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7#include "mock_dmabuf.h"
8
9static struct sg_table *mock_map_dma_buf(struct dma_buf_attachment *attachment,
10 enum dma_data_direction dir)
11{
12 struct mock_dmabuf *mock = to_mock(attachment->dmabuf);
13 struct sg_table *st;
14 struct scatterlist *sg;
15 int i, err;
16
17 st = kmalloc(sizeof(*st), GFP_KERNEL);
18 if (!st)
19 return ERR_PTR(-ENOMEM);
20
21 err = sg_alloc_table(st, mock->npages, GFP_KERNEL);
22 if (err)
23 goto err_free;
24
25 sg = st->sgl;
26 for (i = 0; i < mock->npages; i++) {
27 sg_set_page(sg, mock->pages[i], PAGE_SIZE, 0);
28 sg = sg_next(sg);
29 }
30
31 if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
32 err = -ENOMEM;
33 goto err_st;
34 }
35
36 return st;
37
38err_st:
39 sg_free_table(st);
40err_free:
41 kfree(st);
42 return ERR_PTR(err);
43}
44
45static void mock_unmap_dma_buf(struct dma_buf_attachment *attachment,
46 struct sg_table *st,
47 enum dma_data_direction dir)
48{
49 dma_unmap_sg(attachment->dev, st->sgl, st->nents, dir);
50 sg_free_table(st);
51 kfree(st);
52}
53
54static void mock_dmabuf_release(struct dma_buf *dma_buf)
55{
56 struct mock_dmabuf *mock = to_mock(dma_buf);
57 int i;
58
59 for (i = 0; i < mock->npages; i++)
60 put_page(mock->pages[i]);
61
62 kfree(mock);
63}
64
65static void *mock_dmabuf_vmap(struct dma_buf *dma_buf)
66{
67 struct mock_dmabuf *mock = to_mock(dma_buf);
68
69 return vm_map_ram(mock->pages, mock->npages, 0, PAGE_KERNEL);
70}
71
72static void mock_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
73{
74 struct mock_dmabuf *mock = to_mock(dma_buf);
75
76 vm_unmap_ram(vaddr, mock->npages);
77}
78
79static void *mock_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
80{
81 struct mock_dmabuf *mock = to_mock(dma_buf);
82
83 return kmap(mock->pages[page_num]);
84}
85
86static void mock_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
87{
88 struct mock_dmabuf *mock = to_mock(dma_buf);
89
90 return kunmap(mock->pages[page_num]);
91}
92
93static int mock_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
94{
95 return -ENODEV;
96}
97
98static const struct dma_buf_ops mock_dmabuf_ops = {
99 .map_dma_buf = mock_map_dma_buf,
100 .unmap_dma_buf = mock_unmap_dma_buf,
101 .release = mock_dmabuf_release,
102 .map = mock_dmabuf_kmap,
103 .unmap = mock_dmabuf_kunmap,
104 .mmap = mock_dmabuf_mmap,
105 .vmap = mock_dmabuf_vmap,
106 .vunmap = mock_dmabuf_vunmap,
107};
108
109static struct dma_buf *mock_dmabuf(int npages)
110{
111 struct mock_dmabuf *mock;
112 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
113 struct dma_buf *dmabuf;
114 int i;
115
116 mock = kmalloc(sizeof(*mock) + npages * sizeof(struct page *),
117 GFP_KERNEL);
118 if (!mock)
119 return ERR_PTR(-ENOMEM);
120
121 mock->npages = npages;
122 for (i = 0; i < npages; i++) {
123 mock->pages[i] = alloc_page(GFP_KERNEL);
124 if (!mock->pages[i])
125 goto err;
126 }
127
128 exp_info.ops = &mock_dmabuf_ops;
129 exp_info.size = npages * PAGE_SIZE;
130 exp_info.flags = O_CLOEXEC;
131 exp_info.priv = mock;
132
133 dmabuf = dma_buf_export(&exp_info);
134 if (IS_ERR(dmabuf))
135 goto err;
136
137 return dmabuf;
138
139err:
140 while (i--)
141 put_page(mock->pages[i]);
142 kfree(mock);
143 return ERR_PTR(-ENOMEM);
144}
145
