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 __user *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, void __user *arg)
 203 {
 204         void __user *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         struct atm_iobuf __user *iobuf = arg;
 210         struct atmif_sioc __user *sioc = arg;
 211         switch (cmd) {
 212                 case ATM_GETNAMES:
 213                         if (get_user(buf, &iobuf->buffer))
 214                                 return -EFAULT;
 215                         if (get_user(len, &iobuf->length))
 216                                 return -EFAULT;
 217                         spin_lock(&atm_dev_lock);
 218                         list_for_each(p, &atm_devs)
 219                                 size += sizeof(int);
 220                         if (size > len) {
 221                                 spin_unlock(&atm_dev_lock);
 222                                 return -E2BIG;
 223                         }
 224                         tmp_buf = kmalloc(size, GFP_ATOMIC);
 225                         if (!tmp_buf) {
 226                                 spin_unlock(&atm_dev_lock);
 227                                 return -ENOMEM;
 228                         }
 229                         tmp_p = tmp_buf;
 230                         list_for_each(p, &atm_devs) {
 231                                 dev = list_entry(p, struct atm_dev, dev_list);
 232                                 *tmp_p++ = dev->number;
 233                         }
 234                         spin_unlock(&atm_dev_lock);
 235                         error = ((copy_to_user(buf, tmp_buf, size)) ||
 236                                         put_user(size, &iobuf->length))
 237                                                 ? -EFAULT : 0;
 238                         kfree(tmp_buf);
 239                         return error;
 240                 default:
 241                         break;
 242         }
 243
 244         if (get_user(buf, &sioc->arg))
 245                 return -EFAULT;
 246         if (get_user(len, &sioc->length))
 247                 return -EFAULT;
 248         if (get_user(number, &sioc->number))
 249                 return -EFAULT;
 250
 251         if (!(dev = atm_dev_lookup(number)))
 252                 return -ENODEV;
 253
 254         switch (cmd) {
 255                 case ATM_GETTYPE:
 256                         size = strlen(dev->type) + 1;
 257                         if (copy_to_user(buf, dev->type, size)) {
 258                                 error = -EFAULT;
 259                                 goto done;
 260                         }
 261                         break;
 262                 case ATM_GETESI:
 263                         size = ESI_LEN;
 264                         if (copy_to_user(buf, dev->esi, size)) {
 265                                 error = -EFAULT;
 266                                 goto done;
 267                         }
 268                         break;
 269                 case ATM_SETESI:
 270                         {
 271                                 int i;
 272
 273                                 for (i = 0; i < ESI_LEN; i++)
 274                                         if (dev->esi[i]) {
 275                                                 error = -EEXIST;
 276                                                 goto done;
 277                                         }
 278                         }
 279                         /* fall through */
 280                 case ATM_SETESIF:
 281                         {
 282                                 unsigned char esi[ESI_LEN];
 283
 284                                 if (!capable(CAP_NET_ADMIN)) {
 285                                         error = -EPERM;
 286                                         goto done;
 287                                 }
 288                                 if (copy_from_user(esi, buf, ESI_LEN)) {
 289                                         error = -EFAULT;
 290                                         goto done;
 291                                 }
 292                                 memcpy(dev->esi, esi, ESI_LEN);
 293                                 error =  ESI_LEN;
 294                                 goto done;
 295                         }
 296                 case ATM_GETSTATZ:
 297                         if (!capable(CAP_NET_ADMIN)) {
 298                                 error = -EPERM;
 299                                 goto done;
 300                         }
 301                         /* fall through */
 302                 case ATM_GETSTAT:
 303                         size = sizeof(struct atm_dev_stats);
 304                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 305                         if (error)
 306                                 goto done;
 307                         break;
 308                 case ATM_GETCIRANGE:
 309                         size = sizeof(struct atm_cirange);
 310                         if (copy_to_user(buf, &dev->ci_range, size)) {
 311                                 error = -EFAULT;
 312                                 goto done;
 313                         }
 314                         break;
 315                 case ATM_GETLINKRATE:
 316                         size = sizeof(int);
 317                         if (copy_to_user(buf, &dev->link_rate, size)) {
 318                                 error = -EFAULT;
 319                                 goto done;
 320                         }
 321                         break;
 322                 case ATM_RSTADDR:
 323                         if (!capable(CAP_NET_ADMIN)) {
 324                                 error = -EPERM;
 325                                 goto done;
 326                         }
 327                         atm_reset_addr(dev);
 328                         break;
 329                 case ATM_ADDADDR:
 330                 case ATM_DELADDR:
 331                         if (!capable(CAP_NET_ADMIN)) {
 332                                 error = -EPERM;
 333                                 goto done;
 334                         }
 335                         {
 336                                 struct sockaddr_atmsvc addr;
 337
 338                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
 339                                         error = -EFAULT;
 340                                         goto done;
 341                                 }
 342                                 if (cmd == ATM_ADDADDR)
 343                                         error = atm_add_addr(dev, &addr);
 344                                 else
 345                                         error = atm_del_addr(dev, &addr);
 346                                 goto done;
 347                         }
 348                 case ATM_GETADDR:
 349                         error = atm_get_addr(dev, buf, len);
 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->length)
 356                                 ? -EFAULT : 0;
 357                         goto done;
 358                 case ATM_SETLOOP:
 359                         if (__ATM_LM_XTRMT((int) (long) buf) &&
 360                             __ATM_LM_XTLOC((int) (long) buf) >
 361                             __ATM_LM_XTRMT((int) (long) buf)) {
 362                                 error = -EINVAL;
 363                                 goto done;
 364                         }
 365                         /* fall through */
 366                 case ATM_SETCIRANGE:
 367                 case SONET_GETSTATZ:
 368                 case SONET_SETDIAG:
 369                 case SONET_CLRDIAG:
 370                 case SONET_SETFRAMING:
 371                         if (!capable(CAP_NET_ADMIN)) {
 372                                 error = -EPERM;
 373                                 goto done;
 374                         }
 375                         /* fall through */
 376                 default:
 377                         if (!dev->ops->ioctl) {
 378                                 error = -EINVAL;
 379                                 goto done;
 380                         }
 381                         size = dev->ops->ioctl(dev, cmd, buf);
 382                         if (size < 0) {
 383                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
 384                                 goto done;
 385                         }
 386         }
 387
 388         if (size)
 389                 error = put_user(size, &sioc->length)
 390                         ? -EFAULT : 0;
 391         else
 392                 error = 0;
 393 done:
 394         atm_dev_put(dev);
 395         return error;
 396 }
 397
 398 static __inline__ void *dev_get_idx(loff_t left)
 399 {
 400         struct list_head *p;
 401
 402         list_for_each(p, &atm_devs) {
 403                 if (!--left)
 404                         break;
 405         }
 406         return (p != &atm_devs) ? p : NULL;
 407 }
 408
 409 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
 410 {
 411         spin_lock(&atm_dev_lock);
 412         return *pos ? dev_get_idx(*pos) : (void *) 1;
 413 }
 414
 415 void atm_dev_seq_stop(struct seq_file *seq, void *v)
 416 {
 417         spin_unlock(&atm_dev_lock);
 418 }
 419
 420 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 421 {
 422         ++*pos;
 423         v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
 424         return (v == &atm_devs) ? NULL : v;
 425 }
 426
 427
 428 EXPORT_SYMBOL(atm_dev_register);
 429 EXPORT_SYMBOL(atm_dev_deregister);
 430 EXPORT_SYMBOL(atm_dev_lookup);
 431 EXPORT_SYMBOL(shutdown_atm_dev);