IB/ipath: Remove useless comments
[linux-3.10.git] / drivers / infiniband / hw / ipath / ipath_qp.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 <linux/err.h>
35 #include <linux/vmalloc.h>
36
37 #include "ipath_verbs.h"
38 #include "ipath_kernel.h"
39
40 #define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
41 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
42 #define mk_qpn(qpt, map, off)   (((map) - (qpt)->map) * BITS_PER_PAGE + \
43                                  (off))
44 #define find_next_offset(map, off) find_next_zero_bit((map)->page, \
45                                                       BITS_PER_PAGE, off)
46
47 /*
48  * Convert the AETH credit code into the number of credits.
49  */
50 static u32 credit_table[31] = {
51         0,                      /* 0 */
52         1,                      /* 1 */
53         2,                      /* 2 */
54         3,                      /* 3 */
55         4,                      /* 4 */
56         6,                      /* 5 */
57         8,                      /* 6 */
58         12,                     /* 7 */
59         16,                     /* 8 */
60         24,                     /* 9 */
61         32,                     /* A */
62         48,                     /* B */
63         64,                     /* C */
64         96,                     /* D */
65         128,                    /* E */
66         192,                    /* F */
67         256,                    /* 10 */
68         384,                    /* 11 */
69         512,                    /* 12 */
70         768,                    /* 13 */
71         1024,                   /* 14 */
72         1536,                   /* 15 */
73         2048,                   /* 16 */
74         3072,                   /* 17 */
75         4096,                   /* 18 */
76         6144,                   /* 19 */
77         8192,                   /* 1A */
78         12288,                  /* 1B */
79         16384,                  /* 1C */
80         24576,                  /* 1D */
81         32768                   /* 1E */
82 };
83
84
85 static void get_map_page(struct ipath_qp_table *qpt, struct qpn_map *map)
86 {
87         unsigned long page = get_zeroed_page(GFP_KERNEL);
88         unsigned long flags;
89
90         /*
91          * Free the page if someone raced with us installing it.
92          */
93
94         spin_lock_irqsave(&qpt->lock, flags);
95         if (map->page)
96                 free_page(page);
97         else
98                 map->page = (void *)page;
99         spin_unlock_irqrestore(&qpt->lock, flags);
100 }
101
102
103 static int alloc_qpn(struct ipath_qp_table *qpt, enum ib_qp_type type)
104 {
105         u32 i, offset, max_scan, qpn;
106         struct qpn_map *map;
107         u32 ret = -1;
108
109         if (type == IB_QPT_SMI)
110                 ret = 0;
111         else if (type == IB_QPT_GSI)
112                 ret = 1;
113
114         if (ret != -1) {
115                 map = &qpt->map[0];
116                 if (unlikely(!map->page)) {
117                         get_map_page(qpt, map);
118                         if (unlikely(!map->page)) {
119                                 ret = -ENOMEM;
120                                 goto bail;
121                         }
122                 }
123                 if (!test_and_set_bit(ret, map->page))
124                         atomic_dec(&map->n_free);
125                 else
126                         ret = -EBUSY;
127                 goto bail;
128         }
129
130         qpn = qpt->last + 1;
131         if (qpn >= QPN_MAX)
132                 qpn = 2;
133         offset = qpn & BITS_PER_PAGE_MASK;
134         map = &qpt->map[qpn / BITS_PER_PAGE];
135         max_scan = qpt->nmaps - !offset;
136         for (i = 0;;) {
137                 if (unlikely(!map->page)) {
138                         get_map_page(qpt, map);
139                         if (unlikely(!map->page))
140                                 break;
141                 }
142                 if (likely(atomic_read(&map->n_free))) {
143                         do {
144                                 if (!test_and_set_bit(offset, map->page)) {
145                                         atomic_dec(&map->n_free);
146                                         qpt->last = qpn;
147                                         ret = qpn;
148                                         goto bail;
149                                 }
150                                 offset = find_next_offset(map, offset);
151                                 qpn = mk_qpn(qpt, map, offset);
152                                 /*
153                                  * This test differs from alloc_pidmap().
154                                  * If find_next_offset() does find a zero
155                                  * bit, we don't need to check for QPN
156                                  * wrapping around past our starting QPN.
157                                  * We just need to be sure we don't loop
158                                  * forever.
159                                  */
160                         } while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
161                 }
162                 /*
163                  * In order to keep the number of pages allocated to a
164                  * minimum, we scan the all existing pages before increasing
165                  * the size of the bitmap table.
