| 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 | |