summaryrefslogtreecommitdiff
path: root/include/net/netdev_lock.h
blob: 9fb3e93857c3d38e7a6910b58dc2d334695f2654 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
/* SPDX-License-Identifier: GPL-2.0-or-later */

#ifndef _NET_NETDEV_LOCK_H
#define _NET_NETDEV_LOCK_H

#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>

static inline bool netdev_trylock(struct net_device *dev)
{
	return mutex_trylock(&dev->lock);
}

static inline void netdev_assert_locked(const struct net_device *dev)
{
	lockdep_assert_held(&dev->lock);
}

static inline void
netdev_assert_locked_or_invisible(const struct net_device *dev)
{
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING)
		netdev_assert_locked(dev);
}

static inline bool netdev_need_ops_lock(const struct net_device *dev)
{
	bool ret = dev->request_ops_lock || !!dev->queue_mgmt_ops;

#if IS_ENABLED(CONFIG_NET_SHAPER)
	ret |= !!dev->netdev_ops->net_shaper_ops;
#endif

	return ret;
}

static inline void netdev_lock_ops(struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_lock(dev);
}

static inline void netdev_unlock_ops(struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_unlock(dev);
}

static inline void netdev_lock_ops_to_full(struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_assert_locked(dev);
	else
		netdev_lock(dev);
}

static inline void netdev_unlock_full_to_ops(struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_assert_locked(dev);
	else
		netdev_unlock(dev);
}

static inline void netdev_assert_locked_ops_compat(const struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		lockdep_assert_held(&dev->lock);
	else
		ASSERT_RTNL();
}

static inline void
netdev_assert_locked_ops_compat_or_invisible(const struct net_device *dev)
{
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING)
		netdev_assert_locked_ops_compat(dev);
}

static inline void netdev_assert_locked_ops(const struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_assert_locked(dev);
}

static inline void netdev_lock_ops_compat(struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_lock(dev);
	else
		rtnl_lock();
}

static inline void netdev_unlock_ops_compat(struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		netdev_unlock(dev);
	else
		rtnl_unlock();
}

/* Matching "ops protected" category from netdevice.h */
static inline int netdev_is_locked_ops_compat(const struct net_device *dev)
{
	if (netdev_need_ops_lock(dev))
		return lockdep_is_held(&dev->lock);
	return lockdep_rtnl_is_held();
}

static inline int netdev_lock_cmp_fn(const struct lockdep_map *a,
				     const struct lockdep_map *b)
{
	if (a == b)
		return 0;

	/* Allow locking multiple devices only under rtnl_lock,
	 * the exact order doesn't matter.
	 * Note that upper devices don't lock their ops, so nesting
	 * mostly happens in batched device removal for now.
	 */
	return lockdep_rtnl_is_held() ? -1 : 1;
}

#define netdev_lockdep_set_classes(dev)				\
{								\
	static struct lock_class_key qdisc_tx_busylock_key;	\
	static struct lock_class_key qdisc_xmit_lock_key;	\
	static struct lock_class_key dev_addr_list_lock_key;	\
	static struct lock_class_key dev_instance_lock_key;	\
	unsigned int i;						\
								\
	(dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key;	\
	lockdep_set_class(&(dev)->addr_list_lock,		\
			  &dev_addr_list_lock_key);		\
	lockdep_set_class(&(dev)->lock,				\
			  &dev_instance_lock_key);		\
	lock_set_cmp_fn(&dev->lock, netdev_lock_cmp_fn, NULL);	\
	for (i = 0; i < (dev)->num_tx_queues; i++)		\
		lockdep_set_class(&(dev)->_tx[i]._xmit_lock,	\
				  &qdisc_xmit_lock_key);	\
}

#define netdev_lock_dereference(p, dev)				\
	rcu_dereference_protected(p, lockdep_is_held(&(dev)->lock))

#define netdev_ops_lock_dereference(p, dev)				\
	rcu_dereference_protected(p, netdev_is_locked_ops_compat(dev))

int netdev_debug_event(struct notifier_block *nb, unsigned long event,
		       void *ptr);

#endif