GNU Linux-libre 4.19.268-gnu1
[releases.git] / drivers / infiniband / sw / rxe / rxe_resp.c
1 /*
2  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
3  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33
34 #include <linux/skbuff.h>
35
36 #include "rxe.h"
37 #include "rxe_loc.h"
38 #include "rxe_queue.h"
39
40 enum resp_states {
41         RESPST_NONE,
42         RESPST_GET_REQ,
43         RESPST_CHK_PSN,
44         RESPST_CHK_OP_SEQ,
45         RESPST_CHK_OP_VALID,
46         RESPST_CHK_RESOURCE,
47         RESPST_CHK_LENGTH,
48         RESPST_CHK_RKEY,
49         RESPST_EXECUTE,
50         RESPST_READ_REPLY,
51         RESPST_COMPLETE,
52         RESPST_ACKNOWLEDGE,
53         RESPST_CLEANUP,
54         RESPST_DUPLICATE_REQUEST,
55         RESPST_ERR_MALFORMED_WQE,
56         RESPST_ERR_UNSUPPORTED_OPCODE,
57         RESPST_ERR_MISALIGNED_ATOMIC,
58         RESPST_ERR_PSN_OUT_OF_SEQ,
59         RESPST_ERR_MISSING_OPCODE_FIRST,
60         RESPST_ERR_MISSING_OPCODE_LAST_C,
61         RESPST_ERR_MISSING_OPCODE_LAST_D1E,
62         RESPST_ERR_TOO_MANY_RDMA_ATM_REQ,
63         RESPST_ERR_RNR,
64         RESPST_ERR_RKEY_VIOLATION,
65         RESPST_ERR_LENGTH,
66         RESPST_ERR_CQ_OVERFLOW,
67         RESPST_ERROR,
68         RESPST_RESET,
69         RESPST_DONE,
70         RESPST_EXIT,
71 };
72
73 static char *resp_state_name[] = {
74         [RESPST_NONE]                           = "NONE",
75         [RESPST_GET_REQ]                        = "GET_REQ",
76         [RESPST_CHK_PSN]                        = "CHK_PSN",
77         [RESPST_CHK_OP_SEQ]                     = "CHK_OP_SEQ",
78         [RESPST_CHK_OP_VALID]                   = "CHK_OP_VALID",
79         [RESPST_CHK_RESOURCE]                   = "CHK_RESOURCE",
80         [RESPST_CHK_LENGTH]                     = "CHK_LENGTH",
81         [RESPST_CHK_RKEY]                       = "CHK_RKEY",
82         [RESPST_EXECUTE]                        = "EXECUTE",
83         [RESPST_READ_REPLY]                     = "READ_REPLY",
84         [RESPST_COMPLETE]                       = "COMPLETE",
85         [RESPST_ACKNOWLEDGE]                    = "ACKNOWLEDGE",
86         [RESPST_CLEANUP]                        = "CLEANUP",
87         [RESPST_DUPLICATE_REQUEST]              = "DUPLICATE_REQUEST",
88         [RESPST_ERR_MALFORMED_WQE]              = "ERR_MALFORMED_WQE",
89         [RESPST_ERR_UNSUPPORTED_OPCODE]         = "ERR_UNSUPPORTED_OPCODE",
90         [RESPST_ERR_MISALIGNED_ATOMIC]          = "ERR_MISALIGNED_ATOMIC",
91         [RESPST_ERR_PSN_OUT_OF_SEQ]             = "ERR_PSN_OUT_OF_SEQ",
92         [RESPST_ERR_MISSING_OPCODE_FIRST]       = "ERR_MISSING_OPCODE_FIRST",
93         [RESPST_ERR_MISSING_OPCODE_LAST_C]      = "ERR_MISSING_OPCODE_LAST_C",
94         [RESPST_ERR_MISSING_OPCODE_LAST_D1E]    = "ERR_MISSING_OPCODE_LAST_D1E",
95         [RESPST_ERR_TOO_MANY_RDMA_ATM_REQ]      = "ERR_TOO_MANY_RDMA_ATM_REQ",
96         [RESPST_ERR_RNR]                        = "ERR_RNR",
97         [RESPST_ERR_RKEY_VIOLATION]             = "ERR_RKEY_VIOLATION",
98         [RESPST_ERR_LENGTH]                     = "ERR_LENGTH",
99         [RESPST_ERR_CQ_OVERFLOW]                = "ERR_CQ_OVERFLOW",
100         [RESPST_ERROR]                          = "ERROR",
101         [RESPST_RESET]                          = "RESET",
102         [RESPST_DONE]                           = "DONE",
103         [RESPST_EXIT]                           = "EXIT",
104 };
105
106 /* rxe_recv calls here to add a request packet to the input queue */
107 void rxe_resp_queue_pkt(struct rxe_dev *rxe, struct rxe_qp *qp,
108                         struct sk_buff *skb)
109 {
110         int must_sched;
111         struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
112
113         skb_queue_tail(&qp->req_pkts, skb);
114
115         must_sched = (pkt->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST) ||
116                         (skb_queue_len(&qp->req_pkts) > 1);
117
118         rxe_run_task(&qp->resp.task, must_sched);
119 }
120
121 static inline enum resp_states get_req(struct rxe_qp *qp,
122                                        struct rxe_pkt_info **pkt_p)
123 {
124         struct sk_buff *skb;
125
126         if (qp->resp.state == QP_STATE_ERROR) {
127                 skb = skb_dequeue(&qp->req_pkts);
128                 if (skb) {
129                         /* drain request packet queue */
130                         rxe_drop_ref(qp);
131                         kfree_skb(skb);
132                         return RESPST_GET_REQ;
133                 }
134
135                 /* go drain recv wr queue */
136                 return RESPST_CHK_RESOURCE;
137         }
138
139         skb = skb_peek(&qp->req_pkts);
140         if (!skb)
141                 return RESPST_EXIT;
142
143         *pkt_p = SKB_TO_PKT(skb);
144
145         return (qp->resp.res) ? RESPST_READ_REPLY : RESPST_CHK_PSN;
146 }
147
148 static enum resp_states check_psn(struct rxe_qp *qp,
149                                   struct rxe_pkt_info *pkt)
150 {
151         int diff = psn_compare(pkt->psn, qp->resp.psn);
152         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
153
154         switch (qp_type(qp)) {
155         case IB_QPT_RC:
156                 if (diff > 0) {
157                         if (qp->resp.sent_psn_nak)
158                                 return RESPST_CLEANUP;
159
160                         qp->resp.sent_psn_nak = 1;
161                         rxe_counter_inc(rxe, RXE_CNT_OUT_OF_SEQ_REQ);
162                         return RESPST_ERR_PSN_OUT_OF_SEQ;
163
164                 } else if (diff < 0) {
165                         rxe_counter_inc(rxe, RXE_CNT_DUP_REQ);
166                         return RESPST_DUPLICATE_REQUEST;
167                 }
168
169                 if (qp->resp.sent_psn_nak)
170                         qp->resp.sent_psn_nak = 0;
171
172                 break;
173
174         case IB_QPT_UC:
175                 if (qp->resp.drop_msg || diff != 0) {
176                         if (pkt->mask & RXE_START_MASK) {
177                                 qp->resp.drop_msg = 0;
178                                 return RESPST_CHK_OP_SEQ;
179                         }
180
181                         qp->resp.drop_msg = 1;
