netdevsim: bpf: support fake map offload

Add to netdevsim ability to pretend it's offloading BPF maps.
We only allow allocation of tiny 2 entry maps, to keep things
simple.  Mutex lock may seem heavy for the operations we
perform, but we want to make sure callbacks can sleep.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 32270de..b803612 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -61,6 +61,9 @@ struct netdevsim {
 	bool bpf_tc_non_bound_accept;
 	bool bpf_xdpdrv_accept;
 	bool bpf_xdpoffload_accept;
+
+	bool bpf_map_accept;
+	struct list_head bpf_bound_maps;
 };
 
 extern struct dentry *nsim_ddir;