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[PATCH] IB/ipath: update copyrights and other strings to reflect new company name
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / infiniband / hw / ipath / ipath_rc.c
blob33b8c78fcdcc76fa23572b64e4e4aea542df9a8e
1 /*
2 * Copyright (c) 2006 QLogic, Inc. 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 "ipath_verbs.h"
35 #include "ips_common.h"
36
37 /* cut down ridiculously long IB macro names */
38 #define OP(x) IB_OPCODE_RC_##x
39
40 /**
41 * ipath_init_restart- initialize the qp->s_sge after a restart
42 * @qp: the QP who's SGE we're restarting
43 * @wqe: the work queue to initialize the QP's SGE from
44 *
45 * The QP s_lock should be held.
46 */
47 static void ipath_init_restart(struct ipath_qp *qp, struct ipath_swqe *wqe)
48 {
49 struct ipath_ibdev *dev;
50 u32 len;
51
52 len = ((qp->s_psn - wqe->psn) & IPS_PSN_MASK) *
53 ib_mtu_enum_to_int(qp->path_mtu);
54 qp->s_sge.sge = wqe->sg_list[0];
55 qp->s_sge.sg_list = wqe->sg_list + 1;
56 qp->s_sge.num_sge = wqe->wr.num_sge;
57 ipath_skip_sge(&qp->s_sge, len);
58 qp->s_len = wqe->length - len;
59 dev = to_idev(qp->ibqp.device);
60 spin_lock(&dev->pending_lock);
61 if (list_empty(&qp->timerwait))
62 list_add_tail(&qp->timerwait,
63 &dev->pending[dev->pending_index]);
64 spin_unlock(&dev->pending_lock);
65 }
66
67 /**
68 * ipath_make_rc_ack - construct a response packet (ACK, NAK, or RDMA read)
69 * @qp: a pointer to the QP
70 * @ohdr: a pointer to the IB header being constructed
71 * @pmtu: the path MTU
72 *
73 * Return bth0 if constructed; otherwise, return 0.
74 * Note the QP s_lock must be held.
75 */
76 static inline u32 ipath_make_rc_ack(struct ipath_qp *qp,
77 struct ipath_other_headers *ohdr,
78 u32 pmtu)
79 {
80 struct ipath_sge_state *ss;
81 u32 hwords;
82 u32 len;
83 u32 bth0;
84
85 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
86 hwords = 5;
87
88 /*
89 * Send a response. Note that we are in the responder's
90 * side of the QP context.
91 */
92 switch (qp->s_ack_state) {
93 case OP(RDMA_READ_REQUEST):
94 ss = &qp->s_rdma_sge;
95 len = qp->s_rdma_len;
96 if (len > pmtu) {
97 len = pmtu;
98 qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST);
99 }
100 else
101 qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY);
102 qp->s_rdma_len -= len;
103 bth0 = qp->s_ack_state << 24;
104 ohdr->u.aeth = ipath_compute_aeth(qp);
105 hwords++;
106 break;
107
108 case OP(RDMA_READ_RESPONSE_FIRST):
109 qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE);
110 /* FALLTHROUGH */
111 case OP(RDMA_READ_RESPONSE_MIDDLE):
112 ss = &qp->s_rdma_sge;
113 len = qp->s_rdma_len;
114 if (len > pmtu)
115 len = pmtu;
116 else {
117 ohdr->u.aeth = ipath_compute_aeth(qp);
118 hwords++;
119 qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
120 }
121 qp->s_rdma_len -= len;
122 bth0 = qp->s_ack_state << 24;
123 break;
124
125 case OP(RDMA_READ_RESPONSE_LAST):
126 case OP(RDMA_READ_RESPONSE_ONLY):
127 /*
128 * We have to prevent new requests from changing
129 * the r_sge state while a ipath_verbs_send()
130 * is in progress.
131 * Changing r_state allows the receiver
132 * to continue processing new packets.
133 * We do it here now instead of above so
134 * that we are sure the packet was sent before
135 * changing the state.
136 */
137 qp->r_state = OP(RDMA_READ_RESPONSE_LAST);
138 qp->s_ack_state = OP(ACKNOWLEDGE);
139 return 0;
140
141 case OP(COMPARE_SWAP):
142 case OP(FETCH_ADD):
143 ss = NULL;
144 len = 0;
145 qp->r_state = OP(SEND_LAST);
146 qp->s_ack_state = OP(ACKNOWLEDGE);
147 bth0 = IB_OPCODE_ATOMIC_ACKNOWLEDGE << 24;
148 ohdr->u.at.aeth = ipath_compute_aeth(qp);
149 ohdr->u.at.atomic_ack_eth = cpu_to_be64(qp->s_ack_atomic);
150 hwords += sizeof(ohdr->u.at) / 4;
151 break;
152
153 default:
154 /* Send a regular ACK. */
155 ss = NULL;
156 len = 0;
157 qp->s_ack_state = OP(ACKNOWLEDGE);
158 bth0 = qp->s_ack_state << 24;
159 ohdr->u.aeth = ipath_compute_aeth(qp);
160 hwords++;
161 }
162 qp->s_hdrwords = hwords;
163 qp->s_cur_sge = ss;
164 qp->s_cur_size = len;
165
166 return bth0;
167 }
168
169 /**
170 * ipath_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC)
171 * @qp: a pointer to the QP
172 * @ohdr: a pointer to the IB header being constructed
173 * @pmtu: the path MTU
174 * @bth0p: pointer to the BTH opcode word
175 * @bth2p: pointer to the BTH PSN word
176 *
177 * Return 1 if constructed; otherwise, return 0.
178 * Note the QP s_lock must be held.
179 */
180 static inline int ipath_make_rc_req(struct ipath_qp *qp,
181 struct ipath_other_headers *ohdr,
182 u32 pmtu, u32 *bth0p, u32 *bth2p)
183 {
184 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
185 struct ipath_sge_state *ss;
186 struct ipath_swqe *wqe;
187 u32 hwords;
188 u32 len;
189 u32 bth0;
190 u32 bth2;
191 char newreq;
192
193 if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK) ||
194 qp->s_rnr_timeout)
195 goto done;
196
197 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
198 hwords = 5;
199 bth0 = 0;
200
201 /* Send a request. */
202 wqe = get_swqe_ptr(qp, qp->s_cur);
203 switch (qp->s_state) {
204 default:
205 /*
206 * Resend an old request or start a new one.
207 *
208 * We keep track of the current SWQE so that
209 * we don't reset the "furthest progress" state
210 * if we need to back up.
211 */
212 newreq = 0;
213 if (qp->s_cur == qp->s_tail) {
214 /* Check if send work queue is empty. */
215 if (qp->s_tail == qp->s_head)
216 goto done;
217 qp->s_psn = wqe->psn = qp->s_next_psn;
218 newreq = 1;
219 }
220 /*
221 * Note that we have to be careful not to modify the
222 * original work request since we may need to resend
223 * it.
224 */
225 qp->s_sge.sge = wqe->sg_list[0];
226 qp->s_sge.sg_list = wqe->sg_list + 1;
227 qp->s_sge.num_sge = wqe->wr.num_sge;
228 qp->s_len = len = wqe->length;
229 ss = &qp->s_sge;
230 bth2 = 0;
231 switch (wqe->wr.opcode) {
232 case IB_WR_SEND:
233 case IB_WR_SEND_WITH_IMM:
234 /* If no credit, return. */
235 if (qp->s_lsn != (u32) -1 &&
236 ipath_cmp24(wqe->ssn, qp->s_lsn + 1) > 0)
237 goto done;
238 wqe->lpsn = wqe->psn;
239 if (len > pmtu) {
240 wqe->lpsn += (len - 1) / pmtu;
241 qp->s_state = OP(SEND_FIRST);
242 len = pmtu;
243 break;
244 }
245 if (wqe->wr.opcode == IB_WR_SEND)
246 qp->s_state = OP(SEND_ONLY);
247 else {
248 qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE);
249 /* Immediate data comes after the BTH */
250 ohdr->u.imm_data = wqe->wr.imm_data;
251 hwords += 1;
252 }
253 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
254 bth0 |= 1 << 23;
255 bth2 = 1 << 31; /* Request ACK. */
256 if (++qp->s_cur == qp->s_size)
257 qp->s_cur = 0;
258 break;
259
260 case IB_WR_RDMA_WRITE:
261 if (newreq)
262 qp->s_lsn++;
263 /* FALLTHROUGH */
264 case IB_WR_RDMA_WRITE_WITH_IMM:
265 /* If no credit, return. */
266 if (qp->s_lsn != (u32) -1 &&
267 ipath_cmp24(wqe->ssn, qp->s_lsn + 1) > 0)
268 goto done;
269 ohdr->u.rc.reth.vaddr =
270 cpu_to_be64(wqe->wr.wr.rdma.remote_addr);
271 ohdr->u.rc.reth.rkey =
272 cpu_to_be32(wqe->wr.wr.rdma.rkey);
273 ohdr->u.rc.reth.length = cpu_to_be32(len);
274 hwords += sizeof(struct ib_reth) / 4;
275 wqe->lpsn = wqe->psn;
276 if (len > pmtu) {
277 wqe->lpsn += (len - 1) / pmtu;
278 qp->s_state = OP(RDMA_WRITE_FIRST);
279 len = pmtu;
280 break;
281 }
282 if (wqe->wr.opcode == IB_WR_RDMA_WRITE)
283 qp->s_state = OP(RDMA_WRITE_ONLY);
284 else {
285 qp->s_state =
286 OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE);
287 /* Immediate data comes
288 * after RETH */
289 ohdr->u.rc.imm_data = wqe->wr.imm_data;
290 hwords += 1;
291 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
292 bth0 |= 1 << 23;
293 }
294 bth2 = 1 << 31; /* Request ACK. */
295 if (++qp->s_cur == qp->s_size)
296 qp->s_cur = 0;
297 break;
298
299 case IB_WR_RDMA_READ:
300 ohdr->u.rc.reth.vaddr =
301 cpu_to_be64(wqe->wr.wr.rdma.remote_addr);
302 ohdr->u.rc.reth.rkey =
303 cpu_to_be32(wqe->wr.wr.rdma.rkey);
304 ohdr->u.rc.reth.length = cpu_to_be32(len);
305 qp->s_state = OP(RDMA_READ_REQUEST);
306 hwords += sizeof(ohdr->u.rc.reth) / 4;
307 if (newreq) {
308 qp->s_lsn++;
309 /*
310 * Adjust s_next_psn to count the
311 * expected number of responses.
312 */
313 if (len > pmtu)
314 qp->s_next_psn += (len - 1) / pmtu;
315 wqe->lpsn = qp->s_next_psn++;
316 }
317 ss = NULL;
318 len = 0;
319 if (++qp->s_cur == qp->s_size)
320 qp->s_cur = 0;
321 break;
322
323 case IB_WR_ATOMIC_CMP_AND_SWP:
324 case IB_WR_ATOMIC_FETCH_AND_ADD:
325 if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP)
326 qp->s_state = OP(COMPARE_SWAP);
327 else
328 qp->s_state = OP(FETCH_ADD);
329 ohdr->u.atomic_eth.vaddr = cpu_to_be64(
330 wqe->wr.wr.atomic.remote_addr);
331 ohdr->u.atomic_eth.rkey = cpu_to_be32(
332 wqe->wr.wr.atomic.rkey);
333 ohdr->u.atomic_eth.swap_data = cpu_to_be64(
334 wqe->wr.wr.atomic.swap);
335 ohdr->u.atomic_eth.compare_data = cpu_to_be64(
336 wqe->wr.wr.atomic.compare_add);
337 hwords += sizeof(struct ib_atomic_eth) / 4;
338 if (newreq) {
339 qp->s_lsn++;
340 wqe->lpsn = wqe->psn;
341 }
342 if (++qp->s_cur == qp->s_size)
343 qp->s_cur = 0;
344 ss = NULL;
345 len = 0;
346 break;
347
348 default:
349 goto done;
350 }
351 if (newreq) {
352 qp->s_tail++;
353 if (qp->s_tail >= qp->s_size)
354 qp->s_tail = 0;
355 }
356 bth2 |= qp->s_psn++ & IPS_PSN_MASK;
357 if ((int)(qp->s_psn - qp->s_next_psn) > 0)
358 qp->s_next_psn = qp->s_psn;
359 spin_lock(&dev->pending_lock);
360 if (list_empty(&qp->timerwait))
361 list_add_tail(&qp->timerwait,
362 &dev->pending[dev->pending_index]);
363 spin_unlock(&dev->pending_lock);
364 break;
365
366 case OP(RDMA_READ_RESPONSE_FIRST):
367 /*
368 * This case can only happen if a send is restarted. See
369 * ipath_restart_rc().
370 */
371 ipath_init_restart(qp, wqe);
372 /* FALLTHROUGH */
373 case OP(SEND_FIRST):
374 qp->s_state = OP(SEND_MIDDLE);
375 /* FALLTHROUGH */
376 case OP(SEND_MIDDLE):
377 bth2 = qp->s_psn++ & IPS_PSN_MASK;
378 if ((int)(qp->s_psn - qp->s_next_psn) > 0)
379 qp->s_next_psn = qp->s_psn;
380 ss = &qp->s_sge;
381 len = qp->s_len;
382 if (len > pmtu) {
383 /*
384 * Request an ACK every 1/2 MB to avoid retransmit
385 * timeouts.
386 */
387 if (((wqe->length - len) % (512 * 1024)) == 0)
388 bth2 |= 1 << 31;
389 len = pmtu;
390 break;
391 }
392 if (wqe->wr.opcode == IB_WR_SEND)
393 qp->s_state = OP(SEND_LAST);
394 else {
395 qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE);
396 /* Immediate data comes after the BTH */
397 ohdr->u.imm_data = wqe->wr.imm_data;
398 hwords += 1;
399 }
400 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
401 bth0 |= 1 << 23;
402 bth2 |= 1 << 31; /* Request ACK. */
403 qp->s_cur++;
404 if (qp->s_cur >= qp->s_size)
405 qp->s_cur = 0;
406 break;
407
408 case OP(RDMA_READ_RESPONSE_LAST):
409 /*
410 * This case can only happen if a RDMA write is restarted.
411 * See ipath_restart_rc().
412 */
413 ipath_init_restart(qp, wqe);
414 /* FALLTHROUGH */
415 case OP(RDMA_WRITE_FIRST):
416 qp->s_state = OP(RDMA_WRITE_MIDDLE);
417 /* FALLTHROUGH */
418 case OP(RDMA_WRITE_MIDDLE):
419 bth2 = qp->s_psn++ & IPS_PSN_MASK;
420 if ((int)(qp->s_psn - qp->s_next_psn) > 0)
421 qp->s_next_psn = qp->s_psn;
422 ss = &qp->s_sge;
423 len = qp->s_len;
424 if (len > pmtu) {
425 /*
426 * Request an ACK every 1/2 MB to avoid retransmit
427 * timeouts.
428 */
429 if (((wqe->length - len) % (512 * 1024)) == 0)
430 bth2 |= 1 << 31;
431 len = pmtu;
432 break;
433 }
434 if (wqe->wr.opcode == IB_WR_RDMA_WRITE)
435 qp->s_state = OP(RDMA_WRITE_LAST);
436 else {
437 qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE);
438 /* Immediate data comes after the BTH */
439 ohdr->u.imm_data = wqe->wr.imm_data;
440 hwords += 1;
441 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
442 bth0 |= 1 << 23;
443 }
444 bth2 |= 1 << 31; /* Request ACK. */
445 qp->s_cur++;
446 if (qp->s_cur >= qp->s_size)
447 qp->s_cur = 0;
448 break;
449
450 case OP(RDMA_READ_RESPONSE_MIDDLE):
451 /*
452 * This case can only happen if a RDMA read is restarted.
453 * See ipath_restart_rc().
454 */
455 ipath_init_restart(qp, wqe);
456 len = ((qp->s_psn - wqe->psn) & IPS_PSN_MASK) * pmtu;
457 ohdr->u.rc.reth.vaddr =
458 cpu_to_be64(wqe->wr.wr.rdma.remote_addr + len);
459 ohdr->u.rc.reth.rkey =
460 cpu_to_be32(wqe->wr.wr.rdma.rkey);
461 ohdr->u.rc.reth.length = cpu_to_be32(qp->s_len);
462 qp->s_state = OP(RDMA_READ_REQUEST);
463 hwords += sizeof(ohdr->u.rc.reth) / 4;
464 bth2 = qp->s_psn++ & IPS_PSN_MASK;
465 if ((int)(qp->s_psn - qp->s_next_psn) > 0)
466 qp->s_next_psn = qp->s_psn;
467 ss = NULL;
468 len = 0;
469 qp->s_cur++;
470 if (qp->s_cur == qp->s_size)
471 qp->s_cur = 0;
472 break;
473
474 case OP(RDMA_READ_REQUEST):
475 case OP(COMPARE_SWAP):
476 case OP(FETCH_ADD):
477 /*
478 * We shouldn't start anything new until this request is
479 * finished. The ACK will handle rescheduling us. XXX The
480 * number of outstanding ones is negotiated at connection
481 * setup time (see pg. 258,289)? XXX Also, if we support
482 * multiple outstanding requests, we need to check the WQE
483 * IB_SEND_FENCE flag and not send a new request if a RDMA
484 * read or atomic is pending.
