Merge branch 'sglist-arch' into for-linus
[linux-2.6] / drivers / infiniband / hw / ipath / ipath_ud.c
1 /*
2  * Copyright (c) 2006, 2007 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 <rdma/ib_smi.h>
35
36 #include "ipath_verbs.h"
37 #include "ipath_kernel.h"
38
39 /**
40  * ipath_ud_loopback - handle send on loopback QPs
41  * @sqp: the sending QP
42  * @swqe: the send work request
43  *
44  * This is called from ipath_make_ud_req() to forward a WQE addressed
45  * to the same HCA.
46  * Note that the receive interrupt handler may be calling ipath_ud_rcv()
47  * while this is being called.
48  */
49 static void ipath_ud_loopback(struct ipath_qp *sqp, struct ipath_swqe *swqe)
50 {
51         struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
52         struct ipath_qp *qp;
53         struct ib_ah_attr *ah_attr;
54         unsigned long flags;
55         struct ipath_rq *rq;
56         struct ipath_srq *srq;
57         struct ipath_sge_state rsge;
58         struct ipath_sge *sge;
59         struct ipath_rwq *wq;
60         struct ipath_rwqe *wqe;
61         void (*handler)(struct ib_event *, void *);
62         struct ib_wc wc;
63         u32 tail;
64         u32 rlen;
65         u32 length;
66
67         qp = ipath_lookup_qpn(&dev->qp_table, swqe->wr.wr.ud.remote_qpn);
68         if (!qp) {
69                 dev->n_pkt_drops++;
70                 goto send_comp;
71         }
72
73         rsge.sg_list = NULL;
74
75         /*
76          * Check that the qkey matches (except for QP0, see 9.6.1.4.1).
77          * Qkeys with the high order bit set mean use the
78          * qkey from the QP context instead of the WR (see 10.2.5).
79          */
80         if (unlikely(qp->ibqp.qp_num &&
81                      ((int) swqe->wr.wr.ud.remote_qkey < 0 ?
82                       sqp->qkey : swqe->wr.wr.ud.remote_qkey) != qp->qkey)) {
83                 /* XXX OK to lose a count once in a while. */
84                 dev->qkey_violations++;
85                 dev->n_pkt_drops++;
86                 goto drop;
87         }
88
89         /*
90          * A GRH is expected to preceed the data even if not
91          * present on the wire.
92          */
93         length = swqe->length;
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.imm_data = swqe->wr.imm_data;
99         } else {
100                 wc.wc_flags = 0;
101                 wc.imm_data = 0;
102         }
103
104         /*
105          * This would be a lot simpler if we could call ipath_get_rwqe()
106          * but that uses state that the receive interrupt handler uses
107          * so we would need to lock out receive interrupts while doing
108          * local loopback.
109          */
110         if (qp->ibqp.srq) {
111                 srq = to_isrq(qp->ibqp.srq);
112                 handler = srq->ibsrq.event_handler;
113                 rq = &srq->rq;
114         } else {
115                 srq = NULL;
116                 handler = NULL;
117                 rq = &qp->r_rq;
118         }
119
120         if (rq->max_sge > 1) {
121                 /*
122                  * XXX We could use GFP_KERNEL if ipath_do_send()
123                  * was always called from the tasklet instead of
124                  * from ipath_post_send().
125                  */
126                 rsge.sg_list = kmalloc((rq->max_sge - 1) *
127                                         sizeof(struct ipath_sge),
128                                        GFP_ATOMIC);
129                 if (!rsge.sg_list) {
130                         dev->n_pkt_drops++;
131                         goto drop;
132                 }
133         }
134
135         /*
136          * Get the next work request entry to find where to put the data.
137          * Note that it is safe to drop the lock after changing rq->tail
138          * since ipath_post_receive() won't fill the empty slot.
