drivers/infiniband/hw/hfi1/rc.c

   1 /*
   2  * Copyright(c) 2015 - 2018 Intel Corporation.
   3  *
   4  * This file is provided under a dual BSD/GPLv2 license.  When using or
   5  * redistributing this file, you may do so under either license.
   6  *
   7  * GPL LICENSE SUMMARY
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * BSD LICENSE
  19  *
  20  * Redistribution and use in source and binary forms, with or without
  21  * modification, are permitted provided that the following conditions
  22  * are met:
  23  *
  24  *  - Redistributions of source code must retain the above copyright
  25  *    notice, this list of conditions and the following disclaimer.
  26  *  - Redistributions in binary form must reproduce the above copyright
  27  *    notice, this list of conditions and the following disclaimer in
  28  *    the documentation and/or other materials provided with the
  29  *    distribution.
  30  *  - Neither the name of Intel Corporation nor the names of its
  31  *    contributors may be used to endorse or promote products derived
  32  *    from this software without specific prior written permission.
  33  *
  34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  45  *
  46  */
  47
  48 #include <linux/io.h>
  49 #include <rdma/rdma_vt.h>
  50 #include <rdma/rdmavt_qp.h>
  51
  52 #include "hfi.h"
  53 #include "qp.h"
  54 #include "rc.h"
  55 #include "verbs_txreq.h"
  56 #include "trace.h"
  57
  58 struct rvt_ack_entry *find_prev_entry(struct rvt_qp *qp, u32 psn, u8 *prev,
  59                                       u8 *prev_ack, bool *scheduled)
  60         __must_hold(&qp->s_lock)
  61 {
  62         struct rvt_ack_entry *e = NULL;
  63         u8 i, p;
  64         bool s = true;
  65
  66         for (i = qp->r_head_ack_queue; ; i = p) {
  67                 if (i == qp->s_tail_ack_queue)
  68                         s = false;
  69                 if (i)
  70                         p = i - 1;
  71                 else
  72                         p = rvt_size_atomic(ib_to_rvt(qp->ibqp.device));
  73                 if (p == qp->r_head_ack_queue) {
  74                         e = NULL;
  75                         break;
  76                 }
  77                 e = &qp->s_ack_queue[p];
  78                 if (!e->opcode) {
  79                         e = NULL;
  80                         break;
  81                 }
  82                 if (cmp_psn(psn, e->psn) >= 0) {
  83                         if (p == qp->s_tail_ack_queue &&
  84                             cmp_psn(psn, e->lpsn) <= 0)
  85                                 s = false;
  86                         break;
  87                 }
  88         }
  89         if (prev)
  90                 *prev = p;
  91         if (prev_ack)
  92                 *prev_ack = i;
  93         if (scheduled)
  94                 *scheduled = s;
  95         return e;
  96 }
  97
  98 /**
  99  * make_rc_ack - construct a response packet (ACK, NAK, or RDMA read)
 100  * @dev: the device for this QP
 101  * @qp: a pointer to the QP
 102  * @ohdr: a pointer to the IB header being constructed
 103  * @ps: the xmit packet state
 104  *
 105  * Return 1 if constructed; otherwise, return 0.
 106  * Note that we are in the responder's side of the QP context.
 107  * Note the QP s_lock must be held.
 108  */
 109 static int make_rc_ack(struct hfi1_ibdev *dev, struct rvt_qp *qp,
 110                        struct ib_other_headers *ohdr,
 111                        struct hfi1_pkt_state *ps)
 112 {
 113         struct rvt_ack_entry *e;
 114         u32 hwords, hdrlen;
 115         u32 len = 0;
 116         u32 bth0 = 0, bth2 = 0;
 117         u32 bth1 = qp->remote_qpn | (HFI1_CAP_IS_KSET(OPFN) << IB_BTHE_E_SHIFT);
 118         int middle = 0;
 119         u32 pmtu = qp->pmtu;
 120         struct hfi1_qp_priv *qpriv = qp->priv;
 121         bool last_pkt;
 122         u32 delta;
 123         u8 next = qp->s_tail_ack_queue;
 124         struct tid_rdma_request *req;
 125
 126         trace_hfi1_rsp_make_rc_ack(qp, 0);
 127         lockdep_assert_held(&qp->s_lock);
 128         /* Don't send an ACK if we aren't supposed to. */
 129         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
 130                 goto bail;
 131
 132         if (qpriv->hdr_type == HFI1_PKT_TYPE_9B)
 133                 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
 134                 hwords = 5;
 135         else
 136                 /* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
 137                 hwords = 7;
 138
 139         switch (qp->s_ack_state) {
 140         case OP(RDMA_READ_RESPONSE_LAST):
 141         case OP(RDMA_READ_RESPONSE_ONLY):
 142                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
 143                 release_rdma_sge_mr(e);
 144                 /* FALLTHROUGH */
 145         case OP(ATOMIC_ACKNOWLEDGE):
 146                 /*
 147                  * We can increment the tail pointer now that the last
 148                  * response has been sent instead of only being
 149                  * constructed.
 150                  */
 151                 if (++next > rvt_size_atomic(&dev->rdi))
 152                         next = 0;
 153                 /*
 154                  * Only advance the s_acked_ack_queue pointer if there
 155                  * have been no TID RDMA requests.
 156                  */
 157                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
 158                 if (e->opcode != TID_OP(WRITE_REQ) &&
 159                     qp->s_acked_ack_queue == qp->s_tail_ack_queue)
 160                         qp->s_acked_ack_queue = next;
 161                 qp->s_tail_ack_queue = next;
 162                 trace_hfi1_rsp_make_rc_ack(qp, e->psn);
 163                 /* FALLTHROUGH */
 164         case OP(SEND_ONLY):
 165         case OP(ACKNOWLEDGE):
 166                 /* Check for no next entry in the queue. */
 167                 if (qp->r_head_ack_queue == qp->s_tail_ack_queue) {
 168                         if (qp->s_flags & RVT_S_ACK_PENDING)
 169                                 goto normal;
 170                         goto bail;
 171                 }
 172
 173                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
 174                 /* Check for tid write fence */
 175                 if ((qpriv->s_flags & HFI1_R_TID_WAIT_INTERLCK) ||
 176                     hfi1_tid_rdma_ack_interlock(qp, e)) {
 177                         iowait_set_flag(&qpriv->s_iowait, IOWAIT_PENDING_IB);
 178                         goto bail;
 179                 }
 180                 if (e->opcode == OP(RDMA_READ_REQUEST)) {
 181                         /*
 182                          * If a RDMA read response is being resent and
 183                          * we haven't seen the duplicate request yet,
 184                          * then stop sending the remaining responses the
 185                          * responder has seen until the requester re-sends it.
 186                          */
 187                         len = e->rdma_sge.sge_length;
 188                         if (len && !e->rdma_sge.mr) {
 189                                 if (qp->s_acked_ack_queue ==
 190                                     qp->s_tail_ack_queue)
 191                                         qp->s_acked_ack_queue =
 192                                                 qp->r_head_ack_queue;
 193                                 qp->s_tail_ack_queue = qp->r_head_ack_queue;
 194                                 goto bail;
 195                         }
 196                         /* Copy SGE state in case we need to resend */
 197                         ps->s_txreq->mr = e->rdma_sge.mr;
 198                         if (ps->s_txreq->mr)
 199                                 rvt_get_mr(ps->s_txreq->mr);
 200                         qp->s_ack_rdma_sge.sge = e->rdma_sge;
 201                         qp->s_ack_rdma_sge.num_sge = 1;
 202                         ps->s_txreq->ss = &qp->s_ack_rdma_sge;
 203                         if (len > pmtu) {
 204                                 len = pmtu;
 205                                 qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST);
 206                         } else {
 207                                 qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY);
 208                                 e->sent = 1;
 209                         }
 210                         ohdr->u.aeth = rvt_compute_aeth(qp);
 211                         hwords++;
 212                         qp->s_ack_rdma_psn = e->psn;
 213                         bth2 = mask_psn(qp->s_ack_rdma_psn++);
 214                 } else if (e->opcode == TID_OP(WRITE_REQ)) {
 215                         /*
 216                          * If a TID RDMA WRITE RESP is being resent, we have to
 217                          * wait for the actual request. All requests that are to
 218                          * be resent will have their state set to
 219                          * TID_REQUEST_RESEND. When the new request arrives, the
 220                          * state will be changed to TID_REQUEST_RESEND_ACTIVE.
 221                          */
 222                         req = ack_to_tid_req(e);
 223                         if (req->state == TID_REQUEST_RESEND ||
 224                             req->state == TID_REQUEST_INIT_RESEND)
 225                                 goto bail;
 226                         qp->s_ack_state = TID_OP(WRITE_RESP);
 227                         qp->s_ack_rdma_psn = mask_psn(e->psn + req->cur_seg);
 228                         goto write_resp;
 229                 } else if (e->opcode == TID_OP(READ_REQ)) {
 230                         /*
 231                          * If a TID RDMA read response is being resent and
 232                          * we haven't seen the duplicate request yet,
 233                          * then stop sending the remaining responses the
 234                          * responder has seen until the requester re-sends it.
 235                          */
 236                         len = e->rdma_sge.sge_length;
 237                         if (len && !e->rdma_sge.mr) {
 238                                 if (qp->s_acked_ack_queue ==
 239                                     qp->s_tail_ack_queue)
 240                                         qp->s_acked_ack_queue =
 241                                                 qp->r_head_ack_queue;
 242                                 qp->s_tail_ack_queue = qp->r_head_ack_queue;
 243                                 goto bail;
 244                         }
 245                         /* Copy SGE state in case we need to resend */
 246                         ps->s_txreq->mr = e->rdma_sge.mr;
 247                         if (ps->s_txreq->mr)
 248                                 rvt_get_mr(ps->s_txreq->mr);
 249                         qp->s_ack_rdma_sge.sge = e->rdma_sge;
 250                         qp->s_ack_rdma_sge.num_sge = 1;
 251                         qp->s_ack_state = TID_OP(READ_RESP);
 252                         goto read_resp;
 253                 } else {
 254                         /* COMPARE_SWAP or FETCH_ADD */
 255                         ps->s_txreq->ss = NULL;
 256                         len = 0;
 257                         qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
 258                         ohdr->u.at.aeth = rvt_compute_aeth(qp);
 259                         ib_u64_put(e->atomic_data, &ohdr->u.at.atomic_ack_eth);
 260                         hwords += sizeof(ohdr->u.at) / sizeof(u32);
 261                         bth2 = mask_psn(e->psn);
 262                         e->sent = 1;
 263                 }
 264                 trace_hfi1_tid_write_rsp_make_rc_ack(qp);
 265                 bth0 = qp->s_ack_state << 24;
 266                 break;
 267
 268         case OP(RDMA_READ_RESPONSE_FIRST):
 269                 qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE);
 270                 /* FALLTHROUGH */
 271         case OP(RDMA_READ_RESPONSE_MIDDLE):
 272                 ps->s_txreq->ss = &qp->s_ack_rdma_sge;
 273                 ps->s_txreq->mr = qp->s_ack_rdma_sge.sge.mr;
 274                 if (ps->s_txreq->mr)
 275                         rvt_get_mr(ps->s_txreq->mr);
 276                 len = qp->s_ack_rdma_sge.sge.sge_length;
 277                 if (len > pmtu) {
 278                         len = pmtu;
 279                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
 280                 } else {
 281                         ohdr->u.aeth = rvt_compute_aeth(qp);
 282                         hwords++;
 283                         qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
 284                         e = &qp->s_ack_queue[qp->s_tail_ack_queue];
 285                         e->sent = 1;
 286                 }
 287                 bth0 = qp->s_ack_state << 24;
 288                 bth2 = mask_psn(qp->s_ack_rdma_psn++);
 289                 break;
 290
 291         case TID_OP(WRITE_RESP):
 292 write_resp:
 293                 /*
 294                  * 1. Check if RVT_S_ACK_PENDING is set. If yes,
 295                  *    goto normal.
 296                  * 2. Attempt to allocate TID resources.
 297                  * 3. Remove RVT_S_RESP_PENDING flags from s_flags
 298                  * 4. If resources not available:
 299                  *    4.1 Set RVT_S_WAIT_TID_SPACE
 300                  *    4.2 Queue QP on RCD TID queue
 301                  *    4.3 Put QP on iowait list.
 302                  *    4.4 Build IB RNR NAK with appropriate timeout value
 303                  *    4.5 Return indication progress made.
 304                  * 5. If resources are available:
 305                  *    5.1 Program HW flow CSRs
 306                  *    5.2 Build TID RDMA WRITE RESP packet
 307                  *    5.3 If more resources needed, do 2.1 - 2.3.
 308                  *    5.4 Wake up next QP on RCD TID queue.
 309                  *    5.5 Return indication progress made.
 310                  */
 311
 312                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
 313                 req = ack_to_tid_req(e);
 314
 315                 /*
 316                  * Send scheduled RNR NAK's. RNR NAK's need to be sent at
 317                  * segment boundaries, not at request boundaries. Don't change
 318                  * s_ack_state because we are still in the middle of a request
 319                  */
 320                 if (qpriv->rnr_nak_state == TID_RNR_NAK_SEND &&
 321                     qp->s_tail_ack_queue == qpriv->r_tid_alloc &&
 322                     req->cur_seg == req->alloc_seg) {
 323                         qpriv->rnr_nak_state = TID_RNR_NAK_SENT;
 324                         goto normal_no_state;
 325                 }
 326
 327                 bth2 = mask_psn(qp->s_ack_rdma_psn);
 328                 hdrlen = hfi1_build_tid_rdma_write_resp(qp, e, ohdr, &bth1,
 329                                                         bth2, &len,
 330                                                         &ps->s_txreq->ss);
 331                 if (!hdrlen)
 332                         return 0;
 333
 334                 hwords += hdrlen;
 335                 bth0 = qp->s_ack_state << 24;
 336                 qp->s_ack_rdma_psn++;
 337                 trace_hfi1_tid_req_make_rc_ack_write(qp, 0, e->opcode, e->psn,
 338                                                      e->lpsn, req);
 339                 if (req->cur_seg != req->total_segs)
 340                         break;
 341
 342                 e->sent = 1;
 343                 /* Do not free e->rdma_sge until all data are received */
 344                 qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
 345                 break;
 346
 347         case TID_OP(READ_RESP):
 348 read_resp:
 349                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
 350                 ps->s_txreq->ss = &qp->s_ack_rdma_sge;
 351                 delta = hfi1_build_tid_rdma_read_resp(qp, e, ohdr, &bth0,
 352                                                       &bth1, &bth2, &len,
 353                                                       &last_pkt);
 354                 if (delta == 0)
 355                         goto error_qp;
 356                 hwords += delta;
 357                 if (last_pkt) {
 358                         e->sent = 1;
 359                         /*
 360                          * Increment qp->s_tail_ack_queue through s_ack_state
 361                          * transition.
 362                          */
 363                         qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
 364                 }
 365                 break;
 366         case TID_OP(READ_REQ):
 367                 goto bail;
 368
 369         default:
 370 normal:
 371                 /*
 372                  * Send a regular ACK.
 373                  * Set the s_ack_state so we wait until after sending
 374                  * the ACK before setting s_ack_state to ACKNOWLEDGE
 375                  * (see above).
 376                  */
 377                 qp->s_ack_state = OP(SEND_ONLY);
 378 normal_no_state:
 379                 if (qp->s_nak_state)
 380                         ohdr->u.aeth =
 381                                 cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
 382                                             (qp->s_nak_state <<
 383                                              IB_AETH_CREDIT_SHIFT));
 384                 else
 385                         ohdr->u.aeth = rvt_compute_aeth(qp);
 386                 hwords++;
 387                 len = 0;
 388                 bth0 = OP(ACKNOWLEDGE) << 24;
 389                 bth2 = mask_psn(qp->s_ack_psn);
 390                 qp->s_flags &= ~RVT_S_ACK_PENDING;
 391                 ps->s_txreq->txreq.flags |= SDMA_TXREQ_F_VIP;
 392                 ps->s_txreq->ss = NULL;
 393         }
 394         qp->s_rdma_ack_cnt++;
 395         ps->s_txreq->sde = qpriv->s_sde;
 396         ps->s_txreq->s_cur_size = len;
 397         ps->s_txreq->hdr_dwords = hwords;
 398         hfi1_make_ruc_header(qp, ohdr, bth0, bth1, bth2, middle, ps);
 399         return 1;
 400 error_qp:
 401         spin_unlock_irqrestore(&qp->s_lock, ps->flags);
 402         spin_lock_irqsave(&qp->r_lock, ps->flags);
 403         spin_lock(&qp->s_lock);
 404         rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
 405         spin_unlock(&qp->s_lock);
 406         spin_unlock_irqrestore(&qp->r_lock, ps->flags);
 407         spin_lock_irqsave(&qp->s_lock, ps->flags);
 408 bail:
 409         qp->s_ack_state = OP(ACKNOWLEDGE);
 410         /*
 411          * Ensure s_rdma_ack_cnt changes are committed prior to resetting
 412          * RVT_S_RESP_PENDING
 413          */
 414         smp_wmb();
 415         qp->s_flags &= ~(RVT_S_RESP_PENDING
 416                                 | RVT_S_ACK_PENDING
 417                                 | HFI1_S_AHG_VALID);
 418         return 0;
 419 }
 420
 421 /**
 422  * hfi1_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC)
 423  * @qp: a pointer to the QP
 424  *
 425  * Assumes s_lock is held.
