mirror of
https://github.com/torvalds/linux.git
synced 2024-11-21 19:46:16 +00:00
f69e342eec
Almost all instances of the dma_map_ops ->map_page()/map_sg() methods implement ->unmap_page()/unmap_sg() too. The once instance which doesn't dma_dummy_ops which is used to fail the DMA mapping and thus there won't be any calls to ->unmap_page()/unmap_sg(). Remove the checks for ->unmap_page()/unmap_sg() and call them directly to create an interface that is symmetrical to ->map_page()/map_sg(). Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
60 lines
1.5 KiB
C
60 lines
1.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Dummy DMA ops that always fail.
|
|
*/
|
|
#include <linux/dma-map-ops.h>
|
|
|
|
static int dma_dummy_mmap(struct device *dev, struct vm_area_struct *vma,
|
|
void *cpu_addr, dma_addr_t dma_addr, size_t size,
|
|
unsigned long attrs)
|
|
{
|
|
return -ENXIO;
|
|
}
|
|
|
|
static dma_addr_t dma_dummy_map_page(struct device *dev, struct page *page,
|
|
unsigned long offset, size_t size, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
return DMA_MAPPING_ERROR;
|
|
}
|
|
static void dma_dummy_unmap_page(struct device *dev, dma_addr_t dma_handle,
|
|
size_t size, enum dma_data_direction dir, unsigned long attrs)
|
|
{
|
|
/*
|
|
* Dummy ops doesn't support map_page, so unmap_page should never be
|
|
* called.
|
|
*/
|
|
WARN_ON_ONCE(true);
|
|
}
|
|
|
|
static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
|
|
int nelems, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static void dma_dummy_unmap_sg(struct device *dev, struct scatterlist *sgl,
|
|
int nelems, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
/*
|
|
* Dummy ops doesn't support map_sg, so unmap_sg should never be called.
|
|
*/
|
|
WARN_ON_ONCE(true);
|
|
}
|
|
|
|
static int dma_dummy_supported(struct device *hwdev, u64 mask)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
const struct dma_map_ops dma_dummy_ops = {
|
|
.mmap = dma_dummy_mmap,
|
|
.map_page = dma_dummy_map_page,
|
|
.unmap_page = dma_dummy_unmap_page,
|
|
.map_sg = dma_dummy_map_sg,
|
|
.unmap_sg = dma_dummy_unmap_sg,
|
|
.dma_supported = dma_dummy_supported,
|
|
};
|