Merge tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdim...
[sfrench/cifs-2.6.git] / drivers / infiniband / hw / hfi1 / rc.c
1 /*
2  * Copyright(c) 2015, 2016 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 "verbs_txreq.h"
55 #include "trace.h"
56
57 /* cut down ridiculously long IB macro names */
58 #define OP(x) RC_OP(x)
59
60 static u32 restart_sge(struct rvt_sge_state *ss, struct rvt_swqe *wqe,
61                        u32 psn, u32 pmtu)
62 {
63         u32 len;
64
65         len = delta_psn(psn, wqe->psn) * pmtu;
66         ss->sge = wqe->sg_list[0];
67         ss->sg_list = wqe->sg_list + 1;
68         ss->num_sge = wqe->wr.num_sge;
69         ss->total_len = wqe->length;
70         rvt_skip_sge(ss, len, false);
71         return wqe->length - len;
72 }
73
74 /**
75  * make_rc_ack - construct a response packet (ACK, NAK, or RDMA read)
76  * @dev: the device for this QP
77  * @qp: a pointer to the QP
78  * @ohdr: a pointer to the IB header being constructed
79  * @ps: the xmit packet state
80  *
81  * Return 1 if constructed; otherwise, return 0.
82  * Note that we are in the responder's side of the QP context.
83  * Note the QP s_lock must be held.
84  */
85 static int make_rc_ack(struct hfi1_ibdev *dev, struct rvt_qp *qp,
86                        struct ib_other_headers *ohdr,
87                        struct hfi1_pkt_state *ps)
88 {
89         struct rvt_ack_entry *e;
90         u32 hwords;
91         u32 len;
92         u32 bth0;
93         u32 bth2;
94         int middle = 0;
95         u32 pmtu = qp->pmtu;
96         struct hfi1_qp_priv *priv = qp->priv;
97
98         lockdep_assert_held(&qp->s_lock);
99         /* Don't send an ACK if we aren't supposed to. */
100         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
101                 goto bail;
102
103         if (priv->hdr_type == HFI1_PKT_TYPE_9B)
104                 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
105                 hwords = 5;
106         else
107                 /* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
108                 hwords = 7;
109
110         switch (qp->s_ack_state) {
111         case OP(RDMA_READ_RESPONSE_LAST):
112         case OP(RDMA_READ_RESPONSE_ONLY):
113                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
114                 if (e->rdma_sge.mr) {
115                         rvt_put_mr(e->rdma_sge.mr);
116                         e->rdma_sge.mr = NULL;
117                 }
118                 /* FALLTHROUGH */
119         case OP(ATOMIC_ACKNOWLEDGE):
120                 /*
121                  * We can increment the tail pointer now that the last
122                  * response has been sent instead of only being
123                  * constructed.
124                  */
125                 if (++qp->s_tail_ack_queue > HFI1_MAX_RDMA_ATOMIC)
126                         qp->s_tail_ack_queue = 0;
127                 /* FALLTHROUGH */
128         case OP(SEND_ONLY):
129         case OP(ACKNOWLEDGE):
130                 /* Check for no next entry in the queue. */
131                 if (qp->r_head_ack_queue == qp->s_tail_ack_queue) {
132                         if (qp->s_flags & RVT_S_ACK_PENDING)
133                                 goto normal;
134                         goto bail;
135                 }
136
137                 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
138                 if (e->opcode == OP(RDMA_READ_REQUEST)) {
139                         /*
140                          * If a RDMA read response is being resent and
141                          * we haven't seen the duplicate request yet,
142                          * then stop sending the remaining responses the
143                          * responder has seen until the requester re-sends it.
144                          */
145                         len = e->rdma_sge.sge_length;
146                         if (len && !e->rdma_sge.mr) {
147                                 qp->s_tail_ack_queue = qp->r_head_ack_queue;
148                                 goto bail;
149                         }
150                         /* Copy SGE state in case we need to resend */
151                         ps->s_txreq->mr = e->rdma_sge.mr;
152                         if (ps->s_txreq->mr)
153                                 rvt_get_mr(ps->s_txreq->mr);
154                         qp->s_ack_rdma_sge.sge = e->rdma_sge;
155                         qp->s_ack_rdma_sge.num_sge = 1;
156                         ps->s_txreq->ss = &qp->s_ack_rdma_sge;
157                         if (len > pmtu) {
158                                 len = pmtu;
159                                 qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST);
160                         } else {
161                                 qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY);
162                                 e->sent = 1;
163                         }
164                         ohdr->u.aeth = rvt_compute_aeth(qp);
165                         hwords++;
166                         qp->s_ack_rdma_psn = e->psn;
167                         bth2 = mask_psn(qp->s_ack_rdma_psn++);
168                 } else {
169                         /* COMPARE_SWAP or FETCH_ADD */
170                         ps->s_txreq->ss = NULL;
171                         len = 0;
172                         qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
173                         ohdr->u.at.aeth = rvt_compute_aeth(qp);
174                         ib_u64_put(e->atomic_data, &ohdr->u.at.atomic_ack_eth);
175                         hwords += sizeof(ohdr->u.at) / sizeof(u32);
176                         bth2 = mask_psn(e->psn);
177                         e->sent = 1;
178                 }
179                 bth0 = qp->s_ack_state << 24;
180                 break;
181
182         case OP(RDMA_READ_RESPONSE_FIRST):
183                 qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE);
184                 /* FALLTHROUGH */
185         case OP(RDMA_READ_RESPONSE_MIDDLE):
186                 ps->s_txreq->ss = &qp->s_ack_rdma_sge;
187                 ps->s_txreq->mr = qp->s_ack_rdma_sge.sge.mr;
188                 if (ps->s_txreq->mr)
189                         rvt_get_mr(ps->s_txreq->mr);
190                 len = qp->s_ack_rdma_sge.sge.sge_length;
191                 if (len > pmtu) {
192                         len = pmtu;
193                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
194                 } else {
195                         ohdr->u.aeth = rvt_compute_aeth(qp);
196                         hwords++;
197                         qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
198                         e = &qp->s_ack_queue[qp->s_tail_ack_queue];
199                         e->sent = 1;
200                 }
201                 bth0 = qp->s_ack_state << 24;
202                 bth2 = mask_psn(qp->s_ack_rdma_psn++);
203                 break;
204
205         default:
206 normal:
207                 /*
208                  * Send a regular ACK.
209                  * Set the s_ack_state so we wait until after sending
210                  * the ACK before setting s_ack_state to ACKNOWLEDGE
211                  * (see above).
212                  */
213                 qp->s_ack_state = OP(SEND_ONLY);
214                 qp->s_flags &= ~RVT_S_ACK_PENDING;
215                 ps->s_txreq->ss = NULL;
216                 if (qp->s_nak_state)
217                         ohdr->u.aeth =
218                                 cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
219                                             (qp->s_nak_state <<
220                                              IB_AETH_CREDIT_SHIFT));
221                 else
222                         ohdr->u.aeth = rvt_compute_aeth(qp);
223                 hwords++;
224                 len = 0;
225                 bth0 = OP(ACKNOWLEDGE) << 24;
226                 bth2 = mask_psn(qp->s_ack_psn);
227         }
228         qp->s_rdma_ack_cnt++;
229         qp->s_hdrwords = hwords;
230         ps->s_txreq->sde = priv->s_sde;
231         ps->s_txreq->s_cur_size = len;
232         hfi1_make_ruc_header(qp, ohdr, bth0, bth2, middle, ps);
233         /* pbc */
234         ps->s_txreq->hdr_dwords = qp->s_hdrwords + 2;
235         return 1;
236
237 bail:
238         qp->s_ack_state = OP(ACKNOWLEDGE);
239         /*
240          * Ensure s_rdma_ack_cnt changes are committed prior to resetting
241          * RVT_S_RESP_PENDING
242          */
243         smp_wmb();
244         qp->s_flags &= ~(RVT_S_RESP_PENDING
245                                 | RVT_S_ACK_PENDING
246                                 | RVT_S_AHG_VALID);
247         return 0;
248 }
249
250 /**
251  * hfi1_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC)
252  * @qp: a pointer to the QP
253  *
254  * Assumes s_lock is held.
255  *
256  * Return 1 if constructed; otherwise, return 0.
257  */
258 int hfi1_make_rc_req(struct rvt_qp *qp, struct hfi1_pkt_state *ps)
259 {
260         struct hfi1_qp_priv *priv = qp->priv;
261         struct hfi1_ibdev *dev = to_idev(qp->ibqp.device);
262         struct ib_other_headers *ohdr;
263         struct rvt_sge_state *ss;
264         struct rvt_swqe *wqe;
265         u32 hwords;
266         u32 len;
267         u32 bth0 = 0;
268         u32 bth2;
269         u32 pmtu = qp->pmtu;
270         char newreq;
271         int middle = 0;
272         int delta;
273
274         lockdep_assert_held(&qp->s_lock);
275         ps->s_txreq = get_txreq(ps->dev, qp);
276         if (IS_ERR(ps->s_txreq))
277                 goto bail_no_tx;
278
279         if (priv->hdr_type == HFI1_PKT_TYPE_9B) {
280                 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
281                 hwords = 5;
282                 if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)
283                         ohdr = &ps->s_txreq->phdr.hdr.ibh.u.l.oth;
284                 else
285                         ohdr = &ps->s_txreq->phdr.hdr.ibh.u.oth;
286         } else {
287                 /* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
288                 hwords = 7;
289                 if ((rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
290                     (hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))))
291                         ohdr = &ps->s_txreq->phdr.hdr.opah.u.l.oth;
292                 else
293                         ohdr = &ps->s_txreq->phdr.hdr.opah.u.oth;
294         }
295
296         /* Sending responses has higher priority over sending requests. */
297         if ((qp->s_flags & RVT_S_RESP_PENDING) &&
298             make_rc_ack(dev, qp, ohdr, ps))
299                 return 1;
300
301         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
302                 if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND))
303                         goto bail;
304                 /* We are in the error state, flush the work request. */
305                 if (qp->s_last == READ_ONCE(qp->s_head))
306                         goto bail;
307                 /* If DMAs are in progress, we can't flush immediately. */
308                 if (iowait_sdma_pending(&priv->s_iowait)) {
309                         qp->s_flags |= RVT_S_WAIT_DMA;
310                         goto bail;
311                 }
312                 clear_ahg(qp);
313                 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
314                 hfi1_send_complete(qp, wqe, qp->s_last != qp->s_acked ?
315                         IB_WC_SUCCESS : IB_WC_WR_FLUSH_ERR);
316                 /* will get called again */
317                 goto done_free_tx;
318         }
319
320         if (qp->s_flags & (RVT_S_WAIT_RNR | RVT_S_WAIT_ACK))
321                 goto bail;
322
323         if (cmp_psn(qp->s_psn, qp->s_sending_hpsn) <= 0) {
324                 if (cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0) {
325                         qp->s_flags |= RVT_S_WAIT_PSN;
326                         goto bail;
327                 }
328                 qp->s_sending_psn = qp->s_psn;
329                 qp->s_sending_hpsn = qp->s_psn - 1;
330         }
331
332         /* Send a request. */
333         wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
334         switch (qp->s_state) {
335         default:
336                 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_NEXT_SEND_OK))
337                         goto bail;
338                 /*
339                  * Resend an old request or start a new one.
340                  *
341                  * We keep track of the current SWQE so that
342                  * we don't reset the "furthest progress" state
343                  * if we need to back up.
344                  */
345                 newreq = 0;
346                 if (qp->s_cur == qp->s_tail) {
347                         /* Check if send work queue is empty. */
348                         if (qp->s_tail == READ_ONCE(qp->s_head)) {
349                                 clear_ahg(qp);
350                                 goto bail;
351                         }
352                         /*
353                          * If a fence is requested, wait for previous
354                          * RDMA read and atomic operations to finish.
