From patchwork Tue Oct 26 16:05:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksandr Tyshchenko X-Patchwork-Id: 12585103 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 53FC4C433FE for ; Tue, 26 Oct 2021 16:08:00 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 0E3B660EB9 for ; Tue, 26 Oct 2021 16:08:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0E3B660EB9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.216514.376151 (Exim 4.92) (envelope-from ) id 1mfOzL-00025v-A5; Tue, 26 Oct 2021 16:07:47 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 216514.376151; Tue, 26 Oct 2021 16:07:47 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mfOzL-00025m-6F; Tue, 26 Oct 2021 16:07:47 +0000 Received: by outflank-mailman (input) for mailman id 216514; Tue, 26 Oct 2021 16:07:46 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1mfOzK-0001p4-8v for xen-devel@lists.xenproject.org; Tue, 26 Oct 2021 16:07:46 +0000 Received: from mail-ed1-x535.google.com (unknown [2a00:1450:4864:20::535]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id c03a9faa-4501-4e50-b60a-a149519fe8d0; Tue, 26 Oct 2021 16:07:42 +0000 (UTC) Received: by mail-ed1-x535.google.com with SMTP id h7so4689051ede.8 for ; Tue, 26 Oct 2021 09:07:42 -0700 (PDT) Received: from otyshchenko.router ([212.22.223.21]) by smtp.gmail.com with ESMTPSA id eu9sm4025195ejc.14.2021.10.26.09.05.21 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 26 Oct 2021 09:05:22 -0700 (PDT) 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: c03a9faa-4501-4e50-b60a-a149519fe8d0 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=wgCQ3QpgBU+9Jo1johQyA8YH17F0xtomZ9AsDb/n0+k=; b=ErjQU0xF7MucZPckHXbirk+HxNHRkSp0ftkyRu6h2iwOhEb1+8lpFeakKm96+M1vrt vbgqEK316lrbPhq56wyunZz1slXFzySXAHjpl7l2X1RylcVS5UjbXcavz+df5VluZeo5 rhqg08YnA4j2D0jcYNVpA0/aT3jPn+lsaOITDNiwlSeIGHChg+T/kdFrahVXgd0v5QnV b/7SP50ygKAhav42t9BKm78sXv9KGYT1kZ6ZI3AN/0kEHd2F7FnWdty0PGISoNyIfYQW 1GEU778jvDLC9NnLu992kgqal847kKCrc3m3R2RYsoFeXGhbY9qA+qG+EkMzLsJsrCVR lVJQ== 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=wgCQ3QpgBU+9Jo1johQyA8YH17F0xtomZ9AsDb/n0+k=; b=uY9AiCrvZFyNS1GjmsyuQ0CuDPsyH+5m06uA7s/UHYEVevAD801C8NU352hBe4Oeba 7+5PAhMLIL29L+vT5+DcdpNtT7FXiQWCaG1rEaI9zaSfdB+7owRTMMT8SuXpxfhTz+Gc zpzKQ++3T1jqalGlVqrcRODuzwhrqsdjaBXIhNjSkVOWGS+6onJb8AUWFto7dgn7ZmrX u5goqJXGiBOcIdv6ARKZc5ax8o7khXjw33ch+T+LF9z6DFvDkl1fUppAqbCb3FqiZ5gY 6qzbSDn2pRrUXBYZCI0mOHT+f4kQW6Wc721duDJNgIQyXX+cUe2TNcXWy+XLA6Mxpm54 Noiw== X-Gm-Message-State: AOAM533AtyyNT33ERFcOygFTt6T+UT9NxjheSf5uWwdwjUW/7UfBpsuz iCOfZ+UClyfjRSNq7wcomqZiE471Z3E= X-Google-Smtp-Source: ABdhPJxHzSGaUiizFl6ReNX7rAoYCSY51GxR2/K5Ko9EJMbZTxjP/iW8YNrB1UrUQguQ3zP8KNzhvg== X-Received: by 2002:a05:6402:190e:: with SMTP id e14mr37063692edz.20.1635264322584; Tue, 26 Oct 2021 09:05:22 -0700 (PDT) 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 , Boris Ostrovsky , Juergen Gross , Julien Grall Subject: [PATCH V2 4/4] arm/xen: Read extended regions from DT and init Xen resource Date: Tue, 26 Oct 2021 19:05:12 +0300 Message-Id: <1635264312-3796-5-git-send-email-olekstysh@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1635264312-3796-1-git-send-email-olekstysh@gmail.com> References: <1635264312-3796-1-git-send-email-olekstysh@gmail.com> From: Oleksandr Tyshchenko This patch implements arch_xen_unpopulated_init() on Arm where the extended regions (if any) are gathered from DT and inserted into passed Xen resource to be used as unused address space for Xen scratch pages by unpopulated-alloc code. The extended region (safe range) is a region of guest physical address space which is unused and could be safely used to create grant/foreign mappings instead of wasting real RAM pages from the domain memory for establishing these mappings. The extended regions are chosen by the hypervisor at the domain creation time and advertised to it via "reg" property under hypervisor node in the guest device-tree. As region 0 is reserved for grant table space (always