iommu/dma: Refactor iommu_dma_get_sgtable

Inline __iommu_dma_get_sgtable_page into the main function, and use the
fact that __iommu_dma_get_pages return NULL for remapped contigous
allocations to simplify the code flow a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Christoph Hellwig 2019-05-20 09:29:43 +02:00 committed by Joerg Roedel
parent ee1ef05d02
commit 3fb3378bb1

View file

@ -1097,42 +1097,31 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma,
return __iommu_dma_mmap(pages, size, vma);
}
static int __iommu_dma_get_sgtable_page(struct sg_table *sgt, struct page *page,
size_t size)
{
int ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
if (!ret)
sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
return ret;
}
static int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
unsigned long attrs)
{
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
struct page **pages;
struct page *page;
int ret;
if (!is_vmalloc_addr(cpu_addr)) {
struct page *page = virt_to_page(cpu_addr);
return __iommu_dma_get_sgtable_page(sgt, page, size);
if (is_vmalloc_addr(cpu_addr)) {
struct page **pages = __iommu_dma_get_pages(cpu_addr);
if (pages) {
return sg_alloc_table_from_pages(sgt, pages,
PAGE_ALIGN(size) >> PAGE_SHIFT,
0, size, GFP_KERNEL);
}
page = vmalloc_to_page(cpu_addr);
} else {
page = virt_to_page(cpu_addr);
}
if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {
/*
* DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped,
* hence in the vmalloc space.
*/
struct page *page = vmalloc_to_page(cpu_addr);
return __iommu_dma_get_sgtable_page(sgt, page, size);
}
pages = __iommu_dma_get_pages(cpu_addr);
if (!pages)
return -ENXIO;
return sg_alloc_table_from_pages(sgt, pages, count, 0, size,
GFP_KERNEL);
ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
if (!ret)
sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
return ret;
}
static const struct dma_map_ops iommu_dma_ops = {