[PATCH v5 bpf-next 01/11] net: Refactor convert_to_xdp_frame

[David Ahern]

From: David Ahern <dah...@digitalocean.com>

Move the guts of convert_to_xdp_frame to a new helper, update_xdp_frame
so it can be reused in a later patch.

Suggested-by: Jesper Dangaard Brouer <bro...@redhat.com>
Signed-off-by: David Ahern <dah...@digitalocean.com>
Acked-by: Jesper Dangaard Brouer <bro...@redhat.com>
Acked-by: John Fastabend <john.fastab...@gmail.com>
---
 include/net/xdp.h | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/include/net/xdp.h b/include/net/xdp.h
index 3cc6d5d84aa4..3264fa882de3 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -93,32 +93,42 @@ static inline void xdp_scrub_frame(struct xdp_frame *frame)
 
 struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp);
 
-/* Convert xdp_buff to xdp_frame */
 static inline
-struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp)
+bool update_xdp_frame(struct xdp_buff *xdp, struct xdp_frame *xdp_frame)
 {
-       struct xdp_frame *xdp_frame;
        int metasize;
        int headroom;
 
-       if (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY)
-               return xdp_convert_zc_to_xdp_frame(xdp);
-
        /* 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;
+               return false;
 
        xdp_frame->data = xdp->data;
        xdp_frame->len  = xdp->data_end - xdp->data;
        xdp_frame->headroom = headroom - sizeof(*xdp_frame);
        xdp_frame->metasize = metasize;
 
+       return true;
+}
+
+/* Convert xdp_buff to xdp_frame */
+static inline
+struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp)
+{
+       struct xdp_frame *xdp_frame;
+
+       if (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY)
+               return xdp_convert_zc_to_xdp_frame(xdp);
+
+       /* Store info in top of packet */
+       xdp_frame = xdp->data_hard_start;
+
+       if (unlikely(!update_xdp_frame(xdp, xdp_frame)))
+               return NULL;
+
        /* rxq only valid until napi_schedule ends, convert to xdp_mem_info */
        xdp_frame->mem = xdp->rxq->mem;
 
-- 
2.21.1 (Apple Git-122.3)