net: convert some netlink netdev iterators to depend on the xarray

Reap the benefits of easier iteration thanks to the xarray.
Convert just the genetlink ones, those are easier to test.

Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20230726185530.2247698-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 26 insertions, 45 deletions

diff --git a/net/ethtool/tunnels.c b/net/ethtool/tunnels.c
index 67fb414ca859..05f752557b5e 100644
--- a/net/ethtool/tunnels.c
+++ b/net/ethtool/tunnels.c
@@ -212,8 +212,7 @@ err_unlock_rtnl:
 
 struct ethnl_tunnel_info_dump_ctx {
 	struct ethnl_req_info	req_info;
-	int			pos_hash;
-	int			pos_idx;
+	unsigned long		ifindex;
 };
 
 int ethnl_tunnel_info_start(struct netlink_callback *cb)
@@ -243,57 +242,39 @@ int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct ethnl_tunnel_info_dump_ctx *ctx = (void *)cb->ctx;
 	struct net *net = sock_net(skb->sk);
-	int s_idx = ctx->pos_idx;
-	int h, idx = 0;
+	struct net_device *dev;
 	int ret = 0;
 	void *ehdr;
 
 	rtnl_lock();
-	cb->seq = net->dev_base_seq;
-	for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
-		struct hlist_head *head;
-		struct net_device *dev;
-
-		head = &net->dev_index_head[h];
-		idx = 0;
-		hlist_for_each_entry(dev, head, index_hlist) {
-			if (idx < s_idx)
-				goto cont;
-
-			ehdr = ethnl_dump_put(skb, cb,
-					      ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY);
-			if (!ehdr) {
-				ret = -EMSGSIZE;
-				goto out;
-			}
-
-			ret = ethnl_fill_reply_header(skb, dev, ETHTOOL_A_TUNNEL_INFO_HEADER);
-			if (ret < 0) {
-				genlmsg_cancel(skb, ehdr);
-				goto out;
-			}
-
-			ctx->req_info.dev = dev;
-			ret = ethnl_tunnel_info_fill_reply(&ctx->req_info, skb);
-			ctx->req_info.dev = NULL;
-			if (ret < 0) {
-				genlmsg_cancel(skb, ehdr);
-				if (ret == -EOPNOTSUPP)
-					goto cont;
-				goto out;
-			}
-			genlmsg_end(skb, ehdr);
-cont:
-			idx++;
+	for_each_netdev_dump(net, dev, ctx->ifindex) {
+		ehdr = ethnl_dump_put(skb, cb,
+				      ETHTOOL_MSG_TUNNEL_INFO_GET_REPLY);
+		if (!ehdr) {
+			ret = -EMSGSIZE;
+			break;
 		}
+
+		ret = ethnl_fill_reply_header(skb, dev,
+					      ETHTOOL_A_TUNNEL_INFO_HEADER);
+		if (ret < 0) {
+			genlmsg_cancel(skb, ehdr);
+			break;
+		}
+
+		ctx->req_info.dev = dev;
+		ret = ethnl_tunnel_info_fill_reply(&ctx->req_info, skb);
+		ctx->req_info.dev = NULL;
+		if (ret < 0) {
+			genlmsg_cancel(skb, ehdr);
+			if (ret == -EOPNOTSUPP)
+				continue;
+			break;
+		}
+		genlmsg_end(skb, ehdr);
 	}
-out:
 	rtnl_unlock();
 
-	ctx->pos_hash = h;
-	ctx->pos_idx = idx;
-	nl_dump_check_consistent(cb, nlmsg_hdr(skb));
-
 	if (ret == -EMSGSIZE && skb->len)
 		return skb->len;
 	return ret;