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 <linux/delay.h>
  20 #include <net/sock.h>    /* for struct sock */
  21
  22 #include "common.h"
  23 #include "resources.h"
  24 #include "addr.h"
  25
  26
  27 LIST_HEAD(atm_devs);
  28 DEFINE_SPINLOCK(atm_dev_lock);
  29
  30 static struct atm_dev *__alloc_atm_dev(const char *type)
  31 {
  32         struct atm_dev *dev;
  33
  34         dev = kmalloc(sizeof(*dev), GFP_KERNEL);
  35         if (!dev)
  36                 return NULL;
  37         memset(dev, 0, sizeof(*dev));
  38         dev->type = type;
  39         dev->signal = ATM_PHY_SIG_UNKNOWN;
  40         dev->link_rate = ATM_OC3_PCR;
  41         spin_lock_init(&dev->lock);
  42         INIT_LIST_HEAD(&dev->local);
  43
  44         return dev;
  45 }
  46
  47 static void __free_atm_dev(struct atm_dev *dev)
  48 {
  49         kfree(dev);
  50 }
  51
  52 static 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->ops) && (dev->number == number)) {
  60                         atm_dev_hold(dev);
  61                         return dev;
  62                 }
  63         }
  64         return NULL;
  65 }
  66
  67 struct atm_dev *atm_dev_lookup(int number)
  68 {
  69         struct atm_dev *dev;
  70
  71         spin_lock(&atm_dev_lock);
  72         dev = __atm_dev_lookup(number);
  73         spin_unlock(&atm_dev_lock);
  74         return dev;
  75 }
  76
  77 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
  78                                  int number, unsigned long *flags)
  79 {
  80         struct atm_dev *dev, *inuse;
  81
  82         dev = __alloc_atm_dev(type);
  83         if (!dev) {
  84                 printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
  85                     type);
  86                 return NULL;
  87         }
  88         spin_lock(&atm_dev_lock);
  89         if (number != -1) {
  90                 if ((inuse = __atm_dev_lookup(number))) {
  91                         atm_dev_put(inuse);
  92                         spin_unlock(&atm_dev_lock);
  93                         __free_atm_dev(dev);
  94                         return NULL;
  95                 }
  96                 dev->number = number;
  97         } else {
  98                 dev->number = 0;
  99                 while ((inuse = __atm_dev_lookup(dev->number))) {
 100                         atm_dev_put(inuse);
 101                         dev->number++;
 102                 }
 103         }
 104
 105         dev->ops = ops;
 106         if (flags)
 107                 dev->flags = *flags;
 108         else
 109                 memset(&dev->flags, 0, sizeof(dev->flags));
 110         memset(&dev->stats, 0, sizeof(dev->stats));
 111         atomic_set(&dev->refcnt, 1);
 112         list_add_tail(&dev->dev_list, &atm_devs);
 113         spin_unlock(&atm_dev_lock);
 114
 115         if (atm_proc_dev_register(dev) < 0) {
 116                 printk(KERN_ERR "atm_dev_register: "
 117                        "atm_proc_dev_register failed for dev %s\n",
 118                        type);
 119                 spin_lock(&atm_dev_lock);
 120                 list_del(&dev->dev_list);
 121                 spin_unlock(&atm_dev_lock);
 122                 __free_atm_dev(dev);
 123                 return NULL;
 124         }
 125
 126         return dev;
 127 }
 128
 129
 130 void atm_dev_deregister(struct atm_dev *dev)
 131 {
 132         unsigned long warning_time;
 133
 134         atm_proc_dev_deregister(dev);
 135
 136         spin_lock(&atm_dev_lock);
 137         list_del(&dev->dev_list);
 138         spin_unlock(&atm_dev_lock);
 139
 140         warning_time = jiffies;
 141         while (atomic_read(&dev->refcnt) != 1) {
 142                 msleep(250);
 143                 if ((jiffies - warning_time) > 10 * HZ) {
 144                         printk(KERN_EMERG "atm_dev_deregister: waiting for "
 145                                "dev %d to become free. Usage count = %d\n",
 146                                dev->number, atomic_read(&dev->refcnt));
 147                         warning_time = jiffies;
 148                 }
 149         }
 150
 151         __free_atm_dev(dev);
 152 }
 153
 154 void shutdown_atm_dev(struct atm_dev *dev)
 155 {
 156         if (atomic_read(&dev->refcnt) > 1) {
 157                 set_bit(ATM_DF_CLOSE, &dev->flags);
 158                 return;
 159         }
 160         if (dev->ops->dev_close)
 161                 dev->ops->dev_close(dev);
 162         atm_dev_deregister(dev);
 163 }
 164
 165
 166 static void copy_aal_stats(struct k_atm_aal_stats *from,
 167     struct atm_aal_stats *to)
 168 {
 169 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
 170         __AAL_STAT_ITEMS
 171 #undef __HANDLE_ITEM
 172 }
 173
 174
 175 static void subtract_aal_stats(struct k_atm_aal_stats *from,
 176     struct atm_aal_stats *to)
 177 {
 178 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
 179         __AAL_STAT_ITEMS
 180 #undef __HANDLE_ITEM
 181 }
 182
 183
 184 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
 185 {
 186         struct atm_dev_stats tmp;
 187         int error = 0;
 188
 189         copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
 190         copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
