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/spinlock.h>
35 #include <rdma/ib_smi.h>
36
37 #include "qib.h"
38 #include "qib_mad.h"
39
40 /*
41 * Switch to alternate path.
42 * The QP s_lock should be held and interrupts disabled.
43 */
qib_migrate_qp(struct rvt_qp * qp)44 void qib_migrate_qp(struct rvt_qp *qp)
45 {
46 struct ib_event ev;
47
48 qp->s_mig_state = IB_MIG_MIGRATED;
49 qp->remote_ah_attr = qp->alt_ah_attr;
50 qp->port_num = rdma_ah_get_port_num(&qp->alt_ah_attr);
51 qp->s_pkey_index = qp->s_alt_pkey_index;
52
53 ev.device = qp->ibqp.device;
54 ev.element.qp = &qp->ibqp;
55 ev.event = IB_EVENT_PATH_MIG;
56 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
57 }
58
get_sguid(struct qib_ibport * ibp,unsigned index)59 static __be64 get_sguid(struct qib_ibport *ibp, unsigned index)
60 {
61 if (!index) {
62 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
63
64 return ppd->guid;
65 }
66 return ibp->guids[index - 1];
67 }
68
gid_ok(union ib_gid * gid,__be64 gid_prefix,__be64 id)69 static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
70 {
71 return (gid->global.interface_id == id &&
72 (gid->global.subnet_prefix == gid_prefix ||
73 gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
74 }
75
76 /*
77 *
78 * This should be called with the QP r_lock held.
79 *
80 * The s_lock will be acquired around the qib_migrate_qp() call.
81 */
qib_ruc_check_hdr(struct qib_ibport * ibp,struct ib_header * hdr,int has_grh,struct rvt_qp * qp,u32 bth0)82 int qib_ruc_check_hdr(struct qib_ibport *ibp, struct ib_header *hdr,
83 int has_grh, struct rvt_qp *qp, u32 bth0)
84 {
85 __be64 guid;
86 unsigned long flags;
87
88 if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
89 if (!has_grh) {
90 if (rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
91 IB_AH_GRH)
92 goto err;
93 } else {
94 const struct ib_global_route *grh;
95
96 if (!(rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
97 IB_AH_GRH))
98 goto err;
99 grh = rdma_ah_read_grh(&qp->alt_ah_attr);
100 guid = get_sguid(ibp, grh->sgid_index);
101 if (!gid_ok(&hdr->u.l.grh.dgid,
102 ibp->rvp.gid_prefix, guid))
103 goto err;
104 if (!gid_ok(&hdr->u.l.grh.sgid,
105 grh->dgid.global.subnet_prefix,
106 grh->dgid.global.interface_id))
107 goto err;
108 }
109 if (!qib_pkey_ok((u16)bth0,
110 qib_get_pkey(ibp, qp->s_alt_pkey_index))) {
111 qib_bad_pkey(ibp,
112 (u16)bth0,
113 (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
114 0, qp->ibqp.qp_num,
115 hdr->lrh[3], hdr->lrh[1]);
116 goto err;
117 }
118 /* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
119 if ((be16_to_cpu(hdr->lrh[3]) !=
120 rdma_ah_get_dlid(&qp->alt_ah_attr)) ||
121 ppd_from_ibp(ibp)->port !=
122 rdma_ah_get_port_num(&qp->alt_ah_attr))
123 goto err;
124 spin_lock_irqsave(&qp->s_lock, flags);
125 qib_migrate_qp(qp);
126 spin_unlock_irqrestore(&qp->s_lock, flags);
127 } else {
128 if (!has_grh) {
129 if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
130 IB_AH_GRH)
131 goto err;
132 } else {
133 const struct ib_global_route *grh;
134
135 if (!(rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
136 IB_AH_GRH))
137 goto err;
138 grh = rdma_ah_read_grh(&qp->remote_ah_attr);
139 guid = get_sguid(ibp, grh->sgid_index);
140 if (!gid_ok(&hdr->u.l.grh.dgid,
141 ibp->rvp.gid_prefix, guid))
142 goto err;
