xref: /linux/drivers/infiniband/hw/qib/qib_qp.c (revision 8c749ce93ee69e789e46b3be98de9e0cbfcf8ed8)
1 /*
2  * Copyright (c) 2012, 2013 Intel Corporation.  All rights reserved.
3  * Copyright (c) 2006 - 2012 QLogic Corporation.  * All rights reserved.
4  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include <linux/err.h>
36 #include <linux/vmalloc.h>
37 #include <linux/jhash.h>
38 #ifdef CONFIG_DEBUG_FS
39 #include <linux/seq_file.h>
40 #endif
41 
42 #include "qib.h"
43 
44 #define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
45 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
46 
47 static inline unsigned mk_qpn(struct qib_qpn_table *qpt,
48 			      struct qpn_map *map, unsigned off)
49 {
50 	return (map - qpt->map) * BITS_PER_PAGE + off;
51 }
52 
53 static inline unsigned find_next_offset(struct qib_qpn_table *qpt,
54 					struct qpn_map *map, unsigned off,
55 					unsigned n)
56 {
57 	if (qpt->mask) {
58 		off++;
59 		if (((off & qpt->mask) >> 1) >= n)
60 			off = (off | qpt->mask) + 2;
61 	} else
62 		off = find_next_zero_bit(map->page, BITS_PER_PAGE, off);
63 	return off;
64 }
65 
66 /*
67  * Convert the AETH credit code into the number of credits.
68  */
69 static u32 credit_table[31] = {
70 	0,                      /* 0 */
71 	1,                      /* 1 */
72 	2,                      /* 2 */
73 	3,                      /* 3 */
74 	4,                      /* 4 */
75 	6,                      /* 5 */
76 	8,                      /* 6 */
77 	12,                     /* 7 */
78 	16,                     /* 8 */
79 	24,                     /* 9 */
80 	32,                     /* A */
81 	48,                     /* B */
82 	64,                     /* C */
83 	96,                     /* D */
84 	128,                    /* E */
85 	192,                    /* F */
86 	256,                    /* 10 */
87 	384,                    /* 11 */
88 	512,                    /* 12 */
89 	768,                    /* 13 */
90 	1024,                   /* 14 */
91 	1536,                   /* 15 */
92 	2048,                   /* 16 */
93 	3072,                   /* 17 */
94 	4096,                   /* 18 */
95 	6144,                   /* 19 */
96 	8192,                   /* 1A */
97 	12288,                  /* 1B */
98 	16384,                  /* 1C */
99 	24576,                  /* 1D */
100 	32768                   /* 1E */
101 };
102 
103 static void get_map_page(struct qib_qpn_table *qpt, struct qpn_map *map,
104 			 gfp_t gfp)
105 {
106 	unsigned long page = get_zeroed_page(gfp);
107 
108 	/*
109 	 * Free the page if someone raced with us installing it.
110 	 */
111 
112 	spin_lock(&qpt->lock);
113 	if (map->page)
114 		free_page(page);
115 	else
116 		map->page = (void *)page;
117 	spin_unlock(&qpt->lock);
118 }
119 
120 /*
121  * Allocate the next available QPN or
122  * zero/one for QP type IB_QPT_SMI/IB_QPT_GSI.
123  */
124 static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
125 		     enum ib_qp_type type, u8 port, gfp_t gfp)
126 {
127 	u32 i, offset, max_scan, qpn;
128 	struct qpn_map *map;
129 	u32 ret;
130 
131 	if (type == IB_QPT_SMI || type == IB_QPT_GSI) {
132 		unsigned n;
133 
134 		ret = type == IB_QPT_GSI;
135 		n = 1 << (ret + 2 * (port - 1));
136 		spin_lock(&qpt->lock);
137 		if (qpt->flags & n)
138 			ret = -EINVAL;
139 		else
140 			qpt->flags |= n;
141 		spin_unlock(&qpt->lock);
142 		goto bail;
143 	}
144 
145 	qpn = qpt->last + 2;
146 	if (qpn >= QPN_MAX)
147 		qpn = 2;
148 	if (qpt->mask && ((qpn & qpt->mask) >> 1) >= dd->n_krcv_queues)
149 		qpn = (qpn | qpt->mask) + 2;
150 	offset = qpn & BITS_PER_PAGE_MASK;
151 	map = &qpt->map[qpn / BITS_PER_PAGE];
152 	max_scan = qpt->nmaps - !offset;
153 	for (i = 0;;) {
154 		if (unlikely(!map->page)) {
155 			get_map_page(qpt, map, gfp);
156 			if (unlikely(!map->page))
157 				break;
158 		}
159 		do {
160 			if (!test_and_set_bit(offset, map->page)) {
161 				qpt->last = qpn;
162 				ret = qpn;
163 				goto bail;
164 			}
165 			offset = find_next_offset(qpt, map, offset,
166 				dd->n_krcv_queues);
167 			qpn = mk_qpn(qpt, map, offset);
168 			/*
169 			 * This test differs from alloc_pidmap().
170 			 * If find_next_offset() does find a zero
171 			 * bit, we don't need to check for QPN
172 			 * wrapping around past our starting QPN.
173 			 * We just need to be sure we don't loop
174 			 * forever.
175 			 */
176 		} while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
177 		/*
178 		 * In order to keep the number of pages allocated to a
179 		 * minimum, we scan the all existing pages before increasing
180 		 * the size of the bitmap table.
181 		 */
182 		if (++i > max_scan) {
183 			if (qpt->nmaps == QPNMAP_ENTRIES)
184 				break;
185 			map = &qpt->map[qpt->nmaps++];
186 			offset = 0;
187 		} else if (map < &qpt->map[qpt->nmaps]) {
188 			++map;
189 			offset = 0;
190 		} else {
191 			map = &qpt->map[0];
192 			offset = 2;
193 		}
194 		qpn = mk_qpn(qpt, map, offset);
195 	}
196 
197 	ret = -ENOMEM;
198 
199 bail:
200 	return ret;
201 }
202 
203 static void free_qpn(struct qib_qpn_table *qpt, u32 qpn)
204 {
205 	struct qpn_map *map;
206 
207 	map = qpt->map + qpn / BITS_PER_PAGE;
208 	if (map->page)
209 		clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
210 }
211 
212 static inline unsigned qpn_hash(struct qib_ibdev *dev, u32 qpn)
213 {
214 	return jhash_1word(qpn, dev->qp_rnd) &
215 		(dev->qp_table_size - 1);
216 }
217 
218 
219 /*
220  * Put the QP into the hash table.
221  * The hash table holds a reference to the QP.
