/* net/atm/signaling.c - ATM signaling */ /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */ #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__ #include <linux/errno.h> /* error codes */ #include <linux/kernel.h> /* printk */ #include <linux/skbuff.h> #include <linux/wait.h> #include <linux/sched.h> /* jiffies and HZ */ #include <linux/atm.h> /* ATM stuff */ #include <linux/atmsap.h> #include <linux/atmsvc.h> #include <linux/atmdev.h> #include <linux/bitops.h> #include <linux/slab.h> #include "resources.h" #include "signaling.h" #undef WAIT_FOR_DEMON /* #define this if system calls on SVC sockets should block until the demon runs. Danger: may cause nasty hangs if the demon crashes. */ struct atm_vcc *sigd = NULL; #ifdef WAIT_FOR_DEMON static DECLARE_WAIT_QUEUE_HEAD(sigd_sleep); #endif static void sigd_put_skb(struct sk_buff *skb) { #ifdef WAIT_FOR_DEMON DECLARE_WAITQUEUE(wait, current); add_wait_queue(&sigd_sleep, &wait); while (!sigd) { set_current_state(TASK_UNINTERRUPTIBLE); pr_debug("atmsvc: waiting for signaling daemon...\n"); schedule(); } current->state = TASK_RUNNING; remove_wait_queue(&sigd_sleep, &wait); #else if (!sigd) { pr_debug("atmsvc: no signaling daemon\n"); kfree_skb(skb); return; } #endif atm_force_charge(sigd, skb->truesize); skb_queue_tail(&sk_atm(sigd)->sk_receive_queue, skb); sk_atm(sigd)->sk_data_ready(sk_atm(sigd), skb->len); } static void modify_qos(struct atm_vcc *vcc, struct atmsvc_msg *msg) { struct sk_buff *skb; if (test_bit(ATM_VF_RELEASED, &vcc->flags) || !test_bit(ATM_VF_READY, &vcc->flags)) return; msg->type = as_error; if (!vcc->dev->ops->change_qos) msg->reply = -EOPNOTSUPP; else { /* should lock VCC */ msg->reply = vcc->dev->ops->change_qos(vcc, &msg->qos, msg->reply); if (!msg->reply) msg->type = as_okay; } /* * Should probably just turn around the old skb. But the, the buffer * space accounting needs to follow the change too. Maybe later. */ while (!(skb = alloc_skb(sizeof(struct atmsvc_msg), GFP_KERNEL))) schedule(); *(struct atmsvc_msg *)skb_put(skb, sizeof(struct atmsvc_msg)) = *msg; sigd_put_skb(skb); } static int sigd_send(struct atm_vcc *vcc, struct sk_buff *skb) { struct atmsvc_msg *msg; struct atm_vcc *session_vcc; struct sock *sk; msg = (struct atmsvc_msg *) skb->data; atomic_sub(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc); vcc = *(struct atm_vcc **) &msg->vcc; pr_debug("%d (0x%lx)\n", (int)msg->type, (unsigned long)vcc); sk = sk_atm(vcc); switch (msg->type) { case as_okay: sk->sk_err = -msg->reply; clear_bit(ATM_VF_WAITING, &vcc->flags); if (!*vcc->local.sas_addr.prv && !*vcc->local.sas_addr.pub) { vcc->local.sas_family = AF_ATMSVC; memcpy(vcc->local.sas_addr.prv, msg->local.sas_addr.prv, ATM_ESA_LEN); memcpy(vcc->local.sas_addr.pub, msg->local.sas_addr.pub, ATM_E164_LEN + 1); } session_vcc = vcc->session ? vcc->session : vcc; if (session_vcc->vpi || session_vcc->vci) break; session_vcc->itf = msg->pvc.sap_addr.itf; session_vcc->vpi = msg->pvc.sap_addr.vpi; session_vcc->vci = msg->pvc.sap_addr.vci; if (session_vcc->vpi || session_vcc->vci) session_vcc->qos = msg->qos; break; case as_error: clear_bit(ATM_VF_REGIS, &vcc->flags); clear_bit(ATM_VF_READY, &vcc->flags); sk->sk_err = -msg->reply; clear_bit(ATM_VF_WAITING, &vcc->flags); break; case as_indicate: vcc = *(struct atm_vcc **)&msg->listen_vcc; sk = sk_atm(vcc); pr_debug("as_indicate!!!