From nobody Thu Dec 18 07:10:27 2025 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 71E73C61D85 for ; Tue, 21 Nov 2023 18:03:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234270AbjKUSDY (ORCPT ); Tue, 21 Nov 2023 13:03:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229472AbjKUSDV (ORCPT ); Tue, 21 Nov 2023 13:03:21 -0500 Received: from mail.xenproject.org (mail.xenproject.org [104.130.215.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7CD8E8; Tue, 21 Nov 2023 10:03:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-Id:Date:Subject:To:From; bh=DVmkuHvAJAn35Oz9caMUxenePj8iuuNulYJyd17+sk4=; b=FmZVDA65pSC87L/E1ks/JBoj5U 3UAjffFNSdc8l7SXhtkGZIHbB1KSOCrF9L/KBf3N17NTELO5n4emg2Z0ykJ7q53VbkatuG6zjyj1P jJRKZS9DOg79xs87u7GOkt5xyjinz8503nH3gLCIW45LOI/f6e5+09y9BR0hA0smVitM=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1r5V5R-00083w-M7; Tue, 21 Nov 2023 18:03:01 +0000 Received: from 54-240-197-231.amazon.com ([54.240.197.231] helo=REM-PW02S00X.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r5V5R-0004Z3-Cv; Tue, 21 Nov 2023 18:03:01 +0000 From: Paul Durrant To: David Woodhouse , Paul Durrant , Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v8 01/15] KVM: pfncache: Add a map helper function Date: Tue, 21 Nov 2023 18:02:09 +0000 Message-Id: <20231121180223.12484-2-paul@xen.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231121180223.12484-1-paul@xen.org> References: <20231121180223.12484-1-paul@xen.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Paul Durrant There is a pfncache unmap helper but mapping is open-coded. Arguably this is fine because mapping is done in only one place, hva_to_pfn_retry(), but adding the helper does make that function more readable. No functional change intended. Signed-off-by: Paul Durrant Reviewed-by: David Woodhouse --- Cc: Sean Christopherson Cc: David Woodhouse Cc: Paolo Bonzini v8: - Re-work commit comment. - Fix CONFIG_HAS_IOMEM=3Dn build. --- virt/kvm/pfncache.c | 47 ++++++++++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 18 deletions(-) diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c index 2d6aba677830..10842f1eeeae 100644 --- a/virt/kvm/pfncache.c +++ b/virt/kvm/pfncache.c @@ -96,17 +96,32 @@ bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, unsign= ed long len) } EXPORT_SYMBOL_GPL(kvm_gpc_check); =20 -static void gpc_unmap_khva(kvm_pfn_t pfn, void *khva) +static void *gpc_map(kvm_pfn_t pfn) { - /* Unmap the old pfn/page if it was mapped before. */ - if (!is_error_noslot_pfn(pfn) && khva) { - if (pfn_valid(pfn)) - kunmap(pfn_to_page(pfn)); + if (pfn_valid(pfn)) + return kmap(pfn_to_page(pfn)); + #ifdef CONFIG_HAS_IOMEM - else - memunmap(khva); + return memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB); +#else + return NULL; #endif +} + +static void gpc_unmap(kvm_pfn_t pfn, void *khva) +{ + /* Unmap the old pfn/page if it was mapped before. */ + if (is_error_noslot_pfn(pfn) || !khva) + return; + + if (pfn_valid(pfn)) { + kunmap(pfn_to_page(pfn)); + return; } + +#ifdef CONFIG_HAS_IOMEM + memunmap(khva); +#endif } =20 static inline bool mmu_notifier_retry_cache(struct kvm *kvm, unsigned long= mmu_seq) @@ -175,7 +190,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cac= he *gpc) * the existing mapping and didn't create a new one. */ if (new_khva !=3D old_khva) - gpc_unmap_khva(new_pfn, new_khva); + gpc_unmap(new_pfn, new_khva); =20 kvm_release_pfn_clean(new_pfn); =20 @@ -193,15 +208,11 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_c= ache *gpc) * too must be done outside of gpc->lock! */ if (gpc->usage & KVM_HOST_USES_PFN) { - if (new_pfn =3D=3D gpc->pfn) { + if (new_pfn =3D=3D gpc->pfn) new_khva =3D old_khva; - } else if (pfn_valid(new_pfn)) { - new_khva =3D kmap(pfn_to_page(new_pfn)); -#ifdef CONFIG_HAS_IOMEM - } else { - new_khva =3D memremap(pfn_to_hpa(new_pfn), PAGE_SIZE, MEMREMAP_WB); -#endif - } + else + new_khva =3D gpc_map(new_pfn); + if (!new_khva) { kvm_release_pfn_clean(new_pfn); goto out_error; @@ -326,7 +337,7 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *g= pc, gpa_t gpa, mutex_unlock(&gpc->refresh_lock); =20 if (unmap_old) - gpc_unmap_khva(old_pfn, old_khva); + gpc_unmap(old_pfn, old_khva); =20 return ret; } @@ -412,7 +423,7 @@ void kvm_gpc_deactivate(struct gfn_to_pfn_cache *gpc) list_del(&gpc->list); spin_unlock(&kvm->gpc_lock); =20 - gpc_unmap_khva(old_pfn, old_khva); + gpc_unmap(old_pfn, old_khva); } } EXPORT_SYMBOL_GPL(kvm_gpc_deactivate); --=20 2.39.2