222  */
223 static void insert_qp(struct qib_ibdev *dev, struct qib_qp *qp)
224 {
225 	struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
226 	unsigned long flags;
227 	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
228 
229 	atomic_inc(&qp->refcount);
230 	spin_lock_irqsave(&dev->qpt_lock, flags);
231 
232 	if (qp->ibqp.qp_num == 0)
233 		rcu_assign_pointer(ibp->qp0, qp);
234 	else if (qp->ibqp.qp_num == 1)
235 		rcu_assign_pointer(ibp->qp1, qp);
236 	else {
237 		qp->next = dev->qp_table[n];
238 		rcu_assign_pointer(dev->qp_table[n], qp);
239 	}
240 
241 	spin_unlock_irqrestore(&dev->qpt_lock, flags);
242 }
243 
244 /*
245  * Remove the QP from the table so it can't be found asynchronously by
246  * the receive interrupt routine.
247  */
248 static void remove_qp(struct qib_ibdev *dev, struct qib_qp *qp)
249 {
250 	struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
251 	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
252 	unsigned long flags;
253 	int removed = 1;
254 
255 	spin_lock_irqsave(&dev->qpt_lock, flags);
256 
257 	if (rcu_dereference_protected(ibp->qp0,
258 			lockdep_is_held(&dev->qpt_lock)) == qp) {
259 		RCU_INIT_POINTER(ibp->qp0, NULL);
260 	} else if (rcu_dereference_protected(ibp->qp1,
261 			lockdep_is_held(&dev->qpt_lock)) == qp) {
262 		RCU_INIT_POINTER(ibp->qp1, NULL);
263 	} else {
264 		struct qib_qp *q;
265 		struct qib_qp __rcu **qpp;
266 
267 		removed = 0;
268 		qpp = &dev->qp_table[n];
269 		for (; (q = rcu_dereference_protected(*qpp,
270 				lockdep_is_held(&dev->qpt_lock))) != NULL;
271 				qpp = &q->next)
272 			if (q == qp) {
273 				RCU_INIT_POINTER(*qpp,
274 					rcu_dereference_protected(qp->next,
275 					 lockdep_is_held(&dev->qpt_lock)));
276 				removed = 1;
277 				break;
278 			}
279 	}
280 
281 	spin_unlock_irqrestore(&dev->qpt_lock, flags);
282 	if (removed) {
283 		synchronize_rcu();
284 		atomic_dec(&qp->refcount);
285 	}
286 }
287 
288 /**
289  * qib_free_all_qps - check for QPs still in use
290  * @qpt: the QP table to empty
291  *
292  * There should not be any QPs still in use.
293  * Free memory for table.
294  */
295 unsigned qib_free_all_qps(struct qib_devdata *dd)
296 {
297 	struct qib_ibdev *dev = &dd->verbs_dev;
298 	unsigned long flags;
299 	struct qib_qp *qp;
300 	unsigned n, qp_inuse = 0;
301 
302 	for (n = 0; n < dd->num_pports; n++) {
303 		struct qib_ibport *ibp = &dd->pport[n].ibport_data;
304 
305 		if (!qib_mcast_tree_empty(ibp))
306 			qp_inuse++;
307 		rcu_read_lock();
308 		if (rcu_dereference(ibp->qp0))
309 			qp_inuse++;
310 		if (rcu_dereference(ibp->qp1))
311 			qp_inuse++;
312 		rcu_read_unlock();
313 	}
314 
315 	spin_lock_irqsave(&dev->qpt_lock, flags);
316 	for (n = 0; n < dev->qp_table_size; n++) {
317 		qp = rcu_dereference_protected(dev->qp_table[n],
318 			lockdep_is_held(&dev->qpt_lock));
319 		RCU_INIT_POINTER(dev->qp_table[n], NULL);
320 
321 		for (; qp; qp = rcu_dereference_protected(qp->next,
322 					lockdep_is_held(&dev->qpt_lock)))
323 			qp_inuse++;
324 	}
325 	spin_unlock_irqrestore(&dev->qpt_lock, flags);
326 	synchronize_rcu();
327 
328 	return qp_inuse;
329 }
330 
331 /**
332  * qib_lookup_qpn - return the QP with the given QPN
333  * @qpt: the QP table
334  * @qpn: the QP number to look up
335  *
336  * The caller is responsible for decrementing the QP reference count
337  * when done.
338  */
339 struct qib_qp *qib_lookup_qpn(struct qib_ibport *ibp, u32 qpn)
340 {
341 	struct qib_qp *qp = NULL;
342 
343 	rcu_read_lock();
344 	if (unlikely(qpn <= 1)) {
345 		if (qpn == 0)
346 			qp = rcu_dereference(ibp->qp0);
347 		else
348 			qp = rcu_dereference(ibp->qp1);
349 		if (qp)
350 			atomic_inc(&qp->refcount);
351 	} else {
352 		struct qib_ibdev *dev = &ppd_from_ibp(ibp)->dd->verbs_dev;
353 		unsigned n = qpn_hash(dev, qpn);
354 
355 		for (qp = rcu_dereference(dev->qp_table[n]); qp;
356 			qp = rcu_dereference(qp->next))
357 			if (qp->ibqp.qp_num == qpn) {
358 				atomic_inc(&qp->refcount);
359 				break;
360 			}
361 	}
362 	rcu_read_unlock();
363 	return qp;
364 }
365 
366 /**
367  * qib_reset_qp - initialize the QP state to the reset state
368  * @qp: the QP to reset
369  * @type: the QP type
370  */
371 static void qib_reset_qp(struct qib_qp *qp, enum ib_qp_type type)
372 {
373 	qp->remote_qpn = 0;
374 	qp->qkey = 0;
375 	qp->qp_access_flags = 0;
376 	atomic_set(&qp->s_dma_busy, 0);
377 	qp->s_flags &= QIB_S_SIGNAL_REQ_WR;
378 	qp->s_hdrwords = 0;
379 	qp->s_wqe = NULL;
380 	qp->s_draining = 0;
381 	qp->s_next_psn = 0;
382 	qp->s_last_psn = 0;
383 	qp->s_sending_psn = 0;
384 	qp->s_sending_hpsn = 0;
385 	qp->s_psn = 0;
386 	qp->r_psn = 0;
387 	qp->r_msn = 0;
388 	if (type == IB_QPT_RC) {
389 		qp->s_state = IB_OPCODE_RC_SEND_LAST;
390 		qp->r_state = IB_OPCODE_RC_SEND_LAST;
391 	} else {
392 		qp->s_state = IB_OPCODE_UC_SEND_LAST;
393 		qp->r_state = IB_OPCODE_UC_SEND_LAST;
