From patchwork Wed Dec 16 12:28:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yanan Wang X-Patchwork-Id: 11977453 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=-14.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,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 67825C0018C for ; Wed, 16 Dec 2020 12:31:02 +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 EE8A12311B for ; Wed, 16 Dec 2020 12:31:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EE8A12311B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com 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=nVrvM0YqgbNH5Y9b2TNTNM1LasFoc3bOgZ5wLqzJzNA=; b=ZwO7bxV7AcA6T2THvrLlP+EKY Nay+yrjwrW3/CQjN99ekPhUuVh02RHMY4hmZDLBpVmM2dqXaz/7CniMt7QdOMe2qcEnkA4iju1T/1 CYb2yuYUe5f7VuugsSGu0MG6t47uIGWakGMvFQ0CaEzWGgYop5MA1HZuUrRF+eib2Edq4fbYzU97P GVmCXmDHhtrMJYV4xAEesIZrn0eCvtmxL53KvOsn4cmPI6TdwvQDtO7OR836PKir0J+Z2rqwK/7ez xDhI2Or0YzhO2swy99pvIrsFBGNAh0xhX+l+htUkUfMhX9h0c1LiZDm/cUh7n6prG2W7W/cbEXqMs VE9/8TPLw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kpVvX-0004o2-AZ; Wed, 16 Dec 2020 12:29:07 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kpVvS-0004l0-Vb for linux-arm-kernel@lists.infradead.org; Wed, 16 Dec 2020 12:29:05 +0000 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4CwvYK0PSpz15cWD; Wed, 16 Dec 2020 20:28:21 +0800 (CST) Received: from DESKTOP-TMVL5KK.china.huawei.com (10.174.187.128) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.498.0; Wed, 16 Dec 2020 20:28:48 +0800 From: Yanan Wang To: , , Marc Zyngier , Catalin Marinas , Will Deacon , James Morse , "Julien Thierry" , Suzuki K Poulose , Gavin Shan , Quentin Perret Subject: [PATCH v2 1/3] KVM: arm64: Decouple partial code of hyp stage 1 mapping and guest stage 2 mapping Date: Wed, 16 Dec 2020 20:28:42 +0800 Message-ID: <20201216122844.25092-2-wangyanan55@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20201216122844.25092-1-wangyanan55@huawei.com> References: <20201216122844.25092-1-wangyanan55@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.187.128] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201216_072903_650392_233DE75A X-CRM114-Status: GOOD ( 14.99 ) 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: yuzenghui@huawei.com, wanghaibin.wang@huawei.com, Yanan Wang , zhukeqian1@huawei.com, yezengruan@huawei.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Procedures of hyp stage 1 mapping and guest stage 2 mapping are different, but they are tied closely by function kvm_set_valid_leaf_pte(). So separate them by rewriting kvm_set_valid_leaf_pte(). Signed-off-by: Will Deacon Signed-off-by: Yanan Wang --- arch/arm64/kvm/hyp/pgtable.c | 54 ++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 27 deletions(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index bdf8e55ed308..350f9f810930 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -170,10 +170,9 @@ static void kvm_set_table_pte(kvm_pte_t *ptep, kvm_pte_t *childp) smp_store_release(ptep, pte); } -static bool kvm_set_valid_leaf_pte(kvm_pte_t *ptep, u64 pa, kvm_pte_t attr, - u32 level) +static kvm_pte_t kvm_init_valid_leaf_pte(u64 pa, kvm_pte_t attr, u32 level) { - kvm_pte_t old = *ptep, pte = kvm_phys_to_pte(pa); + kvm_pte_t pte = kvm_phys_to_pte(pa); u64 type = (level == KVM_PGTABLE_MAX_LEVELS - 1) ? KVM_PTE_TYPE_PAGE : KVM_PTE_TYPE_BLOCK; @@ -181,12 +180,7 @@ static bool kvm_set_valid_leaf_pte(kvm_pte_t *ptep, u64 pa, kvm_pte_t attr, pte |= FIELD_PREP(KVM_PTE_TYPE, type); pte |= KVM_PTE_VALID; - /* Tolerate KVM recreating the exact same mapping. */ - if (kvm_pte_valid(old)) - return old == pte; - - smp_store_release(ptep, pte); - return true; + return pte; } static int kvm_pgtable_visitor_cb(struct kvm_pgtable_walk_data *data, u64 addr, @@ -341,12 +335,17 @@ static int hyp_map_set_prot_attr(enum kvm_pgtable_prot prot, static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, struct hyp_map_data *data) { + kvm_pte_t new, old = *ptep; u64 granule = kvm_granule_size(level), phys = data->phys; if (!kvm_block_mapping_supported(addr, end, phys, level)) return false; - WARN_ON(!kvm_set_valid_leaf_pte(ptep, phys, data->attr, level)); + /* Tolerate KVM recreating the exact same mapping */ + new = kvm_init_valid_leaf_pte(phys, data->attr, level); + if (old != new && !WARN_ON(kvm_pte_valid(old))) + smp_store_release(ptep, new); + data->phys += granule; return true; } @@ -465,27 +464,29 @@ static bool stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, struct stage2_map_data *data) { + kvm_pte_t new, old = *ptep; u64 granule = kvm_granule_size(level), phys = data->phys; + struct page *page = virt_to_page(ptep); if (!kvm_block_mapping_supported(addr, end, phys, level)) return false; - /* - * If the PTE was already valid, drop the refcount on the table - * early, as it will be bumped-up again in stage2_map_walk_leaf(). - * This ensures that the refcount stays constant across a valid to - * valid PTE update. - */ - if (kvm_pte_valid(*ptep)) - put_page(virt_to_page(ptep)); + new = kvm_init_valid_leaf_pte(phys, data->attr, level); + if (kvm_pte_valid(old)) { + /* Tolerate KVM recreating the exact same mapping */ + if (old == new) + goto out; - if (kvm_set_valid_leaf_pte(ptep, phys, data->attr, level)) - goto out; + /* There's an existing different valid leaf entry, so perform + * break-before-make. + */ + kvm_set_invalid_pte(ptep); + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level); + put_page(page); + } - /* There's an existing valid leaf entry, so perform break-before-make */ - kvm_set_invalid_pte(ptep); - kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level); - kvm_set_valid_leaf_pte(ptep, phys, data->attr, level); + smp_store_release(ptep, new); + get_page(page); out: data->phys += granule; return true; @@ -527,7 +528,7 @@ static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, } if (stage2_map_walker_try_leaf(addr, end, level, ptep, data)) - goto out_get_page; + return 0; if (WARN_ON(level == KVM_PGTABLE_MAX_LEVELS - 1)) return -EINVAL; @@ -551,9 +552,8 @@ static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, } kvm_set_table_pte(ptep, childp); - -out_get_page: get_page(page); + return 0; }