net: sock_def_readable() and friends RCU conversion
[linux-2.6.git] / net / atm / br2684.c
1 /*
2  * Ethernet netdevice using ATM AAL5 as underlying carrier
3  * (RFC1483 obsoleted by RFC2684) for Linux
4  *
5  * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
6  *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
7  */
8
9 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
10
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/netdevice.h>
16 #include <linux/skbuff.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/ip.h>
20 #include <linux/uaccess.h>
21 #include <linux/slab.h>
22 #include <net/arp.h>
23 #include <linux/atm.h>
24 #include <linux/atmdev.h>
25 #include <linux/capability.h>
26 #include <linux/seq_file.h>
27
28 #include <linux/atmbr2684.h>
29
30 #include "common.h"
31
32 static void skb_debug(const struct sk_buff *skb)
33 {
34 #ifdef SKB_DEBUG
35 #define NUM2PRINT 50
36         print_hex_dump(KERN_DEBUG, "br2684: skb: ", DUMP_OFFSET,
37                        16, 1, skb->data, min(NUM2PRINT, skb->len), true);
38 #endif
39 }
40
41 #define BR2684_ETHERTYPE_LEN    2
42 #define BR2684_PAD_LEN          2
43
44 #define LLC             0xaa, 0xaa, 0x03
45 #define SNAP_BRIDGED    0x00, 0x80, 0xc2
46 #define SNAP_ROUTED     0x00, 0x00, 0x00
47 #define PID_ETHERNET    0x00, 0x07
48 #define ETHERTYPE_IPV4  0x08, 0x00
49 #define ETHERTYPE_IPV6  0x86, 0xdd
50 #define PAD_BRIDGED     0x00, 0x00
51
52 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
53 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
54 static const unsigned char llc_oui_pid_pad[] =
55                         { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
56 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
57 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
58
59 enum br2684_encaps {
60         e_vc = BR2684_ENCAPS_VC,
61         e_llc = BR2684_ENCAPS_LLC,
62 };
63
64 struct br2684_vcc {
65         struct atm_vcc *atmvcc;
66         struct net_device *device;
67         /* keep old push, pop functions for chaining */
68         void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
69         void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
70         enum br2684_encaps encaps;
71         struct list_head brvccs;
72 #ifdef CONFIG_ATM_BR2684_IPFILTER
73         struct br2684_filter filter;
74 #endif /* CONFIG_ATM_BR2684_IPFILTER */
75         unsigned copies_needed, copies_failed;
76 };
77
78 struct br2684_dev {
79         struct net_device *net_dev;
80         struct list_head br2684_devs;
81         int number;
82         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
83         int mac_was_set;
84         enum br2684_payload payload;
85 };
86
87 /*
88  * This lock should be held for writing any time the list of devices or
89  * their attached vcc's could be altered.  It should be held for reading
90  * any time these are being queried.  Note that we sometimes need to
91  * do read-locking under interrupt context, so write locking must block
92  * the current CPU's interrupts
93  */
94 static DEFINE_RWLOCK(devs_lock);
95
96 static LIST_HEAD(br2684_devs);
97
98 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
99 {
100         return (struct br2684_dev *)netdev_priv(net_dev);
101 }
102
103 static inline struct net_device *list_entry_brdev(const struct list_head *le)
104 {
105         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
106 }
107
108 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
109 {
110         return (struct br2684_vcc *)(atmvcc->user_back);
111 }
112
113 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
114 {
115         return list_entry(le, struct br2684_vcc, brvccs);
116 }
117
118 /* Caller should hold read_lock(&devs_lock) */
119 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
120 {
121         struct list_head *lh;
122         struct net_device *net_dev;
123         switch (s->method) {
124         case BR2684_FIND_BYNUM:
125                 list_for_each(lh, &br2684_devs) {
126                         net_dev = list_entry_brdev(lh);
127                         if (BRPRIV(net_dev)->number == s->spec.devnum)
128                                 return net_dev;
129                 }
130                 break;
131         case BR2684_FIND_BYIFNAME:
132                 list_for_each(lh, &br2684_devs) {
133                         net_dev = list_entry_brdev(lh);
134                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
135                                 return net_dev;
136                 }
137                 break;
138         }
139         return NULL;
140 }
141
142 /* chained vcc->pop function.  Check if we should wake the netif_queue */
143 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
144 {
145         struct br2684_vcc *brvcc = BR2684_VCC(vcc);
146         struct net_device *net_dev = skb->dev;
147
148         pr_debug("(vcc %p ; net_dev %p )\n", vcc, net_dev);
149         brvcc->old_pop(vcc, skb);
150
151         if (!net_dev)
152                 return;
153
154         if (atm_may_send(vcc, 0))
155                 netif_wake_queue(net_dev);
156
157 }
158 /*
159  * Send a packet out a particular vcc.  Not to useful right now, but paves
160  * the way for multiple vcc's per itf.  Returns true if we can send,
161  * otherwise false
162  */
163 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