 426  *
 427  * Return 1 if constructed; otherwise, return 0.
 428  */
 429 int hfi1_make_rc_req(struct rvt_qp *qp, struct hfi1_pkt_state *ps)
 430 {
 431         struct hfi1_qp_priv *priv = qp->priv;
 432         struct hfi1_ibdev *dev = to_idev(qp->ibqp.device);
 433         struct ib_other_headers *ohdr;
 434         struct rvt_sge_state *ss = NULL;
 435         struct rvt_swqe *wqe;
 436         struct hfi1_swqe_priv *wpriv;
 437         struct tid_rdma_request *req = NULL;
 438         /* header size in 32-bit words LRH+BTH = (8+12)/4. */
 439         u32 hwords = 5;
 440         u32 len = 0;
 441         u32 bth0 = 0, bth2 = 0;
 442         u32 bth1 = qp->remote_qpn | (HFI1_CAP_IS_KSET(OPFN) << IB_BTHE_E_SHIFT);
 443         u32 pmtu = qp->pmtu;
 444         char newreq;
 445         int middle = 0;
 446         int delta;
 447         struct tid_rdma_flow *flow = NULL;
 448         struct tid_rdma_params *remote;
 449
 450         trace_hfi1_sender_make_rc_req(qp);
 451         lockdep_assert_held(&qp->s_lock);
 452         ps->s_txreq = get_txreq(ps->dev, qp);
 453         if (!ps->s_txreq)
 454                 goto bail_no_tx;
 455
 456         if (priv->hdr_type == HFI1_PKT_TYPE_9B) {
 457                 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
 458                 hwords = 5;
 459                 if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)
 460                         ohdr = &ps->s_txreq->phdr.hdr.ibh.u.l.oth;
 461                 else
 462                         ohdr = &ps->s_txreq->phdr.hdr.ibh.u.oth;
 463         } else {
 464                 /* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
 465                 hwords = 7;
 466                 if ((rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
 467                     (hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))))
 468                         ohdr = &ps->s_txreq->phdr.hdr.opah.u.l.oth;
 469                 else
 470                         ohdr = &ps->s_txreq->phdr.hdr.opah.u.oth;
 471         }
 472
 473         /* Sending responses has higher priority over sending requests. */
 474         if ((qp->s_flags & RVT_S_RESP_PENDING) &&
 475             make_rc_ack(dev, qp, ohdr, ps))
 476                 return 1;
 477
 478         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
 479                 if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND))
 480                         goto bail;
 481                 /* We are in the error state, flush the work request. */
 482                 if (qp->s_last == READ_ONCE(qp->s_head))
 483                         goto bail;
 484                 /* If DMAs are in progress, we can't flush immediately. */
 485                 if (iowait_sdma_pending(&priv->s_iowait)) {
 486                         qp->s_flags |= RVT_S_WAIT_DMA;
 487                         goto bail;
 488                 }
 489                 clear_ahg(qp);
 490                 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
 491                 hfi1_trdma_send_complete(qp, wqe, qp->s_last != qp->s_acked ?
 492                                          IB_WC_SUCCESS : IB_WC_WR_FLUSH_ERR);
 493                 /* will get called again */
 494                 goto done_free_tx;
 495         }
 496
 497         if (qp->s_flags & (RVT_S_WAIT_RNR | RVT_S_WAIT_ACK | HFI1_S_WAIT_HALT))
 498                 goto bail;
 499
 500         if (cmp_psn(qp->s_psn, qp->s_sending_hpsn) <= 0) {
 501                 if (cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0) {
 502                         qp->s_flags |= RVT_S_WAIT_PSN;
 503                         goto bail;
 504                 }
 505                 qp->s_sending_psn = qp->s_psn;
 506                 qp->s_sending_hpsn = qp->s_psn - 1;
 507         }
 508
 509         /* Send a request. */
 510         wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
 511 check_s_state:
 512         switch (qp->s_state) {
 513         default:
 514                 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_NEXT_SEND_OK))
 515                         goto bail;
 516                 /*
 517                  * Resend an old request or start a new one.
 518                  *
 519                  * We keep track of the current SWQE so that
 520                  * we don't reset the "furthest progress" state
 521                  * if we need to back up.
 522                  */
 523                 newreq = 0;
 524                 if (qp->s_cur == qp->s_tail) {
 525                         /* Check if send work queue is empty. */
 526                         if (qp->s_tail == READ_ONCE(qp->s_head)) {
 527                                 clear_ahg(qp);
 528                                 goto bail;
 529                         }
 530                         /*
 531                          * If a fence is requested, wait for previous
 532                          * RDMA read and atomic operations to finish.
 533                          * However, there is no need to guard against
 534                          * TID RDMA READ after TID RDMA READ.
 535                          */
 536                         if ((wqe->wr.send_flags & IB_SEND_FENCE) &&
 537                             qp->s_num_rd_atomic &&
 538                             (wqe->wr.opcode != IB_WR_TID_RDMA_READ ||
 539                              priv->pending_tid_r_segs < qp->s_num_rd_atomic)) {
 540                                 qp->s_flags |= RVT_S_WAIT_FENCE;
 541                                 goto bail;
 542                         }
 543                         /*
 544                          * Local operations are processed immediately
 545                          * after all prior requests have completed
 546                          */
 547                         if (wqe->wr.opcode == IB_WR_REG_MR ||
 548                             wqe->wr.opcode == IB_WR_LOCAL_INV) {
 549                                 int local_ops = 0;
 550                                 int err = 0;
 551
 552                                 if (qp->s_last != qp->s_cur)
 553                                         goto bail;
 554                                 if (++qp->s_cur == qp->s_size)
 555                                         qp->s_cur = 0;
 556                                 if (++qp->s_tail == qp->s_size)
 557                                         qp->s_tail = 0;
 558                                 if (!(wqe->wr.send_flags &
 559                                       RVT_SEND_COMPLETION_ONLY)) {
 560                                         err = rvt_invalidate_rkey(
 561                                                 qp,
 562                                                 wqe->wr.ex.invalidate_rkey);
 563                                         local_ops = 1;
 564                                 }
 565                                 rvt_send_complete(qp, wqe,
 566                                                   err ? IB_WC_LOC_PROT_ERR
 567                                                       : IB_WC_SUCCESS);
 568                                 if (local_ops)
 569                                         atomic_dec(&qp->local_ops_pending);
 570                                 goto done_free_tx;
 571                         }
 572
 573                         newreq = 1;
 574                         qp->s_psn = wqe->psn;
 575                 }
 576                 /*
 577                  * Note that we have to be careful not to modify the
 578                  * original work request since we may need to resend
 579                  * it.
 580                  */
 581                 len = wqe->length;
 582                 ss = &qp->s_sge;
 583                 bth2 = mask_psn(qp->s_psn);
 584
 585                 /*
 586                  * Interlock between various IB requests and TID RDMA
 587                  * if necessary.
 588                  */
 589                 if ((priv->s_flags & HFI1_S_TID_WAIT_INTERLCK) ||
 590                     hfi1_tid_rdma_wqe_interlock(qp, wqe))
 591                         goto bail;
 592
 593                 switch (wqe->wr.opcode) {
 594                 case IB_WR_SEND:
 595                 case IB_WR_SEND_WITH_IMM:
 596                 case IB_WR_SEND_WITH_INV:
 597                         /* If no credit, return. */
 598                         if (!rvt_rc_credit_avail(qp, wqe))
 599                                 goto bail;
 600                         if (len > pmtu) {
 601                                 qp->s_state = OP(SEND_FIRST);
 602                                 len = pmtu;
 603                                 break;
 604                         }
 605                         if (wqe->wr.opcode == IB_WR_SEND) {
 606                                 qp->s_state = OP(SEND_ONLY);
 607                         } else if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
 608                                 qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE);
 609                                 /* Immediate data comes after the BTH */
 610                                 ohdr->u.imm_data = wqe->wr.ex.imm_data;
 611                                 hwords += 1;
 612                         } else {
 613                                 qp->s_state = OP(SEND_ONLY_WITH_INVALIDATE);
 614                                 /* Invalidate rkey comes after the BTH */
 615                                 ohdr->u.ieth = cpu_to_be32(
 616                                                 wqe->wr.ex.invalidate_rkey);
 617                                 hwords += 1;
 618                         }
 619                         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 620                                 bth0 |= IB_BTH_SOLICITED;
 621                         bth2 |= IB_BTH_REQ_ACK;
 622                         if (++qp->s_cur == qp->s_size)
 623                                 qp->s_cur = 0;
 624                         break;
 625
 626                 case IB_WR_RDMA_WRITE:
 627                         if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
 628                                 qp->s_lsn++;
 629                         goto no_flow_control;
 630                 case IB_WR_RDMA_WRITE_WITH_IMM:
 631                         /* If no credit, return. */
 632                         if (!rvt_rc_credit_avail(qp, wqe))
 633                                 goto bail;
 634 no_flow_control:
 635                         put_ib_reth_vaddr(
 636                                 wqe->rdma_wr.remote_addr,
 637                                 &ohdr->u.rc.reth);
 638                         ohdr->u.rc.reth.rkey =
 639                                 cpu_to_be32(wqe->rdma_wr.rkey);
 640                         ohdr->u.rc.reth.length = cpu_to_be32(len);
 641                         hwords += sizeof(struct ib_reth) / sizeof(u32);
 642                         if (len > pmtu) {
 643                                 qp->s_state = OP(RDMA_WRITE_FIRST);
 644                                 len = pmtu;
 645                                 break;
 646                         }
 647                         if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
 648                                 qp->s_state = OP(RDMA_WRITE_ONLY);
 649                         } else {
 650                                 qp->s_state =
 651                                         OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE);
 652                                 /* Immediate data comes after RETH */
 653                                 ohdr->u.rc.imm_data = wqe->wr.ex.imm_data;
 654                                 hwords += 1;
 655                                 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 656                                         bth0 |= IB_BTH_SOLICITED;
 657                         }
 658                         bth2 |= IB_BTH_REQ_ACK;
 659                         if (++qp->s_cur == qp->s_size)
 660                                 qp->s_cur = 0;
 661                         break;
 662
 663                 case IB_WR_TID_RDMA_WRITE:
 664                         if (newreq) {
 665                                 /*
 666                                  * Limit the number of TID RDMA WRITE requests.
 667                                  */
 668                                 if (atomic_read(&priv->n_tid_requests) >=
 669                                     HFI1_TID_RDMA_WRITE_CNT)
 670                                         goto bail;
 671
 672                                 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
 673                                         qp->s_lsn++;
 674                         }
 675
 676                         hwords += hfi1_build_tid_rdma_write_req(qp, wqe, ohdr,
 677                                                                 &bth1, &bth2,
 678                                                                 &len);
 679                         ss = NULL;
 680                         if (priv->s_tid_cur == HFI1_QP_WQE_INVALID) {
 681                                 priv->s_tid_cur = qp->s_cur;
 682                                 if (priv->s_tid_tail == HFI1_QP_WQE_INVALID) {
 683                                         priv->s_tid_tail = qp->s_cur;
 684                                         priv->s_state = TID_OP(WRITE_RESP);
 685                                 }
 686                         } else if (priv->s_tid_cur == priv->s_tid_head) {
 687                                 struct rvt_swqe *__w;
 688                                 struct tid_rdma_request *__r;
 689
 690                                 __w = rvt_get_swqe_ptr(qp, priv->s_tid_cur);
 691                                 __r = wqe_to_tid_req(__w);
 692
 693                                 /*
 694                                  * The s_tid_cur pointer is advanced to s_cur if
 695                                  * any of the following conditions about the WQE
 696                                  * to which s_ti_cur currently points to are
 697                                  * satisfied:
 698                                  *   1. The request is not a TID RDMA WRITE
 699                                  *      request,
 700                                  *   2. The request is in the INACTIVE or
 701                                  *      COMPLETE states (TID RDMA READ requests
 702                                  *      stay at INACTIVE and TID RDMA WRITE
 703                                  *      transition to COMPLETE when done),
 704                                  *   3. The request is in the ACTIVE or SYNC
 705                                  *      state and the number of completed
 706                                  *      segments is equal to the total segment
 707                                  *      count.
 708                                  *      (If ACTIVE, the request is waiting for
 709                                  *       ACKs. If SYNC, the request has not
 710                                  *       received any responses because it's
 711                                  *       waiting on a sync point.)
 712                                  */
 713                                 if (__w->wr.opcode != IB_WR_TID_RDMA_WRITE ||
 714                                     __r->state == TID_REQUEST_INACTIVE ||
 715                                     __r->state == TID_REQUEST_COMPLETE ||
 716                                     ((__r->state == TID_REQUEST_ACTIVE ||
 717                                       __r->state == TID_REQUEST_SYNC) &&
 718                                      __r->comp_seg == __r->total_segs)) {
 719                                         if (priv->s_tid_tail ==
 720                                             priv->s_tid_cur &&
 721                                             priv->s_state ==
 722                                             TID_OP(WRITE_DATA_LAST)) {
 723                                                 priv->s_tid_tail = qp->s_cur;
 724                                                 priv->s_state =
 725                                                         TID_OP(WRITE_RESP);
 726                                         }
 727                                         priv->s_tid_cur = qp->s_cur;
 728                                 }
 729                                 /*
 730                                  * A corner case: when the last TID RDMA WRITE
 731                                  * request was completed, s_tid_head,
 732                                  * s_tid_cur, and s_tid_tail all point to the
 733                                  * same location. Other requests are posted and
 734                                  * s_cur wraps around to the same location,
 735                                  * where a new TID RDMA WRITE is posted. In
 736                                  * this case, none of the indices need to be
 737                                  * updated. However, the priv->s_state should.
 738                                  */
 739                                 if (priv->s_tid_tail == qp->s_cur &&
 740                                     priv->s_state == TID_OP(WRITE_DATA_LAST))
 741                                         priv->s_state = TID_OP(WRITE_RESP);
 742                         }
 743                         req = wqe_to_tid_req(wqe);
 744                         if (newreq) {
 745                                 priv->s_tid_head = qp->s_cur;
 746                                 priv->pending_tid_w_resp += req->total_segs;
 747                                 atomic_inc(&priv->n_tid_requests);
 748                                 atomic_dec(&priv->n_requests);
 749                         } else {
 750                                 req->state = TID_REQUEST_RESEND;
 751                                 req->comp_seg = delta_psn(bth2, wqe->psn);
 752                                 /*
 753                                  * Pull back any segments since we are going
 754                                  * to re-receive them.
 755                                  */
 756                                 req->setup_head = req->clear_tail;
 757                                 priv->pending_tid_w_resp +=
 758                                         delta_psn(wqe->lpsn, bth2) + 1;
 759                         }
 760
 761                         trace_hfi1_tid_write_sender_make_req(qp, newreq);
 762                         trace_hfi1_tid_req_make_req_write(qp, newreq,
 763                                                           wqe->wr.opcode,
 764                                                           wqe->psn, wqe->lpsn,
 765                                                           req);
 766                         if (++qp->s_cur == qp->s_size)
 767                                 qp->s_cur = 0;
 768                         break;
 769
 770                 case IB_WR_RDMA_READ:
 771                         /*
 772                          * Don't allow more operations to be started
 773                          * than the QP limits allow.
 774                          */
 775                         if (qp->s_num_rd_atomic >=
 776                             qp->s_max_rd_atomic) {
 777                                 qp->s_flags |= RVT_S_WAIT_RDMAR;
 778                                 goto bail;
 779                         }
 780                         qp->s_num_rd_atomic++;
 781                         if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
 782                                 qp->s_lsn++;
 783                         put_ib_reth_vaddr(
 784                                 wqe->rdma_wr.remote_addr,
 785                                 &ohdr->u.rc.reth);
 786                         ohdr->u.rc.reth.rkey =
 787                                 cpu_to_be32(wqe->rdma_wr.rkey);
 788                         ohdr->u.rc.reth.length = cpu_to_be32(len);
 789                         qp->s_state = OP(RDMA_READ_REQUEST);
 790                         hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
 791                         ss = NULL;
 792                         len = 0;
 793                         bth2 |= IB_BTH_REQ_ACK;
 794                         if (++qp->s_cur == qp->s_size)
 795                                 qp->s_cur = 0;
 796                         break;
 797
 798                 case IB_WR_TID_RDMA_READ:
 799                         trace_hfi1_tid_read_sender_make_req(qp, newreq);
 800                         wpriv = wqe->priv;
 801                         req = wqe_to_tid_req(wqe);
 802                         trace_hfi1_tid_req_make_req_read(qp, newreq,
 803                                                          wqe->wr.opcode,
 804                                                          wqe->psn, wqe->lpsn,
 805                                                          req);
 806                         delta = cmp_psn(qp->s_psn, wqe->psn);
 807
 808                         /*
 809                          * Don't allow more operations to be started
 810                          * than the QP limits allow. We could get here under
 811                          * three conditions; (1) It's a new request; (2) We are
 812                          * sending the second or later segment of a request,
 813                          * but the qp->s_state is set to OP(RDMA_READ_REQUEST)
 814                          * when the last segment of a previous request is
 815                          * received just before this; (3) We are re-sending a
 816                          * request.
 817                          */
 818                         if (qp->s_num_rd_atomic >= qp->s_max_rd_atomic) {
 819                                 qp->s_flags |= RVT_S_WAIT_RDMAR;
 820                                 goto bail;
 821                         }
 822                         if (newreq) {
 823                                 struct tid_rdma_flow *flow =
 824                                         &req->flows[req->setup_head];
 825
 826                                 /*
 827                                  * Set up s_sge as it is needed for TID
 828                                  * allocation. However, if the pages have been
 829                                  * walked and mapped, skip it. An earlier try
 830                                  * has failed to allocate the TID entries.
