libertas: pos[4] tested twice, 2nd should be pos[5]
[linux-2.6] / 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/ctype.h>
12 #include <linux/string.h>
13 #include <linux/atmdev.h>
14 #include <linux/sonet.h>
15 #include <linux/kernel.h> /* for barrier */
16 #include <linux/module.h>
17 #include <linux/bitops.h>
18 #include <linux/capability.h>
19 #include <linux/delay.h>
20 #include <linux/mutex.h>
21
22 #include <net/sock.h>    /* for struct sock */
23
24 #include "common.h"
25 #include "resources.h"
26 #include "addr.h"
27
28
29 LIST_HEAD(atm_devs);
30 DEFINE_MUTEX(atm_dev_mutex);
31
32 static struct atm_dev *__alloc_atm_dev(const char *type)
33 {
34         struct atm_dev *dev;
35
36         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
37         if (!dev)
38                 return NULL;
39         dev->type = type;
40         dev->signal = ATM_PHY_SIG_UNKNOWN;
41         dev->link_rate = ATM_OC3_PCR;
42         spin_lock_init(&dev->lock);
43         INIT_LIST_HEAD(&dev->local);
44         INIT_LIST_HEAD(&dev->lecs);
45
46         return dev;
47 }
48
49 static struct atm_dev *__atm_dev_lookup(int number)
50 {
51         struct atm_dev *dev;
52         struct list_head *p;
53
54         list_for_each(p, &atm_devs) {
55                 dev = list_entry(p, struct atm_dev, dev_list);
56                 if (dev->number == number) {
57                         atm_dev_hold(dev);
58                         return dev;
59                 }
60         }
61         return NULL;
62 }
63
64 struct atm_dev *atm_dev_lookup(int number)
65 {
66         struct atm_dev *dev;
67
68         mutex_lock(&atm_dev_mutex);
69         dev = __atm_dev_lookup(number);
70         mutex_unlock(&atm_dev_mutex);
71         return dev;
72 }
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         mutex_lock(&atm_dev_mutex);
87         if (number != -1) {
88                 if ((inuse = __atm_dev_lookup(number))) {
89                         atm_dev_put(inuse);
90                         mutex_unlock(&atm_dev_mutex);
91                         kfree(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
111         if (atm_proc_dev_register(dev) < 0) {
112                 printk(KERN_ERR "atm_dev_register: "
113                        "atm_proc_dev_register failed for dev %s\n",
114                        type);
115                 goto out_fail;
116         }
117
118         if (atm_register_sysfs(dev) < 0) {
119                 printk(KERN_ERR "atm_dev_register: "
120                        "atm_register_sysfs failed for dev %s\n",
121                        type);
122                 atm_proc_dev_deregister(dev);
123                 goto out_fail;
124         }
125
126         list_add_tail(&dev->dev_list, &atm_devs);
127
128 out:
129         mutex_unlock(&atm_dev_mutex);
130         return dev;
131
132 out_fail:
133         kfree(dev);
134         dev = NULL;
135         goto out;
136 }
137
138
139 void atm_dev_deregister(struct atm_dev *dev)
140 {
141         BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
142         set_bit(ATM_DF_REMOVED, &dev->flags);
143
144         /*
145          * if we remove current device from atm_devs list, new device
146          * with same number can appear, such we need deregister proc,
147          * release async all vccs and remove them from vccs list too
148          */
149         mutex_lock(&atm_dev_mutex);
150         list_del(&dev->dev_list);
151         mutex_unlock(&atm_dev_mutex);
152
153         atm_dev_release_vccs(dev);
154         atm_unregister_sysfs(dev);
155         atm_proc_dev_deregister(dev);
156
157         atm_dev_put(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, int compat)
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         int __user *sioc_len;
206         int __user *iobuf_len;
207
208 #ifndef CONFIG_COMPAT
209         compat = 0; /* Just so the compiler _knows_ */
210 #endif
211
212         switch (cmd) {
213                 case ATM_GETNAMES:
214
215                         if (compat) {
216 #ifdef CONFIG_COMPAT
217                                 struct compat_atm_iobuf __user *ciobuf = arg;
218                                 compat_uptr_t cbuf;
219                                 iobuf_len = &ciobuf->length;
220                                 if (get_user(cbuf, &ciobuf->buffer))
221                                         return -EFAULT;
222                                 buf = compat_ptr(cbuf);
223 #endif
224                         } else {
225                                 struct atm_iobuf __user *iobuf = arg;
226                                 iobuf_len = &iobuf->length;
227                                 if (get_user(buf, &iobuf->buffer))
228                                         return -EFAULT;
229                         }
230                         if (get_user(len, iobuf_len))
231                                 return -EFAULT;
232                         mutex_lock(&atm_dev_mutex);
233                         list_for_each(p, &atm_devs)
234                                 size += sizeof(int);
235                         if (size > len) {
236                                 mutex_unlock(&atm_dev_mutex);
237                                 return -E2BIG;
238                         }
239                         tmp_buf = kmalloc(size, GFP_ATOMIC);
240                         if (!tmp_buf) {
241                                 mutex_unlock(&atm_dev_mutex);
242                                 return -ENOMEM;
243                         }
244                         tmp_p = tmp_buf;
245                         list_for_each(p, &atm_devs) {
246                                 dev = list_entry(p, struct atm_dev, dev_list);
247                                 *tmp_p++ = dev->number;
248                         }
249                         mutex_unlock(&atm_dev_mutex);
250                         error = ((copy_to_user(buf, tmp_buf, size)) ||
