xref: /openbmc/linux/net/atm/resources.c (revision 22fd411a) 
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 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
11 
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 #include <linux/slab.h>
23 
24 #include <net/sock.h>	 /* for struct sock */
25 
26 #include "common.h"
27 #include "resources.h"
28 #include "addr.h"
29 
30 
31 LIST_HEAD(atm_devs);
32 DEFINE_MUTEX(atm_dev_mutex);
33 
34 static struct atm_dev *__alloc_atm_dev(const char *type)
35 {
36 	struct atm_dev *dev;
37 
38 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
39 	if (!dev)
40 		return NULL;
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 EXPORT_SYMBOL(atm_dev_lookup);
76 
77 struct atm_dev *atm_dev_register(const char *type, struct device *parent,
78 				 const struct atmdev_ops *ops, int number,
79 				 unsigned long *flags)
80 {
81 	struct atm_dev *dev, *inuse;
82 
83 	dev = __alloc_atm_dev(type);
84 	if (!dev) {
85 		pr_err("no space for dev %s\n", type);
86 		return NULL;
87 	}
88 	mutex_lock(&atm_dev_mutex);
89 	if (number != -1) {
90 		inuse = __atm_dev_lookup(number);
91 		if (inuse) {
92 			atm_dev_put(inuse);
93 			mutex_unlock(&atm_dev_mutex);
94 			kfree(dev);
95 			return NULL;
96 		}
97 		dev->number = number;
98 	} else {
99 		dev->number = 0;
100 		while ((inuse = __atm_dev_lookup(dev->number))) {
101 			atm_dev_put(inuse);
102 			dev->number++;
103 		}
104 	}
105 
106 	dev->ops = ops;
107 	if (flags)
108 		dev->flags = *flags;
109 	else
110 		memset(&dev->flags, 0, sizeof(dev->flags));
111 	memset(&dev->stats, 0, sizeof(dev->stats));
112 	atomic_set(&dev->refcnt, 1);
113 
114 	if (atm_proc_dev_register(dev) < 0) {
115 		pr_err("atm_proc_dev_register failed for dev %s\n", type);
116 		goto out_fail;
117 	}
118 
119 	if (atm_register_sysfs(dev, parent) < 0) {
120 		pr_err("atm_register_sysfs failed for dev %s\n", type);
121 		atm_proc_dev_deregister(dev);
122 		goto out_fail;
123 	}
124 
125 	list_add_tail(&dev->dev_list, &atm_devs);
126 
127 out:
128 	mutex_unlock(&atm_dev_mutex);
129 	return dev;
130 
131 out_fail:
132 	kfree(dev);
133 	dev = NULL;
134 	goto out;
135 }
136 EXPORT_SYMBOL(atm_dev_register);
137 
138 void atm_dev_deregister(struct atm_dev *dev)
139 {
140 	BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
141 	set_bit(ATM_DF_REMOVED, &dev->flags);
142 
143 	/*
144 	 * if we remove current device from atm_devs list, new device
145 	 * with same number can appear, such we need deregister proc,
146 	 * release async all vccs and remove them from vccs list too
147 	 */
148 	mutex_lock(&atm_dev_mutex);
149 	list_del(&dev->dev_list);
150 	mutex_unlock(&atm_dev_mutex);
151 
152 	atm_dev_release_vccs(dev);
153 	atm_unregister_sysfs(dev);
154 	atm_proc_dev_deregister(dev);
155 
156 	atm_dev_put(dev);
157 }
158 EXPORT_SYMBOL(atm_dev_deregister);
159 
160 static void copy_aal_stats(struct k_atm_aal_stats *from,
161     struct atm_aal_stats *to)
162 {
163 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
164 	__AAL_STAT_ITEMS
165 #undef __HANDLE_ITEM
166 }
167 
168 static void subtract_aal_stats(struct k_atm_aal_stats *from,
169     struct atm_aal_stats *to)
170 {
171 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
172 	__AAL_STAT_ITEMS
173 #undef __HANDLE_ITEM
174 }
175 
176 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg,
177 		       int zero)
178 {
179 	struct atm_dev_stats tmp;
180 	int error = 0;
181 
182 	copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
183 	copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
