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root/net/atm/resources.c

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DEFINITIONS

This source file includes following definitions.
  1. __alloc_atm_dev
  2. __atm_dev_lookup
  3. atm_dev_lookup
  4. atm_dev_register
  5. atm_dev_deregister
  6. copy_aal_stats
  7. subtract_aal_stats
  8. fetch_stats
  9. atm_dev_ioctl
  10. dev_get_idx
  11. atm_dev_seq_start
  12. atm_dev_seq_stop
  13. atm_dev_seq_next

/* net/atm/resources.c - Statically allocated resources */

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

/* Fixes
 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 * 2002/01 - don't free the whole struct sock on sk->destruct time,
 *           use the default destruct function initialized by sock_init_data */


#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/atmdev.h>
#include <linux/sonet.h>
#include <linux/kernel.h> /* for barrier */
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/capability.h>
#include <linux/delay.h>
#include <linux/mutex.h>

#include <net/sock.h>    /* for struct sock */

#include "common.h"
#include "resources.h"
#include "addr.h"


LIST_HEAD(atm_devs);
DEFINE_MUTEX(atm_dev_mutex);

static struct atm_dev *__alloc_atm_dev(const char *type)
{
        struct atm_dev *dev;

        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
        if (!dev)
                return NULL;
        dev->type = type;
        dev->signal = ATM_PHY_SIG_UNKNOWN;
        dev->link_rate = ATM_OC3_PCR;
        spin_lock_init(&dev->lock);
        INIT_LIST_HEAD(&dev->local);
        INIT_LIST_HEAD(&dev->lecs);

        return dev;
}

static struct atm_dev *__atm_dev_lookup(int number)
{
        struct atm_dev *dev;
        struct list_head *p;

        list_for_each(p, &atm_devs) {
                dev = list_entry(p, struct atm_dev, dev_list);
                if (dev->number == number) {
                        atm_dev_hold(dev);
                        return dev;
                }
        }
        return NULL;
}

struct atm_dev *atm_dev_lookup(int number)
{
        struct atm_dev *dev;

        mutex_lock(&atm_dev_mutex);
        dev = __atm_dev_lookup(number);
        mutex_unlock(&atm_dev_mutex);
        return dev;
}


struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
                                 int number, unsigned long *flags)
{
        struct atm_dev *dev, *inuse;

        dev = __alloc_atm_dev(type);
        if (!dev) {
                printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
                    type);
                return NULL;
        }
        mutex_lock(&atm_dev_mutex);
        if (number != -1) {
                if ((inuse = __atm_dev_lookup(number))) {
                        atm_dev_put(inuse);
                        mutex_unlock(&atm_dev_mutex);
                        kfree(dev);
                        return NULL;
                }
                dev->number = number;
        } else {
                dev->number = 0;
                while ((inuse = __atm_dev_lookup(dev->number))) {
                        atm_dev_put(inuse);
                        dev->number++;
                }
        }

        dev->ops = ops;
        if (flags)
                dev->flags = *flags;
        else
                memset(&dev->flags, 0, sizeof(dev->flags));
        memset(&dev->stats, 0, sizeof(dev->stats));
        atomic_set(&dev->refcnt, 1);

        if (atm_proc_dev_register(dev) < 0) {
                printk(KERN_ERR "atm_dev_register: "
                       "atm_proc_dev_register failed for dev %s\n",
                       type);
                goto out_fail;
        }

        if (atm_register_sysfs(dev) < 0) {
                printk(KERN_ERR "atm_dev_register: "
                       "atm_register_sysfs failed for dev %s\n",
                       type);
                atm_proc_dev_deregister(dev);
                goto out_fail;
        }

        list_add_tail(&dev->dev_list, &atm_devs);

out:
        mutex_unlock(&atm_dev_mutex);
        return dev;

out_fail:
        kfree(dev);
        dev = NULL;
        goto out;
}


void atm_dev_deregister(struct atm_dev *dev)
{
        BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
        set_bit(ATM_DF_REMOVED, &dev->flags);

