Merge branch 'for-v3.11' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping

[~andy/linux] / arch / arm / mm / dma-mapping.c

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 7ec02961dfa0d8fe161d61071020fead4f89b7fc..7f9b1798c6cf12f08e55496b27082722e16a30f3 100644 (file)
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1328,6 +1328,15 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
        if (gfp & GFP_ATOMIC)
                return __iommu_alloc_atomic(dev, size, handle);
 
+       /*
+        * Following is a work-around (a.k.a. hack) to prevent pages
+        * with __GFP_COMP being passed to split_page() which cannot
+        * handle them.  The real problem is that this flag probably
+        * should be 0 on ARM as it is not supported on this
+        * platform; see CONFIG_HUGETLBFS.
+        */
+       gfp &= ~(__GFP_COMP);
+
        pages = __iommu_alloc_buffer(dev, size, gfp, attrs);
        if (!pages)
                return NULL;
@@ -1386,16 +1395,17 @@ static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
                          dma_addr_t handle, struct dma_attrs *attrs)
 {
-       struct page **pages = __iommu_get_pages(cpu_addr, attrs);
+       struct page **pages;
        size = PAGE_ALIGN(size);
 
-       if (!pages) {
-               WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
+       if (__in_atomic_pool(cpu_addr, size)) {
+               __iommu_free_atomic(dev, cpu_addr, handle, size);
                return;
        }
 
-       if (__in_atomic_pool(cpu_addr, size)) {
-               __iommu_free_atomic(dev, cpu_addr, handle, size);
+       pages = __iommu_get_pages(cpu_addr, attrs);
+       if (!pages) {
+               WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
                return;
        }
 
@@ -1650,13 +1660,27 @@ static dma_addr_t arm_coherent_iommu_map_page(struct device *dev, struct page *p
 {
        struct dma_iommu_mapping *mapping = dev->archdata.mapping;
        dma_addr_t dma_addr;
-       int ret, len = PAGE_ALIGN(size + offset);
+       int ret, prot, len = PAGE_ALIGN(size + offset);
 
        dma_addr = __alloc_iova(mapping, len);
        if (dma_addr == DMA_ERROR_CODE)
                return dma_addr;
 
-       ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, 0);
+       switch (dir) {
+       case DMA_BIDIRECTIONAL:
+               prot = IOMMU_READ | IOMMU_WRITE;
+               break;
+       case DMA_TO_DEVICE:
+               prot = IOMMU_READ;
+               break;
+       case DMA_FROM_DEVICE:
+               prot = IOMMU_WRITE;
+               break;
+       default:
+               prot = 0;
+       }
+
+       ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, prot);
        if (ret < 0)
                goto fail;
 
@@ -1921,7 +1945,7 @@ void arm_iommu_detach_device(struct device *dev)
 
        iommu_detach_device(mapping->domain, dev);
        kref_put(&mapping->kref, release_iommu_mapping);
-       mapping = NULL;
+       dev->archdata.mapping = NULL;
        set_dma_ops(dev, NULL);
 
        pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));