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xen/arm: if(pfn_valid(pfn)) call native dma_ops

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Remove code duplication in mm32.c by calling the native dma_ops if the
page is a local page (not a foreign page). Use a simple pfn_valid(pfn)
check to figure out if the page is local, exploiting the fact that dom0
is mapped 1:1, therefore pfn_valid always returns false when called on a
foreign mfn.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Stefano Stabellini
2014-11-11 14:31:56 +00:00
committed by David Vrabel
parent 35e0be88c4
commit 2f91fc331a
2 changed files with 54 additions and 45 deletions
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49
arch/arm/include/asm/xen/page-coherent.h
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@@ -5,6 +5,15 @@
#include <linux/dma-attrs.h>
#include <linux/dma-mapping.h>
void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs);
void __xen_dma_sync_single_for_cpu(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir);
void __xen_dma_sync_single_for_device(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir);
static inline void *xen_alloc_coherent_pages(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flags,
struct dma_attrs *attrs)
@@ -26,14 +35,42 @@ static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
__generic_dma_ops(hwdev)->map_page(hwdev, page, offset, size, dir, attrs);
}
void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
static inline void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs);
struct dma_attrs *attrs)
{
unsigned long pfn = PFN_DOWN(handle);
/* Dom0 is mapped 1:1, so calling pfn_valid on a foreign mfn will
* always return false. If the page is local we can safely call the
* native dma_ops function, otherwise we call the xen specific
* function. */
if (pfn_valid(pfn)) {
if (__generic_dma_ops(hwdev)->unmap_page)
__generic_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);
} else
__xen_dma_unmap_page(hwdev, handle, size, dir, attrs);
}
void xen_dma_sync_single_for_cpu(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir);
static inline void xen_dma_sync_single_for_cpu(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
unsigned long pfn = PFN_DOWN(handle);
if (pfn_valid(pfn)) {
if (__generic_dma_ops(hwdev)->sync_single_for_cpu)
__generic_dma_ops(hwdev)->sync_single_for_cpu(hwdev, handle, size, dir);
} else
__xen_dma_sync_single_for_cpu(hwdev, handle, size, dir);
}
void xen_dma_sync_single_for_device(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir);
static inline void xen_dma_sync_single_for_device(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
unsigned long pfn = PFN_DOWN(handle);
if (pfn_valid(pfn)) {
if (__generic_dma_ops(hwdev)->sync_single_for_device)
__generic_dma_ops(hwdev)->sync_single_for_device(hwdev, handle, size, dir);
} else
__xen_dma_sync_single_for_device(hwdev, handle, size, dir);
}
#endif /* _ASM_ARM_XEN_PAGE_COHERENT_H */