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x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU...
[cris-mirror.git] / drivers / infiniband / hw / qib / qib_rc.c
blobc9955d48c50f412f762c9b5c7112103db0baf0a4
1 /*
2 * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
3 * Copyright (c) 2005, 2006 PathScale, 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/io.h>
35
36 #include "qib.h"
37
38 /* cut down ridiculously long IB macro names */
39 #define OP(x) IB_OPCODE_RC_##x
40
41
42 static u32 restart_sge(struct rvt_sge_state *ss, struct rvt_swqe *wqe,
43 u32 psn, u32 pmtu)
44 {
45 u32 len;
46
47 len = ((psn - wqe->psn) & QIB_PSN_MASK) * pmtu;
48 ss->sge = wqe->sg_list[0];
49 ss->sg_list = wqe->sg_list + 1;
50 ss->num_sge = wqe->wr.num_sge;
51 ss->total_len = wqe->length;
52 rvt_skip_sge(ss, len, false);
53 return wqe->length - len;
54 }
55
56 /**
57 * qib_make_rc_ack - construct a response packet (ACK, NAK, or RDMA read)
58 * @dev: the device for this QP
59 * @qp: a pointer to the QP
60 * @ohdr: a pointer to the IB header being constructed
61 * @pmtu: the path MTU
62 *
63 * Return 1 if constructed; otherwise, return 0.
64 * Note that we are in the responder's side of the QP context.
65 * Note the QP s_lock must be held.
66 */
67 static int qib_make_rc_ack(struct qib_ibdev *dev, struct rvt_qp *qp,
68 struct ib_other_headers *ohdr, u32 pmtu)
69 {
70 struct rvt_ack_entry *e;
71 u32 hwords;
72 u32 len;
73 u32 bth0;
74 u32 bth2;
75
76 /* Don't send an ACK if we aren't supposed to. */
77 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
78 goto bail;
79
80 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
81 hwords = 5;
82
83 switch (qp->s_ack_state) {
84 case OP(RDMA_READ_RESPONSE_LAST):
85 case OP(RDMA_READ_RESPONSE_ONLY):
86 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
87 if (e->rdma_sge.mr) {
88 rvt_put_mr(e->rdma_sge.mr);
89 e->rdma_sge.mr = NULL;
90 }
91 /* FALLTHROUGH */
92 case OP(ATOMIC_ACKNOWLEDGE):
93 /*
94 * We can increment the tail pointer now that the last
95 * response has been sent instead of only being
96 * constructed.
97 */
98 if (++qp->s_tail_ack_queue > QIB_MAX_RDMA_ATOMIC)
99 qp->s_tail_ack_queue = 0;
100 /* FALLTHROUGH */
101 case OP(SEND_ONLY):
102 case OP(ACKNOWLEDGE):
103 /* Check for no next entry in the queue. */
104 if (qp->r_head_ack_queue == qp->s_tail_ack_queue) {
105 if (qp->s_flags & RVT_S_ACK_PENDING)
106 goto normal;
107 goto bail;
108 }
109
110 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
111 if (e->opcode == OP(RDMA_READ_REQUEST)) {
112 /*
113 * If a RDMA read response is being resent and
114 * we haven't seen the duplicate request yet,
115 * then stop sending the remaining responses the
116 * responder has seen until the requester resends it.
117 */
118 len = e->rdma_sge.sge_length;
119 if (len && !e->rdma_sge.mr) {
120 qp->s_tail_ack_queue = qp->r_head_ack_queue;
121 goto bail;
122 }
123 /* Copy SGE state in case we need to resend */
124 qp->s_rdma_mr = e->rdma_sge.mr;
125 if (qp->s_rdma_mr)
126 rvt_get_mr(qp->s_rdma_mr);
127 qp->s_ack_rdma_sge.sge = e->rdma_sge;
128 qp->s_ack_rdma_sge.num_sge = 1;
129 qp->s_cur_sge = &qp->s_ack_rdma_sge;
130 if (len > pmtu) {
131 len = pmtu;
132 qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST);
133 } else {
134 qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY);
135 e->sent = 1;
136 }
137 ohdr->u.aeth = rvt_compute_aeth(qp);
138 hwords++;
139 qp->s_ack_rdma_psn = e->psn;
140 bth2 = qp->s_ack_rdma_psn++ & QIB_PSN_MASK;
141 } else {
142 /* COMPARE_SWAP or FETCH_ADD */
143 qp->s_cur_sge = NULL;
144 len = 0;
145 qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
146 ohdr->u.at.aeth = rvt_compute_aeth(qp);
147 ib_u64_put(e->atomic_data, &ohdr->u.at.atomic_ack_eth);
148 hwords += sizeof(ohdr->u.at) / sizeof(u32);
149 bth2 = e->psn & QIB_PSN_MASK;
150 e->sent = 1;
151 }
152 bth0 = qp->s_ack_state << 24;
153 break;
154
155 case OP(RDMA_READ_RESPONSE_FIRST):
156 qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE);
157 /* FALLTHROUGH */
158 case OP(RDMA_READ_RESPONSE_MIDDLE):
159 qp->s_cur_sge = &qp->s_ack_rdma_sge;
160 qp->s_rdma_mr = qp->s_ack_rdma_sge.sge.mr;
161 if (qp->s_rdma_mr)
162 rvt_get_mr(qp->s_rdma_mr);
163 len = qp->s_ack_rdma_sge.sge.sge_length;
164 if (len > pmtu)
165 len = pmtu;
166 else {
167 ohdr->u.aeth = rvt_compute_aeth(qp);
168 hwords++;
169 qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
170 e = &qp->s_ack_queue[qp->s_tail_ack_queue];
171 e->sent = 1;
172 }
173 bth0 = qp->s_ack_state << 24;
174 bth2 = qp->s_ack_rdma_psn++ & QIB_PSN_MASK;
175 break;
176
177 default:
178 normal:
179 /*
180 * Send a regular ACK.
181 * Set the s_ack_state so we wait until after sending
182 * the ACK before setting s_ack_state to ACKNOWLEDGE
183 * (see above).
184 */
185 qp->s_ack_state = OP(SEND_ONLY);
186 qp->s_flags &= ~RVT_S_ACK_PENDING;
187 qp->s_cur_sge = NULL;
188 if (qp->s_nak_state)
189 ohdr->u.aeth =
190 cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
191 (qp->s_nak_state <<
192 IB_AETH_CREDIT_SHIFT));
193 else
194 ohdr->u.aeth = rvt_compute_aeth(qp);
195 hwords++;
196 len = 0;
197 bth0 = OP(ACKNOWLEDGE) << 24;
198 bth2 = qp->s_ack_psn & QIB_PSN_MASK;
199 }
200 qp->s_rdma_ack_cnt++;
201 qp->s_hdrwords = hwords;
202 qp->s_cur_size = len;
203 qib_make_ruc_header(qp, ohdr, bth0, bth2);
204 return 1;
205
206 bail:
207 qp->s_ack_state = OP(ACKNOWLEDGE);
208 qp->s_flags &= ~(RVT_S_RESP_PENDING | RVT_S_ACK_PENDING);
209 return 0;
210 }
211
212 /**
213 * qib_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC)
214 * @qp: a pointer to the QP
215 *
216 * Assumes the s_lock is held.
217 *
218 * Return 1 if constructed; otherwise, return 0.
219 */
220 int qib_make_rc_req(struct rvt_qp *qp, unsigned long *flags)
221 {
222 struct qib_qp_priv *priv = qp->priv;
223 struct qib_ibdev *dev = to_idev(qp->ibqp.device);
224 struct ib_other_headers *ohdr;
225 struct rvt_sge_state *ss;
226 struct rvt_swqe *wqe;
227 u32 hwords;
228 u32 len;
229 u32 bth0;
230 u32 bth2;
231 u32 pmtu = qp->pmtu;
232 char newreq;
233 int ret = 0;
234 int delta;
235
236 ohdr = &priv->s_hdr->u.oth;
237 if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)
238 ohdr = &priv->s_hdr->u.l.oth;
239
240 /* Sending responses has higher priority over sending requests. */
241 if ((qp->s_flags & RVT_S_RESP_PENDING) &&
242 qib_make_rc_ack(dev, qp, ohdr, pmtu))
243 goto done;
244
245 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
246 if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND))
247 goto bail;
248 /* We are in the error state, flush the work request. */
249 if (qp->s_last == READ_ONCE(qp->s_head))
250 goto bail;
251 /* If DMAs are in progress, we can't flush immediately. */
252 if (atomic_read(&priv->s_dma_busy)) {
253 qp->s_flags |= RVT_S_WAIT_DMA;
254 goto bail;
255 }
256 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
257 qib_send_complete(qp, wqe, qp->s_last != qp->s_acked ?
258 IB_WC_SUCCESS : IB_WC_WR_FLUSH_ERR);
259 /* will get called again */
260 goto done;
261 }
262
263 if (qp->s_flags & (RVT_S_WAIT_RNR | RVT_S_WAIT_ACK))
264 goto bail;
265
266 if (qib_cmp24(qp->s_psn, qp->s_sending_hpsn) <= 0) {
267 if (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0) {
268 qp->s_flags |= RVT_S_WAIT_PSN;
269 goto bail;
270 }
271 qp->s_sending_psn = qp->s_psn;
272 qp->s_sending_hpsn = qp->s_psn - 1;
273 }
274
275 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
276 hwords = 5;
277 bth0 = 0;
278
279 /* Send a request. */
280 wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
281 switch (qp->s_state) {
282 default:
283 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_NEXT_SEND_OK))
284 goto bail;
285 /*
286 * Resend an old request or start a new one.
287 *
288 * We keep track of the current SWQE so that
289 * we don't reset the "furthest progress" state
290 * if we need to back up.
291 */
292 newreq = 0;
293 if (qp->s_cur == qp->s_tail) {
294 /* Check if send work queue is empty. */
295 if (qp->s_tail == READ_ONCE(qp->s_head))
296 goto bail;
297 /*
298 * If a fence is requested, wait for previous
299 * RDMA read and atomic operations to finish.
