Commit 92a31782 authored by Dario Binacchi's avatar Dario Binacchi Committed by Marc Kleine-Budde
Browse files

can: slcan: use the alloc_can_skb() helper 

It is used successfully by most (if not all) CAN device drivers. It
allows to remove replicated code.

Link: https://lore.kernel.org/all/20220628163137.413025-4-dario.binacchi@amarulasolutions.com


Signed-off-by: default avatarDario Binacchi <dario.binacchi@amarulasolutions.com>
Tested-by: default avatarJeroen Hofstee <jhofstee@victronenergy.com>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent da6788ea

drivers/net/can/slcan.c

+33 −37
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ 
#include <linux/kernel.h>

#include <linux/workqueue.h>

#include <linux/can.h>

#include <linux/can/dev.h>

#include <linux/can/skb.h>

#include <linux/can/can-ml.h>
@@ -143,85 +144,80 @@ static struct net_device **slcan_devs; 
static void slc_bump(struct slcan *sl)

{

	struct sk_buff *skb;

	struct can_frame cf;

	struct can_frame *cf;

	int i, tmp;

	u32 tmpid;

	char *cmd = sl->rbuff;



	memset(&cf, 0, sizeof(cf));

	skb = alloc_can_skb(sl->dev, &cf);

	if (unlikely(!skb)) {

		sl->dev->stats.rx_dropped++;

		return;

	}



	switch (*cmd) {

	case 'r':

		cf.can_id = CAN_RTR_FLAG;

		cf->can_id = CAN_RTR_FLAG;

		fallthrough;

	case 't':

		/* store dlc ASCII value and terminate SFF CAN ID string */

		cf.len = sl->rbuff[SLC_CMD_LEN + SLC_SFF_ID_LEN];

		cf->len = sl->rbuff[SLC_CMD_LEN + SLC_SFF_ID_LEN];

		sl->rbuff[SLC_CMD_LEN + SLC_SFF_ID_LEN] = 0;

		/* point to payload data behind the dlc */

		cmd += SLC_CMD_LEN + SLC_SFF_ID_LEN + 1;

		break;

	case 'R':

		cf.can_id = CAN_RTR_FLAG;

		cf->can_id = CAN_RTR_FLAG;

		fallthrough;

	case 'T':

		cf.can_id |= CAN_EFF_FLAG;

		cf->can_id |= CAN_EFF_FLAG;

		/* store dlc ASCII value and terminate EFF CAN ID string */

		cf.len = sl->rbuff[SLC_CMD_LEN + SLC_EFF_ID_LEN];

		cf->len = sl->rbuff[SLC_CMD_LEN + SLC_EFF_ID_LEN];

		sl->rbuff[SLC_CMD_LEN + SLC_EFF_ID_LEN] = 0;

		/* point to payload data behind the dlc */

		cmd += SLC_CMD_LEN + SLC_EFF_ID_LEN + 1;

		break;

	default:

		return;

		goto decode_failed;

	}



	if (kstrtou32(sl->rbuff + SLC_CMD_LEN, 16, &tmpid))

		return;

		goto decode_failed;



	cf.can_id |= tmpid;

	cf->can_id |= tmpid;



	/* get len from sanitized ASCII value */

	if (cf.len >= '0' && cf.len < '9')

		cf.len -= '0';

	if (cf->len >= '0' && cf->len < '9')

		cf->len -= '0';

	else

		return;

		goto decode_failed;



	/* RTR frames may have a dlc > 0 but they never have any data bytes */

	if (!(cf.can_id & CAN_RTR_FLAG)) {

		for (i = 0; i < cf.len; i++) {

	if (!(cf->can_id & CAN_RTR_FLAG)) {

		for (i = 0; i < cf->len; i++) {

			tmp = hex_to_bin(*cmd++);

			if (tmp < 0)

				return;

			cf.data[i] = (tmp << 4);

				goto decode_failed;



			cf->data[i] = (tmp << 4);

			tmp = hex_to_bin(*cmd++);

			if (tmp < 0)

				return;

			cf.data[i] |= tmp;

				goto decode_failed;



			cf->data[i] |= tmp;

		}

	}



	skb = dev_alloc_skb(sizeof(struct can_frame) +

			    sizeof(struct can_skb_priv));

	if (!skb)

		return;



	skb->dev = sl->dev;

	skb->protocol = htons(ETH_P_CAN);

	skb->pkt_type = PACKET_BROADCAST;

	skb->ip_summed = CHECKSUM_UNNECESSARY;



	can_skb_reserve(skb);

	can_skb_prv(skb)->ifindex = sl->dev->ifindex;

	can_skb_prv(skb)->skbcnt = 0;



	skb_put_data(skb, &cf, sizeof(struct can_frame));



	sl->dev->stats.rx_packets++;

	if (!(cf.can_id & CAN_RTR_FLAG))

		sl->dev->stats.rx_bytes += cf.len;

	if (!(cf->can_id & CAN_RTR_FLAG))

		sl->dev->stats.rx_bytes += cf->len;



	netif_rx(skb);

	return;



decode_failed:

	sl->dev->stats.rx_errors++;

	dev_kfree_skb(skb);

}



/* parse tty input stream */