Merge branch 'sh/smp'
[pandora-kernel.git] / drivers / infiniband / hw / ipath / ipath_qp.c
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/err.h>
35 #include <linux/sched.h>
36 #include <linux/slab.h>
37 #include <linux/vmalloc.h>
38
39 #include "ipath_verbs.h"
40 #include "ipath_kernel.h"
41
42 #define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
43 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
44 #define mk_qpn(qpt, map, off)   (((map) - (qpt)->map) * BITS_PER_PAGE + \
45                                  (off))
46 #define find_next_offset(map, off) find_next_zero_bit((map)->page, \
47                                                       BITS_PER_PAGE, off)
48
49 /*
50  * Convert the AETH credit code into the number of credits.
51  */
52 static u32 credit_table[31] = {
53         0,                      /* 0 */
54         1,                      /* 1 */
55         2,                      /* 2 */
56         3,                      /* 3 */
57         4,                      /* 4 */
58         6,                      /* 5 */
59         8,                      /* 6 */
60         12,                     /* 7 */
61         16,                     /* 8 */
62         24,                     /* 9 */
63         32,                     /* A */
64         48,                     /* B */
65         64,                     /* C */
66         96,                     /* D */
67         128,                    /* E */
68         192,                    /* F */
69         256,                    /* 10 */
70         384,                    /* 11 */
71         512,                    /* 12 */
72         768,                    /* 13 */
73         1024,                   /* 14 */
74         1536,                   /* 15 */
75         2048,                   /* 16 */
76         3072,                   /* 17 */
77         4096,                   /* 18 */
78         6144,                   /* 19 */
79         8192,                   /* 1A */
80         12288,                  /* 1B */
81         16384,                  /* 1C */
82         24576,                  /* 1D */
83         32768                   /* 1E */
84 };
85
86
87 static void get_map_page(struct ipath_qp_table *qpt, struct qpn_map *map)
88 {
89         unsigned long page = get_zeroed_page(GFP_KERNEL);
90         unsigned long flags;
91
92         /*
93          * Free the page if someone raced with us installing it.
94          */
95
96         spin_lock_irqsave(&qpt->lock, flags);
97         if (map->page)
98                 free_page(page);
99         else
100                 map->page = (void *)page;
101         spin_unlock_irqrestore(&qpt->lock, flags);
102 }
103
104
105 static int alloc_qpn(struct ipath_qp_table *qpt, enum ib_qp_type type)
106 {
107         u32 i, offset, max_scan, qpn;
108         struct qpn_map *map;
109         u32 ret = -1;
110
111         if (type == IB_QPT_SMI)
112                 ret = 0;
113         else if (type == IB_QPT_GSI)
114                 ret = 1;
115
116         if (ret != -1) {
117                 map = &qpt->map[0];
118                 if (unlikely(!map->page)) {
119                         get_map_page(qpt, map);
120                         if (unlikely(!map->page)) {
121                                 ret = -ENOMEM;
122                                 goto bail;
123                         }
124                 }
125                 if (!test_and_set_bit(ret, map->page))
126                         atomic_dec(&map->n_free);
127                 else
128                         ret = -EBUSY;
129                 goto bail;
130         }
131
132         qpn = qpt->last + 1;
133         if (qpn >= QPN_MAX)
134                 qpn = 2;
135         offset = qpn & BITS_PER_PAGE_MASK;
136         map = &qpt->map[qpn / BITS_PER_PAGE];
137         max_scan = qpt->nmaps - !offset;
138         for (i = 0;;) {
139                 if (unlikely(!map->page)) {
140                         get_map_page(qpt, map);
141                         if (unlikely(!map->page))
142                                 break;
143                 }
144                 if (likely(atomic_read(&map->n_free))) {
145                         do {
146                                 if (!test_and_set_bit(offset, map->page)) {
147                                         atomic_dec(&map->n_free);
148                                         qpt->last = qpn;
149                                         ret = qpn;
150                                         goto bail;
151                                 }
152                                 offset = find_next_offset(map, offset);
153                                 qpn = mk_qpn(qpt, map, offset);
154                                 /*
155                                  * This test differs from alloc_pidmap().
156                                  * If find_next_offset() does find a zero
157                                  * bit, we don't need to check for QPN
158                                  * wrapping around past our starting QPN.
159                                  * We just need to be sure we don't loop
160                                  * forever.
161                                  */
162                         } while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
163                 }
164                 /*
165                  * In order to keep the number of pages allocated to a
166                  * minimum, we scan the all existing pages before increasing
167                  * the size of the bitmap table.