300 */
301 if ((wqe->wr.send_flags & IB_SEND_FENCE) &&
302 qp->s_num_rd_atomic) {
303 qp->s_flags |= RVT_S_WAIT_FENCE;
304 goto bail;
305 }
306 newreq = 1;
307 qp->s_psn = wqe->psn;
308 }
309 /*
310 * Note that we have to be careful not to modify the
311 * original work request since we may need to resend
312 * it.
313 */
314 len = wqe->length;
315 ss = &qp->s_sge;
316 bth2 = qp->s_psn & QIB_PSN_MASK;
317 switch (wqe->wr.opcode) {
318 case IB_WR_SEND:
319 case IB_WR_SEND_WITH_IMM:
320 /* If no credit, return. */
321 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
322 rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
323 qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
324 goto bail;
325 }
326 if (len > pmtu) {
327 qp->s_state = OP(SEND_FIRST);
328 len = pmtu;
329 break;
330 }
331 if (wqe->wr.opcode == IB_WR_SEND)
332 qp->s_state = OP(SEND_ONLY);
333 else {
334 qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE);
335 /* Immediate data comes after the BTH */
336 ohdr->u.imm_data = wqe->wr.ex.imm_data;
337 hwords += 1;
338 }
339 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
340 bth0 |= IB_BTH_SOLICITED;
341 bth2 |= IB_BTH_REQ_ACK;
342 if (++qp->s_cur == qp->s_size)
343 qp->s_cur = 0;
344 break;
345
346 case IB_WR_RDMA_WRITE:
347 if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
348 qp->s_lsn++;
349 goto no_flow_control;
350 case IB_WR_RDMA_WRITE_WITH_IMM:
351 /* If no credit, return. */
352 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
353 rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
354 qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
355 goto bail;
356 }
357 no_flow_control:
358 ohdr->u.rc.reth.vaddr =
359 cpu_to_be64(wqe->rdma_wr.remote_addr);
360 ohdr->u.rc.reth.rkey =
361 cpu_to_be32(wqe->rdma_wr.rkey);
362 ohdr->u.rc.reth.length = cpu_to_be32(len);
363 hwords += sizeof(struct ib_reth) / sizeof(u32);
364 if (len > pmtu) {
365 qp->s_state = OP(RDMA_WRITE_FIRST);
366 len = pmtu;
367 break;
368 }
369 if (wqe->rdma_wr.wr.opcode == IB_WR_RDMA_WRITE)
370 qp->s_state = OP(RDMA_WRITE_ONLY);
371 else {
372 qp->s_state = OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE);
373 /* Immediate data comes after RETH */
374 ohdr->u.rc.imm_data =
375 wqe->rdma_wr.wr.ex.imm_data;
376 hwords += 1;
377 if (wqe->rdma_wr.wr.send_flags & IB_SEND_SOLICITED)
378 bth0 |= IB_BTH_SOLICITED;
379 }
380 bth2 |= IB_BTH_REQ_ACK;
381 if (++qp->s_cur == qp->s_size)
382 qp->s_cur = 0;
383 break;
384
385 case IB_WR_RDMA_READ:
386 /*
387 * Don't allow more operations to be started
388 * than the QP limits allow.
389 */
390 if (newreq) {
391 if (qp->s_num_rd_atomic >=
392 qp->s_max_rd_atomic) {
393 qp->s_flags |= RVT_S_WAIT_RDMAR;
394 goto bail;
395 }
396 qp->s_num_rd_atomic++;
397 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
398 qp->s_lsn++;
399 }
400
401 ohdr->u.rc.reth.vaddr =
402 cpu_to_be64(wqe->rdma_wr.remote_addr);
403 ohdr->u.rc.reth.rkey =
404 cpu_to_be32(wqe->rdma_wr.rkey);
405 ohdr->u.rc.reth.length = cpu_to_be32(len);
406 qp->s_state = OP(RDMA_READ_REQUEST);
407 hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
408 ss = NULL;
409 len = 0;
410 bth2 |= IB_BTH_REQ_ACK;
411 if (++qp->s_cur == qp->s_size)
412 qp->s_cur = 0;
413 break;
414
415 case IB_WR_ATOMIC_CMP_AND_SWP:
416 case IB_WR_ATOMIC_FETCH_AND_ADD:
417 /*
418 * Don't allow more operations to be started
419 * than the QP limits allow.
420 */
421 if (newreq) {
422 if (qp->s_num_rd_atomic >=
423 qp->s_max_rd_atomic) {
424 qp->s_flags |= RVT_S_WAIT_RDMAR;
425 goto bail;
426 }
427 qp->s_num_rd_atomic++;
428 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
429 qp->s_lsn++;
430 }
431 if (wqe->atomic_wr.wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP) {
432 qp->s_state = OP(COMPARE_SWAP);
433 put_ib_ateth_swap(wqe->atomic_wr.swap,
434 &ohdr->u.atomic_eth);
435 put_ib_ateth_compare(wqe->atomic_wr.compare_add,
436 &ohdr->u.atomic_eth);
437 } else {
438 qp->s_state = OP(FETCH_ADD);
439 put_ib_ateth_swap(wqe->atomic_wr.compare_add,
440 &ohdr->u.atomic_eth);
441 put_ib_ateth_compare(0, &ohdr->u.atomic_eth);
442 }
443 put_ib_ateth_vaddr(wqe->atomic_wr.remote_addr,
444 &ohdr->u.atomic_eth);
445 ohdr->u.atomic_eth.rkey = cpu_to_be32(
446 wqe->atomic_wr.rkey);
447 hwords += sizeof(struct ib_atomic_eth) / sizeof(u32);
448 ss = NULL;
449 len = 0;
450 bth2 |= IB_BTH_REQ_ACK;
451 if (++qp->s_cur == qp->s_size)
452 qp->s_cur = 0;
453 break;
454
455 default:
456 goto bail;
457 }
458 qp->s_sge.sge = wqe->sg_list[0];
459 qp->s_sge.sg_list = wqe->sg_list + 1;
460 qp->s_sge.num_sge = wqe->wr.num_sge;
461 qp->s_sge.total_len = wqe->length;
462 qp->s_len = wqe->length;
463 if (newreq) {
464 qp->s_tail++;
465 if (qp->s_tail >= qp->s_size)
466 qp->s_tail = 0;
467 }
468 if (wqe->wr.opcode == IB_WR_RDMA_READ)
469 qp->s_psn = wqe->lpsn + 1;
470 else
471 qp->s_psn++;
472 break;
473
474 case OP(RDMA_READ_RESPONSE_FIRST):
475 /*
476 * qp->s_state is normally set to the opcode of the
477 * last packet constructed for new requests and therefore
478 * is never set to RDMA read response.
479 * RDMA_READ_RESPONSE_FIRST is used by the ACK processing
480 * thread to indicate a SEND needs to be restarted from an
481 * earlier PSN without interferring with the sending thread.
482 * See qib_restart_rc().
483 */
484 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
485 /* FALLTHROUGH */
486 case OP(SEND_FIRST):
487 qp->s_state = OP(SEND_MIDDLE);
488 /* FALLTHROUGH */
489 case OP(SEND_MIDDLE):
490 bth2 = qp->s_psn++ & QIB_PSN_MASK;
491 ss = &qp->s_sge;
492 len = qp->s_len;
493 if (len > pmtu) {
494 len = pmtu;
495 break;
496 }
497 if (wqe->wr.opcode == IB_WR_SEND)
498 qp->s_state = OP(SEND_LAST);
499 else {
500 qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE);
501 /* Immediate data comes after the BTH */
502 ohdr->u.imm_data = wqe->wr.ex.imm_data;
503 hwords += 1;
504 }
505 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
506 bth0 |= IB_BTH_SOLICITED;
507 bth2 |= IB_BTH_REQ_ACK;
508 qp->s_cur++;
509 if (qp->s_cur >= qp->s_size)
510 qp->s_cur = 0;
511 break;
512
513 case OP(RDMA_READ_RESPONSE_LAST):
514 /*
515 * qp->s_state is normally set to the opcode of the
516 * last packet constructed for new requests and therefore
517 * is never set to RDMA read response.
518 * RDMA_READ_RESPONSE_LAST is used by the ACK processing
519 * thread to indicate a RDMA write needs to be restarted from
520 * an earlier PSN without interferring with the sending thread.
521 * See qib_restart_rc().
522 */
523 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
524 /* FALLTHROUGH */
525 case OP(RDMA_WRITE_FIRST):
526 qp->s_state = OP(RDMA_WRITE_MIDDLE);
527 /* FALLTHROUGH */
528 case OP(RDMA_WRITE_MIDDLE):
529 bth2 = qp->s_psn++ & QIB_PSN_MASK;
530 ss = &qp->s_sge;
531 len = qp->s_len;
532 if (len > pmtu) {
533 len = pmtu;
534 break;
535 }
536 if (wqe->wr.opcode == IB_WR_RDMA_WRITE)
537 qp->s_state = OP(RDMA_WRITE_LAST);
538 else {
539 qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE);
540 /* Immediate data comes after the BTH */
541 ohdr->u.imm_data = wqe->wr.ex.imm_data;
542 hwords += 1;
543 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
544 bth0 |= IB_BTH_SOLICITED;
545 }
546 bth2 |= IB_BTH_REQ_ACK;
547 qp->s_cur++;
548 if (qp->s_cur >= qp->s_size)
549 qp->s_cur = 0;
550 break;
551
552 case OP(RDMA_READ_RESPONSE_MIDDLE):
553 /*
554 * qp->s_state is normally set to the opcode of the
555 * last packet constructed for new requests and therefore
556 * is never set to RDMA read response.
557 * RDMA_READ_RESPONSE_MIDDLE is used by the ACK processing
558 * thread to indicate a RDMA read needs to be restarted from
559 * an earlier PSN without interferring with the sending thread.
560 * See qib_restart_rc().