present), the indexes for extended regions are 1...N. If arch_xen_unpopulated_init() fails for some reason the default behaviour will be restored (allocate xenballooned pages). This patch also removes XEN_UNPOPULATED_ALLOC dependency on x86. Signed-off-by: Oleksandr Tyshchenko --- Changes RFC -> V2: - new patch, instead of "[RFC PATCH 2/2] xen/unpopulated-alloc: Query hypervisor to provide unallocated space" --- arch/arm/xen/enlighten.c | 112 +++++++++++++++++++++++++++++++++++++++++++++++ drivers/xen/Kconfig | 2 +- 2 files changed, 113 insertions(+), 1 deletion(-) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index dea46ec..1a1e0d3 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -62,6 +62,7 @@ static __read_mostly unsigned int xen_events_irq; static phys_addr_t xen_grant_frames; #define GRANT_TABLE_INDEX 0 +#define EXT_REGION_INDEX 1 uint32_t xen_start_flags; EXPORT_SYMBOL(xen_start_flags); @@ -303,6 +304,117 @@ static void __init xen_acpi_guest_init(void) #endif } +#ifdef CONFIG_XEN_UNPOPULATED_ALLOC +int arch_xen_unpopulated_init(struct resource *res) +{ + struct device_node *np; + struct resource *regs, *tmp_res; + uint64_t min_gpaddr = -1, max_gpaddr = 0; + unsigned int i, nr_reg = 0; + struct range mhp_range; + int rc; + + if (!xen_domain()) + return -ENODEV; + + np = of_find_compatible_node(NULL, NULL, "xen,xen"); + if (WARN_ON(!np)) + return -ENODEV; + + /* Skip region 0 which is reserved for grant table space */ + while (of_get_address(np, nr_reg + EXT_REGION_INDEX, NULL, NULL)) + nr_reg++; + + if (!nr_reg) { + pr_err("No extended regions are found\n"); + return -EINVAL; + } + + regs = kcalloc(nr_reg, sizeof(*regs), GFP_KERNEL); + if (!regs) + return -ENOMEM; + + /* + * Create resource from extended regions provided by the hypervisor to be + * used as unused address space for Xen scratch pages. + */ + for (i = 0; i < nr_reg; i++) { + rc = of_address_to_resource(np, i + EXT_REGION_INDEX, ®s[i]); + if (rc) + goto err; + + if (max_gpaddr < regs[i].end) + max_gpaddr = regs[i].end; + if (min_gpaddr > regs[i].start) + min_gpaddr = regs[i].start; + } + + /* Check whether the resource range is within the hotpluggable range */ + mhp_range = mhp_get_pluggable_range(true); + if (min_gpaddr < mhp_range.start) + min_gpaddr = mhp_range.start; + if (max_gpaddr > mhp_range.end) + max_gpaddr = mhp_range.end; + + res->start = min_gpaddr; + res->end = max_gpaddr; + + /* + * Mark holes between extended regions as unavailable. The rest of that + * address space will be available for the allocation. + */ + for (i = 1; i < nr_reg; i++) { + resource_size_t start, end; + + start = regs[i - 1].end + 1; + end = regs[i].start - 1; + + if (start > (end + 1)) { + rc = -EINVAL; + goto err; + } + + /* There is no hole between regions */ + if (start == (end + 1)) + continue; + + /* Check whether the hole range is within the resource range */ + if (start < res->start || end > res->end) { + if (start < res->start) + start = res->start; + if (end > res->end) + end = res->end; + + if (start >= (end + 1)) + continue; + } + + tmp_res = kzalloc(sizeof(*tmp_res), GFP_KERNEL); + if (!tmp_res) { + rc = -ENOMEM; + goto err; + } + + tmp_res->name = "Unavailable space"; + tmp_res->start = start; + tmp_res->end = end; + + rc = insert_resource(res, tmp_res); + if (rc) { + pr_err("Cannot insert resource [%llx - %llx] %d\n", + tmp_res->start, tmp_res->end, rc); + kfree(tmp_res); + goto err; + } + } + +err: + kfree(regs); + + return rc; +} +#endif + static void __init xen_dt_guest_init(void) { struct device_node *xen_node; diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 1b2c3ac..e6031fc 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -297,7 +297,7 @@ config XEN_FRONT_PGDIR_SHBUF config XEN_UNPOPULATED_ALLOC bool "Use unpopulated memory ranges for guest mappings" - depends on X86 && ZONE_DEVICE + depends on ZONE_DEVICE default XEN_BACKEND || XEN_GNTDEV || XEN_DOM0 help Use unpopulated memory ranges in order to create mappings for guest