355                          */
356                         if ((wqe->wr.send_flags & IB_SEND_FENCE) &&
357                             qp->s_num_rd_atomic) {
358                                 qp->s_flags |= RVT_S_WAIT_FENCE;
359                                 goto bail;
360                         }
361                         /*
362                          * Local operations are processed immediately
363                          * after all prior requests have completed
364                          */
365                         if (wqe->wr.opcode == IB_WR_REG_MR ||
366                             wqe->wr.opcode == IB_WR_LOCAL_INV) {
367                                 int local_ops = 0;
368                                 int err = 0;
369
370                                 if (qp->s_last != qp->s_cur)
371                                         goto bail;
372                                 if (++qp->s_cur == qp->s_size)
373                                         qp->s_cur = 0;
374                                 if (++qp->s_tail == qp->s_size)
375                                         qp->s_tail = 0;
376                                 if (!(wqe->wr.send_flags &
377                                       RVT_SEND_COMPLETION_ONLY)) {
378                                         err = rvt_invalidate_rkey(
379                                                 qp,
380                                                 wqe->wr.ex.invalidate_rkey);
381                                         local_ops = 1;
382                                 }
383                                 hfi1_send_complete(qp, wqe,
384                                                    err ? IB_WC_LOC_PROT_ERR
385                                                        : IB_WC_SUCCESS);
386                                 if (local_ops)
387                                         atomic_dec(&qp->local_ops_pending);
388                                 qp->s_hdrwords = 0;
389                                 goto done_free_tx;
390                         }
391
392                         newreq = 1;
393                         qp->s_psn = wqe->psn;
394                 }
395                 /*
396                  * Note that we have to be careful not to modify the
397                  * original work request since we may need to resend
398                  * it.
399                  */
400                 len = wqe->length;
401                 ss = &qp->s_sge;
402                 bth2 = mask_psn(qp->s_psn);
403                 switch (wqe->wr.opcode) {
404                 case IB_WR_SEND:
405                 case IB_WR_SEND_WITH_IMM:
406                 case IB_WR_SEND_WITH_INV:
407                         /* If no credit, return. */
408                         if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
409                             rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
410                                 qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
411                                 goto bail;
412                         }
413                         if (len > pmtu) {
414                                 qp->s_state = OP(SEND_FIRST);
415                                 len = pmtu;
416                                 break;
417                         }
418                         if (wqe->wr.opcode == IB_WR_SEND) {
419                                 qp->s_state = OP(SEND_ONLY);
420                         } else if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
421                                 qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE);
422                                 /* Immediate data comes after the BTH */
423                                 ohdr->u.imm_data = wqe->wr.ex.imm_data;
424                                 hwords += 1;
425                         } else {
426                                 qp->s_state = OP(SEND_ONLY_WITH_INVALIDATE);
427                                 /* Invalidate rkey comes after the BTH */
428                                 ohdr->u.ieth = cpu_to_be32(
429                                                 wqe->wr.ex.invalidate_rkey);
430                                 hwords += 1;
431                         }
432                         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
433                                 bth0 |= IB_BTH_SOLICITED;
434                         bth2 |= IB_BTH_REQ_ACK;
435                         if (++qp->s_cur == qp->s_size)
436                                 qp->s_cur = 0;
437                         break;
438
439                 case IB_WR_RDMA_WRITE:
440                         if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
441                                 qp->s_lsn++;
442                         goto no_flow_control;
443                 case IB_WR_RDMA_WRITE_WITH_IMM:
444                         /* If no credit, return. */
445                         if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
446                             rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
447                                 qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
448                                 goto bail;
449                         }
450 no_flow_control:
451                         put_ib_reth_vaddr(
452                                 wqe->rdma_wr.remote_addr,
453                                 &ohdr->u.rc.reth);
454                         ohdr->u.rc.reth.rkey =
455                                 cpu_to_be32(wqe->rdma_wr.rkey);
456                         ohdr->u.rc.reth.length = cpu_to_be32(len);
457                         hwords += sizeof(struct ib_reth) / sizeof(u32);
458                         if (len > pmtu) {
459                                 qp->s_state = OP(RDMA_WRITE_FIRST);
460                                 len = pmtu;
461                                 break;
462                         }
463                         if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
464                                 qp->s_state = OP(RDMA_WRITE_ONLY);
465                         } else {
466                                 qp->s_state =
467                                         OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE);
468                                 /* Immediate data comes after RETH */
469                                 ohdr->u.rc.imm_data = wqe->wr.ex.imm_data;
470                                 hwords += 1;
471                                 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
472                                         bth0 |= IB_BTH_SOLICITED;
473                         }
474                         bth2 |= IB_BTH_REQ_ACK;
475                         if (++qp->s_cur == qp->s_size)
476                                 qp->s_cur = 0;
477                         break;
478
479                 case IB_WR_RDMA_READ:
480                         /*
481                          * Don't allow more operations to be started
482                          * than the QP limits allow.
483                          */
484                         if (newreq) {
485                                 if (qp->s_num_rd_atomic >=
486                                     qp->s_max_rd_atomic) {
487                                         qp->s_flags |= RVT_S_WAIT_RDMAR;
488                                         goto bail;
489                                 }
490                                 qp->s_num_rd_atomic++;
491                                 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
492                                         qp->s_lsn++;
493                         }
494                         put_ib_reth_vaddr(
495                                 wqe->rdma_wr.remote_addr,
496                                 &ohdr->u.rc.reth);
497                         ohdr->u.rc.reth.rkey =
498                                 cpu_to_be32(wqe->rdma_wr.rkey);
499                         ohdr->u.rc.reth.length = cpu_to_be32(len);
500                         qp->s_state = OP(RDMA_READ_REQUEST);
501                         hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
502                         ss = NULL;
503                         len = 0;
504                         bth2 |= IB_BTH_REQ_ACK;
505                         if (++qp->s_cur == qp->s_size)
506                                 qp->s_cur = 0;
507                         break;
508
509                 case IB_WR_ATOMIC_CMP_AND_SWP:
510                 case IB_WR_ATOMIC_FETCH_AND_ADD:
511                         /*
512                          * Don't allow more operations to be started
513                          * than the QP limits allow.
514                          */
515                         if (newreq) {
516                                 if (qp->s_num_rd_atomic >=
517                                     qp->s_max_rd_atomic) {
518                                         qp->s_flags |= RVT_S_WAIT_RDMAR;
519                                         goto bail;
520                                 }
521                                 qp->s_num_rd_atomic++;
522                                 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
523                                         qp->s_lsn++;
524                         }
525                         if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP) {
526                                 qp->s_state = OP(COMPARE_SWAP);
527                                 put_ib_ateth_swap(wqe->atomic_wr.swap,
528                                                   &ohdr->u.atomic_eth);
529                                 put_ib_ateth_compare(wqe->atomic_wr.compare_add,
530                                                      &ohdr->u.atomic_eth);
531                         } else {
532                                 qp->s_state = OP(FETCH_ADD);
533                                 put_ib_ateth_swap(wqe->atomic_wr.compare_add,
534                                                   &ohdr->u.atomic_eth);
535                                 put_ib_ateth_compare(0, &ohdr->u.atomic_eth);
536                         }
537                         put_ib_ateth_vaddr(wqe->atomic_wr.remote_addr,
538                                            &ohdr->u.atomic_eth);
539                         ohdr->u.atomic_eth.rkey = cpu_to_be32(
540                                 wqe->atomic_wr.rkey);
541                         hwords += sizeof(struct ib_atomic_eth) / sizeof(u32);
542                         ss = NULL;
543                         len = 0;
544                         bth2 |= IB_BTH_REQ_ACK;
545                         if (++qp->s_cur == qp->s_size)
546                                 qp->s_cur = 0;
547                         break;
548
549                 default:
550                         goto bail;
551                 }
552                 qp->s_sge.sge = wqe->sg_list[0];
553                 qp->s_sge.sg_list = wqe->sg_list + 1;
554                 qp->s_sge.num_sge = wqe->wr.num_sge;
555                 qp->s_sge.total_len = wqe->length;
556                 qp->s_len = wqe->length;
557                 if (newreq) {
558                         qp->s_tail++;
559                         if (qp->s_tail >= qp->s_size)
560                                 qp->s_tail = 0;
561                 }
562                 if (wqe->wr.opcode == IB_WR_RDMA_READ)
563                         qp->s_psn = wqe->lpsn + 1;
564                 else
565                         qp->s_psn++;
566                 break;
567
568         case OP(RDMA_READ_RESPONSE_FIRST):
569                 /*
570                  * qp->s_state is normally set to the opcode of the
571                  * last packet constructed for new requests and therefore
572                  * is never set to RDMA read response.
573                  * RDMA_READ_RESPONSE_FIRST is used by the ACK processing
574                  * thread to indicate a SEND needs to be restarted from an
575                  * earlier PSN without interfering with the sending thread.
576                  * See restart_rc().
577                  */
578                 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
579                 /* FALLTHROUGH */
580         case OP(SEND_FIRST):
581                 qp->s_state = OP(SEND_MIDDLE);
582                 /* FALLTHROUGH */
583         case OP(SEND_MIDDLE):
584                 bth2 = mask_psn(qp->s_psn++);
585                 ss = &qp->s_sge;
586                 len = qp->s_len;
587                 if (len > pmtu) {
588                         len = pmtu;
589                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
590                         break;
591                 }
592                 if (wqe->wr.opcode == IB_WR_SEND) {
593                         qp->s_state = OP(SEND_LAST);
594                 } else if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
595                         qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE);
596                         /* Immediate data comes after the BTH */
597                         ohdr->u.imm_data = wqe->wr.ex.imm_data;
598                         hwords += 1;
599                 } else {
600                         qp->s_state = OP(SEND_LAST_WITH_INVALIDATE);
601                         /* invalidate data comes after the BTH */
602                         ohdr->u.ieth = cpu_to_be32(wqe->wr.ex.invalidate_rkey);
603                         hwords += 1;
604                 }
605                 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
606                         bth0 |= IB_BTH_SOLICITED;
607                 bth2 |= IB_BTH_REQ_ACK;
608                 qp->s_cur++;
609                 if (qp->s_cur >= qp->s_size)
610                         qp->s_cur = 0;
611                 break;
612
613         case OP(RDMA_READ_RESPONSE_LAST):
614                 /*
615                  * qp->s_state is normally set to the opcode of the
616                  * last packet constructed for new requests and therefore
617                  * is never set to RDMA read response.
618                  * RDMA_READ_RESPONSE_LAST is used by the ACK processing
619                  * thread to indicate a RDMA write needs to be restarted from
620                  * an earlier PSN without interfering with the sending thread.
621                  * See restart_rc().
622                  */
623                 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
624                 /* FALLTHROUGH */
625         case OP(RDMA_WRITE_FIRST):
626                 qp->s_state = OP(RDMA_WRITE_MIDDLE);
627                 /* FALLTHROUGH */
628         case OP(RDMA_WRITE_MIDDLE):
629                 bth2 = mask_psn(qp->s_psn++);
630                 ss = &qp->s_sge;
631                 len = qp->s_len;
632                 if (len > pmtu) {
633                         len = pmtu;
634                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
635                         break;
636                 }
637                 if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
638                         qp->s_state = OP(RDMA_WRITE_LAST);
639                 } else {
640                         qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE);
641                         /* Immediate data comes after the BTH */
642                         ohdr->u.imm_data = wqe->wr.ex.imm_data;
643                         hwords += 1;
644                         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
645                                 bth0 |= IB_BTH_SOLICITED;
646                 }
647                 bth2 |= IB_BTH_REQ_ACK;
648                 qp->s_cur++;
649                 if (qp->s_cur >= qp->s_size)
650                         qp->s_cur = 0;
651                 break;
652
653         case OP(RDMA_READ_RESPONSE_MIDDLE):
654                 /*
655                  * qp->s_state is normally set to the opcode of the
656                  * last packet constructed for new requests and therefore
657                  * is never set to RDMA read response.
658                  * RDMA_READ_RESPONSE_MIDDLE is used by the ACK processing
659                  * thread to indicate a RDMA read needs to be restarted from
660                  * an earlier PSN without interfering with the sending thread.
661                  * See restart_rc().
