net: wireless: sd8797: change wlan interface to wlan0
[linux-2.6.git] / net / wanrouter / wanmain.c
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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  */