xref: /openbmc/linux/net/atm/resources.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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/delay.h>
20 #include <net/sock.h>	 /* for struct sock */
21 
22 #include "common.h"
23 #include "resources.h"
24 #include "addr.h"
25 
26 
27 LIST_HEAD(atm_devs);
28 DEFINE_SPINLOCK(atm_dev_lock);
29 
30 static struct atm_dev *__alloc_atm_dev(const char *type)
31 {
32 	struct atm_dev *dev;
33 
34 	dev = kmalloc(sizeof(*dev), GFP_KERNEL);
35 	if (!dev)
36 		return NULL;
37 	memset(dev, 0, sizeof(*dev));
38 	dev->type = type;
39 	dev->signal = ATM_PHY_SIG_UNKNOWN;
40 	dev->link_rate = ATM_OC3_PCR;
41 	spin_lock_init(&dev->lock);
42 	INIT_LIST_HEAD(&dev->local);
43 
44 	return dev;
45 }
46 
47 static void __free_atm_dev(struct atm_dev *dev)
48 {
49 	kfree(dev);
50 }
51 
52 static struct atm_dev *__atm_dev_lookup(int number)
53 {
54 	struct atm_dev *dev;
55 	struct list_head *p;
56 
57 	list_for_each(p, &atm_devs) {
58 		dev = list_entry(p, struct atm_dev, dev_list);
59 		if ((dev->ops) && (dev->number == number)) {
60 			atm_dev_hold(dev);
61 			return dev;
62 		}
63 	}
64 	return NULL;
65 }
66 
67 struct atm_dev *atm_dev_lookup(int number)
68 {
69 	struct atm_dev *dev;
70 
71 	spin_lock(&atm_dev_lock);
72 	dev = __atm_dev_lookup(number);
73 	spin_unlock(&atm_dev_lock);
74 	return dev;
75 }
76 
77 struct atm_dev *atm_dev_register(const char *type, const struct atmdev_ops *ops,
78 				 int number, unsigned long *flags)
79 {
80 	struct atm_dev *dev, *inuse;
81 
82 	dev = __alloc_atm_dev(type);
83 	if (!dev) {
84 		printk(KERN_ERR "atm_dev_register: no space for dev %s\n",
85 		    type);
86 		return NULL;
87 	}
88 	spin_lock(&atm_dev_lock);
89 	if (number != -1) {
90 		if ((inuse = __atm_dev_lookup(number))) {
91 			atm_dev_put(inuse);
92 			spin_unlock(&atm_dev_lock);
93 			__free_atm_dev(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 	atomic_set(&dev->refcnt, 1);
112 	list_add_tail(&dev->dev_list, &atm_devs);
113 	spin_unlock(&atm_dev_lock);
114 
115 	if (atm_proc_dev_register(dev) < 0) {
116 		printk(KERN_ERR "atm_dev_register: "
117 		       "atm_proc_dev_register failed for dev %s\n",
118 		       type);
119 		spin_lock(&atm_dev_lock);
120 		list_del(&dev->dev_list);
121 		spin_unlock(&atm_dev_lock);
122 		__free_atm_dev(dev);
123 		return NULL;
124 	}
125 
126 	return dev;
127 }
128 
129 
130 void atm_dev_deregister(struct atm_dev *dev)
131 {
132 	unsigned long warning_time;
133 
134 	atm_proc_dev_deregister(dev);
135 
136 	spin_lock(&atm_dev_lock);
137 	list_del(&dev->dev_list);
138 	spin_unlock(&atm_dev_lock);
139 
140         warning_time = jiffies;
141         while (atomic_read(&dev->refcnt) != 1) {
142                 msleep(250);
143                 if ((jiffies - warning_time) > 10 * HZ) {
144                         printk(KERN_EMERG "atm_dev_deregister: waiting for "
145                                "dev %d to become free. Usage count = %d\n",
146                                dev->number, atomic_read(&dev->refcnt));
147                         warning_time = jiffies;
148                 }
149         }
150 
151 	__free_atm_dev(dev);
152 }
153 
154 void shutdown_atm_dev(struct atm_dev *dev)
155 {
156 	if (atomic_read(&dev->refcnt) > 1) {
157 		set_bit(ATM_DF_CLOSE, &dev->flags);
158 		return;
159 	}
160 	if (dev->ops->dev_close)
161 		dev->ops->dev_close(dev);
162 	atm_dev_deregister(dev);
163 }
164 
165 
