From patchwork Fri Feb 21 03:27:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alastair D'Silva X-Patchwork-Id: 11395425 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 394A5159A for ; Fri, 21 Feb 2020 03:29:39 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (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 2198F20716 for ; Fri, 21 Feb 2020 03:29:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2198F20716 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=au1.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 08CCC10FC3638; Thu, 20 Feb 2020 19:30:31 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=alastair@au1.ibm.com; receiver= Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id C27C210FC360D for ; Thu, 20 Feb 2020 19:30:28 -0800 (PST) Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01L3L09u107976 for ; Thu, 20 Feb 2020 22:29:36 -0500 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ya6e618hd-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 20 Feb 2020 22:29:36 -0500 Received: from localhost by e06smtp03.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, 21 Feb 2020 03:29:27 -0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01L3SBe549086650 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 21 Feb 2020 03:28:11 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1757FA404D; Fri, 21 Feb 2020 03:28:11 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7252BA4040; Fri, 21 Feb 2020 03:28:10 +0000 (GMT) Received: from ozlabs.au.ibm.com (unknown [9.192.253.14]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 21 Feb 2020 03:28:10 +0000 (GMT) Received: from adsilva.ozlabs.ibm.com (haven.au.ibm.com [9.192.254.114]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id 7B369A03DD; Fri, 21 Feb 2020 14:28:03 +1100 (AEDT) From: "Alastair D'Silva" To: alastair@d-silva.org Subject: [PATCH v3 16/27] powerpc/powernv/pmem: Register a character device for userspace to interact with Date: Fri, 21 Feb 2020 14:27:09 +1100 X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200221032720.33893-1-alastair@au1.ibm.com> References: <20200221032720.33893-1-alastair@au1.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 x-cbid: 20022103-0012-0000-0000-00000388D1D4 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20022103-0013-0000-0000-000021C56A75 Message-Id: <20200221032720.33893-17-alastair@au1.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-20_19:2020-02-19,2020-02-20 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 suspectscore=3 phishscore=0 adultscore=0 clxscore=1015 impostorscore=0 malwarescore=0 spamscore=0 bulkscore=0 priorityscore=1501 mlxscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002210020 Message-ID-Hash: V5ZIQZC5T33LSOUBM474NTMMRAGETHEX X-Message-ID-Hash: V5ZIQZC5T33LSOUBM474NTMMRAGETHEX X-MailFrom: alastair@au1.ibm.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: "Aneesh Kumar K . V" , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Frederic Barrat , Andrew Donnellan , Arnd Bergmann , Greg Kroah-Hartman , 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_Go?= =?utf-8?q?ater?= , 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 X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: From: Alastair D'Silva This patch introduces a character device (/dev/ocxl-scmX) which further patches will use to interact with userspace. Signed-off-by: Alastair D'Silva --- arch/powerpc/platforms/powernv/pmem/ocxl.c | 116 +++++++++++++++++- .../platforms/powernv/pmem/ocxl_internal.h | 2 + 2 files changed, 116 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/powernv/pmem/ocxl.c b/arch/powerpc/platforms/powernv/pmem/ocxl.c index b8bd7e703b19..63109a870d2c 100644 --- a/arch/powerpc/platforms/powernv/pmem/ocxl.c +++ b/arch/powerpc/platforms/powernv/pmem/ocxl.