[PATCH] Modularize generic HDLC

This patch enables building of individual WAN protocol support
routines (parts of generic HDLC) as separate modules.
All protocol-private definitions are moved from hdlc.h file
to protocol drivers. User-space interface and interface
between generic HDLC and underlying low-level HDLC drivers
are unchanged.
Signed-off-by: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/wan/Kconfig

@@ -154,7 +154,7 @@ config HDLC
 	  If unsure, say N.
 
 config HDLC_RAW
-	bool "Raw HDLC support"
+	tristate "Raw HDLC support"
 	depends on HDLC
 	help
 	  Generic HDLC driver supporting raw HDLC over WAN connections.
@@ -162,7 +162,7 @@ config HDLC_RAW
 	  If unsure, say N.
 
 config HDLC_RAW_ETH
-	bool "Raw HDLC Ethernet device support"
+	tristate "Raw HDLC Ethernet device support"
 	depends on HDLC
 	help
 	  Generic HDLC driver supporting raw HDLC Ethernet device emulation
@@ -173,7 +173,7 @@ config HDLC_RAW_ETH
 	  If unsure, say N.
 
 config HDLC_CISCO
-	bool "Cisco HDLC support"
+	tristate "Cisco HDLC support"
 	depends on HDLC
 	help
 	  Generic HDLC driver supporting Cisco HDLC over WAN connections.
@@ -181,7 +181,7 @@ config HDLC_CISCO
 	  If unsure, say N.
 
 config HDLC_FR
-	bool "Frame Relay support"
+	tristate "Frame Relay support"
 	depends on HDLC
 	help
 	  Generic HDLC driver supporting Frame Relay over WAN connections.
@@ -189,7 +189,7 @@ config HDLC_FR
 	  If unsure, say N.
 
 config HDLC_PPP
-	bool "Synchronous Point-to-Point Protocol (PPP) support"
+	tristate "Synchronous Point-to-Point Protocol (PPP) support"
 	depends on HDLC
 	help
 	  Generic HDLC driver supporting PPP over WAN connections.
@@ -197,7 +197,7 @@ config HDLC_PPP
 	  If unsure, say N.
 
 config HDLC_X25
-	bool "X.25 protocol support"
+	tristate "X.25 protocol support"
 	depends on HDLC && (LAPB=m && HDLC=m || LAPB=y)
 	help
 	  Generic HDLC driver supporting X.25 over WAN connections.

drivers/net/wan/Makefile

@@ -9,14 +9,13 @@ cyclomx-y                       := cycx_main.o
 cyclomx-$(CONFIG_CYCLOMX_X25)	+= cycx_x25.o
 cyclomx-objs			:= $(cyclomx-y)  
 
-hdlc-y				:= hdlc_generic.o
-hdlc-$(CONFIG_HDLC_RAW)		+= hdlc_raw.o
-hdlc-$(CONFIG_HDLC_RAW_ETH)	+= hdlc_raw_eth.o
-hdlc-$(CONFIG_HDLC_CISCO)	+= hdlc_cisco.o
-hdlc-$(CONFIG_HDLC_FR)		+= hdlc_fr.o
-hdlc-$(CONFIG_HDLC_PPP)		+= hdlc_ppp.o
-hdlc-$(CONFIG_HDLC_X25)		+= hdlc_x25.o
-hdlc-objs			:= $(hdlc-y)
+obj-$(CONFIG_HDLC)		+= hdlc.o
+obj-$(CONFIG_HDLC_RAW)		+= hdlc_raw.o
+obj-$(CONFIG_HDLC_RAW_ETH)	+= hdlc_raw_eth.o
+obj-$(CONFIG_HDLC_CISCO)	+= hdlc_cisco.o
+obj-$(CONFIG_HDLC_FR)		+= hdlc_fr.o
+obj-$(CONFIG_HDLC_PPP)		+= hdlc_ppp.o	syncppp.o
+obj-$(CONFIG_HDLC_X25)		+= hdlc_x25.o
 
 pc300-y				:= pc300_drv.o
 pc300-$(CONFIG_PC300_MLPPP)	+= pc300_tty.o
@@ -38,10 +37,6 @@ obj-$(CONFIG_CYCLADES_SYNC)	+= cycx_drv.o cyclomx.o
 obj-$(CONFIG_LAPBETHER)		+= lapbether.o
 obj-$(CONFIG_SBNI)		+= sbni.o
 obj-$(CONFIG_PC300)		+= pc300.o
-obj-$(CONFIG_HDLC)		+= hdlc.o
-ifeq ($(CONFIG_HDLC_PPP),y)
-  obj-$(CONFIG_HDLC)		+= syncppp.o
-endif
 obj-$(CONFIG_N2)		+= n2.o
 obj-$(CONFIG_C101)		+= c101.o
 obj-$(CONFIG_WANXL)		+= wanxl.o

drivers/net/wan/hdlc_generic.c → drivers/net/wan/hdlc.c

 /*
  * Generic HDLC support routines for Linux
  *
- * Copyright (C) 1999 - 2005 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 1999 - 2006 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
@@ -17,9 +17,9 @@
  * Use sethdlc utility to set line parameters, protocol and PVCs
  *
  * How does it work:
- * - proto.open(), close(), start(), stop() calls are serialized.
+ * - proto->open(), close(), start(), stop() calls are serialized.
  *   The order is: open, [ start, stop ... ] close ...
- * - proto.start() and stop() are called with spin_lock_irq held.
+ * - proto->start() and stop() are called with spin_lock_irq held.
  */
 