394 	}
395 	qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
396 	qp->r_nak_state = 0;
397 	qp->r_aflags = 0;
398 	qp->r_flags = 0;
399 	qp->s_head = 0;
400 	qp->s_tail = 0;
401 	qp->s_cur = 0;
402 	qp->s_acked = 0;
403 	qp->s_last = 0;
404 	qp->s_ssn = 1;
405 	qp->s_lsn = 0;
406 	qp->s_mig_state = IB_MIG_MIGRATED;
407 	memset(qp->s_ack_queue, 0, sizeof(qp->s_ack_queue));
408 	qp->r_head_ack_queue = 0;
409 	qp->s_tail_ack_queue = 0;
410 	qp->s_num_rd_atomic = 0;
411 	if (qp->r_rq.wq) {
412 		qp->r_rq.wq->head = 0;
413 		qp->r_rq.wq->tail = 0;
414 	}
415 	qp->r_sge.num_sge = 0;
416 }
417 
418 static void clear_mr_refs(struct qib_qp *qp, int clr_sends)
419 {
420 	unsigned n;
421 
422 	if (test_and_clear_bit(QIB_R_REWIND_SGE, &qp->r_aflags))
423 		qib_put_ss(&qp->s_rdma_read_sge);
424 
425 	qib_put_ss(&qp->r_sge);
426 
427 	if (clr_sends) {
428 		while (qp->s_last != qp->s_head) {
429 			struct qib_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
430 			unsigned i;
431 
432 			for (i = 0; i < wqe->wr.num_sge; i++) {
433 				struct qib_sge *sge = &wqe->sg_list[i];
434 
435 				qib_put_mr(sge->mr);
436 			}
437 			if (qp->ibqp.qp_type == IB_QPT_UD ||
438 			    qp->ibqp.qp_type == IB_QPT_SMI ||
439 			    qp->ibqp.qp_type == IB_QPT_GSI)
440 				atomic_dec(&to_iah(wqe->ud_wr.ah)->refcount);
441 			if (++qp->s_last >= qp->s_size)
442 				qp->s_last = 0;
443 		}
444 		if (qp->s_rdma_mr) {
445 			qib_put_mr(qp->s_rdma_mr);
446 			qp->s_rdma_mr = NULL;
447 		}
448 	}
449 
450 	if (qp->ibqp.qp_type != IB_QPT_RC)
451 		return;
452 
453 	for (n = 0; n < ARRAY_SIZE(qp->s_ack_queue); n++) {
454 		struct qib_ack_entry *e = &qp->s_ack_queue[n];
455 
456 		if (e->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST &&
457 		    e->rdma_sge.mr) {
458 			qib_put_mr(e->rdma_sge.mr);
459 			e->rdma_sge.mr = NULL;
460 		}
461 	}
462 }
463 
464 /**
465  * qib_error_qp - put a QP into the error state
466  * @qp: the QP to put into the error state
467  * @err: the receive completion error to signal if a RWQE is active
468  *
469  * Flushes both send and receive work queues.
470  * Returns true if last WQE event should be generated.
471  * The QP r_lock and s_lock should be held and interrupts disabled.
472  * If we are already in error state, just return.
473  */
474 int qib_error_qp(struct qib_qp *qp, enum ib_wc_status err)
475 {
476 	struct qib_ibdev *dev = to_idev(qp->ibqp.device);
477 	struct ib_wc wc;
478 	int ret = 0;
479 
480 	if (qp->state == IB_QPS_ERR || qp->state == IB_QPS_RESET)
481 		goto bail;
482 
483 	qp->state = IB_QPS_ERR;
484 
485 	if (qp->s_flags & (QIB_S_TIMER | QIB_S_WAIT_RNR)) {
486 		qp->s_flags &= ~(QIB_S_TIMER | QIB_S_WAIT_RNR);
487 		del_timer(&qp->s_timer);
488 	}
489 
490 	if (qp->s_flags & QIB_S_ANY_WAIT_SEND)
491 		qp->s_flags &= ~QIB_S_ANY_WAIT_SEND;
492 
493 	spin_lock(&dev->pending_lock);
494 	if (!list_empty(&qp->iowait) && !(qp->s_flags & QIB_S_BUSY)) {
495 		qp->s_flags &= ~QIB_S_ANY_WAIT_IO;
496 		list_del_init(&qp->iowait);
497 	}
498 	spin_unlock(&dev->pending_lock);
499 
500 	if (!(qp->s_flags & QIB_S_BUSY)) {
501 		qp->s_hdrwords = 0;
502 		if (qp->s_rdma_mr) {
503 			qib_put_mr(qp->s_rdma_mr);
504 			qp->s_rdma_mr = NULL;
505 		}
506 		if (qp->s_tx) {
507 			qib_put_txreq(qp->s_tx);
508 			qp->s_tx = NULL;
509 		}
510 	}
511 
512 	/* Schedule the sending tasklet to drain the send work queue. */
513 	if (qp->s_last != qp->s_head)
514 		qib_schedule_send(qp);
515 
516 	clear_mr_refs(qp, 0);
517 
518 	memset(&wc, 0, sizeof(wc));
519 	wc.qp = &qp->ibqp;
520 	wc.opcode = IB_WC_RECV;
521 
522 	if (test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags)) {
523 		wc.wr_id = qp->r_wr_id;
524 		wc.status = err;
525 		qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
526 	}
527 	wc.status = IB_WC_WR_FLUSH_ERR;
528 
529 	if (qp->r_rq.wq) {
530 		struct qib_rwq *wq;
531 		u32 head;
532 		u32 tail;
533 
534 		spin_lock(&qp->r_rq.lock);
535 
536 		/* sanity check pointers before trusting them */
537 		wq = qp->r_rq.wq;
538 		head = wq->head;
539 		if (head >= qp->r_rq.size)
540 			head = 0;
541 		tail = wq->tail;
542 		if (tail >= qp->r_rq.size)
543 			tail = 0;
544 		while (tail != head) {
545 			wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
546 			if (++tail >= qp->r_rq.size)
547 				tail = 0;
548 			qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
549 		}
550 		wq->tail = tail;
551 
552 		spin_unlock(&qp->r_rq.lock);
553 	} else if (qp->ibqp.event_handler)
554 		ret = 1;
555 
556 bail:
557 	return ret;
558 }
559 
560 /**
561  * qib_modify_qp - modify the attributes of a queue pair
562  * @ibqp: the queue pair who's attributes we're modifying
563  * @attr: the new attributes
564  * @attr_mask: the mask of attributes to modify
565  * @udata: user data for libibverbs.so
566  *
567  * Returns 0 on success, otherwise returns an errno.