 191         copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
 192         if (arg)
 193                 error = copy_to_user(arg, &tmp, sizeof(tmp));
 194         if (zero && !error) {
 195                 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
 196                 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
 197                 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
 198         }
 199         return error ? -EFAULT : 0;
 200 }
 201
 202
 203 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
 204 {
 205         void __user *buf;
 206         int error, len, number, size = 0;
 207         struct atm_dev *dev;
 208         struct list_head *p;
 209         int *tmp_buf, *tmp_p;
 210         struct atm_iobuf __user *iobuf = arg;
 211         struct atmif_sioc __user *sioc = arg;
 212         switch (cmd) {
 213                 case ATM_GETNAMES:
 214                         if (get_user(buf, &iobuf->buffer))
 215                                 return -EFAULT;
 216                         if (get_user(len, &iobuf->length))
 217                                 return -EFAULT;
 218                         spin_lock(&atm_dev_lock);
 219                         list_for_each(p, &atm_devs)
 220                                 size += sizeof(int);
 221                         if (size > len) {
 222                                 spin_unlock(&atm_dev_lock);
 223                                 return -E2BIG;
 224                         }
 225                         tmp_buf = kmalloc(size, GFP_ATOMIC);
 226                         if (!tmp_buf) {
 227                                 spin_unlock(&atm_dev_lock);
 228                                 return -ENOMEM;
 229                         }
 230                         tmp_p = tmp_buf;
 231                         list_for_each(p, &atm_devs) {
 232                                 dev = list_entry(p, struct atm_dev, dev_list);
 233                                 *tmp_p++ = dev->number;
 234                         }
 235                         spin_unlock(&atm_dev_lock);
 236                         error = ((copy_to_user(buf, tmp_buf, size)) ||
 237                                         put_user(size, &iobuf->length))
 238                                                 ? -EFAULT : 0;
 239                         kfree(tmp_buf);
 240                         return error;
 241                 default:
 242                         break;
 243         }
 244
 245         if (get_user(buf, &sioc->arg))
 246                 return -EFAULT;
 247         if (get_user(len, &sioc->length))
 248                 return -EFAULT;
 249         if (get_user(number, &sioc->number))
 250                 return -EFAULT;
 251
 252         if (!(dev = atm_dev_lookup(number)))
 253                 return -ENODEV;
 254
 255         switch (cmd) {
 256                 case ATM_GETTYPE:
 257                         size = strlen(dev->type) + 1;
 258                         if (copy_to_user(buf, dev->type, size)) {
 259                                 error = -EFAULT;
 260                                 goto done;
 261                         }
 262                         break;
 263                 case ATM_GETESI:
 264                         size = ESI_LEN;
 265                         if (copy_to_user(buf, dev->esi, size)) {
 266                                 error = -EFAULT;
 267                                 goto done;
 268                         }
 269                         break;
 270                 case ATM_SETESI:
 271                         {
 272                                 int i;
 273
 274                                 for (i = 0; i < ESI_LEN; i++)
 275                                         if (dev->esi[i]) {
 276                                                 error = -EEXIST;
 277                                                 goto done;
 278                                         }
 279                         }
 280                         /* fall through */
 281                 case ATM_SETESIF:
 282                         {
 283                                 unsigned char esi[ESI_LEN];
 284
 285                                 if (!capable(CAP_NET_ADMIN)) {
 286                                         error = -EPERM;
 287                                         goto done;
 288                                 }
 289                                 if (copy_from_user(esi, buf, ESI_LEN)) {
 290                                         error = -EFAULT;
 291                                         goto done;
 292                                 }
 293                                 memcpy(dev->esi, esi, ESI_LEN);
 294                                 error =  ESI_LEN;
 295                                 goto done;
 296                         }
 297                 case ATM_GETSTATZ:
 298                         if (!capable(CAP_NET_ADMIN)) {
 299                                 error = -EPERM;
 300                                 goto done;
 301                         }
 302                         /* fall through */
 303                 case ATM_GETSTAT:
 304                         size = sizeof(struct atm_dev_stats);
