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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91F7CC433EF for ; Wed, 13 Oct 2021 15:59:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79679611B0 for ; Wed, 13 Oct 2021 15:59:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236779AbhJMQBD (ORCPT ); Wed, 13 Oct 2021 12:01:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235925AbhJMQA4 (ORCPT ); Wed, 13 Oct 2021 12:00:56 -0400 Received: from mail-qk1-x74a.google.com (mail-qk1-x74a.google.com [IPv6:2607:f8b0:4864:20::74a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FA18C061764 for ; Wed, 13 Oct 2021 08:58:52 -0700 (PDT) Received: by mail-qk1-x74a.google.com with SMTP id l27-20020a05620a211b00b0045fbe374e2dso947402qkl.10 for ; Wed, 13 Oct 2021 08:58:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=ztuYYF9Onc0ZIjngTVEp2z77n51MjY0wGMZOLwDTwhY=; b=GVq5GFcw/0eVvulNbba6ktlvmE8YFALwpDIhCJ2/vsiC21sLdLoc9O7Xq36D1lJ5lf ZQpif0gOuVc4Y1gCrCxInx9Dy5dbafYfdL55owb7iUdw+pbGb6j7FjBOyhKrHNDwIkvj IUagiUdDR+zKO/Ac9HpWerSCBqwNR3R74jb/oiqdXP39kp5RokKJ70PgYiZ7br199OT/ fxtAXX/51HuCFEYze6DhFLzMABWI4+IwL8WM23aFrRth8DgCQnF6HKbnFhSTNuYZOayb PcC6MbtcinQD4fvigVVSdsAf5MhLy6ddmj2xBzYeMb40ITQkrfyGcy+2NPXD9hI6eXPQ nvgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=ztuYYF9Onc0ZIjngTVEp2z77n51MjY0wGMZOLwDTwhY=; b=GtPwFmAIdYyKGABZfg0LL722VQpcjPBMLsn52heeLWQrYoGYr6PD71s9EwkqCskEjn 9AShWl+x9hUZXmSEI4+mWRBcYoEX8MKJndAh7EEl1flPvP1wyVKewwcg7cWuWgHFnjAT fdhyEn2hpc3uoT2z7is3RXb8sHnudGZnmM2z2fih1z0pu9JTHUGGe1EF36IXUsV3AG97 rP9GM0Bdt3R6eve1ueiS0m2+iPeOCxJxwDDB7Wp3Em4Y1p+VAM23OxbH6Ih9dZW11tAs 2w8x1/B1FMXfhjathW3L7JvTgMYyFVoLEHRFf0fqDja54iuyLcAHgX4GnrfB2FGQqk/b Dfyw== X-Gm-Message-State: AOAM532ugUUwHtxjSAGNfSQ5ys7JuEOP56Sz0lgST69cC3yrPQE2ZjiI Zt4D+59MjcPUDo1iYN1+0nrlYli/mvUe X-Google-Smtp-Source: ABdhPJxp1hUAJxs/riqQe2cYJzZaiMjwH6ehh74ltN5CiIrrR1/FVufG6S8GAC+vFxwjhGJSaTXJSPc9xIJG X-Received: from luke.lon.corp.google.com ([2a00:79e0:d:210:65b5:73d3:1558:b9ae]) (user=qperret job=sendgmr) by 2002:a05:622a:13c6:: with SMTP id p6mr65288qtk.165.1634140730556; Wed, 13 Oct 2021 08:58:50 -0700 (PDT) Date: Wed, 13 Oct 2021 16:58:22 +0100 In-Reply-To: <20211013155831.943476-1-qperret@google.com> Message-Id: <20211013155831.943476-8-qperret@google.com> Mime-Version: 1.0 References: <20211013155831.943476-1-qperret@google.com> X-Mailer: git-send-email 2.33.0.882.g93a45727a2-goog Subject: [PATCH 07/16] KVM: arm64: Refcount hyp stage-1 pgtable pages From: Quentin Perret To: Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Will Deacon , Fuad Tabba , David Brazdil Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To prepare the ground for allowing hyp stage-1 mappings to be removed at run-time, update the KVM page-table code to maintain a correct refcount using the ->{get,put}_page() function callbacks. Signed-off-by: Quentin Perret --- arch/arm64/kvm/hyp/pgtable.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index f8ceebe4982e..768a58835153 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -408,8 +408,10 @@ static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, return false; new = kvm_init_valid_leaf_pte(phys, data->attr, level); - if (hyp_pte_needs_update(old, new)) + if (hyp_pte_needs_update(old, new)) { smp_store_release(ptep, new); + data->mm_ops->get_page(ptep); + } data->phys += granule; return true; @@ -433,6 +435,7 @@ static int hyp_map_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, return -ENOMEM; kvm_set_table_pte(ptep, childp, mm_ops); + mm_ops->get_page(ptep); return 0; } @@ -482,8 +485,16 @@ static int hyp_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, enum kvm_pgtable_walk_flags flag, void * const arg) { struct kvm_pgtable_mm_ops *mm_ops = arg; + kvm_pte_t pte = *ptep; + + if (!kvm_pte_valid(pte)) + return 0; + + mm_ops->put_page(ptep); + + if (kvm_pte_table(pte, level)) + mm_ops->put_page(kvm_pte_follow(pte, mm_ops)); - mm_ops->put_page((void *)kvm_pte_follow(*ptep, mm_ops)); return 0; } @@ -491,7 +502,7 @@ void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt) { struct kvm_pgtable_walker walker = { .cb = hyp_free_walker, - .flags = KVM_PGTABLE_WALK_TABLE_POST, + .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST, .arg = pgt->mm_ops, }; -- 2.33.0.882.g93a45727a2-goog