1 /*****************************************************************************
2 * wanmain.c	WAN Multiprotocol Router Module. Main code.
3 *
4 *		This module is completely hardware-independent and provides
5 *		the following common services for the WAN Link Drivers:
6 *		 o WAN device management (registering, unregistering)
7 *		 o Network interface management
8 *		 o Physical connection management (dial-up, incoming calls)
9 *		 o Logical connection management (switched virtual circuits)
10 *		 o Protocol encapsulation/decapsulation
11 *
12 * Author:	Gideon Hack
13 *
14 * Copyright:	(c) 1995-1999 Sangoma Technologies Inc.
15 *
16 *		This program is free software; you can redistribute it and/or
17 *		modify it under the terms of the GNU General Public License
18 *		as published by the Free Software Foundation; either version
19 *		2 of the License, or (at your option) any later version.
20 * ============================================================================
21 * Nov 24, 2000  Nenad Corbic	Updated for 2.4.X kernels
22 * Nov 07, 2000  Nenad Corbic	Fixed the Mulit-Port PPP for kernels 2.2.16 and
23 *  				greater.
24 * Aug 2,  2000  Nenad Corbic	Block the Multi-Port PPP from running on
25 *  			        kernels 2.2.16 or greater.  The SyncPPP
26 *  			        has changed.
27 * Jul 13, 2000  Nenad Corbic	Added SyncPPP support
28 * 				Added extra debugging in device_setup().
29 * Oct 01, 1999  Gideon Hack     Update for s514 PCI card
30 * Dec 27, 1996	Gene Kozin	Initial version (based on Sangoma's WANPIPE)
31 * Jan 16, 1997	Gene Kozin	router_devlist made public
32 * Jan 31, 1997  Alan Cox	Hacked it about a bit for 2.1
33 * Jun 27, 1997  Alan Cox	realigned with vendor code
34 * Oct 15, 1997  Farhan Thawar   changed wan_encapsulate to add a pad byte of 0
35 * Apr 20, 1998	Alan Cox	Fixed 2.1 symbols
36 * May 17, 1998  K. Baranowski	Fixed SNAP encapsulation in wan_encapsulate
37 * Dec 15, 1998  Arnaldo Melo    support for firmwares of up to 128000 bytes
38 *                               check wandev->setup return value
39 * Dec 22, 1998  Arnaldo Melo    vmalloc/vfree used in device_setup to allocate
40 *                               kernel memory and copy configuration data to
41 *                               kernel space (for big firmwares)
42 * Jun 02, 1999  Gideon Hack	Updates for Linux 2.0.X and 2.2.X kernels.
43 *****************************************************************************/
44 
45 #include <linux/stddef.h>	/* offsetof(), etc. */
46 #include <linux/capability.h>
47 #include <linux/errno.h>	/* return codes */
48 #include <linux/kernel.h>
49 #include <linux/module.h>	/* support for loadable modules */
50 #include <linux/slab.h>		/* kmalloc(), kfree() */
51 #include <linux/mutex.h>
52 #include <linux/mm.h>
53 #include <linux/string.h>	/* inline mem*, str* functions */
54 
55 #include <asm/byteorder.h>	/* htons(), etc. */
56 #include <linux/wanrouter.h>	/* WAN router API definitions */
57 
58 #include <linux/vmalloc.h>	/* vmalloc, vfree */
59 #include <asm/uaccess.h>        /* copy_to/from_user */
60 #include <linux/init.h>         /* __initfunc et al. */
61 
62 #define DEV_TO_SLAVE(dev)	(*((struct net_device **)netdev_priv(dev)))
63 
64 /*
65  * 	Function Prototypes
66  */
67 
68 /*
69  *	WAN device IOCTL handlers
70  */
71 
72 static DEFINE_MUTEX(wanrouter_mutex);
73 static int wanrouter_device_setup(struct wan_device *wandev,
74 				  wandev_conf_t __user *u_conf);
75 static int wanrouter_device_stat(struct wan_device *wandev,
76 				 wandev_stat_t __user *u_stat);
