From c0048cff8abb69c956ce1277d17a3f7a14e41522 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Tue, 17 Apr 2018 16:45:42 +0200 Subject: xdp: introduce a new xdp_frame type This is needed to convert drivers tuntap and virtio_net. This is a generalization of what is done inside cpumap, which will be converted later. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- include/net/xdp.h | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) (limited to 'include') diff --git a/include/net/xdp.h b/include/net/xdp.h index 15f8ade008b5..756c42811e78 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -58,6 +58,46 @@ struct xdp_buff { struct xdp_rxq_info *rxq; }; +struct xdp_frame { + void *data; + u16 len; + u16 headroom; + u16 metasize; + /* Lifetime of xdp_rxq_info is limited to NAPI/enqueue time, + * while mem info is valid on remote CPU. + */ + struct xdp_mem_info mem; +}; + +/* Convert xdp_buff to xdp_frame */ +static inline +struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp) +{ + struct xdp_frame *xdp_frame; + int metasize; + int headroom; + + /* Assure headroom is available for storing info */ + headroom = xdp->data - xdp->data_hard_start; + metasize = xdp->data - xdp->data_meta; + metasize = metasize > 0 ? metasize : 0; + if (unlikely((headroom - metasize) < sizeof(*xdp_frame))) + return NULL; + + /* Store info in top of packet */ + xdp_frame = xdp->data_hard_start; + + xdp_frame->data = xdp->data; + xdp_frame->len = xdp->data_end - xdp->data; + xdp_frame->headroom = headroom - sizeof(*xdp_frame); + xdp_frame->metasize = metasize; + + /* rxq only valid until napi_schedule ends, convert to xdp_mem_info */ + xdp_frame->mem = xdp->rxq->mem; + + return xdp_frame; +} + static inline void xdp_return_frame(void *data, struct xdp_mem_info *mem) { -- cgit v1.2.3