On 21/03/2020 20.15, Robert Barrows wrote:
You don't use sockets from INSIDE the kernel.
If you want to send CAN frames from inside the kernel you should use the
can_send() function from af_can.c
Great to know! I Will look at that right away, any example(s) you could point
me towards?
You mainly need to look at raw_sendmsg() from linux/net/can/raw.c
Create a skb and set can_skb_reserve() and the other stuff and finally
put your CAN frame content into the skb->data and invoke can_send().
You will at least need
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
#include <linux/can/skb.h>
Of course you don't have a sk reference as you don't have a socket in place.
So you maybe should check the content of alloc_can_skb() from
linux/drivers/net/can/dev.c and use netdev_alloc_skb() or alloc_skb()
instead of sock_alloc_send_skb() which needs sk to take care of socket
specific memory quotas.
If you are unsure just post the code for a review.
Best,
Oliver
