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>

2 files changed, 14 insertions, 14 deletions

diff --git a/drivers/net/wireless/zydas/zd1201.c b/drivers/net/wireless/zydas/zd1201.c
index de7ff395977a..7f586d76cf17 100644
--- a/drivers/net/wireless/zydas/zd1201.c
+++ b/drivers/net/wireless/zydas/zd1201.c
@@ -326,13 +326,13 @@ static void zd1201_usbrx(struct urb *urb)
 			if (!(skb = dev_alloc_skb(datalen+24)))
 				goto resubmit;
 			
-			memcpy(skb_put(skb, 2), &data[datalen-16], 2);
-			memcpy(skb_put(skb, 2), &data[datalen-2], 2);
-			memcpy(skb_put(skb, 6), &data[datalen-14], 6);
-			memcpy(skb_put(skb, 6), &data[datalen-22], 6);
-			memcpy(skb_put(skb, 6), &data[datalen-8], 6);
-			memcpy(skb_put(skb, 2), &data[datalen-24], 2);
-			memcpy(skb_put(skb, len), data, len);
+			skb_put_data(skb, &data[datalen - 16], 2);
+			skb_put_data(skb, &data[datalen - 2], 2);
+			skb_put_data(skb, &data[datalen - 14], 6);
+			skb_put_data(skb, &data[datalen - 22], 6);
+			skb_put_data(skb, &data[datalen - 8], 6);
+			skb_put_data(skb, &data[datalen - 24], 2);
+			skb_put_data(skb, data, len);
 			skb->protocol = eth_type_trans(skb, zd->dev);
 			zd->dev->stats.rx_packets++;
 			zd->dev->stats.rx_bytes += skb->len;
@@ -359,9 +359,9 @@ static void zd1201_usbrx(struct urb *urb)
 				frag->skb = skb;
 				frag->seq = seq & IEEE80211_SCTL_SEQ;
 				skb_reserve(skb, 2);
-				memcpy(skb_put(skb, 12), &data[datalen-14], 12);
-				memcpy(skb_put(skb, 2), &data[6], 2);
-				memcpy(skb_put(skb, len), data+8, len);
+				skb_put_data(skb, &data[datalen - 14], 12);
+				skb_put_data(skb, &data[6], 2);
+				skb_put_data(skb, data + 8, len);
 				hlist_add_head(&frag->fnode, &zd->fraglist);
 				goto resubmit;
 			}
@@ -385,9 +385,9 @@ static void zd1201_usbrx(struct urb *urb)
 			if (!skb)
 				goto resubmit;
 			skb_reserve(skb, 2);
-			memcpy(skb_put(skb, 12), &data[datalen-14], 12);
-			memcpy(skb_put(skb, 2), &data[6], 2);
-			memcpy(skb_put(skb, len), data+8, len);
+			skb_put_data(skb, &data[datalen - 14], 12);
+			skb_put_data(skb, &data[6], 2);
+			skb_put_data(skb, data + 8, len);
 		}
 		skb->protocol = eth_type_trans(skb, zd->dev);
 		zd->dev->stats.rx_packets++;
diff --git a/drivers/net/wireless/zydas/zd1211rw/zd_mac.c b/drivers/net/wireless/zydas/zd1211rw/zd_mac.c
index fe6517a621b0..2d929d2edb00 100644
--- a/drivers/net/wireless/zydas/zd1211rw/zd_mac.c
+++ b/drivers/net/wireless/zydas/zd1211rw/zd_mac.c
@@ -1103,7 +1103,7 @@ int zd_mac_rx(struct ieee80211_hw *hw, const u8 *buffer, unsigned int length)
 	}
 
 	/* FIXME : could we avoid this big memcpy ? */
-	memcpy(skb_put(skb, length), buffer, length);
+	skb_put_data(skb, buffer, length);
 
 	memcpy(IEEE80211_SKB_RXCB(skb), &stats, sizeof(stats));
 	ieee80211_rx_irqsafe(hw, skb);