166                  */
167                 if (++i > max_scan) {
168                         if (qpt->nmaps == QPNMAP_ENTRIES)
169                                 break;
170                         map = &qpt->map[qpt->nmaps++];
171                         offset = 0;
172                 } else if (map < &qpt->map[qpt->nmaps]) {
173                         ++map;
174                         offset = 0;
175                 } else {
176                         map = &qpt->map[0];
177                         offset = 2;
178                 }
179                 qpn = mk_qpn(qpt, map, offset);
180         }
181
182         ret = -ENOMEM;
183
184 bail:
185         return ret;
186 }
187
188 static void free_qpn(struct ipath_qp_table *qpt, u32 qpn)
189 {
190         struct qpn_map *map;
191
192         map = qpt->map + qpn / BITS_PER_PAGE;
193         if (map->page)
194                 clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
195         atomic_inc(&map->n_free);
196 }
197
198 /**
199  * ipath_alloc_qpn - allocate a QP number
200  * @qpt: the QP table
201  * @qp: the QP
202  * @type: the QP type (IB_QPT_SMI and IB_QPT_GSI are special)
203  *
204  * Allocate the next available QPN and put the QP into the hash table.
205  * The hash table holds a reference to the QP.
206  */
207 static int ipath_alloc_qpn(struct ipath_qp_table *qpt, struct ipath_qp *qp,
208                            enum ib_qp_type type)
209 {
210         unsigned long flags;
211         int ret;
212
213         ret = alloc_qpn(qpt, type);
214         if (ret < 0)
215                 goto bail;
216         qp->ibqp.qp_num = ret;
217
218         /* Add the QP to the hash table. */
219         spin_lock_irqsave(&qpt->lock, flags);
220
221         ret %= qpt->max;
222         qp->next = qpt->table[ret];
223         qpt->table[ret] = qp;
224         atomic_inc(&qp->refcount);
225
226         spin_unlock_irqrestore(&qpt->lock, flags);
227         ret = 0;
228
229 bail:
230         return ret;
231 }
232
233 /**
234  * ipath_free_qp - remove a QP from the QP table
235  * @qpt: the QP table
236  * @qp: the QP to remove
237  *
238  * Remove the QP from the table so it can't be found asynchronously by
239  * the receive interrupt routine.
240  */
241 static void ipath_free_qp(struct ipath_qp_table *qpt, struct ipath_qp *qp)
242 {
243         struct ipath_qp *q, **qpp;
244         unsigned long flags;
245         int fnd = 0;
246
247         spin_lock_irqsave(&qpt->lock, flags);
248
249         /* Remove QP from the hash table. */
250         qpp = &qpt->table[qp->ibqp.qp_num % qpt->max];
251         for (; (q = *qpp) != NULL; qpp = &q->next) {
252                 if (q == qp) {
253                         *qpp = qp->next;
254                         qp->next = NULL;
255                         atomic_dec(&qp->refcount);
256                         fnd = 1;
257                         break;
258                 }
259         }
260
261         spin_unlock_irqrestore(&qpt->lock, flags);
262
263         if (!fnd)
264                 return;
265
266         free_qpn(qpt, qp->ibqp.qp_num);
267
268         wait_event(qp->wait, !atomic_read(&qp->refcount));
269 }
270
271 /**
272  * ipath_free_all_qps - remove all QPs from the table
273  * @qpt: the QP table to empty
274  */
275 void ipath_free_all_qps(struct ipath_qp_table *qpt)
276 {
277         unsigned long flags;
278         struct ipath_qp *qp, *nqp;
279         u32 n;
280
281         for (n = 0; n < qpt->max; n++) {
282                 spin_lock_irqsave(&qpt->lock, flags);
283                 qp = qpt->table[n];
284                 qpt->table[n] = NULL;
285                 spin_unlock_irqrestore(&qpt->lock, flags);
286
287                 while (qp) {
288                         nqp = qp->next;
289                         free_qpn(qpt, qp->ibqp.qp_num);
290                         if (!atomic_dec_and_test(&qp->refcount) ||
291                             !ipath_destroy_qp(&qp->ibqp))
292                                 ipath_dbg("QP memory leak!\n");
293                         qp = nqp;
294                 }
295         }
296
297         for (n = 0; n < ARRAY_SIZE(qpt->map); n++) {
298                 if (qpt->map[n].page)
299                         free_page((unsigned long)qpt->map[n].page);
300         }
301 }
302
303 /**
304  * ipath_lookup_qpn - return the QP with the given QPN
305  * @qpt: the QP table
306  * @qpn: the QP number to look up
307  *
308  * The caller is responsible for decrementing the QP reference count
309  * when done.
