ARC: dma: Use struct page based page allocator helpers

vs. the ones which reutne void *, so that we can handle pages > 4GB
in subsequent patches

Also plug a potential page leak in case ioremap fails

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index 01eaf88..6cf1d92 100644 (file)
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -24,15 +24,20 @@
 static void *arc_dma_alloc(struct device *dev, size_t size,
                dma_addr_t *dma_handle, gfp_t gfp, struct dma_attrs *attrs)
 {
-       void *paddr, *kvaddr;
+       unsigned long order = get_order(size);
+       struct page *page;
+       phys_addr_t paddr;
+       void *kvaddr;
 
-       /* This is linear addr (0x8000_0000 based) */
-       paddr = alloc_pages_exact(size, gfp);
-       if (!paddr)
+       page = alloc_pages(gfp, order);
+       if (!page)
                return NULL;
 
-       /* This is bus address, platform dependent */
-       *dma_handle = (dma_addr_t)paddr;
+       /* This is linear addr (0x8000_0000 based) */
+       paddr = page_to_phys(page);
+
+       /* For now bus address is exactly same as paddr */
+       *dma_handle = paddr;
 
        /*
         * IOC relies on all data (even coherent DMA data) being in cache
@@ -51,8 +56,10 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
 
        /* This is kernel Virtual address (0x7000_0000 based) */
        kvaddr = ioremap_nocache((unsigned long)paddr, size);
-       if (kvaddr == NULL)
+       if (kvaddr == NULL) {
+               __free_pages(page, order);
                return NULL;
+       }
 
        /*
         * Evict any existing L1 and/or L2 lines for the backing page
@@ -72,11 +79,13 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
 static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
                dma_addr_t dma_handle, struct dma_attrs *attrs)
 {
+       struct page *page = virt_to_page(dma_handle);
+
        if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs) &&
            !(is_isa_arcv2() && ioc_exists))
                iounmap((void __force __iomem *)vaddr);
 
-       free_pages_exact((void *)dma_handle, size);
+       __free_pages(page, get_order(size));
 }
 
 /*