108 lines
2.9 KiB
C
108 lines
2.9 KiB
C
/*
|
|
* Scatter-Gather buffer
|
|
*
|
|
* Copyright (c) by Takashi Iwai <tiwai@suse.de>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*
|
|
*/
|
|
|
|
#include <linux/slab.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <sound/memalloc.h>
|
|
|
|
|
|
/* table entries are align to 32 */
|
|
#define SGBUF_TBL_ALIGN 32
|
|
#define sgbuf_align_table(tbl) ALIGN((tbl), SGBUF_TBL_ALIGN)
|
|
|
|
int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab)
|
|
{
|
|
struct snd_sg_buf *sgbuf = dmab->private_data;
|
|
struct snd_dma_buffer tmpb;
|
|
int i;
|
|
|
|
if (! sgbuf)
|
|
return -EINVAL;
|
|
|
|
tmpb.dev.type = SNDRV_DMA_TYPE_DEV;
|
|
tmpb.dev.dev = sgbuf->dev;
|
|
for (i = 0; i < sgbuf->pages; i++) {
|
|
tmpb.area = sgbuf->table[i].buf;
|
|
tmpb.addr = sgbuf->table[i].addr;
|
|
tmpb.bytes = PAGE_SIZE;
|
|
snd_dma_free_pages(&tmpb);
|
|
}
|
|
if (dmab->area)
|
|
vunmap(dmab->area);
|
|
dmab->area = NULL;
|
|
|
|
kfree(sgbuf->table);
|
|
kfree(sgbuf->page_table);
|
|
kfree(sgbuf);
|
|
dmab->private_data = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void *snd_malloc_sgbuf_pages(struct device *device,
|
|
size_t size, struct snd_dma_buffer *dmab,
|
|
size_t *res_size)
|
|
{
|
|
struct snd_sg_buf *sgbuf;
|
|
unsigned int i, pages;
|
|
struct snd_dma_buffer tmpb;
|
|
|
|
dmab->area = NULL;
|
|
dmab->addr = 0;
|
|
dmab->private_data = sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
|
|
if (! sgbuf)
|
|
return NULL;
|
|
sgbuf->dev = device;
|
|
pages = snd_sgbuf_aligned_pages(size);
|
|
sgbuf->tblsize = sgbuf_align_table(pages);
|
|
sgbuf->table = kcalloc(sgbuf->tblsize, sizeof(*sgbuf->table), GFP_KERNEL);
|
|
if (! sgbuf->table)
|
|
goto _failed;
|
|
sgbuf->page_table = kcalloc(sgbuf->tblsize, sizeof(*sgbuf->page_table), GFP_KERNEL);
|
|
if (! sgbuf->page_table)
|
|
goto _failed;
|
|
|
|
/* allocate each page */
|
|
for (i = 0; i < pages; i++) {
|
|
if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, device, PAGE_SIZE, &tmpb) < 0) {
|
|
if (res_size == NULL)
|
|
goto _failed;
|
|
*res_size = size = sgbuf->pages * PAGE_SIZE;
|
|
break;
|
|
}
|
|
sgbuf->table[i].buf = tmpb.area;
|
|
sgbuf->table[i].addr = tmpb.addr;
|
|
sgbuf->page_table[i] = virt_to_page(tmpb.area);
|
|
sgbuf->pages++;
|
|
}
|
|
|
|
sgbuf->size = size;
|
|
dmab->area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, PAGE_KERNEL);
|
|
if (! dmab->area)
|
|
goto _failed;
|
|
return dmab->area;
|
|
|
|
_failed:
|
|
snd_free_sgbuf_pages(dmab); /* free the table */
|
|
return NULL;
|
|
}
|