common.c

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/* net/atm/common.c - ATM sockets (common part for PVC and SVC) */

/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */


#include <linux/config.h>
#include <linux/module.h>
#include <linux/kmod.h>
#include <linux/net.h>		/* struct socket, struct net_proto, struct
				   proto_ops */
#include <linux/atm.h>		/* ATM stuff */
#include <linux/atmdev.h>
#include <linux/atmclip.h>	/* CLIP_*ENCAP */
#include <linux/atmarp.h>	/* manifest constants */
#include <linux/sonet.h>	/* for ioctls */
#include <linux/socket.h>	/* SOL_SOCKET */
#include <linux/errno.h>	/* error codes */
#include <linux/capability.h>
#include <linux/mm.h>		/* verify_area */
#include <linux/sched.h>
#include <linux/time.h>		/* struct timeval */
#include <linux/skbuff.h>
#include <linux/bitops.h>
#include <net/sock.h>		/* struct sock */

#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/poll.h>

#if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
#include <linux/atmlec.h>
#include "lec.h"
#include "lec_arpc.h"
struct atm_lane_ops atm_lane_ops;
#endif
#ifdef CONFIG_ATM_LANE_MODULE
EXPORT_SYMBOL(atm_lane_ops);
#endif

#if defined(CONFIG_ATM_MPOA) || defined(CONFIG_ATM_MPOA_MODULE)
#include <linux/atmmpc.h>
#include "mpc.h"
struct atm_mpoa_ops atm_mpoa_ops;
#endif
#ifdef CONFIG_ATM_MPOA_MODULE
EXPORT_SYMBOL(atm_mpoa_ops);
#ifndef CONFIG_ATM_LANE_MODULE
EXPORT_SYMBOL(atm_lane_ops);
#endif
#endif

#if defined(CONFIG_ATM_TCP) || defined(CONFIG_ATM_TCP_MODULE)
#include <linux/atm_tcp.h>
#ifdef CONFIG_ATM_TCP_MODULE
struct atm_tcp_ops atm_tcp_ops;
EXPORT_SYMBOL(atm_tcp_ops);
#endif
#endif

#include "resources.h"		/* atm_find_dev */
#include "common.h"		/* prototypes */
#include "protocols.h"		/* atm_init_<transport> */
#include "addr.h"		/* address registry */
#ifdef CONFIG_ATM_CLIP
#include <net/atmclip.h>	/* for clip_create */
#endif
#include "signaling.h"		/* for WAITING and sigd_attach */


#if 0
#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
#else
#define DPRINTK(format,args...)
#endif

spinlock_t atm_dev_lock = SPIN_LOCK_UNLOCKED;

static struct sk_buff *alloc_tx(struct atm_vcc *vcc,unsigned int size)
{
	struct sk_buff *skb;

	if (atomic_read(&vcc->tx_inuse) && !atm_may_send(vcc,size)) {
		DPRINTK("Sorry: tx_inuse = %d, size = %d, sndbuf = %d\n",
		    atomic_read(&vcc->tx_inuse),size,vcc->sk->sndbuf);
		return NULL;
	}
	while (!(skb = alloc_skb(size,GFP_KERNEL))) schedule();
	DPRINTK("AlTx %d += %d\n",atomic_read(&vcc->tx_inuse),skb->truesize);
	atomic_add(skb->truesize+ATM_PDU_OVHD,&vcc->tx_inuse);
	return skb;
}


int atm_create(struct socket *sock,int protocol,int family)
{
	struct sock *sk;
	struct atm_vcc *vcc;

	sock->sk = NULL;
	if (sock->type == SOCK_STREAM) return -EINVAL;
	if (!(sk = alloc_atm_vcc_sk(family))) return -ENOMEM;
	vcc = sk->protinfo.af_atm;
	memset(&vcc->flags,0,sizeof(vcc->flags));
	vcc->dev = NULL;
	vcc->family = sock->ops->family;
	vcc->alloc_tx = alloc_tx;
	vcc->callback = NULL;
	memset(&vcc->local,0,sizeof(struct sockaddr_atmsvc));
	memset(&vcc->remote,0,sizeof(struct sockaddr_atmsvc));
	vcc->qos.txtp.max_sdu = 1 << 16; /* for meta VCs */
	atomic_set(&vcc->tx_inuse,0);
	atomic_set(&vcc->rx_inuse,0);
	vcc->push = NULL;
	vcc->pop = NULL;
	vcc->push_oam = NULL;
	vcc->vpi = vcc->vci = 0; /* no VCI/VPI yet */
	vcc->atm_options = vcc->aal_options = 0;
	vcc->timestamp.tv_sec = vcc->timestamp.tv_usec = 0;
	init_waitqueue_head(&vcc->sleep);
	skb_queue_head_init(&vcc->recvq);
	skb_queue_head_init(&vcc->listenq);
	sk->sleep = &vcc->sleep;
	sock->sk = sk;
	return 0;
}


