net: add alloc_skb_with_frags() helper

Extract from sock_alloc_send_pskb() code building skb with frags,
so that we can reuse this in other contexts.

Intent is to use it from tcp_send_rcvq(), tcp_collapse(), ...

We also want to replace some skb_linearize() calls to a more reliable
strategy in pathological cases where we need to reduce number of frags.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 756e3d057e84..f1bfa3781c75 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -769,6 +769,12 @@ static inline struct sk_buff *alloc_skb(unsigned int size,
         return __alloc_skb(size, priority, 0, NUMA_NO_NODE);
 }
 
+struct sk_buff *alloc_skb_with_frags(unsigned long header_len,
+                                     unsigned long data_len,
+                                     int max_page_order,
+                                     int *errcode,
+                                     gfp_t gfp_mask);
+
 static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
                                                gfp_t priority)
 {