Commit 467ef4c7 authored by Oliver Hartkopp's avatar Oliver Hartkopp Committed by Marc Kleine-Budde
Browse files

can: skb: add skb CAN frame data length helpers 



Add two helpers to retrieve the data length from CAN sk_buffs and prepare
the length information to be a uint16 value for the CAN XL support.

Acked-by: default avatarVincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-3-socketcan@hartkopp.net


Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 96a7457a

drivers/net/can/dev/rx-offload.c

+1 −1
Original line number Diff line number Diff line
@@ -247,7 +247,7 @@ unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, 
	struct net_device *dev = offload->dev;

	struct net_device_stats *stats = &dev->stats;

	struct sk_buff *skb;

	u8 len;

	unsigned int len;

	int err;



	skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr);

drivers/net/can/dev/skb.c

+4 −8
Original line number Diff line number Diff line
@@ -91,8 +91,8 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 
EXPORT_SYMBOL_GPL(can_put_echo_skb);



struct sk_buff *

__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr,

		   unsigned int *frame_len_ptr)

__can_get_echo_skb(struct net_device *dev, unsigned int idx,

		   unsigned int *len_ptr, unsigned int *frame_len_ptr)

{

	struct can_priv *priv = netdev_priv(dev);
@@ -108,16 +108,12 @@ __can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr, 
		 */

		struct sk_buff *skb = priv->echo_skb[idx];

		struct can_skb_priv *can_skb_priv = can_skb_prv(skb);

		struct canfd_frame *cf = (struct canfd_frame *)skb->data;



		if (skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)

			skb_tstamp_tx(skb, skb_hwtstamps(skb));



		/* get the real payload length for netdev statistics */

		if (cf->can_id & CAN_RTR_FLAG)

			*len_ptr = 0;

		else

			*len_ptr = cf->len;

		*len_ptr = can_skb_get_data_len(skb);



		if (frame_len_ptr)

			*frame_len_ptr = can_skb_priv->frame_len;
@@ -147,7 +143,7 @@ unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx, 
			      unsigned int *frame_len_ptr)

{

	struct sk_buff *skb;

	u8 len;

	unsigned int len;



	skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr);

	if (!skb)

include/linux/can/skb.h

+23 −1
Original line number Diff line number Diff line
@@ -20,7 +20,8 @@ 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, unsigned int frame_len);

struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,

				   u8 *len_ptr, unsigned int *frame_len_ptr);

				   unsigned int *len_ptr,

				   unsigned int *frame_len_ptr);

unsigned int __must_check can_get_echo_skb(struct net_device *dev,

					   unsigned int idx,

					   unsigned int *frame_len_ptr);
@@ -113,4 +114,25 @@ static inline bool can_is_canfd_skb(const struct sk_buff *skb) 
	return (skb->len == CANFD_MTU && cfd->len <= CANFD_MAX_DLEN);

}



/* get length element value from can[fd]_frame structure */

static inline unsigned int can_skb_get_len_val(struct sk_buff *skb)

{

	const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;



	return cfd->len;

}



/* get needed data length inside CAN frame for all frame types (RTR aware) */

static inline unsigned int can_skb_get_data_len(struct sk_buff *skb)

{

	unsigned int len = can_skb_get_len_val(skb);

	const struct can_frame *cf = (struct can_frame *)skb->data;



	/* RTR frames have an actual length of zero */

	if (can_is_can_skb(skb) && cf->can_id & CAN_RTR_FLAG)

		return 0;



	return len;

}



#endif /* !_CAN_SKB_H */