![Krzysztof Kozlowski](/assets/img/avatar_default.png)
The dma-mapping core and the implementations do not change the DMA attributes passed by pointer. Thus the pointer can point to const data. However the attributes do not have to be a bitfield. Instead unsigned long will do fine: 1. This is just simpler. Both in terms of reading the code and setting attributes. Instead of initializing local attributes on the stack and passing pointer to it to dma_set_attr(), just set the bits. 2. It brings safeness and checking for const correctness because the attributes are passed by value. Semantic patches for this change (at least most of them): virtual patch virtual context @r@ identifier f, attrs; @@ f(..., - struct dma_attrs *attrs + unsigned long attrs , ...) { ... } @@ identifier r.f; @@ f(..., - NULL + 0 ) and // Options: --all-includes virtual patch virtual context @r@ identifier f, attrs; type t; @@ t f(..., struct dma_attrs *attrs); @@ identifier r.f; @@ f(..., - NULL + 0 ) Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> Acked-by: Mark Salter <msalter@redhat.com> [c6x] Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris] Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm] Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Acked-by: Joerg Roedel <jroedel@suse.de> [iommu] Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp] Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core] Acked-by: David Vrabel <david.vrabel@citrix.com> [xen] Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb] Acked-by: Joerg Roedel <jroedel@suse.de> [iommu] Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32] Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc] Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
114 lines
2.7 KiB
C
114 lines
2.7 KiB
C
#ifndef _ASM_X86_DMA_MAPPING_H
|
|
#define _ASM_X86_DMA_MAPPING_H
|
|
|
|
/*
|
|
* IOMMU interface. See Documentation/DMA-API-HOWTO.txt and
|
|
* Documentation/DMA-API.txt for documentation.
|
|
*/
|
|
|
|
#include <linux/kmemcheck.h>
|
|
#include <linux/scatterlist.h>
|
|
#include <linux/dma-debug.h>
|
|
#include <asm/io.h>
|
|
#include <asm/swiotlb.h>
|
|
#include <linux/dma-contiguous.h>
|
|
|
|
#ifdef CONFIG_ISA
|
|
# define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
|
|
#else
|
|
# define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
|
|
#endif
|
|
|
|
#define DMA_ERROR_CODE 0
|
|
|
|
extern int iommu_merge;
|
|
extern struct device x86_dma_fallback_dev;
|
|
extern int panic_on_overflow;
|
|
|
|
extern struct dma_map_ops *dma_ops;
|
|
|
|
static inline struct dma_map_ops *get_dma_ops(struct device *dev)
|
|
{
|
|
#ifndef CONFIG_X86_DEV_DMA_OPS
|
|
return dma_ops;
|
|
#else
|
|
if (unlikely(!dev) || !dev->archdata.dma_ops)
|
|
return dma_ops;
|
|
else
|
|
return dev->archdata.dma_ops;
|
|
#endif
|
|
}
|
|
|
|
bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp);
|
|
#define arch_dma_alloc_attrs arch_dma_alloc_attrs
|
|
|
|
#define HAVE_ARCH_DMA_SUPPORTED 1
|
|
extern int dma_supported(struct device *hwdev, u64 mask);
|
|
|
|
extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
|
|
dma_addr_t *dma_addr, gfp_t flag,
|
|
unsigned long attrs);
|
|
|
|
extern void dma_generic_free_coherent(struct device *dev, size_t size,
|
|
void *vaddr, dma_addr_t dma_addr,
|
|
unsigned long attrs);
|
|
|
|
#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
|
|
extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
|
|
extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
|
|
extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
|
|
#else
|
|
|
|
static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
|
|
{
|
|
if (!dev->dma_mask)
|
|
return 0;
|
|
|
|
return addr + size - 1 <= *dev->dma_mask;
|
|
}
|
|
|
|
static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
|
|
{
|
|
return paddr;
|
|
}
|
|
|
|
static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
|
|
{
|
|
return daddr;
|
|
}
|
|
#endif /* CONFIG_X86_DMA_REMAP */
|
|
|
|
static inline void
|
|
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
|
|
enum dma_data_direction dir)
|
|
{
|
|
flush_write_buffers();
|
|
}
|
|
|
|
static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
|
|
gfp_t gfp)
|
|
{
|
|
unsigned long dma_mask = 0;
|
|
|
|
dma_mask = dev->coherent_dma_mask;
|
|
if (!dma_mask)
|
|
dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
|
|
|
|
return dma_mask;
|
|
}
|
|
|
|
static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
|
|
{
|
|
unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
|
|
|
|
if (dma_mask <= DMA_BIT_MASK(24))
|
|
gfp |= GFP_DMA;
|
|
#ifdef CONFIG_X86_64
|
|
if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
|
|
gfp |= GFP_DMA32;
|
|
#endif
|
|
return gfp;
|
|
}
|
|
|
|
#endif
|