xref: /openbmc/linux/net/atm/resources.c (revision fb1b7be9)
1 // SPDX-License-Identifier: GPL-2.0
2 /* net/atm/resources.c - Statically allocated resources */
3 
4 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
5 
6 /* Fixes
7  * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
8  * 2002/01 - don't free the whole struct sock on sk->destruct time,
9  * 	     use the default destruct function initialized by sock_init_data */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
12 
13 #include <linux/ctype.h>
14 #include <linux/string.h>
15 #include <linux/atmdev.h>
16 #include <linux/sonet.h>
17 #include <linux/kernel.h> /* for barrier */
18 #include <linux/module.h>
19 #include <linux/bitops.h>
20 #include <linux/capability.h>
21 #include <linux/delay.h>
22 #include <linux/mutex.h>
23 #include <linux/slab.h>
24 
25 #include <net/sock.h>	 /* for struct sock */
26 
27 #include "common.h"
28 #include "resources.h"
29 #include "addr.h"
30 
31 
32 LIST_HEAD(atm_devs);
33 DEFINE_MUTEX(atm_dev_mutex);
34 
__alloc_atm_dev(const char * type)35 static struct atm_dev *__alloc_atm_dev(const char *type)
36 {
37 	struct atm_dev *dev;
38 
39 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
40 	if (!dev)
41 		return NULL;
42 	dev->type = type;
43 	dev->signal = ATM_PHY_SIG_UNKNOWN;
44 	dev->link_rate = ATM_OC3_PCR;
45 	spin_lock_init(&dev->lock);
46 	INIT_LIST_HEAD(&dev->local);
47 	INIT_LIST_HEAD(&dev->lecs);
48 
49 	return dev;
50 }
51 
__atm_dev_lookup(int number)52 static struct atm_dev *__atm_dev_lookup(int number)
53 {
54 	struct atm_dev *dev;
55 
56 	list_for_each_entry(dev, &atm_devs, dev_list) {
57 		if (dev->number == number) {
58 			atm_dev_hold(dev);
59 			return dev;
60 		}
61 	}
62 	return NULL;
63 }
64 
atm_dev_lookup(int number)65 struct atm_dev *atm_dev_lookup(int number)
66 {
67 	struct atm_dev *dev;
68 
69 	mutex_lock(&atm_dev_mutex);
70 	dev = __atm_dev_lookup(number);
71 	mutex_unlock(&atm_dev_mutex);
72 	return dev;
73 }
74 EXPORT_SYMBOL(atm_dev_lookup);
75 
atm_dev_register(const char * type,struct device * parent,const struct atmdev_ops * ops,int number,unsigned long * flags)76 struct atm_dev *atm_dev_register(const char *type, struct device *parent,
77 				 const struct atmdev_ops *ops, int number,
78 				 unsigned long *flags)
79 {
80 	struct atm_dev *dev, *inuse;
81 
82 	dev = __alloc_atm_dev(type);
83 	if (!dev) {
84 		pr_err("no space for dev %s\n", type);
85 		return NULL;
86 	}
87 	mutex_lock(&atm_dev_mutex);
88 	if (number != -1) {
89 		inuse = __atm_dev_lookup(number);
90 		if (inuse) {
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 	refcount_set(&dev->refcnt, 1);
112 
113 	if (atm_proc_dev_register(dev) < 0) {
114 		pr_err("atm_proc_dev_register failed for dev %s\n", type);
115 		goto out_fail;
116 	}
117 
118 	if (atm_register_sysfs(dev, parent) < 0) {
119 		pr_err("atm_register_sysfs failed for dev %s\n", type);
120 		atm_proc_dev_deregister(dev);
121 		goto out_fail;
122 	}
123 
124 	list_add_tail(&dev->dev_list, &atm_devs);
125 
126 out:
127 	mutex_unlock(&atm_dev_mutex);
128 	return dev;
129 
130 out_fail:
131 	kfree(dev);
132 	dev = NULL;
133 	goto out;
134 }
135 EXPORT_SYMBOL(atm_dev_register);
136 
atm_dev_deregister(struct atm_dev * dev)137 void atm_dev_deregister(struct atm_dev *dev)
138 {
139 	BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
140 	set_bit(ATM_DF_REMOVED, &dev->flags);
141 
142 	/*
143 	 * if we remove current device from atm_devs list, new device
144 	 * with same number can appear, such we need deregister proc,
145 	 * release async all vccs and remove them from vccs list too
146 	 */
147 	mutex_lock(&atm_dev_mutex);
148 	list_del(&dev->dev_list);
149 	mutex_unlock(&atm_dev_mutex);
