Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935207AbbHJKsF (ORCPT ); Mon, 10 Aug 2015 06:48:05 -0400 Received: from smtp.citrix.com ([66.165.176.89]:17579 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932716AbbHJKsC (ORCPT ); Mon, 10 Aug 2015 06:48:02 -0400 X-IronPort-AV: E=Sophos;i="5.15,644,1432598400"; d="scan'208";a="289598534" Date: Mon, 10 Aug 2015 11:46:33 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Julien Grall CC: , , , , , Konrad Rzeszutek Wilk , Boris Ostrovsky , "David Vrabel" Subject: Re: [PATCH v3 03/20] xen: Add Xen specific page definition In-Reply-To: <1438966019-19322-4-git-send-email-julien.grall@citrix.com> Message-ID: References: <1438966019-19322-1-git-send-email-julien.grall@citrix.com> <1438966019-19322-4-git-send-email-julien.grall@citrix.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-DLP: MIA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2976 Lines: 88 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 > Reviewed-by: Stefano Stabellini > > --- > Cc: Konrad Rzeszutek Wilk > Cc: Boris Ostrovsky > Cc: David Vrabel > > 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 > + > +/* 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 > > +/* 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 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/