168                  */
169                 if (++i > max_scan) {
170                         if (qpt->nmaps == QPNMAP_ENTRIES)
171                                 break;
172                         map = &qpt->map[qpt->nmaps++];
173                         offset = 0;
174                 } else if (map < &qpt->map[qpt->nmaps]) {
175                         ++map;
176                         offset = 0;
177                 } else {
178                         map = &qpt->map[0];
179                         offset = 2;
180                 }
181                 qpn = mk_qpn(qpt, map, offset);
182         }
183
184         ret = -ENOMEM;
185
186 bail:
187         return ret;
188 }
189
190 static void free_qpn(struct ipath_qp_table *qpt, u32 qpn)
191 {
192         struct qpn_map *map;
193
194         map = qpt->map + qpn / BITS_PER_PAGE;
195         if (map->page)
196                 clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
197         atomic_inc(&map->n_free);
198 }
199
200 /**
201  * ipath_alloc_qpn - allocate a QP number
202  * @qpt: the QP table
203  * @qp: the QP
204  * @type: the QP type (IB_QPT_SMI and IB_QPT_GSI are special)
205  *
206  * Allocate the next available QPN and put the QP into the hash table.
207  * The hash table holds a reference to the QP.
208  */
209 static int ipath_alloc_qpn(struct ipath_qp_table *qpt, struct ipath_qp *qp,
210                            enum ib_qp_type type)
211 {
212         unsigned long flags;
213         int ret;
214
215         ret = alloc_qpn(qpt, type);
216         if (ret < 0)
217                 goto bail;
218         qp->ibqp.qp_num = ret;
219
220         /* Add the QP to the hash table. */
221         spin_lock_irqsave(&qpt->lock, flags);
222
223         ret %= qpt->max;
224         qp->next = qpt->table[ret];
225         qpt->table[ret] = qp;
226         atomic_inc(&qp->refcount);
227
228         spin_unlock_irqrestore(&qpt->lock, flags);
229         ret = 0;
230
231 bail:
232         return ret;
233 }
234
235 /**
236  * ipath_free_qp - remove a QP from the QP table
237  * @qpt: the QP table
238  * @qp: the QP to remove
239  *
240  * Remove the QP from the table so it can't be found asynchronously by
241  * the receive interrupt routine.
242  */
243 static void ipath_free_qp(struct ipath_qp_table *qpt, struct ipath_qp *qp)
244 {
245         struct ipath_qp *q, **qpp;
246         unsigned long flags;
247
248         spin_lock_irqsave(&qpt->lock, flags);
249
250         /* Remove QP from the hash table. */
251         qpp = &qpt->table[qp->ibqp.qp_num % qpt->max];
252         for (; (q = *qpp) != NULL; qpp = &q->next) {
253                 if (q == qp) {
254                         *qpp = qp->next;
255                         qp->next = NULL;
256                         atomic_dec(&qp->refcount);
257                         break;
258                 }
259         }
260
261         spin_unlock_irqrestore(&qpt->lock, flags);
262 }
263
264 /**
265  * ipath_free_all_qps - check for QPs still in use
266  * @qpt: the QP table to empty
267  *
268  * There should not be any QPs still in use.
269  * Free memory for table.
270  */
271 unsigned ipath_free_all_qps(struct ipath_qp_table *qpt)
272 {
273         unsigned long flags;
274         struct ipath_qp *qp;
275         u32 n, qp_inuse = 0;
276
277         spin_lock_irqsave(&qpt->lock, flags);
278         for (n = 0; n < qpt->max; n++) {
279                 qp = qpt->table[n];
280                 qpt->table[n] = NULL;
281
282                 for (; qp; qp = qp->next)
283                         qp_inuse++;
284         }
285         spin_unlock_irqrestore(&qpt->lock, flags);
286
287         for (n = 0; n < ARRAY_SIZE(qpt->map); n++)
288                 if (qpt->map[n].page)
289                         free_page((unsigned long) qpt->map[n].page);
290         return qp_inuse;
291 }
292
293 /**
294  * ipath_lookup_qpn - return the QP with the given QPN
295  * @qpt: the QP table
296  * @qpn: the QP number to look up
297  *
298  * The caller is responsible for decrementing the QP reference count
299  * when done.