561 */
562 len = ((qp->s_psn - wqe->psn) & QIB_PSN_MASK) * pmtu;
563 ohdr->u.rc.reth.vaddr =
564 cpu_to_be64(wqe->rdma_wr.remote_addr + len);
565 ohdr->u.rc.reth.rkey =
566 cpu_to_be32(wqe->rdma_wr.rkey);
567 ohdr->u.rc.reth.length = cpu_to_be32(wqe->length - len);
568 qp->s_state = OP(RDMA_READ_REQUEST);
569 hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
570 bth2 = (qp->s_psn & QIB_PSN_MASK) | IB_BTH_REQ_ACK;
571 qp->s_psn = wqe->lpsn + 1;
572 ss = NULL;
573 len = 0;
574 qp->s_cur++;
575 if (qp->s_cur == qp->s_size)
576 qp->s_cur = 0;
577 break;
578 }
579 qp->s_sending_hpsn = bth2;
580 delta = (((int) bth2 - (int) wqe->psn) << 8) >> 8;
581 if (delta && delta % QIB_PSN_CREDIT == 0)
582 bth2 |= IB_BTH_REQ_ACK;
583 if (qp->s_flags & RVT_S_SEND_ONE) {
584 qp->s_flags &= ~RVT_S_SEND_ONE;
585 qp->s_flags |= RVT_S_WAIT_ACK;
586 bth2 |= IB_BTH_REQ_ACK;
587 }
588 qp->s_len -= len;
589 qp->s_hdrwords = hwords;
590 qp->s_cur_sge = ss;
591 qp->s_cur_size = len;
592 qib_make_ruc_header(qp, ohdr, bth0 | (qp->s_state << 24), bth2);
593 done:
594 return 1;
595 bail:
596 qp->s_flags &= ~RVT_S_BUSY;
597 return ret;
598 }
599
600 /**
601 * qib_send_rc_ack - Construct an ACK packet and send it
602 * @qp: a pointer to the QP
603 *
604 * This is called from qib_rc_rcv() and qib_kreceive().
605 * Note that RDMA reads and atomics are handled in the
606 * send side QP state and tasklet.
607 */
608 void qib_send_rc_ack(struct rvt_qp *qp)
609 {
610 struct qib_devdata *dd = dd_from_ibdev(qp->ibqp.device);
611 struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
612 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
613 u64 pbc;
614 u16 lrh0;
615 u32 bth0;
616 u32 hwords;
617 u32 pbufn;
618 u32 __iomem *piobuf;
619 struct ib_header hdr;
620 struct ib_other_headers *ohdr;
621 u32 control;
622 unsigned long flags;
623
624 spin_lock_irqsave(&qp->s_lock, flags);
625
626 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
627 goto unlock;
628
629 /* Don't send ACK or NAK if a RDMA read or atomic is pending. */
630 if ((qp->s_flags & RVT_S_RESP_PENDING) || qp->s_rdma_ack_cnt)
631 goto queue_ack;
632
633 /* Construct the header with s_lock held so APM doesn't change it. */
634 ohdr = &hdr.u.oth;
635 lrh0 = QIB_LRH_BTH;
636 /* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4. */
637 hwords = 6;
638 if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
639 IB_AH_GRH)) {
640 hwords += qib_make_grh(ibp, &hdr.u.l.grh,
641 rdma_ah_read_grh(&qp->remote_ah_attr),
642 hwords, 0);
643 ohdr = &hdr.u.l.oth;
644 lrh0 = QIB_LRH_GRH;
645 }
646 /* read pkey_index w/o lock (its atomic) */
647 bth0 = qib_get_pkey(ibp, qp->s_pkey_index) | (OP(ACKNOWLEDGE) << 24);
648 if (qp->s_mig_state == IB_MIG_MIGRATED)
649 bth0 |= IB_BTH_MIG_REQ;
650 if (qp->r_nak_state)
651 ohdr->u.aeth = cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
652 (qp->r_nak_state <<
653 IB_AETH_CREDIT_SHIFT));
654 else
655 ohdr->u.aeth = rvt_compute_aeth(qp);
656 lrh0 |= ibp->sl_to_vl[rdma_ah_get_sl(&qp->remote_ah_attr)] << 12 |
657 rdma_ah_get_sl(&qp->remote_ah_attr) << 4;
658 hdr.lrh[0] = cpu_to_be16(lrh0);
659 hdr.lrh[1] = cpu_to_be16(rdma_ah_get_dlid(&qp->remote_ah_attr));
660 hdr.lrh[2] = cpu_to_be16(hwords + SIZE_OF_CRC);
661 hdr.lrh[3] = cpu_to_be16(ppd->lid |
662 rdma_ah_get_path_bits(&qp->remote_ah_attr));
663 ohdr->bth[0] = cpu_to_be32(bth0);
664 ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
665 ohdr->bth[2] = cpu_to_be32(qp->r_ack_psn & QIB_PSN_MASK);
666
667 spin_unlock_irqrestore(&qp->s_lock, flags);
668
669 /* Don't try to send ACKs if the link isn't ACTIVE */
670 if (!(ppd->lflags & QIBL_LINKACTIVE))
671 goto done;
672
673 control = dd->f_setpbc_control(ppd, hwords + SIZE_OF_CRC,
674 qp->s_srate, lrh0 >> 12);
675 /* length is + 1 for the control dword */
676 pbc = ((u64) control << 32) | (hwords + 1);
677
678 piobuf = dd->f_getsendbuf(ppd, pbc, &pbufn);
679 if (!piobuf) {
680 /*
681 * We are out of PIO buffers at the moment.
682 * Pass responsibility for sending the ACK to the
683 * send tasklet so that when a PIO buffer becomes
684 * available, the ACK is sent ahead of other outgoing
685 * packets.
686 */
687 spin_lock_irqsave(&qp->s_lock, flags);
688 goto queue_ack;
689 }
690
691 /*
692 * Write the pbc.
693 * We have to flush after the PBC for correctness
694 * on some cpus or WC buffer can be written out of order.
695 */
696 writeq(pbc, piobuf);
697
698 if (dd->flags & QIB_PIO_FLUSH_WC) {
699 u32 *hdrp = (u32 *) &hdr;
700
701 qib_flush_wc();
702 qib_pio_copy(piobuf + 2, hdrp, hwords - 1);
703 qib_flush_wc();
704 __raw_writel(hdrp[hwords - 1], piobuf + hwords + 1);
705 } else
706 qib_pio_copy(piobuf + 2, (u32 *) &hdr, hwords);
707
708 if (dd->flags & QIB_USE_SPCL_TRIG) {
709 u32 spcl_off = (pbufn >= dd->piobcnt2k) ? 2047 : 1023;
710
711 qib_flush_wc();
712 __raw_writel(0xaebecede, piobuf + spcl_off);
713 }
714
715 qib_flush_wc();
716 qib_sendbuf_done(dd, pbufn);
717
718 this_cpu_inc(ibp->pmastats->n_unicast_xmit);
719 goto done;
720
721 queue_ack:
722 if (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) {
723 this_cpu_inc(*ibp->rvp.rc_qacks);
724 qp->s_flags |= RVT_S_ACK_PENDING | RVT_S_RESP_PENDING;
725 qp->s_nak_state = qp->r_nak_state;
726 qp->s_ack_psn = qp->r_ack_psn;
727
728 /* Schedule the send tasklet. */
729 qib_schedule_send(qp);
730 }
731 unlock:
732 spin_unlock_irqrestore(&qp->s_lock, flags);
733 done:
734 return;
735 }
736
737 /**
738 * reset_psn - reset the QP state to send starting from PSN
739 * @qp: the QP
740 * @psn: the packet sequence number to restart at
741 *
742 * This is called from qib_rc_rcv() to process an incoming RC ACK
743 * for the given QP.
744 * Called at interrupt level with the QP s_lock held.
745 */
746 static void reset_psn(struct rvt_qp *qp, u32 psn)
747 {
748 u32 n = qp->s_acked;
749 struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, n);
750 u32 opcode;
751
752 qp->s_cur = n;
753
754 /*
755 * If we are starting the request from the beginning,
756 * let the normal send code handle initialization.
757 */
758 if (qib_cmp24(psn, wqe->psn) <= 0) {
759 qp->s_state = OP(SEND_LAST);
760 goto done;
761 }
762
763 /* Find the work request opcode corresponding to the given PSN. */
764 opcode = wqe->wr.opcode;
765 for (;;) {
766 int diff;
767
768 if (++n == qp->s_size)
769 n = 0;
770 if (n == qp->s_tail)
771 break;
772 wqe = rvt_get_swqe_ptr(qp, n);
773 diff = qib_cmp24(psn, wqe->psn);
774 if (diff < 0)
775 break;
776 qp->s_cur = n;
777 /*
778 * If we are starting the request from the beginning,
779 * let the normal send code handle initialization.
780 */
781 if (diff == 0) {
782 qp->s_state = OP(SEND_LAST);
783 goto done;
784 }
785 opcode = wqe->wr.opcode;
786 }
787
788 /*
789 * Set the state to restart in the middle of a request.
790 * Don't change the s_sge, s_cur_sge, or s_cur_size.
791 * See qib_make_rc_req().
792 */
793 switch (opcode) {
794 case IB_WR_SEND:
795 case IB_WR_SEND_WITH_IMM:
796 qp->s_state = OP(RDMA_READ_RESPONSE_FIRST);
797 break;
798
799 case IB_WR_RDMA_WRITE:
800 case IB_WR_RDMA_WRITE_WITH_IMM:
801 qp->s_state = OP(RDMA_READ_RESPONSE_LAST);
802 break;
803
804 case IB_WR_RDMA_READ:
805 qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE);
806 break;
807
808 default:
809 /*
810 * This case shouldn't happen since its only
811 * one PSN per req.
812 */
813 qp->s_state = OP(SEND_LAST);
814 }
815 done:
816 qp->s_psn = psn;
817 /*
818 * Set RVT_S_WAIT_PSN as qib_rc_complete() may start the timer
819 * asynchronously before the send tasklet can get scheduled.
820 * Doing it in qib_make_rc_req() is too late.
821 */
822 if ((qib_cmp24(qp->s_psn, qp->s_sending_hpsn) <= 0) &&
823 (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0))
824 qp->s_flags |= RVT_S_WAIT_PSN;
825 }
826
827 /*
828 * Back up requester to resend the last un-ACKed request.
829 * The QP r_lock and s_lock should be held and interrupts disabled.