77 static int wanrouter_device_shutdown(struct wan_device *wandev);
78 static int wanrouter_device_new_if(struct wan_device *wandev,
79 				   wanif_conf_t __user *u_conf);
80 static int wanrouter_device_del_if(struct wan_device *wandev,
81 				   char __user *u_name);
82 
83 /*
84  *	Miscellaneous
85  */
86 
87 static struct wan_device *wanrouter_find_device(char *name);
88 static int wanrouter_delete_interface(struct wan_device *wandev, char *name);
89 static void lock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
90 	__acquires(lock);
91 static void unlock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
92 	__releases(lock);
93 
94 
95 
96 /*
97  *	Global Data
98  */
99 
100 static char wanrouter_fullname[]  = "Sangoma WANPIPE Router";
101 static char wanrouter_copyright[] = "(c) 1995-2000 Sangoma Technologies Inc.";
102 static char wanrouter_modname[] = ROUTER_NAME; /* short module name */
103 struct wan_device* wanrouter_router_devlist; /* list of registered devices */
104 
105 /*
106  *	Organize Unique Identifiers for encapsulation/decapsulation
107  */
108 
109 #if 0
110 static unsigned char wanrouter_oui_ether[] = { 0x00, 0x00, 0x00 };
111 static unsigned char wanrouter_oui_802_2[] = { 0x00, 0x80, 0xC2 };
112 #endif
113 
wanrouter_init(void)114 static int __init wanrouter_init(void)
115 {
116 	int err;
117 
118 	printk(KERN_INFO "%s v%u.%u %s\n",
119 	       wanrouter_fullname, ROUTER_VERSION, ROUTER_RELEASE,
120 	       wanrouter_copyright);
121 
122 	err = wanrouter_proc_init();
123 	if (err)
124 		printk(KERN_INFO "%s: can't create entry in proc filesystem!\n",
125 		       wanrouter_modname);
126 
127 	return err;
128 }
129 
wanrouter_cleanup(void)130 static void __exit wanrouter_cleanup (void)
131 {
132 	wanrouter_proc_cleanup();
133 }
134 
135 /*
136  * This is just plain dumb.  We should move the bugger to drivers/net/wan,
137  * slap it first in directory and make it module_init().  The only reason
138  * for subsys_initcall() here is that net goes after drivers (why, BTW?)
139  */
140 subsys_initcall(wanrouter_init);
141 module_exit(wanrouter_cleanup);
142 
143 /*
144  * 	Kernel APIs
145  */
146 
147 /*
148  * 	Register WAN device.
149  * 	o verify device credentials
150  * 	o create an entry for the device in the /proc/net/router directory
151  * 	o initialize internally maintained fields of the wan_device structure
152  * 	o link device data space to a singly-linked list
153  * 	o if it's the first device, then start kernel 'thread'
154  * 	o increment module use count
155  *
156  * 	Return:
157  *	0	Ok
158  *	< 0	error.
159  *
160  * 	Context:	process
161  */
162 
163 
register_wan_device(struct wan_device * wandev)164 int register_wan_device(struct wan_device *wandev)
165 {
166 	int err, namelen;
167 
168 	if ((wandev == NULL) || (wandev->magic != ROUTER_MAGIC) ||
169 	    (wandev->name == NULL))
170 		return -EINVAL;
171 
172 	namelen = strlen(wandev->name);
173 	if (!namelen || (namelen > WAN_DRVNAME_SZ))
174 		return -EINVAL;
175 
176 	if (wanrouter_find_device(wandev->name))
177 		return -EEXIST;
178 
179 #ifdef WANDEBUG
180 	printk(KERN_INFO "%s: registering WAN device %s\n",
181 	       wanrouter_modname, wandev->name);
182 #endif
183 
184 	/*
185 	 *	Register /proc directory entry
186 	 */
187 	err = wanrouter_proc_add(wandev);
188 	if (err) {
189 		printk(KERN_INFO
190 			"%s: can't create /proc/net/router/%s entry!\n",
191 			wanrouter_modname, wandev->name);
192 		return err;
193 	}
194 
195 	/*
196 	 *	Initialize fields of the wan_device structure maintained by the
197 	 *	router and update local data.
