Commit efa70f2f authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

dma-mapping: add a new dma_alloc_pages API 



This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device.  The
implementation will also be used to provide a more sensible replacement
for DMA_ATTR_NON_CONSISTENT flag.

Additionally dma_alloc_noncoherent is switched over to use dma_alloc_pages
as its backend.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
parent 5a842922

Documentation/core-api/dma-attributes.rst

+0 −8
Original line number Diff line number Diff line
@@ -25,14 +25,6 @@ Since it is optional for platforms to implement DMA_ATTR_WRITE_COMBINE, 
those that do not will simply ignore the attribute and exhibit default

behavior.



DMA_ATTR_NON_CONSISTENT

-----------------------



DMA_ATTR_NON_CONSISTENT lets the platform to choose to return either

consistent or non-consistent memory as it sees fit.  By using this API,

you are guaranteeing to the platform that you have all the correct and

necessary sync points for this memory in the driver.



DMA_ATTR_NO_KERNEL_MAPPING

--------------------------

arch/alpha/kernel/pci_iommu.c

+2 −0
Original line number Diff line number Diff line
@@ -952,5 +952,7 @@ const struct dma_map_ops alpha_pci_ops = { 
	.dma_supported		= alpha_pci_supported,

	.mmap			= dma_common_mmap,

	.get_sgtable		= dma_common_get_sgtable,

	.alloc_pages		= dma_common_alloc_pages,

	.free_pages		= dma_common_free_pages,

};

EXPORT_SYMBOL(alpha_pci_ops);

arch/arm/mm/dma-mapping-nommu.c

+2 −0
Original line number Diff line number Diff line
@@ -176,6 +176,8 @@ static void arm_nommu_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist 
const struct dma_map_ops arm_nommu_dma_ops = {

	.alloc			= arm_nommu_dma_alloc,

	.free			= arm_nommu_dma_free,

	.alloc_pages		= dma_direct_alloc_pages,

	.free_pages		= dma_direct_free_pages,

	.mmap			= arm_nommu_dma_mmap,

	.map_page		= arm_nommu_dma_map_page,

	.unmap_page		= arm_nommu_dma_unmap_page,

arch/arm/mm/dma-mapping.c

+4 −0
Original line number Diff line number Diff line
@@ -199,6 +199,8 @@ static int arm_dma_supported(struct device *dev, u64 mask) 
const struct dma_map_ops arm_dma_ops = {

	.alloc			= arm_dma_alloc,

	.free			= arm_dma_free,

	.alloc_pages		= dma_direct_alloc_pages,

	.free_pages		= dma_direct_free_pages,

	.mmap			= arm_dma_mmap,

	.get_sgtable		= arm_dma_get_sgtable,

	.map_page		= arm_dma_map_page,
@@ -226,6 +228,8 @@ static int arm_coherent_dma_mmap(struct device *dev, struct vm_area_struct *vma, 
const struct dma_map_ops arm_coherent_dma_ops = {

	.alloc			= arm_coherent_dma_alloc,

	.free			= arm_coherent_dma_free,

	.alloc_pages		= dma_direct_alloc_pages,

	.free_pages		= dma_direct_free_pages,

	.mmap			= arm_coherent_dma_mmap,

	.get_sgtable		= arm_dma_get_sgtable,

	.map_page		= arm_coherent_dma_map_page,

arch/ia64/hp/common/sba_iommu.c

+2 −0
Original line number Diff line number Diff line
@@ -2070,6 +2070,8 @@ static const struct dma_map_ops sba_dma_ops = { 
	.dma_supported		= sba_dma_supported,

	.mmap			= dma_common_mmap,

	.get_sgtable		= dma_common_get_sgtable,

	.alloc_pages		= dma_common_alloc_pages,

	.free_pages		= dma_common_free_pages,

};



static int __init

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