net/atm/common.c

root/net/atm/common.c
// SPDX-License-Identifier: GPL-2.0-only
/* net/atm/common.c - ATM sockets (common part for PVC and SVC) */

/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */

#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

#include <linux/module.h>
#include <linux/kmod.h>
#include <linux/net.h>          /* struct socket, struct proto_ops */
#include <linux/atm.h>          /* ATM stuff */
#include <linux/atmdev.h>
#include <linux/socket.h>       /* SOL_SOCKET */
#include <linux/errno.h>        /* error codes */
#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/sched/signal.h>
#include <linux/time64.h>       /* 64-bit time for seconds */
#include <linux/skbuff.h>
#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <net/sock.h>           /* struct sock */
#include <linux/uaccess.h>
#include <linux/poll.h>

#include <linux/atomic.h>

#include "resources.h"          /* atm_find_dev */
#include "common.h"             /* prototypes */
#include "protocols.h"          /* atm_init_<transport> */
#include "addr.h"               /* address registry */
#include "signaling.h"          /* for WAITING and sigd_attach */

struct hlist_head vcc_hash[VCC_HTABLE_SIZE];
EXPORT_SYMBOL(vcc_hash);

DEFINE_RWLOCK(vcc_sklist_lock);
EXPORT_SYMBOL(vcc_sklist_lock);

static ATOMIC_NOTIFIER_HEAD(atm_dev_notify_chain);

static void __vcc_insert_socket(struct sock *sk)
{
        struct atm_vcc *vcc = atm_sk(sk);
        struct hlist_head *head = &vcc_hash[vcc->vci & (VCC_HTABLE_SIZE - 1)];
        sk->sk_hash = vcc->vci & (VCC_HTABLE_SIZE - 1);
        sk_add_node(sk, head);
}

void vcc_insert_socket(struct sock *sk)
{
        write_lock_irq(&vcc_sklist_lock);
        __vcc_insert_socket(sk);
        write_unlock_irq(&vcc_sklist_lock);
}
EXPORT_SYMBOL(vcc_insert_socket);

static void vcc_remove_socket(struct sock *sk)
{
        write_lock_irq(&vcc_sklist_lock);
        sk_del_node_init(sk);
        write_unlock_irq(&vcc_sklist_lock);
}

static bool vcc_tx_ready(struct atm_vcc *vcc, unsigned int size)
{
        struct sock *sk = sk_atm(vcc);

        if (sk_wmem_alloc_get(sk) && !atm_may_send(vcc, size)) {
                pr_debug("Sorry: wmem_alloc = %d, size = %d, sndbuf = %d\n",
                         sk_wmem_alloc_get(sk), size, sk->sk_sndbuf);
                return false;
        }
        return true;
}

static void vcc_sock_destruct(struct sock *sk)
{
        if (atomic_read(&sk->sk_rmem_alloc))
                printk(KERN_DEBUG "%s: rmem leakage (%d bytes) detected.\n",
                       __func__, atomic_read(&sk->sk_rmem_alloc));

        if (refcount_read(&sk->sk_wmem_alloc))
                printk(KERN_DEBUG "%s: wmem leakage (%d bytes) detected.\n",
                       __func__, refcount_read(&sk->sk_wmem_alloc));
}

static void vcc_def_wakeup(struct sock *sk)
{
        struct socket_wq *wq;

        rcu_read_lock();
        wq = rcu_dereference(sk->sk_wq);
        if (skwq_has_sleeper(wq))
                wake_up(&wq->wait);
        rcu_read_unlock();
}

static inline int vcc_writable(struct sock *sk)
{
        struct atm_vcc *vcc = atm_sk(sk);

        return (vcc->qos.txtp.max_sdu +
                refcount_read(&sk->sk_wmem_alloc)) <= sk->sk_sndbuf;
}

static void vcc_write_space(struct sock *sk)
{
        struct socket_wq *wq;

