtu - 1;
 686                 res->cur_psn            = req_pkt->psn;
 687
 688                 res->read.resid         = qp->resp.resid;
 689                 res->read.length        = qp->resp.resid;
 690                 res->read.rkey          = qp->resp.rkey;
 691
 692                 /* note res inherits the reference to mr from qp */
 693                 res->read.mr            = qp->resp.mr;
 694                 qp->resp.mr             = NULL;
 695
 696                 qp->resp.res            = res;
 697                 res->state              = rdatm_res_state_new;
 698         }
 699
 700         if (res->state == rdatm_res_state_new) {
 701                 if (res->read.resid <= mtu)
 702                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY;
 703                 else
 704                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST;
 705         } else {
 706                 if (res->read.resid > mtu)
 707                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE;
 708                 else
 709                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST;
 710         }
 711
 712         res->state = rdatm_res_state_next;
 713
 714         payload = min_t(int, res->read.resid, mtu);
 715
 716         skb = prepare_ack_packet(qp, req_pkt, &ack_pkt, opcode, payload,
 717                                  res->cur_psn, AETH_ACK_UNLIMITED, &icrc);
 718         if (!skb)
 719                 return RESPST_ERR_RNR;
 720
 721         err = rxe_mem_copy(res->read.mr, res->read.va, payload_addr(&ack_pkt),
 722                            payload, from_mem_obj, &icrc);
 723         if (err)
 724                 pr_err("Failed copying memory\n");
 725
 726         p = payload_addr(&ack_pkt) + payload + bth_pad(&ack_pkt);
 727         *p = ~icrc;
 728
 729         err = rxe_xmit_packet(rxe, qp, &ack_pkt, skb);
 730         if (err) {
 731                 pr_err("Failed sending RDMA reply.\n");
 732                 kfree_skb(skb);
 733                 return RESPST_ERR_RNR;
 734         }
 735
 736         res->read.va += payload;
 737         res->read.resid -= payload;
 738         res->cur_psn = (res->cur_psn + 1) & BTH_PSN_MASK;
 739
 740         if (res->read.resid > 0) {
 741                 state = RESPST_DONE;
 742         } else {
 743                 qp->resp.res = NULL;
 744                 qp->resp.opcode = -1;
 745                 qp->resp.psn = res->cur_psn;
 746                 state = RESPST_CLEANUP;
 747         }
 748
 749         return state;
 750 }
 751
 752 /* Executes a new request. A retried request never reach that function (send
 753  * and writes are discarded, and reads and atomics are retried elsewhere.
 754  */
 755 static enum resp_states execute(struct rxe_qp *qp, struct rxe_pkt_info *pkt)
 756 {
 757         enum resp_states err;
 758
 759         if (pkt->mask & RXE_SEND_MASK) {
 760                 if (qp_type(qp) == IB_QPT_UD ||
 761                     qp_type(qp) == IB_QPT_SMI ||
 762                     qp_type(qp) == IB_QPT_GSI) {
 763                         union rdma_network_hdr hdr;
 764                         struct sk_buff *skb = PKT_TO_SKB(pkt);
 765
 766                         memset(&hdr, 0, sizeof(hdr));
 767                         if (skb->protocol == htons(ETH_P_IP))
 768                                 memcpy(&hdr.roce4grh, ip_hdr(skb), sizeof(hdr.roce4grh));
 769                         else if (skb->protocol == htons(ETH_P_IPV6))
 770                                 memcpy(&hdr.ibgrh, ipv6_hdr(skb), sizeof(hdr.ibgrh));
 771
 772                         err = send_data_in(qp, &hdr, sizeof(hdr));
 773                         if (err)
 774                                 return err;
 775                 }
 776                 err = send_data_in(qp, payload_addr(pkt), payload_size(pkt));
