From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41EB6C2D0CA for ; Fri, 6 Dec 2019 23:58:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1697720659 for ; Fri, 6 Dec 2019 23:58:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726918AbfLFX6W (ORCPT ); Fri, 6 Dec 2019 18:58:22 -0500 Received: from mga07.intel.com ([134.134.136.100]:55586 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726552AbfLFX5j (ORCPT ); Fri, 6 Dec 2019 18:57:39 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Dec 2019 15:57:37 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,286,1571727600"; d="scan'208";a="219530343" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by fmsmga001.fm.intel.com with ESMTP; 06 Dec 2019 15:57:37 -0800 From: Sean Christopherson To: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 07/16] KVM: x86/mmu: Refactor handling of forced 4k pages in page faults Date: Fri, 6 Dec 2019 15:57:20 -0800 Message-Id: <20191206235729.29263-8-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191206235729.29263-1-sean.j.christopherson@intel.com> References: <20191206235729.29263-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Refactor the page fault handlers and mapping_level() to track the max allowed page level instead of only tracking if a 4k page is mandatory due to one restriction or another. This paves the way for cleanly consolidating tdp_page_fault() and nonpaging_page_fault(), and for eliminating a redundant check on mmu_gfn_lpage_is_disallowed(). No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 45 ++++++++++++++-------------------- arch/x86/kvm/mmu/paging_tmpl.h | 16 +++++++----- 2 files changed, 29 insertions(+), 32 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index bd1711201181..877924cbb75b 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1324,18 +1324,19 @@ gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn, } static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn, - bool *force_pt_level) + int *max_levelp) { - int host_level, max_level; + int host_level, max_level = *max_levelp; struct kvm_memory_slot *slot; - if (unlikely(*force_pt_level)) + if (unlikely(max_level == PT_PAGE_TABLE_LEVEL)) return PT_PAGE_TABLE_LEVEL; slot = kvm_vcpu_gfn_to_memslot(vcpu, large_gfn); - *force_pt_level = !memslot_valid_for_gpte(slot, true); - if (unlikely(*force_pt_level)) + if (!memslot_valid_for_gpte(slot, true)) { + *max_levelp = PT_PAGE_TABLE_LEVEL; return PT_PAGE_TABLE_LEVEL; + } host_level = host_mapping_level(vcpu->kvm, large_gfn); @@ -4169,9 +4170,10 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned long mmu_seq; gfn_t gfn = gpa >> PAGE_SHIFT; bool write = error_code & PFERR_WRITE_MASK; - bool force_pt_level, map_writable; + bool map_writable; bool exec = error_code & PFERR_FETCH_MASK; bool lpage_disallowed = exec && is_nx_huge_page_enabled(); + int max_level; /* Note, paging is disabled, ergo gva == gpa. */ pgprintk("%s: gva %lx error %x\n", __func__, gpa, error_code); @@ -4187,19 +4189,12 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, MMU_WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa)); - force_pt_level = lpage_disallowed; - level = mapping_level(vcpu, gfn, &force_pt_level); - if (likely(!force_pt_level)) { - /* - * This path builds a PAE pagetable - so we can map - * 2mb pages at maximum. Therefore check if the level - * is larger than that. - */ - if (level > PT_DIRECTORY_LEVEL) - level = PT_DIRECTORY_LEVEL; + /* This path builds a PAE pagetable, we can map 2mb pages at maximum. */ + max_level = lpage_disallowed ? PT_PAGE_TABLE_LEVEL : PT_DIRECTORY_LEVEL; + level = mapping_level(vcpu, gfn, &max_level); + if (level > PT_PAGE_TABLE_LEVEL) gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); - } if (fast_page_fault(vcpu, gpa, level, error_code)) return RET_PF_RETRY; @@ -4219,7 +4214,7 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, goto out_unlock; if (make_mmu_pages_available(vcpu) < 0) goto out_unlock; - if (likely(!force_pt_level)) + if (likely(max_level > PT_PAGE_TABLE_LEVEL)) transparent_hugepage_adjust(vcpu, gfn, &pfn, &level); r = __direct_map(vcpu, gpa, write, map_writable, level, pfn, prefault, false); @@ -4273,7 +4268,6 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, kvm_pfn_t pfn; int r; int level; - bool force_pt_level; gfn_t gfn = gpa >> PAGE_SHIFT; unsigned long mmu_seq; int write = error_code & PFERR_WRITE_MASK; @@ -4301,13 +4295,12 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, break; } - force_pt_level = lpage_disallowed || max_level == PT_PAGE_TABLE_LEVEL; - level = mapping_level(vcpu, gfn, &force_pt_level); - if (likely(!force_pt_level)) { - if (level > max_level) - level = max_level; + if (lpage_disallowed) + max_level = PT_PAGE_TABLE_LEVEL; + + level = mapping_level(vcpu, gfn, &max_level); + if (level > PT_PAGE_TABLE_LEVEL) gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); - } if (fast_page_fault(vcpu, gpa, level, error_code)) return RET_PF_RETRY; @@ -4327,7 +4320,7 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, goto out_unlock; if (make_mmu_pages_available(vcpu) < 0) goto out_unlock; - if (likely(!force_pt_level)) + if (likely(max_level > PT_PAGE_TABLE_LEVEL)) transparent_hugepage_adjust(vcpu, gfn, &pfn, &level); r = __direct_map(vcpu, gpa, write, map_writable, level, pfn, prefault, lpage_disallowed); diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index c1d7b866a03f..1938a6e4e631 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -778,7 +778,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code, bool map_writable, is_self_change_mapping; bool lpage_disallowed = (error_code & PFERR_FETCH_MASK) && is_nx_huge_page_enabled(); - bool force_pt_level = lpage_disallowed; + int max_level; pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code); @@ -818,14 +818,18 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code, is_self_change_mapping = FNAME(is_self_change_mapping)(vcpu, &walker, user_fault, &vcpu->arch.write_fault_to_shadow_pgtable); + max_level = lpage_disallowed ? PT_PAGE_TABLE_LEVEL : + PT_MAX_HUGEPAGE_LEVEL; + if (walker.level >= PT_DIRECTORY_LEVEL && !is_self_change_mapping) { - level = mapping_level(vcpu, walker.gfn, &force_pt_level); - if (likely(!force_pt_level)) { + level = mapping_level(vcpu, walker.gfn, &max_level); + if (likely(max_level > PT_DIRECTORY_LEVEL)) { level = min(walker.level, level); walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1); } - } else - force_pt_level = true; + } else { + max_level = PT_PAGE_TABLE_LEVEL; + } mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); @@ -865,7 +869,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code, kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); if (make_mmu_pages_available(vcpu) < 0) goto out_unlock; - if (!force_pt_level) + if (max_level > PT_PAGE_TABLE_LEVEL) transparent_hugepage_adjust(vcpu, walker.gfn, &pfn, &level); r = FNAME(fetch)(vcpu, addr, &walker, write_fault, level, pfn, map_writable, prefault, lpage_disallowed); -- 2.24.0