310  */
311 struct ipath_qp *ipath_lookup_qpn(struct ipath_qp_table *qpt, u32 qpn)
312 {
313         unsigned long flags;
314         struct ipath_qp *qp;
315
316         spin_lock_irqsave(&qpt->lock, flags);
317
318         for (qp = qpt->table[qpn % qpt->max]; qp; qp = qp->next) {
319                 if (qp->ibqp.qp_num == qpn) {
320                         atomic_inc(&qp->refcount);
321                         break;
322                 }
323         }
324
325         spin_unlock_irqrestore(&qpt->lock, flags);
326         return qp;
327 }
328
329 /**
330  * ipath_reset_qp - initialize the QP state to the reset state
331  * @qp: the QP to reset
332  * @type: the QP type
333  */
334 static void ipath_reset_qp(struct ipath_qp *qp, enum ib_qp_type type)
335 {
336         qp->remote_qpn = 0;
337         qp->qkey = 0;
338         qp->qp_access_flags = 0;
339         qp->s_busy = 0;
340         qp->s_flags &= IPATH_S_SIGNAL_REQ_WR;
341         qp->s_hdrwords = 0;
342         qp->s_wqe = NULL;
343         qp->s_psn = 0;
344         qp->r_psn = 0;
345         qp->r_msn = 0;
346         if (type == IB_QPT_RC) {
347                 qp->s_state = IB_OPCODE_RC_SEND_LAST;
348                 qp->r_state = IB_OPCODE_RC_SEND_LAST;
349         } else {
350                 qp->s_state = IB_OPCODE_UC_SEND_LAST;
351                 qp->r_state = IB_OPCODE_UC_SEND_LAST;
352         }
353         qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
354         qp->r_nak_state = 0;
355         qp->r_wrid_valid = 0;
356         qp->s_rnr_timeout = 0;
357         qp->s_head = 0;
358         qp->s_tail = 0;
359         qp->s_cur = 0;
360         qp->s_last = 0;
361         qp->s_ssn = 1;
362         qp->s_lsn = 0;
363         qp->s_wait_credit = 0;
364         memset(qp->s_ack_queue, 0, sizeof(qp->s_ack_queue));
365         qp->r_head_ack_queue = 0;
366         qp->s_tail_ack_queue = 0;
367         qp->s_num_rd_atomic = 0;
368         if (qp->r_rq.wq) {
369                 qp->r_rq.wq->head = 0;
370                 qp->r_rq.wq->tail = 0;
371         }
372         qp->r_reuse_sge = 0;
373 }
374
375 /**
376  * ipath_error_qp - put a QP into an error state
377  * @qp: the QP to put into an error state
378  * @err: the receive completion error to signal if a RWQE is active
379  *
380  * Flushes both send and receive work queues.
381  * Returns true if last WQE event should be generated.
382  * The QP s_lock should be held and interrupts disabled.
383  */
384
385 int ipath_error_qp(struct ipath_qp *qp, enum ib_wc_status err)
386 {
387         struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
388         struct ib_wc wc;
389         int ret = 0;
390
391         ipath_dbg("QP%d/%d in error state (%d)\n",
392                   qp->ibqp.qp_num, qp->remote_qpn, err);
393
394         spin_lock(&dev->pending_lock);
395         if (!list_empty(&qp->timerwait))
396                 list_del_init(&qp->timerwait);
397         if (!list_empty(&qp->piowait))
398                 list_del_init(&qp->piowait);
399         spin_unlock(&dev->pending_lock);
400
401         wc.vendor_err = 0;
402         wc.byte_len = 0;
403         wc.imm_data = 0;
404         wc.qp = &qp->ibqp;
405         wc.src_qp = 0;
406         wc.wc_flags = 0;
407         wc.pkey_index = 0;
408         wc.slid = 0;
409         wc.sl = 0;
410         wc.dlid_path_bits = 0;
411         wc.port_num = 0;
412         if (qp->r_wrid_valid) {
413                 qp->r_wrid_valid = 0;
414                 wc.wr_id = qp->r_wr_id;
415                 wc.opcode = IB_WC_RECV;
416                 wc.status = err;
417                 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
418         }
419         wc.status = IB_WC_WR_FLUSH_ERR;
420
421         while (qp->s_last != qp->s_head) {
422                 struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
423
424                 wc.wr_id = wqe->wr.wr_id;
425                 wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
426                 if (++qp->s_last >= qp->s_size)
427                         qp->s_last = 0;
428                 ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 1);
429         }
430         qp->s_cur = qp->s_tail = qp->s_head;
431         qp->s_hdrwords = 0;
432         qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
433
434         if (qp->r_rq.wq) {
435                 struct ipath_rwq *wq;
436                 u32 head;
437                 u32 tail;
438
439                 spin_lock(&qp->r_rq.lock);
440
441                 /* sanity check pointers before trusting them */
442                 wq = qp->r_rq.wq;
443                 head = wq->head;
444                 if (head >= qp->r_rq.size)
445                         head = 0;
446                 tail = wq->tail;
447                 if (tail >= qp->r_rq.size)
448                         tail = 0;
449                 wc.opcode = IB_WC_RECV;
450                 while (tail != head) {
451                         wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
452                         if (++tail >= qp->r_rq.size)
453                                 tail = 0;
454                         ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
455                 }
456                 wq->tail = tail;
457
458                 spin_unlock(&qp->r_rq.lock);
459         } else if (qp->ibqp.event_handler)
460                 ret = 1;
461
462         return ret;
463 }
464
465 /**
466  * ipath_modify_qp - modify the attributes of a queue pair
467  * @ibqp: the queue pair who's attributes we're modifying
468  * @attr: the new attributes
469  * @attr_mask: the mask of attributes to modify
470  * @udata: user data for ipathverbs.so
471  *
472  * Returns 0 on success, otherwise returns an errno.
