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, 2 insertions, 4 deletions

diff --git a/drivers/net/wireless/intel/ipw2x00/libipw_tx.c b/drivers/net/wireless/intel/ipw2x00/libipw_tx.c
index 048f1e3ada11..5339d1eeb2f7 100644
--- a/drivers/net/wireless/intel/ipw2x00/libipw_tx.c
+++ b/drivers/net/wireless/intel/ipw2x00/libipw_tx.c
@@ -359,7 +359,7 @@ netdev_tx_t libipw_xmit(struct sk_buff *skb, struct net_device *dev)
 			goto failed;
 
 		skb_reserve(skb_new, crypt->ops->extra_msdu_prefix_len);
-		memcpy(skb_put(skb_new, hdr_len), &header, hdr_len);
+		skb_put_data(skb_new, &header, hdr_len);
 		snapped = 1;
 		libipw_copy_snap(skb_put(skb_new, SNAP_SIZE + sizeof(u16)),
 				    ether_type);
@@ -470,9 +470,7 @@ netdev_tx_t libipw_xmit(struct sk_buff *skb, struct net_device *dev)
 			skb_reserve(skb_frag,
 				    crypt->ops->extra_mpdu_prefix_len);
 
-		frag_hdr =
-		    (struct libipw_hdr_3addrqos *)skb_put(skb_frag, hdr_len);
-		memcpy(frag_hdr, &header, hdr_len);
+		frag_hdr = skb_put_data(skb_frag, &header, hdr_len);
 
 		/* If this is not the last fragment, then add the MOREFRAGS
 		 * bit to the frame control */