From patchwork Mon Jul 9 14:41:20 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 10514813 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 0D26C6032A for ; Mon, 9 Jul 2018 14:55:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F13B228CB7 for ; Mon, 9 Jul 2018 14:55:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E540828CBC; Mon, 9 Jul 2018 14:55:45 +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 EB2A628CB7 for ; Mon, 9 Jul 2018 14:55:44 +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=hy9HHm4fV2KpD7zHaXVwRGwkrFGdMHJc8W6E5ngpu/o=; b=VeksQv7B6dYrP54y6bR4irL1ab G9GsSbGb99bIcyFQPjpgNlCkGjuHlejwSbUoa0Y4aKuXXJasfmlKXi6Fl2OQB1OHZTR+LdkDn8wKB EDidx5Ww9t9UN1sQgEowzgTCNRx9P6MQyxwgxW7ZY1z04iUZHJ35jKFVZaYa0bgANsmh+T2NcxFaX +hJZYk4vL3NYzPVITrUG7lnKuN9f6bRUdo+IjT8XwOxAWvO57B2umqFFtr7p00B3pmG9ZTy0nQKS4 tm0FT7+KqMDyZkpG4XWIdmKqwMJhDOwKPHb7MaOMR5Hf8yCqW9u3hNYcWZqxRQMcB+aILJSLzFeho ufXUt8Cg==; 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 1fcXZn-0002t1-6R; Mon, 09 Jul 2018 14:55:43 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fcXMR-0001hY-Uk for linux-arm-kernel@lists.infradead.org; Mon, 09 Jul 2018 14:42:01 +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 D325A1684; Mon, 9 Jul 2018 07:41:45 -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 54A203F589; Mon, 9 Jul 2018 07:41:45 -0700 (PDT) From: Punit Agrawal To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v5 3/7] KVM: arm64: Support dirty page tracking for PUD hugepages Date: Mon, 9 Jul 2018 15:41:20 +0100 Message-Id: <20180709144124.29164-3-punit.agrawal@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180709144124.29164-1-punit.agrawal@arm.com> References: <20180709143835.28971-1-punit.agrawal@arm.com> <20180709144124.29164-1-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-20180709_074156_882422_5D290B69 X-CRM114-Status: GOOD ( 16.10 ) 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@arm.com, 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 Reviewed-by: Suzuki K Poulose --- arch/arm/include/asm/kvm_mmu.h | 16 ++++++++++++++++ arch/arm64/include/asm/kvm_mmu.h | 10 ++++++++++ virt/kvm/arm/mmu.c | 11 +++++++---- 3 files changed, 33 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index d095c2d0b284..c23722f75d5c 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 689def9bb9d5..84051930ddfe 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -239,6 +239,16 @@ 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 e131b7f9b7d7..ed8f8271c389 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1288,9 +1288,12 @@ 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); } @@ -1333,7 +1336,7 @@ 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,