diff options
| author | Lorenzo Bianconi <lorenzo@kernel.org> | 2021-01-12 19:26:12 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-01-20 14:10:35 -0800 |
| commit | 97a0e1ea7b41c2db762c1258632f6ccc22719510 (patch) | |
| tree | 9afe14e2d23751c32c32b57ce9ad8b8c2e2086d5 /net/core | |
| parent | 09c02d553c49fa6965fe39e28355b62f6ad02792 (diff) | |
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. Rely on __xdp_build_skb_from_frame in
cpumap code.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/4f9f4c6b3dd3933770c617eb6689dbc0c6e25863.1610475660.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/xdp.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/net/core/xdp.c b/net/core/xdp.c index 3a8c9ab4ecbe..aeb09ed0704c 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -513,3 +513,47 @@ void xdp_warn(const char *msg, const char *func, const int line) WARN(1, "XDP_WARN: %s(line:%d): %s\n", func, line, msg); }; EXPORT_SYMBOL_GPL(xdp_warn); + +struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf, + struct sk_buff *skb, + struct net_device *dev) +{ + unsigned int headroom, frame_size; + void *hard_start; + + /* Part of headroom was reserved to xdpf */ + headroom = sizeof(*xdpf) + xdpf->headroom; + + /* Memory size backing xdp_frame data already have reserved + * room for build_skb to place skb_shared_info in tailroom. + */ + frame_size = xdpf->frame_sz; + + hard_start = xdpf->data - headroom; + skb = build_skb_around(skb, hard_start, frame_size); + if (unlikely(!skb)) + return NULL; + + skb_reserve(skb, headroom); + __skb_put(skb, xdpf->len); + if (xdpf->metasize) + skb_metadata_set(skb, xdpf->metasize); + + /* Essential SKB info: protocol and skb->dev */ + skb->protocol = eth_type_trans(skb, dev); + + /* Optional SKB info, currently missing: + * - HW checksum info (skb->ip_summed) + * - HW RX hash (skb_set_hash) + * - RX ring dev queue index (skb_record_rx_queue) + */ + + /* Until page_pool get SKB return path, release DMA here */ + xdp_release_frame(xdpf); + + /* Allow SKB to reuse area used by xdp_frame */ + xdp_scrub_frame(xdpf); + + return skb; +} +EXPORT_SYMBOL_GPL(__xdp_build_skb_from_frame); |