networking: introduce and use skb_put_data()

A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 5 deletions

diff --git a/net/decnet/dn_nsp_out.c b/net/decnet/dn_nsp_out.c
index 849805e7af52..b8a558715395 100644
--- a/net/decnet/dn_nsp_out.c
+++ b/net/decnet/dn_nsp_out.c
@@ -533,7 +533,7 @@ void dn_send_conn_conf(struct sock *sk, gfp_t gfp)
 	*skb_put(skb,1) = len;
 
 	if (len > 0)
-		memcpy(skb_put(skb, len), scp->conndata_out.opt_data, len);
+		skb_put_data(skb, scp->conndata_out.opt_data, len);
 
 
 	dn_nsp_send(skb);
@@ -691,22 +691,22 @@ void dn_nsp_send_conninit(struct sock *sk, unsigned char msgflg)
 	aux = scp->accessdata.acc_userl;
 	*skb_put(skb, 1) = aux;
 	if (aux > 0)
-		memcpy(skb_put(skb, aux), scp->accessdata.acc_user, aux);
+		skb_put_data(skb, scp->accessdata.acc_user, aux);
 
 	aux = scp->accessdata.acc_passl;
 	*skb_put(skb, 1) = aux;
 	if (aux > 0)
-		memcpy(skb_put(skb, aux), scp->accessdata.acc_pass, aux);
+		skb_put_data(skb, scp->accessdata.acc_pass, aux);
 
 	aux = scp->accessdata.acc_accl;
 	*skb_put(skb, 1) = aux;
 	if (aux > 0)
-		memcpy(skb_put(skb, aux), scp->accessdata.acc_acc, aux);
+		skb_put_data(skb, scp->accessdata.acc_acc, aux);
 
 	aux = (__u8)le16_to_cpu(scp->conndata_out.opt_optl);
 	*skb_put(skb, 1) = aux;
 	if (aux > 0)
-		memcpy(skb_put(skb, aux), scp->conndata_out.opt_data, aux);
+		skb_put_data(skb, scp->conndata_out.opt_data, aux);
 
 	scp->persist = dn_nsp_persist(sk);
 	scp->persist_fxn = dn_nsp_retrans_conninit;