From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2191C43461 for ; Mon, 7 Sep 2020 15:27:20 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6C2262078E for ; Mon, 7 Sep 2020 15:27:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="3KRJY+Rs"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="tgbSHwU2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C2262078E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.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=EMYtiwdt55EVNUNlTKlRufiTGkwo64ZCveeikl5aWDA=; b=3KRJY+RsjVBp6+VvSCoRel/MS A4SasBkYCANGWpmyJW0uOk8Q2jmXaSNA4VrnMNuQfvgRz929zHFf4v8K5AV5zBwZb/58I7ZpcZDzJ ERqDLk3ZSk89FGBONIIKX1/DBPWJM7ySif6kH6OKnXOUqGrPoiel+hwzDz2TSKE8P3IrGya/YnSpC 2bvnwguGN91ylhCn9AFoZNB9xyOm4qrNet+T5o2UZmg0VxCO8cTU+TOZQqGGb9U/B0b1opMdP2p6D zNxmZIdsydKD0PgjgjOYnokUN6NE1DYafPya5t7Reo8Bp2zTvA9Dl/PBSE0pbbRFZhTFPDDHHvadn 5PfFOSRWw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kFJ1O-0006MQ-1l; Mon, 07 Sep 2020 15:25:30 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kFJ0D-0005rW-Ku for linux-arm-kernel@lists.infradead.org; Mon, 07 Sep 2020 15:24:19 +0000 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 147B421775; Mon, 7 Sep 2020 15:24:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599492256; bh=aS47EmzFe+L7DXEvRrSpT4WpJ1/lAL0Hx2OhZnJcdtQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tgbSHwU2ZIDtzU8Z3/8u/NBS7ysmlYtojdNbKp8im22j0YTdHqcc4Ilq7VPfszXBn NI2MaRlQ/64wHbfQ4s503CO7hSoVdbrLSdk3bShFQLDo/Z2+9COFeDdwnaOpDgKqyZ mFTrJ7vjaBRVM3SmEaNcA/oedmJRjKyzbmwdoSmU= From: Will Deacon To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v4 10/21] KVM: arm64: Add support for stage-2 page-aging in generic page-table Date: Mon, 7 Sep 2020 16:23:33 +0100 Message-Id: <20200907152344.12978-11-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200907152344.12978-1-will@kernel.org> References: <20200907152344.12978-1-will@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200907_112417_861429_662D41A3 X-CRM114-Status: GOOD ( 21.35 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kernel-team@android.com, Gavin Shan , Suzuki Poulose , Marc Zyngier , Quentin Perret , Alexandru Elisei , James Morse , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add stage-2 mkyoung(), mkold() and is_young() operations to the generic page-table code. Cc: Marc Zyngier Cc: Quentin Perret Reviewed-by: Gavin Shan Signed-off-by: Will Deacon --- arch/arm64/include/asm/kvm_pgtable.h | 38 ++++++++++++ arch/arm64/kvm/hyp/pgtable.c | 86 ++++++++++++++++++++++++++++ 2 files changed, 124 insertions(+) diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 7258966d3daa..01cad6bbc81b 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -175,6 +175,44 @@ int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, */ int kvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size); +/** + * kvm_pgtable_stage2_mkyoung() - Set the access flag in a page-table entry. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * + * If there is a valid, leaf page-table entry used to translate @addr, then + * set the access flag in that entry. + * + * Return: The old page-table entry prior to setting the flag, 0 on failure. + */ +kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); + +/** + * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * + * If there is a valid, leaf page-table entry used to translate @addr, then + * clear the access flag in that entry. + * + * Note that it is the caller's responsibility to invalidate the TLB after + * calling this function to ensure that the updated permissions are visible + * to the CPUs. + * + * Return: The old page-table entry prior to clearing the flag, 0 on failure. + */ +kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); + +/** + * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the + * access flag set. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * + * Return: True if the page-table entry has the access flag set, false otherwise. + */ +bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); + /** * kvm_pgtable_walk() - Walk a page-table. * @pgt: Page-table structure initialised by kvm_pgtable_*_init(). diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 4623380cf9de..87ff56d8bcb5 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -690,6 +690,92 @@ int kvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size) return kvm_pgtable_walk(pgt, addr, size, &walker); } +struct stage2_attr_data { + kvm_pte_t attr_set; + kvm_pte_t attr_clr; + kvm_pte_t pte; +}; + +static int stage2_attr_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, + void * const arg) +{ + kvm_pte_t pte = *ptep; + struct stage2_attr_data *data = arg; + + if (!kvm_pte_valid(pte)) + return 0; + + data->pte = pte; + pte &= ~data->attr_clr; + pte |= data->attr_set; + + /* + * We may race with the CPU trying to set the access flag here, + * but worst-case the access flag update gets lost and will be + * set on the next access instead. + */ + if (data->pte != pte) + WRITE_ONCE(*ptep, pte); + + return 0; +} + +static int stage2_update_leaf_attrs(struct kvm_pgtable *pgt, u64 addr, + u64 size, kvm_pte_t attr_set, + kvm_pte_t attr_clr, kvm_pte_t *orig_pte) +{ + int ret; + kvm_pte_t attr_mask = KVM_PTE_LEAF_ATTR_LO | KVM_PTE_LEAF_ATTR_HI; + struct stage2_attr_data data = { + .attr_set = attr_set & attr_mask, + .attr_clr = attr_clr & attr_mask, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_attr_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + ret = kvm_pgtable_walk(pgt, addr, size, &walker); + if (ret) + return ret; + + if (orig_pte) + *orig_pte = data.pte; + return 0; +} + +kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) +{ + kvm_pte_t pte = 0; + stage2_update_leaf_attrs(pgt, addr, 1, KVM_PTE_LEAF_ATTR_LO_S2_AF, 0, + &pte); + dsb(ishst); + return pte; +} + +kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +{ + kvm_pte_t pte = 0; + stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, + &pte); + /* + * "But where's the TLBI?!", you scream. + * "Over in the core code", I sigh. + * + * See the '->clear_flush_young()' callback on the KVM mmu notifier. + */ + return pte; +} + +bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +{ + kvm_pte_t pte = 0; + stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte); + return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; +} + int kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm *kvm) { size_t pgd_sz; -- 2.28.0.526.ge36021eeef-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel