From patchwork Mon May 14 14:43:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 10398589 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 1F979600D0 for ; Mon, 14 May 2018 14:47:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0E0AB2787C for ; Mon, 14 May 2018 14:47:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 018D227F4B; Mon, 14 May 2018 14:47:36 +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 3F1CB2787C for ; Mon, 14 May 2018 14:47:36 +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=HHhsLq1mOTJtMPEN56LA82Pm7Ijtp8rxMAz3DOvi0pg=; b=qww9uSFoLsB6GfxCt4IoWQNnof elMW5Isem2fhz2PmkCC/hiZAXgJrl5m0Vyxj9xcoHt9ZAYAsmYuQrFAFr21k7nqRF9waxeaaTppvM Vs9tQvwLLrsFaS3x07rPmhojl2QVrBLpBHxc7O1JB3LRVeZkLVssGZ1slBp0BLceucuoy+KwQ7hHg 0+3xGMe81U+5DXXcz34GP9jxCQWil4nY03MoyG3g/NMwg0rj45uQUo27GuZzO0LJeM0NEtESVve1n GANCol662im6/ce/JHLvruNa7eHhrjhJT/cC0hLf6dOFMtSnvAMgXd0hjNzUbPS9RiqVttA+8zjPU aAxmhZAw==; 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 1fIEl3-0005Ff-3W; Mon, 14 May 2018 14:47:25 +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 1fIEhb-0001zl-Rv for linux-arm-kernel@lists.infradead.org; Mon, 14 May 2018 14:43:56 +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 0E933169F; Mon, 14 May 2018 07:43:44 -0700 (PDT) Received: from localhost (e105922-lin.cambridge.arm.com [10.1.206.33]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 849DB3F25D; Mon, 14 May 2018 07:43:43 -0700 (PDT) From: Punit Agrawal To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v3 3/4] KVM: arm64: Support dirty page tracking for PUD hugepages Date: Mon, 14 May 2018 15:43:03 +0100 Message-Id: <20180514144304.10484-4-punit.agrawal@arm.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180514144304.10484-1-punit.agrawal@arm.com> References: <20180514144304.10484-1-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-20180514_074351_951907_57A2CD2B X-CRM114-Status: GOOD ( 15.76 ) 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 Reviewed-by: Christoffer Dall Cc: Marc Zyngier Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon --- 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 0beefcc5e090..671d3c0825f2 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); }