diff options
Diffstat (limited to 'drivers/atm/atmtcp.c')
| -rw-r--r-- | drivers/atm/atmtcp.c | 499 |
1 files changed, 499 insertions, 0 deletions
diff --git a/drivers/atm/atmtcp.c b/drivers/atm/atmtcp.c new file mode 100644 index 000000000..96bea1ab1 --- /dev/null +++ b/drivers/atm/atmtcp.c @@ -0,0 +1,499 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* 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 <linux/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 = 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 = 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 const 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 const 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) { + atm_dev_put(dev); + return 0; + } + dev_data->persist = 0; + if (PRIV(dev)->vcc) { + atm_dev_put(dev); + 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); |