182                         return RESPST_CLEANUP;
183                 }
184                 break;
185         default:
186                 break;
187         }
188
189         return RESPST_CHK_OP_SEQ;
190 }
191
192 static enum resp_states check_op_seq(struct rxe_qp *qp,
193                                      struct rxe_pkt_info *pkt)
194 {
195         switch (qp_type(qp)) {
196         case IB_QPT_RC:
197                 switch (qp->resp.opcode) {
198                 case IB_OPCODE_RC_SEND_FIRST:
199                 case IB_OPCODE_RC_SEND_MIDDLE:
200                         switch (pkt->opcode) {
201                         case IB_OPCODE_RC_SEND_MIDDLE:
202                         case IB_OPCODE_RC_SEND_LAST:
203                         case IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE:
204                         case IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE:
205                                 return RESPST_CHK_OP_VALID;
206                         default:
207                                 return RESPST_ERR_MISSING_OPCODE_LAST_C;
208                         }
209
210                 case IB_OPCODE_RC_RDMA_WRITE_FIRST:
211                 case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
212                         switch (pkt->opcode) {
213                         case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
214                         case IB_OPCODE_RC_RDMA_WRITE_LAST:
215                         case IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
216                                 return RESPST_CHK_OP_VALID;
217                         default:
218                                 return RESPST_ERR_MISSING_OPCODE_LAST_C;
219                         }
220
221                 default:
222                         switch (pkt->opcode) {
223                         case IB_OPCODE_RC_SEND_MIDDLE:
224                         case IB_OPCODE_RC_SEND_LAST:
225                         case IB_OPCODE_RC_SEND_LAST_WITH_IMMEDIATE:
226                         case IB_OPCODE_RC_SEND_LAST_WITH_INVALIDATE:
227                         case IB_OPCODE_RC_RDMA_WRITE_MIDDLE:
228                         case IB_OPCODE_RC_RDMA_WRITE_LAST:
229                         case IB_OPCODE_RC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
230                                 return RESPST_ERR_MISSING_OPCODE_FIRST;
231                         default:
232                                 return RESPST_CHK_OP_VALID;
233                         }
234                 }
235                 break;
236
237         case IB_QPT_UC:
238                 switch (qp->resp.opcode) {
239                 case IB_OPCODE_UC_SEND_FIRST:
240                 case IB_OPCODE_UC_SEND_MIDDLE:
241                         switch (pkt->opcode) {
242                         case IB_OPCODE_UC_SEND_MIDDLE:
243                         case IB_OPCODE_UC_SEND_LAST:
244                         case IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE:
245                                 return RESPST_CHK_OP_VALID;
246                         default:
247                                 return RESPST_ERR_MISSING_OPCODE_LAST_D1E;
248                         }
249
250                 case IB_OPCODE_UC_RDMA_WRITE_FIRST:
251                 case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
252                         switch (pkt->opcode) {
253                         case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
254                         case IB_OPCODE_UC_RDMA_WRITE_LAST:
255                         case IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
256                                 return RESPST_CHK_OP_VALID;
257                         default:
258                                 return RESPST_ERR_MISSING_OPCODE_LAST_D1E;
259                         }
260
261                 default:
262                         switch (pkt->opcode) {
263                         case IB_OPCODE_UC_SEND_MIDDLE:
264                         case IB_OPCODE_UC_SEND_LAST:
265                         case IB_OPCODE_UC_SEND_LAST_WITH_IMMEDIATE:
266                         case IB_OPCODE_UC_RDMA_WRITE_MIDDLE:
267                         case IB_OPCODE_UC_RDMA_WRITE_LAST:
268                         case IB_OPCODE_UC_RDMA_WRITE_LAST_WITH_IMMEDIATE:
269                                 qp->resp.drop_msg = 1;
270                                 return RESPST_CLEANUP;
271                         default:
272                                 return RESPST_CHK_OP_VALID;
273                         }
274                 }
275                 break;
276
277         default:
278                 return RESPST_CHK_OP_VALID;
279         }
280 }
281
282 static enum resp_states check_op_valid(struct rxe_qp *qp,
283                                        struct rxe_pkt_info *pkt)
284 {
285         switch (qp_type(qp)) {
286         case IB_QPT_RC:
287                 if (((pkt->mask & RXE_READ_MASK) &&
288                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_READ)) ||
289                     ((pkt->mask & RXE_WRITE_MASK) &&
290                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_WRITE)) ||
291                     ((pkt->mask & RXE_ATOMIC_MASK) &&
292                      !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_ATOMIC))) {
293                         return RESPST_ERR_UNSUPPORTED_OPCODE;
294                 }
295
296                 break;
297
298         case IB_QPT_UC:
299                 if ((pkt->mask & RXE_WRITE_MASK) &&
300                     !(qp->attr.qp_access_flags & IB_ACCESS_REMOTE_WRITE)) {
301                         qp->resp.drop_msg = 1;
302                         return RESPST_CLEANUP;
303                 }
304
305                 break;
306
307         case IB_QPT_UD:
308         case IB_QPT_SMI:
309         case IB_QPT_GSI:
310                 break;
311
312         default:
313                 WARN_ON_ONCE(1);
314                 break;
315         }
316
317         return RESPST_CHK_RESOURCE;
318 }
319
320 static enum resp_states get_srq_wqe(struct rxe_qp *qp)
321 {
322         struct rxe_srq *srq = qp->srq;
323         struct rxe_queue *q = srq->rq.queue;
324         struct rxe_recv_wqe *wqe;
325         struct ib_event ev;
326
327         if (srq->error)
328                 return RESPST_ERR_RNR;
329
330         spin_lock_bh(&srq->rq.consumer_lock);
331
332         wqe = queue_head(q);
333         if (!wqe) {
334                 spin_unlock_bh(&srq->rq.consumer_lock);
335                 return RESPST_ERR_RNR;
336         }
337
338         /* note kernel and user space recv wqes have same size */
339         memcpy(&qp->resp.srq_wqe, wqe, sizeof(qp->resp.srq_wqe));
340
341         qp->resp.wqe = &qp->resp.srq_wqe.wqe;
342         advance_consumer(q);
343
344         if (srq->limit && srq->ibsrq.event_handler &&
345             (queue_count(q) < srq->limit)) {
346                 srq->limit = 0;
347                 goto event;
348         }
349
350         spin_unlock_bh(&srq->rq.consumer_lock);
351         return RESPST_CHK_LENGTH;
352
353 event:
354         spin_unlock_bh(&srq->rq.consumer_lock);
355         ev.device = qp->ibqp.device;
356         ev.element.srq = qp->ibqp.srq;
357         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
358         srq->ibsrq.event_handler(&ev, srq->ibsrq.srq_context);
359         return RESPST_CHK_LENGTH;
360 }
361
362 static enum resp_states check_resource(struct rxe_qp *qp,
363                                        struct rxe_pkt_info *pkt)
364 {
365         struct rxe_srq *srq = qp->srq;
366
367         if (qp->resp.state == QP_STATE_ERROR) {
368                 if (qp->resp.wqe) {
369                         qp->resp.status = IB_WC_WR_FLUSH_ERR;
370                         return RESPST_COMPLETE;
371                 } else if (!srq) {
372                         qp->resp.wqe = queue_head(qp->rq.queue);
373                         if (qp->resp.wqe) {
374                                 qp->resp.status = IB_WC_WR_FLUSH_ERR;
375                                 return RESPST_COMPLETE;
376                         } else {
377                                 return RESPST_EXIT;
378                         }
379                 } else {
380                         return RESPST_EXIT;
381                 }
382         }
383
384         if (pkt->mask & RXE_READ_OR_ATOMIC) {
385                 /* it is the requesters job to not send
386                  * too many read/atomic ops, we just
387                  * recycle the responder resource queue
388                  */
389                 if (likely(qp->attr.max_dest_rd_atomic > 0))
390                         return RESPST_CHK_LENGTH;
391                 else
392                         return RESPST_ERR_TOO_MANY_RDMA_ATM_REQ;
393         }
394
395         if (pkt->mask & RXE_RWR_MASK) {
396                 if (srq)
397                         return get_srq_wqe(qp);
398
399                 qp->resp.wqe = queue_head(qp->rq.queue);
400                 return (qp->resp.wqe) ? RESPST_CHK_LENGTH : RESPST_ERR_RNR;
401         }
402
403         return RESPST_CHK_LENGTH;
404 }
405
406 static enum resp_states check_length(struct rxe_qp *qp,
407                                      struct rxe_pkt_info *pkt)
408 {
409         switch (qp_type(qp)) {
410         case IB_QPT_RC:
411                 return RESPST_CHK_RKEY;
412
413         case IB_QPT_UC:
414                 return RESPST_CHK_RKEY;
415
416         default:
417                 return RESPST_CHK_RKEY;
418         }
419 }
420
421 static enum resp_states check_rkey(struct rxe_qp *qp,
422                                    struct rxe_pkt_info *pkt)
423 {
424         struct rxe_mem *mem = NULL;
425         u64 va;
426         u32 rkey;
427         u32 resid;
428         u32 pktlen;
429         int mtu = qp->mtu;
430         enum resp_states state;
431         int access;
432
433         if (pkt->mask & (RXE_READ_MASK | RXE_WRITE_MASK)) {
434                 if (pkt->mask & RXE_RETH_MASK) {
435                         qp->resp.va = reth_va(pkt);
436                         qp->resp.rkey = reth_rkey(pkt);
437                         qp->resp.resid = reth_len(pkt);
438                         qp->resp.length = reth_len(pkt);
439                 }
440                 access = (pkt->mask & RXE_READ_MASK) ? IB_ACCESS_REMOTE_READ
441                                                      : IB_ACCESS_REMOTE_WRITE;
442         } else if (pkt->mask & RXE_ATOMIC_MASK) {
443                 qp->resp.va = atmeth_va(pkt);
444                 qp->resp.rkey = atmeth_rkey(pkt);
445                 qp->resp.resid = sizeof(u64);
446                 access = IB_ACCESS_REMOTE_ATOMIC;
447         } else {
448                 return RESPST_EXECUTE;
449         }
450
451         /* A zero-byte op is not required to set an addr or rkey. */
452         if ((pkt->mask & (RXE_READ_MASK | RXE_WRITE_OR_SEND)) &&
453             (pkt->mask & RXE_RETH_MASK) &&
454             reth_len(pkt) == 0) {
455                 return RESPST_EXECUTE;
456         }
457
458         va      = qp->resp.va;
459         rkey    = qp->resp.rkey;
460         resid   = qp->resp.resid;
461         pktlen  = payload_size(pkt);
462
463         mem = lookup_mem(qp->pd, access, rkey, lookup_remote);
464         if (!mem) {
465                 state = RESPST_ERR_RKEY_VIOLATION;
466                 goto err;
467         }
468
469         if (unlikely(mem->state == RXE_MEM_STATE_FREE)) {
470                 state = RESPST_ERR_RKEY_VIOLATION;
471                 goto err;
472         }
473
474         if (mem_check_range(mem, va, resid)) {
475                 state = RESPST_ERR_RKEY_VIOLATION;
476                 goto err;
477         }
478
479         if (pkt->mask & RXE_WRITE_MASK)  {
480                 if (resid > mtu) {
481                         if (pktlen != mtu || bth_pad(pkt)) {
482                                 state = RESPST_ERR_LENGTH;
483                                 goto err;
484                         }
485                 } else {
486                         if (pktlen != resid) {
487                                 state = RESPST_ERR_LENGTH;
488                                 goto err;
489                         }
490                         if ((bth_pad(pkt) != (0x3 & (-resid)))) {
491                                 /* This case may not be exactly that
492                                  * but nothing else fits.
