- 根目录:
- drivers
- atm
- atmtcp.c
/* drivers/atm/atmtcp.c - ATM over TCP "device" driver */
/* Written 1997-2000 by Werner Almesberger, EPFL LRC/ICA */
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/atmdev.h>
#include <linux/atm_tcp.h>
#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
#include <linux/atomic.h>
extern int atm_init_aal5(struct atm_vcc *vcc); /* "raw" AAL5 transport */
#define PRIV(dev) ((struct atmtcp_dev_data *) ((dev)->dev_data))
struct atmtcp_dev_data {
struct atm_vcc *vcc; /* control VCC; NULL if detached */
int persist; /* non-zero if persistent */
};
#define DEV_LABEL "atmtcp"
#define MAX_VPI_BITS 8 /* simplifies life */
#define MAX_VCI_BITS 16
/*
* Hairy code ahead: the control VCC may be closed while we're still
* waiting for an answer, so we need to re-validate out_vcc every once
* in a while.
*/
static int atmtcp_send_control(struct atm_vcc *vcc,int type,
const struct atmtcp_control *msg,int flag)
{
DECLARE_WAITQUEUE(wait,current);
struct atm_vcc *out_vcc;
struct sk_buff *skb;
struct atmtcp_control *new_msg;
int old_test;
int error = 0;
out_vcc = PRIV(vcc->dev) ? PRIV(vcc->dev)->vcc : NULL;
if (!out_vcc) return -EUNATCH;
skb = alloc_skb(sizeof(*msg),GFP_KERNEL);
if (!skb) return -ENOMEM;
mb();
out_vcc = PRIV(vcc->dev) ? PRIV(vcc->dev)->vcc : NULL;
if (!out_vcc) {
dev_kfree_skb(skb);
return -EUNATCH;
}
atm_force_charge(out_vcc,skb->truesize);
new_msg = (struct atmtcp_control *) skb_put(skb,sizeof(*new_msg));
*new_msg = *msg;
new_msg->hdr.length = ATMTCP_HDR_MAGIC;
new_msg->type = type;
memset(&new_msg->vcc,0,sizeof(atm_kptr_t));
*(struct atm_vcc **) &new_msg->vcc = vcc;
old_test = test_bit(flag,&vcc->flags);
out_vcc->push(out_vcc,skb);
add_wait_queue(sk_sleep(sk_atm(vcc)), &wait);
while (test_bit(flag,&vcc->flags) == old_test) {
mb();
out_vcc = PRIV(vcc->dev) ? PRIV(vcc->dev)->vcc : NULL;
if (!out_vcc) {
error = -EUNATCH;
break;
}
set_current_state(TASK_UNINTERRUPTIBLE);
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk_atm(vcc)), &wait);
return error;
}
static int atmtcp_recv_control(const struct atmtcp_control *msg)
{
struct atm_vcc *vcc = *(struct atm_vcc **) &msg->vcc;
vcc->vpi = msg->addr.sap_addr.vpi;
vcc->vci = msg->addr.sap_addr.vci;
vcc->qos = msg->qos;
sk_atm(vcc)->sk_err = -msg->result;
switch (msg->type) {
case ATMTCP_CTRL_OPEN:
change_bit(ATM_VF_READY,&vcc->flags);
break;
case ATMTCP_CTRL_CLOSE:
change_bit(ATM_VF_ADDR,&vcc->flags);
break;
default:
printk(KERN_ERR "atmtcp_recv_control: unknown type %d\n",
msg->type);
return -EINVAL;
}
wake_up(sk_sleep(sk_atm(vcc)));
return 0;
}
static void atmtcp_v_dev_close(struct atm_dev *dev)
{
/* Nothing.... Isn't this simple :-) -- REW */
