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, 2 deletions

diff --git a/drivers/staging/rtl8723bs/os_dep/recv_linux.c b/drivers/staging/rtl8723bs/os_dep/recv_linux.c
index e731ab4e2bd7..1a6443dc3ff0 100644
--- a/drivers/staging/rtl8723bs/os_dep/recv_linux.c
+++ b/drivers/staging/rtl8723bs/os_dep/recv_linux.c
@@ -82,8 +82,8 @@ _pkt *rtw_os_alloc_msdu_pkt(union recv_frame *prframe, u16 nSubframe_Length, u8
 	if (sub_skb)
 	{
 		skb_reserve(sub_skb, 12);
-		data_ptr = (u8 *)skb_put(sub_skb, nSubframe_Length);
-		memcpy(data_ptr, (pdata + ETH_HLEN), nSubframe_Length);
+		data_ptr = skb_put_data(sub_skb, (pdata + ETH_HLEN),
+					nSubframe_Length);
 	}
 	else
 	{