1 files changed, 96 insertions, 0 deletions
diff --git a/pfinet/linux/notifier.h b/pfinet/linux/notifier.h
new file mode 100644
index 00000000..78a44649
--- /dev/null
+++ b/pfinet/linux/notifier.h
@@ -0,0 +1,96 @@
+/*
+ *	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)(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(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 */
+#endif
+#endif