xref: /linux/net/atm/resources.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
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 <net/sock.h>	 /* for struct sock */
22 
23 #include "common.h"
24 #include "resources.h"
25 #include "addr.h"
26 
27 
28 LIST_HEAD(atm_devs);
29 DECLARE_MUTEX(atm_dev_mutex);
30 
31 static struct atm_dev *__alloc_atm_dev(const char *type)
32 {
33 	struct atm_dev *dev;
34 
35 	dev = kmalloc(sizeof(*dev), GFP_KERNEL);
36 	if (!dev)
37 		return NULL;
38 	memset(dev, 0, sizeof(*dev));
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 	down(&atm_dev_mutex);
69 	dev = __atm_dev_lookup(number);
70 	up(&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 	down(&atm_dev_mutex);
87 	if (number != -1) {
88 		if ((inuse = __atm_dev_lookup(number))) {
89 			atm_dev_put(inuse);
90 			up(&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 		up(&atm_dev_mutex);
116 		kfree(dev);
117 		return NULL;
118 	}
119 	list_add_tail(&dev->dev_list, &atm_devs);
120 	up(&atm_dev_mutex);
121 
122 	return dev;
123 }
124 
125 
126 void atm_dev_deregister(struct atm_dev *dev)
127 {
128 	BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
129 	set_bit(ATM_DF_REMOVED, &dev->flags);
130 
131 	/*
132 	 * if we remove current device from atm_devs list, new device
133 	 * with same number can appear, such we need deregister proc,
134 	 * release async all vccs and remove them from vccs list too
135 	 */
136 	down(&atm_dev_mutex);
137 	list_del(&dev->dev_list);
138 	up(&atm_dev_mutex);
139 
140 	atm_dev_release_vccs(dev);
141 	atm_proc_dev_deregister(dev);
142 
143 	atm_dev_put(dev);
144 }
145 
146 
147 static void copy_aal_stats(struct k_atm_aal_stats *from,
148     struct atm_aal_stats *to)
149 {
150 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
151 	__AAL_STAT_ITEMS
152 #undef __HANDLE_ITEM
153 }
154 
155 
156 static void subtract_aal_stats(struct k_atm_aal_stats *from,
157     struct atm_aal_stats *to)
158 {
159 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
160 	__AAL_STAT_ITEMS
161 #undef __HANDLE_ITEM
162 }
163 
164 
165 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
166 {
167 	struct atm_dev_stats tmp;
168 	int error = 0;
169 
170 	copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
171 	copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
172 	copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
173 	if (arg)
174 		error = copy_to_user(arg, &tmp, sizeof(tmp));
175 	if (zero && !error) {
176 		subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
177 		subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
178 		subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
179 	}
180 	return error ? -EFAULT : 0;
181 }
182 
183 
184 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
185 {
186 	void __user *buf;
187 	int error, len, number, size = 0;
188 	struct atm_dev *dev;
189 	struct list_head *p;
190 	int *tmp_buf, *tmp_p;
191 	struct atm_iobuf __user *iobuf = arg;
192 	struct atmif_sioc __user *sioc = arg;
193 	switch (cmd) {
194 		case ATM_GETNAMES:
195 			if (get_user(buf, &iobuf->buffer))
196 				return -EFAULT;
197 			if (get_user(len, &iobuf->length))
198 				return -EFAULT;
199 			down(&atm_dev_mutex);
200 			list_for_each(p, &atm_devs)
201 				size += sizeof(int);
202 			if (size > len) {
203 				up(&atm_dev_mutex);
204 				return -E2BIG;
205 			}
206 			tmp_buf = kmalloc(size, GFP_ATOMIC);
207 			if (!tmp_buf) {
208 				up(&atm_dev_mutex);
209 				return -ENOMEM;
210 			}
211 			tmp_p = tmp_buf;
212 			list_for_each(p, &atm_devs) {
213 				dev = list_entry(p, struct atm_dev, dev_list);
214 				*tmp_p++ = dev->number;
215 			}
216 			up(&atm_dev_mutex);
217 		        error = ((copy_to_user(buf, tmp_buf, size)) ||
218 					put_user(size, &iobuf->length))
219 						? -EFAULT : 0;
220 			kfree(tmp_buf);
221 			return error;
222 		default:
223 			break;
224 	}
225 
226 	if (get_user(buf, &sioc->arg))
227 		return -EFAULT;
228 	if (get_user(len, &sioc->length))
229 		return -EFAULT;
230 	if (get_user(number, &sioc->number))
231 		return -EFAULT;
232 
233 	if (!(dev = try_then_request_module(atm_dev_lookup(number),
234 					    "atm-device-%d", number)))
235 		return -ENODEV;
236 
237 	switch (cmd) {
238 		case ATM_GETTYPE:
239 			size = strlen(dev->type) + 1;
240 			if (copy_to_user(buf, dev->type, size)) {
241 				error = -EFAULT;
242 				goto done;
243 			}
244 			break;
245 		case ATM_GETESI:
246 			size = ESI_LEN;
