Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / drivers / infiniband / hw / ipath / ipath_ruc.c
blob1f95bbaf7602289c79854a2919f966cce35e618a
1 /*
2 * Copyright (c) 2006, 2007, 2008 QLogic Corporation. All rights reserved.
3 * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
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:
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
13 * conditions are met:
15 * - Redistributions of source code must retain the above
16 * copyright notice, this list of conditions and the following
17 * disclaimer.
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.
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.
34 #include <linux/sched.h>
35 #include <linux/spinlock.h>
37 #include "ipath_verbs.h"
38 #include "ipath_kernel.h"
41 * Convert the AETH RNR timeout code into the number of milliseconds.
43 const u32 ib_ipath_rnr_table[32] = {
44 656, /* 0 */
45 1, /* 1 */
46 1, /* 2 */
47 1, /* 3 */
48 1, /* 4 */
49 1, /* 5 */
50 1, /* 6 */
51 1, /* 7 */
52 1, /* 8 */
53 1, /* 9 */
54 1, /* A */
55 1, /* B */
56 1, /* C */
57 1, /* D */
58 2, /* E */
59 2, /* F */
60 3, /* 10 */
61 4, /* 11 */
62 6, /* 12 */
63 8, /* 13 */
64 11, /* 14 */
65 16, /* 15 */
66 21, /* 16 */
67 31, /* 17 */
68 41, /* 18 */
69 62, /* 19 */
70 82, /* 1A */
71 123, /* 1B */
72 164, /* 1C */
73 246, /* 1D */
74 328, /* 1E */
75 492 /* 1F */
78 /**
79 * ipath_insert_rnr_queue - put QP on the RNR timeout list for the device
80 * @qp: the QP
82 * Called with the QP s_lock held and interrupts disabled.
83 * XXX Use a simple list for now. We might need a priority
84 * queue if we have lots of QPs waiting for RNR timeouts
85 * but that should be rare.
87 void ipath_insert_rnr_queue(struct ipath_qp *qp)
89 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
91 /* We already did a spin_lock_irqsave(), so just use spin_lock */
92 spin_lock(&dev->pending_lock);
93 if (list_empty(&dev->rnrwait))
94 list_add(&qp->timerwait, &dev->rnrwait);
95 else {
96 struct list_head *l = &dev->rnrwait;
97 struct ipath_qp *nqp = list_entry(l->next, struct ipath_qp,
98 timerwait);
100 while (qp->s_rnr_timeout >= nqp->s_rnr_timeout) {
101 qp->s_rnr_timeout -= nqp->s_rnr_timeout;
102 l = l->next;
103 if (l->next == &dev->rnrwait) {
104 nqp = NULL;
105 break;
107 nqp = list_entry(l->next, struct ipath_qp,
108 timerwait);
110 if (nqp)
111 nqp->s_rnr_timeout -= qp->s_rnr_timeout;
112 list_add(&qp->timerwait, l);
114 spin_unlock(&dev->pending_lock);
118 * ipath_init_sge - Validate a RWQE and fill in the SGE state
119 * @qp: the QP
121 * Return 1 if OK.
123 int ipath_init_sge(struct ipath_qp *qp, struct ipath_rwqe *wqe,
124 u32 *lengthp, struct ipath_sge_state *ss)
126 int i, j, ret;
127 struct ib_wc wc;
129 *lengthp = 0;
130 for (i = j = 0; i < wqe->num_sge; i++) {
131 if (wqe->sg_list[i].length == 0)
132 continue;
133 /* Check LKEY */
134 if (!ipath_lkey_ok(qp, j ? &ss->sg_list[j - 1] : &ss->sge,
135 &wqe->sg_list[i], IB_ACCESS_LOCAL_WRITE))
136 goto bad_lkey;
137 *lengthp += wqe->sg_list[i].length;
138 j++;
140 ss->num_sge = j;
141 ret = 1;
142 goto bail;
144 bad_lkey:
145 memset(&wc, 0, sizeof(wc));
146 wc.wr_id = wqe->wr_id;
147 wc.status = IB_WC_LOC_PROT_ERR;
148 wc.opcode = IB_WC_RECV;
149 wc.qp = &qp->ibqp;
150 /* Signal solicited completion event. */
151 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
152 ret = 0;
153 bail:
154 return ret;
158 * ipath_get_rwqe - copy the next RWQE into the QP's RWQE
159 * @qp: the QP
160 * @wr_id_only: update qp->r_wr_id only, not qp->r_sge
162 * Return 0 if no RWQE is available, otherwise return 1.