198 	 */
199 
200 	wandev->ndev = 0;
201 	wandev->dev  = NULL;
202 	wandev->next = wanrouter_router_devlist;
203 	wanrouter_router_devlist = wandev;
204 	return 0;
205 }
206 
207 /*
208  *	Unregister WAN device.
209  *	o shut down device
210  *	o unlink device data space from the linked list
211  *	o delete device entry in the /proc/net/router directory
212  *	o decrement module use count
213  *
214  *	Return:		0	Ok
215  *			<0	error.
216  *	Context:	process
217  */
218 
219 
unregister_wan_device(char * name)220 int unregister_wan_device(char *name)
221 {
222 	struct wan_device *wandev, *prev;
223 
224 	if (name == NULL)
225 		return -EINVAL;
226 
227 	for (wandev = wanrouter_router_devlist, prev = NULL;
228 		wandev && strcmp(wandev->name, name);
229 		prev = wandev, wandev = wandev->next)
230 		;
231 	if (wandev == NULL)
232 		return -ENODEV;
233 
234 #ifdef WANDEBUG
235 	printk(KERN_INFO "%s: unregistering WAN device %s\n",
236 	       wanrouter_modname, name);
237 #endif
238 
239 	if (wandev->state != WAN_UNCONFIGURED)
240 		wanrouter_device_shutdown(wandev);
241 
242 	if (prev)
243 		prev->next = wandev->next;
244 	else
245 		wanrouter_router_devlist = wandev->next;
246 
247 	wanrouter_proc_delete(wandev);
248 	return 0;
249 }
250 
251 #if 0
252 
253 /*
254  *	Encapsulate packet.
255  *
256  *	Return:	encapsulation header size
257  *		< 0	- unsupported Ethertype
258  *
259  *	Notes:
260  *	1. This function may be called on interrupt context.
261  */
262 
263 
264 int wanrouter_encapsulate(struct sk_buff *skb, struct net_device *dev,
265 			  unsigned short type)
266 {
267 	int hdr_len = 0;
268 
269 	switch (type) {
270 	case ETH_P_IP:		/* IP datagram encapsulation */
271 		hdr_len += 1;
272 		skb_push(skb, 1);
273 		skb->data[0] = NLPID_IP;
274 		break;
275 
276 	case ETH_P_IPX:		/* SNAP encapsulation */
277 	case ETH_P_ARP:
278 		hdr_len += 7;
279 		skb_push(skb, 7);
280 		skb->data[0] = 0;
281 		skb->data[1] = NLPID_SNAP;
282 		skb_copy_to_linear_data_offset(skb, 2, wanrouter_oui_ether,
283 					       sizeof(wanrouter_oui_ether));
284 		*((unsigned short*)&skb->data[5]) = htons(type);
285 		break;
286 
287 	default:		/* Unknown packet type */
288 		printk(KERN_INFO
289 			"%s: unsupported Ethertype 0x%04X on interface %s!\n",
290 			wanrouter_modname, type, dev->name);
291 		hdr_len = -EINVAL;
292 	}
293 	return hdr_len;
294 }
295 
296 
297 /*
298  *	Decapsulate packet.
299  *
300  *	Return:	Ethertype (in network order)
301  *			0	unknown encapsulation
302  *
303  *	Notes:
304  *	1. This function may be called on interrupt context.