150 
151 	atm_dev_release_vccs(dev);
152 	atm_unregister_sysfs(dev);
153 	atm_proc_dev_deregister(dev);
154 
155 	atm_dev_put(dev);
156 }
157 EXPORT_SYMBOL(atm_dev_deregister);
158 
copy_aal_stats(struct k_atm_aal_stats * from,struct atm_aal_stats * to)159 static void copy_aal_stats(struct k_atm_aal_stats *from,
160     struct atm_aal_stats *to)
161 {
162 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
163 	__AAL_STAT_ITEMS
164 #undef __HANDLE_ITEM
165 }
166 
subtract_aal_stats(struct k_atm_aal_stats * from,struct atm_aal_stats * to)167 static void subtract_aal_stats(struct k_atm_aal_stats *from,
168     struct atm_aal_stats *to)
169 {
170 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
171 	__AAL_STAT_ITEMS
172 #undef __HANDLE_ITEM
173 }
174 
fetch_stats(struct atm_dev * dev,struct atm_dev_stats __user * arg,int zero)175 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg,
176 		       int zero)
177 {
178 	struct atm_dev_stats tmp;
179 	int error = 0;
180 
181 	copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
182 	copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
183 	copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
184 	if (arg)
185 		error = copy_to_user(arg, &tmp, sizeof(tmp));
186 	if (zero && !error) {
187 		subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
188 		subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
189 		subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
190 	}
191 	return error ? -EFAULT : 0;
192 }
193 
atm_getnames(void __user * buf,int __user * iobuf_len)194 int atm_getnames(void __user *buf, int __user *iobuf_len)
195 {
196 	int error, len, size = 0;
197 	struct atm_dev *dev;
198 	struct list_head *p;
199 	int *tmp_buf, *tmp_p;
200 
201 	if (get_user(len, iobuf_len))
202 		return -EFAULT;
203 	mutex_lock(&atm_dev_mutex);
204 	list_for_each(p, &atm_devs)
205 		size += sizeof(int);
206 	if (size > len) {
207 		mutex_unlock(&atm_dev_mutex);
208 		return -E2BIG;
209 	}
210 	tmp_buf = kmalloc(size, GFP_ATOMIC);
211 	if (!tmp_buf) {
212 		mutex_unlock(&atm_dev_mutex);
213 		return -ENOMEM;
214 	}
215 	tmp_p = tmp_buf;
216 	list_for_each_entry(dev, &atm_devs, dev_list) {
217 		*tmp_p++ = dev->number;
218 	}
219 	mutex_unlock(&atm_dev_mutex);
220 	error = ((copy_to_user(buf, tmp_buf, size)) ||
221 		 put_user(size, iobuf_len))
222 		? -EFAULT : 0;
223 	kfree(tmp_buf);
224 	return error;
225 }
226 
atm_dev_ioctl(unsigned int cmd,void __user * buf,int __user * sioc_len,int number,int compat)227 int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
228 		  int number, int compat)
229 {
230 	int error, len, size = 0;
231 	struct atm_dev *dev;
232 
233 	if (get_user(len, sioc_len))
234 		return -EFAULT;
235 
236 	dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
237 				      number);
238 	if (!dev)
239 		return -ENODEV;
240 
241 	switch (cmd) {
242 	case ATM_GETTYPE:
243 		size = strlen(dev->type) + 1;
244 		if (copy_to_user(buf, dev->type, size)) {
245 			error = -EFAULT;
246 			goto done;
247 		}
248 		break;
249 	case ATM_GETESI:
250 		size = ESI_LEN;
251 		if (copy_to_user(buf, dev->esi, size)) {
252 			error = -EFAULT;
253 			goto done;
254 		}
255 		break;
256 	case ATM_SETESI:
257 	{
258 		int i;
259 
260 		for (i = 0; i < ESI_LEN; i++)
261 			if (dev->esi[i]) {
262 				error = -EEXIST;
263 				goto done;
264 			}
265 	}
266 		fallthrough;
267 	case ATM_SETESIF:
268 	{
269 		unsigned char esi[ESI_LEN];
270 
271 		if (!capable(CAP_NET_ADMIN)) {
272 			error = -EPERM;
273 			goto done;
274 		}
275 		if (copy_from_user(esi, buf, ESI_LEN)) {
276 			error = -EFAULT;
277 			goto done;
278 		}
279 		memcpy(dev->esi, esi, ESI_LEN);
280 		error =  ESI_LEN;
281 		goto done;