}
static int atmtcp_v_open(struct atm_vcc *vcc)
{
struct atmtcp_control msg;
int error;
short vpi = vcc->vpi;
int vci = vcc->vci;
memset(&msg,0,sizeof(msg));
msg.addr.sap_family = AF_ATMPVC;
msg.hdr.vpi = htons(vpi);
msg.addr.sap_addr.vpi = vpi;
msg.hdr.vci = htons(vci);
msg.addr.sap_addr.vci = vci;
if (vpi == ATM_VPI_UNSPEC || vci == ATM_VCI_UNSPEC) return 0;
msg.type = ATMTCP_CTRL_OPEN;
msg.qos = vcc->qos;
set_bit(ATM_VF_ADDR,&vcc->flags);
clear_bit(ATM_VF_READY,&vcc->flags); /* just in case ... */
error = atmtcp_send_control(vcc,ATMTCP_CTRL_OPEN,&msg,ATM_VF_READY);
if (error) return error;
return -sk_atm(vcc)->sk_err;
}
static void atmtcp_v_close(struct atm_vcc *vcc)
{
struct atmtcp_control msg;
memset(&msg,0,sizeof(msg));
msg.addr.sap_family = AF_ATMPVC;
msg.addr.sap_addr.vpi = vcc->vpi;
msg.addr.sap_addr.vci = vcc->vci;
clear_bit(ATM_VF_READY,&vcc->flags);
(void) atmtcp_send_control(vcc,ATMTCP_CTRL_CLOSE,&msg,ATM_VF_ADDR);
}
static int atmtcp_v_ioctl(struct atm_dev *dev,unsigned int cmd,void __user *arg)
{
struct atm_cirange ci;
struct atm_vcc *vcc;
struct sock *s;
int i;
if (cmd != ATM_SETCIRANGE) return -ENOIOCTLCMD;
if (copy_from_user(&ci, arg,sizeof(ci))) return -EFAULT;
if (ci.vpi_bits == ATM_CI_MAX) ci.vpi_bits = MAX_VPI_BITS;
if (ci.vci_bits == ATM_CI_MAX) ci.vci_bits = MAX_VCI_BITS;
if (ci.vpi_bits > MAX_VPI_BITS || ci.vpi_bits < 0 ||
ci.vci_bits > MAX_VCI_BITS || ci.vci_bits < 0) return -EINVAL;
read_lock(&vcc_sklist_lock);
for(i = 0; i < VCC_HTABLE_SIZE; ++i) {
struct hlist_head *head = &vcc_hash[i];
sk_for_each(s, head) {
vcc = atm_sk(s);
if (vcc->dev != dev)
continue;
if ((vcc->vpi >> ci.vpi_bits) ||
(vcc->vci >> ci.vci_bits)) {
read_unlock(&vcc_sklist_lock);
return -EBUSY;
}
}
}
read_unlock(&vcc_sklist_lock);
dev->ci_range = ci;
return 0;
}
static int atmtcp_v_send(struct atm_vcc *vcc,struct sk_buff *skb)
{
struct atmtcp_dev_data *dev_data;
struct atm_vcc *out_vcc=NULL; /* Initializer quietens GCC warning */
struct sk_buff *new_skb;
struct atmtcp_hdr *hdr;
int size;
if (vcc->qos.txtp.traffic_class == ATM_NONE) {
if (vcc->pop) vcc->pop(vcc,skb);
else dev_kfree_skb(skb);
return -EINVAL;
}
dev_data = PRIV(vcc->dev);
if (dev_data) out_vcc = dev_data->vcc;
if (!dev_data || !out_vcc) {
if (vcc->pop) vcc->pop(vcc,skb);
else dev_kfree_skb(skb);
if (dev_data) return 0;
atomic_inc(&vcc->stats->tx_err);
return -ENOLINK;
}
size = skb->len+sizeof(struct atmtcp_hdr);
new_skb = atm_alloc_charge(out_vcc,size,GFP_ATOMIC);
if (!new_skb) {
if (vcc->pop) vcc->pop(vcc,skb);
else dev_kfree_skb(skb);
atomic_inc(&vcc->stats->tx_err);
return -ENOBUFS;
}
hdr = (void *) skb_put(new_skb,sizeof(struct atmtcp_hdr));
