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
32LIST_HEAD(atm_devs);
33DEFINE_MUTEX(atm_dev_mutex);
34
35static struct atm_dev *__alloc_atm_dev(const char *type)
36{
37 struct atm_dev *dev;
38
39 dev = kzalloc(size: 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(list: &dev->local);
47 INIT_LIST_HEAD(list: &dev->lecs);
48
49 return dev;
50}
51
52static 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
65struct 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(lock: &atm_dev_mutex);
72 return dev;
73}
74EXPORT_SYMBOL(atm_dev_lookup);
75
76struct 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(dev: inuse);
92 mutex_unlock(lock: &atm_dev_mutex);
93 kfree(objp: dev);
94 return NULL;
95 }
96 dev->number = number;
97 } else {
98 dev->number = 0;
99 while ((inuse = __atm_dev_lookup(number: dev->number))) {
100 atm_dev_put(dev: 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(r: &dev->refcnt, n: 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(adev: 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(new: &dev->dev_list, head: &atm_devs);
125
126out:
127 mutex_unlock(lock: &atm_dev_mutex);
128 return dev;
129
130out_fail:
131 kfree(objp: dev);
132 dev = NULL;
133 goto out;
134}
135EXPORT_SYMBOL(atm_dev_register);
136
137void atm_dev_deregister(struct atm_dev *dev)
138{
139 BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
140 set_bit(nr: ATM_DF_REMOVED, addr: &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(entry: &dev->dev_list);
149 mutex_unlock(lock: &atm_dev_mutex);
150
151 atm_dev_release_vccs(dev);
152 atm_unregister_sysfs(adev: dev);
153 atm_proc_dev_deregister(dev);
154
155 atm_dev_put(dev);
156}
157EXPORT_SYMBOL(atm_dev_deregister);
158
159static 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
167static 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
175static 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(from: &dev->stats.aal0, to: &tmp.aal0);
182 copy_aal_stats(from: &dev->stats.aal34, to: &tmp.aal34);
183 copy_aal_stats(from: &dev->stats.aal5, to: &tmp.aal5);
184 if (arg)
185 error = copy_to_user(to: arg, from: &tmp, n: sizeof(tmp));
186 if (zero && !error) {
187 subtract_aal_stats(from: &dev->stats.aal0, to: &tmp.aal0);
188 subtract_aal_stats(from: &dev->stats.aal34, to: &tmp.aal34);
189 subtract_aal_stats(from: &dev->stats.aal5, to: &tmp.aal5);
190 }
191 return error ? -EFAULT : 0;
192}
193
194int 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(lock: &atm_dev_mutex);
208 return -E2BIG;
209 }
210 tmp_buf = kmalloc(size, GFP_ATOMIC);
211 if (!tmp_buf) {
212 mutex_unlock(lock: &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(lock: &atm_dev_mutex);
220 error = ((copy_to_user(to: buf, from: tmp_buf, n: size)) ||
221 put_user(size, iobuf_len))
222 ? -EFAULT : 0;
223 kfree(objp: tmp_buf);
224 return error;
225}
226
227int 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(to: buf, from: dev->type, n: size)) {
245 error = -EFAULT;
246 goto done;
247 }
248 break;
249 case ATM_GETESI:
250 size = ESI_LEN;
251 if (copy_to_user(to: buf, from: dev->esi, n: 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(to: esi, from: 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, arg: buf, zero: 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(to: buf, from: &dev->ci_range, n: size)) {
298 error = -EFAULT;
299 goto done;
300 }
301 break;
302 case ATM_GETLINKRATE:
303 size = sizeof(int);
304 if (copy_to_user(to: buf, from: &dev->link_rate, n: 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, type: 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(to: &addr, from: buf, n: sizeof(addr))) {
329 error = -EFAULT;
330 goto done;
331 }
332 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
333 error = atm_add_addr(dev, addr: &addr,
334 type: (cmd == ATM_ADDADDR ?
335 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
336 else
337 error = atm_del_addr(dev, addr: &addr,
338 type: (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, size: len,
345 type: (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;
398done:
399 atm_dev_put(dev);
400 return error;
401}
402
403#ifdef CONFIG_PROC_FS
404void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
405{
406 mutex_lock(&atm_dev_mutex);
407 return seq_list_start_head(head: &atm_devs, pos: *pos);
408}
409
410void atm_dev_seq_stop(struct seq_file *seq, void *v)
411{
412 mutex_unlock(lock: &atm_dev_mutex);
413}
414
415void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
416{
417 return seq_list_next(v, head: &atm_devs, ppos: pos);
418}
419#endif
420

source code of linux/net/atm/resources.c