linux-brain/net/lapb/lapb_iface.c
Thomas Gleixner ee5d8f4d89 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41
Based on 1 normalized pattern(s):

  this module 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 18 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.008906948@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:12 +02:00

437 lines
8.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* LAPB release 002
*
* This code REQUIRES 2.1.15 or higher/ NET3.038
*
* History
* LAPB 001 Jonathan Naylor Started Coding
* LAPB 002 Jonathan Naylor New timer architecture.
* 2000-10-29 Henner Eisen lapb_data_indication() return status.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/inet.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <net/lapb.h>
static LIST_HEAD(lapb_list);
static DEFINE_RWLOCK(lapb_list_lock);
/*
* Free an allocated lapb control block.
*/
static void lapb_free_cb(struct lapb_cb *lapb)
{
kfree(lapb);
}
static __inline__ void lapb_hold(struct lapb_cb *lapb)
{
refcount_inc(&lapb->refcnt);
}
static __inline__ void lapb_put(struct lapb_cb *lapb)
{
if (refcount_dec_and_test(&lapb->refcnt))
lapb_free_cb(lapb);
}
/*
* Socket removal during an interrupt is now safe.
*/
static void __lapb_remove_cb(struct lapb_cb *lapb)
{
if (lapb->node.next) {
list_del(&lapb->node);
lapb_put(lapb);
}
}
EXPORT_SYMBOL(lapb_register);
/*
* Add a socket to the bound sockets list.
*/
static void __lapb_insert_cb(struct lapb_cb *lapb)
{
list_add(&lapb->node, &lapb_list);
lapb_hold(lapb);
}
static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
{
struct list_head *entry;
struct lapb_cb *lapb, *use = NULL;
list_for_each(entry, &lapb_list) {
lapb = list_entry(entry, struct lapb_cb, node);
if (lapb->dev == dev) {
use = lapb;
break;
}
}
if (use)
lapb_hold(use);
return use;
}
static struct lapb_cb *lapb_devtostruct(struct net_device *dev)
{
struct lapb_cb *rc;
read_lock_bh(&lapb_list_lock);
rc = __lapb_devtostruct(dev);
read_unlock_bh(&lapb_list_lock);
return rc;
}
/*
* Create an empty LAPB control block.
*/
static struct lapb_cb *lapb_create_cb(void)
{
struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);
if (!lapb)
goto out;
skb_queue_head_init(&lapb->write_queue);
skb_queue_head_init(&lapb->ack_queue);
timer_setup(&lapb->t1timer, NULL, 0);
timer_setup(&lapb->t2timer, NULL, 0);
lapb->t1 = LAPB_DEFAULT_T1;
lapb->t2 = LAPB_DEFAULT_T2;
lapb->n2 = LAPB_DEFAULT_N2;
lapb->mode = LAPB_DEFAULT_MODE;
lapb->window = LAPB_DEFAULT_WINDOW;
lapb->state = LAPB_STATE_0;
refcount_set(&lapb->refcnt, 1);
out:
return lapb;
}
int lapb_register(struct net_device *dev,
const struct lapb_register_struct *callbacks)
{
struct lapb_cb *lapb;
int rc = LAPB_BADTOKEN;
write_lock_bh(&lapb_list_lock);
lapb = __lapb_devtostruct(dev);
if (lapb) {
lapb_put(lapb);
goto out;
}
lapb = lapb_create_cb();
rc = LAPB_NOMEM;
if (!lapb)
goto out;
lapb->dev = dev;
lapb->callbacks = callbacks;
__lapb_insert_cb(lapb);
lapb_start_t1timer(lapb);
rc = LAPB_OK;
out:
write_unlock_bh(&lapb_list_lock);
return rc;
}
int lapb_unregister(struct net_device *dev)
{
struct lapb_cb *lapb;
int rc = LAPB_BADTOKEN;
write_lock_bh(&lapb_list_lock);
lapb = __lapb_devtostruct(dev);
if (!lapb)
goto out;
lapb_stop_t1timer(lapb);
lapb_stop_t2timer(lapb);
lapb_clear_queues(lapb);
__lapb_remove_cb(lapb);
lapb_put(lapb);
rc = LAPB_OK;
out:
write_unlock_bh(&lapb_list_lock);
return rc;
}
EXPORT_SYMBOL(lapb_unregister);
int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
{
int rc = LAPB_BADTOKEN;
struct lapb_cb *lapb = lapb_devtostruct(dev);
if (!lapb)
goto out;
parms->t1 = lapb->t1 / HZ;
parms->t2 = lapb->t2 / HZ;
parms->n2 = lapb->n2;
parms->n2count = lapb->n2count;
parms->state = lapb->state;
parms->window = lapb->window;
parms->mode = lapb->mode;
if (!timer_pending(&lapb->t1timer))
parms->t1timer = 0;
else
parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
if (!timer_pending(&lapb->t2timer))
parms->t2timer = 0;
else
parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
lapb_put(lapb);