166 static void copy_aal_stats(struct k_atm_aal_stats *from,
167     struct atm_aal_stats *to)
168 {
169 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
170 	__AAL_STAT_ITEMS
171 #undef __HANDLE_ITEM
172 }
173 
174 
175 static void subtract_aal_stats(struct k_atm_aal_stats *from,
176     struct atm_aal_stats *to)
177 {
178 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
179 	__AAL_STAT_ITEMS
180 #undef __HANDLE_ITEM
181 }
182 
183 
184 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, int zero)
185 {
186 	struct atm_dev_stats tmp;
187 	int error = 0;
188 
189 	copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
190 	copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
191 	copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
192 	if (arg)
193 		error = copy_to_user(arg, &tmp, sizeof(tmp));
194 	if (zero && !error) {
195 		subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
196 		subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
197 		subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
198 	}
199 	return error ? -EFAULT : 0;
200 }
201 
202 
203 int atm_dev_ioctl(unsigned int cmd, void __user *arg)
204 {
205 	void __user *buf;
206 	int error, len, number, size = 0;
207 	struct atm_dev *dev;
208 	struct list_head *p;
209 	int *tmp_buf, *tmp_p;
210 	struct atm_iobuf __user *iobuf = arg;
211 	struct atmif_sioc __user *sioc = arg;
212 	switch (cmd) {
213 		case ATM_GETNAMES:
214 			if (get_user(buf, &iobuf->buffer))
215 				return -EFAULT;
216 			if (get_user(len, &iobuf->length))
217 				return -EFAULT;
218 			spin_lock(&atm_dev_lock);
219 			list_for_each(p, &atm_devs)
220 				size += sizeof(int);
221 			if (size > len) {
222 				spin_unlock(&atm_dev_lock);
223 				return -E2BIG;
224 			}
225 			tmp_buf = kmalloc(size, GFP_ATOMIC);
226 			if (!tmp_buf) {
227 				spin_unlock(&atm_dev_lock);
228 				return -ENOMEM;
229 			}
230 			tmp_p = tmp_buf;
231 			list_for_each(p, &atm_devs) {
232 				dev = list_entry(p, struct atm_dev, dev_list);
233 				*tmp_p++ = dev->number;
234 			}
235 			spin_unlock(&atm_dev_lock);
236 		        error = ((copy_to_user(buf, tmp_buf, size)) ||
237 					put_user(size, &iobuf->length))
238 						? -EFAULT : 0;
239 			kfree(tmp_buf);
240 			return error;
241 		default:
242 			break;
243 	}
244 
245 	if (get_user(buf, &sioc->arg))
246 		return -EFAULT;
247 	if (get_user(len, &sioc->length))
248 		return -EFAULT;
249 	if (get_user(number, &sioc->number))
250 		return -EFAULT;
251 
252 	if (!(dev = atm_dev_lookup(number)))
253 		return -ENODEV;
254 
255 	switch (cmd) {
256 		case ATM_GETTYPE:
257 			size = strlen(dev->type) + 1;
258 			if (copy_to_user(buf, dev->type, size)) {
259 				error = -EFAULT;
260 				goto done;
261 			}
262 			break;
263 		case ATM_GETESI:
264 			size = ESI_LEN;
265 			if (copy_to_user(buf, dev->esi, size)) {
266 				error = -EFAULT;
267 				goto done;
268 			}
269 			break;
270 		case ATM_SETESI:
271 			{
272 				int i;
273 
274 				for (i = 0; i < ESI_LEN; i++)
275 					if (dev->esi[i]) {
276 						error = -EEXIST;
277 						goto done;
278 					}
279 			}
280 			/* fall through */
281 		case ATM_SETESIF:
282 			{
283 				unsigned char esi[ESI_LEN];
284 
285 				if (!capable(CAP_NET_ADMIN)) {
286 					error = -EPERM;
287 					goto done;
288 				}
289 				if (copy_from_user(esi, buf, ESI_LEN)) {
290 					error = -EFAULT;
291 					goto done;
292 				}
293 				memcpy(dev->esi, esi, ESI_LEN);
294 				error =  ESI_LEN;
