From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f69.google.com (mail-pa0-f69.google.com [209.85.220.69]) by kanga.kvack.org (Postfix) with ESMTP id E374A6B02AE for ; Wed, 2 Nov 2016 13:16:41 -0400 (EDT) Received: by mail-pa0-f69.google.com with SMTP id hc3so1815618pac.4 for ; Wed, 02 Nov 2016 10:16:41 -0700 (PDT) Received: from mga09.intel.com (mga09.intel.com. [134.134.136.24]) by mx.google.com with ESMTPS id f84si4099790pfd.206.2016.11.02.10.16.41 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 02 Nov 2016 10:16:41 -0700 (PDT) Subject: [mm PATCH v2 21/26] arch/tile: Add option to skip DMA sync as a part of map and unmap From: Alexander Duyck Date: Wed, 02 Nov 2016 07:15:44 -0400 Message-ID: <20161102111542.79519.98990.stgit@ahduyck-blue-test.jf.intel.com> In-Reply-To: <20161102111031.79519.14741.stgit@ahduyck-blue-test.jf.intel.com> References: <20161102111031.79519.14741.stgit@ahduyck-blue-test.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, akpm@linux-foundation.org Cc: netdev@vger.kernel.org, Chris Metcalf , linux-kernel@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: Chris Metcalf Signed-off-by: Alexander Duyck --- arch/tile/kernel/pci-dma.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/tile/kernel/pci-dma.c b/arch/tile/kernel/pci-dma.c index 09bb774..24e0f8c 100644 --- a/arch/tile/kernel/pci-dma.c +++ b/arch/tile/kernel/pci-dma.c @@ -213,10 +213,12 @@ static int tile_dma_map_sg(struct device *dev, struct scatterlist *sglist, for_each_sg(sglist, sg, nents, i) { sg->dma_address = sg_phys(sg); - __dma_prep_pa_range(sg->dma_address, sg->length, direction); #ifdef CONFIG_NEED_SG_DMA_LENGTH sg->dma_length = sg->length; #endif + if (attrs & DMA_ATTR_SKIP_CPU_SYNC) + continue; + __dma_prep_pa_range(sg->dma_address, sg->length, direction); } return nents; @@ -232,6 +234,8 @@ static void tile_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, BUG_ON(!valid_dma_direction(direction)); for_each_sg(sglist, sg, nents, i) { sg->dma_address = sg_phys(sg); + if (attrs & DMA_ATTR_SKIP_CPU_SYNC) + continue; __dma_complete_pa_range(sg->dma_address, sg->length, direction); } @@ -245,7 +249,8 @@ static dma_addr_t tile_dma_map_page(struct device *dev, struct page *page, BUG_ON(!valid_dma_direction(direction)); BUG_ON(offset + size > PAGE_SIZE); - __dma_prep_page(page, offset, size, direction); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + __dma_prep_page(page, offset, size, direction); return page_to_pa(page) + offset; } @@ -256,6 +261,9 @@ static void tile_dma_unmap_page(struct device *dev, dma_addr_t dma_address, { BUG_ON(!valid_dma_direction(direction)); + if (attrs & DMA_ATTR_SKIP_CPU_SYNC) + return; + __dma_complete_page(pfn_to_page(PFN_DOWN(dma_address)), dma_address & (PAGE_SIZE - 1), size, direction); } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org