300  */
301 struct ipath_qp *ipath_lookup_qpn(struct ipath_qp_table *qpt, u32 qpn)
302 {
303         unsigned long flags;
304         struct ipath_qp *qp;
305
306         spin_lock_irqsave(&qpt->lock, flags);
307
308         for (qp = qpt->table[qpn % qpt->max]; qp; qp = qp->next) {
309                 if (qp->ibqp.qp_num == qpn) {
310                         atomic_inc(&qp->refcount);
311                         break;
312                 }
313         }
314
315         spin_unlock_irqrestore(&qpt->lock, flags);
316         return qp;
317 }
318
319 /**
320  * ipath_reset_qp - initialize the QP state to the reset state
321  * @qp: the QP to reset
322  * @type: the QP type
323  */
324 static void ipath_reset_qp(struct ipath_qp *qp, enum ib_qp_type type)
325 {
326         qp->remote_qpn = 0;
327         qp->qkey = 0;
328         qp->qp_access_flags = 0;
329         atomic_set(&qp->s_dma_busy, 0);
330         qp->s_flags &= IPATH_S_SIGNAL_REQ_WR;
331         qp->s_hdrwords = 0;
332         qp->s_wqe = NULL;
333         qp->s_pkt_delay = 0;
334         qp->s_draining = 0;
335         qp->s_psn = 0;
336         qp->r_psn = 0;
337         qp->r_msn = 0;
338         if (type == IB_QPT_RC) {
339                 qp->s_state = IB_OPCODE_RC_SEND_LAST;
340                 qp->r_state = IB_OPCODE_RC_SEND_LAST;
341         } else {
342                 qp->s_state = IB_OPCODE_UC_SEND_LAST;
343                 qp->r_state = IB_OPCODE_UC_SEND_LAST;
344         }
345         qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
346         qp->r_nak_state = 0;
347         qp->r_aflags = 0;
348         qp->r_flags = 0;
349         qp->s_rnr_timeout = 0;
350         qp->s_head = 0;
351         qp->s_tail = 0;
352         qp->s_cur = 0;
353         qp->s_last = 0;
354         qp->s_ssn = 1;
355         qp->s_lsn = 0;
356         memset(qp->s_ack_queue, 0, sizeof(qp->s_ack_queue));
357         qp->r_head_ack_queue = 0;
358         qp->s_tail_ack_queue = 0;
359         qp->s_num_rd_atomic = 0;
360         if (qp->r_rq.wq) {
361                 qp->r_rq.wq->head = 0;
362                 qp->r_rq.wq->tail = 0;
363         }
364 }
365
366 /**
367  * ipath_error_qp - put a QP into the error state
368  * @qp: the QP to put into the error state
369  * @err: the receive completion error to signal if a RWQE is active
370  *
371  * Flushes both send and receive work queues.
372  * Returns true if last WQE event should be generated.
373  * The QP s_lock should be held and interrupts disabled.
374  * If we are already in error state, just return.
375  */
376
377 int ipath_error_qp(struct ipath_qp *qp, enum ib_wc_status err)
378 {
379         struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
380         struct ib_wc wc;
381         int ret = 0;
382
383         if (qp->state == IB_QPS_ERR)
384                 goto bail;
385
386         qp->state = IB_QPS_ERR;
387
388         spin_lock(&dev->pending_lock);
389         if (!list_empty(&qp->timerwait))
390                 list_del_init(&qp->timerwait);
391         if (!list_empty(&qp->piowait))
392                 list_del_init(&qp->piowait);
393         spin_unlock(&dev->pending_lock);
394
395         /* Schedule the sending tasklet to drain the send work queue. */
396         if (qp->s_last != qp->s_head)
397                 ipath_schedule_send(qp);
398
399         memset(&wc, 0, sizeof(wc));
400         wc.qp = &qp->ibqp;
401         wc.opcode = IB_WC_RECV;
402
403         if (test_and_clear_bit(IPATH_R_WRID_VALID, &qp->r_aflags)) {
404                 wc.wr_id = qp->r_wr_id;
405                 wc.status = err;
406                 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
407         }
408         wc.status = IB_WC_WR_FLUSH_ERR;
409
410         if (qp->r_rq.wq) {
411                 struct ipath_rwq *wq;
412                 u32 head;
413                 u32 tail;
414
415                 spin_lock(&qp->r_rq.lock);
416
417                 /* sanity check pointers before trusting them */
418                 wq = qp->r_rq.wq;
419                 head = wq->head;
420                 if (head >= qp->r_rq.size)
421                         head = 0;
422                 tail = wq->tail;
423                 if (tail >= qp->r_rq.size)
424                         tail = 0;
425                 while (tail != head) {
426                         wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
427                         if (++tail >= qp->r_rq.size)
428                                 tail = 0;
429                         ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
430                 }
431                 wq->tail = tail;
432
433                 spin_unlock(&qp->r_rq.lock);
434         } else if (qp->ibqp.event_handler)
435                 ret = 1;
436
437 bail:
438         return ret;
439 }
440
441 /**
442  * ipath_modify_qp - modify the attributes of a queue pair
443  * @ibqp: the queue pair who's attributes we're modifying
444  * @attr: the new attributes
445  * @attr_mask: the mask of attributes to modify
446  * @udata: user data for ipathverbs.so
447  *
448  * Returns 0 on success, otherwise returns an errno.
449  */
450 int ipath_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
451                     int attr_mask, struct ib_udata *udata)
452 {
453         struct ipath_ibdev *dev = to_idev(ibqp->device);
454         struct ipath_qp *qp = to_iqp(ibqp);
455         enum ib_qp_state cur_state, new_state;
456         int lastwqe = 0;
457         int ret;
458
459         spin_lock_irq(&qp->s_lock);
460
461         cur_state = attr_mask & IB_QP_CUR_STATE ?
