ipath_qp.c revision 9bc57e2d19db4da81c1150120658cc3658a99ed4
1/*
2 * Copyright (c) 2006 QLogic, Inc. 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_common.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#define TRANS_INVALID	0
48#define TRANS_ANY2RST	1
49#define TRANS_RST2INIT	2
50#define TRANS_INIT2INIT	3
51#define TRANS_INIT2RTR	4
52#define TRANS_RTR2RTS	5
53#define TRANS_RTS2RTS	6
54#define TRANS_SQERR2RTS	7
55#define TRANS_ANY2ERR	8
56#define TRANS_RTS2SQD	9  /* XXX Wait for expected ACKs & signal event */
57#define TRANS_SQD2SQD	10 /* error if not drained & parameter change */
58#define TRANS_SQD2RTS	11 /* error if not drained */
59
60/*
61 * Convert the AETH credit code into the number of credits.
62 */
63static u32 credit_table[31] = {
64	0,			/* 0 */
65	1,			/* 1 */
66	2,			/* 2 */
67	3,			/* 3 */
68	4,			/* 4 */
69	6,			/* 5 */
70	8,			/* 6 */
71	12,			/* 7 */
72	16,			/* 8 */
73	24,			/* 9 */
74	32,			/* A */
75	48,			/* B */
76	64,			/* C */
77	96,			/* D */
78	128,			/* E */
79	192,			/* F */
80	256,			/* 10 */
81	384,			/* 11 */
82	512,			/* 12 */
83	768,			/* 13 */
84	1024,			/* 14 */
85	1536,			/* 15 */
86	2048,			/* 16 */
87	3072,			/* 17 */
88	4096,			/* 18 */
89	6144,			/* 19 */
90	8192,			/* 1A */
91	12288,			/* 1B */
92	16384,			/* 1C */
93	24576,			/* 1D */
94	32768			/* 1E */
95};
96
97static u32 alloc_qpn(struct ipath_qp_table *qpt)
98{
99	u32 i, offset, max_scan, qpn;
100	struct qpn_map *map;
101	u32 ret;
102
103	qpn = qpt->last + 1;
104	if (qpn >= QPN_MAX)
105		qpn = 2;
106	offset = qpn & BITS_PER_PAGE_MASK;
107	map = &qpt->map[qpn / BITS_PER_PAGE];
108	max_scan = qpt->nmaps - !offset;
109	for (i = 0;;) {
110		if (unlikely(!map->page)) {
111			unsigned long page = get_zeroed_page(GFP_KERNEL);
112			unsigned long flags;
113
114			/*
115			 * Free the page if someone raced with us
116			 * installing it:
117			 */
118			spin_lock_irqsave(&qpt->lock, flags);
119			if (map->page)
120				free_page(page);
121			else
122				map->page = (void *)page;
123			spin_unlock_irqrestore(&qpt->lock, flags);
124			if (unlikely(!map->page))
125				break;
126		}
127		if (likely(atomic_read(&map->n_free))) {
128			do {
129				if (!test_and_set_bit(offset, map->page)) {
130					atomic_dec(&map->n_free);
131					qpt->last = qpn;
132					ret = qpn;
133					goto bail;
134				}
135				offset = find_next_offset(map, offset);
136				qpn = mk_qpn(qpt, map, offset);
137				/*
138				 * This test differs from alloc_pidmap().
139				 * If find_next_offset() does find a zero
140				 * bit, we don't need to check for QPN
141				 * wrapping around past our starting QPN.
142				 * We just need to be sure we don't loop
143				 * forever.
144				 */
145			} while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
146		}
147		/*
148		 * In order to keep the number of pages allocated to a
149		 * minimum, we scan the all existing pages before increasing
150		 * the size of the bitmap table.
