linux/net/atm/resources.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0
   2/* net/atm/resources.c - Statically allocated resources */
   3
   4/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   5
   6/* Fixes
   7 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   8 * 2002/01 - don't free the whole struct sock on sk->destruct time,
   9 *           use the default destruct function initialized by sock_init_data */
  10
  11#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
  12
  13#include <linux/ctype.h>
  14#include <linux/string.h>
  15#include <linux/atmdev.h>
  16#include <linux/sonet.h>
  17#include <linux/kernel.h> /* for barrier */
  18#include <linux/module.h>
  19#include <linux/bitops.h>
  20#include <linux/capability.h>
  21#include <linux/delay.h>
  22#include <linux/mutex.h>
  23#include <linux/slab.h>
  24
  25#include <net/sock.h>    /* for struct sock */
  26
  27#include "common.h"
  28#include "resources.h"
  29#include "addr.h"
  30
  31
  32LIST_HEAD(atm_devs);
  33DEFINE_MUTEX(atm_dev_mutex);
  34
  35static struct atm_dev *__alloc_atm_dev(const char *type)
  36{
  37        struct atm_dev *dev;
  38
  39        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  40        if (!dev)
  41                return NULL;
  42        dev->type = type;
  43        dev->signal = ATM_PHY_SIG_UNKNOWN;
  44        dev->link_rate = ATM_OC3_PCR;
  45        spin_lock_init(&dev->lock);
  46        INIT_LIST_HEAD(&dev->local);
  47        INIT_LIST_HEAD(&dev->lecs);
  48
  49        return dev;
  50}
  51
  52static struct atm_dev *__atm_dev_lookup(int number)
  53{
  54        struct atm_dev *dev;
  55        struct list_head *p;
  56
  57        list_for_each(p, &atm_devs) {
  58                dev = list_entry(p, struct atm_dev, dev_list);
  59                if (dev->number == number) {
  60                        atm_dev_hold(dev);
  61                        return dev;
  62                }
  63        }
  64        return NULL;
  65}
  66
  67struct atm_dev *atm_dev_lookup(int number)
  68{
  69        struct atm_dev *dev;
  70
  71        mutex_lock(&atm_dev_mutex);
  72        dev = __atm_dev_lookup(number);
  73        mutex_unlock(&atm_dev_mutex);
  74        return dev;
  75}
  76EXPORT_SYMBOL(atm_dev_lookup);
  77
  78struct atm_dev *atm_dev_register(const char *type, struct device *parent,
  79                                 const struct atmdev_ops *ops, int number,
  80                                 unsigned long *flags)
  81{
  82        struct atm_dev *dev, *inuse;
  83
  84        dev = __alloc_atm_dev(type);
  85        if (!dev) {
  86                pr_err("no space for dev %s\n", type);
  87                return NULL;
  88        }
  89        mutex_lock(&atm_dev_mutex);
  90        if (number != -1) {
  91                inuse = __atm_dev_lookup(number);
  92                if (inuse) {
  93                        atm_dev_put(inuse);
  94                        mutex_unlock(&atm_dev_mutex);
  95                        kfree(dev);
  96                        return NULL;
  97                }
  98                dev->number = number;
  99        } else {
 100                dev->number = 0;
 101                while ((inuse = __atm_dev_lookup(dev->number))) {
 102                        atm_dev_put(inuse);
 103                        dev->number++;
 104                }
 105        }
 106
 107        dev->ops = ops;
 108        if (flags)
 109                dev->flags = *flags;
 110        else
 111                memset(&dev->flags, 0, sizeof(dev->flags));
 112        memset(&dev->stats, 0, sizeof(dev->stats));
 113        refcount_set(&dev->refcnt, 1);
 114
 115        if (atm_proc_dev_register(dev) < 0) {
 116                pr_err("atm_proc_dev_register failed for dev %s\n", type);
 117                goto out_fail;
 118        }
 119
 120        if (atm_register_sysfs(dev, parent) < 0) {
 121                pr_err("atm_register_sysfs failed for dev %s\n", type);
 122                atm_proc_dev_deregister(dev);
 123                goto out_fail;
 124        }
 125
 126        list_add_tail(&dev->dev_list, &atm_devs);
 127
 128out:
 129        mutex_unlock(&atm_dev_mutex);
 130        return dev;
 131
 132out_fail:
 133        kfree(dev);
 134        dev = NULL;
 135        goto out;
 136}
 137EXPORT_SYMBOL(atm_dev_register);
 138
 139void atm_dev_deregister(struct atm_dev *dev)
 140{
 141        BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
 142        set_bit(ATM_DF_REMOVED, &dev->flags);
 143
 144        /*
 145         * if we remove current device from atm_devs list, new device
 146         * with same number can appear, such we need deregister proc,
 147         * release async all vccs and remove them from vccs list too
 148         */
 149        mutex_lock(&atm_dev_mutex);
 150        list_del(&dev->dev_list);
 151        mutex_unlock(&atm_dev_mutex);
