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iommu/dma: Refactor iommu_dma_alloc, part 2

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All the logic in iommu_dma_alloc that deals with page allocation from
the CMA or page allocators can be split into a self-contained helper,
and we can than map the result of that or the atomic pool allocation
with the iommu later.  This also allows reusing __iommu_dma_free to
tear down the allocations and MMU mappings when the IOMMU mapping
fails.

Based on a patch from Robin Murphy.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Christoph Hellwig 2019-05-20 09:29:42 +02:00 committed by Joerg Roedel
parent 9ad5d6eddc
commit ee1ef05d02
1 changed files with 35 additions and 30 deletions
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65
drivers/iommu/dma-iommu.c
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@ -972,35 +972,14 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr,
__iommu_dma_free(dev, size, cpu_addr);
}
static void *iommu_dma_alloc(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t gfp, unsigned long attrs)
static void *iommu_dma_alloc_pages(struct device *dev, size_t size,
struct page **pagep, gfp_t gfp, unsigned long attrs)
{
bool coherent = dev_is_dma_coherent(dev);
int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs);
size_t alloc_size = PAGE_ALIGN(size);
struct page *page = NULL;
void *cpu_addr;
gfp |= __GFP_ZERO;
if (gfpflags_allow_blocking(gfp) &&
!(attrs & DMA_ATTR_FORCE_CONTIGUOUS))
return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs);
if (!gfpflags_allow_blocking(gfp) && !coherent) {
cpu_addr = dma_alloc_from_pool(alloc_size, &page, gfp);
if (!cpu_addr)
return NULL;
*handle = __iommu_dma_map(dev, page_to_phys(page), size,
ioprot);
if (*handle == DMA_MAPPING_ERROR) {
dma_free_from_pool(cpu_addr, alloc_size);
return NULL;
}
return cpu_addr;
}
if (gfpflags_allow_blocking(gfp))
page = dma_alloc_from_contiguous(dev, alloc_size >> PAGE_SHIFT,
get_order(alloc_size),
@ -1010,33 +989,59 @@ static void *iommu_dma_alloc(struct device *dev, size_t size,
if (!page)
return NULL;
*handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot);
if (*handle == DMA_MAPPING_ERROR)
goto out_free_pages;
if (!coherent || PageHighMem(page)) {
pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs);
cpu_addr = dma_common_contiguous_remap(page, alloc_size,
VM_USERMAP, prot, __builtin_return_address(0));
if (!cpu_addr)
goto out_unmap;
goto out_free_pages;
if (!coherent)
arch_dma_prep_coherent(page, size);
} else {
cpu_addr = page_address(page);
}
*pagep = page;
memset(cpu_addr, 0, alloc_size);
return cpu_addr;
out_unmap:
__iommu_dma_unmap(dev, *handle, size);
out_free_pages:
if (!dma_release_from_contiguous(dev, page, alloc_size >> PAGE_SHIFT))
__free_pages(page, get_order(alloc_size));
return NULL;
}
static void *iommu_dma_alloc(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t gfp, unsigned long attrs)
{
bool coherent = dev_is_dma_coherent(dev);
int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs);
struct page *page = NULL;
void *cpu_addr;
gfp |= __GFP_ZERO;
if (gfpflags_allow_blocking(gfp) &&
!(attrs & DMA_ATTR_FORCE_CONTIGUOUS))
return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs);
if (!gfpflags_allow_blocking(gfp) && !coherent)
cpu_addr = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp);
else
cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs);
if (!cpu_addr)
return NULL;
*handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot);
if (*handle == DMA_MAPPING_ERROR) {
__iommu_dma_free(dev, size, cpu_addr);
return NULL;
}
return cpu_addr;
}
static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma,
unsigned long pfn, size_t size)
{