151		 */
152		if (++i > max_scan) {
153			if (qpt->nmaps == QPNMAP_ENTRIES)
154				break;
155			map = &qpt->map[qpt->nmaps++];
156			offset = 0;
157		} else if (map < &qpt->map[qpt->nmaps]) {
158			++map;
159			offset = 0;
160		} else {
161			map = &qpt->map[0];
162			offset = 2;
163		}
164		qpn = mk_qpn(qpt, map, offset);
165	}
166
167	ret = 0;
168
169bail:
170	return ret;
171}
172
173static void free_qpn(struct ipath_qp_table *qpt, u32 qpn)
174{
175	struct qpn_map *map;
176
177	map = qpt->map + qpn / BITS_PER_PAGE;
178	if (map->page)
179		clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
180	atomic_inc(&map->n_free);
181}
182
183/**
184 * ipath_alloc_qpn - allocate a QP number
185 * @qpt: the QP table
186 * @qp: the QP
187 * @type: the QP type (IB_QPT_SMI and IB_QPT_GSI are special)
188 *
189 * Allocate the next available QPN and put the QP into the hash table.
190 * The hash table holds a reference to the QP.
191 */
192static int ipath_alloc_qpn(struct ipath_qp_table *qpt, struct ipath_qp *qp,
193			   enum ib_qp_type type)
194{
195	unsigned long flags;
196	u32 qpn;
197	int ret;
198
199	if (type == IB_QPT_SMI)
200		qpn = 0;
201	else if (type == IB_QPT_GSI)
202		qpn = 1;
203	else {
204		/* Allocate the next available QPN */
205		qpn = alloc_qpn(qpt);
206		if (qpn == 0) {
207			ret = -ENOMEM;
208			goto bail;
209		}
210	}
211	qp->ibqp.qp_num = qpn;
212
213	/* Add the QP to the hash table. */
214	spin_lock_irqsave(&qpt->lock, flags);
215
216	qpn %= qpt->max;
217	qp->next = qpt->table[qpn];
218	qpt->table[qpn] = qp;
219	atomic_inc(&qp->refcount);
220
221	spin_unlock_irqrestore(&qpt->lock, flags);
222	ret = 0;
223
224bail:
225	return ret;
226}
227
228/**
229 * ipath_free_qp - remove a QP from the QP table
230 * @qpt: the QP table
231 * @qp: the QP to remove
232 *
233 * Remove the QP from the table so it can't be found asynchronously by
234 * the receive interrupt routine.
235 */
236static void ipath_free_qp(struct ipath_qp_table *qpt, struct ipath_qp *qp)
237{
238	struct ipath_qp *q, **qpp;
239	unsigned long flags;
240	int fnd = 0;
241
242	spin_lock_irqsave(&qpt->lock, flags);
243
244	/* Remove QP from the hash table. */
245	qpp = &qpt->table[qp->ibqp.qp_num % qpt->max];
246	for (; (q = *qpp) != NULL; qpp = &q->next) {
247		if (q == qp) {
248			*qpp = qp->next;
249			qp->next = NULL;
250			atomic_dec(&qp->refcount);
251			fnd = 1;
252			break;
253		}
254	}
255
256	spin_unlock_irqrestore(&qpt->lock, flags);
257
258	if (!fnd)
259		return;
260
261	/* If QPN is not reserved, mark QPN free in the bitmap. */
262	if (qp->ibqp.qp_num > 1)
263		free_qpn(qpt, qp->ibqp.qp_num);
264
265	wait_event(qp->wait, !atomic_read(&qp->refcount));
266}
267
268/**
269 * ipath_free_all_qps - remove all QPs from the table
270 * @qpt: the QP table to empty
271 */
272void ipath_free_all_qps(struct ipath_qp_table *qpt)
273{
274	unsigned long flags;
275	struct ipath_qp *qp, *nqp;
276	u32 n;
277
278	for (n = 0; n < qpt->max; n++) {
279		spin_lock_irqsave(&qpt->lock, flags);
280		qp = qpt->table[n];
281		qpt->table[n] = NULL;
282		spin_unlock_irqrestore(&qpt->lock, flags);
283
284		while (qp) {
285			nqp = qp->next;
286			if (qp->ibqp.qp_num > 1)
287				free_qpn(qpt, qp->ibqp.qp_num);
288			if (!atomic_dec_and_test(&qp->refcount) ||
289			    !ipath_destroy_qp(&qp->ibqp))
290				_VERBS_INFO("QP memory leak!\n");
291			qp = nqp;
292		}
293	}
294
295	for (n = 0; n < ARRAY_SIZE(qpt->map); n++) {
296		if (qpt->map[n].page)
297			free_page((unsigned long)qpt->map[n].page);
298	}
299}
300
301/**
302 * ipath_lookup_qpn - return the QP with the given QPN
303 * @qpt: the QP table
304 * @qpn: the QP number to look up
305 *
306 * The caller is responsible for decrementing the QP reference count
307 * when done.