251                                         put_user(size, iobuf_len))
252                                                 ? -EFAULT : 0;
253                         kfree(tmp_buf);
254                         return error;
255                 default:
256                         break;
257         }
258
259         if (compat) {
260 #ifdef CONFIG_COMPAT
261                 struct compat_atmif_sioc __user *csioc = arg;
262                 compat_uptr_t carg;
263
264                 sioc_len = &csioc->length;
265                 if (get_user(carg, &csioc->arg))
266                         return -EFAULT;
267                 buf = compat_ptr(carg);
268
269                 if (get_user(len, &csioc->length))
270                         return -EFAULT;
271                 if (get_user(number, &csioc->number))
272                         return -EFAULT;
273 #endif
274         } else {
275                 struct atmif_sioc __user *sioc = arg;
276
277                 sioc_len = &sioc->length;
278                 if (get_user(buf, &sioc->arg))
279                         return -EFAULT;
280                 if (get_user(len, &sioc->length))
281                         return -EFAULT;
282                 if (get_user(number, &sioc->number))
283                         return -EFAULT;
284         }
285         if (!(dev = try_then_request_module(atm_dev_lookup(number),
286                                             "atm-device-%d", number)))
287                 return -ENODEV;
288
289         switch (cmd) {
290                 case ATM_GETTYPE:
291                         size = strlen(dev->type) + 1;
292                         if (copy_to_user(buf, dev->type, size)) {
293                                 error = -EFAULT;
294                                 goto done;
295                         }
296                         break;
297                 case ATM_GETESI:
298                         size = ESI_LEN;
299                         if (copy_to_user(buf, dev->esi, size)) {
300                                 error = -EFAULT;
301                                 goto done;
302                         }
303                         break;
304                 case ATM_SETESI:
305                         {
306                                 int i;
307
308                                 for (i = 0; i < ESI_LEN; i++)
309                                         if (dev->esi[i]) {
310                                                 error = -EEXIST;
311                                                 goto done;
312                                         }
313                         }
314                         /* fall through */
315                 case ATM_SETESIF:
316                         {
317                                 unsigned char esi[ESI_LEN];
318
319                                 if (!capable(CAP_NET_ADMIN)) {
320                                         error = -EPERM;
321                                         goto done;
322                                 }
323                                 if (copy_from_user(esi, buf, ESI_LEN)) {
324                                         error = -EFAULT;
325                                         goto done;
326                                 }
327                                 memcpy(dev->esi, esi, ESI_LEN);
328                                 error =  ESI_LEN;
329                                 goto done;
330                         }
331                 case ATM_GETSTATZ:
332                         if (!capable(CAP_NET_ADMIN)) {
333                                 error = -EPERM;
334                                 goto done;
335                         }
336                         /* fall through */
337                 case ATM_GETSTAT:
338                         size = sizeof(struct atm_dev_stats);
339                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
340                         if (error)
341                                 goto done;
342                         break;
343                 case ATM_GETCIRANGE:
344                         size = sizeof(struct atm_cirange);
345                         if (copy_to_user(buf, &dev->ci_range, size)) {
346                                 error = -EFAULT;
347                                 goto done;
348                         }
349                         break;
350                 case ATM_GETLINKRATE:
351                         size = sizeof(int);
352                         if (copy_to_user(buf, &dev->link_rate, size)) {
353                                 error = -EFAULT;
354                                 goto done;
355                         }
356                         break;
357                 case ATM_RSTADDR:
358                         if (!capable(CAP_NET_ADMIN)) {
359                                 error = -EPERM;
360                                 goto done;
361                         }
362                         atm_reset_addr(dev, ATM_ADDR_LOCAL);
363                         break;
364                 case ATM_ADDADDR:
365                 case ATM_DELADDR:
366                 case ATM_ADDLECSADDR:
367                 case ATM_DELLECSADDR:
368                         if (!capable(CAP_NET_ADMIN)) {
369                                 error = -EPERM;
370                                 goto done;
371                         }
372                         {
373                                 struct sockaddr_atmsvc addr;
374
375                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
376                                         error = -EFAULT;
377                                         goto done;
378                                 }
379                                 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
380                                         error = atm_add_addr(dev, &addr,
381                                                              (cmd == ATM_ADDADDR ?
