net/atm/resources.c

   1 /* net/atm/resources.c - Statically allocated resources */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5 /* Fixes
   6  * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   7  * 2002/01 - don't free the whole struct sock on sk->destruct time,
   8  *           use the default destruct function initialized by sock_init_data */
   9
  10
  11 #include <linux/config.h>
  12 #include <linux/ctype.h>
  13 #include <linux/string.h>
  14 #include <linux/atmdev.h>
  15 #include <linux/sonet.h>
  16 #include <linux/kernel.h> /* for barrier */
  17 #include <linux/module.h>
  18 #include <linux/bitops.h>
  19 #include <net/sock.h>    /* for struct sock */
  20
  21 #include "common.h"
  22 #include "resources.h"
  23 #include "addr.h"
  24
  25
  26 LIST_HEAD(atm_devs);
  27 spinlock_t atm_dev_lock = SPIN_LOCK_UNLOCKED;
  28
  29 static struct atm_dev *__alloc_atm_dev(const char *type)
  30 {
  31         struct atm_dev *dev;
  32
  33         dev = kmalloc(sizeof(*dev), GFP_KERNEL);
  34         if (!dev)
  35                 return NULL;
  36         memset(dev, 0, sizeof(*dev));
  37         dev->type = type;
  38         dev->signal = ATM_PHY_SIG_UNKNOWN;
  39         dev->link_rate = ATM_OC3_PCR;
  40         spin_lock_init(&dev->lock);
  41
  42         return dev;
  43 }
  44
  45 static void __free_atm_dev(struct atm_dev *dev)
  46 {
  47         kfree(dev);
  48 }
  49
  50 static struct atm_dev *__atm_dev_lookup(int number)
  51 {
  52         struct atm_dev *dev;
  53         struct list_head *p;
  54
  55         list_for_each(p, &atm_devs) {
  56                 dev = list_entry(p, struct atm_dev, dev_list);
  57                 if ((dev->ops) && (dev->number == number)) {
  58                         atm_dev_hold(dev);
  59                         return dev;
  60                 }
  61         }
  62         return NULL;
  63 }
  64
  65 struct atm_dev *atm_dev_lookup(int number)
  66 {
  67         struct atm_dev *dev;
  68
  69         spin_lock(&atm_dev_lock);
  70         dev = __atm_dev_lookup(number);
  71         spin_unlock(&atm_dev_lock);
  72         return dev;
  73 }
  74
  75 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
  76                                  int number, unsigned long *flags)
  77 {
  78         struct atm_dev *dev, *inuse;
  79
  80         dev = __alloc_atm_dev(type);
  81         if (!dev) {
  82                 printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
  83                     type);
  84                 return NULL;
  85         }
  86         spin_lock(&atm_dev_lock);
  87         if (number != -1) {
  88                 if ((inuse = __atm_dev_lookup(number))) {
  89                         atm_dev_put(inuse);
  90                         spin_unlock(&atm_dev_lock);
  91                         __free_atm_dev(dev);
  92                         return NULL;
  93                 }
  94                 dev->number = number;
  95         } else {
  96                 dev->number = 0;
  97                 while ((inuse = __atm_dev_lookup(dev->number))) {
  98                         atm_dev_put(inuse);
  99                         dev->number++;
 100                 }
 101         }
 102
 103         dev->ops = ops;
 104         if (flags)
 105                 dev->flags = *flags;
 106         else
 107                 memset(&dev->flags, 0, sizeof(dev->flags));
 108         memset(&dev->stats, 0, sizeof(dev->stats));
 109         atomic_set(&dev->refcnt, 1);
 110         list_add_tail(&dev->dev_list, &atm_devs);
 111         spin_unlock(&atm_dev_lock);
 112
 113         if (atm_proc_dev_register(dev) < 0) {
 114                 printk(KERN_ERR "atm_dev_register: "
 115                        "atm_proc_dev_register failed for dev %s\n",
 116                        type);
 117                 spin_lock(&atm_dev_lock);
 118                 list_del(&dev->dev_list);
 119                 spin_unlock(&atm_dev_lock);
 120                 __free_atm_dev(dev);
 121                 return NULL;
 122         }
 123
 124         return dev;
 125 }
 126
 127
 128 void atm_dev_deregister(struct atm_dev *dev)
 129 {
 130         unsigned long warning_time;
 131
 132         atm_proc_dev_deregister(dev);
 133
 134         spin_lock(&atm_dev_lock);
 135         list_del(&dev->dev_list);
 136         spin_unlock(&atm_dev_lock);
 137
 138         warning_time = jiffies;
 139         while (atomic_read(&dev->refcnt) != 1) {
 140                 current->state = TASK_INTERRUPTIBLE;
 141                 schedule_timeout(HZ / 4);
 142                 if ((jiffies - warning_time) > 10 * HZ) {
 143                         printk(KERN_EMERG "atm_dev_deregister: waiting for "
 144                                "dev %d to become free. Usage count = %d\n",
 145                                dev->number, atomic_read(&dev->refcnt));
 146                         warning_time = jiffies;
 147                 }
 148         }
 149
 150         __free_atm_dev(dev);
 151 }
 152
 153 void shutdown_atm_dev(struct atm_dev *dev)
 154 {
 155         if (atomic_read(&dev->refcnt) > 1) {
 156                 set_bit(ATM_DF_CLOSE, &dev->flags);
 157                 return;
 158         }
 159         if (dev->ops->dev_close)
 160                 dev->ops->dev_close(dev);
 161         atm_dev_deregister(dev);
 162 }
 163
 164
 165 static void copy_aal_stats(struct k_atm_aal_stats *from,
