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 struct atm_dev *__atm_dev_lookup(int number)
  48 {
  49         struct atm_dev *dev;
  50         struct list_head *p;
  51
  52         list_for_each(p, &atm_devs) {
  53                 dev = list_entry(p, struct atm_dev, dev_list);
  54                 if ((dev->ops) && (dev->number == number)) {
  55                         atm_dev_hold(dev);
  56                         return dev;
  57                 }
  58         }
  59         return NULL;
  60 }
  61
  62 struct atm_dev *atm_dev_lookup(int number)
  63 {
  64         struct atm_dev *dev;
  65
  66         spin_lock(&atm_dev_lock);
  67         dev = __atm_dev_lookup(number);
  68         spin_unlock(&atm_dev_lock);
  69         return dev;
  70 }
  71
  72 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
  73                                  int number, unsigned long *flags)
  74 {
  75         struct atm_dev *dev, *inuse;
  76
  77         dev = __alloc_atm_dev(type);
  78         if (!dev) {
  79                 printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
  80                     type);
  81                 return NULL;
  82         }
  83         spin_lock(&atm_dev_lock);
  84         if (number != -1) {
  85                 if ((inuse = __atm_dev_lookup(number))) {
  86                         atm_dev_put(inuse);
  87                         spin_unlock(&atm_dev_lock);
  88                         kfree(dev);
  89                         return NULL;
  90                 }
  91                 dev->number = number;
  92         } else {
  93                 dev->number = 0;
  94                 while ((inuse = __atm_dev_lookup(dev->number))) {
  95                         atm_dev_put(inuse);
  96                         dev->number++;
  97                 }
  98         }
  99
 100         dev->ops = ops;
 101         if (flags)
 102                 dev->flags = *flags;
 103         else
 104                 memset(&dev->flags, 0, sizeof(dev->flags));
 105         memset(&dev->stats, 0, sizeof(dev->stats));
 106         atomic_set(&dev->refcnt, 1);
 107         list_add_tail(&dev->dev_list, &atm_devs);
 108         spin_unlock(&atm_dev_lock);
 109
 110         if (atm_proc_dev_register(dev) < 0) {
 111                 printk(KERN_ERR "atm_dev_register: "
 112                        "atm_proc_dev_register failed for dev %s\n",
 113                        type);
 114                 spin_lock(&atm_dev_lock);
 115                 list_del(&dev->dev_list);
 116                 spin_unlock(&atm_dev_lock);
 117                 kfree(dev);
 118                 return NULL;
 119         }
 120
 121         return dev;
 122 }
 123
 124
 125 void atm_dev_deregister(struct atm_dev *dev)
 126 {
 127         unsigned long warning_time;
 128
 129         atm_proc_dev_deregister(dev);
 130
 131         spin_lock(&atm_dev_lock);
 132         list_del(&dev->dev_list);
 133         spin_unlock(&atm_dev_lock);
 134
 135         warning_time = jiffies;
 136         while (atomic_read(&dev->refcnt) != 1) {
 137                 msleep(250);
 138                 if ((jiffies - warning_time) > 10 * HZ) {
 139                         printk(KERN_EMERG "atm_dev_deregister: waiting for "
 140                                "dev %d to become free. Usage count = %d\n",
 141                                dev->number, atomic_read(&dev->refcnt));
 142                         warning_time = jiffies;
 143                 }
 144         }
 145
 146         kfree(dev);
 147 }
 148
 149 void shutdown_atm_dev(struct atm_dev *dev)
 150 {
 151         if (atomic_read(&dev->refcnt) > 1) {
 152                 set_bit(ATM_DF_CLOSE, &dev->flags);
 153                 return;
 154         }
 155         if (dev->ops->dev_close)
 156                 dev->ops->dev_close(dev);
 157         atm_dev_deregister(dev);
 158 }
 159
 160
 161 static 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
 169
 170 static void subtract_aal_stats(struct k_atm_aal_stats *from,
 171     struct atm_aal_stats *to)
 172 {
 173 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
 174         __AAL_STAT_ITEMS
 175 #undef __HANDLE_ITEM
 176 }
 177
 178
 179 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
 180 {
 181         struct atm_dev_stats tmp;
 182         int error = 0;
 183
 184         copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
 185         copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
 186         copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
 187         if (arg)
 188                 error = copy_to_user(arg, &tmp, sizeof(tmp));
 189         if (zero && !error) {
 190                 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
 191                 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
 192                 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
 193         }
 194         return error ? -EFAULT : 0;
 195 }
 196
 197
 198 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
