/* 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 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) { 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);