 777                 if (err)
 778                         return err;
 779         } else if (pkt->mask & RXE_WRITE_MASK) {
 780                 err = write_data_in(qp, pkt);
 781                 if (err)
 782                         return err;
 783         } else if (pkt->mask & RXE_READ_MASK) {
 784                 /* For RDMA Read we can increment the msn now. See C9-148. */
 785                 qp->resp.msn++;
 786                 return RESPST_READ_REPLY;
 787         } else if (pkt->mask & RXE_ATOMIC_MASK) {
 788                 err = process_atomic(qp, pkt);
 789                 if (err)
 790                         return err;
 791         } else
 792                 /* Unreachable */
 793                 WARN_ON(1);
 794
 795         /* We successfully processed this new request. */
 796         qp->resp.msn++;
 797
 798         /* next expected psn, read handles this separately */
 799         qp->resp.psn = (pkt->psn + 1) & BTH_PSN_MASK;
 800
 801         qp->resp.opcode = pkt->opcode;
 802         qp->resp.status = IB_WC_SUCCESS;
 803
 804         if (pkt->mask & RXE_COMP_MASK)
 805                 return RESPST_COMPLETE;
 806         else if (qp_type(qp) == IB_QPT_RC)
 807                 return RESPST_ACKNOWLEDGE;
 808         else
 809                 return RESPST_CLEANUP;
 810 }
 811
 812 static enum resp_states do_complete(struct rxe_qp *qp,
 813                                     struct rxe_pkt_info *pkt)
 814 {
 815         struct rxe_cqe cqe;
 816         struct ib_wc *wc = &cqe.ibwc;
 817         struct ib_uverbs_wc *uwc = &cqe.uibwc;
 818         struct rxe_recv_wqe *wqe = qp->resp.wqe;
 819
 820         if (unlikely(!wqe))
 821                 return RESPST_CLEANUP;
 822
 823         memset(&cqe, 0, sizeof(cqe));
 824
 825         wc->wr_id               = wqe->wr_id;
 826         wc->status              = qp->resp.status;
 827         wc->qp                  = &qp->ibqp;
 828
 829         /* fields after status are not required for errors */
 830         if (wc->status == IB_WC_SUCCESS) {
 831                 wc->opcode = (pkt->mask & RXE_IMMDT_MASK &&
 832                                 pkt->mask & RXE_WRITE_MASK) ?
 833                                         IB_WC_RECV_RDMA_WITH_IMM : IB_WC_RECV;
 834                 wc->vendor_err = 0;
 835                 wc->byte_len = wqe->dma.length - wqe->dma.resid;
 836
 837                 /* fields after byte_len are different between kernel and user
 838                  * space
 839                  */
 840                 if (qp->rcq->is_user) {
 841                         uwc->wc_flags = IB_WC_GRH;
 842
 843                         if (pkt->mask & RXE_IMMDT_MASK) {
 844                                 uwc->wc_flags |= IB_WC_WITH_IMM;
 845                                 uwc->ex.imm_data =
 846                                         (__u32 __force)immdt_imm(pkt);
 847                         }
 848
 849                         if (pkt->mask & RXE_IETH_MASK) {
 850                                 uwc->wc_flags |= IB_WC_WITH_INVALIDATE;
 851                                 uwc->ex.invalidate_rkey = ieth_rkey(pkt);
 852                         }
 853
 854                         uwc->qp_num             = qp->ibqp.qp_num;
 855
 856                         if (pkt->mask & RXE_DETH_MASK)
 857                                 uwc->src_qp = deth_sqp(pkt);
 858
 859                         uwc->port_num           = qp->attr.port_num;
 860                 } else {
 861                         struct sk_buff *skb = PKT_TO_SKB(pkt);
 862
 863                         wc->wc_flags = IB_WC_GRH | IB_WC_WITH_NETWORK_HDR_TYPE;
 864                         if (skb->protocol == htons(ETH_P_IP))
 865                                 wc->network_hdr_type = RDMA_NETWORK_IPV4;
 866                         else
