Lorenzo Bianconi <lorenzo@xxxxxxxxxx> writes:
Introduce __xdp_build_skb_from_frame and
xdp_build_skb_from_frame
utility routines to build the skb from xdp_frame.
Add xdp multi-buff support to cpumap
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
---
include/net/xdp.h | 5 ++++
kernel/bpf/cpumap.c | 45 +---------------------------
net/core/xdp.c | 73
+++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 79 insertions(+), 44 deletions(-)
[...]
diff --git a/net/core/xdp.c b/net/core/xdp.c
index 6c8e743ad03a..55f3e9c69427 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -597,3 +597,76 @@ 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 = sizeof(*xdpf) + xdpf->headroom;
+ void *hard_start = xdpf->data - headroom;
+ skb_frag_t frag_list[MAX_SKB_FRAGS];
+ struct xdp_shared_info *xdp_sinfo;
+ int i, num_frags = 0;
+
+ xdp_sinfo = xdp_get_shared_info_from_frame(xdpf);
+ if (unlikely(xdpf->mb)) {
+ num_frags = xdp_sinfo->nr_frags;
+ memcpy(frag_list, xdp_sinfo->frags,
+ sizeof(skb_frag_t) * num_frags);
+ }
nit, can you please move the xdp_sinfo assignment inside this 'if'
? This would help to emphasize that regarding xdp_frame tailroom
as xdp_shared_info struct (rather than skb_shared_info) is correct
only when the mb bit is set
thanks,
Shay
+
+ skb = build_skb_around(skb, hard_start, xdpf->frame_sz);
+ if (unlikely(!skb))
+ return NULL;
[...]
