| Message ID | 1438966019-19322-4-git-send-email-julien.grall@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 7 Aug 2015, Julien Grall wrote: > 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> > > --- > Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> > Cc: David Vrabel <david.vrabel@citrix.com> > > Changes in v3: > - Fix errors reported by checkpatch.pl > - Rename pfn to xen_pfn in xen_pfn_to_page > - Add a comment that we assume PAGE_SIZE to be a multiple of > XEN_PAGE_SIZE > - s/MFN/GFN/ according to new naming > - Add Stefano's reviewed-by > > Changes in v2: > - Add XEN_PFN_UP > - Add a comment describing the behavior of page_to_pfn > --- > include/xen/page.h | 27 ++++++++++++++++++++++++++- > 1 file changed, 26 insertions(+), 1 deletion(-) > > diff --git a/include/xen/page.h b/include/xen/page.h > index f202992..dac1b26 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 asume that PAGE_SIZE is a multiple of XEN_PAGE_SIZE ^ assume > + * 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 xen_page_to_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(xen_page_to_pfn(page)); > } > > struct xen_memory_region { > -- > 2.1.4 >
On 07/08/15 17:46, Julien Grall wrote: > 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. [...] > +#define xen_page_to_pfn(page) \ > + (((page_to_pfn(page)) << PAGE_SHIFT) >> XEN_PAGE_SHIFT) Rename this to page_to_xen_pfn() David
diff --git a/include/xen/page.h b/include/xen/page.h index f202992..dac1b26 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 asume 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 xen_page_to_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(xen_page_to_pfn(page)); } struct xen_memory_region {