From patchwork Mon Oct 2 09:57:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 13405780 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 2D2D3E784AF for ; Mon, 2 Oct 2023 09:57:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236288AbjJBJ56 (ORCPT ); Mon, 2 Oct 2023 05:57:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236298AbjJBJ55 (ORCPT ); Mon, 2 Oct 2023 05:57:57 -0400 Received: from mail.xenproject.org (mail.xenproject.org [104.130.215.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06A74B0; Mon, 2 Oct 2023 02:57:53 -0700 (PDT) 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:Cc:To:From; bh=cQ02ZWi3OXJZ36oKzuEnX4ff/ZDsG5TQqSf2+fKM4a0=; b=HktkN30axQojx0wotuTnOunyDm Y1xDKecGGk/+oX9k0SJo22r+q4XAISbQl2Bp/rjKt385sqQtXE5apQbl7D57aD+dxIjO9PRnSjNCL v+IIvQlm1V7YsZzU0g4OAGXnbC1l9/ZYT/quiL8Af1UUuEeuGuV2Rj+VmYFNqz7q7v5A=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qnFgT-0000v6-O5; Mon, 02 Oct 2023 09:57:49 +0000 Received: from ec2-63-33-11-17.eu-west-1.compute.amazonaws.com ([63.33.11.17] 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 1qnFgT-0000Ft-GD; Mon, 02 Oct 2023 09:57:49 +0000 From: Paul Durrant To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Paul Durrant , David Woodhouse , Sean Christopherson , David Woodhouse , Paolo Bonzini Subject: [PATCH v7 01/11] KVM: pfncache: add a map helper function Date: Mon, 2 Oct 2023 09:57:30 +0000 Message-Id: <20231002095740.1472907-2-paul@xen.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231002095740.1472907-1-paul@xen.org> References: <20231002095740.1472907-1-paul@xen.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Paul Durrant We have an 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 --- virt/kvm/pfncache.c | 43 +++++++++++++++++++++++++------------------ 1 file changed, 25 insertions(+), 18 deletions(-) diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c index 2d6aba677830..0f36acdf577f 100644 --- a/virt/kvm/pfncache.c +++ b/virt/kvm/pfncache.c @@ -96,17 +96,28 @@ bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, unsigned long len) } EXPORT_SYMBOL_GPL(kvm_gpc_check); -static void gpc_unmap_khva(kvm_pfn_t pfn, void *khva) +static void *gpc_map(kvm_pfn_t pfn) +{ + if (pfn_valid(pfn)) + return kmap(pfn_to_page(pfn)); +#ifdef CONFIG_HAS_IOMEM + else + return memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB); +#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) { - if (pfn_valid(pfn)) - kunmap(pfn_to_page(pfn)); + if (is_error_noslot_pfn(pfn) || !khva) + return; + + if (pfn_valid(pfn)) + kunmap(pfn_to_page(pfn)); #ifdef CONFIG_HAS_IOMEM - else - memunmap(khva); + else + memunmap(khva); #endif - } } static inline bool mmu_notifier_retry_cache(struct kvm *kvm, unsigned long mmu_seq) @@ -175,7 +186,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) * the existing mapping and didn't create a new one. */ if (new_khva != old_khva) - gpc_unmap_khva(new_pfn, new_khva); + gpc_unmap(new_pfn, new_khva); kvm_release_pfn_clean(new_pfn); @@ -193,15 +204,11 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) * too must be done outside of gpc->lock! */ if (gpc->usage & KVM_HOST_USES_PFN) { - if (new_pfn == gpc->pfn) { + if (new_pfn == gpc->pfn) new_khva = old_khva; - } else if (pfn_valid(new_pfn)) { - new_khva = kmap(pfn_to_page(new_pfn)); -#ifdef CONFIG_HAS_IOMEM - } else { - new_khva = memremap(pfn_to_hpa(new_pfn), PAGE_SIZE, MEMREMAP_WB); -#endif - } + else + new_khva = gpc_map(new_pfn); + if (!new_khva) { kvm_release_pfn_clean(new_pfn); goto out_error; @@ -326,7 +333,7 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, mutex_unlock(&gpc->refresh_lock); if (unmap_old) - gpc_unmap_khva(old_pfn, old_khva); + gpc_unmap(old_pfn, old_khva); return ret; } @@ -412,7 +419,7 @@ void kvm_gpc_deactivate(struct gfn_to_pfn_cache *gpc) list_del(&gpc->list); spin_unlock(&kvm->gpc_lock); - gpc_unmap_khva(old_pfn, old_khva); + gpc_unmap(old_pfn, old_khva); } } EXPORT_SYMBOL_GPL(kvm_gpc_deactivate);