From patchwork Thu Dec 9 20:05:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksandr Tyshchenko X-Patchwork-Id: 12668219 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0C7A9C4321E for ; Thu, 9 Dec 2021 20:06:05 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.243310.420900 (Exim 4.92) (envelope-from ) id 1mvPfm-00053k-9t; Thu, 09 Dec 2021 20:05:46 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 243310.420900; Thu, 09 Dec 2021 20:05:46 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mvPfm-00052l-5i; Thu, 09 Dec 2021 20:05:46 +0000 Received: by outflank-mailman (input) for mailman id 243310; Thu, 09 Dec 2021 20:05:45 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mvPfl-0004Xd-7o for xen-devel@lists.xenproject.org; Thu, 09 Dec 2021 20:05:45 +0000 Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [2a00:1450:4864:20::229]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 6416bcb1-592b-11ec-a831-37629979565c; Thu, 09 Dec 2021 21:05:44 +0100 (CET) Received: by mail-lj1-x229.google.com with SMTP id 207so10646554ljf.10 for ; Thu, 09 Dec 2021 12:05:44 -0800 (PST) Received: from otyshchenko.router ([212.22.223.21]) by smtp.gmail.com with ESMTPSA id o12sm87371lft.134.2021.12.09.12.05.42 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 09 Dec 2021 12:05:42 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 6416bcb1-592b-11ec-a831-37629979565c DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=XoEU3DaXUqalCs6jzwcHq5Z2kR7REX3RsrqKMfGCo2w=; b=GlM2t+eQRjThRQMjBZpSdxLnDWzEbjJWVwRDusOaEx3MeX4FketF3biTqFzeEnAVU0 VhfKGEcuQp52HiEpPpvacBbuQwd87JvMTehJYvdAXf7KeOioUXb3WO3fCLID1qKZ7UBZ UTgdjk7vrs0SFE8l7HuLKFHyLrmDTcAD9cNMgKBWyA2U3xnLfBw1azVxQh+7gf79/OoO 1dQ4RbzOz6pbkTfeB0WK3PC7JrQpMMkPLByBqimCV2s9g1epLNijcmYesEuTP320tf69 StZYm2luPMAgllAQQSpglOUobSo4Wx1O+YEknSkfIltx1nSkiZfvAJ+J+cQWzBjsQ1vZ FzVg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=XoEU3DaXUqalCs6jzwcHq5Z2kR7REX3RsrqKMfGCo2w=; b=2gsRIBCqHKT/MQJ+AGEqyzsUvN9ndHp/Ghtd1RPgTS7CJGvbWPMBnEnL5xedea/719 J8sbIBqCBWni2jUjFMkeM9Lxopj49/uxDWNJlyEko8HwAjd6wo7BIDhHfNtC8MQaUBlZ ONdGtsObBQnj01OWF+Wd2EU9Jh7qFfyZ4r/byzznVkGvvqGYJOUDDd0IgcJYsaARLKji JT5jdqR4irb2XyMmj29cJSZ/8KQnCh7nfujNNOosWzXiMgkDhbJiVML3dGHLh3tYWo46 E/LyPzijMDwkla9U/6WI4fEldfmrXHoEocPkjjoqDSFJZKjlR9SK0c7kmDzdsMbeVAFK hY1Q== X-Gm-Message-State: AOAM5327OMK+6wQKZFXiuTHSMfhwoXlXrLrJ5x0veBDttf7PMoQS+XI3 oJYrwS67kITD5znvQ44PRO4A9NSicNvKPw== X-Google-Smtp-Source: ABdhPJwRwGnN2HYDLn4/ya4vANtMy2LFN1OiYbe33DChi+j/uEDELzNOeHtrWCUSzf5Mr+Zxr7NNrA== X-Received: by 2002:a2e:8ec7:: with SMTP id e7mr8517097ljl.430.1639080343851; Thu, 09 Dec 2021 12:05:43 -0800 (PST) From: Oleksandr Tyshchenko To: xen-devel@lists.xenproject.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Oleksandr Tyshchenko , Stefano Stabellini , Russell King , Julien Grall Subject: [PATCH V4 2/6] arm/xen: Switch to use gnttab_setup_auto_xlat_frames() for DT Date: Thu, 9 Dec 2021 22:05:32 +0200 Message-Id: <1639080336-26573-3-git-send-email-olekstysh@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1639080336-26573-1-git-send-email-olekstysh@gmail.com> References: <1639080336-26573-1-git-send-email-olekstysh@gmail.com> From: Oleksandr Tyshchenko Read the start address of the grant table space from DT (region 0). This patch mostly restores behaviour before commit 3cf4095d7446 ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") but trying not to break the ACPI support added after that commit. So the patch touches DT part only and leaves the ACPI part with xen_xlate_map_ballooned_pages(). Also in order to make a code more resilient use a fallback to xen_xlate_map_ballooned_pages() if grant table region wasn't found. This is a preparation for using Xen extended region feature where unused regions of guest physical address space (provided by the hypervisor) will be used to create grant/foreign/whatever mappings instead of wasting real RAM pages from the domain memory for establishing these mappings. The immediate benefit of this change: - Avoid superpage shattering in Xen P2M when establishing stage-2 mapping (GFN <-> MFN) for the grant table space - Avoid wasting real RAM pages (reducing the amount of memory usuable) for mapping grant table space - The grant table space is always mapped at the exact same place (region 0 is reserved for the grant table) Signed-off-by: Oleksandr Tyshchenko Reviewed-by: Stefano Stabellini --- Changes RFC -> V2: - new patch Changes V2 -> V3: - add __read_mostly specifier to xen_grant_frames - retain a fallback to xen_xlate_map_ballooned_pages() if xen_grant_frames is invalid - process xen_events_irq before xen_grant_frames in xen_dt_guest_init() - update patch description Changes V3 -> V4: - add Stefano's R-b - remove first condition in "if (!acpi_disabled || !xen_grant_frames)" --- arch/arm/xen/enlighten.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 7619fbf..49bb675 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -59,6 +59,9 @@ unsigned long xen_released_pages; struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; static __read_mostly unsigned int xen_events_irq; +static __read_mostly phys_addr_t xen_grant_frames; + +#define GRANT_TABLE_INDEX 0 uint32_t xen_start_flags; EXPORT_SYMBOL(xen_start_flags); @@ -303,6 +306,7 @@ static void __init xen_acpi_guest_init(void) static void __init xen_dt_guest_init(void) { struct device_node *xen_node; + struct resource res; xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); if (!xen_node) { @@ -311,13 +315,19 @@ static void __init xen_dt_guest_init(void) } xen_events_irq = irq_of_parse_and_map(xen_node, 0); + + if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { + pr_err("Xen grant table region is not found\n"); + return; + } + xen_grant_frames = res.start; } static int __init xen_guest_init(void) { struct xen_add_to_physmap xatp; struct shared_info *shared_info_page = NULL; - int cpu; + int rc, cpu; if (!xen_domain()) return 0; @@ -370,12 +380,16 @@ static int __init xen_guest_init(void) for_each_possible_cpu(cpu) per_cpu(xen_vcpu_id, cpu) = cpu; - xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); - if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, - &xen_auto_xlat_grant_frames.vaddr, - xen_auto_xlat_grant_frames.count)) { + if (!xen_grant_frames) { + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); + rc = xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, + &xen_auto_xlat_grant_frames.vaddr, + xen_auto_xlat_grant_frames.count); + } else + rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); + if (rc) { free_percpu(xen_vcpu_info); - return -ENOMEM; + return rc; } gnttab_init();