308 */
309struct ipath_qp *ipath_lookup_qpn(struct ipath_qp_table *qpt, u32 qpn)
310{
311	unsigned long flags;
312	struct ipath_qp *qp;
313
314	spin_lock_irqsave(&qpt->lock, flags);
315
316	for (qp = qpt->table[qpn % qpt->max]; qp; qp = qp->next) {
317		if (qp->ibqp.qp_num == qpn) {
318			atomic_inc(&qp->refcount);
319			break;
320		}
321	}
322
323	spin_unlock_irqrestore(&qpt->lock, flags);
324	return qp;
325}
326
327/**
328 * ipath_reset_qp - initialize the QP state to the reset state
329 * @qp: the QP to reset
330 */
331static void ipath_reset_qp(struct ipath_qp *qp)
332{
333	qp->remote_qpn = 0;
334	qp->qkey = 0;
335	qp->qp_access_flags = 0;
336	clear_bit(IPATH_S_BUSY, &qp->s_flags);
337	qp->s_hdrwords = 0;
338	qp->s_psn = 0;
339	qp->r_psn = 0;
340	qp->r_msn = 0;
341	if (qp->ibqp.qp_type == IB_QPT_RC) {
342		qp->s_state = IB_OPCODE_RC_SEND_LAST;
343		qp->r_state = IB_OPCODE_RC_SEND_LAST;
344	} else {
345		qp->s_state = IB_OPCODE_UC_SEND_LAST;
346		qp->r_state = IB_OPCODE_UC_SEND_LAST;
347	}
348	qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
349	qp->r_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
350	qp->r_nak_state = 0;
351	qp->s_rnr_timeout = 0;
352	qp->s_head = 0;
353	qp->s_tail = 0;
354	qp->s_cur = 0;
355	qp->s_last = 0;
356	qp->s_ssn = 1;
357	qp->s_lsn = 0;
358	qp->r_rq.head = 0;
359	qp->r_rq.tail = 0;
360	qp->r_reuse_sge = 0;
361}
362
363/**
364 * ipath_error_qp - put a QP into an error state
365 * @qp: the QP to put into an error state
366 *
367 * Flushes both send and receive work queues.
368 * QP s_lock should be held and interrupts disabled.
