1 files changed, 81 insertions, 0 deletions

diff --git a/include/linux/ppp_channel.h b/include/linux/ppp_channel.h
new file mode 100644
index 000000000000..a942892d6dfe
--- /dev/null
+++ b/include/linux/ppp_channel.h
@@ -0,0 +1,81 @@
+#ifndef _PPP_CHANNEL_H_
+#define _PPP_CHANNEL_H_
+/*
+ * Definitions for the interface between the generic PPP code
+ * and a PPP channel.
+ *
+ * A PPP channel provides a way for the generic PPP code to send
+ * and receive packets over some sort of communications medium.
+ * Packets are stored in sk_buffs and have the 2-byte PPP protocol
+ * number at the start, but not the address and control bytes.
+ *
+ * Copyright 1999 Paul Mackerras.
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ * ==FILEVERSION 20000322==
+ */
+
+#include <linux/list.h>
+#include <linux/skbuff.h>
+#include <linux/poll.h>
+
+struct ppp_channel;
+
+struct ppp_channel_ops {
+        /* Send a packet (or multilink fragment) on this channel.
+           Returns 1 if it was accepted, 0 if not. */
+        int     (*start_xmit)(struct ppp_channel *, struct sk_buff *);
+        /* Handle an ioctl call that has come in via /dev/ppp. */
+        int     (*ioctl)(struct ppp_channel *, unsigned int, unsigned long);
+};
+
+struct ppp_channel {
+        void            *private;       /* channel private data */
+        struct ppp_channel_ops *ops;    /* operations for this channel */
+        int             mtu;            /* max transmit packet size */
+        int             hdrlen;         /* amount of headroom channel needs */
+        void            *ppp;           /* opaque to channel */
+        /* the following are not used at present */
+        int             speed;          /* transfer rate (bytes/second) */
+        int             latency;        /* overhead time in milliseconds */
+};
+
+#ifdef __KERNEL__
+/* Called by the channel when it can send some more data. */
+extern void ppp_output_wakeup(struct ppp_channel *);
+
+/* Called by the channel to process a received PPP packet.
+   The packet should have just the 2-byte PPP protocol header. */
+extern void ppp_input(struct ppp_channel *, struct sk_buff *);
+
+/* Called by the channel when an input error occurs, indicating
+   that we may have missed a packet. */
+extern void ppp_input_error(struct ppp_channel *, int code);
+
+/* Attach a channel to a given PPP unit. */
+extern int ppp_register_channel(struct ppp_channel *);
+
+/* Detach a channel from its PPP unit (e.g. on hangup). */
+extern void ppp_unregister_channel(struct ppp_channel *);
+
+/* Get the channel number for a channel */
+extern int ppp_channel_index(struct ppp_channel *);
+
+/* Get the unit number associated with a channel, or -1 if none */
+extern int ppp_unit_number(struct ppp_channel *);
+
+/*
+ * SMP locking notes:
+ * The channel code must ensure that when it calls ppp_unregister_channel,
+ * nothing is executing in any of the procedures above, for that
+ * channel.  The generic layer will ensure that nothing is executing
+ * in the start_xmit and ioctl routines for the channel by the time
+ * that ppp_unregister_channel returns.
+ */
+
+#endif /* __KERNEL__ */
+#endif