Move the call to dma_common_pages_remap / dma_common_free_remap into __iommu_dma_alloc / __iommu_dma_free and rename those functions to better describe what they do. This keeps the functionality that allocates and remaps a non-contigous array of pages nicely abstracted out from the calling code.
Signed-off-by: Christoph Hellwig <h...@lst.de> --- drivers/iommu/dma-iommu.c | 73 ++++++++++++++++++--------------------- 1 file changed, 34 insertions(+), 39 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 0727c109bcab..95d30b96e5bd 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -526,51 +526,57 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev, } /** - * iommu_dma_free - Free a buffer allocated by __iommu_dma_alloc() + * iommu_dma_free_remap - Free a buffer allocated by iommu_dma_alloc_remap * @dev: Device which owns this buffer - * @pages: Array of buffer pages as returned by __iommu_dma_alloc() * @size: Size of buffer in bytes + * @cpu_address: Virtual address of the buffer * @handle: DMA address of buffer * * Frees both the pages associated with the buffer, and the array * describing them */ -static void __iommu_dma_free(struct device *dev, struct page **pages, - size_t size, dma_addr_t *handle) +static void iommu_dma_free_remap(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t dma_handle) { - __iommu_dma_unmap(iommu_get_dma_domain(dev), *handle, size); - __iommu_dma_free_pages(pages, PAGE_ALIGN(size) >> PAGE_SHIFT); - *handle = DMA_MAPPING_ERROR; + struct vm_struct *area = find_vm_area(cpu_addr); + + if (WARN_ON(!area || !area->pages)) + return; + __iommu_dma_unmap(iommu_get_dma_domain(dev), dma_handle, size); + __iommu_dma_free_pages(area->pages, PAGE_ALIGN(size) >> PAGE_SHIFT); + dma_common_free_remap(cpu_addr, PAGE_ALIGN(size), VM_USERMAP); } /** - * __iommu_dma_alloc - Allocate and map a buffer contiguous in IOVA space + * iommu_dma_alloc_remap - Allocate and map a buffer contiguous in IOVA space * @dev: Device to allocate memory for. Must be a real device * attached to an iommu_dma_domain * @size: Size of buffer in bytes + * @dma_handle: Out argument for allocated DMA handle * @gfp: Allocation flags * @attrs: DMA attributes for this allocation - * @prot: IOMMU mapping flags - * @handle: Out argument for allocated DMA handle * * If @size is less than PAGE_SIZE, then a full CPU page will be allocated, * but an IOMMU which supports smaller pages might not map the whole thing. * - * Return: Array of struct page pointers describing the buffer, - * or NULL on failure. + * Return: Mapped virtual address, or NULL on failure. */ -static struct page **__iommu_dma_alloc(struct device *dev, size_t size, - gfp_t gfp, unsigned long attrs, int prot, dma_addr_t *handle) +static void *iommu_dma_alloc_remap(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iova_domain *iovad = &cookie->iovad; + bool coherent = dev_is_dma_coherent(dev); + int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); + pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); + unsigned int count, min_size, alloc_sizes = domain->pgsize_bitmap, i; struct page **pages; dma_addr_t iova; - unsigned int count, min_size, alloc_sizes = domain->pgsize_bitmap, i; size_t mapped = 0; + void *vaddr; - *handle = DMA_MAPPING_ERROR; + *dma_handle = DMA_MAPPING_ERROR; min_size = alloc_sizes & -alloc_sizes; if (min_size < PAGE_SIZE) { @@ -596,16 +602,21 @@ static struct page **__iommu_dma_alloc(struct device *dev, size_t size, for (i = 0; i < count; i++) { phys_addr_t phys = page_to_phys(pages[i]); - if (!(prot & IOMMU_CACHE)) + if (!(ioprot & IOMMU_CACHE)) arch_dma_prep_coherent(pages[i], PAGE_SIZE); - if (iommu_map(domain, iova + mapped, phys, PAGE_SIZE, prot)) + if (iommu_map(domain, iova + mapped, phys, PAGE_SIZE, ioprot)) goto out_unmap; mapped += PAGE_SIZE; } - *handle = iova; - return pages; + vaddr = dma_common_pages_remap(pages, size, VM_USERMAP, prot, + __builtin_return_address(0)); + if (!vaddr) + goto out_unmap; + + *dma_handle = iova; + return vaddr; out_unmap: iommu_unmap(domain, iova, mapped); iommu_dma_free_iova(cookie, iova, size); @@ -1008,18 +1019,7 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, size >> PAGE_SHIFT); } } else { - pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); - struct page **pages; - - pages = __iommu_dma_alloc(dev, iosize, gfp, attrs, ioprot, - handle); - if (!pages) - return NULL; - - addr = dma_common_pages_remap(pages, size, VM_USERMAP, prot, - __builtin_return_address(0)); - if (!addr) - __iommu_dma_free(dev, pages, iosize, handle); + addr = iommu_dma_alloc_remap(dev, iosize, handle, gfp, attrs); } return addr; } @@ -1033,7 +1033,7 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, /* * @cpu_addr will be one of 4 things depending on how it was allocated: * - A remapped array of pages for contiguous allocations. - * - A remapped array of pages from __iommu_dma_alloc(), for all + * - A remapped array of pages from iommu_dma_alloc_remap(), for all * non-atomic allocations. * - A non-cacheable alias from the atomic pool, for atomic * allocations by non-coherent devices. @@ -1051,12 +1051,7 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT); dma_common_free_remap(cpu_addr, size, VM_USERMAP); } else if (is_vmalloc_addr(cpu_addr)){ - struct vm_struct *area = find_vm_area(cpu_addr); - - if (WARN_ON(!area || !area->pages)) - return; - __iommu_dma_free(dev, area->pages, iosize, &handle); - dma_common_free_remap(cpu_addr, size, VM_USERMAP); + iommu_dma_free_remap(dev, iosize, cpu_addr, handle); } else { __iommu_dma_unmap_page(dev, handle, iosize, 0, 0); __free_pages(virt_to_page(cpu_addr), get_order(size)); -- 2.20.1