568  */
569 int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
570 		  int attr_mask, struct ib_udata *udata)
571 {
572 	struct qib_ibdev *dev = to_idev(ibqp->device);
573 	struct qib_qp *qp = to_iqp(ibqp);
574 	enum ib_qp_state cur_state, new_state;
575 	struct ib_event ev;
576 	int lastwqe = 0;
577 	int mig = 0;
578 	int ret;
579 	u32 pmtu = 0; /* for gcc warning only */
580 
581 	spin_lock_irq(&qp->r_lock);
582 	spin_lock(&qp->s_lock);
583 
584 	cur_state = attr_mask & IB_QP_CUR_STATE ?
585 		attr->cur_qp_state : qp->state;
586 	new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
587 
588 	if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
589 				attr_mask, IB_LINK_LAYER_UNSPECIFIED))
590 		goto inval;
591 
592 	if (attr_mask & IB_QP_AV) {
593 		if (attr->ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
594 			goto inval;
595 		if (qib_check_ah(qp->ibqp.device, &attr->ah_attr))
596 			goto inval;
597 	}
598 
599 	if (attr_mask & IB_QP_ALT_PATH) {
600 		if (attr->alt_ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
601 			goto inval;
602 		if (qib_check_ah(qp->ibqp.device, &attr->alt_ah_attr))
603 			goto inval;
604 		if (attr->alt_pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
605 			goto inval;
606 	}
607 
608 	if (attr_mask & IB_QP_PKEY_INDEX)
609 		if (attr->pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
610 			goto inval;
611 
612 	if (attr_mask & IB_QP_MIN_RNR_TIMER)
613 		if (attr->min_rnr_timer > 31)
614 			goto inval;
615 
616 	if (attr_mask & IB_QP_PORT)
617 		if (qp->ibqp.qp_type == IB_QPT_SMI ||
618 		    qp->ibqp.qp_type == IB_QPT_GSI ||
619 		    attr->port_num == 0 ||
620 		    attr->port_num > ibqp->device->phys_port_cnt)
621 			goto inval;
622 
623 	if (attr_mask & IB_QP_DEST_QPN)
624 		if (attr->dest_qp_num > QIB_QPN_MASK)
625 			goto inval;
626 
627 	if (attr_mask & IB_QP_RETRY_CNT)
628 		if (attr->retry_cnt > 7)
629 			goto inval;
630 
631 	if (attr_mask & IB_QP_RNR_RETRY)
632 		if (attr->rnr_retry > 7)
633 			goto inval;
634 
635 	/*
636 	 * Don't allow invalid path_mtu values.  OK to set greater
637 	 * than the active mtu (or even the max_cap, if we have tuned
638 	 * that to a small mtu.  We'll set qp->path_mtu
639 	 * to the lesser of requested attribute mtu and active,
640 	 * for packetizing messages.
641 	 * Note that the QP port has to be set in INIT and MTU in RTR.
642 	 */
643 	if (attr_mask & IB_QP_PATH_MTU) {
644 		struct qib_devdata *dd = dd_from_dev(dev);
645 		int mtu, pidx = qp->port_num - 1;
646 
647 		mtu = ib_mtu_enum_to_int(attr->path_mtu);
648 		if (mtu == -1)
649 			goto inval;
650 		if (mtu > dd->pport[pidx].ibmtu) {
651 			switch (dd->pport[pidx].ibmtu) {
652 			case 4096:
653 				pmtu = IB_MTU_4096;
654 				break;
655 			case 2048:
656 				pmtu = IB_MTU_2048;
657 				break;
658 			case 1024:
659 				pmtu = IB_MTU_1024;
660 				break;
661 			case 512:
662 				pmtu = IB_MTU_512;
663 				break;
664 			case 256:
665 				pmtu = IB_MTU_256;
666 				break;
667 			default:
668 				pmtu = IB_MTU_2048;
669 			}
670 		} else
671 			pmtu = attr->path_mtu;
672 	}
673 
674 	if (attr_mask & IB_QP_PATH_MIG_STATE) {
675 		if (attr->path_mig_state == IB_MIG_REARM) {
676 			if (qp->s_mig_state == IB_MIG_ARMED)
677 				goto inval;
678 			if (new_state != IB_QPS_RTS)
679 				goto inval;
680 		} else if (attr->path_mig_state == IB_MIG_MIGRATED) {
681 			if (qp->s_mig_state == IB_MIG_REARM)
682 				goto inval;
683 			if (new_state != IB_QPS_RTS && new_state != IB_QPS_SQD)
684 				goto inval;
685 			if (qp->s_mig_state == IB_MIG_ARMED)
686 				mig = 1;
687 		} else
688 			goto inval;
689 	}
690 
691 	if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
692 		if (attr->max_dest_rd_atomic > QIB_MAX_RDMA_ATOMIC)
693 			goto inval;
694 
695 	switch (new_state) {
696 	case IB_QPS_RESET:
697 		if (qp->state != IB_QPS_RESET) {
698 			qp->state = IB_QPS_RESET;
699 			spin_lock(&dev->pending_lock);
700 			if (!list_empty(&qp->iowait))
701 				list_del_init(&qp->iowait);
702 			spin_unlock(&dev->pending_lock);
703 			qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
704 			spin_unlock(&qp->s_lock);
705 			spin_unlock_irq(&qp->r_lock);
706 			/* Stop the sending work queue and retry timer */
707 			cancel_work_sync(&qp->s_work);
708 			del_timer_sync(&qp->s_timer);
709 			wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
710 			if (qp->s_tx) {
711 				qib_put_txreq(qp->s_tx);
712 				qp->s_tx = NULL;
713 			}
714 			remove_qp(dev, qp);
715 			wait_event(qp->wait, !atomic_read(&qp->refcount));
716 			spin_lock_irq(&qp->r_lock);
717 			spin_lock(&qp->s_lock);
718 			clear_mr_refs(qp, 1);
719 			qib_reset_qp(qp, ibqp->qp_type);
720 		}
721 		break;
722 
723 	case IB_QPS_RTR:
724 		/* Allow event to retrigger if QP set to RTR more than once */
725 		qp->r_flags &= ~QIB_R_COMM_EST;
726 		qp->state = new_state;
727 		break;
728 
729 	case IB_QPS_SQD:
730 		qp->s_draining = qp->s_last != qp->s_cur;
731 		qp->state = new_state;
732 		break;
733 
734 	case IB_QPS_SQE:
735 		if (qp->ibqp.qp_type == IB_QPT_RC)
736 			goto inval;
737 		qp->state = new_state;
738 		break;
739 
740 	case IB_QPS_ERR:
741 		lastwqe = qib_error_qp(qp, IB_WC_WR_FLUSH_ERR);
