1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 3 #ifndef _NET_NETDEV_LOCK_H 4 #define _NET_NETDEV_LOCK_H 5 6 #include <linux/lockdep.h> 7 #include <linux/netdevice.h> 8 #include <linux/rtnetlink.h> 9 10 static inline bool netdev_trylock(struct net_device *dev) 11 { 12 return mutex_trylock(&dev->lock); 13 } 14 15 static inline void netdev_assert_locked(const struct net_device *dev) 16 { 17 lockdep_assert_held(&dev->lock); 18 } 19 20 static inline void 21 netdev_assert_locked_or_invisible(const struct net_device *dev) 22 { 23 if (dev->reg_state == NETREG_REGISTERED || 24 dev->reg_state == NETREG_UNREGISTERING) 25 netdev_assert_locked(dev); 26 } 27 28 static inline bool netdev_need_ops_lock(const struct net_device *dev) 29 { 30 bool ret = dev->request_ops_lock || !!dev->queue_mgmt_ops; 31 32 #if IS_ENABLED(CONFIG_NET_SHAPER) 33 ret |= !!dev->netdev_ops->net_shaper_ops; 34 #endif 35 36 return ret; 37 } 38 39 static inline void netdev_lock_ops(struct net_device *dev) 40 { 41 if (netdev_need_ops_lock(dev)) 42 netdev_lock(dev); 43 } 44 45 static inline void netdev_unlock_ops(struct net_device *dev) 46 { 47 if (netdev_need_ops_lock(dev)) 48 netdev_unlock(dev); 49 } 50 51 static inline void netdev_lock_ops_to_full(struct net_device *dev) 52 { 53 if (netdev_need_ops_lock(dev)) 54 netdev_assert_locked(dev); 55 else 56 netdev_lock(dev); 57 } 58 59 static inline void netdev_unlock_full_to_ops(struct net_device *dev) 60 { 61 if (netdev_need_ops_lock(dev)) 62 netdev_assert_locked(dev); 63 else 64 netdev_unlock(dev); 65 } 66 67 static inline void netdev_ops_assert_locked(const struct net_device *dev) 68 { 69 if (netdev_need_ops_lock(dev)) 70 lockdep_assert_held(&dev->lock); 71 else 72 ASSERT_RTNL(); 73 } 74 75 static inline void 76 netdev_ops_assert_locked_or_invisible(const struct net_device *dev) 77 { 78 if (dev->reg_state == NETREG_REGISTERED || 79 dev->reg_state == NETREG_UNREGISTERING) 80 netdev_ops_assert_locked(dev); 81 } 82 83 static inline void netdev_lock_ops_compat(struct net_device *dev) 84 { 85 if (netdev_need_ops_lock(dev)) 86 netdev_lock(dev); 87 else 88 rtnl_lock(); 89 } 90 91 static inline void netdev_unlock_ops_compat(struct net_device *dev) 92 { 93 if (netdev_need_ops_lock(dev)) 94 netdev_unlock(dev); 95 else 96 rtnl_unlock(); 97 } 98 99 static inline int netdev_lock_cmp_fn(const struct lockdep_map *a, 100 const struct lockdep_map *b) 101 { 102 if (a == b) 103 return 0; 104 105 /* Allow locking multiple devices only under rtnl_lock, 106 * the exact order doesn't matter. 107 * Note that upper devices don't lock their ops, so nesting 108 * mostly happens in batched device removal for now. 109 */ 110 return lockdep_rtnl_is_held() ? -1 : 1; 111 } 112 113 #define netdev_lockdep_set_classes(dev) \ 114 { \ 115 static struct lock_class_key qdisc_tx_busylock_key; \ 116 static struct lock_class_key qdisc_xmit_lock_key; \ 117 static struct lock_class_key dev_addr_list_lock_key; \ 118 static struct lock_class_key dev_instance_lock_key; \ 119 unsigned int i; \ 120 \ 121 (dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key; \ 122 lockdep_set_class(&(dev)->addr_list_lock, \ 123 &dev_addr_list_lock_key); \ 124 lockdep_set_class(&(dev)->lock, \ 125 &dev_instance_lock_key); \ 126 lock_set_cmp_fn(&dev->lock, netdev_lock_cmp_fn, NULL); \ 127 for (i = 0; i < (dev)->num_tx_queues; i++) \ 128 lockdep_set_class(&(dev)->_tx[i]._xmit_lock, \ 129 &qdisc_xmit_lock_key); \ 130 } 131 132 #define netdev_lock_dereference(p, dev) \ 133 rcu_dereference_protected(p, lockdep_is_held(&(dev)->lock)) 134 135 int netdev_debug_event(struct notifier_block *nb, unsigned long event, 136 void *ptr); 137 138 #endif 139