662                  */
663                 len = (delta_psn(qp->s_psn, wqe->psn)) * pmtu;
664                 put_ib_reth_vaddr(
665                         wqe->rdma_wr.remote_addr + len,
666                         &ohdr->u.rc.reth);
667                 ohdr->u.rc.reth.rkey =
668                         cpu_to_be32(wqe->rdma_wr.rkey);
669                 ohdr->u.rc.reth.length = cpu_to_be32(wqe->length - len);
670                 qp->s_state = OP(RDMA_READ_REQUEST);
671                 hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
672                 bth2 = mask_psn(qp->s_psn) | IB_BTH_REQ_ACK;
673                 qp->s_psn = wqe->lpsn + 1;
674                 ss = NULL;
675                 len = 0;
676                 qp->s_cur++;
677                 if (qp->s_cur == qp->s_size)
678                         qp->s_cur = 0;
679                 break;
680         }
681         qp->s_sending_hpsn = bth2;
682         delta = delta_psn(bth2, wqe->psn);
683         if (delta && delta % HFI1_PSN_CREDIT == 0)
684                 bth2 |= IB_BTH_REQ_ACK;
685         if (qp->s_flags & RVT_S_SEND_ONE) {
686                 qp->s_flags &= ~RVT_S_SEND_ONE;
687                 qp->s_flags |= RVT_S_WAIT_ACK;
688                 bth2 |= IB_BTH_REQ_ACK;
689         }
690         qp->s_len -= len;
691         qp->s_hdrwords = hwords;
692         ps->s_txreq->sde = priv->s_sde;
693         ps->s_txreq->ss = ss;
694         ps->s_txreq->s_cur_size = len;
695         hfi1_make_ruc_header(
696                 qp,
697                 ohdr,
698                 bth0 | (qp->s_state << 24),
699                 bth2,
700                 middle,
701                 ps);
702         /* pbc */
703         ps->s_txreq->hdr_dwords = qp->s_hdrwords + 2;
704         return 1;
705
706 done_free_tx:
707         hfi1_put_txreq(ps->s_txreq);
708         ps->s_txreq = NULL;
709         return 1;
710
711 bail:
712         hfi1_put_txreq(ps->s_txreq);
713
714 bail_no_tx:
715         ps->s_txreq = NULL;
716         qp->s_flags &= ~RVT_S_BUSY;
717         qp->s_hdrwords = 0;
718         return 0;
719 }
720
721 static inline void hfi1_make_bth_aeth(struct rvt_qp *qp,
722                                       struct ib_other_headers *ohdr,
723                                       u32 bth0, u32 bth1)
724 {
725         if (qp->r_nak_state)
726                 ohdr->u.aeth = cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
727                                             (qp->r_nak_state <<
728                                              IB_AETH_CREDIT_SHIFT));
729         else
730                 ohdr->u.aeth = rvt_compute_aeth(qp);
731
732         ohdr->bth[0] = cpu_to_be32(bth0);
733         ohdr->bth[1] = cpu_to_be32(bth1 | qp->remote_qpn);
734         ohdr->bth[2] = cpu_to_be32(mask_psn(qp->r_ack_psn));
735 }
736
737 static inline void hfi1_queue_rc_ack(struct rvt_qp *qp, bool is_fecn)
738 {
739         struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
740         unsigned long flags;
741
742         spin_lock_irqsave(&qp->s_lock, flags);
743         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
744                 goto unlock;
745         this_cpu_inc(*ibp->rvp.rc_qacks);
746         qp->s_flags |= RVT_S_ACK_PENDING | RVT_S_RESP_PENDING;
747         qp->s_nak_state = qp->r_nak_state;
748         qp->s_ack_psn = qp->r_ack_psn;
749         if (is_fecn)
750                 qp->s_flags |= RVT_S_ECN;
751
752         /* Schedule the send tasklet. */
753         hfi1_schedule_send(qp);
754 unlock:
755         spin_unlock_irqrestore(&qp->s_lock, flags);
756 }
757
758 static inline void hfi1_make_rc_ack_9B(struct rvt_qp *qp,
759                                        struct hfi1_opa_header *opa_hdr,
760                                        u8 sc5, bool is_fecn,
761                                        u64 *pbc_flags, u32 *hwords,
762                                        u32 *nwords)
763 {
764         struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
765         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
766         struct ib_header *hdr = &opa_hdr->ibh;
767         struct ib_other_headers *ohdr;
768         u16 lrh0 = HFI1_LRH_BTH;
769         u16 pkey;
770         u32 bth0, bth1;
771
772         opa_hdr->hdr_type = HFI1_PKT_TYPE_9B;
773         ohdr = &hdr->u.oth;
774         /* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4 */
775         *hwords = 6;
776
777         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
778                 *hwords += hfi1_make_grh(ibp, &hdr->u.l.grh,
779                                          rdma_ah_read_grh(&qp->remote_ah_attr),
780                                          *hwords - 2, SIZE_OF_CRC);
781                 ohdr = &hdr->u.l.oth;
782                 lrh0 = HFI1_LRH_GRH;
783         }
784         /* set PBC_DC_INFO bit (aka SC[4]) in pbc_flags */
785         *pbc_flags |= ((!!(sc5 & 0x10)) << PBC_DC_INFO_SHIFT);
786
787         /* read pkey_index w/o lock (its atomic) */
788         pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
789
790         lrh0 |= (sc5 & IB_SC_MASK) << IB_SC_SHIFT |
791                 (rdma_ah_get_sl(&qp->remote_ah_attr) & IB_SL_MASK) <<
792                         IB_SL_SHIFT;
793
794         hfi1_make_ib_hdr(hdr, lrh0, *hwords + SIZE_OF_CRC,
795                          opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr), 9B),
796                          ppd->lid | rdma_ah_get_path_bits(&qp->remote_ah_attr));
797
798         bth0 = pkey | (OP(ACKNOWLEDGE) << 24);
799         if (qp->s_mig_state == IB_MIG_MIGRATED)
800                 bth0 |= IB_BTH_MIG_REQ;
801         bth1 = (!!is_fecn) << IB_BECN_SHIFT;
802         hfi1_make_bth_aeth(qp, ohdr, bth0, bth1);
803 }
804
805 static inline void hfi1_make_rc_ack_16B(struct rvt_qp *qp,
806                                         struct hfi1_opa_header *opa_hdr,
807                                         u8 sc5, bool is_fecn,
808                                         u64 *pbc_flags, u32 *hwords,
809                                         u32 *nwords)
810 {
811         struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
812         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
813         struct hfi1_16b_header *hdr = &opa_hdr->opah;
814         struct ib_other_headers *ohdr;
815         u32 bth0, bth1 = 0;
816         u16 len, pkey;
817         u8 becn = !!is_fecn;
818         u8 l4 = OPA_16B_L4_IB_LOCAL;
819         u8 extra_bytes;
820
821         opa_hdr->hdr_type = HFI1_PKT_TYPE_16B;
822         ohdr = &hdr->u.oth;
823         /* header size in 32-bit words 16B LRH+BTH+AETH = (16+12+4)/4 */
824         *hwords = 8;
825         extra_bytes = hfi1_get_16b_padding(*hwords << 2, 0);
826         *nwords = SIZE_OF_CRC + ((extra_bytes + SIZE_OF_LT) >> 2);
827
828         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
829             hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))) {
830                 *hwords += hfi1_make_grh(ibp, &hdr->u.l.grh,
831                                          rdma_ah_read_grh(&qp->remote_ah_attr),
832                                          *hwords - 4, *nwords);
833                 ohdr = &hdr->u.l.oth;
834                 l4 = OPA_16B_L4_IB_GLOBAL;
835         }
836         *pbc_flags |= PBC_PACKET_BYPASS | PBC_INSERT_BYPASS_ICRC;
837
838         /* read pkey_index w/o lock (its atomic) */
839         pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
840
841         /* Convert dwords to flits */
842         len = (*hwords + *nwords) >> 1;
843
844         hfi1_make_16b_hdr(hdr, ppd->lid |
845                           (rdma_ah_get_path_bits(&qp->remote_ah_attr) &
846                           ((1 << ppd->lmc) - 1)),
847                           opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr),
848                                       16B), len, pkey, becn, 0, l4, sc5);
849
850         bth0 = pkey | (OP(ACKNOWLEDGE) << 24);
851         bth0 |= extra_bytes << 20;
852         if (qp->s_mig_state == IB_MIG_MIGRATED)
853                 bth1 = OPA_BTH_MIG_REQ;
854         hfi1_make_bth_aeth(qp, ohdr, bth0, bth1);
855 }
856
857 typedef void (*hfi1_make_rc_ack)(struct rvt_qp *qp,
858                                  struct hfi1_opa_header *opa_hdr,
859                                  u8 sc5, bool is_fecn,
860                                  u64 *pbc_flags, u32 *hwords,
861                                  u32 *nwords);
862
863 /* We support only two types - 9B and 16B for now */
864 static const hfi1_make_rc_ack hfi1_make_rc_ack_tbl[2] = {
865         [HFI1_PKT_TYPE_9B] = &hfi1_make_rc_ack_9B,
866         [HFI1_PKT_TYPE_16B] = &hfi1_make_rc_ack_16B
867 };
868
869 /**
870  * hfi1_send_rc_ack - Construct an ACK packet and send it
871  * @qp: a pointer to the QP
872  *
873  * This is called from hfi1_rc_rcv() and handle_receive_interrupt().
874  * Note that RDMA reads and atomics are handled in the
875  * send side QP state and send engine.
876  */
877 void hfi1_send_rc_ack(struct hfi1_ctxtdata *rcd,
878                       struct rvt_qp *qp, bool is_fecn)
879 {
880         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
881         struct hfi1_qp_priv *priv = qp->priv;
882         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
883         u8 sc5 = ibp->sl_to_sc[rdma_ah_get_sl(&qp->remote_ah_attr)];
884         u64 pbc, pbc_flags = 0;
885         u32 hwords = 0;
886         u32 nwords = 0;
887         u32 plen;
888         struct pio_buf *pbuf;
889         struct hfi1_opa_header opa_hdr;
890
891         /* clear the defer count */
892         qp->r_adefered = 0;
893
894         /* Don't send ACK or NAK if a RDMA read or atomic is pending. */
895         if (qp->s_flags & RVT_S_RESP_PENDING) {
896                 hfi1_queue_rc_ack(qp, is_fecn);
897                 return;
898         }
899
900         /* Ensure s_rdma_ack_cnt changes are committed */
901         if (qp->s_rdma_ack_cnt) {
902                 hfi1_queue_rc_ack(qp, is_fecn);
903                 return;
904         }
905
906         /* Don't try to send ACKs if the link isn't ACTIVE */
907         if (driver_lstate(ppd) != IB_PORT_ACTIVE)
908                 return;
909
910         /* Make the appropriate header */
911         hfi1_make_rc_ack_tbl[priv->hdr_type](qp, &opa_hdr, sc5, is_fecn,
912                                              &pbc_flags, &hwords, &nwords);
913
914         plen = 2 /* PBC */ + hwords + nwords;
915         pbc = create_pbc(ppd, pbc_flags, qp->srate_mbps,
916                          sc_to_vlt(ppd->dd, sc5), plen);
917         pbuf = sc_buffer_alloc(rcd->sc, plen, NULL, NULL);
918         if (!pbuf) {
919                 /*
920                  * We have no room to send at the moment.  Pass
921                  * responsibility for sending the ACK to the send engine
922                  * so that when enough buffer space becomes available,
923                  * the ACK is sent ahead of other outgoing packets.
924                  */
925                 hfi1_queue_rc_ack(qp, is_fecn);
926                 return;
927         }
928         trace_ack_output_ibhdr(dd_from_ibdev(qp->ibqp.device),
929                                &opa_hdr, ib_is_sc5(sc5));
930
931         /* write the pbc and data */
932         ppd->dd->pio_inline_send(ppd->dd, pbuf, pbc,
933                                  (priv->hdr_type == HFI1_PKT_TYPE_9B ?
934                                  (void *)&opa_hdr.ibh :
935                                  (void *)&opa_hdr.opah), hwords);
936         return;
937 }
938
939 /**
940  * reset_psn - reset the QP state to send starting from PSN
941  * @qp: the QP
942  * @psn: the packet sequence number to restart at
943  *
944  * This is called from hfi1_rc_rcv() to process an incoming RC ACK
945  * for the given QP.
946  * Called at interrupt level with the QP s_lock held.
947  */
948 static void reset_psn(struct rvt_qp *qp, u32 psn)
949 {
950         u32 n = qp->s_acked;
951         struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, n);
952         u32 opcode;
953
954         lockdep_assert_held(&qp->s_lock);
955         qp->s_cur = n;
956
957         /*
958          * If we are starting the request from the beginning,
959          * let the normal send code handle initialization.
960          */
961         if (cmp_psn(psn, wqe->psn) <= 0) {
962                 qp->s_state = OP(SEND_LAST);
963                 goto done;
964         }
965
966         /* Find the work request opcode corresponding to the given PSN. */
967         opcode = wqe->wr.opcode;
968         for (;;) {
969                 int diff;
970
971                 if (++n == qp->s_size)
972                         n = 0;
973                 if (n == qp->s_tail)
974                         break;
975                 wqe = rvt_get_swqe_ptr(qp, n);
976                 diff = cmp_psn(psn, wqe->psn);
977                 if (diff < 0)
978                         break;
979                 qp->s_cur = n;
980                 /*
981                  * If we are starting the request from the beginning,
982                  * let the normal send code handle initialization.
