From patchwork Thu Jul 1 09:04:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaud Pouliquen X-Patchwork-Id: 12353735 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 C3103C11F6B for ; Thu, 1 Jul 2021 09:04:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B27F46146B for ; Thu, 1 Jul 2021 09:04:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235715AbhGAJHD (ORCPT ); Thu, 1 Jul 2021 05:07:03 -0400 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:31034 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S235673AbhGAJHB (ORCPT ); Thu, 1 Jul 2021 05:07:01 -0400 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 16192qFR005255; Thu, 1 Jul 2021 11:04:25 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=selector1; bh=1Yj6EtZ1g7tfYQMs8m+xbY0fitcrvF3Yqp2y2fJy8xo=; b=lN8fgJcmwhTeLxTzqs8tdafQlI0nobJSnNREp4EHha8kGzmZRdTju703VQVggIJ/tFa6 6XFHw81DMkapNshpRECT9mxeXecBtCf6hnZLK0CyfL1eokqnG9eU2eEwR+r9Wjq66vvS eaw7msZlFvh1ad0pQc/PHUMPdzKCROwAlcQJd0Z1OnQCIsDXTX7IIPFwV4kQnWvQdPmi uTt3f8mj+sOZwjSlH/EjiGfOxSbBqXiJCiOgzvSpKsM7P9gpBx2jfr4ooJwEruTDyt0B cenp5BkOyBQxJD2/HHZyEfaUeSsFgNQitiOXN0wVdE9cAyNtjrCpk9grEcxZn4m9tYld Nw== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 39h7yj2bk1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 01 Jul 2021 11:04:25 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id BFA25100034; Thu, 1 Jul 2021 11:04:24 +0200 (CEST) Received: from Webmail-eu.st.com (sfhdag2node3.st.com [10.75.127.6]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id B213A2138C8; Thu, 1 Jul 2021 11:04:24 +0200 (CEST) Received: from localhost (10.75.127.45) by SFHDAG2NODE3.st.com (10.75.127.6) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 1 Jul 2021 11:04:24 +0200 From: Arnaud Pouliquen To: Bjorn Andersson , Ohad Ben-Cohen , Mathieu Poirier CC: , , , , Subject: [PATCH v3 3/4] rpmsg: char: Add possibility to use default endpoint of the rpmsg device. Date: Thu, 1 Jul 2021 11:04:12 +0200 Message-ID: <20210701090413.3104-4-arnaud.pouliquen@foss.st.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210701090413.3104-1-arnaud.pouliquen@foss.st.com> References: <20210701090413.3104-1-arnaud.pouliquen@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.45] X-ClientProxiedBy: SFHDAG1NODE3.st.com (10.75.127.3) To SFHDAG2NODE3.st.com (10.75.127.6) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.790 definitions=2021-07-01_06:2021-06-30,2021-07-01 signatures=0 Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org Current implementation create/destroy a new endpoint on each rpmsg_eptdev_open/rpmsg_eptdev_release calls. For a rpmsg device created by the NS announcement mechanism we need to use a unique static endpoint that is the default rpmsg device endpoint associated to the channel. This patch prepares the introduction of a rpmsg channel device for the char device. The rpmsg channel device will require a default endpoint to communicate to the remote processor. Add the static_ept field in rpmsg_eptdev structure. This boolean determines the behavior on rpmsg_eptdev_open and rpmsg_eptdev_release call. - If static_ept == false: Use the legacy behavior by creating a new endpoint each time rpmsg_eptdev_open is called and release it when rpmsg_eptdev_release is called on /dev/rpmsgX device open/close. - If static_ept == true: use the rpmsg device default endpoint for the communication. - Address the update of _rpmsg_chrdev_eptdev_create in e separate patch for readability. Add protection in rpmsg_eptdev_ioctl to prevent to destroy a default endpoint. Signed-off-by: Arnaud Pouliquen Reviewed-by: Mathieu Poirier --- update vs V2: - remove null pointer check for eptdev->rpdev in rpmsg_eptdev_ioctl. The pointer is set in __rpmsg_chrdev_eptdev_create and cannot be null. --- drivers/rpmsg/rpmsg_char.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c index 50b7d4b00175..bd728d90ba4c 100644 --- a/drivers/rpmsg/rpmsg_char.c +++ b/drivers/rpmsg/rpmsg_char.c @@ -45,6 +45,8 @@ static DEFINE_IDA(rpmsg_minor_ida); * @queue_lock: synchronization of @queue operations * @queue: incoming message queue * @readq: wait object for incoming queue + * @static_ept: specify if the endpoint has to be created at each device opening or + * if the default endpoint should be used. */ struct rpmsg_eptdev { struct device dev; @@ -59,6 +61,8 @@ struct rpmsg_eptdev { spinlock_t queue_lock; struct sk_buff_head queue; wait_queue_head_t readq; + + bool static_ept; }; int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) @@ -116,7 +120,15 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) get_device(dev); - ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo); + /* + * If the static_ept is set to true, the rpmsg device default endpoint is used. + * Else a new endpoint is created on open that will be destroyed on release. + */ + if (eptdev->static_ept) + ept = rpdev->ept; + else + ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo); + if (!ept) { dev_err(dev, "failed to open %s\n", eptdev->chinfo.name); put_device(dev); @@ -137,7 +149,8 @@ static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) /* Close the endpoint, if it's not already destroyed by the parent */ mutex_lock(&eptdev->ept_lock); if (eptdev->ept) { - rpmsg_destroy_ept(eptdev->ept); + if (!eptdev->static_ept) + rpmsg_destroy_ept(eptdev->ept); eptdev->ept = NULL; } mutex_unlock(&eptdev->ept_lock); @@ -264,6 +277,10 @@ static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, if (cmd != RPMSG_DESTROY_EPT_IOCTL) return -EINVAL; + /* Don't allow to destroy a default endpoint. */ + if (eptdev->ept == eptdev->rpdev->ept) + return -EPERM; + return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL); }