xref: /linux/net/atm/resources.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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/capability.h>
20 #include <linux/delay.h>
21 #include <linux/mutex.h>
22 
23 #include <net/sock.h>	 /* for struct sock */
24 
25 #include "common.h"
26 #include "resources.h"
27 #include "addr.h"
28 
29 
30 LIST_HEAD(atm_devs);
31 DEFINE_MUTEX(atm_dev_mutex);
32 
33 static struct atm_dev *__alloc_atm_dev(const char *type)
34 {
35 	struct atm_dev *dev;
36 
37 	dev = kmalloc(sizeof(*dev), GFP_KERNEL);
38 	if (!dev)
39 		return NULL;
40 	memset(dev, 0, sizeof(*dev));
41 	dev->type = type;
42 	dev->signal = ATM_PHY_SIG_UNKNOWN;
43 	dev->link_rate = ATM_OC3_PCR;
44 	spin_lock_init(&dev->lock);
45 	INIT_LIST_HEAD(&dev->local);
46 	INIT_LIST_HEAD(&dev->lecs);
47 
48 	return dev;
49 }
50 
51 static struct atm_dev *__atm_dev_lookup(int number)
52 {
53 	struct atm_dev *dev;
54 	struct list_head *p;
55 
56 	list_for_each(p, &atm_devs) {
57 		dev = list_entry(p, struct atm_dev, dev_list);
58 		if (dev->number == number) {
59 			atm_dev_hold(dev);
60 			return dev;
61 		}
62 	}
63 	return NULL;
64 }
65 
66 struct atm_dev *atm_dev_lookup(int number)
67 {
68 	struct atm_dev *dev;
69 
70 	mutex_lock(&atm_dev_mutex);
71 	dev = __atm_dev_lookup(number);
72 	mutex_unlock(&atm_dev_mutex);
73 	return dev;
74 }
75 
76 
77 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
78 				 int number, unsigned long *flags)
79 {
80 	struct atm_dev *dev, *inuse;
81 
82 	dev = __alloc_atm_dev(type);
83 	if (!dev) {
84 		printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
85 		    type);
86 		return NULL;
87 	}
88 	mutex_lock(&atm_dev_mutex);
89 	if (number != -1) {
90 		if ((inuse = __atm_dev_lookup(number))) {
91 			atm_dev_put(inuse);
92 			mutex_unlock(&atm_dev_mutex);
93 			kfree(dev);
94 			return NULL;
95 		}
96 		dev->number = number;
97 	} else {
98 		dev->number = 0;
99 		while ((inuse = __atm_dev_lookup(dev->number))) {
100 			atm_dev_put(inuse);
101 			dev->number++;
102 		}
103 	}
104 
105 	dev->ops = ops;
106 	if (flags)
107 		dev->flags = *flags;
108 	else
109 		memset(&dev->flags, 0, sizeof(dev->flags));
110 	memset(&dev->stats, 0, sizeof(dev->stats));
111 	atomic_set(&dev->refcnt, 1);
112 
113 	if (atm_proc_dev_register(dev) < 0) {
114 		printk(KERN_ERR "atm_dev_register: "
115 		       "atm_proc_dev_register failed for dev %s\n",
116 		       type);
117 		goto out_fail;
118 	}
119 
120 	if (atm_register_sysfs(dev) < 0) {
121 		printk(KERN_ERR "atm_dev_register: "
122 		       "atm_register_sysfs failed for dev %s\n",
123 		       type);
124 		atm_proc_dev_deregister(dev);
125 		goto out_fail;
126 	}
127 
128 	list_add_tail(&dev->dev_list, &atm_devs);
129 
130 out:
131 	mutex_unlock(&atm_dev_mutex);
132 	return dev;
133 
134 out_fail:
135 	kfree(dev);
136 	dev = NULL;
137 	goto out;
138 }
139 
140 
141 void atm_dev_deregister(struct atm_dev *dev)
142 {
143 	BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
144 	set_bit(ATM_DF_REMOVED, &dev->flags);
145 
146 	/*
147 	 * if we remove current device from atm_devs list, new device
148 	 * with same number can appear, such we need deregister proc,
149 	 * release async all vccs and remove them from vccs list too
150 	 */
151 	mutex_lock(&atm_dev_mutex);
152 	list_del(&dev->dev_list);
153 	mutex_unlock(&atm_dev_mutex);
154 
155 	atm_dev_release_vccs(dev);
156 	atm_unregister_sysfs(dev);
157 	atm_proc_dev_deregister(dev);
158 
159 	atm_dev_put(dev);
160 }
161 
162 
163 static void copy_aal_stats(struct k_atm_aal_stats *from,
164     struct atm_aal_stats *to)
165 {
