net, xdp: Introduce xdp_build_skb_from_frame utility routine
Introduce xdp_build_skb_from_frame utility routine to build the skb
from xdp_frame. Respect to __xdp_build_skb_from_frame,
xdp_build_skb_from_frame will allocate the skb object. Rely on
xdp_build_skb_from_frame in veth driver.
Introduce missing xdp metadata support in veth_xdp_rcv_one routine.
Add missing metadata support in veth_xdp_rcv_one().
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toshiaki Makita <toshiaki.makita1@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/94ade9e853162ae1947941965193190da97457bc.1610475660.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 99caae7..6e03b61 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -567,16 +567,10 @@ static struct sk_buff *veth_xdp_rcv_one(struct veth_rq *rq,
struct veth_xdp_tx_bq *bq,
struct veth_stats *stats)
{
- void *hard_start = frame->data - frame->headroom;
- int len = frame->len, delta = 0;
struct xdp_frame orig_frame;
struct bpf_prog *xdp_prog;
- unsigned int headroom;
struct sk_buff *skb;
- /* bpf_xdp_adjust_head() assures BPF cannot access xdp_frame area */
- hard_start -= sizeof(struct xdp_frame);
-
rcu_read_lock();
xdp_prog = rcu_dereference(rq->xdp_prog);
if (likely(xdp_prog)) {
@@ -590,8 +584,8 @@ static struct sk_buff *veth_xdp_rcv_one(struct veth_rq *rq,
switch (act) {
case XDP_PASS:
- delta = frame->data - xdp.data;
- len = xdp.data_end - xdp.data;
+ if (xdp_update_frame_from_buff(&xdp, frame))
+ goto err_xdp;
break;
case XDP_TX:
orig_frame = *frame;
@@ -629,18 +623,12 @@ static struct sk_buff *veth_xdp_rcv_one(struct veth_rq *rq,
}
rcu_read_unlock();
- headroom = sizeof(struct xdp_frame) + frame->headroom - delta;
- skb = veth_build_skb(hard_start, headroom, len, frame->frame_sz);
+ skb = xdp_build_skb_from_frame(frame, rq->dev);
if (!skb) {
xdp_return_frame(frame);
stats->rx_drops++;
- goto err;
}
- xdp_release_frame(frame);
- xdp_scrub_frame(frame);
- skb->protocol = eth_type_trans(skb, rq->dev);
-err:
return skb;
err_xdp:
rcu_read_unlock();
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 689206d..c4bfdc9 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -167,6 +167,8 @@ struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp);
struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
struct sk_buff *skb,
struct net_device *dev);
+struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+ struct net_device *dev);
static inline
void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp)
diff --git a/net/core/xdp.c b/net/core/xdp.c
index aeb09ed..0d2630a3 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -557,3 +557,18 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
return skb;
}
EXPORT_SYMBOL_GPL(__xdp_build_skb_from_frame);
+
+struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf,
+ struct net_device *dev)
+{
+ struct sk_buff *skb;
+
+ skb = kmem_cache_alloc(skbuff_head_cache, GFP_ATOMIC);
+ if (unlikely(!skb))
+ return NULL;
+
+ memset(skb, 0, offsetof(struct sk_buff, tail));
+
+ return __xdp_build_skb_from_frame(xdpf, skb, dev);
+}
+EXPORT_SYMBOL_GPL(xdp_build_skb_from_frame);