From patchwork Thu Oct 10 18:23:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 13831166 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8AEE9D24456 for ; Thu, 10 Oct 2024 21:16:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:Reply-To:List-Subscribe:List-Help: List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:Message-ID :References:Mime-Version:In-Reply-To:Date:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jj2wNaAxCcma+QiviSUbMtgXcol+ckaAW+fieRepz8s=; b=MLD/Q0z+bPSZ0y 3VNS0Nd3aH1jOFlpjCuUsCKGyH+6LY8YkIIg7Sf94aNvTZEbJla6Opwpr10O6GnjqWn+lVdfuLA42 8wfkZZQOODX6ia/u8m34i0xKDWmnqyugbUJAUwqpnDHxfmxIJXjNzs9XwD0E/CmofO36Vxyln7W2w zCXwrymQh09FGWRUPjwPc+wIXAUBiTdsoUwWIlp75rssbtkcu2uKzI59F3EqA1uahehQaQEdIdsRX adSlv4lnxsaSP5vk2tNC5gTvVdwli8pdwzrxHvDcH3yRSX2jYvt23v8KK5rUJNamSG8NjTv4H0pv+ RnaUoCKOtUkdQelXrj1g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1sz0WO-0000000ENa8-13lY; Thu, 10 Oct 2024 21:16:32 +0000 Received: from mail-yw1-x1149.google.com ([2607:f8b0:4864:20::1149]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1syxrO-0000000DqVK-1rip for linux-riscv@lists.infradead.org; Thu, 10 Oct 2024 18:26:04 +0000 Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-6e3204db795so21454187b3.2 for ; Thu, 10 Oct 2024 11:26:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1728584761; x=1729189561; darn=lists.infradead.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:reply-to:from:to:cc:subject:date :message-id:reply-to; bh=+DlXoUFYFzJpPJut8ySNZ/avzuJs4Hk+oSmN6VTWgSk=; b=4EMLSx3Ftaw9gpvv4YrUXwm4Ks7qKUIi5Av2oi+legj4y7IQEeq9x4wlwZS+YWWx8t 0xit1JXqyQbkuGjTIvQTmIh9VVxkJnzZXwCY7NnCxL7Tzx0AQ0WqR/rS8TtjzL7zlSar vqNLhoD9LADMuTHQFqSPrwSjvccSQtNnO1Ox0zkU50RacgMm0RN7WZ6nwppBMtVycT3Q 5VtuL7yKy6hZPQuGehnhFA4hxkc7QeNABSIZ4rdhaX3h1YQOLR+4r+p6RuoQu94V8inI q5M+hfNWjQ/vrjfsKEFYLuelSGw5zlEhMvv7lcNZQL9Y3xwO0lH2zxpMwHOTTMe7gdJJ bUiw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728584761; x=1729189561; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:reply-to:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=+DlXoUFYFzJpPJut8ySNZ/avzuJs4Hk+oSmN6VTWgSk=; b=lxc2dSgcPtsC+k4AuAR1c6Fsv5u1E4J/Z+NSYbrGK0IKyrL9xGfqmujmtLu1VY5Een GTUyMfRk7v5WMOOENO5wUIeFCIO+CbuT90253oWO5BIyC/euWggFgCyXIrObrGy2Mh64 tigwhvErWfPqBUXiQtN/JD2LxocZrx9rnPzCS/S5U5DuhApNanKxDYGiEBkkZ8mk2rhM Ecwyxs5AA60rJLuzP0IR/OOn2GJA6bz8Pd6TwY5hVeEgxicirNGYNAIMIE3kkBIvoiHn ArSvOJPoG/eqiipHCnEJ+gZSq9MPZW4VeGklOQ67U+HyDcZwamTqPDHfiKK345RCSL6D /BEg== X-Forwarded-Encrypted: i=1; AJvYcCXLreD6SRGvKxqwRDe6w4MGCjNNvIyqJvw0U3YqtgrW9W8hSaIZeXgLjmmO9LUPN4wcOv1xhL/wiPSY/w==@lists.infradead.org X-Gm-Message-State: AOJu0YyUtQT34EJl8ncbm9RO2+bFJ7zT6xNY+PZSCVqv9V1JBWLXeF6c KNOulTxJ+/bA84uT7rS8FHg/BCunpxJdzOscT+/wShJ1CAe3R0oTtULN3BuHhMc5wKt9vyYxadS AbQ== X-Google-Smtp-Source: AGHT+IHYBe/gylmYYB76Y4JbCGQqBxyU7NvKFk8CzbtQRqqOSH0kk5njqmBLFW7wxt+Okx9MKc9CHg/F7Og= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:9d:3983:ac13:c240]) (user=seanjc job=sendgmr) by 2002:a05:690c:4349:b0:6e2:1713:bdb5 with SMTP id 00721157ae682-6e32217cfd3mr118607b3.5.1728584760829; Thu, 10 Oct 2024 11:26:00 -0700 (PDT) Date: Thu, 10 Oct 2024 11:23:35 -0700 In-Reply-To: <20241010182427.1434605-1-seanjc@google.com> Mime-Version: 1.0 References: <20241010182427.1434605-1-seanjc@google.com> X-Mailer: git-send-email 2.47.0.rc1.288.g06298d1525-goog Message-ID: <20241010182427.1434605-34-seanjc@google.com> Subject: [PATCH v13 33/85] KVM: Pass in write/dirty to kvm_vcpu_map(), not kvm_vcpu_unmap() From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Sean Christopherson Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, " =?utf-8?q?Alex_Benn=C3=A9e?