282 	}
283 	case ATM_GETSTATZ:
284 		if (!capable(CAP_NET_ADMIN)) {
285 			error = -EPERM;
286 			goto done;
287 		}
288 		fallthrough;
289 	case ATM_GETSTAT:
290 		size = sizeof(struct atm_dev_stats);
291 		error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
292 		if (error)
293 			goto done;
294 		break;
295 	case ATM_GETCIRANGE:
296 		size = sizeof(struct atm_cirange);
297 		if (copy_to_user(buf, &dev->ci_range, size)) {
298 			error = -EFAULT;
299 			goto done;
300 		}
301 		break;
302 	case ATM_GETLINKRATE:
303 		size = sizeof(int);
304 		if (copy_to_user(buf, &dev->link_rate, size)) {
305 			error = -EFAULT;
306 			goto done;
307 		}
308 		break;
309 	case ATM_RSTADDR:
310 		if (!capable(CAP_NET_ADMIN)) {
311 			error = -EPERM;
312 			goto done;
313 		}
314 		atm_reset_addr(dev, ATM_ADDR_LOCAL);
315 		break;
316 	case ATM_ADDADDR:
317 	case ATM_DELADDR:
318 	case ATM_ADDLECSADDR:
319 	case ATM_DELLECSADDR:
320 	{
321 		struct sockaddr_atmsvc addr;
322 
323 		if (!capable(CAP_NET_ADMIN)) {
324 			error = -EPERM;
325 			goto done;
326 		}
327 
328 		if (copy_from_user(&addr, buf, sizeof(addr))) {
329 			error = -EFAULT;
330 			goto done;
331 		}
332 		if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
333 			error = atm_add_addr(dev, &addr,
334 					     (cmd == ATM_ADDADDR ?
335 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
336 		else
337 			error = atm_del_addr(dev, &addr,
338 					     (cmd == ATM_DELADDR ?
339 					      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
340 		goto done;
341 	}
342 	case ATM_GETADDR:
343 	case ATM_GETLECSADDR:
344 		error = atm_get_addr(dev, buf, len,
345 				     (cmd == ATM_GETADDR ?
346 				      ATM_ADDR_LOCAL : ATM_ADDR_LECS));
347 		if (error < 0)
348 			goto done;
349 		size = error;
350 		/* may return 0, but later on size == 0 means "don't
351 		   write the length" */
352 		error = put_user(size, sioc_len) ? -EFAULT : 0;
353 		goto done;
354 	case ATM_SETLOOP:
355 		if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
356 		    __ATM_LM_XTLOC((int) (unsigned long) buf) >
357 		    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
358 			error = -EINVAL;
359 			goto done;
360 		}
361 		fallthrough;
362 	case ATM_SETCIRANGE:
363 	case SONET_GETSTATZ:
364 	case SONET_SETDIAG:
365 	case SONET_CLRDIAG:
366 	case SONET_SETFRAMING:
367 		if (!capable(CAP_NET_ADMIN)) {
368 			error = -EPERM;
369 			goto done;
370 		}
371 		fallthrough;
372 	default:
373 		if (IS_ENABLED(CONFIG_COMPAT) && compat) {
374 #ifdef CONFIG_COMPAT
375 			if (!dev->ops->compat_ioctl) {
376 				error = -EINVAL;
377 				goto done;
378 			}
379 			size = dev->ops->compat_ioctl(dev, cmd, buf);
380 #endif
381 		} else {
382 			if (!dev->ops->ioctl) {
383 				error = -EINVAL;
384 				goto done;
385 			}
386 			size = dev->ops->ioctl(dev, cmd, buf);
387 		}
388 		if (size < 0) {
389 			error = (size == -ENOIOCTLCMD ? -ENOTTY : size);
390 			goto done;
391 		}
392 	}
393 
394 	if (size)
395 		error = put_user(size, sioc_len) ? -EFAULT : 0;
396 	else
397 		error = 0;
398 done:
399 	atm_dev_put(dev);
400 	return error;
401 }
402 
403 #ifdef CONFIG_PROC_FS
atm_dev_seq_start(struct seq_file * seq,loff_t * pos)404 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
405 {
406 	mutex_lock(&atm_dev_mutex);
407 	return seq_list_start_head(&atm_devs, *pos);
408 }
409 
atm_dev_seq_stop(struct seq_file * seq,void * v)410 void atm_dev_seq_stop(struct seq_file *seq, void *v)
411 {
412 	mutex_unlock(&atm_dev_mutex);
413 }
414 
atm_dev_seq_next(struct seq_file * seq,void * v,loff_t * pos)415 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
416 {
417 	return seq_list_next(v, &atm_devs, pos);
418 }
419 #endif
420