143 if (!gid_ok(&hdr->u.l.grh.sgid,
144 grh->dgid.global.subnet_prefix,
145 grh->dgid.global.interface_id))
146 goto err;
147 }
148 if (!qib_pkey_ok((u16)bth0,
149 qib_get_pkey(ibp, qp->s_pkey_index))) {
150 qib_bad_pkey(ibp,
151 (u16)bth0,
152 (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
153 0, qp->ibqp.qp_num,
154 hdr->lrh[3], hdr->lrh[1]);
155 goto err;
156 }
157 /* Validate the SLID. See Ch. 9.6.1.5 */
158 if (be16_to_cpu(hdr->lrh[3]) !=
159 rdma_ah_get_dlid(&qp->remote_ah_attr) ||
160 ppd_from_ibp(ibp)->port != qp->port_num)
161 goto err;
162 if (qp->s_mig_state == IB_MIG_REARM &&
163 !(bth0 & IB_BTH_MIG_REQ))
164 qp->s_mig_state = IB_MIG_ARMED;
165 }
166
167 return 0;
168
169 err:
170 return 1;
171 }
172
173 /**
174 * qib_ruc_loopback - handle UC and RC lookback requests
175 * @sqp: the sending QP
176 *
177 * This is called from qib_do_send() to
178 * forward a WQE addressed to the same HCA.
179 * Note that although we are single threaded due to the tasklet, we still
180 * have to protect against post_send(). We don't have to worry about
181 * receive interrupts since this is a connected protocol and all packets
182 * will pass through here.
183 */
qib_ruc_loopback(struct rvt_qp * sqp)184 static void qib_ruc_loopback(struct rvt_qp *sqp)
185 {
186 struct qib_ibport *ibp = to_iport(sqp->ibqp.device, sqp->port_num);
187 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
188 struct qib_devdata *dd = ppd->dd;
189 struct rvt_dev_info *rdi = &dd->verbs_dev.rdi;
190 struct rvt_qp *qp;
191 struct rvt_swqe *wqe;
192 struct rvt_sge *sge;
193 unsigned long flags;
194 struct ib_wc wc;
195 u64 sdata;
196 atomic64_t *maddr;
197 enum ib_wc_status send_status;
198 int release;
199 int ret;
200
201 rcu_read_lock();
202 /*
203 * Note that we check the responder QP state after
204 * checking the requester's state.
205 */
206 qp = rvt_lookup_qpn(rdi, &ibp->rvp, sqp->remote_qpn);
207 if (!qp)
208 goto done;
209
210 spin_lock_irqsave(&sqp->s_lock, flags);
211
212 /* Return if we are already busy processing a work request. */
213 if ((sqp->s_flags & (RVT_S_BUSY | RVT_S_ANY_WAIT)) ||
214 !(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_OR_FLUSH_SEND))
215 goto unlock;
216
217 sqp->s_flags |= RVT_S_BUSY;
218
219 again:
220 if (sqp->s_last == READ_ONCE(sqp->s_head))
221 goto clr_busy;
222 wqe = rvt_get_swqe_ptr(sqp, sqp->s_last);
223
224 /* Return if it is not OK to start a new work reqeust. */
225 if (!(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_NEXT_SEND_OK)) {
226 if (!(ib_rvt_state_ops[sqp->state] & RVT_FLUSH_SEND))
227 goto clr_busy;
228 /* We are in the error state, flush the work request. */
229 send_status = IB_WC_WR_FLUSH_ERR;
230 goto flush_send;
231 }
232
233 /*
234 * We can rely on the entry not changing without the s_lock
235 * being held until we update s_last.
236 * We increment s_cur to indicate s_last is in progress.
237 */
238 if (sqp->s_last == sqp->s_cur) {
239 if (++sqp->s_cur >= sqp->s_size)
240 sqp->s_cur = 0;
241 }
242 spin_unlock_irqrestore(&sqp->s_lock, flags);
243
244 if (!qp || !(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) ||
245 qp->ibqp.qp_type != sqp->ibqp.qp_type) {
246 ibp->rvp.n_pkt_drops++;
247 /*
248 * For RC, the requester would timeout and retry so
249 * shortcut the timeouts and just signal too many retries.