983                  */
984                 if (diff == 0) {
985                         qp->s_state = OP(SEND_LAST);
986                         goto done;
987                 }
988                 opcode = wqe->wr.opcode;
989         }
990
991         /*
992          * Set the state to restart in the middle of a request.
993          * Don't change the s_sge, s_cur_sge, or s_cur_size.
994          * See hfi1_make_rc_req().
995          */
996         switch (opcode) {
997         case IB_WR_SEND:
998         case IB_WR_SEND_WITH_IMM:
999                 qp->s_state = OP(RDMA_READ_RESPONSE_FIRST);
1000                 break;
1001
1002         case IB_WR_RDMA_WRITE:
1003         case IB_WR_RDMA_WRITE_WITH_IMM:
1004                 qp->s_state = OP(RDMA_READ_RESPONSE_LAST);
1005                 break;
1006
1007         case IB_WR_RDMA_READ:
1008                 qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE);
1009                 break;
1010
1011         default:
1012                 /*
1013                  * This case shouldn't happen since its only
1014                  * one PSN per req.
1015                  */
1016                 qp->s_state = OP(SEND_LAST);
1017         }
1018 done:
1019         qp->s_psn = psn;
1020         /*
1021          * Set RVT_S_WAIT_PSN as rc_complete() may start the timer
1022          * asynchronously before the send engine can get scheduled.
1023          * Doing it in hfi1_make_rc_req() is too late.
1024          */
1025         if ((cmp_psn(qp->s_psn, qp->s_sending_hpsn) <= 0) &&
1026             (cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0))
1027                 qp->s_flags |= RVT_S_WAIT_PSN;
1028         qp->s_flags &= ~RVT_S_AHG_VALID;
1029 }
1030
1031 /*
1032  * Back up requester to resend the last un-ACKed request.
1033  * The QP r_lock and s_lock should be held and interrupts disabled.
1034  */
1035 void hfi1_restart_rc(struct rvt_qp *qp, u32 psn, int wait)
1036 {
1037         struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1038         struct hfi1_ibport *ibp;
1039
1040         lockdep_assert_held(&qp->r_lock);
1041         lockdep_assert_held(&qp->s_lock);
1042         if (qp->s_retry == 0) {
1043                 if (qp->s_mig_state == IB_MIG_ARMED) {
1044                         hfi1_migrate_qp(qp);
1045                         qp->s_retry = qp->s_retry_cnt;
1046                 } else if (qp->s_last == qp->s_acked) {
1047                         hfi1_send_complete(qp, wqe, IB_WC_RETRY_EXC_ERR);
1048                         rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1049                         return;
1050                 } else { /* need to handle delayed completion */
1051                         return;
1052                 }
1053         } else {
1054                 qp->s_retry--;
1055         }
1056
1057         ibp = to_iport(qp->ibqp.device, qp->port_num);
1058         if (wqe->wr.opcode == IB_WR_RDMA_READ)
1059                 ibp->rvp.n_rc_resends++;
1060         else
1061                 ibp->rvp.n_rc_resends += delta_psn(qp->s_psn, psn);
1062
1063         qp->s_flags &= ~(RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR |
1064                          RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_PSN |
1065                          RVT_S_WAIT_ACK);
1066         if (wait)
1067                 qp->s_flags |= RVT_S_SEND_ONE;
1068         reset_psn(qp, psn);
1069 }
1070
1071 /*
1072  * Set qp->s_sending_psn to the next PSN after the given one.
1073  * This would be psn+1 except when RDMA reads are present.
1074  */
1075 static void reset_sending_psn(struct rvt_qp *qp, u32 psn)
1076 {
1077         struct rvt_swqe *wqe;
1078         u32 n = qp->s_last;
1079
1080         lockdep_assert_held(&qp->s_lock);
1081         /* Find the work request corresponding to the given PSN. */
1082         for (;;) {
1083                 wqe = rvt_get_swqe_ptr(qp, n);
1084                 if (cmp_psn(psn, wqe->lpsn) <= 0) {
1085                         if (wqe->wr.opcode == IB_WR_RDMA_READ)
1086                                 qp->s_sending_psn = wqe->lpsn + 1;
1087                         else
1088                                 qp->s_sending_psn = psn + 1;
1089                         break;
1090                 }
1091                 if (++n == qp->s_size)
1092                         n = 0;
1093                 if (n == qp->s_tail)
1094                         break;
1095         }
1096 }
1097
1098 /*
1099  * This should be called with the QP s_lock held and interrupts disabled.
1100  */
1101 void hfi1_rc_send_complete(struct rvt_qp *qp, struct hfi1_opa_header *opah)
1102 {
1103         struct ib_other_headers *ohdr;
1104         struct hfi1_qp_priv *priv = qp->priv;
1105         struct rvt_swqe *wqe;
1106         struct ib_header *hdr = NULL;
1107         struct hfi1_16b_header *hdr_16b = NULL;
1108         u32 opcode;
1109         u32 psn;
1110
1111         lockdep_assert_held(&qp->s_lock);
1112         if (!(ib_rvt_state_ops[qp->state] & RVT_SEND_OR_FLUSH_OR_RECV_OK))
1113                 return;
1114
1115         /* Find out where the BTH is */
1116         if (priv->hdr_type == HFI1_PKT_TYPE_9B) {
1117                 hdr = &opah->ibh;
1118                 if (ib_get_lnh(hdr) == HFI1_LRH_BTH)
1119                         ohdr = &hdr->u.oth;
1120                 else
1121                         ohdr = &hdr->u.l.oth;
1122         } else {
1123                 u8 l4;
1124
1125                 hdr_16b = &opah->opah;
1126                 l4  = hfi1_16B_get_l4(hdr_16b);
1127                 if (l4 == OPA_16B_L4_IB_LOCAL)
1128                         ohdr = &hdr_16b->u.oth;
1129                 else
1130                         ohdr = &hdr_16b->u.l.oth;
1131         }
1132
1133         opcode = ib_bth_get_opcode(ohdr);
1134         if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1135             opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
1136                 WARN_ON(!qp->s_rdma_ack_cnt);
1137                 qp->s_rdma_ack_cnt--;
1138                 return;
1139         }
1140
1141         psn = ib_bth_get_psn(ohdr);
1142         reset_sending_psn(qp, psn);
1143
1144         /*
1145          * Start timer after a packet requesting an ACK has been sent and
1146          * there are still requests that haven't been acked.
1147          */
1148         if ((psn & IB_BTH_REQ_ACK) && qp->s_acked != qp->s_tail &&
1149             !(qp->s_flags &
1150                 (RVT_S_TIMER | RVT_S_WAIT_RNR | RVT_S_WAIT_PSN)) &&
1151                 (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
1152                 rvt_add_retry_timer(qp);
1153
1154         while (qp->s_last != qp->s_acked) {
1155                 u32 s_last;
1156
1157                 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
1158                 if (cmp_psn(wqe->lpsn, qp->s_sending_psn) >= 0 &&
1159                     cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)
1160                         break;
1161                 s_last = qp->s_last;
1162                 trace_hfi1_qp_send_completion(qp, wqe, s_last);
1163                 if (++s_last >= qp->s_size)
1164                         s_last = 0;
1165                 qp->s_last = s_last;
1166                 /* see post_send() */
1167                 barrier();
1168                 rvt_put_swqe(wqe);
1169                 rvt_qp_swqe_complete(qp,
1170                                      wqe,
1171                                      ib_hfi1_wc_opcode[wqe->wr.opcode],
1172                                      IB_WC_SUCCESS);
1173         }
1174         /*
1175          * If we were waiting for sends to complete before re-sending,
1176          * and they are now complete, restart sending.
1177          */
1178         trace_hfi1_sendcomplete(qp, psn);
1179         if (qp->s_flags & RVT_S_WAIT_PSN &&
1180             cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
1181                 qp->s_flags &= ~RVT_S_WAIT_PSN;
1182                 qp->s_sending_psn = qp->s_psn;
1183                 qp->s_sending_hpsn = qp->s_psn - 1;
1184                 hfi1_schedule_send(qp);
1185         }
1186 }
1187
1188 static inline void update_last_psn(struct rvt_qp *qp, u32 psn)
1189 {
1190         qp->s_last_psn = psn;
1191 }
1192
1193 /*
1194  * Generate a SWQE completion.
1195  * This is similar to hfi1_send_complete but has to check to be sure
1196  * that the SGEs are not being referenced if the SWQE is being resent.
1197  */
1198 static struct rvt_swqe *do_rc_completion(struct rvt_qp *qp,
1199                                          struct rvt_swqe *wqe,
1200                                          struct hfi1_ibport *ibp)
1201 {
1202         lockdep_assert_held(&qp->s_lock);
1203         /*
1204          * Don't decrement refcount and don't generate a
1205          * completion if the SWQE is being resent until the send
1206          * is finished.
1207          */
1208         if (cmp_psn(wqe->lpsn, qp->s_sending_psn) < 0 ||
1209             cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
1210                 u32 s_last;
1211
1212                 rvt_put_swqe(wqe);
1213                 s_last = qp->s_last;
1214                 trace_hfi1_qp_send_completion(qp, wqe, s_last);
1215                 if (++s_last >= qp->s_size)
1216                         s_last = 0;
1217                 qp->s_last = s_last;
1218                 /* see post_send() */
1219                 barrier();
1220                 rvt_qp_swqe_complete(qp,
1221                                      wqe,
1222                                      ib_hfi1_wc_opcode[wqe->wr.opcode],
1223                                      IB_WC_SUCCESS);
1224         } else {
1225                 struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1226
1227                 this_cpu_inc(*ibp->rvp.rc_delayed_comp);
1228                 /*
1229                  * If send progress not running attempt to progress
1230                  * SDMA queue.
1231                  */
1232                 if (ppd->dd->flags & HFI1_HAS_SEND_DMA) {
1233                         struct sdma_engine *engine;
1234                         u8 sl = rdma_ah_get_sl(&qp->remote_ah_attr);
1235                         u8 sc5;
1236
1237                         /* For now use sc to find engine */
1238                         sc5 = ibp->sl_to_sc[sl];
1239                         engine = qp_to_sdma_engine(qp, sc5);
1240                         sdma_engine_progress_schedule(engine);
1241                 }
1242         }
1243
1244         qp->s_retry = qp->s_retry_cnt;
1245         update_last_psn(qp, wqe->lpsn);
1246
1247         /*
1248          * If we are completing a request which is in the process of
1249          * being resent, we can stop re-sending it since we know the
1250          * responder has already seen it.
1251          */
1252         if (qp->s_acked == qp->s_cur) {
1253                 if (++qp->s_cur >= qp->s_size)
1254                         qp->s_cur = 0;
1255                 qp->s_acked = qp->s_cur;
1256                 wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
1257                 if (qp->s_acked != qp->s_tail) {
1258                         qp->s_state = OP(SEND_LAST);
1259                         qp->s_psn = wqe->psn;
1260                 }
1261         } else {
1262                 if (++qp->s_acked >= qp->s_size)
1263                         qp->s_acked = 0;
1264                 if (qp->state == IB_QPS_SQD && qp->s_acked == qp->s_cur)
1265                         qp->s_draining = 0;
1266                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1267         }
1268         return wqe;
1269 }
1270
1271 /**
1272  * do_rc_ack - process an incoming RC ACK
1273  * @qp: the QP the ACK came in on
1274  * @psn: the packet sequence number of the ACK
1275  * @opcode: the opcode of the request that resulted in the ACK
1276  *
1277  * This is called from rc_rcv_resp() to process an incoming RC ACK
1278  * for the given QP.
1279  * May be called at interrupt level, with the QP s_lock held.
1280  * Returns 1 if OK, 0 if current operation should be aborted (NAK).
1281  */
1282 static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
1283                      u64 val, struct hfi1_ctxtdata *rcd)
1284 {
1285         struct hfi1_ibport *ibp;
1286         enum ib_wc_status status;
1287         struct rvt_swqe *wqe;
1288         int ret = 0;
1289         u32 ack_psn;
1290         int diff;
1291
1292         lockdep_assert_held(&qp->s_lock);
1293         /*
1294          * Note that NAKs implicitly ACK outstanding SEND and RDMA write
1295          * requests and implicitly NAK RDMA read and atomic requests issued
1296          * before the NAK'ed request.  The MSN won't include the NAK'ed
1297          * request but will include an ACK'ed request(s).
