1 /*
2  * Copyright(c) 2016 Intel Corporation.
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * BSD LICENSE
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  *
24  *  - Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  *  - Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in
28  *    the documentation and/or other materials provided with the
29  *    distribution.
30  *  - Neither the name of Intel Corporation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45  *
46  */
47 
48 #include "hfi.h"
49 #include "verbs_txreq.h"
50 #include "qp.h"
51 #include "trace.h"
52 
53 #define TXREQ_LEN 24
54 
55 void hfi1_put_txreq(struct verbs_txreq *tx)
56 {
57 	struct hfi1_ibdev *dev;
58 	struct rvt_qp *qp;
59 	unsigned long flags;
60 	unsigned int seq;
61 	struct hfi1_qp_priv *priv;
62 
63 	qp = tx->qp;
64 	dev = to_idev(qp->ibqp.device);
65 
66 	if (tx->mr)
67 		rvt_put_mr(tx->mr);
68 
69 	sdma_txclean(dd_from_dev(dev), &tx->txreq);
70 
71 	/* Free verbs_txreq and return to slab cache */
72 	kmem_cache_free(dev->verbs_txreq_cache, tx);
73 
74 	do {
75 		seq = read_seqbegin(&dev->iowait_lock);
76 		if (!list_empty(&dev->txwait)) {
77 			struct iowait *wait;
78 
79 			write_seqlock_irqsave(&dev->iowait_lock, flags);
80 			wait = list_first_entry(&dev->txwait, struct iowait,
81 						list);
82 			qp = iowait_to_qp(wait);
83 			priv = qp->priv;
84 			list_del_init(&priv->s_iowait.list);
85 			/* refcount held until actual wake up */
86 			write_sequnlock_irqrestore(&dev->iowait_lock, flags);
87 			hfi1_qp_wakeup(qp, RVT_S_WAIT_TX);
88 			break;
89 		}
90 	} while (read_seqretry(&dev->iowait_lock, seq));
91 }
92 
93 struct verbs_txreq *__get_txreq(struct hfi1_ibdev *dev,
94 				struct rvt_qp *qp)
95 	__must_hold(&qp->s_lock)
96 {
97 	struct verbs_txreq *tx = ERR_PTR(-EBUSY);
98 
99 	write_seqlock(&dev->iowait_lock);
100 	if (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) {
101 		struct hfi1_qp_priv *priv;
102 
103 		tx = kmem_cache_alloc(dev->verbs_txreq_cache, GFP_ATOMIC);
104 		if (tx)
105 			goto out;
106 		priv = qp->priv;
107 		if (list_empty(&priv->s_iowait.list)) {
108 			dev->n_txwait++;
109 			qp->s_flags |= RVT_S_WAIT_TX;
110 			list_add_tail(&priv->s_iowait.list, &dev->txwait);
111 			trace_hfi1_qpsleep(qp, RVT_S_WAIT_TX);
112 			atomic_inc(&qp->refcount);
113 		}
114 		qp->s_flags &= ~RVT_S_BUSY;
115 	}
116 out:
117 	write_sequnlock(&dev->iowait_lock);
118 	return tx;
119 }
120 
121 static void verbs_txreq_kmem_cache_ctor(void *obj)
122 {
123 	struct verbs_txreq *tx = (struct verbs_txreq *)obj;
124 
125 	memset(tx, 0, sizeof(*tx));
126 }
127 
128 int verbs_txreq_init(struct hfi1_ibdev *dev)
129 {
130 	char buf[TXREQ_LEN];
131 	struct hfi1_devdata *dd = dd_from_dev(dev);
132 
133 	snprintf(buf, sizeof(buf), "hfi1_%u_vtxreq_cache", dd->unit);
134 	dev->verbs_txreq_cache = kmem_cache_create(buf,
135 						   sizeof(struct verbs_txreq),
136 						   0, SLAB_HWCACHE_ALIGN,
137 						   verbs_txreq_kmem_cache_ctor);
138 	if (!dev->verbs_txreq_cache)
139 		return -ENOMEM;
140 	return 0;
141 }
142 
143 void verbs_txreq_exit(struct hfi1_ibdev *dev)
144 {
145 	kmem_cache_destroy(dev->verbs_txreq_cache);
146 	dev->verbs_txreq_cache = NULL;
147 }
148