linux/arch/x86/include/asm/dma-mapping.h
Christoph Hellwig 6894258eda dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}
Since 2009 we have a nice asm-generic header implementing lots of DMA API
functions for architectures using struct dma_map_ops, but unfortunately
it's still missing a lot of APIs that all architectures still have to
duplicate.

This series consolidates the remaining functions, although we still need
arch opt outs for two of them as a few architectures have very
non-standard implementations.

This patch (of 5):

The coherent DMA allocator works the same over all architectures supporting
dma_map operations.

This patch consolidates them and converges the minor differences:

 - the debug_dma helpers are now called from all architectures, including
   those that were previously missing them
 - dma_alloc_from_coherent and dma_release_from_coherent are now always
   called from the generic alloc/free routines instead of the ops
   dma-mapping-common.h always includes dma-coherent.h to get the defintions
   for them, or the stubs if the architecture doesn't support this feature
 - checks for ->alloc / ->free presence are removed.  There is only one
   magic instead of dma_map_ops without them (mic_dma_ops) and that one
   is x86 only anyway.

Besides that only x86 needs special treatment to replace a default devices
if none is passed and tweak the gfp_flags.  An optional arch hook is provided
for that.

[linux@roeck-us.net: fix build]
[jcmvbkbc@gmail.com: fix xtensa]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00

131 lines
3.3 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 <linux/dma-attrs.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
#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);
debug_dma_mapping_error(dev, dma_addr);
if (ops->mapping_error)
return ops->mapping_error(dev, dma_addr);
return (dma_addr == DMA_ERROR_CODE);
}
#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)
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,
struct dma_attrs *attrs);
extern void dma_generic_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t dma_addr,
struct dma_attrs *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