369 */
370
371void ipath_error_qp(struct ipath_qp *qp)
372{
373	struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
374	struct ib_wc wc;
375
376	_VERBS_INFO("QP%d/%d in error state\n",
377		    qp->ibqp.qp_num, qp->remote_qpn);
378
379	spin_lock(&dev->pending_lock);
380	/* XXX What if its already removed by the timeout code? */
381	if (!list_empty(&qp->timerwait))
382		list_del_init(&qp->timerwait);
383	if (!list_empty(&qp->piowait))
384		list_del_init(&qp->piowait);
385	spin_unlock(&dev->pending_lock);
386
387	wc.status = IB_WC_WR_FLUSH_ERR;
388	wc.vendor_err = 0;
389	wc.byte_len = 0;
390	wc.imm_data = 0;
391	wc.qp_num = qp->ibqp.qp_num;
392	wc.src_qp = 0;
393	wc.wc_flags = 0;
394	wc.pkey_index = 0;
395	wc.slid = 0;
396	wc.sl = 0;
397	wc.dlid_path_bits = 0;
398	wc.port_num = 0;
399
400	while (qp->s_last != qp->s_head) {
401		struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
402
403		wc.wr_id = wqe->wr.wr_id;
404		wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
405		if (++qp->s_last >= qp->s_size)
406			qp->s_last = 0;
407		ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 1);
408	}
409	qp->s_cur = qp->s_tail = qp->s_head;
410	qp->s_hdrwords = 0;
411	qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
412
413	wc.opcode = IB_WC_RECV;
414	spin_lock(&qp->r_rq.lock);
415	while (qp->r_rq.tail != qp->r_rq.head) {
416		wc.wr_id = get_rwqe_ptr(&qp->r_rq, qp->r_rq.tail)->wr_id;
417		if (++qp->r_rq.tail >= qp->r_rq.size)
418			qp->r_rq.tail = 0;
419		ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
420	}
421	spin_unlock(&qp->r_rq.lock);
422}
423
424/**
425 * ipath_modify_qp - modify the attributes of a queue pair
426 * @ibqp: the queue pair who's attributes we're modifying
427 * @attr: the new attributes
428 * @attr_mask: the mask of attributes to modify
429 * @udata: user data for ipathverbs.so
430 *
431 * Returns 0 on success, otherwise returns an errno.
432 */
433int ipath_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
434		    int attr_mask, struct ib_udata *udata)
435{
436	struct ipath_ibdev *dev = to_idev(ibqp->device);
437	struct ipath_qp *qp = to_iqp(ibqp);
438	enum ib_qp_state cur_state, new_state;
439	unsigned long flags;
440	int ret;
441
442	spin_lock_irqsave(&qp->s_lock, flags);
443
444	cur_state = attr_mask & IB_QP_CUR_STATE ?
445		attr->cur_qp_state : qp->state;
446	new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
447
448	if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
449				attr_mask))
450		goto inval;
451
452	if (attr_mask & IB_QP_AV)
453		if (attr->ah_attr.dlid == 0 ||
454		    attr->ah_attr.dlid >= IPATH_MULTICAST_LID_BASE)
455			goto inval;
456
457	if (attr_mask & IB_QP_PKEY_INDEX)
458		if (attr->pkey_index >= ipath_layer_get_npkeys(dev->dd))
459			goto inval;
460
461	if (attr_mask & IB_QP_MIN_RNR_TIMER)
462		if (attr->min_rnr_timer > 31)
463			goto inval;
464
465	switch (new_state) {
466	case IB_QPS_RESET:
467		ipath_reset_qp(qp);
468		break;
469
470	case IB_QPS_ERR:
471		ipath_error_qp(qp);
472		break;
473
474	default:
475		break;
476
477	}
478
479	if (attr_mask & IB_QP_PKEY_INDEX)
480		qp->s_pkey_index = attr->pkey_index;
481
482	if (attr_mask & IB_QP_DEST_QPN)
483		qp->remote_qpn = attr->dest_qp_num;
484
485	if (attr_mask & IB_QP_SQ_PSN) {
486		qp->s_next_psn = attr->sq_psn;