hdr->vpi = htons(vcc->vpi);
hdr->vci = htons(vcc->vci);
hdr->length = htonl(skb->len);
skb_copy_from_linear_data(skb, skb_put(new_skb, skb->len), skb->len);
if (vcc->pop) vcc->pop(vcc,skb);
else dev_kfree_skb(skb);
out_vcc->push(out_vcc,new_skb);
atomic_inc(&vcc->stats->tx);
atomic_inc(&out_vcc->stats->rx);
return 0;
}
static int atmtcp_v_proc(struct atm_dev *dev,loff_t *pos,char *page)
{
struct atmtcp_dev_data *dev_data = PRIV(dev);
if (*pos) return 0;
if (!dev_data->persist) return sprintf(page,"ephemeral\n");
return sprintf(page,"persistent, %sconnected\n",
dev_data->vcc ? "" : "dis");
}
static void atmtcp_c_close(struct atm_vcc *vcc)
{
struct atm_dev *atmtcp_dev;
struct atmtcp_dev_data *dev_data;
atmtcp_dev = (struct atm_dev *) vcc->dev_data;
dev_data = PRIV(atmtcp_dev);
dev_data->vcc = NULL;
if (dev_data->persist) return;
atmtcp_dev->dev_data = NULL;
kfree(dev_data);
atm_dev_deregister(atmtcp_dev);
vcc->dev_data = NULL;
module_put(THIS_MODULE);
}
static struct atm_vcc *find_vcc(struct atm_dev *dev, short vpi, int vci)
{
struct hlist_head *head;
struct atm_vcc *vcc;
struct sock *s;
head = &vcc_hash[vci & (VCC_HTABLE_SIZE -1)];
sk_for_each(s, head) {
vcc = atm_sk(s);
if (vcc->dev == dev &&
vcc->vci == vci && vcc->vpi == vpi &&
vcc->qos.rxtp.traffic_class != ATM_NONE) {
return vcc;
}
}
return NULL;
}
static int atmtcp_c_send(struct atm_vcc *vcc,struct sk_buff *skb)
{
struct atm_dev *dev;
struct atmtcp_hdr *hdr;
struct atm_vcc *out_vcc;
struct sk_buff *new_skb;
int result = 0;
if (!skb->len) return 0;
dev = vcc->dev_data;
hdr = (struct atmtcp_hdr *) skb->data;
if (hdr->length == ATMTCP_HDR_MAGIC) {
result = atmtcp_recv_control(
(struct atmtcp_control *) skb->data);
goto done;
}
read_lock(&vcc_sklist_lock);
out_vcc = find_vcc(dev, ntohs(hdr->vpi), ntohs(hdr->vci));
read_unlock(&vcc_sklist_lock);
if (!out_vcc) {
result = -EUNATCH;
atomic_inc(&vcc->stats->tx_err);
goto done;
}
skb_pull(skb,sizeof(struct atmtcp_hdr));
new_skb = atm_alloc_charge(out_vcc,skb->len,GFP_KERNEL);
if (!new_skb) {
result = -ENOBUFS;
goto done;
}
__net_timestamp(new_skb);
skb_copy_from_linear_data(skb, skb_put(new_skb, skb->len), skb->len);
out_vcc->push(out_vcc,new_skb);
atomic_inc(&vcc->stats->tx);
atomic_inc(&out_vcc->stats->rx);
done:
if (vcc->pop) vcc->pop(vcc,skb);
else dev_kfree_skb(skb);
return result;
}
/*
* Device operations for the virtual ATM devices created by ATMTCP.
*/
static struct atmdev_ops atmtcp_v_dev_ops = {
.dev_close = atmtcp_v_dev_close,
.open = atmtcp_v_open,
.close = atmtcp_v_close,
.ioctl = atmtcp_v_ioctl,
.send = atmtcp_v_send,
.proc_read = atmtcp_v_proc,
.owner = THIS_MODULE
};
/*
* Device operations for the ATMTCP control device.
