[net-next PATCH RFC 19/26] arch/sparc: Add option to skip DMA sync as a part of map and unmap
From: Alexander Duyck <hidden>
Date: 2016-10-24 18:06:48
Also in:
linux-mm, lkml, sparclinux
Subsystem:
sparc + ultrasparc (sparc/sparc64), the rest · Maintainers:
"David S. Miller", Andreas Larsson, Linus Torvalds
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: "David S. Miller" <davem@davemloft.net> Cc: sparclinux@vger.kernel.org Signed-off-by: Alexander Duyck <redacted> --- arch/sparc/kernel/iommu.c | 4 ++-- arch/sparc/kernel/ioport.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/sparc/kernel/iommu.c b/arch/sparc/kernel/iommu.c
index 5c615ab..8fda4e4 100644
--- a/arch/sparc/kernel/iommu.c
+++ b/arch/sparc/kernel/iommu.c@@ -415,7 +415,7 @@ static void dma_4u_unmap_page(struct device *dev, dma_addr_t bus_addr, ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL; /* Step 1: Kick data out of streaming buffers if necessary. */ - if (strbuf->strbuf_enabled) + if (strbuf->strbuf_enabled && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
@@ -640,7 +640,7 @@ static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist, base = iommu->page_table + entry; dma_handle &= IO_PAGE_MASK; - if (strbuf->strbuf_enabled) + if (strbuf->strbuf_enabled && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) strbuf_flush(strbuf, iommu, dma_handle, ctx, npages, direction);
diff --git a/arch/sparc/kernel/ioport.c b/arch/sparc/kernel/ioport.c
index 2344103..6ffaec4 100644
--- a/arch/sparc/kernel/ioport.c
+++ b/arch/sparc/kernel/ioport.c@@ -527,7 +527,7 @@ static dma_addr_t pci32_map_page(struct device *dev, struct page *page, static void pci32_unmap_page(struct device *dev, dma_addr_t ba, size_t size, enum dma_data_direction dir, unsigned long attrs) { - if (dir != PCI_DMA_TODEVICE) + if (dir != PCI_DMA_TODEVICE && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) dma_make_coherent(ba, PAGE_ALIGN(size)); }
@@ -572,7 +572,7 @@ static void pci32_unmap_sg(struct device *dev, struct scatterlist *sgl, struct scatterlist *sg; int n; - if (dir != PCI_DMA_TODEVICE) { + if (dir != PCI_DMA_TODEVICE && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) { for_each_sg(sgl, sg, nents, n) { dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length)); }