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author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-09 17:18:14 +0000 |
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committer | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-09 17:18:14 +0000 |
commit | d6fe76c58c358498b91d21f0ca8054f6aa6e672d (patch) | |
tree | 7a351e4ddefe07831842757ddd32b46156bc69a4 /arch/ia64 | |
parent | 58c8b26909f287c72a7a39d26f800ffe61e01bf3 (diff) | |
download | linux-d6fe76c58c358498b91d21f0ca8054f6aa6e672d.tar.bz2 |
xen: introduce xen_alloc/free_coherent_pages
xen_swiotlb_alloc_coherent needs to allocate a coherent buffer for cpu
and devices. On native x86 is sufficient to call __get_free_pages in
order to get a coherent buffer, while on ARM (and potentially ARM64) we
need to call the native dma_ops->alloc implementation.
Introduce xen_alloc_coherent_pages to abstract the arch specific buffer
allocation.
Similarly introduce xen_free_coherent_pages to free a coherent buffer:
on x86 is simply a call to free_pages while on ARM and ARM64 is
arm_dma_ops.free.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Changes in v7:
- rename __get_dma_ops to __generic_dma_ops;
- call __generic_dma_ops(hwdev)->alloc/free on arm64 too.
Changes in v6:
- call __get_dma_ops to get the native dma_ops pointer on arm.
Diffstat (limited to 'arch/ia64')
-rw-r--r-- | arch/ia64/include/asm/xen/page-coherent.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/ia64/include/asm/xen/page-coherent.h b/arch/ia64/include/asm/xen/page-coherent.h new file mode 100644 index 000000000000..37b929c117bf --- /dev/null +++ b/arch/ia64/include/asm/xen/page-coherent.h @@ -0,0 +1,24 @@ +#ifndef _ASM_IA64_XEN_PAGE_COHERENT_H +#define _ASM_IA64_XEN_PAGE_COHERENT_H + +#include <asm/page.h> +#include <linux/dma-attrs.h> +#include <linux/dma-mapping.h> + +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) +{ + void *vstart = (void*)__get_free_pages(flags, get_order(size)); + *dma_handle = virt_to_phys(vstart); + return vstart; +} + +static inline void xen_free_coherent_pages(struct device *hwdev, size_t size, + void *cpu_addr, dma_addr_t dma_handle, + struct dma_attrs *attrs) +{ + free_pages((unsigned long) cpu_addr, get_order(size)); +} + +#endif /* _ASM_IA64_XEN_PAGE_COHERENT_H */ |