485 */
486 goto done;
487 }
488 qp->s_len -= len;
489 qp->s_hdrwords = hwords;
490 qp->s_cur_sge = ss;
491 qp->s_cur_size = len;
492 *bth0p = bth0 | (qp->s_state << 24);
493 *bth2p = bth2;
494 return 1;
495
496 done:
497 return 0;
498 }
499
500 static inline void ipath_make_rc_grh(struct ipath_qp *qp,
501 struct ib_global_route *grh,
502 u32 nwords)
503 {
504 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
505
506 /* GRH header size in 32-bit words. */
507 qp->s_hdrwords += 10;
508 qp->s_hdr.u.l.grh.version_tclass_flow =
509 cpu_to_be32((6 << 28) |
510 (grh->traffic_class << 20) |
511 grh->flow_label);
512 qp->s_hdr.u.l.grh.paylen =
513 cpu_to_be16(((qp->s_hdrwords - 12) + nwords +
514 SIZE_OF_CRC) << 2);
515 /* next_hdr is defined by C8-7 in ch. 8.4.1 */
516 qp->s_hdr.u.l.grh.next_hdr = 0x1B;
517 qp->s_hdr.u.l.grh.hop_limit = grh->hop_limit;
518 /* The SGID is 32-bit aligned. */
519 qp->s_hdr.u.l.grh.sgid.global.subnet_prefix = dev->gid_prefix;
520 qp->s_hdr.u.l.grh.sgid.global.interface_id =
521 ipath_layer_get_guid(dev->dd);
522 qp->s_hdr.u.l.grh.dgid = grh->dgid;
523 }
524
525 /**
526 * ipath_do_rc_send - perform a send on an RC QP
527 * @data: contains a pointer to the QP
528 *
529 * Process entries in the send work queue until credit or queue is
530 * exhausted. Only allow one CPU to send a packet per QP (tasklet).
531 * Otherwise, after we drop the QP s_lock, two threads could send
532 * packets out of order.
533 */
534 void ipath_do_rc_send(unsigned long data)
535 {
536 struct ipath_qp *qp = (struct ipath_qp *)data;
537 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
538 unsigned long flags;
539 u16 lrh0;
540 u32 nwords;
541 u32 extra_bytes;
542 u32 bth0;
543 u32 bth2;
544 u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
545 struct ipath_other_headers *ohdr;
546
547 if (test_and_set_bit(IPATH_S_BUSY, &qp->s_flags))
548 goto bail;
549
550 if (unlikely(qp->remote_ah_attr.dlid ==
551 ipath_layer_get_lid(dev->dd))) {
552 struct ib_wc wc;
553
554 /*
555 * Pass in an uninitialized ib_wc to be consistent with
556 * other places where ipath_ruc_loopback() is called.
557 */
558 ipath_ruc_loopback(qp, &wc);
559 goto clear;
560 }
561
562 ohdr = &qp->s_hdr.u.oth;
563 if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)
564 ohdr = &qp->s_hdr.u.l.oth;
565
566 again:
567 /* Check for a constructed packet to be sent. */
568 if (qp->s_hdrwords != 0) {
569 /*
570 * If no PIO bufs are available, return. An interrupt will
571 * call ipath_ib_piobufavail() when one is available.
572 */
573 _VERBS_INFO("h %u %p\n", qp->s_hdrwords, &qp->s_hdr);
574 _VERBS_INFO("d %u %p %u %p %u %u %u %u\n", qp->s_cur_size,
575 qp->s_cur_sge->sg_list,
576 qp->s_cur_sge->num_sge,
577 qp->s_cur_sge->sge.vaddr,
578 qp->s_cur_sge->sge.sge_length,
579 qp->s_cur_sge->sge.length,
580 qp->s_cur_sge->sge.m,
581 qp->s_cur_sge->sge.n);
582 if (ipath_verbs_send(dev->dd, qp->s_hdrwords,
583 (u32 *) &qp->s_hdr, qp->s_cur_size,
584 qp->s_cur_sge)) {
585 ipath_no_bufs_available(qp, dev);
586 goto bail;
587 }
588 dev->n_unicast_xmit++;
589 /* Record that we sent the packet and s_hdr is empty. */
590 qp->s_hdrwords = 0;
591 }
592
593 /*
594 * The lock is needed to synchronize between setting
595 * qp->s_ack_state, resend timer, and post_send().
596 */
597 spin_lock_irqsave(&qp->s_lock, flags);
598
599 /* Sending responses has higher priority over sending requests. */
600 if (qp->s_ack_state != OP(ACKNOWLEDGE) &&
601 (bth0 = ipath_make_rc_ack(qp, ohdr, pmtu)) != 0)
602 bth2 = qp->s_ack_psn++ & IPS_PSN_MASK;
603 else if (!ipath_make_rc_req(qp, ohdr, pmtu, &bth0, &bth2))
604 goto done;
605
606 spin_unlock_irqrestore(&qp->s_lock, flags);
607
608 /* Construct the header. */
609 extra_bytes = (4 - qp->s_cur_size) & 3;
610 nwords = (qp->s_cur_size + extra_bytes) >> 2;
611 lrh0 = IPS_LRH_BTH;
612 if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
613 ipath_make_rc_grh(qp, &qp->remote_ah_attr.grh, nwords);
614 lrh0 = IPS_LRH_GRH;
615 }
616 lrh0 |= qp->remote_ah_attr.sl << 4;
617 qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
618 qp->s_hdr.lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid);
619 qp->s_hdr.lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords +
620 SIZE_OF_CRC);
621 qp->s_hdr.lrh[3] = cpu_to_be16(ipath_layer_get_lid(dev->dd));
622 bth0 |= ipath_layer_get_pkey(dev->dd, qp->s_pkey_index);
623 bth0 |= extra_bytes << 20;
624 ohdr->bth[0] = cpu_to_be32(bth0);
625 ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
626 ohdr->bth[2] = cpu_to_be32(bth2);
627
628 /* Check for more work to do. */
629 goto again;
630
631 done:
632 spin_unlock_irqrestore(&qp->s_lock, flags);
633 clear:
634 clear_bit(IPATH_S_BUSY, &qp->s_flags);
635 bail:
636 return;
637 }
638
639 static void send_rc_ack(struct ipath_qp *qp)
640 {
641 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
642 u16 lrh0;
643 u32 bth0;
644 struct ipath_other_headers *ohdr;
645
646 /* Construct the header. */
647 ohdr = &qp->s_hdr.u.oth;
648 lrh0 = IPS_LRH_BTH;
649 /* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4. */
650 qp->s_hdrwords = 6;
651 if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
652 ipath_make_rc_grh(qp, &qp->remote_ah_attr.grh, 0);
653 ohdr = &qp->s_hdr.u.l.oth;
654 lrh0 = IPS_LRH_GRH;
655 }
656 bth0 = ipath_layer_get_pkey(dev->dd, qp->s_pkey_index);
657 ohdr->u.aeth = ipath_compute_aeth(qp);
658 if (qp->s_ack_state >= OP(COMPARE_SWAP)) {
659 bth0 |= IB_OPCODE_ATOMIC_ACKNOWLEDGE << 24;
660 ohdr->u.at.atomic_ack_eth = cpu_to_be64(qp->s_ack_atomic);
661 qp->s_hdrwords += sizeof(ohdr->u.at.atomic_ack_eth) / 4;
662 }
663 else
664 bth0 |= OP(ACKNOWLEDGE) << 24;
665 lrh0 |= qp->remote_ah_attr.sl << 4;
666 qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
667 qp->s_hdr.lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid);
668 qp->s_hdr.lrh[2] = cpu_to_be16(qp->s_hdrwords + SIZE_OF_CRC);
669 qp->s_hdr.lrh[3] = cpu_to_be16(ipath_layer_get_lid(dev->dd));
670 ohdr->bth[0] = cpu_to_be32(bth0);
671 ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
672 ohdr->bth[2] = cpu_to_be32(qp->s_ack_psn & IPS_PSN_MASK);
673
674 /*
675 * If we can send the ACK, clear the ACK state.
676 */
677 if (ipath_verbs_send(dev->dd, qp->s_hdrwords, (u32 *) &qp->s_hdr,
678 0, NULL) == 0) {
679 qp->s_ack_state = OP(ACKNOWLEDGE);
680 dev->n_rc_qacks++;
681 dev->n_unicast_xmit++;
682 }
683 }
684
685 /**
686 * ipath_restart_rc - back up requester to resend the last un-ACKed request
687 * @qp: the QP to restart
688 * @psn: packet sequence number for the request
689 * @wc: the work completion request
690 *
691 * The QP s_lock should be held.
692 */
693 void ipath_restart_rc(struct ipath_qp *qp, u32 psn, struct ib_wc *wc)
694 {
695 struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
696 struct ipath_ibdev *dev;
697 u32 n;
698
699 /*
700 * If there are no requests pending, we are done.
701 */
702 if (ipath_cmp24(psn, qp->s_next_psn) >= 0 ||
703 qp->s_last == qp->s_tail)
704 goto done;
705
706 if (qp->s_retry == 0) {
707 wc->wr_id = wqe->wr.wr_id;
708 wc->status = IB_WC_RETRY_EXC_ERR;
709 wc->opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
710 wc->vendor_err = 0;
711 wc->byte_len = 0;
712 wc->qp_num = qp->ibqp.qp_num;
713 wc->src_qp = qp->remote_qpn;
714 wc->pkey_index = 0;
715 wc->slid = qp->remote_ah_attr.dlid;
716 wc->sl = qp->remote_ah_attr.sl;
717 wc->dlid_path_bits = 0;
718 wc->port_num = 0;
719 ipath_sqerror_qp(qp, wc);
720 goto bail;
721 }
722 qp->s_retry--;
723
724 /*
725 * Remove the QP from the timeout queue.
726 * Note: it may already have been removed by ipath_ib_timer().
727 */
728 dev = to_idev(qp->ibqp.device);
729 spin_lock(&dev->pending_lock);
730 if (!list_empty(&qp->timerwait))
731 list_del_init(&qp->timerwait);
732 spin_unlock(&dev->pending_lock);
733
734 if (wqe->wr.opcode == IB_WR_RDMA_READ)
735 dev->n_rc_resends++;
736 else
737 dev->n_rc_resends += (int)qp->s_psn - (int)psn;
738
739 /*
740 * If we are starting the request from the beginning, let the normal
741 * send code handle initialization.
742 */
743 qp->s_cur = qp->s_last;
744 if (ipath_cmp24(psn, wqe->psn) <= 0) {
745 qp->s_state = OP(SEND_LAST);
746 qp->s_psn = wqe->psn;
747 } else {
748 n = qp->s_cur;
749 for (;;) {
750 if (++n == qp->s_size)
751 n = 0;
752 if (n == qp->s_tail) {
753 if (ipath_cmp24(psn, qp->s_next_psn) >= 0) {
754 qp->s_cur = n;
755 wqe = get_swqe_ptr(qp, n);
756 }
757 break;
758 }
759 wqe = get_swqe_ptr(qp, n);
760 if (ipath_cmp24(psn, wqe->psn) < 0)
761 break;
762 qp->s_cur = n;
763 }
764 qp->s_psn = psn;
765
766 /*
767 * Reset the state to restart in the middle of a request.
768 * Don't change the s_sge, s_cur_sge, or s_cur_size.
769 * See ipath_do_rc_send().
770 */
771 switch (wqe->wr.opcode) {
772 case IB_WR_SEND:
773 case IB_WR_SEND_WITH_IMM:
774 qp->s_state = OP(RDMA_READ_RESPONSE_FIRST);
775 break;
776
777 case IB_WR_RDMA_WRITE:
778 case IB_WR_RDMA_WRITE_WITH_IMM:
779 qp->s_state = OP(RDMA_READ_RESPONSE_LAST);
780 break;
781
782 case IB_WR_RDMA_READ:
783 qp->s_state =
784 OP(RDMA_READ_RESPONSE_MIDDLE);
785 break;
786
787 default:
788 /*
789 * This case shouldn't happen since its only
790 * one PSN per req.
791 */
792 qp->s_state = OP(SEND_LAST);
793 }
794 }
795
796 done:
797 tasklet_hi_schedule(&qp->s_task);
798
799 bail:
800 return;
801 }
802
803 /**
804 * reset_psn - reset the QP state to send starting from PSN
805 * @qp: the QP
806 * @psn: the packet sequence number to restart at
807 *
808 * This is called from ipath_rc_rcv() to process an incoming RC ACK
809 * for the given QP.
810 * Called at interrupt level with the QP s_lock held.
811 */
812 static void reset_psn(struct ipath_qp *qp, u32 psn)
813 {
814 struct ipath_swqe *wqe;
815 u32 n;
816
817 n = qp->s_cur;
818 wqe = get_swqe_ptr(qp, n);
819 for (;;) {
820 if (++n == qp->s_size)
821 n = 0;
822 if (n == qp->s_tail) {
823 if (ipath_cmp24(psn, qp->s_next_psn) >= 0) {
824 qp->s_cur = n;
825 wqe = get_swqe_ptr(qp, n);
826 }
827 break;
828 }
829 wqe = get_swqe_ptr(qp, n);
830 if (ipath_cmp24(psn, wqe->psn) < 0)
831 break;
832 qp->s_cur = n;
833 }
834 qp->s_psn = psn;
835
836 /*
837 * Set the state to restart in the middle of a
838 * request. Don't change the s_sge, s_cur_sge, or
839 * s_cur_size. See ipath_do_rc_send().
840 */
841 switch (wqe->wr.opcode) {
842 case IB_WR_SEND:
843 case IB_WR_SEND_WITH_IMM:
844 qp->s_state = OP(RDMA_READ_RESPONSE_FIRST);
845 break;
846
847 case IB_WR_RDMA_WRITE:
848 case IB_WR_RDMA_WRITE_WITH_IMM:
849 qp->s_state = OP(RDMA_READ_RESPONSE_LAST);
850 break;
851
852 case IB_WR_RDMA_READ:
853 qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE);
854 break;
855
856 default:
857 /*
858 * This case shouldn't happen since its only
859 * one PSN per req.
860 */
861 qp->s_state = OP(SEND_LAST);
862 }
863 }
864
865 /**
866 * do_rc_ack - process an incoming RC ACK
867 * @qp: the QP the ACK came in on
868 * @psn: the packet sequence number of the ACK
869 * @opcode: the opcode of the request that resulted in the ACK
870 *
871 * This is called from ipath_rc_rcv() to process an incoming RC ACK
872 * for the given QP.
873 * Called at interrupt level with the QP s_lock held.
874 * Returns 1 if OK, 0 if current operation should be aborted (NAK).
875 */
876 static int do_rc_ack(struct ipath_qp *qp, u32 aeth, u32 psn, int opcode)
877 {
878 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
879 struct ib_wc wc;
880 struct ipath_swqe *wqe;
881 int ret = 0;
882
883 /*
884 * Remove the QP from the timeout queue (or RNR timeout queue).
885 * If ipath_ib_timer() has already removed it,
886 * it's OK since we hold the QP s_lock and ipath_restart_rc()
887 * just won't find anything to restart if we ACK everything.
888 */
889 spin_lock(&dev->pending_lock);
890 if (!list_empty(&qp->timerwait))
891 list_del_init(&qp->timerwait);
892 spin_unlock(&dev->pending_lock);
893
894 /*
895 * Note that NAKs implicitly ACK outstanding SEND and RDMA write
896 * requests and implicitly NAK RDMA read and atomic requests issued
897 * before the NAK'ed request. The MSN won't include the NAK'ed
898 * request but will include an ACK'ed request(s).
899 */
900 wqe = get_swqe_ptr(qp, qp->s_last);
901
902 /* Nothing is pending to ACK/NAK. */
903 if (qp->s_last == qp->s_tail)
904 goto bail;
905
906 /*
907 * The MSN might be for a later WQE than the PSN indicates so
908 * only complete WQEs that the PSN finishes.
909 */
910 while (ipath_cmp24(psn, wqe->lpsn) >= 0) {
911 /* If we are ACKing a WQE, the MSN should be >= the SSN. */
912 if (ipath_cmp24(aeth, wqe->ssn) < 0)
913 break;
914 /*
915 * If this request is a RDMA read or atomic, and the ACK is
916 * for a later operation, this ACK NAKs the RDMA read or
917 * atomic. In other words, only a RDMA_READ_LAST or ONLY
918 * can ACK a RDMA read and likewise for atomic ops. Note
919 * that the NAK case can only happen if relaxed ordering is
920 * used and requests are sent after an RDMA read or atomic
921 * is sent but before the response is received.
922 */
923 if ((wqe->wr.opcode == IB_WR_RDMA_READ &&
924 opcode != OP(RDMA_READ_RESPONSE_LAST)) ||
925 ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
926 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) &&
927 (opcode != OP(ATOMIC_ACKNOWLEDGE) ||
928 ipath_cmp24(wqe->psn, psn) != 0))) {
929 /*
930 * The last valid PSN seen is the previous
931 * request's.
932 */
933 qp->s_last_psn = wqe->psn - 1;
934 /* Retry this request. */
935 ipath_restart_rc(qp, wqe->psn, &wc);
936 /*
937 * No need to process the ACK/NAK since we are
938 * restarting an earlier request.
939 */
940 goto bail;
941 }
942 /* Post a send completion queue entry if requested. */
943 if (!test_bit(IPATH_S_SIGNAL_REQ_WR, &qp->s_flags) ||
944 (wqe->wr.send_flags & IB_SEND_SIGNALED)) {
945 wc.wr_id = wqe->wr.wr_id;
946 wc.status = IB_WC_SUCCESS;
947 wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
948 wc.vendor_err = 0;
949 wc.byte_len = wqe->length;
950 wc.qp_num = qp->ibqp.qp_num;
951 wc.src_qp = qp->remote_qpn;
952 wc.pkey_index = 0;
953 wc.slid = qp->remote_ah_attr.dlid;
954 wc.sl = qp->remote_ah_attr.sl;
955 wc.dlid_path_bits = 0;
956 wc.port_num = 0;
957 ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 0);
958 }
959 qp->s_retry = qp->s_retry_cnt;
960 /*
961 * If we are completing a request which is in the process of
962 * being resent, we can stop resending it since we know the
963 * responder has already seen it.
