1 /*
2 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
3 * Copyright (c) 2015 System Fabric Works, 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 retailuce 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/vmalloc.h>
35 #include "rxe.h"
36 #include "rxe_loc.h"
37 #include "rxe_queue.h"
38
do_mmap_info(struct rxe_dev * rxe,struct mminfo __user * outbuf,struct ib_udata * udata,struct rxe_queue_buf * buf,size_t buf_size,struct rxe_mmap_info ** ip_p)39 int do_mmap_info(struct rxe_dev *rxe, struct mminfo __user *outbuf,
40 struct ib_udata *udata, struct rxe_queue_buf *buf,
41 size_t buf_size, struct rxe_mmap_info **ip_p)
42 {
43 int err;
44 struct rxe_mmap_info *ip = NULL;
45
46 if (outbuf) {
47 ip = rxe_create_mmap_info(rxe, buf_size, udata, buf);
48 if (!ip)
49 goto err1;
50
51 err = copy_to_user(outbuf, &ip->info, sizeof(ip->info));
52 if (err)
53 goto err2;
54
55 spin_lock_bh(&rxe->pending_lock);
56 list_add(&ip->pending_mmaps, &rxe->pending_mmaps);
57 spin_unlock_bh(&rxe->pending_lock);
58 }
59
60 *ip_p = ip;
61
62 return 0;
63
64 err2:
65 kfree(ip);
66 err1:
67 return -EINVAL;
68 }
69
rxe_queue_reset(struct rxe_queue * q)70 inline void rxe_queue_reset(struct rxe_queue *q)
71 {
72 /* queue is comprised from header and the memory
73 * of the actual queue. See "struct rxe_queue_buf" in rxe_queue.h
74 * reset only the queue itself and not the management header
75 */
76 memset(q->buf->data, 0, q->buf_size - sizeof(struct rxe_queue_buf));
77 }
78
rxe_queue_init(struct rxe_dev * rxe,int * num_elem,unsigned int elem_size)79 struct rxe_queue *rxe_queue_init(struct rxe_dev *rxe,
80 int *num_elem,
81 unsigned int elem_size)
82 {
83 struct rxe_queue *q;
84 size_t buf_size;
85 unsigned int num_slots;
86
87 /* num_elem == 0 is allowed, but uninteresting */
88 if (*num_elem < 0)
89 goto err1;
90
91 q = kmalloc(sizeof(*q), GFP_KERNEL);
92 if (!q)
93 goto err1;
94
95 q->rxe = rxe;
96
97 /* used in resize, only need to copy used part of queue */
98 q->elem_size = elem_size;
99
100 /* pad element up to at least a cacheline and always a power of 2 */
101 if (elem_size < cache_line_size())
102 elem_size = cache_line_size();
103 elem_size = roundup_pow_of_two(elem_size);
104
105 q->log2_elem_size = order_base_2(elem_size);
106
107 num_slots = *num_elem + 1;
108 num_slots = roundup_pow_of_two(num_slots);
109 q->index_mask = num_slots - 1;
110
111 buf_size = sizeof(struct rxe_queue_buf) + num_slots * elem_size;
112
113 q->buf = vmalloc_user(buf_size);
114 if (!q->buf)
115 goto err2;
116
117 q->buf->log2_elem_size = q->log2_elem_size;
118 q->buf->index_mask = q->index_mask;
119
120 q->buf_size = buf_size;
121
122 *num_elem = num_slots - 1;
123 return q;
124
125 err2:
126 kfree(q);
127 err1:
128 return NULL;
129 }
130
131 /* copies elements from original q to new q and then swaps the contents of the
132 * two q headers. This is so that if anyone is holding a pointer to q it will
133 * still work
134 */
resize_finish(struct rxe_queue * q,struct rxe_queue * new_q,unsigned int num_elem)135 static int resize_finish(struct rxe_queue *q, struct rxe_queue *new_q,
136 unsigned int num_elem)
137 {
138 if (!queue_empty(q) && (num_elem < queue_count(q)))
139 return -EINVAL;
140
141 while (!queue_empty(q)) {
142 memcpy(producer_addr(new_q), consumer_addr(q),
143 new_q->elem_size);
144 advance_producer(new_q);
145 advance_consumer(q);
146 }
147
148 swap(*q, *new_q);
149
150 return 0;
151 }
152
rxe_queue_resize(struct rxe_queue * q,unsigned int * num_elem_p,unsigned int elem_size,struct ib_udata * udata,struct mminfo __user * outbuf,spinlock_t * producer_lock,spinlock_t * consumer_lock)153 int rxe_queue_resize(struct rxe_queue *q, unsigned int *num_elem_p,
154 unsigned int elem_size, struct ib_udata *udata,
155 struct mminfo __user *outbuf, spinlock_t *producer_lock,
156 spinlock_t *consumer_lock)
157 {
158 struct rxe_queue *new_q;
159 unsigned int num_elem = *num_elem_p;
160 int err;
161 unsigned long flags = 0, flags1;
162
163 new_q = rxe_queue_init(q->rxe, &num_elem, elem_size);
164 if (!new_q)
165 return -ENOMEM;
166
167 err = do_mmap_info(new_q->rxe, outbuf, udata, new_q->buf,
168 new_q->buf_size, &new_q->ip);
169 if (err) {
170 vfree(new_q->buf);
171 kfree(new_q);
172 goto err1;
173 }
174
175 spin_lock_irqsave(consumer_lock, flags1);
176
177 if (producer_lock) {
178 spin_lock_irqsave(producer_lock, flags);
179 err = resize_finish(q, new_q, num_elem);
180 spin_unlock_irqrestore(producer_lock, flags);
181 } else {
182 err = resize_finish(q, new_q, num_elem);
183 }
184
185 spin_unlock_irqrestore(consumer_lock, flags1);
186
187 rxe_queue_cleanup(new_q); /* new/old dep on err */
188 if (err)
189 goto err1;
190
191 *num_elem_p = num_elem;
192 return 0;
193
194 err1:
195 return err;
196 }
197
rxe_queue_cleanup(struct rxe_queue * q)198 void rxe_queue_cleanup(struct rxe_queue *q)
199 {
200 if (q->ip)
201 kref_put(&q->ip->ref, rxe_mmap_release);
202 else
203 vfree(q->buf);
204
205 kfree(q);
206 }
207
