linux/drivers/atm/atmtcp.c
Dan Williams d9ca676bcb atm: correct sysfs 'device' link creation and parent relationships
The ATM subsystem was incorrectly creating the 'device' link for ATM
nodes in sysfs.  This led to incorrect device/parent relationships
exposed by sysfs and udev.  Instead of rolling the 'device' link by hand
in the generic ATM code, pass each ATM driver's bus device down to the
sysfs code and let sysfs do this stuff correctly.

Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-10 15:45:05 -08:00

490 lines
11 KiB
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 <asm/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 hlist_node *node;
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, node, 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 hlist_node *node;
struct sock *s;
head = &vcc_hash[vci & (VCC_HTABLE_SIZE -1)];
sk_for_each(s, node, 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) {
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) 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);