        rcu_read_lock();

        if (vcc_writable(sk)) {
                wq = rcu_dereference(sk->sk_wq);
                if (skwq_has_sleeper(wq))
                        wake_up_interruptible(&wq->wait);

                sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
        }

        rcu_read_unlock();
}

static void vcc_release_cb(struct sock *sk)
{
        struct atm_vcc *vcc = atm_sk(sk);

        if (vcc->release_cb)
                vcc->release_cb(vcc);
}

static struct proto vcc_proto = {
        .name     = "VCC",
        .owner    = THIS_MODULE,
        .obj_size = sizeof(struct atm_vcc),
        .release_cb = vcc_release_cb,
};

int vcc_create(struct net *net, struct socket *sock, int protocol, int family, int kern)
{
        struct sock *sk;
        struct atm_vcc *vcc;

        sock->sk = NULL;
        if (sock->type == SOCK_STREAM)
                return -EINVAL;
        sk = sk_alloc(net, family, GFP_KERNEL, &vcc_proto, kern);
        if (!sk)
                return -ENOMEM;
        sock_init_data(sock, sk);
        sk->sk_state_change = vcc_def_wakeup;
        sk->sk_write_space = vcc_write_space;

        vcc = atm_sk(sk);
        vcc->dev = NULL;
        memset(&vcc->local, 0, sizeof(struct sockaddr_atmsvc));
        memset(&vcc->remote, 0, sizeof(struct sockaddr_atmsvc));
        vcc->qos.txtp.max_sdu = 1 << 16; /* for meta VCs */
        refcount_set(&sk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
        atomic_set(&sk->sk_rmem_alloc, 0);
        vcc->push = NULL;
        vcc->pop = NULL;
        vcc->owner = NULL;
        vcc->push_oam = NULL;
        vcc->release_cb = NULL;
        vcc->vpi = vcc->vci = 0; /* no VCI/VPI yet */
        vcc->atm_options = vcc->aal_options = 0;
        sk->sk_destruct = vcc_sock_destruct;
        return 0;
}

static void vcc_destroy_socket(struct sock *sk)
{
        struct atm_vcc *vcc = atm_sk(sk);
        struct sk_buff *skb;

        set_bit(ATM_VF_CLOSE, &vcc->flags);
        clear_bit(ATM_VF_READY, &vcc->flags);
        if (vcc->dev && vcc->dev->ops->close)
                vcc->dev->ops->close(vcc);
        if (vcc->push)
                vcc->push(vcc, NULL); /* atmarpd has no push */
        module_put(vcc->owner);

        while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
                atm_return(vcc, skb->truesize);
                kfree_skb(skb);
        }

        if (vcc->dev && vcc->dev->ops->owner) {
                module_put(vcc->dev->ops->owner);
                atm_dev_put(vcc->dev);
        }

        vcc_remove_socket(sk);
}

int vcc_release(struct socket *sock)
{
        struct sock *sk = sock->sk;

        if (sk) {
                lock_sock(sk);
                vcc_destroy_socket(sock->sk);
                release_sock(sk);
                sock_put(sk);
        }

        return 0;
}

void vcc_release_async(struct atm_vcc *vcc, int reply)
{
        struct sock *sk = sk_atm(vcc);

        set_bit(ATM_VF_CLOSE, &vcc->flags);
        sk->sk_shutdown |= RCV_SHUTDOWN;
        sk->sk_err = -reply;
        clear_bit(ATM_VF_WAITING, &vcc->flags);
        sk->sk_state_change(sk);
}
EXPORT_SYMBOL(vcc_release_async);

void vcc_process_recv_queue(struct atm_vcc *vcc)
{
        struct sk_buff_head queue, *rq;
        struct sk_buff *skb, *tmp;
        unsigned long flags;