 831                                  */
 832                                 if (!flow->npagesets) {
 833                                         qp->s_sge.sge = wqe->sg_list[0];
 834                                         qp->s_sge.sg_list = wqe->sg_list + 1;
 835                                         qp->s_sge.num_sge = wqe->wr.num_sge;
 836                                         qp->s_sge.total_len = wqe->length;
 837                                         qp->s_len = wqe->length;
 838                                         req->isge = 0;
 839                                         req->clear_tail = req->setup_head;
 840                                         req->flow_idx = req->setup_head;
 841                                         req->state = TID_REQUEST_ACTIVE;
 842                                 }
 843                         } else if (delta == 0) {
 844                                 /* Re-send a request */
 845                                 req->cur_seg = 0;
 846                                 req->comp_seg = 0;
 847                                 req->ack_pending = 0;
 848                                 req->flow_idx = req->clear_tail;
 849                                 req->state = TID_REQUEST_RESEND;
 850                         }
 851                         req->s_next_psn = qp->s_psn;
 852                         /* Read one segment at a time */
 853                         len = min_t(u32, req->seg_len,
 854                                     wqe->length - req->seg_len * req->cur_seg);
 855                         delta = hfi1_build_tid_rdma_read_req(qp, wqe, ohdr,
 856                                                              &bth1, &bth2,
 857                                                              &len);
 858                         if (delta <= 0) {
 859                                 /* Wait for TID space */
 860                                 goto bail;
 861                         }
 862                         if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
 863                                 qp->s_lsn++;
 864                         hwords += delta;
 865                         ss = &wpriv->ss;
 866                         /* Check if this is the last segment */
 867                         if (req->cur_seg >= req->total_segs &&
 868                             ++qp->s_cur == qp->s_size)
 869                                 qp->s_cur = 0;
 870                         break;
 871
 872                 case IB_WR_ATOMIC_CMP_AND_SWP:
 873                 case IB_WR_ATOMIC_FETCH_AND_ADD:
 874                         /*
 875                          * Don't allow more operations to be started
 876                          * than the QP limits allow.
 877                          */
 878                         if (qp->s_num_rd_atomic >=
 879                             qp->s_max_rd_atomic) {
 880                                 qp->s_flags |= RVT_S_WAIT_RDMAR;
 881                                 goto bail;
 882                         }
 883                         qp->s_num_rd_atomic++;
 884
 885                         /* FALLTHROUGH */
 886                 case IB_WR_OPFN:
 887                         if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
 888                                 qp->s_lsn++;
 889                         if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
 890                             wqe->wr.opcode == IB_WR_OPFN) {
 891                                 qp->s_state = OP(COMPARE_SWAP);
 892                                 put_ib_ateth_swap(wqe->atomic_wr.swap,
 893                                                   &ohdr->u.atomic_eth);
 894                                 put_ib_ateth_compare(wqe->atomic_wr.compare_add,
 895                                                      &ohdr->u.atomic_eth);
 896                         } else {
 897                                 qp->s_state = OP(FETCH_ADD);
 898                                 put_ib_ateth_swap(wqe->atomic_wr.compare_add,
 899                                                   &ohdr->u.atomic_eth);
 900                                 put_ib_ateth_compare(0, &ohdr->u.atomic_eth);
 901                         }
 902                         put_ib_ateth_vaddr(wqe->atomic_wr.remote_addr,
 903                                            &ohdr->u.atomic_eth);
 904                         ohdr->u.atomic_eth.rkey = cpu_to_be32(
 905                                 wqe->atomic_wr.rkey);
 906                         hwords += sizeof(struct ib_atomic_eth) / sizeof(u32);
 907                         ss = NULL;
 908                         len = 0;
 909                         bth2 |= IB_BTH_REQ_ACK;
 910                         if (++qp->s_cur == qp->s_size)
 911                                 qp->s_cur = 0;
 912                         break;
 913
 914                 default:
 915                         goto bail;
 916                 }
 917                 if (wqe->wr.opcode != IB_WR_TID_RDMA_READ) {
 918                         qp->s_sge.sge = wqe->sg_list[0];
 919                         qp->s_sge.sg_list = wqe->sg_list + 1;
 920                         qp->s_sge.num_sge = wqe->wr.num_sge;
 921                         qp->s_sge.total_len = wqe->length;
 922                         qp->s_len = wqe->length;
 923                 }
 924                 if (newreq) {
 925                         qp->s_tail++;
 926                         if (qp->s_tail >= qp->s_size)
 927                                 qp->s_tail = 0;
 928                 }
 929                 if (wqe->wr.opcode == IB_WR_RDMA_READ ||
 930                     wqe->wr.opcode == IB_WR_TID_RDMA_WRITE)
 931                         qp->s_psn = wqe->lpsn + 1;
 932                 else if (wqe->wr.opcode == IB_WR_TID_RDMA_READ)
 933                         qp->s_psn = req->s_next_psn;
 934                 else
 935                         qp->s_psn++;
 936                 break;
 937
 938         case OP(RDMA_READ_RESPONSE_FIRST):
 939                 /*
 940                  * qp->s_state is normally set to the opcode of the
 941                  * last packet constructed for new requests and therefore
 942                  * is never set to RDMA read response.
 943                  * RDMA_READ_RESPONSE_FIRST is used by the ACK processing
 944                  * thread to indicate a SEND needs to be restarted from an
 945                  * earlier PSN without interfering with the sending thread.
 946                  * See restart_rc().
 947                  */
 948                 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
 949                 /* FALLTHROUGH */
 950         case OP(SEND_FIRST):
 951                 qp->s_state = OP(SEND_MIDDLE);
 952                 /* FALLTHROUGH */
 953         case OP(SEND_MIDDLE):
 954                 bth2 = mask_psn(qp->s_psn++);
 955                 ss = &qp->s_sge;
 956                 len = qp->s_len;
 957                 if (len > pmtu) {
 958                         len = pmtu;
 959                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
 960                         break;
 961                 }
 962                 if (wqe->wr.opcode == IB_WR_SEND) {
 963                         qp->s_state = OP(SEND_LAST);
 964                 } else if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
 965                         qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE);
 966                         /* Immediate data comes after the BTH */
 967                         ohdr->u.imm_data = wqe->wr.ex.imm_data;
 968                         hwords += 1;
 969                 } else {
 970                         qp->s_state = OP(SEND_LAST_WITH_INVALIDATE);
 971                         /* invalidate data comes after the BTH */
 972                         ohdr->u.ieth = cpu_to_be32(wqe->wr.ex.invalidate_rkey);
 973                         hwords += 1;
 974                 }
 975                 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 976                         bth0 |= IB_BTH_SOLICITED;
 977                 bth2 |= IB_BTH_REQ_ACK;
 978                 qp->s_cur++;
 979                 if (qp->s_cur >= qp->s_size)
 980                         qp->s_cur = 0;
 981                 break;
 982
 983         case OP(RDMA_READ_RESPONSE_LAST):
 984                 /*
 985                  * qp->s_state is normally set to the opcode of the
 986                  * last packet constructed for new requests and therefore
 987                  * is never set to RDMA read response.
 988                  * RDMA_READ_RESPONSE_LAST is used by the ACK processing
 989                  * thread to indicate a RDMA write needs to be restarted from
 990                  * an earlier PSN without interfering with the sending thread.
 991                  * See restart_rc().
 992                  */
 993                 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
 994                 /* FALLTHROUGH */
 995         case OP(RDMA_WRITE_FIRST):
 996                 qp->s_state = OP(RDMA_WRITE_MIDDLE);
 997                 /* FALLTHROUGH */
 998         case OP(RDMA_WRITE_MIDDLE):
 999                 bth2 = mask_psn(qp->s_psn++);
1000                 ss = &qp->s_sge;
1001                 len = qp->s_len;
1002                 if (len > pmtu) {
1003                         len = pmtu;
1004                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
1005                         break;
1006                 }
1007                 if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
1008                         qp->s_state = OP(RDMA_WRITE_LAST);
1009                 } else {
1010                         qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE);
1011                         /* Immediate data comes after the BTH */
1012                         ohdr->u.imm_data = wqe->wr.ex.imm_data;
1013                         hwords += 1;
1014                         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
1015                                 bth0 |= IB_BTH_SOLICITED;
1016                 }
1017                 bth2 |= IB_BTH_REQ_ACK;
1018                 qp->s_cur++;
1019                 if (qp->s_cur >= qp->s_size)
1020                         qp->s_cur = 0;
1021                 break;
1022
1023         case OP(RDMA_READ_RESPONSE_MIDDLE):
1024                 /*
1025                  * qp->s_state is normally set to the opcode of the
1026                  * last packet constructed for new requests and therefore
1027                  * is never set to RDMA read response.
1028                  * RDMA_READ_RESPONSE_MIDDLE is used by the ACK processing
1029                  * thread to indicate a RDMA read needs to be restarted from
1030                  * an earlier PSN without interfering with the sending thread.
1031                  * See restart_rc().
1032                  */
1033                 len = (delta_psn(qp->s_psn, wqe->psn)) * pmtu;
1034                 put_ib_reth_vaddr(
1035                         wqe->rdma_wr.remote_addr + len,
1036                         &ohdr->u.rc.reth);
1037                 ohdr->u.rc.reth.rkey =
1038                         cpu_to_be32(wqe->rdma_wr.rkey);
1039                 ohdr->u.rc.reth.length = cpu_to_be32(wqe->length - len);
1040                 qp->s_state = OP(RDMA_READ_REQUEST);
1041                 hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
1042                 bth2 = mask_psn(qp->s_psn) | IB_BTH_REQ_ACK;
1043                 qp->s_psn = wqe->lpsn + 1;
1044                 ss = NULL;
1045                 len = 0;
1046                 qp->s_cur++;
1047                 if (qp->s_cur == qp->s_size)
1048                         qp->s_cur = 0;
1049                 break;
1050
1051         case TID_OP(WRITE_RESP):
1052                 /*
1053                  * This value for s_state is used for restarting a TID RDMA
1054                  * WRITE request. See comment in OP(RDMA_READ_RESPONSE_MIDDLE
1055                  * for more).
1056                  */
1057                 req = wqe_to_tid_req(wqe);
1058                 req->state = TID_REQUEST_RESEND;
1059                 rcu_read_lock();
1060                 remote = rcu_dereference(priv->tid_rdma.remote);
1061                 req->comp_seg = delta_psn(qp->s_psn, wqe->psn);
1062                 len = wqe->length - (req->comp_seg * remote->max_len);
1063                 rcu_read_unlock();
1064
1065                 bth2 = mask_psn(qp->s_psn);
1066                 hwords += hfi1_build_tid_rdma_write_req(qp, wqe, ohdr, &bth1,
1067                                                         &bth2, &len);
1068                 qp->s_psn = wqe->lpsn + 1;
1069                 ss = NULL;
1070                 qp->s_state = TID_OP(WRITE_REQ);
1071                 priv->pending_tid_w_resp += delta_psn(wqe->lpsn, bth2) + 1;
1072                 priv->s_tid_cur = qp->s_cur;
1073                 if (++qp->s_cur == qp->s_size)
1074                         qp->s_cur = 0;
1075                 trace_hfi1_tid_req_make_req_write(qp, 0, wqe->wr.opcode,
1076                                                   wqe->psn, wqe->lpsn, req);
1077                 break;
1078
1079         case TID_OP(READ_RESP):
1080                 if (wqe->wr.opcode != IB_WR_TID_RDMA_READ)
1081                         goto bail;
1082                 /* This is used to restart a TID read request */
1083                 req = wqe_to_tid_req(wqe);
1084                 wpriv = wqe->priv;
1085                 /*
1086                  * Back down. The field qp->s_psn has been set to the psn with
1087                  * which the request should be restart. It's OK to use division
1088                  * as this is on the retry path.
1089                  */
1090                 req->cur_seg = delta_psn(qp->s_psn, wqe->psn) / priv->pkts_ps;
1091
1092                 /*
1093                  * The following function need to be redefined to return the
1094                  * status to make sure that we find the flow. At the same
1095                  * time, we can use the req->state change to check if the
1096                  * call succeeds or not.
1097                  */
1098                 req->state = TID_REQUEST_RESEND;
1099                 hfi1_tid_rdma_restart_req(qp, wqe, &bth2);
1100                 if (req->state != TID_REQUEST_ACTIVE) {
1101                         /*
1102                          * Failed to find the flow. Release all allocated tid
1103                          * resources.
1104                          */
1105                         hfi1_kern_exp_rcv_clear_all(req);
1106                         hfi1_kern_clear_hw_flow(priv->rcd, qp);
1107
1108                         hfi1_trdma_send_complete(qp, wqe, IB_WC_LOC_QP_OP_ERR);
1109                         goto bail;
1110                 }
1111                 req->state = TID_REQUEST_RESEND;
1112                 len = min_t(u32, req->seg_len,
1113                             wqe->length - req->seg_len * req->cur_seg);
1114                 flow = &req->flows[req->flow_idx];
1115                 len -= flow->sent;
1116                 req->s_next_psn = flow->flow_state.ib_lpsn + 1;
1117                 delta = hfi1_build_tid_rdma_read_packet(wqe, ohdr, &bth1,
1118                                                         &bth2, &len);
1119                 if (delta <= 0) {
1120                         /* Wait for TID space */
1121                         goto bail;
1122                 }
1123                 hwords += delta;
1124                 ss = &wpriv->ss;
1125                 /* Check if this is the last segment */
1126                 if (req->cur_seg >= req->total_segs &&
1127                     ++qp->s_cur == qp->s_size)
1128                         qp->s_cur = 0;
1129                 qp->s_psn = req->s_next_psn;
1130                 trace_hfi1_tid_req_make_req_read(qp, 0, wqe->wr.opcode,
1131                                                  wqe->psn, wqe->lpsn, req);
1132                 break;
1133         case TID_OP(READ_REQ):
1134                 req = wqe_to_tid_req(wqe);
1135                 delta = cmp_psn(qp->s_psn, wqe->psn);
1136                 /*
1137                  * If the current WR is not TID RDMA READ, or this is the start
1138                  * of a new request, we need to change the qp->s_state so that
1139                  * the request can be set up properly.
1140                  */
1141                 if (wqe->wr.opcode != IB_WR_TID_RDMA_READ || delta == 0 ||
1142                     qp->s_cur == qp->s_tail) {
1143                         qp->s_state = OP(RDMA_READ_REQUEST);
1144                         if (delta == 0 || qp->s_cur == qp->s_tail)
1145                                 goto check_s_state;
1146                         else
1147                                 goto bail;
1148                 }
1149
1150                 /* Rate limiting */
1151                 if (qp->s_num_rd_atomic >= qp->s_max_rd_atomic) {
1152                         qp->s_flags |= RVT_S_WAIT_RDMAR;
1153                         goto bail;
1154                 }
1155
1156                 wpriv = wqe->priv;
1157                 /* Read one segment at a time */
1158                 len = min_t(u32, req->seg_len,
1159                             wqe->length - req->seg_len * req->cur_seg);
1160                 delta = hfi1_build_tid_rdma_read_req(qp, wqe, ohdr, &bth1,
1161                                                      &bth2, &len);
1162                 if (delta <= 0) {
1163                         /* Wait for TID space */
1164                         goto bail;
1165                 }
1166                 hwords += delta;
1167                 ss = &wpriv->ss;
1168                 /* Check if this is the last segment */
1169                 if (req->cur_seg >= req->total_segs &&
1170                     ++qp->s_cur == qp->s_size)
1171                         qp->s_cur = 0;
1172                 qp->s_psn = req->s_next_psn;
1173                 trace_hfi1_tid_req_make_req_read(qp, 0, wqe->wr.opcode,
1174                                                  wqe->psn, wqe->lpsn, req);
1175                 break;
1176         }
1177         qp->s_sending_hpsn = bth2;
1178         delta = delta_psn(bth2, wqe->psn);
1179         if (delta && delta % HFI1_PSN_CREDIT == 0 &&
1180             wqe->wr.opcode != IB_WR_TID_RDMA_WRITE)
1181                 bth2 |= IB_BTH_REQ_ACK;
1182         if (qp->s_flags & RVT_S_SEND_ONE) {
1183                 qp->s_flags &= ~RVT_S_SEND_ONE;
1184                 qp->s_flags |= RVT_S_WAIT_ACK;
1185                 bth2 |= IB_BTH_REQ_ACK;
1186         }
1187         qp->s_len -= len;
1188         ps->s_txreq->hdr_dwords = hwords;
1189         ps->s_txreq->sde = priv->s_sde;
1190         ps->s_txreq->ss = ss;
1191         ps->s_txreq->s_cur_size = len;
1192         hfi1_make_ruc_header(
1193                 qp,
1194                 ohdr,
1195                 bth0 | (qp->s_state << 24),
1196                 bth1,
1197                 bth2,
1198                 middle,
1199                 ps);
1200         return 1;
1201
1202 done_free_tx:
1203         hfi1_put_txreq(ps->s_txreq);
1204         ps->s_txreq = NULL;
1205         return 1;
1206
1207 bail:
1208         hfi1_put_txreq(ps->s_txreq);
1209
1210 bail_no_tx:
1211         ps->s_txreq = NULL;
1212         qp->s_flags &= ~RVT_S_BUSY;
1213         /*
1214          * If we didn't get a txreq, the QP will be woken up later to try
1215          * again. Set the flags to indicate which work item to wake
1216          * up.
