From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752074Ab2G0NsP (ORCPT ); Fri, 27 Jul 2012 09:48:15 -0400 Received: from smtp.eu.citrix.com ([62.200.22.115]:27095 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751053Ab2G0NsN (ORCPT ); Fri, 27 Jul 2012 09:48:13 -0400 X-IronPort-AV: E=Sophos;i="4.77,667,1336348800"; d="scan'208";a="13735994" Date: Fri, 27 Jul 2012 14:47:18 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: Stefano Stabellini , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xensource.com" , "linaro-dev@lists.linaro.org" , Ian Campbell , "arnd@arndb.de" , "catalin.marinas@arm.com" , "Tim (Xen.org)" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [Xen-devel] [PATCH 03/24] xen/arm: page.h definitions In-Reply-To: <20120726163655.GD9222@phenom.dumpdata.com> Message-ID: References: <1343316846-25860-3-git-send-email-stefano.stabellini@eu.citrix.com> <20120726163655.GD9222@phenom.dumpdata.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 26 Jul 2012, Konrad Rzeszutek Wilk wrote: > On Thu, Jul 26, 2012 at 04:33:45PM +0100, Stefano Stabellini wrote: > > ARM Xen guests always use paging in hardware, like PV on HVM guests in > > the X86 world. > > Nice, so no dealing with the P2M at all in the guest? Nope ;-) > > Signed-off-by: Stefano Stabellini > > --- > > arch/arm/include/asm/xen/page.h | 77 +++++++++++++++++++++++++++++++++++++++ > > 1 files changed, 77 insertions(+), 0 deletions(-) > > create mode 100644 arch/arm/include/asm/xen/page.h > > > > diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h > > new file mode 100644 > > index 0000000..6cfe9a1 > > --- /dev/null > > +++ b/arch/arm/include/asm/xen/page.h > > @@ -0,0 +1,77 @@ > > +#ifndef _ASM_ARM_XEN_PAGE_H > > +#define _ASM_ARM_XEN_PAGE_H > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > I don't if it makes such a difference, but putting the headers in sorted > order is sometimes nicer than just randomly.. But that might be just > me liking an orderly world nowadays :-) I can do that > > + > > +#define pfn_to_mfn(pfn) (pfn) > > +#define phys_to_machine_mapping_valid (1) > > +#define mfn_to_pfn(mfn) (mfn) > > +#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) > > + > > +#define pte_mfn pte_pfn > > +#define mfn_pte pfn_pte > > + > > +/* Xen machine address */ > > +typedef struct xmaddr { > > + phys_addr_t maddr; > > +} xmaddr_t; > > + > > +/* Xen pseudo-physical address */ > > +typedef struct xpaddr { > > + phys_addr_t paddr; > > +} xpaddr_t; > > + > > +#define XMADDR(x) ((xmaddr_t) { .maddr = (x) }) > > +#define XPADDR(x) ((xpaddr_t) { .paddr = (x) }) > > + > > +static inline xmaddr_t phys_to_machine(xpaddr_t phys) > > +{ > > + unsigned offset = phys.paddr & ~PAGE_MASK; > > + return XMADDR(PFN_PHYS(pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset); > > +} > > + > > +static inline xpaddr_t machine_to_phys(xmaddr_t machine) > > +{ > > + unsigned offset = machine.maddr & ~PAGE_MASK; > > + return XPADDR(PFN_PHYS(mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset); > > +} > > +/* VIRT <-> MACHINE conversion */ > > +#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) > > +#define virt_to_pfn(v) (PFN_DOWN(__pa(v))) > > +#define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v))) > > +#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) > > + > > +static inline xmaddr_t arbitrary_virt_to_machine(void *vaddr) > > +{ > > + /* XXX: assuming it is mapped in the kernel 1:1 */ > > + return virt_to_machine(vaddr); > > +} > > + > > +/* XXX: this shouldn't be here */ > > So why is it here? lookup_address shouldn't be here because it is an x86-only interface. However both gntdev.c and xenbus_client.c call it (in PV only code paths that are never taken in a PV on HVM guest), so in order to compile them I have to define lookup_address. > > +static inline pte_t *lookup_address(unsigned long address, unsigned int *level) > > +{ > > + BUG(); > > + return NULL; > > +} > > + > > +static inline int m2p_add_override(unsigned long mfn, struct page *page, > > + struct gnttab_map_grant_ref *kmap_op) > > +{ > > + return 0; > > +} > > + > > +static inline int m2p_remove_override(struct page *page, bool clear_pte) > > +{ > > + return 0; > > +} > > + > > +static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn) > > +{ > > + BUG(); > > + return false; > > +} > > +#endif /* _ASM_ARM_XEN_PAGE_H */