networking: make skb_push & __skb_push 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 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_push, __skb_push, skb_push_rcsum };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

    @@
    expression SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    @@
    - fn(SKB, LEN)[0]
    + *(u8 *)fn(SKB, LEN)

Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Johannes Berg
2017-06-16 14:29:23 +02:00
committed by David S. Miller
parent af72868b90
commit d58ff35122
126 changed files with 204 additions and 234 deletions

View File

@@ -1490,7 +1490,7 @@ ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
/* check if we should pass this packet */
/* the filter instructions are constructed assuming
a four-byte PPP header on each packet */
*skb_push(skb, 2) = 1;
*(u8 *)skb_push(skb, 2) = 1;
if (ppp->pass_filter &&
BPF_PROG_RUN(ppp->pass_filter, skb) == 0) {
if (ppp->debug & 1)
@@ -2133,7 +2133,7 @@ ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
if (skb_unclone(skb, GFP_ATOMIC))
goto err;
*skb_push(skb, 2) = 0;
*(u8 *)skb_push(skb, 2) = 0;
if (ppp->pass_filter &&
BPF_PROG_RUN(ppp->pass_filter, skb) == 0) {
if (ppp->debug & 1)
@@ -2267,7 +2267,7 @@ ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
* Do protocol ID decompression on the first fragment of each packet.
*/
if ((PPP_MP_CB(skb)->BEbits & B) && (skb->data[0] & 1))
*skb_push(skb, 1) = 0;
*(u8 *)skb_push(skb, 1) = 0;
/*
* Expand sequence number to 32 bits, making it as close