473  */
474 int ipath_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
475                     int attr_mask, struct ib_udata *udata)
476 {
477         struct ipath_ibdev *dev = to_idev(ibqp->device);
478         struct ipath_qp *qp = to_iqp(ibqp);
479         enum ib_qp_state cur_state, new_state;
480         unsigned long flags;
481         int lastwqe = 0;
482         int ret;
483
484         spin_lock_irqsave(&qp->s_lock, flags);
485
486         cur_state = attr_mask & IB_QP_CUR_STATE ?
487                 attr->cur_qp_state : qp->state;
488         new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
489
490         if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
491                                 attr_mask))
492                 goto inval;
493
494         if (attr_mask & IB_QP_AV) {
495                 if (attr->ah_attr.dlid == 0 ||
496                     attr->ah_attr.dlid >= IPATH_MULTICAST_LID_BASE)
497                         goto inval;
498
499                 if ((attr->ah_attr.ah_flags & IB_AH_GRH) &&
500                     (attr->ah_attr.grh.sgid_index > 1))
501                         goto inval;
502         }
503
504         if (attr_mask & IB_QP_PKEY_INDEX)
505                 if (attr->pkey_index >= ipath_get_npkeys(dev->dd))
506                         goto inval;
507
508         if (attr_mask & IB_QP_MIN_RNR_TIMER)
509                 if (attr->min_rnr_timer > 31)
510                         goto inval;
511
512         if (attr_mask & IB_QP_PORT)
513                 if (attr->port_num == 0 ||
514                     attr->port_num > ibqp->device->phys_port_cnt)
515                         goto inval;
516
517         /*
518          * don't allow invalid Path MTU values or greater than 2048
519          * unless we are configured for a 4KB MTU
520          */
521         if ((attr_mask & IB_QP_PATH_MTU) &&
522                 (ib_mtu_enum_to_int(attr->path_mtu) == -1 ||
523                 (attr->path_mtu > IB_MTU_2048 && !ipath_mtu4096)))
524                 goto inval;
525
526         if (attr_mask & IB_QP_PATH_MIG_STATE)
527                 if (attr->path_mig_state != IB_MIG_MIGRATED &&
528                     attr->path_mig_state != IB_MIG_REARM)
529                         goto inval;
530
531         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
532                 if (attr->max_dest_rd_atomic > IPATH_MAX_RDMA_ATOMIC)
533                         goto inval;
534
535         switch (new_state) {
536         case IB_QPS_RESET:
537                 ipath_reset_qp(qp, ibqp->qp_type);
538                 break;
539
540         case IB_QPS_ERR:
541                 lastwqe = ipath_error_qp(qp, IB_WC_WR_FLUSH_ERR);
542                 break;
543
544         default:
545                 break;
546
547         }
548
549         if (attr_mask & IB_QP_PKEY_INDEX)
550                 qp->s_pkey_index = attr->pkey_index;
551
552         if (attr_mask & IB_QP_DEST_QPN)
553                 qp->remote_qpn = attr->dest_qp_num;
554
555         if (attr_mask & IB_QP_SQ_PSN) {
556                 qp->s_psn = qp->s_next_psn = attr->sq_psn;
557                 qp->s_last_psn = qp->s_next_psn - 1;
558         }
559
560         if (attr_mask & IB_QP_RQ_PSN)
561                 qp->r_psn = attr->rq_psn;
562
563         if (attr_mask & IB_QP_ACCESS_FLAGS)
564                 qp->qp_access_flags = attr->qp_access_flags;
565
566         if (attr_mask & IB_QP_AV)
567                 qp->remote_ah_attr = attr->ah_attr;
568
569         if (attr_mask & IB_QP_PATH_MTU)
570                 qp->path_mtu = attr->path_mtu;
571
572         if (attr_mask & IB_QP_RETRY_CNT)
573                 qp->s_retry = qp->s_retry_cnt = attr->retry_cnt;
574
575         if (attr_mask & IB_QP_RNR_RETRY) {
576                 qp->s_rnr_retry = attr->rnr_retry;
577                 if (qp->s_rnr_retry > 7)
578                         qp->s_rnr_retry = 7;
579                 qp->s_rnr_retry_cnt = qp->s_rnr_retry;
580         }
581
582         if (attr_mask & IB_QP_MIN_RNR_TIMER)
583                 qp->r_min_rnr_timer = attr->min_rnr_timer;
584
585         if (attr_mask & IB_QP_TIMEOUT)
586                 qp->timeout = attr->timeout;
587
588         if (attr_mask & IB_QP_QKEY)
589                 qp->qkey = attr->qkey;
590
