blob: 74745da9deb69f4cf171500dc6523435c1839752 [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
22#include <linux/config.h>
23#include <linux/slab.h>
24#include <linux/mm.h>
25#include <linux/vmalloc.h>
26#include <sound/memalloc.h>
27
28
29/* table entries are align to 32 */
30#define SGBUF_TBL_ALIGN 32
31#define sgbuf_align_table(tbl) ((((tbl) + SGBUF_TBL_ALIGN - 1) / SGBUF_TBL_ALIGN) * SGBUF_TBL_ALIGN)
32
33int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab)
34{
35 struct snd_sg_buf *sgbuf = dmab->private_data;
36 struct snd_dma_buffer tmpb;
37 int i;
38
39 if (! sgbuf)
40 return -EINVAL;
41
42 tmpb.dev.type = SNDRV_DMA_TYPE_DEV;
43 tmpb.dev.dev = sgbuf->dev;
44 for (i = 0; i < sgbuf->pages; i++) {
45 tmpb.area = sgbuf->table[i].buf;
46 tmpb.addr = sgbuf->table[i].addr;
47 tmpb.bytes = PAGE_SIZE;
48 snd_dma_free_pages(&tmpb);
49 }
50 if (dmab->area)
51 vunmap(dmab->area);
52 dmab->area = NULL;
53
54 kfree(sgbuf->table);
55 kfree(sgbuf->page_table);
56 kfree(sgbuf);
57 dmab->private_data = NULL;
58
59 return 0;
60}
61
62void *snd_malloc_sgbuf_pages(struct device *device,
63 size_t size, struct snd_dma_buffer *dmab,
64 size_t *res_size)
65{
66 struct snd_sg_buf *sgbuf;
67 unsigned int i, pages;
68 struct snd_dma_buffer tmpb;
69
70 dmab->area = NULL;
71 dmab->addr = 0;
72 dmab->private_data = sgbuf = kmalloc(sizeof(*sgbuf), GFP_KERNEL);
73 if (! sgbuf)
74 return NULL;
75 memset(sgbuf, 0, sizeof(*sgbuf));
76 sgbuf->dev = device;
77 pages = snd_sgbuf_aligned_pages(size);
78 sgbuf->tblsize = sgbuf_align_table(pages);
79 sgbuf->table = kmalloc(sizeof(*sgbuf->table) * sgbuf->tblsize, GFP_KERNEL);
80 if (! sgbuf->table)
81 goto _failed;
82 memset(sgbuf->table, 0, sizeof(*sgbuf->table) * sgbuf->tblsize);
83 sgbuf->page_table = kmalloc(sizeof(*sgbuf->page_table) * sgbuf->tblsize, GFP_KERNEL);
84 if (! sgbuf->page_table)
85 goto _failed;
86 memset(sgbuf->page_table, 0, sizeof(*sgbuf->page_table) * sgbuf->tblsize);
87
88 /* allocate each page */
89 for (i = 0; i < pages; i++) {
90 if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, device, PAGE_SIZE, &tmpb) < 0) {
91 if (res_size == NULL)
92 goto _failed;
93 *res_size = size = sgbuf->pages * PAGE_SIZE;
94 break;
95 }
96 sgbuf->table[i].buf = tmpb.area;
97 sgbuf->table[i].addr = tmpb.addr;
98 sgbuf->page_table[i] = virt_to_page(tmpb.area);
99 sgbuf->pages++;
100 }
101
102 sgbuf->size = size;
103 dmab->area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, PAGE_KERNEL);
104 if (! dmab->area)
105 goto _failed;
106 return dmab->area;
107
108 _failed:
109 snd_free_sgbuf_pages(dmab); /* free the table */
110 return NULL;
111}