250 */
251 if (sqp->ibqp.qp_type == IB_QPT_RC)
252 send_status = IB_WC_RETRY_EXC_ERR;
253 else
254 send_status = IB_WC_SUCCESS;
255 goto serr;
256 }
257
258 memset(&wc, 0, sizeof(wc));
259 send_status = IB_WC_SUCCESS;
260
261 release = 1;
262 sqp->s_sge.sge = wqe->sg_list[0];
263 sqp->s_sge.sg_list = wqe->sg_list + 1;
264 sqp->s_sge.num_sge = wqe->wr.num_sge;
265 sqp->s_len = wqe->length;
266 switch (wqe->wr.opcode) {
267 case IB_WR_SEND_WITH_IMM:
268 wc.wc_flags = IB_WC_WITH_IMM;
269 wc.ex.imm_data = wqe->wr.ex.imm_data;
270 /* FALLTHROUGH */
271 case IB_WR_SEND:
272 ret = rvt_get_rwqe(qp, false);
273 if (ret < 0)
274 goto op_err;
275 if (!ret)
276 goto rnr_nak;
277 break;
278
279 case IB_WR_RDMA_WRITE_WITH_IMM:
280 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
281 goto inv_err;
282 wc.wc_flags = IB_WC_WITH_IMM;
283 wc.ex.imm_data = wqe->wr.ex.imm_data;
284 ret = rvt_get_rwqe(qp, true);
285 if (ret < 0)
286 goto op_err;
287 if (!ret)
288 goto rnr_nak;
289 /* FALLTHROUGH */
290 case IB_WR_RDMA_WRITE:
291 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
292 goto inv_err;
293 if (wqe->length == 0)
294 break;
295 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
296 wqe->rdma_wr.remote_addr,
297 wqe->rdma_wr.rkey,
298 IB_ACCESS_REMOTE_WRITE)))
299 goto acc_err;
300 qp->r_sge.sg_list = NULL;
301 qp->r_sge.num_sge = 1;
302 qp->r_sge.total_len = wqe->length;
303 break;
304
305 case IB_WR_RDMA_READ:
306 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
307 goto inv_err;
308 if (unlikely(!rvt_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
309 wqe->rdma_wr.remote_addr,
310 wqe->rdma_wr.rkey,
311 IB_ACCESS_REMOTE_READ)))
312 goto acc_err;
313 release = 0;
314 sqp->s_sge.sg_list = NULL;
315 sqp->s_sge.num_sge = 1;
316 qp->r_sge.sge = wqe->sg_list[0];
317 qp->r_sge.sg_list = wqe->sg_list + 1;
318 qp->r_sge.num_sge = wqe->wr.num_sge;
319 qp->r_sge.total_len = wqe->length;
320 break;
321
322 case IB_WR_ATOMIC_CMP_AND_SWP:
323 case IB_WR_ATOMIC_FETCH_AND_ADD:
324 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
325 goto inv_err;
326 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
327 wqe->atomic_wr.remote_addr,
328 wqe->atomic_wr.rkey,
329 IB_ACCESS_REMOTE_ATOMIC)))
330 goto acc_err;
331 /* Perform atomic OP and save result. */
332 maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
333 sdata = wqe->atomic_wr.compare_add;
334 *(u64 *) sqp->s_sge.sge.vaddr =
335 (wqe->atomic_wr.wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
336 (u64) atomic64_add_return(sdata, maddr) - sdata :
337 (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
338 sdata, wqe->atomic_wr.swap);
339 rvt_put_mr(qp->r_sge.sge.mr);
340 qp->r_sge.num_sge = 0;
341 goto send_comp;
342
343 default:
344 send_status = IB_WC_LOC_QP_OP_ERR;
345 goto serr;
346 }
347
348 sge = &sqp->s_sge.sge;
349 while (sqp->s_len) {
350 u32 len = sqp->s_len;
351
352 if (len > sge->length)
353 len = sge->length;
354 if (len > sge->sge_length)
355 len = sge->sge_length;
356 BUG_ON(len == 0);
357 qib_copy_sge(&qp->r_sge, sge->vaddr, len, release);
358 sge->vaddr += len;
359 sge->length -= len;
360 sge->sge_length -= len;
361 if (sge->sge_length == 0) {
362 if (!release)
363 rvt_put_mr(sge->mr);
364 if (--sqp->s_sge.num_sge)
365 *sge = *sqp->s_sge.sg_list++;
366 } else if (sge->length == 0 && sge->mr->lkey) {
