diff options
author | Oliver Hartkopp <socketcan@hartkopp.net> | 2022-09-12 19:07:20 +0200 |
---|---|---|
committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2022-09-15 09:08:08 +0200 |
commit | 467ef4c7b9d1c22ee64342804bf92549d765df14 (patch) | |
tree | 9d8fc4832f3658d85761bc85f2166b1731ded134 /include/linux/can | |
parent | 96a7457a14d9cf98cf58de1e26c03180e0f28141 (diff) |
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>
Diffstat (limited to 'include/linux/can')
-rw-r--r-- | include/linux/can/skb.h | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h index 27ebfc28510f..ddffc2fc008c 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -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 */ |