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-rw-r--r--net/core/skbuff.c121
1 files changed, 119 insertions, 2 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 32e31c299631..92116dfe827c 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3002,7 +3002,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb,
if (nskb->len == len + doffset)
goto perform_csum_check;
- if (!sg) {
+ if (!sg && !nskb->remcsum_offload) {
nskb->ip_summed = CHECKSUM_NONE;
nskb->csum = skb_copy_and_csum_bits(head_skb, offset,
skb_put(nskb, len),
@@ -3074,7 +3074,7 @@ skip_fraglist:
nskb->truesize += nskb->data_len;
perform_csum_check:
- if (!csum) {
+ if (!csum && !nskb->remcsum_offload) {
nskb->csum = skb_checksum(nskb, doffset,
nskb->len - doffset, 0);
nskb->ip_summed = CHECKSUM_NONE;
@@ -3088,6 +3088,16 @@ perform_csum_check:
* (see validate_xmit_skb_list() for example)
*/
segs->prev = tail;
+
+ /* Following permits correct backpressure, for protocols
+ * using skb_set_owner_w().
+ * Idea is to tranfert ownership from head_skb to last segment.
+ */
+ if (head_skb->destructor == sock_wfree) {
+ swap(tail->truesize, head_skb->truesize);
+ swap(tail->destructor, head_skb->destructor);
+ swap(tail->sk, head_skb->sk);
+ }
return segs;
err:
@@ -4130,6 +4140,113 @@ err_free:
}
EXPORT_SYMBOL(skb_vlan_untag);
+int skb_ensure_writable(struct sk_buff *skb, int write_len)
+{
+ if (!pskb_may_pull(skb, write_len))
+ return -ENOMEM;
+
+ if (!skb_cloned(skb) || skb_clone_writable(skb, write_len))
+ return 0;
+
+ return pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
+}
+EXPORT_SYMBOL(skb_ensure_writable);
+
+/* remove VLAN header from packet and update csum accordingly. */
+static int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci)
+{
+ struct vlan_hdr *vhdr;
+ unsigned int offset = skb->data - skb_mac_header(skb);
+ int err;
+
+ __skb_push(skb, offset);
+ err = skb_ensure_writable(skb, VLAN_ETH_HLEN);
+ if (unlikely(err))
+ goto pull;
+
+ skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);
+
+ vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
+ *vlan_tci = ntohs(vhdr->h_vlan_TCI);
+
+ memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
+ __skb_pull(skb, VLAN_HLEN);
+
+ vlan_set_encap_proto(skb, vhdr);
+ skb->mac_header += VLAN_HLEN;
+
+ if (skb_network_offset(skb) < ETH_HLEN)
+ skb_set_network_header(skb, ETH_HLEN);
+
+ skb_reset_mac_len(skb);
+pull:
+ __skb_pull(skb, offset);
+
+ return err;
+}
+
+int skb_vlan_pop(struct sk_buff *skb)
+{
+ u16 vlan_tci;
+ __be16 vlan_proto;
+ int err;
+
+ if (likely(vlan_tx_tag_present(skb))) {
+ skb->vlan_tci = 0;
+ } else {
+ if (unlikely((skb->protocol != htons(ETH_P_8021Q) &&
+ skb->protocol != htons(ETH_P_8021AD)) ||
+ skb->len < VLAN_ETH_HLEN))
+ return 0;
+
+ err = __skb_vlan_pop(skb, &vlan_tci);
+ if (err)
+ return err;
+ }
+ /* move next vlan tag to hw accel tag */
+ if (likely((skb->protocol != htons(ETH_P_8021Q) &&
+ skb->protocol != htons(ETH_P_8021AD)) ||
+ skb->len < VLAN_ETH_HLEN))
+ return 0;
+
+ vlan_proto = skb->protocol;
+ err = __skb_vlan_pop(skb, &vlan_tci);
+ if (unlikely(err))
+ return err;
+
+ __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
+ return 0;
+}
+EXPORT_SYMBOL(skb_vlan_pop);
+
+int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
+{
+ if (vlan_tx_tag_present(skb)) {
+ unsigned int offset = skb->data - skb_mac_header(skb);
+ int err;
+
+ /* __vlan_insert_tag expect skb->data pointing to mac header.
+ * So change skb->data before calling it and change back to
+ * original position later
+ */
+ __skb_push(skb, offset);
+ err = __vlan_insert_tag(skb, skb->vlan_proto,
+ vlan_tx_tag_get(skb));
+ if (err)
+ return err;
+ skb->protocol = skb->vlan_proto;
+ skb->mac_len += VLAN_HLEN;
+ __skb_pull(skb, offset);
+
+ if (skb->ip_summed == CHECKSUM_COMPLETE)
+ skb->csum = csum_add(skb->csum, csum_partial(skb->data
+ + (2 * ETH_ALEN), VLAN_HLEN, 0));
+ }
+ __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
+ return 0;
+}
+EXPORT_SYMBOL(skb_vlan_push);
+
/**
* alloc_skb_with_frags - allocate skb with page frags
*
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