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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 84FD2C31E44 for ; Mon, 17 Jun 2019 05:17:01 +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 BA978218A0 for ; Mon, 17 Jun 2019 05:17:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BA978218A0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=au1.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 45RzwT6X4BzDqcH for ; Mon, 17 Jun 2019 15:16:57 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=au1.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=alastair@au1.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=au1.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 45RztZ2BglzDqVP for ; Mon, 17 Jun 2019 15:15:17 +1000 (AEST) Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x5H4c23V087993 for ; Mon, 17 Jun 2019 00:42:20 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2t62a8jxu1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 17 Jun 2019 00:42:20 -0400 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) Mon, 17 Jun 2019 05:42:16 +0100 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x5H4g7tp27001144 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 17 Jun 2019 04:42:07 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5821342042; Mon, 17 Jun 2019 04:42:15 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0857F42041; Mon, 17 Jun 2019 04:42:15 +0000 (GMT) Received: from ozlabs.au.ibm.com (unknown [9.192.253.14]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 17 Jun 2019 04:42:14 +0000 (GMT) Received: from adsilva.ozlabs.ibm.com (haven.au.ibm.com [9.192.254.114]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id DE718A0208; Mon, 17 Jun 2019 14:42:13 +1000 (AEST) From: "Alastair D'Silva" To: alastair@d-silva.org Subject: [PATCH] ocxl: Allow contexts to be attached with a NULL mm Date: Mon, 17 Jun 2019 14:41:52 +1000 X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19061704-0020-0000-0000-0000034AAC54 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19061704-0021-0000-0000-0000219DEF49 Message-Id: <20190617044152.13707-1-alastair@au1.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-06-17_03:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=644 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906170042 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: Andrew Donnellan , Arnd Bergmann , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Frederic Barrat , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Alastair D'Silva If an OpenCAPI context is to be used directly by a kernel driver, there may not be a suitable mm to use. The patch makes the mm parameter to ocxl_context_attach optional. Signed-off-by: Alastair D'Silva --- drivers/misc/ocxl/context.c | 9 ++++++--- drivers/misc/ocxl/link.c | 12 ++++++++---- 2 files changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/misc/ocxl/context.c b/drivers/misc/ocxl/context.c index bab9c9364184..994563a078eb 100644 --- a/drivers/misc/ocxl/context.c +++ b/drivers/misc/ocxl/context.c @@ -69,6 +69,7 @@ static void xsl_fault_error(void *data, u64 addr, u64 dsisr) int ocxl_context_attach(struct ocxl_context *ctx, u64 amr, struct mm_struct *mm) { int rc; + unsigned long pidr = 0; // Locks both status & tidr mutex_lock(&ctx->status_mutex); @@ -77,9 +78,11 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr, struct mm_struct *mm) goto out; } - rc = ocxl_link_add_pe(ctx->afu->fn->link, ctx->pasid, - mm->context.id, ctx->tidr, amr, mm, - xsl_fault_error, ctx); + if (mm) + pidr = mm->context.id; + + rc = ocxl_link_add_pe(ctx->afu->fn->link, ctx->pasid, pidr, ctx->tidr, + amr, mm, xsl_fault_error, ctx); if (rc) goto out; diff --git a/drivers/misc/ocxl/link.c b/drivers/misc/ocxl/link.c index cce5b0d64505..43542f124807 100644 --- a/drivers/misc/ocxl/link.c +++ b/drivers/misc/ocxl/link.c @@ -523,7 +523,8 @@ int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr, pe->amr = cpu_to_be64(amr); pe->software_state = cpu_to_be32(SPA_PE_VALID); - mm_context_add_copro(mm); + if (mm) + mm_context_add_copro(mm); /* * Barrier is to make sure PE is visible in the SPA before it * is used by the device. It also helps with the global TLBI @@ -546,7 +547,8 @@ int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr, * have a reference on mm_users. Incrementing mm_count solves * the problem. */ - mmgrab(mm); + if (mm) + mmgrab(mm); trace_ocxl_context_add(current->pid, spa->spa_mem, pasid, pidr, tidr); unlock: mutex_unlock(&spa->spa_lock); @@ -652,8 +654,10 @@ int ocxl_link_remove_pe(void *link_handle, int pasid) if (!pe_data) { WARN(1, "Couldn't find pe data when removing PE\n"); } else { - mm_context_remove_copro(pe_data->mm); - mmdrop(pe_data->mm); + if (pe_data->mm) { + mm_context_remove_copro(pe_data->mm); + mmdrop(pe_data->mm); + } kfree_rcu(pe_data, rcu); } unlock: -- 2.21.0