830 */
831 void qib_restart_rc(struct rvt_qp *qp, u32 psn, int wait)
832 {
833 struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
834 struct qib_ibport *ibp;
835
836 if (qp->s_retry == 0) {
837 if (qp->s_mig_state == IB_MIG_ARMED) {
838 qib_migrate_qp(qp);
839 qp->s_retry = qp->s_retry_cnt;
840 } else if (qp->s_last == qp->s_acked) {
841 qib_send_complete(qp, wqe, IB_WC_RETRY_EXC_ERR);
842 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
843 return;
844 } else /* XXX need to handle delayed completion */
845 return;
846 } else
847 qp->s_retry--;
848
849 ibp = to_iport(qp->ibqp.device, qp->port_num);
850 if (wqe->wr.opcode == IB_WR_RDMA_READ)
851 ibp->rvp.n_rc_resends++;
852 else
853 ibp->rvp.n_rc_resends += (qp->s_psn - psn) & QIB_PSN_MASK;
854
855 qp->s_flags &= ~(RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR |
856 RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_PSN |
857 RVT_S_WAIT_ACK);
858 if (wait)
859 qp->s_flags |= RVT_S_SEND_ONE;
860 reset_psn(qp, psn);
861 }
862
863 /*
864 * Set qp->s_sending_psn to the next PSN after the given one.
865 * This would be psn+1 except when RDMA reads are present.
866 */
867 static void reset_sending_psn(struct rvt_qp *qp, u32 psn)
868 {
869 struct rvt_swqe *wqe;
870 u32 n = qp->s_last;
871
872 /* Find the work request corresponding to the given PSN. */
873 for (;;) {
874 wqe = rvt_get_swqe_ptr(qp, n);
875 if (qib_cmp24(psn, wqe->lpsn) <= 0) {
876 if (wqe->wr.opcode == IB_WR_RDMA_READ)
877 qp->s_sending_psn = wqe->lpsn + 1;
878 else
879 qp->s_sending_psn = psn + 1;
880 break;
881 }
882 if (++n == qp->s_size)
883 n = 0;
884 if (n == qp->s_tail)
885 break;
886 }
887 }
888
889 /*
890 * This should be called with the QP s_lock held and interrupts disabled.
891 */
892 void qib_rc_send_complete(struct rvt_qp *qp, struct ib_header *hdr)
893 {
894 struct ib_other_headers *ohdr;
895 struct rvt_swqe *wqe;
896 u32 opcode;
897 u32 psn;
898
899 if (!(ib_rvt_state_ops[qp->state] & RVT_SEND_OR_FLUSH_OR_RECV_OK))
900 return;
901
902 /* Find out where the BTH is */
903 if ((be16_to_cpu(hdr->lrh[0]) & 3) == QIB_LRH_BTH)
904 ohdr = &hdr->u.oth;
905 else
906 ohdr = &hdr->u.l.oth;
907
908 opcode = be32_to_cpu(ohdr->bth[0]) >> 24;
909 if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
910 opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
911 WARN_ON(!qp->s_rdma_ack_cnt);
912 qp->s_rdma_ack_cnt--;
913 return;
914 }
915
916 psn = be32_to_cpu(ohdr->bth[2]);
917 reset_sending_psn(qp, psn);
918
919 /*
920 * Start timer after a packet requesting an ACK has been sent and
921 * there are still requests that haven't been acked.
922 */
923 if ((psn & IB_BTH_REQ_ACK) && qp->s_acked != qp->s_tail &&
924 !(qp->s_flags & (RVT_S_TIMER | RVT_S_WAIT_RNR | RVT_S_WAIT_PSN)) &&
925 (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
926 rvt_add_retry_timer(qp);
927
928 while (qp->s_last != qp->s_acked) {
929 u32 s_last;
930
931 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
932 if (qib_cmp24(wqe->lpsn, qp->s_sending_psn) >= 0 &&
933 qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)
934 break;
935 s_last = qp->s_last;
936 if (++s_last >= qp->s_size)
937 s_last = 0;
938 qp->s_last = s_last;
939 /* see post_send() */
940 barrier();
941 rvt_put_swqe(wqe);
942 rvt_qp_swqe_complete(qp,
943 wqe,
944 ib_qib_wc_opcode[wqe->wr.opcode],
945 IB_WC_SUCCESS);
946 }
947 /*
948 * If we were waiting for sends to complete before resending,
949 * and they are now complete, restart sending.
950 */
951 if (qp->s_flags & RVT_S_WAIT_PSN &&
952 qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
953 qp->s_flags &= ~RVT_S_WAIT_PSN;
954 qp->s_sending_psn = qp->s_psn;
955 qp->s_sending_hpsn = qp->s_psn - 1;
956 qib_schedule_send(qp);
957 }
958 }
959
960 static inline void update_last_psn(struct rvt_qp *qp, u32 psn)
961 {
962 qp->s_last_psn = psn;
963 }
964
965 /*
966 * Generate a SWQE completion.
967 * This is similar to qib_send_complete but has to check to be sure
968 * that the SGEs are not being referenced if the SWQE is being resent.
969 */
970 static struct rvt_swqe *do_rc_completion(struct rvt_qp *qp,
971 struct rvt_swqe *wqe,
972 struct qib_ibport *ibp)
973 {
974 /*
975 * Don't decrement refcount and don't generate a
976 * completion if the SWQE is being resent until the send
977 * is finished.
978 */
979 if (qib_cmp24(wqe->lpsn, qp->s_sending_psn) < 0 ||
980 qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
981 u32 s_last;
982
983 rvt_put_swqe(wqe);
984 s_last = qp->s_last;
985 if (++s_last >= qp->s_size)
986 s_last = 0;
987 qp->s_last = s_last;
988 /* see post_send() */
989 barrier();
990 rvt_qp_swqe_complete(qp,
991 wqe,
992 ib_qib_wc_opcode[wqe->wr.opcode],
993 IB_WC_SUCCESS);
994 } else
995 this_cpu_inc(*ibp->rvp.rc_delayed_comp);
996
997 qp->s_retry = qp->s_retry_cnt;
998 update_last_psn(qp, wqe->lpsn);
999
1000 /*
1001 * If we are completing a request which is in the process of
1002 * being resent, we can stop resending it since we know the
1003 * responder has already seen it.
1004 */
1005 if (qp->s_acked == qp->s_cur) {
1006 if (++qp->s_cur >= qp->s_size)
1007 qp->s_cur = 0;
1008 qp->s_acked = qp->s_cur;
1009 wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
1010 if (qp->s_acked != qp->s_tail) {
1011 qp->s_state = OP(SEND_LAST);
1012 qp->s_psn = wqe->psn;
1013 }
1014 } else {
1015 if (++qp->s_acked >= qp->s_size)
1016 qp->s_acked = 0;
1017 if (qp->state == IB_QPS_SQD && qp->s_acked == qp->s_cur)
1018 qp->s_draining = 0;
1019 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1020 }
1021 return wqe;
1022 }
1023
1024 /**
1025 * do_rc_ack - process an incoming RC ACK
1026 * @qp: the QP the ACK came in on
1027 * @psn: the packet sequence number of the ACK
1028 * @opcode: the opcode of the request that resulted in the ACK
1029 *
1030 * This is called from qib_rc_rcv_resp() to process an incoming RC ACK
1031 * for the given QP.
1032 * Called at interrupt level with the QP s_lock held.
1033 * Returns 1 if OK, 0 if current operation should be aborted (NAK).
1034 */
1035 static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
1036 u64 val, struct qib_ctxtdata *rcd)
1037 {
1038 struct qib_ibport *ibp;
1039 enum ib_wc_status status;
1040 struct rvt_swqe *wqe;
1041 int ret = 0;
1042 u32 ack_psn;
1043 int diff;
1044
1045 /*
1046 * Note that NAKs implicitly ACK outstanding SEND and RDMA write
1047 * requests and implicitly NAK RDMA read and atomic requests issued
1048 * before the NAK'ed request. The MSN won't include the NAK'ed
1049 * request but will include an ACK'ed request(s).
1050 */
1051 ack_psn = psn;
1052 if (aeth >> IB_AETH_NAK_SHIFT)
1053 ack_psn--;
1054 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1055 ibp = to_iport(qp->ibqp.device, qp->port_num);
1056
1057 /*
1058 * The MSN might be for a later WQE than the PSN indicates so
1059 * only complete WQEs that the PSN finishes.
1060 */
1061 while ((diff = qib_cmp24(ack_psn, wqe->lpsn)) >= 0) {
1062 /*
1063 * RDMA_READ_RESPONSE_ONLY is a special case since
1064 * we want to generate completion events for everything
1065 * before the RDMA read, copy the data, then generate
1066 * the completion for the read.
1067 */
1068 if (wqe->wr.opcode == IB_WR_RDMA_READ &&
1069 opcode == OP(RDMA_READ_RESPONSE_ONLY) &&
1070 diff == 0) {
1071 ret = 1;
1072 goto bail;
1073 }
1074 /*
1075 * If this request is a RDMA read or atomic, and the ACK is
1076 * for a later operation, this ACK NAKs the RDMA read or
1077 * atomic. In other words, only a RDMA_READ_LAST or ONLY
1078 * can ACK a RDMA read and likewise for atomic ops. Note
1079 * that the NAK case can only happen if relaxed ordering is
1080 * used and requests are sent after an RDMA read or atomic
1081 * is sent but before the response is received.
1082 */
1083 if ((wqe->wr.opcode == IB_WR_RDMA_READ &&
1084 (opcode != OP(RDMA_READ_RESPONSE_LAST) || diff != 0)) ||
1085 ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1086 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) &&
1087 (opcode != OP(ATOMIC_ACKNOWLEDGE) || diff != 0))) {
1088 /* Retry this request. */
1089 if (!(qp->r_flags & RVT_R_RDMAR_SEQ)) {
1090 qp->r_flags |= RVT_R_RDMAR_SEQ;
1091 qib_restart_rc(qp, qp->s_last_psn + 1, 0);
1092 if (list_empty(&qp->rspwait)) {
1093 qp->r_flags |= RVT_R_RSP_SEND;
1094 rvt_get_qp(qp);
1095 list_add_tail(&qp->rspwait,
1096 &rcd->qp_wait_list);
1097 }
1098 }
1099 /*
1100 * No need to process the ACK/NAK since we are
1101 * restarting an earlier request.
