From patchwork Tue Jan 26 15:52:03 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 8124411 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 906E79F818 for ; Tue, 26 Jan 2016 15:54:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9A8B92025B for ; Tue, 26 Jan 2016 15:54:46 +0000 (UTC) Received: from lists.xen.org (lists.xenproject.org [50.57.142.19]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 853832025A for ; Tue, 26 Jan 2016 15:54:45 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aO5vD-0000QD-F4; Tue, 26 Jan 2016 15:52:47 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aO5vB-0000Nh-C6 for xen-devel@lists.xensource.com; Tue, 26 Jan 2016 15:52:45 +0000 Received: from [85.158.139.211] by server-4.bemta-5.messagelabs.com id 03/3E-12635-C4697A65; Tue, 26 Jan 2016 15:52:44 +0000 X-Env-Sender: prvs=826ae1113=Stefano.Stabellini@citrix.com X-Msg-Ref: server-16.tower-206.messagelabs.com!1453823560!17958194!3 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 7.35.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 36678 invoked from network); 26 Jan 2016 15:52:43 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-16.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 26 Jan 2016 15:52:43 -0000 X-IronPort-AV: E=Sophos;i="5.22,350,1449532800"; d="scan'208";a="327722915" From: Stefano Stabellini To: Date: Tue, 26 Jan 2016 15:52:03 +0000 Message-ID: <1453823527-22312-4-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: MIME-Version: 1.0 X-DLP: MIA1 Cc: Ian Campbell , xen-devel@lists.xensource.com, qemu-devel@nongnu.org, Stefano Stabellini Subject: [Xen-devel] [PULL 4/8] xen: Switch uses of xc_map_foreign_range into xc_map_foreign_pages X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Ian Campbell In Xen 4.7 we are refactoring parts libxenctrl into a number of separate libraries which will provide backward and forward API and ABI compatiblity. One such library will be libxenforeignmemory which provides access to privileged foreign mappings and which will provide an interface equivalent to xc_map_foreign_{pages,bulk}. In preparation for this switch all uses of xc_map_foreign_range to xc_map_foreign_pages. This is trivial because size was always XC_PAGE_SIZE so the necessary adjustments are trivial: * Pass &mfn (an array of length 1) instead of mfn. The function takes a pointer to const, so there is no possibily of mfn changing due to this change. * Pass nr_pages=1 instead of size=XC_PAGE_SIZE There is one wrinkle in xen_console.c:con_initialise() where con->ring_ref is an int but can in some code paths (when !xendev->dev) be treated as an mfn. I think this is an existing latent truncation hazard on platforms where xen_pfn_t is 64-bit and int is 32-bit (e.g. amd64, both arm* variants). I'm unsure under what circumstances xendev->dev can be NULL or if anything elsewhere ensures the value fits into an int. For now I just use a temporary xen_pfn_t to in effect upcast the pointer from int* to xen_pfn_t*. In xenfb.c:common_bind we now explicitly launder the mfn into a xen_pfn_t, so it has the correct type to be passed to xc_map_foreign_pages and doesn't provoke warnings on 32-bit x86. Signed-off-by: Ian Campbell Reviewed-by: Stefano Stabellini --- hw/char/xen_console.c | 8 ++++---- hw/display/xenfb.c | 15 ++++++++------- xen-hvm.c | 14 +++++++------- 3 files changed, 19 insertions(+), 18 deletions(-) diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c index ac1b324..3e8a57b 100644 --- a/hw/char/xen_console.c +++ b/hw/char/xen_console.c @@ -228,10 +228,10 @@ static int con_initialise(struct XenDevice *xendev) con->buffer.max_capacity = limit; if (!xendev->dev) { - con->sring = xc_map_foreign_range(xen_xc, con->xendev.dom, - XC_PAGE_SIZE, - PROT_READ|PROT_WRITE, - con->ring_ref); + xen_pfn_t mfn = con->ring_ref; + con->sring = xc_map_foreign_pages(xen_xc, con->xendev.dom, + PROT_READ|PROT_WRITE, + &mfn, 1); } else { con->sring = xengnttab_map_grant_ref(xendev->gnttabdev, con->xendev.dom, con->ring_ref, diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c index 8eb3046..aa38803 100644 --- a/hw/display/xenfb.c +++ b/hw/display/xenfb.c @@ -95,23 +95,24 @@ struct XenFB { static int common_bind(struct common *c) { - uint64_t mfn; + uint64_t val; + xen_pfn_t mfn; - if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &mfn) == -1) + if (xenstore_read_fe_uint64(&c->xendev, "page-ref", &val) == -1) return -1; - assert(mfn == (xen_pfn_t)mfn); + mfn = (xen_pfn_t)val; + assert(val == mfn); if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1) return -1; - c->page = xc_map_foreign_range(xen_xc, c->xendev.dom, - XC_PAGE_SIZE, - PROT_READ | PROT_WRITE, mfn); + c->page = xc_map_foreign_pages(xen_xc, c->xendev.dom, + PROT_READ | PROT_WRITE, &mfn, 1); if (c->page == NULL) return -1; xen_be_bind_evtchn(&c->xendev); - xen_be_printf(&c->xendev, 1, "ring mfn %"PRIx64", remote-port %d, local-port %d\n", + xen_be_printf(&c->xendev, 1, "ring mfn %"PRI_xen_pfn", remote-port %d, local-port %d\n", mfn, c->xendev.remote_port, c->xendev.local_port); return 0; diff --git a/xen-hvm.c b/xen-hvm.c index 1b6fa9e..878ae0a 100644 --- a/xen-hvm.c +++ b/xen-hvm.c @@ -1242,8 +1242,9 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory) DPRINTF("buffered io page at pfn %lx\n", bufioreq_pfn); DPRINTF("buffered io evtchn is %x\n", bufioreq_evtchn); - state->shared_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE, - PROT_READ|PROT_WRITE, ioreq_pfn); + state->shared_page = xc_map_foreign_pages(xen_xc, xen_domid, + PROT_READ|PROT_WRITE, + &ioreq_pfn, 1); if (state->shared_page == NULL) { error_report("map shared IO page returned error %d handle=" XC_INTERFACE_FMT, errno, xen_xc); @@ -1254,8 +1255,8 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory) if (!rc) { DPRINTF("shared vmport page at pfn %lx\n", ioreq_pfn); state->shared_vmport_page = - xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE, - PROT_READ|PROT_WRITE, ioreq_pfn); + xc_map_foreign_pages(xen_xc, xen_domid, PROT_READ|PROT_WRITE, + &ioreq_pfn, 1); if (state->shared_vmport_page == NULL) { error_report("map shared vmport IO page returned error %d handle=" XC_INTERFACE_FMT, errno, xen_xc); @@ -1267,10 +1268,9 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory) goto err; } - state->buffered_io_page = xc_map_foreign_range(xen_xc, xen_domid, - XC_PAGE_SIZE, + state->buffered_io_page = xc_map_foreign_pages(xen_xc, xen_domid, PROT_READ|PROT_WRITE, - bufioreq_pfn); + &bufioreq_pfn, 1); if (state->buffered_io_page == NULL) { error_report("map buffered IO page returned error %d", errno); goto err;