462                 attr->cur_qp_state : qp->state;
463         new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
464
465         if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
466                                 attr_mask))
467                 goto inval;
468
469         if (attr_mask & IB_QP_AV) {
470                 if (attr->ah_attr.dlid == 0 ||
471                     attr->ah_attr.dlid >= IPATH_MULTICAST_LID_BASE)
472                         goto inval;
473
474                 if ((attr->ah_attr.ah_flags & IB_AH_GRH) &&
475                     (attr->ah_attr.grh.sgid_index > 1))
476                         goto inval;
477         }
478
479         if (attr_mask & IB_QP_PKEY_INDEX)
480                 if (attr->pkey_index >= ipath_get_npkeys(dev->dd))
481                         goto inval;
482
483         if (attr_mask & IB_QP_MIN_RNR_TIMER)
484                 if (attr->min_rnr_timer > 31)
485                         goto inval;
486
487         if (attr_mask & IB_QP_PORT)
488                 if (attr->port_num == 0 ||
489                     attr->port_num > ibqp->device->phys_port_cnt)
490                         goto inval;
491
492         /*
493          * don't allow invalid Path MTU values or greater than 2048
494          * unless we are configured for a 4KB MTU
495          */
496         if ((attr_mask & IB_QP_PATH_MTU) &&
497                 (ib_mtu_enum_to_int(attr->path_mtu) == -1 ||
498                 (attr->path_mtu > IB_MTU_2048 && !ipath_mtu4096)))
499                 goto inval;
500
501         if (attr_mask & IB_QP_PATH_MIG_STATE)
502                 if (attr->path_mig_state != IB_MIG_MIGRATED &&
503                     attr->path_mig_state != IB_MIG_REARM)
504                         goto inval;
505
506         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
507                 if (attr->max_dest_rd_atomic > IPATH_MAX_RDMA_ATOMIC)
508                         goto inval;
509
510         switch (new_state) {
511         case IB_QPS_RESET:
512                 if (qp->state != IB_QPS_RESET) {
513                         qp->state = IB_QPS_RESET;
514                         spin_lock(&dev->pending_lock);
515                         if (!list_empty(&qp->timerwait))
516                                 list_del_init(&qp->timerwait);
517                         if (!list_empty(&qp->piowait))
518                                 list_del_init(&qp->piowait);
519                         spin_unlock(&dev->pending_lock);
520                         qp->s_flags &= ~IPATH_S_ANY_WAIT;
521                         spin_unlock_irq(&qp->s_lock);
522                         /* Stop the sending tasklet */
523                         tasklet_kill(&qp->s_task);
524                         wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
525                         spin_lock_irq(&qp->s_lock);
526                 }
527                 ipath_reset_qp(qp, ibqp->qp_type);
528                 break;
529
530         case IB_QPS_SQD:
531                 qp->s_draining = qp->s_last != qp->s_cur;
532                 qp->state = new_state;
533                 break;
534
535         case IB_QPS_SQE:
536                 if (qp->ibqp.qp_type == IB_QPT_RC)
537                         goto inval;
538                 qp->state = new_state;
539                 break;
540
541         case IB_QPS_ERR:
542                 lastwqe = ipath_error_qp(qp, IB_WC_WR_FLUSH_ERR);
543                 break;
544
545         default:
546                 qp->state = new_state;
547                 break;
548         }
549
550         if (attr_mask & IB_QP_PKEY_INDEX)
551                 qp->s_pkey_index = attr->pkey_index;
552
553         if (attr_mask & IB_QP_DEST_QPN)
554                 qp->remote_qpn = attr->dest_qp_num;
555
556         if (attr_mask & IB_QP_SQ_PSN) {
557                 qp->s_psn = qp->s_next_psn = attr->sq_psn;
558                 qp->s_last_psn = qp->s_next_psn - 1;
559         }
560
561         if (attr_mask & IB_QP_RQ_PSN)
562                 qp->r_psn = attr->rq_psn;
563
564         if (attr_mask & IB_QP_ACCESS_FLAGS)
565                 qp->qp_access_flags = attr->qp_access_flags;
566
567         if (attr_mask & IB_QP_AV) {
568                 qp->remote_ah_attr = attr->ah_attr;
569                 qp->s_dmult = ipath_ib_rate_to_mult(attr->ah_attr.static_rate);
570         }
571
572         if (attr_mask & IB_QP_PATH_MTU)
573                 qp->path_mtu = attr->path_mtu;
574
575         if (attr_mask & IB_QP_RETRY_CNT)
576                 qp->s_retry = qp->s_retry_cnt = attr->retry_cnt;
577
578         if (attr_mask & IB_QP_RNR_RETRY) {
579                 qp->s_rnr_retry = attr->rnr_retry;
580                 if (qp->s_rnr_retry > 7)
581                         qp->s_rnr_retry = 7;
