From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Duyck Date: Mon, 24 Oct 2016 12:06:01 +0000 Subject: [net-next PATCH RFC 18/26] arch/sh: Add option to skip DMA sync as a part of mapping Message-Id: <20161024120601.16276.5500.stgit@ahduyck-blue-test.jf.intel.com> List-Id: References: <20161024115737.16276.71059.stgit@ahduyck-blue-test.jf.intel.com> In-Reply-To: <20161024115737.16276.71059.stgit@ahduyck-blue-test.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: brouer@redhat.com, Rich Felker , davem@davemloft.net, Yoshinori Sato , linux-sh@vger.kernel.org This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to avoid invoking cache line invalidation if the driver will just handle it via a sync_for_cpu or sync_for_device call. Cc: Yoshinori Sato Cc: Rich Felker Cc: linux-sh@vger.kernel.org Signed-off-by: Alexander Duyck --- arch/sh/kernel/dma-nommu.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/sh/kernel/dma-nommu.c b/arch/sh/kernel/dma-nommu.c index eadb669..47fee3b 100644 --- a/arch/sh/kernel/dma-nommu.c +++ b/arch/sh/kernel/dma-nommu.c @@ -18,7 +18,9 @@ static dma_addr_t nommu_map_page(struct device *dev, struct page *page, dma_addr_t addr = page_to_phys(page) + offset; WARN_ON(size = 0); - dma_cache_sync(dev, page_address(page) + offset, size, dir); + + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_cache_sync(dev, page_address(page) + offset, size, dir); return addr; } @@ -35,7 +37,8 @@ static int nommu_map_sg(struct device *dev, struct scatterlist *sg, for_each_sg(sg, s, nents, i) { BUG_ON(!sg_page(s)); - dma_cache_sync(dev, sg_virt(s), s->length, dir); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_cache_sync(dev, sg_virt(s), s->length, dir); s->dma_address = sg_phys(s); s->dma_length = s->length;