        __skb_queue_head_init(&queue);
        rq = &sk_atm(vcc)->sk_receive_queue;

        spin_lock_irqsave(&rq->lock, flags);
        skb_queue_splice_init(rq, &queue);
        spin_unlock_irqrestore(&rq->lock, flags);

        skb_queue_walk_safe(&queue, skb, tmp) {
                __skb_unlink(skb, &queue);
                vcc->push(vcc, skb);
        }
}
EXPORT_SYMBOL(vcc_process_recv_queue);

void atm_dev_signal_change(struct atm_dev *dev, char signal)
{
        pr_debug("%s signal=%d dev=%p number=%d dev->signal=%d\n",
                __func__, signal, dev, dev->number, dev->signal);

        /* atm driver sending invalid signal */
        WARN_ON(signal < ATM_PHY_SIG_LOST || signal > ATM_PHY_SIG_FOUND);

        if (dev->signal == signal)
                return; /* no change */

        dev->signal = signal;

        atomic_notifier_call_chain(&atm_dev_notify_chain, signal, dev);
}
EXPORT_SYMBOL(atm_dev_signal_change);

void atm_dev_release_vccs(struct atm_dev *dev)
{
        int i;

        write_lock_irq(&vcc_sklist_lock);
        for (i = 0; i < VCC_HTABLE_SIZE; i++) {
                struct hlist_head *head = &vcc_hash[i];
                struct hlist_node *tmp;
                struct sock *s;
                struct atm_vcc *vcc;

                sk_for_each_safe(s, tmp, head) {
                        vcc = atm_sk(s);
                        if (vcc->dev == dev) {
                                vcc_release_async(vcc, -EPIPE);
                                sk_del_node_init(s);
                        }
                }
        }
        write_unlock_irq(&vcc_sklist_lock);
}
EXPORT_SYMBOL(atm_dev_release_vccs);

static int adjust_tp(struct atm_trafprm *tp, unsigned char aal)
{
        int max_sdu;

        if (!tp->traffic_class)
                return 0;
        switch (aal) {
        case ATM_AAL0:
                max_sdu = ATM_CELL_SIZE-1;
                break;
        case ATM_AAL34:
                max_sdu = ATM_MAX_AAL34_PDU;
                break;
        default:
                pr_warn("AAL problems ... (%d)\n", aal);
                fallthrough;
        case ATM_AAL5:
                max_sdu = ATM_MAX_AAL5_PDU;
        }
        if (!tp->max_sdu)
                tp->max_sdu = max_sdu;
        else if (tp->max_sdu > max_sdu)
                return -EINVAL;
        if (!tp->max_cdv)
                tp->max_cdv = ATM_MAX_CDV;
        return 0;
}

static int check_ci(const struct atm_vcc *vcc, short vpi, int vci)
{
        struct hlist_head *head = &vcc_hash[vci & (VCC_HTABLE_SIZE - 1)];
        struct sock *s;
        struct atm_vcc *walk;

        sk_for_each(s, head) {
                walk = atm_sk(s);
                if (walk->dev != vcc->dev)
                        continue;
                if (test_bit(ATM_VF_ADDR, &walk->flags) && walk->vpi == vpi &&
                    walk->vci == vci && ((walk->qos.txtp.traffic_class !=
                    ATM_NONE && vcc->qos.txtp.traffic_class != ATM_NONE) ||
                    (walk->qos.rxtp.traffic_class != ATM_NONE &&
                    vcc->qos.rxtp.traffic_class != ATM_NONE)))
                        return -EADDRINUSE;
        }

