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/* net/atm/signaling.c - ATM signaling */
/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
#include <linux/errno.h> /* error codes */
#include <linux/kernel.h> /* printk */
#include <linux/skbuff.h>
#include <linux/wait.h>
#include <linux/sched.h> /* jiffies and HZ */
#include <linux/atm.h> /* ATM stuff */
#include <linux/atmsap.h>
#include <linux/atmsvc.h>
#include <linux/atmdev.h>
#include <linux/bitops.h>
#include "resources.h"
#include "signaling.h"
#undef WAIT_FOR_DEMON /* #define this if system calls on SVC sockets
should block until the demon runs.
Danger: may cause nasty hangs if the demon
crashes. */
#if 0
#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
#else
#define DPRINTK(format,args...)
#endif
struct atm_vcc *sigd = NULL;
static DECLARE_WAIT_QUEUE_HEAD(sigd_sleep);
extern spinlock_t atm_dev_lock;
static void sigd_put_skb(struct sk_buff *skb)
{
#ifdef WAIT_FOR_DEMON
static unsigned long silence = 0;
DECLARE_WAITQUEUE(wait,current);
add_wait_queue(&sigd_sleep,&wait);
while (!sigd) {
set_current_state(TASK_UNINTERRUPTIBLE);
if (time_after(jiffies, silence) || silence == 0) {
printk(KERN_INFO "atmsvc: waiting for signaling demon "
"...\n");
silence = (jiffies+30*HZ)|1;
}
schedule();
}
current->state = TASK_RUNNING;
remove_wait_queue(&sigd_sleep,&wait);
#else
if (!sigd) {
printk(KERN_WARNING "atmsvc: no signaling demon\n");
kfree_skb(skb);
return;
}
#endif
atm_force_charge(sigd,skb->truesize);
skb_queue_tail(&sigd->recvq,skb);
wake_up(&sigd->sleep);
}
static void modify_qos(struct atm_vcc *vcc,struct atmsvc_msg *msg)
{
struct sk_buff *skb;
if (test_bit(ATM_VF_RELEASED,&vcc->flags) ||
!test_bit(ATM_VF_READY,&vcc->flags))
return;
msg->type = as_error;
if (!vcc->dev->ops->change_qos) msg->reply = -EOPNOTSUPP;
else {
/* should lock VCC */
msg->reply = vcc->dev->ops->change_qos(vcc,&msg->qos,
msg->reply);
if (!msg->reply) msg->type = as_okay;
}
/*
* Should probably just turn around the old skb. But the, the buffer
* space accounting needs to follow the change too. Maybe later.
*/
while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL)))
schedule();
*(struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg)) = *msg;
sigd_put_skb(skb);
}
static int sigd_send(struct atm_vcc *vcc,struct sk_buff *skb)
{
struct atmsvc_msg *msg;
struct atm_vcc *session_vcc;
msg = (struct atmsvc_msg *) skb->data;
atomic_sub(skb->truesize+ATM_PDU_OVHD,&vcc->tx_inuse);
DPRINTK("sigd_send %d (0x%lx)\n",(int) msg->type,
(unsigned long) msg->vcc);
vcc = *(struct atm_vcc **) &msg->vcc;
switch (msg->type) {
case as_okay:
vcc->reply = msg->reply;
if (!*vcc->local.sas_addr.prv &&
!*vcc->local.sas_addr.pub) {
vcc->local.sas_family = AF_ATMSVC;
memcpy(vcc->local.sas_addr.prv,
msg->local.sas_addr.prv,ATM_ESA_LEN);
memcpy(vcc->local.sas_addr.pub,
msg->local.sas_addr.pub,ATM_E164_LEN+1);
}
session_vcc = vcc->session ? vcc->session : vcc;
if (session_vcc->vpi || session_vcc->vci) break;
session_vcc->itf = msg->pvc.sap_addr.itf;
session_vcc->vpi = msg->pvc.sap_addr.vpi;
session_vcc->vci = msg->pvc.sap_addr.vci;
if (session_vcc->vpi || session_vcc->vci)
