From patchwork Fri Apr 1 17:55:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Matlack X-Patchwork-Id: 12798533 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6A80C4167B for ; Fri, 1 Apr 2022 17:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350640AbiDAR6C (ORCPT ); Fri, 1 Apr 2022 13:58:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350630AbiDAR6B (ORCPT ); Fri, 1 Apr 2022 13:58:01 -0400 Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 91A4AC4E2A for ; Fri, 1 Apr 2022 10:56:11 -0700 (PDT) Received: by mail-pl1-x649.google.com with SMTP id h6-20020a170902f54600b001567317c144so106652plf.14 for ; Fri, 01 Apr 2022 10:56:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=IyIPSk2/EaBUB0UobyNpb06WjR6I1O9i3ZizvW3fhmY=; b=diK+NDVVMnH1euNmcgNZkZR+RNe+RtbEPnphRRHdwnohQBdcNG3DKV2+OalZZ9dtiO 4U1BmQRB9ltXsq1iribzjEnPiYHQfyjaB/RIv7u3RQME2nqt4UISDss9FwhaKRI73n2M bMU+zTqvPQzdMjCfjifjO/HgM4CjFbg0oko4cVui9/LHWSrFQKcR1tLhe7lbcKG+MY6Q lj9/alcDyXKJ/nW3dpp0m5fF9issvOVGtIPN401aoBG2OVH4cv2Xqlye/tg/RF+3/hn7 WxjoFGMkrlclU9nEnzQJ5GSO36yNskFztCeAocXYe1LYhR2jSCTTrWpJUtyLXPUObvDR s/ig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=IyIPSk2/EaBUB0UobyNpb06WjR6I1O9i3ZizvW3fhmY=; b=YgKHIr5PpQveliscxwd8M1wnbMEQ8HMeDD/qhcCuVmo+K4GJH8EpUjFA1CEXC2QR3G Ss8oPHPQK/p/Yk1cxiBPg9DU+hxR9hysej83eiuzcO9N5LB4TsBDaFhICwNTJNK3BDUj nRCZAeDy0gQy9CKuAf43NHD/TxDG469dox1h24js52JYdpo8IsX5ATwXbRIPME4fH8f+ sQegHMHJpgFOlgSi0ndh+rimnvXztTssmYveYRWwgSTh1kuxLZkhcgX6s8n0Pcq0ViYX Na/qfk84OtiLmyNdMKrmHPFSeO0rriO5DrHkMDg2H+DhWjmNLlqPqnHWgcRGVbWRFi16 0fRA== X-Gm-Message-State: AOAM530+eeXxM0tw+Kd6gNnZ1m8WFiInRrpHvo9ONiX1GmzHRbRuEnfk 9mcgxplI3OceDbgI4FHwmArz2SBWQ8PI5Q== X-Google-Smtp-Source: ABdhPJw+3njlRranWemDGRAFfxcGs6Z7lxR+Q6odwZANW7lQMpZ7k6xIEK9JVJtusBFO1h+uHnsiH7sfkuQYbQ== X-Received: from dmatlack-heavy.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:19cd]) (user=dmatlack job=sendgmr) by 2002:a05:6a00:2d0:b0:4f4:1f34:e39d with SMTP id b16-20020a056a0002d000b004f41f34e39dmr12123192pft.14.1648835771030; Fri, 01 Apr 2022 10:56:11 -0700 (PDT) Date: Fri, 1 Apr 2022 17:55:37 +0000 In-Reply-To: <20220401175554.1931568-1-dmatlack@google.com> Message-Id: <20220401175554.1931568-7-dmatlack@google.com> Mime-Version: 1.0 References: <20220401175554.1931568-1-dmatlack@google.com> X-Mailer: git-send-email 2.35.1.1094.g7c7d902a7c-goog Subject: [PATCH v3 06/23] KVM: x86/mmu: Pass memslot to kvm_mmu_new_shadow_page() From: David Matlack To: Paolo Bonzini Cc: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Sean Christopherson , Andrew Jones , Ben Gardon , Peter Xu , maciej.szmigiero@oracle.com, "moderated list:KERNEL VIRTUAL MACHINE FOR ARM64 (KVM/arm64)" , "open list:KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)" , "open list:KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)" , "open list:KERNEL VIRTUAL MACHINE FOR RISC-V (KVM/riscv)" , Peter Feiner , David Matlack Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Passing the memslot to kvm_mmu_new_shadow_page() avoids the need for the vCPU pointer