742 		break;
743 
744 	default:
745 		qp->state = new_state;
746 		break;
747 	}
748 
749 	if (attr_mask & IB_QP_PKEY_INDEX)
750 		qp->s_pkey_index = attr->pkey_index;
751 
752 	if (attr_mask & IB_QP_PORT)
753 		qp->port_num = attr->port_num;
754 
755 	if (attr_mask & IB_QP_DEST_QPN)
756 		qp->remote_qpn = attr->dest_qp_num;
757 
758 	if (attr_mask & IB_QP_SQ_PSN) {
759 		qp->s_next_psn = attr->sq_psn & QIB_PSN_MASK;
760 		qp->s_psn = qp->s_next_psn;
761 		qp->s_sending_psn = qp->s_next_psn;
762 		qp->s_last_psn = qp->s_next_psn - 1;
763 		qp->s_sending_hpsn = qp->s_last_psn;
764 	}
765 
766 	if (attr_mask & IB_QP_RQ_PSN)
767 		qp->r_psn = attr->rq_psn & QIB_PSN_MASK;
768 
769 	if (attr_mask & IB_QP_ACCESS_FLAGS)
770 		qp->qp_access_flags = attr->qp_access_flags;
771 
772 	if (attr_mask & IB_QP_AV) {
773 		qp->remote_ah_attr = attr->ah_attr;
774 		qp->s_srate = attr->ah_attr.static_rate;
775 	}
776 
777 	if (attr_mask & IB_QP_ALT_PATH) {
778 		qp->alt_ah_attr = attr->alt_ah_attr;
779 		qp->s_alt_pkey_index = attr->alt_pkey_index;
780 	}
781 
782 	if (attr_mask & IB_QP_PATH_MIG_STATE) {
783 		qp->s_mig_state = attr->path_mig_state;
784 		if (mig) {
785 			qp->remote_ah_attr = qp->alt_ah_attr;
786 			qp->port_num = qp->alt_ah_attr.port_num;
787 			qp->s_pkey_index = qp->s_alt_pkey_index;
788 		}
789 	}
790 
791 	if (attr_mask & IB_QP_PATH_MTU) {
792 		qp->path_mtu = pmtu;
793 		qp->pmtu = ib_mtu_enum_to_int(pmtu);
794 	}
795 
796 	if (attr_mask & IB_QP_RETRY_CNT) {
797 		qp->s_retry_cnt = attr->retry_cnt;
798 		qp->s_retry = attr->retry_cnt;
799 	}
800 
801 	if (attr_mask & IB_QP_RNR_RETRY) {
802 		qp->s_rnr_retry_cnt = attr->rnr_retry;
803 		qp->s_rnr_retry = attr->rnr_retry;
804 	}
805 
806 	if (attr_mask & IB_QP_MIN_RNR_TIMER)
807 		qp->r_min_rnr_timer = attr->min_rnr_timer;
808 
809 	if (attr_mask & IB_QP_TIMEOUT) {
810 		qp->timeout = attr->timeout;
811 		qp->timeout_jiffies =
812 			usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
813 				1000UL);
814 	}
815 
816 	if (attr_mask & IB_QP_QKEY)
817 		qp->qkey = attr->qkey;
818 
819 	if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
820 		qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
821 
822 	if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
823 		qp->s_max_rd_atomic = attr->max_rd_atomic;
824 
825 	spin_unlock(&qp->s_lock);
826 	spin_unlock_irq(&qp->r_lock);
827 
828 	if (cur_state == IB_QPS_RESET && new_state == IB_QPS_INIT)
829 		insert_qp(dev, qp);
830 
831 	if (lastwqe) {
832 		ev.device = qp->ibqp.device;
833 		ev.element.qp = &qp->ibqp;
834 		ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
835 		qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
836 	}
837 	if (mig) {
838 		ev.device = qp->ibqp.device;
839 		ev.element.qp = &qp->ibqp;
840 		ev.event = IB_EVENT_PATH_MIG;
841 		qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
842 	}
843 	ret = 0;
844 	goto bail;
845 
846 inval:
847 	spin_unlock(&qp->s_lock);
848 	spin_unlock_irq(&qp->r_lock);
849 	ret = -EINVAL;
850 
851 bail:
852 	return ret;
853 }
854 
855 int qib_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
856 		 int attr_mask, struct ib_qp_init_attr *init_attr)
857 {
858 	struct qib_qp *qp = to_iqp(ibqp);
859 
860 	attr->qp_state = qp->state;
861 	attr->cur_qp_state = attr->qp_state;
862 	attr->path_mtu = qp->path_mtu;
863 	attr->path_mig_state = qp->s_mig_state;
864 	attr->qkey = qp->qkey;
865 	attr->rq_psn = qp->r_psn & QIB_PSN_MASK;
866 	attr->sq_psn = qp->s_next_psn & QIB_PSN_MASK;
867 	attr->dest_qp_num = qp->remote_qpn;
868 	attr->qp_access_flags = qp->qp_access_flags;
869 	attr->cap.max_send_wr = qp->s_size - 1;
870 	attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
871 	attr->cap.max_send_sge = qp->s_max_sge;
872 	attr->cap.max_recv_sge = qp->r_rq.max_sge;
873 	attr->cap.max_inline_data = 0;
874 	attr->ah_attr = qp->remote_ah_attr;
875 	attr->alt_ah_attr = qp->alt_ah_attr;
876 	attr->pkey_index = qp->s_pkey_index;
877 	attr->alt_pkey_index = qp->s_alt_pkey_index;
878 	attr->en_sqd_async_notify = 0;
879 	attr->sq_draining = qp->s_draining;
880 	attr->max_rd_atomic = qp->s_max_rd_atomic;
881 	attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
882 	attr->min_rnr_timer = qp->r_min_rnr_timer;
883 	attr->port_num = qp->port_num;
884 	attr->timeout = qp->timeout;
885 	attr->retry_cnt = qp->s_retry_cnt;
886 	attr->rnr_retry = qp->s_rnr_retry_cnt;
887 	attr->alt_port_num = qp->alt_ah_attr.port_num;
888 	attr->alt_timeout = qp->alt_timeout;
889 
890 	init_attr->event_handler = qp->ibqp.event_handler;
891 	init_attr->qp_context = qp->ibqp.qp_context;
892 	init_attr->send_cq = qp->ibqp.send_cq;
893 	init_attr->recv_cq = qp->ibqp.recv_cq;
894 	init_attr->srq = qp->ibqp.srq;
895 	init_attr->cap = attr->cap;
896 	if (qp->s_flags & QIB_S_SIGNAL_REQ_WR)
897 		init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
898 	else
899 		init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
900 	init_attr->qp_type = qp->ibqp.qp_type;
901 	init_attr->port_num = qp->port_num;
902 	return 0;
903 }
904 
905 /**
906  * qib_compute_aeth - compute the AETH (syndrome + MSN)
907  * @qp: the queue pair to compute the AETH for
908  *
909  * Returns the AETH.