 867                                 wc->network_hdr_type = RDMA_NETWORK_IPV6;
 868
 869                         if (pkt->mask & RXE_IMMDT_MASK) {
 870                                 wc->wc_flags |= IB_WC_WITH_IMM;
 871                                 wc->ex.imm_data = immdt_imm(pkt);
 872                         }
 873
 874                         if (pkt->mask & RXE_IETH_MASK) {
 875                                 struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 876                                 struct rxe_mem *rmr;
 877
 878                                 wc->wc_flags |= IB_WC_WITH_INVALIDATE;
 879                                 wc->ex.invalidate_rkey = ieth_rkey(pkt);
 880
 881                                 rmr = rxe_pool_get_index(&rxe->mr_pool,
 882                                                          wc->ex.invalidate_rkey >> 8);
 883                                 if (unlikely(!rmr)) {
 884                                         pr_err("Bad rkey %#x invalidation\n", wc->ex.invalidate_rkey);
 885                                         return RESPST_ERROR;
 886                                 }
 887                                 rmr->state = RXE_MEM_STATE_FREE;
 888                         }
 889
 890                         wc->qp                  = &qp->ibqp;
 891
 892                         if (pkt->mask & RXE_DETH_MASK)
 893                                 wc->src_qp = deth_sqp(pkt);
 894
 895                         wc->port_num            = qp->attr.port_num;
 896                 }
 897         }
 898
 899         /* have copy for srq and reference for !srq */
 900         if (!qp->srq)
 901                 advance_consumer(qp->rq.queue);
 902
 903         qp->resp.wqe = NULL;
 904
 905         if (rxe_cq_post(qp->rcq, &cqe, pkt ? bth_se(pkt) : 1))
 906                 return RESPST_ERR_CQ_OVERFLOW;
 907
 908         if (qp->resp.state == QP_STATE_ERROR)
 909                 return RESPST_CHK_RESOURCE;
 910
 911         if (!pkt)
 912                 return RESPST_DONE;
 913         else if (qp_type(qp) == IB_QPT_RC)
 914                 return RESPST_ACKNOWLEDGE;
 915         else
 916                 return RESPST_CLEANUP;
 917 }
 918
 919 static int send_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
 920                     u8 syndrome, u32 psn)
 921 {
 922         int err = 0;
 923         struct rxe_pkt_info ack_pkt;
 924         struct sk_buff *skb;
 925         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 926
 927         skb = prepare_ack_packet(qp, pkt, &ack_pkt, IB_OPCODE_RC_ACKNOWLEDGE,
 928                                  0, psn, syndrome, NULL);
 929         if (!skb) {
 930                 err = -ENOMEM;
 931                 goto err1;
 932         }
 933
 934         err = rxe_xmit_packet(rxe, qp, &ack_pkt, skb);
 935         if (err) {
 936                 pr_err_ratelimited("Failed sending ack\n");
 937                 kfree_skb(skb);
 938         }
 939
 940 err1:
 941         return err;
 942 }
 943
 944 static int send_atomic_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
 945                            u8 syndrome)
 946 {
 947         int rc = 0;
 948         struct rxe_pkt_info ack_pkt;
 949         struct sk_buff *skb;
 950         struct sk_buff *skb_copy;
 951         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 952         struct resp_res *res;
 953
 954         skb = prepare_ack_packet(qp, pkt, &ack_pkt,
 955                                  IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE, 0, pkt->psn,
 956                                  syndrome, NULL);
 957         if (!skb) {
 958                 rc = -ENOMEM;
 959                 goto out;
 960         }
 961
 962         skb_copy = skb_clone(skb, GFP_ATOMIC);
 963         if (skb_copy)
