ARM: dma-mapping: Introduce __atomic_get_pages() for __iommu_get_pages()
Hiroshi Doyu [Thu, 23 Aug 2012 12:24:06 +0000 (15:24 +0300)]
Support atomic allocation in __iommu_get_pages().

Change-Id: I16f94a0ad9a54ffc53bac4e53c090336c4b5560d
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>

arch/arm/mm/dma-mapping.c

index a734438..1b964a0 100644 (file)
@@ -503,6 +503,15 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page)
        return ptr;
 }
 
+static struct page **__atomic_get_pages(void *addr)
+{
+       struct dma_pool *pool = &atomic_pool;
+       struct page **pages = pool->pages;
+       int offs = (addr - pool->vaddr) >> PAGE_SHIFT;
+
+       return pages + offs;
+}
+
 static bool __in_atomic_pool(void *start, size_t size)
 {
        struct dma_pool *pool = &atomic_pool;
@@ -1187,6 +1196,9 @@ static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
 {
        struct vm_struct *area;
 
+       if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
+               return __atomic_get_pages(cpu_addr);
+
        if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
                return cpu_addr;