295 				goto done;
296 			}
297 		case ATM_GETSTATZ:
298 			if (!capable(CAP_NET_ADMIN)) {
299 				error = -EPERM;
300 				goto done;
301 			}
302 			/* fall through */
303 		case ATM_GETSTAT:
304 			size = sizeof(struct atm_dev_stats);
305 			error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
306 			if (error)
307 				goto done;
308 			break;
309 		case ATM_GETCIRANGE:
310 			size = sizeof(struct atm_cirange);
311 			if (copy_to_user(buf, &dev->ci_range, size)) {
312 				error = -EFAULT;
313 				goto done;
314 			}
315 			break;
316 		case ATM_GETLINKRATE:
317 			size = sizeof(int);
318 			if (copy_to_user(buf, &dev->link_rate, size)) {
319 				error = -EFAULT;
320 				goto done;
321 			}
322 			break;
323 		case ATM_RSTADDR:
324 			if (!capable(CAP_NET_ADMIN)) {
325 				error = -EPERM;
326 				goto done;
327 			}
328 			atm_reset_addr(dev);
329 			break;
330 		case ATM_ADDADDR:
331 		case ATM_DELADDR:
332 			if (!capable(CAP_NET_ADMIN)) {
333 				error = -EPERM;
334 				goto done;
335 			}
336 			{
337 				struct sockaddr_atmsvc addr;
338 
339 				if (copy_from_user(&addr, buf, sizeof(addr))) {
340 					error = -EFAULT;
341 					goto done;
342 				}
343 				if (cmd == ATM_ADDADDR)
344 					error = atm_add_addr(dev, &addr);
345 				else
346 					error = atm_del_addr(dev, &addr);
347 				goto done;
348 			}
349 		case ATM_GETADDR:
350 			error = atm_get_addr(dev, buf, len);
351 			if (error < 0)
352 				goto done;
353 			size = error;
354 			/* may return 0, but later on size == 0 means "don't
355 			   write the length" */
356 			error = put_user(size, &sioc->length)
357 				? -EFAULT : 0;
358 			goto done;
359 		case ATM_SETLOOP:
360 			if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
361 			    __ATM_LM_XTLOC((int) (unsigned long) buf) >
362 			    __ATM_LM_XTRMT((int) (unsigned long) buf)) {
363 				error = -EINVAL;
364 				goto done;
365 			}
366 			/* fall through */
367 		case ATM_SETCIRANGE:
368 		case SONET_GETSTATZ:
369 		case SONET_SETDIAG:
370 		case SONET_CLRDIAG:
371 		case SONET_SETFRAMING:
372 			if (!capable(CAP_NET_ADMIN)) {
373 				error = -EPERM;
374 				goto done;
375 			}
376 			/* fall through */
377 		default:
378 			if (!dev->ops->ioctl) {
379 				error = -EINVAL;
380 				goto done;
381 			}
382 			size = dev->ops->ioctl(dev, cmd, buf);
383 			if (size < 0) {
384 				error = (size == -ENOIOCTLCMD ? -EINVAL : size);
385 				goto done;
386 			}
387 	}
388 
389 	if (size)
390 		error = put_user(size, &sioc->length)
391 			? -EFAULT : 0;
392 	else
393 		error = 0;
394 done:
395 	atm_dev_put(dev);
396 	return error;
397 }
398 
399 static __inline__ void *dev_get_idx(loff_t left)
400 {
401 	struct list_head *p;
402 
403 	list_for_each(p, &atm_devs) {
404 		if (!--left)
405 			break;
406 	}
407 	return (p != &atm_devs) ? p : NULL;
408 }
409 
410 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
411 {
412  	spin_lock(&atm_dev_lock);
413 	return *pos ? dev_get_idx(*pos) : (void *) 1;
414 }
415 
416 void atm_dev_seq_stop(struct seq_file *seq, void *v)
417 {
418  	spin_unlock(&atm_dev_lock);
419 }
420 
421 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
422 {
423 	++*pos;
424 	v = (v == (void *)1) ? atm_devs.next : ((struct list_head *)v)->next;
425 	return (v == &atm_devs) ? NULL : v;
426 }
427 
428 
429 EXPORT_SYMBOL(atm_dev_register);
430 EXPORT_SYMBOL(atm_dev_deregister);
431 EXPORT_SYMBOL(atm_dev_lookup);
432 EXPORT_SYMBOL(shutdown_atm_dev);
433