Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1507536

[net-next PATCH RFC 10/26] arch/m68k: Add option to skip DMA sync as a part of mapping

From Alexander Duyck <alexander.h.duyck@intel.com>
Newsgroups linux.kernel
Subject [net-next PATCH RFC 10/26] arch/m68k: Add option to skip DMA sync as a part of mapping
Date 2016-10-24 20:10 +0200
Message-ID <svRRa-2Kt-111@gated-at.bofh.it> (permalink)
References <svRR7-2Kt-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


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
later via a sync_for_cpu or sync_for_device call.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
---
 arch/m68k/kernel/dma.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
index 8cf97cb..0707006 100644
--- a/arch/m68k/kernel/dma.c
+++ b/arch/m68k/kernel/dma.c
@@ -134,7 +134,9 @@ static dma_addr_t m68k_dma_map_page(struct device *dev, struct page *page,
 {
 	dma_addr_t handle = page_to_phys(page) + offset;
 
-	dma_sync_single_for_device(dev, handle, size, dir);
+	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+		dma_sync_single_for_device(dev, handle, size, dir);
+
 	return handle;
 }
 
@@ -146,6 +148,10 @@ static int m68k_dma_map_sg(struct device *dev, struct scatterlist *sglist,
 
 	for_each_sg(sglist, sg, nents, i) {
 		sg->dma_address = sg_phys(sg);
+
+		if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+			continue;
+
 		dma_sync_single_for_device(dev, sg->dma_address, sg->length,
 					   dir);
 	}

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread


Thread

[net-next PATCH RFC 00/26] Add support for DMA writable pages being  writable by the network stack Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:10 +0200
  [net-next PATCH RFC 26/26] igb: Revert "igb: Revert support for  build_skb in igb" Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:10 +0200
  [net-next PATCH RFC 07/26] arch/c6x: Add option to skip sync on DMA  map and unmap Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:10 +0200
  [net-next PATCH RFC 10/26] arch/m68k: Add option to skip DMA sync  as a part of mapping Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:10 +0200
  [net-next PATCH RFC 13/26] arch/mips: Add option to skip DMA sync  as a part of map and unmap Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:10 +0200
  [net-next PATCH RFC 12/26] arch/microblaze: Add option to skip DMA  sync as a part of map and unmap Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:10 +0200
  Re: [net-next PATCH RFC 01/26] swiotlb: Drop unused function  swiotlb_map_sg Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> - 2016-10-24 20:20 +0200
  [net-next PATCH RFC 02/26] swiotlb: Add support for  DMA_ATTR_SKIP_CPU_SYNC Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:20 +0200
  [net-next PATCH RFC 01/26] swiotlb: Drop unused function  swiotlb_map_sg Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:20 +0200
  [net-next PATCH RFC 09/26] arch/hexagon: Add option to skip DMA  sync as a part of mapping Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:20 +0200
  [net-next PATCH RFC 08/26] arch/frv: Add option to skip sync on DMA  map Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:20 +0200
  [net-next PATCH RFC 15/26] arch/openrisc: Add option to skip DMA  sync as a part of mapping Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:20 +0200
  [net-next PATCH RFC 03/26] arch/arc: Add option to skip sync on DMA  mapping Alexander Duyck <alexander.h.duyck@intel.com> - 2016-10-24 20:20 +0200

csiph-web