networking: make skb_put & friends return void pointers

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wireless/ath/ath6kl/debug.c

@@ -348,7 +348,7 @@ void ath6kl_debug_fwlog_event(struct ath6kl *ar, const void *buf, size_t len)
 	if (!skb)
 		return;
 
-	slot = (struct ath6kl_fwlog_slot *) skb_put(skb, slot_len);
+	slot = skb_put(skb, slot_len);
 	slot->timestamp = cpu_to_le32(jiffies);
 	slot->length = cpu_to_le32(len);
 	memcpy(slot->payload, buf, len);

drivers/net/wireless/ath/ath6kl/htc_pipe.c

@@ -1274,8 +1274,7 @@ static int ath6kl_htc_pipe_conn_service(struct htc_target *target,
 		length = sizeof(struct htc_conn_service_msg);
 
 		/* assemble connect service message */
-		conn_msg = (struct htc_conn_service_msg *) skb_put(skb,
-								   length);
+		conn_msg = skb_put(skb, length);
 		if (conn_msg == NULL) {
 			WARN_ON_ONCE(1);
 			status = -EINVAL;
@@ -1504,8 +1503,7 @@ static int ath6kl_htc_pipe_start(struct htc_target *target)
 	skb = packet->skb;
 
 	/* assemble setup complete message */
-	setup = (struct htc_setup_comp_ext_msg *) skb_put(skb,
-							  sizeof(*setup));
+	setup = skb_put(skb, sizeof(*setup));
 	memset(setup, 0, sizeof(struct htc_setup_comp_ext_msg));
 	setup->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
 

drivers/net/wireless/ath/ath9k/htc_hst.c

@@ -156,8 +156,7 @@ static int htc_config_pipe_credits(struct htc_target *target)
 	}
 	skb_reserve(skb, sizeof(struct htc_frame_hdr));
 
-	cp_msg = (struct htc_config_pipe_msg *)
-		skb_put(skb, sizeof(struct htc_config_pipe_msg));
+	cp_msg = skb_put(skb, sizeof(struct htc_config_pipe_msg));
 
 	cp_msg->message_id = cpu_to_be16(HTC_MSG_CONFIG_PIPE_ID);
 	cp_msg->pipe_id = USB_WLAN_TX_PIPE;
@@ -195,8 +194,7 @@ static int htc_setup_complete(struct htc_target *target)
 	}
 	skb_reserve(skb, sizeof(struct htc_frame_hdr));
 
-	comp_msg = (struct htc_comp_msg *)
-		skb_put(skb, sizeof(struct htc_comp_msg));
+	comp_msg = skb_put(skb, sizeof(struct htc_comp_msg));
 	comp_msg->msg_id = cpu_to_be16(HTC_MSG_SETUP_COMPLETE_ID);
 
 	target->htc_flags |= HTC_OP_START_WAIT;
@@ -265,8 +263,7 @@ int htc_connect_service(struct htc_target *target,
 
 	skb_reserve(skb, sizeof(struct htc_frame_hdr));
 
-	conn_msg = (struct htc_conn_svc_msg *)
-			skb_put(skb, sizeof(struct htc_conn_svc_msg));
+	conn_msg = skb_put(skb, sizeof(struct htc_conn_svc_msg));
 	conn_msg->service_id = cpu_to_be16(service_connreq->service_id);
 	conn_msg->msg_id = cpu_to_be16(HTC_MSG_CONNECT_SERVICE_ID);
 	conn_msg->con_flags = cpu_to_be16(service_connreq->con_flags);

drivers/net/wireless/ath/wil6210/wmi.c

@@ -677,7 +677,7 @@ static void wmi_evt_eapol_rx(struct wil6210_priv *wil, int id,
 		return;
 	}
 
-	eth = (struct ethhdr *)skb_put(skb, ETH_HLEN);
+	eth = skb_put(skb, ETH_HLEN);
 	ether_addr_copy(eth->h_dest, ndev->dev_addr);
 	ether_addr_copy(eth->h_source, evt->src_mac);
 	eth->h_proto = cpu_to_be16(ETH_P_PAE);