 #include <linux/module.h>
@@ -38,10 +38,12 @@
 #include <linux/hdlc.h>
 
 
-static const char* version = "HDLC support module revision 1.19";
+static const char* version = "HDLC support module revision 1.20";
 
 #undef DEBUG_LINK
 
+static struct hdlc_proto *first_proto = NULL;
+
 
 static int hdlc_change_mtu(struct net_device *dev, int new_mtu)
 {
@@ -63,11 +65,11 @@ static struct net_device_stats *hdlc_get_stats(struct net_device *dev)
 static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev,
 		    struct packet_type *p, struct net_device *orig_dev)
 {
-	hdlc_device *hdlc = dev_to_hdlc(dev);
-	if (hdlc->proto.netif_rx)
-		return hdlc->proto.netif_rx(skb);
+	struct hdlc_device_desc *desc = dev_to_desc(dev);
+	if (desc->netif_rx)
+		return desc->netif_rx(skb);
 
-	hdlc->stats.rx_dropped++; /* Shouldn't happen */
+	desc->stats.rx_dropped++; /* Shouldn't happen */
 	dev_kfree_skb(skb);
 	return NET_RX_DROP;
 }
@@ -77,8 +79,8 @@ static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev,
 static inline void hdlc_proto_start(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
-	if (hdlc->proto.start)
-		return hdlc->proto.start(dev);
+	if (hdlc->proto->start)
+		return hdlc->proto->start(dev);
 }
 
 
@@ -86,8 +88,8 @@ static inline void hdlc_proto_start(struct net_device *dev)
 static inline void hdlc_proto_stop(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
-	if (hdlc->proto.stop)
-		return hdlc->proto.stop(dev);
+	if (hdlc->proto->stop)
+		return hdlc->proto->stop(dev);
 }
 
 
@@ -144,15 +146,15 @@ int hdlc_open(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 #ifdef DEBUG_LINK
-	printk(KERN_DEBUG "hdlc_open() carrier %i open %i\n",
+	printk(KERN_DEBUG "%s: hdlc_open() carrier %i open %i\n", dev->name,
 	       hdlc->carrier, hdlc->open);
 #endif
 
-	if (hdlc->proto.id == -1)
+	if (hdlc->proto == NULL)
 		return -ENOSYS;	/* no protocol attached */
 
-	if (hdlc->proto.open) {
-		int result = hdlc->proto.open(dev);
+	if (hdlc->proto->open) {
+		int result = hdlc->proto->open(dev);
 		if (result)
 			return result;
 	}
@@ -178,7 +180,7 @@ void hdlc_close(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 #ifdef DEBUG_LINK
-	printk(KERN_DEBUG "hdlc_close() carrier %i open %i\n",
+	printk(KERN_DEBUG "%s: hdlc_close() carrier %i open %i\n", dev->name,
 	       hdlc->carrier, hdlc->open);
 #endif
 
@@ -190,68 +192,34 @@ void hdlc_close(struct net_device *dev)
 
 	spin_unlock_irq(&hdlc->state_lock);
 
-	if (hdlc->proto.close)
-		hdlc->proto.close(dev);
+	if (hdlc->proto->close)
+		hdlc->proto->close(dev);
 }
 
 
 
-#ifndef CONFIG_HDLC_RAW
-#define hdlc_raw_ioctl(dev, ifr)	-ENOSYS
-#endif
-
-#ifndef CONFIG_HDLC_RAW_ETH
-#define hdlc_raw_eth_ioctl(dev, ifr)	-ENOSYS
-#endif
-
-#ifndef CONFIG_HDLC_PPP
-#define hdlc_ppp_ioctl(dev, ifr)	-ENOSYS
-#endif
-
-#ifndef CONFIG_HDLC_CISCO
-#define hdlc_cisco_ioctl(dev, ifr)	-ENOSYS
-#endif
-
-#ifndef CONFIG_HDLC_FR
-#define hdlc_fr_ioctl(dev, ifr)		-ENOSYS
-#endif
-
-#ifndef CONFIG_HDLC_X25
-#define hdlc_x25_ioctl(dev, ifr)	-ENOSYS
-#endif
-
-
 int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
-	hdlc_device *hdlc = dev_to_hdlc(dev);
-	unsigned int proto;
+	struct hdlc_proto *proto = first_proto;
+	int result;
 
 	if (cmd != SIOCWANDEV)
 		return -EINVAL;
 
