135 lines · c
1/*2 * SPDX-License-Identifier: MIT3 *4 * Copyright © 2016 Intel Corporation5 */6 7#include <linux/vmalloc.h>8#include "mock_dmabuf.h"9 10static struct sg_table *mock_map_dma_buf(struct dma_buf_attachment *attachment,11 enum dma_data_direction dir)12{13 struct mock_dmabuf *mock = to_mock(attachment->dmabuf);14 struct sg_table *st;15 struct scatterlist *sg;16 int i, err;17 18 st = kmalloc(sizeof(*st), GFP_KERNEL);19 if (!st)20 return ERR_PTR(-ENOMEM);21 22 err = sg_alloc_table(st, mock->npages, GFP_KERNEL);23 if (err)24 goto err_free;25 26 sg = st->sgl;27 for (i = 0; i < mock->npages; i++) {28 sg_set_page(sg, mock->pages[i], PAGE_SIZE, 0);29 sg = sg_next(sg);30 }31 32 err = dma_map_sgtable(attachment->dev, st, dir, 0);33 if (err)34 goto err_st;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_sgtable(attachment->dev, st, dir, 0);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 int mock_dmabuf_vmap(struct dma_buf *dma_buf, struct iosys_map *map)66{67 struct mock_dmabuf *mock = to_mock(dma_buf);68 void *vaddr;69 70 vaddr = vm_map_ram(mock->pages, mock->npages, 0);71 if (!vaddr)72 return -ENOMEM;73 iosys_map_set_vaddr(map, vaddr);74 75 return 0;76}77 78static void mock_dmabuf_vunmap(struct dma_buf *dma_buf, struct iosys_map *map)79{80 struct mock_dmabuf *mock = to_mock(dma_buf);81 82 vm_unmap_ram(map->vaddr, mock->npages);83}84 85static int mock_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)86{87 return -ENODEV;88}89 90static const struct dma_buf_ops mock_dmabuf_ops = {91 .map_dma_buf = mock_map_dma_buf,92 .unmap_dma_buf = mock_unmap_dma_buf,93 .release = mock_dmabuf_release,94 .mmap = mock_dmabuf_mmap,95 .vmap = mock_dmabuf_vmap,96 .vunmap = mock_dmabuf_vunmap,97};98 99static struct dma_buf *mock_dmabuf(int npages)100{101 struct mock_dmabuf *mock;102 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);103 struct dma_buf *dmabuf;104 int i;105 106 mock = kmalloc(sizeof(*mock) + npages * sizeof(struct page *),107 GFP_KERNEL);108 if (!mock)109 return ERR_PTR(-ENOMEM);110 111 mock->npages = npages;112 for (i = 0; i < npages; i++) {113 mock->pages[i] = alloc_page(GFP_KERNEL);114 if (!mock->pages[i])115 goto err;116 }117 118 exp_info.ops = &mock_dmabuf_ops;119 exp_info.size = npages * PAGE_SIZE;120 exp_info.flags = O_CLOEXEC;121 exp_info.priv = mock;122 123 dmabuf = dma_buf_export(&exp_info);124 if (IS_ERR(dmabuf))125 goto err;126 127 return dmabuf;128 129err:130 while (i--)131 put_page(mock->pages[i]);132 kfree(mock);133 return ERR_PTR(-ENOMEM);134}135