void atm_release_vcc_sk(struct sock *sk,int free_sk)
{
	struct atm_vcc *vcc;
	struct sk_buff *skb;

	vcc = sk->protinfo.af_atm;
	clear_bit(ATM_VF_READY,&vcc->flags);
	if (vcc->dev) {
		if (vcc->dev->ops->close) vcc->dev->ops->close(vcc);
		if (vcc->push) vcc->push(vcc,NULL); /* atmarpd has no push */
		while ((skb = skb_dequeue(&vcc->recvq))) {
			atm_return(vcc,skb->truesize);
			if (vcc->dev->ops->free_rx_skb)
				vcc->dev->ops->free_rx_skb(vcc,skb);
			else kfree_skb(skb);
		}
		spin_lock (&atm_dev_lock);	
		fops_put (vcc->dev->ops);
		if (atomic_read(&vcc->rx_inuse))
			printk(KERN_WARNING "atm_release_vcc: strange ... "
			    "rx_inuse == %d after closing\n",
			    atomic_read(&vcc->rx_inuse));
		bind_vcc(vcc,NULL);
	} else
		spin_lock (&atm_dev_lock);	

	if (free_sk) free_atm_vcc_sk(sk);

	spin_unlock (&atm_dev_lock);
}


int atm_release(struct socket *sock)
{
	if (sock->sk)
		atm_release_vcc_sk(sock->sk,1);
	return 0;
}


void atm_async_release_vcc(struct atm_vcc *vcc,int reply)
{
	set_bit(ATM_VF_CLOSE,&vcc->flags);
	vcc->reply = reply;
	wake_up(&vcc->sleep);
}


EXPORT_SYMBOL(atm_async_release_vcc);


static int adjust_tp(struct atm_trafprm *tp,unsigned char aal)
{
	int max_sdu;

	if (!tp->traffic_class) return 0;
	switch (aal) {
		case ATM_AAL0:
			max_sdu = ATM_CELL_SIZE-1;
			break;
		case ATM_AAL34:
			max_sdu = ATM_MAX_AAL34_PDU;
			break;
		default:
			printk(KERN_WARNING "ATM: AAL problems ... "
			    "(%d)\n",aal);
			/* fall through */
		case ATM_AAL5:
			max_sdu = ATM_MAX_AAL5_PDU;
	}
	if (!tp->max_sdu) tp->max_sdu = max_sdu;
	else if (tp->max_sdu > max_sdu) return -EINVAL;
	if (!tp->max_cdv) tp->max_cdv = ATM_MAX_CDV;
	return 0;
}


static int atm_do_connect_dev(struct atm_vcc *vcc,struct atm_dev *dev,int vpi,
    int vci)
{
	int error;

	if ((vpi != ATM_VPI_UNSPEC && vpi != ATM_VPI_ANY &&
	    vpi >> dev->ci_range.vpi_bits) || (vci != ATM_VCI_UNSPEC &&
	    vci != ATM_VCI_ANY && vci >> dev->ci_range.vci_bits))
		return -EINVAL;
	if (vci > 0 && vci < ATM_NOT_RSV_VCI && !capable(CAP_NET_BIND_SERVICE))
		return -EPERM;
	error = 0;
	bind_vcc(vcc,dev);
	switch (vcc->qos.aal) {
		case ATM_AAL0:
			error = atm_init_aal0(vcc);
			vcc->stats = &dev->stats.aal0;
			break;
		case ATM_AAL34:
			error = atm_init_aal34(vcc);
			vcc->stats = &dev->stats.aal34;
			break;
		case ATM_NO_AAL:
			/* ATM_AAL5 is also used in the "0 for default" case */
			vcc->qos.aal = ATM_AAL5;
			/* fall through */
		case ATM_AAL5:
			error = atm_init_aal5(vcc);
			vcc->stats = &dev->stats.aal5;
			break;
		default:
			error = -EPROTOTYPE;
	}
	if (!error) error = adjust_tp(&vcc->qos.txtp,vcc->qos.aal);
	if (!error) error = adjust_tp(&vcc->qos.rxtp,vcc->qos.aal);
	if (error) {
		bind_vcc(vcc,NULL);
		return error;
	}
	DPRINTK("VCC %d.%d, AAL %d\n",vpi,vci,vcc->qos.aal);
	DPRINTK("  TX: %d, PCR %d..%d, SDU %d\n",vcc->qos.txtp.traffic_class,
	    vcc->qos.txtp.min_pcr,vcc->qos.txtp.max_pcr,vcc->qos.txtp.max_sdu);
	DPRINTK("  RX: %d, PCR %d..%d, SDU %d\n",vcc->qos.rxtp.traffic_class,
	    vcc->qos.rxtp.min_pcr,vcc->qos.rxtp.max_pcr,vcc->qos.rxtp.max_sdu);
	fops_get (dev->ops);
	if (dev->ops->open) {
		error = dev->ops->open(vcc,vpi,vci);
		if (error) {
			fops_put (dev->ops);
			bind_vcc(vcc,NULL);
			return error;
		}
	}
	return 0;
}