*/
static struct atmdev_ops atmtcp_c_dev_ops = {
.close = atmtcp_c_close,
.send = atmtcp_c_send
};
static struct atm_dev atmtcp_control_dev = {
.ops = &atmtcp_c_dev_ops,
.type = "atmtcp",
.number = 999,
.lock = __SPIN_LOCK_UNLOCKED(atmtcp_control_dev.lock)
};
static int atmtcp_create(int itf,int persist,struct atm_dev **result)
{
struct atmtcp_dev_data *dev_data;
struct atm_dev *dev;
dev_data = kmalloc(sizeof(*dev_data),GFP_KERNEL);
if (!dev_data)
return -ENOMEM;
dev = atm_dev_register(DEV_LABEL,NULL,&atmtcp_v_dev_ops,itf,NULL);
if (!dev) {
kfree(dev_data);
return itf == -1 ? -ENOMEM : -EBUSY;
}
dev->ci_range.vpi_bits = MAX_VPI_BITS;
dev->ci_range.vci_bits = MAX_VCI_BITS;
dev->dev_data = dev_data;
PRIV(dev)->vcc = NULL;
PRIV(dev)->persist = persist;
if (result) *result = dev;
return 0;
}
static int atmtcp_attach(struct atm_vcc *vcc,int itf)
{
struct atm_dev *dev;
dev = NULL;
if (itf != -1) dev = atm_dev_lookup(itf);
if (dev) {
if (dev->ops != &atmtcp_v_dev_ops) {
atm_dev_put(dev);
return -EMEDIUMTYPE;
}
if (PRIV(dev)->vcc) {
atm_dev_put(dev);
return -EBUSY;
}
}
else {
int error;
error = atmtcp_create(itf,0,&dev);
if (error) return error;
}
PRIV(dev)->vcc = vcc;
vcc->dev = &atmtcp_control_dev;
vcc_insert_socket(sk_atm(vcc));
set_bit(ATM_VF_META,&vcc->flags);
set_bit(ATM_VF_READY,&vcc->flags);
vcc->dev_data = dev;
(void) atm_init_aal5(vcc); /* @@@ losing AAL in transit ... */
vcc->stats = &atmtcp_control_dev.stats.aal5;
return dev->number;
}
static int atmtcp_create_persistent(int itf)
{
return atmtcp_create(itf,1,NULL);
}
static int atmtcp_remove_persistent(int itf)
{
struct atm_dev *dev;
struct atmtcp_dev_data *dev_data;
dev = atm_dev_lookup(itf);
if (!dev) return -ENODEV;
if (dev->ops != &atmtcp_v_dev_ops) {
atm_dev_put(dev);
return -EMEDIUMTYPE;
}
dev_data = PRIV(dev);
if (!dev_data->persist) return 0;
dev_data->persist = 0;
if (PRIV(dev)->vcc) return 0;
kfree(dev_data);
atm_dev_put(dev);
atm_dev_deregister(dev);
return 0;
}
static int atmtcp_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
int err = 0;
struct atm_vcc *vcc = ATM_SD(sock);
if (cmd != SIOCSIFATMTCP && cmd != ATMTCP_CREATE && cmd != ATMTCP_REMOVE)
return -ENOIOCTLCMD;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
switch (cmd) {
case SIOCSIFATMTCP:
err = atmtcp_attach(vcc, (int) arg);
if (err >= 0) {
sock->state = SS_CONNECTED;
__module_get(THIS_MODULE);
}
break;
case ATMTCP_CREATE:
err = atmtcp_create_persistent((int) arg);
break;
case ATMTCP_REMOVE:
err = atmtcp_remove_persistent((int) arg);
break;
}
return err;
}
static struct atm_ioctl atmtcp_ioctl_ops = {
.owner = THIS_MODULE,
.ioctl = atmtcp_ioctl,
};
static __init int atmtcp_init(void)
{
register_atm_ioctl(&atmtcp_ioctl_ops);
return 0;
}
static void __exit atmtcp_exit(void)
{
deregister_atm_ioctl(&atmtcp_ioctl_ops);
}
MODULE_LICENSE("GPL");
module_init(atmtcp_init);
module_exit(atmtcp_exit);