can: rework skb reserved data handling

Added accessor and skb_reserve helpers for struct can_skb_priv.
Removed pointless skb_headroom() check.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
CC: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 7 insertions, 9 deletions

diff --git a/net/can/bcm.c b/net/can/bcm.c
index ccc27b9e8384..28e12d18f0f1 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -261,8 +261,8 @@ static void bcm_can_tx(struct bcm_op *op)
         if (!skb)
                 goto out;
 
-        skb_reserve(skb, sizeof(struct can_skb_priv));
-        ((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+        can_skb_reserve(skb);
+        can_skb_prv(skb)->ifindex = dev->ifindex;
 
         memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
 
@@ -1207,7 +1207,7 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
         if (!skb)
                 return -ENOMEM;
 
-        skb_reserve(skb, sizeof(struct can_skb_priv));
+        can_skb_reserve(skb);
 
         err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
         if (err < 0) {
@@ -1221,7 +1221,7 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
                 return -ENODEV;
         }
 
-        ((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+        can_skb_prv(skb)->ifindex = dev->ifindex;
         skb->dev = dev;
         skb->sk  = sk;
         err = can_send(skb, 1); /* send with loopback */
diff --git a/net/can/gw.c b/net/can/gw.c
index acdd4656cc3b..c185fcd5e828 100644
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -381,9 +381,7 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
 
         /* is sending the skb back to the incoming interface not allowed? */
         if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) &&
-            skb_headroom(skb) == sizeof(struct can_skb_priv) &&
-            (((struct can_skb_priv *)(skb->head))->ifindex ==
-             gwj->dst.dev->ifindex))
+            can_skb_prv(skb)->ifindex == gwj->dst.dev->ifindex)
                 return;
 
         /*
diff --git a/net/can/raw.c b/net/can/raw.c
index 5d860e8dcc52..c1764e41ddaf 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -705,8 +705,8 @@ static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
         if (!skb)
                 goto put_dev;
 
-        skb_reserve(skb, sizeof(struct can_skb_priv));
-        ((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+        can_skb_reserve(skb);
+        can_skb_prv(skb)->ifindex = dev->ifindex;
 
         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
         if (err < 0)