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resources.c
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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 <[email protected]>
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 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
11 
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/capability.h>
20 #include <linux/delay.h>
21 #include <linux/mutex.h>
22 #include <linux/slab.h>
23 
24 #include <net/sock.h> /* for struct sock */
25 
26 #include "common.h"
27 #include "resources.h"
28 #include "addr.h"
29 
30 
31 LIST_HEAD(atm_devs);
32 DEFINE_MUTEX(atm_dev_mutex);
33 
34 static struct atm_dev *__alloc_atm_dev(const char *type)
35 {
36  struct atm_dev *dev;
37 
38  dev = kzalloc(sizeof(*dev), GFP_KERNEL);
39  if (!dev)
40  return NULL;
41  dev->type = type;
42  dev->signal = ATM_PHY_SIG_UNKNOWN;
43  dev->link_rate = ATM_OC3_PCR;
44  spin_lock_init(&dev->lock);
45  INIT_LIST_HEAD(&dev->local);
46  INIT_LIST_HEAD(&dev->lecs);
47 
48  return dev;
49 }
50 
51 static struct atm_dev *__atm_dev_lookup(int number)
52 {
53  struct atm_dev *dev;
54  struct list_head *p;
55 
56  list_for_each(p, &atm_devs) {
57  dev = list_entry(p, struct atm_dev, dev_list);
58  if (dev->number == number) {
59  atm_dev_hold(dev);
60  return dev;
61  }
62  }
63  return NULL;
64 }
65 
66 struct atm_dev *atm_dev_lookup(int number)
67 {
68  struct atm_dev *dev;
69 
70  mutex_lock(&atm_dev_mutex);
71  dev = __atm_dev_lookup(number);
72  mutex_unlock(&atm_dev_mutex);
73  return dev;
74 }
75 EXPORT_SYMBOL(atm_dev_lookup);
76 
77 struct atm_dev *atm_dev_register(const char *type, struct device *parent,
78  const struct atmdev_ops *ops, int number,
79  unsigned long *flags)
80 {
81  struct atm_dev *dev, *inuse;
82 
83  dev = __alloc_atm_dev(type);
84  if (!dev) {
85  pr_err("no space for dev %s\n", type);
86  return NULL;
87  }
88  mutex_lock(&atm_dev_mutex);
89  if (number != -1) {
90  inuse = __atm_dev_lookup(number);
91  if (inuse) {
92  atm_dev_put(inuse);
93  mutex_unlock(&atm_dev_mutex);
94  kfree(dev);
95  return NULL;
96  }
97  dev->number = number;
98  } else {
99  dev->number = 0;
100  while ((inuse = __atm_dev_lookup(dev->number))) {
101  atm_dev_put(inuse);
102  dev->number++;
103  }
104  }
105 
106  dev->ops = ops;
107  if (flags)
108  dev->flags = *flags;
109  else
110  memset(&dev->flags, 0, sizeof(dev->flags));
111  memset(&dev->stats, 0, sizeof(dev->stats));
112  atomic_set(&dev->refcnt, 1);
113 
114  if (atm_proc_dev_register(dev) < 0) {
115  pr_err("atm_proc_dev_register failed for dev %s\n", type);
116  goto out_fail;
117  }
118 
119  if (atm_register_sysfs(dev, parent) < 0) {
120  pr_err("atm_register_sysfs failed for dev %s\n", type);
121  atm_proc_dev_deregister(dev);
122  goto out_fail;
123  }
124 
125  list_add_tail(&dev->dev_list, &atm_devs);
126 
127 out:
128  mutex_unlock(&atm_dev_mutex);
129  return dev;
130 
131 out_fail:
132  kfree(dev);
133  dev = NULL;
134  goto out;
135 }
136 EXPORT_SYMBOL(atm_dev_register);
137 
138 void atm_dev_deregister(struct atm_dev *dev)
139 {
140  BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
141  set_bit(ATM_DF_REMOVED, &dev->flags);
142 
143  /*
144  * if we remove current device from atm_devs list, new device
145  * with same number can appear, such we need deregister proc,
146  * release async all vccs and remove them from vccs list too
147  */
148  mutex_lock(&atm_dev_mutex);
149  list_del(&dev->dev_list);
150  mutex_unlock(&atm_dev_mutex);
151 
152  atm_dev_release_vccs(dev);
153  atm_unregister_sysfs(dev);
154  atm_proc_dev_deregister(dev);
155 
156  atm_dev_put(dev);
157 }
158 EXPORT_SYMBOL(atm_dev_deregister);
159 
160 static void copy_aal_stats(struct k_atm_aal_stats *from,
