From patchwork Tue Jun 4 13:15:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 10975059 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 50E782D49 for ; Tue, 4 Jun 2019 13:18:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 416D620500 for ; Tue, 4 Jun 2019 13:18:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 34FCD26E54; Tue, 4 Jun 2019 13:18:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D3BEE22A6F for ; Tue, 4 Jun 2019 13:18:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727413AbfFDNSf (ORCPT ); Tue, 4 Jun 2019 09:18:35 -0400 Received: from lelv0142.ext.ti.com ([198.47.23.249]:39336 "EHLO lelv0142.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727182AbfFDNSf (ORCPT ); Tue, 4 Jun 2019 09:18:35 -0400 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id x54DIKwr120006; Tue, 4 Jun 2019 08:18:20 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1559654300; bh=oIzF4wPqwNRg9UTf2H8Siu9HoiPwFp65VY06zJhiVqk=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=wna+KbYt+4VB/bLdy1bkRaCyULLvGVx/mI+oJUkghKX4lGJWopq+C4sXX9eMeiSpx O5qN4L99Jrr4vwmjyI4vpeX2RsUM7jj7GTW7lxK0KgEuwSBzV+lB1qycprJVS2u0O0 +m8ljAtaLaKCE72BeDwTxsNujVHrS3BOUK1eWMjQ= Received: from DLEE105.ent.ti.com (dlee105.ent.ti.com [157.170.170.35]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x54DIKlP053724 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 4 Jun 2019 08:18:20 -0500 Received: from DLEE102.ent.ti.com (157.170.170.32) by DLEE105.ent.ti.com (157.170.170.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Tue, 4 Jun 2019 08:18:19 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DLEE102.ent.ti.com (157.170.170.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Tue, 4 Jun 2019 08:18:19 -0500 Received: from a0393678ub.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id x54DGdGX098972; Tue, 4 Jun 2019 08:18:14 -0500 From: Kishon Vijay Abraham I To: Tom Joseph , Bjorn Helgaas , Rob Herring , Mark Rutland , Lorenzo Pieralisi , Arnd Bergmann , Gustavo Pimentel CC: Greg Kroah-Hartman , Frank Rowand , Jingoo Han , , , , , , , Kishon Vijay Abraham I Subject: [RFC PATCH 17/30] PCI: endpoint: Protect concurrent access to pci_epf_ops with mutex Date: Tue, 4 Jun 2019 18:45:03 +0530 Message-ID: <20190604131516.13596-18-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190604131516.13596-1-kishon@ti.com> References: <20190604131516.13596-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Protect concurrent access to pci_epf_ops with mutex. Signed-off-by: Kishon Vijay Abraham I --- drivers/pci/endpoint/pci-epf-core.c | 11 ++++++++++- include/linux/pci-epf.h | 3 +++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c index 93f28c65ace0..6e0648991b5c 100644 --- a/drivers/pci/endpoint/pci-epf-core.c +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -35,7 +35,9 @@ void pci_epf_unbind(struct pci_epf *epf) return; } + mutex_lock(&epf->lock); epf->driver->ops->unbind(epf); + mutex_unlock(&epf->lock); module_put(epf->driver->owner); } EXPORT_SYMBOL_GPL(pci_epf_unbind); @@ -49,6 +51,8 @@ EXPORT_SYMBOL_GPL(pci_epf_unbind); */ int pci_epf_bind(struct pci_epf *epf) { + int ret; + if (!epf->driver) { dev_WARN(&epf->dev, "epf device not bound to driver\n"); return -EINVAL; @@ -57,7 +61,11 @@ int pci_epf_bind(struct pci_epf *epf) if (!try_module_get(epf->driver->owner)) return -EAGAIN; - return epf->driver->ops->bind(epf); + mutex_lock(&epf->lock); + ret = epf->driver->ops->bind(epf); + mutex_unlock(&epf->lock); + + return ret; } EXPORT_SYMBOL_GPL(pci_epf_bind); @@ -252,6 +260,7 @@ struct pci_epf *pci_epf_create(const char *name) device_initialize(dev); dev->bus = &pci_epf_bus_type; dev->type = &pci_epf_type; + mutex_init(&epf->lock); ret = dev_set_name(dev, "%s", name); if (ret) { diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 4993f7f6439b..bcdf4f07bde7 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -110,6 +110,7 @@ struct pci_epf_bar { * @driver: the EPF driver to which this EPF device is bound * @list: to add pci_epf as a list of PCI endpoint functions to pci_epc * @nb: notifier block to notify EPF of any EPC events (like linkup) + * @lock: mutex to protect pci_epf_ops */ struct pci_epf { struct device dev; @@ -124,6 +125,8 @@ struct pci_epf { struct pci_epf_driver *driver; struct list_head list; struct notifier_block nb; + /* mutex to protect against concurrent access of pci_epf_ops */ + struct mutex lock; }; #define to_pci_epf(epf_dev) container_of((epf_dev), struct pci_epf, dev)