From patchwork Fri May 27 10:06:34 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 9138051 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1D3B16075C for ; Fri, 27 May 2016 10:20:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0F2B32793B for ; Fri, 27 May 2016 10:20:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 03DBC28093; Fri, 27 May 2016 10:20:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 784862793B for ; Fri, 27 May 2016 10:20:22 +0000 (UTC) Received: from localhost ([::1]:45034 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b6EsP-0006lR-EV for patchwork-qemu-devel@patchwork.kernel.org; Fri, 27 May 2016 06:20:21 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35623) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b6Efx-0002uR-FI for qemu-devel@nongnu.org; Fri, 27 May 2016 06:07:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b6Efr-0007Rl-17 for qemu-devel@nongnu.org; Fri, 27 May 2016 06:07:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34551) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b6Efq-0007RZ-RF for qemu-devel@nongnu.org; Fri, 27 May 2016 06:07:22 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 76A82619FF; Fri, 27 May 2016 10:07:22 +0000 (UTC) Received: from donizetti.redhat.com (ovpn-112-66.ams2.redhat.com [10.36.112.66]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u4RA6ise030403; Fri, 27 May 2016 06:07:20 -0400 From: Paolo Bonzini To: qemu-devel@nongnu.org Date: Fri, 27 May 2016 12:06:34 +0200 Message-Id: <1464343604-517-22-git-send-email-pbonzini@redhat.com> In-Reply-To: <1464343604-517-1-git-send-email-pbonzini@redhat.com> References: <1464343604-517-1-git-send-email-pbonzini@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 27 May 2016 10:07:22 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 21/31] xen-hvm: ignore background I/O sections X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Anthony Perard , Paul Durrant , Stefano Stabellini Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Paul Durrant Since Xen will correctly handle accesses to unimplemented I/O ports (by returning all 1's for reads and ignoring writes) there is no need for QEMU to register backgroud I/O sections. This patch therefore adds checks to xen_io_add/del so that sections with memory-region ops pointing at 'unassigned_io_ops' are ignored. Signed-off-by: Paul Durrant Cc: Stefano Stabellini Cc: Anthony Perard Cc: Paolo Bonzini Message-Id: <1462811480-16295-1-git-send-email-paul.durrant@citrix.com> Acked-by: Anthony PERARD Signed-off-by: Paolo Bonzini --- xen-hvm.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/xen-hvm.c b/xen-hvm.c index c14e778..01ee25d 100644 --- a/xen-hvm.c +++ b/xen-hvm.c @@ -511,8 +511,13 @@ static void xen_io_add(MemoryListener *listener, MemoryRegionSection *section) { XenIOState *state = container_of(listener, XenIOState, io_listener); + MemoryRegion *mr = section->mr; - memory_region_ref(section->mr); + if (mr->ops == &unassigned_io_ops) { + return; + } + + memory_region_ref(mr); xen_map_io_section(xen_xc, xen_domid, state->ioservid, section); } @@ -521,10 +526,15 @@ static void xen_io_del(MemoryListener *listener, MemoryRegionSection *section) { XenIOState *state = container_of(listener, XenIOState, io_listener); + MemoryRegion *mr = section->mr; + + if (mr->ops == &unassigned_io_ops) { + return; + } xen_unmap_io_section(xen_xc, xen_domid, state->ioservid, section); - memory_region_unref(section->mr); + memory_region_unref(mr); } static void xen_device_realize(DeviceListener *listener,