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>

drivers/net/wireless/intel/ipw2x00/ipw2200.c

@@ -10274,8 +10274,9 @@ static int ipw_tx_skb(struct ipw_priv *priv, struct libipw_txb *txb,
 
 				printk(KERN_INFO "Adding frag %d %d...\n",
 				       j, size);
-				memcpy(skb_put(skb, size),
-				       txb->fragments[j]->data + hdr_len, size);
+				skb_put_data(skb,
+					     txb->fragments[j]->data + hdr_len,
+					     size);
 			}
 			dev_kfree_skb_any(txb->fragments[i]);
 			txb->fragments[i] = skb;

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 */

drivers/net/wireless/intel/iwlegacy/3945.c

@@ -520,7 +520,7 @@ il3945_pass_packet_to_mac80211(struct il_priv *il, struct il_rx_buf *rxb,
 	 * and do not consume a full page
 	 */
 	if (len <= SMALL_PACKET_SIZE) {
-		memcpy(skb_put(skb, len), rx_hdr->payload, len);
+		skb_put_data(skb, rx_hdr->payload, len);
 	} else {
 		skb_add_rx_frag(skb, 0, rxb->page,
 				(void *)rx_hdr->payload - (void *)pkt, len,

drivers/net/wireless/intel/iwlegacy/4965-mac.c

@@ -606,7 +606,7 @@ il4965_pass_packet_to_mac80211(struct il_priv *il, struct ieee80211_hdr *hdr,
 	}
 
 	if (len <= SMALL_PACKET_SIZE) {
-		memcpy(skb_put(skb, len), hdr, len);
+		skb_put_data(skb, hdr, len);
 	} else {
 		skb_add_rx_frag(skb, 0, rxb->page, (void *)hdr - rxb_addr(rxb),
 				len, PAGE_SIZE << il->hw_params.rx_page_order);

drivers/net/wireless/intel/iwlwifi/dvm/rx.c

@@ -657,7 +657,7 @@ static void iwlagn_pass_packet_to_mac80211(struct iwl_priv *priv,
 	 */
 	hdrlen = (len <= skb_tailroom(skb)) ? len : sizeof(*hdr);
 
-	memcpy(skb_put(skb, hdrlen), hdr, hdrlen);
+	skb_put_data(skb, hdr, hdrlen);
 	fraglen = len - hdrlen;
 
 	if (fraglen) {

drivers/net/wireless/intel/iwlwifi/dvm/tx.c

@@ -319,8 +319,7 @@ int iwlagn_tx_skb(struct iwl_priv *priv,
 		if (noa_data &&
 		    pskb_expand_head(skb, 0, noa_data->length,
 				     GFP_ATOMIC) == 0) {
-			memcpy(skb_put(skb, noa_data->length),
-			       noa_data->data, noa_data->length);
+			skb_put_data(skb, noa_data->data, noa_data->length);
 			hdr = (struct ieee80211_hdr *)skb->data;
 		}
 	}

drivers/net/wireless/intel/iwlwifi/mvm/d3.c

@@ -1431,7 +1431,7 @@ static void iwl_mvm_report_wakeup_reasons(struct iwl_mvm *mvm,
 			if (!pkt)
 				goto report;
 
-			memcpy(skb_put(pkt, hdrlen), pktdata, hdrlen);
+			skb_put_data(pkt, pktdata, hdrlen);
 			pktdata += hdrlen;
 			pktsize -= hdrlen;
 
@@ -1463,7 +1463,7 @@ static void iwl_mvm_report_wakeup_reasons(struct iwl_mvm *mvm,
 			pktsize -= ivlen + icvlen;
 			pktdata += ivlen;
 
-			memcpy(skb_put(pkt, pktsize), pktdata, pktsize);
+			skb_put_data(pkt, pktdata, pktsize);
 
 			if (ieee80211_data_to_8023(pkt, vif->addr, vif->type))
 				goto report;

drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c

@@ -1596,7 +1596,7 @@ void iwl_mvm_rx_stored_beacon_notif(struct iwl_mvm *mvm,
 					       rx_status.band);
 
 	/* copy the data */
-	memcpy(skb_put(skb, size), sb->data, size);
+	skb_put_data(skb, sb->data, size);
 	memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
 
 	/* pass it as regular rx to mac80211 */

drivers/net/wireless/intel/iwlwifi/mvm/rx.c

@@ -133,7 +133,7 @@ static void iwl_mvm_pass_packet_to_mac80211(struct iwl_mvm *mvm,
 	 */
 	hdrlen = (len <= skb_tailroom(skb)) ? len : hdrlen + crypt_len + 8;
 
-	memcpy(skb_put(skb, hdrlen), hdr, hdrlen);
+	skb_put_data(skb, hdr, hdrlen);
 	fraglen = len - hdrlen;
 
 	if (fraglen) {

drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c

@@ -183,9 +183,8 @@ static void iwl_mvm_create_skb(struct sk_buff *skb, struct ieee80211_hdr *hdr,
 	 * present before copying packet data.
 	 */
 	hdrlen += crypt_len;
-	memcpy(skb_put(skb, hdrlen), hdr, hdrlen);
-	memcpy(skb_put(skb, headlen - hdrlen), (u8 *)hdr + hdrlen + pad_len,
-	       headlen - hdrlen);
+	skb_put_data(skb, hdr, hdrlen);
+	skb_put_data(skb, (u8 *)hdr + hdrlen + pad_len, headlen - hdrlen);
 
 	fraglen = len - headlen;
 

drivers/net/wireless/intel/iwlwifi/pcie/tx.c

@@ -2141,8 +2141,7 @@ static int iwl_fill_data_tbs_amsdu(struct iwl_trans *trans, struct sk_buff *skb,
 							htons(ETH_P_IPV6),
 						    data_left);
 
-			memcpy(skb_put(csum_skb, tcp_hdrlen(skb)),
-			       tcph, tcp_hdrlen(skb));
+			skb_put_data(csum_skb, tcph, tcp_hdrlen(skb));
 			skb_reset_transport_header(csum_skb);
 			csum_skb->csum_start =
 				(unsigned char *)tcp_hdr(csum_skb) -
@@ -2176,7 +2175,7 @@ static int iwl_fill_data_tbs_amsdu(struct iwl_trans *trans, struct sk_buff *skb,
 			dma_addr_t tb_phys;
 
 			if (trans_pcie->sw_csum_tx)
-				memcpy(skb_put(csum_skb, size), tso.data, size);
+				skb_put_data(csum_skb, tso.data, size);
 
 			tb_phys = dma_map_single(trans->dev, tso.data,
 						 size, DMA_TO_DEVICE);