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_assert_locked_ops_compat(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_assert_locked_ops_compat_or_invisible(const struct net_device *dev) 77 { 78 if (dev->reg_state == NETREG_REGISTERED || 79 dev->reg_state == NETREG_UNREGISTERING) 80 netdev_assert_locked_ops_compat(dev); 81 } 82 83 static inline void netdev_assert_locked_ops(const struct net_device *dev) 84 { 85 if (netdev_need_ops_lock(dev)) 86 netdev_assert_locked(dev); 87 } 88 89 static inline void netdev_lock_ops_compat(struct net_device *dev) 90 { 91 if (netdev_need_ops_lock(dev)) 92 netdev_lock(dev); 93 else 94 rtnl_lock(); 95 } 96 97 static inline void netdev_unlock_ops_compat(struct net_device *dev) 98 { 99 if (netdev_need_ops_lock(dev)) 100 netdev_unlock(dev); 101 else 102 rtnl_unlock(); 103 } 104 105 /* Matching "ops protected" category from netdevice.h */ 106 static inline int netdev_is_locked_ops_compat(const struct net_device *dev) 107 { 108 if (netdev_need_ops_lock(dev)) 109 return lockdep_is_held(&dev->lock); 110 return lockdep_rtnl_is_held(); 111 } 112 113 static inline int netdev_lock_cmp_fn(const struct lockdep_map *a, 114 const struct lockdep_map *b) 115 { 116 if (a == b) 117 return 0; 118 119 /* Allow locking multiple devices only under rtnl_lock, 120 * the exact order doesn't matter. 121 * Note that upper devices don't lock their ops, so nesting 122 * mostly happens in batched device removal for now. 123 */ 124 return lockdep_rtnl_is_held() ? -1 : 1; 125 } 126 127 #define netdev_lockdep_set_classes(dev) \ 128 { \ 129 static struct lock_class_key qdisc_tx_busylock_key; \ 130 static struct lock_class_key qdisc_xmit_lock_key; \ 131 static struct lock_class_key dev_addr_list_lock_key; \ 132 static struct lock_class_key dev_instance_lock_key; \ 133 unsigned int i; \ 134 \ 135 (dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key; \ 136 lockdep_set_class(&(dev)->addr_list_lock, \ 137 &dev_addr_list_lock_key); \ 138 lockdep_set_class(&(dev)->lock, \ 139 &dev_instance_lock_key); \ 140 lock_set_cmp_fn(&dev->lock, netdev_lock_cmp_fn, NULL); \ 141 for (i = 0; i < (dev)->num_tx_queues; i++) \ 142 lockdep_set_class(&(dev)->_tx[i]._xmit_lock, \ 143 &qdisc_xmit_lock_key); \ 144 } 145 146 #define netdev_lock_dereference(p, dev) \ 147 rcu_dereference_protected(p, lockdep_is_held(&(dev)->lock)) 148 149 #define netdev_ops_lock_dereference(p, dev) \ 150 rcu_dereference_protected(p, netdev_is_locked_ops_compat(dev)) 151 152 int netdev_debug_event(struct notifier_block *nb, unsigned long event, 153 void *ptr); 154 155 #endif 156