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22#include <linux/slab.h>
23#include <linux/mm.h>
24#include <linux/vmalloc.h>
25#include <sound/memalloc.h>
26
27
28
29#define SGBUF_TBL_ALIGN 32
30#define sgbuf_align_table(tbl) ALIGN((tbl), 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;
71 dmab->private_data = sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
72 if (! sgbuf)
73 return NULL;
74 sgbuf->dev = device;
75 pages = snd_sgbuf_aligned_pages(size);
76 sgbuf->tblsize = sgbuf_align_table(pages);
77 sgbuf->table = kcalloc(sgbuf->tblsize, sizeof(*sgbuf->table), GFP_KERNEL);
78 if (! sgbuf->table)
79 goto _failed;
80 sgbuf->page_table = kcalloc(sgbuf->tblsize, sizeof(*sgbuf->page_table), GFP_KERNEL);
81 if (! sgbuf->page_table)
82 goto _failed;
83
84
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);
106 return NULL;
107}
108