        /* allow VCCs with same VPI/VCI iff they don't collide on
           TX/RX (but we may refuse such sharing for other reasons,
           e.g. if protocol requires to have both channels) */

        return 0;
}

static int find_ci(const struct atm_vcc *vcc, short *vpi, int *vci)
{
        static short p;        /* poor man's per-device cache */
        static int c;
        short old_p;
        int old_c;
        int err;

        if (*vpi != ATM_VPI_ANY && *vci != ATM_VCI_ANY) {
                err = check_ci(vcc, *vpi, *vci);
                return err;
        }
        /* last scan may have left values out of bounds for current device */
        if (*vpi != ATM_VPI_ANY)
                p = *vpi;
        else if (p >= 1 << vcc->dev->ci_range.vpi_bits)
                p = 0;
        if (*vci != ATM_VCI_ANY)
                c = *vci;
        else if (c < ATM_NOT_RSV_VCI || c >= 1 << vcc->dev->ci_range.vci_bits)
                        c = ATM_NOT_RSV_VCI;
        old_p = p;
        old_c = c;
        do {
                if (!check_ci(vcc, p, c)) {
                        *vpi = p;
                        *vci = c;
                        return 0;
                }
                if (*vci == ATM_VCI_ANY) {
                        c++;
                        if (c >= 1 << vcc->dev->ci_range.vci_bits)
                                c = ATM_NOT_RSV_VCI;
                }
                if ((c == ATM_NOT_RSV_VCI || *vci != ATM_VCI_ANY) &&
                    *vpi == ATM_VPI_ANY) {
                        p++;
                        if (p >= 1 << vcc->dev->ci_range.vpi_bits)
                                p = 0;
                }
        } while (old_p != p || old_c != c);
        return -EADDRINUSE;
}

static int __vcc_connect(struct atm_vcc *vcc, struct atm_dev *dev, short vpi,
                         int vci)
{
        struct sock *sk = sk_atm(vcc);
        int error;

        if ((vpi != ATM_VPI_UNSPEC && vpi != ATM_VPI_ANY &&
            vpi >> dev->ci_range.vpi_bits) || (vci != ATM_VCI_UNSPEC &&
            vci != ATM_VCI_ANY && vci >> dev->ci_range.vci_bits))
                return -EINVAL;
        if (vci > 0 && vci < ATM_NOT_RSV_VCI && !capable(CAP_NET_BIND_SERVICE))
                return -EPERM;
        error = -ENODEV;
        if (!try_module_get(dev->ops->owner))
                return error;
        vcc->dev = dev;
        write_lock_irq(&vcc_sklist_lock);
        if (test_bit(ATM_DF_REMOVED, &dev->flags) ||
            (error = find_ci(vcc, &vpi, &vci))) {
                write_unlock_irq(&vcc_sklist_lock);
                goto fail_module_put;
        }
        vcc->vpi = vpi;
        vcc->vci = vci;
        __vcc_insert_socket(sk);
        write_unlock_irq(&vcc_sklist_lock);
        switch (vcc->qos.aal) {
        case ATM_AAL0:
                error = atm_init_aal0(vcc);
                vcc->stats = &dev->stats.aal0;
                break;
        case ATM_AAL34:
                error = atm_init_aal34(vcc);
                vcc->stats = &dev->stats.aal34;
                break;
        case ATM_NO_AAL:
                /* ATM_AAL5 is also used in the "0 for default" case */
                vcc->qos.aal = ATM_AAL5;
                fallthrough;
        case ATM_AAL5:
                error = atm_init_aal5(vcc);
                vcc->stats = &dev->stats.aal5;
                break;
        default:
                error = -EPROTOTYPE;
        }
        if (!error)
                error = adjust_tp(&vcc->qos.txtp, vcc->qos.aal);
        if (!error)
                error = adjust_tp(&vcc->qos.rxtp, vcc->qos.aal);
        if (error)
                goto fail;
        pr_debug("VCC %d.%d, AAL %d\n", vpi, vci, vcc->qos.aal);
        pr_debug("  TX: %d, PCR %d..%d, SDU %d\n",
                 vcc->qos.txtp.traffic_class,
                 vcc->qos.txtp.min_pcr,
                 vcc->qos.txtp.max_pcr,
                 vcc->qos.txtp.max_sdu);
        pr_debug("  RX: %d, PCR %d..%d, SDU %d\n",
                 vcc->qos.rxtp.traffic_class,
                 vcc->qos.rxtp.min_pcr,
                 vcc->qos.rxtp.max_pcr,
                 vcc->qos.rxtp.max_sdu);

