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=-15.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 3A08AC07E95 for ; Tue, 20 Jul 2021 14:00:24 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 F305A6113A for ; Tue, 20 Jul 2021 14:00:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F305A6113A Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.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=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BFz46db+uy8h0ru97h6lE0aEnlZUJdaNHgSMRVm5nUM=; b=u9wI2h4pB3myer qkPluxv0qQ5aTzZ8SMWRKZAZYoCx4VOv7V4b84nofUpbiJmSKrLzZbcH4aNl6bZ83rhit38f3/nB0 qZBLEaRgsXNQrNLkpl7I16lT/PeXBKkgbapIXJdfEY61chPuYUHoPB7R0F3RSa9JVs7yeo3dcluuq CX2TV9LawJOecVVamV5WNLBXARyYktz5dr8W0e460GCblc1eXb7QTdsRUzQ2LjdYqgs+Bxd6VwOng 7St32ywiPdQpSQYRT1X47etBM4InhQwnChn2G5D481uX9MyHzQXq9CfeCjZxfVbaehf2o/pbDH360 9CZir1jL7GSexV9tTJSQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m5qG7-00D3Qf-2y; Tue, 20 Jul 2021 13:58:07 +0000 Received: from mail-oi1-x236.google.com ([2607:f8b0:4864:20::236]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1m5qFx-00D3OS-41 for linux-arm-kernel@lists.infradead.org; Tue, 20 Jul 2021 13:57:59 +0000 Received: by mail-oi1-x236.google.com with SMTP id h9so24597435oih.4 for ; Tue, 20 Jul 2021 06:57:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=z54CTZ7m1ybOAaQslMS3Yzi7pwB2B73X0p7oLSu85mA=; b=RoH7jW88EdEt7Zcg9ZAb1d4Bp5ahB/RWZA0yBQYnLk8mVoTqhNfvVkxPYb5ejv86Gy 4T4vuSwRZi9fabkvECsfWgswUgwFGZBdRmDUmF3jjLIMbrFlpX60Ra3slAseSlqOc8gT wQTG+OAT0P0Ue9KVpTNUoikCqkex3E0sr3nWPog/XK/t+6g/E3GIPtZQUiDecQ9u2Rms 9+jRIZ4eiWxhM/1hhVvcz63NYSQovi+AQeGs9ilkvM7hYiWJ2o/Jr2Ft7S3tmviu/Tnn kluG2NVyuOHWY3GXx6uErJwdt1d0NLeSviJ/nrHi50LyNstUOzp3NaBq4ydzGjt0GHSe Fxyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=z54CTZ7m1ybOAaQslMS3Yzi7pwB2B73X0p7oLSu85mA=; b=Jh5r7a6gSi9tIhrfll/GVA4pcrzwpiA1xvrWTecqIZddNFrtZwKD2CkRbrjYgeCLwu kzaLkJrUYqsrIhTs+LOQHppJfIdWzvbX4EwNfMLkloB9CH76qd9mK0rW0KV7x7kDUZUi 4Lkjv7jwiUsD1sASCq/kh7hAE2iW9b/lVX0K4Bgs0A/OLsWsjOjXLAg+VxW8I5a9djNb /Kcz6v28XG7wv8Wm705raV+X/+7LRnm8AIP1SBKUmozhoBuv3Czgyg7a1jcVN1iAFRvk cr9wBUjuvr1R5fPNxmU0wzezPEFdUd7QhvWRG565gCkvWjkpS/5xYG0MrO7jyrJuJyQP 7YFw== X-Gm-Message-State: AOAM530t3pyDtqKyZ52r9U54Ru0/VPyJMuT8hSo1Pj62eeO5KWSnH12C z0nkEQxPJm7fYOYXyHHD+mwhuinMIy+2D2zVOGIiWQ== X-Google-Smtp-Source: ABdhPJxkbl1jK/kwdgT8I4sKUxzm7eCYwuuEYGAnfVuHj/oT/zlMVBdDpQ6GDUnClK1MlQCp3VfruvMZU3I7IwoRwHY= X-Received: by 2002:aca:cf8e:: with SMTP id f136mr25218634oig.67.1626789475645; Tue, 20 Jul 2021 06:57:55 -0700 (PDT) MIME-Version: 1.0 References: <20210719104735.3681732-1-qperret@google.com> <20210719104735.3681732-2-qperret@google.com> In-Reply-To: <20210719104735.3681732-2-qperret@google.com> From: Fuad Tabba Date: Tue, 20 Jul 2021 14:57:19 +0100 Message-ID: Subject: Re: [PATCH 01/14] KVM: arm64: Provide the host_stage2_try() helper macro To: Quentin Perret Cc: maz@kernel.org, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, ardb@kernel.org, qwandor@google.com, dbrazdil@google.com, kernel-team@android.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210720_065757_239118_CF508A42 X-CRM114-Status: GOOD ( 26.