1102 */
1103 goto bail;
1104 }
1105 if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1106 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) {
1107 u64 *vaddr = wqe->sg_list[0].vaddr;
1108 *vaddr = val;
1109 }
1110 if (qp->s_num_rd_atomic &&
1111 (wqe->wr.opcode == IB_WR_RDMA_READ ||
1112 wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1113 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)) {
1114 qp->s_num_rd_atomic--;
1115 /* Restart sending task if fence is complete */
1116 if ((qp->s_flags & RVT_S_WAIT_FENCE) &&
1117 !qp->s_num_rd_atomic) {
1118 qp->s_flags &= ~(RVT_S_WAIT_FENCE |
1119 RVT_S_WAIT_ACK);
1120 qib_schedule_send(qp);
1121 } else if (qp->s_flags & RVT_S_WAIT_RDMAR) {
1122 qp->s_flags &= ~(RVT_S_WAIT_RDMAR |
1123 RVT_S_WAIT_ACK);
1124 qib_schedule_send(qp);
1125 }
1126 }
1127 wqe = do_rc_completion(qp, wqe, ibp);
1128 if (qp->s_acked == qp->s_tail)
1129 break;
1130 }
1131
1132 switch (aeth >> IB_AETH_NAK_SHIFT) {
1133 case 0: /* ACK */
1134 this_cpu_inc(*ibp->rvp.rc_acks);
1135 if (qp->s_acked != qp->s_tail) {
1136 /*
1137 * We are expecting more ACKs so
1138 * reset the retransmit timer.
1139 */
1140 rvt_mod_retry_timer(qp);
1141 /*
1142 * We can stop resending the earlier packets and
1143 * continue with the next packet the receiver wants.
1144 */
1145 if (qib_cmp24(qp->s_psn, psn) <= 0)
1146 reset_psn(qp, psn + 1);
1147 } else {
1148 /* No more acks - kill all timers */
1149 rvt_stop_rc_timers(qp);
1150 if (qib_cmp24(qp->s_psn, psn) <= 0) {
1151 qp->s_state = OP(SEND_LAST);
1152 qp->s_psn = psn + 1;
1153 }
1154 }
1155 if (qp->s_flags & RVT_S_WAIT_ACK) {
1156 qp->s_flags &= ~RVT_S_WAIT_ACK;
1157 qib_schedule_send(qp);
1158 }
1159 rvt_get_credit(qp, aeth);
1160 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
1161 qp->s_retry = qp->s_retry_cnt;
1162 update_last_psn(qp, psn);
1163 return 1;
1164
1165 case 1: /* RNR NAK */
1166 ibp->rvp.n_rnr_naks++;
1167 if (qp->s_acked == qp->s_tail)
1168 goto bail;
1169 if (qp->s_flags & RVT_S_WAIT_RNR)
1170 goto bail;
1171 if (qp->s_rnr_retry == 0) {
1172 status = IB_WC_RNR_RETRY_EXC_ERR;
1173 goto class_b;
1174 }
1175 if (qp->s_rnr_retry_cnt < 7)
1176 qp->s_rnr_retry--;
1177
1178 /* The last valid PSN is the previous PSN. */
1179 update_last_psn(qp, psn - 1);
1180
1181 ibp->rvp.n_rc_resends += (qp->s_psn - psn) & QIB_PSN_MASK;
1182
1183 reset_psn(qp, psn);
1184
1185 qp->s_flags &= ~(RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_ACK);
1186 rvt_stop_rc_timers(qp);
1187 rvt_add_rnr_timer(qp, aeth);
1188 return 0;
1189
1190 case 3: /* NAK */
1191 if (qp->s_acked == qp->s_tail)
1192 goto bail;
1193 /* The last valid PSN is the previous PSN. */
1194 update_last_psn(qp, psn - 1);
1195 switch ((aeth >> IB_AETH_CREDIT_SHIFT) &
1196 IB_AETH_CREDIT_MASK) {
1197 case 0: /* PSN sequence error */
1198 ibp->rvp.n_seq_naks++;
1199 /*
1200 * Back up to the responder's expected PSN.
1201 * Note that we might get a NAK in the middle of an
1202 * RDMA READ response which terminates the RDMA
1203 * READ.
1204 */
1205 qib_restart_rc(qp, psn, 0);
1206 qib_schedule_send(qp);
1207 break;
1208
1209 case 1: /* Invalid Request */
1210 status = IB_WC_REM_INV_REQ_ERR;
1211 ibp->rvp.n_other_naks++;
1212 goto class_b;
1213
1214 case 2: /* Remote Access Error */
1215 status = IB_WC_REM_ACCESS_ERR;
1216 ibp->rvp.n_other_naks++;
1217 goto class_b;
1218
1219 case 3: /* Remote Operation Error */
1220 status = IB_WC_REM_OP_ERR;
1221 ibp->rvp.n_other_naks++;
1222 class_b:
1223 if (qp->s_last == qp->s_acked) {
1224 qib_send_complete(qp, wqe, status);
1225 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1226 }
1227 break;
1228
1229 default:
1230 /* Ignore other reserved NAK error codes */
1231 goto reserved;
1232 }
1233 qp->s_retry = qp->s_retry_cnt;
1234 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
1235 goto bail;
1236
1237 default: /* 2: reserved */
1238 reserved:
1239 /* Ignore reserved NAK codes. */
1240 goto bail;
1241 }
1242
1243 bail:
1244 rvt_stop_rc_timers(qp);
1245 return ret;
1246 }
1247
1248 /*
1249 * We have seen an out of sequence RDMA read middle or last packet.
1250 * This ACKs SENDs and RDMA writes up to the first RDMA read or atomic SWQE.
1251 */
1252 static void rdma_seq_err(struct rvt_qp *qp, struct qib_ibport *ibp, u32 psn,
1253 struct qib_ctxtdata *rcd)
1254 {
1255 struct rvt_swqe *wqe;
1256
1257 /* Remove QP from retry timer */
1258 rvt_stop_rc_timers(qp);
1259
1260 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1261
1262 while (qib_cmp24(psn, wqe->lpsn) > 0) {
1263 if (wqe->wr.opcode == IB_WR_RDMA_READ ||
1264 wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1265 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)
1266 break;
1267 wqe = do_rc_completion(qp, wqe, ibp);
1268 }
1269
1270 ibp->rvp.n_rdma_seq++;
1271 qp->r_flags |= RVT_R_RDMAR_SEQ;
1272 qib_restart_rc(qp, qp->s_last_psn + 1, 0);
1273 if (list_empty(&qp->rspwait)) {
1274 qp->r_flags |= RVT_R_RSP_SEND;
1275 rvt_get_qp(qp);
1276 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
1277 }
1278 }
1279
1280 /**
1281 * qib_rc_rcv_resp - process an incoming RC response packet
1282 * @ibp: the port this packet came in on
1283 * @ohdr: the other headers for this packet
1284 * @data: the packet data
1285 * @tlen: the packet length
1286 * @qp: the QP for this packet
1287 * @opcode: the opcode for this packet
1288 * @psn: the packet sequence number for this packet
1289 * @hdrsize: the header length
1290 * @pmtu: the path MTU
1291 *
1292 * This is called from qib_rc_rcv() to process an incoming RC response
1293 * packet for the given QP.
1294 * Called at interrupt level.
1295 */
1296 static void qib_rc_rcv_resp(struct qib_ibport *ibp,
1297 struct ib_other_headers *ohdr,
1298 void *data, u32 tlen,
1299 struct rvt_qp *qp,
1300 u32 opcode,
1301 u32 psn, u32 hdrsize, u32 pmtu,
1302 struct qib_ctxtdata *rcd)
1303 {
1304 struct rvt_swqe *wqe;
1305 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
1306 enum ib_wc_status status;
1307 unsigned long flags;
1308 int diff;
1309 u32 pad;
1310 u32 aeth;
1311 u64 val;
1312
1313 if (opcode != OP(RDMA_READ_RESPONSE_MIDDLE)) {
1314 /*
1315 * If ACK'd PSN on SDMA busy list try to make progress to
1316 * reclaim SDMA credits.
1317 */
1318 if ((qib_cmp24(psn, qp->s_sending_psn) >= 0) &&
1319 (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)) {
1320
1321 /*
1322 * If send tasklet not running attempt to progress
1323 * SDMA queue.
1324 */
1325 if (!(qp->s_flags & RVT_S_BUSY)) {
1326 /* Acquire SDMA Lock */
1327 spin_lock_irqsave(&ppd->sdma_lock, flags);
1328 /* Invoke sdma make progress */
1329 qib_sdma_make_progress(ppd);
1330 /* Release SDMA Lock */
1331 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1332 }
1333 }
1334 }
1335
1336 spin_lock_irqsave(&qp->s_lock, flags);
1337 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
1338 goto ack_done;
1339
1340 /* Ignore invalid responses. */
1341 if (qib_cmp24(psn, READ_ONCE(qp->s_next_psn)) >= 0)
1342 goto ack_done;
1343
1344 /* Ignore duplicate responses. */
1345 diff = qib_cmp24(psn, qp->s_last_psn);
1346 if (unlikely(diff <= 0)) {
1347 /* Update credits for "ghost" ACKs */
1348 if (diff == 0 && opcode == OP(ACKNOWLEDGE)) {
1349 aeth = be32_to_cpu(ohdr->u.aeth);
1350 if ((aeth >> IB_AETH_NAK_SHIFT) == 0)
1351 rvt_get_credit(qp, aeth);
1352 }
1353 goto ack_done;
1354 }
1355
1356 /*
1357 * Skip everything other than the PSN we expect, if we are waiting
1358 * for a reply to a restarted RDMA read or atomic op.