        if (dev->ops->open) {
                error = dev->ops->open(vcc);
                if (error)
                        goto fail;
        }
        return 0;

fail:
        vcc_remove_socket(sk);
fail_module_put:
        module_put(dev->ops->owner);
        /* ensure we get dev module ref count correct */
        vcc->dev = NULL;
        return error;
}

int vcc_connect(struct socket *sock, int itf, short vpi, int vci)
{
        struct atm_dev *dev;
        struct atm_vcc *vcc = ATM_SD(sock);
        int error;

        pr_debug("(vpi %d, vci %d)\n", vpi, vci);
        if (sock->state == SS_CONNECTED)
                return -EISCONN;
        if (sock->state != SS_UNCONNECTED)
                return -EINVAL;
        if (!(vpi || vci))
                return -EINVAL;

        if (vpi != ATM_VPI_UNSPEC && vci != ATM_VCI_UNSPEC)
                clear_bit(ATM_VF_PARTIAL, &vcc->flags);
        else
                if (test_bit(ATM_VF_PARTIAL, &vcc->flags))
                        return -EINVAL;
        pr_debug("(TX: cl %d,bw %d-%d,sdu %d; "
                 "RX: cl %d,bw %d-%d,sdu %d,AAL %s%d)\n",
                 vcc->qos.txtp.traffic_class, vcc->qos.txtp.min_pcr,
                 vcc->qos.txtp.max_pcr, vcc->qos.txtp.max_sdu,
                 vcc->qos.rxtp.traffic_class, vcc->qos.rxtp.min_pcr,
                 vcc->qos.rxtp.max_pcr, vcc->qos.rxtp.max_sdu,
                 vcc->qos.aal == ATM_AAL5 ? "" :
                 vcc->qos.aal == ATM_AAL0 ? "" : " ??? code ",
                 vcc->qos.aal == ATM_AAL0 ? 0 : vcc->qos.aal);
        if (!test_bit(ATM_VF_HASQOS, &vcc->flags))
                return -EBADFD;
        if (vcc->qos.txtp.traffic_class == ATM_ANYCLASS ||
            vcc->qos.rxtp.traffic_class == ATM_ANYCLASS)
                return -EINVAL;
        if (likely(itf != ATM_ITF_ANY)) {
                dev = try_then_request_module(atm_dev_lookup(itf),
                                              "atm-device-%d", itf);
        } else {
                dev = NULL;
                mutex_lock(&atm_dev_mutex);
                if (!list_empty(&atm_devs)) {
                        dev = list_entry(atm_devs.next,
                                         struct atm_dev, dev_list);
                        atm_dev_hold(dev);
                }
                mutex_unlock(&atm_dev_mutex);
        }
        if (!dev)
                return -ENODEV;
        error = __vcc_connect(vcc, dev, vpi, vci);
        if (error) {
                atm_dev_put(dev);
                return error;
        }
        if (vpi == ATM_VPI_UNSPEC || vci == ATM_VCI_UNSPEC)
                set_bit(ATM_VF_PARTIAL, &vcc->flags);
        if (test_bit(ATM_VF_READY, &ATM_SD(sock)->flags))
                sock->state = SS_CONNECTED;
        return 0;
}

int vcc_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
                int flags)
{
        struct sock *sk = sock->sk;
        struct atm_vcc *vcc;
        struct sk_buff *skb;
        int copied, error = -EINVAL;

        if (sock->state != SS_CONNECTED)
                return -ENOTCONN;

