commit 02671e23e7b383763fe1ae4f20b56d8029f9dfc6
author Björn Töpel <bjorn.topel@intel.com> Wed May 02 13:01:30 2018 +0200
committer Alexei Starovoitov <ast@kernel.org> Thu May 03 15:55:24 2018 -0700
tree 1923fea58f6723654f8f8bff99ee4ec4838896b5
parent 1b1a251c83d29ec18b4a2191cce5c5b7117529ff

xsk: wire up XDP_SKB side of AF_XDP

This commit wires up the xskmap to XDP_SKB layer.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

net/core/dev.c

diff --git a/net/core/dev.c b/net/core/dev.c
index 8f8931b..aea36b5 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3994,12 +3994,12 @@ static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
 }
 
 static u32 netif_receive_generic_xdp(struct sk_buff *skb,
+				     struct xdp_buff *xdp,
 				     struct bpf_prog *xdp_prog)
 {
 	struct netdev_rx_queue *rxqueue;
 	void *orig_data, *orig_data_end;
 	u32 metalen, act = XDP_DROP;
-	struct xdp_buff xdp;
 	int hlen, off;
 	u32 mac_len;
 
@@ -4034,19 +4034,19 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 	 */
 	mac_len = skb->data - skb_mac_header(skb);
 	hlen = skb_headlen(skb) + mac_len;
-	xdp.data = skb->data - mac_len;
-	xdp.data_meta = xdp.data;
-	xdp.data_end = xdp.data + hlen;
-	xdp.data_hard_start = skb->data - skb_headroom(skb);
-	orig_data_end = xdp.data_end;
-	orig_data = xdp.data;
+	xdp->data = skb->data - mac_len;
+	xdp->data_meta = xdp->data;
+	xdp->data_end = xdp->data + hlen;
+	xdp->data_hard_start = skb->data - skb_headroom(skb);
+	orig_data_end = xdp->data_end;
+	orig_data = xdp->data;
 
 	rxqueue = netif_get_rxqueue(skb);
-	xdp.rxq = &rxqueue->xdp_rxq;
+	xdp->rxq = &rxqueue->xdp_rxq;
 
-	act = bpf_prog_run_xdp(xdp_prog, &xdp);
+	act = bpf_prog_run_xdp(xdp_prog, xdp);
 
-	off = xdp.data - orig_data;
+	off = xdp->data - orig_data;
 	if (off > 0)
 		__skb_pull(skb, off);
 	else if (off < 0)
@@ -4056,10 +4056,11 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 	/* check if bpf_xdp_adjust_tail was used. it can only "shrink"
 	 * pckt.
 	 */
-	off = orig_data_end - xdp.data_end;
+	off = orig_data_end - xdp->data_end;
 	if (off != 0) {
-		skb_set_tail_pointer(skb, xdp.data_end - xdp.data);
+		skb_set_tail_pointer(skb, xdp->data_end - xdp->data);
 		skb->len -= off;
+
 	}
 
 	switch (act) {
@@ -4068,7 +4069,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 		__skb_push(skb, mac_len);
 		break;
 	case XDP_PASS:
-		metalen = xdp.data - xdp.data_meta;
+		metalen = xdp->data - xdp->data_meta;
 		if (metalen)
 			skb_metadata_set(skb, metalen);
 		break;
@@ -4118,17 +4119,19 @@ static struct static_key generic_xdp_needed __read_mostly;
 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
 {
 	if (xdp_prog) {
-		u32 act = netif_receive_generic_xdp(skb, xdp_prog);
+		struct xdp_buff xdp;
+		u32 act;
 		int err;
 
+		act = netif_receive_generic_xdp(skb, &xdp, xdp_prog);
 		if (act != XDP_PASS) {
 			switch (act) {
 			case XDP_REDIRECT:
 				err = xdp_do_generic_redirect(skb->dev, skb,
-							      xdp_prog);
+							      &xdp, xdp_prog);
 				if (err)
 					goto out_redir;
-			/* fallthru to submit skb */
+				break;
 			case XDP_TX:
 				generic_xdp_tx(skb, xdp_prog);
 				break;