From patchwork Wed Dec 19 18:03:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 10737903 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BD18513BF for ; Wed, 19 Dec 2018 18:06:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AAAE02B6D4 for ; Wed, 19 Dec 2018 18:06:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9DBCF2B7A7; Wed, 19 Dec 2018 18:06:33 +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=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED 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 2E63A2B6D4 for ; Wed, 19 Dec 2018 18:06:33 +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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version: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=JdnXXMzs+CzhSJeEQf2pnJS0EH/dikr+8/ZGviXntuY=; b=lLhYEjGGgyPnuT 8Lcjlox4GQj6G9IBWDj4SHBWs1U4DweEIBWc7EuHPl0iHAx4cF6s40BrgXr9p4d9E1CNk8FvuW4fm eXGa1ywxMHXgkILD8/huqfnlr4Tbhc85RzaI8vHUEojmxnhfaK23Mgf57676k4df8w/4VkoifJDrI LVjh/yTM2e7j1f4PrIBt/QtIhQTIjio3giozpqNiGw8OQ0DqbS5K4BSm8mUpFkuysPrGibrRRP+gE ZhRdgRddQK4BOF9FQvD3fdupQqB2ogNlTCAHQ4sedZ6LCCg7Tur0sCcSxKRIdt9BHR8SRvQahlgZC eOuHygozpWrM4PhhP2Pg==; 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 1gZgEl-0000TG-SA; Wed, 19 Dec 2018 18:06:27 +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 1gZgCx-00061r-Ny for linux-arm-kernel@lists.infradead.org; Wed, 19 Dec 2018 18:04:37 +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 9163B165C; Wed, 19 Dec 2018 10:04:34 -0800 (PST) Received: from filthy-habits.cambridge.arm.com (filthy-habits.cambridge.arm.com [10.1.196.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 121D83F675; Wed, 19 Dec 2018 10:04:31 -0800 (PST) From: Marc Zyngier To: Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= Subject: [PATCH 09/28] KVM: arm64: Support dirty page tracking for PUD hugepages Date: Wed, 19 Dec 2018 18:03:30 +0000 Message-Id: <20181219180349.242681-10-marc.zyngier@arm.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181219180349.242681-1-marc.zyngier@arm.com> References: <20181219180349.242681-1-marc.zyngier@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181219_100435_920427_1930AC83 X-CRM114-Status: GOOD ( 15.19 ) 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: Mark Rutland , Punit Agrawal , kvm@vger.kernel.org, Julien Thierry , "Gustavo A . R . Silva" , Will Deacon , Christoffer Dall , linux-arm-kernel@lists.infradead.org, punitagrawal@gmail.com, =?utf-8?q?Ale?= =?utf-8?q?x_Benn=C3=A9e?= , kvmarm@lists.cs.columbia.edu, Suzuki Poulose , Lukas Braun 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 From: Punit Agrawal 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: Russell King Cc: Catalin Marinas Cc: Will Deacon [ Replaced BUG() => WARN_ON() in arm32 pud helpers ] Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_mmu.h | 15 +++++++++++++++ arch/arm64/include/asm/kvm_mmu.h | 10 ++++++++++ virt/kvm/arm/mmu.c | 11 +++++++---- 3 files changed, 32 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index e6eff8bf5d7f..9fe6c30eb2fc 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -87,6 +87,21 @@ void kvm_clear_hyp_idmap(void); #define kvm_pmd_mkhuge(pmd) pmd_mkhuge(pmd) +/* + * The following kvm_*pud*() functions 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) +{ + WARN_ON(1); +} + +static inline bool kvm_s2pud_readonly(pud_t *pud) +{ + WARN_ON(1); + return false; +} + static inline pte_t kvm_s2pte_mkwrite(pte_t pte) { pte_val(pte) |= L_PTE_S2_RDWR; diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 13d482710292..8da6d1b2a196 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -251,6 +251,16 @@ 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); +} + #define hyp_pte_table_empty(ptep) kvm_page_empty(ptep) #ifdef __PAGETABLE_PMD_FOLDED diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index fb5325f7a1ac..1c669c3c1208 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1347,9 +1347,12 @@ static void stage2_wp_puds(struct kvm *kvm, pgd_t *pgd, do { next = stage2_pud_addr_end(kvm, addr, end); if (!stage2_pud_none(kvm, *pud)) { - /* TODO:PUD not supported, revisit later if supported */ - BUG_ON(stage2_pud_huge(kvm, *pud)); - stage2_wp_pmds(kvm, pud, addr, next); + if (stage2_pud_huge(kvm, *pud)) { + if (!kvm_s2pud_readonly(pud)) + kvm_set_s2pud_readonly(pud); + } else { + stage2_wp_pmds(kvm, pud, addr, next); + } } } while (pud++, addr = next, addr != end); } @@ -1392,7 +1395,7 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) * * Called to start logging dirty pages after memory region * KVM_MEM_LOG_DIRTY_PAGES operation is called. After this function returns - * all present PMD and PTEs are write protected in the memory region. + * all present PUD, PMD and PTEs are write protected in the memory region. * Afterwards read of dirty page log can be called. * * Acquires kvm_mmu_lock. Called with kvm->slots_lock mutex acquired,