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linux/arch/x86/include/asm/dma-mapping.h
FUJITA Tomonori 8d4f5339d1 x86, IA64, powerpc: add phys_to_dma() and dma_to_phys()
This adds two functions, phys_to_dma() and dma_to_phys() to x86, IA64
and powerpc. swiotlb uses them. phys_to_dma() converts a physical
address to a dma address. dma_to_phys() does the opposite.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
2009-07-28 14:19:20 +09:00

161 lines
3.8 KiB
C

#ifndef _ASM_X86_DMA_MAPPING_H
#define _ASM_X86_DMA_MAPPING_H
/*
* IOMMU interface. See Documentation/PCI/PCI-DMA-mapping.txt and
* Documentation/DMA-API.txt for documentation.
*/
#include <linux/kmemcheck.h>
#include <linux/scatterlist.h>
#include <linux/dma-debug.h>
#include <linux/dma-attrs.h>
#include <asm/io.h>
#include <asm/swiotlb.h>
#include <asm-generic/dma-coherent.h>
extern dma_addr_t bad_dma_address;
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)
{
#ifdef CONFIG_X86_32
return dma_ops;
#else
if (unlikely(!dev) || !dev->archdata.dma_ops)
return dma_ops;
else
return dev->archdata.dma_ops;
#endif
}
#include <asm-generic/dma-mapping-common.h>
/* Make sure we keep the same behaviour */
static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
struct dma_map_ops *ops = get_dma_ops(dev);
if (ops->mapping_error)
return ops->mapping_error(dev, dma_addr);
return (dma_addr == bad_dma_address);
}
#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
#define dma_is_consistent(d, h) (1)
extern int dma_supported(struct device *hwdev, u64 mask);
extern int dma_set_mask(struct device *dev, u64 mask);
extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_addr, gfp_t flag);
static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
{
if (!dev->dma_mask)
return 0;
return addr + size <= *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;
}
static inline void
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction dir)
{
flush_write_buffers();
}
static inline int dma_get_cache_alignment(void)
{
/* no easy way to get cache size on all x86, so return the
* maximum possible, to be safe */
return boot_cpu_data.x86_clflush_size;
}
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;
}
static inline void *
dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp)
{
struct dma_map_ops *ops = get_dma_ops(dev);
void *memory;
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
return memory;
if (!dev) {
dev = &x86_dma_fallback_dev;
gfp |= GFP_DMA;
}
if (!is_device_dma_capable(dev))
return NULL;
if (!ops->alloc_coherent)
return NULL;
memory = ops->alloc_coherent(dev, size, dma_handle,
dma_alloc_coherent_gfp_flags(dev, gfp));
debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
return memory;
}
static inline void dma_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t bus)
{
struct dma_map_ops *ops = get_dma_ops(dev);
WARN_ON(irqs_disabled()); /* for portability */
if (dma_release_from_coherent(dev, get_order(size), vaddr))
return;
debug_dma_free_coherent(dev, size, vaddr, bus);
if (ops->free_coherent)
ops->free_coherent(dev, size, vaddr, bus);
}
#endif