305  */
306 
307 
308 __be16 wanrouter_type_trans(struct sk_buff *skb, struct net_device *dev)
309 {
310 	int cnt = skb->data[0] ? 0 : 1;	/* there may be a pad present */
311 	__be16 ethertype;
312 
313 	switch (skb->data[cnt]) {
314 	case NLPID_IP:		/* IP datagramm */
315 		ethertype = htons(ETH_P_IP);
316 		cnt += 1;
317 		break;
318 
319 	case NLPID_SNAP:	/* SNAP encapsulation */
320 		if (memcmp(&skb->data[cnt + 1], wanrouter_oui_ether,
321 			   sizeof(wanrouter_oui_ether))){
322 			printk(KERN_INFO
323 				"%s: unsupported SNAP OUI %02X-%02X-%02X "
324 				"on interface %s!\n", wanrouter_modname,
325 				skb->data[cnt+1], skb->data[cnt+2],
326 				skb->data[cnt+3], dev->name);
327 			return 0;
328 		}
329 		ethertype = *((__be16*)&skb->data[cnt+4]);
330 		cnt += 6;
331 		break;
332 
333 	/* add other protocols, e.g. CLNP, ESIS, ISIS, if needed */
334 
335 	default:
336 		printk(KERN_INFO
337 			"%s: unsupported NLPID 0x%02X on interface %s!\n",
338 			wanrouter_modname, skb->data[cnt], dev->name);
339 		return 0;
340 	}
341 	skb->protocol = ethertype;
342 	skb->pkt_type = PACKET_HOST;	/*	Physically point to point */
343 	skb_pull(skb, cnt);
344 	skb_reset_mac_header(skb);
345 	return ethertype;
346 }
347 
348 #endif  /*  0  */
349 
350 /*
351  *	WAN device IOCTL.
352  *	o find WAN device associated with this node
353  *	o execute requested action or pass command to the device driver
354  */
355 
wanrouter_ioctl(struct file * file,unsigned int cmd,unsigned long arg)356 long wanrouter_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
357 {
358 	struct inode *inode = file->f_path.dentry->d_inode;
359 	int err = 0;
360 	struct proc_dir_entry *dent;
361 	struct wan_device *wandev;
362 	void __user *data = (void __user *)arg;
363 
364 	if (!capable(CAP_NET_ADMIN))
365 		return -EPERM;
366 
367 	if ((cmd >> 8) != ROUTER_IOCTL)
368 		return -EINVAL;
369 
370 	dent = PDE(inode);
371 	if ((dent == NULL) || (dent->data == NULL))
372 		return -EINVAL;
373 
374 	wandev = dent->data;
375 	if (wandev->magic != ROUTER_MAGIC)
376 		return -EINVAL;
377 
378 	mutex_lock(&wanrouter_mutex);
379 	switch (cmd) {
380 	case ROUTER_SETUP:
381 		err = wanrouter_device_setup(wandev, data);
382 		break;
383 
384 	case ROUTER_DOWN:
385 		err = wanrouter_device_shutdown(wandev);
386 		break;
387 
388 	case ROUTER_STAT:
389 		err = wanrouter_device_stat(wandev, data);
390 		break;
391 
392 	case ROUTER_IFNEW:
393 		err = wanrouter_device_new_if(wandev, data);
394 		break;
395 
396 	case ROUTER_IFDEL:
397 		err = wanrouter_device_del_if(wandev, data);
398 		break;
399 
400 	case ROUTER_IFSTAT:
401 		break;
402 
403 	default:
404 		if ((cmd >= ROUTER_USER) &&
405 		    (cmd <= ROUTER_USER_MAX) &&
406 		    wandev->ioctl)
407 			err = wandev->ioctl(wandev, cmd, arg);
408 		else err = -EINVAL;
409 	}
410 	mutex_unlock(&wanrouter_mutex);
411 	return err;
412 }
413 
414 /*
415  *	WAN Driver IOCTL Handlers
416  */
417 
418 /*
419  *	Setup WAN link device.