1217          */
1218         iowait_set_flag(&priv->s_iowait, IOWAIT_PENDING_IB);
1219         return 0;
1220 }
1221
1222 static inline void hfi1_make_bth_aeth(struct rvt_qp *qp,
1223                                       struct ib_other_headers *ohdr,
1224                                       u32 bth0, u32 bth1)
1225 {
1226         if (qp->r_nak_state)
1227                 ohdr->u.aeth = cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
1228                                             (qp->r_nak_state <<
1229                                              IB_AETH_CREDIT_SHIFT));
1230         else
1231                 ohdr->u.aeth = rvt_compute_aeth(qp);
1232
1233         ohdr->bth[0] = cpu_to_be32(bth0);
1234         ohdr->bth[1] = cpu_to_be32(bth1 | qp->remote_qpn);
1235         ohdr->bth[2] = cpu_to_be32(mask_psn(qp->r_ack_psn));
1236 }
1237
1238 static inline void hfi1_queue_rc_ack(struct hfi1_packet *packet, bool is_fecn)
1239 {
1240         struct rvt_qp *qp = packet->qp;
1241         struct hfi1_ibport *ibp;
1242         unsigned long flags;
1243
1244         spin_lock_irqsave(&qp->s_lock, flags);
1245         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
1246                 goto unlock;
1247         ibp = rcd_to_iport(packet->rcd);
1248         this_cpu_inc(*ibp->rvp.rc_qacks);
1249         qp->s_flags |= RVT_S_ACK_PENDING | RVT_S_RESP_PENDING;
1250         qp->s_nak_state = qp->r_nak_state;
1251         qp->s_ack_psn = qp->r_ack_psn;
1252         if (is_fecn)
1253                 qp->s_flags |= RVT_S_ECN;
1254
1255         /* Schedule the send tasklet. */
1256         hfi1_schedule_send(qp);
1257 unlock:
1258         spin_unlock_irqrestore(&qp->s_lock, flags);
1259 }
1260
1261 static inline void hfi1_make_rc_ack_9B(struct hfi1_packet *packet,
1262                                        struct hfi1_opa_header *opa_hdr,
1263                                        u8 sc5, bool is_fecn,
1264                                        u64 *pbc_flags, u32 *hwords,
1265                                        u32 *nwords)
1266 {
1267         struct rvt_qp *qp = packet->qp;
1268         struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
1269         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1270         struct ib_header *hdr = &opa_hdr->ibh;
1271         struct ib_other_headers *ohdr;
1272         u16 lrh0 = HFI1_LRH_BTH;
1273         u16 pkey;
1274         u32 bth0, bth1;
1275
1276         opa_hdr->hdr_type = HFI1_PKT_TYPE_9B;
1277         ohdr = &hdr->u.oth;
1278         /* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4 */
1279         *hwords = 6;
1280
1281         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
1282                 *hwords += hfi1_make_grh(ibp, &hdr->u.l.grh,
1283                                          rdma_ah_read_grh(&qp->remote_ah_attr),
1284                                          *hwords - 2, SIZE_OF_CRC);
1285                 ohdr = &hdr->u.l.oth;
1286                 lrh0 = HFI1_LRH_GRH;
1287         }
1288         /* set PBC_DC_INFO bit (aka SC[4]) in pbc_flags */
1289         *pbc_flags |= ((!!(sc5 & 0x10)) << PBC_DC_INFO_SHIFT);
1290
1291         /* read pkey_index w/o lock (its atomic) */
1292         pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
1293
1294         lrh0 |= (sc5 & IB_SC_MASK) << IB_SC_SHIFT |
1295                 (rdma_ah_get_sl(&qp->remote_ah_attr) & IB_SL_MASK) <<
1296                         IB_SL_SHIFT;
1297
1298         hfi1_make_ib_hdr(hdr, lrh0, *hwords + SIZE_OF_CRC,
1299                          opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr), 9B),
1300                          ppd->lid | rdma_ah_get_path_bits(&qp->remote_ah_attr));
1301
1302         bth0 = pkey | (OP(ACKNOWLEDGE) << 24);
1303         if (qp->s_mig_state == IB_MIG_MIGRATED)
1304                 bth0 |= IB_BTH_MIG_REQ;
1305         bth1 = (!!is_fecn) << IB_BECN_SHIFT;
1306         /*
1307          * Inline ACKs go out without the use of the Verbs send engine, so
1308          * we need to set the STL Verbs Extended bit here
1309          */
1310         bth1 |= HFI1_CAP_IS_KSET(OPFN) << IB_BTHE_E_SHIFT;
1311         hfi1_make_bth_aeth(qp, ohdr, bth0, bth1);
1312 }
1313
1314 static inline void hfi1_make_rc_ack_16B(struct hfi1_packet *packet,
1315                                         struct hfi1_opa_header *opa_hdr,
1316                                         u8 sc5, bool is_fecn,
1317                                         u64 *pbc_flags, u32 *hwords,
1318                                         u32 *nwords)
1319 {
1320         struct rvt_qp *qp = packet->qp;
1321         struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
1322         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1323         struct hfi1_16b_header *hdr = &opa_hdr->opah;
1324         struct ib_other_headers *ohdr;
1325         u32 bth0, bth1 = 0;
1326         u16 len, pkey;
1327         bool becn = is_fecn;
1328         u8 l4 = OPA_16B_L4_IB_LOCAL;
1329         u8 extra_bytes;
1330
1331         opa_hdr->hdr_type = HFI1_PKT_TYPE_16B;
1332         ohdr = &hdr->u.oth;
1333         /* header size in 32-bit words 16B LRH+BTH+AETH = (16+12+4)/4 */
1334         *hwords = 8;
1335         extra_bytes = hfi1_get_16b_padding(*hwords << 2, 0);
1336         *nwords = SIZE_OF_CRC + ((extra_bytes + SIZE_OF_LT) >> 2);
1337
1338         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
1339             hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))) {
1340                 *hwords += hfi1_make_grh(ibp, &hdr->u.l.grh,
1341                                          rdma_ah_read_grh(&qp->remote_ah_attr),
1342                                          *hwords - 4, *nwords);
1343                 ohdr = &hdr->u.l.oth;
1344                 l4 = OPA_16B_L4_IB_GLOBAL;
1345         }
1346         *pbc_flags |= PBC_PACKET_BYPASS | PBC_INSERT_BYPASS_ICRC;
1347
1348         /* read pkey_index w/o lock (its atomic) */
1349         pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
1350
1351         /* Convert dwords to flits */
1352         len = (*hwords + *nwords) >> 1;
1353
1354         hfi1_make_16b_hdr(hdr, ppd->lid |
1355                           (rdma_ah_get_path_bits(&qp->remote_ah_attr) &
1356                           ((1 << ppd->lmc) - 1)),
1357                           opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr),
1358                                       16B), len, pkey, becn, 0, l4, sc5);
1359
1360         bth0 = pkey | (OP(ACKNOWLEDGE) << 24);
1361         bth0 |= extra_bytes << 20;
1362         if (qp->s_mig_state == IB_MIG_MIGRATED)
1363                 bth1 = OPA_BTH_MIG_REQ;
1364         hfi1_make_bth_aeth(qp, ohdr, bth0, bth1);
1365 }
1366
1367 typedef void (*hfi1_make_rc_ack)(struct hfi1_packet *packet,
1368                                  struct hfi1_opa_header *opa_hdr,
1369                                  u8 sc5, bool is_fecn,
1370                                  u64 *pbc_flags, u32 *hwords,
1371                                  u32 *nwords);
1372
1373 /* We support only two types - 9B and 16B for now */
1374 static const hfi1_make_rc_ack hfi1_make_rc_ack_tbl[2] = {
1375         [HFI1_PKT_TYPE_9B] = &hfi1_make_rc_ack_9B,
1376         [HFI1_PKT_TYPE_16B] = &hfi1_make_rc_ack_16B
1377 };
1378
1379 /**
1380  * hfi1_send_rc_ack - Construct an ACK packet and send it
1381  * @qp: a pointer to the QP
1382  *
1383  * This is called from hfi1_rc_rcv() and handle_receive_interrupt().
1384  * Note that RDMA reads and atomics are handled in the
1385  * send side QP state and send engine.
1386  */
1387 void hfi1_send_rc_ack(struct hfi1_packet *packet, bool is_fecn)
1388 {
1389         struct hfi1_ctxtdata *rcd = packet->rcd;
1390         struct rvt_qp *qp = packet->qp;
1391         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
1392         struct hfi1_qp_priv *priv = qp->priv;
1393         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1394         u8 sc5 = ibp->sl_to_sc[rdma_ah_get_sl(&qp->remote_ah_attr)];
1395         u64 pbc, pbc_flags = 0;
1396         u32 hwords = 0;
1397         u32 nwords = 0;
1398         u32 plen;
1399         struct pio_buf *pbuf;
1400         struct hfi1_opa_header opa_hdr;
1401
1402         /* clear the defer count */
1403         qp->r_adefered = 0;
1404
1405         /* Don't send ACK or NAK if a RDMA read or atomic is pending. */
1406         if (qp->s_flags & RVT_S_RESP_PENDING) {
1407                 hfi1_queue_rc_ack(packet, is_fecn);
1408                 return;
1409         }
1410
1411         /* Ensure s_rdma_ack_cnt changes are committed */
1412         if (qp->s_rdma_ack_cnt) {
1413                 hfi1_queue_rc_ack(packet, is_fecn);
1414                 return;
1415         }
1416
1417         /* Don't try to send ACKs if the link isn't ACTIVE */
1418         if (driver_lstate(ppd) != IB_PORT_ACTIVE)
1419                 return;
1420
1421         /* Make the appropriate header */
1422         hfi1_make_rc_ack_tbl[priv->hdr_type](packet, &opa_hdr, sc5, is_fecn,
1423                                              &pbc_flags, &hwords, &nwords);
1424
1425         plen = 2 /* PBC */ + hwords + nwords;
1426         pbc = create_pbc(ppd, pbc_flags, qp->srate_mbps,
1427                          sc_to_vlt(ppd->dd, sc5), plen);
1428         pbuf = sc_buffer_alloc(rcd->sc, plen, NULL, NULL);
1429         if (IS_ERR_OR_NULL(pbuf)) {
1430                 /*
1431                  * We have no room to send at the moment.  Pass
1432                  * responsibility for sending the ACK to the send engine
1433                  * so that when enough buffer space becomes available,
1434                  * the ACK is sent ahead of other outgoing packets.
1435                  */
1436                 hfi1_queue_rc_ack(packet, is_fecn);
1437                 return;
1438         }
1439         trace_ack_output_ibhdr(dd_from_ibdev(qp->ibqp.device),
1440                                &opa_hdr, ib_is_sc5(sc5));
1441
1442         /* write the pbc and data */
1443         ppd->dd->pio_inline_send(ppd->dd, pbuf, pbc,
1444                                  (priv->hdr_type == HFI1_PKT_TYPE_9B ?
1445                                  (void *)&opa_hdr.ibh :
1446                                  (void *)&opa_hdr.opah), hwords);
1447         return;
1448 }
1449
1450 /**
1451  * update_num_rd_atomic - update the qp->s_num_rd_atomic
1452  * @qp: the QP
1453  * @psn: the packet sequence number to restart at
1454  * @wqe: the wqe
1455  *
1456  * This is called from reset_psn() to update qp->s_num_rd_atomic
1457  * for the current wqe.
1458  * Called at interrupt level with the QP s_lock held.
1459  */
1460 static void update_num_rd_atomic(struct rvt_qp *qp, u32 psn,
1461                                  struct rvt_swqe *wqe)
1462 {
1463         u32 opcode = wqe->wr.opcode;
1464
1465         if (opcode == IB_WR_RDMA_READ ||
1466             opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1467             opcode == IB_WR_ATOMIC_FETCH_AND_ADD) {
1468                 qp->s_num_rd_atomic++;
1469         } else if (opcode == IB_WR_TID_RDMA_READ) {
1470                 struct tid_rdma_request *req = wqe_to_tid_req(wqe);
1471                 struct hfi1_qp_priv *priv = qp->priv;
1472
1473                 if (cmp_psn(psn, wqe->lpsn) <= 0) {
1474                         u32 cur_seg;
1475
1476                         cur_seg = (psn - wqe->psn) / priv->pkts_ps;
1477                         req->ack_pending = cur_seg - req->comp_seg;
1478                         priv->pending_tid_r_segs += req->ack_pending;
1479                         qp->s_num_rd_atomic += req->ack_pending;
1480                         trace_hfi1_tid_req_update_num_rd_atomic(qp, 0,
1481                                                                 wqe->wr.opcode,
1482                                                                 wqe->psn,
1483                                                                 wqe->lpsn,
1484                                                                 req);
1485                 } else {
1486                         priv->pending_tid_r_segs += req->total_segs;
1487                         qp->s_num_rd_atomic += req->total_segs;
1488                 }
1489         }
1490 }
1491
1492 /**
1493  * reset_psn - reset the QP state to send starting from PSN
1494  * @qp: the QP
1495  * @psn: the packet sequence number to restart at
1496  *
1497  * This is called from hfi1_rc_rcv() to process an incoming RC ACK
1498  * for the given QP.
1499  * Called at interrupt level with the QP s_lock held.
1500  */
1501 static void reset_psn(struct rvt_qp *qp, u32 psn)
1502 {
1503         u32 n = qp->s_acked;
1504         struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, n);
1505         u32 opcode;
1506         struct hfi1_qp_priv *priv = qp->priv;
1507
1508         lockdep_assert_held(&qp->s_lock);
1509         qp->s_cur = n;
1510         priv->pending_tid_r_segs = 0;
1511         priv->pending_tid_w_resp = 0;
1512         qp->s_num_rd_atomic = 0;
1513
1514         /*
1515          * If we are starting the request from the beginning,
1516          * let the normal send code handle initialization.
1517          */
1518         if (cmp_psn(psn, wqe->psn) <= 0) {
1519                 qp->s_state = OP(SEND_LAST);
1520                 goto done;
1521         }
1522         update_num_rd_atomic(qp, psn, wqe);
1523
1524         /* Find the work request opcode corresponding to the given PSN. */
1525         for (;;) {
1526                 int diff;
1527
1528                 if (++n == qp->s_size)
1529                         n = 0;
1530                 if (n == qp->s_tail)
1531                         break;
1532                 wqe = rvt_get_swqe_ptr(qp, n);
1533                 diff = cmp_psn(psn, wqe->psn);
1534                 if (diff < 0) {
1535                         /* Point wqe back to the previous one*/
1536                         wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
1537                         break;
1538                 }
1539                 qp->s_cur = n;
1540                 /*
1541                  * If we are starting the request from the beginning,
1542                  * let the normal send code handle initialization.
1543                  */
1544                 if (diff == 0) {
1545                         qp->s_state = OP(SEND_LAST);
1546                         goto done;
1547                 }
1548
1549                 update_num_rd_atomic(qp, psn, wqe);
1550         }
1551         opcode = wqe->wr.opcode;
1552
1553         /*
1554          * Set the state to restart in the middle of a request.
1555          * Don't change the s_sge, s_cur_sge, or s_cur_size.
1556          * See hfi1_make_rc_req().
1557          */
1558         switch (opcode) {
1559         case IB_WR_SEND:
1560         case IB_WR_SEND_WITH_IMM:
1561                 qp->s_state = OP(RDMA_READ_RESPONSE_FIRST);
1562                 break;
1563
1564         case IB_WR_RDMA_WRITE:
1565         case IB_WR_RDMA_WRITE_WITH_IMM:
1566                 qp->s_state = OP(RDMA_READ_RESPONSE_LAST);
1567                 break;
1568
1569         case IB_WR_TID_RDMA_WRITE:
1570                 qp->s_state = TID_OP(WRITE_RESP);
1571                 break;
1572
1573         case IB_WR_RDMA_READ:
1574                 qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE);
1575                 break;
1576
1577         case IB_WR_TID_RDMA_READ:
1578                 qp->s_state = TID_OP(READ_RESP);
1579                 break;
1580
1581         default:
1582                 /*
1583                  * This case shouldn't happen since its only
1584                  * one PSN per req.
1585                  */
1586                 qp->s_state = OP(SEND_LAST);
1587         }
1588 done:
1589         priv->s_flags &= ~HFI1_S_TID_WAIT_INTERLCK;
1590         qp->s_psn = psn;
1591         /*
1592          * Set RVT_S_WAIT_PSN as rc_complete() may start the timer
1593          * asynchronously before the send engine can get scheduled.
1594          * Doing it in hfi1_make_rc_req() is too late.
1595          */
1596         if ((cmp_psn(qp->s_psn, qp->s_sending_hpsn) <= 0) &&
1597             (cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0))
1598                 qp->s_flags |= RVT_S_WAIT_PSN;
1599         qp->s_flags &= ~HFI1_S_AHG_VALID;
1600         trace_hfi1_sender_reset_psn(qp);
1601 }
1602
1603 /*
1604  * Back up requester to resend the last un-ACKed request.
1605  * The QP r_lock and s_lock should be held and interrupts disabled.
