alistair23-linux/include/xen/page.h
Julien Grall 1084b1988d xen: Add Xen specific page definition
The Xen hypercall interface is always using 4K page granularity on ARM
and x86 architecture.

With the incoming support of 64K page granularity for ARM64 guest, it
won't be possible to re-use the Linux page definition in Xen drivers.

Introduce Xen page definition helpers based on the Linux page
definition. They have exactly the same name but prefixed with
XEN_/xen_ prefix.

Also modify xen_page_to_gfn to use new Xen page definition.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:33 +01:00

49 lines
1.3 KiB
C

#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_xen_pfn(page));
}
struct xen_memory_region {
unsigned long start_pfn;
unsigned long n_pfns;
};
#define XEN_EXTRA_MEM_MAX_REGIONS 128 /* == E820MAX */
extern __initdata
struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS];
extern unsigned long xen_released_pages;
#endif /* _XEN_PAGE_H */