Am 06.11.20 um 18:58 schrieb Marc Kleine-Budde: > On 11/6/20 6:02 PM, Gerhard Uttenthaler wrote: >> Signed-off-by: Gerhard Uttenthaler <uttenthaler@xxxxxxxxxxxxxxxx> >> --- >> drivers/net/can/usb/ems_usb.c | 31 +++++++++++++++++++++++-------- >> 1 file changed, 23 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/net/can/usb/ems_usb.c b/drivers/net/can/usb/ems_usb.c >> index b51a5eb65946..c464d644c833 100644 >> --- a/drivers/net/can/usb/ems_usb.c >> +++ b/drivers/net/can/usb/ems_usb.c >> @@ -902,25 +902,37 @@ static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *ne >> struct can_frame *cf = (struct can_frame *)skb->data; >> struct ems_cpc_msg *msg; >> struct urb *urb; >> - u8 *buf; >> int i, err; >> - size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN >> - + sizeof(struct cpc_can_msg); >> + >> + u8 *buf; >> + size_t buf_size; >> + size_t buf_len = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN; >> >> if (can_dropped_invalid_skb(netdev, skb)) >> return NETDEV_TX_OK; >> >> - /* create a URB, and a buffer for it, and copy the data to the URB */ >> + buf_size = CPC_HEADER_SIZE + >> + CPC_MSG_HEADER_LEN + >> + sizeof(struct cpc_can_msg); > > does it make sense to only allocate the length of the buffer needed to hold the > data?I have considered that, but actual length depends on DLC, however not when the frame is an RTR and this is different for Classic and FD. I think code will get more complicated with the benefit only to save a few bytes. -- Gerhard -- EMS Dr. Thomas Wuensche e.K. Sonnenhang 3 85304 Ilmmuenster HR Ingolstadt, HRA 170106 Phone: +49-8441-490260 Fax : +49-8441-81860 http://www.ems-wuensche.com