1298          */
1299         ack_psn = psn;
1300         if (aeth >> IB_AETH_NAK_SHIFT)
1301                 ack_psn--;
1302         wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1303         ibp = rcd_to_iport(rcd);
1304
1305         /*
1306          * The MSN might be for a later WQE than the PSN indicates so
1307          * only complete WQEs that the PSN finishes.
1308          */
1309         while ((diff = delta_psn(ack_psn, wqe->lpsn)) >= 0) {
1310                 /*
1311                  * RDMA_READ_RESPONSE_ONLY is a special case since
1312                  * we want to generate completion events for everything
1313                  * before the RDMA read, copy the data, then generate
1314                  * the completion for the read.
1315                  */
1316                 if (wqe->wr.opcode == IB_WR_RDMA_READ &&
1317                     opcode == OP(RDMA_READ_RESPONSE_ONLY) &&
1318                     diff == 0) {
1319                         ret = 1;
1320                         goto bail_stop;
1321                 }
1322                 /*
1323                  * If this request is a RDMA read or atomic, and the ACK is
1324                  * for a later operation, this ACK NAKs the RDMA read or
1325                  * atomic.  In other words, only a RDMA_READ_LAST or ONLY
1326                  * can ACK a RDMA read and likewise for atomic ops.  Note
1327                  * that the NAK case can only happen if relaxed ordering is
1328                  * used and requests are sent after an RDMA read or atomic
1329                  * is sent but before the response is received.
1330                  */
1331                 if ((wqe->wr.opcode == IB_WR_RDMA_READ &&
1332                      (opcode != OP(RDMA_READ_RESPONSE_LAST) || diff != 0)) ||
1333                     ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1334                       wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) &&
1335                      (opcode != OP(ATOMIC_ACKNOWLEDGE) || diff != 0))) {
1336                         /* Retry this request. */
1337                         if (!(qp->r_flags & RVT_R_RDMAR_SEQ)) {
1338                                 qp->r_flags |= RVT_R_RDMAR_SEQ;
1339                                 hfi1_restart_rc(qp, qp->s_last_psn + 1, 0);
1340                                 if (list_empty(&qp->rspwait)) {
1341                                         qp->r_flags |= RVT_R_RSP_SEND;
1342                                         rvt_get_qp(qp);
1343                                         list_add_tail(&qp->rspwait,
1344                                                       &rcd->qp_wait_list);
1345                                 }
1346                         }
1347                         /*
1348                          * No need to process the ACK/NAK since we are
1349                          * restarting an earlier request.
1350                          */
1351                         goto bail_stop;
1352                 }
1353                 if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1354                     wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) {
1355                         u64 *vaddr = wqe->sg_list[0].vaddr;
1356                         *vaddr = val;
1357                 }
1358                 if (qp->s_num_rd_atomic &&
1359                     (wqe->wr.opcode == IB_WR_RDMA_READ ||
1360                      wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1361                      wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)) {
1362                         qp->s_num_rd_atomic--;
1363                         /* Restart sending task if fence is complete */
1364                         if ((qp->s_flags & RVT_S_WAIT_FENCE) &&
1365                             !qp->s_num_rd_atomic) {
1366                                 qp->s_flags &= ~(RVT_S_WAIT_FENCE |
1367                                                  RVT_S_WAIT_ACK);
1368                                 hfi1_schedule_send(qp);
1369                         } else if (qp->s_flags & RVT_S_WAIT_RDMAR) {
1370                                 qp->s_flags &= ~(RVT_S_WAIT_RDMAR |
1371                                                  RVT_S_WAIT_ACK);
1372                                 hfi1_schedule_send(qp);
1373                         }
1374                 }
1375                 wqe = do_rc_completion(qp, wqe, ibp);
1376                 if (qp->s_acked == qp->s_tail)
1377                         break;
1378         }
1379
1380         switch (aeth >> IB_AETH_NAK_SHIFT) {
1381         case 0:         /* ACK */
1382                 this_cpu_inc(*ibp->rvp.rc_acks);
1383                 if (qp->s_acked != qp->s_tail) {
1384                         /*
1385                          * We are expecting more ACKs so
1386                          * mod the retry timer.
1387                          */
1388                         rvt_mod_retry_timer(qp);
1389                         /*
1390                          * We can stop re-sending the earlier packets and
1391                          * continue with the next packet the receiver wants.
1392                          */
1393                         if (cmp_psn(qp->s_psn, psn) <= 0)
1394                                 reset_psn(qp, psn + 1);
1395                 } else {
1396                         /* No more acks - kill all timers */
1397                         rvt_stop_rc_timers(qp);
1398                         if (cmp_psn(qp->s_psn, psn) <= 0) {
1399                                 qp->s_state = OP(SEND_LAST);
1400                                 qp->s_psn = psn + 1;
1401                         }
1402                 }
1403                 if (qp->s_flags & RVT_S_WAIT_ACK) {
1404                         qp->s_flags &= ~RVT_S_WAIT_ACK;
1405                         hfi1_schedule_send(qp);
1406                 }
1407                 rvt_get_credit(qp, aeth);
1408                 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
1409                 qp->s_retry = qp->s_retry_cnt;
1410                 update_last_psn(qp, psn);
1411                 return 1;
1412
1413         case 1:         /* RNR NAK */
1414                 ibp->rvp.n_rnr_naks++;
1415                 if (qp->s_acked == qp->s_tail)
1416                         goto bail_stop;
1417                 if (qp->s_flags & RVT_S_WAIT_RNR)
1418                         goto bail_stop;
1419                 if (qp->s_rnr_retry == 0) {
1420                         status = IB_WC_RNR_RETRY_EXC_ERR;
1421                         goto class_b;
1422                 }
1423                 if (qp->s_rnr_retry_cnt < 7)
1424                         qp->s_rnr_retry--;
1425
1426                 /* The last valid PSN is the previous PSN. */
1427                 update_last_psn(qp, psn - 1);
1428
1429                 ibp->rvp.n_rc_resends += delta_psn(qp->s_psn, psn);
1430
1431                 reset_psn(qp, psn);
1432
1433                 qp->s_flags &= ~(RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_ACK);
1434                 rvt_stop_rc_timers(qp);
1435                 rvt_add_rnr_timer(qp, aeth);
1436                 return 0;
1437
1438         case 3:         /* NAK */
1439                 if (qp->s_acked == qp->s_tail)
1440                         goto bail_stop;
1441                 /* The last valid PSN is the previous PSN. */
1442                 update_last_psn(qp, psn - 1);
1443                 switch ((aeth >> IB_AETH_CREDIT_SHIFT) &
1444                         IB_AETH_CREDIT_MASK) {
1445                 case 0: /* PSN sequence error */
1446                         ibp->rvp.n_seq_naks++;
1447                         /*
1448                          * Back up to the responder's expected PSN.
1449                          * Note that we might get a NAK in the middle of an
1450                          * RDMA READ response which terminates the RDMA
1451                          * READ.
1452                          */
1453                         hfi1_restart_rc(qp, psn, 0);
1454                         hfi1_schedule_send(qp);
1455                         break;
1456
1457                 case 1: /* Invalid Request */
1458                         status = IB_WC_REM_INV_REQ_ERR;
1459                         ibp->rvp.n_other_naks++;
1460                         goto class_b;
1461
1462                 case 2: /* Remote Access Error */
1463                         status = IB_WC_REM_ACCESS_ERR;
1464                         ibp->rvp.n_other_naks++;
1465                         goto class_b;
1466
1467                 case 3: /* Remote Operation Error */
1468                         status = IB_WC_REM_OP_ERR;
1469                         ibp->rvp.n_other_naks++;
1470 class_b:
1471                         if (qp->s_last == qp->s_acked) {
1472                                 hfi1_send_complete(qp, wqe, status);
1473                                 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1474                         }
1475                         break;
1476
1477                 default:
1478                         /* Ignore other reserved NAK error codes */
1479                         goto reserved;
1480                 }
1481                 qp->s_retry = qp->s_retry_cnt;
1482                 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
1483                 goto bail_stop;
1484
1485         default:                /* 2: reserved */
1486 reserved:
1487                 /* Ignore reserved NAK codes. */
1488                 goto bail_stop;
1489         }
1490         /* cannot be reached  */
1491 bail_stop:
1492         rvt_stop_rc_timers(qp);
1493         return ret;
1494 }
1495
1496 /*
1497  * We have seen an out of sequence RDMA read middle or last packet.
1498  * This ACKs SENDs and RDMA writes up to the first RDMA read or atomic SWQE.
1499  */
1500 static void rdma_seq_err(struct rvt_qp *qp, struct hfi1_ibport *ibp, u32 psn,
1501                          struct hfi1_ctxtdata *rcd)
1502 {
1503         struct rvt_swqe *wqe;
1504
1505         lockdep_assert_held(&qp->s_lock);
1506         /* Remove QP from retry timer */
1507         rvt_stop_rc_timers(qp);
1508
1509         wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1510
1511         while (cmp_psn(psn, wqe->lpsn) > 0) {
1512                 if (wqe->wr.opcode == IB_WR_RDMA_READ ||
1513                     wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1514                     wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)
1515                         break;
1516                 wqe = do_rc_completion(qp, wqe, ibp);
1517         }
1518
1519         ibp->rvp.n_rdma_seq++;
1520         qp->r_flags |= RVT_R_RDMAR_SEQ;
1521         hfi1_restart_rc(qp, qp->s_last_psn + 1, 0);
1522         if (list_empty(&qp->rspwait)) {
1523                 qp->r_flags |= RVT_R_RSP_SEND;
1524                 rvt_get_qp(qp);
1525                 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
1526         }
1527 }
1528
1529 /**
1530  * rc_rcv_resp - process an incoming RC response packet
1531  * @packet: data packet information
1532  *
1533  * This is called from hfi1_rc_rcv() to process an incoming RC response
1534  * packet for the given QP.
1535  * Called at interrupt level.
1536  */
1537 static void rc_rcv_resp(struct hfi1_packet *packet)
1538 {
1539         struct hfi1_ctxtdata *rcd = packet->rcd;
1540         void *data = packet->payload;
1541         u32 tlen = packet->tlen;
1542         struct rvt_qp *qp = packet->qp;
1543         struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
1544         struct ib_other_headers *ohdr = packet->ohdr;
1545         struct rvt_swqe *wqe;
1546         enum ib_wc_status status;
1547         unsigned long flags;
1548         int diff;
1549         u64 val;
1550         u32 aeth;
1551         u32 psn = ib_bth_get_psn(packet->ohdr);
1552         u32 pmtu = qp->pmtu;
1553         u16 hdrsize = packet->hlen;
1554         u8 opcode = packet->opcode;
1555         u8 pad = packet->pad;
1556         u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
1557
1558         spin_lock_irqsave(&qp->s_lock, flags);
1559         trace_hfi1_ack(qp, psn);
1560
1561         /* Ignore invalid responses. */
1562         if (cmp_psn(psn, READ_ONCE(qp->s_next_psn)) >= 0)
1563                 goto ack_done;
1564
1565         /* Ignore duplicate responses. */
1566         diff = cmp_psn(psn, qp->s_last_psn);
1567         if (unlikely(diff <= 0)) {
1568                 /* Update credits for "ghost" ACKs */
1569                 if (diff == 0 && opcode == OP(ACKNOWLEDGE)) {
1570                         aeth = be32_to_cpu(ohdr->u.aeth);
1571                         if ((aeth >> IB_AETH_NAK_SHIFT) == 0)
1572                                 rvt_get_credit(qp, aeth);
1573                 }
1574                 goto ack_done;
1575         }
1576
1577         /*
1578          * Skip everything other than the PSN we expect, if we are waiting
1579          * for a reply to a restarted RDMA read or atomic op.
1580          */
1581         if (qp->r_flags & RVT_R_RDMAR_SEQ) {
1582                 if (cmp_psn(psn, qp->s_last_psn + 1) != 0)
1583                         goto ack_done;
1584                 qp->r_flags &= ~RVT_R_RDMAR_SEQ;
1585         }
1586
1587         if (unlikely(qp->s_acked == qp->s_tail))
1588                 goto ack_done;
1589         wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1590         status = IB_WC_SUCCESS;
1591
1592         switch (opcode) {
1593         case OP(ACKNOWLEDGE):
1594         case OP(ATOMIC_ACKNOWLEDGE):
1595         case OP(RDMA_READ_RESPONSE_FIRST):
1596                 aeth = be32_to_cpu(ohdr->u.aeth);
1597                 if (opcode == OP(ATOMIC_ACKNOWLEDGE))
1598                         val = ib_u64_get(&ohdr->u.at.atomic_ack_eth);
1599                 else
1600                         val = 0;
1601                 if (!do_rc_ack(qp, aeth, psn, opcode, val, rcd) ||
1602                     opcode != OP(RDMA_READ_RESPONSE_FIRST))
1603                         goto ack_done;
1604                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1605                 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
1606                         goto ack_op_err;
1607                 /*
1608                  * If this is a response to a resent RDMA read, we
1609                  * have to be careful to copy the data to the right
1610                  * location.