-	switch(ifr->ifr_settings.type) {
-	case IF_PROTO_HDLC:
-	case IF_PROTO_HDLC_ETH:
-	case IF_PROTO_PPP:
-	case IF_PROTO_CISCO:
-	case IF_PROTO_FR:
-	case IF_PROTO_X25:
-		proto = ifr->ifr_settings.type;
-		break;
-
-	default:
-		proto = hdlc->proto.id;
+	if (dev_to_hdlc(dev)->proto) {
+		result = dev_to_hdlc(dev)->proto->ioctl(dev, ifr);
+		if (result != -EINVAL)
+			return result;
 	}
 
-	switch(proto) {
-	case IF_PROTO_HDLC:	return hdlc_raw_ioctl(dev, ifr);
-	case IF_PROTO_HDLC_ETH:	return hdlc_raw_eth_ioctl(dev, ifr);
-	case IF_PROTO_PPP:	return hdlc_ppp_ioctl(dev, ifr);
-	case IF_PROTO_CISCO:	return hdlc_cisco_ioctl(dev, ifr);
-	case IF_PROTO_FR:	return hdlc_fr_ioctl(dev, ifr);
-	case IF_PROTO_X25:	return hdlc_x25_ioctl(dev, ifr);
-	default:		return -EINVAL;
+	/* Not handled by currently attached protocol (if any) */
+
+	while (proto) {
+		if ((result = proto->ioctl(dev, ifr)) != -EINVAL)
+			return result;
+		proto = proto->next;
 	}
+	return -EINVAL;
 }
 
 void hdlc_setup(struct net_device *dev)
@@ -267,8 +235,6 @@ void hdlc_setup(struct net_device *dev)
 
 	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
 
-	hdlc->proto.id = -1;
-	hdlc->proto.detach = NULL;
 	hdlc->carrier = 1;
 	hdlc->open = 0;
 	spin_lock_init(&hdlc->state_lock);
@@ -277,7 +243,8 @@ void hdlc_setup(struct net_device *dev)
 struct net_device *alloc_hdlcdev(void *priv)
 {
 	struct net_device *dev;
-	dev = alloc_netdev(sizeof(hdlc_device), "hdlc%d", hdlc_setup);
+	dev = alloc_netdev(sizeof(struct hdlc_device_desc) +
+			   sizeof(hdlc_device), "hdlc%d", hdlc_setup);
 	if (dev)
 		dev_to_hdlc(dev)->priv = priv;
 	return dev;
@@ -286,13 +253,71 @@ struct net_device *alloc_hdlcdev(void *priv)
 void unregister_hdlc_device(struct net_device *dev)
 {
 	rtnl_lock();
-	hdlc_proto_detach(dev_to_hdlc(dev));
 	unregister_netdevice(dev);
+	detach_hdlc_protocol(dev);
 	rtnl_unlock();
 }
 
 
 
+int attach_hdlc_protocol(struct net_device *dev, struct hdlc_proto *proto,
+			 int (*rx)(struct sk_buff *skb), size_t size)
+{
+	detach_hdlc_protocol(dev);
+
+	if (!try_module_get(proto->module))
+		return -ENOSYS;
+
+	if (size)
+		if ((dev_to_hdlc(dev)->state = kmalloc(size,
+						       GFP_KERNEL)) == NULL) {
+			printk(KERN_WARNING "Memory squeeze on"
+			       " hdlc_proto_attach()\n");
+			module_put(proto->module);
+			return -ENOBUFS;
+		}
+	dev_to_hdlc(dev)->proto = proto;
+	dev_to_desc(dev)->netif_rx = rx;
+	return 0;
+}
+
+
+void detach_hdlc_protocol(struct net_device *dev)
+{
+	hdlc_device *hdlc = dev_to_hdlc(dev);
+
+	if (hdlc->proto) {
+		if (hdlc->proto->detach)
+			hdlc->proto->detach(dev);
+		module_put(hdlc->proto->module);
+		hdlc->proto = NULL;
+	}
+	kfree(hdlc->state);
+	hdlc->state = NULL;
+}
+
+
+void register_hdlc_protocol(struct hdlc_proto *proto)
+{
+	proto->next = first_proto;
+	first_proto = proto;
+}
+
+
+void unregister_hdlc_protocol(struct hdlc_proto *proto)
+{
+	struct hdlc_proto **p = &first_proto;
+	while (*p) {
+		if (*p == proto) {
+			*p = proto->next;
+			return;
+		}
+		p = &((*p)->next);
+	}
+}
+
+
+
 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
 MODULE_DESCRIPTION("HDLC support module");
 MODULE_LICENSE("GPL v2");
@@ -303,6 +328,10 @@ EXPORT_SYMBOL(hdlc_ioctl);
 EXPORT_SYMBOL(hdlc_setup);
 EXPORT_SYMBOL(alloc_hdlcdev);
 EXPORT_SYMBOL(unregister_hdlc_device);
+EXPORT_SYMBOL(register_hdlc_protocol);
+EXPORT_SYMBOL(unregister_hdlc_protocol);
+EXPORT_SYMBOL(attach_hdlc_protocol);
+EXPORT_SYMBOL(detach_hdlc_protocol);
 