 964                 rxe_add_ref(qp); /* for the new SKB */
 965         else {
 966                 pr_warn("Could not clone atomic response\n");
 967                 rc = -ENOMEM;
 968                 goto out;
 969         }
 970
 971         res = &qp->resp.resources[qp->resp.res_head];
 972         free_rd_atomic_resource(qp, res);
 973         rxe_advance_resp_resource(qp);
 974
 975         memcpy(SKB_TO_PKT(skb), &ack_pkt, sizeof(skb->cb));
 976
 977         res->type = RXE_ATOMIC_MASK;
 978         res->atomic.skb = skb;
 979         res->first_psn = ack_pkt.psn;
 980         res->last_psn  = ack_pkt.psn;
 981         res->cur_psn   = ack_pkt.psn;
 982
 983         rc = rxe_xmit_packet(rxe, qp, &ack_pkt, skb_copy);
 984         if (rc) {
 985                 pr_err_ratelimited("Failed sending ack\n");
 986                 rxe_drop_ref(qp);
 987                 kfree_skb(skb_copy);
 988         }
 989
 990 out:
 991         return rc;
 992 }
 993
 994 static enum resp_states acknowledge(struct rxe_qp *qp,
 995                                     struct rxe_pkt_info *pkt)
 996 {
 997         if (qp_type(qp) != IB_QPT_RC)
 998                 return RESPST_CLEANUP;
 999
1000         if (qp->resp.aeth_syndrome != AETH_ACK_UNLIMITED)
1001                 send_ack(qp, pkt, qp->resp.aeth_syndrome, pkt->psn);
1002         else if (pkt->mask & RXE_ATOMIC_MASK)
1003                 send_atomic_ack(qp, pkt, AETH_ACK_UNLIMITED);
1004         else if (bth_ack(pkt))
1005                 send_ack(qp, pkt, AETH_ACK_UNLIMITED, pkt->psn);
1006
1007         return RESPST_CLEANUP;
1008 }
1009
1010 static enum resp_states cleanup(struct rxe_qp *qp,
1011                                 struct rxe_pkt_info *pkt)
1012 {
1013         struct sk_buff *skb;
1014
1015         if (pkt) {
1016                 skb = skb_dequeue(&qp->req_pkts);
1017                 rxe_drop_ref(qp);
1018                 kfree_skb(skb);
1019         }
1020
1021         if (qp->resp.mr) {
1022                 rxe_drop_ref(qp->resp.mr);
1023                 qp->resp.mr = NULL;
1024         }
1025
1026         return RESPST_DONE;
1027 }
1028
1029 static struct resp_res *find_resource(struct rxe_qp *qp, u32 psn)
1030 {
1031         int i;
1032
1033         for (i = 0; i < qp->attr.max_rd_atomic; i++) {
1034                 struct resp_res *res = &qp->resp.resources[i];
1035
1036                 if (res->type == 0)
1037                         continue;
1038
1039                 if (psn_compare(psn, res->first_psn) >= 0 &&
1040                     psn_compare(psn, res->last_psn) <= 0) {
1041                         return res;
1042                 }
1043         }
1044
1045         return NULL;
1046 }
1047
1048 static enum resp_states duplicate_request(struct rxe_qp *qp,
1049                                           struct rxe_pkt_info *pkt)
1050 {
1051         enum resp_states rc;
1052
1053         if (pkt->mask & RXE_SEND_MASK ||
1054             pkt->mask & RXE_WRITE_MASK) {
1055                 /* SEND. Ack again and cleanup. C9-105. */
1056                 if (bth_ack(pkt))
1057                         send_ack(qp, pkt, AETH_ACK_UNLIMITED, qp->resp.psn - 1);
1058                 rc = RESPST_CLEANUP;
1059                 goto out;
1060         } else if (pkt->mask & RXE_READ_MASK) {
1061                 struct resp_res *res;
1062
1063                 res = find_resource(qp, pkt->psn);
1064                 if (!res) {
1065                         /* Resource not found. Class D error.  Drop the
1066                          * request.
1067                          */
1068                         rc = RESPST_CLEANUP;
1069                         goto out;
1070                 } else {
1071                         /* Ensure this new request is the same as the previous
1072                          * one or a subset of it.