        /*
         * if we remove current device from atm_devs list, new device
         * with same number can appear, such we need deregister proc,
         * release async all vccs and remove them from vccs list too
         */
        mutex_lock(&atm_dev_mutex);
        list_del(&dev->dev_list);
        mutex_unlock(&atm_dev_mutex);

        atm_dev_release_vccs(dev);
        atm_unregister_sysfs(dev);
        atm_proc_dev_deregister(dev);

        atm_dev_put(dev);
}


static void copy_aal_stats(struct k_atm_aal_stats *from,
    struct atm_aal_stats *to)
{
#define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
        __AAL_STAT_ITEMS
#undef __HANDLE_ITEM
}


static void subtract_aal_stats(struct k_atm_aal_stats *from,
    struct atm_aal_stats *to)
{
#define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
        __AAL_STAT_ITEMS
#undef __HANDLE_ITEM
}


static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
{
        struct atm_dev_stats tmp;
        int error = 0;

        copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
        copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
        copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
        if (arg)
                error = copy_to_user(arg, &tmp, sizeof(tmp));
        if (zero && !error) {
                subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
                subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
                subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
        }
        return error ? -EFAULT : 0;
}


int atm_dev_ioctl(unsigned int cmd, void __user *arg)
{
        void __user *buf;
        int error, len, number, size = 0;
        struct atm_dev *dev;
        struct list_head *p;
        int *tmp_buf, *tmp_p;
        struct atm_iobuf __user *iobuf = arg;
        struct atmif_sioc __user *sioc = arg;
        switch (cmd) {
                case ATM_GETNAMES:
                        if (get_user(buf, &iobuf->buffer))
                                return -EFAULT;
                        if (get_user(len, &iobuf->length))
                                return -EFAULT;
                        mutex_lock(&atm_dev_mutex);
                        list_for_each(p, &atm_devs)
                                size += sizeof(int);
                        if (size > len) {
                                mutex_unlock(&atm_dev_mutex);
                                return -E2BIG;
                        }
                        tmp_buf = kmalloc(size, GFP_ATOMIC);
                        if (!tmp_buf) {
                                mutex_unlock(&atm_dev_mutex);
                                return -ENOMEM;
                        }
                        tmp_p = tmp_buf;
                        list_for_each(p, &atm_devs) {
                                dev = list_entry(p, struct atm_dev, dev_list);
                                *tmp_p++ = dev->number;
                        }
                        mutex_unlock(&atm_dev_mutex);
                        error = ((copy_to_user(buf, tmp_buf, size)) ||
                                        put_user(size, &iobuf->length))
                                                ? -EFAULT : 0;
                        kfree(tmp_buf);
                        return error;
                default:
                        break;
        }

        if (get_user(buf, &sioc->arg))
                return -EFAULT;
        if (get_user(len, &sioc->length))
                return -EFAULT;
        if (get_user(number, &sioc->number))
                return -EFAULT;

        if (!(dev = try_then_request_module(atm_dev_lookup(number),
                                            "atm-device-%d", number)))
                return -ENODEV;

        switch (cmd) {
                case ATM_GETTYPE:
                        size = strlen(dev->type) + 1;
                        if (copy_to_user(buf, dev->type, size)) {
                                error = -EFAULT;
                                goto done;
                        }
                        break;
                case ATM_GETESI:
                        size = ESI_LEN;
                        if (copy_to_user(buf, dev->esi, size)) {
                                error = -EFAULT;
                                goto done;
                        }
                        break;
                case ATM_SETESI:
                        {
                                int i;

                                for (i = 0; i < ESI_LEN; i++)
                                        if (dev->esi[i]) {
                                                error = -EEXIST;
                                                goto done;
                                        }
                        }
                        /* fall through */
                case ATM_SETESIF:
                        {
                                unsigned char esi[ESI_LEN];

