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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B9644C2D0DB for ; Fri, 24 Jan 2020 17:10:11 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 72D9720704 for ; Fri, 24 Jan 2020 17:10:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 72D9720704 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4845HP3LcvzDqg1 for ; Sat, 25 Jan 2020 04:10:09 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=aneesh.kumar@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4845DM5jTTzDqjV for ; Sat, 25 Jan 2020 04:07:31 +1100 (AEDT) Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00OH5xma109424 for ; Fri, 24 Jan 2020 12:07:28 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2xq3ma5vp7-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 24 Jan 2020 12:07:28 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 24 Jan 2020 17:07:23 -0000 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 00OH7Mv723265404 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 24 Jan 2020 17:07:22 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3E88042047; Fri, 24 Jan 2020 17:07:22 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E9FB042045; Fri, 24 Jan 2020 17:07:20 +0000 (GMT) Received: from [9.85.89.94] (unknown [9.85.89.94]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 24 Jan 2020 17:07:20 +0000 (GMT) Subject: Re: [PATCH v4 1/6] libnvdimm/namespace: Make namespace size validation arch dependent To: Dan Williams References: <20200120140749.69549-1-aneesh.kumar@linux.ibm.com> <20200120140749.69549-2-aneesh.kumar@linux.ibm.com> <5fd11235-5f26-b10a-140f-ef24214c85b1@linux.ibm.com> From: "Aneesh Kumar K.V" Date: Fri, 24 Jan 2020 22:37:19 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 20012417-0020-0000-0000-000003A3AE9F X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20012417-0021-0000-0000-000021FB4D1E Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-01-24_06:2020-01-24, 2020-01-24 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 phishscore=0 mlxlogscore=778 mlxscore=0 adultscore=0 clxscore=1015 priorityscore=1501 malwarescore=0 lowpriorityscore=0 spamscore=0 impostorscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001240140 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vishal L Verma , jmoyer , linuxppc-dev@lists.ozlabs.org, linux-nvdimm Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 1/24/20 10:15 PM, Dan Williams wrote: > On Thu, Jan 23, 2020 at 11:34 PM Aneesh Kumar K.V > wrote: >> >> On 1/24/20 11:27 AM, Dan Williams wrote: >>> On Mon, Jan 20, 2020 at 6:08 AM Aneesh Kumar K.V >>> >> >> .... >> >>>> >>>> +unsigned long arch_namespace_map_size(void) >>>> +{ >>>> + return PAGE_SIZE; >>>> +} >>>> +EXPORT_SYMBOL_GPL(arch_namespace_map_size); >>>> + >>>> + >>>> static void __cpa_flush_all(void *arg) >>>> { >>>> unsigned long cache = (unsigned long)arg; >>>> diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h >>>> index 9df091bd30ba..a3476dbd2656 100644 >>>> --- a/include/linux/libnvdimm.h >>>> +++ b/include/linux/libnvdimm.h >>>> @@ -284,4 +284,5 @@ static inline void arch_invalidate_pmem(void *addr, size_t size) >>>> } >>>> #endif >>>> >>>> +unsigned long arch_namespace_map_size(void); >>> >>> This property is more generic than the nvdimm namespace mapping size, >>> it's more the fundamental remap granularity that the architecture >>> supports. So I would expect this to be defined in core header files. >>> Something like: >>> >>> diff --git a/include/linux/io.h b/include/linux/io.h >>> index a59834bc0a11..58b3b2091dbb 100644 >>> --- a/include/linux/io.h >>> +++ b/include/linux/io.h >>> @@ -155,6 +155,13 @@ enum { >>> void *memremap(resource_size_t offset, size_t size, unsigned long flags); >>> void memunmap(void *addr); >>> >>> +#ifndef memremap_min_align >>> +static inline unsigned int memremap_min_align(void) >>> +{ >>> + return PAGE_SIZE; >>> +} >>> +#endif >>> + >> >> >> Should that be memremap_pages_min_align()? > > No, and on second look it needs to be a common value that results in > properly aligned / sized namespaces across architectures. > > What would it take for Power to make it's minimum mapping granularity > SUBSECTION_SIZE? The minute that the minimum alignment changes across > architectures we lose compatibility. > > The namespaces need to be sized such that the mode can be changed freely. > Linux on ppc64 with hash translation use just one page size for direct mapping and that is 16MB. -aneesh