910  */
911 __be32 qib_compute_aeth(struct qib_qp *qp)
912 {
913 	u32 aeth = qp->r_msn & QIB_MSN_MASK;
914 
915 	if (qp->ibqp.srq) {
916 		/*
917 		 * Shared receive queues don't generate credits.
918 		 * Set the credit field to the invalid value.
919 		 */
920 		aeth |= QIB_AETH_CREDIT_INVAL << QIB_AETH_CREDIT_SHIFT;
921 	} else {
922 		u32 min, max, x;
923 		u32 credits;
924 		struct qib_rwq *wq = qp->r_rq.wq;
925 		u32 head;
926 		u32 tail;
927 
928 		/* sanity check pointers before trusting them */
929 		head = wq->head;
930 		if (head >= qp->r_rq.size)
931 			head = 0;
932 		tail = wq->tail;
933 		if (tail >= qp->r_rq.size)
934 			tail = 0;
935 		/*
936 		 * Compute the number of credits available (RWQEs).
937 		 * XXX Not holding the r_rq.lock here so there is a small
938 		 * chance that the pair of reads are not atomic.
939 		 */
940 		credits = head - tail;
941 		if ((int)credits < 0)
942 			credits += qp->r_rq.size;
943 		/*
944 		 * Binary search the credit table to find the code to
945 		 * use.
946 		 */
947 		min = 0;
948 		max = 31;
949 		for (;;) {
950 			x = (min + max) / 2;
951 			if (credit_table[x] == credits)
952 				break;
953 			if (credit_table[x] > credits)
954 				max = x;
955 			else if (min == x)
956 				break;
957 			else
958 				min = x;
959 		}
960 		aeth |= x << QIB_AETH_CREDIT_SHIFT;
961 	}
962 	return cpu_to_be32(aeth);
963 }
964 
965 /**
966  * qib_create_qp - create a queue pair for a device
967  * @ibpd: the protection domain who's device we create the queue pair for
968  * @init_attr: the attributes of the queue pair
969  * @udata: user data for libibverbs.so
970  *
971  * Returns the queue pair on success, otherwise returns an errno.
972  *
973  * Called by the ib_create_qp() core verbs function.
974  */
975 struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
976 			    struct ib_qp_init_attr *init_attr,
977 			    struct ib_udata *udata)
978 {
979 	struct qib_qp *qp;
980 	int err;
981 	struct qib_swqe *swq = NULL;
982 	struct qib_ibdev *dev;
983 	struct qib_devdata *dd;
984 	size_t sz;
985 	size_t sg_list_sz;
986 	struct ib_qp *ret;
987 	gfp_t gfp;
988 
989 
990 	if (init_attr->cap.max_send_sge > ib_qib_max_sges ||
991 	    init_attr->cap.max_send_wr > ib_qib_max_qp_wrs ||
992 	    init_attr->create_flags & ~(IB_QP_CREATE_USE_GFP_NOIO))
993 		return ERR_PTR(-EINVAL);
994 
995 	/* GFP_NOIO is applicable in RC QPs only */
996 	if (init_attr->create_flags & IB_QP_CREATE_USE_GFP_NOIO &&
997 	    init_attr->qp_type != IB_QPT_RC)
998 		return ERR_PTR(-EINVAL);
999 
1000 	gfp = init_attr->create_flags & IB_QP_CREATE_USE_GFP_NOIO ?
1001 			GFP_NOIO : GFP_KERNEL;
1002 
1003 	/* Check receive queue parameters if no SRQ is specified. */
1004 	if (!init_attr->srq) {
1005 		if (init_attr->cap.max_recv_sge > ib_qib_max_sges ||
1006 		    init_attr->cap.max_recv_wr > ib_qib_max_qp_wrs) {
1007 			ret = ERR_PTR(-EINVAL);
1008 			goto bail;
1009 		}
1010 		if (init_attr->cap.max_send_sge +
1011 		    init_attr->cap.max_send_wr +
1012 		    init_attr->cap.max_recv_sge +
1013 		    init_attr->cap.max_recv_wr == 0) {
1014 			ret = ERR_PTR(-EINVAL);
1015 			goto bail;
1016 		}
1017 	}
1018 
1019 	switch (init_attr->qp_type) {
1020 	case IB_QPT_SMI:
1021 	case IB_QPT_GSI:
1022 		if (init_attr->port_num == 0 ||
1023 		    init_attr->port_num > ibpd->device->phys_port_cnt) {
1024 			ret = ERR_PTR(-EINVAL);
1025 			goto bail;
1026 		}
1027 	case IB_QPT_UC:
1028 	case IB_QPT_RC:
1029 	case IB_QPT_UD:
1030 		sz = sizeof(struct qib_sge) *
1031 			init_attr->cap.max_send_sge +
1032 			sizeof(struct qib_swqe);
1033 		swq = __vmalloc((init_attr->cap.max_send_wr + 1) * sz,
1034 				gfp, PAGE_KERNEL);
1035 		if (swq == NULL) {
1036 			ret = ERR_PTR(-ENOMEM);
1037 			goto bail;
1038 		}
1039 		sz = sizeof(*qp);
1040 		sg_list_sz = 0;
1041 		if (init_attr->srq) {
1042 			struct qib_srq *srq = to_isrq(init_attr->srq);
1043 
1044 			if (srq->rq.max_sge > 1)
1045 				sg_list_sz = sizeof(*qp->r_sg_list) *
1046 					(srq->rq.max_sge - 1);
1047 		} else if (init_attr->cap.max_recv_sge > 1)
1048 			sg_list_sz = sizeof(*qp->r_sg_list) *
1049 				(init_attr->cap.max_recv_sge - 1);
1050 		qp = kzalloc(sz + sg_list_sz, gfp);
1051 		if (!qp) {
1052 			ret = ERR_PTR(-ENOMEM);
1053 			goto bail_swq;
1054 		}
1055 		RCU_INIT_POINTER(qp->next, NULL);
1056 		qp->s_hdr = kzalloc(sizeof(*qp->s_hdr), gfp);
1057 		if (!qp->s_hdr) {
1058 			ret = ERR_PTR(-ENOMEM);
1059 			goto bail_qp;
1060 		}
1061 		qp->timeout_jiffies =
1062 			usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
1063 				1000UL);
1064 		if (init_attr->srq)
1065 			sz = 0;
1066 		else {
1067 			qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
1068 			qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
1069 			sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
1070 				sizeof(struct qib_rwqe);
1071 			if (gfp != GFP_NOIO)
1072 				qp->r_rq.wq = vmalloc_user(
1073 						sizeof(struct qib_rwq) +
1074 						qp->r_rq.size * sz);
1075 			else
1076 				qp->r_rq.wq = __vmalloc(
1077 						sizeof(struct qib_rwq) +
1078 						qp->r_rq.size * sz,
1079 						gfp, PAGE_KERNEL);
1080 
1081 			if (!qp->r_rq.wq) {
1082 				ret = ERR_PTR(-ENOMEM);
1083 				goto bail_qp;
1084 			}
1085 		}
1086 
1087 		/*
1088 		 * ib_create_qp() will initialize qp->ibqp
1089 		 * except for qp->ibqp.qp_num.