 166     struct atm_aal_stats *to)
 167 {
 168 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
 169         __AAL_STAT_ITEMS
 170 #undef __HANDLE_ITEM
 171 }
 172
 173
 174 static void subtract_aal_stats(struct k_atm_aal_stats *from,
 175     struct atm_aal_stats *to)
 176 {
 177 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
 178         __AAL_STAT_ITEMS
 179 #undef __HANDLE_ITEM
 180 }
 181
 182
 183 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats *arg, int zero)
 184 {
 185         struct atm_dev_stats tmp;
 186         int error = 0;
 187
 188         copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
 189         copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
 190         copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
 191         if (arg)
 192                 error = copy_to_user(arg, &tmp, sizeof(tmp));
 193         if (zero && !error) {
 194                 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
 195                 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
 196                 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
 197         }
 198         return error ? -EFAULT : 0;
 199 }
 200
 201
 202 int atm_dev_ioctl(unsigned int cmd, unsigned long arg)
 203 {
 204         void *buf;
 205         int error, len, number, size = 0;
 206         struct atm_dev *dev;
 207         struct list_head *p;
 208         int *tmp_buf, *tmp_p;
 209
 210         switch (cmd) {
 211                 case ATM_GETNAMES:
 212                         if (get_user(buf, &((struct atm_iobuf *) arg)->buffer))
 213                                 return -EFAULT;
 214                         if (get_user(len, &((struct atm_iobuf *) arg)->length))
 215                                 return -EFAULT;
 216                         spin_lock(&atm_dev_lock);
 217                         list_for_each(p, &atm_devs)
 218                                 size += sizeof(int);
 219                         if (size > len) {
 220                                 spin_unlock(&atm_dev_lock);
 221                                 return -E2BIG;
 222                         }
 223                         tmp_buf = kmalloc(size, GFP_ATOMIC);
 224                         if (!tmp_buf) {
 225                                 spin_unlock(&atm_dev_lock);
 226                                 return -ENOMEM;
 227                         }
 228                         tmp_p = tmp_buf;
 229                         list_for_each(p, &atm_devs) {
 230                                 dev = list_entry(p, struct atm_dev, dev_list);
 231                                 *tmp_p++ = dev->number;
 232                         }
 233                         spin_unlock(&atm_dev_lock);
 234                         error = ((copy_to_user(buf, tmp_buf, size)) ||
 235                                         put_user(size, &((struct atm_iobuf *) arg)->length))
 236                                                 ? -EFAULT : 0;
 237                         kfree(tmp_buf);
 238                         return error;
 239                 default:
 240                         break;
 241         }
 242
 243         if (get_user(buf, &((struct atmif_sioc *) arg)->arg))
 244                 return -EFAULT;
 245         if (get_user(len, &((struct atmif_sioc *) arg)->length))
 246                 return -EFAULT;
 247         if (get_user(number, &((struct atmif_sioc *) arg)->number))
 248                 return -EFAULT;
 249
 250         if (!(dev = atm_dev_lookup(number)))
 251                 return -ENODEV;
 252
 253         switch (cmd) {
 254                 case ATM_GETTYPE:
 255                         size = strlen(dev->type) + 1;
 256                         if (copy_to_user(buf, dev->type, size)) {
 257                                 error = -EFAULT;
 258                                 goto done;
 259                         }
 260                         break;
 261                 case ATM_GETESI:
 262                         size = ESI_LEN;
 263                         if (copy_to_user(buf, dev->esi, size)) {
 264                                 error = -EFAULT;
 265                                 goto done;
 266                         }
 267                         break;
 268                 case ATM_SETESI:
 269                         {
 270                                 int i;
 271
 272                                 for (i = 0; i < ESI_LEN; i++)
 273                                         if (dev->esi[i]) {
 274                                                 error = -EEXIST;
 275                                                 goto done;
 276                                         }
 277                         }
 278                         /* fall through */
 279                 case ATM_SETESIF:
 280                         {
 281                                 unsigned char esi[ESI_LEN];
 282
 283                                 if (!capable(CAP_NET_ADMIN)) {
 284                                         error = -EPERM;
 285                                         goto done;
 286                                 }
 287                                 if (copy_from_user(esi, buf, ESI_LEN)) {
 288                                         error = -EFAULT;
 289                                         goto done;
 290                                 }
 291                                 memcpy(dev->esi, esi, ESI_LEN);