493                                  */
494                                 state = RESPST_ERR_LENGTH;
495                                 goto err;
496                         }
497                 }
498         }
499
500         WARN_ON_ONCE(qp->resp.mr);
501
502         qp->resp.mr = mem;
503         return RESPST_EXECUTE;
504
505 err:
506         if (mem)
507                 rxe_drop_ref(mem);
508         return state;
509 }
510
511 static enum resp_states send_data_in(struct rxe_qp *qp, void *data_addr,
512                                      int data_len)
513 {
514         int err;
515
516         err = copy_data(qp->pd, IB_ACCESS_LOCAL_WRITE, &qp->resp.wqe->dma,
517                         data_addr, data_len, to_mem_obj, NULL);
518         if (unlikely(err))
519                 return (err == -ENOSPC) ? RESPST_ERR_LENGTH
520                                         : RESPST_ERR_MALFORMED_WQE;
521
522         return RESPST_NONE;
523 }
524
525 static enum resp_states write_data_in(struct rxe_qp *qp,
526                                       struct rxe_pkt_info *pkt)
527 {
528         enum resp_states rc = RESPST_NONE;
529         int     err;
530         int data_len = payload_size(pkt);
531
532         err = rxe_mem_copy(qp->resp.mr, qp->resp.va, payload_addr(pkt),
533                            data_len, to_mem_obj, NULL);
534         if (err) {
535                 rc = RESPST_ERR_RKEY_VIOLATION;
536                 goto out;
537         }
538
539         qp->resp.va += data_len;
540         qp->resp.resid -= data_len;
541
542 out:
543         return rc;
544 }
545
546 /* Guarantee atomicity of atomic operations at the machine level. */
547 static DEFINE_SPINLOCK(atomic_ops_lock);
548
549 static enum resp_states process_atomic(struct rxe_qp *qp,
550                                        struct rxe_pkt_info *pkt)
551 {
552         u64 iova = atmeth_va(pkt);
553         u64 *vaddr;
554         enum resp_states ret;
555         struct rxe_mem *mr = qp->resp.mr;
556
557         if (mr->state != RXE_MEM_STATE_VALID) {
558                 ret = RESPST_ERR_RKEY_VIOLATION;
559                 goto out;
560         }
561
562         vaddr = iova_to_vaddr(mr, iova, sizeof(u64));
563
564         /* check vaddr is 8 bytes aligned. */
565         if (!vaddr || (uintptr_t)vaddr & 7) {
566                 ret = RESPST_ERR_MISALIGNED_ATOMIC;
567                 goto out;
568         }
569
570         spin_lock_bh(&atomic_ops_lock);
571
572         qp->resp.atomic_orig = *vaddr;
573
574         if (pkt->opcode == IB_OPCODE_RC_COMPARE_SWAP ||
575             pkt->opcode == IB_OPCODE_RD_COMPARE_SWAP) {
576                 if (*vaddr == atmeth_comp(pkt))
577                         *vaddr = atmeth_swap_add(pkt);
578         } else {
579                 *vaddr += atmeth_swap_add(pkt);
580         }
581
582         spin_unlock_bh(&atomic_ops_lock);
583
584         ret = RESPST_NONE;
585 out:
586         return ret;
587 }
588
589 static struct sk_buff *prepare_ack_packet(struct rxe_qp *qp,
590                                           struct rxe_pkt_info *pkt,
591                                           struct rxe_pkt_info *ack,
592                                           int opcode,
593                                           int payload,
594                                           u32 psn,
595                                           u8 syndrome,
596                                           u32 *crcp)
597 {
598         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
599         struct sk_buff *skb;
600         u32 crc = 0;
601         u32 *p;
602         int paylen;
603         int pad;
604         int err;
605
606         /*
607          * allocate packet
608          */
609         pad = (-payload) & 0x3;
610         paylen = rxe_opcode[opcode].length + payload + pad + RXE_ICRC_SIZE;
611
612         skb = rxe_init_packet(rxe, &qp->pri_av, paylen, ack);
613         if (!skb)
614                 return NULL;
615
616         ack->qp = qp;
617         ack->opcode = opcode;
618         ack->mask = rxe_opcode[opcode].mask;
619         ack->offset = pkt->offset;
620         ack->paylen = paylen;
621
622         /* fill in bth using the request packet headers */
623         memcpy(ack->hdr, pkt->hdr, pkt->offset + RXE_BTH_BYTES);
624
625         bth_set_opcode(ack, opcode);
626         bth_set_qpn(ack, qp->attr.dest_qp_num);
627         bth_set_pad(ack, pad);
628         bth_set_se(ack, 0);
629         bth_set_psn(ack, psn);
630         bth_set_ack(ack, 0);
631         ack->psn = psn;
632
633         if (ack->mask & RXE_AETH_MASK) {
634                 aeth_set_syn(ack, syndrome);
635                 aeth_set_msn(ack, qp->resp.msn);
636         }
637
638         if (ack->mask & RXE_ATMACK_MASK)
639                 atmack_set_orig(ack, qp->resp.atomic_orig);
640
641         err = rxe_prepare(rxe, ack, skb, &crc);
642         if (err) {
643                 kfree_skb(skb);
644                 return NULL;
645         }
646
647         if (crcp) {
648                 /* CRC computation will be continued by the caller */
649                 *crcp = crc;
650         } else {
651                 p = payload_addr(ack) + payload + bth_pad(ack);
652                 *p = ~crc;
653         }
654
655         return skb;
656 }
657
658 /* RDMA read response. If res is not NULL, then we have a current RDMA request
659  * being processed or replayed.
660  */
661 static enum resp_states read_reply(struct rxe_qp *qp,
662                                    struct rxe_pkt_info *req_pkt)
663 {
664         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
665         struct rxe_pkt_info ack_pkt;
666         struct sk_buff *skb;
667         int mtu = qp->mtu;
668         enum resp_states state;
669         int payload;
670         int opcode;
671         int err;
672         struct resp_res *res = qp->resp.res;
673         u32 icrc;
674         u32 *p;
675
676         if (!res) {
677                 /* This is the first time we process that request. Get a
678                  * resource
679                  */
680                 res = &qp->resp.resources[qp->resp.res_head];
681
682                 free_rd_atomic_resource(qp, res);
683                 rxe_advance_resp_resource(qp);
684
685                 res->type               = RXE_READ_MASK;
686                 res->replay             = 0;
687
688                 res->read.va            = qp->resp.va;
689                 res->read.va_org        = qp->resp.va;
690
691                 res->first_psn          = req_pkt->psn;
692
693                 if (reth_len(req_pkt)) {
694                         res->last_psn   = (req_pkt->psn +
695                                            (reth_len(req_pkt) + mtu - 1) /
696                                            mtu - 1) & BTH_PSN_MASK;
697                 } else {
698                         res->last_psn   = res->first_psn;
699                 }
