Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752496Ab3JWRRD (ORCPT ); Wed, 23 Oct 2013 13:17:03 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:61240 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751208Ab3JWRRA (ORCPT ); Wed, 23 Oct 2013 13:17:00 -0400 X-IronPort-AV: E=Sophos;i="4.93,555,1378857600"; d="scan'208";a="63919454" Date: Wed, 23 Oct 2013 18:15:56 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: Stefano Stabellini , , , , Subject: Re: [PATCH v8 17/19] grant-table: call set_phys_to_machine after mapping grant refs In-Reply-To: <20131023140457.GC27771@phenom.dumpdata.com> Message-ID: References: <1382031814-8782-17-git-send-email-stefano.stabellini@eu.citrix.com> <20131023140457.GC27771@phenom.dumpdata.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2812 Lines: 79 On Wed, 23 Oct 2013, Konrad Rzeszutek Wilk wrote: > On Thu, Oct 17, 2013 at 06:43:32PM +0100, Stefano Stabellini wrote: > > When mapping/unmapping grant refs, call > > set_phys_to_machine to update the P2M with the new mappings for > > autotranslate guests. > > Heh. That sounds so odd (p2m + xlat). > Can you add a sentence saying that this is a mostly a nop on x86 please? > > (Well, the call to set_phys_to_machine does end up with this check: > > if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) { > BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); > return true; > } > But that should be a fairly small amount of code. > Sure, I'll add a comment. > > > > Signed-off-by: Stefano Stabellini > > --- > > drivers/xen/grant-table.c | 17 +++++++++++++++-- > > 1 files changed, 15 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c > > index 04cdeb8..a36cb03 100644 > > --- a/drivers/xen/grant-table.c > > +++ b/drivers/xen/grant-table.c > > @@ -49,6 +49,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > > > @@ -889,8 +890,15 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, > > gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, map_ops + i, > > &map_ops[i].status, __func__); > > > > - if (xen_feature(XENFEAT_auto_translated_physmap)) > > + if (xen_feature(XENFEAT_auto_translated_physmap)) { > > + for (i = 0; i < count; i++) { > > + if (map_ops[i].status) > > + continue; > > + set_phys_to_machine(map_ops[i].host_addr >> PAGE_SHIFT, > > + map_ops[i].dev_bus_addr >> PAGE_SHIFT); > > + } > > return ret; > > + } > > > > if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) { > > arch_enter_lazy_mmu_mode(); > > @@ -933,8 +941,13 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, > > if (ret) > > return ret; > > > > - if (xen_feature(XENFEAT_auto_translated_physmap)) > > + if (xen_feature(XENFEAT_auto_translated_physmap)) { > > + for (i = 0; i < count; i++) { > > + set_phys_to_machine(unmap_ops[i].host_addr >> PAGE_SHIFT, > > + INVALID_P2M_ENTRY); > > + } > > return ret; > > + } > > > > if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) { > > arch_enter_lazy_mmu_mode(); > > -- > > 1.7.2.5 > > > -- 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/