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>

2 files changed, 4 insertions, 4 deletions

diff --git a/drivers/nfc/microread/i2c.c b/drivers/nfc/microread/i2c.c
index e0e8afd27849..8e328c36a816 100644
--- a/drivers/nfc/microread/i2c.c
+++ b/drivers/nfc/microread/i2c.c
@@ -75,7 +75,7 @@ static void microread_i2c_add_len_crc(struct sk_buff *skb)
 	for (i = 0; i < skb->len; i++)
 		crc = crc ^ skb->data[i];
 
-	*skb_put(skb, 1) = crc;
+	*(u8 *)skb_put(skb, 1) = crc;
 }
 
 static void microread_i2c_remove_len_crc(struct sk_buff *skb)
@@ -173,7 +173,7 @@ static int microread_i2c_read(struct microread_i2c_phy *phy,
 		goto flush;
 	}
 
-	*skb_put(*skb, 1) = len;
+	*(u8 *)skb_put(*skb, 1) = len;
 
 	r = i2c_master_recv(client, skb_put(*skb, len), len);
 	if (r != len) {
diff --git a/drivers/nfc/microread/microread.c b/drivers/nfc/microread/microread.c
index f454dc68cc03..9d0dd1be0923 100644
--- a/drivers/nfc/microread/microread.c
+++ b/drivers/nfc/microread/microread.c
@@ -441,8 +441,8 @@ static int microread_im_transceive(struct nfc_hci_dev *hdev,
 
 		crc = crc_ccitt(0xffff, skb->data, skb->len);
 		crc = ~crc;
-		*skb_put(skb, 1) = crc & 0xff;
-		*skb_put(skb, 1) = crc >> 8;
+		*(u8 *)skb_put(skb, 1) = crc & 0xff;
+		*(u8 *)skb_put(skb, 1) = crc >> 8;
 		break;
 	case MICROREAD_GATE_ID_MREAD_NFC_T3:
 		control_bits = 0xDB;