700                 res->cur_psn            = req_pkt->psn;
701
702                 res->read.resid         = qp->resp.resid;
703                 res->read.length        = qp->resp.resid;
704                 res->read.rkey          = qp->resp.rkey;
705
706                 /* note res inherits the reference to mr from qp */
707                 res->read.mr            = qp->resp.mr;
708                 qp->resp.mr             = NULL;
709
710                 qp->resp.res            = res;
711                 res->state              = rdatm_res_state_new;
712         }
713
714         if (res->state == rdatm_res_state_new) {
715                 if (res->read.resid <= mtu)
716                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY;
717                 else
718                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST;
719         } else {
720                 if (res->read.resid > mtu)
721                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE;
722                 else
723                         opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST;
724         }
725
726         res->state = rdatm_res_state_next;
727
728         payload = min_t(int, res->read.resid, mtu);
729
730         skb = prepare_ack_packet(qp, req_pkt, &ack_pkt, opcode, payload,
731                                  res->cur_psn, AETH_ACK_UNLIMITED, &icrc);
732         if (!skb)
733                 return RESPST_ERR_RNR;
734
735         err = rxe_mem_copy(res->read.mr, res->read.va, payload_addr(&ack_pkt),
736                            payload, from_mem_obj, &icrc);
737         if (err)
738                 pr_err("Failed copying memory\n");
739
740         if (bth_pad(&ack_pkt)) {
741                 struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
742                 u8 *pad = payload_addr(&ack_pkt) + payload;
743
744                 memset(pad, 0, bth_pad(&ack_pkt));
745                 icrc = rxe_crc32(rxe, icrc, pad, bth_pad(&ack_pkt));
746         }
747         p = payload_addr(&ack_pkt) + payload + bth_pad(&ack_pkt);
748         *p = ~icrc;
749
750         err = rxe_xmit_packet(rxe, qp, &ack_pkt, skb);
751         if (err) {
752                 pr_err("Failed sending RDMA reply.\n");
753                 return RESPST_ERR_RNR;
754         }
755
756         res->read.va += payload;
757         res->read.resid -= payload;
758         res->cur_psn = (res->cur_psn + 1) & BTH_PSN_MASK;
759
760         if (res->read.resid > 0) {
761                 state = RESPST_DONE;
762         } else {
763                 qp->resp.res = NULL;
764                 if (!res->replay)
765                         qp->resp.opcode = -1;
766                 if (psn_compare(res->cur_psn, qp->resp.psn) >= 0)
767                         qp->resp.psn = res->cur_psn;
768                 state = RESPST_CLEANUP;
769         }
770
771         return state;
772 }
773
774 static void build_rdma_network_hdr(union rdma_network_hdr *hdr,
775                                    struct rxe_pkt_info *pkt)
776 {
777         struct sk_buff *skb = PKT_TO_SKB(pkt);
778
779         memset(hdr, 0, sizeof(*hdr));
780         if (skb->protocol == htons(ETH_P_IP))
781                 memcpy(&hdr->roce4grh, ip_hdr(skb), sizeof(hdr->roce4grh));
782         else if (skb->protocol == htons(ETH_P_IPV6))
783                 memcpy(&hdr->ibgrh, ipv6_hdr(skb), sizeof(hdr->ibgrh));
784 }
785
786 /* Executes a new request. A retried request never reach that function (send
787  * and writes are discarded, and reads and atomics are retried elsewhere.
788  */
789 static enum resp_states execute(struct rxe_qp *qp, struct rxe_pkt_info *pkt)
790 {
791         enum resp_states err;
792
793         if (pkt->mask & RXE_SEND_MASK) {
794                 if (qp_type(qp) == IB_QPT_UD ||
795                     qp_type(qp) == IB_QPT_SMI ||
796                     qp_type(qp) == IB_QPT_GSI) {
797                         union rdma_network_hdr hdr;
798
799                         build_rdma_network_hdr(&hdr, pkt);
800
801                         err = send_data_in(qp, &hdr, sizeof(hdr));
802                         if (err)
803                                 return err;
804                 }
805                 err = send_data_in(qp, payload_addr(pkt), payload_size(pkt));
806                 if (err)
807                         return err;
808         } else if (pkt->mask & RXE_WRITE_MASK) {
809                 err = write_data_in(qp, pkt);
810                 if (err)
811                         return err;
812         } else if (pkt->mask & RXE_READ_MASK) {
813                 /* For RDMA Read we can increment the msn now. See C9-148. */
814                 qp->resp.msn++;
815                 return RESPST_READ_REPLY;
816         } else if (pkt->mask & RXE_ATOMIC_MASK) {
817                 err = process_atomic(qp, pkt);
818                 if (err)
819                         return err;
820         } else {
821                 /* Unreachable */
822                 WARN_ON_ONCE(1);
823         }
824
825         /* next expected psn, read handles this separately */
826         qp->resp.psn = (pkt->psn + 1) & BTH_PSN_MASK;
827         qp->resp.ack_psn = qp->resp.psn;
828
829         qp->resp.opcode = pkt->opcode;
830         qp->resp.status = IB_WC_SUCCESS;
831
832         if (pkt->mask & RXE_COMP_MASK) {
833                 /* We successfully processed this new request. */
834                 qp->resp.msn++;
835                 return RESPST_COMPLETE;
836         } else if (qp_type(qp) == IB_QPT_RC)
837                 return RESPST_ACKNOWLEDGE;
838         else
839                 return RESPST_CLEANUP;
840 }
841
842 static enum resp_states do_complete(struct rxe_qp *qp,
843                                     struct rxe_pkt_info *pkt)
844 {
845         struct rxe_cqe cqe;
846         struct ib_wc *wc = &cqe.ibwc;
847         struct ib_uverbs_wc *uwc = &cqe.uibwc;
848         struct rxe_recv_wqe *wqe = qp->resp.wqe;
849
850         if (unlikely(!wqe))
851                 return RESPST_CLEANUP;
852
853         memset(&cqe, 0, sizeof(cqe));
854
855         if (qp->rcq->is_user) {
856                 uwc->status             = qp->resp.status;
857                 uwc->qp_num             = qp->ibqp.qp_num;
858                 uwc->wr_id              = wqe->wr_id;
859         } else {
860                 wc->status              = qp->resp.status;
861                 wc->qp                  = &qp->ibqp;
862                 wc->wr_id               = wqe->wr_id;
863         }
864
865         if (wc->status == IB_WC_SUCCESS) {
866                 wc->opcode = (pkt->mask & RXE_IMMDT_MASK &&
867                                 pkt->mask & RXE_WRITE_MASK) ?
868                                         IB_WC_RECV_RDMA_WITH_IMM : IB_WC_RECV;
869                 wc->vendor_err = 0;
870                 wc->byte_len = (pkt->mask & RXE_IMMDT_MASK &&
871                                 pkt->mask & RXE_WRITE_MASK) ?