1359 */
1360 if (qp->r_flags & RVT_R_RDMAR_SEQ) {
1361 if (qib_cmp24(psn, qp->s_last_psn + 1) != 0)
1362 goto ack_done;
1363 qp->r_flags &= ~RVT_R_RDMAR_SEQ;
1364 }
1365
1366 if (unlikely(qp->s_acked == qp->s_tail))
1367 goto ack_done;
1368 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1369 status = IB_WC_SUCCESS;
1370
1371 switch (opcode) {
1372 case OP(ACKNOWLEDGE):
1373 case OP(ATOMIC_ACKNOWLEDGE):
1374 case OP(RDMA_READ_RESPONSE_FIRST):
1375 aeth = be32_to_cpu(ohdr->u.aeth);
1376 if (opcode == OP(ATOMIC_ACKNOWLEDGE))
1377 val = ib_u64_get(&ohdr->u.at.atomic_ack_eth);
1378 else
1379 val = 0;
1380 if (!do_rc_ack(qp, aeth, psn, opcode, val, rcd) ||
1381 opcode != OP(RDMA_READ_RESPONSE_FIRST))
1382 goto ack_done;
1383 hdrsize += 4;
1384 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1385 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
1386 goto ack_op_err;
1387 /*
1388 * If this is a response to a resent RDMA read, we
1389 * have to be careful to copy the data to the right
1390 * location.
1391 */
1392 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
1393 wqe, psn, pmtu);
1394 goto read_middle;
1395
1396 case OP(RDMA_READ_RESPONSE_MIDDLE):
1397 /* no AETH, no ACK */
1398 if (unlikely(qib_cmp24(psn, qp->s_last_psn + 1)))
1399 goto ack_seq_err;
1400 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
1401 goto ack_op_err;
1402 read_middle:
1403 if (unlikely(tlen != (hdrsize + pmtu + 4)))
1404 goto ack_len_err;
1405 if (unlikely(pmtu >= qp->s_rdma_read_len))
1406 goto ack_len_err;
1407
1408 /*
1409 * We got a response so update the timeout.
1410 * 4.096 usec. * (1 << qp->timeout)
1411 */
1412 rvt_mod_retry_timer(qp);
1413 if (qp->s_flags & RVT_S_WAIT_ACK) {
1414 qp->s_flags &= ~RVT_S_WAIT_ACK;
1415 qib_schedule_send(qp);
1416 }
1417
1418 if (opcode == OP(RDMA_READ_RESPONSE_MIDDLE))
1419 qp->s_retry = qp->s_retry_cnt;
1420
1421 /*
1422 * Update the RDMA receive state but do the copy w/o
1423 * holding the locks and blocking interrupts.
1424 */
1425 qp->s_rdma_read_len -= pmtu;
1426 update_last_psn(qp, psn);
1427 spin_unlock_irqrestore(&qp->s_lock, flags);
1428 qib_copy_sge(&qp->s_rdma_read_sge, data, pmtu, 0);
1429 goto bail;
1430
1431 case OP(RDMA_READ_RESPONSE_ONLY):
1432 aeth = be32_to_cpu(ohdr->u.aeth);
1433 if (!do_rc_ack(qp, aeth, psn, opcode, 0, rcd))
1434 goto ack_done;
1435 /* Get the number of bytes the message was padded by. */
1436 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
1437 /*
1438 * Check that the data size is >= 0 && <= pmtu.
1439 * Remember to account for the AETH header (4) and
1440 * ICRC (4).
1441 */
1442 if (unlikely(tlen < (hdrsize + pad + 8)))
1443 goto ack_len_err;
1444 /*
1445 * If this is a response to a resent RDMA read, we
1446 * have to be careful to copy the data to the right
1447 * location.
1448 */
1449 wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1450 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
1451 wqe, psn, pmtu);
1452 goto read_last;
1453
1454 case OP(RDMA_READ_RESPONSE_LAST):
1455 /* ACKs READ req. */
1456 if (unlikely(qib_cmp24(psn, qp->s_last_psn + 1)))
1457 goto ack_seq_err;
1458 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
1459 goto ack_op_err;
1460 /* Get the number of bytes the message was padded by. */
1461 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
1462 /*
1463 * Check that the data size is >= 1 && <= pmtu.
1464 * Remember to account for the AETH header (4) and
1465 * ICRC (4).
1466 */
1467 if (unlikely(tlen <= (hdrsize + pad + 8)))
1468 goto ack_len_err;
1469 read_last:
1470 tlen -= hdrsize + pad + 8;
1471 if (unlikely(tlen != qp->s_rdma_read_len))
1472 goto ack_len_err;
1473 aeth = be32_to_cpu(ohdr->u.aeth);
1474 qib_copy_sge(&qp->s_rdma_read_sge, data, tlen, 0);
1475 WARN_ON(qp->s_rdma_read_sge.num_sge);
1476 (void) do_rc_ack(qp, aeth, psn,
1477 OP(RDMA_READ_RESPONSE_LAST), 0, rcd);
1478 goto ack_done;
1479 }
1480
1481 ack_op_err:
1482 status = IB_WC_LOC_QP_OP_ERR;
1483 goto ack_err;
1484
1485 ack_seq_err:
1486 rdma_seq_err(qp, ibp, psn, rcd);
1487 goto ack_done;
1488
1489 ack_len_err:
1490 status = IB_WC_LOC_LEN_ERR;
1491 ack_err:
1492 if (qp->s_last == qp->s_acked) {
1493 qib_send_complete(qp, wqe, status);
1494 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1495 }
1496 ack_done:
1497 spin_unlock_irqrestore(&qp->s_lock, flags);
1498 bail:
1499 return;
1500 }
1501
1502 /**
1503 * qib_rc_rcv_error - process an incoming duplicate or error RC packet
1504 * @ohdr: the other headers for this packet
1505 * @data: the packet data
1506 * @qp: the QP for this packet
1507 * @opcode: the opcode for this packet
1508 * @psn: the packet sequence number for this packet
1509 * @diff: the difference between the PSN and the expected PSN
1510 *
1511 * This is called from qib_rc_rcv() to process an unexpected
1512 * incoming RC packet for the given QP.
1513 * Called at interrupt level.
1514 * Return 1 if no more processing is needed; otherwise return 0 to
1515 * schedule a response to be sent.
1516 */
1517 static int qib_rc_rcv_error(struct ib_other_headers *ohdr,
1518 void *data,
1519 struct rvt_qp *qp,
1520 u32 opcode,
1521 u32 psn,
1522 int diff,
1523 struct qib_ctxtdata *rcd)
1524 {
1525 struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
1526 struct rvt_ack_entry *e;
1527 unsigned long flags;
1528 u8 i, prev;
1529 int old_req;
1530
1531 if (diff > 0) {
1532 /*
1533 * Packet sequence error.
1534 * A NAK will ACK earlier sends and RDMA writes.
1535 * Don't queue the NAK if we already sent one.
1536 */
1537 if (!qp->r_nak_state) {
1538 ibp->rvp.n_rc_seqnak++;
1539 qp->r_nak_state = IB_NAK_PSN_ERROR;
1540 /* Use the expected PSN. */
1541 qp->r_ack_psn = qp->r_psn;
1542 /*
1543 * Wait to send the sequence NAK until all packets
1544 * in the receive queue have been processed.
1545 * Otherwise, we end up propagating congestion.
1546 */
1547 if (list_empty(&qp->rspwait)) {
1548 qp->r_flags |= RVT_R_RSP_NAK;
1549 rvt_get_qp(qp);
1550 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
1551 }
1552 }
1553 goto done;
1554 }
1555
1556 /*
1557 * Handle a duplicate request. Don't re-execute SEND, RDMA
1558 * write or atomic op. Don't NAK errors, just silently drop
1559 * the duplicate request. Note that r_sge, r_len, and
1560 * r_rcv_len may be in use so don't modify them.
1561 *
1562 * We are supposed to ACK the earliest duplicate PSN but we
1563 * can coalesce an outstanding duplicate ACK. We have to
1564 * send the earliest so that RDMA reads can be restarted at
1565 * the requester's expected PSN.
1566 *
1567 * First, find where this duplicate PSN falls within the
1568 * ACKs previously sent.
1569 * old_req is true if there is an older response that is scheduled
1570 * to be sent before sending this one.
1571 */
1572 e = NULL;
1573 old_req = 1;
1574 ibp->rvp.n_rc_dupreq++;
1575
1576 spin_lock_irqsave(&qp->s_lock, flags);
1577
1578 for (i = qp->r_head_ack_queue; ; i = prev) {
1579 if (i == qp->s_tail_ack_queue)
1580 old_req = 0;
1581 if (i)
1582 prev = i - 1;
1583 else
1584 prev = QIB_MAX_RDMA_ATOMIC;
1585 if (prev == qp->r_head_ack_queue) {
1586 e = NULL;
1587 break;
1588 }
1589 e = &qp->s_ack_queue[prev];
1590 if (!e->opcode) {
1591 e = NULL;
1592 break;
1593 }
1594 if (qib_cmp24(psn, e->psn) >= 0) {
1595 if (prev == qp->s_tail_ack_queue &&
1596 qib_cmp24(psn, e->lpsn) <= 0)
1597 old_req = 0;
1598 break;
1599 }
1600 }
1601 switch (opcode) {
1602 case OP(RDMA_READ_REQUEST): {
1603 struct ib_reth *reth;
1604 u32 offset;
1605 u32 len;
1606
1607 /*
1608 * If we didn't find the RDMA read request in the ack queue,
1609 * we can ignore this request.
1610 */
1611 if (!e || e->opcode != OP(RDMA_READ_REQUEST))
1612 goto unlock_done;
1613 /* RETH comes after BTH */
1614 reth = &ohdr->u.rc.reth;
1615 /*
1616 * Address range must be a subset of the original
1617 * request and start on pmtu boundaries.
1618 * We reuse the old ack_queue slot since the requester
1619 * should not back up and request an earlier PSN for the
1620 * same request.