static int atm_do_connect(struct atm_vcc *vcc,int itf,int vpi,int vci)
{
	struct atm_dev *dev;
	int return_val;

	spin_lock (&atm_dev_lock);
	dev = atm_find_dev(itf);
	if (!dev)
		return_val =  -ENODEV;
	else
		return_val = atm_do_connect_dev(vcc,dev,vpi,vci);

	spin_unlock (&atm_dev_lock);

	return return_val;
}


int atm_connect_vcc(struct atm_vcc *vcc,int itf,short vpi,int vci)
{
	if (vpi != ATM_VPI_UNSPEC && vci != ATM_VCI_UNSPEC)
		clear_bit(ATM_VF_PARTIAL,&vcc->flags);
	else if (test_bit(ATM_VF_PARTIAL,&vcc->flags)) return -EINVAL;
	printk(KERN_DEBUG "atm_connect (TX: cl %d,bw %d-%d,sdu %d; "
	    "RX: cl %d,bw %d-%d,sdu %d,AAL %s%d)\n",
	    vcc->qos.txtp.traffic_class,vcc->qos.txtp.min_pcr,
	    vcc->qos.txtp.max_pcr,vcc->qos.txtp.max_sdu,
	    vcc->qos.rxtp.traffic_class,vcc->qos.rxtp.min_pcr,
	    vcc->qos.rxtp.max_pcr,vcc->qos.rxtp.max_sdu,
	    vcc->qos.aal == ATM_AAL5 ? "" : vcc->qos.aal == ATM_AAL0 ? "" :
	    " ??? code ",vcc->qos.aal == ATM_AAL0 ? 0 : vcc->qos.aal);
	if (!test_bit(ATM_VF_HASQOS,&vcc->flags)) return -EBADFD;
	if (vcc->qos.txtp.traffic_class == ATM_ANYCLASS ||
	    vcc->qos.rxtp.traffic_class == ATM_ANYCLASS)
		return -EINVAL;
	if (itf != ATM_ITF_ANY) {
		int error;

		error = atm_do_connect(vcc,itf,vpi,vci);
		if (error) return error;
	}
	else {
		struct atm_dev *dev;

		spin_lock (&atm_dev_lock);
		for (dev = atm_devs; dev; dev = dev->next)
			if (!atm_do_connect_dev(vcc,dev,vpi,vci)) break;
		spin_unlock (&atm_dev_lock);
		if (!dev) return -ENODEV;
	}
	if (vpi == ATM_VPI_UNSPEC || vci == ATM_VCI_UNSPEC)
		set_bit(ATM_VF_PARTIAL,&vcc->flags);
	return 0;
}


int atm_connect(struct socket *sock,int itf,short vpi,int vci)
{
	int error;

	DPRINTK("atm_connect (vpi %d, vci %d)\n",vpi,vci);
	if (sock->state == SS_CONNECTED) return -EISCONN;
	if (sock->state != SS_UNCONNECTED) return -EINVAL;
	if (!(vpi || vci)) return -EINVAL;
	error = atm_connect_vcc(ATM_SD(sock),itf,vpi,vci);
	if (error) return error;
	if (test_bit(ATM_VF_READY,&ATM_SD(sock)->flags))
		sock->state = SS_CONNECTED;
	return 0;
}


int atm_recvmsg(struct socket *sock,struct msghdr *m,int total_len,
    int flags,struct scm_cookie *scm)
{
	DECLARE_WAITQUEUE(wait,current);
	struct atm_vcc *vcc;
	struct sk_buff *skb;
	int eff_len,error;
	void *buff;
	int size;