= " , Yan Zhao , David Matlack , David Stevens , Andrew Jones X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241010_112602_571719_09F4B34F X-CRM114-Status: GOOD ( 16.44 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Sean Christopherson Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Now that all kvm_vcpu_{,un}map() users pass "true" for @dirty, have them pass "true" as a @writable param to kvm_vcpu_map(), and thus create a read-only mapping when possible. Note, creating read-only mappings can be theoretically slower, as they don't play nice with fast GUP due to the need to break CoW before mapping the underlying PFN. But practically speaking, creating a mapping isn't a super hot path, and getting a writable mapping for reading is weird and confusing. Tested-by: Alex Bennée Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/nested.c | 4 ++-- arch/x86/kvm/svm/sev.c | 2 +- arch/x86/kvm/svm/svm.c | 8 ++++---- arch/x86/kvm/vmx/nested.c | 16 ++++++++-------- include/linux/kvm_host.h | 20 ++++++++++++++++++-- virt/kvm/kvm_main.c | 12 +++++++----- 6 files changed, 40 insertions(+), 22 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index d5314cb7dff4..9f9478bdecfc 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -922,7 +922,7 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu) nested_svm_vmexit(svm); out: - kvm_vcpu_unmap(vcpu, &map, true); + kvm_vcpu_unmap(vcpu, &map); return ret; } @@ -1126,7 +1126,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm) vmcb12->control.exit_int_info_err, KVM_ISA_SVM); - kvm_vcpu_unmap(vcpu, &map, true); + kvm_vcpu_unmap(vcpu, &map); nested_svm_transition_tlb_flush(vcpu); diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 0b851ef937f2..4557ff3804ae 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -3468,7 +3468,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm) sev_es_sync_to_ghcb(svm); - kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map, true); + kvm_vcpu_unmap(&svm->vcpu, &svm->sev_es.ghcb_map); svm->sev_es.ghcb = NULL; } diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 9df3e1e5ae81..c1e29307826b 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2299,7 +2299,7 @@ static int vmload_vmsave_interception(struct kvm_vcpu *vcpu, bool vmload) svm_copy_vmloadsave_state(vmcb12, svm->vmcb); } - kvm_vcpu_unmap(vcpu, &map, true); + kvm_vcpu_unmap(vcpu, &map); return ret; } @@ -4714,7 +4714,7 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram) svm_copy_vmrun_state(map_save.hva + 0x400, &svm->vmcb01.ptr->save); - kvm_vcpu_unmap(vcpu, &map_save, true); + kvm_vcpu_unmap(vcpu, &map_save); return 0; } @@ -4774,9 +4774,9 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram) svm->nested.nested_run_pending = 1; unmap_save: - kvm_vcpu_unmap(vcpu, &map_save, true); + kvm_vcpu_unmap(vcpu, &map_save); unmap_map: - kvm_vcpu_unmap(vcpu, &map, true); + kvm_vcpu_unmap(vcpu, &map); return ret; } diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index ff83b56fe2fa..259fe445e695 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -231,7 +231,7 @@ static inline void nested_release_evmcs(struct kvm_vcpu *vcpu) struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); struct vcpu_vmx *vmx = to_vmx(vcpu); - kvm_vcpu_unmap(vcpu, &vmx->nested.hv_evmcs_map, true); + kvm_vcpu_unmap(vcpu, &vmx->nested.hv_evmcs_map); vmx->nested.hv_evmcs = NULL; vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID; @@ -318,9 +318,9 @@ static void nested_put_vmcs12_pages(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); - kvm_vcpu_unmap(vcpu, &vmx->nested.apic_access_page_map, true); - kvm_vcpu_unmap(vcpu, &vmx->nested.virtual_apic_map, true); - kvm_vcpu_unmap(vcpu, &vmx->nested.pi_desc_map, true); + kvm_vcpu_unmap(vcpu, &vmx->nested.apic_access_page_map); + kvm_vcpu_unmap(vcpu, &vmx->nested.virtual_apic_map); + kvm_vcpu_unmap(vcpu, &vmx->nested.pi_desc_map); vmx->nested.pi_desc = NULL; } @@ -624,7 +624,7 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu, int msr; unsigned long *msr_bitmap_l1; unsigned long *msr_bitmap_l0 = vmx->nested.vmcs02.msr_bitmap; - struct kvm_host_map msr_bitmap_map; + struct kvm_host_map map; /* Nothing to do if the MSR bitmap is not in use. */ if (!cpu_has_vmx_msr_bitmap() || @@ -647,10 +647,10 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu, return true; } - if (kvm_vcpu_map(vcpu, gpa_to_gfn(vmcs12->msr_bitmap), &msr_bitmap_map)) + if (kvm_vcpu_map_readonly(vcpu, gpa_to_gfn(vmcs12->msr_bitmap), &map)) return false; - msr_bitmap_l1 = (unsigned long *)msr_bitmap_map.hva; + msr_bitmap_l1 = (unsigned long *)map.hva; /* * To keep the control flow simple, pay eight 8-byte writes (sixteen @@ -714,7 +714,7 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu, nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0, MSR_IA32_FLUSH_CMD, MSR_TYPE_W); - kvm_vcpu_unmap(vcpu, &msr_bitmap_map, false); + kvm_vcpu_unmap(vcpu, &map); vmx->nested.force_msr_bitmap_recalc = false; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 8739b905d85b..9263375d0362 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -285,6 +285,7 @@ struct kvm_host_map { void *hva; kvm_pfn_t pfn; kvm_pfn_t gfn; + bool writable; }; /* @@ -1312,8 +1313,23 @@ void mark_page_dirty(struct kvm *kvm, gfn_t gfn); struct kvm_memslots *kvm_vcpu_memslots(struct kvm_vcpu *vcpu); struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn); kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn); -int kvm_vcpu_map(struct kvm_vcpu *vcpu, gpa_t gpa, struct kvm_host_map *map); -void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty); + +int __kvm_vcpu_map(struct kvm_vcpu *vcpu, gpa_t gpa, struct kvm_host_map *map, + bool writable); +void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map); + +static inline int kvm_vcpu_map(struct kvm_vcpu *vcpu, gpa_t gpa, + struct kvm_host_map *map) +{ + return __kvm_vcpu_map(vcpu, gpa, map, true); +} + +static inline int kvm_vcpu_map_readonly(struct kvm_vcpu *vcpu, gpa_t gpa, + struct kvm_host_map *map) +{ + return __kvm_vcpu_map(vcpu, gpa, map, false); +} + unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn); unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable); int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data, int offset, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 40a59526d466..080740f65061 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3116,7 +3116,8 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_page); -int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map) +int __kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map, + bool writable) { struct kvm_follow_pfn kfp = { .slot = gfn_to_memslot(vcpu->kvm, gfn), @@ -3130,6 +3131,7 @@ int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map) map->page = NULL; map->hva = NULL; map->gfn = gfn; + map->writable = writable; map->pfn = kvm_follow_pfn(&kfp); if (is_error_noslot_pfn(map->pfn)) @@ -3146,9 +3148,9 @@ int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map) return map->hva ? 0 : -EFAULT; } -EXPORT_SYMBOL_GPL(kvm_vcpu_map); +EXPORT_SYMBOL_GPL(__kvm_vcpu_map); -void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty) +void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map) { if (!map->hva) return; @@ -3160,11 +3162,11 @@ void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty) memunmap(map->hva); #endif - if (dirty) + if (map->writable) kvm_vcpu_mark_page_dirty(vcpu, map->gfn); if (map->pinned_page) { - if (dirty) + if (map->writable) kvm_set_page_dirty(map->pinned_page); kvm_set_page_accessed(map->pinned_page); unpin_user_page(map->pinned_page);