139          */
140         spin_lock_irqsave(&rq->lock, flags);
141         wq = rq->wq;
142         tail = wq->tail;
143         /* Validate tail before using it since it is user writable. */
144         if (tail >= rq->size)
145                 tail = 0;
146         if (unlikely(tail == wq->head)) {
147                 spin_unlock_irqrestore(&rq->lock, flags);
148                 dev->n_pkt_drops++;
149                 goto drop;
150         }
151         wqe = get_rwqe_ptr(rq, tail);
152         if (!ipath_init_sge(qp, wqe, &rlen, &rsge)) {
153                 spin_unlock_irqrestore(&rq->lock, flags);
154                 dev->n_pkt_drops++;
155                 goto drop;
156         }
157         /* Silently drop packets which are too big. */
158         if (wc.byte_len > rlen) {
159                 spin_unlock_irqrestore(&rq->lock, flags);
160                 dev->n_pkt_drops++;
161                 goto drop;
162         }
163         if (++tail >= rq->size)
164                 tail = 0;
165         wq->tail = tail;
166         wc.wr_id = wqe->wr_id;
167         if (handler) {
168                 u32 n;
169
170                 /*
171                  * validate head pointer value and compute
172                  * the number of remaining WQEs.
173                  */
174                 n = wq->head;
175                 if (n >= rq->size)
176                         n = 0;
177                 if (n < tail)
178                         n += rq->size - tail;
179                 else
180                         n -= tail;
181                 if (n < srq->limit) {
182                         struct ib_event ev;
183
184                         srq->limit = 0;
185                         spin_unlock_irqrestore(&rq->lock, flags);
186                         ev.device = qp->ibqp.device;
187                         ev.element.srq = qp->ibqp.srq;
188                         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
189                         handler(&ev, srq->ibsrq.srq_context);
190                 } else
191                         spin_unlock_irqrestore(&rq->lock, flags);
192         } else
193                 spin_unlock_irqrestore(&rq->lock, flags);
194
195         ah_attr = &to_iah(swqe->wr.wr.ud.ah)->attr;
196         if (ah_attr->ah_flags & IB_AH_GRH) {
197                 ipath_copy_sge(&rsge, &ah_attr->grh, sizeof(struct ib_grh));
198                 wc.wc_flags |= IB_WC_GRH;
199         } else
200                 ipath_skip_sge(&rsge, sizeof(struct ib_grh));
201         sge = swqe->sg_list;
202         while (length) {
203                 u32 len = sge->length;
204
205                 if (len > length)
206                         len = length;
207                 if (len > sge->sge_length)
208                         len = sge->sge_length;
209                 BUG_ON(len == 0);
210                 ipath_copy_sge(&rsge, sge->vaddr, len);
211                 sge->vaddr += len;
212                 sge->length -= len;
213                 sge->sge_length -= len;
214                 if (sge->sge_length == 0) {
215                         if (--swqe->wr.num_sge)
216                                 sge++;
217                 } else if (sge->length == 0 && sge->mr != NULL) {
218                         if (++sge->n >= IPATH_SEGSZ) {
219                                 if (++sge->m >= sge->mr->mapsz)
220                                         break;
221                                 sge->n = 0;
222                         }
223                         sge->vaddr =
224                                 sge->mr->map[sge->m]->segs[sge->n].vaddr;
225                         sge->length =
226                                 sge->mr->map[sge->m]->segs[sge->n].length;
227                 }
228                 length -= len;
229         }
230         wc.status = IB_WC_SUCCESS;
231         wc.opcode = IB_WC_RECV;
232         wc.vendor_err = 0;
233         wc.qp = &qp->ibqp;
234         wc.src_qp = sqp->ibqp.qp_num;
235         /* XXX do we know which pkey matched? Only needed for GSI. */
236         wc.pkey_index = 0;
237         wc.slid = dev->dd->ipath_lid |
238                 (ah_attr->src_path_bits &
239                  ((1 << dev->dd->ipath_lmc) - 1));
240         wc.sl = ah_attr->sl;
241         wc.dlid_path_bits =
242                 ah_attr->dlid & ((1 << dev->dd->ipath_lmc) - 1);
243         wc.port_num = 1;
244         /* Signal completion event if the solicited bit is set. */
245         ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
246                        swqe->wr.send_flags & IB_SEND_SOLICITED);
247 drop:
248         kfree(rsge.sg_list);
249         if (atomic_dec_and_test(&qp->refcount))
250                 wake_up(&qp->wait);
251 send_comp:
252         ipath_send_complete(sqp, swqe, IB_WC_SUCCESS);
253 }
254
255 /**
256  * ipath_make_ud_req - construct a UD request packet
257  * @qp: the QP
258  *
259  * Return 1 if constructed; otherwise, return 0.