 152
 153        atm_dev_release_vccs(dev);
 154        atm_unregister_sysfs(dev);
 155        atm_proc_dev_deregister(dev);
 156
 157        atm_dev_put(dev);
 158}
 159EXPORT_SYMBOL(atm_dev_deregister);
 160
 161static void copy_aal_stats(struct k_atm_aal_stats *from,
 162    struct atm_aal_stats *to)
 163{
 164#define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
 165        __AAL_STAT_ITEMS
 166#undef __HANDLE_ITEM
 167}
 168
 169static void subtract_aal_stats(struct k_atm_aal_stats *from,
 170    struct atm_aal_stats *to)
 171{
 172#define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
 173        __AAL_STAT_ITEMS
 174#undef __HANDLE_ITEM
 175}
 176
 177static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg,
 178                       int zero)
 179{
 180        struct atm_dev_stats tmp;
 181        int error = 0;
 182
 183        copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
 184        copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
 185        copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
 186        if (arg)
 187                error = copy_to_user(arg, &tmp, sizeof(tmp));
 188        if (zero && !error) {
 189                subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
 190                subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
 191                subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
 192        }
 193        return error ? -EFAULT : 0;
 194}
 195
 196int atm_getnames(void __user *buf, int __user *iobuf_len)
 197{
 198        int error, len, size = 0;
 199        struct atm_dev *dev;
 200        struct list_head *p;
 201        int *tmp_buf, *tmp_p;
 202
 203        if (get_user(len, iobuf_len))
 204                return -EFAULT;
 205        mutex_lock(&atm_dev_mutex);
 206        list_for_each(p, &atm_devs)
 207                size += sizeof(int);
 208        if (size > len) {
 209                mutex_unlock(&atm_dev_mutex);
 210                return -E2BIG;
 211        }
 212        tmp_buf = kmalloc(size, GFP_ATOMIC);
 213        if (!tmp_buf) {
 214                mutex_unlock(&atm_dev_mutex);
 215                return -ENOMEM;
 216        }
 217        tmp_p = tmp_buf;
 218        list_for_each(p, &atm_devs) {
 219                dev = list_entry(p, struct atm_dev, dev_list);
 220                *tmp_p++ = dev->number;
 221        }
 222        mutex_unlock(&atm_dev_mutex);
 223        error = ((copy_to_user(buf, tmp_buf, size)) ||
 224                 put_user(size, iobuf_len))
 225                ? -EFAULT : 0;
 226        kfree(tmp_buf);
 227        return error;
 228}
 229
 230int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
 231                  int number, int compat)
 232{
 233        int error, len, size = 0;
 234        struct atm_dev *dev;
 235
 236        if (get_user(len, sioc_len))
 237                return -EFAULT;
 238
 239        dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
 240                                      number);
 241        if (!dev)
 242                return -ENODEV;
 243
 244        switch (cmd) {
 245        case ATM_GETTYPE:
 246                size = strlen(dev->type) + 1;
 247                if (copy_to_user(buf, dev->type, size)) {
 248                        error = -EFAULT;
 249                        goto done;
 250                }
 251                break;
 252        case ATM_GETESI:
 253                size = ESI_LEN;
 254                if (copy_to_user(buf, dev->esi, size)) {
 255                        error = -EFAULT;
 256                        goto done;
 257                }
 258                break;
 259        case ATM_SETESI:
 260        {
 261                int i;
 262
 263                for (i = 0; i < ESI_LEN; i++)
 264                        if (dev->esi[i]) {
 265                                error = -EEXIST;
 266                                goto done;
 267                        }
 268        }
 269                fallthrough;
 270        case ATM_SETESIF:
 271        {
 272                unsigned char esi[ESI_LEN];
 273
 274                if (!capable(CAP_NET_ADMIN)) {
 275                        error = -EPERM;
 276                        goto done;
 277                }
 278                if (copy_from_user(esi, buf, ESI_LEN)) {
 279                        error = -EFAULT;
 280                        goto done;
 281                }
 282                memcpy(dev->esi, esi, ESI_LEN);
 283                error =  ESI_LEN;
 284                goto done;
 285        }
 286        case ATM_GETSTATZ:
 287                if (!capable(CAP_NET_ADMIN)) {
 288                        error = -EPERM;
 289                        goto done;
 290                }
 291                fallthrough;
 292        case ATM_GETSTAT:
 293                size = sizeof(struct atm_dev_stats);
 294                error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 295                if (error)