487		qp->s_last_psn = qp->s_next_psn - 1;
488	}
489
490	if (attr_mask & IB_QP_RQ_PSN)
491		qp->r_psn = attr->rq_psn;
492
493	if (attr_mask & IB_QP_ACCESS_FLAGS)
494		qp->qp_access_flags = attr->qp_access_flags;
495
496	if (attr_mask & IB_QP_AV)
497		qp->remote_ah_attr = attr->ah_attr;
498
499	if (attr_mask & IB_QP_PATH_MTU)
500		qp->path_mtu = attr->path_mtu;
501
502	if (attr_mask & IB_QP_RETRY_CNT)
503		qp->s_retry = qp->s_retry_cnt = attr->retry_cnt;
504
505	if (attr_mask & IB_QP_RNR_RETRY) {
506		qp->s_rnr_retry = attr->rnr_retry;
507		if (qp->s_rnr_retry > 7)
508			qp->s_rnr_retry = 7;
509		qp->s_rnr_retry_cnt = qp->s_rnr_retry;
510	}
511
512	if (attr_mask & IB_QP_MIN_RNR_TIMER)
513		qp->r_min_rnr_timer = attr->min_rnr_timer;
514
515	if (attr_mask & IB_QP_QKEY)
516		qp->qkey = attr->qkey;
517
518	qp->state = new_state;
519	spin_unlock_irqrestore(&qp->s_lock, flags);
520
521	ret = 0;
522	goto bail;
523
524inval:
525	spin_unlock_irqrestore(&qp->s_lock, flags);
526	ret = -EINVAL;
527
528bail:
529	return ret;
530}
531
532int ipath_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
533		   int attr_mask, struct ib_qp_init_attr *init_attr)
534{
535	struct ipath_qp *qp = to_iqp(ibqp);
536
537	attr->qp_state = qp->state;
538	attr->cur_qp_state = attr->qp_state;
539	attr->path_mtu = qp->path_mtu;
540	attr->path_mig_state = 0;
541	attr->qkey = qp->qkey;
542	attr->rq_psn = qp->r_psn;
543	attr->sq_psn = qp->s_next_psn;
544	attr->dest_qp_num = qp->remote_qpn;
545	attr->qp_access_flags = qp->qp_access_flags;
546	attr->cap.max_send_wr = qp->s_size - 1;
547	attr->cap.max_recv_wr = qp->r_rq.size - 1;
548	attr->cap.max_send_sge = qp->s_max_sge;
549	attr->cap.max_recv_sge = qp->r_rq.max_sge;
550	attr->cap.max_inline_data = 0;
551	attr->ah_attr = qp->remote_ah_attr;
552	memset(&attr->alt_ah_attr, 0, sizeof(attr->alt_ah_attr));
553	attr->pkey_index = qp->s_pkey_index;
554	attr->alt_pkey_index = 0;
555	attr->en_sqd_async_notify = 0;
556	attr->sq_draining = 0;
557	attr->max_rd_atomic = 1;
558	attr->max_dest_rd_atomic = 1;
559	attr->min_rnr_timer = qp->r_min_rnr_timer;
560	attr->port_num = 1;
561	attr->timeout = 0;
562	attr->retry_cnt = qp->s_retry_cnt;
563	attr->rnr_retry = qp->s_rnr_retry;
564	attr->alt_port_num = 0;
565	attr->alt_timeout = 0;
566
567	init_attr->event_handler = qp->ibqp.event_handler;
568	init_attr->qp_context = qp->ibqp.qp_context;
569	init_attr->send_cq = qp->ibqp.send_cq;
570	init_attr->recv_cq = qp->ibqp.recv_cq;
571	init_attr->srq = qp->ibqp.srq;
572	init_attr->cap = attr->cap;
573	init_attr->sq_sig_type =
574		(qp->s_flags & (1 << IPATH_S_SIGNAL_REQ_WR))
575		? IB_SIGNAL_REQ_WR : 0;
576	init_attr->qp_type = qp->ibqp.qp_type;
577	init_attr->port_num = 1;
578	return 0;
579}
580
581/**
582 * ipath_compute_aeth - compute the AETH (syndrome + MSN)
583 * @qp: the queue pair to compute the AETH for
584 *
585 * Returns the AETH.
586 */
587__be32 ipath_compute_aeth(struct ipath_qp *qp)
588{
589	u32 aeth = qp->r_msn & IPATH_MSN_MASK;
590
591	if (qp->ibqp.srq) {
592		/*
593		 * Shared receive queues don't generate credits.
594		 * Set the credit field to the invalid value.
595		 */
596		aeth |= IPATH_AETH_CREDIT_INVAL << IPATH_AETH_CREDIT_SHIFT;
597	} else {
598		u32 min, max, x;
599		u32 credits;
600
601		/*
602		 * Compute the number of credits available (RWQEs).