582                 qp->s_rnr_retry_cnt = qp->s_rnr_retry;
583         }
584
585         if (attr_mask & IB_QP_MIN_RNR_TIMER)
586                 qp->r_min_rnr_timer = attr->min_rnr_timer;
587
588         if (attr_mask & IB_QP_TIMEOUT)
589                 qp->timeout = attr->timeout;
590
591         if (attr_mask & IB_QP_QKEY)
592                 qp->qkey = attr->qkey;
593
594         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
595                 qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
596
597         if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
598                 qp->s_max_rd_atomic = attr->max_rd_atomic;
599
600         spin_unlock_irq(&qp->s_lock);
601
602         if (lastwqe) {
603                 struct ib_event ev;
604
605                 ev.device = qp->ibqp.device;
606                 ev.element.qp = &qp->ibqp;
607                 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
608                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
609         }
610         ret = 0;
611         goto bail;
612
613 inval:
614         spin_unlock_irq(&qp->s_lock);
615         ret = -EINVAL;
616
617 bail:
618         return ret;
619 }
620
621 int ipath_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
622                    int attr_mask, struct ib_qp_init_attr *init_attr)
623 {
624         struct ipath_qp *qp = to_iqp(ibqp);
625
626         attr->qp_state = qp->state;
627         attr->cur_qp_state = attr->qp_state;
628         attr->path_mtu = qp->path_mtu;
629         attr->path_mig_state = 0;
630         attr->qkey = qp->qkey;
631         attr->rq_psn = qp->r_psn;
632         attr->sq_psn = qp->s_next_psn;
633         attr->dest_qp_num = qp->remote_qpn;
634         attr->qp_access_flags = qp->qp_access_flags;
635         attr->cap.max_send_wr = qp->s_size - 1;
636         attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
637         attr->cap.max_send_sge = qp->s_max_sge;
638         attr->cap.max_recv_sge = qp->r_rq.max_sge;
639         attr->cap.max_inline_data = 0;
640         attr->ah_attr = qp->remote_ah_attr;
641         memset(&attr->alt_ah_attr, 0, sizeof(attr->alt_ah_attr));
642         attr->pkey_index = qp->s_pkey_index;
643         attr->alt_pkey_index = 0;
644         attr->en_sqd_async_notify = 0;
645         attr->sq_draining = qp->s_draining;
646         attr->max_rd_atomic = qp->s_max_rd_atomic;
647         attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
648         attr->min_rnr_timer = qp->r_min_rnr_timer;
649         attr->port_num = 1;
650         attr->timeout = qp->timeout;
651         attr->retry_cnt = qp->s_retry_cnt;
652         attr->rnr_retry = qp->s_rnr_retry_cnt;
653         attr->alt_port_num = 0;
654         attr->alt_timeout = 0;
655
656         init_attr->event_handler = qp->ibqp.event_handler;
657         init_attr->qp_context = qp->ibqp.qp_context;
658         init_attr->send_cq = qp->ibqp.send_cq;
659         init_attr->recv_cq = qp->ibqp.recv_cq;
660         init_attr->srq = qp->ibqp.srq;
661         init_attr->cap = attr->cap;
662         if (qp->s_flags & IPATH_S_SIGNAL_REQ_WR)
663                 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
664         else
665                 init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
666         init_attr->qp_type = qp->ibqp.qp_type;
667         init_attr->port_num = 1;
668         return 0;
669 }
670
671 /**
672  * ipath_compute_aeth - compute the AETH (syndrome + MSN)
673  * @qp: the queue pair to compute the AETH for
674  *
675  * Returns the AETH.
676  */
677 __be32 ipath_compute_aeth(struct ipath_qp *qp)
678 {
679         u32 aeth = qp->r_msn & IPATH_MSN_MASK;
680
681         if (qp->ibqp.srq) {
682                 /*
683                  * Shared receive queues don't generate credits.
684                  * Set the credit field to the invalid value.
685                  */
686                 aeth |= IPATH_AETH_CREDIT_INVAL << IPATH_AETH_CREDIT_SHIFT;
687         } else {
688                 u32 min, max, x;
689                 u32 credits;
690                 struct ipath_rwq *wq = qp->r_rq.wq;
691                 u32 head;
692                 u32 tail;
693
694                 /* sanity check pointers before trusting them */
695                 head = wq->head;
696                 if (head >= qp->r_rq.size)
697                         head = 0;
698                 tail = wq->tail;
699                 if (tail >= qp->r_rq.size)
700                         tail = 0;
701                 /*
702                  * Compute the number of credits available (RWQEs).
703                  * XXX Not holding the r_rq.lock here so there is a small
704                  * chance that the pair of reads are not atomic.