 296                        goto done;
 297                break;
 298        case ATM_GETCIRANGE:
 299                size = sizeof(struct atm_cirange);
 300                if (copy_to_user(buf, &dev->ci_range, size)) {
 301                        error = -EFAULT;
 302                        goto done;
 303                }
 304                break;
 305        case ATM_GETLINKRATE:
 306                size = sizeof(int);
 307                if (copy_to_user(buf, &dev->link_rate, size)) {
 308                        error = -EFAULT;
 309                        goto done;
 310                }
 311                break;
 312        case ATM_RSTADDR:
 313                if (!capable(CAP_NET_ADMIN)) {
 314                        error = -EPERM;
 315                        goto done;
 316                }
 317                atm_reset_addr(dev, ATM_ADDR_LOCAL);
 318                break;
 319        case ATM_ADDADDR:
 320        case ATM_DELADDR:
 321        case ATM_ADDLECSADDR:
 322        case ATM_DELLECSADDR:
 323        {
 324                struct sockaddr_atmsvc addr;
 325
 326                if (!capable(CAP_NET_ADMIN)) {
 327                        error = -EPERM;
 328                        goto done;
 329                }
 330
 331                if (copy_from_user(&addr, buf, sizeof(addr))) {
 332                        error = -EFAULT;
 333                        goto done;
 334                }
 335                if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
 336                        error = atm_add_addr(dev, &addr,
 337                                             (cmd == ATM_ADDADDR ?
 338                                              ATM_ADDR_LOCAL : ATM_ADDR_LECS));
 339                else
 340                        error = atm_del_addr(dev, &addr,
 341                                             (cmd == ATM_DELADDR ?
 342                                              ATM_ADDR_LOCAL : ATM_ADDR_LECS));
 343                goto done;
 344        }
 345        case ATM_GETADDR:
 346        case ATM_GETLECSADDR:
 347                error = atm_get_addr(dev, buf, len,
 348                                     (cmd == ATM_GETADDR ?
 349                                      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
 350                if (error < 0)
 351                        goto done;
 352                size = error;
 353                /* may return 0, but later on size == 0 means "don't
 354                   write the length" */
 355                error = put_user(size, sioc_len) ? -EFAULT : 0;
 356                goto done;
 357        case ATM_SETLOOP:
 358                if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
 359                    __ATM_LM_XTLOC((int) (unsigned long) buf) >
 360                    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
 361                        error = -EINVAL;
 362                        goto done;
 363                }
 364                fallthrough;
 365        case ATM_SETCIRANGE:
 366        case SONET_GETSTATZ:
 367        case SONET_SETDIAG:
 368        case SONET_CLRDIAG:
 369        case SONET_SETFRAMING:
 370                if (!capable(CAP_NET_ADMIN)) {
 371                        error = -EPERM;
 372                        goto done;
 373                }
 374                fallthrough;
 375        default:
 376                if (IS_ENABLED(CONFIG_COMPAT) && compat) {
 377#ifdef CONFIG_COMPAT
 378                        if (!dev->ops->compat_ioctl) {
 379                                error = -EINVAL;
 380                                goto done;
 381                        }
 382                        size = dev->ops->compat_ioctl(dev, cmd, buf);
 383#endif
 384                } else {
 385                        if (!dev->ops->ioctl) {
 386                                error = -EINVAL;
 387                                goto done;
 388                        }
 389                        size = dev->ops->ioctl(dev, cmd, buf);
 390                }
 391                if (size < 0) {
 392                        error = (size == -ENOIOCTLCMD ? -ENOTTY : size);
 393                        goto done;
 394                }
 395        }
 396
 397        if (size)
 398                error = put_user(size, sioc_len) ? -EFAULT : 0;
 399        else
 400                error = 0;
 401done:
 402        atm_dev_put(dev);
 403        return error;
 404}
 405
 406void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
 407{
 408        mutex_lock(&atm_dev_mutex);
 409        return seq_list_start_head(&atm_devs, *pos);
 410}
 411
 412void atm_dev_seq_stop(struct seq_file *seq, void *v)
 413{
 414        mutex_unlock(&atm_dev_mutex);
 415}
 416
 417void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 418{
 419        return seq_list_next(v, &atm_devs, pos);
 420}
 421