[PATCH 24/33] dma-direct: use phys_to_dma
From: Christoph Hellwig <hch@lst.de>
Date: 2018-01-10 08:05:46
Also in:
linux-arch, linux-arm-kernel, linux-iommu, linux-mips, linux-s390, linux-sh, linuxppc-dev, lkml, sparclinux
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
This means it uses whatever linear remapping scheme that the architecture provides is used in the generic dma_direct ops. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Vladimir Murzin <redacted> --- lib/dma-direct.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-)
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 0ec3262a3148..12ea9653781b 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c@@ -1,12 +1,11 @@ // SPDX-License-Identifier: GPL-2.0 /* - * lib/dma-noop.c - * - * DMA operations that map to physical addresses without flushing memory. + * DMA operations that map physical memory directly without using an IOMMU or + * flushing caches. */ #include <linux/export.h> #include <linux/mm.h> -#include <linux/dma-mapping.h> +#include <linux/dma-direct.h> #include <linux/scatterlist.h> #include <linux/pfn.h>
@@ -17,7 +16,7 @@ static void *dma_direct_alloc(struct device *dev, size_t size, ret = (void *)__get_free_pages(gfp, get_order(size)); if (ret) - *dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset); + *dma_handle = phys_to_dma(dev, virt_to_phys(ret)); return ret; }
@@ -32,7 +31,7 @@ static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs) { - return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset); + return phys_to_dma(dev, page_to_phys(page)) + offset; } static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
@@ -42,12 +41,9 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, struct scatterlist *sg; for_each_sg(sgl, sg, nents, i) { - dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset); - void *va; - BUG_ON(!sg_page(sg)); - va = sg_virt(sg); - sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset; + + sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg)); sg_dma_len(sg) = sg->length; }
--
2.14.2