 305                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 306                         if (error)
 307                                 goto done;
 308                         break;
 309                 case ATM_GETCIRANGE:
 310                         size = sizeof(struct atm_cirange);
 311                         if (copy_to_user(buf, &dev->ci_range, size)) {
 312                                 error = -EFAULT;
 313                                 goto done;
 314                         }
 315                         break;
 316                 case ATM_GETLINKRATE:
 317                         size = sizeof(int);
 318                         if (copy_to_user(buf, &dev->link_rate, size)) {
 319                                 error = -EFAULT;
 320                                 goto done;
 321                         }
 322                         break;
 323                 case ATM_RSTADDR:
 324                         if (!capable(CAP_NET_ADMIN)) {
 325                                 error = -EPERM;
 326                                 goto done;
 327                         }
 328                         atm_reset_addr(dev);
 329                         break;
 330                 case ATM_ADDADDR:
 331                 case ATM_DELADDR:
 332                         if (!capable(CAP_NET_ADMIN)) {
 333                                 error = -EPERM;
 334                                 goto done;
 335                         }
 336                         {
 337                                 struct sockaddr_atmsvc addr;
 338
 339                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
 340                                         error = -EFAULT;
 341                                         goto done;
 342                                 }
 343                                 if (cmd == ATM_ADDADDR)
 344                                         error = atm_add_addr(dev, &addr);
 345                                 else
 346                                         error = atm_del_addr(dev, &addr);
 347                                 goto done;
 348                         }
 349                 case ATM_GETADDR:
 350                         error = atm_get_addr(dev, buf, len);
 351                         if (error < 0)
 352                                 goto done;
 353                         size = error;
 354                         /* may return 0, but later on size == 0 means "don't
 355                            write the length" */
 356                         error = put_user(size, &sioc->length)
 357                                 ? -EFAULT : 0;
 358                         goto done;
 359                 case ATM_SETLOOP:
 360                         if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
 361                             __ATM_LM_XTLOC((int) (unsigned long) buf) >
 362                             __ATM_LM_XTRMT((int) (unsigned long) buf)) {
 363                                 error = -EINVAL;
 364                                 goto done;
 365                         }
 366                         /* fall through */
 367                 case ATM_SETCIRANGE:
 368                 case SONET_GETSTATZ:
 369                 case SONET_SETDIAG:
 370                 case SONET_CLRDIAG:
 371                 case SONET_SETFRAMING:
 372                         if (!capable(CAP_NET_ADMIN)) {
 373                                 error = -EPERM;
 374                                 goto done;
 375                         }
 376                         /* fall through */
 377                 default:
 378                         if (!dev->ops->ioctl) {
 379                                 error = -EINVAL;
 380                                 goto done;
 381                         }
 382                         size = dev->ops->ioctl(dev, cmd, buf);
 383                         if (size < 0) {
 384                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
 385                                 goto done;
 386                         }
 387         }
 388
 389         if (size)
 390                 error = put_user(size, &sioc->length)
 391                         ? -EFAULT : 0;
 392         else
 393                 error = 0;
 394 done:
 395         atm_dev_put(dev);
 396         return error;
 397 }
 398
 399 static __inline__ void *dev_get_idx(loff_t left)
 400 {
 401         struct list_head *p;
 402
 403         list_for_each(p, &atm_devs) {
 404                 if (!--left)
 405                         break;
 406         }
 407         return (p != &atm_devs) ? p : NULL;
 408 }
 409
 410 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
 411 {
 412         spin_lock(&atm_dev_lock);
 413         return *pos ? dev_get_idx(*pos) : (void *) 1;
 414 }
 415
 416 void atm_dev_seq_stop(struct seq_file *seq, void *v)
 417 {
 418         spin_unlock(&atm_dev_lock);
 419 }
 420
 421 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 422 {
 423         ++*pos;
 424         v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
 425         return (v == &atm_devs) ? NULL : v;
 426 }
 427
 428
 429 EXPORT_SYMBOL(atm_dev_register);
 430 EXPORT_SYMBOL(atm_dev_deregister);
 431 EXPORT_SYMBOL(atm_dev_lookup);
 432 EXPORT_SYMBOL(shutdown_atm_dev);