From patchwork Wed Jan 15 08:27:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaud POULIQUEN X-Patchwork-Id: 11333511 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 685DE109A for ; Wed, 15 Jan 2020 08:29:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46C3D2467D for ; Wed, 15 Jan 2020 08:29:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=st.com header.i=@st.com header.b="XmTMhAP5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729238AbgAOI3L (ORCPT ); Wed, 15 Jan 2020 03:29:11 -0500 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:1040 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729188AbgAOI3G (ORCPT ); Wed, 15 Jan 2020 03:29:06 -0500 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00F8Rn5V008078; Wed, 15 Jan 2020 09:29:00 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=st.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=STMicroelectronics; bh=x+t2q3oFR0/g2C2BlDWSZ5LQ8cOF3XZQewhkJ5cwYOM=; b=XmTMhAP5BALer3IXtna0VSBMeosJlsVZHeDd4umTM1DaQgbw75ixQe/EJPR43iAVacNe ZTob3sj8auKOmZfRu2ChsRnMvIYJt6Sr3cj/kuJdJoJyLa2qI4d4Bw6r4Aq/sL3nywu+ s6NQp8yIVOqIGM9fv4vkBj+4mnhdInbd+hqRH0iIeSHyGWgWk7sOgfuXL3CNZBHxurCZ z1FLNk5MjzAA/o4gQjl0T4fm8RtEIVawoREl/XH5NR0GbP8BF54vI8cnYUkEUdpEyjM0 6XJkAk4eUkIWY/tBSsPT0z/Z+7KxrpNMhWRq4vRBivQgLx6JQu85QQekW719/X1PUXPI YQ== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 2xf78sa27p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 15 Jan 2020 09:29:00 +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 3FF4110002A; Wed, 15 Jan 2020 09:29:00 +0100 (CET) Received: from Webmail-eu.st.com (sfhdag3node1.st.com [10.75.127.7]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 2D13A210777; Wed, 15 Jan 2020 09:29:00 +0100 (CET) Received: from localhost (10.75.127.44) by SFHDAG3NODE1.st.com (10.75.127.7) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Wed, 15 Jan 2020 09:28:59 +0100 From: Arnaud Pouliquen To: Ohad Ben-Cohen , Bjorn Andersson , , , CC: , Suman Anna , Fabien DESSENNE , Subject: [PATCH v3] rpmsg: core: add API to get MTU Date: Wed, 15 Jan 2020 09:27:22 +0100 Message-ID: <20200115082722.13102-1-arnaud.pouliquen@st.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.75.127.44] X-ClientProxiedBy: SFHDAG1NODE3.st.com (10.75.127.3) To SFHDAG3NODE1.st.com (10.75.127.7) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-01-14_06:2020-01-14,2020-01-14 signatures=0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Return the rpmsg buffer MTU for sending message, so rpmsg users can split a long message in several sub rpmsg buffers. Signed-off-by: Arnaud Pouliquen Acked-by: Suman Anna --- V2[1] to V3 - fix parameter description in rpmsg_device_ops struct [1]: https://lore.kernel.org/patchwork/patch/1124684/ --- drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ drivers/rpmsg/rpmsg_internal.h | 2 ++ drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ include/linux/rpmsg.h | 10 ++++++++++ 4 files changed, 43 insertions(+) diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index e330ec4dfc33..a6ef54c4779a 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, } EXPORT_SYMBOL(rpmsg_trysend_offchannel); +/** + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. + * @ept: the rpmsg endpoint + * + * This function returns maximum buffer size available for a single message. + * + * Return: the maximum transmission size on success and an appropriate error + * value on failure. + */ + +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + if (WARN_ON(!ept)) + return -EINVAL; + if (!ept->ops->get_mtu) + return -ENOTSUPP; + + return ept->ops->get_mtu(ept); +} +EXPORT_SYMBOL(rpmsg_get_mtu); + /* * match an rpmsg channel with a channel info struct. * this is used to make sure we're not creating rpmsg devices for channels diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index 3fc83cd50e98..e6f88ee90ff6 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -47,6 +47,7 @@ struct rpmsg_device_ops { * @trysendto: see @rpmsg_trysendto(), optional * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional * @poll: see @rpmsg_poll(), optional + * @get_mtu: see @rpmsg_get_mtu(), optional * * Indirection table for the operations that a rpmsg backend should implement. * In addition to @destroy_ept, the backend must at least implement @send and @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops { void *data, int len); __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, poll_table *wait); + ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); }; int rpmsg_register_device(struct rpmsg_device *rpdev); diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index 376ebbf880d6..6e48fdf24555 100644 --- a/drivers/rpmsg/virtio_rpmsg_bus.c +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, void *data, int len); +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept); static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { .destroy_ept = virtio_rpmsg_destroy_ept, @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { .trysend = virtio_rpmsg_trysend, .trysendto = virtio_rpmsg_trysendto, .trysend_offchannel = virtio_rpmsg_trysend_offchannel, + .get_mtu = virtio_rpmsg_get_mtu, }; /** @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); } +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + struct rpmsg_device *rpdev = ept->rpdev; + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); + + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); +} + static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, struct rpmsg_hdr *msg, unsigned int len) { diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 9fe156d1c018..88d7892ca93d 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, poll_table *wait); +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); + #else static inline int register_rpmsg_device(struct rpmsg_device *dev) @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, return 0; } +static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return -ENXIO; +} + #endif /* IS_ENABLED(CONFIG_RPMSG) */ /* use a macro to avoid include chaining to get THIS_MODULE */