 static struct packet_type hdlc_packet_type = {
 	.type = __constant_htons(ETH_P_HDLC),

drivers/net/wan/hdlc_ppp.c

@@ -2,7 +2,7 @@
  * Generic HDLC support routines for Linux
  * Point-to-point protocol support
  *
- * Copyright (C) 1999 - 2003 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 1999 - 2006 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
@@ -22,6 +22,21 @@
 #include <linux/lapb.h>
 #include <linux/rtnetlink.h>
 #include <linux/hdlc.h>
+#include <net/syncppp.h>
+
+struct ppp_state {
+	struct ppp_device pppdev;
+	struct ppp_device *syncppp_ptr;
+	int (*old_change_mtu)(struct net_device *dev, int new_mtu);
+};
+
+static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr);
+
+
+static inline struct ppp_state* state(hdlc_device *hdlc)
+{
+	return(struct ppp_state *)(hdlc->state);
+}
 
 
 static int ppp_open(struct net_device *dev)
@@ -30,16 +45,16 @@ static int ppp_open(struct net_device *dev)
 	void *old_ioctl;
 	int result;
 
-	dev->priv = &hdlc->state.ppp.syncppp_ptr;
-	hdlc->state.ppp.syncppp_ptr = &hdlc->state.ppp.pppdev;
-	hdlc->state.ppp.pppdev.dev = dev;
+	dev->priv = &state(hdlc)->syncppp_ptr;
+	state(hdlc)->syncppp_ptr = &state(hdlc)->pppdev;
+	state(hdlc)->pppdev.dev = dev;
 
 	old_ioctl = dev->do_ioctl;
-	hdlc->state.ppp.old_change_mtu = dev->change_mtu;
-	sppp_attach(&hdlc->state.ppp.pppdev);
+	state(hdlc)->old_change_mtu = dev->change_mtu;
+	sppp_attach(&state(hdlc)->pppdev);
 	/* sppp_attach nukes them. We don't need syncppp's ioctl */
 	dev->do_ioctl = old_ioctl;
-	hdlc->state.ppp.pppdev.sppp.pp_flags &= ~PP_CISCO;
+	state(hdlc)->pppdev.sppp.pp_flags &= ~PP_CISCO;
 	dev->type = ARPHRD_PPP;
 	result = sppp_open(dev);
 	if (result) {
@@ -59,7 +74,7 @@ static void ppp_close(struct net_device *dev)
 	sppp_close(dev);
 	sppp_detach(dev);
 	dev->rebuild_header = NULL;
-	dev->change_mtu = hdlc->state.ppp.old_change_mtu;
+	dev->change_mtu = state(hdlc)->old_change_mtu;
 	dev->mtu = HDLC_MAX_MTU;
 	dev->hard_header_len = 16;
 }
@@ -73,13 +88,24 @@ static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev)
 
 
 
-int hdlc_ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
+static struct hdlc_proto proto = {
+	.open		= ppp_open,
+	.close		= ppp_close,
+	.type_trans	= ppp_type_trans,
+	.ioctl		= ppp_ioctl,
+	.module		= THIS_MODULE,
+};
+
+
+static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 	int result;
 
 	switch (ifr->ifr_settings.type) {
 	case IF_GET_PROTO:
+		if (dev_to_hdlc(dev)->proto != &proto)
+			return -EINVAL;
 		ifr->ifr_settings.type = IF_PROTO_PPP;
 		return 0; /* return protocol only, no settable parameters */
 
@@ -96,13 +122,10 @@ int hdlc_ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
 		if (result)
 			return result;
 
-		hdlc_proto_detach(hdlc);
-		memset(&hdlc->proto, 0, sizeof(hdlc->proto));
-
-		hdlc->proto.open = ppp_open;
-		hdlc->proto.close = ppp_close;
-		hdlc->proto.type_trans = ppp_type_trans;
-		hdlc->proto.id = IF_PROTO_PPP;
+		result = attach_hdlc_protocol(dev, &proto, NULL,
+					      sizeof(struct ppp_state));
+		if (result)
+			return result;
 		dev->hard_start_xmit = hdlc->xmit;
 		dev->hard_header = NULL;
 		dev->type = ARPHRD_PPP;
@@ -113,3 +136,25 @@ int hdlc_ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 	return -EINVAL;
 }
+
+
+static int __init mod_init(void)
+{
+	register_hdlc_protocol(&proto);
+	return 0;
+}
+
+
+
+static void __exit mod_exit(void)
+{
+	unregister_hdlc_protocol(&proto);
+}
+
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
+MODULE_DESCRIPTION("PPP protocol support for generic HDLC");
+MODULE_LICENSE("GPL v2");

drivers/net/wan/hdlc_raw.c

@@ -2,7 +2,7 @@
  * Generic HDLC support routines for Linux
  * HDLC support
  *
- * Copyright (C) 1999 - 2003 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 1999 - 2006 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
@@ -24,6 +24,8 @@
 #include <linux/hdlc.h>
 
