[PATCH net-next v1 3/7] netdevsim: shared UDP tunnel port table support

[Jakub Kicinski]

Add the ability to simulate a device with a shared UDP tunnel port
table.

Try to reject the configurations and actions which are not supported
by the core, so we don't get syzcaller etc. warning reports.

Signed-off-by: Jakub Kicinski <k...@kernel.org>
---
 drivers/net/netdevsim/netdevsim.h   |  7 ++++++-
 drivers/net/netdevsim/udp_tunnels.c | 17 ++++++++++++++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/net/netdevsim/netdevsim.h 
b/drivers/net/netdevsim/netdevsim.h
index d164052e0393..4335ab4e5ce0 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -20,6 +20,7 @@
 #include <linux/netdevice.h>
 #include <linux/u64_stats_sync.h>
 #include <net/devlink.h>
+#include <net/udp_tunnel.h>
 #include <net/xdp.h>
 
 #define DRV_NAME       "netdevsim"
@@ -77,7 +78,8 @@ struct netdevsim {
        struct {
                u32 inject_error;
                u32 sleep;
-               u32 ports[2][NSIM_UDP_TUNNEL_N_PORTS];
+               u32 __ports[2][NSIM_UDP_TUNNEL_N_PORTS];
+               u32 (*ports)[NSIM_UDP_TUNNEL_N_PORTS];
                struct debugfs_u32_array dfs_ports[2];
        } udp_ports;
 };
@@ -197,9 +199,12 @@ struct nsim_dev {
        bool fail_trap_policer_set;
        bool fail_trap_policer_counter_get;
        struct {
+               struct udp_tunnel_nic_shared utn_shared;
+               u32 __ports[2][NSIM_UDP_TUNNEL_N_PORTS];
                bool sync_all;
                bool open_only;
                bool ipv4_only;
+               bool shared;
                u32 sleep;
        } udp_ports;
 };
diff --git a/drivers/net/netdevsim/udp_tunnels.c 
b/drivers/net/netdevsim/udp_tunnels.c
index ad65b860bd7b..6b98e6d1188f 100644
--- a/drivers/net/netdevsim/udp_tunnels.c
+++ b/drivers/net/netdevsim/udp_tunnels.c
@@ -112,7 +112,7 @@ nsim_udp_tunnels_info_reset_write(struct file *file, const 
char __user *data,
        struct net_device *dev = file->private_data;
        struct netdevsim *ns = netdev_priv(dev);
 
-       memset(&ns->udp_ports.ports, 0, sizeof(ns->udp_ports.ports));
+       memset(ns->udp_ports.ports, 0, sizeof(ns->udp_ports.__ports));
        rtnl_lock();
        udp_tunnel_nic_reset_ntf(dev);
        rtnl_unlock();
@@ -132,6 +132,17 @@ int nsim_udp_tunnels_info_create(struct nsim_dev *nsim_dev,
        struct netdevsim *ns = netdev_priv(dev);
        struct udp_tunnel_nic_info *info;
 
+       if (nsim_dev->udp_ports.shared && nsim_dev->udp_ports.open_only) {
+               dev_err(&nsim_dev->nsim_bus_dev->dev,
+                       "shared can't be used in conjunction with open_only\n");
+               return -EINVAL;
+       }
+
+       if (!nsim_dev->udp_ports.shared)
+               ns->udp_ports.ports = ns->udp_ports.__ports;
+       else
+               ns->udp_ports.ports = nsim_dev->udp_ports.__ports;
+
        debugfs_create_u32("udp_ports_inject_error", 0600,
                           ns->nsim_dev_port->ddir,
                           &ns->udp_ports.inject_error);
@@ -173,6 +184,8 @@ int nsim_udp_tunnels_info_create(struct nsim_dev *nsim_dev,
                info->flags |= UDP_TUNNEL_NIC_INFO_OPEN_ONLY;
        if (nsim_dev->udp_ports.ipv4_only)
                info->flags |= UDP_TUNNEL_NIC_INFO_IPV4_ONLY;
+       if (nsim_dev->udp_ports.shared)
+               info->shared = &nsim_dev->udp_ports.utn_shared;
 
        dev->udp_tunnel_nic_info = info;
        return 0;
@@ -192,6 +205,8 @@ void nsim_udp_tunnels_debugfs_create(struct nsim_dev 
*nsim_dev)
                            &nsim_dev->udp_ports.open_only);
        debugfs_create_bool("udp_ports_ipv4_only", 0600, nsim_dev->ddir,
                            &nsim_dev->udp_ports.ipv4_only);
+       debugfs_create_bool("udp_ports_shared", 0600, nsim_dev->ddir,
+                           &nsim_dev->udp_ports.shared);
        debugfs_create_u32("udp_ports_sleep", 0600, nsim_dev->ddir,
                           &nsim_dev->udp_ports.sleep);
 }
-- 
2.26.2