[NET]: Clean up skb_linearize

The linearisation operation doesn't need to be super-optimised.  So we can
replace __skb_linearize with __pskb_pull_tail which does the same thing but
is more general.

Also, most users of skb_linearize end up testing whether the skb is linear
or not so it helps to make skb_linearize do just that.

Some callers of skb_linearize also use it to copy cloned data, so it's
useful to have a new function skb_linearize_cow to copy the data if it's
either non-linear or cloned.

Last but not least, I've removed the gfp argument since nobody uses it
anymore.  If it's ever needed we can easily add it back.

Misc bugs fixed by this patch:

* via-velocity error handling (also, no SG => no frags)

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 2 insertions, 4 deletions

diff --git a/net/decnet/dn_nsp_in.c b/net/decnet/dn_nsp_in.c
index 547523b41c81..a2ba9db1c376 100644
--- a/net/decnet/dn_nsp_in.c
+++ b/net/decnet/dn_nsp_in.c
@@ -801,8 +801,7 @@ got_it:
                  * We linearize everything except data segments here.
                  */
                 if (cb->nsp_flags & ~0x60) {
-                        if (unlikely(skb_is_nonlinear(skb)) &&
-                            skb_linearize(skb, GFP_ATOMIC) != 0)
+                        if (unlikely(skb_linearize(skb)))
                                 goto free_out;
                 }
 
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index e172cf98d7fc..5abf7057af00 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -629,8 +629,7 @@ int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type
                         padlen);
 
         if (flags & DN_RT_PKT_CNTL) {
-                if (unlikely(skb_is_nonlinear(skb)) &&
-                    skb_linearize(skb, GFP_ATOMIC) != 0)
+                if (unlikely(skb_linearize(skb)))
                         goto dump_it;
 
                 switch(flags & DN_RT_CNTL_MSK) {