From patchwork Fri Apr 20 14:54:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 10352961 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D046E6023A for ; Fri, 20 Apr 2018 15:10:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BD6572870C for ; Fri, 20 Apr 2018 15:10:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ACDEA2879D; Fri, 20 Apr 2018 15:10:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 33E0B2870C for ; Fri, 20 Apr 2018 15:10:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=iLx0Xwg1AAzvjnTTAiC1MhcMef6fb0gVo0CZ0+BsjMs=; b=JsGZ6kSfCBBmbVKtDZ+9z7OJtK 3EgQHpesvhMtjszpz27VtfQofVERoatcpImpXdTexeK7gAPwMRwJ9g1Oj3lj9k0ApH7qrv2WHGeZp DyzGjbmjV5UWuHrXOwd6QzF7IMOujSIhYWT67MzQxwgsxsa59GcgICu2JR+3iQpYuufQi66pBg48l 6e+4N8v6aOn3PdukuFd64GcVk5zQgv3q9yzqKgCqeLo+eZDyWqcz5eYBOT+2wCKo+EOzsGcLFnWiM keaOp7AGiwbQNRv2g6hn7FkABd+ZAmpYpUsmKaKc7CK2gRmuhkIstaP8MaY3qypv16ickA85/U6KM 1ngbH0cA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1f9Xfo-0005tB-Uj; Fri, 20 Apr 2018 15:10:04 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1f9XRy-0007Nu-W8 for linux-arm-kernel@lists.infradead.org; Fri, 20 Apr 2018 14:55:50 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A8CB580D; Fri, 20 Apr 2018 07:55:36 -0700 (PDT) Received: from localhost (e105922-lin.cambridge.arm.com [10.1.207.29]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2AC1A3F59D; Fri, 20 Apr 2018 07:55:36 -0700 (PDT) From: Punit Agrawal To: kvmarm@lists.cs.columbia.edu Subject: [PATCH 3/4] KVM: arm64: Support dirty page tracking for PUD hugepages Date: Fri, 20 Apr 2018 15:54:08 +0100 Message-Id: <20180420145409.24485-4-punit.agrawal@arm.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180420145409.24485-1-punit.agrawal@arm.com> References: <20180420145409.24485-1-punit.agrawal@arm.com> X-ARM-No-Footer: FoSSMail X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180420_075547_142162_39AD15F5 X-CRM114-Status: GOOD ( 15.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: suzuki.poulose@arm.com, marc.zyngier@arm.com, Catalin Marinas , Punit Agrawal , Will Deacon , christoffer.dall@arm.com, linux-kernel@vger.kernel.org, Russell King , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In preparation for creating PUD hugepages at stage 2, add support for write protecting PUD hugepages when they are encountered. Write protecting guest tables is used to track dirty pages when migrating VMs. Also, provide trivial implementations of required kvm_s2pud_* helpers to allow sharing of code with arm32. Signed-off-by: Punit Agrawal Cc: Christoffer Dall Cc: Marc Zyngier Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Reviewed-by: Christoffer Dall --- arch/arm/include/asm/kvm_mmu.h | 16 ++++++++++++++++ arch/arm64/include/asm/kvm_mmu.h | 10 ++++++++++ virt/kvm/arm/mmu.c | 9 ++++++--- 3 files changed, 32 insertions(+), 3 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 5907a81ad5c1..224c22c0a69c 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -80,6 +80,22 @@ void kvm_clear_hyp_idmap(void); #define kvm_pmd_mkhuge(pmd) pmd_mkhuge(pmd) +/* + * The following kvm_*pud*() functionas are provided strictly to allow + * sharing code with arm64. They should never be called in practice. + */ +static inline void kvm_set_s2pud_readonly(pud_t *pud) +{ + BUG(); +} + +static inline bool kvm_s2pud_readonly(pud_t *pud) +{ + BUG(); + return false; +} + + static inline void kvm_set_pmd(pmd_t *pmd, pmd_t new_pmd) { *pmd = new_pmd; diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index d962508ce4b3..f440cf216a23 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -240,6 +240,16 @@ static inline bool kvm_s2pmd_exec(pmd_t *pmdp) return !(READ_ONCE(pmd_val(*pmdp)) & PMD_S2_XN); } +static inline void kvm_set_s2pud_readonly(pud_t *pudp) +{ + kvm_set_s2pte_readonly((pte_t *)pudp); +} + +static inline bool kvm_s2pud_readonly(pud_t *pudp) +{ + return kvm_s2pte_readonly((pte_t *)pudp); +} + static inline bool kvm_page_empty(void *ptr) { struct page *ptr_page = virt_to_page(ptr); diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index f72ae7a6dea0..5f53909da90e 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1286,9 +1286,12 @@ static void stage2_wp_puds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end) do { next = stage2_pud_addr_end(addr, end); if (!stage2_pud_none(*pud)) { - /* TODO:PUD not supported, revisit later if supported */ - BUG_ON(stage2_pud_huge(*pud)); - stage2_wp_pmds(pud, addr, next); + if (stage2_pud_huge(*pud)) { + if (!kvm_s2pud_readonly(pud)) + kvm_set_s2pud_readonly(pud); + } else { + stage2_wp_pmds(pud, addr, next); + } } } while (pud++, addr = next, addr != end); }