603		 * XXX Not holding the r_rq.lock here so there is a small
604		 * chance that the pair of reads are not atomic.
605		 */
606		credits = qp->r_rq.head - qp->r_rq.tail;
607		if ((int)credits < 0)
608			credits += qp->r_rq.size;
609		/*
610		 * Binary search the credit table to find the code to
611		 * use.
612		 */
613		min = 0;
614		max = 31;
615		for (;;) {
616			x = (min + max) / 2;
617			if (credit_table[x] == credits)
618				break;
619			if (credit_table[x] > credits)
620				max = x;
621			else if (min == x)
622				break;
623			else
624				min = x;
625		}
626		aeth |= x << IPATH_AETH_CREDIT_SHIFT;
627	}
628	return cpu_to_be32(aeth);
629}
630
631/**
632 * ipath_create_qp - create a queue pair for a device
633 * @ibpd: the protection domain who's device we create the queue pair for
634 * @init_attr: the attributes of the queue pair
635 * @udata: unused by InfiniPath
636 *
637 * Returns the queue pair on success, otherwise returns an errno.
638 *
639 * Called by the ib_create_qp() core verbs function.
640 */
641struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
642			      struct ib_qp_init_attr *init_attr,
643			      struct ib_udata *udata)
644{
645	struct ipath_qp *qp;
646	int err;
647	struct ipath_swqe *swq = NULL;
648	struct ipath_ibdev *dev;
649	size_t sz;
650	struct ib_qp *ret;
651
652	if (init_attr->cap.max_send_sge > ib_ipath_max_sges ||
653	    init_attr->cap.max_recv_sge > ib_ipath_max_sges ||
654	    init_attr->cap.max_send_wr > ib_ipath_max_qp_wrs ||
655	    init_attr->cap.max_recv_wr > ib_ipath_max_qp_wrs) {
656		ret = ERR_PTR(-ENOMEM);
657		goto bail;
658	}
659
660	if (init_attr->cap.max_send_sge +
661	    init_attr->cap.max_recv_sge +
662	    init_attr->cap.max_send_wr +
663	    init_attr->cap.max_recv_wr == 0) {
664		ret = ERR_PTR(-EINVAL);
665		goto bail;
666	}
667
668	switch (init_attr->qp_type) {
669	case IB_QPT_UC:
670	case IB_QPT_RC:
671		sz = sizeof(struct ipath_sge) *
672			init_attr->cap.max_send_sge +
673			sizeof(struct ipath_swqe);
674		swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
675		if (swq == NULL) {
676			ret = ERR_PTR(-ENOMEM);
677			goto bail;
678		}
679		/* FALLTHROUGH */
680	case IB_QPT_UD:
681	case IB_QPT_SMI:
682	case IB_QPT_GSI:
683		qp = kmalloc(sizeof(*qp), GFP_KERNEL);
684		if (!qp) {
685			vfree(swq);
686			ret = ERR_PTR(-ENOMEM);
687			goto bail;
688		}
689		if (init_attr->srq) {
690			qp->r_rq.size = 0;
691			qp->r_rq.max_sge = 0;
692			qp->r_rq.wq = NULL;
693		} else {
694			qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
695			qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
696			sz = (sizeof(struct ipath_sge) * qp->r_rq.max_sge) +
697				sizeof(struct ipath_rwqe);
698			qp->r_rq.wq = vmalloc(qp->r_rq.size * sz);
699			if (!qp->r_rq.wq) {
700				kfree(qp);
701				vfree(swq);
702				ret = ERR_PTR(-ENOMEM);
703				goto bail;
704			}
705		}
706
707		/*
708		 * ib_create_qp() will initialize qp->ibqp
709		 * except for qp->ibqp.qp_num.
