linux-stable/include/linux/rtnetlink.h
Kuniyuki Iwashima d1c81818aa rtnetlink: Define rtnl_net_trylock().
We will need the per-netns version of rtnl_trylock().

rtnl_net_trylock() calls __rtnl_net_lock() only when rtnl_trylock()
successfully holds RTNL.

When RTNL is removed, we will use mutex_trylock() for per-netns RTNL.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29 11:54:57 +01:00

233 lines
7.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_RTNETLINK_H
#define __LINUX_RTNETLINK_H
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/wait.h>
#include <linux/refcount.h>
#include <uapi/linux/rtnetlink.h>
extern int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, u32 group, int echo);
static inline int rtnetlink_maybe_send(struct sk_buff *skb, struct net *net,
u32 pid, u32 group, int echo)
{
return !skb ? 0 : rtnetlink_send(skb, net, pid, group, echo);
}
extern int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid);
extern void rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid,
u32 group, const struct nlmsghdr *nlh, gfp_t flags);
extern void rtnl_set_sk_err(struct net *net, u32 group, int error);
extern int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics);
extern int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst,
u32 id, long expires, u32 error);
void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change, gfp_t flags,
u32 portid, const struct nlmsghdr *nlh);
void rtmsg_ifinfo_newnet(int type, struct net_device *dev, unsigned int change,
gfp_t flags, int *new_nsid, int new_ifindex);
struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev,
unsigned change, u32 event,
gfp_t flags, int *new_nsid,
int new_ifindex, u32 portid,
const struct nlmsghdr *nlh);
void rtmsg_ifinfo_send(struct sk_buff *skb, struct net_device *dev,
gfp_t flags, u32 portid, const struct nlmsghdr *nlh);
/* RTNL is used as a global lock for all changes to network configuration */
extern void rtnl_lock(void);
extern void rtnl_unlock(void);
extern int rtnl_trylock(void);
extern int rtnl_is_locked(void);
extern int rtnl_lock_killable(void);
extern bool refcount_dec_and_rtnl_lock(refcount_t *r);
extern wait_queue_head_t netdev_unregistering_wq;
extern atomic_t dev_unreg_count;
extern struct rw_semaphore pernet_ops_rwsem;
extern struct rw_semaphore net_rwsem;
#define ASSERT_RTNL() \
WARN_ONCE(!rtnl_is_locked(), \
"RTNL: assertion failed at %s (%d)\n", __FILE__, __LINE__)
#ifdef CONFIG_PROVE_LOCKING
extern bool lockdep_rtnl_is_held(void);
#else
static inline bool lockdep_rtnl_is_held(void)
{
return true;
}
#endif /* #ifdef CONFIG_PROVE_LOCKING */
/**
* rcu_dereference_rtnl - rcu_dereference with debug checking
* @p: The pointer to read, prior to dereferencing
*
* Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
* or RTNL. Note : Please prefer rtnl_dereference() or rcu_dereference()
*/
#define rcu_dereference_rtnl(p) \
rcu_dereference_check(p, lockdep_rtnl_is_held())
/**
* rtnl_dereference - fetch RCU pointer when updates are prevented by RTNL
* @p: The pointer to read, prior to dereferencing
*
* Return the value of the specified RCU-protected pointer, but omit
* the READ_ONCE(), because caller holds RTNL.
*/
#define rtnl_dereference(p) \
rcu_dereference_protected(p, lockdep_rtnl_is_held())
/**
* rcu_replace_pointer_rtnl - replace an RCU pointer under rtnl_lock, returning
* its old value
* @rp: RCU pointer, whose value is returned
* @p: regular pointer
*
* Perform a replacement under rtnl_lock, where @rp is an RCU-annotated
* pointer. The old value of @rp is returned, and @rp is set to @p
*/
#define rcu_replace_pointer_rtnl(rp, p) \
