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=-5.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 D580BC2D0A8 for ; Mon, 28 Sep 2020 08:18:36 +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 778ED20738 for ; Mon, 28 Sep 2020 08:18:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="pQeZFN5e" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 778ED20738 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kMoMR-000508-MO; Mon, 28 Sep 2020 08:18:15 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kMoMP-000503-TX for xen-devel@lists.xenproject.org; Mon, 28 Sep 2020 08:18:13 +0000 X-Inumbo-ID: 6f39a702-2726-4b95-90ec-b37b73ae88dc Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 6f39a702-2726-4b95-90ec-b37b73ae88dc; Mon, 28 Sep 2020 08:18:12 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1601281092; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yDaS79HIkKSC1oB88t4NzWG1CHqraOGj7iV+uwhKiRk=; b=pQeZFN5e5q02C+5mi9/qaZmCIN59lqU8J4dQ5cE6EPVI0PHNtTUx0RHC8nk1X7eOXe+PPf j0vjEAl25ckYVrbvolHxZuH007kI+KpkecNXIK3fo27hviTt63SvgVwNN13iM8h/lXI/aN DbeEfvAqjvY/avSoW0r9RQi8tnfGgws= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id F3B47B1A9; Mon, 28 Sep 2020 08:18:11 +0000 (UTC) Subject: Re: [PATCH 1/4] xen/acpi: Rework acpi_os_map_memory() and acpi_os_unmap_memory() To: Julien Grall Cc: xen-devel@lists.xenproject.org, alex.bennee@linaro.org, masami.hiramatsu@linaro.org, ehem+xen@m5p.com, bertrand.marquis@arm.com, andre.przywara@arm.com, Julien Grall , Stefano Stabellini , Volodymyr Babchuk , Andrew Cooper , George Dunlap , Ian Jackson , Wei Liu , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= References: <20200926205542.9261-1-julien@xen.org> <20200926205542.9261-2-julien@xen.org> From: Jan Beulich Message-ID: Date: Mon, 28 Sep 2020 10:18:10 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200926205542.9261-2-julien@xen.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On 26.09.2020 22:55, Julien Grall wrote: > @@ -49,6 +53,12 @@ char *__acpi_map_table(paddr_t phys, unsigned long size) > return ((char *) base + offset); > } > > +bool __acpi_unmap_table(void *ptr, unsigned long size) > +{ > + return ( vaddr >= FIXMAP_ADDR(FIXMAP_ACPI_BEGIN) && > + vaddr < (FIXMAP_ADDR(FIXMAP_ACPI_END) + PAGE_SIZE) ); Nit: If this wasn't Arm code, I'd ask for the parentheses to be dropped altogether, but at least the stray blanks should go away imo. > --- a/xen/arch/x86/acpi/lib.c > +++ b/xen/arch/x86/acpi/lib.c > @@ -46,6 +46,10 @@ char *__acpi_map_table(paddr_t phys, unsigned long size) > if ((phys + size) <= (1 * 1024 * 1024)) > return __va(phys); > > + /* No arch specific implementation after early boot */ > + if (system_state >= SYS_STATE_boot) > + return NULL; Considering the code in context above, the comment isn't entirely correct. > @@ -66,6 +70,20 @@ char *__acpi_map_table(paddr_t phys, unsigned long size) > return ((char *) base + offset); > } > > +bool __acpi_unmap_table(void *ptr, unsigned long size) Is there anything standing in the way of making ptr "const void *"? > +{ > + unsigned long vaddr = (unsigned long)ptr; > + > + if (vaddr >= DIRECTMAP_VIRT_START && > + vaddr < DIRECTMAP_VIRT_END) { > + ASSERT(!((__pa(ptr) + size - 1) >> 20)); > + return true; > + } > + > + return (vaddr >= __fix_to_virt(FIX_ACPI_END)) && > + (vaddr < (__fix_to_virt(FIX_ACPI_BEGIN) + PAGE_SIZE)); Indentation is slightly wrong here. Also please consider reducing the number of parentheses here; at the very least the return and the earlier if() want to be consistent in when ones are(n't) used. > --- a/xen/drivers/acpi/osl.c > +++ b/xen/drivers/acpi/osl.c > @@ -92,27 +92,29 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) > void __iomem * > acpi_os_map_memory(acpi_physical_address phys, acpi_size size) > { > - if (system_state >= SYS_STATE_boot) { > - mfn_t mfn = _mfn(PFN_DOWN(phys)); > - unsigned int offs = phys & (PAGE_SIZE - 1); > - > - /* The low first Mb is always mapped on x86. */ > - if (IS_ENABLED(CONFIG_X86) && !((phys + size - 1) >> 20)) > - return __va(phys); > - return __vmap(&mfn, PFN_UP(offs + size), 1, 1, > - ACPI_MAP_MEM_ATTR, VMAP_DEFAULT) + offs; > - } > - return __acpi_map_table(phys, size); > + void *ptr; > + mfn_t mfn = _mfn(PFN_DOWN(phys)); > + unsigned int offs = phys & (PAGE_SIZE - 1); Open-coding PAGE_OFFSET()? > + /* Try the arch specific implementation first */ > + ptr = __acpi_map_table(phys, size); > + if (ptr) > + return ptr; > + > + /* No common implementation for early boot map */ > + if (unlikely(system_state < SYS_STATE_boot)) > + return NULL; Consistently hard tabs for indentation here, please. > + ptr = __vmap(&mfn, PFN_UP(offs + size), 1, 1, > + ACPI_MAP_MEM_ATTR, VMAP_DEFAULT); > + > + return !ptr ? NULL : (ptr + offs); Slightly odd that you don't let the success case go first, the more that it's minimally shorter: return ptr ? ptr + offs : NULL; Jan