367 if (++sge->n >= RVT_SEGSZ) {
368 if (++sge->m >= sge->mr->mapsz)
369 break;
370 sge->n = 0;
371 }
372 sge->vaddr =
373 sge->mr->map[sge->m]->segs[sge->n].vaddr;
374 sge->length =
375 sge->mr->map[sge->m]->segs[sge->n].length;
376 }
377 sqp->s_len -= len;
378 }
379 if (release)
380 rvt_put_ss(&qp->r_sge);
381
382 if (!test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
383 goto send_comp;
384
385 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
386 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
387 else
388 wc.opcode = IB_WC_RECV;
389 wc.wr_id = qp->r_wr_id;
390 wc.status = IB_WC_SUCCESS;
391 wc.byte_len = wqe->length;
392 wc.qp = &qp->ibqp;
393 wc.src_qp = qp->remote_qpn;
394 wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr);
395 wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
396 wc.port_num = 1;
397 /* Signal completion event if the solicited bit is set. */
398 rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
399 wqe->wr.send_flags & IB_SEND_SOLICITED);
400
401 send_comp:
402 spin_lock_irqsave(&sqp->s_lock, flags);
403 ibp->rvp.n_loop_pkts++;
404 flush_send:
405 sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
406 qib_send_complete(sqp, wqe, send_status);
407 goto again;
408
409 rnr_nak:
410 /* Handle RNR NAK */
411 if (qp->ibqp.qp_type == IB_QPT_UC)
412 goto send_comp;
413 ibp->rvp.n_rnr_naks++;
414 /*
415 * Note: we don't need the s_lock held since the BUSY flag
416 * makes this single threaded.
417 */
418 if (sqp->s_rnr_retry == 0) {
419 send_status = IB_WC_RNR_RETRY_EXC_ERR;
420 goto serr;
421 }
422 if (sqp->s_rnr_retry_cnt < 7)
423 sqp->s_rnr_retry--;
424 spin_lock_irqsave(&sqp->s_lock, flags);
425 if (!(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_RECV_OK))
426 goto clr_busy;
427 rvt_add_rnr_timer(sqp, qp->r_min_rnr_timer <<
428 IB_AETH_CREDIT_SHIFT);
429 goto clr_busy;
430
431 op_err:
432 send_status = IB_WC_REM_OP_ERR;
433 wc.status = IB_WC_LOC_QP_OP_ERR;
434 goto err;
435
436 inv_err:
437 send_status = IB_WC_REM_INV_REQ_ERR;
438 wc.status = IB_WC_LOC_QP_OP_ERR;
439 goto err;
440
441 acc_err:
442 send_status = IB_WC_REM_ACCESS_ERR;
443 wc.status = IB_WC_LOC_PROT_ERR;
444 err:
445 /* responder goes to error state */
446 rvt_rc_error(qp, wc.status);
447
448 serr:
449 spin_lock_irqsave(&sqp->s_lock, flags);
450 qib_send_complete(sqp, wqe, send_status);
451 if (sqp->ibqp.qp_type == IB_QPT_RC) {
452 int lastwqe = rvt_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
453
454 sqp->s_flags &= ~RVT_S_BUSY;
455 spin_unlock_irqrestore(&sqp->s_lock, flags);
456 if (lastwqe) {
457 struct ib_event ev;
458
459 ev.device = sqp->ibqp.device;
460 ev.element.qp = &sqp->ibqp;
461 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
462 sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
463 }
464 goto done;
465 }
466 clr_busy:
467 sqp->s_flags &= ~RVT_S_BUSY;
468 unlock:
469 spin_unlock_irqrestore(&sqp->s_lock, flags);
470 done:
471 rcu_read_unlock();
472 }
473
474 /**
475 * qib_make_grh - construct a GRH header
476 * @ibp: a pointer to the IB port
477 * @hdr: a pointer to the GRH header being constructed
478 * @grh: the global route address to send to
479 * @hwords: the number of 32 bit words of header being sent
480 * @nwords: the number of 32 bit words of data being sent
481 *
482 * Return the size of the header in 32 bit words.
