net: Export skb_zerocopy() to zerocopy from one skb to another

[karo-tx-linux.git] / net / netfilter / nfnetlink_queue_core.c

diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c
index ae2e5c11d01ac9887c5158d0084f193c624373ef..615ee12647ae95b56997e69597a7881c740b2944 100644 (file)
--- a/net/netfilter/nfnetlink_queue_core.c
+++ b/net/netfilter/nfnetlink_queue_core.c
@@ -235,51 +235,6 @@ nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
        spin_unlock_bh(&queue->lock);
 }
 
-static void
-nfqnl_zcopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen)
-{
-       int i, j = 0;
-       int plen = 0; /* length of skb->head fragment */
-       struct page *page;
-       unsigned int offset;
-
-       /* dont bother with small payloads */
-       if (len <= skb_tailroom(to)) {
-               skb_copy_bits(from, 0, skb_put(to, len), len);
-               return;
-       }
-
-       if (hlen) {
-               skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
-               len -= hlen;
-       } else {
-               plen = min_t(int, skb_headlen(from), len);
-               if (plen) {
-                       page = virt_to_head_page(from->head);
-                       offset = from->data - (unsigned char *)page_address(page);
-                       __skb_fill_page_desc(to, 0, page, offset, plen);
-                       get_page(page);
-                       j = 1;
-                       len -= plen;
-               }
-       }
-
-       to->truesize += len + plen;
-       to->len += len + plen;
-       to->data_len += len + plen;
-
-       for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
-               if (!len)
-                       break;
-               skb_shinfo(to)->frags[j] = skb_shinfo(from)->frags[i];
-               skb_shinfo(to)->frags[j].size = min_t(int, skb_shinfo(to)->frags[j].size, len);
-               len -= skb_shinfo(to)->frags[j].size;
-               skb_frag_ref(to, j);
-               j++;
-       }
-       skb_shinfo(to)->nr_frags = j;
-}
-
 static int
 nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
                      bool csum_verify)
@@ -298,13 +253,13 @@ nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 }
 
 static struct sk_buff *
-nfqnl_build_packet_message(struct nfqnl_instance *queue,
+nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
                           struct nf_queue_entry *entry,
                           __be32 **packet_id_ptr)
 {
        size_t size;
        size_t data_len = 0, cap_len = 0;
-       int hlen = 0;
+       unsigned int hlen = 0;
        struct sk_buff *skb;
        struct nlattr *nla;
        struct nfqnl_msg_packet_hdr *pmsg;
@@ -356,14 +311,8 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
                if (data_len > entskb->len)
                        data_len = entskb->len;
 
-               if (!entskb->head_frag ||
-                   skb_headlen(entskb) < L1_CACHE_BYTES ||
-                   skb_shinfo(entskb)->nr_frags >= MAX_SKB_FRAGS)
-                       hlen = skb_headlen(entskb);
-
-               if (skb_has_frag_list(entskb))
-                       hlen = entskb->len;
-               hlen = min_t(int, data_len, hlen);
+               hlen = skb_zerocopy_headlen(entskb);
+               hlen = min_t(unsigned int, hlen, data_len);
                size += sizeof(struct nlattr) + hlen;
                cap_len = entskb->len;
                break;
@@ -372,7 +321,7 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
        if (queue->flags & NFQA_CFG_F_CONNTRACK)
                ct = nfqnl_ct_get(entskb, &size, &ctinfo);
 
-       skb = nfnetlink_alloc_skb(&init_net, size, queue->peer_portid,
+       skb = nfnetlink_alloc_skb(net, size, queue->peer_portid,
                                  GFP_ATOMIC);
        if (!skb)
                return NULL;
@@ -504,7 +453,7 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
                nla->nla_type = NFQA_PAYLOAD;
                nla->nla_len = nla_attr_size(data_len);
 
-               nfqnl_zcopy(skb, entskb, data_len, hlen);
+               skb_zerocopy(skb, entskb, data_len, hlen);
        }
 
        nlh->nlmsg_len = skb->len;
@@ -525,7 +474,7 @@ __nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
        __be32 *packet_id_ptr;
        int failopen = 0;
 
-       nskb = nfqnl_build_packet_message(queue, entry, &packet_id_ptr);
+       nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
        if (nskb == NULL) {
                err = -ENOMEM;
                goto err_out;