net/atm/resources.c

   1 /* net/atm/resources.c - Staticly allocated resources */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5
   6 #include <linux/config.h>
   7 #include <linux/ctype.h>
   8 #include <linux/string.h>
   9 #include <linux/atmdev.h>
  10 #include <linux/sonet.h>
  11 #include <linux/kernel.h> /* for barrier */
  12 #include <linux/module.h>
  13 #include <linux/bitops.h>
  14 #include <net/sock.h>    /* for struct sock */
  15 #include <asm/segment.h> /* for get_fs_long and put_fs_long */
  16
  17 #include "common.h"
  18 #include "resources.h"
  19 #include "addr.h"
  20
  21
  22 LIST_HEAD(atm_devs);
  23 spinlock_t atm_dev_lock = SPIN_LOCK_UNLOCKED;
  24
  25
  26 static struct atm_dev *__alloc_atm_dev(const char *type)
  27 {
  28         struct atm_dev *dev;
  29
  30         dev = kmalloc(sizeof(*dev), GFP_ATOMIC);
  31         if (!dev)
  32                 return NULL;
  33         memset(dev, 0, sizeof(*dev));
  34         dev->type = type;
  35         dev->signal = ATM_PHY_SIG_UNKNOWN;
  36         dev->link_rate = ATM_OC3_PCR;
  37         spin_lock_init(&dev->lock);
  38
  39         return dev;
  40 }
  41
  42
  43 static void __free_atm_dev(struct atm_dev *dev)
  44 {
  45         kfree(dev);
  46 }
  47
  48 static struct atm_dev *__atm_dev_lookup(int number)
  49 {
  50         struct atm_dev *dev;
  51         struct list_head *p;
  52
  53         list_for_each(p, &atm_devs) {
  54                 dev = list_entry(p, struct atm_dev, dev_list);
  55                 if ((dev->ops) && (dev->number == number)) {
  56                         atm_dev_hold(dev);
  57                         return dev;
  58                 }
  59         }
  60         return NULL;
  61 }
  62
  63 struct atm_dev *atm_dev_lookup(int number)
  64 {
  65         struct atm_dev *dev;
  66
  67         spin_lock(&atm_dev_lock);
  68         dev = __atm_dev_lookup(number);
  69         spin_unlock(&atm_dev_lock);
  70         return dev;
  71 }
  72
  73 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
  74                                  int number, atm_dev_flags_t *flags)
  75 {
  76         struct atm_dev *dev, *inuse;
  77
  78
  79         dev = __alloc_atm_dev(type);
  80         if (!dev) {
  81                 printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
  82                     type);
  83                 return NULL;
  84         }
  85         spin_lock(&atm_dev_lock);
  86         if (number != -1) {
  87                 if ((inuse = __atm_dev_lookup(number))) {
  88                         atm_dev_put(inuse);
  89                         spin_unlock(&atm_dev_lock);
  90                         __free_atm_dev(dev);
  91                         return NULL;
  92                 }
  93                 dev->number = number;
  94         } else {
  95                 dev->number = 0;
  96                 while ((inuse = __atm_dev_lookup(dev->number))) {
  97                         atm_dev_put(inuse);
  98                         dev->number++;
  99                 }
 100         }
 101
 102         dev->ops = ops;
 103         if (flags)
 104                 dev->flags = *flags;
 105         else
 106                 memset(&dev->flags, 0, sizeof(dev->flags));
 107         memset(&dev->stats, 0, sizeof(dev->stats));
 108         atomic_set(&dev->refcnt, 1);
 109         list_add_tail(&dev->dev_list, &atm_devs);
 110         spin_unlock(&atm_dev_lock);
 111
 112 #ifdef CONFIG_PROC_FS
 113         if (ops->proc_read) {
 114                 if (atm_proc_dev_register(dev) < 0) {
 115                         printk(KERN_ERR "atm_dev_register: "
 116                                "atm_proc_dev_register failed for dev %s\n",
 117                                type);
 118                         spin_lock(&atm_dev_lock);
 119                         list_del(&dev->dev_list);
 120                         spin_unlock(&atm_dev_lock);
 121                         __free_atm_dev(dev);
 122                         return NULL;
 123                 }
 124         }
 125 #endif
 126
 127         return dev;
 128 }
 129
 130
 131 void atm_dev_deregister(struct atm_dev *dev)
 132 {
 133         unsigned long warning_time;
 134
 135 #ifdef CONFIG_PROC_FS
 136         if (dev->ops->proc_read)
 137                 atm_proc_dev_deregister(dev);
 138 #endif
 139         spin_lock(&atm_dev_lock);
 140         list_del(&dev->dev_list);
 141         spin_unlock(&atm_dev_lock);
 142
 143         warning_time = jiffies;
 144         while (atomic_read(&dev->refcnt) != 1) {
 145                 current->state = TASK_INTERRUPTIBLE;
 146                 schedule_timeout(HZ / 4);
 147                 current->state = TASK_RUNNING;
 148                 if ((jiffies - warning_time) > 10 * HZ) {
 149                         printk(KERN_EMERG "atm_dev_deregister: waiting for "
 150                                "dev %d to become free. Usage count = %d\n",
 151                                dev->number, atomic_read(&dev->refcnt));
 152                         warning_time = jiffies;
 153                 }
 154         }
 155
 156         __free_atm_dev(dev);
 157 }
 158
 159 void shutdown_atm_dev(struct atm_dev *dev)
 160 {