420  *	o verify user address space
421  *	o allocate kernel memory and copy configuration data to kernel space
422  *	o if configuration data includes extension, copy it to kernel space too
423  *	o call driver's setup() entry point
424  */
425 
wanrouter_device_setup(struct wan_device * wandev,wandev_conf_t __user * u_conf)426 static int wanrouter_device_setup(struct wan_device *wandev,
427 				  wandev_conf_t __user *u_conf)
428 {
429 	void *data = NULL;
430 	wandev_conf_t *conf;
431 	int err = -EINVAL;
432 
433 	if (wandev->setup == NULL) {	/* Nothing to do ? */
434 		printk(KERN_INFO "%s: ERROR, No setup script: wandev->setup()\n",
435 				wandev->name);
436 		return 0;
437 	}
438 
439 	conf = kmalloc(sizeof(wandev_conf_t), GFP_KERNEL);
440 	if (conf == NULL){
441 		printk(KERN_INFO "%s: ERROR, Failed to allocate kernel memory !\n",
442 				wandev->name);
443 		return -ENOBUFS;
444 	}
445 
446 	if (copy_from_user(conf, u_conf, sizeof(wandev_conf_t))) {
447 		printk(KERN_INFO "%s: Failed to copy user config data to kernel space!\n",
448 				wandev->name);
449 		kfree(conf);
450 		return -EFAULT;
451 	}
452 
453 	if (conf->magic != ROUTER_MAGIC) {
454 		kfree(conf);
455 		printk(KERN_INFO "%s: ERROR, Invalid MAGIC Number\n",
456 				wandev->name);
457 		return -EINVAL;
458 	}
459 
460 	if (conf->data_size && conf->data) {
461 		if (conf->data_size > 128000) {
462 			printk(KERN_INFO
463 			    "%s: ERROR, Invalid firmware data size %i !\n",
464 					wandev->name, conf->data_size);
465 			kfree(conf);
466 			return -EINVAL;
467 		}
468 
469 		data = vmalloc(conf->data_size);
470 		if (!data) {
471 			printk(KERN_INFO
472 				"%s: ERROR, Failed allocate kernel memory !\n",
473 				wandev->name);
474 			kfree(conf);
475 			return -ENOBUFS;
476 		}
477 		if (!copy_from_user(data, conf->data, conf->data_size)) {
478 			conf->data = data;
479 			err = wandev->setup(wandev, conf);
480 		} else {
481 			printk(KERN_INFO
482 			     "%s: ERROR, Failed to copy from user data !\n",
483 			       wandev->name);
484 			err = -EFAULT;
485 		}
486 		vfree(data);
487 	} else {
488 		printk(KERN_INFO
489 		    "%s: ERROR, No firmware found ! Firmware size = %i !\n",
490 				wandev->name, conf->data_size);
491 	}
492 
493 	kfree(conf);
494 	return err;
495 }
496 
497 /*
498  *	Shutdown WAN device.
499  *	o delete all not opened logical channels for this device
500  *	o call driver's shutdown() entry point
501  */
502 
wanrouter_device_shutdown(struct wan_device * wandev)503 static int wanrouter_device_shutdown(struct wan_device *wandev)
504 {
505 	struct net_device *dev;
506 	int err=0;
507 
508 	if (wandev->state == WAN_UNCONFIGURED)
509 		return 0;
510 
511 	printk(KERN_INFO "\n%s: Shutting Down!\n",wandev->name);
512 
513 	for (dev = wandev->dev; dev;) {
514 		err = wanrouter_delete_interface(wandev, dev->name);
515 		if (err)
516 			return err;
517 		/* The above function deallocates the current dev
518 		 * structure. Therefore, we cannot use netdev_priv(dev)
519 		 * as the next element: wandev->dev points to the
520 		 * next element */
521 		dev = wandev->dev;
522 	}
523 
524 	if (wandev->ndev)
525 		return -EBUSY;	/* there are opened interfaces  */
526 
527 	if (wandev->shutdown)
528 		err=wandev->shutdown(wandev);
529 
530 	return err;
531 }
532 
533 /*
534  *	Get WAN device status & statistics.
535  */
536 
wanrouter_device_stat(struct wan_device * wandev,wandev_stat_t __user * u_stat)537 static int wanrouter_device_stat(struct wan_device *wandev,
538 				 wandev_stat_t __user *u_stat)
539 {
540 	wandev_stat_t stat;
541 
542 	memset(&stat, 0, sizeof(stat));
543 
544 	/* Ask device driver to update device statistics */
545 	if ((wandev->state != WAN_UNCONFIGURED) && wandev->update)
546 		wandev->update(wandev);
547 
548 	/* Fill out structure */
549 	stat.ndev  = wandev->ndev;
550 	stat.state = wandev->state;
551 
552 	if (copy_to_user(u_stat, &stat, sizeof(stat)))
553 		return -EFAULT;
554 
555 	return 0;
556 }
557 
558 /*
559  *	Create new WAN interface.