260  */
261 int ipath_make_ud_req(struct ipath_qp *qp)
262 {
263         struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
264         struct ipath_other_headers *ohdr;
265         struct ib_ah_attr *ah_attr;
266         struct ipath_swqe *wqe;
267         u32 nwords;
268         u32 extra_bytes;
269         u32 bth0;
270         u16 lrh0;
271         u16 lid;
272         int ret = 0;
273
274         if (unlikely(!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK)))
275                 goto bail;
276
277         if (qp->s_cur == qp->s_head)
278                 goto bail;
279
280         wqe = get_swqe_ptr(qp, qp->s_cur);
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 &
292                         ~((1 << dev->dd->ipath_lmc) - 1);
293                 if (unlikely(lid == dev->dd->ipath_lid)) {
294                         ipath_ud_loopback(qp, wqe);
295                         goto done;
296                 }
297         }
298
299         extra_bytes = -wqe->length & 3;
300         nwords = (wqe->length + extra_bytes) >> 2;
301
302         /* header size in 32-bit words LRH+BTH+DETH = (8+12+8)/4. */
303         qp->s_hdrwords = 7;
304         if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM)
305                 qp->s_hdrwords++;
306         qp->s_cur_size = wqe->length;
307         qp->s_cur_sge = &qp->s_sge;
308         qp->s_wqe = wqe;
309         qp->s_sge.sge = wqe->sg_list[0];
310         qp->s_sge.sg_list = wqe->sg_list + 1;
311         qp->s_sge.num_sge = wqe->wr.num_sge;
312
313         if (ah_attr->ah_flags & IB_AH_GRH) {
314                 /* Header size in 32-bit words. */
315                 qp->s_hdrwords += ipath_make_grh(dev, &qp->s_hdr.u.l.grh,
316                                                  &ah_attr->grh,
317                                                  qp->s_hdrwords, nwords);
318                 lrh0 = IPATH_LRH_GRH;
319                 ohdr = &qp->s_hdr.u.l.oth;
320                 /*
321                  * Don't worry about sending to locally attached multicast
322                  * QPs.  It is unspecified by the spec. what happens.
323                  */
324         } else {
325                 /* Header size in 32-bit words. */
326                 lrh0 = IPATH_LRH_BTH;
327                 ohdr = &qp->s_hdr.u.oth;
328         }
329         if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
330                 ohdr->u.ud.imm_data = wqe->wr.imm_data;
331                 bth0 = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE << 24;
332         } else
333                 bth0 = IB_OPCODE_UD_SEND_ONLY << 24;
334         lrh0 |= ah_attr->sl << 4;
335         if (qp->ibqp.qp_type == IB_QPT_SMI)
336                 lrh0 |= 0xF000; /* Set VL (see ch. 13.5.3.1) */
337         qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
338         qp->s_hdr.lrh[1] = cpu_to_be16(ah_attr->dlid);  /* DEST LID */
339         qp->s_hdr.lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords +
340                                            SIZE_OF_CRC);
341         lid = dev->dd->ipath_lid;
342         if (lid) {
343                 lid |= ah_attr->src_path_bits &
344                         ((1 << dev->dd->ipath_lmc) - 1);
345                 qp->s_hdr.lrh[3] = cpu_to_be16(lid);
346         } else
347                 qp->s_hdr.lrh[3] = IB_LID_PERMISSIVE;
348         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
349                 bth0 |= 1 << 23;
350         bth0 |= extra_bytes << 20;
351         bth0 |= qp->ibqp.qp_type == IB_QPT_SMI ? IPATH_DEFAULT_P_KEY :
352                 ipath_get_pkey(dev->dd, qp->s_pkey_index);
353         ohdr->bth[0] = cpu_to_be32(bth0);
354         /*
355          * Use the multicast QP if the destination LID is a multicast LID.
356          */
357         ohdr->bth[1] = ah_attr->dlid >= IPATH_MULTICAST_LID_BASE &&
358                 ah_attr->dlid != IPATH_PERMISSIVE_LID ?
