1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/*
* Copyright (c) 2007 Cisco Systems, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/slab.h>
#include "mlx4_ib.h"
struct mlx4_ib_db_pgdir {
struct list_head list;
DECLARE_BITMAP(order0, MLX4_IB_DB_PER_PAGE);
DECLARE_BITMAP(order1, MLX4_IB_DB_PER_PAGE / 2);
unsigned long *bits[2];
__be32 *db_page;
dma_addr_t db_dma;
};
static struct mlx4_ib_db_pgdir *mlx4_ib_alloc_db_pgdir(struct mlx4_ib_dev *dev)
{
struct mlx4_ib_db_pgdir *pgdir;
pgdir = kzalloc(sizeof *pgdir, GFP_KERNEL);
if (!pgdir)
return NULL;
bitmap_fill(pgdir->order1, MLX4_IB_DB_PER_PAGE / 2);
pgdir->bits[0] = pgdir->order0;
pgdir->bits[1] = pgdir->order1;
pgdir->db_page = dma_alloc_coherent(dev->ib_dev.dma_device,
PAGE_SIZE, &pgdir->db_dma,
GFP_KERNEL);
if (!pgdir->db_page) {
kfree(pgdir);
return NULL;
}
return pgdir;
}
static int mlx4_ib_alloc_db_from_pgdir(struct mlx4_ib_db_pgdir *pgdir,
struct mlx4_ib_db *db, int order)
{
int o;
int i;
for (o = order; o <= 1; ++o) {
i = find_first_bit(pgdir->bits[o], MLX4_IB_DB_PER_PAGE >> o);
if (i < MLX4_IB_DB_PER_PAGE >> o)
goto found;
}
return -ENOMEM;
found:
clear_bit(i, pgdir->bits[o]);
i <<= o;
if (o > order)
set_bit(i ^ 1, pgdir->bits[order]);
db->u.pgdir = pgdir;
db->index = i;
db->db = pgdir->db_page + db->index;
db->dma = pgdir->db_dma + db->index * 4;
db->order = order;
return 0;
}
int mlx4_ib_db_alloc(struct mlx4_ib_dev *dev, struct mlx4_ib_db *db, int order)
{
struct mlx4_ib_db_pgdir *pgdir;
int ret = 0;
mutex_lock(&dev->pgdir_mutex);
list_for_each_entry(pgdir, &dev->pgdir_list, list)
if (!mlx4_ib_alloc_db_from_pgdir(pgdir, db, order))
goto out;
pgdir = mlx4_ib_alloc_db_pgdir(dev);
if (!pgdir) {
ret = -ENOMEM;
goto out;
}
list_add(&pgdir->list, &dev->pgdir_list);
/* This should never fail -- we just allocated an empty page: */
WARN_ON(mlx4_ib_alloc_db_from_pgdir(pgdir, db, order));
out:
mutex_unlock(&dev->pgdir_mutex);
return ret;
}
void mlx4_ib_db_free(struct mlx4_ib_dev *dev, struct mlx4_ib_db *db)
{
int o;
int i;
mutex_lock(&dev->pgdir_mutex);
o = db->order;
i = db->index;
if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) {
clear_bit(i ^ 1, db->u.pgdir->order0);
++o;
}
i >>= o;
set_bit(i, db->u.pgdir->bits[o]);
if (bitmap_full(db->u.pgdir->order1, MLX4_IB_DB_PER_PAGE / 2)) {
dma_free_coherent(dev->ib_dev.dma_device, PAGE_SIZE,
db->u.pgdir->db_page, db->u.pgdir->db_dma);
list_del(&db->u.pgdir->list);
kfree(db->u.pgdir);
}
mutex_unlock(&dev->pgdir_mutex);
}
struct mlx4_ib_user_db_page {
struct list_head list;
struct ib_umem *umem;
unsigned long user_virt;
int refcnt;
};
int mlx4_ib_db_map_user(struct mlx4_ib_ucontext *context, unsigned long virt,
struct mlx4_ib_db *db)
{
struct mlx4_ib_user_db_page *page;
struct ib_umem_chunk *chunk;
int err = 0;
mutex_lock(&context->db_page_mutex);
list_for_each_entry(page, &context->db_page_list, list)
if (page->user_virt == (virt & PAGE_MASK))
goto found;
page = kmalloc(sizeof *page, GFP_KERNEL);
if (!page) {
err = -ENOMEM;
goto out;
}
page->user_virt = (virt & PAGE_MASK);
page->refcnt = 0;
page->umem = ib_umem_get(&context->ibucontext, virt & PAGE_MASK,
PAGE_SIZE, 0);
if (IS_ERR(page->umem)) {
err = PTR_ERR(page->umem);
kfree(page);
goto out;
}
list_add(&page->list, &context->db_page_list);
found:
chunk = list_entry(page->umem->chunk_list.next, struct ib_umem_chunk, list);
db->dma = sg_dma_address(chunk->page_list) + (virt & ~PAGE_MASK);
db->u.user_page = page;
++page->refcnt;
out:
mutex_unlock(&context->db_page_mutex);
return err;
}
void mlx4_ib_db_unmap_user(struct mlx4_ib_ucontext *context, struct mlx4_ib_db *db)
{
mutex_lock(&context->db_page_mutex);
if (!--db->u.user_page->refcnt) {
list_del(&db->u.user_page->list);
ib_umem_release(db->u.user_page->umem);
kfree(db->u.user_page);
}
mutex_unlock(&context->db_page_mutex);
}
|