        /* only handle MSG_DONTWAIT and MSG_PEEK */
        if (flags & ~(MSG_DONTWAIT | MSG_PEEK))
                return -EOPNOTSUPP;

        vcc = ATM_SD(sock);
        if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
            test_bit(ATM_VF_CLOSE, &vcc->flags) ||
            !test_bit(ATM_VF_READY, &vcc->flags))
                return 0;

        skb = skb_recv_datagram(sk, flags, &error);
        if (!skb)
                return error;

        copied = skb->len;
        if (copied > size) {
                copied = size;
                msg->msg_flags |= MSG_TRUNC;
        }

        error = skb_copy_datagram_msg(skb, 0, msg, copied);
        if (error)
                return error;
        sock_recv_cmsgs(msg, sk, skb);

        if (!(flags & MSG_PEEK)) {
                pr_debug("%d -= %d\n", atomic_read(&sk->sk_rmem_alloc),
                         skb->truesize);
                atm_return(vcc, skb->truesize);
        }

        skb_free_datagram(sk, skb);
        return copied;
}

int vcc_sendmsg(struct socket *sock, struct msghdr *m, size_t size)
{
        struct sock *sk = sock->sk;
        DEFINE_WAIT(wait);
        struct atm_vcc *vcc;
        struct sk_buff *skb;
        int eff, error;

        lock_sock(sk);
        if (sock->state != SS_CONNECTED) {
                error = -ENOTCONN;
                goto out;
        }
        if (m->msg_name) {
                error = -EISCONN;
                goto out;
        }
        vcc = ATM_SD(sock);
        if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
            test_bit(ATM_VF_CLOSE, &vcc->flags) ||
            !test_bit(ATM_VF_READY, &vcc->flags)) {
                error = -EPIPE;
                send_sig(SIGPIPE, current, 0);
                goto out;
        }
        if (!size) {
                error = 0;
                goto out;
        }
        if (size > vcc->qos.txtp.max_sdu) {
                error = -EMSGSIZE;
                goto out;
        }

        eff = (size+3) & ~3; /* align to word boundary */
        prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
        error = 0;
        while (!vcc_tx_ready(vcc, eff)) {
                if (m->msg_flags & MSG_DONTWAIT) {
                        error = -EAGAIN;
                        break;
                }
                schedule();
                if (signal_pending(current)) {
                        error = -ERESTARTSYS;
                        break;
                }
                if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
                    test_bit(ATM_VF_CLOSE, &vcc->flags) ||
                    !test_bit(ATM_VF_READY, &vcc->flags)) {
                        error = -EPIPE;
                        send_sig(SIGPIPE, current, 0);
                        break;
                }
                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
        }
        finish_wait(sk_sleep(sk), &wait);
        if (error)
                goto out;

        skb = alloc_skb(eff, GFP_KERNEL);
        if (!skb) {
                error = -ENOMEM;
                goto out;
        }
        pr_debug("%d += %d\n", sk_wmem_alloc_get(sk), skb->truesize);
        atm_account_tx(vcc, skb);

        skb->dev = NULL; /* for paths shared with net_device interfaces */
        if (!copy_from_iter_full(skb_put(skb, size), size, &m->msg_iter)) {
                error = -EFAULT;
                goto free_skb;
        }
        if (eff != size)
                memset(skb->data + size, 0, eff-size);

        if (vcc->dev->ops->pre_send) {
                error = vcc->dev->ops->pre_send(vcc, skb);
                if (error)
                        goto free_skb;
        }

        error = vcc->dev->ops->send(vcc, skb);
        error = error ? error : size;
out:
        release_sock(sk);
        return error;
free_skb:
        atm_return_tx(vcc, skb);
        kfree_skb(skb);
        goto out;
}

__poll_t vcc_poll(struct file *file, struct socket *sock, poll_table *wait)
{
        struct sock *sk = sock->sk;
        struct atm_vcc *vcc;
        __poll_t mask;

        sock_poll_wait(file, sock, wait);
        mask = 0;

        vcc = ATM_SD(sock);