359                 __constant_cpu_to_be32(IPATH_MULTICAST_QPN) :
360                 cpu_to_be32(wqe->wr.wr.ud.remote_qpn);
361         ohdr->bth[2] = cpu_to_be32(qp->s_next_psn++ & IPATH_PSN_MASK);
362         /*
363          * Qkeys with the high order bit set mean use the
364          * qkey from the QP context instead of the WR (see 10.2.5).
365          */
366         ohdr->u.ud.deth[0] = cpu_to_be32((int)wqe->wr.wr.ud.remote_qkey < 0 ?
367                                          qp->qkey : wqe->wr.wr.ud.remote_qkey);
368         ohdr->u.ud.deth[1] = cpu_to_be32(qp->ibqp.qp_num);
369
370 done:
371         if (++qp->s_cur >= qp->s_size)
372                 qp->s_cur = 0;
373         ret = 1;
374
375 bail:
376         return ret;
377 }
378
379 /**
380  * ipath_ud_rcv - receive an incoming UD packet
381  * @dev: the device the packet came in on
382  * @hdr: the packet header
383  * @has_grh: true if the packet has a GRH
384  * @data: the packet data
385  * @tlen: the packet length
386  * @qp: the QP the packet came on
387  *
388  * This is called from ipath_qp_rcv() to process an incoming UD packet
389  * for the given QP.
390  * Called at interrupt level.
391  */
392 void ipath_ud_rcv(struct ipath_ibdev *dev, struct ipath_ib_header *hdr,
393                   int has_grh, void *data, u32 tlen, struct ipath_qp *qp)
394 {
395         struct ipath_other_headers *ohdr;
396         int opcode;
397         u32 hdrsize;
398         u32 pad;
399         struct ib_wc wc;
400         u32 qkey;
401         u32 src_qp;
402         u16 dlid;
403         int header_in_data;
404
405         /* Check for GRH */
406         if (!has_grh) {
407                 ohdr = &hdr->u.oth;
408                 hdrsize = 8 + 12 + 8;   /* LRH + BTH + DETH */
409                 qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
410                 src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
411                 header_in_data = 0;
412         } else {
413                 ohdr = &hdr->u.l.oth;
414                 hdrsize = 8 + 40 + 12 + 8; /* LRH + GRH + BTH + DETH */
415                 /*
416                  * The header with GRH is 68 bytes and the core driver sets
417                  * the eager header buffer size to 56 bytes so the last 12
418                  * bytes of the IB header is in the data buffer.
419                  */
420                 header_in_data = dev->dd->ipath_rcvhdrentsize == 16;
421                 if (header_in_data) {
422                         qkey = be32_to_cpu(((__be32 *) data)[1]);
423                         src_qp = be32_to_cpu(((__be32 *) data)[2]);
424                         data += 12;
425                 } else {
426                         qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
427                         src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
428                 }
429         }
430         src_qp &= IPATH_QPN_MASK;
431
432         /*
433          * Check that the permissive LID is only used on QP0
434          * and the QKEY matches (see 9.6.1.4.1 and 9.6.1.5.1).
435          */
436         if (qp->ibqp.qp_num) {
437                 if (unlikely(hdr->lrh[1] == IB_LID_PERMISSIVE ||
438                              hdr->lrh[3] == IB_LID_PERMISSIVE)) {
439                         dev->n_pkt_drops++;
440                         goto bail;
441                 }
442                 if (unlikely(qkey != qp->qkey)) {
443                         /* XXX OK to lose a count once in a while. */
444                         dev->qkey_violations++;
445                         dev->n_pkt_drops++;
446                         goto bail;
447                 }
448         } else if (hdr->lrh[1] == IB_LID_PERMISSIVE ||
449                    hdr->lrh[3] == IB_LID_PERMISSIVE) {
450                 struct ib_smp *smp = (struct ib_smp *) data;
451
452                 if (smp->mgmt_class != IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) {
453                         dev->n_pkt_drops++;
454                         goto bail;
455                 }
456         }
457
458         /* Get the number of bytes the message was padded by. */
459         pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
460         if (unlikely(tlen < (hdrsize + pad + 4))) {
461                 /* Drop incomplete packets. */
462                 dev->n_pkt_drops++;
463                 goto bail;
464         }
465         tlen -= hdrsize + pad + 4;
466
467         /* Drop invalid MAD packets (see 13.5.3.1). */
468         if (unlikely((qp->ibqp.qp_num == 0 &&
469                       (tlen != 256 ||
470                        (be16_to_cpu(hdr->lrh[0]) >> 12) != 15)) ||
471                      (qp->ibqp.qp_num == 1 &&
472                       (tlen != 256 ||
473                        (be16_to_cpu(hdr->lrh[0]) >> 12) == 15)))) {
474                 dev->n_pkt_drops++;
475                 goto bail;
476         }
477
478         /*
479          * A GRH is expected to preceed the data even if not
480          * present on the wire.
