From patchwork Tue Dec 7 08:08:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaud POULIQUEN X-Patchwork-Id: 12661287 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9023C433F5 for ; Tue, 7 Dec 2021 08:10:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232178AbhLGINp (ORCPT ); Tue, 7 Dec 2021 03:13:45 -0500 Received: from mx07-00178001.pphosted.com ([185.132.182.106]:58842 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232146AbhLGINl (ORCPT ); Tue, 7 Dec 2021 03:13:41 -0500 Received: from pps.filterd (m0288072.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 1B71FB2a003535; Tue, 7 Dec 2021 09:10:02 +0100 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=mXiPNNbGuPxxED0nQioEMAy2JP59uV0ofbb8aTjGD5k=; b=Lhnod9sLgmxgRJUMQ56D5M1OyHFZXrqm/YzePZAYD061llKCd6d8OMksndSwHUctyp3M ZC0yQBNn56nFJiVIPvg2F6wi32UiEx4xxft5CcaBVafbTiivG+3jpaj9ZTJLa3AxtBaG qFZ1QpHBrCIgTAomBd6UStSzWIvgC6nHMVmNl8S8eALBbUzOPjZBTdzX+NJ3H7Fuomrm v4t5k9s/LvWpKoajFQ6TaqkwJ+0/Ms00WEpES7cmjCSw40zrFXfOyJNzMiWXvUC2YMaT Zq+fhXatQPew0rHOTFaE/owtSAZQseuNnHoz7h8Zo+hcZyxm7jEgAwT9xtxIue9vUA6X 0w== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3csmx0kp5j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 07 Dec 2021 09:10:02 +0100 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 973E8100034; Tue, 7 Dec 2021 09:10:01 +0100 (CET) Received: from Webmail-eu.st.com (sfhdag2node2.st.com [10.75.127.5]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id E81E221B526; Tue, 7 Dec 2021 09:10:00 +0100 (CET) Received: from localhost (10.75.127.48) by SFHDAG2NODE2.st.com (10.75.127.5) with Microsoft SMTP Server (TLS) id 15.0.1497.26; Tue, 7 Dec 2021 09:10:00 +0100 From: Arnaud Pouliquen To: Bjorn Andersson , Mathieu Poirier CC: , , , , Subject: [PATCH v8 10/13] rpmsg: char: Add possibility to use default endpoint of the rpmsg device. Date: Tue, 7 Dec 2021 09:08:40 +0100 Message-ID: <20211207080843.21222-11-arnaud.pouliquen@foss.st.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211207080843.21222-1-arnaud.pouliquen@foss.st.com> References: <20211207080843.21222-1-arnaud.pouliquen@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.48] X-ClientProxiedBy: SFHDAG1NODE2.st.com (10.75.127.2) To SFHDAG2NODE2.st.com (10.75.127.5) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2021-12-07_03,2021-12-06_02,2021-12-02_01 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 default_ept field in rpmsg_eptdev structure.This pointer determines the behavior on rpmsg_eptdev_open and rpmsg_eptdev_release call. - If default_ept == NULL: 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 default_ept is set: use the rpmsg device default endpoint for the communication. Address the update of _rpmsg_chrdev_eptdev_create in a separate patch for readability. Add protection in rpmsg_eptdev_ioctl to prevent to destroy a default endpoint. Signed-off-by: Arnaud Pouliquen --- Update vs previous revision: - fix comment in rpmsg_eptdev_open --- 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 a39f19161cd6..cf97839f5833 100644 --- a/drivers/rpmsg/rpmsg_char.c +++ b/drivers/rpmsg/rpmsg_char.c @@ -50,6 +50,8 @@ static DEFINE_IDA(rpmsg_minor_ida); * @queue_lock: synchronization of @queue operations * @queue: incoming message queue * @readq: wait object for incoming queue + * @default_ept: set to channel default endpoint if the default endpoint should be re-used + * on device open to prevent endpoint address update. */ struct rpmsg_eptdev { struct device dev; @@ -60,10 +62,12 @@ struct rpmsg_eptdev { struct mutex ept_lock; struct rpmsg_endpoint *ept; + struct rpmsg_endpoint *default_ept; spinlock_t queue_lock; struct sk_buff_head queue; wait_queue_head_t readq; + }; int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) @@ -121,7 +125,15 @@ 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 default_ept is set, the rpmsg device default endpoint is used. + * Else a new endpoint is created on open that will be destroyed on release. + */ + if (eptdev->default_ept) + ept = eptdev->default_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); @@ -142,7 +154,8 @@ 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->default_ept) + rpmsg_destroy_ept(eptdev->ept); eptdev->ept = NULL; } mutex_unlock(&eptdev->ept_lock); @@ -269,6 +282,10 @@ 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->default_ept) + return -EINVAL; + return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL); }