164                            struct br2684_vcc *brvcc)
165 {
166         struct br2684_dev *brdev = BRPRIV(dev);
167         struct atm_vcc *atmvcc;
168         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
169
170         if (skb_headroom(skb) < minheadroom) {
171                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
172                 brvcc->copies_needed++;
173                 dev_kfree_skb(skb);
174                 if (skb2 == NULL) {
175                         brvcc->copies_failed++;
176                         return 0;
177                 }
178                 skb = skb2;
179         }
180
181         if (brvcc->encaps == e_llc) {
182                 if (brdev->payload == p_bridged) {
183                         skb_push(skb, sizeof(llc_oui_pid_pad));
184                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
185                                                 sizeof(llc_oui_pid_pad));
186                 } else if (brdev->payload == p_routed) {
187                         unsigned short prot = ntohs(skb->protocol);
188
189                         skb_push(skb, sizeof(llc_oui_ipv4));
190                         switch (prot) {
191                         case ETH_P_IP:
192                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
193                                                         sizeof(llc_oui_ipv4));
194                                 break;
195                         case ETH_P_IPV6:
196                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
197                                                         sizeof(llc_oui_ipv6));
198                                 break;
199                         default:
200                                 dev_kfree_skb(skb);
201                                 return 0;
202                         }
203                 }
204         } else { /* e_vc */
205                 if (brdev->payload == p_bridged) {
206                         skb_push(skb, 2);
207                         memset(skb->data, 0, 2);
208                 } else { /* p_routed */
209                         skb_pull(skb, ETH_HLEN);
210                 }
211         }
212         skb_debug(skb);
213
214         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
215         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
216         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
217         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
218         dev->stats.tx_packets++;
219         dev->stats.tx_bytes += skb->len;
220         atmvcc->send(atmvcc, skb);
221
222         if (!atm_may_send(atmvcc, 0)) {
223                 netif_stop_queue(brvcc->device);
224                 /*check for race with br2684_pop*/
225                 if (atm_may_send(atmvcc, 0))
226                         netif_start_queue(brvcc->device);
227         }
228
229         return 1;
230 }
231
232 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
233                                                    const struct br2684_dev *brdev)
234 {
235         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
236 }
237
238 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
239                                      struct net_device *dev)
240 {
241         struct br2684_dev *brdev = BRPRIV(dev);
242         struct br2684_vcc *brvcc;
243
244         pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
245         read_lock(&devs_lock);
246         brvcc = pick_outgoing_vcc(skb, brdev);
247         if (brvcc == NULL) {
248                 pr_debug("no vcc attached to dev %s\n", dev->name);
249                 dev->stats.tx_errors++;
250                 dev->stats.tx_carrier_errors++;
251                 /* netif_stop_queue(dev); */
252                 dev_kfree_skb(skb);
253                 read_unlock(&devs_lock);
254                 return NETDEV_TX_OK;
255         }
256         if (!br2684_xmit_vcc(skb, dev, brvcc)) {
257                 /*
258                  * We should probably use netif_*_queue() here, but that
259                  * involves added complication.  We need to walk before
260                  * we can run.
261                  *
262                  * Don't free here! this pointer might be no longer valid!
263                  */
264                 dev->stats.tx_errors++;
265                 dev->stats.tx_fifo_errors++;
266         }
267         read_unlock(&devs_lock);
268         return NETDEV_TX_OK;
269 }
270
271 /*
272  * We remember when the MAC gets set, so we don't override it later with
273  * the ESI of the ATM card of the first VC
274  */
275 static int br2684_mac_addr(struct net_device *dev, void *p)
276 {
277         int err = eth_mac_addr(dev, p);
278         if (!err)
279                 BRPRIV(dev)->mac_was_set = 1;
280         return err;
281 }
282
283 #ifdef CONFIG_ATM_BR2684_IPFILTER
284 /* this IOCTL is experimental. */
285 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
286 {
287         struct br2684_vcc *brvcc;
288         struct br2684_filter_set fs;
289
290         if (copy_from_user(&fs, arg, sizeof fs))
291                 return -EFAULT;
292         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
293                 /*
294                  * This is really a per-vcc thing, but we can also search
295                  * by device.