1090 		 */
1091 		spin_lock_init(&qp->r_lock);
1092 		spin_lock_init(&qp->s_lock);
1093 		spin_lock_init(&qp->r_rq.lock);
1094 		atomic_set(&qp->refcount, 0);
1095 		init_waitqueue_head(&qp->wait);
1096 		init_waitqueue_head(&qp->wait_dma);
1097 		init_timer(&qp->s_timer);
1098 		qp->s_timer.data = (unsigned long)qp;
1099 		INIT_WORK(&qp->s_work, qib_do_send);
1100 		INIT_LIST_HEAD(&qp->iowait);
1101 		INIT_LIST_HEAD(&qp->rspwait);
1102 		qp->state = IB_QPS_RESET;
1103 		qp->s_wq = swq;
1104 		qp->s_size = init_attr->cap.max_send_wr + 1;
1105 		qp->s_max_sge = init_attr->cap.max_send_sge;
1106 		if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
1107 			qp->s_flags = QIB_S_SIGNAL_REQ_WR;
1108 		dev = to_idev(ibpd->device);
1109 		dd = dd_from_dev(dev);
1110 		err = alloc_qpn(dd, &dev->qpn_table, init_attr->qp_type,
1111 				init_attr->port_num, gfp);
1112 		if (err < 0) {
1113 			ret = ERR_PTR(err);
1114 			vfree(qp->r_rq.wq);
1115 			goto bail_qp;
1116 		}
1117 		qp->ibqp.qp_num = err;
1118 		qp->port_num = init_attr->port_num;
1119 		qib_reset_qp(qp, init_attr->qp_type);
1120 		break;
1121 
1122 	default:
1123 		/* Don't support raw QPs */
1124 		ret = ERR_PTR(-ENOSYS);
1125 		goto bail;
1126 	}
1127 
1128 	init_attr->cap.max_inline_data = 0;
1129 
1130 	/*
1131 	 * Return the address of the RWQ as the offset to mmap.
1132 	 * See qib_mmap() for details.
1133 	 */
1134 	if (udata && udata->outlen >= sizeof(__u64)) {
1135 		if (!qp->r_rq.wq) {
1136 			__u64 offset = 0;
1137 
1138 			err = ib_copy_to_udata(udata, &offset,
1139 					       sizeof(offset));
1140 			if (err) {
1141 				ret = ERR_PTR(err);
1142 				goto bail_ip;
1143 			}
1144 		} else {
1145 			u32 s = sizeof(struct qib_rwq) + qp->r_rq.size * sz;
1146 
1147 			qp->ip = qib_create_mmap_info(dev, s,
1148 						      ibpd->uobject->context,
1149 						      qp->r_rq.wq);
1150 			if (!qp->ip) {
1151 				ret = ERR_PTR(-ENOMEM);
1152 				goto bail_ip;
1153 			}
1154 
1155 			err = ib_copy_to_udata(udata, &(qp->ip->offset),
1156 					       sizeof(qp->ip->offset));
1157 			if (err) {
1158 				ret = ERR_PTR(err);
1159 				goto bail_ip;
1160 			}
1161 		}
1162 	}
1163 
1164 	spin_lock(&dev->n_qps_lock);
1165 	if (dev->n_qps_allocated == ib_qib_max_qps) {
1166 		spin_unlock(&dev->n_qps_lock);
1167 		ret = ERR_PTR(-ENOMEM);
1168 		goto bail_ip;
1169 	}
1170 
1171 	dev->n_qps_allocated++;
1172 	spin_unlock(&dev->n_qps_lock);
1173 
1174 	if (qp->ip) {
1175 		spin_lock_irq(&dev->pending_lock);
1176 		list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
1177 		spin_unlock_irq(&dev->pending_lock);
1178 	}
1179 
1180 	ret = &qp->ibqp;
1181 	goto bail;
1182 
1183 bail_ip:
1184 	if (qp->ip)
1185 		kref_put(&qp->ip->ref, qib_release_mmap_info);
1186 	else
1187 		vfree(qp->r_rq.wq);
1188 	free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
1189 bail_qp:
1190 	kfree(qp->s_hdr);
1191 	kfree(qp);
1192 bail_swq:
1193 	vfree(swq);
1194 bail:
1195 	return ret;
1196 }
1197 
1198 /**
1199  * qib_destroy_qp - destroy a queue pair
1200  * @ibqp: the queue pair to destroy
1201  *
1202  * Returns 0 on success.
1203  *
1204  * Note that this can be called while the QP is actively sending or
1205  * receiving!
