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: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Oliver Hartkopp 2022-09-12 19:07:20 +02:00 committed by Marc Kleine-Budde
parent 96a7457a14
commit 467ef4c7b9
3 changed files with 28 additions and 10 deletions

View file

@ -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);

View file

@ -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)

View file

@ -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 */