710		 */
711		spin_lock_init(&qp->s_lock);
712		spin_lock_init(&qp->r_rq.lock);
713		atomic_set(&qp->refcount, 0);
714		init_waitqueue_head(&qp->wait);
715		tasklet_init(&qp->s_task, ipath_do_ruc_send,
716			     (unsigned long)qp);
717		INIT_LIST_HEAD(&qp->piowait);
718		INIT_LIST_HEAD(&qp->timerwait);
719		qp->state = IB_QPS_RESET;
720		qp->s_wq = swq;
721		qp->s_size = init_attr->cap.max_send_wr + 1;
722		qp->s_max_sge = init_attr->cap.max_send_sge;
723		qp->s_flags = init_attr->sq_sig_type == IB_SIGNAL_REQ_WR ?
724			1 << IPATH_S_SIGNAL_REQ_WR : 0;
725		dev = to_idev(ibpd->device);
726		err = ipath_alloc_qpn(&dev->qp_table, qp,
727				      init_attr->qp_type);
728		if (err) {
729			vfree(swq);
730			vfree(qp->r_rq.wq);
731			kfree(qp);
732			ret = ERR_PTR(err);
733			goto bail;
734		}
735		ipath_reset_qp(qp);
736
737		/* Tell the core driver that the kernel SMA is present. */
738		if (init_attr->qp_type == IB_QPT_SMI)
739			ipath_layer_set_verbs_flags(dev->dd,
740						    IPATH_VERBS_KERNEL_SMA);
741		break;
742
743	default:
744		/* Don't support raw QPs */
745		ret = ERR_PTR(-ENOSYS);
746		goto bail;
747	}
748
749	init_attr->cap.max_inline_data = 0;
750
751	ret = &qp->ibqp;
752
753bail:
754	return ret;
755}
756
757/**
758 * ipath_destroy_qp - destroy a queue pair
759 * @ibqp: the queue pair to destroy
760 *
761 * Returns 0 on success.
762 *
763 * Note that this can be called while the QP is actively sending or
764 * receiving!
765 */
766int ipath_destroy_qp(struct ib_qp *ibqp)
767{
768	struct ipath_qp *qp = to_iqp(ibqp);
769	struct ipath_ibdev *dev = to_idev(ibqp->device);
770	unsigned long flags;
771
772	/* Tell the core driver that the kernel SMA is gone. */
773	if (qp->ibqp.qp_type == IB_QPT_SMI)
774		ipath_layer_set_verbs_flags(dev->dd, 0);
775
776	spin_lock_irqsave(&qp->r_rq.lock, flags);
777	spin_lock(&qp->s_lock);
778	qp->state = IB_QPS_ERR;
779	spin_unlock(&qp->s_lock);
780	spin_unlock_irqrestore(&qp->r_rq.lock, flags);
781
782	/* Stop the sending tasklet. */
783	tasklet_kill(&qp->s_task);
784
785	/* Make sure the QP isn't on the timeout list. */
786	spin_lock_irqsave(&dev->pending_lock, flags);
787	if (!list_empty(&qp->timerwait))
788		list_del_init(&qp->timerwait);
789	if (!list_empty(&qp->piowait))
790		list_del_init(&qp->piowait);
791	spin_unlock_irqrestore(&dev->pending_lock, flags);
792
793	/*
794	 * Make sure that the QP is not in the QPN table so receive
795	 * interrupts will discard packets for this QP.  XXX Also remove QP
796	 * from multicast table.
797	 */
798	if (atomic_read(&qp->refcount) != 0)
799		ipath_free_qp(&dev->qp_table, qp);
800
801	vfree(qp->s_wq);
802	vfree(qp->r_rq.wq);
803	kfree(qp);
804	return 0;
805}
806
807/**
808 * ipath_init_qp_table - initialize the QP table for a device
809 * @idev: the device who's QP table we're initializing
810 * @size: the size of the QP table
811 *
812 * Returns 0 on success, otherwise returns an errno.
