From patchwork Thu Mar 17 08:37:32 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 8608231 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 550489FD29 for ; Thu, 17 Mar 2016 08:51:12 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 35FB3202E6 for ; Thu, 17 Mar 2016 08:51:11 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0ACF72021A for ; Thu, 17 Mar 2016 08:51:10 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1agTbY-0001E2-UD; Thu, 17 Mar 2016 08:48:28 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1agTbY-0001Dv-DK for xen-devel@lists.xenproject.org; Thu, 17 Mar 2016 08:48:28 +0000 Received: from [85.158.139.211] by server-4.bemta-5.messagelabs.com id DD/24-20731-B5F6AE65; Thu, 17 Mar 2016 08:48:27 +0000 X-Env-Sender: prvs=877c75a5a=Paul.Durrant@citrix.com X-Msg-Ref: server-9.tower-206.messagelabs.com!1458204505!29674497!1 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: 8.11; banners=-,-,- X-VirusChecked: Checked Received: (qmail 64324 invoked from network); 17 Mar 2016 08:48:26 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-9.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2016 08:48:26 -0000 X-IronPort-AV: E=Sophos;i="5.24,349,1454976000"; d="scan'208";a="339798746" From: Paul Durrant To: Date: Thu, 17 Mar 2016 08:37:32 +0000 Message-ID: <1458203853-4441-2-git-send-email-paul.durrant@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1458203853-4441-1-git-send-email-paul.durrant@citrix.com> References: <1458203853-4441-1-git-send-email-paul.durrant@citrix.com> MIME-Version: 1.0 X-DLP: MIA1 Cc: Andrew Cooper , Paul Durrant , Keir Fraser , Jan Beulich Subject: [Xen-devel] [PATCH v4 1/2] x86/hvm/viridian: keep APIC assist page mapped... X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, 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 ... for the lifetime of the domain. If Xen is to make use of the APIC assist enlightenment then a persistent mapping needs to be kept, rather than the temporary one which is currently used only to initialize the page content. This patch also adds a comment block at the top of the source with information on the latest version of the spec. from Microsoft and the current URL where it may be found. Signed-off-by: Paul Durrant Cc: Keir Fraser Cc: Jan Beulich Cc: Andrew Cooper Reviewed-by: Andrew Cooper --- v4: - Added missing teardown required if the MSR is re-written. v2: - Re-instated warning if the initialization of an APIC assist page fails. - Added up-to-date information about the viridian specification to the comment block at the top of the source. --- xen/arch/x86/hvm/hvm.c | 2 + xen/arch/x86/hvm/viridian.c | 77 ++++++++++++++++++++++++++++---------- xen/include/asm-x86/hvm/viridian.h | 8 +++- 3 files changed, 66 insertions(+), 21 deletions(-) diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 4ea51d7..f446ee4 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -2606,6 +2606,8 @@ int hvm_vcpu_initialise(struct vcpu *v) void hvm_vcpu_destroy(struct vcpu *v) { + viridian_vcpu_deinit(v); + hvm_all_ioreq_servers_remove_vcpu(v->domain, v); if ( hvm_altp2m_supported() ) diff --git a/xen/arch/x86/hvm/viridian.c b/xen/arch/x86/hvm/viridian.c index 1ee22aa..b809118 100644 --- a/xen/arch/x86/hvm/viridian.c +++ b/xen/arch/x86/hvm/viridian.c @@ -1,7 +1,12 @@ /****************************************************************************** * viridian.c * - * An implementation of the Viridian hypercall interface. + * An implementation of some Viridian enlightenments. See Microsoft's + * Hypervisor Top Level Functional Specification (v4.0b) at: + * + * https://msdn.microsoft.com/en-us/virtualization/hyperv_on_windows/develop/tlfs + * + * for more information. */ #include @@ -163,7 +168,7 @@ static void dump_apic_assist(const struct vcpu *v) { const union viridian_apic_assist *aa; - aa = &v->arch.hvm_vcpu.viridian.apic_assist; + aa = &v->arch.hvm_vcpu.viridian.apic_assist.msr; printk(XENLOG_G_INFO "%pv: VIRIDIAN APIC_ASSIST: enabled: %x pfn: %lx\n", v, aa->fields.enabled, (unsigned long)aa->fields.pfn); @@ -217,9 +222,9 @@ static void enable_hypercall_page(struct domain *d) static void initialize_apic_assist(struct vcpu *v) { struct domain *d = v->domain; - unsigned long gmfn = v->arch.hvm_vcpu.viridian.apic_assist.fields.pfn; + unsigned long gmfn = v->arch.hvm_vcpu.viridian.apic_assist.msr.fields.pfn; struct page_info *page = get_page_from_gfn(d, gmfn, NULL, P2M_ALLOC); - uint8_t *p; + void *va; /* * We don't yet make use of the APIC assist page but by setting @@ -227,25 +232,49 @@ static void initialize_apic_assist(struct vcpu *v) * bound to support the MSR. We therefore do just enough to keep windows * happy. * - * See http://msdn.microsoft.com/en-us/library/ff538657%28VS.85%29.aspx for - * details of how Windows uses the page. + * See section 13.3.4.1 of the specification for details of this + * enlightenment. */ - if ( !page || !get_page_type(page, PGT_writable_page) ) + if ( !page ) + goto fail; + + if ( !get_page_type(page, PGT_writable_page) ) { - if ( page ) - put_page(page); - gdprintk(XENLOG_WARNING, "Bad GMFN %lx (MFN %lx)\n", gmfn, - page ? page_to_mfn(page) : INVALID_MFN); - return; + put_page(page); + goto fail; } - p = __map_domain_page(page); + va = __map_domain_page_global(page); + if ( !va ) + { + put_page_and_type(page); + goto fail; + } - *(u32 *)p = 0; + *(uint32_t *)va = 0; - unmap_domain_page(p); + v->arch.hvm_vcpu.viridian.apic_assist.page = page; + v->arch.hvm_vcpu.viridian.apic_assist.va = va; + return; + + fail: + gdprintk(XENLOG_WARNING, "Bad GMFN %lx (MFN %lx)\n", gmfn, + page ? page_to_mfn(page) : INVALID_MFN); +} + +static void teardown_apic_assist(struct vcpu *v) +{ + struct page_info *page = v->arch.hvm_vcpu.viridian.apic_assist.page; + void *va = v->arch.hvm_vcpu.viridian.apic_assist.va; + if ( !va ) + return; + + v->arch.hvm_vcpu.viridian.apic_assist.va = NULL; + v->arch.hvm_vcpu.viridian.apic_assist.page = NULL; + + unmap_domain_page_global(va); put_page_and_type(page); } @@ -374,9 +403,10 @@ int wrmsr_viridian_regs(uint32_t idx, uint64_t val) case VIRIDIAN_MSR_APIC_ASSIST: perfc_incr(mshv_wrmsr_apic_msr); - v->arch.hvm_vcpu.viridian.apic_assist.raw = val; + teardown_apic_assist(v); /* release any previous mapping */ + v->arch.hvm_vcpu.viridian.apic_assist.msr.raw = val; dump_apic_assist(v); - if (v->arch.hvm_vcpu.viridian.apic_assist.fields.enabled) + if ( v->arch.hvm_vcpu.viridian.apic_assist.msr.fields.enabled ) initialize_apic_assist(v); break; @@ -485,7 +515,7 @@ int rdmsr_viridian_regs(uint32_t idx, uint64_t *val) case VIRIDIAN_MSR_APIC_ASSIST: perfc_incr(mshv_rdmsr_apic_msr); - *val = v->arch.hvm_vcpu.viridian.apic_assist.raw; + *val = v->arch.hvm_vcpu.viridian.apic_assist.msr.raw; break; case VIRIDIAN_MSR_REFERENCE_TSC: @@ -521,6 +551,11 @@ int rdmsr_viridian_regs(uint32_t idx, uint64_t *val) return 1; } +void viridian_vcpu_deinit(struct vcpu *v) +{ + teardown_apic_assist(v); +} + static DEFINE_PER_CPU(cpumask_t, ipi_cpumask); int viridian_hypercall(struct cpu_user_regs *regs) @@ -721,7 +756,7 @@ static int viridian_save_vcpu_ctxt(struct domain *d, hvm_domain_context_t *h) for_each_vcpu( d, v ) { struct hvm_viridian_vcpu_context ctxt; - ctxt.apic_assist = v->arch.hvm_vcpu.viridian.apic_assist.raw; + ctxt.apic_assist = v->arch.hvm_vcpu.viridian.apic_assist.msr.raw; if ( hvm_save_entry(VIRIDIAN_VCPU, v->vcpu_id, h, &ctxt) != 0 ) return 1; @@ -747,7 +782,9 @@ static int viridian_load_vcpu_ctxt(struct domain *d, hvm_domain_context_t *h) if ( hvm_load_entry(VIRIDIAN_VCPU, h, &ctxt) != 0 ) return -EINVAL; - v->arch.hvm_vcpu.viridian.apic_assist.raw = ctxt.apic_assist; + v->arch.hvm_vcpu.viridian.apic_assist.msr.raw = ctxt.apic_assist; + if ( v->arch.hvm_vcpu.viridian.apic_assist.msr.fields.enabled ) + initialize_apic_assist(v); return 0; } diff --git a/xen/include/asm-x86/hvm/viridian.h b/xen/include/asm-x86/hvm/viridian.h index c4319d7..ee3a120 100644 --- a/xen/include/asm-x86/hvm/viridian.h +++ b/xen/include/asm-x86/hvm/viridian.h @@ -21,7 +21,11 @@ union viridian_apic_assist struct viridian_vcpu { - union viridian_apic_assist apic_assist; + struct { + union viridian_apic_assist msr; + struct page_info *page; + void *va; + } apic_assist; }; union viridian_guest_os_id @@ -117,6 +121,8 @@ viridian_hypercall(struct cpu_user_regs *regs); void viridian_time_ref_count_freeze(struct domain *d); void viridian_time_ref_count_thaw(struct domain *d); +void viridian_vcpu_deinit(struct vcpu *v); + #endif /* __ASM_X86_HVM_VIRIDIAN_H__ */ /*