184 	copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
185 	if (arg)
186 		error = copy_to_user(arg, &tmp, sizeof(tmp));
187 	if (zero && !error) {
188 		subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
189 		subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
190 		subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
191 	}
192 	return error ? -EFAULT : 0;
193 }
194 
195 int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat)
196 {
197 	void __user *buf;
198 	int error, len, number, size = 0;
199 	struct atm_dev *dev;
200 	struct list_head *p;
201 	int *tmp_buf, *tmp_p;
202 	int __user *sioc_len;
203 	int __user *iobuf_len;
204 
205 #ifndef CONFIG_COMPAT
206 	compat = 0; /* Just so the compiler _knows_ */
207 #endif
208 
209 	switch (cmd) {
210 	case ATM_GETNAMES:
211 		if (compat) {
212 #ifdef CONFIG_COMPAT
213 			struct compat_atm_iobuf __user *ciobuf = arg;
214 			compat_uptr_t cbuf;
215 			iobuf_len = &ciobuf->length;
216 			if (get_user(cbuf, &ciobuf->buffer))
217 				return -EFAULT;
218 			buf = compat_ptr(cbuf);
219 #endif
220 		} else {
221 			struct atm_iobuf __user *iobuf = arg;
222 			iobuf_len = &iobuf->length;
223 			if (get_user(buf, &iobuf->buffer))
224 				return -EFAULT;
225 		}
226 		if (get_user(len, iobuf_len))
227 			return -EFAULT;
228 		mutex_lock(&atm_dev_mutex);
229 		list_for_each(p, &atm_devs)
230 			size += sizeof(int);
231 		if (size > len) {
232 			mutex_unlock(&atm_dev_mutex);
233 			return -E2BIG;
234 		}
235 		tmp_buf = kmalloc(size, GFP_ATOMIC);
236 		if (!tmp_buf) {
237 			mutex_unlock(&atm_dev_mutex);
238 			return -ENOMEM;
239 		}
240 		tmp_p = tmp_buf;
241 		list_for_each(p, &atm_devs) {
242 			dev = list_entry(p, struct atm_dev, dev_list);
243 			*tmp_p++ = dev->number;
244 		}
245 		mutex_unlock(&atm_dev_mutex);
246 		error = ((copy_to_user(buf, tmp_buf, size)) ||
247 			 put_user(size, iobuf_len))
248 			? -EFAULT : 0;
249 		kfree(tmp_buf);
250 		return error;
251 	default:
252 		break;
253 	}
254 
255 	if (compat) {
256 #ifdef CONFIG_COMPAT
257 		struct compat_atmif_sioc __user *csioc = arg;
258 		compat_uptr_t carg;
259 
260 		sioc_len = &csioc->length;
261 		if (get_user(carg, &csioc->arg))
262 			return -EFAULT;
263 		buf = compat_ptr(carg);
264 
265 		if (get_user(len, &csioc->length))
266 			return -EFAULT;
267 		if (get_user(number, &csioc->number))
268 			return -EFAULT;
269 #endif
270 	} else {
271 		struct atmif_sioc __user *sioc = arg;
272 
273 		sioc_len = &sioc->length;
274 		if (get_user(buf, &sioc->arg))
275 			return -EFAULT;
276 		if (get_user(len, &sioc->length))
277 			return -EFAULT;
278 		if (get_user(number, &sioc->number))
279 			return -EFAULT;
280 	}
281 
282 	dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
283 				      number);
284 	if (!dev)
285 		return -ENODEV;
286 
287 	switch (cmd) {
288 	case ATM_GETTYPE:
289 		size = strlen(dev->type) + 1;
290 		if (copy_to_user(buf, dev->type, size)) {
291 			error = -EFAULT;
292 			goto done;
293 		}
294 		break;
295 	case ATM_GETESI:
296 		size = ESI_LEN;
297 		if (copy_to_user(buf, dev->esi, size)) {
298 			error = -EFAULT;
299 			goto done;
300 		}
301 		break;
302 	case ATM_SETESI:
303 	{
304 		int i;
305 
306 		for (i = 0; i < ESI_LEN; i++)
307 			if (dev->esi[i]) {
308 				error = -EEXIST;
309 				goto done;
310 			}
311 	}
312 	/* fall through */
313 	case ATM_SETESIF:
314 	{
315 		unsigned char esi[ESI_LEN];
316 
317 		if (!capable(CAP_NET_ADMIN)) {
318 			error = -EPERM;
319 			goto done;
320 		}
321 		if (copy_from_user(esi, buf, ESI_LEN)) {
322 			error = -EFAULT;
323 			goto done;
324 		}
