Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754792AbaGHNAn (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" 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 Content-Type: text/plain X-Originating-IP: [10.167.226.99] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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)); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/