 
+static int raw_ioctl(struct net_device *dev, struct ifreq *ifr);
+
 static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)
 {
 	return __constant_htons(ETH_P_IP);
@@ -31,7 +33,14 @@ static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)
 
 
 
-int hdlc_raw_ioctl(struct net_device *dev, struct ifreq *ifr)
+static struct hdlc_proto proto = {
+	.type_trans	= raw_type_trans,
+	.ioctl		= raw_ioctl,
+	.module		= THIS_MODULE,
+};
+
+
+static int raw_ioctl(struct net_device *dev, struct ifreq *ifr)
 {
 	raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
 	const size_t size = sizeof(raw_hdlc_proto);
@@ -41,12 +50,14 @@ int hdlc_raw_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 	switch (ifr->ifr_settings.type) {
 	case IF_GET_PROTO:
+		if (dev_to_hdlc(dev)->proto != &proto)
+			return -EINVAL;
 		ifr->ifr_settings.type = IF_PROTO_HDLC;
 		if (ifr->ifr_settings.size < size) {
 			ifr->ifr_settings.size = size; /* data size wanted */
 			return -ENOBUFS;
 		}
-		if (copy_to_user(raw_s, &hdlc->state.raw_hdlc.settings, size))
+		if (copy_to_user(raw_s, hdlc->state, size))
 			return -EFAULT;
 		return 0;
 
@@ -71,12 +82,11 @@ int hdlc_raw_ioctl(struct net_device *dev, struct ifreq *ifr)
 		if (result)
 			return result;
 
-		hdlc_proto_detach(hdlc);
-		memcpy(&hdlc->state.raw_hdlc.settings, &new_settings, size);
-		memset(&hdlc->proto, 0, sizeof(hdlc->proto));
-
-		hdlc->proto.type_trans = raw_type_trans;
-		hdlc->proto.id = IF_PROTO_HDLC;
+		result = attach_hdlc_protocol(dev, &proto, NULL,
+					      sizeof(raw_hdlc_proto));
+		if (result)
+			return result;
+		memcpy(hdlc->state, &new_settings, size);
 		dev->hard_start_xmit = hdlc->xmit;
 		dev->hard_header = NULL;
 		dev->type = ARPHRD_RAWHDLC;
@@ -88,3 +98,25 @@ int hdlc_raw_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 	return -EINVAL;
 }
+
+
+static int __init mod_init(void)
+{
+	register_hdlc_protocol(&proto);
+	return 0;
+}
+
+
+
+static void __exit mod_exit(void)
+{
+	unregister_hdlc_protocol(&proto);
+}
+
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
+MODULE_DESCRIPTION("Raw HDLC protocol support for generic HDLC");
+MODULE_LICENSE("GPL v2");

drivers/net/wan/hdlc_raw_eth.c

@@ -2,7 +2,7 @@
  * Generic HDLC support routines for Linux
  * HDLC Ethernet emulation support
  *
- * Copyright (C) 2002-2003 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 2002-2006 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
@@ -25,6 +25,7 @@
 #include <linux/etherdevice.h>
 #include <linux/hdlc.h>
 
+static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr);
 
 static int eth_tx(struct sk_buff *skb, struct net_device *dev)
 {
@@ -44,7 +45,14 @@ static int eth_tx(struct sk_buff *skb, struct net_device *dev)
 }
 
 
-int hdlc_raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
+static struct hdlc_proto proto = {
+	.type_trans	= eth_type_trans,
+	.ioctl		= raw_eth_ioctl,
+	.module		= THIS_MODULE,
+};
+
+
+static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
 {
 	raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
 	const size_t size = sizeof(raw_hdlc_proto);
@@ -56,12 +64,14 @@ int hdlc_raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 	switch (ifr->ifr_settings.type) {
 	case IF_GET_PROTO:
+		if (dev_to_hdlc(dev)->proto != &proto)
+			return -EINVAL;
 		ifr->ifr_settings.type = IF_PROTO_HDLC_ETH;
 		if (ifr->ifr_settings.size < size) {
 			ifr->ifr_settings.size = size; /* data size wanted */
 			return -ENOBUFS;
 		}
-		if (copy_to_user(raw_s, &hdlc->state.raw_hdlc.settings, size))
+		if (copy_to_user(raw_s, hdlc->state, size))
 			return -EFAULT;
 		return 0;
 