296                  */
297                 struct br2684_dev *brdev;
298                 read_lock(&devs_lock);
299                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
300                 if (brdev == NULL || list_empty(&brdev->brvccs) ||
301                     brdev->brvccs.next != brdev->brvccs.prev)   /* >1 VCC */
302                         brvcc = NULL;
303                 else
304                         brvcc = list_entry_brvcc(brdev->brvccs.next);
305                 read_unlock(&devs_lock);
306                 if (brvcc == NULL)
307                         return -ESRCH;
308         } else
309                 brvcc = BR2684_VCC(atmvcc);
310         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
311         return 0;
312 }
313
314 /* Returns 1 if packet should be dropped */
315 static inline int
316 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
317 {
318         if (brvcc->filter.netmask == 0)
319                 return 0;       /* no filter in place */
320         if (type == htons(ETH_P_IP) &&
321             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
322              netmask) == brvcc->filter.prefix)
323                 return 0;
324         if (type == htons(ETH_P_ARP))
325                 return 0;
326         /*
327          * TODO: we should probably filter ARPs too.. don't want to have
328          * them returning values that don't make sense, or is that ok?
329          */
330         return 1;               /* drop */
331 }
332 #endif /* CONFIG_ATM_BR2684_IPFILTER */
333
334 static void br2684_close_vcc(struct br2684_vcc *brvcc)
335 {
336         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
337         write_lock_irq(&devs_lock);
338         list_del(&brvcc->brvccs);
339         write_unlock_irq(&devs_lock);
340         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
341         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
342         kfree(brvcc);
343         module_put(THIS_MODULE);
344 }
345
346 /* when AAL5 PDU comes in: */
347 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
348 {
349         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
350         struct net_device *net_dev = brvcc->device;
351         struct br2684_dev *brdev = BRPRIV(net_dev);
352
353         pr_debug("\n");
354
355         if (unlikely(skb == NULL)) {
356                 /* skb==NULL means VCC is being destroyed */
357                 br2684_close_vcc(brvcc);
358                 if (list_empty(&brdev->brvccs)) {
359                         write_lock_irq(&devs_lock);
360                         list_del(&brdev->br2684_devs);
361                         write_unlock_irq(&devs_lock);
362                         unregister_netdev(net_dev);
363                         free_netdev(net_dev);
364                 }
365                 return;
366         }
367
368         skb_debug(skb);
369         atm_return(atmvcc, skb->truesize);
370         pr_debug("skb from brdev %p\n", brdev);
371         if (brvcc->encaps == e_llc) {
372
373                 if (skb->len > 7 && skb->data[7] == 0x01)
374                         __skb_trim(skb, skb->len - 4);
375
376                 /* accept packets that have "ipv[46]" in the snap header */
377                 if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
378                     (memcmp(skb->data, llc_oui_ipv4,
379                             sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
380                         if (memcmp(skb->data + 6, ethertype_ipv6,
381                                    sizeof(ethertype_ipv6)) == 0)
382                                 skb->protocol = htons(ETH_P_IPV6);
383                         else if (memcmp(skb->data + 6, ethertype_ipv4,
384                                         sizeof(ethertype_ipv4)) == 0)
385                                 skb->protocol = htons(ETH_P_IP);
386                         else
387                                 goto error;
388                         skb_pull(skb, sizeof(llc_oui_ipv4));
389                         skb_reset_network_header(skb);
390                         skb->pkt_type = PACKET_HOST;
391                 /*
392                  * Let us waste some time for checking the encapsulation.
393                  * Note, that only 7 char is checked so frames with a valid FCS
394                  * are also accepted (but FCS is not checked of course).
