1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /*
3 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
4 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
5 */
6
7 #include <linux/vmalloc.h>
8 #include "rxe.h"
9 #include "rxe_loc.h"
10 #include "rxe_queue.h"
11
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)12 int do_mmap_info(struct rxe_dev *rxe, struct mminfo __user *outbuf,
13 struct ib_udata *udata, struct rxe_queue_buf *buf,
14 size_t buf_size, struct rxe_mmap_info **ip_p)
15 {
16 int err;
17 struct rxe_mmap_info *ip = NULL;
18
19 if (outbuf) {
20 ip = rxe_create_mmap_info(rxe, buf_size, udata, buf);
21 if (IS_ERR(ip)) {
22 err = PTR_ERR(ip);
23 goto err1;
24 }
25
26 if (copy_to_user(outbuf, &ip->info, sizeof(ip->info))) {
27 err = -EFAULT;
28 goto err2;
29 }
30
31 spin_lock_bh(&rxe->pending_lock);
32 list_add(&ip->pending_mmaps, &rxe->pending_mmaps);
33 spin_unlock_bh(&rxe->pending_lock);
34 }
35
36 *ip_p = ip;
37
38 return 0;
39
40 err2:
41 kfree(ip);
42 err1:
43 return err;
44 }
45
rxe_queue_reset(struct rxe_queue * q)46 inline void rxe_queue_reset(struct rxe_queue *q)
47 {
48 /* queue is comprised from header and the memory
49 * of the actual queue. See "struct rxe_queue_buf" in rxe_queue.h
50 * reset only the queue itself and not the management header
51 */
52 memset(q->buf->data, 0, q->buf_size - sizeof(struct rxe_queue_buf));
53 }
54
rxe_queue_init(struct rxe_dev * rxe,int * num_elem,unsigned int elem_size,enum queue_type type)55 struct rxe_queue *rxe_queue_init(struct rxe_dev *rxe, int *num_elem,
56 unsigned int elem_size, enum queue_type type)
57 {
58 struct rxe_queue *q;
59 size_t buf_size;
60 unsigned int num_slots;
61
62 /* num_elem == 0 is allowed, but uninteresting */
63 if (*num_elem < 0)
64 goto err1;
65
66 q = kzalloc(sizeof(*q), GFP_KERNEL);
67 if (!q)
68 goto err1;
69
70 q->rxe = rxe;
71 q->type = type;
72
73 /* used in resize, only need to copy used part of queue */
74 q->elem_size = elem_size;
75
76 /* pad element up to at least a cacheline and always a power of 2 */
77 if (elem_size < cache_line_size())
78 elem_size = cache_line_size();
79 elem_size = roundup_pow_of_two(elem_size);
80
81 q->log2_elem_size = order_base_2(elem_size);
82
83 num_slots = *num_elem + 1;
84 num_slots = roundup_pow_of_two(num_slots);
85 q->index_mask = num_slots - 1;
86
87 buf_size = sizeof(struct rxe_queue_buf) + num_slots * elem_size;
88
89 q->buf = vmalloc_user(buf_size);
90 if (!q->buf)
91 goto err2;
92
93 q->buf->log2_elem_size = q->log2_elem_size;
94 q->buf->index_mask = q->index_mask;
95
96 q->buf_size = buf_size;
97
98 *num_elem = num_slots - 1;
99 return q;
100
101 err2:
102 kfree(q);
103 err1:
104 return NULL;
105 }
106
107 /* copies elements from original q to new q and then swaps the contents of the
108 * two q headers. This is so that if anyone is holding a pointer to q it will
109 * still work
110 */
resize_finish(struct rxe_queue * q,struct rxe_queue * new_q,unsigned int num_elem)111 static int resize_finish(struct rxe_queue *q, struct rxe_queue *new_q,
112 unsigned int num_elem)
113 {
114 enum queue_type type = q->type;
115 u32 prod;
116 u32 cons;
117
118 if (!queue_empty(q, q->type) && (num_elem < queue_count(q, type)))
119 return -EINVAL;
120
121 prod = queue_get_producer(new_q, type);
122 cons = queue_get_consumer(q, type);
123
124 while (!queue_empty(q, type)) {
125 memcpy(queue_addr_from_index(new_q, prod),
126 queue_addr_from_index(q, cons), new_q->elem_size);
127 prod = queue_next_index(new_q, prod);
128 cons = queue_next_index(q, cons);
129 }
130
131 new_q->buf->producer_index = prod;
132 q->buf->consumer_index = cons;
133
134 /* update private index copies */
135 if (type == QUEUE_TYPE_TO_CLIENT)
136 new_q->index = new_q->buf->producer_index;
137 else
138 q->index = q->buf->consumer_index;
139
140 /* exchange rxe_queue headers */
141 swap(*q, *new_q);
142
143 return 0;
144 }
145
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)146 int rxe_queue_resize(struct rxe_queue *q, unsigned int *num_elem_p,
147 unsigned int elem_size, struct ib_udata *udata,
148 struct mminfo __user *outbuf, spinlock_t *producer_lock,
149 spinlock_t *consumer_lock)
150 {
151 struct rxe_queue *new_q;
152 unsigned int num_elem = *num_elem_p;
153 int err;
154 unsigned long flags = 0, flags1;
155
156 new_q = rxe_queue_init(q->rxe, &num_elem, elem_size, q->type);
157 if (!new_q)
158 return -ENOMEM;
159
160 err = do_mmap_info(new_q->rxe, outbuf, udata, new_q->buf,
161 new_q->buf_size, &new_q->ip);
162 if (err) {
163 vfree(new_q->buf);
164 kfree(new_q);
165 goto err1;
166 }
167
168 spin_lock_irqsave(consumer_lock, flags1);
169
170 if (producer_lock) {
171 spin_lock_irqsave(producer_lock, flags);
172 err = resize_finish(q, new_q, num_elem);
173 spin_unlock_irqrestore(producer_lock, flags);
174 } else {
175 err = resize_finish(q, new_q, num_elem);
176 }
177
178 spin_unlock_irqrestore(consumer_lock, flags1);
179
180 rxe_queue_cleanup(new_q); /* new/old dep on err */
181 if (err)
182 goto err1;
183
184 *num_elem_p = num_elem;
185 return 0;
186
187 err1:
188 return err;
189 }
190
rxe_queue_cleanup(struct rxe_queue * q)191 void rxe_queue_cleanup(struct rxe_queue *q)
192 {
193 if (q->ip)
194 kref_put(&q->ip->ref, rxe_mmap_release);
195 else
196 vfree(q->buf);
197
198 kfree(q);
199 }
200