161  struct atm_aal_stats *to)
162 {
163 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
164  __AAL_STAT_ITEMS
165 #undef __HANDLE_ITEM
166 }
167 
168 static void subtract_aal_stats(struct k_atm_aal_stats *from,
169  struct atm_aal_stats *to)
170 {
171 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
172  __AAL_STAT_ITEMS
173 #undef __HANDLE_ITEM
174 }
175 
176 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg,
177  int zero)
178 {
179  struct atm_dev_stats tmp;
180  int error = 0;
181 
182  copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
183  copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
184  copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
185  if (arg)
186  error = copy_to_user(arg, &tmp, sizeof(tmp));
187  if (zero && !error) {
188  subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
189  subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
190  subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
191  }
192  return error ? -EFAULT : 0;
193 }
194 
195 int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat)
196 {
197  void __user *buf;
198  int error, len, number, size = 0;
199  struct atm_dev *dev;
200  struct list_head *p;
201  int *tmp_buf, *tmp_p;
202  int __user *sioc_len;
203  int __user *iobuf_len;
204 
205 #ifndef CONFIG_COMPAT
206  compat = 0; /* Just so the compiler _knows_ */
207 #endif
208 
209  switch (cmd) {
210  case ATM_GETNAMES:
211  if (compat) {
212 #ifdef CONFIG_COMPAT
213  struct compat_atm_iobuf __user *ciobuf = arg;
214  compat_uptr_t cbuf;
215  iobuf_len = &ciobuf->length;
216  if (get_user(cbuf, &ciobuf->buffer))
217  return -EFAULT;
218  buf = compat_ptr(cbuf);
219 #endif
220  } else {
221  struct atm_iobuf __user *iobuf = arg;
222  iobuf_len = &iobuf->length;
223  if (get_user(buf, &iobuf->buffer))
224  return -EFAULT;
225  }
226  if (get_user(len, iobuf_len))
227  return -EFAULT;
228  mutex_lock(&atm_dev_mutex);
229  list_for_each(p, &atm_devs)
230  size += sizeof(int);
231  if (size > len) {
232  mutex_unlock(&atm_dev_mutex);
233  return -E2BIG;
234  }
235  tmp_buf = kmalloc(size, GFP_ATOMIC);
236  if (!tmp_buf) {
237  mutex_unlock(&atm_dev_mutex);
238  return -ENOMEM;
239  }
240  tmp_p = tmp_buf;
241  list_for_each(p, &atm_devs) {
242  dev = list_entry(p, struct atm_dev, dev_list);
243  *tmp_p++ = dev->number;
244  }
245  mutex_unlock(&atm_dev_mutex);
246  error = ((copy_to_user(buf, tmp_buf, size)) ||
247  put_user(size, iobuf_len))
248  ? -EFAULT : 0;
249  kfree(tmp_buf);
250  return error;
251  default:
252  break;
253  }
254 
255  if (compat) {
256 #ifdef CONFIG_COMPAT
257  struct compat_atmif_sioc __user *csioc = arg;
258  compat_uptr_t carg;
259 
260  sioc_len = &csioc->length;
261  if (get_user(carg, &csioc->arg))
262  return -EFAULT;
263  buf = compat_ptr(carg);
264 
265  if (get_user(len, &csioc->length))
266  return -EFAULT;
267  if (get_user(number, &csioc->number))
268  return -EFAULT;
269 #endif
270  } else {
271  struct atmif_sioc __user *sioc = arg;
272 
273  sioc_len = &sioc->length;
274  if (get_user(buf, &sioc->arg))
275  return -EFAULT;
276  if (get_user(len, &sioc->length))
277  return -EFAULT;
278  if (get_user(number, &sioc->number))
279  return -EFAULT;
280  }
281 
282  dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
283  number);
284  if (!dev)
285  return -ENODEV;
286 
287  switch (cmd) {
288  case ATM_GETTYPE:
289  size = strlen(dev->type) + 1;
290  if (copy_to_user(buf, dev->type, size)) {
291  error = -EFAULT;
292  goto done;
293  }
294  break;
295  case ATM_GETESI:
296  size = ESI_LEN;
297  if (copy_to_user(buf, dev->esi, size)) {
298  error = -EFAULT;
299  goto done;
300  }
301  break;
302  case ATM_SETESI:
303  {
304  int i;
305 
306  for (i = 0; i < ESI_LEN; i++)