@@ -86,12 +96,11 @@ int hdlc_raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
 		if (result)
 			return result;
 
-		hdlc_proto_detach(hdlc);
-		memcpy(&hdlc->state.raw_hdlc.settings, &new_settings, size);
-		memset(&hdlc->proto, 0, sizeof(hdlc->proto));
-
-		hdlc->proto.type_trans = eth_type_trans;
-		hdlc->proto.id = IF_PROTO_HDLC_ETH;
+		result = attach_hdlc_protocol(dev, &proto, NULL,
+					      sizeof(raw_hdlc_proto));
+		if (result)
+			return result;
+		memcpy(hdlc->state, &new_settings, size);
 		dev->hard_start_xmit = eth_tx;
 		old_ch_mtu = dev->change_mtu;
 		old_qlen = dev->tx_queue_len;
@@ -106,3 +115,25 @@ int hdlc_raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 	return -EINVAL;
 }
+
+
+static int __init mod_init(void)
+{
+	register_hdlc_protocol(&proto);
+	return 0;
+}
+
+
+
+static void __exit mod_exit(void)
+{
+	unregister_hdlc_protocol(&proto);
+}
+
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
+MODULE_DESCRIPTION("Ethernet encapsulation support for generic HDLC");
+MODULE_LICENSE("GPL v2");

drivers/net/wan/hdlc_x25.c

@@ -2,7 +2,7 @@
  * Generic HDLC support routines for Linux
  * X.25 support
  *
- * Copyright (C) 1999 - 2003 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 1999 - 2006 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
@@ -25,6 +25,8 @@
 
 #include <net/x25device.h>
 
+static int x25_ioctl(struct net_device *dev, struct ifreq *ifr);
+
 /* These functions are callbacks called by LAPB layer */
 
 static void x25_connect_disconnect(struct net_device *dev, int reason, int code)
@@ -162,30 +164,39 @@ static void x25_close(struct net_device *dev)
 
 static int x25_rx(struct sk_buff *skb)
 {
-	hdlc_device *hdlc = dev_to_hdlc(skb->dev);
+	struct hdlc_device_desc *desc = dev_to_desc(skb->dev);
 
 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
-		hdlc->stats.rx_dropped++;
+		desc->stats.rx_dropped++;
 		return NET_RX_DROP;
 	}
 
 	if (lapb_data_received(skb->dev, skb) == LAPB_OK)
 		return NET_RX_SUCCESS;
 
-	hdlc->stats.rx_errors++;
+	desc->stats.rx_errors++;
 	dev_kfree_skb_any(skb);
 	return NET_RX_DROP;
 }
 
 
+static struct hdlc_proto proto = {
+	.open		= x25_open,
+	.close		= x25_close,
+	.ioctl		= x25_ioctl,
+	.module		= THIS_MODULE,
+};
+
 
-int hdlc_x25_ioctl(struct net_device *dev, struct ifreq *ifr)
+static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 	int result;
 
 	switch (ifr->ifr_settings.type) {
 	case IF_GET_PROTO:
+		if (dev_to_hdlc(dev)->proto != &proto)
+			return -EINVAL;
 		ifr->ifr_settings.type = IF_PROTO_X25;
 		return 0; /* return protocol only, no settable parameters */
 
@@ -200,14 +211,9 @@ int hdlc_x25_ioctl(struct net_device *dev, struct ifreq *ifr)
 		if (result)
 			return result;
 
-		hdlc_proto_detach(hdlc);
-		memset(&hdlc->proto, 0, sizeof(hdlc->proto));
-
-		hdlc->proto.open = x25_open;
-		hdlc->proto.close = x25_close;
-		hdlc->proto.netif_rx = x25_rx;
-		hdlc->proto.type_trans = NULL;
-		hdlc->proto.id = IF_PROTO_X25;
+		if ((result = attach_hdlc_protocol(dev, &proto,
+						   x25_rx, 0)) != 0)
+			return result;
 		dev->hard_start_xmit = x25_xmit;
 		dev->hard_header = NULL;
 		dev->type = ARPHRD_X25;
@@ -218,3 +224,25 @@ int hdlc_x25_ioctl(struct net_device *dev, struct ifreq *ifr)
 
 	return -EINVAL;
 }
+
+
+static int __init mod_init(void)
+{
+	register_hdlc_protocol(&proto);
+	return 0;
+}
+
+
+
+static void __exit mod_exit(void)
+{
+	unregister_hdlc_protocol(&proto);
+}
+
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
+MODULE_DESCRIPTION("X.25 protocol support for generic HDLC");
+MODULE_LICENSE("GPL v2");

