Files
linux/include/net/netdev_lock.h
Jakub Kicinski 1d3964e29e net: ethtool: cmis_cdb: hold instance lock for ops locked devices
FW module flashing was written so that the flashing happens
without holding rtnl_lock. This allows flashing multiple modules
at once. Current drivers can handle that well, but we should
let drivers depend on the netdev instance lock. Instance lock
is per netdev, and so is the module so we won't break parallel
updates.

Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260603012840.2254293-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-04 14:04:55 -07:00

145 lines
3.4 KiB
C

/* 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();
}
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))
int netdev_debug_event(struct notifier_block *nb, unsigned long event,
void *ptr);
#endif