[ATM]: attempt to autoload atm drivers
[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/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         INIT_LIST_HEAD(&dev->lecs);
44
45         return 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, unsigned long *flags)
75 {
76         struct atm_dev *dev, *inuse;
77
78         dev = __alloc_atm_dev(type);
79         if (!dev) {
80                 printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
81                     type);
82                 return NULL;
83         }
84         spin_lock(&atm_dev_lock);
85         if (number != -1) {
86                 if ((inuse = __atm_dev_lookup(number))) {
87                         atm_dev_put(inuse);
88                         spin_unlock(&atm_dev_lock);
89                         kfree(dev);
90                         return NULL;
91                 }
92                 dev->number = number;
93         } else {
94                 dev->number = 0;
95                 while ((inuse = __atm_dev_lookup(dev->number))) {
96                         atm_dev_put(inuse);
97                         dev->number++;
98                 }
99         }
100
101         dev->ops = ops;
102         if (flags)
103                 dev->flags = *flags;
104         else
105                 memset(&dev->flags, 0, sizeof(dev->flags));
106         memset(&dev->stats, 0, sizeof(dev->stats));
107         atomic_set(&dev->refcnt, 1);
108         list_add_tail(&dev->dev_list, &atm_devs);
109         spin_unlock(&atm_dev_lock);
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                 spin_lock(&atm_dev_lock);
116                 list_del(&dev->dev_list);
117                 spin_unlock(&atm_dev_lock);
118                 kfree(dev);
119                 return NULL;
120         }
121
122         return dev;
123 }
124
125
126 void atm_dev_deregister(struct atm_dev *dev)
127 {
128         unsigned long warning_time;
129
130         atm_proc_dev_deregister(dev);
131
132         spin_lock(&atm_dev_lock);
133         list_del(&dev->dev_list);
134         spin_unlock(&atm_dev_lock);
135
136         warning_time = jiffies;
137         while (atomic_read(&dev->refcnt) != 1) {
138                 msleep(250);
139                 if ((jiffies - warning_time) > 10 * HZ) {
140                         printk(KERN_EMERG "atm_dev_deregister: waiting for "
141                                "dev %d to become free. Usage count = %d\n",
142                                dev->number, atomic_read(&dev->refcnt));
143                         warning_time = jiffies;
144                 }
145         }
146
147         kfree(dev);
148 }
149
150 void shutdown_atm_dev(struct atm_dev *dev)
151 {
152         if (atomic_read(&dev->refcnt) > 1) {
153                 set_bit(ATM_DF_CLOSE, &dev->flags);
154                 return;
155         }
156         if (dev->ops->dev_close)
157                 dev->ops->dev_close(dev);
158         atm_dev_deregister(dev);
159 }
160
161
162 static void copy_aal_stats(struct k_atm_aal_stats *from,
163     struct atm_aal_stats *to)
164 {
165 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
166         __AAL_STAT_ITEMS
167 #undef __HANDLE_ITEM
168 }
169
170
171 static void subtract_aal_stats(struct k_atm_aal_stats *from,
172     struct atm_aal_stats *to)
173 {
174 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
175         __AAL_STAT_ITEMS
176 #undef __HANDLE_ITEM
177 }
178
179
180 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
181 {
182         struct atm_dev_stats tmp;
183         int error = 0;
184
185         copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
186         copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
187         copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
188         if (arg)
189                 error = copy_to_user(arg, &tmp, sizeof(tmp));
190         if (zero && !error) {
191                 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
192                 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
193                 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
194         }
195         return error ? -EFAULT : 0;
196 }
197
198
199 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
200 {
201         void __user *buf;
202         int error, len, number, size = 0;
203         struct atm_dev *dev;
204         struct list_head *p;
205         int *tmp_buf, *tmp_p;
206         struct atm_iobuf __user *iobuf = arg;
207         struct atmif_sioc __user *sioc = arg;
208         switch (cmd) {
209                 case ATM_GETNAMES:
210                         if (get_user(buf, &iobuf->buffer))
211                                 return -EFAULT;
212                         if (get_user(len, &iobuf->length))
213                                 return -EFAULT;
214                         spin_lock(&atm_dev_lock);
215                         list_for_each(p, &atm_devs)
216                                 size += sizeof(int);
217                         if (size > len) {
218                                 spin_unlock(&atm_dev_lock);
219                                 return -E2BIG;
220                         }
221                         tmp_buf = kmalloc(size, GFP_ATOMIC);
222                         if (!tmp_buf) {
223                                 spin_unlock(&atm_dev_lock);
224                                 return -ENOMEM;
225                         }
226                         tmp_p = tmp_buf;
227                         list_for_each(p, &atm_devs) {
228                                 dev = list_entry(p, struct atm_dev, dev_list);
229                                 *tmp_p++ = dev->number;
230                         }
231                         spin_unlock(&atm_dev_lock);
232                         error = ((copy_to_user(buf, tmp_buf, size)) ||
233                                         put_user(size, &iobuf->length))
234                                                 ? -EFAULT : 0;
235                         kfree(tmp_buf);
236                         return error;
237                 default:
238                         break;
239         }
240
241         if (get_user(buf, &sioc->arg))
242                 return -EFAULT;
243         if (get_user(len, &sioc->length))
244                 return -EFAULT;
245         if (get_user(number, &sioc->number))
246                 return -EFAULT;
247
248         if (!(dev = try_then_request_module(atm_dev_lookup(number),
249                                             "atm-device-%d", number)))
250                 return -ENODEV;
251         
252         switch (cmd) {
253                 case ATM_GETTYPE:
254                         size = strlen(dev->type) + 1;
255                         if (copy_to_user(buf, dev->type, size)) {
256                                 error = -EFAULT;
257                                 goto done;
258                         }
259                         break;
260                 case ATM_GETESI:
261                         size = ESI_LEN;
262                         if (copy_to_user(buf, dev->esi, size)) {
263                                 error = -EFAULT;
264                                 goto done;
265                         }
266                         break;
267                 case ATM_SETESI:
268                         {
269                                 int i;
270