include/linux/hdlc.h

@@ -11,95 +11,46 @@
 #ifndef __HDLC_H
 #define __HDLC_H
 
-#define GENERIC_HDLC_VERSION 4	/* For synchronization with sethdlc utility */
-
-#define CLOCK_DEFAULT   0	/* Default setting */
-#define CLOCK_EXT	1	/* External TX and RX clock - DTE */
-#define CLOCK_INT	2	/* Internal TX and RX clock - DCE */
-#define CLOCK_TXINT	3	/* Internal TX and external RX clock */
-#define CLOCK_TXFROMRX	4	/* TX clock derived from external RX clock */
-
-
-#define ENCODING_DEFAULT	0 /* Default setting */
-#define ENCODING_NRZ		1
-#define ENCODING_NRZI		2
-#define ENCODING_FM_MARK	3
-#define ENCODING_FM_SPACE	4
-#define ENCODING_MANCHESTER	5
-
-
-#define PARITY_DEFAULT		0 /* Default setting */
-#define PARITY_NONE		1 /* No parity */
-#define PARITY_CRC16_PR0	2 /* CRC16, initial value 0x0000 */
-#define PARITY_CRC16_PR1	3 /* CRC16, initial value 0xFFFF */
-#define PARITY_CRC16_PR0_CCITT	4 /* CRC16, initial 0x0000, ITU-T version */
-#define PARITY_CRC16_PR1_CCITT	5 /* CRC16, initial 0xFFFF, ITU-T version */
-#define PARITY_CRC32_PR0_CCITT	6 /* CRC32, initial value 0x00000000 */
-#define PARITY_CRC32_PR1_CCITT	7 /* CRC32, initial value 0xFFFFFFFF */
-
-#define LMI_DEFAULT		0 /* Default setting */
-#define LMI_NONE		1 /* No LMI, all PVCs are static */
-#define LMI_ANSI		2 /* ANSI Annex D */
-#define LMI_CCITT		3 /* ITU-T Annex A */
-#define LMI_CISCO		4 /* The "original" LMI, aka Gang of Four */
 
 #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 <net/syncppp.h>
 #include <linux/hdlc/ioctl.h>
 
 
-typedef struct {		/* Used in Cisco and PPP mode */
-	u8 address;
-	u8 control;
-	u16 protocol;
-}__attribute__ ((packed)) hdlc_header;
-
-
-
-typedef struct {
-	u32 type;		/* code */
-	u32 par1;
-	u32 par2;
-	u16 rel;		/* reliability */
-	u32 time;
-}__attribute__ ((packed)) cisco_packet;
-#define	CISCO_PACKET_LEN	18
-#define	CISCO_BIG_PACKET_LEN	20
-
-
-
-typedef struct pvc_device_struct {
-	struct net_device *master;
-	struct net_device *main;
-	struct net_device *ether; /* bridged Ethernet interface */
-	struct pvc_device_struct *next;	/* Sorted in ascending DLCI order */
-	int dlci;
-	int open_count;
-
-	struct {
-		unsigned int new: 1;
-		unsigned int active: 1;
-		unsigned int exist: 1;
-		unsigned int deleted: 1;
-		unsigned int fecn: 1;
-		unsigned int becn: 1;
-		unsigned int bandwidth;	/* Cisco LMI reporting only */
-	}state;
-}pvc_device;
-
-
-
-typedef struct hdlc_device_struct {
-	/* To be initialized by hardware driver */
+/* 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);
+	unsigned short (*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);
@@ -107,82 +58,18 @@ typedef struct hdlc_device_struct {
 	/* 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 */
-	struct {
-		int (*open)(struct net_device *dev);
-		void (*close)(struct net_device *dev);
-
-		/* if open & DCD */
-		void (*start)(struct net_device *dev);
-		/* if open & !DCD */
-		void (*stop)(struct net_device *dev);
-
-		void (*detach)(struct hdlc_device_struct *hdlc);
-		int (*netif_rx)(struct sk_buff *skb);
-		unsigned short (*type_trans)(struct sk_buff *skb,
-					     struct net_device *dev);
-		int id;		/* IF_PROTO_HDLC/CISCO/FR/etc. */
-	}proto;
-
+	const struct hdlc_proto *proto;
 	int carrier;
 	int open;
 	spinlock_t state_lock;
-
-	union {
-		struct {
-			fr_proto settings;
-			pvc_device *first_pvc;
-			int dce_pvc_count;
-
-			struct timer_list timer;
-			unsigned long last_poll;
-			int reliable;
-			int dce_changed;
-			int request;
-			int fullrep_sent;
-			u32 last_errors; /* last errors bit list */
-			u8 n391cnt;
-			u8 txseq; /* TX sequence number */
-			u8 rxseq; /* RX sequence number */
-		}fr;
-
-		struct {
-			cisco_proto settings;
-
-			struct timer_list timer;
-			unsigned long last_poll;
-			int up;
-			int request_sent;
-			u32 txseq; /* TX sequence number */
-			u32 rxseq; /* RX sequence number */
-		}cisco;
-
-		struct {
-			raw_hdlc_proto settings;
-		}raw_hdlc;
-
-		struct {
-			struct ppp_device pppdev;
-			struct ppp_device *syncppp_ptr;
-			int (*old_change_mtu)(struct net_device *dev,
-					      int new_mtu);
-		}ppp;
-	}state;
+	void *state;
 	void *priv;
 }hdlc_device;
 