1621 */
1622 offset = ((psn - e->psn) & QIB_PSN_MASK) *
1623 qp->pmtu;
1624 len = be32_to_cpu(reth->length);
1625 if (unlikely(offset + len != e->rdma_sge.sge_length))
1626 goto unlock_done;
1627 if (e->rdma_sge.mr) {
1628 rvt_put_mr(e->rdma_sge.mr);
1629 e->rdma_sge.mr = NULL;
1630 }
1631 if (len != 0) {
1632 u32 rkey = be32_to_cpu(reth->rkey);
1633 u64 vaddr = be64_to_cpu(reth->vaddr);
1634 int ok;
1635
1636 ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey,
1637 IB_ACCESS_REMOTE_READ);
1638 if (unlikely(!ok))
1639 goto unlock_done;
1640 } else {
1641 e->rdma_sge.vaddr = NULL;
1642 e->rdma_sge.length = 0;
1643 e->rdma_sge.sge_length = 0;
1644 }
1645 e->psn = psn;
1646 if (old_req)
1647 goto unlock_done;
1648 qp->s_tail_ack_queue = prev;
1649 break;
1650 }
1651
1652 case OP(COMPARE_SWAP):
1653 case OP(FETCH_ADD): {
1654 /*
1655 * If we didn't find the atomic request in the ack queue
1656 * or the send tasklet is already backed up to send an
1657 * earlier entry, we can ignore this request.
1658 */
1659 if (!e || e->opcode != (u8) opcode || old_req)
1660 goto unlock_done;
1661 qp->s_tail_ack_queue = prev;
1662 break;
1663 }
1664
1665 default:
1666 /*
1667 * Ignore this operation if it doesn't request an ACK
1668 * or an earlier RDMA read or atomic is going to be resent.
1669 */
1670 if (!(psn & IB_BTH_REQ_ACK) || old_req)
1671 goto unlock_done;
1672 /*
1673 * Resend the most recent ACK if this request is
1674 * after all the previous RDMA reads and atomics.
1675 */
1676 if (i == qp->r_head_ack_queue) {
1677 spin_unlock_irqrestore(&qp->s_lock, flags);
1678 qp->r_nak_state = 0;
1679 qp->r_ack_psn = qp->r_psn - 1;
1680 goto send_ack;
1681 }
1682 /*
1683 * Try to send a simple ACK to work around a Mellanox bug
1684 * which doesn't accept a RDMA read response or atomic
1685 * response as an ACK for earlier SENDs or RDMA writes.
1686 */
1687 if (!(qp->s_flags & RVT_S_RESP_PENDING)) {
1688 spin_unlock_irqrestore(&qp->s_lock, flags);
1689 qp->r_nak_state = 0;
1690 qp->r_ack_psn = qp->s_ack_queue[i].psn - 1;
1691 goto send_ack;
1692 }
1693 /*
1694 * Resend the RDMA read or atomic op which
1695 * ACKs this duplicate request.
1696 */
1697 qp->s_tail_ack_queue = i;
1698 break;
1699 }
1700 qp->s_ack_state = OP(ACKNOWLEDGE);
1701 qp->s_flags |= RVT_S_RESP_PENDING;
1702 qp->r_nak_state = 0;
1703 qib_schedule_send(qp);
1704
1705 unlock_done:
1706 spin_unlock_irqrestore(&qp->s_lock, flags);
1707 done:
1708 return 1;
1709
1710 send_ack:
1711 return 0;
1712 }
1713
1714 static inline void qib_update_ack_queue(struct rvt_qp *qp, unsigned n)
1715 {
1716 unsigned next;
1717
1718 next = n + 1;
1719 if (next > QIB_MAX_RDMA_ATOMIC)
1720 next = 0;
1721 qp->s_tail_ack_queue = next;
1722 qp->s_ack_state = OP(ACKNOWLEDGE);
1723 }
1724
1725 /**
1726 * qib_rc_rcv - process an incoming RC packet
1727 * @rcd: the context pointer
1728 * @hdr: the header of this packet
1729 * @has_grh: true if the header has a GRH
1730 * @data: the packet data
1731 * @tlen: the packet length
1732 * @qp: the QP for this packet
1733 *
1734 * This is called from qib_qp_rcv() to process an incoming RC packet
1735 * for the given QP.
1736 * Called at interrupt level.
1737 */
1738 void qib_rc_rcv(struct qib_ctxtdata *rcd, struct ib_header *hdr,
1739 int has_grh, void *data, u32 tlen, struct rvt_qp *qp)
1740 {
1741 struct qib_ibport *ibp = &rcd->ppd->ibport_data;
1742 struct ib_other_headers *ohdr;
1743 u32 opcode;
1744 u32 hdrsize;
1745 u32 psn;
1746 u32 pad;
1747 struct ib_wc wc;
1748 u32 pmtu = qp->pmtu;
1749 int diff;
1750 struct ib_reth *reth;
1751 unsigned long flags;
1752 int ret;
1753
1754 /* Check for GRH */
1755 if (!has_grh) {
1756 ohdr = &hdr->u.oth;
1757 hdrsize = 8 + 12; /* LRH + BTH */
1758 } else {
1759 ohdr = &hdr->u.l.oth;
1760 hdrsize = 8 + 40 + 12; /* LRH + GRH + BTH */
1761 }
1762
1763 opcode = be32_to_cpu(ohdr->bth[0]);
1764 if (qib_ruc_check_hdr(ibp, hdr, has_grh, qp, opcode))
1765 return;
1766
1767 psn = be32_to_cpu(ohdr->bth[2]);
1768 opcode >>= 24;
1769
1770 /*
1771 * Process responses (ACKs) before anything else. Note that the
1772 * packet sequence number will be for something in the send work
1773 * queue rather than the expected receive packet sequence number.
1774 * In other words, this QP is the requester.
1775 */
1776 if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1777 opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
1778 qib_rc_rcv_resp(ibp, ohdr, data, tlen, qp, opcode, psn,
1779 hdrsize, pmtu, rcd);
1780 return;
1781 }
1782
1783 /* Compute 24 bits worth of difference. */
1784 diff = qib_cmp24(psn, qp->r_psn);
1785 if (unlikely(diff)) {
1786 if (qib_rc_rcv_error(ohdr, data, qp, opcode, psn, diff, rcd))
1787 return;
1788 goto send_ack;
1789 }
1790
1791 /* Check for opcode sequence errors. */
1792 switch (qp->r_state) {
1793 case OP(SEND_FIRST):
1794 case OP(SEND_MIDDLE):
1795 if (opcode == OP(SEND_MIDDLE) ||
1796 opcode == OP(SEND_LAST) ||
1797 opcode == OP(SEND_LAST_WITH_IMMEDIATE))
1798 break;
1799 goto nack_inv;
1800
1801 case OP(RDMA_WRITE_FIRST):
1802 case OP(RDMA_WRITE_MIDDLE):
1803 if (opcode == OP(RDMA_WRITE_MIDDLE) ||
1804 opcode == OP(RDMA_WRITE_LAST) ||
1805 opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
1806 break;
1807 goto nack_inv;
1808
1809 default:
1810 if (opcode == OP(SEND_MIDDLE) ||
1811 opcode == OP(SEND_LAST) ||
1812 opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
1813 opcode == OP(RDMA_WRITE_MIDDLE) ||
1814 opcode == OP(RDMA_WRITE_LAST) ||
1815 opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
1816 goto nack_inv;
1817 /*
1818 * Note that it is up to the requester to not send a new
1819 * RDMA read or atomic operation before receiving an ACK
1820 * for the previous operation.
1821 */
1822 break;
1823 }
1824
1825 if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST))
1826 rvt_comm_est(qp);
1827
1828 /* OK, process the packet. */
1829 switch (opcode) {
1830 case OP(SEND_FIRST):
1831 ret = qib_get_rwqe(qp, 0);
1832 if (ret < 0)
1833 goto nack_op_err;
1834 if (!ret)
1835 goto rnr_nak;
1836 qp->r_rcv_len = 0;
1837 /* FALLTHROUGH */
1838 case OP(SEND_MIDDLE):
1839 case OP(RDMA_WRITE_MIDDLE):
1840 send_middle:
1841 /* Check for invalid length PMTU or posted rwqe len. */
1842 if (unlikely(tlen != (hdrsize + pmtu + 4)))
1843 goto nack_inv;
1844 qp->r_rcv_len += pmtu;
1845 if (unlikely(qp->r_rcv_len > qp->r_len))
1846 goto nack_inv;
1847 qib_copy_sge(&qp->r_sge, data, pmtu, 1);
1848 break;
1849
1850 case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
1851 /* consume RWQE */
1852 ret = qib_get_rwqe(qp, 1);
1853 if (ret < 0)
1854 goto nack_op_err;
1855 if (!ret)
1856 goto rnr_nak;
1857 goto send_last_imm;
1858
1859 case OP(SEND_ONLY):
1860 case OP(SEND_ONLY_WITH_IMMEDIATE):
1861 ret = qib_get_rwqe(qp, 0);
1862 if (ret < 0)
1863 goto nack_op_err;
1864 if (!ret)
1865 goto rnr_nak;
1866 qp->r_rcv_len = 0;
1867 if (opcode == OP(SEND_ONLY))
1868 goto no_immediate_data;
1869 /* fall through -- for SEND_ONLY_WITH_IMMEDIATE */
1870 case OP(SEND_LAST_WITH_IMMEDIATE):
1871 send_last_imm:
1872 wc.ex.imm_data = ohdr->u.imm_data;
1873 hdrsize += 4;
1874 wc.wc_flags = IB_WC_WITH_IMM;
1875 goto send_last;
1876 case OP(SEND_LAST):
1877 case OP(RDMA_WRITE_LAST):
1878 no_immediate_data:
1879 wc.wc_flags = 0;
1880 wc.ex.imm_data = 0;
1881 send_last:
1882 /* Get the number of bytes the message was padded by. */
1883 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
1884 /* Check for invalid length. */
1885 /* XXX LAST len should be >= 1 */
1886 if (unlikely(tlen < (hdrsize + pad + 4)))
1887 goto nack_inv;
1888 /* Don't count the CRC. */
1889 tlen -= (hdrsize + pad + 4);
1890 wc.byte_len = tlen + qp->r_rcv_len;
1891 if (unlikely(wc.byte_len > qp->r_len))
1892 goto nack_inv;
1893 qib_copy_sge(&qp->r_sge, data, tlen, 1);