591         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
592                 qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
593
594         if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
595                 qp->s_max_rd_atomic = attr->max_rd_atomic;
596
597         qp->state = new_state;
598         spin_unlock_irqrestore(&qp->s_lock, flags);
599
600         if (lastwqe) {
601                 struct ib_event ev;
602
603                 ev.device = qp->ibqp.device;
604                 ev.element.qp = &qp->ibqp;
605                 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
606                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
607         }
608         ret = 0;
609         goto bail;
610
611 inval:
612         spin_unlock_irqrestore(&qp->s_lock, flags);
613         ret = -EINVAL;
614
615 bail:
616         return ret;
617 }
618
619 int ipath_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
620                    int attr_mask, struct ib_qp_init_attr *init_attr)
621 {
622         struct ipath_qp *qp = to_iqp(ibqp);
623
624         attr->qp_state = qp->state;
625         attr->cur_qp_state = attr->qp_state;
626         attr->path_mtu = qp->path_mtu;
627         attr->path_mig_state = 0;
628         attr->qkey = qp->qkey;
629         attr->rq_psn = qp->r_psn;
630         attr->sq_psn = qp->s_next_psn;
631         attr->dest_qp_num = qp->remote_qpn;
632         attr->qp_access_flags = qp->qp_access_flags;
633         attr->cap.max_send_wr = qp->s_size - 1;
634         attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
635         attr->cap.max_send_sge = qp->s_max_sge;
636         attr->cap.max_recv_sge = qp->r_rq.max_sge;
637         attr->cap.max_inline_data = 0;
638         attr->ah_attr = qp->remote_ah_attr;
639         memset(&attr->alt_ah_attr, 0, sizeof(attr->alt_ah_attr));
640         attr->pkey_index = qp->s_pkey_index;
641         attr->alt_pkey_index = 0;
642         attr->en_sqd_async_notify = 0;
643         attr->sq_draining = 0;
644         attr->max_rd_atomic = qp->s_max_rd_atomic;
645         attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
646         attr->min_rnr_timer = qp->r_min_rnr_timer;
647         attr->port_num = 1;
648         attr->timeout = qp->timeout;
649         attr->retry_cnt = qp->s_retry_cnt;
650         attr->rnr_retry = qp->s_rnr_retry_cnt;
651         attr->alt_port_num = 0;
652         attr->alt_timeout = 0;
653
654         init_attr->event_handler = qp->ibqp.event_handler;
655         init_attr->qp_context = qp->ibqp.qp_context;
656         init_attr->send_cq = qp->ibqp.send_cq;
657         init_attr->recv_cq = qp->ibqp.recv_cq;
658         init_attr->srq = qp->ibqp.srq;
659         init_attr->cap = attr->cap;
660         if (qp->s_flags & IPATH_S_SIGNAL_REQ_WR)
661                 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
662         else
663                 init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
664         init_attr->qp_type = qp->ibqp.qp_type;
665         init_attr->port_num = 1;
666         return 0;
667 }
668
669 /**
670  * ipath_compute_aeth - compute the AETH (syndrome + MSN)
671  * @qp: the queue pair to compute the AETH for
672  *
673  * Returns the AETH.
674  */
675 __be32 ipath_compute_aeth(struct ipath_qp *qp)
676 {
677         u32 aeth = qp->r_msn & IPATH_MSN_MASK;
678
679         if (qp->ibqp.srq) {
680                 /*
681                  * Shared receive queues don't generate credits.
682                  * Set the credit field to the invalid value.
683                  */
684                 aeth |= IPATH_AETH_CREDIT_INVAL << IPATH_AETH_CREDIT_SHIFT;
685         } else {
686                 u32 min, max, x;
687                 u32 credits;
688                 struct ipath_rwq *wq = qp->r_rq.wq;
689                 u32 head;
690                 u32 tail;
691
692                 /* sanity check pointers before trusting them */
693                 head = wq->head;
694                 if (head >= qp->r_rq.size)
695                         head = 0;
696                 tail = wq->tail;
697                 if (tail >= qp->r_rq.size)
698                         tail = 0;
699                 /*
700                  * Compute the number of credits available (RWQEs).
