[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>
diff --git a/drivers/net/wan/hdlc_cisco.c b/drivers/net/wan/hdlc_cisco.c
index f289dab..7ec2b2f 100644
--- a/drivers/net/wan/hdlc_cisco.c
+++ b/drivers/net/wan/hdlc_cisco.c
@@ -2,7 +2,7 @@
* Generic HDLC support routines for Linux
* Cisco HDLC support
*
- * Copyright (C) 2000 - 2003 Krzysztof Halasa <khc@pm.waw.pl>
+ * Copyright (C) 2000 - 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
@@ -34,17 +34,56 @@
#define CISCO_KEEPALIVE_REQ 2 /* Cisco keepalive request */
+struct hdlc_header {
+ u8 address;
+ u8 control;
+ u16 protocol;
+}__attribute__ ((packed));
+
+
+struct cisco_packet {
+ u32 type; /* code */
+ u32 par1;
+ u32 par2;
+ u16 rel; /* reliability */
+ u32 time;
+}__attribute__ ((packed));
+#define CISCO_PACKET_LEN 18
+#define CISCO_BIG_PACKET_LEN 20
+
+
+struct cisco_state {
+ 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 */
+};
+
+
+static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr);
+
+
+static inline struct cisco_state * state(hdlc_device *hdlc)
+{
+ return(struct cisco_state *)(hdlc->state);
+}
+
+
static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev,
u16 type, void *daddr, void *saddr,
unsigned int len)
{
- hdlc_header *data;
+ struct hdlc_header *data;
#ifdef DEBUG_HARD_HEADER
printk(KERN_DEBUG "%s: cisco_hard_header called\n", dev->name);
#endif
- skb_push(skb, sizeof(hdlc_header));
- data = (hdlc_header*)skb->data;
+ skb_push(skb, sizeof(struct hdlc_header));
+ data = (struct hdlc_header*)skb->data;
if (type == CISCO_KEEPALIVE)
data->address = CISCO_MULTICAST;
else
@@ -52,7 +91,7 @@
data->control = 0;
data->protocol = htons(type);
- return sizeof(hdlc_header);
+ return sizeof(struct hdlc_header);
}
@@ -61,9 +100,10 @@
u32 par1, u32 par2)
{
struct sk_buff *skb;
- cisco_packet *data;
+ struct cisco_packet *data;
- skb = dev_alloc_skb(sizeof(hdlc_header) + sizeof(cisco_packet));
+ skb = dev_alloc_skb(sizeof(struct hdlc_header) +
+ sizeof(struct cisco_packet));
if (!skb) {
printk(KERN_WARNING
"%s: Memory squeeze on cisco_keepalive_send()\n",
@@ -72,7 +112,7 @@
}
skb_reserve(skb, 4);
cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0);
- data = (cisco_packet*)(skb->data + 4);
+ data = (struct cisco_packet*)(skb->data + 4);
data->type = htonl(type);
data->par1 = htonl(par1);
@@ -81,7 +121,7 @@
/* we will need do_div here if 1000 % HZ != 0 */
data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ));
- skb_put(skb, sizeof(cisco_packet));
+ skb_put(skb, sizeof(struct cisco_packet));
skb->priority = TC_PRIO_CONTROL;
skb->dev = dev;
skb->nh.raw = skb->data;
@@ -93,9 +133,9 @@
static __be16 cisco_type_trans(struct sk_buff *skb, struct net_device *dev)
{
- hdlc_header *data = (hdlc_header*)skb->data;
+ struct hdlc_header *data = (struct hdlc_header*)skb->data;
- if (skb->len < sizeof(hdlc_header))
+ if (skb->len < sizeof(struct hdlc_header))
return __constant_htons(ETH_P_HDLC);
if (data->address != CISCO_MULTICAST &&
@@ -106,7 +146,7 @@
case __constant_htons(ETH_P_IP):
case __constant_htons(ETH_P_IPX):
case __constant_htons(ETH_P_IPV6):
- skb_pull(skb, sizeof(hdlc_header));