1073                          */
1074                         u64 iova = reth_va(pkt);
1075                         u32 resid = reth_len(pkt);
1076
1077                         if (iova < res->read.va_org ||
1078                             resid > res->read.length ||
1079                             (iova + resid) > (res->read.va_org +
1080                                               res->read.length)) {
1081                                 rc = RESPST_CLEANUP;
1082                                 goto out;
1083                         }
1084
1085                         if (reth_rkey(pkt) != res->read.rkey) {
1086                                 rc = RESPST_CLEANUP;
1087                                 goto out;
1088                         }
1089
1090                         res->cur_psn = pkt->psn;
1091                         res->state = (pkt->psn == res->first_psn) ?
1092                                         rdatm_res_state_new :
1093                                         rdatm_res_state_replay;
1094
1095                         /* Reset the resource, except length. */
1096                         res->read.va_org = iova;
1097                         res->read.va = iova;
1098                         res->read.resid = resid;
1099
1100                         /* Replay the RDMA read reply. */
1101                         qp->resp.res = res;
1102                         rc = RESPST_READ_REPLY;
1103                         goto out;
1104                 }
1105         } else {
1106                 struct resp_res *res;
1107
1108                 /* Find the operation in our list of responder resources. */
1109                 res = find_resource(qp, pkt->psn);
1110                 if (res) {
1111                         struct sk_buff *skb_copy;
1112
1113                         skb_copy = skb_clone(res->atomic.skb, GFP_ATOMIC);
1114                         if (skb_copy) {
1115                                 rxe_add_ref(qp); /* for the new SKB */
1116                         } else {
1117                                 pr_warn("Couldn't clone atomic resp\n");
1118                                 rc = RESPST_CLEANUP;
1119                                 goto out;
1120                         }
1121
1122                         /* Resend the result. */
1123                         rc = rxe_xmit_packet(to_rdev(qp->ibqp.device), qp,
1124                                              pkt, skb_copy);
1125                         if (rc) {
1126                                 pr_err("Failed resending result. This flow is not handled - skb ignored\n");
1127                                 kfree_skb(skb_copy);
1128                                 rc = RESPST_CLEANUP;
1129                                 goto out;
1130                         }
1131                 }
1132
1133                 /* Resource not found. Class D error. Drop the request. */
1134                 rc = RESPST_CLEANUP;
1135                 goto out;
1136         }
1137 out:
1138         return rc;
1139 }
1140
1141 /* Process a class A or C. Both are treated the same in this implementation. */
1142 static void do_class_ac_error(struct rxe_qp *qp, u8 syndrome,
1143                               enum ib_wc_status status)
1144 {
1145         qp->resp.aeth_syndrome  = syndrome;
1146         qp->resp.status         = status;
1147
1148         /* indicate that we should go through the ERROR state */
1149         qp->resp.goto_error     = 1;
1150 }
1151
1152 static enum resp_states do_class_d1e_error(struct rxe_qp *qp)
1153 {
1154         /* UC */
1155         if (qp->srq) {
1156                 /* Class E */
1157                 qp->resp.drop_msg = 1;
1158                 if (qp->resp.wqe) {
1159                         qp->resp.status = IB_WC_REM_INV_REQ_ERR;
1160                         return RESPST_COMPLETE;
1161                 } else {
1162                         return RESPST_CLEANUP;
1163                 }
1164         } else {
1165                 /* Class D1. This packet may be the start of a
1166                  * new message and could be valid. The previous
1167                  * message is invalid and ignored. reset the
1168                  * recv wr to its original state
1169                  */
1170                 if (qp->resp.wqe) {
1171                         qp->resp.wqe->dma.resid = qp->resp.wqe->dma.length;
1172                         qp->resp.wqe->dma.cur_sge = 0;
