xref: /linux/net/atm/resources.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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 = kmalloc(sizeof(*dev), GFP_KERNEL);
37 	if (!dev)
38 		return NULL;
39 	memset(dev, 0, sizeof(*dev));
40 	dev->type = type;
41 	dev->signal = ATM_PHY_SIG_UNKNOWN;
42 	dev->link_rate = ATM_OC3_PCR;
43 	spin_lock_init(&dev->lock);
44 	INIT_LIST_HEAD(&dev->local);
45 	INIT_LIST_HEAD(&dev->lecs);
46 
47 	return dev;
48 }
49 
50 static struct atm_dev *__atm_dev_lookup(int number)
51 {
52 	struct atm_dev *dev;
53 	struct list_head *p;
54 
55 	list_for_each(p, &atm_devs) {
56 		dev = list_entry(p, struct atm_dev, dev_list);
57 		if (dev->number == number) {
58 			atm_dev_hold(dev);
59 			return dev;
60 		}
61 	}
62 	return NULL;
63 }
64 
65 struct atm_dev *atm_dev_lookup(int number)
66 {
67 	struct atm_dev *dev;
68 
69 	mutex_lock(&atm_dev_mutex);
70 	dev = __atm_dev_lookup(number);
71 	mutex_unlock(&atm_dev_mutex);
72 	return dev;
73 }
74 
75 
76 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
77 				 int number, unsigned long *flags)
78 {
79 	struct atm_dev *dev, *inuse;
80 
81 	dev = __alloc_atm_dev(type);
82 	if (!dev) {
83 		printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
84 		    type);
85 		return NULL;
86 	}
87 	mutex_lock(&atm_dev_mutex);
88 	if (number != -1) {
89 		if ((inuse = __atm_dev_lookup(number))) {
90 			atm_dev_put(inuse);
91 			mutex_unlock(&atm_dev_mutex);
92 			kfree(dev);
93 			return NULL;
94 		}
95 		dev->number = number;
96 	} else {
97 		dev->number = 0;
98 		while ((inuse = __atm_dev_lookup(dev->number))) {
99 			atm_dev_put(inuse);
100 			dev->number++;
101 		}
102 	}
103 
104 	dev->ops = ops;
105 	if (flags)
106 		dev->flags = *flags;
107 	else
108 		memset(&dev->flags, 0, sizeof(dev->flags));
109 	memset(&dev->stats, 0, sizeof(dev->stats));
110 	atomic_set(&dev->refcnt, 1);
111 
112 	if (atm_proc_dev_register(dev) < 0) {
113 		printk(KERN_ERR "atm_dev_register: "
114 		       "atm_proc_dev_register failed for dev %s\n",
115 		       type);
116 		goto out_fail;
117 	}
118 
119 	if (atm_register_sysfs(dev) < 0) {
120 		printk(KERN_ERR "atm_dev_register: "
121 		       "atm_register_sysfs failed for dev %s\n",
122 		       type);
123 		atm_proc_dev_deregister(dev);
124 		goto out_fail;
125 	}
126 
127 	list_add_tail(&dev->dev_list, &atm_devs);
128 
129 out:
130 	mutex_unlock(&atm_dev_mutex);
131 	return dev;
132 
133 out_fail:
134 	kfree(dev);
135 	dev = NULL;
136 	goto out;
137 }
138 
139 
140 void atm_dev_deregister(struct atm_dev *dev)
141 {
142 	BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
143 	set_bit(ATM_DF_REMOVED, &dev->flags);
144 
145 	/*
146 	 * if we remove current device from atm_devs list, new device
147 	 * with same number can appear, such we need deregister proc,
148 	 * release async all vccs and remove them from vccs list too
149 	 */
150 	mutex_lock(&atm_dev_mutex);
151 	list_del(&dev->dev_list);
152 	mutex_unlock(&atm_dev_mutex);
153 
154 	atm_dev_release_vccs(dev);
155 	atm_unregister_sysfs(dev);
156 	atm_proc_dev_deregister(dev);
157 
158 	atm_dev_put(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 			mutex_lock(&atm_dev_mutex);
215 			list_for_each(p, &atm_devs)
216 				size += sizeof(int);
217 			if (size > len) {
218 				mutex_unlock(&atm_dev_mutex);
219 				return -E2BIG;
220 			}
221 			tmp_buf = kmalloc(size, GFP_ATOMIC);
222 			if (!tmp_buf) {
223 				mutex_unlock(&atm_dev_mutex);
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 			mutex_unlock(&atm_dev_mutex);
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  	mutex_lock(&atm_dev_mutex);
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  	mutex_unlock(&atm_dev_mutex);
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