1606  */
1607 void hfi1_restart_rc(struct rvt_qp *qp, u32 psn, int wait)
1608 {
1609         struct hfi1_qp_priv *priv = qp->priv;
1610         struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1611         struct hfi1_ibport *ibp;
1612
1613         lockdep_assert_held(&qp->r_lock);
1614         lockdep_assert_held(&qp->s_lock);
1615         trace_hfi1_sender_restart_rc(qp);
1616         if (qp->s_retry == 0) {
1617                 if (qp->s_mig_state == IB_MIG_ARMED) {
1618                         hfi1_migrate_qp(qp);
1619                         qp->s_retry = qp->s_retry_cnt;
1620                 } else if (qp->s_last == qp->s_acked) {
1621                         /*
1622                          * We need special handling for the OPFN request WQEs as
1623                          * they are not allowed to generate real user errors
1624                          */
1625                         if (wqe->wr.opcode == IB_WR_OPFN) {
1626                                 struct hfi1_ibport *ibp =
1627                                         to_iport(qp->ibqp.device, qp->port_num);
1628                                 /*
1629                                  * Call opfn_conn_reply() with capcode and
1630                                  * remaining data as 0 to close out the
1631                                  * current request
1632                                  */
1633                                 opfn_conn_reply(qp, priv->opfn.curr);
1634                                 wqe = do_rc_completion(qp, wqe, ibp);
1635                                 qp->s_flags &= ~RVT_S_WAIT_ACK;
1636                         } else {
1637                                 trace_hfi1_tid_write_sender_restart_rc(qp, 0);
1638                                 if (wqe->wr.opcode == IB_WR_TID_RDMA_READ) {
1639                                         struct tid_rdma_request *req;
1640
1641                                         req = wqe_to_tid_req(wqe);
1642                                         hfi1_kern_exp_rcv_clear_all(req);
1643                                         hfi1_kern_clear_hw_flow(priv->rcd, qp);
1644                                 }
1645
1646                                 hfi1_trdma_send_complete(qp, wqe,
1647                                                          IB_WC_RETRY_EXC_ERR);
1648                                 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1649                         }
1650                         return;
1651                 } else { /* need to handle delayed completion */
1652                         return;
1653                 }
1654         } else {
1655                 qp->s_retry--;
1656         }
1657
1658         ibp = to_iport(qp->ibqp.device, qp->port_num);
1659         if (wqe->wr.opcode == IB_WR_RDMA_READ ||
1660             wqe->wr.opcode == IB_WR_TID_RDMA_READ)
1661                 ibp->rvp.n_rc_resends++;
1662         else
1663                 ibp->rvp.n_rc_resends += delta_psn(qp->s_psn, psn);
1664
1665         qp->s_flags &= ~(RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR |
1666                          RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_PSN |
1667                          RVT_S_WAIT_ACK | HFI1_S_WAIT_TID_RESP);
1668         if (wait)
1669                 qp->s_flags |= RVT_S_SEND_ONE;
1670         reset_psn(qp, psn);
1671 }
1672
1673 /*
1674  * Set qp->s_sending_psn to the next PSN after the given one.
1675  * This would be psn+1 except when RDMA reads or TID RDMA ops
1676  * are present.
1677  */
1678 static void reset_sending_psn(struct rvt_qp *qp, u32 psn)
1679 {
1680         struct rvt_swqe *wqe;
1681         u32 n = qp->s_last;
1682
1683         lockdep_assert_held(&qp->s_lock);
1684         /* Find the work request corresponding to the given PSN. */
1685         for (;;) {
1686                 wqe = rvt_get_swqe_ptr(qp, n);
1687                 if (cmp_psn(psn, wqe->lpsn) <= 0) {
1688                         if (wqe->wr.opcode == IB_WR_RDMA_READ ||
1689                             wqe->wr.opcode == IB_WR_TID_RDMA_READ ||
1690                             wqe->wr.opcode == IB_WR_TID_RDMA_WRITE)
1691                                 qp->s_sending_psn = wqe->lpsn + 1;
1692                         else
1693                                 qp->s_sending_psn = psn + 1;
1694                         break;
1695                 }
1696                 if (++n == qp->s_size)
1697                         n = 0;
1698                 if (n == qp->s_tail)
1699                         break;
1700         }
1701 }
1702
1703 /**
1704  * hfi1_rc_verbs_aborted - handle abort status
1705  * @qp: the QP
1706  * @opah: the opa header
1707  *
1708  * This code modifies both ACK bit in BTH[2]
1709  * and the s_flags to go into send one mode.
1710  *
1711  * This serves to throttle the send engine to only
1712  * send a single packet in the likely case the
1713  * a link has gone down.
1714  */
1715 void hfi1_rc_verbs_aborted(struct rvt_qp *qp, struct hfi1_opa_header *opah)
1716 {
1717         struct ib_other_headers *ohdr = hfi1_get_rc_ohdr(opah);
1718         u8 opcode = ib_bth_get_opcode(ohdr);
1719         u32 psn;
1720
1721         /* ignore responses */
1722         if ((opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1723              opcode <= OP(ATOMIC_ACKNOWLEDGE)) ||
1724             opcode == TID_OP(READ_RESP) ||
1725             opcode == TID_OP(WRITE_RESP))
1726                 return;
1727
1728         psn = ib_bth_get_psn(ohdr) | IB_BTH_REQ_ACK;
1729         ohdr->bth[2] = cpu_to_be32(psn);
1730         qp->s_flags |= RVT_S_SEND_ONE;
1731 }
1732
1733 /*
1734  * This should be called with the QP s_lock held and interrupts disabled.
1735  */
1736 void hfi1_rc_send_complete(struct rvt_qp *qp, struct hfi1_opa_header *opah)
1737 {
1738         struct ib_other_headers *ohdr;
1739         struct hfi1_qp_priv *priv = qp->priv;
1740         struct rvt_swqe *wqe;
1741         u32 opcode, head, tail;
1742         u32 psn;
1743         struct tid_rdma_request *req;
1744
1745         lockdep_assert_held(&qp->s_lock);
1746         if (!(ib_rvt_state_ops[qp->state] & RVT_SEND_OR_FLUSH_OR_RECV_OK))
1747                 return;
1748
1749         ohdr = hfi1_get_rc_ohdr(opah);
1750         opcode = ib_bth_get_opcode(ohdr);
1751         if ((opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1752              opcode <= OP(ATOMIC_ACKNOWLEDGE)) ||
1753             opcode == TID_OP(READ_RESP) ||
1754             opcode == TID_OP(WRITE_RESP)) {
1755                 WARN_ON(!qp->s_rdma_ack_cnt);
1756                 qp->s_rdma_ack_cnt--;
1757                 return;
1758         }
1759
1760         psn = ib_bth_get_psn(ohdr);
1761         /*
1762          * Don't attempt to reset the sending PSN for packets in the
1763          * KDETH PSN space since the PSN does not match anything.
1764          */
1765         if (opcode != TID_OP(WRITE_DATA) &&
1766             opcode != TID_OP(WRITE_DATA_LAST) &&
1767             opcode != TID_OP(ACK) && opcode != TID_OP(RESYNC))
1768                 reset_sending_psn(qp, psn);
1769
1770         /* Handle TID RDMA WRITE packets differently */
1771         if (opcode >= TID_OP(WRITE_REQ) &&
1772             opcode <= TID_OP(WRITE_DATA_LAST)) {
1773                 head = priv->s_tid_head;
1774                 tail = priv->s_tid_cur;
1775                 /*
1776                  * s_tid_cur is set to s_tid_head in the case, where
1777                  * a new TID RDMA request is being started and all
1778                  * previous ones have been completed.
1779                  * Therefore, we need to do a secondary check in order
1780                  * to properly determine whether we should start the
1781                  * RC timer.
1782                  */
1783                 wqe = rvt_get_swqe_ptr(qp, tail);
1784                 req = wqe_to_tid_req(wqe);
1785                 if (head == tail && req->comp_seg < req->total_segs) {
1786                         if (tail == 0)
1787                                 tail = qp->s_size - 1;
1788                         else
1789                                 tail -= 1;
1790                 }
1791         } else {
1792                 head = qp->s_tail;
1793                 tail = qp->s_acked;
1794         }
1795
1796         /*
1797          * Start timer after a packet requesting an ACK has been sent and
1798          * there are still requests that haven't been acked.
1799          */
1800         if ((psn & IB_BTH_REQ_ACK) && tail != head &&
1801             opcode != TID_OP(WRITE_DATA) && opcode != TID_OP(WRITE_DATA_LAST) &&
1802             opcode != TID_OP(RESYNC) &&
1803             !(qp->s_flags &
1804               (RVT_S_TIMER | RVT_S_WAIT_RNR | RVT_S_WAIT_PSN)) &&
1805             (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) {
1806                 if (opcode == TID_OP(READ_REQ))
1807                         rvt_add_retry_timer_ext(qp, priv->timeout_shift);
1808                 else
1809                         rvt_add_retry_timer(qp);
1810         }
1811
1812         /* Start TID RDMA ACK timer */
1813         if ((opcode == TID_OP(WRITE_DATA) ||
1814              opcode == TID_OP(WRITE_DATA_LAST) ||
1815              opcode == TID_OP(RESYNC)) &&
1816             (psn & IB_BTH_REQ_ACK) &&
1817             !(priv->s_flags & HFI1_S_TID_RETRY_TIMER) &&
1818             (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) {
1819                 /*
1820                  * The TID RDMA ACK packet could be received before this
1821                  * function is called. Therefore, add the timer only if TID
1822                  * RDMA ACK packets are actually pending.
1823                  */
1824                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1825                 req = wqe_to_tid_req(wqe);
1826                 if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE &&
1827                     req->ack_seg < req->cur_seg)
1828                         hfi1_add_tid_retry_timer(qp);
1829         }
1830
1831         while (qp->s_last != qp->s_acked) {
1832                 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
1833                 if (cmp_psn(wqe->lpsn, qp->s_sending_psn) >= 0 &&
1834                     cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)
1835                         break;
1836                 trdma_clean_swqe(qp, wqe);
1837                 trace_hfi1_qp_send_completion(qp, wqe, qp->s_last);
1838                 rvt_qp_complete_swqe(qp,
1839                                      wqe,
1840                                      ib_hfi1_wc_opcode[wqe->wr.opcode],
1841                                      IB_WC_SUCCESS);
1842         }
1843         /*
1844          * If we were waiting for sends to complete before re-sending,
1845          * and they are now complete, restart sending.
1846          */
1847         trace_hfi1_sendcomplete(qp, psn);
1848         if (qp->s_flags & RVT_S_WAIT_PSN &&
1849             cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
1850                 qp->s_flags &= ~RVT_S_WAIT_PSN;
1851                 qp->s_sending_psn = qp->s_psn;
1852                 qp->s_sending_hpsn = qp->s_psn - 1;
1853                 hfi1_schedule_send(qp);
1854         }
1855 }
1856
1857 static inline void update_last_psn(struct rvt_qp *qp, u32 psn)
1858 {
1859         qp->s_last_psn = psn;
1860 }
1861
1862 /*
1863  * Generate a SWQE completion.
1864  * This is similar to hfi1_send_complete but has to check to be sure
1865  * that the SGEs are not being referenced if the SWQE is being resent.
1866  */
1867 struct rvt_swqe *do_rc_completion(struct rvt_qp *qp,
1868                                   struct rvt_swqe *wqe,
1869                                   struct hfi1_ibport *ibp)
1870 {
1871         struct hfi1_qp_priv *priv = qp->priv;
1872
1873         lockdep_assert_held(&qp->s_lock);
1874         /*
1875          * Don't decrement refcount and don't generate a
1876          * completion if the SWQE is being resent until the send
1877          * is finished.
1878          */
1879         trace_hfi1_rc_completion(qp, wqe->lpsn);
1880         if (cmp_psn(wqe->lpsn, qp->s_sending_psn) < 0 ||
1881             cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
1882                 trdma_clean_swqe(qp, wqe);
1883                 trace_hfi1_qp_send_completion(qp, wqe, qp->s_last);
1884                 rvt_qp_complete_swqe(qp,
1885                                      wqe,
1886                                      ib_hfi1_wc_opcode[wqe->wr.opcode],
1887                                      IB_WC_SUCCESS);
1888         } else {
1889                 struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1890
1891                 this_cpu_inc(*ibp->rvp.rc_delayed_comp);
1892                 /*
1893                  * If send progress not running attempt to progress
1894                  * SDMA queue.
1895                  */
1896                 if (ppd->dd->flags & HFI1_HAS_SEND_DMA) {
1897                         struct sdma_engine *engine;
1898                         u8 sl = rdma_ah_get_sl(&qp->remote_ah_attr);
1899                         u8 sc5;
1900
1901                         /* For now use sc to find engine */
1902                         sc5 = ibp->sl_to_sc[sl];
1903                         engine = qp_to_sdma_engine(qp, sc5);
1904                         sdma_engine_progress_schedule(engine);
1905                 }
1906         }
1907
1908         qp->s_retry = qp->s_retry_cnt;
1909         /*
1910          * Don't update the last PSN if the request being completed is
1911          * a TID RDMA WRITE request.
1912          * Completion of the TID RDMA WRITE requests are done by the
1913          * TID RDMA ACKs and as such could be for a request that has
1914          * already been ACKed as far as the IB state machine is
1915          * concerned.
1916          */
1917         if (wqe->wr.opcode != IB_WR_TID_RDMA_WRITE)
1918                 update_last_psn(qp, wqe->lpsn);
1919
1920         /*
1921          * If we are completing a request which is in the process of
1922          * being resent, we can stop re-sending it since we know the
1923          * responder has already seen it.
1924          */
1925         if (qp->s_acked == qp->s_cur) {
1926                 if (++qp->s_cur >= qp->s_size)
1927                         qp->s_cur = 0;
1928                 qp->s_acked = qp->s_cur;
1929                 wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
1930                 if (qp->s_acked != qp->s_tail) {
1931                         qp->s_state = OP(SEND_LAST);
1932                         qp->s_psn = wqe->psn;
1933                 }
1934         } else {
1935                 if (++qp->s_acked >= qp->s_size)
1936                         qp->s_acked = 0;
1937                 if (qp->state == IB_QPS_SQD && qp->s_acked == qp->s_cur)
1938                         qp->s_draining = 0;
1939                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1940         }
1941         if (priv->s_flags & HFI1_S_TID_WAIT_INTERLCK) {
1942                 priv->s_flags &= ~HFI1_S_TID_WAIT_INTERLCK;
1943                 hfi1_schedule_send(qp);
1944         }
1945         return wqe;
1946 }
1947
1948 static void set_restart_qp(struct rvt_qp *qp, struct hfi1_ctxtdata *rcd)
1949 {
1950         /* Retry this request. */
1951         if (!(qp->r_flags & RVT_R_RDMAR_SEQ)) {
1952                 qp->r_flags |= RVT_R_RDMAR_SEQ;
1953                 hfi1_restart_rc(qp, qp->s_last_psn + 1, 0);
1954                 if (list_empty(&qp->rspwait)) {
1955                         qp->r_flags |= RVT_R_RSP_SEND;
1956                         rvt_get_qp(qp);
1957                         list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
1958                 }
1959         }
1960 }
1961
1962 /**
1963  * update_qp_retry_state - Update qp retry state.
1964  * @qp: the QP
1965  * @psn: the packet sequence number of the TID RDMA WRITE RESP.
1966  * @spsn:  The start psn for the given TID RDMA WRITE swqe.
1967  * @lpsn:  The last psn for the given TID RDMA WRITE swqe.
1968  *
1969  * This function is called to update the qp retry state upon
1970  * receiving a TID WRITE RESP after the qp is scheduled to retry
1971  * a request.
1972  */
1973 static void update_qp_retry_state(struct rvt_qp *qp, u32 psn, u32 spsn,
1974                                   u32 lpsn)
1975 {
1976         struct hfi1_qp_priv *qpriv = qp->priv;
1977
1978         qp->s_psn = psn + 1;
1979         /*
1980          * If this is the first TID RDMA WRITE RESP packet for the current
1981          * request, change the s_state so that the retry will be processed
1982          * correctly. Similarly, if this is the last TID RDMA WRITE RESP
1983          * packet, change the s_state and advance the s_cur.
1984          */
1985         if (cmp_psn(psn, lpsn) >= 0) {
1986                 qp->s_cur = qpriv->s_tid_cur + 1;
1987                 if (qp->s_cur >= qp->s_size)
1988                         qp->s_cur = 0;
1989                 qp->s_state = TID_OP(WRITE_REQ);
1990         } else  if (!cmp_psn(psn, spsn)) {
1991                 qp->s_cur = qpriv->s_tid_cur;
1992                 qp->s_state = TID_OP(WRITE_RESP);
1993         }
1994 }
1995
1996 /**
1997  * do_rc_ack - process an incoming RC ACK
1998  * @qp: the QP the ACK came in on
1999  * @psn: the packet sequence number of the ACK
2000  * @opcode: the opcode of the request that resulted in the ACK
2001  *
2002  * This is called from rc_rcv_resp() to process an incoming RC ACK
2003  * for the given QP.
2004  * May be called at interrupt level, with the QP s_lock held.
2005  * Returns 1 if OK, 0 if current operation should be aborted (NAK).
2006  */
2007 int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
2008               u64 val, struct hfi1_ctxtdata *rcd)
2009 {
2010         struct hfi1_ibport *ibp;
2011         enum ib_wc_status status;
2012         struct hfi1_qp_priv *qpriv = qp->priv;
2013         struct rvt_swqe *wqe;
2014         int ret = 0;
2015         u32 ack_psn;
2016         int diff;
2017         struct rvt_dev_info *rdi;
2018
2019         lockdep_assert_held(&qp->s_lock);
2020         /*
2021          * Note that NAKs implicitly ACK outstanding SEND and RDMA write
2022          * requests and implicitly NAK RDMA read and atomic requests issued
2023          * before the NAK'ed request.  The MSN won't include the NAK'ed
2024          * request but will include an ACK'ed request(s).