964 */
965 if (qp->s_last == qp->s_cur) {
966 if (++qp->s_cur >= qp->s_size)
967 qp->s_cur = 0;
968 wqe = get_swqe_ptr(qp, qp->s_cur);
969 qp->s_state = OP(SEND_LAST);
970 qp->s_psn = wqe->psn;
971 }
972 if (++qp->s_last >= qp->s_size)
973 qp->s_last = 0;
974 wqe = get_swqe_ptr(qp, qp->s_last);
975 if (qp->s_last == qp->s_tail)
976 break;
977 }
978
979 switch (aeth >> 29) {
980 case 0: /* ACK */
981 dev->n_rc_acks++;
982 /* If this is a partial ACK, reset the retransmit timer. */
983 if (qp->s_last != qp->s_tail) {
984 spin_lock(&dev->pending_lock);
985 list_add_tail(&qp->timerwait,
986 &dev->pending[dev->pending_index]);
987 spin_unlock(&dev->pending_lock);
988 }
989 ipath_get_credit(qp, aeth);
990 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
991 qp->s_retry = qp->s_retry_cnt;
992 qp->s_last_psn = psn;
993 ret = 1;
994 goto bail;
995
996 case 1: /* RNR NAK */
997 dev->n_rnr_naks++;
998 if (qp->s_rnr_retry == 0) {
999 if (qp->s_last == qp->s_tail)
1000 goto bail;
1001
1002 wc.status = IB_WC_RNR_RETRY_EXC_ERR;
1003 goto class_b;
1004 }
1005 if (qp->s_rnr_retry_cnt < 7)
1006 qp->s_rnr_retry--;
1007 if (qp->s_last == qp->s_tail)
1008 goto bail;
1009
1010 /* The last valid PSN seen is the previous request's. */
1011 qp->s_last_psn = wqe->psn - 1;
1012
1013 dev->n_rc_resends += (int)qp->s_psn - (int)psn;
1014
1015 /*
1016 * If we are starting the request from the beginning, let
1017 * the normal send code handle initialization.
1018 */
1019 qp->s_cur = qp->s_last;
1020 wqe = get_swqe_ptr(qp, qp->s_cur);
1021 if (ipath_cmp24(psn, wqe->psn) <= 0) {
1022 qp->s_state = OP(SEND_LAST);
1023 qp->s_psn = wqe->psn;
1024 } else
1025 reset_psn(qp, psn);
1026
1027 qp->s_rnr_timeout =
1028 ib_ipath_rnr_table[(aeth >> IPS_AETH_CREDIT_SHIFT) &
1029 IPS_AETH_CREDIT_MASK];
1030 ipath_insert_rnr_queue(qp);
1031 goto bail;
1032
1033 case 3: /* NAK */
1034 /* The last valid PSN seen is the previous request's. */
1035 if (qp->s_last != qp->s_tail)
1036 qp->s_last_psn = wqe->psn - 1;
1037 switch ((aeth >> IPS_AETH_CREDIT_SHIFT) &
1038 IPS_AETH_CREDIT_MASK) {
1039 case 0: /* PSN sequence error */
1040 dev->n_seq_naks++;
1041 /*
1042 * Back up to the responder's expected PSN. XXX
1043 * Note that we might get a NAK in the middle of an
1044 * RDMA READ response which terminates the RDMA
1045 * READ.
1046 */
1047 if (qp->s_last == qp->s_tail)
1048 break;
1049
1050 if (ipath_cmp24(psn, wqe->psn) < 0)
1051 break;
1052
1053 /* Retry the request. */
1054 ipath_restart_rc(qp, psn, &wc);
1055 break;
1056
1057 case 1: /* Invalid Request */
1058 wc.status = IB_WC_REM_INV_REQ_ERR;
1059 dev->n_other_naks++;
1060 goto class_b;
1061
1062 case 2: /* Remote Access Error */
1063 wc.status = IB_WC_REM_ACCESS_ERR;
1064 dev->n_other_naks++;
1065 goto class_b;
1066
1067 case 3: /* Remote Operation Error */
1068 wc.status = IB_WC_REM_OP_ERR;
1069 dev->n_other_naks++;
1070 class_b:
1071 wc.wr_id = wqe->wr.wr_id;
1072 wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
1073 wc.vendor_err = 0;
1074 wc.byte_len = 0;
1075 wc.qp_num = qp->ibqp.qp_num;
1076 wc.src_qp = qp->remote_qpn;
1077 wc.pkey_index = 0;
1078 wc.slid = qp->remote_ah_attr.dlid;
1079 wc.sl = qp->remote_ah_attr.sl;
1080 wc.dlid_path_bits = 0;
1081 wc.port_num = 0;
1082 ipath_sqerror_qp(qp, &wc);
1083 break;
1084
1085 default:
1086 /* Ignore other reserved NAK error codes */
1087 goto reserved;
1088 }
1089 qp->s_rnr_retry = qp->s_rnr_retry_cnt;
1090 goto bail;
1091
1092 default: /* 2: reserved */
1093 reserved:
1094 /* Ignore reserved NAK codes. */
1095 goto bail;
1096 }
1097
1098 bail:
1099 return ret;
1100 }
1101
1102 /**
1103 * ipath_rc_rcv_resp - process an incoming RC response packet
1104 * @dev: the device this packet came in on
1105 * @ohdr: the other headers for this packet
1106 * @data: the packet data
1107 * @tlen: the packet length
1108 * @qp: the QP for this packet
1109 * @opcode: the opcode for this packet
1110 * @psn: the packet sequence number for this packet
1111 * @hdrsize: the header length
1112 * @pmtu: the path MTU
1113 * @header_in_data: true if part of the header data is in the data buffer
1114 *
1115 * This is called from ipath_rc_rcv() to process an incoming RC response
1116 * packet for the given QP.
1117 * Called at interrupt level.
1118 */
1119 static inline void ipath_rc_rcv_resp(struct ipath_ibdev *dev,
1120 struct ipath_other_headers *ohdr,
1121 void *data, u32 tlen,
1122 struct ipath_qp *qp,
1123 u32 opcode,
1124 u32 psn, u32 hdrsize, u32 pmtu,
1125 int header_in_data)
1126 {
1127 unsigned long flags;
1128 struct ib_wc wc;
1129 int diff;
1130 u32 pad;
1131 u32 aeth;
1132
1133 spin_lock_irqsave(&qp->s_lock, flags);
1134
1135 /* Ignore invalid responses. */
1136 if (ipath_cmp24(psn, qp->s_next_psn) >= 0)
1137 goto ack_done;
1138
1139 /* Ignore duplicate responses. */
1140 diff = ipath_cmp24(psn, qp->s_last_psn);
1141 if (unlikely(diff <= 0)) {
1142 /* Update credits for "ghost" ACKs */
1143 if (diff == 0 && opcode == OP(ACKNOWLEDGE)) {
1144 if (!header_in_data)
1145 aeth = be32_to_cpu(ohdr->u.aeth);
1146 else {
1147 aeth = be32_to_cpu(((__be32 *) data)[0]);
1148 data += sizeof(__be32);
1149 }
1150 if ((aeth >> 29) == 0)
1151 ipath_get_credit(qp, aeth);
1152 }
1153 goto ack_done;
1154 }
1155
1156 switch (opcode) {
1157 case OP(ACKNOWLEDGE):
1158 case OP(ATOMIC_ACKNOWLEDGE):
1159 case OP(RDMA_READ_RESPONSE_FIRST):
1160 if (!header_in_data)
1161 aeth = be32_to_cpu(ohdr->u.aeth);
1162 else {
1163 aeth = be32_to_cpu(((__be32 *) data)[0]);
1164 data += sizeof(__be32);
1165 }
1166 if (opcode == OP(ATOMIC_ACKNOWLEDGE))
1167 *(u64 *) qp->s_sge.sge.vaddr = *(u64 *) data;
1168 if (!do_rc_ack(qp, aeth, psn, opcode) ||
1169 opcode != OP(RDMA_READ_RESPONSE_FIRST))
1170 goto ack_done;
1171 hdrsize += 4;
1172 /*
1173 * do_rc_ack() has already checked the PSN so skip
1174 * the sequence check.
1175 */
1176 goto rdma_read;
1177
1178 case OP(RDMA_READ_RESPONSE_MIDDLE):
1179 /* no AETH, no ACK */
1180 if (unlikely(ipath_cmp24(psn, qp->s_last_psn + 1))) {
1181 dev->n_rdma_seq++;
1182 ipath_restart_rc(qp, qp->s_last_psn + 1, &wc);
1183 goto ack_done;
1184 }
1185 rdma_read:
1186 if (unlikely(qp->s_state != OP(RDMA_READ_REQUEST)))
1187 goto ack_done;
1188 if (unlikely(tlen != (hdrsize + pmtu + 4)))
1189 goto ack_done;
1190 if (unlikely(pmtu >= qp->s_len))
1191 goto ack_done;
1192 /* We got a response so update the timeout. */
1193 if (unlikely(qp->s_last == qp->s_tail ||
1194 get_swqe_ptr(qp, qp->s_last)->wr.opcode !=
1195 IB_WR_RDMA_READ))
1196 goto ack_done;
1197 spin_lock(&dev->pending_lock);
1198 if (qp->s_rnr_timeout == 0 && !list_empty(&qp->timerwait))
1199 list_move_tail(&qp->timerwait,
1200 &dev->pending[dev->pending_index]);
1201 spin_unlock(&dev->pending_lock);
1202 /*
1203 * Update the RDMA receive state but do the copy w/o holding the
1204 * locks and blocking interrupts. XXX Yet another place that
1205 * affects relaxed RDMA order since we don't want s_sge modified.