                                if (!capable(CAP_NET_ADMIN)) {
                                        error = -EPERM;
                                        goto done;
                                }
                                if (copy_from_user(esi, buf, ESI_LEN)) {
                                        error = -EFAULT;
                                        goto done;
                                }
                                memcpy(dev->esi, esi, ESI_LEN);
                                error =  ESI_LEN;
                                goto done;
                        }
                case ATM_GETSTATZ:
                        if (!capable(CAP_NET_ADMIN)) {
                                error = -EPERM;
                                goto done;
                        }
                        /* fall through */
                case ATM_GETSTAT:
                        size = sizeof(struct atm_dev_stats);
                        error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
                        if (error)
                                goto done;
                        break;
                case ATM_GETCIRANGE:
                        size = sizeof(struct atm_cirange);
                        if (copy_to_user(buf, &dev->ci_range, size)) {
                                error = -EFAULT;
                                goto done;
                        }
                        break;
                case ATM_GETLINKRATE:
                        size = sizeof(int);
                        if (copy_to_user(buf, &dev->link_rate, size)) {
                                error = -EFAULT;
                                goto done;
                        }
                        break;
                case ATM_RSTADDR:
                        if (!capable(CAP_NET_ADMIN)) {
                                error = -EPERM;
                                goto done;
                        }
                        atm_reset_addr(dev, ATM_ADDR_LOCAL);
                        break;
                case ATM_ADDADDR:
                case ATM_DELADDR:
                case ATM_ADDLECSADDR:
                case ATM_DELLECSADDR:
                        if (!capable(CAP_NET_ADMIN)) {
                                error = -EPERM;
                                goto done;
                        }
                        {
                                struct sockaddr_atmsvc addr;

                                if (copy_from_user(&addr, buf, sizeof(addr))) {
                                        error = -EFAULT;
                                        goto done;
                                }
                                if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
                                        error = atm_add_addr(dev, &addr,
                                                             (cmd == ATM_ADDADDR ?
                                                              ATM_ADDR_LOCAL : ATM_ADDR_LECS));
                                else
                                        error = atm_del_addr(dev, &addr,
                                                             (cmd == ATM_DELADDR ?
                                                              ATM_ADDR_LOCAL : ATM_ADDR_LECS));
                                goto done;
                        }
                case ATM_GETADDR:
                case ATM_GETLECSADDR:
                        error = atm_get_addr(dev, buf, len,
                                             (cmd == ATM_GETADDR ?
                                              ATM_ADDR_LOCAL : ATM_ADDR_LECS));
                        if (error < 0)
                                goto done;
                        size = error;
                        /* may return 0, but later on size == 0 means "don't
                           write the length" */
                        error = put_user(size, &sioc->length)
                                ? -EFAULT : 0;
                        goto done;
                case ATM_SETLOOP:
                        if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
                            __ATM_LM_XTLOC((int) (unsigned long) buf) >
                            __ATM_LM_XTRMT((int) (unsigned long) buf)) {
                                error = -EINVAL;
                                goto done;
                        }
                        /* fall through */
                case ATM_SETCIRANGE:
                case SONET_GETSTATZ:
                case SONET_SETDIAG:
                case SONET_CLRDIAG:
                case SONET_SETFRAMING:
                        if (!capable(CAP_NET_ADMIN)) {
                                error = -EPERM;
                                goto done;
                        }
                        /* fall through */
                default:
                        if (!dev->ops->ioctl) {
                                error = -EINVAL;
                                goto done;
                        }
                        size = dev->ops->ioctl(dev, cmd, buf);
                        if (size < 0) {
                                error = (size == -ENOIOCTLCMD ? -EINVAL : size);
                                goto done;
                        }
        }

        if (size)
                error = put_user(size, &sioc->length)
                        ? -EFAULT : 0;
        else
                error = 0;
done:
        atm_dev_put(dev);
        return error;
}

static __inline__ void *dev_get_idx(loff_t left)
{
        struct list_head *p;

        list_for_each(p, &atm_devs) {
                if (!--left)
                        break;
        }
        return (p != &atm_devs) ? p : NULL;
}

void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
{
        mutex_lock(&atm_dev_mutex);
        return *pos ? dev_get_idx(*pos) : SEQ_START_TOKEN;
}

void atm_dev_seq_stop(struct seq_file *seq, void *v)
{
        mutex_unlock(&atm_dev_mutex);
}

void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
        ++*pos;
        v = (v == SEQ_START_TOKEN)
                ? atm_devs.next : ((struct list_head *)v)->next;
        return (v == &atm_devs) ? NULL : v;
}


EXPORT_SYMBOL(atm_dev_register);
EXPORT_SYMBOL(atm_dev_deregister);
EXPORT_SYMBOL(atm_dev_lookup);

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