Merge branch 'omap/multiplatform-fixes', tag 'v3.8-rc5' into next/multiplatform
[firefly-linux-kernel-4.4.55.git] / arch / arm / mm / dma-mapping.c
index 6b2fb87c8698a99254bdd56c0e4c2bf146994da5..076c26d43864f8a5b3da49ac7231a62e8edde0c2 100644 (file)
@@ -774,25 +774,27 @@ static void dma_cache_maint_page(struct page *page, unsigned long offset,
        size_t size, enum dma_data_direction dir,
        void (*op)(const void *, size_t, int))
 {
+       unsigned long pfn;
+       size_t left = size;
+
+       pfn = page_to_pfn(page) + offset / PAGE_SIZE;
+       offset %= PAGE_SIZE;
+
        /*
         * A single sg entry may refer to multiple physically contiguous
         * pages.  But we still need to process highmem pages individually.
         * If highmem is not configured then the bulk of this loop gets
         * optimized out.
         */
-       size_t left = size;
        do {
                size_t len = left;
                void *vaddr;
 
+               page = pfn_to_page(pfn);
+
                if (PageHighMem(page)) {
-                       if (len + offset > PAGE_SIZE) {
-                               if (offset >= PAGE_SIZE) {
-                                       page += offset / PAGE_SIZE;
-                                       offset %= PAGE_SIZE;
-                               }
+                       if (len + offset > PAGE_SIZE)
                                len = PAGE_SIZE - offset;
-                       }
                        vaddr = kmap_high_get(page);
                        if (vaddr) {
                                vaddr += offset;
@@ -809,7 +811,7 @@ static void dma_cache_maint_page(struct page *page, unsigned long offset,
                        op(vaddr, len, dir);
                }
                offset = 0;
-               page++;
+               pfn++;
                left -= len;
        } while (left);
 }