From patchwork Thu Sep 14 08:49:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 13384879 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 70A43EDE99C for ; Thu, 14 Sep 2023 09:07:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236908AbjINJHX (ORCPT ); Thu, 14 Sep 2023 05:07:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236840AbjINJHP (ORCPT ); Thu, 14 Sep 2023 05:07:15 -0400 X-Greylist: delayed 1013 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 14 Sep 2023 02:07:10 PDT Received: from mail.xenproject.org (mail.xenproject.org [104.130.215.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05C7A1FEC; Thu, 14 Sep 2023 02:07:09 -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=Vg4nybFPifYv4mCdEydLFQh8wTvl7sWSN8mffLcAAaU=; b=Q/8QIj5be1SceDQi1cPfTcBAyx 3H4yVzw6rXOO6n4wDzHHnH+RRR7RzZYd7hXqLqssTdhW6JwDEv9T0pqHP6Y4znpK7OpohiOW/41Db L+30vbJxYAJkyusxE4GvnXaNEQhbbYZNEcxWd2WejYZermQUKYIlbVLVzol+EhF0Rx9I=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qgi3F-0001iU-DL; Thu, 14 Sep 2023 08:50:17 +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 1qgi3F-0002T9-58; Thu, 14 Sep 2023 08:50:17 +0000 From: Paul Durrant To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Paul Durrant , Paolo Bonzini , David Woodhouse Subject: [PATCH 1/8] KVM: pfncache: add a map helper function Date: Thu, 14 Sep 2023 08:49:39 +0000 Message-Id: <20230914084946.200043-2-paul@xen.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230914084946.200043-1-paul@xen.org> References: <20230914084946.200043-1-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. Signed-off-by: Paul Durrant Reviewed-by: David Woodhouse --- Cc: Paolo Bonzini Cc: David Woodhouse --- 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);