xref: /openbmc/linux/net/atm/resources.c (revision b6dcefde) 
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, int compat)
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 	int __user *sioc_len;
206 	int __user *iobuf_len;
207 
208 #ifndef CONFIG_COMPAT
209 	compat = 0; /* Just so the compiler _knows_ */
210 #endif
211 
212 	switch (cmd) {
213 		case ATM_GETNAMES:
214 
215 			if (compat) {
216 #ifdef CONFIG_COMPAT
217 				struct compat_atm_iobuf __user *ciobuf = arg;
218 				compat_uptr_t cbuf;
219 				iobuf_len = &ciobuf->length;
220 				if (get_user(cbuf, &ciobuf->buffer))
221 					return -EFAULT;
222 				buf = compat_ptr(cbuf);
223 #endif
224 			} else {
225 				struct atm_iobuf __user *iobuf = arg;
226 				iobuf_len = &iobuf->length;
227 				if (get_user(buf, &iobuf->buffer))
228 					return -EFAULT;
229 			}
230 			if (get_user(len, iobuf_len))
231 				return -EFAULT;
232 			mutex_lock(&atm_dev_mutex);
233 			list_for_each(p, &atm_devs)
234 				size += sizeof(int);
235 			if (size > len) {
236 				mutex_unlock(&atm_dev_mutex);
237 				return -E2BIG;
238 			}
239 			tmp_buf = kmalloc(size, GFP_ATOMIC);
240 			if (!tmp_buf) {
241 				mutex_unlock(&atm_dev_mutex);
242 				return -ENOMEM;
243 			}
244 			tmp_p = tmp_buf;
245 			list_for_each(p, &atm_devs) {
246 				dev = list_entry(p, struct atm_dev, dev_list);
247 				*tmp_p++ = dev->number;
248 			}
249 			mutex_unlock(&atm_dev_mutex);
250 			error = ((copy_to_user(buf, tmp_buf, size)) ||
251 					put_user(size, iobuf_len))
252 						? -EFAULT : 0;
253 			kfree(tmp_buf);
254 			return error;
255 		default:
256 			break;
257 	}
258 
259 	if (compat) {
260 #ifdef CONFIG_COMPAT
261 		struct compat_atmif_sioc __user *csioc = arg;
262 		compat_uptr_t carg;
263 
264 		sioc_len = &csioc->length;
265 		if (get_user(carg, &csioc->arg))
266 			return -EFAULT;
267 		buf = compat_ptr(carg);
268 
269 		if (get_user(len, &csioc->length))
270 			return -EFAULT;
271 		if (get_user(number, &csioc->number))
272 			return -EFAULT;
273 #endif
274 	} else {
275 		struct atmif_sioc __user *sioc = arg;
276 
277 		sioc_len = &sioc->length;
278 		if (get_user(buf, &sioc->arg))
279 			return -EFAULT;
280 		if (get_user(len, &sioc->length))
281 			return -EFAULT;
282 		if (get_user(number, &sioc->number))
283 			return -EFAULT;
284 	}
285 	if (!(dev = try_then_request_module(atm_dev_lookup(number),
286 					    "atm-device-%d", number)))
287 		return -ENODEV;
288 
289 	switch (cmd) {
290 		case ATM_GETTYPE:
291 			size = strlen(dev->type) + 1;
292 			if (copy_to_user(buf, dev->type, size)) {
293 				error = -EFAULT;
294 				goto done;
295 			}
296 			break;
297 		case ATM_GETESI:
298 			size = ESI_LEN;
299 			if (copy_to_user(buf, dev->esi, size)) {
300 				error = -EFAULT;
301 				goto done;
302 			}
303 			break;
304 		case ATM_SETESI:
305 			{
306 				int i;
307 
308 				for (i = 0; i < ESI_LEN; i++)
309 					if (dev->esi[i]) {
310 						error = -EEXIST;
311 						goto done;
312 					}
313 			}
314 			/* fall through */
315 		case ATM_SETESIF:
316 			{
317 				unsigned char esi[ESI_LEN];
318 
319 				if (!capable(CAP_NET_ADMIN)) {
320 					error = -EPERM;
321 					goto done;
322 				}
323 				if (copy_from_user(esi, buf, ESI_LEN)) {
324 					error = -EFAULT;
325 					goto done;
326 				}
327 				memcpy(dev->esi, esi, ESI_LEN);
328 				error =  ESI_LEN;
329 				goto done;
330 			}
331 		case ATM_GETSTATZ:
332 			if (!capable(CAP_NET_ADMIN)) {
333 				error = -EPERM;
334 				goto done;
335 			}
336 			/* fall through */
337 		case ATM_GETSTAT:
338 			size = sizeof(struct atm_dev_stats);
339 			error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
340 			if (error)
341 				goto done;
342 			break;
343 		case ATM_GETCIRANGE:
