1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * include/net/dsa_stubs.h - Stubs for the Distributed Switch Architecture framework 4 */ 5 6 #include <linux/mutex.h> 7 #include <linux/netdevice.h> 8 #include <linux/net_tstamp.h> 9 #include <net/dsa.h> 10 11 #if IS_ENABLED(CONFIG_NET_DSA) 12 13 extern const struct dsa_stubs *dsa_stubs; 14 15 struct dsa_stubs { 16 int (*conduit_hwtstamp_validate)(struct net_device *dev, 17 const struct kernel_hwtstamp_config *config, 18 struct netlink_ext_ack *extack); 19 }; 20 21 static inline int dsa_conduit_hwtstamp_validate(struct net_device *dev, 22 const struct kernel_hwtstamp_config *config, 23 struct netlink_ext_ack *extack) 24 { 25 if (!netdev_uses_dsa(dev)) 26 return 0; 27 28 /* rtnl_lock() is a sufficient guarantee, because as long as 29 * netdev_uses_dsa() returns true, the dsa_core module is still 30 * registered, and so, dsa_unregister_stubs() couldn't have run. 31 * For netdev_uses_dsa() to start returning false, it would imply that 32 * dsa_conduit_teardown() has executed, which requires rtnl_lock(). 33 */ 34 ASSERT_RTNL(); 35 36 return dsa_stubs->conduit_hwtstamp_validate(dev, config, extack); 37 } 38 39 #else 40 41 static inline int dsa_conduit_hwtstamp_validate(struct net_device *dev, 42 const struct kernel_hwtstamp_config *config, 43 struct netlink_ext_ack *extack) 44 { 45 return 0; 46 } 47 48 #endif 49