can: provide library functions for skb allocation

This patch makes the private functions alloc_can_skb() and
alloc_can_err_skb() of the at91_can driver public and adapts all
drivers to use these. While making the patch I realized, that
the skb's are *not* setup consistently. It's now done as shown
below:

  skb->protocol = htons(ETH_P_CAN);
  skb->pkt_type = PACKET_BROADCAST;
  skb->ip_summed = CHECKSUM_UNNECESSARY;
  *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
  memset(*cf, 0, sizeof(struct can_frame));

The frame is zeroed out to avoid uninitialized data to be passed to
user space. Some drivers or library code did not set "pkt_type" or
"ip_summed". Also,  "__constant_htons()" should not be used for
runtime invocations, as pointed out by David Miller.

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 32 deletions

diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index b13fd91..cbe3fce 100644
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -221,38 +221,6 @@ static inline void set_mb_mode(const struct at91_priv *priv, unsigned int mb,
 	set_mb_mode_prio(priv, mb, mode, 0);
 }
 
-static struct sk_buff *alloc_can_skb(struct net_device *dev,
-		struct can_frame **cf)
-{
-	struct sk_buff *skb;
-
-	skb = netdev_alloc_skb(dev, sizeof(struct can_frame));
-	if (unlikely(!skb))
-		return NULL;
-
-	skb->protocol = htons(ETH_P_CAN);
-	skb->ip_summed = CHECKSUM_UNNECESSARY;
-	*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-
-	return skb;
-}
-
-static struct sk_buff *alloc_can_err_skb(struct net_device *dev,
-		struct can_frame **cf)
-{
-	struct sk_buff *skb;
-
-	skb = alloc_can_skb(dev, cf);
-	if (unlikely(!skb))
-		return NULL;
-
-	memset(*cf, 0, sizeof(struct can_frame));
-	(*cf)->can_id = CAN_ERR_FLAG;
-	(*cf)->can_dlc = CAN_ERR_DLC;
-
-	return skb;
-}
-
 /*
  * Swtich transceiver on or off
  */