1206 */
1207 qp->s_len -= pmtu;
1208 qp->s_last_psn = psn;
1209 spin_unlock_irqrestore(&qp->s_lock, flags);
1210 ipath_copy_sge(&qp->s_sge, data, pmtu);
1211 goto bail;
1212
1213 case OP(RDMA_READ_RESPONSE_LAST):
1214 /* ACKs READ req. */
1215 if (unlikely(ipath_cmp24(psn, qp->s_last_psn + 1))) {
1216 dev->n_rdma_seq++;
1217 ipath_restart_rc(qp, qp->s_last_psn + 1, &wc);
1218 goto ack_done;
1219 }
1220 /* FALLTHROUGH */
1221 case OP(RDMA_READ_RESPONSE_ONLY):
1222 if (unlikely(qp->s_state != OP(RDMA_READ_REQUEST)))
1223 goto ack_done;
1224 /*
1225 * Get the number of bytes the message was padded by.
1226 */
1227 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
1228 /*
1229 * Check that the data size is >= 1 && <= pmtu.
1230 * Remember to account for the AETH header (4) and
1231 * ICRC (4).
1232 */
1233 if (unlikely(tlen <= (hdrsize + pad + 8))) {
1234 /*
1235 * XXX Need to generate an error CQ
1236 * entry.
1237 */
1238 goto ack_done;
1239 }
1240 tlen -= hdrsize + pad + 8;
1241 if (unlikely(tlen != qp->s_len)) {
1242 /*
1243 * XXX Need to generate an error CQ
1244 * entry.
1245 */
1246 goto ack_done;
1247 }
1248 if (!header_in_data)
1249 aeth = be32_to_cpu(ohdr->u.aeth);
1250 else {
1251 aeth = be32_to_cpu(((__be32 *) data)[0]);
1252 data += sizeof(__be32);
1253 }
1254 ipath_copy_sge(&qp->s_sge, data, tlen);
1255 if (do_rc_ack(qp, aeth, psn, OP(RDMA_READ_RESPONSE_LAST))) {
1256 /*
1257 * Change the state so we contimue
1258 * processing new requests.
1259 */
1260 qp->s_state = OP(SEND_LAST);
1261 }
1262 goto ack_done;
1263 }
1264
1265 ack_done:
1266 spin_unlock_irqrestore(&qp->s_lock, flags);
1267 bail:
1268 return;
1269 }
1270
1271 /**
1272 * ipath_rc_rcv_error - process an incoming duplicate or error RC packet
1273 * @dev: the device this packet came in on
1274 * @ohdr: the other headers for this packet
1275 * @data: the packet data
1276 * @qp: the QP for this packet
1277 * @opcode: the opcode for this packet
1278 * @psn: the packet sequence number for this packet
1279 * @diff: the difference between the PSN and the expected PSN
1280 * @header_in_data: true if part of the header data is in the data buffer
1281 *
1282 * This is called from ipath_rc_rcv() to process an unexpected
1283 * incoming RC packet for the given QP.
1284 * Called at interrupt level.
1285 * Return 1 if no more processing is needed; otherwise return 0 to
1286 * schedule a response to be sent and the s_lock unlocked.
1287 */
1288 static inline int ipath_rc_rcv_error(struct ipath_ibdev *dev,
1289 struct ipath_other_headers *ohdr,
1290 void *data,
1291 struct ipath_qp *qp,
1292 u32 opcode,
1293 u32 psn,
1294 int diff,
1295 int header_in_data)
1296 {
1297 struct ib_reth *reth;
1298
1299 if (diff > 0) {
1300 /*
1301 * Packet sequence error.
1302 * A NAK will ACK earlier sends and RDMA writes.
1303 * Don't queue the NAK if a RDMA read, atomic, or
1304 * NAK is pending though.
1305 */
1306 spin_lock(&qp->s_lock);
1307 if ((qp->s_ack_state >= OP(RDMA_READ_REQUEST) &&
1308 qp->s_ack_state != IB_OPCODE_ACKNOWLEDGE) ||
1309 qp->s_nak_state != 0) {
1310 spin_unlock(&qp->s_lock);
1311 goto done;
1312 }
1313 qp->s_ack_state = OP(SEND_ONLY);
1314 qp->s_nak_state = IB_NAK_PSN_ERROR;
1315 /* Use the expected PSN. */
1316 qp->s_ack_psn = qp->r_psn;
1317 goto resched;
1318 }
1319
1320 /*
1321 * Handle a duplicate request. Don't re-execute SEND, RDMA
1322 * write or atomic op. Don't NAK errors, just silently drop
1323 * the duplicate request. Note that r_sge, r_len, and
1324 * r_rcv_len may be in use so don't modify them.
1325 *
1326 * We are supposed to ACK the earliest duplicate PSN but we
1327 * can coalesce an outstanding duplicate ACK. We have to
1328 * send the earliest so that RDMA reads can be restarted at
1329 * the requester's expected PSN.
1330 */
1331 spin_lock(&qp->s_lock);
1332 if (qp->s_ack_state != IB_OPCODE_ACKNOWLEDGE &&
1333 ipath_cmp24(psn, qp->s_ack_psn) >= 0) {
1334 if (qp->s_ack_state < IB_OPCODE_RDMA_READ_REQUEST)
1335 qp->s_ack_psn = psn;
1336 spin_unlock(&qp->s_lock);
1337 goto done;
1338 }
1339 switch (opcode) {
1340 case OP(RDMA_READ_REQUEST):
1341 /*
1342 * We have to be careful to not change s_rdma_sge
1343 * while ipath_do_rc_send() is using it and not
1344 * holding the s_lock.
1345 */
1346 if (qp->s_ack_state != OP(ACKNOWLEDGE) &&
1347 qp->s_ack_state >= IB_OPCODE_RDMA_READ_REQUEST) {
1348 spin_unlock(&qp->s_lock);
1349 dev->n_rdma_dup_busy++;
1350 goto done;
1351 }
1352 /* RETH comes after BTH */
1353 if (!header_in_data)
1354 reth = &ohdr->u.rc.reth;
1355 else {
1356 reth = (struct ib_reth *)data;
1357 data += sizeof(*reth);
1358 }
1359 qp->s_rdma_len = be32_to_cpu(reth->length);
1360 if (qp->s_rdma_len != 0) {
1361 u32 rkey = be32_to_cpu(reth->rkey);
1362 u64 vaddr = be64_to_cpu(reth->vaddr);
1363 int ok;
1364
1365 /*
1366 * Address range must be a subset of the original
1367 * request and start on pmtu boundaries.
1368 */
1369 ok = ipath_rkey_ok(dev, &qp->s_rdma_sge,
1370 qp->s_rdma_len, vaddr, rkey,
1371 IB_ACCESS_REMOTE_READ);
1372 if (unlikely(!ok))
1373 goto done;
1374 } else {
1375 qp->s_rdma_sge.sg_list = NULL;
1376 qp->s_rdma_sge.num_sge = 0;
1377 qp->s_rdma_sge.sge.mr = NULL;
1378 qp->s_rdma_sge.sge.vaddr = NULL;
1379 qp->s_rdma_sge.sge.length = 0;
1380 qp->s_rdma_sge.sge.sge_length = 0;
1381 }
1382 break;
1383
1384 case OP(COMPARE_SWAP):
1385 case OP(FETCH_ADD):
1386 /*
1387 * Check for the PSN of the last atomic operations
1388 * performed and resend the result if found.
1389 */
1390 if ((psn & IPS_PSN_MASK) != qp->r_atomic_psn) {
1391 spin_unlock(&qp->s_lock);
1392 goto done;
1393 }
1394 qp->s_ack_atomic = qp->r_atomic_data;
1395 break;
1396 }
1397 qp->s_ack_state = opcode;
1398 qp->s_nak_state = 0;
1399 qp->s_ack_psn = psn;
1400 resched:
1401 return 0;
1402
1403 done:
1404 return 1;
1405 }
1406
1407 /**
1408 * ipath_rc_rcv - process an incoming RC packet
1409 * @dev: the device this packet came in on
1410 * @hdr: the header of this packet
1411 * @has_grh: true if the header has a GRH
1412 * @data: the packet data
1413 * @tlen: the packet length
1414 * @qp: the QP for this packet
1415 *
1416 * This is called from ipath_qp_rcv() to process an incoming RC packet
1417 * for the given QP.
1418 * Called at interrupt level.
