arch/arm/include/asm/xen/page-coherent.h

   1 #ifndef _ASM_ARM_XEN_PAGE_COHERENT_H
   2 #define _ASM_ARM_XEN_PAGE_COHERENT_H
   3
   4 #include <asm/page.h>
   5 #include <linux/dma-attrs.h>
   6 #include <linux/dma-mapping.h>
   7
   8 void __xen_dma_map_page(struct device *hwdev, struct page *page,
   9              dma_addr_t dev_addr, unsigned long offset, size_t size,
  10              enum dma_data_direction dir, struct dma_attrs *attrs);
  11 void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
  12                 size_t size, enum dma_data_direction dir,
  13                 struct dma_attrs *attrs);
  14 void __xen_dma_sync_single_for_cpu(struct device *hwdev,
  15                 dma_addr_t handle, size_t size, enum dma_data_direction dir);
  16
  17 void __xen_dma_sync_single_for_device(struct device *hwdev,
  18                 dma_addr_t handle, size_t size, enum dma_data_direction dir);
  19
  20 static inline void *xen_alloc_coherent_pages(struct device *hwdev, size_t size,
  21                 dma_addr_t *dma_handle, gfp_t flags,
  22                 struct dma_attrs *attrs)
  23 {
  24         return __generic_dma_ops(hwdev)->alloc(hwdev, size, dma_handle, flags, attrs);
  25 }
  26
  27 static inline void xen_free_coherent_pages(struct device *hwdev, size_t size,
  28                 void *cpu_addr, dma_addr_t dma_handle,
  29                 struct dma_attrs *attrs)
  30 {
  31         __generic_dma_ops(hwdev)->free(hwdev, size, cpu_addr, dma_handle, attrs);
  32 }
  33
  34 static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
  35              dma_addr_t dev_addr, unsigned long offset, size_t size,
  36              enum dma_data_direction dir, struct dma_attrs *attrs)
  37 {
  38         bool local = PFN_DOWN(dev_addr) == page_to_pfn(page);
  39         /* Dom0 is mapped 1:1, so if pfn == mfn the page is local otherwise
  40          * is a foreign page grant-mapped in dom0. If the page is local we
  41          * can safely call the native dma_ops function, otherwise we call
  42          * the xen specific function. */
  43         if (local)
  44                 __generic_dma_ops(hwdev)->map_page(hwdev, page, offset, size, dir, attrs);
  45         else
  46                 __xen_dma_map_page(hwdev, page, dev_addr, offset, size, dir, attrs);
  47 }
  48
  49 static inline void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
  50                 size_t size, enum dma_data_direction dir,
  51                 struct dma_attrs *attrs)
  52 {
  53         unsigned long pfn = PFN_DOWN(handle);
  54         /* Dom0 is mapped 1:1, so calling pfn_valid on a foreign mfn will
  55          * always return false. If the page is local we can safely call the
  56          * native dma_ops function, otherwise we call the xen specific
  57          * function. */
  58         if (pfn_valid(pfn)) {
  59                 if (__generic_dma_ops(hwdev)->unmap_page)
  60                         __generic_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);
  61         } else
  62                 __xen_dma_unmap_page(hwdev, handle, size, dir, attrs);
  63 }
  64
  65 static inline void xen_dma_sync_single_for_cpu(struct device *hwdev,
  66                 dma_addr_t handle, size_t size, enum dma_data_direction dir)
  67 {
  68         unsigned long pfn = PFN_DOWN(handle);
  69         if (pfn_valid(pfn)) {
  70                 if (__generic_dma_ops(hwdev)->sync_single_for_cpu)
  71                         __generic_dma_ops(hwdev)->sync_single_for_cpu(hwdev, handle, size, dir);
  72         } else
  73                 __xen_dma_sync_single_for_cpu(hwdev, handle, size, dir);
  74 }
  75
  76 static inline void xen_dma_sync_single_for_device(struct device *hwdev,
  77                 dma_addr_t handle, size_t size, enum dma_data_direction dir)
  78 {
  79         unsigned long pfn = PFN_DOWN(handle);
  80         if (pfn_valid(pfn)) {
  81                 if (__generic_dma_ops(hwdev)->sync_single_for_device)
  82                         __generic_dma_ops(hwdev)->sync_single_for_device(hwdev, handle, size, dir);
  83         } else
  84                 __xen_dma_sync_single_for_device(hwdev, handle, size, dir);
  85 }
  86
  87 #endif /* _ASM_ARM_XEN_PAGE_COHERENT_H */