rcu_replace_pointer(rp, p, lockdep_rtnl_is_held())
#ifdef CONFIG_DEBUG_NET_SMALL_RTNL
void __rtnl_net_lock(struct net *net);
void __rtnl_net_unlock(struct net *net);
void rtnl_net_lock(struct net *net);
void rtnl_net_unlock(struct net *net);
int rtnl_net_trylock(struct net *net);
int rtnl_net_lock_cmp_fn(const struct lockdep_map *a, const struct lockdep_map *b);
bool rtnl_net_is_locked(struct net *net);
#define ASSERT_RTNL_NET(net) \
WARN_ONCE(!rtnl_net_is_locked(net), \
"RTNL_NET: assertion failed at %s (%d)\n", \
__FILE__, __LINE__)
bool lockdep_rtnl_net_is_held(struct net *net);
#define rcu_dereference_rtnl_net(net, p) \
rcu_dereference_check(p, lockdep_rtnl_net_is_held(net))
#define rtnl_net_dereference(net, p) \
rcu_dereference_protected(p, lockdep_rtnl_net_is_held(net))
#define rcu_replace_pointer_rtnl_net(net, rp, p) \
rcu_replace_pointer(rp, p, lockdep_rtnl_net_is_held(net))
#else
static inline void __rtnl_net_lock(struct net *net) {}
static inline void __rtnl_net_unlock(struct net *net) {}
static inline void rtnl_net_lock(struct net *net)
{
rtnl_lock();
}
static inline void rtnl_net_unlock(struct net *net)
{
rtnl_unlock();
}
static inline int rtnl_net_trylock(struct net *net)
{
return rtnl_trylock();
}
static inline void ASSERT_RTNL_NET(struct net *net)
{
ASSERT_RTNL();
}
#define rcu_dereference_rtnl_net(net, p) \
rcu_dereference_rtnl(p)
#define rtnl_net_dereference(net, p) \
rtnl_dereference(p)
#define rcu_replace_pointer_rtnl_net(net, rp, p) \
rcu_replace_pointer_rtnl(rp, p)
#endif
static inline struct netdev_queue *dev_ingress_queue(struct net_device *dev)
{
return rtnl_dereference(dev->ingress_queue);
}
static inline struct netdev_queue *dev_ingress_queue_rcu(struct net_device *dev)
{
return rcu_dereference(dev->ingress_queue);
}
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev);
#ifdef CONFIG_NET_INGRESS
void net_inc_ingress_queue(void);
void net_dec_ingress_queue(void);
#endif
#ifdef CONFIG_NET_EGRESS
void net_inc_egress_queue(void);
void net_dec_egress_queue(void);
void netdev_xmit_skip_txqueue(bool skip);
#endif
void rtnetlink_init(void);
void __rtnl_unlock(void);
void rtnl_kfree_skbs(struct sk_buff *head, struct sk_buff *tail);
extern int ndo_dflt_fdb_dump(struct sk_buff *skb,
struct netlink_callback *cb,
struct net_device *dev,
struct net_device *filter_dev,
int *idx);
extern int ndo_dflt_fdb_add(struct ndmsg *ndm,
struct nlattr *tb[],
struct net_device *dev,
const unsigned char *addr,
u16 vid,
u16 flags);
extern int ndo_dflt_fdb_del(struct ndmsg *ndm,
struct nlattr *tb[],
struct net_device *dev,
const unsigned char *addr,
u16 vid);
extern int ndo_dflt_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
struct net_device *dev, u16 mode,
u32 flags, u32 mask, int nlflags,
u32 filter_mask,
int (*vlan_fill)(struct sk_buff *skb,
struct net_device *dev,
u32 filter_mask));
extern void rtnl_offload_xstats_notify(struct net_device *dev);
static inline int rtnl_has_listeners(const struct net *net, u32 group)
{
struct sock *rtnl = net->rtnl;
return netlink_has_listeners(rtnl, group);
}
/**
* rtnl_notify_needed - check if notification is needed
* @net: Pointer to the net namespace
* @nlflags: netlink ingress message flags
* @group: rtnl group
*
* Based on the ingress message flags and rtnl group, returns true
* if a notification is needed, false otherwise.
*/
static inline bool
rtnl_notify_needed(const struct net *net, u16 nlflags, u32 group)
{
return (nlflags & NLM_F_ECHO) || rtnl_has_listeners(net, group);
}
void netdev_set_operstate(struct net_device *dev, int newstate);
#endif /* __LINUX_RTNETLINK_H */