82 lines
2.1 KiB
C
82 lines
2.1 KiB
C
|
/* $OpenBSD: dma_alloc.c,v 1.13 2016/09/15 02:00:16 dlg 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/systm.h>
|
||
|
#include <sys/pool.h>
|
||
|
|
||
|
#include <uvm/uvm_extern.h>
|
||
|
|
||
|
static __inline int dma_alloc_index(size_t size);
|
||
|
|
||
|
/* Create dma pools from objects sized 2^4 to 2^16 */
|
||
|
#define DMA_PAGE_SHIFT 16
|
||
|
#define DMA_BUCKET_OFFSET 4
|
||
|
static char dmanames[DMA_PAGE_SHIFT - DMA_BUCKET_OFFSET + 1][10];
|
||
|
struct pool dmapools[DMA_PAGE_SHIFT - DMA_BUCKET_OFFSET + 1];
|
||
|
|
||
|
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,
|
||
|
IPL_VM, 0, dmanames[i], NULL);
|
||
|
pool_set_constraints(&dmapools[i], &kp_dma_contig);
|
||
|
/* 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 %zd 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);
|
||
|
}
|