1173                         qp->resp.wqe->dma.sge_offset = 0;
1174                         qp->resp.opcode = -1;
1175                 }
1176
1177                 if (qp->resp.mr) {
1178                         rxe_drop_ref(qp->resp.mr);
1179                         qp->resp.mr = NULL;
1180                 }
1181
1182                 return RESPST_CLEANUP;
1183         }
1184 }
1185
1186 int rxe_responder(void *arg)
1187 {
1188         struct rxe_qp *qp = (struct rxe_qp *)arg;
1189         enum resp_states state;
1190         struct rxe_pkt_info *pkt = NULL;
1191         int ret = 0;
1192
1193         qp->resp.aeth_syndrome = AETH_ACK_UNLIMITED;
1194
1195         if (!qp->valid) {
1196                 ret = -EINVAL;
1197                 goto done;
1198         }
1199
1200         switch (qp->resp.state) {
1201         case QP_STATE_RESET:
1202                 state = RESPST_RESET;
1203                 break;
1204
1205         default:
1206                 state = RESPST_GET_REQ;
1207                 break;
1208         }
1209
1210         while (1) {
1211                 pr_debug("state = %s\n", resp_state_name[state]);
1212                 switch (state) {
1213                 case RESPST_GET_REQ:
1214                         state = get_req(qp, &pkt);
1215                         break;
1216                 case RESPST_CHK_PSN:
1217                         state = check_psn(qp, pkt);
1218                         break;
1219                 case RESPST_CHK_OP_SEQ:
1220                         state = check_op_seq(qp, pkt);
1221                         break;
1222                 case RESPST_CHK_OP_VALID:
1223                         state = check_op_valid(qp, pkt);
1224                         break;
1225                 case RESPST_CHK_RESOURCE:
1226                         state = check_resource(qp, pkt);
1227                         break;
1228                 case RESPST_CHK_LENGTH:
1229                         state = check_length(qp, pkt);
1230                         break;
1231                 case RESPST_CHK_RKEY:
1232                         state = check_rkey(qp, pkt);
1233                         break;
1234                 case RESPST_EXECUTE:
1235                         state = execute(qp, pkt);
1236                         break;
1237                 case RESPST_COMPLETE:
1238                         state = do_complete(qp, pkt);
1239                         break;
1240                 case RESPST_READ_REPLY:
1241                         state = read_reply(qp, pkt);
1242                         break;
1243                 case RESPST_ACKNOWLEDGE:
1244                         state = acknowledge(qp, pkt);
1245                         break;
1246                 case RESPST_CLEANUP:
1247                         state = cleanup(qp, pkt);
1248                         break;
1249                 case RESPST_DUPLICATE_REQUEST:
1250                         state = duplicate_request(qp, pkt);
1251                         break;
1252                 case RESPST_ERR_PSN_OUT_OF_SEQ:
1253                         /* RC only - Class B. Drop packet. */
1254                         send_ack(qp, pkt, AETH_NAK_PSN_SEQ_ERROR, qp->resp.psn);
1255                         state = RESPST_CLEANUP;
1256                         break;
1257
1258                 case RESPST_ERR_TOO_MANY_RDMA_ATM_REQ:
1259                 case RESPST_ERR_MISSING_OPCODE_FIRST:
1260                 case RESPST_ERR_MISSING_OPCODE_LAST_C:
1261                 case RESPST_ERR_UNSUPPORTED_OPCODE:
1262                 case RESPST_ERR_MISALIGNED_ATOMIC:
1263                         /* RC Only - Class C. */
1264                         do_class_ac_error(qp, AETH_NAK_INVALID_REQ,
1265                                           IB_WC_REM_INV_REQ_ERR);
1266                         state = RESPST_COMPLETE;
1267                         break;
1268
1269                 case RESPST_ERR_MISSING_OPCODE_LAST_D1E:
1270                         state = do_class_d1e_error(qp);
1271                         break;
1272                 case RESPST_ERR_RNR:
1273                         if (qp_type(qp) == IB_QPT_RC) {
1274                                 /* RC - class B */
1275                                 send_ack(qp, pkt, AETH_RNR_NAK |
1276                                          (~AETH_TYPE_MASK &
1277                                          qp->attr.min_rnr_timer),
1278                                          pkt->psn);
