xref: /linux/net/atm/resources.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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 		mutex_unlock(&atm_dev_mutex);
118 		kfree(dev);
119 		return NULL;
120 	}
121 	list_add_tail(&dev->dev_list, &atm_devs);
122 	mutex_unlock(&atm_dev_mutex);
123 
124 	return dev;
125 }
126 
127 
128 void atm_dev_deregister(struct atm_dev *dev)
129 {
130 	BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
131 	set_bit(ATM_DF_REMOVED, &dev->flags);
132 
133 	/*
134 	 * if we remove current device from atm_devs list, new device
135 	 * with same number can appear, such we need deregister proc,
136 	 * release async all vccs and remove them from vccs list too
137 	 */
138 	mutex_lock(&atm_dev_mutex);
139 	list_del(&dev->dev_list);
140 	mutex_unlock(&atm_dev_mutex);
141 
142 	atm_dev_release_vccs(dev);
143 	atm_proc_dev_deregister(dev);
144 
145 	atm_dev_put(dev);
146 }
147 
148 
149 static void copy_aal_stats(struct k_atm_aal_stats *from,
150     struct atm_aal_stats *to)
151 {
152 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
153 	__AAL_STAT_ITEMS
154 #undef __HANDLE_ITEM
155 }
156 
157 
158 static void subtract_aal_stats(struct k_atm_aal_stats *from,
159     struct atm_aal_stats *to)
160 {
161 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
162 	__AAL_STAT_ITEMS
163 #undef __HANDLE_ITEM
164 }
165 
166 
167 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
168 {
169 	struct atm_dev_stats tmp;
170 	int error = 0;
171 
172 	copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
173 	copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
174 	copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
175 	if (arg)
176 		error = copy_to_user(arg, &tmp, sizeof(tmp));
177 	if (zero && !error) {
178 		subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
179 		subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
180 		subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
181 	}
182 	return error ? -EFAULT : 0;
183 }
184 
185 
186 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
187 {
188 	void __user *buf;
189 	int error, len, number, size = 0;
190 	struct atm_dev *dev;
191 	struct list_head *p;
192 	int *tmp_buf, *tmp_p;
193 	struct atm_iobuf __user *iobuf = arg;
194 	struct atmif_sioc __user *sioc = arg;
195 	switch (cmd) {
196 		case ATM_GETNAMES:
197 			if (get_user(buf, &iobuf->buffer))
198 				return -EFAULT;
199 			if (get_user(len, &iobuf->length))
200 				return -EFAULT;
201 			mutex_lock(&atm_dev_mutex);
202 			list_for_each(p, &atm_devs)
203 				size += sizeof(int);
204 			if (size > len) {
205 				mutex_unlock(&atm_dev_mutex);
206 				return -E2BIG;
207 			}
208 			tmp_buf = kmalloc(size, GFP_ATOMIC);
209 			if (!tmp_buf) {
210 				mutex_unlock(&atm_dev_mutex);
211 				return -ENOMEM;
212 			}
213 			tmp_p = tmp_buf;
214 			list_for_each(p, &atm_devs) {
215 				dev = list_entry(p, struct atm_dev, dev_list);
216 				*tmp_p++ = dev->number;
217 			}
218 			mutex_unlock(&atm_dev_mutex);
219 		        error = ((copy_to_user(buf, tmp_buf, size)) ||
220 					put_user(size, &iobuf->length))
221 						? -EFAULT : 0;
222 			kfree(tmp_buf);
223 			return error;
224 		default:
225 			break;
226 	}
227 
228 	if (get_user(buf, &sioc->arg))
229 		return -EFAULT;
230 	if (get_user(len, &sioc->length))
231 		return -EFAULT;
232 	if (get_user(number, &sioc->number))
233 		return -EFAULT;
234 
235 	if (!(dev = try_then_request_module(atm_dev_lookup(number),
236 					    "atm-device-%d", number)))
237 		return -ENODEV;
238 
239 	switch (cmd) {
240 		case ATM_GETTYPE:
241 			size = strlen(dev->type) + 1;
242 			if (copy_to_user(buf, dev->type, size)) {
243 				error = -EFAULT;
244 				goto done;
245 			}
246 			break;
247 		case ATM_GETESI:
248 			size = ESI_LEN;
249 			if (copy_to_user(buf, dev->esi, size)) {
250 				error = -EFAULT;
251 				goto done;
252 			}
253 			break;
254 		case ATM_SETESI:
255 			{
256 				int i;
257 
258 				for (i = 0; i < ESI_LEN; i++)
259 					if (dev->esi[i]) {
260 						error = -EEXIST;
261 						goto done;
262 					}
263 			}
264 			/* fall through */
265 		case ATM_SETESIF:
