Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux...
[platform/adaptation/renesas_rcar/renesas_kernel.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 pad[] = { PAD_BRIDGED };
57 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
58 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
59
60 enum br2684_encaps {
61         e_vc = BR2684_ENCAPS_VC,
62         e_llc = BR2684_ENCAPS_LLC,
63 };
64
65 struct br2684_vcc {
66         struct atm_vcc *atmvcc;
67         struct net_device *device;
68         /* keep old push, pop functions for chaining */
69         void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
70         void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
71         void (*old_release_cb)(struct atm_vcc *vcc);
72         struct module *old_owner;
73         enum br2684_encaps encaps;
74         struct list_head brvccs;
75 #ifdef CONFIG_ATM_BR2684_IPFILTER
76         struct br2684_filter filter;
77 #endif /* CONFIG_ATM_BR2684_IPFILTER */
78         unsigned int copies_needed, copies_failed;
79         atomic_t qspace;
80 };
81
82 struct br2684_dev {
83         struct net_device *net_dev;
84         struct list_head br2684_devs;
85         int number;
86         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
87         int mac_was_set;
88         enum br2684_payload payload;
89 };
90
91 /*
92  * This lock should be held for writing any time the list of devices or
93  * their attached vcc's could be altered.  It should be held for reading
94  * any time these are being queried.  Note that we sometimes need to
95  * do read-locking under interrupt context, so write locking must block
96  * the current CPU's interrupts
97  */
98 static DEFINE_RWLOCK(devs_lock);
99
100 static LIST_HEAD(br2684_devs);
101
102 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
103 {
104         return netdev_priv(net_dev);
105 }
106
107 static inline struct net_device *list_entry_brdev(const struct list_head *le)
108 {
109         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
110 }
111
112 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
113 {
114         return (struct br2684_vcc *)(atmvcc->user_back);
115 }
116
117 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
118 {
119         return list_entry(le, struct br2684_vcc, brvccs);
120 }
121
122 /* Caller should hold read_lock(&devs_lock) */
123 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
124 {
125         struct list_head *lh;
126         struct net_device *net_dev;
127         switch (s->method) {
128         case BR2684_FIND_BYNUM:
129                 list_for_each(lh, &br2684_devs) {
130                         net_dev = list_entry_brdev(lh);
131                         if (BRPRIV(net_dev)->number == s->spec.devnum)
132                                 return net_dev;
133                 }
134                 break;
135         case BR2684_FIND_BYIFNAME:
136                 list_for_each(lh, &br2684_devs) {
137                         net_dev = list_entry_brdev(lh);
138                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
139                                 return net_dev;
140                 }
141                 break;
142         }
143         return NULL;
144 }
145
146 static int atm_dev_event(struct notifier_block *this, unsigned long event,
147                  void *arg)
148 {
149         struct atm_dev *atm_dev = arg;
150         struct list_head *lh;
151         struct net_device *net_dev;
152         struct br2684_vcc *brvcc;
153         struct atm_vcc *atm_vcc;
154         unsigned long flags;
155
156         pr_debug("event=%ld dev=%p\n", event, atm_dev);
157
158         read_lock_irqsave(&devs_lock, flags);
159         list_for_each(lh, &br2684_devs) {
160                 net_dev = list_entry_brdev(lh);
161
162                 list_for_each_entry(brvcc, &BRPRIV(net_dev)->brvccs, brvccs) {
163                         atm_vcc = brvcc->atmvcc;
164                         if (atm_vcc && brvcc->atmvcc->dev == atm_dev) {
165
166                                 if (atm_vcc->dev->signal == ATM_PHY_SIG_LOST)
167                                         netif_carrier_off(net_dev);
168                                 else
169                                         netif_carrier_on(net_dev);
170
171                         }
172                 }
173         }
174         read_unlock_irqrestore(&devs_lock, flags);
175
176         return NOTIFY_DONE;
177 }
178
179 static struct notifier_block atm_dev_notifier = {
180         .notifier_call = atm_dev_event,
181 };
182
183 /* chained vcc->pop function.  Check if we should wake the netif_queue */
184 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
185 {
186         struct br2684_vcc *brvcc = BR2684_VCC(vcc);
187
188         pr_debug("(vcc %p ; net_dev %p )\n", vcc, brvcc->device);
189         brvcc->old_pop(vcc, skb);
190
191         /* If the queue space just went up from zero, wake */
192         if (atomic_inc_return(&brvcc->qspace) == 1)
193                 netif_wake_queue(brvcc->device);
194 }
195
196 /*
197  * Send a packet out a particular vcc.  Not to useful right now, but paves
198  * the way for multiple vcc's per itf.  Returns true if we can send,
199  * otherwise false
200  */
201 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
202                            struct br2684_vcc *brvcc)
203 {
204         struct br2684_dev *brdev = BRPRIV(dev);
205         struct atm_vcc *atmvcc;
206         int minheadroom = (brvcc->encaps == e_llc) ?