1611                  */
1612                 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
1613                                                   wqe, psn, pmtu);
1614                 goto read_middle;
1615
1616         case OP(RDMA_READ_RESPONSE_MIDDLE):
1617                 /* no AETH, no ACK */
1618                 if (unlikely(cmp_psn(psn, qp->s_last_psn + 1)))
1619                         goto ack_seq_err;
1620                 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
1621                         goto ack_op_err;
1622 read_middle:
1623                 if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
1624                         goto ack_len_err;
1625                 if (unlikely(pmtu >= qp->s_rdma_read_len))
1626                         goto ack_len_err;
1627
1628                 /*
1629                  * We got a response so update the timeout.
1630                  * 4.096 usec. * (1 << qp->timeout)
1631                  */
1632                 rvt_mod_retry_timer(qp);
1633                 if (qp->s_flags & RVT_S_WAIT_ACK) {
1634                         qp->s_flags &= ~RVT_S_WAIT_ACK;
1635                         hfi1_schedule_send(qp);
1636                 }
1637
1638                 if (opcode == OP(RDMA_READ_RESPONSE_MIDDLE))
1639                         qp->s_retry = qp->s_retry_cnt;
1640
1641                 /*
1642                  * Update the RDMA receive state but do the copy w/o
1643                  * holding the locks and blocking interrupts.
1644                  */
1645                 qp->s_rdma_read_len -= pmtu;
1646                 update_last_psn(qp, psn);
1647                 spin_unlock_irqrestore(&qp->s_lock, flags);
1648                 hfi1_copy_sge(&qp->s_rdma_read_sge, data, pmtu, false, false);
1649                 goto bail;
1650
1651         case OP(RDMA_READ_RESPONSE_ONLY):
1652                 aeth = be32_to_cpu(ohdr->u.aeth);
1653                 if (!do_rc_ack(qp, aeth, psn, opcode, 0, rcd))
1654                         goto ack_done;
1655                 /*
1656                  * Check that the data size is >= 0 && <= pmtu.
1657                  * Remember to account for ICRC (4).
1658                  */
1659                 if (unlikely(tlen < (hdrsize + extra_bytes)))
1660                         goto ack_len_err;
1661                 /*
1662                  * If this is a response to a resent RDMA read, we
1663                  * have to be careful to copy the data to the right
1664                  * location.
1665                  */
1666                 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1667                 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
1668                                                   wqe, psn, pmtu);
1669                 goto read_last;
1670
1671         case OP(RDMA_READ_RESPONSE_LAST):
1672                 /* ACKs READ req. */
1673                 if (unlikely(cmp_psn(psn, qp->s_last_psn + 1)))
1674                         goto ack_seq_err;
1675                 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
1676                         goto ack_op_err;
1677                 /*
1678                  * Check that the data size is >= 1 && <= pmtu.
1679                  * Remember to account for ICRC (4).
1680                  */
1681                 if (unlikely(tlen <= (hdrsize + extra_bytes)))
1682                         goto ack_len_err;
1683 read_last:
1684                 tlen -= hdrsize + extra_bytes;
1685                 if (unlikely(tlen != qp->s_rdma_read_len))
1686                         goto ack_len_err;
1687                 aeth = be32_to_cpu(ohdr->u.aeth);
1688                 hfi1_copy_sge(&qp->s_rdma_read_sge, data, tlen, false, false);
1689                 WARN_ON(qp->s_rdma_read_sge.num_sge);
1690                 (void)do_rc_ack(qp, aeth, psn,
1691                                  OP(RDMA_READ_RESPONSE_LAST), 0, rcd);
1692                 goto ack_done;
1693         }
1694
1695 ack_op_err:
1696         status = IB_WC_LOC_QP_OP_ERR;
1697         goto ack_err;
1698
1699 ack_seq_err:
1700         rdma_seq_err(qp, ibp, psn, rcd);
1701         goto ack_done;
1702
1703 ack_len_err:
1704         status = IB_WC_LOC_LEN_ERR;
1705 ack_err:
1706         if (qp->s_last == qp->s_acked) {
1707                 hfi1_send_complete(qp, wqe, status);
1708                 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1709         }
1710 ack_done:
1711         spin_unlock_irqrestore(&qp->s_lock, flags);
1712 bail:
1713         return;
1714 }
1715
1716 static inline void rc_defered_ack(struct hfi1_ctxtdata *rcd,
1717                                   struct rvt_qp *qp)
1718 {
1719         if (list_empty(&qp->rspwait)) {
1720                 qp->r_flags |= RVT_R_RSP_NAK;
1721                 rvt_get_qp(qp);
1722                 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
1723         }
1724 }
1725
1726 static inline void rc_cancel_ack(struct rvt_qp *qp)
1727 {
1728         qp->r_adefered = 0;
1729         if (list_empty(&qp->rspwait))
1730                 return;
1731         list_del_init(&qp->rspwait);
1732         qp->r_flags &= ~RVT_R_RSP_NAK;
1733         rvt_put_qp(qp);
1734 }
1735
1736 /**
1737  * rc_rcv_error - process an incoming duplicate or error RC packet
1738  * @ohdr: the other headers for this packet
1739  * @data: the packet data
1740  * @qp: the QP for this packet
1741  * @opcode: the opcode for this packet
1742  * @psn: the packet sequence number for this packet
1743  * @diff: the difference between the PSN and the expected PSN
1744  *
1745  * This is called from hfi1_rc_rcv() to process an unexpected
1746  * incoming RC packet for the given QP.
1747  * Called at interrupt level.
1748  * Return 1 if no more processing is needed; otherwise return 0 to
1749  * schedule a response to be sent.
1750  */
1751 static noinline int rc_rcv_error(struct ib_other_headers *ohdr, void *data,
1752                                  struct rvt_qp *qp, u32 opcode, u32 psn,
1753                                  int diff, struct hfi1_ctxtdata *rcd)
1754 {
1755         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
1756         struct rvt_ack_entry *e;
1757         unsigned long flags;
1758         u8 i, prev;
1759         int old_req;
1760
1761         trace_hfi1_rcv_error(qp, psn);
1762         if (diff > 0) {
1763                 /*
1764                  * Packet sequence error.
1765                  * A NAK will ACK earlier sends and RDMA writes.
1766                  * Don't queue the NAK if we already sent one.
1767                  */
1768                 if (!qp->r_nak_state) {
1769                         ibp->rvp.n_rc_seqnak++;
1770                         qp->r_nak_state = IB_NAK_PSN_ERROR;
1771                         /* Use the expected PSN. */
1772                         qp->r_ack_psn = qp->r_psn;
1773                         /*
1774                          * Wait to send the sequence NAK until all packets
1775                          * in the receive queue have been processed.
1776                          * Otherwise, we end up propagating congestion.
1777                          */
1778                         rc_defered_ack(rcd, qp);
1779                 }
1780                 goto done;
1781         }
1782
1783         /*
1784          * Handle a duplicate request.  Don't re-execute SEND, RDMA
1785          * write or atomic op.  Don't NAK errors, just silently drop
1786          * the duplicate request.  Note that r_sge, r_len, and
1787          * r_rcv_len may be in use so don't modify them.
1788          *
1789          * We are supposed to ACK the earliest duplicate PSN but we
1790          * can coalesce an outstanding duplicate ACK.  We have to
1791          * send the earliest so that RDMA reads can be restarted at
1792          * the requester's expected PSN.
1793          *
1794          * First, find where this duplicate PSN falls within the
1795          * ACKs previously sent.
1796          * old_req is true if there is an older response that is scheduled
1797          * to be sent before sending this one.
1798          */
1799         e = NULL;
1800         old_req = 1;
1801         ibp->rvp.n_rc_dupreq++;
1802
1803         spin_lock_irqsave(&qp->s_lock, flags);
1804
1805         for (i = qp->r_head_ack_queue; ; i = prev) {
1806                 if (i == qp->s_tail_ack_queue)
1807                         old_req = 0;
1808                 if (i)
1809                         prev = i - 1;
1810                 else
1811                         prev = HFI1_MAX_RDMA_ATOMIC;
1812                 if (prev == qp->r_head_ack_queue) {
1813                         e = NULL;
1814                         break;
1815                 }
1816                 e = &qp->s_ack_queue[prev];
1817                 if (!e->opcode) {
1818                         e = NULL;
1819                         break;
1820                 }
1821                 if (cmp_psn(psn, e->psn) >= 0) {
1822                         if (prev == qp->s_tail_ack_queue &&
1823                             cmp_psn(psn, e->lpsn) <= 0)
1824                                 old_req = 0;
1825                         break;
1826                 }
1827         }
1828         switch (opcode) {
1829         case OP(RDMA_READ_REQUEST): {
1830                 struct ib_reth *reth;
1831                 u32 offset;
1832                 u32 len;
1833
1834                 /*
1835                  * If we didn't find the RDMA read request in the ack queue,
1836                  * we can ignore this request.
1837                  */
1838                 if (!e || e->opcode != OP(RDMA_READ_REQUEST))
1839                         goto unlock_done;
1840                 /* RETH comes after BTH */
1841                 reth = &ohdr->u.rc.reth;
1842                 /*
1843                  * Address range must be a subset of the original
1844                  * request and start on pmtu boundaries.
1845                  * We reuse the old ack_queue slot since the requester
1846                  * should not back up and request an earlier PSN for the
1847                  * same request.
1848                  */
1849                 offset = delta_psn(psn, e->psn) * qp->pmtu;
1850                 len = be32_to_cpu(reth->length);
1851                 if (unlikely(offset + len != e->rdma_sge.sge_length))
1852                         goto unlock_done;
1853                 if (e->rdma_sge.mr) {
1854                         rvt_put_mr(e->rdma_sge.mr);
1855                         e->rdma_sge.mr = NULL;
1856                 }
1857                 if (len != 0) {
1858                         u32 rkey = be32_to_cpu(reth->rkey);
1859                         u64 vaddr = get_ib_reth_vaddr(reth);
1860                         int ok;
1861
1862                         ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey,
1863                                          IB_ACCESS_REMOTE_READ);
1864                         if (unlikely(!ok))
1865                                 goto unlock_done;
1866                 } else {
1867                         e->rdma_sge.vaddr = NULL;
1868                         e->rdma_sge.length = 0;
1869                         e->rdma_sge.sge_length = 0;
1870                 }
1871                 e->psn = psn;
1872                 if (old_req)
1873                         goto unlock_done;
1874                 qp->s_tail_ack_queue = prev;
1875                 break;
1876         }
1877
1878         case OP(COMPARE_SWAP):
1879         case OP(FETCH_ADD): {
1880                 /*
1881                  * If we didn't find the atomic request in the ack queue
1882                  * or the send engine is already backed up to send an
1883                  * earlier entry, we can ignore this request.
1884                  */
1885                 if (!e || e->opcode != (u8)opcode || old_req)
1886                         goto unlock_done;
1887                 qp->s_tail_ack_queue = prev;
1888                 break;
1889         }
1890
1891         default:
1892                 /*
1893                  * Ignore this operation if it doesn't request an ACK
1894                  * or an earlier RDMA read or atomic is going to be resent.
1895                  */
1896                 if (!(psn & IB_BTH_REQ_ACK) || old_req)
1897                         goto unlock_done;
1898                 /*
1899                  * Resend the most recent ACK if this request is
1900                  * after all the previous RDMA reads and atomics.
1901                  */
1902                 if (i == qp->r_head_ack_queue) {
1903                         spin_unlock_irqrestore(&qp->s_lock, flags);
1904                         qp->r_nak_state = 0;
1905                         qp->r_ack_psn = qp->r_psn - 1;
1906                         goto send_ack;
1907                 }
1908
1909                 /*
1910                  * Resend the RDMA read or atomic op which
1911                  * ACKs this duplicate request.
