From patchwork Wed Jan 13 21:13:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 12018403 X-Patchwork-Delegate: kuba@kernel.org 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4BEADC433E0 for ; Thu, 14 Jan 2021 02:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0798923447 for ; Thu, 14 Jan 2021 02:17:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729043AbhANCRk (ORCPT ); Wed, 13 Jan 2021 21:17:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729018AbhAMVPG (ORCPT ); Wed, 13 Jan 2021 16:15:06 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C51B3C0617AB for ; Wed, 13 Jan 2021 13:14:26 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kznTF-0001gZ-9h for netdev@vger.kernel.org; Wed, 13 Jan 2021 22:14:25 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 0874D5C3045 for ; Wed, 13 Jan 2021 21:14:19 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id 84C275C3001; Wed, 13 Jan 2021 21:14:12 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id 3b08379b; Wed, 13 Jan 2021 21:14:11 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Marc Kleine-Budde , Vincent Mailhol Subject: [net-next 06/17] can: dev: move skb related into seperate file Date: Wed, 13 Jan 2021 22:13:59 +0100 Message-Id: <20210113211410.917108-7-mkl@pengutronix.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210113211410.917108-1-mkl@pengutronix.de> References: <20210113211410.917108-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This patch moves the skb related code of the CAN device infrastructure into a separate file. Reviewed-by: Vincent Mailhol Link: https://lore.kernel.org/r/20210111141930.693847-6-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde --- drivers/net/can/dev/Makefile | 1 + drivers/net/can/dev/dev.c | 213 --------------------------------- drivers/net/can/dev/skb.c | 220 +++++++++++++++++++++++++++++++++++ include/linux/can/dev.h | 76 ------------ include/linux/can/skb.h | 77 ++++++++++++ 5 files changed, 298 insertions(+), 289 deletions(-) create mode 100644 drivers/net/can/dev/skb.c diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile index 5c647951e06d..188bd53b113c 100644 --- a/drivers/net/can/dev/Makefile +++ b/drivers/net/can/dev/Makefile @@ -5,5 +5,6 @@ can-dev-y += bittiming.o can-dev-y += dev.o can-dev-y += length.o can-dev-y += rx-offload.o +can-dev-y += skb.o can-dev-$(CONFIG_CAN_LEDS) += led.o diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c index 3372e99d5db7..fe71ff9ef8c9 100644 --- a/drivers/net/can/dev/dev.c +++ b/drivers/net/can/dev/dev.c @@ -132,149 +132,6 @@ void can_change_state(struct net_device *dev, struct can_frame *cf, } EXPORT_SYMBOL_GPL(can_change_state); -/* Local echo of CAN messages - * - * CAN network devices *should* support a local echo functionality - * (see Documentation/networking/can.rst). To test the handling of CAN - * interfaces that do not support the local echo both driver types are - * implemented. In the case that the driver does not support the echo - * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core - * to perform the echo as a fallback solution. - */ -static void can_flush_echo_skb(struct net_device *dev) -{ - struct can_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - int i; - - for (i = 0; i < priv->echo_skb_max; i++) { - if (priv->echo_skb[i]) { - kfree_skb(priv->echo_skb[i]); - priv->echo_skb[i] = NULL; - stats->tx_dropped++; - stats->tx_aborted_errors++; - } - } -} - -/* Put the skb on the stack to be looped backed locally lateron - * - * The function is typically called in the start_xmit function - * of the device driver. The driver must protect access to - * priv->echo_skb, if necessary. - */ -int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, - unsigned int idx) -{ - struct can_priv *priv = netdev_priv(dev); - - BUG_ON(idx >= priv->echo_skb_max); - - /* check flag whether this packet has to be looped back */ - if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK || - (skb->protocol != htons(ETH_P_CAN) && - skb->protocol != htons(ETH_P_CANFD))) { - kfree_skb(skb); - return 0; - } - - if (!priv->echo_skb[idx]) { - skb = can_create_echo_skb(skb); - if (!skb) - return -ENOMEM; - - /* make settings for echo to reduce code in irq context */ - skb->pkt_type = PACKET_BROADCAST; - skb->ip_summed = CHECKSUM_UNNECESSARY; - skb->dev = dev; - - /* save this skb for tx interrupt echo handling */ - priv->echo_skb[idx] = skb; - } else { - /* locking problem with netif_stop_queue() ?? */ - netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx); - kfree_skb(skb); - return -EBUSY; - } - - return 0; -} -EXPORT_SYMBOL_GPL(can_put_echo_skb); - -struct sk_buff * -__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr) -{ - struct can_priv *priv = netdev_priv(dev); - - if (idx >= priv->echo_skb_max) { - netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", - __func__, idx, priv->echo_skb_max); - return NULL; - } - - if (priv->echo_skb[idx]) { - /* Using "struct canfd_frame::len" for the frame - * length is supported on both CAN and CANFD frames. - */ - struct sk_buff *skb = priv->echo_skb[idx]; - struct canfd_frame *cf = (struct canfd_frame *)skb->data; - - /* get the real payload length for netdev statistics */ - if (cf->can_id & CAN_RTR_FLAG) - *len_ptr = 0; - else - *len_ptr = cf->len; - - priv->echo_skb[idx] = NULL; - - return skb; - } - - return NULL; -} - -/* Get the skb from the stack and loop it back locally - * - * The function is typically called when the TX done interrupt - * is handled in the device driver. The driver must protect - * access to priv->echo_skb, if necessary. - */ -unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx) -{ - struct sk_buff *skb; - u8 len; - - skb = __can_get_echo_skb(dev, idx, &len); - if (!skb) - return 0; - - skb_get(skb); - if (netif_rx(skb) == NET_RX_SUCCESS) - dev_consume_skb_any(skb); - else - dev_kfree_skb_any(skb); - - return len; -} -EXPORT_SYMBOL_GPL(can_get_echo_skb); - -/* Remove the skb from the stack and free it. - * - * The function is typically called when TX failed. - */ -void can_free_echo_skb(struct net_device *dev, unsigned int idx) -{ - struct can_priv *priv = netdev_priv(dev); - - BUG_ON(idx >= priv->echo_skb_max); - - if (priv->echo_skb[idx]) { - dev_kfree_skb_any(priv->echo_skb[idx]); - priv->echo_skb[idx] = NULL; - } -} -EXPORT_SYMBOL_GPL(can_free_echo_skb); - /* CAN device restart for bus-off recovery */ static void can_restart(struct net_device *dev) { @@ -379,76 +236,6 @@ static void can_setup(struct net_device *dev) dev->features = NETIF_F_HW_CSUM; } -struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) -{ - struct sk_buff *skb; - - skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + - sizeof(struct can_frame)); - if (unlikely(!skb)) - return NULL; - - skb->protocol = htons(ETH_P_CAN); - skb->pkt_type = PACKET_BROADCAST; - skb->ip_summed = CHECKSUM_UNNECESSARY; - - skb_reset_mac_header(skb); - skb_reset_network_header(skb); - skb_reset_transport_header(skb); - - can_skb_reserve(skb); - can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; - - *cf = skb_put_zero(skb, sizeof(struct can_frame)); - - return skb; -} -EXPORT_SYMBOL_GPL(alloc_can_skb); - -struct sk_buff *alloc_canfd_skb(struct net_device *dev, - struct canfd_frame **cfd) -{ - struct sk_buff *skb; - - skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + - sizeof(struct canfd_frame)); - if (unlikely(!skb)) - return NULL; - - skb->protocol = htons(ETH_P_CANFD); - skb->pkt_type = PACKET_BROADCAST; - skb->ip_summed = CHECKSUM_UNNECESSARY; - - skb_reset_mac_header(skb); - skb_reset_network_header(skb); - skb_reset_transport_header(skb); - - can_skb_reserve(skb); - can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; - - *cfd = skb_put_zero(skb, sizeof(struct canfd_frame)); - - return skb; -} -EXPORT_SYMBOL_GPL(alloc_canfd_skb); - -struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) -{ - struct sk_buff *skb; - - skb = alloc_can_skb(dev, cf); - if (unlikely(!skb)) - return NULL; - - (*cf)->can_id = CAN_ERR_FLAG; - (*cf)->len = CAN_ERR_DLC; - - return skb; -} -EXPORT_SYMBOL_GPL(alloc_can_err_skb); - /* Allocate and setup space for the CAN network device */ struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, unsigned int txqs, unsigned int rxqs) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c new file mode 100644 index 000000000000..26cd597ff771 --- /dev/null +++ b/drivers/net/can/dev/skb.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix + * Copyright (C) 2006 Andrey Volkov, Varma Electronics + * Copyright (C) 2008-2009 Wolfgang Grandegger + */ + +#include + +/* Local echo of CAN messages + * + * CAN network devices *should* support a local echo functionality + * (see Documentation/networking/can.rst). To test the handling of CAN + * interfaces that do not support the local echo both driver types are + * implemented. In the case that the driver does not support the echo + * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core + * to perform the echo as a fallback solution. + */ +void can_flush_echo_skb(struct net_device *dev) +{ + struct can_priv *priv = netdev_priv(dev); + struct net_device_stats *stats = &dev->stats; + int i; + + for (i = 0; i < priv->echo_skb_max; i++) { + if (priv->echo_skb[i]) { + kfree_skb(priv->echo_skb[i]); + priv->echo_skb[i] = NULL; + stats->tx_dropped++; + stats->tx_aborted_errors++; + } + } +} + +/* Put the skb on the stack to be looped backed locally lateron + * + * The function is typically called in the start_xmit