701                  * XXX Not holding the r_rq.lock here so there is a small
702                  * chance that the pair of reads are not atomic.
703                  */
704                 credits = head - tail;
705                 if ((int)credits < 0)
706                         credits += qp->r_rq.size;
707                 /*
708                  * Binary search the credit table to find the code to
709                  * use.
710                  */
711                 min = 0;
712                 max = 31;
713                 for (;;) {
714                         x = (min + max) / 2;
715                         if (credit_table[x] == credits)
716                                 break;
717                         if (credit_table[x] > credits)
718                                 max = x;
719                         else if (min == x)
720                                 break;
721                         else
722                                 min = x;
723                 }
724                 aeth |= x << IPATH_AETH_CREDIT_SHIFT;
725         }
726         return cpu_to_be32(aeth);
727 }
728
729 /**
730  * ipath_create_qp - create a queue pair for a device
731  * @ibpd: the protection domain who's device we create the queue pair for
732  * @init_attr: the attributes of the queue pair
733  * @udata: unused by InfiniPath
734  *
735  * Returns the queue pair on success, otherwise returns an errno.
736  *
737  * Called by the ib_create_qp() core verbs function.
738  */
739 struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
740                               struct ib_qp_init_attr *init_attr,
741                               struct ib_udata *udata)
742 {
743         struct ipath_qp *qp;
744         int err;
745         struct ipath_swqe *swq = NULL;
746         struct ipath_ibdev *dev;
747         size_t sz;
748         struct ib_qp *ret;
749
750         if (init_attr->cap.max_send_sge > ib_ipath_max_sges ||
751             init_attr->cap.max_recv_sge > ib_ipath_max_sges ||
752             init_attr->cap.max_send_wr > ib_ipath_max_qp_wrs ||
753             init_attr->cap.max_recv_wr > ib_ipath_max_qp_wrs) {
754                 ret = ERR_PTR(-ENOMEM);
755                 goto bail;
756         }
757
758         if (init_attr->cap.max_send_sge +
759             init_attr->cap.max_recv_sge +
760             init_attr->cap.max_send_wr +
761             init_attr->cap.max_recv_wr == 0) {
762                 ret = ERR_PTR(-EINVAL);
763                 goto bail;
764         }
765
766         switch (init_attr->qp_type) {
767         case IB_QPT_UC:
768         case IB_QPT_RC:
769         case IB_QPT_UD:
770         case IB_QPT_SMI:
771         case IB_QPT_GSI:
772                 sz = sizeof(struct ipath_sge) *
773                         init_attr->cap.max_send_sge +
774                         sizeof(struct ipath_swqe);
775                 swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
776                 if (swq == NULL) {
777                         ret = ERR_PTR(-ENOMEM);
778                         goto bail;
779                 }
780                 sz = sizeof(*qp);
781                 if (init_attr->srq) {
782                         struct ipath_srq *srq = to_isrq(init_attr->srq);
783
784                         sz += sizeof(*qp->r_sg_list) *
785                                 srq->rq.max_sge;
786                 } else
787                         sz += sizeof(*qp->r_sg_list) *
788                                 init_attr->cap.max_recv_sge;
789                 qp = kmalloc(sz, GFP_KERNEL);
790                 if (!qp) {
791                         ret = ERR_PTR(-ENOMEM);
792                         goto bail_swq;
793                 }
794                 if (init_attr->srq) {
795                         sz = 0;
796                         qp->r_rq.size = 0;
797                         qp->r_rq.max_sge = 0;
798                         qp->r_rq.wq = NULL;
799                         init_attr->cap.max_recv_wr = 0;
800                         init_attr->cap.max_recv_sge = 0;
801                 } else {
802                         qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
803                         qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
804                         sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
805                                 sizeof(struct ipath_rwqe);
806                         qp->r_rq.wq = vmalloc_user(sizeof(struct ipath_rwq) +
807                                               qp->r_rq.size * sz);
808                         if (!qp->r_rq.wq) {
809                                 ret = ERR_PTR(-ENOMEM);
810                                 goto bail_qp;
811                         }
812                 }
813
814                 /*
815                  * ib_create_qp() will initialize qp->ibqp
816                  * except for qp->ibqp.qp_num.
