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, 8 insertions, 9 deletions

diff --git a/net/802/garp.c b/net/802/garp.c
index b38ee6d..a9a2665 100644
--- a/net/802/garp.c
+++ b/net/802/garp.c
@@ -221,7 +221,7 @@ static int garp_pdu_init(struct garp_applicant *app)
 	skb->protocol = htons(ETH_P_802_2);
 	skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE);
 
-	gp = (struct garp_pdu_hdr *)__skb_put(skb, sizeof(*gp));
+	gp = __skb_put(skb, sizeof(*gp));
 	put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol);
 
 	app->pdu = skb;
@@ -268,7 +268,7 @@ static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype)
 
 	if (skb_tailroom(app->pdu) < sizeof(*gm))
 		return -1;
-	gm = (struct garp_msg_hdr *)__skb_put(app->pdu, sizeof(*gm));
+	gm = __skb_put(app->pdu, sizeof(*gm));
 	gm->attrtype = attrtype;
 	garp_cb(app->pdu)->cur_type = attrtype;
 	return 0;
@@ -299,7 +299,7 @@ again:
 	len = sizeof(*ga) + attr->dlen;
 	if (skb_tailroom(app->pdu) < len)
 		goto queue;
-	ga = (struct garp_attr_hdr *)__skb_put(app->pdu, len);
+	ga = __skb_put(app->pdu, len);
 	ga->len   = len;
 	ga->event = event;
 	memcpy(ga->data, attr->data, attr->dlen);
diff --git a/net/802/mrp.c b/net/802/mrp.c
index 72db278..be4dd31 100644
--- a/net/802/mrp.c
+++ b/net/802/mrp.c
@@ -311,7 +311,7 @@ static int mrp_pdu_init(struct mrp_applicant *app)
 	skb_reset_network_header(skb);
 	skb_reset_transport_header(skb);
 
-	ph = (struct mrp_pdu_hdr *)__skb_put(skb, sizeof(*ph));
+	ph = __skb_put(skb, sizeof(*ph));
 	ph->version = app->app->version;
 
 	app->pdu = skb;
@@ -324,7 +324,7 @@ static int mrp_pdu_append_end_mark(struct mrp_applicant *app)
 
 	if (skb_tailroom(app->pdu) < sizeof(*endmark))
 		return -1;
-	endmark = (__be16 *)__skb_put(app->pdu, sizeof(*endmark));
+	endmark = __skb_put(app->pdu, sizeof(*endmark));
 	put_unaligned(MRP_END_MARK, endmark);
 	return 0;
 }
@@ -368,7 +368,7 @@ static int mrp_pdu_append_msg_hdr(struct mrp_applicant *app,
 
 	if (skb_tailroom(app->pdu) < sizeof(*mh))
 		return -1;
-	mh = (struct mrp_msg_hdr *)__skb_put(app->pdu, sizeof(*mh));
+	mh = __skb_put(app->pdu, sizeof(*mh));
 	mh->attrtype = attrtype;
 	mh->attrlen = attrlen;
 	mrp_cb(app->pdu)->mh = mh;
@@ -382,8 +382,7 @@ static int mrp_pdu_append_vecattr_hdr(struct mrp_applicant *app,
 
 	if (skb_tailroom(app->pdu) < sizeof(*vah) + attrlen)
 		return -1;
-	vah = (struct mrp_vecattr_hdr *)__skb_put(app->pdu,
-						  sizeof(*vah) + attrlen);
+	vah = __skb_put(app->pdu, sizeof(*vah) + attrlen);
 	put_unaligned(0, &vah->lenflags);
 	memcpy(vah->firstattrvalue, firstattrvalue, attrlen);
 	mrp_cb(app->pdu)->vah = vah;
@@ -435,7 +434,7 @@ again:
 	if (!pos) {
 		if (skb_tailroom(app->pdu) < sizeof(u8))
 			goto queue;
-		vaevents = (u8 *)__skb_put(app->pdu, sizeof(u8));
+		vaevents = __skb_put(app->pdu, sizeof(u8));
 	} else {
 		vaevents = (u8 *)(skb_tail_pointer(app->pdu) - sizeof(u8));
 	}