872                                         qp->resp.length : wqe->dma.length - wqe->dma.resid;
873
874                 /* fields after byte_len are different between kernel and user
875                  * space
876                  */
877                 if (qp->rcq->is_user) {
878                         uwc->wc_flags = IB_WC_GRH;
879
880                         if (pkt->mask & RXE_IMMDT_MASK) {
881                                 uwc->wc_flags |= IB_WC_WITH_IMM;
882                                 uwc->ex.imm_data = immdt_imm(pkt);
883                         }
884
885                         if (pkt->mask & RXE_IETH_MASK) {
886                                 uwc->wc_flags |= IB_WC_WITH_INVALIDATE;
887                                 uwc->ex.invalidate_rkey = ieth_rkey(pkt);
888                         }
889
890                         uwc->qp_num             = qp->ibqp.qp_num;
891
892                         if (pkt->mask & RXE_DETH_MASK)
893                                 uwc->src_qp = deth_sqp(pkt);
894
895                         uwc->port_num           = qp->attr.port_num;
896                 } else {
897                         struct sk_buff *skb = PKT_TO_SKB(pkt);
898
899                         wc->wc_flags = IB_WC_GRH | IB_WC_WITH_NETWORK_HDR_TYPE;
900                         if (skb->protocol == htons(ETH_P_IP))
901                                 wc->network_hdr_type = RDMA_NETWORK_IPV4;
902                         else
903                                 wc->network_hdr_type = RDMA_NETWORK_IPV6;
904
905                         if (is_vlan_dev(skb->dev)) {
906                                 wc->wc_flags |= IB_WC_WITH_VLAN;
907                                 wc->vlan_id = vlan_dev_vlan_id(skb->dev);
908                         }
909
910                         if (pkt->mask & RXE_IMMDT_MASK) {
911                                 wc->wc_flags |= IB_WC_WITH_IMM;
912                                 wc->ex.imm_data = immdt_imm(pkt);
913                         }
914
915                         if (pkt->mask & RXE_IETH_MASK) {
916                                 struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
917                                 struct rxe_mem *rmr;
918
919                                 wc->wc_flags |= IB_WC_WITH_INVALIDATE;
920                                 wc->ex.invalidate_rkey = ieth_rkey(pkt);
921
922                                 rmr = rxe_pool_get_index(&rxe->mr_pool,
923                                                          wc->ex.invalidate_rkey >> 8);
924                                 if (unlikely(!rmr)) {
925                                         pr_err("Bad rkey %#x invalidation\n",
926                                                wc->ex.invalidate_rkey);
927                                         return RESPST_ERROR;
928                                 }
929                                 rmr->state = RXE_MEM_STATE_FREE;
930                                 rxe_drop_ref(rmr);
931                         }
932
933                         wc->qp                  = &qp->ibqp;
934
935                         if (pkt->mask & RXE_DETH_MASK)
936                                 wc->src_qp = deth_sqp(pkt);
937
938                         wc->port_num            = qp->attr.port_num;
939                 }
940         }
941
942         /* have copy for srq and reference for !srq */
943         if (!qp->srq)
944                 advance_consumer(qp->rq.queue);
945
946         qp->resp.wqe = NULL;
947
948         if (rxe_cq_post(qp->rcq, &cqe, pkt ? bth_se(pkt) : 1))
949                 return RESPST_ERR_CQ_OVERFLOW;
950
951         if (qp->resp.state == QP_STATE_ERROR)
952                 return RESPST_CHK_RESOURCE;
953
954         if (!pkt)
955                 return RESPST_DONE;
956         else if (qp_type(qp) == IB_QPT_RC)
957                 return RESPST_ACKNOWLEDGE;
958         else
959                 return RESPST_CLEANUP;
960 }
961
962 static int send_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
963                     u8 syndrome, u32 psn)
964 {
965         int err = 0;
966         struct rxe_pkt_info ack_pkt;
967         struct sk_buff *skb;
968         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
969
970         skb = prepare_ack_packet(qp, pkt, &ack_pkt, IB_OPCODE_RC_ACKNOWLEDGE,
971                                  0, psn, syndrome, NULL);
972         if (!skb) {
973                 err = -ENOMEM;
974                 goto err1;
975         }
976
977         err = rxe_xmit_packet(rxe, qp, &ack_pkt, skb);
978         if (err)
979                 pr_err_ratelimited("Failed sending ack\n");
980
981 err1:
982         return err;
983 }
984
985 static int send_atomic_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt,
986                            u8 syndrome)
987 {
988         int rc = 0;
989         struct rxe_pkt_info ack_pkt;
990         struct sk_buff *skb;
991         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
992         struct resp_res *res;
993
994         skb = prepare_ack_packet(qp, pkt, &ack_pkt,
995                                  IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE, 0, pkt->psn,
996                                  syndrome, NULL);
997         if (!skb) {
998                 rc = -ENOMEM;
999                 goto out;
1000         }
1001
1002         res = &qp->resp.resources[qp->resp.res_head];
1003         free_rd_atomic_resource(qp, res);
1004         rxe_advance_resp_resource(qp);
1005
1006         memcpy(SKB_TO_PKT(skb), &ack_pkt, sizeof(ack_pkt));
1007         memset((unsigned char *)SKB_TO_PKT(skb) + sizeof(ack_pkt), 0,
1008                sizeof(skb->cb) - sizeof(ack_pkt));
1009
1010         skb_get(skb);
1011         res->type = RXE_ATOMIC_MASK;
1012         res->atomic.skb = skb;
1013         res->first_psn = ack_pkt.psn;
1014         res->last_psn  = ack_pkt.psn;
1015         res->cur_psn   = ack_pkt.psn;
1016
1017         rc = rxe_xmit_packet(rxe, qp, &ack_pkt, skb);
1018         if (rc) {
1019                 pr_err_ratelimited("Failed sending ack\n");
1020                 rxe_drop_ref(qp);
1021         }
1022 out:
1023         return rc;
1024 }
1025
1026 static enum resp_states acknowledge(struct rxe_qp *qp,
1027                                     struct rxe_pkt_info *pkt)
1028 {
1029         if (qp_type(qp) != IB_QPT_RC)
1030                 return RESPST_CLEANUP;
1031
1032         if (qp->resp.aeth_syndrome != AETH_ACK_UNLIMITED)
1033                 send_ack(qp, pkt, qp->resp.aeth_syndrome, pkt->psn);
1034         else if (pkt->mask & RXE_ATOMIC_MASK)
1035                 send_atomic_ack(qp, pkt, AETH_ACK_UNLIMITED);
1036         else if (bth_ack(pkt))
1037                 send_ack(qp, pkt, AETH_ACK_UNLIMITED, pkt->psn);
1038
1039         return RESPST_CLEANUP;
1040 }
1041
1042 static enum resp_states cleanup(struct rxe_qp *qp,
1043                                 struct rxe_pkt_info *pkt)
1044 {
1045         struct sk_buff *skb;
1046
1047         if (pkt) {
1048                 skb = skb_dequeue(&qp->req_pkts);
1049                 rxe_drop_ref(qp);
1050                 kfree_skb(skb);
1051         }
1052
1053         if (qp->resp.mr) {
1054                 rxe_drop_ref(qp->resp.mr);
1055                 qp->resp.mr = NULL;
1056         }
1057
1058         return RESPST_DONE;
1059 }
1060
1061 static struct resp_res *find_resource(struct rxe_qp *qp, u32 psn)
1062 {
1063         int i;
1064
1065         for (i = 0; i < qp->attr.max_dest_rd_atomic; i++) {
1066                 struct resp_res *res = &qp->resp.resources[i];
1067
1068                 if (res->type == 0)
1069                         continue;
1070
1071                 if (psn_compare(psn, res->first_psn) >= 0 &&
1072                     psn_compare(psn, res->last_psn) <= 0) {
1073                         return res;
1074                 }
1075         }
1076
1077         return NULL;
1078 }
1079
1080 static enum resp_states duplicate_request(struct rxe_qp *qp,
1081                                           struct rxe_pkt_info *pkt)
1082 {
1083         enum resp_states rc;
1084         u32 prev_psn = (qp->resp.ack_psn - 1) & BTH_PSN_MASK;
1085
1086         if (pkt->mask & RXE_SEND_MASK ||
1087             pkt->mask & RXE_WRITE_MASK) {
1088                 /* SEND. Ack again and cleanup. C9-105. */
1089                 if (bth_ack(pkt))
1090                         send_ack(qp, pkt, AETH_ACK_UNLIMITED, prev_psn);
1091                 rc = RESPST_CLEANUP;
1092                 goto out;
1093         } else if (pkt->mask & RXE_READ_MASK) {
1094                 struct resp_res *res;
1095
1096                 res = find_resource(qp, pkt->psn);
1097                 if (!res) {
1098                         /* Resource not found. Class D error.  Drop the
1099                          * request.
