linux/include/asm-m68k/dma-mapping.h
FUJITA Tomonori 8d8bb39b9e dma-mapping: add the device argument to dma_mapping_error()
Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
architecture does:

This enables us to cleanly fix the Calgary IOMMU issue that some devices
are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423).

I think that per-device dma_mapping_ops support would be also helpful for
KVM people to support PCI passthrough but Andi thinks that this makes it
difficult to support the PCI passthrough (see the above thread).  So I
CC'ed this to KVM camp.  Comments are appreciated.

A pointer to dma_mapping_ops to struct dev_archdata is added.  If the
pointer is non NULL, DMA operations in asm/dma-mapping.h use it.  If it's
NULL, the system-wide dma_ops pointer is used as before.

If it's useful for KVM people, I plan to implement a mechanism to register
a hook called when a new pci (or dma capable) device is created (it works
with hot plugging).  It enables IOMMUs to set up an appropriate
dma_mapping_ops per device.

The major obstacle is that dma_mapping_error doesn't take a pointer to the
device unlike other DMA operations.  So x86 can't have dma_mapping_ops per
device.  Note all the POWER IOMMUs use the same dma_mapping_error function
so this is not a problem for POWER but x86 IOMMUs use different
dma_mapping_error functions.

The first patch adds the device argument to dma_mapping_error.  The patch
is trivial but large since it touches lots of drivers and dma-mapping.h in
all the architecture.

This patch:

dma_mapping_error() doesn't take a pointer to the device unlike other DMA
operations.  So we can't have dma_mapping_ops per device.

Note that POWER already has dma_mapping_ops per device but all the POWER
IOMMUs use the same dma_mapping_error function.  x86 IOMMUs use device
argument.

[akpm@linux-foundation.org: fix sge]
[akpm@linux-foundation.org: fix svc_rdma]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix bnx2x]
[akpm@linux-foundation.org: fix s2io]
[akpm@linux-foundation.org: fix pasemi_mac]
[akpm@linux-foundation.org: fix sdhci]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc]
[akpm@linux-foundation.org: fix ibmvscsi]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:03 -07:00

97 lines
2.5 KiB
C

#ifndef _M68K_DMA_MAPPING_H
#define _M68K_DMA_MAPPING_H
#include <asm/cache.h>
struct scatterlist;
#ifndef CONFIG_MMU_SUN3
static inline int dma_supported(struct device *dev, u64 mask)
{
return 1;
}
static inline int dma_set_mask(struct device *dev, u64 mask)
{
return 0;
}
static inline int dma_get_cache_alignment(void)
{
return 1 << L1_CACHE_SHIFT;
}
static inline int dma_is_consistent(struct device *dev, dma_addr_t dma_addr)
{
return 0;
}
extern void *dma_alloc_coherent(struct device *, size_t,
dma_addr_t *, gfp_t);
extern void dma_free_coherent(struct device *, size_t,
void *, dma_addr_t);
static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t flag)
{
return dma_alloc_coherent(dev, size, handle, flag);
}
static inline void dma_free_noncoherent(struct device *dev, size_t size,
void *addr, dma_addr_t handle)
{
dma_free_coherent(dev, size, addr, handle);
}
static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction dir)
{
/* we use coherent allocation, so not much to do here. */
}
extern dma_addr_t dma_map_single(struct device *, void *, size_t,
enum dma_data_direction);
static inline void dma_unmap_single(struct device *dev, dma_addr_t addr,
size_t size, enum dma_data_direction dir)
{
}
extern dma_addr_t dma_map_page(struct device *, struct page *,
unsigned long, size_t size,
enum dma_data_direction);
static inline void dma_unmap_page(struct device *dev, dma_addr_t address,
size_t size, enum dma_data_direction dir)
{
}
extern int dma_map_sg(struct device *, struct scatterlist *, int,
enum dma_data_direction);
static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
int nhwentries, enum dma_data_direction dir)
{
}
extern void dma_sync_single_for_device(struct device *, dma_addr_t, size_t,
enum dma_data_direction);
extern void dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
enum dma_data_direction);
static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
}
static inline void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir)
{
}
static inline int dma_mapping_error(struct device *dev, dma_addr_t handle)
{
return 0;
}
#else
#include <asm-generic/dma-mapping-broken.h>
#endif
#endif /* _M68K_DMA_MAPPING_H */