164 * Can be called from interrupt level.
166 int ipath_get_rwqe(struct ipath_qp *qp, int wr_id_only)
168 unsigned long flags;
169 struct ipath_rq *rq;
170 struct ipath_rwq *wq;
171 struct ipath_srq *srq;
172 struct ipath_rwqe *wqe;
173 void (*handler)(struct ib_event *, void *);
174 u32 tail;
175 int ret;
177 if (qp->ibqp.srq) {
178 srq = to_isrq(qp->ibqp.srq);
179 handler = srq->ibsrq.event_handler;
180 rq = &srq->rq;
181 } else {
182 srq = NULL;
183 handler = NULL;
184 rq = &qp->r_rq;
187 spin_lock_irqsave(&rq->lock, flags);
188 if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_RECV_OK)) {
189 ret = 0;
190 goto unlock;
193 wq = rq->wq;
194 tail = wq->tail;
195 /* Validate tail before using it since it is user writable. */
196 if (tail >= rq->size)
197 tail = 0;
198 do {
199 if (unlikely(tail == wq->head)) {
200 ret = 0;
201 goto unlock;
203 /* Make sure entry is read after head index is read. */
204 smp_rmb();
205 wqe = get_rwqe_ptr(rq, tail);
206 if (++tail >= rq->size)
207 tail = 0;
208 if (wr_id_only)
209 break;
210 qp->r_sge.sg_list = qp->r_sg_list;
211 } while (!ipath_init_sge(qp, wqe, &qp->r_len, &qp->r_sge));
212 qp->r_wr_id = wqe->wr_id;
213 wq->tail = tail;
215 ret = 1;
216 set_bit(IPATH_R_WRID_VALID, &qp->r_aflags);
217 if (handler) {
218 u32 n;
221 * validate head pointer value and compute
222 * the number of remaining WQEs.
224 n = wq->head;
225 if (n >= rq->size)
226 n = 0;
227 if (n < tail)
228 n += rq->size - tail;
229 else
230 n -= tail;
231 if (n < srq->limit) {
232 struct ib_event ev;
234 srq->limit = 0;
235 spin_unlock_irqrestore(&rq->lock, flags);
236 ev.device = qp->ibqp.device;
237 ev.element.srq = qp->ibqp.srq;
238 ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
239 handler(&ev, srq->ibsrq.srq_context);
240 goto bail;
243 unlock:
244 spin_unlock_irqrestore(&rq->lock, flags);
245 bail:
246 return ret;
250 * ipath_ruc_loopback - handle UC and RC lookback requests
251 * @sqp: the sending QP
253 * This is called from ipath_do_send() to
254 * forward a WQE addressed to the same HCA.
255 * Note that although we are single threaded due to the tasklet, we still
256 * have to protect against post_send(). We don't have to worry about
257 * receive interrupts since this is a connected protocol and all packets
258 * will pass through here.
260 static void ipath_ruc_loopback(struct ipath_qp *sqp)
262 struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
263 struct ipath_qp *qp;
264 struct ipath_swqe *wqe;
265 struct ipath_sge *sge;
266 unsigned long flags;
267 struct ib_wc wc;
268 u64 sdata;
269 atomic64_t *maddr;
270 enum ib_wc_status send_status;
273 * Note that we check the responder QP state after
274 * checking the requester's state.
