Commit 89f479f0 authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Alexei Starovoitov
Browse files

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: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarToshiaki Makita <toshiaki.makita1@gmail.com>
Acked-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/94ade9e853162ae1947941965193190da97457bc.1610475660.git.lorenzo@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 97a0e1ea

drivers/net/veth.c

+3 −15
Original line number Diff line number Diff line
@@ -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();

include/net/xdp.h

+2 −0
Original line number Diff line number Diff line
@@ -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)

net/core/xdp.c

+15 −0
Original line number Diff line number Diff line
@@ -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);