166 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
167 	__AAL_STAT_ITEMS
168 #undef __HANDLE_ITEM
169 }
170 
171 
172 static void subtract_aal_stats(struct k_atm_aal_stats *from,
173     struct atm_aal_stats *to)
174 {
175 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
176 	__AAL_STAT_ITEMS
177 #undef __HANDLE_ITEM
178 }
179 
180 
181 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
182 {
183 	struct atm_dev_stats tmp;
184 	int error = 0;
185 
186 	copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
187 	copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
188 	copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
189 	if (arg)
190 		error = copy_to_user(arg, &tmp, sizeof(tmp));
191 	if (zero && !error) {
192 		subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
193 		subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
194 		subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
195 	}
196 	return error ? -EFAULT : 0;
197 }
198 
199 
200 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
201 {
202 	void __user *buf;
203 	int error, len, number, size = 0;
204 	struct atm_dev *dev;
205 	struct list_head *p;
206 	int *tmp_buf, *tmp_p;
207 	struct atm_iobuf __user *iobuf = arg;
208 	struct atmif_sioc __user *sioc = arg;
209 	switch (cmd) {
210 		case ATM_GETNAMES:
211 			if (get_user(buf, &iobuf->buffer))
212 				return -EFAULT;
213 			if (get_user(len, &iobuf->length))
214 				return -EFAULT;
215 			mutex_lock(&atm_dev_mutex);
216 			list_for_each(p, &atm_devs)
217 				size += sizeof(int);
218 			if (size > len) {
219 				mutex_unlock(&atm_dev_mutex);
220 				return -E2BIG;
221 			}
222 			tmp_buf = kmalloc(size, GFP_ATOMIC);
223 			if (!tmp_buf) {
224 				mutex_unlock(&atm_dev_mutex);
225 				return -ENOMEM;
226 			}
227 			tmp_p = tmp_buf;
228 			list_for_each(p, &atm_devs) {
229 				dev = list_entry(p, struct atm_dev, dev_list);
230 				*tmp_p++ = dev->number;
231 			}
232 			mutex_unlock(&atm_dev_mutex);
233 		        error = ((copy_to_user(buf, tmp_buf, size)) ||
234 					put_user(size, &iobuf->length))
235 						? -EFAULT : 0;
236 			kfree(tmp_buf);
237 			return error;
238 		default:
239 			break;
240 	}
241 
242 	if (get_user(buf, &sioc->arg))
243 		return -EFAULT;
244 	if (get_user(len, &sioc->length))
245 		return -EFAULT;
246 	if (get_user(number, &sioc->number))
247 		return -EFAULT;
248 
249 	if (!(dev = try_then_request_module(atm_dev_lookup(number),
250 					    "atm-device-%d", number)))
251 		return -ENODEV;
252 
253 	switch (cmd) {
254 		case ATM_GETTYPE:
255 			size = strlen(dev->type) + 1;
256 			if (copy_to_user(buf, dev->type, size)) {
257 				error = -EFAULT;
258 				goto done;
259 			}
260 			break;
261 		case ATM_GETESI:
262 			size = ESI_LEN;
263 			if (copy_to_user(buf, dev->esi, size)) {
264 				error = -EFAULT;
265 				goto done;
266 			}
267 			break;
268 		case ATM_SETESI:
269 			{
270 				int i;
271 
272 				for (i = 0; i < ESI_LEN; i++)
273 					if (dev->esi[i]) {
274 						error = -EEXIST;
275 						goto done;
276 					}
277 			}
278 			/* fall through */
279 		case ATM_SETESIF:
280 			{
281 				unsigned char esi[ESI_LEN];
282 
283 				if (!capable(CAP_NET_ADMIN)) {
284 					error = -EPERM;
285 					goto done;
286 				}
287 				if (copy_from_user(esi, buf, ESI_LEN)) {
288 					error = -EFAULT;
289 					goto done;
290 				}
291 				memcpy(dev->esi, esi, ESI_LEN);
292 				error =  ESI_LEN;
293 				goto done;
294 			}
295 		case ATM_GETSTATZ:
296 			if (!capable(CAP_NET_ADMIN)) {
297 				error = -EPERM;
298 				goto done;
299 			}
300 			/* fall through */
301 		case ATM_GETSTAT:
