1 /*
2 * Copyright (c) 2006, 2007, 2008 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/sched.h>
35 #include <rdma/ib_smi.h>
36
37 #include "ipath_verbs.h"
38 #include "ipath_kernel.h"
39
40 /**
41 * ipath_ud_loopback - handle send on loopback QPs
42 * @sqp: the sending QP
43 * @swqe: the send work request
44 *
45 * This is called from ipath_make_ud_req() to forward a WQE addressed
46 * to the same HCA.
47 * Note that the receive interrupt handler may be calling ipath_ud_rcv()
48 * while this is being called.
49 */
ipath_ud_loopback(struct ipath_qp * sqp,struct ipath_swqe * swqe)50 static void ipath_ud_loopback(struct ipath_qp *sqp, struct ipath_swqe *swqe)
51 {
52 struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
53 struct ipath_qp *qp;
54 struct ib_ah_attr *ah_attr;
55 unsigned long flags;
56 struct ipath_rq *rq;
57 struct ipath_srq *srq;
58 struct ipath_sge_state rsge;
59 struct ipath_sge *sge;
60 struct ipath_rwq *wq;
61 struct ipath_rwqe *wqe;
62 void (*handler)(struct ib_event *, void *);
63 struct ib_wc wc;
64 u32 tail;
65 u32 rlen;
66 u32 length;
67
68 qp = ipath_lookup_qpn(&dev->qp_table, swqe->wr.wr.ud.remote_qpn);
69 if (!qp || !(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_RECV_OK)) {
70 dev->n_pkt_drops++;
71 goto done;
72 }
73
74 /*
75 * Check that the qkey matches (except for QP0, see 9.6.1.4.1).
76 * Qkeys with the high order bit set mean use the
77 * qkey from the QP context instead of the WR (see 10.2.5).
78 */
79 if (unlikely(qp->ibqp.qp_num &&
80 ((int) swqe->wr.wr.ud.remote_qkey < 0 ?
81 sqp->qkey : swqe->wr.wr.ud.remote_qkey) != qp->qkey)) {
82 /* XXX OK to lose a count once in a while. */
83 dev->qkey_violations++;
84 dev->n_pkt_drops++;
85 goto drop;
86 }
87
88 /*
89 * A GRH is expected to precede the data even if not
90 * present on the wire.
91 */
92 length = swqe->length;
93 memset(&wc, 0, sizeof wc);
94 wc.byte_len = length + sizeof(struct ib_grh);
95
96 if (swqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
97 wc.wc_flags = IB_WC_WITH_IMM;
98 wc.ex.imm_data = swqe->wr.ex.imm_data;
99 }
100
101 /*
102 * This would be a lot simpler if we could call ipath_get_rwqe()
103 * but that uses state that the receive interrupt handler uses
104 * so we would need to lock out receive interrupts while doing
105 * local loopback.
106 */
107 if (qp->ibqp.srq) {
108 srq = to_isrq(qp->ibqp.srq);
109 handler = srq->ibsrq.event_handler;
110 rq = &srq->rq;
111 } else {
112 srq = NULL;
113 handler = NULL;
114 rq = &qp->r_rq;
115 }
116
117 /*
118 * Get the next work request entry to find where to put the data.
119 * Note that it is safe to drop the lock after changing rq->tail
120 * since ipath_post_receive() won't fill the empty slot.
121 */
122 spin_lock_irqsave(&rq->lock, flags);
123 wq = rq->wq;
124 tail = wq->tail;
125 /* Validate tail before using it since it is user writable. */
126 if (tail >= rq->size)
127 tail = 0;
128 if (unlikely(tail == wq->head)) {
129 spin_unlock_irqrestore(&rq->lock, flags);
130 dev->n_pkt_drops++;
131 goto drop;
132 }
133 wqe = get_rwqe_ptr(rq, tail);
134 rsge.sg_list = qp->r_ud_sg_list;
135 if (!ipath_init_sge(qp, wqe, &rlen, &rsge)) {
136 spin_unlock_irqrestore(&rq->lock, flags);
137 dev->n_pkt_drops++;
138 goto drop;
139 }
140 /* Silently drop packets which are too big. */
141 if (wc.byte_len > rlen) {
142 spin_unlock_irqrestore(&rq->lock, flags);
143 dev->n_pkt_drops++;
144 goto drop;
145 }
146 if (++tail >= rq->size)
147 tail = 0;
148 wq->tail = tail;
149 wc.wr_id = wqe->wr_id;
150 if (handler) {
151 u32 n;
152
153 /*
154 * validate head pointer value and compute
155 * the number of remaining WQEs.