276 qp = ipath_lookup_qpn(&dev->qp_table, sqp->remote_qpn);
278 spin_lock_irqsave(&sqp->s_lock, flags);
280 /* Return if we are already busy processing a work request. */
281 if ((sqp->s_flags & (IPATH_S_BUSY | IPATH_S_ANY_WAIT)) ||
282 !(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_OR_FLUSH_SEND))
283 goto unlock;
285 sqp->s_flags |= IPATH_S_BUSY;
287 again:
288 if (sqp->s_last == sqp->s_head)
289 goto clr_busy;
290 wqe = get_swqe_ptr(sqp, sqp->s_last);
292 /* Return if it is not OK to start a new work reqeust. */
293 if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_NEXT_SEND_OK)) {
294 if (!(ib_ipath_state_ops[sqp->state] & IPATH_FLUSH_SEND))
295 goto clr_busy;
296 /* We are in the error state, flush the work request. */
297 send_status = IB_WC_WR_FLUSH_ERR;
298 goto flush_send;
302 * We can rely on the entry not changing without the s_lock
303 * being held until we update s_last.
304 * We increment s_cur to indicate s_last is in progress.
306 if (sqp->s_last == sqp->s_cur) {
307 if (++sqp->s_cur >= sqp->s_size)
308 sqp->s_cur = 0;
310 spin_unlock_irqrestore(&sqp->s_lock, flags);
312 if (!qp || !(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_RECV_OK)) {
313 dev->n_pkt_drops++;
315 * For RC, the requester would timeout and retry so
316 * shortcut the timeouts and just signal too many retries.
318 if (sqp->ibqp.qp_type == IB_QPT_RC)
319 send_status = IB_WC_RETRY_EXC_ERR;
320 else
321 send_status = IB_WC_SUCCESS;
322 goto serr;
325 memset(&wc, 0, sizeof wc);
326 send_status = IB_WC_SUCCESS;
328 sqp->s_sge.sge = wqe->sg_list[0];
329 sqp->s_sge.sg_list = wqe->sg_list + 1;
330 sqp->s_sge.num_sge = wqe->wr.num_sge;
331 sqp->s_len = wqe->length;
332 switch (wqe->wr.opcode) {
333 case IB_WR_SEND_WITH_IMM:
334 wc.wc_flags = IB_WC_WITH_IMM;
335 wc.ex.imm_data = wqe->wr.ex.imm_data;
336 /* FALLTHROUGH */
337 case IB_WR_SEND:
338 if (!ipath_get_rwqe(qp, 0))
339 goto rnr_nak;
340 break;
342 case IB_WR_RDMA_WRITE_WITH_IMM:
343 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
344 goto inv_err;
345 wc.wc_flags = IB_WC_WITH_IMM;
346 wc.ex.imm_data = wqe->wr.ex.imm_data;
347 if (!ipath_get_rwqe(qp, 1))
348 goto rnr_nak;
349 /* FALLTHROUGH */
350 case IB_WR_RDMA_WRITE:
351 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
352 goto inv_err;
353 if (wqe->length == 0)
354 break;
355 if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, wqe->length,
356 wqe->wr.wr.rdma.remote_addr,
357 wqe->wr.wr.rdma.rkey,
358 IB_ACCESS_REMOTE_WRITE)))
359 goto acc_err;
360 break;
362 case IB_WR_RDMA_READ:
363 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
364 goto inv_err;
365 if (unlikely(!ipath_rkey_ok(qp, &sqp->s_sge, wqe->length,
366 wqe->wr.wr.rdma.remote_addr,
367 wqe->wr.wr.rdma.rkey,
368 IB_ACCESS_REMOTE_READ)))
369 goto acc_err;
370 qp->r_sge.sge = wqe->sg_list[0];
371 qp->r_sge.sg_list = wqe->sg_list + 1;
372 qp->r_sge.num_sge = wqe->wr.num_sge;
373 break;
375 case IB_WR_ATOMIC_CMP_AND_SWP:
376 case IB_WR_ATOMIC_FETCH_AND_ADD:
377 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
378 goto inv_err;
379 if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, sizeof(u64),
380 wqe->wr.wr.atomic.remote_addr,
381 wqe->wr.wr.atomic.rkey,
382 IB_ACCESS_REMOTE_ATOMIC)))
383 goto acc_err;
384 /* Perform atomic OP and save result. */
385 maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
386 sdata = wqe->wr.wr.atomic.compare_add;
387 *(u64 *) sqp->s_sge.sge.vaddr =
388 (wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
389 (u64) atomic64_add_return(sdata, maddr) - sdata :
390 (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
391 sdata, wqe->wr.wr.atomic.swap);
392 goto send_comp;
394 default:
395 send_status = IB_WC_LOC_QP_OP_ERR;
396 goto serr;
399 sge = &sqp->s_sge.sge;
400 while (sqp->s_len) {
401 u32 len = sqp->s_len;
403 if (len > sge->length)
