From patchwork Tue Jun 16 09:35:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: zhukeqian X-Patchwork-Id: 11606963 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A8C1914DD for ; Tue, 16 Jun 2020 09:36:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9A8DB20842 for ; Tue, 16 Jun 2020 09:36:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728294AbgFPJgR (ORCPT ); Tue, 16 Jun 2020 05:36:17 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:6335 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728243AbgFPJgQ (ORCPT ); Tue, 16 Jun 2020 05:36:16 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 9F912D563F9CEB625A78; Tue, 16 Jun 2020 17:36:13 +0800 (CST) Received: from DESKTOP-5IS4806.china.huawei.com (10.173.221.230) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.487.0; Tue, 16 Jun 2020 17:36:06 +0800 From: Keqian Zhu To: , , , CC: Catalin Marinas , Marc Zyngier , James Morse , Will Deacon , "Suzuki K Poulose" , Sean Christopherson , Julien Thierry , Mark Brown , "Thomas Gleixner" , Andrew Morton , Alexios Zavras , , , , Keqian Zhu Subject: [PATCH 03/12] KVM: arm64: Report hardware dirty status of stage2 PTE if coverred Date: Tue, 16 Jun 2020 17:35:44 +0800 Message-ID: <20200616093553.27512-4-zhukeqian1@huawei.com> X-Mailer: git-send-email 2.8.4.windows.1 In-Reply-To: <20200616093553.27512-1-zhukeqian1@huawei.com> References: <20200616093553.27512-1-zhukeqian1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.173.221.230] X-CFilter-Loop: Reflected Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org kvm_set_pte is called to replace a target PTE with a desired one. We always do this without changing the desired one, but if dirty status set by hardware is coverred, let caller know it. Signed-off-by: Keqian Zhu --- arch/arm64/kvm/mmu.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 5ad87bce23c0..27407153121b 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -194,11 +194,45 @@ static void clear_stage2_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr put_page(virt_to_page(pmd)); } -static inline void kvm_set_pte(pte_t *ptep, pte_t new_pte) +#ifdef CONFIG_ARM64_HW_AFDBM +/** + * @ret: true if dirty status set by hardware is coverred. + */ +static bool kvm_set_pte(pte_t *ptep, pte_t new_pte) +{ + pteval_t old_pteval, new_pteval, pteval; + bool old_logging, new_no_write; + + old_logging = kvm_hw_dbm_enabled() && !pte_none(*ptep) && + kvm_s2pte_dbm(ptep); + new_no_write = pte_none(new_pte) || kvm_s2pte_readonly(&new_pte); + + if (!old_logging || !new_no_write) { + WRITE_ONCE(*ptep, new_pte); + dsb(ishst); + return false; + } + + new_pteval = pte_val(new_pte); + pteval = READ_ONCE(pte_val(*ptep)); + do { + old_pteval = pteval; + pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, new_pteval); + } while (pteval != old_pteval); + + return !kvm_s2pte_readonly(&__pte(pteval)); +} +#else +/** + * @ret: true if dirty status set by hardware is coverred. + */ +static inline bool kvm_set_pte(pte_t *ptep, pte_t new_pte) { WRITE_ONCE(*ptep, new_pte); dsb(ishst); + return false; } +#endif /* CONFIG_ARM64_HW_AFDBM */ static inline void kvm_set_pmd(pmd_t *pmdp, pmd_t new_pmd) {