xref: /linux/net/atm/resources.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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) : SEQ_START_TOKEN;
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 == SEQ_START_TOKEN)
430 		? 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