        /* exceptional events */
        if (sk->sk_err)
                mask = EPOLLERR;

        if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
            test_bit(ATM_VF_CLOSE, &vcc->flags))
                mask |= EPOLLHUP;

        /* readable? */
        if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
                mask |= EPOLLIN | EPOLLRDNORM;

        /* writable? */
        if (sock->state == SS_CONNECTING &&
            test_bit(ATM_VF_WAITING, &vcc->flags))
                return mask;

        if (vcc->qos.txtp.traffic_class != ATM_NONE &&
            vcc_writable(sk))
                mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;

        return mask;
}

static int atm_change_qos(struct atm_vcc *vcc, struct atm_qos *qos)
{
        int error;

        /*
         * Don't let the QoS change the already connected AAL type nor the
         * traffic class.
         */
        if (qos->aal != vcc->qos.aal ||
            qos->rxtp.traffic_class != vcc->qos.rxtp.traffic_class ||
            qos->txtp.traffic_class != vcc->qos.txtp.traffic_class)
                return -EINVAL;
        error = adjust_tp(&qos->txtp, qos->aal);
        if (!error)
                error = adjust_tp(&qos->rxtp, qos->aal);
        if (error)
                return error;
        if (!vcc->dev->ops->change_qos)
                return -EOPNOTSUPP;
        if (sk_atm(vcc)->sk_family == AF_ATMPVC)
                return vcc->dev->ops->change_qos(vcc, qos, ATM_MF_SET);
        return svc_change_qos(vcc, qos);
}

static int check_tp(const struct atm_trafprm *tp)
{
        /* @@@ Should be merged with adjust_tp */
        if (!tp->traffic_class || tp->traffic_class == ATM_ANYCLASS)
                return 0;
        if (tp->traffic_class != ATM_UBR && !tp->min_pcr && !tp->pcr &&
            !tp->max_pcr)
                return -EINVAL;
        if (tp->min_pcr == ATM_MAX_PCR)
                return -EINVAL;
        if (tp->min_pcr && tp->max_pcr && tp->max_pcr != ATM_MAX_PCR &&
            tp->min_pcr > tp->max_pcr)
                return -EINVAL;
        /*
         * We allow pcr to be outside [min_pcr,max_pcr], because later
         * adjustment may still push it in the valid range.
         */
        return 0;
}

static int check_qos(const struct atm_qos *qos)
{
        int error;

        if (!qos->txtp.traffic_class && !qos->rxtp.traffic_class)
                return -EINVAL;
        if (qos->txtp.traffic_class != qos->rxtp.traffic_class &&
            qos->txtp.traffic_class && qos->rxtp.traffic_class &&
            qos->txtp.traffic_class != ATM_ANYCLASS &&
            qos->rxtp.traffic_class != ATM_ANYCLASS)
                return -EINVAL;
        error = check_tp(&qos->txtp);
        if (error)
                return error;
        return check_tp(&qos->rxtp);
}

int vcc_setsockopt(struct socket *sock, int level, int optname,
                   sockptr_t optval, unsigned int optlen)
{
        struct atm_vcc *vcc;
        unsigned long value;
        int error;

        if (__SO_LEVEL_MATCH(optname, level) && optlen != __SO_SIZE(optname))
                return -EINVAL;

        vcc = ATM_SD(sock);
        switch (optname) {
        case SO_ATMQOS:
        {
                struct atm_qos qos;

                if (copy_from_sockptr(&qos, optval, sizeof(qos)))
                        return -EFAULT;
                error = check_qos(&qos);
                if (error)
                        return error;
                if (sock->state == SS_CONNECTED)
                        return atm_change_qos(vcc, &qos);
                if (sock->state != SS_UNCONNECTED)
                        return -EBADFD;
                vcc->qos = qos;
                set_bit(ATM_VF_HASQOS, &vcc->flags);
                return 0;
        }
        case SO_SETCLP:
                if (copy_from_sockptr(&value, optval, sizeof(value)))
                        return -EFAULT;
                if (value)
                        vcc->atm_options |= ATM_ATMOPT_CLP;
                else
                        vcc->atm_options &= ~ATM_ATMOPT_CLP;
                return 0;
        default:
                return -EINVAL;
        }
}