156 */
157 n = wq->head;
158 if (n >= rq->size)
159 n = 0;
160 if (n < tail)
161 n += rq->size - tail;
162 else
163 n -= tail;
164 if (n < srq->limit) {
165 struct ib_event ev;
166
167 srq->limit = 0;
168 spin_unlock_irqrestore(&rq->lock, flags);
169 ev.device = qp->ibqp.device;
170 ev.element.srq = qp->ibqp.srq;
171 ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
172 handler(&ev, srq->ibsrq.srq_context);
173 } else
174 spin_unlock_irqrestore(&rq->lock, flags);
175 } else
176 spin_unlock_irqrestore(&rq->lock, flags);
177
178 ah_attr = &to_iah(swqe->wr.wr.ud.ah)->attr;
179 if (ah_attr->ah_flags & IB_AH_GRH) {
180 ipath_copy_sge(&rsge, &ah_attr->grh, sizeof(struct ib_grh));
181 wc.wc_flags |= IB_WC_GRH;
182 } else
183 ipath_skip_sge(&rsge, sizeof(struct ib_grh));
184 sge = swqe->sg_list;
185 while (length) {
186 u32 len = sge->length;
187
188 if (len > length)
189 len = length;
190 if (len > sge->sge_length)
191 len = sge->sge_length;
192 BUG_ON(len == 0);
193 ipath_copy_sge(&rsge, sge->vaddr, len);
194 sge->vaddr += len;
195 sge->length -= len;
196 sge->sge_length -= len;
197 if (sge->sge_length == 0) {
198 if (--swqe->wr.num_sge)
199 sge++;
200 } else if (sge->length == 0 && sge->mr != NULL) {
201 if (++sge->n >= IPATH_SEGSZ) {
202 if (++sge->m >= sge->mr->mapsz)
203 break;
204 sge->n = 0;
205 }
206 sge->vaddr =
207 sge->mr->map[sge->m]->segs[sge->n].vaddr;
208 sge->length =
209 sge->mr->map[sge->m]->segs[sge->n].length;
210 }
211 length -= len;
212 }
213 wc.status = IB_WC_SUCCESS;
214 wc.opcode = IB_WC_RECV;
215 wc.qp = &qp->ibqp;
216 wc.src_qp = sqp->ibqp.qp_num;
217 /* XXX do we know which pkey matched? Only needed for GSI. */
218 wc.pkey_index = 0;
219 wc.slid = dev->dd->ipath_lid |
220 (ah_attr->src_path_bits &
221 ((1 << dev->dd->ipath_lmc) - 1));
222 wc.sl = ah_attr->sl;
223 wc.dlid_path_bits =
224 ah_attr->dlid & ((1 << dev->dd->ipath_lmc) - 1);
225 wc.port_num = 1;
226 /* Signal completion event if the solicited bit is set. */
227 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
228 swqe->wr.send_flags & IB_SEND_SOLICITED);
229 drop:
230 if (atomic_dec_and_test(&qp->refcount))
231 wake_up(&qp->wait);
232 done:;
233 }
234
235 /**
236 * ipath_make_ud_req - construct a UD request packet
237 * @qp: the QP
238 *
239 * Return 1 if constructed; otherwise, return 0.
