[net-next PATCH V2 3/3] page_pool: use DMA_ATTR_SKIP_CPU_SYNC for DMA mappings

[Jesper Dangaard Brouer]

As pointed out by Alexander Duyck, the DMA mapping done in page_pool needs
to use the DMA attribute DMA_ATTR_SKIP_CPU_SYNC.

As the principle behind page_pool keeping the pages mapped is that the
driver takes over the DMA-sync steps.

Signed-off-by: Jesper Dangaard Brouer <bro...@redhat.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
---
 net/core/page_pool.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 897a69a1477e..7e624c2cd709 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -141,9 +141,9 @@ static struct page *__page_pool_alloc_pages_slow(struct 
page_pool *pool,
         * into page private data (i.e 32bit cpu with 64bit DMA caps)
         * This mapping is kept for lifetime of page, until leaving pool.
         */
-       dma = dma_map_page(pool->p.dev, page, 0,
-                          (PAGE_SIZE << pool->p.order),
-                          pool->p.dma_dir);
+       dma = dma_map_page_attrs(pool->p.dev, page, 0,
+                                (PAGE_SIZE << pool->p.order),
+                                pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
        if (dma_mapping_error(pool->p.dev, dma)) {
                put_page(page);
                return NULL;
@@ -184,8 +184,9 @@ static void __page_pool_clean_page(struct page_pool *pool,
 
        dma = page->dma_addr;
        /* DMA unmap */
-       dma_unmap_page(pool->p.dev, dma,
-                      PAGE_SIZE << pool->p.order, pool->p.dma_dir);
+       dma_unmap_page_attr(pool->p.dev, dma,
+                           PAGE_SIZE << pool->p.order, pool->p.dma_dir,
+                           DMA_ATTR_SKIP_CPU_SYNC);
        page->dma_addr = 0;
 }