when write-protecting indirect 4k shadow pages. This moves us closer to being able to create new shadow pages during VM ioctls for eager page splitting, where there is not vCPU pointer. This change does not negatively impact "Populate memory time" for ept=Y or ept=N configurations since kvm_vcpu_gfn_to_memslot() caches the last use slot. So even though we now look up the slot more often, it is a very cheap check. Opportunistically move the code to write-protect GFNs shadowed by PG_LEVEL_4K shadow pages into account_shadowed() to reduce indentation and consolidate the code. This also eliminates a memslot lookup. No functional change intended. Reviewed-by: Peter Xu Signed-off-by: David Matlack --- arch/x86/kvm/mmu/mmu.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index dc1825de0752..abfb3e5d1372 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -793,16 +793,14 @@ void kvm_mmu_gfn_allow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn) update_gfn_disallow_lpage_count(slot, gfn, -1); } -static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) +static void account_shadowed(struct kvm *kvm, + struct kvm_memory_slot *slot, + struct kvm_mmu_page *sp) { - struct kvm_memslots *slots; - struct kvm_memory_slot *slot; gfn_t gfn; kvm->arch.indirect_shadow_pages++; gfn = sp->gfn; - slots = kvm_memslots_for_spte_role(kvm, sp->role); - slot = __gfn_to_memslot(slots, gfn); /* the non-leaf shadow pages are keeping readonly. */ if (sp->role.level > PG_LEVEL_4K) @@ -810,6 +808,9 @@ static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) KVM_PAGE_TRACK_WRITE); kvm_mmu_gfn_disallow_lpage(slot, gfn); + + if (kvm_mmu_slot_gfn_write_protect(kvm, slot, gfn, PG_LEVEL_4K)) + kvm_flush_remote_tlbs_with_address(kvm, gfn, 1); } void account_huge_nx_page(struct kvm *kvm, struct kvm_mmu_page *sp) @@ -2123,6 +2124,7 @@ static struct kvm_mmu_page *kvm_mmu_find_shadow_page(struct kvm_vcpu *vcpu, } static struct kvm_mmu_page *kvm_mmu_new_shadow_page(struct kvm_vcpu *vcpu, + struct kvm_memory_slot *slot, gfn_t gfn, union kvm_mmu_page_role role) { @@ -2138,11 +2140,8 @@ static struct kvm_mmu_page *kvm_mmu_new_shadow_page(struct kvm_vcpu *vcpu, sp_list = &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]; hlist_add_head(&sp->hash_link, sp_list); - if (!role.direct) { - account_shadowed(vcpu->kvm, sp); - if (role.level == PG_LEVEL_4K && kvm_vcpu_write_protect_gfn(vcpu, gfn)) - kvm_flush_remote_tlbs_with_address(vcpu->kvm, gfn, 1); - } + if (!role.direct) + account_shadowed(vcpu->kvm, slot, sp); return sp; } @@ -2151,13 +2150,15 @@ static struct kvm_mmu_page *kvm_mmu_get_shadow_page(struct kvm_vcpu *vcpu, gfn_t gfn, union kvm_mmu_page_role role) { + struct kvm_memory_slot *slot; struct kvm_mmu_page *sp; bool created = false; sp = kvm_mmu_find_shadow_page(vcpu, gfn, role); if (!sp) { created = true; - sp = kvm_mmu_new_shadow_page(vcpu, gfn, role); + slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); + sp = kvm_mmu_new_shadow_page(vcpu, slot, gfn, role); } trace_kvm_mmu_get_page(sp, created);