+ skb_pull(skb, sizeof(struct hdlc_header));
return data->protocol;
default:
return __constant_htons(ETH_P_HDLC);
@@ -118,12 +158,12 @@
{
struct net_device *dev = skb->dev;
hdlc_device *hdlc = dev_to_hdlc(dev);
- hdlc_header *data = (hdlc_header*)skb->data;
- cisco_packet *cisco_data;
+ struct hdlc_header *data = (struct hdlc_header*)skb->data;
+ struct cisco_packet *cisco_data;
struct in_device *in_dev;
u32 addr, mask;
- if (skb->len < sizeof(hdlc_header))
+ if (skb->len < sizeof(struct hdlc_header))
goto rx_error;
if (data->address != CISCO_MULTICAST &&
@@ -137,15 +177,17 @@
return NET_RX_SUCCESS;
case CISCO_KEEPALIVE:
- if (skb->len != sizeof(hdlc_header) + CISCO_PACKET_LEN &&
- skb->len != sizeof(hdlc_header) + CISCO_BIG_PACKET_LEN) {
- printk(KERN_INFO "%s: Invalid length of Cisco "
- "control packet (%d bytes)\n",
- dev->name, skb->len);
+ if ((skb->len != sizeof(struct hdlc_header) +
+ CISCO_PACKET_LEN) &&
+ (skb->len != sizeof(struct hdlc_header) +
+ CISCO_BIG_PACKET_LEN)) {
+ printk(KERN_INFO "%s: Invalid length of Cisco control"
+ " packet (%d bytes)\n", dev->name, skb->len);
goto rx_error;
}
- cisco_data = (cisco_packet*)(skb->data + sizeof(hdlc_header));
+ cisco_data = (struct cisco_packet*)(skb->data + sizeof
+ (struct hdlc_header));
switch(ntohl (cisco_data->type)) {
case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */
@@ -178,11 +220,11 @@
goto rx_error;
case CISCO_KEEPALIVE_REQ:
- hdlc->state.cisco.rxseq = ntohl(cisco_data->par1);
- if (hdlc->state.cisco.request_sent &&
- ntohl(cisco_data->par2)==hdlc->state.cisco.txseq) {
- hdlc->state.cisco.last_poll = jiffies;
- if (!hdlc->state.cisco.up) {
+ state(hdlc)->rxseq = ntohl(cisco_data->par1);
+ if (state(hdlc)->request_sent &&
+ ntohl(cisco_data->par2) == state(hdlc)->txseq) {
+ state(hdlc)->last_poll = jiffies;
+ if (!state(hdlc)->up) {
u32 sec, min, hrs, days;
sec = ntohl(cisco_data->time) / 1000;
min = sec / 60; sec -= min * 60;
@@ -193,7 +235,7 @@
dev->name, days, hrs,
min, sec);
netif_dormant_off(dev);
- hdlc->state.cisco.up = 1;
+ state(hdlc)->up = 1;
}
}
@@ -208,7 +250,7 @@
return NET_RX_DROP;
rx_error:
- hdlc->stats.rx_errors++; /* Mark error */
+ dev_to_desc(dev)->stats.rx_errors++; /* Mark error */
dev_kfree_skb_any(skb);
return NET_RX_DROP;
}
@@ -220,23 +262,22 @@
struct net_device *dev = (struct net_device *)arg;
hdlc_device *hdlc = dev_to_hdlc(dev);
- if (hdlc->state.cisco.up &&
- time_after(jiffies, hdlc->state.cisco.last_poll +
- hdlc->state.cisco.settings.timeout * HZ)) {
- hdlc->state.cisco.up = 0;
+ if (state(hdlc)->up &&
+ time_after(jiffies, state(hdlc)->last_poll +
+ state(hdlc)->settings.timeout * HZ)) {
+ state(hdlc)->up = 0;
printk(KERN_INFO "%s: Link down\n", dev->name);
netif_dormant_on(dev);
}
- cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ,
- ++hdlc->state.cisco.txseq,
- hdlc->state.cisco.rxseq);
- hdlc->state.cisco.request_sent = 1;
- hdlc->state.cisco.timer.expires = jiffies +
- hdlc->state.cisco.settings.interval * HZ;
- hdlc->state.cisco.timer.function = cisco_timer;
- hdlc->state.cisco.timer.data = arg;
- add_timer(&hdlc->state.cisco.timer);
+ cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, ++state(hdlc)->txseq,