1279                         } else {
1280                                 /* UD/UC - class D */
1281                                 qp->resp.drop_msg = 1;
1282                         }
1283                         state = RESPST_CLEANUP;
1284                         break;
1285
1286                 case RESPST_ERR_RKEY_VIOLATION:
1287                         if (qp_type(qp) == IB_QPT_RC) {
1288                                 /* Class C */
1289                                 do_class_ac_error(qp, AETH_NAK_REM_ACC_ERR,
1290                                                   IB_WC_REM_ACCESS_ERR);
1291                                 state = RESPST_COMPLETE;
1292                         } else {
1293                                 qp->resp.drop_msg = 1;
1294                                 if (qp->srq) {
1295                                         /* UC/SRQ Class D */
1296                                         qp->resp.status = IB_WC_REM_ACCESS_ERR;
1297                                         state = RESPST_COMPLETE;
1298                                 } else {
1299                                         /* UC/non-SRQ Class E. */
1300                                         state = RESPST_CLEANUP;
1301                                 }
1302                         }
1303                         break;
1304
1305                 case RESPST_ERR_LENGTH:
1306                         if (qp_type(qp) == IB_QPT_RC) {
1307                                 /* Class C */
1308                                 do_class_ac_error(qp, AETH_NAK_INVALID_REQ,
1309                                                   IB_WC_REM_INV_REQ_ERR);
1310                                 state = RESPST_COMPLETE;
1311                         } else if (qp->srq) {
1312                                 /* UC/UD - class E */
1313                                 qp->resp.status = IB_WC_REM_INV_REQ_ERR;
1314                                 state = RESPST_COMPLETE;
1315                         } else {
1316                                 /* UC/UD - class D */
1317                                 qp->resp.drop_msg = 1;
1318                                 state = RESPST_CLEANUP;
1319                         }
1320                         break;
1321
1322                 case RESPST_ERR_MALFORMED_WQE:
1323                         /* All, Class A. */
1324                         do_class_ac_error(qp, AETH_NAK_REM_OP_ERR,
1325                                           IB_WC_LOC_QP_OP_ERR);
1326                         state = RESPST_COMPLETE;
1327                         break;
1328
1329                 case RESPST_ERR_CQ_OVERFLOW:
1330                         /* All - Class G */
1331                         state = RESPST_ERROR;
1332                         break;
1333
1334                 case RESPST_DONE:
1335                         if (qp->resp.goto_error) {
1336                                 state = RESPST_ERROR;
1337                                 break;
1338                         }
1339
1340                         goto done;
1341
1342                 case RESPST_EXIT:
1343                         if (qp->resp.goto_error) {
1344                                 state = RESPST_ERROR;
1345                                 break;
1346                         }
1347
1348                         goto exit;
1349
1350                 case RESPST_RESET: {
1351                         struct sk_buff *skb;
1352
1353                         while ((skb = skb_dequeue(&qp->req_pkts))) {
1354                                 rxe_drop_ref(qp);
1355                                 kfree_skb(skb);
1356                         }
1357
1358                         while (!qp->srq && qp->rq.queue &&
1359                                queue_head(qp->rq.queue))
1360                                 advance_consumer(qp->rq.queue);
1361
1362                         qp->resp.wqe = NULL;
1363                         goto exit;
1364                 }
1365
1366                 case RESPST_ERROR:
1367                         qp->resp.goto_error = 0;
1368                         pr_warn("qp#%d moved to error state\n", qp_num(qp));
1369                         rxe_qp_error(qp);
1370                         goto exit;
1371
1372                 default:
1373                         WARN_ON(1);
1374                 }
1375         }
1376
1377 exit:
1378         ret = -EAGAIN;
1379 done:
1380         return ret;
1381 }