 199 {
 200         void __user *buf;
 201         int error, len, number, size = 0;
 202         struct atm_dev *dev;
 203         struct list_head *p;
 204         int *tmp_buf, *tmp_p;
 205         struct atm_iobuf __user *iobuf = arg;
 206         struct atmif_sioc __user *sioc = arg;
 207         switch (cmd) {
 208                 case ATM_GETNAMES:
 209                         if (get_user(buf, &iobuf->buffer))
 210                                 return -EFAULT;
 211                         if (get_user(len, &iobuf->length))
 212                                 return -EFAULT;
 213                         spin_lock(&atm_dev_lock);
 214                         list_for_each(p, &atm_devs)
 215                                 size += sizeof(int);
 216                         if (size > len) {
 217                                 spin_unlock(&atm_dev_lock);
 218                                 return -E2BIG;
 219                         }
 220                         tmp_buf = kmalloc(size, GFP_ATOMIC);
 221                         if (!tmp_buf) {
 222                                 spin_unlock(&atm_dev_lock);
 223                                 return -ENOMEM;
 224                         }
 225                         tmp_p = tmp_buf;
 226                         list_for_each(p, &atm_devs) {
 227                                 dev = list_entry(p, struct atm_dev, dev_list);
 228                                 *tmp_p++ = dev->number;
 229                         }
 230                         spin_unlock(&atm_dev_lock);
 231                         error = ((copy_to_user(buf, tmp_buf, size)) ||
 232                                         put_user(size, &iobuf->length))
 233                                                 ? -EFAULT : 0;
 234                         kfree(tmp_buf);
 235                         return error;
 236                 default:
 237                         break;
 238         }
 239
 240         if (get_user(buf, &sioc->arg))
 241                 return -EFAULT;
 242         if (get_user(len, &sioc->length))
 243                 return -EFAULT;
 244         if (get_user(number, &sioc->number))
 245                 return -EFAULT;
 246
 247         if (!(dev = atm_dev_lookup(number)))
 248                 return -ENODEV;
 249
 250         switch (cmd) {
 251                 case ATM_GETTYPE:
 252                         size = strlen(dev->type) + 1;
 253                         if (copy_to_user(buf, dev->type, size)) {
 254                                 error = -EFAULT;
 255                                 goto done;
 256                         }
 257                         break;
 258                 case ATM_GETESI:
 259                         size = ESI_LEN;
 260                         if (copy_to_user(buf, dev->esi, size)) {
 261                                 error = -EFAULT;
 262                                 goto done;
 263                         }
 264                         break;
 265                 case ATM_SETESI:
 266                         {
 267                                 int i;
 268
 269                                 for (i = 0; i < ESI_LEN; i++)
 270                                         if (dev->esi[i]) {
 271                                                 error = -EEXIST;
 272                                                 goto done;
 273                                         }
 274                         }
 275                         /* fall through */
 276                 case ATM_SETESIF:
 277                         {
 278                                 unsigned char esi[ESI_LEN];
 279
 280                                 if (!capable(CAP_NET_ADMIN)) {
 281                                         error = -EPERM;
 282                                         goto done;
 283                                 }
 284                                 if (copy_from_user(esi, buf, ESI_LEN)) {
 285                                         error = -EFAULT;
 286                                         goto done;
 287                                 }
 288                                 memcpy(dev->esi, esi, ESI_LEN);
 289                                 error =  ESI_LEN;
 290                                 goto done;
 291                         }
 292                 case ATM_GETSTATZ:
 293                         if (!capable(CAP_NET_ADMIN)) {
 294                                 error = -EPERM;
 295                                 goto done;
 296                         }
 297                         /* fall through */
 298                 case ATM_GETSTAT:
 299                         size = sizeof(struct atm_dev_stats);
 300                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
 301                         if (error)
 302                                 goto done;
 303                         break;
 304                 case ATM_GETCIRANGE:
 305                         size = sizeof(struct atm_cirange);
