Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ea8c64ac authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

dma-mapping: move swiotlb arch helpers to a new header 



phys_to_dma, dma_to_phys and dma_capable are helpers published by
architecture code for use of swiotlb and xen-swiotlb only.  Drivers are
not supposed to use these directly, but use the DMA API instead.

Move these to a new asm/dma-direct.h helper, included by a
linux/dma-direct.h wrapper that provides the default linear mapping
unless the architecture wants to override it.

In the MIPS case the existing dma-coherent.h is reused for now as
untangling it will take a bit of work.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarRobin Murphy <robin.murphy@arm.com>
parent 10dac04c

MAINTAINERS

+1 −0
Original line number Diff line number Diff line
@@ -4338,6 +4338,7 @@ F: lib/dma-noop.c 
F:	lib/dma-virt.c

F:	drivers/base/dma-mapping.c

F:	drivers/base/dma-coherent.c

F:	include/linux/dma-direct.h

F:	include/linux/dma-mapping.h



DME1737 HARDWARE MONITOR DRIVER

arch/Kconfig

+4 −0
Original line number Diff line number Diff line
@@ -938,6 +938,10 @@ config STRICT_MODULE_RWX 
	  and non-text memory will be made non-executable. This provides

	  protection against certain security exploits (e.g. writing to text)



# select if the architecture provides an asm/dma-direct.h header

config ARCH_HAS_PHYS_TO_DMA

	bool



config ARCH_HAS_REFCOUNT

	bool

	help

arch/arm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ config ARM 
	select ARCH_HAS_DEVMEM_IS_ALLOWED

	select ARCH_HAS_ELF_RANDOMIZE

	select ARCH_HAS_SET_MEMORY

	select ARCH_HAS_PHYS_TO_DMA

	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL

	select ARCH_HAS_STRICT_MODULE_RWX if MMU

	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST

arch/arm/include/asm/dma-direct.h

0 → 100644
+36 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef ASM_ARM_DMA_DIRECT_H

#define ASM_ARM_DMA_DIRECT_H 1



static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

{

	unsigned int offset = paddr & ~PAGE_MASK;

	return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;

}



static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)

{

	unsigned int offset = dev_addr & ~PAGE_MASK;

	return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;

}



static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)

{

	u64 limit, mask;



	if (!dev->dma_mask)

		return 0;



	mask = *dev->dma_mask;



	limit = (mask + 1) & ~mask;

	if (limit && size > limit)

		return 0;



	if ((addr | (addr + size - 1)) & ~mask)

		return 0;



	return 1;

}



#endif /* ASM_ARM_DMA_DIRECT_H */

arch/arm/include/asm/dma-mapping.h

+0 −31
Original line number Diff line number Diff line
@@ -109,37 +109,6 @@ static inline bool is_device_dma_coherent(struct device *dev) 
	return dev->archdata.dma_coherent;

}



static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

{

	unsigned int offset = paddr & ~PAGE_MASK;

	return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;

}



static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)

{

	unsigned int offset = dev_addr & ~PAGE_MASK;

	return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;

}



static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)

{

	u64 limit, mask;



	if (!dev->dma_mask)

		return 0;



	mask = *dev->dma_mask;



	limit = (mask + 1) & ~mask;

	if (limit && size > limit)

		return 0;



	if ((addr | (addr + size - 1)) & ~mask)

		return 0;



	return 1;

}



static inline void dma_mark_clean(void *addr, size_t size) { }



/**