/* * Generic HDLC support routines for Linux * * Copyright (C) 1999-2005 Krzysztof Halasa <khc@pm.waw.pl> * * This program is free software; you can redistribute it and/or modify it * under the terms of version 2 of the GNU General Public License * as published by the Free Software Foundation. */ #ifndef __HDLC_H #define __HDLC_H #define HDLC_MAX_MTU 1500 /* Ethernet 1500 bytes */ #if 0 #define HDLC_MAX_MRU (HDLC_MAX_MTU + 10 + 14 + 4) /* for ETH+VLAN over FR */ #else #define HDLC_MAX_MRU 1600 /* as required for FR network */ #endif #ifdef __KERNEL__ #include <linux/skbuff.h> #include <linux/netdevice.h> #include <linux/hdlc/ioctl.h> /* Used by all network devices here, pointed to by netdev_priv(dev) */ struct hdlc_device_desc { int (*netif_rx)(struct sk_buff *skb); struct net_device_stats stats; }; /* This structure is a private property of HDLC protocols. Hardware drivers have no interest here */ struct hdlc_proto { int (*open)(struct net_device *dev); void (*close)(struct net_device *dev); void (*start)(struct net_device *dev); /* if open & DCD */ void (*stop)(struct net_device *dev); /* if open & !DCD */ void (*detach)(struct net_device *dev); int (*ioctl)(struct net_device *dev, struct ifreq *ifr); __be16 (*type_trans)(struct sk_buff *skb, struct net_device *dev); struct module *module; struct hdlc_proto *next; /* next protocol in the list */ }; typedef struct hdlc_device { /* used by HDLC layer to take control over HDLC device from hw driver*/ int (*attach)(struct net_device *dev, unsigned short encoding, unsigned short parity); /* hardware driver must handle this instead of dev->hard_start_xmit */ int (*xmit)(struct sk_buff *skb, struct net_device *dev); /* Things below are for HDLC layer internal use only */ const struct hdlc_proto *proto; int carrier; int open; spinlock_t state_lock; void *state; void *priv; }hdlc_device; /* Exported from hdlc module */ /* Called by hardware driver when a user requests HDLC service */ int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd); /* Must be used by hardware driver on module startup/exit */ #define register_hdlc_device(dev) register_netdev(dev) void unregister_hdlc_device(struct net_device *dev); void register_hdlc_protocol(struct hdlc_proto *proto); void unregister_hdlc_protocol(struct hdlc_proto *proto); struct net_device *alloc_hdlcdev(void *priv); static __inline__ struct hdlc_device_desc* dev_to_desc(struct net_device *dev) { return netdev_priv(dev); } static __inline__ hdlc_device* dev_to_hdlc(struct net_device *dev) { return netdev_priv(dev) + sizeof(struct hdlc_device_desc); } static __inline__ void debug_frame(const struct sk_buff *skb) { int i; for (i=0; i < skb->len; i++) { if (i == 100) { printk("...\n"); return; } printk(" %02X", skb->data[i]); } printk("\n"); } /* Must be called by hardware driver when HDLC device is being opened */ int hdlc_open(struct net_device *dev); /* Must be called by hardware driver when HDLC device is being closed */ void hdlc_close(struct net_device *dev); int attach_hdlc_protocol(struct net_device *dev, struct hdlc_proto *proto, int (*rx)(struct sk_buff *skb), size_t size); /* May be used by hardware driver to gain control over HDLC device */ void detach_hdlc_protocol(struct net_device *dev); static __inline__ struct net_device_stats *hdlc_stats(struct net_device *dev) { return &dev_to_desc(dev)->stats; } static __inline__ __be16 hdlc_type_trans(struct sk_buff *skb, struct net_device *dev) { hdlc_device *hdlc = dev_to_hdlc(dev); skb->dev = dev; skb_reset_mac_header(skb); if (hdlc->proto->type_trans) return hdlc->proto->type_trans(skb, dev); else return htons(ETH_P_HDLC); } #endif /* __KERNEL */ #endif /* __HDLC_H */