1100                          */
1101                         rc = RESPST_CLEANUP;
1102                         goto out;
1103                 } else {
1104                         /* Ensure this new request is the same as the previous
1105                          * one or a subset of it.
1106                          */
1107                         u64 iova = reth_va(pkt);
1108                         u32 resid = reth_len(pkt);
1109
1110                         if (iova < res->read.va_org ||
1111                             resid > res->read.length ||
1112                             (iova + resid) > (res->read.va_org +
1113                                               res->read.length)) {
1114                                 rc = RESPST_CLEANUP;
1115                                 goto out;
1116                         }
1117
1118                         if (reth_rkey(pkt) != res->read.rkey) {
1119                                 rc = RESPST_CLEANUP;
1120                                 goto out;
1121                         }
1122
1123                         res->cur_psn = pkt->psn;
1124                         res->state = (pkt->psn == res->first_psn) ?
1125                                         rdatm_res_state_new :
1126                                         rdatm_res_state_replay;
1127                         res->replay = 1;
1128
1129                         /* Reset the resource, except length. */
1130                         res->read.va_org = iova;
1131                         res->read.va = iova;
1132                         res->read.resid = resid;
1133
1134                         /* Replay the RDMA read reply. */
1135                         qp->resp.res = res;
1136                         rc = RESPST_READ_REPLY;
1137                         goto out;
1138                 }
1139         } else {
1140                 struct resp_res *res;
1141
1142                 /* Find the operation in our list of responder resources. */
1143                 res = find_resource(qp, pkt->psn);
1144                 if (res) {
1145                         skb_get(res->atomic.skb);
1146                         /* Resend the result. */
1147                         rc = rxe_xmit_packet(to_rdev(qp->ibqp.device), qp,
1148                                              pkt, res->atomic.skb);
1149                         if (rc) {
1150                                 pr_err("Failed resending result. This flow is not handled - skb ignored\n");
1151                                 rc = RESPST_CLEANUP;
1152                                 goto out;
1153                         }
1154                 }
1155
1156                 /* Resource not found. Class D error. Drop the request. */
1157                 rc = RESPST_CLEANUP;
1158                 goto out;
1159         }
1160 out:
1161         return rc;
1162 }
1163
1164 /* Process a class A or C. Both are treated the same in this implementation. */
1165 static void do_class_ac_error(struct rxe_qp *qp, u8 syndrome,
1166                               enum ib_wc_status status)
1167 {
1168         qp->resp.aeth_syndrome  = syndrome;
1169         qp->resp.status         = status;
1170
1171         /* indicate that we should go through the ERROR state */
1172         qp->resp.goto_error     = 1;
1173 }
1174
1175 static enum resp_states do_class_d1e_error(struct rxe_qp *qp)
1176 {
1177         /* UC */
1178         if (qp->srq) {
1179                 /* Class E */
1180                 qp->resp.drop_msg = 1;
1181                 if (qp->resp.wqe) {
1182                         qp->resp.status = IB_WC_REM_INV_REQ_ERR;
1183                         return RESPST_COMPLETE;
1184                 } else {
1185                         return RESPST_CLEANUP;
1186                 }
1187         } else {
1188                 /* Class D1. This packet may be the start of a
1189                  * new message and could be valid. The previous
1190                  * message is invalid and ignored. reset the
1191                  * recv wr to its original state
1192                  */
1193                 if (qp->resp.wqe) {
1194                         qp->resp.wqe->dma.resid = qp->resp.wqe->dma.length;
1195                         qp->resp.wqe->dma.cur_sge = 0;
1196                         qp->resp.wqe->dma.sge_offset = 0;
1197                         qp->resp.opcode = -1;
1198                 }
1199
1200                 if (qp->resp.mr) {
1201                         rxe_drop_ref(qp->resp.mr);
1202                         qp->resp.mr = NULL;
1203                 }
1204
1205                 return RESPST_CLEANUP;
1206         }
1207 }
1208
1209 static void rxe_drain_req_pkts(struct rxe_qp *qp, bool notify)
1210 {
1211         struct sk_buff *skb;
1212
1213         while ((skb = skb_dequeue(&qp->req_pkts))) {
1214                 rxe_drop_ref(qp);
1215                 kfree_skb(skb);
1216         }
1217
1218         if (notify)
1219                 return;
1220
1221         while (!qp->srq && qp->rq.queue && queue_head(qp->rq.queue))
1222                 advance_consumer(qp->rq.queue);
1223 }
1224
1225 int rxe_responder(void *arg)
1226 {
1227         struct rxe_qp *qp = (struct rxe_qp *)arg;
1228         struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
1229         enum resp_states state;
1230         struct rxe_pkt_info *pkt = NULL;
1231         int ret = 0;
1232
1233         rxe_add_ref(qp);
1234
1235         qp->resp.aeth_syndrome = AETH_ACK_UNLIMITED;
1236
1237         if (!qp->valid) {
1238                 ret = -EINVAL;
1239                 goto done;
1240         }
1241
1242         switch (qp->resp.state) {
1243         case QP_STATE_RESET:
1244                 state = RESPST_RESET;
1245                 break;
1246
1247         default:
1248                 state = RESPST_GET_REQ;
1249                 break;
1250         }
1251
1252         while (1) {
1253                 pr_debug("qp#%d state = %s\n", qp_num(qp),
1254                          resp_state_name[state]);
1255                 switch (state) {
1256                 case RESPST_GET_REQ:
1257                         state = get_req(qp, &pkt);
1258                         break;
1259                 case RESPST_CHK_PSN:
1260                         state = check_psn(qp, pkt);
1261                         break;
1262                 case RESPST_CHK_OP_SEQ:
1263                         state = check_op_seq(qp, pkt);
1264                         break;
1265                 case RESPST_CHK_OP_VALID:
1266                         state = check_op_valid(qp, pkt);
1267                         break;
1268                 case RESPST_CHK_RESOURCE:
1269                         state = check_resource(qp, pkt);