247 			if (copy_to_user(buf, dev->esi, size)) {
248 				error = -EFAULT;
249 				goto done;
250 			}
251 			break;
252 		case ATM_SETESI:
253 			{
254 				int i;
255 
256 				for (i = 0; i < ESI_LEN; i++)
257 					if (dev->esi[i]) {
258 						error = -EEXIST;
259 						goto done;
260 					}
261 			}
262 			/* fall through */
263 		case ATM_SETESIF:
264 			{
265 				unsigned char esi[ESI_LEN];
266 
267 				if (!capable(CAP_NET_ADMIN)) {
268 					error = -EPERM;
269 					goto done;
270 				}
271 				if (copy_from_user(esi, buf, ESI_LEN)) {
272 					error = -EFAULT;
273 					goto done;
274 				}
275 				memcpy(dev->esi, esi, ESI_LEN);
276 				error =  ESI_LEN;
277 				goto done;
278 			}
279 		case ATM_GETSTATZ:
280 			if (!capable(CAP_NET_ADMIN)) {
281 				error = -EPERM;
282 				goto done;
283 			}
284 			/* fall through */
285 		case ATM_GETSTAT:
286 			size = sizeof(struct atm_dev_stats);
287 			error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
288 			if (error)
289 				goto done;
290 			break;
291 		case ATM_GETCIRANGE:
292 			size = sizeof(struct atm_cirange);
293 			if (copy_to_user(buf, &dev->ci_range, size)) {
294 				error = -EFAULT;
295 				goto done;
296 			}
297 			break;
298 		case ATM_GETLINKRATE:
299 			size = sizeof(int);
300 			if (copy_to_user(buf, &dev->link_rate, size)) {
301 				error = -EFAULT;
302 				goto done;
303 			}
304 			break;
305 		case ATM_RSTADDR:
306 			if (!capable(CAP_NET_ADMIN)) {
307 				error = -EPERM;
308 				goto done;
309 			}
310 			atm_reset_addr(dev, ATM_ADDR_LOCAL);
311 			break;
312 		case ATM_ADDADDR:
313 		case ATM_DELADDR:
314 		case ATM_ADDLECSADDR:
315 		case ATM_DELLECSADDR:
316 			if (!capable(CAP_NET_ADMIN)) {
317 				error = -EPERM;
318 				goto done;
319 			}
320 			{
321 				struct sockaddr_atmsvc addr;
322 
323 				if (copy_from_user(&addr, buf, sizeof(addr))) {
324 					error = -EFAULT;
325 					goto done;
326 				}
327 				if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
328 					error = atm_add_addr(dev, &addr,
329 							     (cmd == ATM_ADDADDR ?
330 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
331 				else
332 					error = atm_del_addr(dev, &addr,
333 							     (cmd == ATM_DELADDR ?
334 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
335 				goto done;
336 			}
337 		case ATM_GETADDR:
338 		case ATM_GETLECSADDR:
339 			error = atm_get_addr(dev, buf, len,
340 					     (cmd == ATM_GETADDR ?
341 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
342 			if (error < 0)
343 				goto done;
344 			size = error;
345 			/* may return 0, but later on size == 0 means "don't
346 			   write the length" */
347 			error = put_user(size, &sioc->length)
348 				? -EFAULT : 0;
349 			goto done;
350 		case ATM_SETLOOP:
351 			if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
352 			    __ATM_LM_XTLOC((int) (unsigned long) buf) >
353 			    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
354 				error = -EINVAL;
355 				goto done;
356 			}
357 			/* fall through */
358 		case ATM_SETCIRANGE:
359 		case SONET_GETSTATZ:
360 		case SONET_SETDIAG:
361 		case SONET_CLRDIAG:
362 		case SONET_SETFRAMING:
363 			if (!capable(CAP_NET_ADMIN)) {
364 				error = -EPERM;
365 				goto done;
366 			}
367 			/* fall through */
368 		default:
369 			if (!dev->ops->ioctl) {
370 				error = -EINVAL;
371 				goto done;
372 			}
373 			size = dev->ops->ioctl(dev, cmd, buf);
374 			if (size < 0) {
375 				error = (size == -ENOIOCTLCMD ? -EINVAL : size);
376 				goto done;
377 			}
378 	}
379 
380 	if (size)
381 		error = put_user(size, &sioc->length)
382 			? -EFAULT : 0;
383 	else
384 		error = 0;
385 done:
386 	atm_dev_put(dev);
387 	return error;
388 }
389 
390 static __inline__ void *dev_get_idx(loff_t left)
391 {
392 	struct list_head *p;
393 
394 	list_for_each(p, &atm_devs) {
395 		if (!--left)
396 			break;
397 	}
398 	return (p != &atm_devs) ? p : NULL;
399 }
400 
401 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
402 {
403  	down(&atm_dev_mutex);
404 	return *pos ? dev_get_idx(*pos) : (void *) 1;
405 }
406 
407 void atm_dev_seq_stop(struct seq_file *seq, void *v)
408 {
409  	up(&atm_dev_mutex);
410 }
411 
412 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
413 {
414 	++*pos;
415 	v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
416 	return (v == &atm_devs) ? NULL : v;
417 }
418 
419 
420 EXPORT_SYMBOL(atm_dev_register);
421 EXPORT_SYMBOL(atm_dev_deregister);
422 EXPORT_SYMBOL(atm_dev_lookup);
423