2025          */
2026         ack_psn = psn;
2027         if (aeth >> IB_AETH_NAK_SHIFT)
2028                 ack_psn--;
2029         wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2030         ibp = rcd_to_iport(rcd);
2031
2032         /*
2033          * The MSN might be for a later WQE than the PSN indicates so
2034          * only complete WQEs that the PSN finishes.
2035          */
2036         while ((diff = delta_psn(ack_psn, wqe->lpsn)) >= 0) {
2037                 /*
2038                  * RDMA_READ_RESPONSE_ONLY is a special case since
2039                  * we want to generate completion events for everything
2040                  * before the RDMA read, copy the data, then generate
2041                  * the completion for the read.
2042                  */
2043                 if (wqe->wr.opcode == IB_WR_RDMA_READ &&
2044                     opcode == OP(RDMA_READ_RESPONSE_ONLY) &&
2045                     diff == 0) {
2046                         ret = 1;
2047                         goto bail_stop;
2048                 }
2049                 /*
2050                  * If this request is a RDMA read or atomic, and the ACK is
2051                  * for a later operation, this ACK NAKs the RDMA read or
2052                  * atomic.  In other words, only a RDMA_READ_LAST or ONLY
2053                  * can ACK a RDMA read and likewise for atomic ops.  Note
2054                  * that the NAK case can only happen if relaxed ordering is
2055                  * used and requests are sent after an RDMA read or atomic
2056                  * is sent but before the response is received.
2057                  */
2058                 if ((wqe->wr.opcode == IB_WR_RDMA_READ &&
2059                      (opcode != OP(RDMA_READ_RESPONSE_LAST) || diff != 0)) ||
2060                     (wqe->wr.opcode == IB_WR_TID_RDMA_READ &&
2061                      (opcode != TID_OP(READ_RESP) || diff != 0)) ||
2062                     ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2063                       wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) &&
2064                      (opcode != OP(ATOMIC_ACKNOWLEDGE) || diff != 0)) ||
2065                     (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE &&
2066                      (delta_psn(psn, qp->s_last_psn) != 1))) {
2067                         set_restart_qp(qp, rcd);
2068                         /*
2069                          * No need to process the ACK/NAK since we are
2070                          * restarting an earlier request.
2071                          */
2072                         goto bail_stop;
2073                 }
2074                 if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2075                     wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) {
2076                         u64 *vaddr = wqe->sg_list[0].vaddr;
2077                         *vaddr = val;
2078                 }
2079                 if (wqe->wr.opcode == IB_WR_OPFN)
2080                         opfn_conn_reply(qp, val);
2081
2082                 if (qp->s_num_rd_atomic &&
2083                     (wqe->wr.opcode == IB_WR_RDMA_READ ||
2084                      wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2085                      wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)) {
2086                         qp->s_num_rd_atomic--;
2087                         /* Restart sending task if fence is complete */
2088                         if ((qp->s_flags & RVT_S_WAIT_FENCE) &&
2089                             !qp->s_num_rd_atomic) {
2090                                 qp->s_flags &= ~(RVT_S_WAIT_FENCE |
2091                                                  RVT_S_WAIT_ACK);
2092                                 hfi1_schedule_send(qp);
2093                         } else if (qp->s_flags & RVT_S_WAIT_RDMAR) {
2094                                 qp->s_flags &= ~(RVT_S_WAIT_RDMAR |
2095                                                  RVT_S_WAIT_ACK);
2096                                 hfi1_schedule_send(qp);
2097                         }
2098                 }
2099
2100                 /*
2101                  * TID RDMA WRITE requests will be completed by the TID RDMA
2102                  * ACK packet handler (see tid_rdma.c).
2103                  */
2104                 if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE)
2105                         break;
2106
2107                 wqe = do_rc_completion(qp, wqe, ibp);
2108                 if (qp->s_acked == qp->s_tail)
2109                         break;
2110         }
2111
2112         trace_hfi1_rc_ack_do(qp, aeth, psn, wqe);
2113         trace_hfi1_sender_do_rc_ack(qp);
2114         switch (aeth >> IB_AETH_NAK_SHIFT) {
2115         case 0:         /* ACK */
2116                 this_cpu_inc(*ibp->rvp.rc_acks);
2117                 if (wqe->wr.opcode == IB_WR_TID_RDMA_READ) {
2118                         if (wqe_to_tid_req(wqe)->ack_pending)
2119                                 rvt_mod_retry_timer_ext(qp,
2120                                                         qpriv->timeout_shift);
2121                         else
2122                                 rvt_stop_rc_timers(qp);
2123                 } else if (qp->s_acked != qp->s_tail) {
2124                         struct rvt_swqe *__w = NULL;
2125
2126                         if (qpriv->s_tid_cur != HFI1_QP_WQE_INVALID)
2127                                 __w = rvt_get_swqe_ptr(qp, qpriv->s_tid_cur);
2128
2129                         /*
2130                          * Stop timers if we've received all of the TID RDMA
2131                          * WRITE * responses.
2132                          */
2133                         if (__w && __w->wr.opcode == IB_WR_TID_RDMA_WRITE &&
2134                             opcode == TID_OP(WRITE_RESP)) {
2135                                 /*
2136                                  * Normally, the loop above would correctly
2137                                  * process all WQEs from s_acked onward and
2138                                  * either complete them or check for correct
2139                                  * PSN sequencing.
2140                                  * However, for TID RDMA, due to pipelining,
2141                                  * the response may not be for the request at
2142                                  * s_acked so the above look would just be
2143                                  * skipped. This does not allow for checking
2144                                  * the PSN sequencing. It has to be done
2145                                  * separately.
2146                                  */
2147                                 if (cmp_psn(psn, qp->s_last_psn + 1)) {
2148                                         set_restart_qp(qp, rcd);
2149                                         goto bail_stop;
2150                                 }
2151                                 /*
2152                                  * If the psn is being resent, stop the
2153                                  * resending.
2154                                  */
2155                                 if (qp->s_cur != qp->s_tail &&
2156                                     cmp_psn(qp->s_psn, psn) <= 0)
2157                                         update_qp_retry_state(qp, psn,
2158                                                               __w->psn,
2159                                                               __w->lpsn);
2160                                 else if (--qpriv->pending_tid_w_resp)
2161                                         rvt_mod_retry_timer(qp);
2162                                 else
2163                                         rvt_stop_rc_timers(qp);
2164                         } else {
2165                                 /*
2166                                  * We are expecting more ACKs so
2167                                  * mod the retry timer.
2168                                  */
2169                                 rvt_mod_retry_timer(qp);
2170                                 /*
2171                                  * We can stop re-sending the earlier packets
2172                                  * and continue with the next packet the
2173                                  * receiver wants.
2174                                  */
2175                                 if (cmp_psn(qp->s_psn, psn) <= 0)
2176                                         reset_psn(qp, psn + 1);
2177                         }
2178                 } else {
2179                         /* No more acks - kill all timers */
2180                         rvt_stop_rc_timers(qp);
2181                         if (cmp_psn(qp->s_psn, psn) <= 0) {
2182                                 qp->s_state = OP(SEND_LAST);
2183                                 qp->s_psn = psn + 1;
2184                         }
2185                 }
2186                 if (qp->s_flags & RVT_S_WAIT_ACK) {
2187                         qp->s_flags &= ~RVT_S_WAIT_ACK;
2188                         hfi1_schedule_send(qp);
2189                 }
2190                 rvt_get_credit(qp, aeth);
2191                 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
2192                 qp->s_retry = qp->s_retry_cnt;
2193                 /*
2194                  * If the current request is a TID RDMA WRITE request and the
2195                  * response is not a TID RDMA WRITE RESP packet, s_last_psn
2196                  * can't be advanced.
2197                  */
2198                 if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE &&
2199                     opcode != TID_OP(WRITE_RESP) &&
2200                     cmp_psn(psn, wqe->psn) >= 0)
2201                         return 1;
2202                 update_last_psn(qp, psn);
2203                 return 1;
2204
2205         case 1:         /* RNR NAK */
2206                 ibp->rvp.n_rnr_naks++;
2207                 if (qp->s_acked == qp->s_tail)
2208                         goto bail_stop;
2209                 if (qp->s_flags & RVT_S_WAIT_RNR)
2210                         goto bail_stop;
2211                 rdi = ib_to_rvt(qp->ibqp.device);
2212                 if (!(rdi->post_parms[wqe->wr.opcode].flags &
2213                        RVT_OPERATION_IGN_RNR_CNT)) {
2214                         if (qp->s_rnr_retry == 0) {
2215                                 status = IB_WC_RNR_RETRY_EXC_ERR;
2216                                 goto class_b;
2217                         }
2218                         if (qp->s_rnr_retry_cnt < 7 && qp->s_rnr_retry_cnt > 0)
2219                                 qp->s_rnr_retry--;
2220                 }
2221
2222                 /*
2223                  * The last valid PSN is the previous PSN. For TID RDMA WRITE
2224                  * request, s_last_psn should be incremented only when a TID
2225                  * RDMA WRITE RESP is received to avoid skipping lost TID RDMA
2226                  * WRITE RESP packets.
2227                  */
2228                 if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE) {
2229                         reset_psn(qp, qp->s_last_psn + 1);
2230                 } else {
2231                         update_last_psn(qp, psn - 1);
2232                         reset_psn(qp, psn);
2233                 }
2234
2235                 ibp->rvp.n_rc_resends += delta_psn(qp->s_psn, psn);
2236                 qp->s_flags &= ~(RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_ACK);
2237                 rvt_stop_rc_timers(qp);
2238                 rvt_add_rnr_timer(qp, aeth);
2239                 return 0;
2240
2241         case 3:         /* NAK */
2242                 if (qp->s_acked == qp->s_tail)
2243                         goto bail_stop;
2244                 /* The last valid PSN is the previous PSN. */
2245                 update_last_psn(qp, psn - 1);
2246                 switch ((aeth >> IB_AETH_CREDIT_SHIFT) &
2247                         IB_AETH_CREDIT_MASK) {
2248                 case 0: /* PSN sequence error */
2249                         ibp->rvp.n_seq_naks++;
2250                         /*
2251                          * Back up to the responder's expected PSN.
2252                          * Note that we might get a NAK in the middle of an
2253                          * RDMA READ response which terminates the RDMA
2254                          * READ.
2255                          */
2256                         hfi1_restart_rc(qp, psn, 0);
2257                         hfi1_schedule_send(qp);
2258                         break;
2259
2260                 case 1: /* Invalid Request */
2261                         status = IB_WC_REM_INV_REQ_ERR;
2262                         ibp->rvp.n_other_naks++;
2263                         goto class_b;
2264
2265                 case 2: /* Remote Access Error */
2266                         status = IB_WC_REM_ACCESS_ERR;
2267                         ibp->rvp.n_other_naks++;
2268                         goto class_b;
2269
2270                 case 3: /* Remote Operation Error */
2271                         status = IB_WC_REM_OP_ERR;
2272                         ibp->rvp.n_other_naks++;
2273 class_b:
2274                         if (qp->s_last == qp->s_acked) {
2275                                 if (wqe->wr.opcode == IB_WR_TID_RDMA_READ)
2276                                         hfi1_kern_read_tid_flow_free(qp);
2277
2278                                 hfi1_trdma_send_complete(qp, wqe, status);
2279                                 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
2280                         }
2281                         break;
2282
2283                 default:
2284                         /* Ignore other reserved NAK error codes */
2285                         goto reserved;
2286                 }
2287                 qp->s_retry = qp->s_retry_cnt;
2288                 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
2289                 goto bail_stop;
2290
2291         default:                /* 2: reserved */
2292 reserved:
2293                 /* Ignore reserved NAK codes. */
2294                 goto bail_stop;
2295         }
2296         /* cannot be reached  */
2297 bail_stop:
2298         rvt_stop_rc_timers(qp);
2299         return ret;
2300 }
2301
2302 /*
2303  * We have seen an out of sequence RDMA read middle or last packet.
2304  * This ACKs SENDs and RDMA writes up to the first RDMA read or atomic SWQE.
2305  */
2306 static void rdma_seq_err(struct rvt_qp *qp, struct hfi1_ibport *ibp, u32 psn,
2307                          struct hfi1_ctxtdata *rcd)
2308 {
2309         struct rvt_swqe *wqe;
2310
2311         lockdep_assert_held(&qp->s_lock);
2312         /* Remove QP from retry timer */
2313         rvt_stop_rc_timers(qp);
2314
2315         wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2316
2317         while (cmp_psn(psn, wqe->lpsn) > 0) {
2318                 if (wqe->wr.opcode == IB_WR_RDMA_READ ||
2319                     wqe->wr.opcode == IB_WR_TID_RDMA_READ ||
2320                     wqe->wr.opcode == IB_WR_TID_RDMA_WRITE ||
2321                     wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2322                     wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)
2323                         break;
2324                 wqe = do_rc_completion(qp, wqe, ibp);
2325         }
2326
2327         ibp->rvp.n_rdma_seq++;
2328         qp->r_flags |= RVT_R_RDMAR_SEQ;
2329         hfi1_restart_rc(qp, qp->s_last_psn + 1, 0);
2330         if (list_empty(&qp->rspwait)) {
2331                 qp->r_flags |= RVT_R_RSP_SEND;
2332                 rvt_get_qp(qp);
2333                 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
2334         }
2335 }
2336
2337 /**
2338  * rc_rcv_resp - process an incoming RC response packet
2339  * @packet: data packet information
2340  *
2341  * This is called from hfi1_rc_rcv() to process an incoming RC response
2342  * packet for the given QP.
2343  * Called at interrupt level.
2344  */
2345 static void rc_rcv_resp(struct hfi1_packet *packet)
2346 {
2347         struct hfi1_ctxtdata *rcd = packet->rcd;
2348         void *data = packet->payload;
2349         u32 tlen = packet->tlen;
2350         struct rvt_qp *qp = packet->qp;
2351         struct hfi1_ibport *ibp;
2352         struct ib_other_headers *ohdr = packet->ohdr;
2353         struct rvt_swqe *wqe;
2354         enum ib_wc_status status;
2355         unsigned long flags;
2356         int diff;
2357         u64 val;
2358         u32 aeth;
2359         u32 psn = ib_bth_get_psn(packet->ohdr);
2360         u32 pmtu = qp->pmtu;
2361         u16 hdrsize = packet->hlen;
2362         u8 opcode = packet->opcode;
2363         u8 pad = packet->pad;
2364         u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
2365
2366         spin_lock_irqsave(&qp->s_lock, flags);
2367         trace_hfi1_ack(qp, psn);
2368
2369         /* Ignore invalid responses. */
2370         if (cmp_psn(psn, READ_ONCE(qp->s_next_psn)) >= 0)
2371                 goto ack_done;
2372
2373         /* Ignore duplicate responses. */
2374         diff = cmp_psn(psn, qp->s_last_psn);
2375         if (unlikely(diff <= 0)) {
2376                 /* Update credits for "ghost" ACKs */
2377                 if (diff == 0 && opcode == OP(ACKNOWLEDGE)) {
2378                         aeth = be32_to_cpu(ohdr->u.aeth);
2379                         if ((aeth >> IB_AETH_NAK_SHIFT) == 0)
2380                                 rvt_get_credit(qp, aeth);
2381                 }
2382                 goto ack_done;
2383         }
2384
2385         /*
2386          * Skip everything other than the PSN we expect, if we are waiting
2387          * for a reply to a restarted RDMA read or atomic op.
2388          */
2389         if (qp->r_flags & RVT_R_RDMAR_SEQ) {
2390                 if (cmp_psn(psn, qp->s_last_psn + 1) != 0)
2391                         goto ack_done;
2392                 qp->r_flags &= ~RVT_R_RDMAR_SEQ;
2393         }
2394
2395         if (unlikely(qp->s_acked == qp->s_tail))
2396                 goto ack_done;
2397         wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2398         status = IB_WC_SUCCESS;
2399
2400         switch (opcode) {
2401         case OP(ACKNOWLEDGE):
2402         case OP(ATOMIC_ACKNOWLEDGE):
2403         case OP(RDMA_READ_RESPONSE_FIRST):
2404                 aeth = be32_to_cpu(ohdr->u.aeth);
2405                 if (opcode == OP(ATOMIC_ACKNOWLEDGE))
2406                         val = ib_u64_get(&ohdr->u.at.atomic_ack_eth);
2407                 else
2408                         val = 0;
2409                 if (!do_rc_ack(qp, aeth, psn, opcode, val, rcd) ||
2410                     opcode != OP(RDMA_READ_RESPONSE_FIRST))
2411                         goto ack_done;
2412                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2413                 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
2414                         goto ack_op_err;
2415                 /*
2416                  * If this is a response to a resent RDMA read, we
2417                  * have to be careful to copy the data to the right
2418                  * location.
2419                  */
2420                 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
2421                                                   wqe, psn, pmtu);
2422                 goto read_middle;
2423
2424         case OP(RDMA_READ_RESPONSE_MIDDLE):
2425                 /* no AETH, no ACK */
2426                 if (unlikely(cmp_psn(psn, qp->s_last_psn + 1)))
2427                         goto ack_seq_err;
2428                 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
2429                         goto ack_op_err;
2430 read_middle:
2431                 if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
2432                         goto ack_len_err;
2433                 if (unlikely(pmtu >= qp->s_rdma_read_len))
2434                         goto ack_len_err;
2435
2436                 /*
2437                  * We got a response so update the timeout.