404 len = sge->length;
405 if (len > sge->sge_length)
406 len = sge->sge_length;
407 BUG_ON(len == 0);
408 ipath_copy_sge(&qp->r_sge, sge->vaddr, len);
409 sge->vaddr += len;
410 sge->length -= len;
411 sge->sge_length -= len;
412 if (sge->sge_length == 0) {
413 if (--sqp->s_sge.num_sge)
414 *sge = *sqp->s_sge.sg_list++;
415 } else if (sge->length == 0 && sge->mr != NULL) {
416 if (++sge->n >= IPATH_SEGSZ) {
417 if (++sge->m >= sge->mr->mapsz)
418 break;
419 sge->n = 0;
421 sge->vaddr =
422 sge->mr->map[sge->m]->segs[sge->n].vaddr;
423 sge->length =
424 sge->mr->map[sge->m]->segs[sge->n].length;
426 sqp->s_len -= len;
429 if (!test_and_clear_bit(IPATH_R_WRID_VALID, &qp->r_aflags))
430 goto send_comp;
432 if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
433 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
434 else
435 wc.opcode = IB_WC_RECV;
436 wc.wr_id = qp->r_wr_id;
437 wc.status = IB_WC_SUCCESS;
438 wc.byte_len = wqe->length;
439 wc.qp = &qp->ibqp;
440 wc.src_qp = qp->remote_qpn;
441 wc.slid = qp->remote_ah_attr.dlid;
442 wc.sl = qp->remote_ah_attr.sl;
443 wc.port_num = 1;
444 /* Signal completion event if the solicited bit is set. */
445 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
446 wqe->wr.send_flags & IB_SEND_SOLICITED);
448 send_comp:
449 spin_lock_irqsave(&sqp->s_lock, flags);
450 flush_send:
451 sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
452 ipath_send_complete(sqp, wqe, send_status);
453 goto again;
455 rnr_nak:
456 /* Handle RNR NAK */
457 if (qp->ibqp.qp_type == IB_QPT_UC)
458 goto send_comp;
460 * Note: we don't need the s_lock held since the BUSY flag
461 * makes this single threaded.
463 if (sqp->s_rnr_retry == 0) {
464 send_status = IB_WC_RNR_RETRY_EXC_ERR;
465 goto serr;
467 if (sqp->s_rnr_retry_cnt < 7)
468 sqp->s_rnr_retry--;
469 spin_lock_irqsave(&sqp->s_lock, flags);
470 if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_RECV_OK))
471 goto clr_busy;
472 sqp->s_flags |= IPATH_S_WAITING;
473 dev->n_rnr_naks++;
474 sqp->s_rnr_timeout = ib_ipath_rnr_table[qp->r_min_rnr_timer];
475 ipath_insert_rnr_queue(sqp);
476 goto clr_busy;
478 inv_err:
479 send_status = IB_WC_REM_INV_REQ_ERR;
480 wc.status = IB_WC_LOC_QP_OP_ERR;
481 goto err;
483 acc_err:
484 send_status = IB_WC_REM_ACCESS_ERR;
485 wc.status = IB_WC_LOC_PROT_ERR;
486 err:
487 /* responder goes to error state */
488 ipath_rc_error(qp, wc.status);
490 serr:
491 spin_lock_irqsave(&sqp->s_lock, flags);
492 ipath_send_complete(sqp, wqe, send_status);
493 if (sqp->ibqp.qp_type == IB_QPT_RC) {
494 int lastwqe = ipath_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
496 sqp->s_flags &= ~IPATH_S_BUSY;
497 spin_unlock_irqrestore(&sqp->s_lock, flags);
498 if (lastwqe) {
499 struct ib_event ev;
501 ev.device = sqp->ibqp.device;
502 ev.element.qp = &sqp->ibqp;
503 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
504 sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
506 goto done;
508 clr_busy:
509 sqp->s_flags &= ~IPATH_S_BUSY;
510 unlock:
511 spin_unlock_irqrestore(&sqp->s_lock, flags);
512 done:
513 if (qp && atomic_dec_and_test(&qp->refcount))
514 wake_up(&qp->wait);
517 static void want_buffer(struct ipath_devdata *dd, struct ipath_qp *qp)
519 if (!(dd->ipath_flags & IPATH_HAS_SEND_DMA) ||
520 qp->ibqp.qp_type == IB_QPT_SMI) {
521 unsigned long flags;
523 spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
524 dd->ipath_sendctrl |= INFINIPATH_S_PIOINTBUFAVAIL;
525 ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
526 dd->ipath_sendctrl);
527 ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
528 spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
533 * ipath_no_bufs_available - tell the layer driver we need buffers
534 * @qp: the QP that caused the problem
535 * @dev: the device we ran out of buffers on
537 * Called when we run out of PIO buffers.
