arm64: Implement custom mmap functions for dma mapping

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / mm / dma-mapping.c

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index a48f1da828f6dc733463b7f6f80f05d4b4a0d198..18b83177f4b63341e84e793bcc6ea11b3f5f5817 100644 (file)
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -216,9 +216,52 @@ static void __swiotlb_sync_sg_for_device(struct device *dev,
                               sg->length, dir);
 }
 
+/* vma->vm_page_prot must be set appropriately before calling this function */
+static int __dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
+                            void *cpu_addr, dma_addr_t dma_addr, size_t size)
+{
+       int ret = -ENXIO;
+       unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >>
+                                       PAGE_SHIFT;
+       unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
+       unsigned long pfn = dma_to_phys(dev, dma_addr) >> PAGE_SHIFT;
+       unsigned long off = vma->vm_pgoff;
+
+       if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
+               return ret;
+
+       if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) {
+               ret = remap_pfn_range(vma, vma->vm_start,
+                                     pfn + off,
+                                     vma->vm_end - vma->vm_start,
+                                     vma->vm_page_prot);
+       }
+
+       return ret;
+}
+
+static int __swiotlb_mmap_noncoherent(struct device *dev,
+               struct vm_area_struct *vma,
+               void *cpu_addr, dma_addr_t dma_addr, size_t size,
+               struct dma_attrs *attrs)
+{
+       vma->vm_page_prot = pgprot_dmacoherent(vma->vm_page_prot);
+       return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+
+static int __swiotlb_mmap_coherent(struct device *dev,
+               struct vm_area_struct *vma,
+               void *cpu_addr, dma_addr_t dma_addr, size_t size,
+               struct dma_attrs *attrs)
+{
+       /* Just use whatever page_prot attributes were specified */
+       return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+
 struct dma_map_ops noncoherent_swiotlb_dma_ops = {
        .alloc = __dma_alloc_noncoherent,
        .free = __dma_free_noncoherent,
+       .mmap = __swiotlb_mmap_noncoherent,
        .map_page = __swiotlb_map_page,
        .unmap_page = __swiotlb_unmap_page,
        .map_sg = __swiotlb_map_sg_attrs,
@@ -235,6 +278,7 @@ EXPORT_SYMBOL(noncoherent_swiotlb_dma_ops);
 struct dma_map_ops coherent_swiotlb_dma_ops = {
        .alloc = __dma_alloc_coherent,
        .free = __dma_free_coherent,
+       .mmap = __swiotlb_mmap_coherent,
        .map_page = swiotlb_map_page,
        .unmap_page = swiotlb_unmap_page,
        .map_sg = swiotlb_map_sg_attrs,
@@ -254,7 +298,7 @@ static int __init swiotlb_late_init(void)
 {
        size_t swiotlb_size = min(SZ_64M, MAX_ORDER_NR_PAGES << PAGE_SHIFT);
 
-       dma_ops = &coherent_swiotlb_dma_ops;
+       dma_ops = &noncoherent_swiotlb_dma_ops;
 
        return swiotlb_late_init_with_default_size(swiotlb_size);
 }