 
 
-int hdlc_raw_ioctl(struct net_device *dev, struct ifreq *ifr);
-int hdlc_raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr);
-int hdlc_cisco_ioctl(struct net_device *dev, struct ifreq *ifr);
-int hdlc_ppp_ioctl(struct net_device *dev, struct ifreq *ifr);
-int hdlc_fr_ioctl(struct net_device *dev, struct ifreq *ifr);
-int hdlc_x25_ioctl(struct net_device *dev, struct ifreq *ifr);
-
-
-/* Exported from hdlc.o */
+/* 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);
@@ -191,17 +78,21 @@ int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
 #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__ hdlc_device* dev_to_hdlc(struct net_device *dev)
+
+static __inline__ struct hdlc_device_desc* dev_to_desc(struct net_device *dev)
 {
 	return netdev_priv(dev);
 }
 
-
-static __inline__ pvc_device* dev_to_pvc(struct net_device *dev)
+static __inline__ hdlc_device* dev_to_hdlc(struct net_device *dev)
 {
-	return (pvc_device*)dev->priv;
+	return netdev_priv(dev) + sizeof(struct hdlc_device_desc);
 }
 
 
@@ -225,18 +116,14 @@ 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 */
-static __inline__ void hdlc_proto_detach(hdlc_device *hdlc)
-{
-	if (hdlc->proto.detach)
-		hdlc->proto.detach(hdlc);
-	hdlc->proto.detach = NULL;
-}
-
+void detach_hdlc_protocol(struct net_device *dev);
 
 static __inline__ struct net_device_stats *hdlc_stats(struct net_device *dev)
 {
-	return &dev_to_hdlc(dev)->stats;
+	return &dev_to_desc(dev)->stats;
 }
 
 
@@ -248,8 +135,8 @@ static __inline__ __be16 hdlc_type_trans(struct sk_buff *skb,
 	skb->mac.raw  = skb->data;
 	skb->dev      = dev;
 
-	if (hdlc->proto.type_trans)
-		return hdlc->proto.type_trans(skb, dev);
+	if (hdlc->proto->type_trans)
+		return hdlc->proto->type_trans(skb, dev);
 	else
 		return htons(ETH_P_HDLC);
 }

include/linux/hdlc/ioctl.h

 #ifndef __HDLC_IOCTL_H__
 #define __HDLC_IOCTL_H__
 
+
+#define GENERIC_HDLC_VERSION 4	/* For synchronization with sethdlc utility */
+
+#define CLOCK_DEFAULT   0	/* Default setting */
+#define CLOCK_EXT	1	/* External TX and RX clock - DTE */
+#define CLOCK_INT	2	/* Internal TX and RX clock - DCE */
+#define CLOCK_TXINT	3	/* Internal TX and external RX clock */
+#define CLOCK_TXFROMRX	4	/* TX clock derived from external RX clock */
+
+
+#define ENCODING_DEFAULT	0 /* Default setting */
+#define ENCODING_NRZ		1
+#define ENCODING_NRZI		2
+#define ENCODING_FM_MARK	3
+#define ENCODING_FM_SPACE	4
+#define ENCODING_MANCHESTER	5
+
+
+#define PARITY_DEFAULT		0 /* Default setting */
+#define PARITY_NONE		1 /* No parity */
+#define PARITY_CRC16_PR0	2 /* CRC16, initial value 0x0000 */
+#define PARITY_CRC16_PR1	3 /* CRC16, initial value 0xFFFF */
+#define PARITY_CRC16_PR0_CCITT	4 /* CRC16, initial 0x0000, ITU-T version */
+#define PARITY_CRC16_PR1_CCITT	5 /* CRC16, initial 0xFFFF, ITU-T version */
+#define PARITY_CRC32_PR0_CCITT	6 /* CRC32, initial value 0x00000000 */
+#define PARITY_CRC32_PR1_CCITT	7 /* CRC32, initial value 0xFFFFFFFF */
+
+#define LMI_DEFAULT		0 /* Default setting */
+#define LMI_NONE		1 /* No LMI, all PVCs are static */
+#define LMI_ANSI		2 /* ANSI Annex D */
+#define LMI_CCITT		3 /* ITU-T Annex A */
+#define LMI_CISCO		4 /* The "original" LMI, aka Gang of Four */
+
 typedef struct { 
 	unsigned int clock_rate; /* bits per second */
 	unsigned int clock_type; /* internal, external, TX-internal etc. */