dma-mapping: refactor dma_{alloc,free}_pages

Factour out internal versions without the dma_debug calls in preparation
for callers that will need different dma_debug calls.

Note that this changes the dma_debug calls to get the not page aligned
size values, but as long as alloc and free agree on one variant we are
fine.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 9ce86c77651c6f10819c7f3195a5121844c18bb0..07f964ebcda15e542f625be8631908b23963c7c2 100644 (file)
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -477,11 +477,10 @@ void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 }
 EXPORT_SYMBOL(dma_free_attrs);
 
-struct page *dma_alloc_pages(struct device *dev, size_t size,
+static struct page *__dma_alloc_pages(struct device *dev, size_t size,
                dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
 {
        const struct dma_map_ops *ops = get_dma_ops(dev);
-       struct page *page;
 
        if (WARN_ON_ONCE(!dev->coherent_dma_mask))
                return NULL;
@@ -490,31 +489,41 @@ struct page *dma_alloc_pages(struct device *dev, size_t size,
 
        size = PAGE_ALIGN(size);
        if (dma_alloc_direct(dev, ops))
-               page = dma_direct_alloc_pages(dev, size, dma_handle, dir, gfp);
-       else if (ops->alloc_pages)
-               page = ops->alloc_pages(dev, size, dma_handle, dir, gfp);
-       else
+               return dma_direct_alloc_pages(dev, size, dma_handle, dir, gfp);
+       if (!ops->alloc_pages)
                return NULL;
+       return ops->alloc_pages(dev, size, dma_handle, dir, gfp);
+}
 
-       debug_dma_map_page(dev, page, 0, size, dir, *dma_handle);
+struct page *dma_alloc_pages(struct device *dev, size_t size,
+               dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
+{
+       struct page *page = __dma_alloc_pages(dev, size, dma_handle, dir, gfp);
 
+       if (page)
+               debug_dma_map_page(dev, page, 0, size, dir, *dma_handle);
        return page;
 }
 EXPORT_SYMBOL_GPL(dma_alloc_pages);
 
-void dma_free_pages(struct device *dev, size_t size, struct page *page,
+static void __dma_free_pages(struct device *dev, size_t size, struct page *page,
                dma_addr_t dma_handle, enum dma_data_direction dir)
 {
        const struct dma_map_ops *ops = get_dma_ops(dev);
 
        size = PAGE_ALIGN(size);
-       debug_dma_unmap_page(dev, dma_handle, size, dir);
-
        if (dma_alloc_direct(dev, ops))
                dma_direct_free_pages(dev, size, page, dma_handle, dir);
        else if (ops->free_pages)
                ops->free_pages(dev, size, page, dma_handle, dir);
 }
+
+void dma_free_pages(struct device *dev, size_t size, struct page *page,
+               dma_addr_t dma_handle, enum dma_data_direction dir)
+{
+       debug_dma_unmap_page(dev, dma_handle, size, dir);
+       __dma_free_pages(dev, size, page, dma_handle, dir);
+}
 EXPORT_SYMBOL_GPL(dma_free_pages);
 
 int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,