1270                         break;
1271                 case RESPST_CHK_LENGTH:
1272                         state = check_length(qp, pkt);
1273                         break;
1274                 case RESPST_CHK_RKEY:
1275                         state = check_rkey(qp, pkt);
1276                         break;
1277                 case RESPST_EXECUTE:
1278                         state = execute(qp, pkt);
1279                         break;
1280                 case RESPST_COMPLETE:
1281                         state = do_complete(qp, pkt);
1282                         break;
1283                 case RESPST_READ_REPLY:
1284                         state = read_reply(qp, pkt);
1285                         break;
1286                 case RESPST_ACKNOWLEDGE:
1287                         state = acknowledge(qp, pkt);
1288                         break;
1289                 case RESPST_CLEANUP:
1290                         state = cleanup(qp, pkt);
1291                         break;
1292                 case RESPST_DUPLICATE_REQUEST:
1293                         state = duplicate_request(qp, pkt);
1294                         break;
1295                 case RESPST_ERR_PSN_OUT_OF_SEQ:
1296                         /* RC only - Class B. Drop packet. */
1297                         send_ack(qp, pkt, AETH_NAK_PSN_SEQ_ERROR, qp->resp.psn);
1298                         state = RESPST_CLEANUP;
1299                         break;
1300
1301                 case RESPST_ERR_TOO_MANY_RDMA_ATM_REQ:
1302                 case RESPST_ERR_MISSING_OPCODE_FIRST:
1303                 case RESPST_ERR_MISSING_OPCODE_LAST_C:
1304                 case RESPST_ERR_UNSUPPORTED_OPCODE:
1305                 case RESPST_ERR_MISALIGNED_ATOMIC:
1306                         /* RC Only - Class C. */
1307                         do_class_ac_error(qp, AETH_NAK_INVALID_REQ,
1308                                           IB_WC_REM_INV_REQ_ERR);
1309                         state = RESPST_COMPLETE;
1310                         break;
1311
1312                 case RESPST_ERR_MISSING_OPCODE_LAST_D1E:
1313                         state = do_class_d1e_error(qp);
1314                         break;
1315                 case RESPST_ERR_RNR:
1316                         if (qp_type(qp) == IB_QPT_RC) {
1317                                 rxe_counter_inc(rxe, RXE_CNT_SND_RNR);
1318                                 /* RC - class B */
1319                                 send_ack(qp, pkt, AETH_RNR_NAK |
1320                                          (~AETH_TYPE_MASK &
1321                                          qp->attr.min_rnr_timer),
1322                                          pkt->psn);
1323                         } else {
1324                                 /* UD/UC - class D */
1325                                 qp->resp.drop_msg = 1;
1326                         }
1327                         state = RESPST_CLEANUP;
1328                         break;
1329
1330                 case RESPST_ERR_RKEY_VIOLATION:
1331                         if (qp_type(qp) == IB_QPT_RC) {
1332                                 /* Class C */
1333                                 do_class_ac_error(qp, AETH_NAK_REM_ACC_ERR,
1334                                                   IB_WC_REM_ACCESS_ERR);
1335                                 state = RESPST_COMPLETE;
1336                         } else {
1337                                 qp->resp.drop_msg = 1;
1338                                 if (qp->srq) {
1339                                         /* UC/SRQ Class D */
1340                                         qp->resp.status = IB_WC_REM_ACCESS_ERR;
1341                                         state = RESPST_COMPLETE;
1342                                 } else {
1343                                         /* UC/non-SRQ Class E. */
1344                                         state = RESPST_CLEANUP;
1345                                 }
1346                         }
1347                         break;
1348
1349                 case RESPST_ERR_LENGTH:
1350                         if (qp_type(qp) == IB_QPT_RC) {
1351                                 /* Class C */
1352                                 do_class_ac_error(qp, AETH_NAK_INVALID_REQ,
1353                                                   IB_WC_REM_INV_REQ_ERR);
1354                                 state = RESPST_COMPLETE;
1355                         } else if (qp->srq) {
1356                                 /* UC/UD - class E */
1357                                 qp->resp.status = IB_WC_REM_INV_REQ_ERR;
1358                                 state = RESPST_COMPLETE;
1359                         } else {
1360                                 /* UC/UD - class D */
1361                                 qp->resp.drop_msg = 1;
1362                                 state = RESPST_CLEANUP;
1363                         }
1364                         break;
1365
1366                 case RESPST_ERR_MALFORMED_WQE:
1367                         /* All, Class A. */
1368                         do_class_ac_error(qp, AETH_NAK_REM_OP_ERR,
1369                                           IB_WC_LOC_QP_OP_ERR);
1370                         state = RESPST_COMPLETE;
1371                         break;
1372
1373                 case RESPST_ERR_CQ_OVERFLOW:
1374                         /* All - Class G */
1375                         state = RESPST_ERROR;
1376                         break;
1377
1378                 case RESPST_DONE:
1379                         if (qp->resp.goto_error) {
1380                                 state = RESPST_ERROR;
1381                                 break;
1382                         }
1383
1384                         goto done;
1385
1386                 case RESPST_EXIT:
1387                         if (qp->resp.goto_error) {
1388                                 state = RESPST_ERROR;
1389                                 break;
1390                         }
1391
1392                         goto exit;
1393
1394                 case RESPST_RESET:
1395                         rxe_drain_req_pkts(qp, false);
1396                         qp->resp.wqe = NULL;
1397                         goto exit;
1398
1399                 case RESPST_ERROR:
1400                         qp->resp.goto_error = 0;
1401                         pr_warn("qp#%d moved to error state\n", qp_num(qp));
1402                         rxe_qp_error(qp);
1403                         goto exit;
1404
1405                 default:
1406                         WARN_ON_ONCE(1);
1407                 }
1408         }
1409
1410 exit:
1411         ret = -EAGAIN;
1412 done:
1413         rxe_drop_ref(qp);
1414         return ret;
1415 }