325 		memcpy(dev->esi, esi, ESI_LEN);
326 		error =  ESI_LEN;
327 		goto done;
328 	}
329 	case ATM_GETSTATZ:
330 		if (!capable(CAP_NET_ADMIN)) {
331 			error = -EPERM;
332 			goto done;
333 		}
334 		/* fall through */
335 	case ATM_GETSTAT:
336 		size = sizeof(struct atm_dev_stats);
337 		error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
338 		if (error)
339 			goto done;
340 		break;
341 	case ATM_GETCIRANGE:
342 		size = sizeof(struct atm_cirange);
343 		if (copy_to_user(buf, &dev->ci_range, size)) {
344 			error = -EFAULT;
345 			goto done;
346 		}
347 		break;
348 	case ATM_GETLINKRATE:
349 		size = sizeof(int);
350 		if (copy_to_user(buf, &dev->link_rate, size)) {
351 			error = -EFAULT;
352 			goto done;
353 		}
354 		break;
355 	case ATM_RSTADDR:
356 		if (!capable(CAP_NET_ADMIN)) {
357 			error = -EPERM;
358 			goto done;
359 		}
360 		atm_reset_addr(dev, ATM_ADDR_LOCAL);
361 		break;
362 	case ATM_ADDADDR:
363 	case ATM_DELADDR:
364 	case ATM_ADDLECSADDR:
365 	case ATM_DELLECSADDR:
366 	{
367 		struct sockaddr_atmsvc addr;
368 
369 		if (!capable(CAP_NET_ADMIN)) {
370 			error = -EPERM;
371 			goto done;
372 		}
373 
374 		if (copy_from_user(&addr, buf, sizeof(addr))) {
375 			error = -EFAULT;
376 			goto done;
377 		}
378 		if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
379 			error = atm_add_addr(dev, &addr,
380 					     (cmd == ATM_ADDADDR ?
381 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
382 		else
383 			error = atm_del_addr(dev, &addr,
384 					     (cmd == ATM_DELADDR ?
385 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
386 		goto done;
387 	}
388 	case ATM_GETADDR:
389 	case ATM_GETLECSADDR:
390 		error = atm_get_addr(dev, buf, len,
391 				     (cmd == ATM_GETADDR ?
392 				      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
393 		if (error < 0)
394 			goto done;
395 		size = error;
396 		/* may return 0, but later on size == 0 means "don't
397 		   write the length" */
398 		error = put_user(size, sioc_len) ? -EFAULT : 0;
399 		goto done;
400 	case ATM_SETLOOP:
401 		if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
402 		    __ATM_LM_XTLOC((int) (unsigned long) buf) >
403 		    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
404 			error = -EINVAL;
405 			goto done;
406 		}
407 		/* fall through */
408 	case ATM_SETCIRANGE:
409 	case SONET_GETSTATZ:
410 	case SONET_SETDIAG:
411 	case SONET_CLRDIAG:
412 	case SONET_SETFRAMING:
413 		if (!capable(CAP_NET_ADMIN)) {
414 			error = -EPERM;
415 			goto done;
416 		}
417 		/* fall through */
418 	default:
419 		if (compat) {
420 #ifdef CONFIG_COMPAT
421 			if (!dev->ops->compat_ioctl) {
422 				error = -EINVAL;
423 				goto done;
424 			}
425 			size = dev->ops->compat_ioctl(dev, cmd, buf);
426 #endif
427 		} else {
428 			if (!dev->ops->ioctl) {
429 				error = -EINVAL;
430 				goto done;
431 			}
432 			size = dev->ops->ioctl(dev, cmd, buf);
433 		}
434 		if (size < 0) {
435 			error = (size == -ENOIOCTLCMD ? -EINVAL : size);
436 			goto done;
437 		}
438 	}
439 
440 	if (size)
441 		error = put_user(size, sioc_len) ? -EFAULT : 0;
442 	else
443 		error = 0;
444 done:
445 	atm_dev_put(dev);
446 	return error;
447 }
448 
449 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
450 {
451 	mutex_lock(&atm_dev_mutex);
452 	return seq_list_start_head(&atm_devs, *pos);
453 }
454 
455 void atm_dev_seq_stop(struct seq_file *seq, void *v)
456 {
457 	mutex_unlock(&atm_dev_mutex);
458 }
459 
460 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
461 {
462 	return seq_list_next(v, &atm_devs, pos);
463 }
464