 306                         if (copy_to_user(buf, &dev->ci_range, size)) {
 307                                 error = -EFAULT;
 308                                 goto done;
 309                         }
 310                         break;
 311                 case ATM_GETLINKRATE:
 312                         size = sizeof(int);
 313                         if (copy_to_user(buf, &dev->link_rate, size)) {
 314                                 error = -EFAULT;
 315                                 goto done;
 316                         }
 317                         break;
 318                 case ATM_RSTADDR:
 319                         if (!capable(CAP_NET_ADMIN)) {
 320                                 error = -EPERM;
 321                                 goto done;
 322                         }
 323                         atm_reset_addr(dev);
 324                         break;
 325                 case ATM_ADDADDR:
 326                 case ATM_DELADDR:
 327                         if (!capable(CAP_NET_ADMIN)) {
 328                                 error = -EPERM;
 329                                 goto done;
 330                         }
 331                         {
 332                                 struct sockaddr_atmsvc addr;
 333
 334                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
 335                                         error = -EFAULT;
 336                                         goto done;
 337                                 }
 338                                 if (cmd == ATM_ADDADDR)
 339                                         error = atm_add_addr(dev, &addr);
 340                                 else
 341                                         error = atm_del_addr(dev, &addr);
 342                                 goto done;
 343                         }
 344                 case ATM_GETADDR:
 345                         error = atm_get_addr(dev, buf, len);
 346                         if (error < 0)
 347                                 goto done;
 348                         size = error;
 349                         /* may return 0, but later on size == 0 means "don't
 350                            write the length" */
 351                         error = put_user(size, &sioc->length)
 352                                 ? -EFAULT : 0;
 353                         goto done;
 354                 case ATM_SETLOOP:
 355                         if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
 356                             __ATM_LM_XTLOC((int) (unsigned long) buf) >
 357                             __ATM_LM_XTRMT((int) (unsigned long) buf)) {
 358                                 error = -EINVAL;
 359                                 goto done;
 360                         }
 361                         /* fall through */
 362                 case ATM_SETCIRANGE:
 363                 case SONET_GETSTATZ:
 364                 case SONET_SETDIAG:
 365                 case SONET_CLRDIAG:
 366                 case SONET_SETFRAMING:
 367                         if (!capable(CAP_NET_ADMIN)) {
 368                                 error = -EPERM;
 369                                 goto done;
 370                         }
 371                         /* fall through */
 372                 default:
 373                         if (!dev->ops->ioctl) {
 374                                 error = -EINVAL;
 375                                 goto done;
 376                         }
 377                         size = dev->ops->ioctl(dev, cmd, buf);
 378                         if (size < 0) {
 379                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
 380                                 goto done;
 381                         }
 382         }
 383
 384         if (size)
 385                 error = put_user(size, &sioc->length)
 386                         ? -EFAULT : 0;
 387         else
 388                 error = 0;
 389 done:
 390         atm_dev_put(dev);
 391         return error;
 392 }
 393
 394 static __inline__ void *dev_get_idx(loff_t left)
 395 {
 396         struct list_head *p;
 397
 398         list_for_each(p, &atm_devs) {
 399                 if (!--left)
 400                         break;
 401         }
 402         return (p != &atm_devs) ? p : NULL;
 403 }
 404
 405 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
 406 {
 407         spin_lock(&atm_dev_lock);
 408         return *pos ? dev_get_idx(*pos) : (void *) 1;
 409 }
 410
 411 void atm_dev_seq_stop(struct seq_file *seq, void *v)
 412 {
 413         spin_unlock(&atm_dev_lock);
 414 }
 415
 416 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 417 {
 418         ++*pos;
 419         v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
 420         return (v == &atm_devs) ? NULL : v;
 421 }
 422
 423
 424 EXPORT_SYMBOL(atm_dev_register);
 425 EXPORT_SYMBOL(atm_dev_deregister);
 426 EXPORT_SYMBOL(atm_dev_lookup);
 427 EXPORT_SYMBOL(shutdown_atm_dev);