rc = LAPB_OK;
out:
return rc;
}
EXPORT_SYMBOL(lapb_getparms);
int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
{
int rc = LAPB_BADTOKEN;
struct lapb_cb *lapb = lapb_devtostruct(dev);
if (!lapb)
goto out;
rc = LAPB_INVALUE;
if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
goto out_put;
if (lapb->state == LAPB_STATE_0) {
if (parms->mode & LAPB_EXTENDED) {
if (parms->window < 1 || parms->window > 127)
goto out_put;
} else {
if (parms->window < 1 || parms->window > 7)
goto out_put;
}
lapb->mode = parms->mode;
lapb->window = parms->window;
}
lapb->t1 = parms->t1 * HZ;
lapb->t2 = parms->t2 * HZ;
lapb->n2 = parms->n2;
rc = LAPB_OK;
out_put:
lapb_put(lapb);
out:
return rc;
}
EXPORT_SYMBOL(lapb_setparms);
int lapb_connect_request(struct net_device *dev)
{
struct lapb_cb *lapb = lapb_devtostruct(dev);
int rc = LAPB_BADTOKEN;
if (!lapb)
goto out;
rc = LAPB_OK;
if (lapb->state == LAPB_STATE_1)
goto out_put;
rc = LAPB_CONNECTED;
if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
goto out_put;
lapb_establish_data_link(lapb);
lapb_dbg(0, "(%p) S0 -> S1\n", lapb->dev);
lapb->state = LAPB_STATE_1;
rc = LAPB_OK;
out_put:
lapb_put(lapb);
out:
return rc;
}
EXPORT_SYMBOL(lapb_connect_request);
int lapb_disconnect_request(struct net_device *dev)
{
struct lapb_cb *lapb = lapb_devtostruct(dev);
int rc = LAPB_BADTOKEN;
if (!lapb)
goto out;
switch (lapb->state) {
case LAPB_STATE_0:
rc = LAPB_NOTCONNECTED;
goto out_put;
case LAPB_STATE_1:
lapb_dbg(1, "(%p) S1 TX DISC(1)\n", lapb->dev);
lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
lapb->state = LAPB_STATE_0;
lapb_start_t1timer(lapb);
rc = LAPB_NOTCONNECTED;
goto out_put;
case LAPB_STATE_2:
rc = LAPB_OK;
goto out_put;
}
lapb_clear_queues(lapb);
lapb->n2count = 0;
lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
lapb_start_t1timer(lapb);
lapb_stop_t2timer(lapb);
lapb->state = LAPB_STATE_2;
lapb_dbg(1, "(%p) S3 DISC(1)\n", lapb->dev);
lapb_dbg(0, "(%p) S3 -> S2\n", lapb->dev);
rc = LAPB_OK;
out_put:
lapb_put(lapb);
out:
return rc;
}
EXPORT_SYMBOL(lapb_disconnect_request);
int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
{
struct lapb_cb *lapb = lapb_devtostruct(dev);
int rc = LAPB_BADTOKEN;
if (!lapb)
goto out;
rc = LAPB_NOTCONNECTED;
if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
goto out_put;
skb_queue_tail(&lapb->write_queue, skb);
lapb_kick(lapb);
rc = LAPB_OK;
out_put:
lapb_put(lapb);
out:
return rc;
}
EXPORT_SYMBOL(lapb_data_request);
int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
{
struct lapb_cb *lapb = lapb_devtostruct(dev);
int rc = LAPB_BADTOKEN;
if (lapb) {
lapb_data_input(lapb, skb);
lapb_put(lapb);
rc = LAPB_OK;
}
return rc;
}
EXPORT_SYMBOL(lapb_data_received);
void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
{
if (lapb->callbacks->connect_confirmation)
lapb->callbacks->connect_confirmation(lapb->dev, reason);
}
void lapb_connect_indication(struct lapb_cb *lapb, int reason)
{
if (lapb->callbacks->connect_indication)
lapb->callbacks->connect_indication(lapb->dev, reason);
}
void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
{
if (lapb->callbacks->disconnect_confirmation)
lapb->callbacks->disconnect_confirmation(lapb->dev, reason);
}
void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
{
if (lapb->callbacks->disconnect_indication)
lapb->callbacks->disconnect_indication(lapb->dev, reason);
}
int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
{
if (lapb->callbacks->data_indication)
return lapb->callbacks->data_indication(lapb->dev, skb);
kfree_skb(skb);
return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
}
int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
{
int used = 0;
if (lapb->callbacks->data_transmit) {
lapb->callbacks->data_transmit(lapb->dev, skb);
used = 1;
}
return used;
}
static int __init lapb_init(void)
{
return 0;
}
static void __exit lapb_exit(void)
{
WARN_ON(!list_empty(&lapb_list));
}
MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
MODULE_LICENSE("GPL");
module_init(lapb_init);
module_exit(lapb_exit);