240 */
ipath_make_ud_req(struct ipath_qp * qp)241 int ipath_make_ud_req(struct ipath_qp *qp)
242 {
243 struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
244 struct ipath_other_headers *ohdr;
245 struct ib_ah_attr *ah_attr;
246 struct ipath_swqe *wqe;
247 unsigned long flags;
248 u32 nwords;
249 u32 extra_bytes;
250 u32 bth0;
251 u16 lrh0;
252 u16 lid;
253 int ret = 0;
254 int next_cur;
255
256 spin_lock_irqsave(&qp->s_lock, flags);
257
258 if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_NEXT_SEND_OK)) {
259 if (!(ib_ipath_state_ops[qp->state] & IPATH_FLUSH_SEND))
260 goto bail;
261 /* We are in the error state, flush the work request. */
262 if (qp->s_last == qp->s_head)
263 goto bail;
264 /* If DMAs are in progress, we can't flush immediately. */
265 if (atomic_read(&qp->s_dma_busy)) {
266 qp->s_flags |= IPATH_S_WAIT_DMA;
267 goto bail;
268 }
269 wqe = get_swqe_ptr(qp, qp->s_last);
270 ipath_send_complete(qp, wqe, IB_WC_WR_FLUSH_ERR);
271 goto done;
272 }
273
274 if (qp->s_cur == qp->s_head)
275 goto bail;
276
277 wqe = get_swqe_ptr(qp, qp->s_cur);
278 next_cur = qp->s_cur + 1;
279 if (next_cur >= qp->s_size)
280 next_cur = 0;
281
282 /* Construct the header. */
283 ah_attr = &to_iah(wqe->wr.wr.ud.ah)->attr;
284 if (ah_attr->dlid >= IPATH_MULTICAST_LID_BASE) {
285 if (ah_attr->dlid != IPATH_PERMISSIVE_LID)
286 dev->n_multicast_xmit++;
287 else
288 dev->n_unicast_xmit++;
289 } else {
290 dev->n_unicast_xmit++;
291 lid = ah_attr->dlid & ~((1 << dev->dd->ipath_lmc) - 1);
292 if (unlikely(lid == dev->dd->ipath_lid)) {
293 /*
294 * If DMAs are in progress, we can't generate
295 * a completion for the loopback packet since
296 * it would be out of order.
297 * XXX Instead of waiting, we could queue a
298 * zero length descriptor so we get a callback.
299 */
300 if (atomic_read(&qp->s_dma_busy)) {
301 qp->s_flags |= IPATH_S_WAIT_DMA;
302 goto bail;
303 }
304 qp->s_cur = next_cur;
305 spin_unlock_irqrestore(&qp->s_lock, flags);
306 ipath_ud_loopback(qp, wqe);
307 spin_lock_irqsave(&qp->s_lock, flags);
308 ipath_send_complete(qp, wqe, IB_WC_SUCCESS);
309 goto done;
310 }
311 }
312
313 qp->s_cur = next_cur;
314 extra_bytes = -wqe->length & 3;
315 nwords = (wqe->length + extra_bytes) >> 2;
316
317 /* header size in 32-bit words LRH+BTH+DETH = (8+12+8)/4. */
318 qp->s_hdrwords = 7;
319 qp->s_cur_size = wqe->length;
320 qp->s_cur_sge = &qp->s_sge;
321 qp->s_dmult = ah_attr->static_rate;
322 qp->s_wqe = wqe;
323 qp->s_sge.sge = wqe->sg_list[0];
324 qp->s_sge.sg_list = wqe->sg_list + 1;
325 qp->s_sge.num_sge = wqe->wr.num_sge;
326
327 if (ah_attr->ah_flags & IB_AH_GRH) {
328 /* Header size in 32-bit words. */
329 qp->s_hdrwords += ipath_make_grh(dev, &qp->s_hdr.u.l.grh,
330 &ah_attr->grh,
331 qp->s_hdrwords, nwords);
332 lrh0 = IPATH_LRH_GRH;
333 ohdr = &qp->s_hdr.u.l.oth;
334 /*
335 * Don't worry about sending to locally attached multicast
336 * QPs. It is unspecified by the spec. what happens.
337 */
338 } else {
339 /* Header size in 32-bit words. */
340 lrh0 = IPATH_LRH_BTH;
341 ohdr = &qp->s_hdr.u.oth;
342 }
343 if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
344 qp->s_hdrwords++;
345 ohdr->u.ud.imm_data = wqe->wr.ex.imm_data;
346 bth0 = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE << 24;
347 } else
348 bth0 = IB_OPCODE_UD_SEND_ONLY << 24;
349 lrh0 |= ah_attr->sl << 4;
350 if (qp->ibqp.qp_type == IB_QPT_SMI)
351 lrh0 |= 0xF000; /* Set VL (see ch. 13.5.3.1) */
352 qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
353 qp->s_hdr.lrh[1] = cpu_to_be16(ah_attr->dlid); /* DEST LID */
354 qp->s_hdr.lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords +
355 SIZE_OF_CRC);
356 lid = dev->dd->ipath_lid;
357 if (lid) {
358 lid |= ah_attr->src_path_bits &
359 ((1 << dev->dd->ipath_lmc) - 1);
360 qp->s_hdr.lrh[3] = cpu_to_be16(lid);
361 } else
362 qp->s_hdr.lrh[3] = IB_LID_PERMISSIVE;
363 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
364 bth0 |= 1 << 23;
365 bth0 |= extra_bytes << 20;
366 bth0 |= qp->ibqp.qp_type == IB_QPT_SMI ? IPATH_DEFAULT_P_KEY :
367 ipath_get_pkey(dev->dd, qp->s_pkey_index);
368 ohdr->bth[0] = cpu_to_be32(bth0);
369 /*
370 * Use the multicast QP if the destination LID is a multicast LID.
