LXR linux/include/xen/page.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _XEN_PAGE_H
   3#define _XEN_PAGE_H
   4
   5#include <asm/page.h>
   6
   7/* The hypercall interface supports only 4KB page */
   8#define XEN_PAGE_SHIFT  12
   9#define XEN_PAGE_SIZE   (_AC(1, UL) << XEN_PAGE_SHIFT)
  10#define XEN_PAGE_MASK   (~(XEN_PAGE_SIZE-1))
  11#define xen_offset_in_page(p)   ((unsigned long)(p) & ~XEN_PAGE_MASK)
  12
  13/*
  14 * We assume that PAGE_SIZE is a multiple of XEN_PAGE_SIZE
  15 * XXX: Add a BUILD_BUG_ON?
  16 */
  17
  18#define xen_pfn_to_page(xen_pfn)        \
  19        (pfn_to_page((unsigned long)(xen_pfn) >> (PAGE_SHIFT - XEN_PAGE_SHIFT)))
  20#define page_to_xen_pfn(page)           \
  21        ((page_to_pfn(page)) << (PAGE_SHIFT - XEN_PAGE_SHIFT))
  22
  23#define XEN_PFN_PER_PAGE        (PAGE_SIZE / XEN_PAGE_SIZE)
  24
  25#define XEN_PFN_DOWN(x) ((x) >> XEN_PAGE_SHIFT)
  26#define XEN_PFN_UP(x)   (((x) + XEN_PAGE_SIZE-1) >> 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 /* == E820_MAX_ENTRIES_ZEROPAGE */
  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