207                 ((brdev->payload == p_bridged) ?
208                         sizeof(llc_oui_pid_pad) : sizeof(llc_oui_ipv4)) :
209                 ((brdev->payload == p_bridged) ? BR2684_PAD_LEN : 0);
210
211         if (skb_headroom(skb) < minheadroom) {
212                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
213                 brvcc->copies_needed++;
214                 dev_kfree_skb(skb);
215                 if (skb2 == NULL) {
216                         brvcc->copies_failed++;
217                         return 0;
218                 }
219                 skb = skb2;
220         }
221
222         if (brvcc->encaps == e_llc) {
223                 if (brdev->payload == p_bridged) {
224                         skb_push(skb, sizeof(llc_oui_pid_pad));
225                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
226                                                 sizeof(llc_oui_pid_pad));
227                 } else if (brdev->payload == p_routed) {
228                         unsigned short prot = ntohs(skb->protocol);
229
230                         skb_push(skb, sizeof(llc_oui_ipv4));
231                         switch (prot) {
232                         case ETH_P_IP:
233                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
234                                                         sizeof(llc_oui_ipv4));
235                                 break;
236                         case ETH_P_IPV6:
237                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
238                                                         sizeof(llc_oui_ipv6));
239                                 break;
240                         default:
241                                 dev_kfree_skb(skb);
242                                 return 0;
243                         }
244                 }
245         } else { /* e_vc */
246                 if (brdev->payload == p_bridged) {
247                         skb_push(skb, 2);
248                         memset(skb->data, 0, 2);
249                 }
250         }
251         skb_debug(skb);
252
253         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
254         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
255         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
256         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
257         dev->stats.tx_packets++;
258         dev->stats.tx_bytes += skb->len;
259
260         if (atomic_dec_return(&brvcc->qspace) < 1) {
261                 /* No more please! */
262                 netif_stop_queue(brvcc->device);
263                 /* We might have raced with br2684_pop() */
264                 if (unlikely(atomic_read(&brvcc->qspace) > 0))
265                         netif_wake_queue(brvcc->device);
266         }
267
268         /* If this fails immediately, the skb will be freed and br2684_pop()
269            will wake the queue if appropriate. Just return an error so that
270            the stats are updated correctly */
271         return !atmvcc->send(atmvcc, skb);
272 }
273
274 static void br2684_release_cb(struct atm_vcc *atmvcc)
275 {
276         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
277
278         if (atomic_read(&brvcc->qspace) > 0)
279                 netif_wake_queue(brvcc->device);
280
281         if (brvcc->old_release_cb)
282                 brvcc->old_release_cb(atmvcc);
283 }
284
285 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
286                                                    const struct br2684_dev *brdev)
287 {
288         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
289 }
290
291 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
292                                      struct net_device *dev)
293 {
294         struct br2684_dev *brdev = BRPRIV(dev);
295         struct br2684_vcc *brvcc;
296         struct atm_vcc *atmvcc;
297         netdev_tx_t ret = NETDEV_TX_OK;
298
299         pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
300         read_lock(&devs_lock);
301         brvcc = pick_outgoing_vcc(skb, brdev);
302         if (brvcc == NULL) {
303                 pr_debug("no vcc attached to dev %s\n", dev->name);
304                 dev->stats.tx_errors++;
305                 dev->stats.tx_carrier_errors++;
306                 /* netif_stop_queue(dev); */
307                 dev_kfree_skb(skb);
308                 goto out_devs;
309         }
310         atmvcc = brvcc->atmvcc;
311
312         bh_lock_sock(sk_atm(atmvcc));
313
314         if (test_bit(ATM_VF_RELEASED, &atmvcc->flags) ||
315             test_bit(ATM_VF_CLOSE, &atmvcc->flags) ||
316             !test_bit(ATM_VF_READY, &atmvcc->flags)) {
317                 dev->stats.tx_dropped++;
318                 dev_kfree_skb(skb);
319                 goto out;
320         }
321
322         if (sock_owned_by_user(sk_atm(atmvcc))) {
323                 netif_stop_queue(brvcc->device);
324                 ret = NETDEV_TX_BUSY;
325                 goto out;
326         }
327
328         if (!br2684_xmit_vcc(skb, dev, brvcc)) {
329                 /*
330                  * We should probably use netif_*_queue() here, but that
331                  * involves added complication.  We need to walk before
332                  * we can run.