395                  */
396                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
397                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
398                         skb_pull(skb, sizeof(llc_oui_pid_pad));
399                         skb->protocol = eth_type_trans(skb, net_dev);
400                 } else
401                         goto error;
402
403         } else { /* e_vc */
404                 if (brdev->payload == p_routed) {
405                         struct iphdr *iph;
406
407                         skb_reset_network_header(skb);
408                         iph = ip_hdr(skb);
409                         if (iph->version == 4)
410                                 skb->protocol = htons(ETH_P_IP);
411                         else if (iph->version == 6)
412                                 skb->protocol = htons(ETH_P_IPV6);
413                         else
414                                 goto error;
415                         skb->pkt_type = PACKET_HOST;
416                 } else { /* p_bridged */
417                         /* first 2 chars should be 0 */
418                         if (*((u16 *) (skb->data)) != 0)
419                                 goto error;
420                         skb_pull(skb, BR2684_PAD_LEN);
421                         skb->protocol = eth_type_trans(skb, net_dev);
422                 }
423         }
424
425 #ifdef CONFIG_ATM_BR2684_IPFILTER
426         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
427                 goto dropped;
428 #endif /* CONFIG_ATM_BR2684_IPFILTER */
429         skb->dev = net_dev;
430         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
431         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
432         skb_debug(skb);
433         /* sigh, interface is down? */
434         if (unlikely(!(net_dev->flags & IFF_UP)))
435                 goto dropped;
436         net_dev->stats.rx_packets++;
437         net_dev->stats.rx_bytes += skb->len;
438         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
439         netif_rx(skb);
440         return;
441
442 dropped:
443         net_dev->stats.rx_dropped++;
444         goto free_skb;
445 error:
446         net_dev->stats.rx_errors++;
447 free_skb:
448         dev_kfree_skb(skb);
449         return;
450 }
451
452 /*
453  * Assign a vcc to a dev
454  * Note: we do not have explicit unassign, but look at _push()
455  */
456 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
457 {
458         struct sk_buff_head queue;
459         int err;
460         struct br2684_vcc *brvcc;
461         struct sk_buff *skb, *tmp;
462         struct sk_buff_head *rq;
463         struct br2684_dev *brdev;
464         struct net_device *net_dev;
465         struct atm_backend_br2684 be;
466         unsigned long flags;
467
468         if (copy_from_user(&be, arg, sizeof be))
469                 return -EFAULT;
470         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
471         if (!brvcc)
472                 return -ENOMEM;
473         write_lock_irq(&devs_lock);
474         net_dev = br2684_find_dev(&be.ifspec);
475         if (net_dev == NULL) {
476                 pr_err("tried to attach to non-existant device\n");
477                 err = -ENXIO;
478                 goto error;
479         }
480         brdev = BRPRIV(net_dev);
481         if (atmvcc->push == NULL) {
482                 err = -EBADFD;
483                 goto error;
484         }
485         if (!list_empty(&brdev->brvccs)) {
486                 /* Only 1 VCC/dev right now */
487                 err = -EEXIST;
488                 goto error;
489         }
490         if (be.fcs_in != BR2684_FCSIN_NO ||
491             be.fcs_out != BR2684_FCSOUT_NO ||
492             be.fcs_auto || be.has_vpiid || be.send_padding ||
493             (be.encaps != BR2684_ENCAPS_VC &&
494              be.encaps != BR2684_ENCAPS_LLC) ||
495             be.min_size != 0) {
496                 err = -EINVAL;
497                 goto error;
498         }
499         pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
500         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
501                 unsigned char *esi = atmvcc->dev->esi;
502                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
503                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
504                 else
505                         net_dev->dev_addr[2] = 1;
506         }
507         list_add(&brvcc->brvccs, &brdev->brvccs);
508         write_unlock_irq(&devs_lock);
509         brvcc->device = net_dev;
510         brvcc->atmvcc = atmvcc;
511         atmvcc->user_back = brvcc;
512         brvcc->encaps = (enum br2684_encaps)be.encaps;
513         brvcc->old_push = atmvcc->push;
514         brvcc->old_pop = atmvcc->pop;