483 */
qib_make_grh(struct qib_ibport * ibp,struct ib_grh * hdr,const struct ib_global_route * grh,u32 hwords,u32 nwords)484 u32 qib_make_grh(struct qib_ibport *ibp, struct ib_grh *hdr,
485 const struct ib_global_route *grh, u32 hwords, u32 nwords)
486 {
487 hdr->version_tclass_flow =
488 cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
489 (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
490 (grh->flow_label << IB_GRH_FLOW_SHIFT));
491 hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
492 /* next_hdr is defined by C8-7 in ch. 8.4.1 */
493 hdr->next_hdr = IB_GRH_NEXT_HDR;
494 hdr->hop_limit = grh->hop_limit;
495 /* The SGID is 32-bit aligned. */
496 hdr->sgid.global.subnet_prefix = ibp->rvp.gid_prefix;
497 if (!grh->sgid_index)
498 hdr->sgid.global.interface_id = ppd_from_ibp(ibp)->guid;
499 else if (grh->sgid_index < QIB_GUIDS_PER_PORT)
500 hdr->sgid.global.interface_id = ibp->guids[grh->sgid_index - 1];
501 hdr->dgid = grh->dgid;
502
503 /* GRH header size in 32-bit words. */
504 return sizeof(struct ib_grh) / sizeof(u32);
505 }
506
qib_make_ruc_header(struct rvt_qp * qp,struct ib_other_headers * ohdr,u32 bth0,u32 bth2)507 void qib_make_ruc_header(struct rvt_qp *qp, struct ib_other_headers *ohdr,
508 u32 bth0, u32 bth2)
509 {
510 struct qib_qp_priv *priv = qp->priv;
511 struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
512 u16 lrh0;
513 u32 nwords;
514 u32 extra_bytes;
515
516 /* Construct the header. */
517 extra_bytes = -qp->s_cur_size & 3;
518 nwords = (qp->s_cur_size + extra_bytes) >> 2;
519 lrh0 = QIB_LRH_BTH;
520 if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
521 qp->s_hdrwords +=
522 qib_make_grh(ibp, &priv->s_hdr->u.l.grh,
523 rdma_ah_read_grh(&qp->remote_ah_attr),
524 qp->s_hdrwords, nwords);
525 lrh0 = QIB_LRH_GRH;
526 }
527 lrh0 |= ibp->sl_to_vl[rdma_ah_get_sl(&qp->remote_ah_attr)] << 12 |
528 rdma_ah_get_sl(&qp->remote_ah_attr) << 4;
529 priv->s_hdr->lrh[0] = cpu_to_be16(lrh0);
530 priv->s_hdr->lrh[1] =
531 cpu_to_be16(rdma_ah_get_dlid(&qp->remote_ah_attr));
532 priv->s_hdr->lrh[2] =
533 cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
534 priv->s_hdr->lrh[3] =
535 cpu_to_be16(ppd_from_ibp(ibp)->lid |
536 rdma_ah_get_path_bits(&qp->remote_ah_attr));
537 bth0 |= qib_get_pkey(ibp, qp->s_pkey_index);
538 bth0 |= extra_bytes << 20;
539 if (qp->s_mig_state == IB_MIG_MIGRATED)
540 bth0 |= IB_BTH_MIG_REQ;
541 ohdr->bth[0] = cpu_to_be32(bth0);
542 ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
543 ohdr->bth[2] = cpu_to_be32(bth2);
544 this_cpu_inc(ibp->pmastats->n_unicast_xmit);
545 }
546
_qib_do_send(struct work_struct * work)547 void _qib_do_send(struct work_struct *work)
548 {
549 struct qib_qp_priv *priv = container_of(work, struct qib_qp_priv,
550 s_work);
551 struct rvt_qp *qp = priv->owner;
552
553 qib_do_send(qp);
554 }
555
556 /**
557 * qib_do_send - perform a send on a QP
558 * @qp: pointer to the QP
559 *
560 * Process entries in the send work queue until credit or queue is
561 * exhausted. Only allow one CPU to send a packet per QP (tasklet).