1206  */
1207 int qib_destroy_qp(struct ib_qp *ibqp)
1208 {
1209 	struct qib_qp *qp = to_iqp(ibqp);
1210 	struct qib_ibdev *dev = to_idev(ibqp->device);
1211 
1212 	/* Make sure HW and driver activity is stopped. */
1213 	spin_lock_irq(&qp->s_lock);
1214 	if (qp->state != IB_QPS_RESET) {
1215 		qp->state = IB_QPS_RESET;
1216 		spin_lock(&dev->pending_lock);
1217 		if (!list_empty(&qp->iowait))
1218 			list_del_init(&qp->iowait);
1219 		spin_unlock(&dev->pending_lock);
1220 		qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
1221 		spin_unlock_irq(&qp->s_lock);
1222 		cancel_work_sync(&qp->s_work);
1223 		del_timer_sync(&qp->s_timer);
1224 		wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
1225 		if (qp->s_tx) {
1226 			qib_put_txreq(qp->s_tx);
1227 			qp->s_tx = NULL;
1228 		}
1229 		remove_qp(dev, qp);
1230 		wait_event(qp->wait, !atomic_read(&qp->refcount));
1231 		clear_mr_refs(qp, 1);
1232 	} else
1233 		spin_unlock_irq(&qp->s_lock);
1234 
1235 	/* all user's cleaned up, mark it available */
1236 	free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
1237 	spin_lock(&dev->n_qps_lock);
1238 	dev->n_qps_allocated--;
1239 	spin_unlock(&dev->n_qps_lock);
1240 
1241 	if (qp->ip)
1242 		kref_put(&qp->ip->ref, qib_release_mmap_info);
1243 	else
1244 		vfree(qp->r_rq.wq);
1245 	vfree(qp->s_wq);
1246 	kfree(qp->s_hdr);
1247 	kfree(qp);
1248 	return 0;
1249 }
1250 
1251 /**
1252  * qib_init_qpn_table - initialize the QP number table for a device
1253  * @qpt: the QPN table
1254  */
1255 void qib_init_qpn_table(struct qib_devdata *dd, struct qib_qpn_table *qpt)
1256 {
1257 	spin_lock_init(&qpt->lock);
1258 	qpt->last = 1;          /* start with QPN 2 */
1259 	qpt->nmaps = 1;
1260 	qpt->mask = dd->qpn_mask;
1261 }
1262 
1263 /**
1264  * qib_free_qpn_table - free the QP number table for a device
1265  * @qpt: the QPN table
1266  */
1267 void qib_free_qpn_table(struct qib_qpn_table *qpt)
1268 {
1269 	int i;
1270 
1271 	for (i = 0; i < ARRAY_SIZE(qpt->map); i++)
1272 		if (qpt->map[i].page)
1273 			free_page((unsigned long) qpt->map[i].page);
1274 }
1275 
1276 /**
1277  * qib_get_credit - flush the send work queue of a QP
1278  * @qp: the qp who's send work queue to flush
1279  * @aeth: the Acknowledge Extended Transport Header
1280  *
1281  * The QP s_lock should be held.
1282  */
1283 void qib_get_credit(struct qib_qp *qp, u32 aeth)
1284 {
1285 	u32 credit = (aeth >> QIB_AETH_CREDIT_SHIFT) & QIB_AETH_CREDIT_MASK;
1286 
1287 	/*
1288 	 * If the credit is invalid, we can send
1289 	 * as many packets as we like.  Otherwise, we have to
1290 	 * honor the credit field.
1291 	 */
1292 	if (credit == QIB_AETH_CREDIT_INVAL) {
1293 		if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
1294 			qp->s_flags |= QIB_S_UNLIMITED_CREDIT;
1295 			if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
1296 				qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
1297 				qib_schedule_send(qp);
1298 			}
1299 		}
1300 	} else if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
1301 		/* Compute new LSN (i.e., MSN + credit) */
1302 		credit = (aeth + credit_table[credit]) & QIB_MSN_MASK;
1303 		if (qib_cmp24(credit, qp->s_lsn) > 0) {
1304 			qp->s_lsn = credit;
1305 			if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
1306 				qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
1307 				qib_schedule_send(qp);
1308 			}
1309 		}
1310 	}
1311 }
1312 
1313 #ifdef CONFIG_DEBUG_FS
1314 
1315 struct qib_qp_iter {
1316 	struct qib_ibdev *dev;
1317 	struct qib_qp *qp;
1318 	int n;
1319 };
1320 
1321 struct qib_qp_iter *qib_qp_iter_init(struct qib_ibdev *dev)
1322 {
1323 	struct qib_qp_iter *iter;
1324 
1325 	iter = kzalloc(sizeof(*iter), GFP_KERNEL);
1326 	if (!iter)
1327 		return NULL;
1328 
1329 	iter->dev = dev;
1330 	if (qib_qp_iter_next(iter)) {
1331 		kfree(iter);
1332 		return NULL;
1333 	}
1334 
1335 	return iter;
1336 }
1337 
1338 int qib_qp_iter_next(struct qib_qp_iter *iter)
1339 {
1340 	struct qib_ibdev *dev = iter->dev;
1341 	int n = iter->n;
1342 	int ret = 1;
1343 	struct qib_qp *pqp = iter->qp;
1344 	struct qib_qp *qp;
1345 
1346 	for (; n < dev->qp_table_size; n++) {
1347 		if (pqp)
1348 			qp = rcu_dereference(pqp->next);
1349 		else
1350 			qp = rcu_dereference(dev->qp_table[n]);
1351 		pqp = qp;
1352 		if (qp) {
1353 			iter->qp = qp;
1354 			iter->n = n;
1355 			return 0;
1356 		}
1357 	}
1358 	return ret;
1359 }
1360 
1361 static const char * const qp_type_str[] = {
1362 	"SMI", "GSI", "RC", "UC", "UD",
1363 };
1364 
1365 void qib_qp_iter_print(struct seq_file *s, struct qib_qp_iter *iter)
1366 {
1367 	struct qib_swqe *wqe;
1368 	struct qib_qp *qp = iter->qp;
1369 
1370 	wqe = get_swqe_ptr(qp, qp->s_last);
1371 	seq_printf(s,
1372 		   "N %d QP%u %s %u %u %u f=%x %u %u %u %u %u PSN %x %x %x %x %x (%u %u %u %u %u %u) QP%u LID %x\n",
1373 		   iter->n,
1374 		   qp->ibqp.qp_num,
1375 		   qp_type_str[qp->ibqp.qp_type],
1376 		   qp->state,
1377 		   wqe->wr.opcode,
1378 		   qp->s_hdrwords,
1379 		   qp->s_flags,
1380 		   atomic_read(&qp->s_dma_busy),
1381 		   !list_empty(&qp->iowait),
1382 		   qp->timeout,
1383 		   wqe->ssn,
1384 		   qp->s_lsn,
1385 		   qp->s_last_psn,
1386 		   qp->s_psn, qp->s_next_psn,
1387 		   qp->s_sending_psn, qp->s_sending_hpsn,
1388 		   qp->s_last, qp->s_acked, qp->s_cur,
1389 		   qp->s_tail, qp->s_head, qp->s_size,
1390 		   qp->remote_qpn,
1391 		   qp->remote_ah_attr.dlid);
1392 }
1393 
1394 #endif
1395