 292                                 error =  ESI_LEN;
 293                                 goto done;
 294                         }
 295                 case ATM_GETSTATZ:
 296                         if (!capable(CAP_NET_ADMIN)) {
 297                                 error = -EPERM;
 298                                 goto done;
 299                         }
 300                         /* fall through */
 301                 case ATM_GETSTAT:
 302                         size = sizeof(struct atm_dev_stats);
 303                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 304                         if (error)
 305                                 goto done;
 306                         break;
 307                 case ATM_GETCIRANGE:
 308                         size = sizeof(struct atm_cirange);
 309                         if (copy_to_user(buf, &dev->ci_range, size)) {
 310                                 error = -EFAULT;
 311                                 goto done;
 312                         }
 313                         break;
 314                 case ATM_GETLINKRATE:
 315                         size = sizeof(int);
 316                         if (copy_to_user(buf, &dev->link_rate, size)) {
 317                                 error = -EFAULT;
 318                                 goto done;
 319                         }
 320                         break;
 321                 case ATM_RSTADDR:
 322                         if (!capable(CAP_NET_ADMIN)) {
 323                                 error = -EPERM;
 324                                 goto done;
 325                         }
 326                         atm_reset_addr(dev);
 327                         break;
 328                 case ATM_ADDADDR:
 329                 case ATM_DELADDR:
 330                         if (!capable(CAP_NET_ADMIN)) {
 331                                 error = -EPERM;
 332                                 goto done;
 333                         }
 334                         {
 335                                 struct sockaddr_atmsvc addr;
 336
 337                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
 338                                         error = -EFAULT;
 339                                         goto done;
 340                                 }
 341                                 if (cmd == ATM_ADDADDR)
 342                                         error = atm_add_addr(dev, &addr);
 343                                 else
 344                                         error = atm_del_addr(dev, &addr);
 345                                 goto done;
 346                         }
 347                 case ATM_GETADDR:
 348                         error = atm_get_addr(dev, buf, len);
 349                         if (error < 0)
 350                                 goto done;
 351                         size = error;
 352                         /* may return 0, but later on size == 0 means "don't
 353                            write the length" */
 354                         error = put_user(size, &((struct atmif_sioc *) arg)->length)
 355                                 ? -EFAULT : 0;
 356                         goto done;
 357                 case ATM_SETLOOP:
 358                         if (__ATM_LM_XTRMT((int) (long) buf) &&
 359                             __ATM_LM_XTLOC((int) (long) buf) >
 360                             __ATM_LM_XTRMT((int) (long) buf)) {
 361                                 error = -EINVAL;
 362                                 goto done;
 363                         }
 364                         /* fall through */
 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                         /* fall through */
 375                 default:
 376                         if (!dev->ops->ioctl) {
 377                                 error = -EINVAL;
 378                                 goto done;
 379                         }
 380                         size = dev->ops->ioctl(dev, cmd, buf);
 381                         if (size < 0) {
 382                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
 383                                 goto done;
 384                         }
 385         }
 386
 387         if (size)
 388                 error = put_user(size, &((struct atmif_sioc *) arg)->length)
 389                         ? -EFAULT : 0;
 390         else
 391                 error = 0;
 392 done:
 393         atm_dev_put(dev);
 394         return error;
 395 }
 396
 397 static __inline__ void *dev_get_idx(loff_t left)
 398 {
 399         struct list_head *p;
 400
 401         list_for_each(p, &atm_devs) {
 402                 if (!--left)
 403                         break;
 404         }
 405         return (p != &atm_devs) ? p : NULL;
 406 }
 407
 408 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
 409 {
 410         spin_lock(&atm_dev_lock);
 411         return *pos ? dev_get_idx(*pos) : (void *) 1;
 412 }
 413
 414 void atm_dev_seq_stop(struct seq_file *seq, void *v)
 415 {
 416         spin_unlock(&atm_dev_lock);
 417 }
 418
 419 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 420 {
 421         ++*pos;
 422         v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
 423         return (v == &atm_devs) ? NULL : v;
 424 }
 425
 426
 427 EXPORT_SYMBOL(atm_dev_register);
 428 EXPORT_SYMBOL(atm_dev_deregister);
 429 EXPORT_SYMBOL(atm_dev_lookup);
 430 EXPORT_SYMBOL(shutdown_atm_dev);