1 /*
2 * SPDX-License-Identifier: MIT
3 *
4 * Copyright © 2016 Intel Corporation
5 */
6
7 #include "mock_dmabuf.h"
8
mock_map_dma_buf(struct dma_buf_attachment * attachment,enum dma_data_direction dir)9 static 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 err = dma_map_sgtable(attachment->dev, st, dir, 0);
32 if (err)
33 goto err_st;
34
35 return st;
36
37 err_st:
38 sg_free_table(st);
39 err_free:
40 kfree(st);
41 return ERR_PTR(err);
42 }
43
mock_unmap_dma_buf(struct dma_buf_attachment * attachment,struct sg_table * st,enum dma_data_direction dir)44 static void mock_unmap_dma_buf(struct dma_buf_attachment *attachment,
45 struct sg_table *st,
46 enum dma_data_direction dir)
47 {
48 dma_unmap_sgtable(attachment->dev, st, dir, 0);
49 sg_free_table(st);
50 kfree(st);
51 }
52
mock_dmabuf_release(struct dma_buf * dma_buf)53 static void mock_dmabuf_release(struct dma_buf *dma_buf)
54 {
55 struct mock_dmabuf *mock = to_mock(dma_buf);
56 int i;
57
58 for (i = 0; i < mock->npages; i++)
59 put_page(mock->pages[i]);
60
61 kfree(mock);
62 }
63
mock_dmabuf_vmap(struct dma_buf * dma_buf)64 static void *mock_dmabuf_vmap(struct dma_buf *dma_buf)
65 {
66 struct mock_dmabuf *mock = to_mock(dma_buf);
67
68 return vm_map_ram(mock->pages, mock->npages, 0);
69 }
70
mock_dmabuf_vunmap(struct dma_buf * dma_buf,void * vaddr)71 static void mock_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
72 {
73 struct mock_dmabuf *mock = to_mock(dma_buf);
74
75 vm_unmap_ram(vaddr, mock->npages);
76 }
77
mock_dmabuf_mmap(struct dma_buf * dma_buf,struct vm_area_struct * vma)78 static int mock_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
79 {
80 return -ENODEV;
81 }
82
83 static const struct dma_buf_ops mock_dmabuf_ops = {
84 .map_dma_buf = mock_map_dma_buf,
85 .unmap_dma_buf = mock_unmap_dma_buf,
86 .release = mock_dmabuf_release,
87 .mmap = mock_dmabuf_mmap,
88 .vmap = mock_dmabuf_vmap,
89 .vunmap = mock_dmabuf_vunmap,
90 };
91
mock_dmabuf(int npages)92 static struct dma_buf *mock_dmabuf(int npages)
93 {
94 struct mock_dmabuf *mock;
95 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
96 struct dma_buf *dmabuf;
97 int i;
98
99 mock = kmalloc(sizeof(*mock) + npages * sizeof(struct page *),
100 GFP_KERNEL);
101 if (!mock)
102 return ERR_PTR(-ENOMEM);
103
104 mock->npages = npages;
105 for (i = 0; i < npages; i++) {
106 mock->pages[i] = alloc_page(GFP_KERNEL);
107 if (!mock->pages[i])
108 goto err;
109 }
110
111 exp_info.ops = &mock_dmabuf_ops;
112 exp_info.size = npages * PAGE_SIZE;
113 exp_info.flags = O_CLOEXEC;
114 exp_info.priv = mock;
115
116 dmabuf = dma_buf_export(&exp_info);
117 if (IS_ERR(dmabuf))
118 goto err;
119
120 return dmabuf;
121
122 err:
123 while (i--)
124 put_page(mock->pages[i]);
125 kfree(mock);
126 return ERR_PTR(-ENOMEM);
127 }
128
