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, 3 insertions, 3 deletions

diff --git a/net/nfc/hci/core.c b/net/nfc/hci/core.c
index 2b0f0ac498d2..8741ad47a6fb 100644
--- a/net/nfc/hci/core.c
+++ b/net/nfc/hci/core.c
@@ -878,9 +878,9 @@ static void nfc_hci_recv_from_llc(struct nfc_hci_dev *hdev, struct sk_buff *skb)
 
 		skb_queue_walk(&hdev->rx_hcp_frags, frag_skb) {
 			msg_len = frag_skb->len - NFC_HCI_HCP_PACKET_HEADER_LEN;
-			memcpy(skb_put(hcp_skb, msg_len),
-			       frag_skb->data + NFC_HCI_HCP_PACKET_HEADER_LEN,
-			       msg_len);
+			skb_put_data(hcp_skb,
+				     frag_skb->data + NFC_HCI_HCP_PACKET_HEADER_LEN,
+				     msg_len);
 		}
 
 		skb_queue_purge(&hdev->rx_hcp_frags);