371 */
372 ohdr->bth[1] = ah_attr->dlid >= IPATH_MULTICAST_LID_BASE &&
373 ah_attr->dlid != IPATH_PERMISSIVE_LID ?
374 cpu_to_be32(IPATH_MULTICAST_QPN) :
375 cpu_to_be32(wqe->wr.wr.ud.remote_qpn);
376 ohdr->bth[2] = cpu_to_be32(qp->s_next_psn++ & IPATH_PSN_MASK);
377 /*
378 * Qkeys with the high order bit set mean use the
379 * qkey from the QP context instead of the WR (see 10.2.5).
380 */
381 ohdr->u.ud.deth[0] = cpu_to_be32((int)wqe->wr.wr.ud.remote_qkey < 0 ?
382 qp->qkey : wqe->wr.wr.ud.remote_qkey);
383 ohdr->u.ud.deth[1] = cpu_to_be32(qp->ibqp.qp_num);
384
385 done:
386 ret = 1;
387 goto unlock;
388
389 bail:
390 qp->s_flags &= ~IPATH_S_BUSY;
391 unlock:
392 spin_unlock_irqrestore(&qp->s_lock, flags);
393 return ret;
394 }
395
396 /**
397 * ipath_ud_rcv - receive an incoming UD packet
398 * @dev: the device the packet came in on
399 * @hdr: the packet header
400 * @has_grh: true if the packet has a GRH
401 * @data: the packet data
402 * @tlen: the packet length
403 * @qp: the QP the packet came on
404 *
405 * This is called from ipath_qp_rcv() to process an incoming UD packet
406 * for the given QP.
407 * Called at interrupt level.
408 */
ipath_ud_rcv(struct ipath_ibdev * dev,struct ipath_ib_header * hdr,int has_grh,void * data,u32 tlen,struct ipath_qp * qp)409 void ipath_ud_rcv(struct ipath_ibdev *dev, struct ipath_ib_header *hdr,
410 int has_grh, void *data, u32 tlen, struct ipath_qp *qp)
411 {
412 struct ipath_other_headers *ohdr;
413 int opcode;
414 u32 hdrsize;
415 u32 pad;
416 struct ib_wc wc;
417 u32 qkey;
418 u32 src_qp;
419 u16 dlid;
420 int header_in_data;
421
422 /* Check for GRH */
423 if (!has_grh) {
424 ohdr = &hdr->u.oth;
425 hdrsize = 8 + 12 + 8; /* LRH + BTH + DETH */
426 qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
427 src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
428 header_in_data = 0;
429 } else {
430 ohdr = &hdr->u.l.oth;
431 hdrsize = 8 + 40 + 12 + 8; /* LRH + GRH + BTH + DETH */
432 /*
433 * The header with GRH is 68 bytes and the core driver sets
434 * the eager header buffer size to 56 bytes so the last 12
435 * bytes of the IB header is in the data buffer.
436 */
437 header_in_data = dev->dd->ipath_rcvhdrentsize == 16;
438 if (header_in_data) {
439 qkey = be32_to_cpu(((__be32 *) data)[1]);
440 src_qp = be32_to_cpu(((__be32 *) data)[2]);
441 data += 12;
442 } else {
443 qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
444 src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
445 }
446 }
447 src_qp &= IPATH_QPN_MASK;
448
449 /*
450 * Check that the permissive LID is only used on QP0
451 * and the QKEY matches (see 9.6.1.4.1 and 9.6.1.5.1).
452 */
453 if (qp->ibqp.qp_num) {
454 if (unlikely(hdr->lrh[1] == IB_LID_PERMISSIVE ||
455 hdr->lrh[3] == IB_LID_PERMISSIVE)) {
456 dev->n_pkt_drops++;
457 goto bail;
458 }
459 if (unlikely(qkey != qp->qkey)) {
460 /* XXX OK to lose a count once in a while. */
461 dev->qkey_violations++;
462 dev->n_pkt_drops++;
463 goto bail;
464 }
465 } else if (hdr->lrh[1] == IB_LID_PERMISSIVE ||
466 hdr->lrh[3] == IB_LID_PERMISSIVE) {
467 struct ib_smp *smp = (struct ib_smp *) data;
468
469 if (smp->mgmt_class != IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) {
470 dev->n_pkt_drops++;
471 goto bail;
472 }
473 }
474
475 /*
476 * The opcode is in the low byte when its in network order
477 * (top byte when in host order).