\n"); lock_sock(sk); if (sk_acceptq_is_full(sk)) { sigd_enq(NULL, as_reject, vcc, NULL, NULL); dev_kfree_skb(skb); goto as_indicate_complete; } sk->sk_ack_backlog++; skb_queue_tail(&sk->sk_receive_queue, skb); pr_debug("waking sk_sleep(sk) 0x%p\n", sk_sleep(sk)); sk->sk_state_change(sk); as_indicate_complete: release_sock(sk); return 0; case as_close: set_bit(ATM_VF_RELEASED, &vcc->flags); vcc_release_async(vcc, msg->reply); goto out; case as_modify: modify_qos(vcc, msg); break; case as_addparty: case as_dropparty: sk->sk_err_soft = msg->reply; /* < 0 failure, otherwise ep_ref */ clear_bit(ATM_VF_WAITING, &vcc->flags); break; default: pr_alert("bad message type %d\n", (int)msg->type); return -EINVAL; } sk->sk_state_change(sk); out: dev_kfree_skb(skb); return 0; } void sigd_enq2(struct atm_vcc *vcc, enum atmsvc_msg_type type, struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc, const struct sockaddr_atmsvc *svc, const struct atm_qos *qos, int reply) { struct sk_buff *skb; struct atmsvc_msg *msg; static unsigned int session = 0; pr_debug("%d (0x%p)\n", (int)type, vcc); while (!(skb = alloc_skb(sizeof(struct atmsvc_msg), GFP_KERNEL))) schedule(); msg = (struct atmsvc_msg *)skb_put(skb, sizeof(struct atmsvc_msg)); memset(msg, 0, sizeof(*msg)); msg->type = type; *(struct atm_vcc **) &msg->vcc = vcc; *(struct atm_vcc **) &msg->listen_vcc = listen_vcc; msg->reply = reply; if (qos) msg->qos = *qos; if (vcc) msg->sap = vcc->sap; if (svc) msg->svc = *svc; if (vcc) msg->local = vcc->local; if (pvc) msg->pvc = *pvc; if (vcc) { if (type == as_connect && test_bit(ATM_VF_SESSION, &vcc->flags)) msg->session = ++session; /* every new pmp connect gets the next session number */ } sigd_put_skb(skb); if (vcc) set_bit(ATM_VF_REGIS, &vcc->flags); } void sigd_enq(struct atm_vcc *vcc, enum atmsvc_msg_type type, struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc, const struct sockaddr_atmsvc *svc) { sigd_enq2(vcc, type, listen_vcc, pvc, svc, vcc ? &vcc->qos : NULL, 0); /* other ISP applications may use "reply" */ } static void purge_vcc(struct atm_vcc *vcc) { if (sk_atm(vcc)->sk_family == PF_ATMSVC && !test_bit(ATM_VF_META, &vcc->flags)) { set_bit(ATM_VF_RELEASED, &vcc->flags); clear_bit(ATM_VF_REGIS, &vcc->flags); vcc_release_async(vcc, -EUNATCH); } } static void sigd_close(struct atm_vcc *vcc) { struct sock *s; int i; pr_debug("\n"); sigd = NULL; if (skb_peek(&sk_atm(vcc)->sk_receive_queue)) pr_err("closing with requests pending\n"); skb_queue_purge(&sk_atm(vcc)->sk_receive_queue); 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); purge_vcc(vcc); } } read_unlock(&vcc_sklist_lock); } static struct atmdev_ops sigd_dev_ops = { .close = sigd_close, .send = sigd_send }; static struct atm_dev sigd_dev = { .ops = &sigd_dev_ops, .type = "sig", .number = 999, .lock = __SPIN_LOCK_UNLOCKED(sigd_dev.lock) }; int sigd_attach(struct atm_vcc *vcc) { if (sigd) return -EADDRINUSE; pr_debug("\n"); sigd = vcc; vcc->dev = &sigd_dev; vcc_insert_socket(sk_atm(vcc)); set_bit(ATM_VF_META, &vcc->flags); set_bit(ATM_VF_READY, &vcc->flags); #ifdef WAIT_FOR_DEMON wake_up(&sigd_sleep); #endif return 0; }