session_vcc->qos = msg->qos;
break;
case as_error:
clear_bit(ATM_VF_REGIS,&vcc->flags);
clear_bit(ATM_VF_READY,&vcc->flags);
vcc->reply = msg->reply;
break;
case as_indicate:
vcc = *(struct atm_vcc **) &msg->listen_vcc;
DPRINTK("as_indicate!!!\n");
if (!vcc->backlog_quota) {
sigd_enq(0,as_reject,vcc,NULL,NULL);
return 0;
}
vcc->backlog_quota--;
skb_queue_tail(&vcc->listenq,skb);
if (vcc->callback) {
DPRINTK("waking vcc->sleep 0x%p\n",
&vcc->sleep);
vcc->callback(vcc);
}
return 0;
case as_close:
set_bit(ATM_VF_RELEASED,&vcc->flags);
clear_bit(ATM_VF_READY,&vcc->flags);
vcc->reply = msg->reply;
break;
case as_modify:
modify_qos(vcc,msg);
break;
default:
printk(KERN_ALERT "sigd_send: bad message type %d\n",
(int) msg->type);
return -EINVAL;
}
if (vcc->callback) vcc->callback(vcc);
dev_kfree_skb(skb);
return 0;
}
void sigd_enq2(struct atm_vcc *vcc,enum atmsvc_msg_type type,
struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc,
const struct sockaddr_atmsvc *svc,const struct atm_qos *qos,int reply)
{
struct sk_buff *skb;
struct atmsvc_msg *msg;
DPRINTK("sigd_enq %d (0x%p)\n",(int) type,vcc);
while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL)))
schedule();
msg = (struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg));
memset(msg,0,sizeof(*msg));
msg->type = type;
*(struct atm_vcc **) &msg->vcc = vcc;
*(struct atm_vcc **) &msg->listen_vcc = listen_vcc;
msg->reply = reply;
if (qos) msg->qos = *qos;
if (vcc) msg->sap = vcc->sap;
if (svc) msg->svc = *svc;
if (vcc) msg->local = vcc->local;
if (pvc) msg->pvc = *pvc;
sigd_put_skb(skb);
if (vcc) set_bit(ATM_VF_REGIS,&vcc->flags);
}
void sigd_enq(struct atm_vcc *vcc,enum atmsvc_msg_type type,
struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc,
const struct sockaddr_atmsvc *svc)
{
sigd_enq2(vcc,type,listen_vcc,pvc,svc,vcc ? &vcc->qos : NULL,0);
/* other ISP applications may use "reply" */
}
static void purge_vccs(struct atm_vcc *vcc)
{
while (vcc) {
if (vcc->family == PF_ATMSVC &&
!test_bit(ATM_VF_META,&vcc->flags)) {
set_bit(ATM_VF_RELEASED,&vcc->flags);
vcc->reply = -EUNATCH;
wake_up(&vcc->sleep);
}
vcc = vcc->next;
}
}
static void sigd_close(struct atm_vcc *vcc)
{
struct atm_dev *dev;
DPRINTK("sigd_close\n");
sigd = NULL;
if (skb_peek(&vcc->recvq))
printk(KERN_ERR "sigd_close: closing with requests pending\n");
skb_queue_purge(&vcc->recvq);
purge_vccs(nodev_vccs);
spin_lock (&atm_dev_lock);
for (dev = atm_devs; dev; dev = dev->next) purge_vccs(dev->vccs);
spin_unlock (&atm_dev_lock);
}
static struct atmdev_ops sigd_dev_ops = {
close: sigd_close,
send: sigd_send
};
static struct atm_dev sigd_dev = {
&sigd_dev_ops,
NULL, /* no PHY */
"sig", /* type */
999, /* dummy device number */
NULL,NULL, /* pretend not to have any VCCs */
NULL,NULL, /* no data */
{ 0 }, /* no flags */
NULL, /* no local address */
{ 0 } /* no ESI, no statistics */
};
int sigd_attach(struct atm_vcc *vcc)
{
if (sigd) return -EADDRINUSE;
DPRINTK("sigd_attach\n");
sigd = vcc;
bind_vcc(vcc,&sigd_dev);
set_bit(ATM_VF_META,&vcc->flags);
set_bit(ATM_VF_READY,&vcc->flags);
wake_up(&sigd_sleep);
return 0;
}
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