root/drivers/gpu/drm/i915/gem/selftests/mock_dmabuf.c

DEFINITIONS

1. mock_map_dma_buf
2. mock_unmap_dma_buf
3. mock_dmabuf_release
4. mock_dmabuf_vmap
5. mock_dmabuf_vunmap
6. mock_dmabuf_kmap
7. mock_dmabuf_kunmap
8. mock_dmabuf_mmap
9. mock_dmabuf

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright © 2016 Intel Corporation
   5  */
   6 
   7 #include "mock_dmabuf.h"
   8 
   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         if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
  32                 err = -ENOMEM;
  33                 goto err_st;
  34         }
  35 
  36         return st;
  37 
  38 err_st:
  39         sg_free_table(st);
  40 err_free:
  41         kfree(st);
  42         return ERR_PTR(err);
  43 }
  44 
  45 static 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 
  54 static 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 
  65 static 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 
  72 static 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 
  79 static 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 
  86 static 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 
  93 static int mock_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
  94 {
  95         return -ENODEV;
  96 }
  97 
  98 static 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 
 109 static 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 
 139 err:
 140         while (i--)
 141                 put_page(mock->pages[i]);
 142         kfree(mock);
 143         return ERR_PTR(-ENOMEM);
 144 }