302 			size = sizeof(struct atm_dev_stats);
303 			error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
304 			if (error)
305 				goto done;
306 			break;
307 		case ATM_GETCIRANGE:
308 			size = sizeof(struct atm_cirange);
309 			if (copy_to_user(buf, &dev->ci_range, size)) {
310 				error = -EFAULT;
311 				goto done;
312 			}
313 			break;
314 		case ATM_GETLINKRATE:
315 			size = sizeof(int);
316 			if (copy_to_user(buf, &dev->link_rate, size)) {
317 				error = -EFAULT;
318 				goto done;
319 			}
320 			break;
321 		case ATM_RSTADDR:
322 			if (!capable(CAP_NET_ADMIN)) {
323 				error = -EPERM;
324 				goto done;
325 			}
326 			atm_reset_addr(dev, ATM_ADDR_LOCAL);
327 			break;
328 		case ATM_ADDADDR:
329 		case ATM_DELADDR:
330 		case ATM_ADDLECSADDR:
331 		case ATM_DELLECSADDR:
332 			if (!capable(CAP_NET_ADMIN)) {
333 				error = -EPERM;
334 				goto done;
335 			}
336 			{
337 				struct sockaddr_atmsvc addr;
338 
339 				if (copy_from_user(&addr, buf, sizeof(addr))) {
340 					error = -EFAULT;
341 					goto done;
342 				}
343 				if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
344 					error = atm_add_addr(dev, &addr,
345 							     (cmd == ATM_ADDADDR ?
346 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
347 				else
348 					error = atm_del_addr(dev, &addr,
349 							     (cmd == ATM_DELADDR ?
350 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
351 				goto done;
352 			}
353 		case ATM_GETADDR:
354 		case ATM_GETLECSADDR:
355 			error = atm_get_addr(dev, buf, len,
356 					     (cmd == ATM_GETADDR ?
357 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
358 			if (error < 0)
359 				goto done;
360 			size = error;
361 			/* may return 0, but later on size == 0 means "don't
362 			   write the length" */
363 			error = put_user(size, &sioc->length)
364 				? -EFAULT : 0;
365 			goto done;
366 		case ATM_SETLOOP:
367 			if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
368 			    __ATM_LM_XTLOC((int) (unsigned long) buf) >
369 			    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
370 				error = -EINVAL;
371 				goto done;
372 			}
373 			/* fall through */
374 		case ATM_SETCIRANGE:
375 		case SONET_GETSTATZ:
376 		case SONET_SETDIAG:
377 		case SONET_CLRDIAG:
378 		case SONET_SETFRAMING:
379 			if (!capable(CAP_NET_ADMIN)) {
380 				error = -EPERM;
381 				goto done;
382 			}
383 			/* fall through */
384 		default:
385 			if (!dev->ops->ioctl) {
386 				error = -EINVAL;
387 				goto done;
388 			}
389 			size = dev->ops->ioctl(dev, cmd, buf);
390 			if (size < 0) {
391 				error = (size == -ENOIOCTLCMD ? -EINVAL : size);
392 				goto done;
393 			}
394 	}
395 
396 	if (size)
397 		error = put_user(size, &sioc->length)
398 			? -EFAULT : 0;
399 	else
400 		error = 0;
401 done:
402 	atm_dev_put(dev);
403 	return error;
404 }
405 
406 static __inline__ void *dev_get_idx(loff_t left)
407 {
408 	struct list_head *p;
409 
410 	list_for_each(p, &atm_devs) {
411 		if (!--left)
412 			break;
413 	}
414 	return (p != &atm_devs) ? p : NULL;
415 }
416 
417 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
418 {
419  	mutex_lock(&atm_dev_mutex);
420 	return *pos ? dev_get_idx(*pos) : (void *) 1;
421 }
422 
423 void atm_dev_seq_stop(struct seq_file *seq, void *v)
424 {
425  	mutex_unlock(&atm_dev_mutex);
426 }
427 
428 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
429 {
430 	++*pos;
431 	v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
432 	return (v == &atm_devs) ? NULL : v;
433 }
434 
435 
436 EXPORT_SYMBOL(atm_dev_register);
437 EXPORT_SYMBOL(atm_dev_deregister);
438 EXPORT_SYMBOL(atm_dev_lookup);
439