[PATCH v7 bpf-next 07/14] net: xdp: add multi-buff support to xdp_build_skb_from_fram
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: 2021-03-19 21:49:16
Also in:
bpf
Subsystem:
networking [general], the rest, xdp (express data path) · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Alexei Starovoitov, Daniel Borkmann, David S. Miller, Jesper Dangaard Brouer, John Fastabend
Introduce xdp multi-buff support to __xdp_build_skb_from_frame/xdp_build_skb_from_fram utility routines. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- net/core/xdp.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)
diff --git a/net/core/xdp.c b/net/core/xdp.c
index 430f516259d9..7388bc6d680b 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c@@ -603,9 +603,21 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf, struct sk_buff *skb, struct net_device *dev) { + skb_frag_t frag_list[MAX_SKB_FRAGS]; unsigned int headroom, frame_size; + int i, num_frags = 0; void *hard_start; + /* XDP multi-buff frame */ + if (unlikely(xdpf->mb)) { + struct xdp_shared_info *xdp_sinfo; + + xdp_sinfo = xdp_get_shared_info_from_frame(xdpf); + num_frags = xdp_sinfo->nr_frags; + memcpy(frag_list, xdp_sinfo->frags, + sizeof(skb_frag_t) * num_frags); + } + /* Part of headroom was reserved to xdpf */ headroom = sizeof(*xdpf) + xdpf->headroom;
@@ -624,6 +636,20 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf, if (xdpf->metasize) skb_metadata_set(skb, xdpf->metasize); + /* Single-buff XDP frame */ + if (likely(!num_frags)) + goto out; + + for (i = 0; i < num_frags; i++) { + struct page *page = xdp_get_frag_page(&frag_list[i]); + + skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, + page, xdp_get_frag_offset(&frag_list[i]), + xdp_get_frag_size(&frag_list[i]), + xdpf->frame_sz); + } + +out: /* Essential SKB info: protocol and skb->dev */ skb->protocol = eth_type_trans(skb, dev);
--
2.30.2