515         barrier();
516         atmvcc->push = br2684_push;
517         atmvcc->pop = br2684_pop;
518
519         __skb_queue_head_init(&queue);
520         rq = &sk_atm(atmvcc)->sk_receive_queue;
521
522         spin_lock_irqsave(&rq->lock, flags);
523         skb_queue_splice_init(rq, &queue);
524         spin_unlock_irqrestore(&rq->lock, flags);
525
526         skb_queue_walk_safe(&queue, skb, tmp) {
527                 struct net_device *dev = skb->dev;
528
529                 dev->stats.rx_bytes -= skb->len;
530                 dev->stats.rx_packets--;
531
532                 br2684_push(atmvcc, skb);
533         }
534         __module_get(THIS_MODULE);
535         return 0;
536
537 error:
538         write_unlock_irq(&devs_lock);
539         kfree(brvcc);
540         return err;
541 }
542
543 static const struct net_device_ops br2684_netdev_ops = {
544         .ndo_start_xmit         = br2684_start_xmit,
545         .ndo_set_mac_address    = br2684_mac_addr,
546         .ndo_change_mtu         = eth_change_mtu,
547         .ndo_validate_addr      = eth_validate_addr,
548 };
549
550 static const struct net_device_ops br2684_netdev_ops_routed = {
551         .ndo_start_xmit         = br2684_start_xmit,
552         .ndo_set_mac_address    = br2684_mac_addr,
553         .ndo_change_mtu         = eth_change_mtu
554 };
555
556 static void br2684_setup(struct net_device *netdev)
557 {
558         struct br2684_dev *brdev = BRPRIV(netdev);
559
560         ether_setup(netdev);
561         brdev->net_dev = netdev;
562
563         netdev->netdev_ops = &br2684_netdev_ops;
564
565         INIT_LIST_HEAD(&brdev->brvccs);
566 }
567
568 static void br2684_setup_routed(struct net_device *netdev)
569 {
570         struct br2684_dev *brdev = BRPRIV(netdev);
571
572         brdev->net_dev = netdev;
573         netdev->hard_header_len = 0;
574         netdev->netdev_ops = &br2684_netdev_ops_routed;
575         netdev->addr_len = 0;
576         netdev->mtu = 1500;
577         netdev->type = ARPHRD_PPP;
578         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
579         netdev->tx_queue_len = 100;
580         INIT_LIST_HEAD(&brdev->brvccs);
581 }
582
583 static int br2684_create(void __user *arg)
584 {
585         int err;
586         struct net_device *netdev;
587         struct br2684_dev *brdev;
588         struct atm_newif_br2684 ni;
589         enum br2684_payload payload;
590
591         pr_debug("\n");
592
593         if (copy_from_user(&ni, arg, sizeof ni))
594                 return -EFAULT;
595
596         if (ni.media & BR2684_FLAG_ROUTED)
597                 payload = p_routed;
598         else
599                 payload = p_bridged;
600         ni.media &= 0xffff;     /* strip flags */
601
602         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
603                 return -EINVAL;
604
605         netdev = alloc_netdev(sizeof(struct br2684_dev),
606                               ni.ifname[0] ? ni.ifname : "nas%d",
607                               (payload == p_routed) ?
608                               br2684_setup_routed : br2684_setup);
609         if (!netdev)
610                 return -ENOMEM;
611
612         brdev = BRPRIV(netdev);
613
614         pr_debug("registered netdev %s\n", netdev->name);
615         /* open, stop, do_ioctl ? */
616         err = register_netdev(netdev);
617         if (err < 0) {
618                 pr_err("register_netdev failed\n");
619                 free_netdev(netdev);
620                 return err;
621         }
622
623         write_lock_irq(&devs_lock);
624         brdev->payload = payload;
625         brdev->number = list_empty(&br2684_devs) ? 1 :
626             BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
627         list_add_tail(&brdev->br2684_devs, &br2684_devs);
628         write_unlock_irq(&devs_lock);
629         return 0;
630 }
631
632 /*
633  * This handles ioctls actually performed on our vcc - we must return
634  * -ENOIOCTLCMD for any unrecognized ioctl
635  */
636 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
637                         unsigned long arg)
638 {
639         struct atm_vcc *atmvcc = ATM_SD(sock);
640         void __user *argp = (void __user *)arg;
641         atm_backend_t b;
642
643         int err;
644         switch (cmd) {
645         case ATM_SETBACKEND:
646         case ATM_NEWBACKENDIF:
647                 err = get_user(b, (atm_backend_t __user *) argp);
648                 if (err)
649                         return -EFAULT;
650                 if (b != ATM_BACKEND_BR2684)
651                         return -ENOIOCTLCMD;
652                 if (!capable(CAP_NET_ADMIN))
653                         return -EPERM;
654                 if (cmd == ATM_SETBACKEND)
655                         return br2684_regvcc(atmvcc, argp);