382                                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
383                                 else
384                                         error = atm_del_addr(dev, &addr,
385                                                              (cmd == ATM_DELADDR ?
386                                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
387                                 goto done;
388                         }
389                 case ATM_GETADDR:
390                 case ATM_GETLECSADDR:
391                         error = atm_get_addr(dev, buf, len,
392                                              (cmd == ATM_GETADDR ?
393                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
394                         if (error < 0)
395                                 goto done;
396                         size = error;
397                         /* may return 0, but later on size == 0 means "don't
398                            write the length" */
399                         error = put_user(size, sioc_len)
400                                 ? -EFAULT : 0;
401                         goto done;
402                 case ATM_SETLOOP:
403                         if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
404                             __ATM_LM_XTLOC((int) (unsigned long) buf) >
405                             __ATM_LM_XTRMT((int) (unsigned long) buf)) {
406                                 error = -EINVAL;
407                                 goto done;
408                         }
409                         /* fall through */
410                 case ATM_SETCIRANGE:
411                 case SONET_GETSTATZ:
412                 case SONET_SETDIAG:
413                 case SONET_CLRDIAG:
414                 case SONET_SETFRAMING:
415                         if (!capable(CAP_NET_ADMIN)) {
416                                 error = -EPERM;
417                                 goto done;
418                         }
419                         /* fall through */
420                 default:
421                         if (compat) {
422 #ifdef CONFIG_COMPAT
423                                 if (!dev->ops->compat_ioctl) {
424                                         error = -EINVAL;
425                                         goto done;
426                                 }
427                                 size = dev->ops->compat_ioctl(dev, cmd, buf);
428 #endif
429                         } else {
430                                 if (!dev->ops->ioctl) {
431                                         error = -EINVAL;
432                                         goto done;
433                                 }
434                                 size = dev->ops->ioctl(dev, cmd, buf);
435                         }
436                         if (size < 0) {
437                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
438                                 goto done;
439                         }
440         }
441
442         if (size)
443                 error = put_user(size, sioc_len)
444                         ? -EFAULT : 0;
445         else
446                 error = 0;
447 done:
448         atm_dev_put(dev);
449         return error;
450 }
451
452 static __inline__ void *dev_get_idx(loff_t left)
453 {
454         struct list_head *p;
455
456         list_for_each(p, &atm_devs) {
457                 if (!--left)
458                         break;
459         }
460         return (p != &atm_devs) ? p : NULL;
461 }
462
463 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
464 {
465         mutex_lock(&atm_dev_mutex);
466         return *pos ? dev_get_idx(*pos) : SEQ_START_TOKEN;
467 }
468
469 void atm_dev_seq_stop(struct seq_file *seq, void *v)
470 {
471         mutex_unlock(&atm_dev_mutex);
472 }
473
474 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
475 {
476         ++*pos;
477         v = (v == SEQ_START_TOKEN)
478                 ? atm_devs.next : ((struct list_head *)v)->next;
479         return (v == &atm_devs) ? NULL : v;
480 }
481
482
483 EXPORT_SYMBOL(atm_dev_register);
484 EXPORT_SYMBOL(atm_dev_deregister);
485 EXPORT_SYMBOL(atm_dev_lookup);