562 * Otherwise, two threads could send packets out of order.
563 */
qib_do_send(struct rvt_qp * qp)564 void qib_do_send(struct rvt_qp *qp)
565 {
566 struct qib_qp_priv *priv = qp->priv;
567 struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
568 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
569 int (*make_req)(struct rvt_qp *qp, unsigned long *flags);
570 unsigned long flags;
571
572 if ((qp->ibqp.qp_type == IB_QPT_RC ||
573 qp->ibqp.qp_type == IB_QPT_UC) &&
574 (rdma_ah_get_dlid(&qp->remote_ah_attr) &
575 ~((1 << ppd->lmc) - 1)) == ppd->lid) {
576 qib_ruc_loopback(qp);
577 return;
578 }
579
580 if (qp->ibqp.qp_type == IB_QPT_RC)
581 make_req = qib_make_rc_req;
582 else if (qp->ibqp.qp_type == IB_QPT_UC)
583 make_req = qib_make_uc_req;
584 else
585 make_req = qib_make_ud_req;
586
587 spin_lock_irqsave(&qp->s_lock, flags);
588
589 /* Return if we are already busy processing a work request. */
590 if (!qib_send_ok(qp)) {
591 spin_unlock_irqrestore(&qp->s_lock, flags);
592 return;
593 }
594
595 qp->s_flags |= RVT_S_BUSY;
596
597 do {
598 /* Check for a constructed packet to be sent. */
599 if (qp->s_hdrwords != 0) {
600 spin_unlock_irqrestore(&qp->s_lock, flags);
601 /*
602 * If the packet cannot be sent now, return and
603 * the send tasklet will be woken up later.
604 */
605 if (qib_verbs_send(qp, priv->s_hdr, qp->s_hdrwords,
606 qp->s_cur_sge, qp->s_cur_size))
607 return;
608 /* Record that s_hdr is empty. */
609 qp->s_hdrwords = 0;
610 spin_lock_irqsave(&qp->s_lock, flags);
611 }
612 } while (make_req(qp, &flags));
613
614 spin_unlock_irqrestore(&qp->s_lock, flags);
615 }
616
617 /*
618 * This should be called with s_lock held.
619 */
qib_send_complete(struct rvt_qp * qp,struct rvt_swqe * wqe,enum ib_wc_status status)620 void qib_send_complete(struct rvt_qp *qp, struct rvt_swqe *wqe,
621 enum ib_wc_status status)
622 {
623 u32 old_last, last;
624
625 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_OR_FLUSH_SEND))
626 return;
627
628 last = qp->s_last;
629 old_last = last;
630 if (++last >= qp->s_size)
631 last = 0;
632 qp->s_last = last;
633 /* See post_send() */
634 barrier();
635 rvt_put_swqe(wqe);
636 if (qp->ibqp.qp_type == IB_QPT_UD ||
637 qp->ibqp.qp_type == IB_QPT_SMI ||
638 qp->ibqp.qp_type == IB_QPT_GSI)
639 atomic_dec(&ibah_to_rvtah(wqe->ud_wr.ah)->refcount);
640
641 rvt_qp_swqe_complete(qp,
642 wqe,
643 ib_qib_wc_opcode[wqe->wr.opcode],
644 status);
645
646 if (qp->s_acked == old_last)
647 qp->s_acked = last;
648 if (qp->s_cur == old_last)
649 qp->s_cur = last;
650 if (qp->s_tail == old_last)
651 qp->s_tail = last;
652 if (qp->state == IB_QPS_SQD && last == qp->s_cur)
653 qp->s_draining = 0;
654 }
655