2438                  * 4.096 usec. * (1 << qp->timeout)
2439                  */
2440                 rvt_mod_retry_timer(qp);
2441                 if (qp->s_flags & RVT_S_WAIT_ACK) {
2442                         qp->s_flags &= ~RVT_S_WAIT_ACK;
2443                         hfi1_schedule_send(qp);
2444                 }
2445
2446                 if (opcode == OP(RDMA_READ_RESPONSE_MIDDLE))
2447                         qp->s_retry = qp->s_retry_cnt;
2448
2449                 /*
2450                  * Update the RDMA receive state but do the copy w/o
2451                  * holding the locks and blocking interrupts.
2452                  */
2453                 qp->s_rdma_read_len -= pmtu;
2454                 update_last_psn(qp, psn);
2455                 spin_unlock_irqrestore(&qp->s_lock, flags);
2456                 rvt_copy_sge(qp, &qp->s_rdma_read_sge,
2457                              data, pmtu, false, false);
2458                 goto bail;
2459
2460         case OP(RDMA_READ_RESPONSE_ONLY):
2461                 aeth = be32_to_cpu(ohdr->u.aeth);
2462                 if (!do_rc_ack(qp, aeth, psn, opcode, 0, rcd))
2463                         goto ack_done;
2464                 /*
2465                  * Check that the data size is >= 0 && <= pmtu.
2466                  * Remember to account for ICRC (4).
2467                  */
2468                 if (unlikely(tlen < (hdrsize + extra_bytes)))
2469                         goto ack_len_err;
2470                 /*
2471                  * If this is a response to a resent RDMA read, we
2472                  * have to be careful to copy the data to the right
2473                  * location.
2474                  */
2475                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2476                 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
2477                                                   wqe, psn, pmtu);
2478                 goto read_last;
2479
2480         case OP(RDMA_READ_RESPONSE_LAST):
2481                 /* ACKs READ req. */
2482                 if (unlikely(cmp_psn(psn, qp->s_last_psn + 1)))
2483                         goto ack_seq_err;
2484                 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
2485                         goto ack_op_err;
2486                 /*
2487                  * Check that the data size is >= 1 && <= pmtu.
2488                  * Remember to account for ICRC (4).
2489                  */
2490                 if (unlikely(tlen <= (hdrsize + extra_bytes)))
2491                         goto ack_len_err;
2492 read_last:
2493                 tlen -= hdrsize + extra_bytes;
2494                 if (unlikely(tlen != qp->s_rdma_read_len))
2495                         goto ack_len_err;
2496                 aeth = be32_to_cpu(ohdr->u.aeth);
2497                 rvt_copy_sge(qp, &qp->s_rdma_read_sge,
2498                              data, tlen, false, false);
2499                 WARN_ON(qp->s_rdma_read_sge.num_sge);
2500                 (void)do_rc_ack(qp, aeth, psn,
2501                                  OP(RDMA_READ_RESPONSE_LAST), 0, rcd);
2502                 goto ack_done;
2503         }
2504
2505 ack_op_err:
2506         status = IB_WC_LOC_QP_OP_ERR;
2507         goto ack_err;
2508
2509 ack_seq_err:
2510         ibp = rcd_to_iport(rcd);
2511         rdma_seq_err(qp, ibp, psn, rcd);
2512         goto ack_done;
2513
2514 ack_len_err:
2515         status = IB_WC_LOC_LEN_ERR;
2516 ack_err:
2517         if (qp->s_last == qp->s_acked) {
2518                 rvt_send_complete(qp, wqe, status);
2519                 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
2520         }
2521 ack_done:
2522         spin_unlock_irqrestore(&qp->s_lock, flags);
2523 bail:
2524         return;
2525 }
2526
2527 static inline void rc_cancel_ack(struct rvt_qp *qp)
2528 {
2529         qp->r_adefered = 0;
2530         if (list_empty(&qp->rspwait))
2531                 return;
2532         list_del_init(&qp->rspwait);
2533         qp->r_flags &= ~RVT_R_RSP_NAK;
2534         rvt_put_qp(qp);
2535 }
2536
2537 /**
2538  * rc_rcv_error - process an incoming duplicate or error RC packet
2539  * @ohdr: the other headers for this packet
2540  * @data: the packet data
2541  * @qp: the QP for this packet
2542  * @opcode: the opcode for this packet
2543  * @psn: the packet sequence number for this packet
2544  * @diff: the difference between the PSN and the expected PSN
2545  *
2546  * This is called from hfi1_rc_rcv() to process an unexpected
2547  * incoming RC packet for the given QP.
2548  * Called at interrupt level.
2549  * Return 1 if no more processing is needed; otherwise return 0 to
2550  * schedule a response to be sent.
2551  */
2552 static noinline int rc_rcv_error(struct ib_other_headers *ohdr, void *data,
2553                                  struct rvt_qp *qp, u32 opcode, u32 psn,
2554                                  int diff, struct hfi1_ctxtdata *rcd)
2555 {
2556         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
2557         struct rvt_ack_entry *e;
2558         unsigned long flags;
2559         u8 prev;
2560         u8 mra; /* most recent ACK */
2561         bool old_req;
2562
2563         trace_hfi1_rcv_error(qp, psn);
2564         if (diff > 0) {
2565                 /*
2566                  * Packet sequence error.
2567                  * A NAK will ACK earlier sends and RDMA writes.
2568                  * Don't queue the NAK if we already sent one.
2569                  */
2570                 if (!qp->r_nak_state) {
2571                         ibp->rvp.n_rc_seqnak++;
2572                         qp->r_nak_state = IB_NAK_PSN_ERROR;
2573                         /* Use the expected PSN. */
2574                         qp->r_ack_psn = qp->r_psn;
2575                         /*
2576                          * Wait to send the sequence NAK until all packets
2577                          * in the receive queue have been processed.
2578                          * Otherwise, we end up propagating congestion.
2579                          */
2580                         rc_defered_ack(rcd, qp);
2581                 }
2582                 goto done;
2583         }
2584
2585         /*
2586          * Handle a duplicate request.  Don't re-execute SEND, RDMA
2587          * write or atomic op.  Don't NAK errors, just silently drop
2588          * the duplicate request.  Note that r_sge, r_len, and
2589          * r_rcv_len may be in use so don't modify them.
2590          *
2591          * We are supposed to ACK the earliest duplicate PSN but we
2592          * can coalesce an outstanding duplicate ACK.  We have to
2593          * send the earliest so that RDMA reads can be restarted at
2594          * the requester's expected PSN.
2595          *
2596          * First, find where this duplicate PSN falls within the
2597          * ACKs previously sent.
2598          * old_req is true if there is an older response that is scheduled
2599          * to be sent before sending this one.
2600          */
2601         e = NULL;
2602         old_req = 1;
2603         ibp->rvp.n_rc_dupreq++;
2604
2605         spin_lock_irqsave(&qp->s_lock, flags);
2606
2607         e = find_prev_entry(qp, psn, &prev, &mra, &old_req);
2608
2609         switch (opcode) {
2610         case OP(RDMA_READ_REQUEST): {
2611                 struct ib_reth *reth;
2612                 u32 offset;
2613                 u32 len;
2614
2615                 /*
2616                  * If we didn't find the RDMA read request in the ack queue,
2617                  * we can ignore this request.
2618                  */
2619                 if (!e || e->opcode != OP(RDMA_READ_REQUEST))
2620                         goto unlock_done;
2621                 /* RETH comes after BTH */
2622                 reth = &ohdr->u.rc.reth;
2623                 /*
2624                  * Address range must be a subset of the original
2625                  * request and start on pmtu boundaries.
2626                  * We reuse the old ack_queue slot since the requester
2627                  * should not back up and request an earlier PSN for the
2628                  * same request.
2629                  */
2630                 offset = delta_psn(psn, e->psn) * qp->pmtu;
2631                 len = be32_to_cpu(reth->length);
2632                 if (unlikely(offset + len != e->rdma_sge.sge_length))
2633                         goto unlock_done;
2634                 release_rdma_sge_mr(e);
2635                 if (len != 0) {
2636                         u32 rkey = be32_to_cpu(reth->rkey);
2637                         u64 vaddr = get_ib_reth_vaddr(reth);
2638                         int ok;
2639
2640                         ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey,
2641                                          IB_ACCESS_REMOTE_READ);
2642                         if (unlikely(!ok))
2643                                 goto unlock_done;
2644                 } else {
2645                         e->rdma_sge.vaddr = NULL;
2646                         e->rdma_sge.length = 0;
2647                         e->rdma_sge.sge_length = 0;
2648                 }
2649                 e->psn = psn;
2650                 if (old_req)
2651                         goto unlock_done;
2652                 if (qp->s_acked_ack_queue == qp->s_tail_ack_queue)
2653                         qp->s_acked_ack_queue = prev;
2654                 qp->s_tail_ack_queue = prev;
2655                 break;
2656         }
2657
2658         case OP(COMPARE_SWAP):
2659         case OP(FETCH_ADD): {
2660                 /*
2661                  * If we didn't find the atomic request in the ack queue
2662                  * or the send engine is already backed up to send an
2663                  * earlier entry, we can ignore this request.
2664                  */
2665                 if (!e || e->opcode != (u8)opcode || old_req)
2666                         goto unlock_done;
2667                 if (qp->s_tail_ack_queue == qp->s_acked_ack_queue)
2668                         qp->s_acked_ack_queue = prev;
2669                 qp->s_tail_ack_queue = prev;
2670                 break;
2671         }
2672
2673         default:
2674                 /*
2675                  * Ignore this operation if it doesn't request an ACK
2676                  * or an earlier RDMA read or atomic is going to be resent.
2677                  */
2678                 if (!(psn & IB_BTH_REQ_ACK) || old_req)
2679                         goto unlock_done;
2680                 /*
2681                  * Resend the most recent ACK if this request is
2682                  * after all the previous RDMA reads and atomics.
2683                  */
2684                 if (mra == qp->r_head_ack_queue) {
2685                         spin_unlock_irqrestore(&qp->s_lock, flags);
2686                         qp->r_nak_state = 0;
2687                         qp->r_ack_psn = qp->r_psn - 1;
2688                         goto send_ack;
2689                 }
2690
2691                 /*
2692                  * Resend the RDMA read or atomic op which
2693                  * ACKs this duplicate request.
2694                  */
2695                 if (qp->s_tail_ack_queue == qp->s_acked_ack_queue)
2696                         qp->s_acked_ack_queue = mra;
2697                 qp->s_tail_ack_queue = mra;
2698                 break;
2699         }
2700         qp->s_ack_state = OP(ACKNOWLEDGE);
2701         qp->s_flags |= RVT_S_RESP_PENDING;
2702         qp->r_nak_state = 0;
2703         hfi1_schedule_send(qp);
2704
2705 unlock_done:
2706         spin_unlock_irqrestore(&qp->s_lock, flags);
2707 done:
2708         return 1;
2709
2710 send_ack:
2711         return 0;
2712 }
2713
2714 static void log_cca_event(struct hfi1_pportdata *ppd, u8 sl, u32 rlid,
2715                           u32 lqpn, u32 rqpn, u8 svc_type)
2716 {
2717         struct opa_hfi1_cong_log_event_internal *cc_event;
2718         unsigned long flags;
2719
2720         if (sl >= OPA_MAX_SLS)
2721                 return;
2722
2723         spin_lock_irqsave(&ppd->cc_log_lock, flags);
2724
2725         ppd->threshold_cong_event_map[sl / 8] |= 1 << (sl % 8);
2726         ppd->threshold_event_counter++;
2727
2728         cc_event = &ppd->cc_events[ppd->cc_log_idx++];
2729         if (ppd->cc_log_idx == OPA_CONG_LOG_ELEMS)
2730                 ppd->cc_log_idx = 0;
2731         cc_event->lqpn = lqpn & RVT_QPN_MASK;
2732         cc_event->rqpn = rqpn & RVT_QPN_MASK;
2733         cc_event->sl = sl;
2734         cc_event->svc_type = svc_type;
2735         cc_event->rlid = rlid;
2736         /* keep timestamp in units of 1.024 usec */
2737         cc_event->timestamp = ktime_get_ns() / 1024;
2738
2739         spin_unlock_irqrestore(&ppd->cc_log_lock, flags);
2740 }
2741
2742 void process_becn(struct hfi1_pportdata *ppd, u8 sl, u32 rlid, u32 lqpn,
2743                   u32 rqpn, u8 svc_type)
2744 {
2745         struct cca_timer *cca_timer;
2746         u16 ccti, ccti_incr, ccti_timer, ccti_limit;
2747         u8 trigger_threshold;
2748         struct cc_state *cc_state;
2749         unsigned long flags;
2750
2751         if (sl >= OPA_MAX_SLS)
2752                 return;
2753
2754         cc_state = get_cc_state(ppd);
2755
2756         if (!cc_state)
2757                 return;
2758
2759         /*
2760          * 1) increase CCTI (for this SL)
2761          * 2) select IPG (i.e., call set_link_ipg())
2762          * 3) start timer
2763          */
2764         ccti_limit = cc_state->cct.ccti_limit;
2765         ccti_incr = cc_state->cong_setting.entries[sl].ccti_increase;
2766         ccti_timer = cc_state->cong_setting.entries[sl].ccti_timer;
2767         trigger_threshold =
2768                 cc_state->cong_setting.entries[sl].trigger_threshold;
2769
2770         spin_lock_irqsave(&ppd->cca_timer_lock, flags);
2771
2772         cca_timer = &ppd->cca_timer[sl];
2773         if (cca_timer->ccti < ccti_limit) {
2774                 if (cca_timer->ccti + ccti_incr <= ccti_limit)
2775                         cca_timer->ccti += ccti_incr;
2776                 else
2777                         cca_timer->ccti = ccti_limit;
2778                 set_link_ipg(ppd);
2779         }
2780
2781         ccti = cca_timer->ccti;
2782
2783         if (!hrtimer_active(&cca_timer->hrtimer)) {
2784                 /* ccti_timer is in units of 1.024 usec */
2785                 unsigned long nsec = 1024 * ccti_timer;
2786
2787                 hrtimer_start(&cca_timer->hrtimer, ns_to_ktime(nsec),
2788                               HRTIMER_MODE_REL_PINNED);
2789         }
2790
2791         spin_unlock_irqrestore(&ppd->cca_timer_lock, flags);
2792
2793         if ((trigger_threshold != 0) && (ccti >= trigger_threshold))
2794                 log_cca_event(ppd, sl, rlid, lqpn, rqpn, svc_type);
2795 }
2796
2797 /**
2798  * hfi1_rc_rcv - process an incoming RC packet
2799  * @packet: data packet information
2800  *
2801  * This is called from qp_rcv() to process an incoming RC packet
2802  * for the given QP.
2803  * May be called at interrupt level.
2804  */
2805 void hfi1_rc_rcv(struct hfi1_packet *packet)
2806 {
2807         struct hfi1_ctxtdata *rcd = packet->rcd;
2808         void *data = packet->payload;
2809         u32 tlen = packet->tlen;
2810         struct rvt_qp *qp = packet->qp;
2811         struct hfi1_qp_priv *qpriv = qp->priv;
2812         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
2813         struct ib_other_headers *ohdr = packet->ohdr;
2814         u32 opcode = packet->opcode;
2815         u32 hdrsize = packet->hlen;
2816         u32 psn = ib_bth_get_psn(packet->ohdr);
2817         u32 pad = packet->pad;
2818         struct ib_wc wc;
2819         u32 pmtu = qp->pmtu;
2820         int diff;
2821         struct ib_reth *reth;
2822         unsigned long flags;
2823         int ret;
2824         bool copy_last = false, fecn;
2825         u32 rkey;
2826         u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
2827
2828         lockdep_assert_held(&qp->r_lock);
2829
2830         if (hfi1_ruc_check_hdr(ibp, packet))
2831                 return;
2832
2833         fecn = process_ecn(qp, packet);
2834         opfn_trigger_conn_request(qp, be32_to_cpu(ohdr->bth[1]));
2835
2836         /*
2837          * Process responses (ACKs) before anything else.  Note that the
2838          * packet sequence number will be for something in the send work
2839          * queue rather than the expected receive packet sequence number.
2840          * In other words, this QP is the requester.
2841          */
2842         if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
2843             opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
2844                 rc_rcv_resp(packet);
2845                 return;
2846         }
2847
2848         /* Compute 24 bits worth of difference. */
2849         diff = delta_psn(psn, qp->r_psn);
2850         if (unlikely(diff)) {
2851                 if (rc_rcv_error(ohdr, data, qp, opcode, psn, diff, rcd))
2852                         return;
2853                 goto send_ack;
2854         }
2855
2856         /* Check for opcode sequence errors. */
2857         switch (qp->r_state) {
2858         case OP(SEND_FIRST):
2859         case OP(SEND_MIDDLE):
2860                 if (opcode == OP(SEND_MIDDLE) ||
2861                     opcode == OP(SEND_LAST) ||
2862                     opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
2863                     opcode == OP(SEND_LAST_WITH_INVALIDATE))
2864                         break;
2865                 goto nack_inv;
2866
2867         case OP(RDMA_WRITE_FIRST):
2868         case OP(RDMA_WRITE_MIDDLE):
2869                 if (opcode == OP(RDMA_WRITE_MIDDLE) ||
2870                     opcode == OP(RDMA_WRITE_LAST) ||
2871                     opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
2872                         break;
2873                 goto nack_inv;
2874
2875         default:
2876                 if (opcode == OP(SEND_MIDDLE) ||
2877                     opcode == OP(SEND_LAST) ||
2878                     opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
2879                     opcode == OP(SEND_LAST_WITH_INVALIDATE) ||
2880                     opcode == OP(RDMA_WRITE_MIDDLE) ||
2881                     opcode == OP(RDMA_WRITE_LAST) ||
2882                     opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
2883                         goto nack_inv;
2884                 /*
2885                  * Note that it is up to the requester to not send a new
2886                  * RDMA read or atomic operation before receiving an ACK
2887                  * for the previous operation.