1912                  */
1913                 qp->s_tail_ack_queue = i;
1914                 break;
1915         }
1916         qp->s_ack_state = OP(ACKNOWLEDGE);
1917         qp->s_flags |= RVT_S_RESP_PENDING;
1918         qp->r_nak_state = 0;
1919         hfi1_schedule_send(qp);
1920
1921 unlock_done:
1922         spin_unlock_irqrestore(&qp->s_lock, flags);
1923 done:
1924         return 1;
1925
1926 send_ack:
1927         return 0;
1928 }
1929
1930 static inline void update_ack_queue(struct rvt_qp *qp, unsigned n)
1931 {
1932         unsigned next;
1933
1934         next = n + 1;
1935         if (next > HFI1_MAX_RDMA_ATOMIC)
1936                 next = 0;
1937         qp->s_tail_ack_queue = next;
1938         qp->s_ack_state = OP(ACKNOWLEDGE);
1939 }
1940
1941 static void log_cca_event(struct hfi1_pportdata *ppd, u8 sl, u32 rlid,
1942                           u32 lqpn, u32 rqpn, u8 svc_type)
1943 {
1944         struct opa_hfi1_cong_log_event_internal *cc_event;
1945         unsigned long flags;
1946
1947         if (sl >= OPA_MAX_SLS)
1948                 return;
1949
1950         spin_lock_irqsave(&ppd->cc_log_lock, flags);
1951
1952         ppd->threshold_cong_event_map[sl / 8] |= 1 << (sl % 8);
1953         ppd->threshold_event_counter++;
1954
1955         cc_event = &ppd->cc_events[ppd->cc_log_idx++];
1956         if (ppd->cc_log_idx == OPA_CONG_LOG_ELEMS)
1957                 ppd->cc_log_idx = 0;
1958         cc_event->lqpn = lqpn & RVT_QPN_MASK;
1959         cc_event->rqpn = rqpn & RVT_QPN_MASK;
1960         cc_event->sl = sl;
1961         cc_event->svc_type = svc_type;
1962         cc_event->rlid = rlid;
1963         /* keep timestamp in units of 1.024 usec */
1964         cc_event->timestamp = ktime_get_ns() / 1024;
1965
1966         spin_unlock_irqrestore(&ppd->cc_log_lock, flags);
1967 }
1968
1969 void process_becn(struct hfi1_pportdata *ppd, u8 sl, u32 rlid, u32 lqpn,
1970                   u32 rqpn, u8 svc_type)
1971 {
1972         struct cca_timer *cca_timer;
1973         u16 ccti, ccti_incr, ccti_timer, ccti_limit;
1974         u8 trigger_threshold;
1975         struct cc_state *cc_state;
1976         unsigned long flags;
1977
1978         if (sl >= OPA_MAX_SLS)
1979                 return;
1980
1981         cc_state = get_cc_state(ppd);
1982
1983         if (!cc_state)
1984                 return;
1985
1986         /*
1987          * 1) increase CCTI (for this SL)
1988          * 2) select IPG (i.e., call set_link_ipg())
1989          * 3) start timer
1990          */
1991         ccti_limit = cc_state->cct.ccti_limit;
1992         ccti_incr = cc_state->cong_setting.entries[sl].ccti_increase;
1993         ccti_timer = cc_state->cong_setting.entries[sl].ccti_timer;
1994         trigger_threshold =
1995                 cc_state->cong_setting.entries[sl].trigger_threshold;
1996
1997         spin_lock_irqsave(&ppd->cca_timer_lock, flags);
1998
1999         cca_timer = &ppd->cca_timer[sl];
2000         if (cca_timer->ccti < ccti_limit) {
2001                 if (cca_timer->ccti + ccti_incr <= ccti_limit)
2002                         cca_timer->ccti += ccti_incr;
2003                 else
2004                         cca_timer->ccti = ccti_limit;
2005                 set_link_ipg(ppd);
2006         }
2007
2008         ccti = cca_timer->ccti;
2009
2010         if (!hrtimer_active(&cca_timer->hrtimer)) {
2011                 /* ccti_timer is in units of 1.024 usec */
2012                 unsigned long nsec = 1024 * ccti_timer;
2013
2014                 hrtimer_start(&cca_timer->hrtimer, ns_to_ktime(nsec),
2015                               HRTIMER_MODE_REL);
2016         }
2017
2018         spin_unlock_irqrestore(&ppd->cca_timer_lock, flags);
2019
2020         if ((trigger_threshold != 0) && (ccti >= trigger_threshold))
2021                 log_cca_event(ppd, sl, rlid, lqpn, rqpn, svc_type);
2022 }
2023
2024 /**
2025  * hfi1_rc_rcv - process an incoming RC packet
2026  * @packet: data packet information
2027  *
2028  * This is called from qp_rcv() to process an incoming RC packet
2029  * for the given QP.
2030  * May be called at interrupt level.
2031  */
2032 void hfi1_rc_rcv(struct hfi1_packet *packet)
2033 {
2034         struct hfi1_ctxtdata *rcd = packet->rcd;
2035         void *data = packet->payload;
2036         u32 tlen = packet->tlen;
2037         struct rvt_qp *qp = packet->qp;
2038         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
2039         struct ib_other_headers *ohdr = packet->ohdr;
2040         u32 bth0 = be32_to_cpu(ohdr->bth[0]);
2041         u32 opcode = packet->opcode;
2042         u32 hdrsize = packet->hlen;
2043         u32 psn = ib_bth_get_psn(packet->ohdr);
2044         u32 pad = packet->pad;
2045         struct ib_wc wc;
2046         u32 pmtu = qp->pmtu;
2047         int diff;
2048         struct ib_reth *reth;
2049         unsigned long flags;
2050         int ret;
2051         bool is_fecn = false;
2052         bool copy_last = false;
2053         u32 rkey;
2054         u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
2055
2056         lockdep_assert_held(&qp->r_lock);
2057
2058         if (hfi1_ruc_check_hdr(ibp, packet))
2059                 return;
2060
2061         is_fecn = process_ecn(qp, packet, false);
2062
2063         /*
2064          * Process responses (ACKs) before anything else.  Note that the
2065          * packet sequence number will be for something in the send work
2066          * queue rather than the expected receive packet sequence number.
2067          * In other words, this QP is the requester.
2068          */
2069         if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
2070             opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
2071                 rc_rcv_resp(packet);
2072                 if (is_fecn)
2073                         goto send_ack;
2074                 return;
2075         }
2076
2077         /* Compute 24 bits worth of difference. */
2078         diff = delta_psn(psn, qp->r_psn);
2079         if (unlikely(diff)) {
2080                 if (rc_rcv_error(ohdr, data, qp, opcode, psn, diff, rcd))
2081                         return;
2082                 goto send_ack;
2083         }
2084
2085         /* Check for opcode sequence errors. */
2086         switch (qp->r_state) {
2087         case OP(SEND_FIRST):
2088         case OP(SEND_MIDDLE):
2089                 if (opcode == OP(SEND_MIDDLE) ||
2090                     opcode == OP(SEND_LAST) ||
2091                     opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
2092                     opcode == OP(SEND_LAST_WITH_INVALIDATE))
2093                         break;
2094                 goto nack_inv;
2095
2096         case OP(RDMA_WRITE_FIRST):
2097         case OP(RDMA_WRITE_MIDDLE):
2098                 if (opcode == OP(RDMA_WRITE_MIDDLE) ||
2099                     opcode == OP(RDMA_WRITE_LAST) ||
2100                     opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
2101                         break;
2102                 goto nack_inv;
2103
2104         default:
2105                 if (opcode == OP(SEND_MIDDLE) ||
2106                     opcode == OP(SEND_LAST) ||
2107                     opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
2108                     opcode == OP(SEND_LAST_WITH_INVALIDATE) ||
2109                     opcode == OP(RDMA_WRITE_MIDDLE) ||
2110                     opcode == OP(RDMA_WRITE_LAST) ||
2111                     opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
2112                         goto nack_inv;
2113                 /*
2114                  * Note that it is up to the requester to not send a new
2115                  * RDMA read or atomic operation before receiving an ACK
2116                  * for the previous operation.
2117                  */
2118                 break;
2119         }
2120
2121         if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST))
2122                 rvt_comm_est(qp);
2123
2124         /* OK, process the packet. */
2125         switch (opcode) {
2126         case OP(SEND_FIRST):
2127                 ret = hfi1_rvt_get_rwqe(qp, 0);
2128                 if (ret < 0)
2129                         goto nack_op_err;
2130                 if (!ret)
2131                         goto rnr_nak;
2132                 qp->r_rcv_len = 0;
2133                 /* FALLTHROUGH */
2134         case OP(SEND_MIDDLE):
2135         case OP(RDMA_WRITE_MIDDLE):
2136 send_middle:
2137                 /* Check for invalid length PMTU or posted rwqe len. */
2138                 /*
2139                  * There will be no padding for 9B packet but 16B packets
2140                  * will come in with some padding since we always add
2141                  * CRC and LT bytes which will need to be flit aligned
2142                  */
2143                 if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
2144                         goto nack_inv;
2145                 qp->r_rcv_len += pmtu;
2146                 if (unlikely(qp->r_rcv_len > qp->r_len))
2147                         goto nack_inv;
2148                 hfi1_copy_sge(&qp->r_sge, data, pmtu, true, false);
2149                 break;
2150
2151         case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
2152                 /* consume RWQE */
2153                 ret = hfi1_rvt_get_rwqe(qp, 1);
2154                 if (ret < 0)
2155                         goto nack_op_err;
2156                 if (!ret)
2157                         goto rnr_nak;
2158                 goto send_last_imm;
2159
2160         case OP(SEND_ONLY):
2161         case OP(SEND_ONLY_WITH_IMMEDIATE):
2162         case OP(SEND_ONLY_WITH_INVALIDATE):
2163                 ret = hfi1_rvt_get_rwqe(qp, 0);
2164                 if (ret < 0)
2165                         goto nack_op_err;
2166                 if (!ret)
2167                         goto rnr_nak;
2168                 qp->r_rcv_len = 0;
2169                 if (opcode == OP(SEND_ONLY))
2170                         goto no_immediate_data;
2171                 if (opcode == OP(SEND_ONLY_WITH_INVALIDATE))
2172                         goto send_last_inv;
2173                 /* FALLTHROUGH -- for SEND_ONLY_WITH_IMMEDIATE */
2174         case OP(SEND_LAST_WITH_IMMEDIATE):
2175 send_last_imm:
2176                 wc.ex.imm_data = ohdr->u.imm_data;
2177                 wc.wc_flags = IB_WC_WITH_IMM;
2178                 goto send_last;
2179         case OP(SEND_LAST_WITH_INVALIDATE):
2180 send_last_inv:
2181                 rkey = be32_to_cpu(ohdr->u.ieth);
2182                 if (rvt_invalidate_rkey(qp, rkey))
2183                         goto no_immediate_data;
2184                 wc.ex.invalidate_rkey = rkey;
2185                 wc.wc_flags = IB_WC_WITH_INVALIDATE;
2186                 goto send_last;
2187         case OP(RDMA_WRITE_LAST):
2188                 copy_last = rvt_is_user_qp(qp);
2189                 /* fall through */
2190         case OP(SEND_LAST):
2191 no_immediate_data:
2192                 wc.wc_flags = 0;
2193                 wc.ex.imm_data = 0;
2194 send_last:
2195                 /* Check for invalid length. */
2196                 /* LAST len should be >= 1 */
2197                 if (unlikely(tlen < (hdrsize + extra_bytes)))
2198                         goto nack_inv;
2199                 /* Don't count the CRC(and padding and LT byte for 16B). */
2200                 tlen -= (hdrsize + extra_bytes);
2201                 wc.byte_len = tlen + qp->r_rcv_len;
2202                 if (unlikely(wc.byte_len > qp->r_len))
2203                         goto nack_inv;
2204                 hfi1_copy_sge(&qp->r_sge, data, tlen, true, copy_last);
2205                 rvt_put_ss(&qp->r_sge);
2206                 qp->r_msn++;
2207                 if (!__test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
2208                         break;
2209                 wc.wr_id = qp->r_wr_id;
2210                 wc.status = IB_WC_SUCCESS;
2211                 if (opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE) ||
2212                     opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
2213                         wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
2214                 else
2215                         wc.opcode = IB_WC_RECV;
2216                 wc.qp = &qp->ibqp;
2217                 wc.src_qp = qp->remote_qpn;
2218                 wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
2219                 /*
2220                  * It seems that IB mandates the presence of an SL in a
2221                  * work completion only for the UD transport (see section
2222                  * 11.4.2 of IBTA Vol. 1).
