LXR linux/include/xen/page.h

   1#ifndef _XEN_PAGE_H
   2#define _XEN_PAGE_H
   3
   4#include <asm/page.h>
   5
   6/* The hypercall interface supports only 4KB page */
   7#define XEN_PAGE_SHIFT  12
   8#define XEN_PAGE_SIZE   (_AC(1, UL) << XEN_PAGE_SHIFT)
   9#define XEN_PAGE_MASK   (~(XEN_PAGE_SIZE-1))
  10#define xen_offset_in_page(p)   ((unsigned long)(p) & ~XEN_PAGE_MASK)
  11
  12/*
  13 * We assume that PAGE_SIZE is a multiple of XEN_PAGE_SIZE
  14 * XXX: Add a BUILD_BUG_ON?
  15 */
  16
  17#define xen_pfn_to_page(xen_pfn)        \
  18        (pfn_to_page((unsigned long)(xen_pfn) >> (PAGE_SHIFT - XEN_PAGE_SHIFT)))
  19#define page_to_xen_pfn(page)           \
  20        ((page_to_pfn(page)) << (PAGE_SHIFT - XEN_PAGE_SHIFT))
  21
  22#define XEN_PFN_PER_PAGE        (PAGE_SIZE / XEN_PAGE_SIZE)
  23
  24#define XEN_PFN_DOWN(x) ((x) >> XEN_PAGE_SHIFT)
  25#define XEN_PFN_UP(x)   (((x) + XEN_PAGE_SIZE-1) >> XEN_PAGE_SHIFT)
  26#define XEN_PFN_PHYS(x) ((phys_addr_t)(x) << XEN_PAGE_SHIFT)
  27
  28#include <asm/xen/page.h>
  29
  30/* Return the GFN associated to the first 4KB of the page */
  31static inline unsigned long xen_page_to_gfn(struct page *page)
  32{
  33        return pfn_to_gfn(page_to_xen_pfn(page));
  34}
  35
  36struct xen_memory_region {
  37        unsigned long start_pfn;
  38        unsigned long n_pfns;
  39};
  40
  41#define XEN_EXTRA_MEM_MAX_REGIONS 128 /* == E820MAX */
  42
  43extern __initdata
  44struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS];
  45
  46extern unsigned long xen_released_pages;
  47
  48#endif  /* _XEN_PAGE_H */
  49