int vcc_getsockopt(struct socket *sock, int level, int optname,
                   char __user *optval, int __user *optlen)
{
        struct atm_vcc *vcc;
        int len;

        if (get_user(len, optlen))
                return -EFAULT;
        if (__SO_LEVEL_MATCH(optname, level) && len != __SO_SIZE(optname))
                return -EINVAL;

        vcc = ATM_SD(sock);
        switch (optname) {
        case SO_ATMQOS:
                if (!test_bit(ATM_VF_HASQOS, &vcc->flags))
                        return -EINVAL;
                return copy_to_user(optval, &vcc->qos, sizeof(vcc->qos))
                        ? -EFAULT : 0;
        case SO_SETCLP:
                return put_user(vcc->atm_options & ATM_ATMOPT_CLP ? 1 : 0,
                                (unsigned long __user *)optval) ? -EFAULT : 0;
        case SO_ATMPVC:
        {
                struct sockaddr_atmpvc pvc;

                if (!vcc->dev || !test_bit(ATM_VF_ADDR, &vcc->flags))
                        return -ENOTCONN;
                memset(&pvc, 0, sizeof(pvc));
                pvc.sap_family = AF_ATMPVC;
                pvc.sap_addr.itf = vcc->dev->number;
                pvc.sap_addr.vpi = vcc->vpi;
                pvc.sap_addr.vci = vcc->vci;
                return copy_to_user(optval, &pvc, sizeof(pvc)) ? -EFAULT : 0;
        }
        default:
                return -EINVAL;
        }
}

int register_atmdevice_notifier(struct notifier_block *nb)
{
        return atomic_notifier_chain_register(&atm_dev_notify_chain, nb);
}
EXPORT_SYMBOL_GPL(register_atmdevice_notifier);

void unregister_atmdevice_notifier(struct notifier_block *nb)
{
        atomic_notifier_chain_unregister(&atm_dev_notify_chain, nb);
}
EXPORT_SYMBOL_GPL(unregister_atmdevice_notifier);

static int __init atm_init(void)
{
        int error;

        error = proto_register(&vcc_proto, 0);
        if (error < 0)
                goto out;
        error = atmpvc_init();
        if (error < 0) {
                pr_err("atmpvc_init() failed with %d\n", error);
                goto out_unregister_vcc_proto;
        }
        error = atmsvc_init();
        if (error < 0) {
                pr_err("atmsvc_init() failed with %d\n", error);
                goto out_atmpvc_exit;
        }
        error = atm_proc_init();
        if (error < 0) {
                pr_err("atm_proc_init() failed with %d\n", error);
                goto out_atmsvc_exit;
        }
        error = atm_sysfs_init();
        if (error < 0) {
                pr_err("atm_sysfs_init() failed with %d\n", error);
                goto out_atmproc_exit;
        }
out:
        return error;
out_atmproc_exit:
        atm_proc_exit();
out_atmsvc_exit:
        atmsvc_exit();
out_atmpvc_exit:
        atmpvc_exit();
out_unregister_vcc_proto:
        proto_unregister(&vcc_proto);
        goto out;
}

static void __exit atm_exit(void)
{
        atm_proc_exit();
        atm_sysfs_exit();
        atmsvc_exit();
        atmpvc_exit();
        proto_unregister(&vcc_proto);
}

subsys_initcall(atm_init);

module_exit(atm_exit);

MODULE_DESCRIPTION("Asynchronous Transfer Mode (ATM) networking core");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_ATMPVC);
MODULE_ALIAS_NETPROTO(PF_ATMSVC);
Linux
