Merge remote-tracking branch 'net-next/master' into mac80211-next

Resolve the merge conflict between Felix's/my and Toke's patches
coming into the tree through net and mac80211-next respectively.
Most of Felix's changes go away due to Toke's new infrastructure
work, my patch changes to "goto begin" (the label wasn't there
before) instead of returning NULL so flow control towards drivers
is preserved better.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 69 insertions, 34 deletions

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 1e329d411242..cbd19d250947 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3097,11 +3097,31 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb,
 	sg = !!(features & NETIF_F_SG);
 	csum = !!can_checksum_protocol(features, proto);
 
-	/* GSO partial only requires that we trim off any excess that
-	 * doesn't fit into an MSS sized block, so take care of that
-	 * now.
-	 */
-	if (sg && csum && (features & NETIF_F_GSO_PARTIAL)) {
+	if (sg && csum && (mss != GSO_BY_FRAGS))  {
+		if (!(features & NETIF_F_GSO_PARTIAL)) {
+			struct sk_buff *iter;
+
+			if (!list_skb ||
+			    !net_gso_ok(features, skb_shinfo(head_skb)->gso_type))
+				goto normal;
+
+			/* Split the buffer at the frag_list pointer.
+			 * This is based on the assumption that all
+			 * buffers in the chain excluding the last
+			 * containing the same amount of data.
+			 */
+			skb_walk_frags(head_skb, iter) {
+				if (skb_headlen(iter))
+					goto normal;
+
+				len -= iter->len;
+			}
+		}
+
+		/* GSO partial only requires that we trim off any excess that
+		 * doesn't fit into an MSS sized block, so take care of that
+		 * now.
+		 */
 		partial_segs = len / mss;
 		if (partial_segs > 1)
 			mss *= partial_segs;
@@ -3109,6 +3129,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb,
 			partial_segs = 0;
 	}
 
+normal:
 	headroom = skb_headroom(head_skb);
 	pos = skb_headlen(head_skb);
 
@@ -3300,21 +3321,29 @@ perform_csum_check:
 	 */
 	segs->prev = tail;
 
-	/* Update GSO info on first skb in partial sequence. */
 	if (partial_segs) {
+		struct sk_buff *iter;
 		int type = skb_shinfo(head_skb)->gso_type;
+		unsigned short gso_size = skb_shinfo(head_skb)->gso_size;
 
 		/* Update type to add partial and then remove dodgy if set */
-		type |= SKB_GSO_PARTIAL;
+		type |= (features & NETIF_F_GSO_PARTIAL) / NETIF_F_GSO_PARTIAL * SKB_GSO_PARTIAL;
 		type &= ~SKB_GSO_DODGY;
 
 		/* Update GSO info and prepare to start updating headers on
 		 * our way back down the stack of protocols.
 		 */
-		skb_shinfo(segs)->gso_size = skb_shinfo(head_skb)->gso_size;
-		skb_shinfo(segs)->gso_segs = partial_segs;
-		skb_shinfo(segs)->gso_type = type;
-		SKB_GSO_CB(segs)->data_offset = skb_headroom(segs) + doffset;
+		for (iter = segs; iter; iter = iter->next) {
+			skb_shinfo(iter)->gso_size = gso_size;
+			skb_shinfo(iter)->gso_segs = partial_segs;
+			skb_shinfo(iter)->gso_type = type;
+			SKB_GSO_CB(iter)->data_offset = skb_headroom(iter) + doffset;
+		}
+
+		if (tail->len - doffset <= gso_size)
+			skb_shinfo(tail)->gso_size = 0;
+		else if (tail != segs)
+			skb_shinfo(tail)->gso_segs = DIV_ROUND_UP(tail->len - doffset, gso_size);
 	}
 
 	/* Following permits correct backpressure, for protocols
@@ -4493,17 +4522,24 @@ int skb_ensure_writable(struct sk_buff *skb, int write_len)
 }
 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)
+/* remove VLAN header from packet and update csum accordingly.
+ * expects a non skb_vlan_tag_present skb with a vlan tag payload
+ */
+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 offset = skb->data - skb_mac_header(skb);
 	int err;
 
-	__skb_push(skb, offset);
+	if (WARN_ONCE(offset,
+		      "__skb_vlan_pop got skb with skb->data not at mac header (offset %d)\n",
+		      offset)) {
+		return -EINVAL;
+	}
+
 	err = skb_ensure_writable(skb, VLAN_ETH_HLEN);
 	if (unlikely(err))
-		goto pull;
+		return err;
 
 	skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);
 
@@ -4520,12 +4556,14 @@ static int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci)
 		skb_set_network_header(skb, ETH_HLEN);
 
 	skb_reset_mac_len(skb);
-pull:
-	__skb_pull(skb, offset);
 
 	return err;
 }
+EXPORT_SYMBOL(__skb_vlan_pop);
 
+/* Pop a vlan tag either from hwaccel or from payload.
+ * Expects skb->data at mac header.
+ */
 int skb_vlan_pop(struct sk_buff *skb)
 {
 	u16 vlan_tci;
@@ -4535,9 +4573,7 @@ int skb_vlan_pop(struct sk_buff *skb)
 	if (likely(skb_vlan_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))
+		if (unlikely(!eth_type_vlan(skb->protocol)))
 			return 0;
 
 		err = __skb_vlan_pop(skb, &vlan_tci);
@@ -4545,9 +4581,7 @@ int skb_vlan_pop(struct sk_buff *skb)
 			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))
+	if (likely(!eth_type_vlan(skb->protocol)))
 		return 0;
 
 	vlan_proto = skb->protocol;
@@ -4560,29 +4594,30 @@ int skb_vlan_pop(struct sk_buff *skb)
 }
 EXPORT_SYMBOL(skb_vlan_pop);
 
+/* Push a vlan tag either into hwaccel or into payload (if hwaccel tag present).
+ * Expects skb->data at mac header.
+ */
 int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
 {
 	if (skb_vlan_tag_present(skb)) {
-		unsigned int offset = skb->data - skb_mac_header(skb);
+		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);
+		if (WARN_ONCE(offset,
+			      "skb_vlan_push got skb with skb->data not at mac header (offset %d)\n",
+			      offset)) {
+			return -EINVAL;
+		}
+
 		err = __vlan_insert_tag(skb, skb->vlan_proto,
 					skb_vlan_tag_get(skb));
-		if (err) {
-			__skb_pull(skb, offset);
+		if (err)
 			return err;
-		}
 
 		skb->protocol = skb->vlan_proto;
 		skb->mac_len += VLAN_HLEN;
 
 		skb_postpush_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);
-		__skb_pull(skb, offset);
 	}
 	__vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
 	return 0;