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
|
/* $OpenBSD: dma_alloc.c,v 1.1 2010/07/13 16:47:03 deraadt Exp $ */
/*
* Copyright (c) 2010 Theo de Raadt <deraadt@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/param.h>
#include <sys/pool.h>
#include <uvm/uvm.h>
static __inline int dma_alloc_index(size_t size);
#define DMA_BUCKET_OFFSET 4
static char dmanames[PAGE_SHIFT - DMA_BUCKET_OFFSET][8];
struct pool dmapools[PAGE_SHIFT - DMA_BUCKET_OFFSET];
void
dma_alloc_init(void)
{
int i;
for (i = 0; i < nitems(dmapools); i++) {
snprintf(dmanames[i], sizeof(dmanames[0]), "dma%d",
1 << (i + DMA_BUCKET_OFFSET));
pool_init(&dmapools[i], 1 << (i + DMA_BUCKET_OFFSET), 0, 0, 0,
dmanames[i], NULL);
pool_set_constraints(&dmapools[i], &dma_constraint, 1);
/* XXX need pool_setlowat(&dmapools[i], dmalowat); */
}
}
static __inline int
dma_alloc_index(size_t sz)
{
int b;
for (b = 0; b < nitems(dmapools); b++)
if (sz <= (1 << (b + DMA_BUCKET_OFFSET)))
return (b);
#ifdef DEBUG
printf("dma_alloc/free: object %d too large\n", sz)
#endif
return (-1);
}
void *
dma_alloc(size_t size, int prflags)
{
int pi = dma_alloc_index(size);
if (pi == -1)
return (NULL);
return pool_get(&dmapools[pi], prflags);
}
void
dma_free(void *m, size_t size)
{
int pi = dma_alloc_index(size);
if (pi == -1)
return;
pool_put(&dmapools[pi], m);
}
|
