summaryrefslogtreecommitdiff
path: root/pfinet/linux-src/include/linux/notifier.h
diff options
context:
space:
mode:
authorRoland McGrath <roland@gnu.org>2000-02-04 03:21:18 +0000
committerRoland McGrath <roland@gnu.org>2000-02-04 03:21:18 +0000
commit9fd51e9b0ad33a89a83fdbbb66bd20d85f7893fb (patch)
tree8845b79f170028cb4380045c50277bbf075b5b7d /pfinet/linux-src/include/linux/notifier.h
Import of Linux 2.2.12 subset (ipv4 stack and related)
Diffstat (limited to 'pfinet/linux-src/include/linux/notifier.h')
-rw-r--r--pfinet/linux-src/include/linux/notifier.h115
1 files changed, 115 insertions, 0 deletions
diff --git a/pfinet/linux-src/include/linux/notifier.h b/pfinet/linux-src/include/linux/notifier.h
new file mode 100644
index 00000000..42faceaa
--- /dev/null
+++ b/pfinet/linux-src/include/linux/notifier.h
@@ -0,0 +1,115 @@
+/*
+ * Routines to manage notifier chains for passing status changes to any
+ * interested routines. We need this instead of hard coded call lists so
+ * that modules can poke their nose into the innards. The network devices
+ * needed them so here they are for the rest of you.
+ *
+ * Alan Cox <Alan.Cox@linux.org>
+ */
+
+#ifndef _LINUX_NOTIFIER_H
+#define _LINUX_NOTIFIER_H
+#include <linux/errno.h>
+
+struct notifier_block
+{
+ int (*notifier_call)(struct notifier_block *self, unsigned long, void *);
+ struct notifier_block *next;
+ int priority;
+};
+
+
+#ifdef __KERNEL__
+
+#define NOTIFY_DONE 0x0000 /* Don't care */
+#define NOTIFY_OK 0x0001 /* Suits me */
+#define NOTIFY_STOP_MASK 0x8000 /* Don't call further */
+#define NOTIFY_BAD (NOTIFY_STOP_MASK|0x0002) /* Bad/Veto action */
+
+extern __inline__ int notifier_chain_register(struct notifier_block **list, struct notifier_block *n)
+{
+ while(*list)
+ {
+ if(n->priority > (*list)->priority)
+ break;
+ list= &((*list)->next);
+ }
+ n->next = *list;
+ *list=n;
+ return 0;
+}
+
+/*
+ * Warning to any non GPL module writers out there.. these functions are
+ * GPL'd
+ */
+
+extern __inline__ int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n)
+{
+ while((*nl)!=NULL)
+ {
+ if((*nl)==n)
+ {
+ *nl=n->next;
+ return 0;
+ }
+ nl=&((*nl)->next);
+ }
+ return -ENOENT;
+}
+
+/*
+ * This is one of these things that is generally shorter inline
+ */
+
+extern __inline__ int notifier_call_chain(struct notifier_block **n, unsigned long val, void *v)
+{
+ int ret=NOTIFY_DONE;
+ struct notifier_block *nb = *n;
+ while(nb)
+ {
+ ret=nb->notifier_call(nb,val,v);
+ if(ret&NOTIFY_STOP_MASK)
+ return ret;
+ nb=nb->next;
+ }
+ return ret;
+}
+
+
+/*
+ * Declared notifiers so far. I can imagine quite a few more chains
+ * over time (eg laptop power reset chains, reboot chain (to clean
+ * device units up), device [un]mount chain, module load/unload chain,
+ * low memory chain, screenblank chain (for plug in modular screenblankers)
+ * VC switch chains (for loadable kernel svgalib VC switch helpers) etc...
+ */
+
+/* netdevice notifier chain */
+#define NETDEV_UP 0x0001 /* For now you can't veto a device up/down */
+#define NETDEV_DOWN 0x0002
+#define NETDEV_REBOOT 0x0003 /* Tell a protocol stack a network interface
+ detected a hardware crash and restarted
+ - we can use this eg to kick tcp sessions
+ once done */
+#define NETDEV_CHANGE 0x0004 /* Notify device state change */
+#define NETDEV_REGISTER 0x0005
+#define NETDEV_UNREGISTER 0x0006
+#define NETDEV_CHANGEMTU 0x0007
+#define NETDEV_CHANGEADDR 0x0008
+#define NETDEV_GOING_DOWN 0x0009
+#define NETDEV_CHANGENAME 0x000A
+
+#define SYS_DOWN 0x0001 /* Notify of system down */
+#define SYS_RESTART SYS_DOWN
+#define SYS_HALT 0x0002 /* Notify of system halt */
+#define SYS_POWER_OFF 0x0003 /* Notify of system power off */
+
+/*
+ * Publically visible notifier objects
+ */
+
+extern struct notifier_block *boot_notifier_list;
+
+#endif
+#endif