/* 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...)#endifstruct 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;}