705                  */
706                 credits = head - tail;
707                 if ((int)credits < 0)
708                         credits += qp->r_rq.size;
709                 /*
710                  * Binary search the credit table to find the code to
711                  * use.
712                  */
713                 min = 0;
714                 max = 31;
715                 for (;;) {
716                         x = (min + max) / 2;
717                         if (credit_table[x] == credits)
718                                 break;
719                         if (credit_table[x] > credits)
720                                 max = x;
721                         else if (min == x)
722                                 break;
723                         else
724                                 min = x;
725                 }
726                 aeth |= x << IPATH_AETH_CREDIT_SHIFT;
727         }
728         return cpu_to_be32(aeth);
729 }
730
731 /**
732  * ipath_create_qp - create a queue pair for a device
733  * @ibpd: the protection domain who's device we create the queue pair for
734  * @init_attr: the attributes of the queue pair
735  * @udata: unused by InfiniPath
736  *
737  * Returns the queue pair on success, otherwise returns an errno.
738  *
739  * Called by the ib_create_qp() core verbs function.
740  */
741 struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
742                               struct ib_qp_init_attr *init_attr,
743                               struct ib_udata *udata)
744 {
745         struct ipath_qp *qp;
746         int err;
747         struct ipath_swqe *swq = NULL;
748         struct ipath_ibdev *dev;
749         size_t sz;
750         size_t sg_list_sz;
751         struct ib_qp *ret;
752
753         if (init_attr->create_flags) {
754                 ret = ERR_PTR(-EINVAL);
755                 goto bail;
756         }
757
758         if (init_attr->cap.max_send_sge > ib_ipath_max_sges ||
759             init_attr->cap.max_send_wr > ib_ipath_max_qp_wrs) {
760                 ret = ERR_PTR(-EINVAL);
761                 goto bail;
762         }
763
764         /* Check receive queue parameters if no SRQ is specified. */
765         if (!init_attr->srq) {
766                 if (init_attr->cap.max_recv_sge > ib_ipath_max_sges ||
767                     init_attr->cap.max_recv_wr > ib_ipath_max_qp_wrs) {
768                         ret = ERR_PTR(-EINVAL);
769                         goto bail;
770                 }
771                 if (init_attr->cap.max_send_sge +
772                     init_attr->cap.max_send_wr +
773                     init_attr->cap.max_recv_sge +
774                     init_attr->cap.max_recv_wr == 0) {
775                         ret = ERR_PTR(-EINVAL);
776                         goto bail;
777                 }
778         }
779
780         switch (init_attr->qp_type) {
781         case IB_QPT_UC:
782         case IB_QPT_RC:
783         case IB_QPT_UD:
784         case IB_QPT_SMI:
785         case IB_QPT_GSI:
786                 sz = sizeof(struct ipath_sge) *
787                         init_attr->cap.max_send_sge +
788                         sizeof(struct ipath_swqe);
789                 swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
790                 if (swq == NULL) {
791                         ret = ERR_PTR(-ENOMEM);
792                         goto bail;
793                 }
794                 sz = sizeof(*qp);
795                 sg_list_sz = 0;
796                 if (init_attr->srq) {
797                         struct ipath_srq *srq = to_isrq(init_attr->srq);
798
799                         if (srq->rq.max_sge > 1)
800                                 sg_list_sz = sizeof(*qp->r_sg_list) *
801                                         (srq->rq.max_sge - 1);
802                 } else if (init_attr->cap.max_recv_sge > 1)
803                         sg_list_sz = sizeof(*qp->r_sg_list) *
804                                 (init_attr->cap.max_recv_sge - 1);
805                 qp = kmalloc(sz + sg_list_sz, GFP_KERNEL);
806                 if (!qp) {
807                         ret = ERR_PTR(-ENOMEM);
808                         goto bail_swq;
809                 }
810                 if (sg_list_sz && (init_attr->qp_type == IB_QPT_UD ||
811                     init_attr->qp_type == IB_QPT_SMI ||
812                     init_attr->qp_type == IB_QPT_GSI)) {
813                         qp->r_ud_sg_list = kmalloc(sg_list_sz, GFP_KERNEL);
814                         if (!qp->r_ud_sg_list) {
815                                 ret = ERR_PTR(-ENOMEM);
816                                 goto bail_qp;
817                         }
818                 } else
819                         qp->r_ud_sg_list = NULL;
820                 if (init_attr->srq) {
821                         sz = 0;
822                         qp->r_rq.size = 0;
823                         qp->r_rq.max_sge = 0;
824                         qp->r_rq.wq = NULL;
825                         init_attr->cap.max_recv_wr = 0;
826                         init_attr->cap.max_recv_sge = 0;
827                 } else {
828                         qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
829                         qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
830                         sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
831                                 sizeof(struct ipath_rwqe);
832                         qp->r_rq.wq = vmalloc_user(sizeof(struct ipath_rwq) +
833                                               qp->r_rq.size * sz);
834                         if (!qp->r_rq.wq) {
835                                 ret = ERR_PTR(-ENOMEM);
836                                 goto bail_sg_list;
837                         }
838                 }
839
840                 /*
841                  * ib_create_qp() will initialize qp->ibqp
842                  * except for qp->ibqp.qp_num.
843                  */
844                 spin_lock_init(&qp->s_lock);
845                 spin_lock_init(&qp->r_rq.lock);
846                 atomic_set(&qp->refcount, 0);
847                 init_waitqueue_head(&qp->wait);
848                 init_waitqueue_head(&qp->wait_dma);
849                 tasklet_init(&qp->s_task, ipath_do_send, (unsigned long)qp);
850                 INIT_LIST_HEAD(&qp->piowait);
851                 INIT_LIST_HEAD(&qp->timerwait);
852                 qp->state = IB_QPS_RESET;
853                 qp->s_wq = swq;
854                 qp->s_size = init_attr->cap.max_send_wr + 1;
855                 qp->s_max_sge = init_attr->cap.max_send_sge;
856                 if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
857                         qp->s_flags = IPATH_S_SIGNAL_REQ_WR;
858                 else
859                         qp->s_flags = 0;
860                 dev = to_idev(ibpd->device);
861                 err = ipath_alloc_qpn(&dev->qp_table, qp,
862                                       init_attr->qp_type);
863                 if (err) {
864                         ret = ERR_PTR(err);
865                         vfree(qp->r_rq.wq);
866                         goto bail_sg_list;
867                 }
868                 qp->ip = NULL;
869                 qp->s_tx = NULL;
870                 ipath_reset_qp(qp, init_attr->qp_type);
871                 break;
872
873         default:
874                 /* Don't support raw QPs */
875                 ret = ERR_PTR(-ENOSYS);
876                 goto bail;
877         }
878
879         init_attr->cap.max_inline_data = 0;
880
881         /*
882          * Return the address of the RWQ as the offset to mmap.
883          * See ipath_mmap() for details.
884          */
885         if (udata && udata->outlen >= sizeof(__u64)) {
886                 if (!qp->r_rq.wq) {
887                         __u64 offset = 0;
888
889                         err = ib_copy_to_udata(udata, &offset,
890                                                sizeof(offset));
891                         if (err) {
892                                 ret = ERR_PTR(err);
893                                 goto bail_ip;
894                         }
895                 } else {
896                         u32 s = sizeof(struct ipath_rwq) +
897                                 qp->r_rq.size * sz;
898
899                         qp->ip =
900                             ipath_create_mmap_info(dev, s,
901                                                    ibpd->uobject->context,
902                                                    qp->r_rq.wq);
903                         if (!qp->ip) {
904                                 ret = ERR_PTR(-ENOMEM);
905                                 goto bail_ip;
906                         }
907
908                         err = ib_copy_to_udata(udata, &(qp->ip->offset),
909                                                sizeof(qp->ip->offset));
910                         if (err) {
911                                 ret = ERR_PTR(err);
912                                 goto bail_ip;
913                         }
914                 }
915         }
916
917         spin_lock(&dev->n_qps_lock);
918         if (dev->n_qps_allocated == ib_ipath_max_qps) {
919                 spin_unlock(&dev->n_qps_lock);
920                 ret = ERR_PTR(-ENOMEM);
921                 goto bail_ip;
922         }
923
924         dev->n_qps_allocated++;
925         spin_unlock(&dev->n_qps_lock);
926
927         if (qp->ip) {
928                 spin_lock_irq(&dev->pending_lock);
929                 list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
930                 spin_unlock_irq(&dev->pending_lock);
931         }
932
933         ret = &qp->ibqp;
934         goto bail;
935
936 bail_ip:
937         if (qp->ip)
938                 kref_put(&qp->ip->ref, ipath_release_mmap_info);
939         else
940                 vfree(qp->r_rq.wq);
941         ipath_free_qp(&dev->qp_table, qp);
942         free_qpn(&dev->qp_table, qp->ibqp.qp_num);
943 bail_sg_list:
944         kfree(qp->r_ud_sg_list);
945 bail_qp:
946         kfree(qp);
947 bail_swq:
948         vfree(swq);
949 bail:
950         return ret;
951 }
952
953 /**
954  * ipath_destroy_qp - destroy a queue pair
955  * @ibqp: the queue pair to destroy
956  *
957  * Returns 0 on success.
958  *
959  * Note that this can be called while the QP is actively sending or
960  * receiving!
961  */
962 int ipath_destroy_qp(struct ib_qp *ibqp)
963 {
964         struct ipath_qp *qp = to_iqp(ibqp);
965         struct ipath_ibdev *dev = to_idev(ibqp->device);
966
967         /* Make sure HW and driver activity is stopped. */
968         spin_lock_irq(&qp->s_lock);
969         if (qp->state != IB_QPS_RESET) {
970                 qp->state = IB_QPS_RESET;
971                 spin_lock(&dev->pending_lock);
972                 if (!list_empty(&qp->timerwait))
973                         list_del_init(&qp->timerwait);
974                 if (!list_empty(&qp->piowait))
975                         list_del_init(&qp->piowait);
976                 spin_unlock(&dev->pending_lock);
977                 qp->s_flags &= ~IPATH_S_ANY_WAIT;
978                 spin_unlock_irq(&qp->s_lock);
979                 /* Stop the sending tasklet */
980                 tasklet_kill(&qp->s_task);
981                 wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
982         } else
983                 spin_unlock_irq(&qp->s_lock);
984
985         ipath_free_qp(&dev->qp_table, qp);
986
987         if (qp->s_tx) {
988                 atomic_dec(&qp->refcount);
989                 if (qp->s_tx->txreq.flags & IPATH_SDMA_TXREQ_F_FREEBUF)
990                         kfree(qp->s_tx->txreq.map_addr);
991                 spin_lock_irq(&dev->pending_lock);
992                 list_add(&qp->s_tx->txreq.list, &dev->txreq_free);
993                 spin_unlock_irq(&dev->pending_lock);
994                 qp->s_tx = NULL;
995         }
996
997         wait_event(qp->wait, !atomic_read(&qp->refcount));
998
999         /* all user's cleaned up, mark it available */
1000         free_qpn(&dev->qp_table, qp->ibqp.qp_num);
1001         spin_lock(&dev->n_qps_lock);
1002         dev->n_qps_allocated--;
1003         spin_unlock(&dev->n_qps_lock);
1004
1005         if (qp->ip)
1006                 kref_put(&qp->ip->ref, ipath_release_mmap_info);
1007         else
1008                 vfree(qp->r_rq.wq);
1009         kfree(qp->r_ud_sg_list);
1010         vfree(qp->s_wq);
1011         kfree(qp);
1012         return 0;
1013 }
1014
1015 /**
1016  * ipath_init_qp_table - initialize the QP table for a device
1017  * @idev: the device who's QP table we're initializing
1018  * @size: the size of the QP table
1019  *
1020  * Returns 0 on success, otherwise returns an errno.
1021  */
1022 int ipath_init_qp_table(struct ipath_ibdev *idev, int size)
1023 {
1024         int i;
1025         int ret;
1026
1027         idev->qp_table.last = 1;        /* QPN 0 and 1 are special. */
1028         idev->qp_table.max = size;
1029         idev->qp_table.nmaps = 1;
1030         idev->qp_table.table = kzalloc(size * sizeof(*idev->qp_table.table),
1031                                        GFP_KERNEL);
1032         if (idev->qp_table.table == NULL) {
1033                 ret = -ENOMEM;
1034                 goto bail;
1035         }
1036
1037         for (i = 0; i < ARRAY_SIZE(idev->qp_table.map); i++) {
1038                 atomic_set(&idev->qp_table.map[i].n_free, BITS_PER_PAGE);
1039                 idev->qp_table.map[i].page = NULL;
1040         }
1041
1042         ret = 0;
1043
1044 bail:
1045         return ret;
1046 }
1047
1048 /**
1049  * ipath_get_credit - flush the send work queue of a QP
1050  * @qp: the qp who's send work queue to flush
1051  * @aeth: the Acknowledge Extended Transport Header
1052  *
1053  * The QP s_lock should be held.
1054  */
1055 void ipath_get_credit(struct ipath_qp *qp, u32 aeth)
1056 {
1057         u32 credit = (aeth >> IPATH_AETH_CREDIT_SHIFT) & IPATH_AETH_CREDIT_MASK;
1058
1059         /*
1060          * If the credit is invalid, we can send
1061          * as many packets as we like.  Otherwise, we have to
1062          * honor the credit field.
1063          */
1064         if (credit == IPATH_AETH_CREDIT_INVAL)
1065                 qp->s_lsn = (u32) -1;
1066         else if (qp->s_lsn != (u32) -1) {
1067                 /* Compute new LSN (i.e., MSN + credit) */
1068                 credit = (aeth + credit_table[credit]) & IPATH_MSN_MASK;
1069                 if (ipath_cmp24(credit, qp->s_lsn) > 0)
1070                         qp->s_lsn = credit;
1071         }
1072
1073         /* Restart sending if it was blocked due to lack of credits. */
1074         if ((qp->s_flags & IPATH_S_WAIT_SSN_CREDIT) &&
1075             qp->s_cur != qp->s_head &&
1076             (qp->s_lsn == (u32) -1 ||
1077              ipath_cmp24(get_swqe_ptr(qp, qp->s_cur)->ssn,
1078                          qp->s_lsn + 1) <= 0))
1079                 ipath_schedule_send(qp);
1080 }