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Hi Quentin, On Mon, Jul 19, 2021 at 11:47 AM Quentin Perret wrote: > > We currently unmap all MMIO mappings from the host stage-2 to recycle > the pages whenever we run out. In order to make this pattern easy to > re-use from other places, factor the logic out into a dedicated macro. > While at it, apply the macro for the kvm_pgtable_stage2_set_owner() > calls. They're currently only called early on and are guaranteed to > succeed, but making them robust to the -ENOMEM case doesn't hurt and > will avoid painful debugging sessions later on. > > Signed-off-by: Quentin Perret > --- > arch/arm64/kvm/hyp/nvhe/mem_protect.c | 38 ++++++++++++++------------- > 1 file changed, 20 insertions(+), 18 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c > index d938ce95d3bd..56f2117c877b 100644 > --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c > +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c > @@ -208,6 +208,23 @@ static inline int __host_stage2_idmap(u64 start, u64 end, > prot, &host_s2_pool); > } > > +/* > + * The pool has been provided with enough pages to cover all of memory with > + * page granularity, but it is difficult to know how much of the MMIO range > + * we will need to cover upfront, so we may need to 'recycle' the pages if we > + * run out. > + */ > +#define host_stage2_try(fn, ...) \ > + ({ \ > + int __ret = fn(__VA_ARGS__); \ > + if (__ret == -ENOMEM) { \ > + __ret = host_stage2_unmap_dev_all(); \ > + if (!__ret) \ > + __ret = fn(__VA_ARGS__); \ > + } \ > + __ret; \ > + }) I think it might be good to document that this macro expects the host_kvm.lock to be held. Thanks, /fuad > static int host_stage2_idmap(u64 addr) > { > enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R | KVM_PGTABLE_PROT_W; > @@ -223,22 +240,7 @@ static int host_stage2_idmap(u64 addr) > if (ret) > goto unlock; > > - ret = __host_stage2_idmap(range.start, range.end, prot); > - if (ret != -ENOMEM) > - goto unlock; > - > - /* > - * The pool has been provided with enough pages to cover all of memory > - * with page granularity, but it is difficult to know how much of the > - * MMIO range we will need to cover upfront, so we may need to 'recycle' > - * the pages if we run out. > - */ > - ret = host_stage2_unmap_dev_all(); > - if (ret) > - goto unlock; > - > - ret = __host_stage2_idmap(range.start, range.end, prot); > - > + ret = host_stage2_try(__host_stage2_idmap, range.start, range.end, prot); > unlock: > hyp_spin_unlock(&host_kvm.lock); > > @@ -257,8 +259,8 @@ int __pkvm_mark_hyp(phys_addr_t start, phys_addr_t end) > return -EINVAL; > > hyp_spin_lock(&host_kvm.lock); > - ret = kvm_pgtable_stage2_set_owner(&host_kvm.pgt, start, end - start, > - &host_s2_pool, pkvm_hyp_id); > + ret = host_stage2_try(kvm_pgtable_stage2_set_owner, &host_kvm.pgt, > + start, end - start, &host_s2_pool, pkvm_hyp_id); > hyp_spin_unlock(&host_kvm.lock); > > return ret != -EAGAIN ? ret : 0; > -- > 2.32.0.402.g57bb445576-goog > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel