[NETLINK]: Directly return -EINTR from netlink_dump_start()
[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)
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                         mutex_lock(&atm_dev_mutex);
214                         list_for_each(p, &atm_devs)
215                                 size += sizeof(int);
216                         if (size > len) {
217                                 mutex_unlock(&atm_dev_mutex);
218                                 return -E2BIG;
219                         }
220                         tmp_buf = kmalloc(size, GFP_ATOMIC);
221                         if (!tmp_buf) {
222                                 mutex_unlock(&atm_dev_mutex);
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                         mutex_unlock(&atm_dev_mutex);
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 = try_then_request_module(atm_dev_lookup(number),
248                                             "atm-device-%d", number)))
249                 return -ENODEV;
250
251         switch (cmd) {
252                 case ATM_GETTYPE:
253                         size = strlen(dev->type) + 1;
254                         if (copy_to_user(buf, dev->type, size)) {
255                                 error = -EFAULT;
256                                 goto done;
257                         }
258                         break;
259                 case ATM_GETESI:
260                         size = ESI_LEN;
261                         if (copy_to_user(buf, dev->esi, size)) {
262                                 error = -EFAULT;
263                                 goto done;
264                         }
265                         break;
266                 case ATM_SETESI:
267                         {
268                                 int i;
269
270                                 for (i = 0; i < ESI_LEN; i++)
271                                         if (dev->esi[i]) {
272                                                 error = -EEXIST;
273                                                 goto done;
274                                         }
275                         }
276                         /* fall through */
277                 case ATM_SETESIF:
278                         {
279                                 unsigned char esi[ESI_LEN];
280
281                                 if (!capable(CAP_NET_ADMIN)) {
282                                         error = -EPERM;
283                                         goto done;
284                                 }
285                                 if (copy_from_user(esi, buf, ESI_LEN)) {
286                                         error = -EFAULT;
287                                         goto done;
288                                 }
289                                 memcpy(dev->esi, esi, ESI_LEN);
290                                 error =  ESI_LEN;
291                                 goto done;
292                         }
293                 case ATM_GETSTATZ:
294                         if (!capable(CAP_NET_ADMIN)) {
295                                 error = -EPERM;
296                                 goto done;
297                         }
298                         /* fall through */
299                 case ATM_GETSTAT:
300                         size = sizeof(struct atm_dev_stats);
301                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
302                         if (error)
303                                 goto done;
304                         break;
305                 case ATM_GETCIRANGE:
306                         size = sizeof(struct atm_cirange);
307                         if (copy_to_user(buf, &dev->ci_range, size)) {
308                                 error = -EFAULT;
309                                 goto done;
310                         }
311                         break;
312                 case ATM_GETLINKRATE:
313                         size = sizeof(int);
314                         if (copy_to_user(buf, &dev->link_rate, size)) {
315                                 error = -EFAULT;
316                                 goto done;
317                         }
318                         break;
319                 case ATM_RSTADDR:
320                         if (!capable(CAP_NET_ADMIN)) {
321                                 error = -EPERM;
322                                 goto done;
323                         }
324                         atm_reset_addr(dev, ATM_ADDR_LOCAL);
325                         break;
326                 case ATM_ADDADDR:
327                 case ATM_DELADDR:
328                 case ATM_ADDLECSADDR:
329                 case ATM_DELLECSADDR:
330                         if (!capable(CAP_NET_ADMIN)) {
331                                 error = -EPERM;
332                                 goto done;
333                         }
334                         {
335                                 struct sockaddr_atmsvc addr;
336
337                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
338                                         error = -EFAULT;
339                                         goto done;
340                                 }
341                                 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
342                                         error = atm_add_addr(dev, &addr,
343                                                              (cmd == ATM_ADDADDR ?
344                                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
345                                 else
346                                         error = atm_del_addr(dev, &addr,
347                                                              (cmd == ATM_DELADDR ?
348                                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
349                                 goto done;
350                         }
351                 case ATM_GETADDR:
352                 case ATM_GETLECSADDR:
353                         error = atm_get_addr(dev, buf, len,
354                                              (cmd == ATM_GETADDR ?
355                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
356                         if (error < 0)
357                                 goto done;
358                         size = error;
359                         /* may return 0, but later on size == 0 means "don't
360                            write the length" */
361                         error = put_user(size, &sioc->length)
362                                 ? -EFAULT : 0;
363                         goto done;
364                 case ATM_SETLOOP:
365                         if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
366                             __ATM_LM_XTLOC((int) (unsigned long) buf) >
367                             __ATM_LM_XTRMT((int) (unsigned long) buf)) {
368                                 error = -EINVAL;
369                                 goto done;
370                         }
371                         /* fall through */
372                 case ATM_SETCIRANGE:
373                 case SONET_GETSTATZ:
374                 case SONET_SETDIAG:
375                 case SONET_CLRDIAG:
376                 case SONET_SETFRAMING:
377                         if (!capable(CAP_NET_ADMIN)) {
378                                 error = -EPERM;
379                                 goto done;
380                         }
381                         /* fall through */
382                 default:
383                         if (!dev->ops->ioctl) {
384                                 error = -EINVAL;
385                                 goto done;
386                         }
387                         size = dev->ops->ioctl(dev, cmd, buf);
388                         if (size < 0) {
389                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
390                                 goto done;
391                         }
392         }
393
394         if (size)
395                 error = put_user(size, &sioc->length)
396                         ? -EFAULT : 0;
397         else
398                 error = 0;
399 done:
400         atm_dev_put(dev);
401         return error;
402 }
403
404 static __inline__ void *dev_get_idx(loff_t left)
405 {
406         struct list_head *p;
407
408         list_for_each(p, &atm_devs) {
409                 if (!--left)
410                         break;
411         }
412         return (p != &atm_devs) ? p : NULL;
413 }
414
415 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
416 {
417         mutex_lock(&atm_dev_mutex);
418         return *pos ? dev_get_idx(*pos) : (void *) 1;
419 }
420
421 void atm_dev_seq_stop(struct seq_file *seq, void *v)
422 {
423         mutex_unlock(&atm_dev_mutex);
424 }
425
426 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
427 {
428         ++*pos;
429         v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
430         return (v == &atm_devs) ? NULL : v;
431 }
432
433
434 EXPORT_SYMBOL(atm_dev_register);
435 EXPORT_SYMBOL(atm_dev_deregister);
436 EXPORT_SYMBOL(atm_dev_lookup);