+static void mlx5e_udp_gso_prepare_last_skb(struct sk_buff *skb,
+ struct sk_buff *nskb,
+ int remaining)
+{
+ int bytes_needed = remaining, remaining_headlen,
remaining_page_offset;
+ int headlen = skb_transport_offset(skb) + sizeof(struct
udphdr);
+ int payload_len = remaining + sizeof(struct udphdr);
+ int k = 0, i, j;
+
+ skb_copy_bits(skb, 0, nskb->data, headlen);
+ nskb->dev = skb->dev;
+ skb_reset_mac_header(nskb);
+ skb_set_network_header(nskb, skb_network_offset(skb));
+ skb_set_transport_header(nskb, skb_transport_offset(skb));
+ skb_set_tail_pointer(nskb, headlen);
+
+ /* How many frags do we need? */
+ for (i = skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) {
+ bytes_needed -=
skb_frag_size(&skb_shinfo(skb)->frags[i]);
+ k++;
+ if (bytes_needed <= 0)
+ break;
+ }
+
+ /* Fill the first frag and split it if necessary */
+ j = skb_shinfo(skb)->nr_frags - k;
+ remaining_page_offset = -bytes_needed;
+ skb_fill_page_desc(nskb, 0,
+ skb_shinfo(skb)->frags[j].page.p,
+ skb_shinfo(skb)->frags[j].page_offset + remaining_page_offset,
+ skb_shinfo(skb)->frags[j].size -
remaining_page_offset);
+
+ skb_frag_ref(skb, j);
+
+ /* Fill the rest of the frags */
+ for (i = 1; i < k; i++) {
+ j = skb_shinfo(skb)->nr_frags - k + i;
+
+ skb_fill_page_desc(nskb, i,
+ skb_shinfo(skb)->frags[j].page.p,
+ skb_shinfo(skb)->frags[j].page_offset,
+ skb_shinfo(skb)->frags[j].size);
+ skb_frag_ref(skb, j);
+ }
+ skb_shinfo(nskb)->nr_frags = k;
+
+ remaining_headlen = remaining - skb->data_len;
+
+ /* headlen contains remaining data? */
+ if (remaining_headlen > 0)
+ skb_copy_bits(skb, skb->len - remaining, nskb->data
+ headlen,
+ remaining_headlen);
+ nskb->len = remaining + headlen;
+ nskb->data_len = payload_len - sizeof(struct udphdr) +
+ max_t(int, 0, remaining_headlen);
+ nskb->protocol = skb->protocol;
+ if (nskb->protocol == htons(ETH_P_IP)) {
+ ip_hdr(nskb)->id = htons(ntohs(ip_hdr(nskb)->id) +
+ skb_shinfo(skb)->gso_segs);
+ ip_hdr(nskb)->tot_len =
+ htons(payload_len + sizeof(struct iphdr));
+ } else {
+ ipv6_hdr(nskb)->payload_len = htons(payload_len);
+ }
+ udp_hdr(nskb)->len = htons(payload_len);
+ skb_shinfo(nskb)->gso_size = 0;
+ nskb->ip_summed = skb->ip_summed;
+ nskb->csum_start = skb->csum_start;
+ nskb->csum_offset = skb->csum_offset;
+ nskb->queue_mapping = skb->queue_mapping;
+}
+
+/* might send skbs and update wqe and pi */
+struct sk_buff *mlx5e_udp_gso_handle_tx_skb(struct net_device *netdev,
+ struct mlx5e_txqsq *sq,
+ struct sk_buff *skb,
+ struct mlx5e_tx_wqe **wqe,
+ u16 *pi)
+{
+ int payload_len = skb_shinfo(skb)->gso_size + sizeof(struct
udphdr);
+ int headlen = skb_transport_offset(skb) + sizeof(struct
udphdr);
+ int remaining = (skb->len - headlen) %
skb_shinfo(skb)->gso_size;
+ struct sk_buff *nskb;
+
+ if (skb->protocol == htons(ETH_P_IP))
+ ip_hdr(skb)->tot_len = htons(payload_len +
sizeof(struct iphdr));
+ else
+ ipv6_hdr(skb)->payload_len = htons(payload_len);
+ udp_hdr(skb)->len = htons(payload_len);
+ if (!remaining)
+ return skb;
+
+ nskb = alloc_skb(max_t(int, headlen, headlen + remaining -
skb->data_len), GFP_ATOMIC);
+ if (unlikely(!nskb)) {
+ sq->stats->dropped++;
+ return NULL;
+ }
+
+ mlx5e_udp_gso_prepare_last_skb(skb, nskb, remaining);
+
+ skb_shinfo(skb)->gso_segs--;
+ pskb_trim(skb, skb->len - remaining);
+ mlx5e_sq_xmit(sq, skb, *wqe, *pi);
+ mlx5e_sq_fetch_wqe(sq, wqe, pi);
+ return nskb;
+}