560  *	o verify user address space
561  *	o copy configuration data to kernel address space
562  *	o allocate network interface data space
563  *	o call driver's new_if() entry point
564  *	o make sure there is no interface name conflict
565  *	o register network interface
566  */
567 
wanrouter_device_new_if(struct wan_device * wandev,wanif_conf_t __user * u_conf)568 static int wanrouter_device_new_if(struct wan_device *wandev,
569 				   wanif_conf_t __user *u_conf)
570 {
571 	wanif_conf_t *cnf;
572 	struct net_device *dev = NULL;
573 	int err;
574 
575 	if ((wandev->state == WAN_UNCONFIGURED) || (wandev->new_if == NULL))
576 		return -ENODEV;
577 
578 	cnf = kmalloc(sizeof(wanif_conf_t), GFP_KERNEL);
579 	if (!cnf)
580 		return -ENOBUFS;
581 
582 	err = -EFAULT;
583 	if (copy_from_user(cnf, u_conf, sizeof(wanif_conf_t)))
584 		goto out;
585 
586 	err = -EINVAL;
587 	if (cnf->magic != ROUTER_MAGIC)
588 		goto out;
589 
590 	if (cnf->config_id == WANCONFIG_MPPP) {
591 		printk(KERN_INFO "%s: Wanpipe Mulit-Port PPP support has not been compiled in!\n",
592 				wandev->name);
593 		err = -EPROTONOSUPPORT;
594 		goto out;
595 	} else {
596 		err = wandev->new_if(wandev, dev, cnf);
597 	}
598 
599 	if (!err) {
600 		/* Register network interface. This will invoke init()
601 		 * function supplied by the driver.  If device registered
602 		 * successfully, add it to the interface list.
603 		 */
604 
605 		if (dev->name == NULL) {
606 			err = -EINVAL;
607 		} else {
608 
609 			#ifdef WANDEBUG
610 			printk(KERN_INFO "%s: registering interface %s...\n",
611 				wanrouter_modname, dev->name);
612 			#endif
613 
614 			err = register_netdev(dev);
615 			if (!err) {
616 				struct net_device *slave = NULL;
617 				unsigned long smp_flags=0;
618 
619 				lock_adapter_irq(&wandev->lock, &smp_flags);
620 
621 				if (wandev->dev == NULL) {
622 					wandev->dev = dev;
623 				} else {
624 					for (slave=wandev->dev;
625 					     DEV_TO_SLAVE(slave);
626 					     slave = DEV_TO_SLAVE(slave))
627 						DEV_TO_SLAVE(slave) = dev;
628 				}
629 				++wandev->ndev;
630 
631 				unlock_adapter_irq(&wandev->lock, &smp_flags);
632 				err = 0;	/* done !!! */
633 				goto out;
634 			}
635 		}
636 		if (wandev->del_if)
637 			wandev->del_if(wandev, dev);
638 		free_netdev(dev);
639 	}
640 
641 out:
642 	kfree(cnf);
643 	return err;
644 }
645 
646 
647 /*
648  *	Delete WAN logical channel.
649  *	 o verify user address space
650  *	 o copy configuration data to kernel address space
651  */
652 
wanrouter_device_del_if(struct wan_device * wandev,char __user * u_name)653 static int wanrouter_device_del_if(struct wan_device *wandev, char __user *u_name)
654 {
655 	char name[WAN_IFNAME_SZ + 1];
656 	int err = 0;
657 
658 	if (wandev->state == WAN_UNCONFIGURED)
659 		return -ENODEV;
660 
661 	memset(name, 0, sizeof(name));
662 
663 	if (copy_from_user(name, u_name, WAN_IFNAME_SZ))
664 		return -EFAULT;
665 
666 	err = wanrouter_delete_interface(wandev, name);
667 	if (err)
668 		return err;
669 
670 	/* If last interface being deleted, shutdown card
671 	 * This helps with administration at leaf nodes
672 	 * (You can tell if the person at the other end of the phone
673 	 * has an interface configured) and avoids DoS vulnerabilities
674 	 * in binary driver files - this fixes a problem with the current
675 	 * Sangoma driver going into strange states when all the network
676 	 * interfaces are deleted and the link irrecoverably disconnected.