478 */
479 opcode = be32_to_cpu(ohdr->bth[0]) >> 24;
480 if (qp->ibqp.qp_num > 1 &&
481 opcode == IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE) {
482 if (header_in_data) {
483 wc.ex.imm_data = *(__be32 *) data;
484 data += sizeof(__be32);
485 } else
486 wc.ex.imm_data = ohdr->u.ud.imm_data;
487 wc.wc_flags = IB_WC_WITH_IMM;
488 hdrsize += sizeof(u32);
489 } else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
490 wc.ex.imm_data = 0;
491 wc.wc_flags = 0;
492 } else {
493 dev->n_pkt_drops++;
494 goto bail;
495 }
496
497 /* Get the number of bytes the message was padded by. */
498 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
499 if (unlikely(tlen < (hdrsize + pad + 4))) {
500 /* Drop incomplete packets. */
501 dev->n_pkt_drops++;
502 goto bail;
503 }
504 tlen -= hdrsize + pad + 4;
505
506 /* Drop invalid MAD packets (see 13.5.3.1). */
507 if (unlikely((qp->ibqp.qp_num == 0 &&
508 (tlen != 256 ||
509 (be16_to_cpu(hdr->lrh[0]) >> 12) != 15)) ||
510 (qp->ibqp.qp_num == 1 &&
511 (tlen != 256 ||
512 (be16_to_cpu(hdr->lrh[0]) >> 12) == 15)))) {
513 dev->n_pkt_drops++;
514 goto bail;
515 }
516
517 /*
518 * A GRH is expected to precede the data even if not
519 * present on the wire.
520 */
521 wc.byte_len = tlen + sizeof(struct ib_grh);
522
523 /*
524 * Get the next work request entry to find where to put the data.
525 */
526 if (qp->r_flags & IPATH_R_REUSE_SGE)
527 qp->r_flags &= ~IPATH_R_REUSE_SGE;
528 else if (!ipath_get_rwqe(qp, 0)) {
529 /*
530 * Count VL15 packets dropped due to no receive buffer.
531 * Otherwise, count them as buffer overruns since usually,
532 * the HW will be able to receive packets even if there are
533 * no QPs with posted receive buffers.
534 */
535 if (qp->ibqp.qp_num == 0)
536 dev->n_vl15_dropped++;
537 else
538 dev->rcv_errors++;
539 goto bail;
540 }
541 /* Silently drop packets which are too big. */
542 if (wc.byte_len > qp->r_len) {
543 qp->r_flags |= IPATH_R_REUSE_SGE;
544 dev->n_pkt_drops++;
545 goto bail;
546 }
547 if (has_grh) {
548 ipath_copy_sge(&qp->r_sge, &hdr->u.l.grh,
549 sizeof(struct ib_grh));
550 wc.wc_flags |= IB_WC_GRH;
551 } else
552 ipath_skip_sge(&qp->r_sge, sizeof(struct ib_grh));
553 ipath_copy_sge(&qp->r_sge, data,
554 wc.byte_len - sizeof(struct ib_grh));
555 if (!test_and_clear_bit(IPATH_R_WRID_VALID, &qp->r_aflags))
556 goto bail;
557 wc.wr_id = qp->r_wr_id;
558 wc.status = IB_WC_SUCCESS;
559 wc.opcode = IB_WC_RECV;
560 wc.vendor_err = 0;
561 wc.qp = &qp->ibqp;
562 wc.src_qp = src_qp;
563 /* XXX do we know which pkey matched? Only needed for GSI. */
564 wc.pkey_index = 0;
565 wc.slid = be16_to_cpu(hdr->lrh[3]);
566 wc.sl = (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF;
567 dlid = be16_to_cpu(hdr->lrh[1]);
568 /*
569 * Save the LMC lower bits if the destination LID is a unicast LID.
570 */
571 wc.dlid_path_bits = dlid >= IPATH_MULTICAST_LID_BASE ? 0 :
572 dlid & ((1 << dev->dd->ipath_lmc) - 1);
573 wc.port_num = 1;
574 /* Signal completion event if the solicited bit is set. */
575 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
576 (ohdr->bth[0] &
577 cpu_to_be32(1 << 23)) != 0);
578
579 bail:;
580 }
581