538 * If we are now in the error state, return zero to flush the
539 * send work request.
541 static int ipath_no_bufs_available(struct ipath_qp *qp,
542 struct ipath_ibdev *dev)
544 unsigned long flags;
545 int ret = 1;
548 * Note that as soon as want_buffer() is called and
549 * possibly before it returns, ipath_ib_piobufavail()
550 * could be called. Therefore, put QP on the piowait list before
551 * enabling the PIO avail interrupt.
553 spin_lock_irqsave(&qp->s_lock, flags);
554 if (ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK) {
555 dev->n_piowait++;
556 qp->s_flags |= IPATH_S_WAITING;
557 qp->s_flags &= ~IPATH_S_BUSY;
558 spin_lock(&dev->pending_lock);
559 if (list_empty(&qp->piowait))
560 list_add_tail(&qp->piowait, &dev->piowait);
561 spin_unlock(&dev->pending_lock);
562 } else
563 ret = 0;
564 spin_unlock_irqrestore(&qp->s_lock, flags);
565 if (ret)
566 want_buffer(dev->dd, qp);
567 return ret;
571 * ipath_make_grh - construct a GRH header
572 * @dev: a pointer to the ipath device
573 * @hdr: a pointer to the GRH header being constructed
574 * @grh: the global route address to send to
575 * @hwords: the number of 32 bit words of header being sent
576 * @nwords: the number of 32 bit words of data being sent
578 * Return the size of the header in 32 bit words.
580 u32 ipath_make_grh(struct ipath_ibdev *dev, struct ib_grh *hdr,
581 struct ib_global_route *grh, u32 hwords, u32 nwords)
583 hdr->version_tclass_flow =
584 cpu_to_be32((6 << 28) |
585 (grh->traffic_class << 20) |
586 grh->flow_label);
587 hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
588 /* next_hdr is defined by C8-7 in ch. 8.4.1 */
589 hdr->next_hdr = 0x1B;
590 hdr->hop_limit = grh->hop_limit;
591 /* The SGID is 32-bit aligned. */
592 hdr->sgid.global.subnet_prefix = dev->gid_prefix;
593 hdr->sgid.global.interface_id = dev->dd->ipath_guid;
594 hdr->dgid = grh->dgid;
596 /* GRH header size in 32-bit words. */
597 return sizeof(struct ib_grh) / sizeof(u32);
600 void ipath_make_ruc_header(struct ipath_ibdev *dev, struct ipath_qp *qp,
601 struct ipath_other_headers *ohdr,
602 u32 bth0, u32 bth2)
604 u16 lrh0;
605 u32 nwords;
606 u32 extra_bytes;
608 /* Construct the header. */
609 extra_bytes = -qp->s_cur_size & 3;
610 nwords = (qp->s_cur_size + extra_bytes) >> 2;
611 lrh0 = IPATH_LRH_BTH;
612 if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
613 qp->s_hdrwords += ipath_make_grh(dev, &qp->s_hdr.u.l.grh,
614 &qp->remote_ah_attr.grh,
615 qp->s_hdrwords, nwords);
616 lrh0 = IPATH_LRH_GRH;
618 lrh0 |= qp->remote_ah_attr.sl << 4;
619 qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
620 qp->s_hdr.lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid);
621 qp->s_hdr.lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
622 qp->s_hdr.lrh[3] = cpu_to_be16(dev->dd->ipath_lid |
623 qp->remote_ah_attr.src_path_bits);
624 bth0 |= ipath_get_pkey(dev->dd, qp->s_pkey_index);
625 bth0 |= extra_bytes << 20;
626 ohdr->bth[0] = cpu_to_be32(bth0 | (1 << 22));
627 ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
628 ohdr->bth[2] = cpu_to_be32(bth2);
632 * ipath_do_send - perform a send on a QP
633 * @data: contains a pointer to the QP
635 * Process entries in the send work queue until credit or queue is
636 * exhausted. Only allow one CPU to send a packet per QP (tasklet).
