From patchwork Tue Jul 8 13:01:28 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: tangchen X-Patchwork-Id: 4504741 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id D4F7E9F392 for ; Tue, 8 Jul 2014 13:01:19 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id ED19B2037A for ; Tue, 8 Jul 2014 13:01:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E0A1720364 for ; Tue, 8 Jul 2014 13:01:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754771AbaGHNAn (ORCPT ); Tue, 8 Jul 2014 09:00:43 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:29969 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754440AbaGHNAk (ORCPT ); Tue, 8 Jul 2014 09:00:40 -0400 X-IronPort-AV: E=Sophos;i="5.00,856,1396972800"; d="scan'208";a="32994959" Received: from localhost (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 08 Jul 2014 20:57:54 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id s68D0aYN030903; Tue, 8 Jul 2014 21:00:36 +0800 Received: from G08FNSTD090432.fnst.cn.fujitsu.com (10.167.226.99) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Tue, 8 Jul 2014 21:00:42 +0800 From: Tang Chen To: , , CC: , , , , , Subject: [PATCH v2 1/5] kvm: Add gfn_to_page_no_pin() to translate gfn to page without pinning. Date: Tue, 8 Jul 2014 21:01:28 +0800 Message-ID: <1404824492-30095-2-git-send-email-tangchen@cn.fujitsu.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1404824492-30095-1-git-send-email-tangchen@cn.fujitsu.com> References: <1404824492-30095-1-git-send-email-tangchen@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.99] Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP gfn_to_page() will finally call hva_to_pfn() to get the pfn, and pin the page in memory by calling GUP functions. This function unpins the page. Will be used by the followed patches. Signed-off-by: Tang Chen --- include/linux/kvm_host.h | 1 + virt/kvm/kvm_main.c | 17 ++++++++++++++++- 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ec4e3bd..7c58d9d 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -541,6 +541,7 @@ int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages, int nr_pages); struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); +struct page *gfn_to_page_no_pin(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable); unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 4b6c01b..6091849 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1371,9 +1371,24 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) return kvm_pfn_to_page(pfn); } - EXPORT_SYMBOL_GPL(gfn_to_page); +struct page *gfn_to_page_no_pin(struct kvm *kvm, gfn_t gfn) +{ + struct page *page = gfn_to_page(kvm, gfn); + + /* + * gfn_to_page() will finally call hva_to_pfn() to get the pfn, and pin + * the page in memory by calling GUP functions. This function unpins + * the page. + */ + if (!is_error_page(page)) + put_page(page); + + return page; +} +EXPORT_SYMBOL_GPL(gfn_to_page_no_pin); + void kvm_release_page_clean(struct page *page) { WARN_ON(is_error_page(page));