1419 */
1420 void ipath_rc_rcv(struct ipath_ibdev *dev, struct ipath_ib_header *hdr,
1421 int has_grh, void *data, u32 tlen, struct ipath_qp *qp)
1422 {
1423 struct ipath_other_headers *ohdr;
1424 u32 opcode;
1425 u32 hdrsize;
1426 u32 psn;
1427 u32 pad;
1428 unsigned long flags;
1429 struct ib_wc wc;
1430 u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
1431 int diff;
1432 struct ib_reth *reth;
1433 int header_in_data;
1434
1435 /* Check for GRH */
1436 if (!has_grh) {
1437 ohdr = &hdr->u.oth;
1438 hdrsize = 8 + 12; /* LRH + BTH */
1439 psn = be32_to_cpu(ohdr->bth[2]);
1440 header_in_data = 0;
1441 } else {
1442 ohdr = &hdr->u.l.oth;
1443 hdrsize = 8 + 40 + 12; /* LRH + GRH + BTH */
1444 /*
1445 * The header with GRH is 60 bytes and the core driver sets
1446 * the eager header buffer size to 56 bytes so the last 4
1447 * bytes of the BTH header (PSN) is in the data buffer.
1448 */
1449 header_in_data =
1450 ipath_layer_get_rcvhdrentsize(dev->dd) == 16;
1451 if (header_in_data) {
1452 psn = be32_to_cpu(((__be32 *) data)[0]);
1453 data += sizeof(__be32);
1454 } else
1455 psn = be32_to_cpu(ohdr->bth[2]);
1456 }
1457 /*
1458 * The opcode is in the low byte when its in network order
1459 * (top byte when in host order).
1460 */
1461 opcode = be32_to_cpu(ohdr->bth[0]) >> 24;
1462
1463 /*
1464 * Process responses (ACKs) before anything else. Note that the
1465 * packet sequence number will be for something in the send work
1466 * queue rather than the expected receive packet sequence number.
1467 * In other words, this QP is the requester.
1468 */
1469 if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1470 opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
1471 ipath_rc_rcv_resp(dev, ohdr, data, tlen, qp, opcode, psn,
1472 hdrsize, pmtu, header_in_data);
1473 goto bail;
1474 }
1475
1476 spin_lock_irqsave(&qp->r_rq.lock, flags);
1477
1478 /* Compute 24 bits worth of difference. */
1479 diff = ipath_cmp24(psn, qp->r_psn);
1480 if (unlikely(diff)) {
1481 if (ipath_rc_rcv_error(dev, ohdr, data, qp, opcode,
1482 psn, diff, header_in_data))
1483 goto done;
1484 goto resched;
1485 }
1486
1487 /* Check for opcode sequence errors. */
1488 switch (qp->r_state) {
1489 case OP(SEND_FIRST):
1490 case OP(SEND_MIDDLE):
1491 if (opcode == OP(SEND_MIDDLE) ||
1492 opcode == OP(SEND_LAST) ||
1493 opcode == OP(SEND_LAST_WITH_IMMEDIATE))
1494 break;
1495 nack_inv:
1496 /*
1497 * A NAK will ACK earlier sends and RDMA writes. Don't queue the
1498 * NAK if a RDMA read, atomic, or NAK is pending though.
1499 */
1500 spin_lock(&qp->s_lock);
1501 if (qp->s_ack_state >= OP(RDMA_READ_REQUEST) &&
1502 qp->s_ack_state != IB_OPCODE_ACKNOWLEDGE) {
1503 spin_unlock(&qp->s_lock);
1504 goto done;
1505 }
1506 /* XXX Flush WQEs */
1507 qp->state = IB_QPS_ERR;
1508 qp->s_ack_state = OP(SEND_ONLY);
1509 qp->s_nak_state = IB_NAK_INVALID_REQUEST;
1510 qp->s_ack_psn = qp->r_psn;
1511 goto resched;
1512
1513 case OP(RDMA_WRITE_FIRST):
1514 case OP(RDMA_WRITE_MIDDLE):
1515 if (opcode == OP(RDMA_WRITE_MIDDLE) ||
1516 opcode == OP(RDMA_WRITE_LAST) ||
1517 opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
1518 break;
1519 goto nack_inv;
1520
1521 case OP(RDMA_READ_REQUEST):
1522 case OP(COMPARE_SWAP):
1523 case OP(FETCH_ADD):
1524 /*
1525 * Drop all new requests until a response has been sent. A
1526 * new request then ACKs the RDMA response we sent. Relaxed
1527 * ordering would allow new requests to be processed but we
1528 * would need to keep a queue of rwqe's for all that are in
1529 * progress. Note that we can't RNR NAK this request since
1530 * the RDMA READ or atomic response is already queued to be
1531 * sent (unless we implement a response send queue).
1532 */
1533 goto done;
1534
1535 default:
1536 if (opcode == OP(SEND_MIDDLE) ||
1537 opcode == OP(SEND_LAST) ||
1538 opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
1539 opcode == OP(RDMA_WRITE_MIDDLE) ||
1540 opcode == OP(RDMA_WRITE_LAST) ||
1541 opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
1542 goto nack_inv;
1543 break;
1544 }
1545
1546 wc.imm_data = 0;
1547 wc.wc_flags = 0;
1548
1549 /* OK, process the packet. */
1550 switch (opcode) {
1551 case OP(SEND_FIRST):
1552 if (!ipath_get_rwqe(qp, 0)) {
1553 rnr_nak:
1554 /*
1555 * A RNR NAK will ACK earlier sends and RDMA writes.
1556 * Don't queue the NAK if a RDMA read or atomic
1557 * is pending though.
1558 */
1559 spin_lock(&qp->s_lock);
1560 if (qp->s_ack_state >=
1561 OP(RDMA_READ_REQUEST) &&
1562 qp->s_ack_state != IB_OPCODE_ACKNOWLEDGE) {
1563 spin_unlock(&qp->s_lock);
1564 goto done;
1565 }
1566 qp->s_ack_state = OP(SEND_ONLY);
1567 qp->s_nak_state = IB_RNR_NAK | qp->s_min_rnr_timer;
1568 qp->s_ack_psn = qp->r_psn;
1569 goto resched;
1570 }
1571 qp->r_rcv_len = 0;
1572 /* FALLTHROUGH */
1573 case OP(SEND_MIDDLE):
1574 case OP(RDMA_WRITE_MIDDLE):
1575 send_middle:
1576 /* Check for invalid length PMTU or posted rwqe len. */
1577 if (unlikely(tlen != (hdrsize + pmtu + 4)))
1578 goto nack_inv;
1579 qp->r_rcv_len += pmtu;
1580 if (unlikely(qp->r_rcv_len > qp->r_len))
1581 goto nack_inv;
1582 ipath_copy_sge(&qp->r_sge, data, pmtu);
1583 break;
1584
1585 case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
1586 /* consume RWQE */
1587 if (!ipath_get_rwqe(qp, 1))
1588 goto rnr_nak;
1589 goto send_last_imm;
1590
1591 case OP(SEND_ONLY):
1592 case OP(SEND_ONLY_WITH_IMMEDIATE):
1593 if (!ipath_get_rwqe(qp, 0))
1594 goto rnr_nak;
1595 qp->r_rcv_len = 0;
1596 if (opcode == OP(SEND_ONLY))
1597 goto send_last;
1598 /* FALLTHROUGH */
1599 case OP(SEND_LAST_WITH_IMMEDIATE):
1600 send_last_imm:
1601 if (header_in_data) {
1602 wc.imm_data = *(__be32 *) data;
1603 data += sizeof(__be32);
1604 } else {
1605 /* Immediate data comes after BTH */
1606 wc.imm_data = ohdr->u.imm_data;
1607 }
1608 hdrsize += 4;
1609 wc.wc_flags = IB_WC_WITH_IMM;
1610 /* FALLTHROUGH */
1611 case OP(SEND_LAST):
1612 case OP(RDMA_WRITE_LAST):
1613 send_last:
1614 /* Get the number of bytes the message was padded by. */
1615 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
1616 /* Check for invalid length. */
1617 /* XXX LAST len should be >= 1 */
1618 if (unlikely(tlen < (hdrsize + pad + 4)))
1619 goto nack_inv;
1620 /* Don't count the CRC. */
1621 tlen -= (hdrsize + pad + 4);
1622 wc.byte_len = tlen + qp->r_rcv_len;
1623 if (unlikely(wc.byte_len > qp->r_len))
1624 goto nack_inv;
1625 ipath_copy_sge(&qp->r_sge, data, tlen);
1626 atomic_inc(&qp->msn);
1627 if (opcode == OP(RDMA_WRITE_LAST) ||
1628 opcode == OP(RDMA_WRITE_ONLY))
1629 break;
1630 wc.wr_id = qp->r_wr_id;
1631 wc.status = IB_WC_SUCCESS;
1632 wc.opcode = IB_WC_RECV;
1633 wc.vendor_err = 0;
1634 wc.qp_num = qp->ibqp.qp_num;
1635 wc.src_qp = qp->remote_qpn;
1636 wc.pkey_index = 0;
1637 wc.slid = qp->remote_ah_attr.dlid;
1638 wc.sl = qp->remote_ah_attr.sl;
1639 wc.dlid_path_bits = 0;
1640 wc.port_num = 0;
1641 /* Signal completion event if the solicited bit is set. */
1642 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
1643 (ohdr->bth[0] &
1644 __constant_cpu_to_be32(1 << 23)) != 0);
1645 break;
1646
1647 case OP(RDMA_WRITE_FIRST):
1648 case OP(RDMA_WRITE_ONLY):
1649 case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
1650 /* consume RWQE */
1651 /* RETH comes after BTH */
1652 if (!header_in_data)
1653 reth = &ohdr->u.rc.reth;
1654 else {
1655 reth = (struct ib_reth *)data;
1656 data += sizeof(*reth);
1657 }
1658 hdrsize += sizeof(*reth);
1659 qp->r_len = be32_to_cpu(reth->length);
1660 qp->r_rcv_len = 0;
1661 if (qp->r_len != 0) {
1662 u32 rkey = be32_to_cpu(reth->rkey);
1663 u64 vaddr = be64_to_cpu(reth->vaddr);
1664 int ok;
1665
1666 /* Check rkey & NAK */
1667 ok = ipath_rkey_ok(dev, &qp->r_sge,
1668 qp->r_len, vaddr, rkey,
1669 IB_ACCESS_REMOTE_WRITE);
1670 if (unlikely(!ok)) {
1671 nack_acc:
1672 /*
1673 * A NAK will ACK earlier sends and RDMA
1674 * writes. Don't queue the NAK if a RDMA
1675 * read, atomic, or NAK is pending though.
