include/linux/genetlink.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __LINUX_GENERIC_NETLINK_H
   3 #define __LINUX_GENERIC_NETLINK_H
   4
   5 #include <uapi/linux/genetlink.h>
   6
   7
   8 /* All generic netlink requests are serialized by a global lock.  */
   9 extern void genl_lock(void);
  10 extern void genl_unlock(void);
  11 #ifdef CONFIG_LOCKDEP
  12 extern bool lockdep_genl_is_held(void);
  13 #endif
  14
  15 /* for synchronisation between af_netlink and genetlink */
  16 extern atomic_t genl_sk_destructing_cnt;
  17 extern wait_queue_head_t genl_sk_destructing_waitq;
  18
  19 /**
  20  * rcu_dereference_genl - rcu_dereference with debug checking
  21  * @p: The pointer to read, prior to dereferencing
  22  *
  23  * Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
  24  * or genl mutex. Note : Please prefer genl_dereference() or rcu_dereference()
  25  */
  26 #define rcu_dereference_genl(p)                                 \
  27         rcu_dereference_check(p, lockdep_genl_is_held())
  28
  29 /**
  30  * genl_dereference - fetch RCU pointer when updates are prevented by genl mutex
  31  * @p: The pointer to read, prior to dereferencing
  32  *
  33  * Return the value of the specified RCU-protected pointer, but omit
  34  * both the smp_read_barrier_depends() and the READ_ONCE(), because
  35  * caller holds genl mutex.
  36  */
  37 #define genl_dereference(p)                                     \
  38         rcu_dereference_protected(p, lockdep_genl_is_held())
  39
  40 #define MODULE_ALIAS_GENL_FAMILY(family)\
  41  MODULE_ALIAS_NET_PF_PROTO_NAME(PF_NETLINK, NETLINK_GENERIC, "-family-" family)
  42
  43 #endif  /* __LINUX_GENERIC_NETLINK_H */