2223                  *
2224                  * However, the way the SL is chosen below is consistent
2225                  * with the way that IB/qib works and is trying avoid
2226                  * introducing incompatibilities.
2227                  *
2228                  * See also OPA Vol. 1, section 9.7.6, and table 9-17.
2229                  */
2230                 wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
2231                 /* zero fields that are N/A */
2232                 wc.vendor_err = 0;
2233                 wc.pkey_index = 0;
2234                 wc.dlid_path_bits = 0;
2235                 wc.port_num = 0;
2236                 /* Signal completion event if the solicited bit is set. */
2237                 rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
2238                              (bth0 & IB_BTH_SOLICITED) != 0);
2239                 break;
2240
2241         case OP(RDMA_WRITE_ONLY):
2242                 copy_last = rvt_is_user_qp(qp);
2243                 /* fall through */
2244         case OP(RDMA_WRITE_FIRST):
2245         case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
2246                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
2247                         goto nack_inv;
2248                 /* consume RWQE */
2249                 reth = &ohdr->u.rc.reth;
2250                 qp->r_len = be32_to_cpu(reth->length);
2251                 qp->r_rcv_len = 0;
2252                 qp->r_sge.sg_list = NULL;
2253                 if (qp->r_len != 0) {
2254                         u32 rkey = be32_to_cpu(reth->rkey);
2255                         u64 vaddr = get_ib_reth_vaddr(reth);
2256                         int ok;
2257
2258                         /* Check rkey & NAK */
2259                         ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len, vaddr,
2260                                          rkey, IB_ACCESS_REMOTE_WRITE);
2261                         if (unlikely(!ok))
2262                                 goto nack_acc;
2263                         qp->r_sge.num_sge = 1;
2264                 } else {
2265                         qp->r_sge.num_sge = 0;
2266                         qp->r_sge.sge.mr = NULL;
2267                         qp->r_sge.sge.vaddr = NULL;
2268                         qp->r_sge.sge.length = 0;
2269                         qp->r_sge.sge.sge_length = 0;
2270                 }
2271                 if (opcode == OP(RDMA_WRITE_FIRST))
2272                         goto send_middle;
2273                 else if (opcode == OP(RDMA_WRITE_ONLY))
2274                         goto no_immediate_data;
2275                 ret = hfi1_rvt_get_rwqe(qp, 1);
2276                 if (ret < 0)
2277                         goto nack_op_err;
2278                 if (!ret) {
2279                         /* peer will send again */
2280                         rvt_put_ss(&qp->r_sge);
2281                         goto rnr_nak;
2282                 }
2283                 wc.ex.imm_data = ohdr->u.rc.imm_data;
2284                 wc.wc_flags = IB_WC_WITH_IMM;
2285                 goto send_last;
2286
2287         case OP(RDMA_READ_REQUEST): {
2288                 struct rvt_ack_entry *e;
2289                 u32 len;
2290                 u8 next;
2291
2292                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
2293                         goto nack_inv;
2294                 next = qp->r_head_ack_queue + 1;
2295                 /* s_ack_queue is size HFI1_MAX_RDMA_ATOMIC+1 so use > not >= */
2296                 if (next > HFI1_MAX_RDMA_ATOMIC)
2297                         next = 0;
2298                 spin_lock_irqsave(&qp->s_lock, flags);
2299                 if (unlikely(next == qp->s_tail_ack_queue)) {
2300                         if (!qp->s_ack_queue[next].sent)
2301                                 goto nack_inv_unlck;
2302                         update_ack_queue(qp, next);
2303                 }
2304                 e = &qp->s_ack_queue[qp->r_head_ack_queue];
2305                 if (e->opcode == OP(RDMA_READ_REQUEST) && e->rdma_sge.mr) {
2306                         rvt_put_mr(e->rdma_sge.mr);
2307                         e->rdma_sge.mr = NULL;
2308                 }
2309                 reth = &ohdr->u.rc.reth;
2310                 len = be32_to_cpu(reth->length);
2311                 if (len) {
2312                         u32 rkey = be32_to_cpu(reth->rkey);
2313                         u64 vaddr = get_ib_reth_vaddr(reth);
2314                         int ok;
2315
2316                         /* Check rkey & NAK */
2317                         ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr,
2318                                          rkey, IB_ACCESS_REMOTE_READ);
2319                         if (unlikely(!ok))
2320                                 goto nack_acc_unlck;
2321                         /*
2322                          * Update the next expected PSN.  We add 1 later
2323                          * below, so only add the remainder here.
2324                          */
2325                         qp->r_psn += rvt_div_mtu(qp, len - 1);
2326                 } else {
2327                         e->rdma_sge.mr = NULL;
2328                         e->rdma_sge.vaddr = NULL;
2329                         e->rdma_sge.length = 0;
2330                         e->rdma_sge.sge_length = 0;
2331                 }
2332                 e->opcode = opcode;
2333                 e->sent = 0;
2334                 e->psn = psn;
2335                 e->lpsn = qp->r_psn;
2336                 /*
2337                  * We need to increment the MSN here instead of when we
2338                  * finish sending the result since a duplicate request would
2339                  * increment it more than once.
2340                  */
2341                 qp->r_msn++;
2342                 qp->r_psn++;
2343                 qp->r_state = opcode;
2344                 qp->r_nak_state = 0;
2345                 qp->r_head_ack_queue = next;
2346
2347                 /* Schedule the send engine. */
2348                 qp->s_flags |= RVT_S_RESP_PENDING;
2349                 hfi1_schedule_send(qp);
2350
2351                 spin_unlock_irqrestore(&qp->s_lock, flags);
2352                 if (is_fecn)
2353                         goto send_ack;
2354                 return;
2355         }
2356
2357         case OP(COMPARE_SWAP):
2358         case OP(FETCH_ADD): {
2359                 struct ib_atomic_eth *ateth;
2360                 struct rvt_ack_entry *e;
2361                 u64 vaddr;
2362                 atomic64_t *maddr;
2363                 u64 sdata;
2364                 u32 rkey;
2365                 u8 next;
2366
2367                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
2368                         goto nack_inv;
2369                 next = qp->r_head_ack_queue + 1;
2370                 if (next > HFI1_MAX_RDMA_ATOMIC)
2371                         next = 0;
2372                 spin_lock_irqsave(&qp->s_lock, flags);
2373                 if (unlikely(next == qp->s_tail_ack_queue)) {
2374                         if (!qp->s_ack_queue[next].sent)
2375                                 goto nack_inv_unlck;
2376                         update_ack_queue(qp, next);
2377                 }
2378                 e = &qp->s_ack_queue[qp->r_head_ack_queue];
2379                 if (e->opcode == OP(RDMA_READ_REQUEST) && e->rdma_sge.mr) {
2380                         rvt_put_mr(e->rdma_sge.mr);
2381                         e->rdma_sge.mr = NULL;
2382                 }
2383                 ateth = &ohdr->u.atomic_eth;
2384                 vaddr = get_ib_ateth_vaddr(ateth);
2385                 if (unlikely(vaddr & (sizeof(u64) - 1)))
2386                         goto nack_inv_unlck;
2387                 rkey = be32_to_cpu(ateth->rkey);
2388                 /* Check rkey & NAK */
2389                 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
2390                                           vaddr, rkey,
2391                                           IB_ACCESS_REMOTE_ATOMIC)))
2392                         goto nack_acc_unlck;
2393                 /* Perform atomic OP and save result. */
2394                 maddr = (atomic64_t *)qp->r_sge.sge.vaddr;
2395                 sdata = get_ib_ateth_swap(ateth);
2396                 e->atomic_data = (opcode == OP(FETCH_ADD)) ?
2397                         (u64)atomic64_add_return(sdata, maddr) - sdata :
2398                         (u64)cmpxchg((u64 *)qp->r_sge.sge.vaddr,
2399                                       get_ib_ateth_compare(ateth),
2400                                       sdata);
2401                 rvt_put_mr(qp->r_sge.sge.mr);
2402                 qp->r_sge.num_sge = 0;
2403                 e->opcode = opcode;
2404                 e->sent = 0;
2405                 e->psn = psn;
2406                 e->lpsn = psn;
2407                 qp->r_msn++;
2408                 qp->r_psn++;
2409                 qp->r_state = opcode;
2410                 qp->r_nak_state = 0;
2411                 qp->r_head_ack_queue = next;
2412
2413                 /* Schedule the send engine. */
2414                 qp->s_flags |= RVT_S_RESP_PENDING;
2415                 hfi1_schedule_send(qp);
2416
2417                 spin_unlock_irqrestore(&qp->s_lock, flags);
2418                 if (is_fecn)
2419                         goto send_ack;
2420                 return;
2421         }
2422
2423         default:
2424                 /* NAK unknown opcodes. */
2425                 goto nack_inv;
2426         }
2427         qp->r_psn++;
2428         qp->r_state = opcode;
2429         qp->r_ack_psn = psn;
2430         qp->r_nak_state = 0;
2431         /* Send an ACK if requested or required. */
2432         if (psn & IB_BTH_REQ_ACK) {
2433                 if (packet->numpkt == 0) {
2434                         rc_cancel_ack(qp);
2435                         goto send_ack;
2436                 }
2437                 if (qp->r_adefered >= HFI1_PSN_CREDIT) {
2438                         rc_cancel_ack(qp);
2439                         goto send_ack;
2440                 }
2441                 if (unlikely(is_fecn)) {
2442                         rc_cancel_ack(qp);
2443                         goto send_ack;
2444                 }
2445                 qp->r_adefered++;
2446                 rc_defered_ack(rcd, qp);
2447         }
2448         return;
2449
2450 rnr_nak:
2451         qp->r_nak_state = qp->r_min_rnr_timer | IB_RNR_NAK;
2452         qp->r_ack_psn = qp->r_psn;
2453         /* Queue RNR NAK for later */
2454         rc_defered_ack(rcd, qp);
2455         return;
2456
2457 nack_op_err:
2458         rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
2459         qp->r_nak_state = IB_NAK_REMOTE_OPERATIONAL_ERROR;
2460         qp->r_ack_psn = qp->r_psn;
2461         /* Queue NAK for later */
2462         rc_defered_ack(rcd, qp);
2463         return;
2464
2465 nack_inv_unlck:
2466         spin_unlock_irqrestore(&qp->s_lock, flags);
2467 nack_inv:
2468         rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
2469         qp->r_nak_state = IB_NAK_INVALID_REQUEST;
2470         qp->r_ack_psn = qp->r_psn;
2471         /* Queue NAK for later */
2472         rc_defered_ack(rcd, qp);
2473         return;
2474
2475 nack_acc_unlck:
2476         spin_unlock_irqrestore(&qp->s_lock, flags);
2477 nack_acc:
2478         rvt_rc_error(qp, IB_WC_LOC_PROT_ERR);
2479         qp->r_nak_state = IB_NAK_REMOTE_ACCESS_ERROR;
2480         qp->r_ack_psn = qp->r_psn;
2481 send_ack:
2482         hfi1_send_rc_ack(rcd, qp, is_fecn);
2483 }
2484
2485 void hfi1_rc_hdrerr(
2486         struct hfi1_ctxtdata *rcd,
2487         struct hfi1_packet *packet,
2488         struct rvt_qp *qp)
2489 {
2490         struct hfi1_ibport *ibp = rcd_to_iport(rcd);
2491         int diff;
2492         u32 opcode;
2493         u32 psn;
2494
2495         if (hfi1_ruc_check_hdr(ibp, packet))
2496                 return;
2497
2498         psn = ib_bth_get_psn(packet->ohdr);
2499         opcode = ib_bth_get_opcode(packet->ohdr);
2500
2501         /* Only deal with RDMA Writes for now */
2502         if (opcode < IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) {
2503                 diff = delta_psn(psn, qp->r_psn);
2504                 if (!qp->r_nak_state && diff >= 0) {
2505                         ibp->rvp.n_rc_seqnak++;
2506                         qp->r_nak_state = IB_NAK_PSN_ERROR;
2507                         /* Use the expected PSN. */
2508                         qp->r_ack_psn = qp->r_psn;
2509                         /*
2510                          * Wait to send the sequence
2511                          * NAK until all packets
2512                          * in the receive queue have
2513                          * been processed.
2514                          * Otherwise, we end up
2515                          * propagating congestion.
2516                          */
2517                         rc_defered_ack(rcd, qp);
2518                 } /* Out of sequence NAK */
2519         } /* QP Request NAKs */
2520 }