function + * of the device driver. The driver must protect access to + * priv->echo_skb, if necessary. + */ +int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, + unsigned int idx) +{ + struct can_priv *priv = netdev_priv(dev); + + BUG_ON(idx >= priv->echo_skb_max); + + /* check flag whether this packet has to be looped back */ + if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK || + (skb->protocol != htons(ETH_P_CAN) && + skb->protocol != htons(ETH_P_CANFD))) { + kfree_skb(skb); + return 0; + } + + if (!priv->echo_skb[idx]) { + skb = can_create_echo_skb(skb); + if (!skb) + return -ENOMEM; + + /* make settings for echo to reduce code in irq context */ + skb->pkt_type = PACKET_BROADCAST; + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->dev = dev; + + /* save this skb for tx interrupt echo handling */ + priv->echo_skb[idx] = skb; + } else { + /* locking problem with netif_stop_queue() ?? */ + netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx); + kfree_skb(skb); + return -EBUSY; + } + + return 0; +} +EXPORT_SYMBOL_GPL(can_put_echo_skb); + +struct sk_buff * +__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr) +{ + struct can_priv *priv = netdev_priv(dev); + + if (idx >= priv->echo_skb_max) { + netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", + __func__, idx, priv->echo_skb_max); + return NULL; + } + + if (priv->echo_skb[idx]) { + /* Using "struct canfd_frame::len" for the frame + * length is supported on both CAN and CANFD frames. + */ + struct sk_buff *skb = priv->echo_skb[idx]; + struct canfd_frame *cf = (struct canfd_frame *)skb->data; + + /* get the real payload length for netdev statistics */ + if (cf->can_id & CAN_RTR_FLAG) + *len_ptr = 0; + else + *len_ptr = cf->len; + + priv->echo_skb[idx] = NULL; + + return skb; + } + + return NULL; +} + +/* Get the skb from the stack and loop it back locally + * + * The function is typically called when the TX done interrupt + * is handled in the device driver. The driver must protect + * access to priv->echo_skb, if necessary. + */ +unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx) +{ + struct sk_buff *skb; + u8 len; + + skb = __can_get_echo_skb(dev, idx, &len); + if (!skb) + return 0; + + skb_get(skb); + if (netif_rx(skb) == NET_RX_SUCCESS) + dev_consume_skb_any(skb); + else + dev_kfree_skb_any(skb); + + return len; +} +EXPORT_SYMBOL_GPL(can_get_echo_skb); + +/* Remove the skb from the stack and free it. + * + * The function is typically called when TX failed. + */ +void can_free_echo_skb(struct net_device *dev, unsigned int idx) +{ + struct can_priv *priv = netdev_priv(dev); + + BUG_ON(idx >= priv->echo_skb_max); + + if (priv->echo_skb[idx]) { + dev_kfree_skb_any(priv->echo_skb[idx]); + priv->echo_skb[idx] = NULL; + } +} +EXPORT_SYMBOL_GPL(can_free_echo_skb); + +struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) +{ + struct sk_buff *skb; + + skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + + sizeof(struct can_frame)); + if (unlikely(!skb)) + return NULL; + + skb->protocol = htons(ETH_P_CAN); + skb->pkt_type = PACKET_BROADCAST; + skb->ip_summed = CHECKSUM_UNNECESSARY; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + *cf = skb_put_zero(skb, sizeof(struct can_frame)); + + return skb; +} +EXPORT_SYMBOL_GPL(alloc_can_skb); + +struct sk_buff *alloc_canfd_skb(struct net_device *dev, + struct canfd_frame **cfd) +{ + struct sk_buff *skb; + + skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + + sizeof(struct canfd_frame)); + if (unlikely(!skb)) + return NULL; + + skb->protocol = htons(ETH_P_CANFD); + skb->pkt_type = PACKET_BROADCAST; + skb->ip_summed = CHECKSUM_UNNECESSARY; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + *cfd = skb_put_zero(skb, sizeof(struct canfd_frame)); + + return skb; +} +EXPORT_SYMBOL_GPL(alloc_canfd_skb); + +struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) +{ + struct sk_buff *skb; + + skb = alloc_can_skb(dev, cf); + if (unlikely(!skb)) + return NULL; + + (*cf)->can_id = CAN_ERR_FLAG; + (*cf)->len = CAN_ERR_DLC; + + return skb; +} +EXPORT_SYMBOL_GPL(alloc_can_err_skb); diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index d75fba1d030a..4a26e128af7f 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -84,69 +84,6 @@ struct can_priv { #endif }; -/* Check for outgoing skbs that have not been created by the CAN subsystem */ -static inline bool can_skb_headroom_valid(struct net_device *dev, - struct sk_buff *skb) -{ - /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */ - if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv))) - return false; - - /* af_packet does not apply CAN skb specific settings */ - if (skb->ip_summed == CHECKSUM_NONE) { - /* init headroom */ - can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; - - skb->ip_summed = CHECKSUM_UNNECESSARY; - - /* perform proper loopback on capable devices */ - if (dev->flags & IFF_ECHO) - skb->pkt_type = PACKET_LOOPBACK; - else - skb->pkt_type = PACKET_HOST; - - skb_reset_mac_header(skb); - skb_reset_network_header(skb); - skb_reset_transport_header(skb); - } - - return true; -} - -/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ -static inline bool can_dropped_invalid_skb(struct net_device *dev, - struct sk_buff *skb) -{ - const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; - - if (skb->protocol == htons(ETH_P_CAN)) { - if (unlikely(skb->len != CAN_MTU || - cfd->len > CAN_MAX_DLEN)) - goto inval_skb; - } else if (skb->protocol == htons(ETH_P_CANFD)) { - if (unlikely(skb->len != CANFD_MTU || - cfd->len > CANFD_MAX_DLEN)) - goto inval_skb; - } else - goto inval_skb; - - if (!can_skb_headroom_valid(dev, skb)) - goto inval_skb; - - return false; - -inval_skb: - kfree_skb(skb); - dev->stats.tx_dropped++; - return true; -} - -static inline bool can_is_canfd_skb(const struct sk_buff *skb) -{ - /* the CAN specific type of skb is identified by its data length */ - return skb->len == CANFD_MTU; -} /* helper to define static CAN controller features at device creation time */ static inline void can_set_static_ctrlmode(struct net_device *dev, @@ -187,23 +124,10 @@ void can_bus_off(struct net_device *dev); void can_change_state(struct net_device *dev, struct can_frame *cf, enum can_state tx_state, enum can_state rx_state); -int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, - unsigned int idx); -struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, - u8 *len_ptr); -unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); -void can_free_echo_skb(struct net_device *dev, unsigned int idx); - #ifdef CONFIG_OF void of_can_transceiver(struct net_device *dev); #else static inline void of_can_transceiver(struct net_device *dev) { } #endif -struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); -struct sk_buff *alloc_canfd_skb(struct net_device *dev, - struct canfd_frame **cfd); -struct sk_buff *alloc_can_err_skb(struct net_device *dev, - struct can_frame **cf); - #endif /* !_CAN_DEV_H */ diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h index fc61cf4eff1c..c90ebbd3008c 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -16,6 +16,19 @@ #include #include +void can_flush_echo_skb(struct net_device *dev); +int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, + unsigned int idx); +struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, + u8 *len_ptr); +unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); +void can_free_echo_skb(struct net_device *dev, unsigned int idx); +struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); +struct sk_buff *alloc_canfd_skb(struct net_device *dev, + struct canfd_frame **cfd); +struct sk_buff *alloc_can_err_skb(struct net_device *dev, + struct can_frame **cf); + /* * The struct can_skb_priv is used to transport additional information along * with the stored struct can(fd)_frame that can not be contained in existing @@ -74,4 +87,68 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb) return nskb; } +/* Check for outgoing skbs that have not been created by the CAN subsystem */ +static inline bool can_skb_headroom_valid(struct net_device *dev, + struct sk_buff *skb) +{ + /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */ + if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv))) + return false; + + /* af_packet does not apply CAN skb specific settings */ + if (skb->ip_summed == CHECKSUM_NONE) { + /* init headroom */ + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + + /* perform proper loopback on capable devices */ + if (dev->flags & IFF_ECHO) + skb->pkt_type = PACKET_LOOPBACK; + else + skb->pkt_type = PACKET_HOST; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + } + + return true; +} + +/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ +static inline bool can_dropped_invalid_skb(struct net_device *dev, + struct sk_buff *skb) +{ + const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + + if (skb->protocol == htons(ETH_P_CAN)) { + if (unlikely(skb->len != CAN_MTU || + cfd->len > CAN_MAX_DLEN)) + goto inval_skb; + } else if (skb->protocol == htons(ETH_P_CANFD)) { + if (unlikely(skb->len != CANFD_MTU || + cfd->len > CANFD_MAX_DLEN)) + goto inval_skb; + } else + goto inval_skb; + + if (!can_skb_headroom_valid(dev, skb)) + goto inval_skb; + + return false; + +inval_skb: + kfree_skb(skb); + dev->stats.tx_dropped++; + return true; +} + +static inline bool can_is_canfd_skb(const struct sk_buff *skb) +{ + /* the CAN specific type of skb is identified by its data length */ + return skb->len == CANFD_MTU; +} + #endif /* !_CAN_SKB_H */