817                  */
818                 spin_lock_init(&qp->s_lock);
819                 spin_lock_init(&qp->r_rq.lock);
820                 atomic_set(&qp->refcount, 0);
821                 init_waitqueue_head(&qp->wait);
822                 tasklet_init(&qp->s_task, ipath_do_send, (unsigned long)qp);
823                 INIT_LIST_HEAD(&qp->piowait);
824                 INIT_LIST_HEAD(&qp->timerwait);
825                 qp->state = IB_QPS_RESET;
826                 qp->s_wq = swq;
827                 qp->s_size = init_attr->cap.max_send_wr + 1;
828                 qp->s_max_sge = init_attr->cap.max_send_sge;
829                 if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
830                         qp->s_flags = IPATH_S_SIGNAL_REQ_WR;
831                 else
832                         qp->s_flags = 0;
833                 dev = to_idev(ibpd->device);
834                 err = ipath_alloc_qpn(&dev->qp_table, qp,
835                                       init_attr->qp_type);
836                 if (err) {
837                         ret = ERR_PTR(err);
838                         vfree(qp->r_rq.wq);
839                         goto bail_qp;
840                 }
841                 qp->ip = NULL;
842                 ipath_reset_qp(qp, init_attr->qp_type);
843                 break;
844
845         default:
846                 /* Don't support raw QPs */
847                 ret = ERR_PTR(-ENOSYS);
848                 goto bail;
849         }
850
851         init_attr->cap.max_inline_data = 0;
852
853         /*
854          * Return the address of the RWQ as the offset to mmap.
855          * See ipath_mmap() for details.
856          */
857         if (udata && udata->outlen >= sizeof(__u64)) {
858                 if (!qp->r_rq.wq) {
859                         __u64 offset = 0;
860
861                         err = ib_copy_to_udata(udata, &offset,
862                                                sizeof(offset));
863                         if (err) {
864                                 ret = ERR_PTR(err);
865                                 goto bail_ip;
866                         }
867                 } else {
868                         u32 s = sizeof(struct ipath_rwq) +
869                                 qp->r_rq.size * sz;
870
871                         qp->ip =
872                             ipath_create_mmap_info(dev, s,
873                                                    ibpd->uobject->context,
874                                                    qp->r_rq.wq);
875                         if (!qp->ip) {
876                                 ret = ERR_PTR(-ENOMEM);
877                                 goto bail_ip;
878                         }
879
880                         err = ib_copy_to_udata(udata, &(qp->ip->offset),
881                                                sizeof(qp->ip->offset));
882                         if (err) {
883                                 ret = ERR_PTR(err);
884                                 goto bail_ip;
885                         }
886                 }
887         }
888
889         spin_lock(&dev->n_qps_lock);
890         if (dev->n_qps_allocated == ib_ipath_max_qps) {
891                 spin_unlock(&dev->n_qps_lock);
892                 ret = ERR_PTR(-ENOMEM);
893                 goto bail_ip;
894         }
895
896         dev->n_qps_allocated++;
897         spin_unlock(&dev->n_qps_lock);
898
899         if (qp->ip) {
900                 spin_lock_irq(&dev->pending_lock);
901                 list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
902                 spin_unlock_irq(&dev->pending_lock);
903         }
904
905         ret = &qp->ibqp;
906         goto bail;
907
908 bail_ip:
909         if (qp->ip)
910                 kref_put(&qp->ip->ref, ipath_release_mmap_info);
911         else
912                 vfree(qp->r_rq.wq);
913         ipath_free_qp(&dev->qp_table, qp);
914 bail_qp:
915         kfree(qp);
916 bail_swq:
917         vfree(swq);
918 bail:
919         return ret;
920 }
921
922 /**
923  * ipath_destroy_qp - destroy a queue pair
924  * @ibqp: the queue pair to destroy
925  *
926  * Returns 0 on success.
927  *
928  * Note that this can be called while the QP is actively sending or
929  * receiving!
930  */
931 int ipath_destroy_qp(struct ib_qp *ibqp)
932 {
933         struct ipath_qp *qp = to_iqp(ibqp);
934         struct ipath_ibdev *dev = to_idev(ibqp->device);
935         unsigned long flags;
936
937         spin_lock_irqsave(&qp->s_lock, flags);
938         qp->state = IB_QPS_ERR;
939         spin_unlock_irqrestore(&qp->s_lock, flags);
940         spin_lock(&dev->n_qps_lock);
941         dev->n_qps_allocated--;
942         spin_unlock(&dev->n_qps_lock);
943
944         /* Stop the sending tasklet. */
945         tasklet_kill(&qp->s_task);
946
947         /* Make sure the QP isn't on the timeout list. */
948         spin_lock_irqsave(&dev->pending_lock, flags);
949         if (!list_empty(&qp->timerwait))
950                 list_del_init(&qp->timerwait);
951         if (!list_empty(&qp->piowait))
952                 list_del_init(&qp->piowait);
953         spin_unlock_irqrestore(&dev->pending_lock, flags);
954
955         /*
956          * Make sure that the QP is not in the QPN table so receive
957          * interrupts will discard packets for this QP.  XXX Also remove QP
958          * from multicast table.
