1 /* 2 * Routines to manage notifier chains for passing status changes to any 3 * interested routines. We need this instead of hard coded call lists so 4 * that modules can poke their nose into the innards. The network devices 5 * needed them so here they are for the rest of you. 6 * 7 * Alan Cox <[email protected]> 8 */ 9 10 #ifndef _LINUX_NOTIFIER_H 11 #define _LINUX_NOTIFIER_H 12 #include <linux/errno.h> 13 14 struct notifier_block 15 { 16 int (*notifier_call)(struct notifier_block *self, unsigned long, void *); 17 struct notifier_block *next; 18 int priority; 19 }; 20 21 22 #ifdef __KERNEL__ 23 24 extern int notifier_chain_register(struct notifier_block **list, struct notifier_block *n); 25 extern int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n); 26 extern int notifier_call_chain(struct notifier_block **n, unsigned long val, void *v); 27 28 #define NOTIFY_DONE 0x0000 /* Don't care */ 29 #define NOTIFY_OK 0x0001 /* Suits me */ 30 #define NOTIFY_STOP_MASK 0x8000 /* Don't call further */ 31 #define NOTIFY_BAD (NOTIFY_STOP_MASK|0x0002) /* Bad/Veto action */ 32 /* 33 * Clean way to return from the notifier and stop further calls. 34 */ 35 #define NOTIFY_STOP (NOTIFY_OK|NOTIFY_STOP_MASK) 36 37 /* 38 * Declared notifiers so far. I can imagine quite a few more chains 39 * over time (eg laptop power reset chains, reboot chain (to clean 40 * device units up), device [un]mount chain, module load/unload chain, 41 * low memory chain, screenblank chain (for plug in modular screenblankers) 42 * VC switch chains (for loadable kernel svgalib VC switch helpers) etc... 43 */ 44 45 /* netdevice notifier chain */ 46 #define NETDEV_UP 0x0001 /* For now you can't veto a device up/down */ 47 #define NETDEV_DOWN 0x0002 48 #define NETDEV_REBOOT 0x0003 /* Tell a protocol stack a network interface 49 detected a hardware crash and restarted 50 - we can use this eg to kick tcp sessions 51 once done */ 52 #define NETDEV_CHANGE 0x0004 /* Notify device state change */ 53 #define NETDEV_REGISTER 0x0005 54 #define NETDEV_UNREGISTER 0x0006 55 #define NETDEV_CHANGEMTU 0x0007 56 #define NETDEV_CHANGEADDR 0x0008 57 #define NETDEV_GOING_DOWN 0x0009 58 #define NETDEV_CHANGENAME 0x000A 59 #define NETDEV_FEAT_CHANGE 0x000B 60 61 #define SYS_DOWN 0x0001 /* Notify of system down */ 62 #define SYS_RESTART SYS_DOWN 63 #define SYS_HALT 0x0002 /* Notify of system halt */ 64 #define SYS_POWER_OFF 0x0003 /* Notify of system power off */ 65 66 #define NETLINK_URELEASE 0x0001 /* Unicast netlink socket released */ 67 68 #define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */ 69 #define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */ 70 #define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */ 71 #define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */ 72 #define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */ 73 #define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */ 74 75 #endif /* __KERNEL__ */ 76 #endif /* _LINUX_NOTIFIER_H */ 77