blob: c30669f14ac0f2f386ba524aae4eaba5add06c03 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Scatter-Gather buffer
3 *
4 * Copyright (c) by Takashi Iwai <tiwai@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/slab.h>
23#include <linux/mm.h>
24#include <linux/vmalloc.h>
25#include <sound/memalloc.h>
26
27
28/* table entries are align to 32 */
29#define SGBUF_TBL_ALIGN 32
30#define sgbuf_align_table(tbl) ((((tbl) + SGBUF_TBL_ALIGN - 1) / SGBUF_TBL_ALIGN) * SGBUF_TBL_ALIGN)
31
32int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab)
33{
34 struct snd_sg_buf *sgbuf = dmab->private_data;
35 struct snd_dma_buffer tmpb;
36 int i;
37
38 if (! sgbuf)
39 return -EINVAL;
40
41 tmpb.dev.type = SNDRV_DMA_TYPE_DEV;
42 tmpb.dev.dev = sgbuf->dev;
43 for (i = 0; i < sgbuf->pages; i++) {
44 tmpb.area = sgbuf->table[i].buf;
45 tmpb.addr = sgbuf->table[i].addr;
46 tmpb.bytes = PAGE_SIZE;
47 snd_dma_free_pages(&tmpb);
48 }
49 if (dmab->area)
50 vunmap(dmab->area);
51 dmab->area = NULL;
52
53 kfree(sgbuf->table);
54 kfree(sgbuf->page_table);
55 kfree(sgbuf);
56 dmab->private_data = NULL;
57
58 return 0;
59}
60
61void *snd_malloc_sgbuf_pages(struct device *device,
62 size_t size, struct snd_dma_buffer *dmab,
63 size_t *res_size)
64{
65 struct snd_sg_buf *sgbuf;
66 unsigned int i, pages;
67 struct snd_dma_buffer tmpb;
68
69 dmab->area = NULL;
70 dmab->addr = 0;
Panagiotis Issaris59feddb2006-07-25 15:28:03 +020071 dmab->private_data = sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 if (! sgbuf)
73 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 sgbuf->dev = device;
75 pages = snd_sgbuf_aligned_pages(size);
76 sgbuf->tblsize = sgbuf_align_table(pages);
Panagiotis Issaris59feddb2006-07-25 15:28:03 +020077 sgbuf->table = kcalloc(sgbuf->tblsize, sizeof(*sgbuf->table), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 if (! sgbuf->table)
79 goto _failed;
Panagiotis Issaris59feddb2006-07-25 15:28:03 +020080 sgbuf->page_table = kcalloc(sgbuf->tblsize, sizeof(*sgbuf->page_table), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 if (! sgbuf->page_table)
82 goto _failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84 /* allocate each page */
85 for (i = 0; i < pages; i++) {
86 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, device, PAGE_SIZE, &tmpb) < 0) {
87 if (res_size == NULL)
88 goto _failed;
89 *res_size = size = sgbuf->pages * PAGE_SIZE;
90 break;
91 }
92 sgbuf->table[i].buf = tmpb.area;
93 sgbuf->table[i].addr = tmpb.addr;
94 sgbuf->page_table[i] = virt_to_page(tmpb.area);
95 sgbuf->pages++;
96 }
97
98 sgbuf->size = size;
99 dmab->area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, PAGE_KERNEL);
100 if (! dmab->area)
101 goto _failed;
102 return dmab->area;
103
104 _failed:
105 snd_free_sgbuf_pages(dmab); /* free the table */
106 return NULL;
107}