266 			{
267 				unsigned char esi[ESI_LEN];
268 
269 				if (!capable(CAP_NET_ADMIN)) {
270 					error = -EPERM;
271 					goto done;
272 				}
273 				if (copy_from_user(esi, buf, ESI_LEN)) {
274 					error = -EFAULT;
275 					goto done;
276 				}
277 				memcpy(dev->esi, esi, ESI_LEN);
278 				error =  ESI_LEN;
279 				goto done;
280 			}
281 		case ATM_GETSTATZ:
282 			if (!capable(CAP_NET_ADMIN)) {
283 				error = -EPERM;
284 				goto done;
285 			}
286 			/* fall through */
287 		case ATM_GETSTAT:
288 			size = sizeof(struct atm_dev_stats);
289 			error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
290 			if (error)
291 				goto done;
292 			break;
293 		case ATM_GETCIRANGE:
294 			size = sizeof(struct atm_cirange);
295 			if (copy_to_user(buf, &dev->ci_range, size)) {
296 				error = -EFAULT;
297 				goto done;
298 			}
299 			break;
300 		case ATM_GETLINKRATE:
301 			size = sizeof(int);
302 			if (copy_to_user(buf, &dev->link_rate, size)) {
303 				error = -EFAULT;
304 				goto done;
305 			}
306 			break;
307 		case ATM_RSTADDR:
308 			if (!capable(CAP_NET_ADMIN)) {
309 				error = -EPERM;
310 				goto done;
311 			}
312 			atm_reset_addr(dev, ATM_ADDR_LOCAL);
313 			break;
314 		case ATM_ADDADDR:
315 		case ATM_DELADDR:
316 		case ATM_ADDLECSADDR:
317 		case ATM_DELLECSADDR:
318 			if (!capable(CAP_NET_ADMIN)) {
319 				error = -EPERM;
320 				goto done;
321 			}
322 			{
323 				struct sockaddr_atmsvc addr;
324 
325 				if (copy_from_user(&addr, buf, sizeof(addr))) {
326 					error = -EFAULT;
327 					goto done;
328 				}
329 				if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
330 					error = atm_add_addr(dev, &addr,
331 							     (cmd == ATM_ADDADDR ?
332 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
333 				else
334 					error = atm_del_addr(dev, &addr,
335 							     (cmd == ATM_DELADDR ?
336 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
337 				goto done;
338 			}
339 		case ATM_GETADDR:
340 		case ATM_GETLECSADDR:
341 			error = atm_get_addr(dev, buf, len,
342 					     (cmd == ATM_GETADDR ?
343 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
344 			if (error < 0)
345 				goto done;
346 			size = error;
347 			/* may return 0, but later on size == 0 means "don't
348 			   write the length" */
349 			error = put_user(size, &sioc->length)
350 				? -EFAULT : 0;
351 			goto done;
352 		case ATM_SETLOOP:
353 			if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
354 			    __ATM_LM_XTLOC((int) (unsigned long) buf) >
355 			    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
356 				error = -EINVAL;
357 				goto done;
358 			}
359 			/* fall through */
360 		case ATM_SETCIRANGE:
361 		case SONET_GETSTATZ:
362 		case SONET_SETDIAG:
363 		case SONET_CLRDIAG:
364 		case SONET_SETFRAMING:
365 			if (!capable(CAP_NET_ADMIN)) {
366 				error = -EPERM;
367 				goto done;
368 			}
369 			/* fall through */
370 		default:
371 			if (!dev->ops->ioctl) {
372 				error = -EINVAL;
373 				goto done;
374 			}
375 			size = dev->ops->ioctl(dev, cmd, buf);
376 			if (size < 0) {
377 				error = (size == -ENOIOCTLCMD ? -EINVAL : size);
378 				goto done;
379 			}
380 	}
381 
382 	if (size)
383 		error = put_user(size, &sioc->length)
384 			? -EFAULT : 0;
385 	else
386 		error = 0;
387 done:
388 	atm_dev_put(dev);
389 	return error;
390 }
391 
392 static __inline__ void *dev_get_idx(loff_t left)
393 {
394 	struct list_head *p;
395 
396 	list_for_each(p, &atm_devs) {
397 		if (!--left)
398 			break;
399 	}
400 	return (p != &atm_devs) ? p : NULL;
401 }
402 
403 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
404 {
405  	mutex_lock(&atm_dev_mutex);
406 	return *pos ? dev_get_idx(*pos) : (void *) 1;
407 }
408 
409 void atm_dev_seq_stop(struct seq_file *seq, void *v)
410 {
411  	mutex_unlock(&atm_dev_mutex);
412 }
413 
414 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
415 {
416 	++*pos;
417 	v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
418 	return (v == &atm_devs) ? NULL : v;
419 }
420 
421 
422 EXPORT_SYMBOL(atm_dev_register);
423 EXPORT_SYMBOL(atm_dev_deregister);
424 EXPORT_SYMBOL(atm_dev_lookup);
425