333                  *
334                  * Don't free here! this pointer might be no longer valid!
335                  */
336                 dev->stats.tx_errors++;
337                 dev->stats.tx_fifo_errors++;
338         }
339  out:
340         bh_unlock_sock(sk_atm(atmvcc));
341  out_devs:
342         read_unlock(&devs_lock);
343         return ret;
344 }
345
346 /*
347  * We remember when the MAC gets set, so we don't override it later with
348  * the ESI of the ATM card of the first VC
349  */
350 static int br2684_mac_addr(struct net_device *dev, void *p)
351 {
352         int err = eth_mac_addr(dev, p);
353         if (!err)
354                 BRPRIV(dev)->mac_was_set = 1;
355         return err;
356 }
357
358 #ifdef CONFIG_ATM_BR2684_IPFILTER
359 /* this IOCTL is experimental. */
360 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
361 {
362         struct br2684_vcc *brvcc;
363         struct br2684_filter_set fs;
364
365         if (copy_from_user(&fs, arg, sizeof fs))
366                 return -EFAULT;
367         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
368                 /*
369                  * This is really a per-vcc thing, but we can also search
370                  * by device.
371                  */
372                 struct br2684_dev *brdev;
373                 read_lock(&devs_lock);
374                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
375                 if (brdev == NULL || list_empty(&brdev->brvccs) ||
376                     brdev->brvccs.next != brdev->brvccs.prev)   /* >1 VCC */
377                         brvcc = NULL;
378                 else
379                         brvcc = list_entry_brvcc(brdev->brvccs.next);
380                 read_unlock(&devs_lock);
381                 if (brvcc == NULL)
382                         return -ESRCH;
383         } else
384                 brvcc = BR2684_VCC(atmvcc);
385         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
386         return 0;
387 }
388
389 /* Returns 1 if packet should be dropped */
390 static inline int
391 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
392 {
393         if (brvcc->filter.netmask == 0)
394                 return 0;       /* no filter in place */
395         if (type == htons(ETH_P_IP) &&
396             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
397              netmask) == brvcc->filter.prefix)
398                 return 0;
399         if (type == htons(ETH_P_ARP))
400                 return 0;
401         /*
402          * TODO: we should probably filter ARPs too.. don't want to have
403          * them returning values that don't make sense, or is that ok?
404          */
405         return 1;               /* drop */
406 }
407 #endif /* CONFIG_ATM_BR2684_IPFILTER */
408
409 static void br2684_close_vcc(struct br2684_vcc *brvcc)
410 {
411         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
412         write_lock_irq(&devs_lock);
413         list_del(&brvcc->brvccs);
414         write_unlock_irq(&devs_lock);
415         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
416         brvcc->atmvcc->release_cb = brvcc->old_release_cb;
417         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
418         module_put(brvcc->old_owner);
419         kfree(brvcc);
420 }
421
422 /* when AAL5 PDU comes in: */
423 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
424 {
425         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
426         struct net_device *net_dev = brvcc->device;
427         struct br2684_dev *brdev = BRPRIV(net_dev);
428
429         pr_debug("\n");
430
431         if (unlikely(skb == NULL)) {
432                 /* skb==NULL means VCC is being destroyed */
433                 br2684_close_vcc(brvcc);
434                 if (list_empty(&brdev->brvccs)) {
435                         write_lock_irq(&devs_lock);
436                         list_del(&brdev->br2684_devs);
437                         write_unlock_irq(&devs_lock);
438                         unregister_netdev(net_dev);
439                         free_netdev(net_dev);
440                 }
441                 return;
442         }
443
444         skb_debug(skb);
445         atm_return(atmvcc, skb->truesize);
446         pr_debug("skb from brdev %p\n", brdev);
447         if (brvcc->encaps == e_llc) {
448
449                 if (skb->len > 7 && skb->data[7] == 0x01)
450                         __skb_trim(skb, skb->len - 4);
451
452                 /* accept packets that have "ipv[46]" in the snap header */
453                 if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
454                     (memcmp(skb->data, llc_oui_ipv4,
455                             sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
456                         if (memcmp(skb->data + 6, ethertype_ipv6,
457                                    sizeof(ethertype_ipv6)) == 0)
458                                 skb->protocol = htons(ETH_P_IPV6);
459                         else if (memcmp(skb->data + 6, ethertype_ipv4,
460                                         sizeof(ethertype_ipv4)) == 0)
461                                 skb->protocol = htons(ETH_P_IP);
462                         else
463                                 goto error;
464                         skb_pull(skb, sizeof(llc_oui_ipv4));
465                         skb_reset_network_header(skb);
466                         skb->pkt_type = PACKET_HOST;
467                 /*
468                  * Let us waste some time for checking the encapsulation.