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include "ocxl_internal.h" @@ -339,6 +340,9 @@ static void free_ocxlpmem(struct ocxlpmem *ocxlpmem) free_minor(ocxlpmem); + if (ocxlpmem->cdev.owner) + cdev_del(&ocxlpmem->cdev); + if (ocxlpmem->metadata_addr) devm_memunmap(&ocxlpmem->dev, ocxlpmem->metadata_addr); @@ -396,6 +400,70 @@ static int ocxlpmem_register(struct ocxlpmem *ocxlpmem) return device_register(&ocxlpmem->dev); } +static void ocxlpmem_put(struct ocxlpmem *ocxlpmem) +{ + put_device(&ocxlpmem->dev); +} + +static struct ocxlpmem *ocxlpmem_get(struct ocxlpmem *ocxlpmem) +{ + return (get_device(&ocxlpmem->dev) == NULL) ? NULL : ocxlpmem; +} + +static struct ocxlpmem *find_and_get_ocxlpmem(dev_t devno) +{ + struct ocxlpmem *ocxlpmem; + int minor = MINOR(devno); + /* + * We don't declare an RCU critical section here, as our AFU + * is protected by a reference counter on the device. By the time the + * minor number of a device is removed from the idr, the ref count of + * the device is already at 0, so no user API will access that AFU and + * this function can't return it. + */ + ocxlpmem = idr_find(&minors_idr, minor); + if (ocxlpmem) + ocxlpmem_get(ocxlpmem); + return ocxlpmem; +} + +static int file_open(struct inode *inode, struct file *file) +{ + struct ocxlpmem *ocxlpmem; + + ocxlpmem = find_and_get_ocxlpmem(inode->i_rdev); + if (!ocxlpmem) + return -ENODEV; + + file->private_data = ocxlpmem; + return 0; +} + +static int file_release(struct inode *inode, struct file *file) +{ + struct ocxlpmem *ocxlpmem = file->private_data; + + ocxlpmem_put(ocxlpmem); + return 0; +} + +static const struct file_operations fops = { + .owner = THIS_MODULE, + .open = file_open, + .release = file_release, +}; + +/** + * create_cdev() - Create the chardev in /dev for the device + * @ocxlpmem: the SCM metadata + * Return: 0 on success, negative on failure + */ +static int create_cdev(struct ocxlpmem *ocxlpmem) +{ + cdev_init(&ocxlpmem->cdev, &fops); + return cdev_add(&ocxlpmem->cdev, ocxlpmem->dev.devt, 1); +} + /** * ocxlpmem_remove() - Free an OpenCAPI persistent memory device * @pdev: the PCI device information struct @@ -572,6 +640,11 @@ static int probe(struct pci_dev *pdev, const struct pci_device_id *ent) goto err; } + if (create_cdev(ocxlpmem)) { + dev_err(&pdev->dev, "Could not create character device\n"); + goto err; + } + elapsed = 0; timeout = ocxlpmem->readiness_timeout + ocxlpmem->memory_available_timeout; while (!is_usable(ocxlpmem, false)) { @@ -613,20 +686,59 @@ static struct pci_driver pci_driver = { .shutdown = ocxlpmem_remove, }; +static int file_init(void) +{ + int rc; + + mutex_init(&minors_idr_lock); + idr_init(&minors_idr); + + rc = alloc_chrdev_region(&ocxlpmem_dev, 0, NUM_MINORS, "ocxl-pmem"); + if (rc) { + idr_destroy(&minors_idr); + pr_err("Unable to allocate OpenCAPI persistent memory major number: %d\n", rc); + return rc; + } + + ocxlpmem_class = class_create(THIS_MODULE, "ocxl-pmem"); + if (IS_ERR(ocxlpmem_class)) { + idr_destroy(&minors_idr); + pr_err("Unable to create ocxl-pmem class\n"); + unregister_chrdev_region(ocxlpmem_dev, NUM_MINORS); + return PTR_ERR(ocxlpmem_class); + } + + return 0; +} + +static void file_exit(void) +{ + class_destroy(ocxlpmem_class); + unregister_chrdev_region(ocxlpmem_dev, NUM_MINORS); + idr_destroy(&minors_idr); +} + static int __init ocxlpmem_init(void) { - int rc = 0; + int rc; - rc = pci_register_driver(&pci_driver); + rc = file_init(); if (rc) return rc; + rc = pci_register_driver(&pci_driver); + if (rc) { + file_exit(); + return rc; + } + return 0; } static void ocxlpmem_exit(void) { pci_unregister_driver(&pci_driver); + file_exit(); } module_init(ocxlpmem_init); diff --git a/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h b/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h index 28e2020f6355..d2d81fec7bb1 100644 --- a/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h +++ b/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h @@ -2,6 +2,7 @@ // Copyright 2019 IBM Corp. #include +#include #include #include #include @@ -99,6 +100,7 @@ struct ocxlpmem_function0 { struct ocxlpmem { struct device dev; struct pci_dev *pdev; + struct cdev cdev; struct ocxl_fn *ocxl_fn; struct nd_interleave_set nd_set; struct nvdimm_bus_descriptor bus_desc;