]>
git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - lib/dma-virt.c
4 * DMA operations that map to virtual addresses without flushing memory.
6 #include <linux/export.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/scatterlist.h>
11 static void *dma_virt_alloc(struct device
*dev
, size_t size
,
12 dma_addr_t
*dma_handle
, gfp_t gfp
,
17 ret
= (void *)__get_free_pages(gfp
, get_order(size
));
19 *dma_handle
= (uintptr_t)ret
;
23 static void dma_virt_free(struct device
*dev
, size_t size
,
24 void *cpu_addr
, dma_addr_t dma_addr
,
27 free_pages((unsigned long)cpu_addr
, get_order(size
));
30 static dma_addr_t
dma_virt_map_page(struct device
*dev
, struct page
*page
,
31 unsigned long offset
, size_t size
,
32 enum dma_data_direction dir
,
35 return (uintptr_t)(page_address(page
) + offset
);
38 static int dma_virt_map_sg(struct device
*dev
, struct scatterlist
*sgl
,
39 int nents
, enum dma_data_direction dir
,
43 struct scatterlist
*sg
;
45 for_each_sg(sgl
, sg
, nents
, i
) {
47 sg_dma_address(sg
) = (uintptr_t)sg_virt(sg
);
48 sg_dma_len(sg
) = sg
->length
;
54 static int dma_virt_mapping_error(struct device
*dev
, dma_addr_t dma_addr
)
59 static int dma_virt_supported(struct device
*dev
, u64 mask
)
64 const struct dma_map_ops dma_virt_ops
= {
65 .alloc
= dma_virt_alloc
,
66 .free
= dma_virt_free
,
67 .map_page
= dma_virt_map_page
,
68 .map_sg
= dma_virt_map_sg
,
69 .mapping_error
= dma_virt_mapping_error
,
70 .dma_supported
= dma_virt_supported
,
72 EXPORT_SYMBOL(dma_virt_ops
);