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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 DC35CC4338F for ; Mon, 26 Jul 2021 15:35:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA45560E08 for ; Mon, 26 Jul 2021 15:35:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235010AbhGZOz3 (ORCPT ); Mon, 26 Jul 2021 10:55:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:37132 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234710AbhGZOz2 (ORCPT ); Mon, 26 Jul 2021 10:55:28 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7E4ED60462; Mon, 26 Jul 2021 15:35:57 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1m82e3-001511-Qz; Mon, 26 Jul 2021 16:35:55 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-mm@kvack.org Cc: Sean Christopherson , Matthew Wilcox , Paolo Bonzini , Will Deacon , Quentin Perret , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com Subject: [PATCH v2 1/6] KVM: arm64: Introduce helper to retrieve a PTE and its level Date: Mon, 26 Jul 2021 16:35:47 +0100 Message-Id: <20210726153552.1535838-2-maz@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210726153552.1535838-1-maz@kernel.org> References: <20210726153552.1535838-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-mm@kvack.org, seanjc@google.com, willy@infradead.org, pbonzini@redhat.com, will@kernel.org, qperret@google.com, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org It is becoming a common need to fetch the PTE for a given address together with its level. Add such a helper. Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_pgtable.h | 19 ++++++++++++++ arch/arm64/kvm/hyp/pgtable.c | 39 ++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+) diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index f004c0115d89..082b9d65f40b 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -432,6 +432,25 @@ int kvm_pgtable_stage2_flush(struct kvm_pgtable *pgt, u64 addr, u64 size); int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, struct kvm_pgtable_walker *walker); +/** + * kvm_pgtable_get_leaf() - Walk a page-table and retrieve the leaf entry + * with its level. + * @pgt: Page-table structure initialised by kvm_pgtable_*_init(). + * @addr: Input address for the start of the walk. + * @ptep: Pointer to storage for the retrieved PTE. + * @level: Pointer to storage for the level of the retrieved PTE. + * + * The offset of @addr within a page is ignored. + * + * The walker will walk the page-table entries corresponding to the input + * address specified, retrieving the leaf corresponding to this address. + * Invalid entries are treated as leaf entries. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_get_leaf(struct kvm_pgtable *pgt, u64 addr, + kvm_pte_t *ptep, u32 *level); + /** * kvm_pgtable_stage2_find_range() - Find a range of Intermediate Physical * Addresses with compatible permission diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 05321f4165e3..78f36bd5df6c 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -326,6 +326,45 @@ int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, return _kvm_pgtable_walk(&walk_data); } +struct leaf_walk_data { + kvm_pte_t pte; + u32 level; +}; + +static int leaf_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, void * const arg) +{ + struct leaf_walk_data *data = arg; + + data->pte = *ptep; + data->level = level; + + return 0; +} + +int kvm_pgtable_get_leaf(struct kvm_pgtable *pgt, u64 addr, + kvm_pte_t *ptep, u32 *level) +{ + struct leaf_walk_data data; + struct kvm_pgtable_walker walker = { + .cb = leaf_walker, + .flags = KVM_PGTABLE_WALK_LEAF, + .arg = &data, + }; + int ret; + + ret = kvm_pgtable_walk(pgt, ALIGN_DOWN(addr, PAGE_SIZE), + PAGE_SIZE, &walker); + if (!ret) { + if (ptep) + *ptep = data.pte; + if (level) + *level = data.level; + } + + return ret; +} + struct hyp_map_data { u64 phys; kvm_pte_t attr; -- 2.30.2