skbuff: allow 'slow_gro' for skb carring sock reference
This change leverages the infrastructure introduced by the previous
patches to allow soft devices passing to the GRO engine owned skbs
without impacting the fast-path.
It's up to the GRO caller ensuring the slow_gro bit validity before
invoking the GRO engine. The new helper skb_prepare_for_gro() is
introduced for that goal.
On slow_gro, skbs are aggregated only with equal sk.
Additionally, skb truesize on GRO recycle and free is correctly
updated so that sk wmem is not changed by the GRO processing.
rfc-> v1:
- fixed bad truesize on dev_gro_receive NAPI_FREE
- use the existing state bit
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index d04e286..fcbd977 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -958,6 +958,7 @@ void napi_skb_free_stolen_head(struct sk_buff *skb)
nf_reset_ct(skb);
skb_dst_drop(skb);
skb_ext_put(skb);
+ skb_orphan(skb);
skb->slow_gro = 0;
}
napi_skb_cache_put(skb);
@@ -3892,6 +3893,9 @@ int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb)
NAPI_GRO_CB(p)->last = skb;
NAPI_GRO_CB(p)->count++;
p->data_len += skb->len;
+
+ /* sk owenrship - if any - completely transferred to the aggregated packet */
+ skb->destructor = NULL;
p->truesize += skb->truesize;
p->len += skb->len;
@@ -4259,6 +4263,7 @@ int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb)
unsigned int headlen = skb_headlen(skb);
unsigned int len = skb_gro_len(skb);
unsigned int delta_truesize;
+ unsigned int new_truesize;
struct sk_buff *lp;
if (unlikely(p->len + len >= 65536 || NAPI_GRO_CB(skb)->flush))
@@ -4290,10 +4295,10 @@ int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb)
skb_frag_size_sub(frag, offset);
/* all fragments truesize : remove (head size + sk_buff) */
- delta_truesize = skb->truesize -
- SKB_TRUESIZE(skb_end_offset(skb));
+ new_truesize = SKB_TRUESIZE(skb_end_offset(skb));
+ delta_truesize = skb->truesize - new_truesize;
- skb->truesize -= skb->data_len;
+ skb->truesize = new_truesize;
skb->len -= skb->data_len;
skb->data_len = 0;
@@ -4322,12 +4327,16 @@ int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb)
memcpy(frag + 1, skbinfo->frags, sizeof(*frag) * skbinfo->nr_frags);
/* We dont need to clear skbinfo->nr_frags here */
- delta_truesize = skb->truesize - SKB_DATA_ALIGN(sizeof(struct sk_buff));
+ new_truesize = SKB_TRUESIZE(sizeof(struct sk_buff));
+ delta_truesize = skb->truesize - new_truesize;
+ skb->truesize = new_truesize;
NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE_STOLEN_HEAD;
goto done;
}
merge:
+ /* sk owenrship - if any - completely transferred to the aggregated packet */
+ skb->destructor = NULL;
delta_truesize = skb->truesize;
if (offset > headlen) {
unsigned int eat = offset - headlen;