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, 3 deletions

diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c
index 961c07ee47b7..aea0c9616ea5 100644
--- a/drivers/isdn/hardware/mISDN/hfcmulti.c
+++ b/drivers/isdn/hardware/mISDN/hfcmulti.c
@@ -1926,7 +1926,7 @@ hfcmulti_dtmf(struct hfc_multi *hc)
 			hh = mISDN_HEAD_P(skb);
 			hh->prim = PH_CONTROL_IND;
 			hh->id = DTMF_HFC_COEF;
-			memcpy(skb_put(skb, 512), hc->chan[ch].coeff, 512);
+			skb_put_data(skb, hc->chan[ch].coeff, 512);
 			recv_Bchannel_skb(bch, skb);
 		}
 	}
@@ -2332,8 +2332,7 @@ next_frame:
 				skb = *sp;
 				*sp = mI_alloc_skb(skb->len, GFP_ATOMIC);
 				if (*sp) {
-					memcpy(skb_put(*sp, skb->len),
-					       skb->data, skb->len);
+					skb_put_data(*sp, skb->data, skb->len);
 					skb_trim(skb, 0);
 				} else {
 					printk(KERN_DEBUG "%s: No mem\n",