 161         if (atomic_read(&dev->refcnt) > 1) {
 162                 set_bit(ATM_DF_CLOSE, &dev->flags);
 163                 return;
 164         }
 165         if (dev->ops->dev_close)
 166                 dev->ops->dev_close(dev);
 167         atm_dev_deregister(dev);
 168 }
 169
 170
 171 static void copy_aal_stats(struct k_atm_aal_stats *from,
 172     struct atm_aal_stats *to)
 173 {
 174 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
 175         __AAL_STAT_ITEMS
 176 #undef __HANDLE_ITEM
 177 }
 178
 179
 180 static void subtract_aal_stats(struct k_atm_aal_stats *from,
 181     struct atm_aal_stats *to)
 182 {
 183 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
 184         __AAL_STAT_ITEMS
 185 #undef __HANDLE_ITEM
 186 }
 187
 188
 189 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats *arg, int zero)
 190 {
 191         struct atm_dev_stats tmp;
 192         int error = 0;
 193
 194         copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
 195         copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
 196         copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
 197         if (arg)
 198                 error = copy_to_user(arg, &tmp, sizeof(tmp));
 199         if (zero && !error) {
 200                 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
 201                 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
 202                 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
 203         }
 204         return error ? -EFAULT : 0;
 205 }
 206
 207
 208 int atm_dev_ioctl(unsigned int cmd, unsigned long arg)
 209 {
 210         void *buf;
 211         int error = 0, len, number, size = 0;
 212         struct atm_dev *dev;
 213
 214         if (cmd == ATM_GETNAMES) {
 215                 int *tmp_buf, *tmp_bufp;
 216                 struct list_head *p;
 217                 /*
 218                  * ATM_GETNAMES is a special case: it doesn't require a
 219                  * device number argument
 220                  */
 221                 if (get_user(buf, &((struct atm_iobuf *) arg)->buffer))
 222                         return -EFAULT;
 223                 if (get_user(len, &((struct atm_iobuf *) arg)->length))
 224                         return -EFAULT;
 225                 spin_lock(&atm_dev_lock);
 226                 list_for_each(p, &atm_devs)
 227                         size += sizeof(int);
 228                 if (size > len) {
 229                         spin_unlock(&atm_dev_lock);
 230                         return -E2BIG;
 231                 }
 232                 tmp_buf = tmp_bufp = kmalloc(size, GFP_ATOMIC);
 233                 if (!tmp_buf) {
 234                         spin_unlock(&atm_dev_lock);
 235                         return -ENOMEM;
 236                 }
 237                 list_for_each(p, &atm_devs) {
 238                         dev = list_entry(p, struct atm_dev, dev_list);
 239                         *tmp_bufp++ = dev->number;
 240                 }
 241                 spin_unlock(&atm_dev_lock);
 242                 error = (copy_to_user(buf, tmp_buf, size) ||
 243                                 put_user(size, &((struct atm_iobuf *) arg)->length))
 244                                         ? -EFAULT : 0;
 245                 kfree(tmp_buf);
 246                 return error;
 247         }
 248
 249         if (get_user(buf, &((struct atmif_sioc *) arg)->arg))
 250                 return -EFAULT;
 251         if (get_user(len, &((struct atmif_sioc *) arg)->length))
 252                 return -EFAULT;
 253         if (get_user(number, &((struct atmif_sioc *) arg)->number))
 254                 return -EFAULT;
 255
 256         if (!(dev = atm_dev_lookup(number)))
 257                 return -ENODEV;
 258
 259         switch (cmd) {
 260                 case ATM_GETTYPE:
 261                         size = strlen(dev->type) + 1;
 262                         if (copy_to_user(buf, dev->type, size)) {
 263                                 error = -EFAULT;
 264                                 goto done;
 265                         }
 266                         break;
 267                 case ATM_GETESI:
 268                         size = ESI_LEN;
 269                         if (copy_to_user(buf, dev->esi, size)) {
 270                                 error = -EFAULT;
 271                                 goto done;
 272                         }
 273                         break;
 274                 case ATM_SETESI:
 275                         {
 276                                 int i;
 277
 278                                 for (i = 0; i < ESI_LEN; i++)
 279                                         if (dev->esi[i]) {
 280                                                 error = -EEXIST;
 281                                                 goto done;
 282                                         }
 283                         }
 284                         /* fall through */
 285                 case ATM_SETESIF:
 286                         {
 287                                 unsigned char esi[ESI_LEN];
 288
 289                                 if (!capable(CAP_NET_ADMIN)) {
 290                                         error = -EPERM;