344 			size = sizeof(struct atm_cirange);
345 			if (copy_to_user(buf, &dev->ci_range, size)) {
346 				error = -EFAULT;
347 				goto done;
348 			}
349 			break;
350 		case ATM_GETLINKRATE:
351 			size = sizeof(int);
352 			if (copy_to_user(buf, &dev->link_rate, size)) {
353 				error = -EFAULT;
354 				goto done;
355 			}
356 			break;
357 		case ATM_RSTADDR:
358 			if (!capable(CAP_NET_ADMIN)) {
359 				error = -EPERM;
360 				goto done;
361 			}
362 			atm_reset_addr(dev, ATM_ADDR_LOCAL);
363 			break;
364 		case ATM_ADDADDR:
365 		case ATM_DELADDR:
366 		case ATM_ADDLECSADDR:
367 		case ATM_DELLECSADDR:
368 			if (!capable(CAP_NET_ADMIN)) {
369 				error = -EPERM;
370 				goto done;
371 			}
372 			{
373 				struct sockaddr_atmsvc addr;
374 
375 				if (copy_from_user(&addr, buf, sizeof(addr))) {
376 					error = -EFAULT;
377 					goto done;
378 				}
379 				if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
380 					error = atm_add_addr(dev, &addr,
381 							     (cmd == ATM_ADDADDR ?
382 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
383 				else
384 					error = atm_del_addr(dev, &addr,
385 							     (cmd == ATM_DELADDR ?
386 							      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
387 				goto done;
388 			}
389 		case ATM_GETADDR:
390 		case ATM_GETLECSADDR:
391 			error = atm_get_addr(dev, buf, len,
392 					     (cmd == ATM_GETADDR ?
393 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
394 			if (error < 0)
395 				goto done;
396 			size = error;
397 			/* may return 0, but later on size == 0 means "don't
398 			   write the length" */
399 			error = put_user(size, sioc_len)
400 				? -EFAULT : 0;
401 			goto done;
402 		case ATM_SETLOOP:
403 			if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
404 			    __ATM_LM_XTLOC((int) (unsigned long) buf) >
405 			    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
406 				error = -EINVAL;
407 				goto done;
408 			}
409 			/* fall through */
410 		case ATM_SETCIRANGE:
411 		case SONET_GETSTATZ:
412 		case SONET_SETDIAG:
413 		case SONET_CLRDIAG:
414 		case SONET_SETFRAMING:
415 			if (!capable(CAP_NET_ADMIN)) {
416 				error = -EPERM;
417 				goto done;
418 			}
419 			/* fall through */
420 		default:
421 			if (compat) {
422 #ifdef CONFIG_COMPAT
423 				if (!dev->ops->compat_ioctl) {
424 					error = -EINVAL;
425 					goto done;
426 				}
427 				size = dev->ops->compat_ioctl(dev, cmd, buf);
428 #endif
429 			} else {
430 				if (!dev->ops->ioctl) {
431 					error = -EINVAL;
432 					goto done;
433 				}
434 				size = dev->ops->ioctl(dev, cmd, buf);
435 			}
436 			if (size < 0) {
437 				error = (size == -ENOIOCTLCMD ? -EINVAL : size);
438 				goto done;
439 			}
440 	}
441 
442 	if (size)
443 		error = put_user(size, sioc_len)
444 			? -EFAULT : 0;
445 	else
446 		error = 0;
447 done:
448 	atm_dev_put(dev);
449 	return error;
450 }
451 
452 static __inline__ void *dev_get_idx(loff_t left)
453 {
454 	struct list_head *p;
455 
456 	list_for_each(p, &atm_devs) {
457 		if (!--left)
458 			break;
459 	}
460 	return (p != &atm_devs) ? p : NULL;
461 }
462 
463 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
464 {
465 	mutex_lock(&atm_dev_mutex);
466 	return *pos ? dev_get_idx(*pos) : SEQ_START_TOKEN;
467 }
468 
469 void atm_dev_seq_stop(struct seq_file *seq, void *v)
470 {
471 	mutex_unlock(&atm_dev_mutex);
472 }
473 
474 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
475 {
476 	++*pos;
477 	v = (v == SEQ_START_TOKEN)
478 		? atm_devs.next : ((struct list_head *)v)->next;
479 	return (v == &atm_devs) ? NULL : v;
480 }
481 
482 
483 EXPORT_SYMBOL(atm_dev_register);
484 EXPORT_SYMBOL(atm_dev_deregister);
485 EXPORT_SYMBOL(atm_dev_lookup);
486