813 */
814int ipath_init_qp_table(struct ipath_ibdev *idev, int size)
815{
816	int i;
817	int ret;
818
819	idev->qp_table.last = 1;	/* QPN 0 and 1 are special. */
820	idev->qp_table.max = size;
821	idev->qp_table.nmaps = 1;
822	idev->qp_table.table = kzalloc(size * sizeof(*idev->qp_table.table),
823				       GFP_KERNEL);
824	if (idev->qp_table.table == NULL) {
825		ret = -ENOMEM;
826		goto bail;
827	}
828
829	for (i = 0; i < ARRAY_SIZE(idev->qp_table.map); i++) {
830		atomic_set(&idev->qp_table.map[i].n_free, BITS_PER_PAGE);
831		idev->qp_table.map[i].page = NULL;
832	}
833
834	ret = 0;
835
836bail:
837	return ret;
838}
839
840/**
841 * ipath_sqerror_qp - put a QP's send queue into an error state
842 * @qp: QP who's send queue will be put into an error state
843 * @wc: the WC responsible for putting the QP in this state
844 *
845 * Flushes the send work queue.
846 * The QP s_lock should be held.
847 */
848
849void ipath_sqerror_qp(struct ipath_qp *qp, struct ib_wc *wc)
850{
851	struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
852	struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
853
854	_VERBS_INFO("Send queue error on QP%d/%d: err: %d\n",
855		    qp->ibqp.qp_num, qp->remote_qpn, wc->status);
856
857	spin_lock(&dev->pending_lock);
858	/* XXX What if its already removed by the timeout code? */
859	if (!list_empty(&qp->timerwait))
860		list_del_init(&qp->timerwait);
861	if (!list_empty(&qp->piowait))
862		list_del_init(&qp->piowait);
863	spin_unlock(&dev->pending_lock);
864
865	ipath_cq_enter(to_icq(qp->ibqp.send_cq), wc, 1);
866	if (++qp->s_last >= qp->s_size)
867		qp->s_last = 0;
868
869	wc->status = IB_WC_WR_FLUSH_ERR;
870
871	while (qp->s_last != qp->s_head) {
872		wc->wr_id = wqe->wr.wr_id;
873		wc->opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
874		ipath_cq_enter(to_icq(qp->ibqp.send_cq), wc, 1);
875		if (++qp->s_last >= qp->s_size)
876			qp->s_last = 0;
877		wqe = get_swqe_ptr(qp, qp->s_last);
878	}
879	qp->s_cur = qp->s_tail = qp->s_head;
880	qp->state = IB_QPS_SQE;
881}
882
883/**
884 * ipath_get_credit - flush the send work queue of a QP
885 * @qp: the qp who's send work queue to flush
886 * @aeth: the Acknowledge Extended Transport Header
887 *
888 * The QP s_lock should be held.
889 */
890void ipath_get_credit(struct ipath_qp *qp, u32 aeth)
891{
892	u32 credit = (aeth >> IPATH_AETH_CREDIT_SHIFT) & IPATH_AETH_CREDIT_MASK;
893
894	/*
895	 * If the credit is invalid, we can send
896	 * as many packets as we like.  Otherwise, we have to
897	 * honor the credit field.
898	 */
899	if (credit == IPATH_AETH_CREDIT_INVAL)
900		qp->s_lsn = (u32) -1;
901	else if (qp->s_lsn != (u32) -1) {
902		/* Compute new LSN (i.e., MSN + credit) */
903		credit = (aeth + credit_table[credit]) & IPATH_MSN_MASK;
904		if (ipath_cmp24(credit, qp->s_lsn) > 0)
905			qp->s_lsn = credit;
906	}
907
908	/* Restart sending if it was blocked due to lack of credits. */
909	if (qp->s_cur != qp->s_head &&
910	    (qp->s_lsn == (u32) -1 ||
911	     ipath_cmp24(get_swqe_ptr(qp, qp->s_cur)->ssn,
912			 qp->s_lsn + 1) <= 0))
913		tasklet_hi_schedule(&qp->s_task);
914}
915