 291                                         goto done;
 292                                 }
 293                                 if (copy_from_user(esi, buf, ESI_LEN)) {
 294                                         error = -EFAULT;
 295                                         goto done;
 296                                 }
 297                                 memcpy(dev->esi, esi, ESI_LEN);
 298                                 error =  ESI_LEN;
 299                                 goto done;
 300                         }
 301                 case ATM_GETSTATZ:
 302                         if (!capable(CAP_NET_ADMIN)) {
 303                                 error = -EPERM;
 304                                 goto done;
 305                         }
 306                         /* fall through */
 307                 case ATM_GETSTAT:
 308                         size = sizeof(struct atm_dev_stats);
 309                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 310                         if (error)
 311                                 goto done;
 312                         break;
 313                 case ATM_GETCIRANGE:
 314                         size = sizeof(struct atm_cirange);
 315                         if (copy_to_user(buf, &dev->ci_range, size)) {
 316                                 error = -EFAULT;
 317                                 goto done;
 318                         }
 319                         break;
 320                 case ATM_GETLINKRATE:
 321                         size = sizeof(int);
 322                         if (copy_to_user(buf, &dev->link_rate, size)) {
 323                                 error = -EFAULT;
 324                                 goto done;
 325                         }
 326                         break;
 327                 case ATM_RSTADDR:
 328                         if (!capable(CAP_NET_ADMIN)) {
 329                                 error = -EPERM;
 330                                 goto done;
 331                         }
 332                         atm_reset_addr(dev);
 333                         break;
 334                 case ATM_ADDADDR:
 335                 case ATM_DELADDR:
 336                         if (!capable(CAP_NET_ADMIN)) {
 337                                 error = -EPERM;
 338                                 goto done;
 339                         }
 340                         {
 341                                 struct sockaddr_atmsvc addr;
 342
 343                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
 344                                         error = -EFAULT;
 345                                         goto done;
 346                                 }
 347                                 if (cmd == ATM_ADDADDR)
 348                                         error = atm_add_addr(dev, &addr);
 349                                 else
 350                                         error = atm_del_addr(dev, &addr);
 351                                 goto done;
 352                         }
 353                 case ATM_GETADDR:
 354                         error = atm_get_addr(dev, buf, len);
 355                         if (error < 0)
 356                                 goto done;
 357                         size = error;
 358                         /* write back size even if it's zero */
 359                         goto write_size;
 360                 case ATM_SETLOOP:
 361                         if (__ATM_LM_XTRMT((int) (long) buf) &&
 362                             __ATM_LM_XTLOC((int) (long) buf) >
 363                             __ATM_LM_XTRMT((int) (long) buf)) {
 364                                 error = -EINVAL;
 365                                 goto done;
 366                         }
 367                         /* fall through */
 368                 case ATM_SETCIRANGE:
 369                 case SONET_GETSTATZ:
 370                 case SONET_SETDIAG:
 371                 case SONET_CLRDIAG:
 372                 case SONET_SETFRAMING:
 373                         if (!capable(CAP_NET_ADMIN)) {
 374                                 error = -EPERM;
 375                                 goto done;
 376                         }
 377                         /* fall through */
 378                 default:
 379                         if (!dev->ops->ioctl) {
 380                                 error = -EINVAL;
 381                                 goto done;
 382                         }
 383                         size = dev->ops->ioctl(dev, cmd, buf);
 384                         if (size < 0) {
 385                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
 386                                 goto done;
 387                         }
 388         }
 389
 390         if (size) {
 391 write_size:
 392                 error = put_user(size,
 393                           &((struct atmif_sioc *) arg)->length)
 394                           ? -EFAULT : 0;
 395         }
 396 done:
 397         atm_dev_put(dev);
 398         return error;
 399 }
 400
 401
 402 EXPORT_SYMBOL(atm_dev_register);
 403 EXPORT_SYMBOL(atm_dev_deregister);
 404 EXPORT_SYMBOL(atm_dev_lookup);
 405 EXPORT_SYMBOL(shutdown_atm_dev);