2888                  */
2889                 break;
2890         }
2891
2892         if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST))
2893                 rvt_comm_est(qp);
2894
2895         /* OK, process the packet. */
2896         switch (opcode) {
2897         case OP(SEND_FIRST):
2898                 ret = rvt_get_rwqe(qp, false);
2899                 if (ret < 0)
2900                         goto nack_op_err;
2901                 if (!ret)
2902                         goto rnr_nak;
2903                 qp->r_rcv_len = 0;
2904                 /* FALLTHROUGH */
2905         case OP(SEND_MIDDLE):
2906         case OP(RDMA_WRITE_MIDDLE):
2907 send_middle:
2908                 /* Check for invalid length PMTU or posted rwqe len. */
2909                 /*
2910                  * There will be no padding for 9B packet but 16B packets
2911                  * will come in with some padding since we always add
2912                  * CRC and LT bytes which will need to be flit aligned
2913                  */
2914                 if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
2915                         goto nack_inv;
2916                 qp->r_rcv_len += pmtu;
2917                 if (unlikely(qp->r_rcv_len > qp->r_len))
2918                         goto nack_inv;
2919                 rvt_copy_sge(qp, &qp->r_sge, data, pmtu, true, false);
2920                 break;
2921
2922         case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
2923                 /* consume RWQE */
2924                 ret = rvt_get_rwqe(qp, true);
2925                 if (ret < 0)
2926                         goto nack_op_err;
2927                 if (!ret)
2928                         goto rnr_nak;
2929                 goto send_last_imm;
2930
2931         case OP(SEND_ONLY):
2932         case OP(SEND_ONLY_WITH_IMMEDIATE):
2933         case OP(SEND_ONLY_WITH_INVALIDATE):
2934                 ret = rvt_get_rwqe(qp, false);
2935                 if (ret < 0)
2936                         goto nack_op_err;
2937                 if (!ret)
2938                         goto rnr_nak;
2939                 qp->r_rcv_len = 0;
2940                 if (opcode == OP(SEND_ONLY))
2941                         goto no_immediate_data;
2942                 if (opcode == OP(SEND_ONLY_WITH_INVALIDATE))
2943                         goto send_last_inv;
2944                 /* FALLTHROUGH -- for SEND_ONLY_WITH_IMMEDIATE */
2945         case OP(SEND_LAST_WITH_IMMEDIATE):
2946 send_last_imm:
2947                 wc.ex.imm_data = ohdr->u.imm_data;
2948                 wc.wc_flags = IB_WC_WITH_IMM;
2949                 goto send_last;
2950         case OP(SEND_LAST_WITH_INVALIDATE):
2951 send_last_inv:
2952                 rkey = be32_to_cpu(ohdr->u.ieth);
2953                 if (rvt_invalidate_rkey(qp, rkey))
2954                         goto no_immediate_data;
2955                 wc.ex.invalidate_rkey = rkey;
2956                 wc.wc_flags = IB_WC_WITH_INVALIDATE;
2957                 goto send_last;
2958         case OP(RDMA_WRITE_LAST):
2959                 copy_last = rvt_is_user_qp(qp);
2960                 /* fall through */
2961         case OP(SEND_LAST):
2962 no_immediate_data:
2963                 wc.wc_flags = 0;
2964                 wc.ex.imm_data = 0;
2965 send_last:
2966                 /* Check for invalid length. */
2967                 /* LAST len should be >= 1 */
2968                 if (unlikely(tlen < (hdrsize + extra_bytes)))
2969                         goto nack_inv;
2970                 /* Don't count the CRC(and padding and LT byte for 16B). */
2971                 tlen -= (hdrsize + extra_bytes);
2972                 wc.byte_len = tlen + qp->r_rcv_len;
2973                 if (unlikely(wc.byte_len > qp->r_len))
2974                         goto nack_inv;
2975                 rvt_copy_sge(qp, &qp->r_sge, data, tlen, true, copy_last);
2976                 rvt_put_ss(&qp->r_sge);
2977                 qp->r_msn++;
2978                 if (!__test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
2979                         break;
2980                 wc.wr_id = qp->r_wr_id;
2981                 wc.status = IB_WC_SUCCESS;
2982                 if (opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE) ||
2983                     opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
2984                         wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
2985                 else
2986                         wc.opcode = IB_WC_RECV;
2987                 wc.qp = &qp->ibqp;
2988                 wc.src_qp = qp->remote_qpn;
2989                 wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
2990                 /*
2991                  * It seems that IB mandates the presence of an SL in a
2992                  * work completion only for the UD transport (see section
2993                  * 11.4.2 of IBTA Vol. 1).
2994                  *
2995                  * However, the way the SL is chosen below is consistent
2996                  * with the way that IB/qib works and is trying avoid
2997                  * introducing incompatibilities.
2998                  *
2999                  * See also OPA Vol. 1, section 9.7.6, and table 9-17.
3000                  */
3001                 wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
3002                 /* zero fields that are N/A */
3003                 wc.vendor_err = 0;
3004                 wc.pkey_index = 0;
3005                 wc.dlid_path_bits = 0;
3006                 wc.port_num = 0;
3007                 /* Signal completion event if the solicited bit is set. */
3008                 rvt_recv_cq(qp, &wc, ib_bth_is_solicited(ohdr));
3009                 break;
3010
3011         case OP(RDMA_WRITE_ONLY):
3012                 copy_last = rvt_is_user_qp(qp);
3013                 /* fall through */
3014         case OP(RDMA_WRITE_FIRST):
3015         case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
3016                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
3017                         goto nack_inv;
3018                 /* consume RWQE */
3019                 reth = &ohdr->u.rc.reth;
3020                 qp->r_len = be32_to_cpu(reth->length);
3021                 qp->r_rcv_len = 0;
3022                 qp->r_sge.sg_list = NULL;
3023                 if (qp->r_len != 0) {
3024                         u32 rkey = be32_to_cpu(reth->rkey);
3025                         u64 vaddr = get_ib_reth_vaddr(reth);
3026                         int ok;
3027
3028                         /* Check rkey & NAK */
3029                         ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len, vaddr,
3030                                          rkey, IB_ACCESS_REMOTE_WRITE);
3031                         if (unlikely(!ok))
3032                                 goto nack_acc;
3033                         qp->r_sge.num_sge = 1;
3034                 } else {
3035                         qp->r_sge.num_sge = 0;
3036                         qp->r_sge.sge.mr = NULL;
3037                         qp->r_sge.sge.vaddr = NULL;
3038                         qp->r_sge.sge.length = 0;
3039                         qp->r_sge.sge.sge_length = 0;
3040                 }
3041                 if (opcode == OP(RDMA_WRITE_FIRST))
3042                         goto send_middle;
3043                 else if (opcode == OP(RDMA_WRITE_ONLY))
3044                         goto no_immediate_data;
3045                 ret = rvt_get_rwqe(qp, true);
3046                 if (ret < 0)
3047                         goto nack_op_err;
3048                 if (!ret) {
3049                         /* peer will send again */
3050                         rvt_put_ss(&qp->r_sge);
3051                         goto rnr_nak;
3052                 }
3053                 wc.ex.imm_data = ohdr->u.rc.imm_data;
3054                 wc.wc_flags = IB_WC_WITH_IMM;
3055                 goto send_last;
3056
3057         case OP(RDMA_READ_REQUEST): {
3058                 struct rvt_ack_entry *e;
3059                 u32 len;
3060                 u8 next;
3061
3062                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
3063                         goto nack_inv;
3064                 next = qp->r_head_ack_queue + 1;
3065                 /* s_ack_queue is size rvt_size_atomic()+1 so use > not >= */
3066                 if (next > rvt_size_atomic(ib_to_rvt(qp->ibqp.device)))
3067                         next = 0;
3068                 spin_lock_irqsave(&qp->s_lock, flags);
3069                 if (unlikely(next == qp->s_acked_ack_queue)) {
3070                         if (!qp->s_ack_queue[next].sent)
3071                                 goto nack_inv_unlck;
3072                         update_ack_queue(qp, next);
3073                 }
3074                 e = &qp->s_ack_queue[qp->r_head_ack_queue];
3075                 release_rdma_sge_mr(e);
3076                 reth = &ohdr->u.rc.reth;
3077                 len = be32_to_cpu(reth->length);
3078                 if (len) {
3079                         u32 rkey = be32_to_cpu(reth->rkey);
3080                         u64 vaddr = get_ib_reth_vaddr(reth);
3081                         int ok;
3082
3083                         /* Check rkey & NAK */
3084                         ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr,
3085                                          rkey, IB_ACCESS_REMOTE_READ);
3086                         if (unlikely(!ok))
3087                                 goto nack_acc_unlck;
3088                         /*
3089                          * Update the next expected PSN.  We add 1 later
3090                          * below, so only add the remainder here.
3091                          */
3092                         qp->r_psn += rvt_div_mtu(qp, len - 1);
3093                 } else {
3094                         e->rdma_sge.mr = NULL;
3095                         e->rdma_sge.vaddr = NULL;
3096                         e->rdma_sge.length = 0;
3097                         e->rdma_sge.sge_length = 0;
3098                 }
3099                 e->opcode = opcode;
3100                 e->sent = 0;
3101                 e->psn = psn;
3102                 e->lpsn = qp->r_psn;
3103                 /*
3104                  * We need to increment the MSN here instead of when we
3105                  * finish sending the result since a duplicate request would
3106                  * increment it more than once.
3107                  */
3108                 qp->r_msn++;
3109                 qp->r_psn++;
3110                 qp->r_state = opcode;
3111                 qp->r_nak_state = 0;
3112                 qp->r_head_ack_queue = next;
3113                 qpriv->r_tid_alloc = qp->r_head_ack_queue;
3114
3115                 /* Schedule the send engine. */
3116                 qp->s_flags |= RVT_S_RESP_PENDING;
3117                 if (fecn)
3118                         qp->s_flags |= RVT_S_ECN;
3119                 hfi1_schedule_send(qp);
3120
3121                 spin_unlock_irqrestore(&qp->s_lock, flags);
3122                 return;
3123         }
3124
3125         case OP(COMPARE_SWAP):
3126         case OP(FETCH_ADD): {
3127                 struct ib_atomic_eth *ateth = &ohdr->u.atomic_eth;
3128                 u64 vaddr = get_ib_ateth_vaddr(ateth);
3129                 bool opfn = opcode == OP(COMPARE_SWAP) &&
3130                         vaddr == HFI1_VERBS_E_ATOMIC_VADDR;
3131                 struct rvt_ack_entry *e;
3132                 atomic64_t *maddr;
3133                 u64 sdata;
3134                 u32 rkey;
3135                 u8 next;
3136
3137                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC) &&
3138                              !opfn))
3139                         goto nack_inv;
3140                 next = qp->r_head_ack_queue + 1;
3141                 if (next > rvt_size_atomic(ib_to_rvt(qp->ibqp.device)))
3142                         next = 0;
3143                 spin_lock_irqsave(&qp->s_lock, flags);
3144                 if (unlikely(next == qp->s_acked_ack_queue)) {
3145                         if (!qp->s_ack_queue[next].sent)
3146                                 goto nack_inv_unlck;
3147                         update_ack_queue(qp, next);
3148                 }
3149                 e = &qp->s_ack_queue[qp->r_head_ack_queue];
3150                 release_rdma_sge_mr(e);
3151                 /* Process OPFN special virtual address */
3152                 if (opfn) {
3153                         opfn_conn_response(qp, e, ateth);
3154                         goto ack;
3155                 }
3156                 if (unlikely(vaddr & (sizeof(u64) - 1)))
3157                         goto nack_inv_unlck;
3158                 rkey = be32_to_cpu(ateth->rkey);
3159                 /* Check rkey & NAK */
3160                 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
3161                                           vaddr, rkey,
3162                                           IB_ACCESS_REMOTE_ATOMIC)))
3163                         goto nack_acc_unlck;
3164                 /* Perform atomic OP and save result. */
3165                 maddr = (atomic64_t *)qp->r_sge.sge.vaddr;
3166                 sdata = get_ib_ateth_swap(ateth);
3167                 e->atomic_data = (opcode == OP(FETCH_ADD)) ?
3168                         (u64)atomic64_add_return(sdata, maddr) - sdata :
3169                         (u64)cmpxchg((u64 *)qp->r_sge.sge.vaddr,
3170                                       get_ib_ateth_compare(ateth),
3171                                       sdata);
3172                 rvt_put_mr(qp->r_sge.sge.mr);
3173                 qp->r_sge.num_sge = 0;
3174 ack:
3175                 e->opcode = opcode;
3176                 e->sent = 0;
3177                 e->psn = psn;
3178                 e->lpsn = psn;
3179                 qp->r_msn++;
3180                 qp->r_psn++;
3181                 qp->r_state = opcode;
3182                 qp->r_nak_state = 0;
3183                 qp->r_head_ack_queue = next;
3184                 qpriv->r_tid_alloc = qp->r_head_ack_queue;
3185
3186                 /* Schedule the send engine. */
3187                 qp->s_flags |= RVT_S_RESP_PENDING;
3188                 if (fecn)
3189                         qp->s_flags |= RVT_S_ECN;
3190                 hfi1_schedule_send(qp);
3191
3192                 spin_unlock_irqrestore(&qp->s_lock, flags);
3193                 return;
3194         }
3195
3196         default:
3197                 /* NAK unknown opcodes. */
3198                 goto nack_inv;
3199         }
3200         qp->r_psn++;
3201         qp->r_state = opcode;
3202         qp->r_ack_psn = psn;
3203         qp->r_nak_state = 0;
3204         /* Send an ACK if requested or required. */
3205         if (psn & IB_BTH_REQ_ACK || fecn) {
3206                 if (packet->numpkt == 0 || fecn ||
3207                     qp->r_adefered >= HFI1_PSN_CREDIT) {
3208                         rc_cancel_ack(qp);
3209                         goto send_ack;
3210                 }
3211                 qp->r_adefered++;
3212                 rc_defered_ack(rcd, qp);
3213         }
3214         return;
3215
3216 rnr_nak:
3217         qp->r_nak_state = qp->r_min_rnr_timer | IB_RNR_NAK;
3218         qp->r_ack_psn = qp->r_psn;
3219         /* Queue RNR NAK for later */
3220         rc_defered_ack(rcd, qp);
3221         return;
3222
3223 nack_op_err:
3224         rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
3225         qp->r_nak_state = IB_NAK_REMOTE_OPERATIONAL_ERROR;
3226         qp->r_ack_psn = qp->r_psn;
3227         /* Queue NAK for later */
3228         rc_defered_ack(rcd, qp);
3229         return;
3230
3231 nack_inv_unlck:
3232         spin_unlock_irqrestore(&qp->s_lock, flags);
3233 nack_inv:
3234         rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
3235         qp->r_nak_state = IB_NAK_INVALID_REQUEST;
3236         qp->r_ack_psn = qp->r_psn;
3237         /* Queue NAK for later */
3238         rc_defered_ack(rcd, qp);
3239         return;
3240
3241 nack_acc_unlck:
3242         spin_unlock_irqrestore(&qp->s_lock, flags);
3243 nack_acc:
3244         rvt_rc_error(qp, IB_WC_LOC_PROT_ERR);
3245         qp->r_nak_state = IB_NAK_REMOTE_ACCESS_ERROR;
3246         qp->r_ack_psn = qp->r_psn;
3247 send_ack:
3248         hfi1_send_rc_ack(packet, fecn);
3249 }
3250
3251 void hfi1_rc_hdrerr(
3252         struct hfi1_ctxtdata *rcd,
3253         struct hfi1_packet *packet,
3254         struct rvt_qp *qp)
3255 {
3256         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
3257         int diff;
3258         u32 opcode;
3259         u32 psn;
3260
3261         if (hfi1_ruc_check_hdr(ibp, packet))
3262                 return;
3263
3264         psn = ib_bth_get_psn(packet->ohdr);
3265         opcode = ib_bth_get_opcode(packet->ohdr);
3266
3267         /* Only deal with RDMA Writes for now */
3268         if (opcode < IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) {
3269                 diff = delta_psn(psn, qp->r_psn);
3270                 if (!qp->r_nak_state && diff >= 0) {
3271                         ibp->rvp.n_rc_seqnak++;
3272                         qp->r_nak_state = IB_NAK_PSN_ERROR;
3273                         /* Use the expected PSN. */
3274                         qp->r_ack_psn = qp->r_psn;
3275                         /*
3276                          * Wait to send the sequence
3277                          * NAK until all packets
3278                          * in the receive queue have
3279                          * been processed.
3280                          * Otherwise, we end up
3281                          * propagating congestion.
3282                          */
3283                         rc_defered_ack(rcd, qp);
3284                 } /* Out of sequence NAK */
3285         } /* QP Request NAKs */
3286 }