271                                 for (i = 0; i < ESI_LEN; i++)
272                                         if (dev->esi[i]) {
273                                                 error = -EEXIST;
274                                                 goto done;
275                                         }
276                         }
277                         /* fall through */
278                 case ATM_SETESIF:
279                         {
280                                 unsigned char esi[ESI_LEN];
281
282                                 if (!capable(CAP_NET_ADMIN)) {
283                                         error = -EPERM;
284                                         goto done;
285                                 }
286                                 if (copy_from_user(esi, buf, ESI_LEN)) {
287                                         error = -EFAULT;
288                                         goto done;
289                                 }
290                                 memcpy(dev->esi, esi, ESI_LEN);
291                                 error =  ESI_LEN;
292                                 goto done;
293                         }
294                 case ATM_GETSTATZ:
295                         if (!capable(CAP_NET_ADMIN)) {
296                                 error = -EPERM;
297                                 goto done;
298                         }
299                         /* fall through */
300                 case ATM_GETSTAT:
301                         size = sizeof(struct atm_dev_stats);
302                         error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
303                         if (error)
304                                 goto done;
305                         break;
306                 case ATM_GETCIRANGE:
307                         size = sizeof(struct atm_cirange);
308                         if (copy_to_user(buf, &dev->ci_range, size)) {
309                                 error = -EFAULT;
310                                 goto done;
311                         }
312                         break;
313                 case ATM_GETLINKRATE:
314                         size = sizeof(int);
315                         if (copy_to_user(buf, &dev->link_rate, size)) {
316                                 error = -EFAULT;
317                                 goto done;
318                         }
319                         break;
320                 case ATM_RSTADDR:
321                         if (!capable(CAP_NET_ADMIN)) {
322                                 error = -EPERM;
323                                 goto done;
324                         }
325                         atm_reset_addr(dev, ATM_ADDR_LOCAL);
326                         break;
327                 case ATM_ADDADDR:
328                 case ATM_DELADDR:
329                 case ATM_ADDLECSADDR:
330                 case ATM_DELLECSADDR:
331                         if (!capable(CAP_NET_ADMIN)) {
332                                 error = -EPERM;
333                                 goto done;
334                         }
335                         {
336                                 struct sockaddr_atmsvc addr;
337
338                                 if (copy_from_user(&addr, buf, sizeof(addr))) {
339                                         error = -EFAULT;
340                                         goto done;
341                                 }
342                                 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
343                                         error = atm_add_addr(dev, &addr,
344                                                              (cmd == ATM_ADDADDR ?
345                                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
346                                 else
347                                         error = atm_del_addr(dev, &addr,
348                                                              (cmd == ATM_DELADDR ?
349                                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
350                                 goto done;
351                         }
352                 case ATM_GETADDR:
353                 case ATM_GETLECSADDR:
354                         error = atm_get_addr(dev, buf, len,
355                                              (cmd == ATM_GETADDR ?
356                                               ATM_ADDR_LOCAL : ATM_ADDR_LECS));
357                         if (error < 0)
358                                 goto done;
359                         size = error;
360                         /* may return 0, but later on size == 0 means "don't
361                            write the length" */
362                         error = put_user(size, &sioc->length)
363                                 ? -EFAULT : 0;
364                         goto done;
365                 case ATM_SETLOOP:
366                         if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
367                             __ATM_LM_XTLOC((int) (unsigned long) buf) >
368                             __ATM_LM_XTRMT((int) (unsigned long) buf)) {
369                                 error = -EINVAL;
370                                 goto done;
371                         }
372                         /* fall through */
373                 case ATM_SETCIRANGE:
374                 case SONET_GETSTATZ:
375                 case SONET_SETDIAG:
376                 case SONET_CLRDIAG:
377                 case SONET_SETFRAMING:
378                         if (!capable(CAP_NET_ADMIN)) {
379                                 error = -EPERM;
380                                 goto done;
381                         }
382                         /* fall through */
383                 default:
384                         if (!dev->ops->ioctl) {
385                                 error = -EINVAL;
386                                 goto done;
387                         }
388                         size = dev->ops->ioctl(dev, cmd, buf);
389                         if (size < 0) {
390                                 error = (size == -ENOIOCTLCMD ? -EINVAL : size);
391                                 goto done;
392                         }
393         }
394         
395         if (size)
396                 error = put_user(size, &sioc->length)
397                         ? -EFAULT : 0;
398         else
399                 error = 0;
400 done:
401         atm_dev_put(dev);
402         return error;
403 }
404
405 static __inline__ void *dev_get_idx(loff_t left)
406 {
407         struct list_head *p;
408
409         list_for_each(p, &atm_devs) {
410                 if (!--left)
411                         break;
412         }
413         return (p != &atm_devs) ? p : NULL;
414 }
415
416 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
417 {
418         spin_lock(&atm_dev_lock);
419         return *pos ? dev_get_idx(*pos) : (void *) 1;
420 }
421
422 void atm_dev_seq_stop(struct seq_file *seq, void *v)
423 {
424         spin_unlock(&atm_dev_lock);
425 }
426  
427 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
428 {
429         ++*pos;
430         v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
431         return (v == &atm_devs) ? NULL : v;
432 }
433
434
435 EXPORT_SYMBOL(atm_dev_register);
436 EXPORT_SYMBOL(atm_dev_deregister);
437 EXPORT_SYMBOL(atm_dev_lookup);
438 EXPORT_SYMBOL(shutdown_atm_dev);