1676 */
1677 spin_lock(&qp->s_lock);
1678 if (qp->s_ack_state >=
1679 OP(RDMA_READ_REQUEST) &&
1680 qp->s_ack_state !=
1681 IB_OPCODE_ACKNOWLEDGE) {
1682 spin_unlock(&qp->s_lock);
1683 goto done;
1684 }
1685 /* XXX Flush WQEs */
1686 qp->state = IB_QPS_ERR;
1687 qp->s_ack_state = OP(RDMA_WRITE_ONLY);
1688 qp->s_nak_state =
1689 IB_NAK_REMOTE_ACCESS_ERROR;
1690 qp->s_ack_psn = qp->r_psn;
1691 goto resched;
1692 }
1693 } else {
1694 qp->r_sge.sg_list = NULL;
1695 qp->r_sge.sge.mr = NULL;
1696 qp->r_sge.sge.vaddr = NULL;
1697 qp->r_sge.sge.length = 0;
1698 qp->r_sge.sge.sge_length = 0;
1699 }
1700 if (unlikely(!(qp->qp_access_flags &
1701 IB_ACCESS_REMOTE_WRITE)))
1702 goto nack_acc;
1703 if (opcode == OP(RDMA_WRITE_FIRST))
1704 goto send_middle;
1705 else if (opcode == OP(RDMA_WRITE_ONLY))
1706 goto send_last;
1707 if (!ipath_get_rwqe(qp, 1))
1708 goto rnr_nak;
1709 goto send_last_imm;
1710
1711 case OP(RDMA_READ_REQUEST):
1712 /* RETH comes after BTH */
1713 if (!header_in_data)
1714 reth = &ohdr->u.rc.reth;
1715 else {
1716 reth = (struct ib_reth *)data;
1717 data += sizeof(*reth);
1718 }
1719 spin_lock(&qp->s_lock);
1720 if (qp->s_ack_state != OP(ACKNOWLEDGE) &&
1721 qp->s_ack_state >= IB_OPCODE_RDMA_READ_REQUEST) {
1722 spin_unlock(&qp->s_lock);
1723 goto done;
1724 }
1725 qp->s_rdma_len = be32_to_cpu(reth->length);
1726 if (qp->s_rdma_len != 0) {
1727 u32 rkey = be32_to_cpu(reth->rkey);
1728 u64 vaddr = be64_to_cpu(reth->vaddr);
1729 int ok;
1730
1731 /* Check rkey & NAK */
1732 ok = ipath_rkey_ok(dev, &qp->s_rdma_sge,
1733 qp->s_rdma_len, vaddr, rkey,
1734 IB_ACCESS_REMOTE_READ);
1735 if (unlikely(!ok)) {
1736 spin_unlock(&qp->s_lock);
1737 goto nack_acc;
1738 }
1739 /*
1740 * Update the next expected PSN. We add 1 later
1741 * below, so only add the remainder here.
1742 */
1743 if (qp->s_rdma_len > pmtu)
1744 qp->r_psn += (qp->s_rdma_len - 1) / pmtu;
1745 } else {
1746 qp->s_rdma_sge.sg_list = NULL;
1747 qp->s_rdma_sge.num_sge = 0;
1748 qp->s_rdma_sge.sge.mr = NULL;
1749 qp->s_rdma_sge.sge.vaddr = NULL;
1750 qp->s_rdma_sge.sge.length = 0;
1751 qp->s_rdma_sge.sge.sge_length = 0;
1752 }
1753 if (unlikely(!(qp->qp_access_flags &
1754 IB_ACCESS_REMOTE_READ)))
1755 goto nack_acc;
1756 /*
1757 * We need to increment the MSN here instead of when we
1758 * finish sending the result since a duplicate request would
1759 * increment it more than once.
1760 */
1761 atomic_inc(&qp->msn);
1762 qp->s_ack_state = opcode;
1763 qp->s_nak_state = 0;
1764 qp->s_ack_psn = psn;
1765 qp->r_psn++;
1766 qp->r_state = opcode;
1767 goto rdmadone;
1768
1769 case OP(COMPARE_SWAP):
1770 case OP(FETCH_ADD): {
1771 struct ib_atomic_eth *ateth;
1772 u64 vaddr;
1773 u64 sdata;
1774 u32 rkey;
1775
1776 if (!header_in_data)
1777 ateth = &ohdr->u.atomic_eth;
1778 else {
1779 ateth = (struct ib_atomic_eth *)data;
1780 data += sizeof(*ateth);
1781 }
1782 vaddr = be64_to_cpu(ateth->vaddr);
1783 if (unlikely(vaddr & (sizeof(u64) - 1)))
1784 goto nack_inv;
1785 rkey = be32_to_cpu(ateth->rkey);
1786 /* Check rkey & NAK */
1787 if (unlikely(!ipath_rkey_ok(dev, &qp->r_sge,
1788 sizeof(u64), vaddr, rkey,
1789 IB_ACCESS_REMOTE_ATOMIC)))
1790 goto nack_acc;
1791 if (unlikely(!(qp->qp_access_flags &
1792 IB_ACCESS_REMOTE_ATOMIC)))
1793 goto nack_acc;
1794 /* Perform atomic OP and save result. */
1795 sdata = be64_to_cpu(ateth->swap_data);
1796 spin_lock(&dev->pending_lock);
1797 qp->r_atomic_data = *(u64 *) qp->r_sge.sge.vaddr;
1798 if (opcode == OP(FETCH_ADD))
1799 *(u64 *) qp->r_sge.sge.vaddr =
1800 qp->r_atomic_data + sdata;
1801 else if (qp->r_atomic_data ==
1802 be64_to_cpu(ateth->compare_data))
1803 *(u64 *) qp->r_sge.sge.vaddr = sdata;
1804 spin_unlock(&dev->pending_lock);
1805 atomic_inc(&qp->msn);
1806 qp->r_atomic_psn = psn & IPS_PSN_MASK;
1807 psn |= 1 << 31;
1808 break;
1809 }
1810
1811 default:
1812 /* Drop packet for unknown opcodes. */
1813 goto done;
1814 }
1815 qp->r_psn++;
1816 qp->r_state = opcode;
1817 /* Send an ACK if requested or required. */
1818 if (psn & (1 << 31)) {
1819 /*
1820 * Coalesce ACKs unless there is a RDMA READ or
1821 * ATOMIC pending.
1822 */
1823 spin_lock(&qp->s_lock);
1824 if (qp->s_ack_state == OP(ACKNOWLEDGE) ||
1825 qp->s_ack_state < IB_OPCODE_RDMA_READ_REQUEST) {
1826 qp->s_ack_state = opcode;
1827 qp->s_nak_state = 0;
1828 qp->s_ack_psn = psn;
1829 qp->s_ack_atomic = qp->r_atomic_data;
1830 goto resched;
1831 }
1832 spin_unlock(&qp->s_lock);
1833 }
1834 done:
1835 spin_unlock_irqrestore(&qp->r_rq.lock, flags);
1836 goto bail;
1837
1838 resched:
1839 /*
1840 * Try to send ACK right away but not if ipath_do_rc_send() is
1841 * active.
1842 */
1843 if (qp->s_hdrwords == 0 &&
1844 (qp->s_ack_state < IB_OPCODE_RDMA_READ_REQUEST ||
1845 qp->s_ack_state >= IB_OPCODE_COMPARE_SWAP))
1846 send_rc_ack(qp);
1847
1848 rdmadone:
1849 spin_unlock(&qp->s_lock);
1850 spin_unlock_irqrestore(&qp->r_rq.lock, flags);
1851
1852 /* Call ipath_do_rc_send() in another thread. */
1853 tasklet_hi_schedule(&qp->s_task);
1854
1855 bail:
1856 return;
1857 }
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree