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 
get_map_page(struct ipath_qp_table * qpt,struct qpn_map * map)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 
alloc_qpn(struct ipath_qp_table * qpt,enum ib_qp_type type)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 
free_qpn(struct ipath_qp_table * qpt,u32 qpn)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  */
ipath_alloc_qpn(struct ipath_qp_table * qpt,struct ipath_qp * qp,enum ib_qp_type type)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  */
ipath_free_qp(struct ipath_qp_table * qpt,struct ipath_qp * qp)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  */
ipath_free_all_qps(struct ipath_qp_table * qpt)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  */
ipath_lookup_qpn(struct ipath_qp_table * qpt,u32 qpn)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  */
ipath_reset_qp(struct ipath_qp * qp,enum ib_qp_type type)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 
ipath_error_qp(struct ipath_qp * qp,enum ib_wc_status err)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  */
ipath_modify_qp(struct ib_qp * ibqp,struct ib_qp_attr * attr,int attr_mask,struct ib_udata * udata)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 
ipath_query_qp(struct ib_qp * ibqp,struct ib_qp_attr * attr,int attr_mask,struct ib_qp_init_attr * init_attr)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  */
ipath_compute_aeth(struct ipath_qp * qp)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  */
ipath_create_qp(struct ib_pd * ibpd,struct ib_qp_init_attr * init_attr,struct ib_udata * udata)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  */
ipath_destroy_qp(struct ib_qp * ibqp)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  */
ipath_init_qp_table(struct ipath_ibdev * idev,int size)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  */
ipath_get_credit(struct ipath_qp * qp,u32 aeth)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 }
1081