	if (sock->state != SS_CONNECTED) return -ENOTCONN;
	if (flags & ~MSG_DONTWAIT) return -EOPNOTSUPP;
	if (m->msg_iovlen != 1) return -ENOSYS; /* fix this later @@@ */
	buff = m->msg_iov->iov_base;
	size = m->msg_iov->iov_len;
	vcc = ATM_SD(sock);
	add_wait_queue(&vcc->sleep,&wait);
	set_current_state(TASK_INTERRUPTIBLE);
	error = 1; /* <= 0 is error */
	while (!(skb = skb_dequeue(&vcc->recvq))) {
		if (test_bit(ATM_VF_RELEASED,&vcc->flags) ||
		    test_bit(ATM_VF_CLOSE,&vcc->flags)) {
			error = vcc->reply;
			break;
		}
		if (!test_bit(ATM_VF_READY,&vcc->flags)) {
			error = 0;
			break;
		}
		if (flags & MSG_DONTWAIT) {
			error = -EAGAIN;
			break;
		}
		schedule();
		set_current_state(TASK_INTERRUPTIBLE);
		if (signal_pending(current)) {
			error = -ERESTARTSYS;
			break;
		}
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&vcc->sleep,&wait);
	if (error <= 0) return error;
	vcc->timestamp = skb->stamp;
	eff_len = skb->len > size ? size : skb->len;
	if (vcc->dev->ops->feedback)
		vcc->dev->ops->feedback(vcc,skb,(unsigned long) skb->data,
		    (unsigned long) buff,eff_len);
	DPRINTK("RcvM %d -= %d\n",atomic_read(&vcc->rx_inuse),skb->truesize);
	atm_return(vcc,skb->truesize);
	if (ATM_SKB(skb)->iovcnt) { /* @@@ hack */
		/* iovcnt set, use scatter-gather for receive */
		int el, cnt;
		struct iovec *iov = (struct iovec *)skb->data;
		unsigned char *p = (unsigned char *)buff;

		el = eff_len;
		error = 0;
		for (cnt = 0; (cnt < ATM_SKB(skb)->iovcnt) && el; cnt++) {
/*printk("s-g???: %p -> %p (%d)\n",iov->iov_base,p,iov->iov_len);*/
			error = copy_to_user(p,iov->iov_base,
			    (iov->iov_len > el) ? el : iov->iov_len) ?
			    -EFAULT : 0;
			if (error) break;
			p += iov->iov_len;
			el -= (iov->iov_len > el)?el:iov->iov_len;
			iov++;
		}
		if (!vcc->dev->ops->free_rx_skb) kfree_skb(skb);
		else vcc->dev->ops->free_rx_skb(vcc, skb);
		return error ? error : eff_len;
	}
	error = copy_to_user(buff,skb->data,eff_len) ? -EFAULT : 0;
	if (!vcc->dev->ops->free_rx_skb) kfree_skb(skb);
	else vcc->dev->ops->free_rx_skb(vcc, skb);
	return error ? error : eff_len;
}


int atm_sendmsg(struct socket *sock,struct msghdr *m,int total_len,
    struct scm_cookie *scm)
{
	DECLARE_WAITQUEUE(wait,current);
	struct atm_vcc *vcc;
	struct sk_buff *skb;
	int eff,error;
	const void *buff;
	int size;

	if (sock->state != SS_CONNECTED) return -ENOTCONN;
	if (m->msg_name) return -EISCONN;
	if (m->msg_iovlen != 1) return -ENOSYS; /* fix this later @@@ */
	buff = m->msg_iov->iov_base;
	size = m->msg_iov->iov_len;
	vcc = ATM_SD(sock);
	if (test_bit(ATM_VF_RELEASED,&vcc->flags) ||
	    test_bit(ATM_VF_CLOSE,&vcc->flags))
		return vcc->reply;
	if (!test_bit(ATM_VF_READY,&vcc->flags)) return -EPIPE;
	if (!size) return 0;
	if (size < 0 || size > vcc->qos.txtp.max_sdu) return -EMSGSIZE;
	/* verify_area is done by net/socket.c */
	eff = (size+3) & ~3; /* align to word boundary */
	add_wait_queue(&vcc->sleep,&wait);
	set_current_state(TASK_INTERRUPTIBLE);
	error = 0;
	while (!(skb = vcc->alloc_tx(vcc,eff))) {
		if (m->msg_flags & MSG_DONTWAIT) {
			error = -EAGAIN;
			break;
		}
		schedule();
		set_current_state(TASK_INTERRUPTIBLE);
		if (signal_pending(current)) {
			error = -ERESTARTSYS;
			break;
		}
		if (test_bit(ATM_VF_RELEASED,&vcc->flags) ||
		    test_bit(ATM_VF_CLOSE,&vcc->flags)) {
			error = vcc->reply;
			break;
		}
		if (!test_bit(ATM_VF_READY,&vcc->flags)) {
			error = -EPIPE;
			break;
		}
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&vcc->sleep,&wait);
	if (error) return error;
	skb->dev = NULL; /* for paths shared with net_device interfaces */
	ATM_SKB(skb)->iovcnt = 0;
	ATM_SKB(skb)->atm_options = vcc->atm_options;
	if (copy_from_user(skb_put(skb,size),buff,size)) {
		kfree_skb(skb);
		return -EFAULT;
	}
	if (eff != size) memset(skb->data+size,0,eff-size);
	error = vcc->dev->ops->send(vcc,skb);
	return error ? error : size;
}