656                 else
657                         return br2684_create(argp);
658 #ifdef CONFIG_ATM_BR2684_IPFILTER
659         case BR2684_SETFILT:
660                 if (atmvcc->push != br2684_push)
661                         return -ENOIOCTLCMD;
662                 if (!capable(CAP_NET_ADMIN))
663                         return -EPERM;
664                 err = br2684_setfilt(atmvcc, argp);
665
666                 return err;
667 #endif /* CONFIG_ATM_BR2684_IPFILTER */
668         }
669         return -ENOIOCTLCMD;
670 }
671
672 static struct atm_ioctl br2684_ioctl_ops = {
673         .owner = THIS_MODULE,
674         .ioctl = br2684_ioctl,
675 };
676
677 #ifdef CONFIG_PROC_FS
678 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
679         __acquires(devs_lock)
680 {
681         read_lock(&devs_lock);
682         return seq_list_start(&br2684_devs, *pos);
683 }
684
685 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
686 {
687         return seq_list_next(v, &br2684_devs, pos);
688 }
689
690 static void br2684_seq_stop(struct seq_file *seq, void *v)
691         __releases(devs_lock)
692 {
693         read_unlock(&devs_lock);
694 }
695
696 static int br2684_seq_show(struct seq_file *seq, void *v)
697 {
698         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
699                                                     br2684_devs);
700         const struct net_device *net_dev = brdev->net_dev;
701         const struct br2684_vcc *brvcc;
702
703         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
704                    net_dev->name,
705                    brdev->number,
706                    net_dev->dev_addr,
707                    brdev->mac_was_set ? "set" : "auto");
708
709         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
710                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
711                            ", failed copies %u/%u"
712                            "\n", brvcc->atmvcc->dev->number,
713                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
714                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
715                            (brdev->payload == p_bridged) ? "bridged" : "routed",
716                            brvcc->copies_failed, brvcc->copies_needed);
717 #ifdef CONFIG_ATM_BR2684_IPFILTER
718 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
719 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
720                 if (brvcc->filter.netmask != 0)
721                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
722                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
723 #undef bs
724 #undef b1
725 #endif /* CONFIG_ATM_BR2684_IPFILTER */
726         }
727         return 0;
728 }
729
730 static const struct seq_operations br2684_seq_ops = {
731         .start = br2684_seq_start,
732         .next = br2684_seq_next,
733         .stop = br2684_seq_stop,
734         .show = br2684_seq_show,
735 };
736
737 static int br2684_proc_open(struct inode *inode, struct file *file)
738 {
739         return seq_open(file, &br2684_seq_ops);
740 }
741
742 static const struct file_operations br2684_proc_ops = {
743         .owner = THIS_MODULE,
744         .open = br2684_proc_open,
745         .read = seq_read,
746         .llseek = seq_lseek,
747         .release = seq_release,
748 };
749
750 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
751 #endif /* CONFIG_PROC_FS */
752
753 static int __init br2684_init(void)
754 {
755 #ifdef CONFIG_PROC_FS
756         struct proc_dir_entry *p;
757         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
758         if (p == NULL)
759                 return -ENOMEM;
760 #endif
761         register_atm_ioctl(&br2684_ioctl_ops);
762         return 0;
763 }
764
765 static void __exit br2684_exit(void)
766 {
767         struct net_device *net_dev;
768         struct br2684_dev *brdev;
769         struct br2684_vcc *brvcc;
770         deregister_atm_ioctl(&br2684_ioctl_ops);
771
772 #ifdef CONFIG_PROC_FS
773         remove_proc_entry("br2684", atm_proc_root);
774 #endif
775
776         while (!list_empty(&br2684_devs)) {
777                 net_dev = list_entry_brdev(br2684_devs.next);
778                 brdev = BRPRIV(net_dev);
779                 while (!list_empty(&brdev->brvccs)) {
780                         brvcc = list_entry_brvcc(brdev->brvccs.next);
781                         br2684_close_vcc(brvcc);
782                 }
783
784                 list_del(&brdev->br2684_devs);
785                 unregister_netdev(net_dev);
786                 free_netdev(net_dev);
787         }
788 }
789
790 module_init(br2684_init);
791 module_exit(br2684_exit);
792
793 MODULE_AUTHOR("Marcell GAL");
794 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
795 MODULE_LICENSE("GPL");