637 * Otherwise, two threads could send packets out of order.
639 void ipath_do_send(unsigned long data)
641 struct ipath_qp *qp = (struct ipath_qp *)data;
642 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
643 int (*make_req)(struct ipath_qp *qp);
644 unsigned long flags;
646 if ((qp->ibqp.qp_type == IB_QPT_RC ||
647 qp->ibqp.qp_type == IB_QPT_UC) &&
648 qp->remote_ah_attr.dlid == dev->dd->ipath_lid) {
649 ipath_ruc_loopback(qp);
650 goto bail;
653 if (qp->ibqp.qp_type == IB_QPT_RC)
654 make_req = ipath_make_rc_req;
655 else if (qp->ibqp.qp_type == IB_QPT_UC)
656 make_req = ipath_make_uc_req;
657 else
658 make_req = ipath_make_ud_req;
660 spin_lock_irqsave(&qp->s_lock, flags);
662 /* Return if we are already busy processing a work request. */
663 if ((qp->s_flags & (IPATH_S_BUSY | IPATH_S_ANY_WAIT)) ||
664 !(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_OR_FLUSH_SEND)) {
665 spin_unlock_irqrestore(&qp->s_lock, flags);
666 goto bail;
669 qp->s_flags |= IPATH_S_BUSY;
671 spin_unlock_irqrestore(&qp->s_lock, flags);
673 again:
674 /* Check for a constructed packet to be sent. */
675 if (qp->s_hdrwords != 0) {
677 * If no PIO bufs are available, return. An interrupt will
678 * call ipath_ib_piobufavail() when one is available.
680 if (ipath_verbs_send(qp, &qp->s_hdr, qp->s_hdrwords,
681 qp->s_cur_sge, qp->s_cur_size)) {
682 if (ipath_no_bufs_available(qp, dev))
683 goto bail;
685 dev->n_unicast_xmit++;
686 /* Record that we sent the packet and s_hdr is empty. */
687 qp->s_hdrwords = 0;
690 if (make_req(qp))
691 goto again;
693 bail:;
697 * This should be called with s_lock held.
699 void ipath_send_complete(struct ipath_qp *qp, struct ipath_swqe *wqe,
700 enum ib_wc_status status)
702 u32 old_last, last;
704 if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_OR_FLUSH_SEND))
705 return;
707 /* See ch. 11.2.4.1 and 10.7.3.1 */
708 if (!(qp->s_flags & IPATH_S_SIGNAL_REQ_WR) ||
709 (wqe->wr.send_flags & IB_SEND_SIGNALED) ||
710 status != IB_WC_SUCCESS) {
711 struct ib_wc wc;
713 memset(&wc, 0, sizeof wc);
714 wc.wr_id = wqe->wr.wr_id;
715 wc.status = status;
716 wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
717 wc.qp = &qp->ibqp;
718 if (status == IB_WC_SUCCESS)
719 wc.byte_len = wqe->length;
720 ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc,
721 status != IB_WC_SUCCESS);
724 old_last = last = qp->s_last;
725 if (++last >= qp->s_size)
726 last = 0;
727 qp->s_last = last;
728 if (qp->s_cur == old_last)
729 qp->s_cur = last;
730 if (qp->s_tail == old_last)
731 qp->s_tail = last;
732 if (qp->state == IB_QPS_SQD && last == qp->s_cur)
733 qp->s_draining = 0;