1 files changed, 26 insertions, 1 deletions

diff --git a/include/xen/page.h b/include/xen/page.h
index 1daae485e336..96294ac93755 100644
--- a/include/xen/page.h
+++ b/include/xen/page.h
@@ -1,11 +1,36 @@
 #ifndef _XEN_PAGE_H
 #define _XEN_PAGE_H
 
+#include <asm/page.h>
+
+/* The hypercall interface supports only 4KB page */
+#define XEN_PAGE_SHIFT  12
+#define XEN_PAGE_SIZE   (_AC(1, UL) << XEN_PAGE_SHIFT)
+#define XEN_PAGE_MASK   (~(XEN_PAGE_SIZE-1))
+#define xen_offset_in_page(p)   ((unsigned long)(p) & ~XEN_PAGE_MASK)
+
+/*
+ * We assume that PAGE_SIZE is a multiple of XEN_PAGE_SIZE
+ * XXX: Add a BUILD_BUG_ON?
+ */
+
+#define xen_pfn_to_page(xen_pfn)        \
+        ((pfn_to_page(((unsigned long)(xen_pfn) << XEN_PAGE_SHIFT) >> PAGE_SHIFT)))
+#define page_to_xen_pfn(page)           \
+        (((page_to_pfn(page)) << PAGE_SHIFT) >> XEN_PAGE_SHIFT)
+
+#define XEN_PFN_PER_PAGE        (PAGE_SIZE / XEN_PAGE_SIZE)
+
+#define XEN_PFN_DOWN(x) ((x) >> XEN_PAGE_SHIFT)
+#define XEN_PFN_UP(x)   (((x) + XEN_PAGE_SIZE-1) >> XEN_PAGE_SHIFT)
+#define XEN_PFN_PHYS(x) ((phys_addr_t)(x) << XEN_PAGE_SHIFT)
+
 #include <asm/xen/page.h>
 
+/* Return the GFN associated to the first 4KB of the page */
 static inline unsigned long xen_page_to_gfn(struct page *page)
 {
-        return pfn_to_gfn(page_to_pfn(page));
+        return pfn_to_gfn(page_to_xen_pfn(page));
 }
 
 struct xen_memory_region {