481          */
482         wc.byte_len = tlen + sizeof(struct ib_grh);
483
484         /*
485          * The opcode is in the low byte when its in network order
486          * (top byte when in host order).
487          */
488         opcode = be32_to_cpu(ohdr->bth[0]) >> 24;
489         if (qp->ibqp.qp_num > 1 &&
490             opcode == IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE) {
491                 if (header_in_data) {
492                         wc.imm_data = *(__be32 *) data;
493                         data += sizeof(__be32);
494                 } else
495                         wc.imm_data = ohdr->u.ud.imm_data;
496                 wc.wc_flags = IB_WC_WITH_IMM;
497                 hdrsize += sizeof(u32);
498         } else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
499                 wc.imm_data = 0;
500                 wc.wc_flags = 0;
501         } else {
502                 dev->n_pkt_drops++;
503                 goto bail;
504         }
505
506         /*
507          * Get the next work request entry to find where to put the data.
508          */
509         if (qp->r_reuse_sge)
510                 qp->r_reuse_sge = 0;
511         else if (!ipath_get_rwqe(qp, 0)) {
512                 /*
513                  * Count VL15 packets dropped due to no receive buffer.
514                  * Otherwise, count them as buffer overruns since usually,
515                  * the HW will be able to receive packets even if there are
516                  * no QPs with posted receive buffers.
517                  */
518                 if (qp->ibqp.qp_num == 0)
519                         dev->n_vl15_dropped++;
520                 else
521                         dev->rcv_errors++;
522                 goto bail;
523         }
524         /* Silently drop packets which are too big. */
525         if (wc.byte_len > qp->r_len) {
526                 qp->r_reuse_sge = 1;
527                 dev->n_pkt_drops++;
528                 goto bail;
529         }
530         if (has_grh) {
531                 ipath_copy_sge(&qp->r_sge, &hdr->u.l.grh,
532                                sizeof(struct ib_grh));
533                 wc.wc_flags |= IB_WC_GRH;
534         } else
535                 ipath_skip_sge(&qp->r_sge, sizeof(struct ib_grh));
536         ipath_copy_sge(&qp->r_sge, data,
537                        wc.byte_len - sizeof(struct ib_grh));
538         qp->r_wrid_valid = 0;
539         wc.wr_id = qp->r_wr_id;
540         wc.status = IB_WC_SUCCESS;
541         wc.opcode = IB_WC_RECV;
542         wc.vendor_err = 0;
543         wc.qp = &qp->ibqp;
544         wc.src_qp = src_qp;
545         /* XXX do we know which pkey matched? Only needed for GSI. */
546         wc.pkey_index = 0;
547         wc.slid = be16_to_cpu(hdr->lrh[3]);
548         wc.sl = (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF;
549         dlid = be16_to_cpu(hdr->lrh[1]);
550         /*
551          * Save the LMC lower bits if the destination LID is a unicast LID.
552          */
553         wc.dlid_path_bits = dlid >= IPATH_MULTICAST_LID_BASE ? 0 :
554                 dlid & ((1 << dev->dd->ipath_lmc) - 1);
555         wc.port_num = 1;
556         /* Signal completion event if the solicited bit is set. */
557         ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
558                        (ohdr->bth[0] &
559                         __constant_cpu_to_be32(1 << 23)) != 0);
560
561 bail:;
562 }