+ state(hdlc)->rxseq);
+ state(hdlc)->request_sent = 1;
+ state(hdlc)->timer.expires = jiffies +
+ state(hdlc)->settings.interval * HZ;
+ state(hdlc)->timer.function = cisco_timer;
+ state(hdlc)->timer.data = arg;
+ add_timer(&state(hdlc)->timer);
}
@@ -244,15 +285,15 @@
static void cisco_start(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
- hdlc->state.cisco.up = 0;
- hdlc->state.cisco.request_sent = 0;
- hdlc->state.cisco.txseq = hdlc->state.cisco.rxseq = 0;
+ state(hdlc)->up = 0;
+ state(hdlc)->request_sent = 0;
+ state(hdlc)->txseq = state(hdlc)->rxseq = 0;
- init_timer(&hdlc->state.cisco.timer);
- hdlc->state.cisco.timer.expires = jiffies + HZ; /*First poll after 1s*/
- hdlc->state.cisco.timer.function = cisco_timer;
- hdlc->state.cisco.timer.data = (unsigned long)dev;
- add_timer(&hdlc->state.cisco.timer);
+ init_timer(&state(hdlc)->timer);
+ state(hdlc)->timer.expires = jiffies + HZ; /*First poll after 1s*/
+ state(hdlc)->timer.function = cisco_timer;
+ state(hdlc)->timer.data = (unsigned long)dev;
+ add_timer(&state(hdlc)->timer);
}
@@ -260,15 +301,24 @@
static void cisco_stop(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
- del_timer_sync(&hdlc->state.cisco.timer);
+ del_timer_sync(&state(hdlc)->timer);
netif_dormant_on(dev);
- hdlc->state.cisco.up = 0;
- hdlc->state.cisco.request_sent = 0;
+ state(hdlc)->up = 0;
+ state(hdlc)->request_sent = 0;
}
-int hdlc_cisco_ioctl(struct net_device *dev, struct ifreq *ifr)
+static struct hdlc_proto proto = {
+ .start = cisco_start,
+ .stop = cisco_stop,
+ .type_trans = cisco_type_trans,
+ .ioctl = cisco_ioctl,
+ .module = THIS_MODULE,
+};
+
+
+static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr)
{
cisco_proto __user *cisco_s = ifr->ifr_settings.ifs_ifsu.cisco;
const size_t size = sizeof(cisco_proto);
@@ -278,12 +328,14 @@
switch (ifr->ifr_settings.type) {
case IF_GET_PROTO:
+ if (dev_to_hdlc(dev)->proto != &proto)
+ return -EINVAL;
ifr->ifr_settings.type = IF_PROTO_CISCO;
if (ifr->ifr_settings.size < size) {
ifr->ifr_settings.size = size; /* data size wanted */
return -ENOBUFS;
}
- if (copy_to_user(cisco_s, &hdlc->state.cisco.settings, size))
+ if (copy_to_user(cisco_s, &state(hdlc)->settings, size))
return -EFAULT;
return 0;
@@ -302,19 +354,15 @@
return -EINVAL;
result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
-
if (result)
return result;
- hdlc_proto_detach(hdlc);
- memcpy(&hdlc->state.cisco.settings, &new_settings, size);
- memset(&hdlc->proto, 0, sizeof(hdlc->proto));
+ result = attach_hdlc_protocol(dev, &proto, cisco_rx,
+ sizeof(struct cisco_state));
+ if (result)
+ return result;
- hdlc->proto.start = cisco_start;
- hdlc->proto.stop = cisco_stop;
- hdlc->proto.netif_rx = cisco_rx;
- hdlc->proto.type_trans = cisco_type_trans;
- hdlc->proto.id = IF_PROTO_CISCO;
+ memcpy(&state(hdlc)->settings, &new_settings, size);
dev->hard_start_xmit = hdlc->xmit;
dev->hard_header = cisco_hard_header;
dev->hard_header_cache = NULL;
@@ -327,3 +375,25 @@
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("Cisco HDLC protocol support for generic HDLC");
+MODULE_LICENSE("GPL v2");