677 	 */
678 
679 	if (!wandev->ndev && wandev->shutdown)
680 		err = wandev->shutdown(wandev);
681 
682 	return err;
683 }
684 
685 /*
686  *	Miscellaneous Functions
687  */
688 
689 /*
690  *	Find WAN device by name.
691  *	Return pointer to the WAN device data space or NULL if device not found.
692  */
693 
wanrouter_find_device(char * name)694 static struct wan_device *wanrouter_find_device(char *name)
695 {
696 	struct wan_device *wandev;
697 
698 	for (wandev = wanrouter_router_devlist;
699 	     wandev && strcmp(wandev->name, name);
700 		wandev = wandev->next);
701 	return wandev;
702 }
703 
704 /*
705  *	Delete WAN logical channel identified by its name.
706  *	o find logical channel by its name
707  *	o call driver's del_if() entry point
708  *	o unregister network interface
709  *	o unlink channel data space from linked list of channels
710  *	o release channel data space
711  *
712  *	Return:	0		success
713  *		-ENODEV		channel not found.
714  *		-EBUSY		interface is open
715  *
716  *	Note: If (force != 0), then device will be destroyed even if interface
717  *	associated with it is open. It's caller's responsibility to make
718  *	sure that opened interfaces are not removed!
719  */
720 
wanrouter_delete_interface(struct wan_device * wandev,char * name)721 static int wanrouter_delete_interface(struct wan_device *wandev, char *name)
722 {
723 	struct net_device *dev = NULL, *prev = NULL;
724 	unsigned long smp_flags=0;
725 
726 	lock_adapter_irq(&wandev->lock, &smp_flags);
727 	dev = wandev->dev;
728 	prev = NULL;
729 	while (dev && strcmp(name, dev->name)) {
730 		struct net_device **slave = netdev_priv(dev);
731 		prev = dev;
732 		dev = *slave;
733 	}
734 	unlock_adapter_irq(&wandev->lock, &smp_flags);
735 
736 	if (dev == NULL)
737 		return -ENODEV;	/* interface not found */
738 
739 	if (netif_running(dev))
740 		return -EBUSY;	/* interface in use */
741 
742 	if (wandev->del_if)
743 		wandev->del_if(wandev, dev);
744 
745 	lock_adapter_irq(&wandev->lock, &smp_flags);
746 	if (prev) {
747 		struct net_device **prev_slave = netdev_priv(prev);
748 		struct net_device **slave = netdev_priv(dev);
749 
750 		*prev_slave = *slave;
751 	} else {
752 		struct net_device **slave = netdev_priv(dev);
753 		wandev->dev = *slave;
754 	}
755 	--wandev->ndev;
756 	unlock_adapter_irq(&wandev->lock, &smp_flags);
757 
758 	printk(KERN_INFO "%s: unregistering '%s'\n", wandev->name, dev->name);
759 
760 	unregister_netdev(dev);
761 
762 	free_netdev(dev);
763 
764 	return 0;
765 }
766 
lock_adapter_irq(spinlock_t * lock,unsigned long * smp_flags)767 static void lock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
768 	__acquires(lock)
769 {
770 	spin_lock_irqsave(lock, *smp_flags);
771 }
772 
773 
unlock_adapter_irq(spinlock_t * lock,unsigned long * smp_flags)774 static void unlock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
775 	__releases(lock)
776 {
777 	spin_unlock_irqrestore(lock, *smp_flags);
778 }
779 
780 EXPORT_SYMBOL(register_wan_device);
781 EXPORT_SYMBOL(unregister_wan_device);
782 
783 MODULE_LICENSE("GPL");
784 
785 /*
786  *	End
787  */
788