unsigned int atm_poll(struct file *file,struct socket *sock,poll_table *wait)
{
	struct atm_vcc *vcc;
	unsigned int mask;

	vcc = ATM_SD(sock);
	poll_wait(file,&vcc->sleep,wait);
	mask = 0;
	if (skb_peek(&vcc->recvq) || skb_peek(&vcc->listenq))
		mask |= POLLIN | POLLRDNORM;
	if (test_bit(ATM_VF_RELEASED,&vcc->flags) ||
	    test_bit(ATM_VF_CLOSE,&vcc->flags))
		mask |= POLLHUP;
	if (sock->state != SS_CONNECTING) {
		if (vcc->qos.txtp.traffic_class != ATM_NONE &&
		    vcc->qos.txtp.max_sdu+atomic_read(&vcc->tx_inuse)+
		    ATM_PDU_OVHD <= vcc->sk->sndbuf)
			mask |= POLLOUT | POLLWRNORM;
	}
	else if (vcc->reply != WAITING) {
			mask |= POLLOUT | POLLWRNORM;
			if (vcc->reply) mask |= POLLERR;
		}
	return mask;
}


static void copy_aal_stats(struct k_atm_aal_stats *from,
    struct atm_aal_stats *to)
{
#define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
	__AAL_STAT_ITEMS
#undef __HANDLE_ITEM
}


static void subtract_aal_stats(struct k_atm_aal_stats *from,
    struct atm_aal_stats *to)
{
#define __HANDLE_ITEM(i) atomic_sub(to->i,&from->i)
	__AAL_STAT_ITEMS
#undef __HANDLE_ITEM
}


static int fetch_stats(struct atm_dev *dev,struct atm_dev_stats *arg,int zero)
{
	struct atm_dev_stats tmp;
	int error = 0;

	copy_aal_stats(&dev->stats.aal0,&tmp.aal0);
	copy_aal_stats(&dev->stats.aal34,&tmp.aal34);
	copy_aal_stats(&dev->stats.aal5,&tmp.aal5);
	if (arg) error = copy_to_user(arg,&tmp,sizeof(tmp));
	if (zero && !error) {
		subtract_aal_stats(&dev->stats.aal0,&tmp.aal0);
		subtract_aal_stats(&dev->stats.aal34,&tmp.aal34);
		subtract_aal_stats(&dev->stats.aal5,&tmp.aal5);
	}
	return error ? -EFAULT : 0;
}


int atm_ioctl(struct socket *sock,unsigned int cmd,unsigned long arg)
{
	struct atm_dev *dev;
	struct atm_vcc *vcc;
	int *tmp_buf;
	void *buf;
	int error,len,size,number, ret_val;

	ret_val = 0;
	spin_lock (&atm_dev_lock);
	vcc = ATM_SD(sock);
	switch (cmd) {
		case SIOCOUTQ:
			if (sock->state != SS_CONNECTED ||
			    !test_bit(ATM_VF_READY,&vcc->flags)) {
				ret_val =  -EINVAL;
				goto done;
			}
			ret_val =  put_user(vcc->sk->sndbuf-
			    atomic_read(&vcc->tx_inuse)-ATM_PDU_OVHD,
			    (int *) arg) ? -EFAULT : 0;
			goto done;
		case SIOCINQ:
			{
				struct sk_buff *skb;

				if (sock->state != SS_CONNECTED) {
					ret_val = -EINVAL;
					goto done;
				}
				skb = skb_peek(&vcc->recvq);
				ret_val = put_user(skb ? skb->len : 0,(int *) arg)
				    ? -EFAULT : 0;
				goto done;
			}