1894 rvt_put_ss(&qp->r_sge);
1895 qp->r_msn++;
1896 if (!test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
1897 break;
1898 wc.wr_id = qp->r_wr_id;
1899 wc.status = IB_WC_SUCCESS;
1900 if (opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE) ||
1901 opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
1902 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
1903 else
1904 wc.opcode = IB_WC_RECV;
1905 wc.qp = &qp->ibqp;
1906 wc.src_qp = qp->remote_qpn;
1907 wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr);
1908 wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
1909 /* zero fields that are N/A */
1910 wc.vendor_err = 0;
1911 wc.pkey_index = 0;
1912 wc.dlid_path_bits = 0;
1913 wc.port_num = 0;
1914 /* Signal completion event if the solicited bit is set. */
1915 rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
1916 ib_bth_is_solicited(ohdr));
1917 break;
1918
1919 case OP(RDMA_WRITE_FIRST):
1920 case OP(RDMA_WRITE_ONLY):
1921 case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
1922 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
1923 goto nack_inv;
1924 /* consume RWQE */
1925 reth = &ohdr->u.rc.reth;
1926 hdrsize += sizeof(*reth);
1927 qp->r_len = be32_to_cpu(reth->length);
1928 qp->r_rcv_len = 0;
1929 qp->r_sge.sg_list = NULL;
1930 if (qp->r_len != 0) {
1931 u32 rkey = be32_to_cpu(reth->rkey);
1932 u64 vaddr = be64_to_cpu(reth->vaddr);
1933 int ok;
1934
1935 /* Check rkey & NAK */
1936 ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len, vaddr,
1937 rkey, IB_ACCESS_REMOTE_WRITE);
1938 if (unlikely(!ok))
1939 goto nack_acc;
1940 qp->r_sge.num_sge = 1;
1941 } else {
1942 qp->r_sge.num_sge = 0;
1943 qp->r_sge.sge.mr = NULL;
1944 qp->r_sge.sge.vaddr = NULL;
1945 qp->r_sge.sge.length = 0;
1946 qp->r_sge.sge.sge_length = 0;
1947 }
1948 if (opcode == OP(RDMA_WRITE_FIRST))
1949 goto send_middle;
1950 else if (opcode == OP(RDMA_WRITE_ONLY))
1951 goto no_immediate_data;
1952 ret = qib_get_rwqe(qp, 1);
1953 if (ret < 0)
1954 goto nack_op_err;
1955 if (!ret) {
1956 rvt_put_ss(&qp->r_sge);
1957 goto rnr_nak;
1958 }
1959 wc.ex.imm_data = ohdr->u.rc.imm_data;
1960 hdrsize += 4;
1961 wc.wc_flags = IB_WC_WITH_IMM;
1962 goto send_last;
1963
1964 case OP(RDMA_READ_REQUEST): {
1965 struct rvt_ack_entry *e;
1966 u32 len;
1967 u8 next;
1968
1969 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
1970 goto nack_inv;
1971 next = qp->r_head_ack_queue + 1;
1972 /* s_ack_queue is size QIB_MAX_RDMA_ATOMIC+1 so use > not >= */
1973 if (next > QIB_MAX_RDMA_ATOMIC)
1974 next = 0;
1975 spin_lock_irqsave(&qp->s_lock, flags);
1976 if (unlikely(next == qp->s_tail_ack_queue)) {
1977 if (!qp->s_ack_queue[next].sent)
1978 goto nack_inv_unlck;
1979 qib_update_ack_queue(qp, next);
1980 }
1981 e = &qp->s_ack_queue[qp->r_head_ack_queue];
1982 if (e->opcode == OP(RDMA_READ_REQUEST) && e->rdma_sge.mr) {
1983 rvt_put_mr(e->rdma_sge.mr);
1984 e->rdma_sge.mr = NULL;
1985 }
1986 reth = &ohdr->u.rc.reth;
1987 len = be32_to_cpu(reth->length);
1988 if (len) {
1989 u32 rkey = be32_to_cpu(reth->rkey);
1990 u64 vaddr = be64_to_cpu(reth->vaddr);
1991 int ok;
1992
1993 /* Check rkey & NAK */
1994 ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr,
1995 rkey, IB_ACCESS_REMOTE_READ);
1996 if (unlikely(!ok))
1997 goto nack_acc_unlck;
1998 /*
1999 * Update the next expected PSN. We add 1 later
2000 * below, so only add the remainder here.
2001 */
2002 qp->r_psn += rvt_div_mtu(qp, len - 1);
2003 } else {
2004 e->rdma_sge.mr = NULL;
2005 e->rdma_sge.vaddr = NULL;
2006 e->rdma_sge.length = 0;
2007 e->rdma_sge.sge_length = 0;
2008 }
2009 e->opcode = opcode;
2010 e->sent = 0;
2011 e->psn = psn;
2012 e->lpsn = qp->r_psn;
2013 /*
2014 * We need to increment the MSN here instead of when we
2015 * finish sending the result since a duplicate request would
2016 * increment it more than once.
2017 */
2018 qp->r_msn++;
2019 qp->r_psn++;
2020 qp->r_state = opcode;
2021 qp->r_nak_state = 0;
2022 qp->r_head_ack_queue = next;
2023
2024 /* Schedule the send tasklet. */
2025 qp->s_flags |= RVT_S_RESP_PENDING;
2026 qib_schedule_send(qp);
2027
2028 goto sunlock;
2029 }
2030
2031 case OP(COMPARE_SWAP):
2032 case OP(FETCH_ADD): {
2033 struct ib_atomic_eth *ateth;
2034 struct rvt_ack_entry *e;
2035 u64 vaddr;
2036 atomic64_t *maddr;
2037 u64 sdata;
2038 u32 rkey;
2039 u8 next;
2040
2041 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
2042 goto nack_inv;
2043 next = qp->r_head_ack_queue + 1;
2044 if (next > QIB_MAX_RDMA_ATOMIC)
2045 next = 0;
2046 spin_lock_irqsave(&qp->s_lock, flags);
2047 if (unlikely(next == qp->s_tail_ack_queue)) {
2048 if (!qp->s_ack_queue[next].sent)
2049 goto nack_inv_unlck;
2050 qib_update_ack_queue(qp, next);
2051 }
2052 e = &qp->s_ack_queue[qp->r_head_ack_queue];
2053 if (e->opcode == OP(RDMA_READ_REQUEST) && e->rdma_sge.mr) {
2054 rvt_put_mr(e->rdma_sge.mr);
2055 e->rdma_sge.mr = NULL;
2056 }
2057 ateth = &ohdr->u.atomic_eth;
2058 vaddr = get_ib_ateth_vaddr(ateth);
2059 if (unlikely(vaddr & (sizeof(u64) - 1)))
2060 goto nack_inv_unlck;
2061 rkey = be32_to_cpu(ateth->rkey);
2062 /* Check rkey & NAK */
2063 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
2064 vaddr, rkey,
2065 IB_ACCESS_REMOTE_ATOMIC)))
2066 goto nack_acc_unlck;
2067 /* Perform atomic OP and save result. */
2068 maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
2069 sdata = get_ib_ateth_swap(ateth);
2070 e->atomic_data = (opcode == OP(FETCH_ADD)) ?
2071 (u64) atomic64_add_return(sdata, maddr) - sdata :
2072 (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
2073 get_ib_ateth_compare(ateth),
2074 sdata);
2075 rvt_put_mr(qp->r_sge.sge.mr);
2076 qp->r_sge.num_sge = 0;
2077 e->opcode = opcode;
2078 e->sent = 0;
2079 e->psn = psn;
2080 e->lpsn = psn;
2081 qp->r_msn++;
2082 qp->r_psn++;
2083 qp->r_state = opcode;
2084 qp->r_nak_state = 0;
2085 qp->r_head_ack_queue = next;
2086
2087 /* Schedule the send tasklet. */
2088 qp->s_flags |= RVT_S_RESP_PENDING;
2089 qib_schedule_send(qp);
2090
2091 goto sunlock;
2092 }
2093
2094 default:
2095 /* NAK unknown opcodes. */
2096 goto nack_inv;
2097 }
2098 qp->r_psn++;
2099 qp->r_state = opcode;
2100 qp->r_ack_psn = psn;
2101 qp->r_nak_state = 0;
2102 /* Send an ACK if requested or required. */
2103 if (psn & (1 << 31))
2104 goto send_ack;
2105 return;
2106
2107 rnr_nak:
2108 qp->r_nak_state = IB_RNR_NAK | qp->r_min_rnr_timer;
2109 qp->r_ack_psn = qp->r_psn;
2110 /* Queue RNR NAK for later */
2111 if (list_empty(&qp->rspwait)) {
2112 qp->r_flags |= RVT_R_RSP_NAK;
2113 rvt_get_qp(qp);
2114 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
2115 }
2116 return;
2117
2118 nack_op_err:
2119 rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
2120 qp->r_nak_state = IB_NAK_REMOTE_OPERATIONAL_ERROR;
2121 qp->r_ack_psn = qp->r_psn;
2122 /* Queue NAK for later */
2123 if (list_empty(&qp->rspwait)) {
2124 qp->r_flags |= RVT_R_RSP_NAK;
2125 rvt_get_qp(qp);
2126 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
2127 }
2128 return;
2129
2130 nack_inv_unlck:
2131 spin_unlock_irqrestore(&qp->s_lock, flags);
2132 nack_inv:
2133 rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
2134 qp->r_nak_state = IB_NAK_INVALID_REQUEST;
2135 qp->r_ack_psn = qp->r_psn;
2136 /* Queue NAK for later */
2137 if (list_empty(&qp->rspwait)) {
2138 qp->r_flags |= RVT_R_RSP_NAK;
2139 rvt_get_qp(qp);
2140 list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
2141 }
2142 return;
2143
2144 nack_acc_unlck:
2145 spin_unlock_irqrestore(&qp->s_lock, flags);
2146 nack_acc:
2147 rvt_rc_error(qp, IB_WC_LOC_PROT_ERR);
2148 qp->r_nak_state = IB_NAK_REMOTE_ACCESS_ERROR;
2149 qp->r_ack_psn = qp->r_psn;
2150 send_ack:
2151 qib_send_rc_ack(qp);
2152 return;
2153
2154 sunlock:
2155 spin_unlock_irqrestore(&qp->s_lock, flags);
2156 }
CRIS linux kernel tree