307  if (dev->esi[i]) {
308  error = -EEXIST;
309  goto done;
310  }
311  }
312  /* fall through */
313  case ATM_SETESIF:
314  {
315  unsigned char esi[ESI_LEN];
316 
317  if (!capable(CAP_NET_ADMIN)) {
318  error = -EPERM;
319  goto done;
320  }
321  if (copy_from_user(esi, buf, ESI_LEN)) {
322  error = -EFAULT;
323  goto done;
324  }
325  memcpy(dev->esi, esi, ESI_LEN);
326  error = ESI_LEN;
327  goto done;
328  }
329  case ATM_GETSTATZ:
330  if (!capable(CAP_NET_ADMIN)) {
331  error = -EPERM;
332  goto done;
333  }
334  /* fall through */
335  case ATM_GETSTAT:
336  size = sizeof(struct atm_dev_stats);
337  error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
338  if (error)
339  goto done;
340  break;
341  case ATM_GETCIRANGE:
342  size = sizeof(struct atm_cirange);
343  if (copy_to_user(buf, &dev->ci_range, size)) {
344  error = -EFAULT;
345  goto done;
346  }
347  break;
348  case ATM_GETLINKRATE:
349  size = sizeof(int);
350  if (copy_to_user(buf, &dev->link_rate, size)) {
351  error = -EFAULT;
352  goto done;
353  }
354  break;
355  case ATM_RSTADDR:
356  if (!capable(CAP_NET_ADMIN)) {
357  error = -EPERM;
358  goto done;
359  }
360  atm_reset_addr(dev, ATM_ADDR_LOCAL);
361  break;
362  case ATM_ADDADDR:
363  case ATM_DELADDR:
364  case ATM_ADDLECSADDR:
365  case ATM_DELLECSADDR:
366  {
367  struct sockaddr_atmsvc addr;
368 
369  if (!capable(CAP_NET_ADMIN)) {
370  error = -EPERM;
371  goto done;
372  }
373 
374  if (copy_from_user(&addr, buf, sizeof(addr))) {
375  error = -EFAULT;
376  goto done;
377  }
378  if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
379  error = atm_add_addr(dev, &addr,
380  (cmd == ATM_ADDADDR ?
381  ATM_ADDR_LOCAL : ATM_ADDR_LECS));
382  else
383  error = atm_del_addr(dev, &addr,
384  (cmd == ATM_DELADDR ?
385  ATM_ADDR_LOCAL : ATM_ADDR_LECS));
386  goto done;
387  }
388  case ATM_GETADDR:
389  case ATM_GETLECSADDR:
390  error = atm_get_addr(dev, buf, len,
391  (cmd == ATM_GETADDR ?
392  ATM_ADDR_LOCAL : ATM_ADDR_LECS));
393  if (error < 0)
394  goto done;
395  size = error;
396  /* may return 0, but later on size == 0 means "don't
397  write the length" */
398  error = put_user(size, sioc_len) ? -EFAULT : 0;
399  goto done;
400  case ATM_SETLOOP:
401  if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
402  __ATM_LM_XTLOC((int) (unsigned long) buf) >
403  __ATM_LM_XTRMT((int) (unsigned long) buf)) {
404  error = -EINVAL;
405  goto done;
406  }
407  /* fall through */
408  case ATM_SETCIRANGE:
409  case SONET_GETSTATZ:
410  case SONET_SETDIAG:
411  case SONET_CLRDIAG:
412  case SONET_SETFRAMING:
413  if (!capable(CAP_NET_ADMIN)) {
414  error = -EPERM;
415  goto done;
416  }
417  /* fall through */
418  default:
419  if (compat) {
420 #ifdef CONFIG_COMPAT
421  if (!dev->ops->compat_ioctl) {
422  error = -EINVAL;
423  goto done;
424  }
425  size = dev->ops->compat_ioctl(dev, cmd, buf);
426 #endif
427  } else {
428  if (!dev->ops->ioctl) {
429  error = -EINVAL;
430  goto done;
431  }
432  size = dev->ops->ioctl(dev, cmd, buf);
433  }
434  if (size < 0) {
435  error = (size == -ENOIOCTLCMD ? -ENOTTY : size);
436  goto done;
437  }
438  }
439 
440  if (size)
441  error = put_user(size, sioc_len) ? -EFAULT : 0;
442  else
443  error = 0;
444 done:
445  atm_dev_put(dev);
446  return error;
447 }
448 
449 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
450 {
451  mutex_lock(&atm_dev_mutex);
452  return seq_list_start_head(&atm_devs, *pos);
453 }
454 
455 void atm_dev_seq_stop(struct seq_file *seq, void *v)
456 {
457  mutex_unlock(&atm_dev_mutex);
458 }
459 
460 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
461 {
462  return seq_list_next(v, &atm_devs, pos);
463 }
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