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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 80D9BC35679 for ; Mon, 24 Feb 2020 05:25:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 624F620661 for ; Mon, 24 Feb 2020 05:25:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726810AbgBXFZf (ORCPT ); Mon, 24 Feb 2020 00:25:35 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:23354 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725809AbgBXFZe (ORCPT ); Mon, 24 Feb 2020 00:25:34 -0500 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01O5NIQH038226 for ; Mon, 24 Feb 2020 00:25:33 -0500 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2yb1b6t784-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 24 Feb 2020 00:25:33 -0500 Received: from localhost by e06smtp07.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) Mon, 24 Feb 2020 05:25:22 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01O5PMZK59179238 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 24 Feb 2020 05:25:22 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F40E84C044; Mon, 24 Feb 2020 05:25:21 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 534144C04A; Mon, 24 Feb 2020 05:25:21 +0000 (GMT) Received: from ozlabs.au.ibm.com (unknown [9.192.253.14]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 24 Feb 2020 05:25:21 +0000 (GMT) Received: from [10.61.2.125] (haven.au.ibm.com [9.192.254.114]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id 89CE7A00E5; Mon, 24 Feb 2020 16:25:15 +1100 (AEDT) Subject: Re: [PATCH v3 06/27] ocxl: Tally up the LPC memory on a link & allow it to be mapped To: "Alastair D'Silva" , alastair@d-silva.org Cc: "Aneesh Kumar K . V" , "Oliver O'Halloran" , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Frederic Barrat , Arnd Bergmann , Greg Kroah-Hartman , Dan Williams , Vishal Verma , Dave Jiang , Ira Weiny , Andrew Morton , Mauro Carvalho Chehab , "David S. Miller" , Rob Herring , Anton Blanchard , Krzysztof Kozlowski , Mahesh Salgaonkar , Madhavan Srinivasan , =?UTF-8?Q?C=c3=a9dric_Le_Goater?= , Anju T Sudhakar , Hari Bathini , Thomas Gleixner , Greg Kurz , Nicholas Piggin , Masahiro Yamada , Alexey Kardashevskiy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-nvdimm@lists.01.org, linux-mm@kvack.org References: <20200221032720.33893-1-alastair@au1.ibm.com> <20200221032720.33893-7-alastair@au1.ibm.com> From: Andrew Donnellan Date: Mon, 24 Feb 2020 16:25:18 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200221032720.33893-7-alastair@au1.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 20022405-0028-0000-0000-000003DD5D6E X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20022405-0029-0000-0000-000024A27116 Message-Id: <8a6eaedd-d806-9111-84ac-c4961227d69c@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-24_01:2020-02-21,2020-02-24 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 mlxscore=0 malwarescore=0 phishscore=0 mlxlogscore=999 lowpriorityscore=0 bulkscore=0 adultscore=0 impostorscore=0 clxscore=1015 priorityscore=1501 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002240044 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/2/20 2:26 pm, Alastair D'Silva wrote: > From: Alastair D'Silva > > Tally up the LPC memory on an OpenCAPI link & allow it to be mapped > > Signed-off-by: Alastair D'Silva This commit message is a bit short and could do with some further explanation. In particular - it's worth explaining why the tracking of available LPC memory needs to be done at a link level, because a single OpenCAPI card can have multiple PCI functions, each with multiple AFUs which define an amount of LPC memory they have, even if the common case is expected to be a single function with a single AFU and thus one LPC area per link. Snowpatch has a few checkpatch issues to report: https://openpower.xyz/job/snowpatch/job/snowpatch-linux-checkpatch/11800//artifact/linux/checkpatch.log The code generally looks okay to me. > diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h > index 198e4e4bc51d..d0c8c4838f42 100644 > --- a/drivers/misc/ocxl/ocxl_internal.h > +++ b/drivers/misc/ocxl/ocxl_internal.h > @@ -142,4 +142,37 @@ int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset); > u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id); > void ocxl_afu_irq_free_all(struct ocxl_context *ctx); > > +/** > + * ocxl_link_add_lpc_mem() - Increment the amount of memory required by an OpenCAPI link > + * > + * @link_handle: The OpenCAPI link handle > + * @offset: The offset of the memory to add > + * @size: The amount of memory to increment by > + * > + * Returns 0 on success, negative on overflow > + */ I think "amount of memory required" isn't the best way to express this. Might as well explicitly say -EINVAL on overflow. -- Andrew Donnellan OzLabs, ADL Canberra ajd@linux.ibm.com IBM Australia Limited