sh: split coherent pages

Split pages returned by dma_alloc_coherent() and make sure
we free them one by one.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/arch/sh/mm/consistent.c b/arch/sh/mm/consistent.c
index 9f8ea3a..edcd5fb 100644 (file)
--- a/arch/sh/mm/consistent.c
+++ b/arch/sh/mm/consistent.c
@@ -42,6 +42,8 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
                return NULL;
        }
 
+       split_page(pfn_to_page(virt_to_phys(ret) >> PAGE_SHIFT), order);
+
        *dma_handle = virt_to_phys(ret);
        return ret_nocache;
 }
@@ -51,10 +53,13 @@ void dma_free_coherent(struct device *dev, size_t size,
                         void *vaddr, dma_addr_t dma_handle)
 {
        int order = get_order(size);
+       unsigned long pfn = dma_handle >> PAGE_SHIFT;
+       int k;
 
        if (!dma_release_from_coherent(dev, order, vaddr)) {
                WARN_ON(irqs_disabled());       /* for portability */
-               free_pages((unsigned long)phys_to_virt(dma_handle), order);
+               for (k = 0; k < (1 << order); k++)
+                       __free_pages(pfn_to_page(pfn + k), 0);
                iounmap(vaddr);
        }
 }