959          */
960         if (atomic_read(&qp->refcount) != 0)
961                 ipath_free_qp(&dev->qp_table, qp);
962
963         if (qp->ip)
964                 kref_put(&qp->ip->ref, ipath_release_mmap_info);
965         else
966                 vfree(qp->r_rq.wq);
967         vfree(qp->s_wq);
968         kfree(qp);
969         return 0;
970 }
971
972 /**
973  * ipath_init_qp_table - initialize the QP table for a device
974  * @idev: the device who's QP table we're initializing
975  * @size: the size of the QP table
976  *
977  * Returns 0 on success, otherwise returns an errno.
978  */
979 int ipath_init_qp_table(struct ipath_ibdev *idev, int size)
980 {
981         int i;
982         int ret;
983
984         idev->qp_table.last = 1;        /* QPN 0 and 1 are special. */
985         idev->qp_table.max = size;
986         idev->qp_table.nmaps = 1;
987         idev->qp_table.table = kzalloc(size * sizeof(*idev->qp_table.table),
988                                        GFP_KERNEL);
989         if (idev->qp_table.table == NULL) {
990                 ret = -ENOMEM;
991                 goto bail;
992         }
993
994         for (i = 0; i < ARRAY_SIZE(idev->qp_table.map); i++) {
995                 atomic_set(&idev->qp_table.map[i].n_free, BITS_PER_PAGE);
996                 idev->qp_table.map[i].page = NULL;
997         }
998
999         ret = 0;
1000
1001 bail:
1002         return ret;
1003 }
1004
1005 /**
1006  * ipath_sqerror_qp - put a QP's send queue into an error state
1007  * @qp: QP who's send queue will be put into an error state
1008  * @wc: the WC responsible for putting the QP in this state
1009  *
1010  * Flushes the send work queue.
1011  * The QP s_lock should be held and interrupts disabled.
1012  */
1013
1014 void ipath_sqerror_qp(struct ipath_qp *qp, struct ib_wc *wc)
1015 {
1016         struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
1017         struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
1018
1019         ipath_dbg("Send queue error on QP%d/%d: err: %d\n",
1020                   qp->ibqp.qp_num, qp->remote_qpn, wc->status);
1021
1022         spin_lock(&dev->pending_lock);
1023         if (!list_empty(&qp->timerwait))
1024                 list_del_init(&qp->timerwait);
1025         if (!list_empty(&qp->piowait))
1026                 list_del_init(&qp->piowait);
1027         spin_unlock(&dev->pending_lock);
1028
1029         ipath_cq_enter(to_icq(qp->ibqp.send_cq), wc, 1);
1030         if (++qp->s_last >= qp->s_size)
1031                 qp->s_last = 0;
1032
1033         wc->status = IB_WC_WR_FLUSH_ERR;
1034
1035         while (qp->s_last != qp->s_head) {
1036                 wqe = get_swqe_ptr(qp, qp->s_last);
1037                 wc->wr_id = wqe->wr.wr_id;
1038                 wc->opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
1039                 ipath_cq_enter(to_icq(qp->ibqp.send_cq), wc, 1);
1040                 if (++qp->s_last >= qp->s_size)
1041                         qp->s_last = 0;
1042         }
1043         qp->s_cur = qp->s_tail = qp->s_head;
1044         qp->state = IB_QPS_SQE;
1045 }
1046
1047 /**
1048  * ipath_get_credit - flush the send work queue of a QP
1049  * @qp: the qp who's send work queue to flush
1050  * @aeth: the Acknowledge Extended Transport Header
1051  *
1052  * The QP s_lock should be held.
1053  */
1054 void ipath_get_credit(struct ipath_qp *qp, u32 aeth)
1055 {
1056         u32 credit = (aeth >> IPATH_AETH_CREDIT_SHIFT) & IPATH_AETH_CREDIT_MASK;
1057
1058         /*
1059          * If the credit is invalid, we can send
1060          * as many packets as we like.  Otherwise, we have to
1061          * honor the credit field.
1062          */
1063         if (credit == IPATH_AETH_CREDIT_INVAL)
1064                 qp->s_lsn = (u32) -1;
1065         else if (qp->s_lsn != (u32) -1) {
1066                 /* Compute new LSN (i.e., MSN + credit) */
1067                 credit = (aeth + credit_table[credit]) & IPATH_MSN_MASK;
1068                 if (ipath_cmp24(credit, qp->s_lsn) > 0)
1069                         qp->s_lsn = credit;
1070         }
1071
1072         /* Restart sending if it was blocked due to lack of credits. */
1073         if (qp->s_cur != qp->s_head &&
1074             (qp->s_lsn == (u32) -1 ||
1075              ipath_cmp24(get_swqe_ptr(qp, qp->s_cur)->ssn,
1076                          qp->s_lsn + 1) <= 0))
1077                 tasklet_hi_schedule(&qp->s_task);
1078 }