469                  * Note, that only 7 char is checked so frames with a valid FCS
470                  * are also accepted (but FCS is not checked of course).
471                  */
472                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
473                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
474                         skb_pull(skb, sizeof(llc_oui_pid_pad));
475                         skb->protocol = eth_type_trans(skb, net_dev);
476                 } else
477                         goto error;
478
479         } else { /* e_vc */
480                 if (brdev->payload == p_routed) {
481                         struct iphdr *iph;
482
483                         skb_reset_network_header(skb);
484                         iph = ip_hdr(skb);
485                         if (iph->version == 4)
486                                 skb->protocol = htons(ETH_P_IP);
487                         else if (iph->version == 6)
488                                 skb->protocol = htons(ETH_P_IPV6);
489                         else
490                                 goto error;
491                         skb->pkt_type = PACKET_HOST;
492                 } else { /* p_bridged */
493                         /* first 2 chars should be 0 */
494                         if (memcmp(skb->data, pad, BR2684_PAD_LEN) != 0)
495                                 goto error;
496                         skb_pull(skb, BR2684_PAD_LEN);
497                         skb->protocol = eth_type_trans(skb, net_dev);
498                 }
499         }
500
501 #ifdef CONFIG_ATM_BR2684_IPFILTER
502         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
503                 goto dropped;
504 #endif /* CONFIG_ATM_BR2684_IPFILTER */
505         skb->dev = net_dev;
506         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
507         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
508         skb_debug(skb);
509         /* sigh, interface is down? */
510         if (unlikely(!(net_dev->flags & IFF_UP)))
511                 goto dropped;
512         net_dev->stats.rx_packets++;
513         net_dev->stats.rx_bytes += skb->len;
514         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
515         netif_rx(skb);
516         return;
517
518 dropped:
519         net_dev->stats.rx_dropped++;
520         goto free_skb;
521 error:
522         net_dev->stats.rx_errors++;
523 free_skb:
524         dev_kfree_skb(skb);
525 }
526
527 /*
528  * Assign a vcc to a dev
529  * Note: we do not have explicit unassign, but look at _push()
530  */
531 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
532 {
533         struct br2684_vcc *brvcc;
534         struct br2684_dev *brdev;
535         struct net_device *net_dev;
536         struct atm_backend_br2684 be;
537         int err;
538
539         if (copy_from_user(&be, arg, sizeof be))
540                 return -EFAULT;
541         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
542         if (!brvcc)
543                 return -ENOMEM;
544         /*
545          * Allow two packets in the ATM queue. One actually being sent, and one
546          * for the ATM 'TX done' handler to send. It shouldn't take long to get
547          * the next one from the netdev queue, when we need it. More than that
548          * would be bufferbloat.
549          */
550         atomic_set(&brvcc->qspace, 2);
551         write_lock_irq(&devs_lock);
552         net_dev = br2684_find_dev(&be.ifspec);
553         if (net_dev == NULL) {
554                 pr_err("tried to attach to non-existent device\n");
555                 err = -ENXIO;
556                 goto error;
557         }
558         brdev = BRPRIV(net_dev);
559         if (atmvcc->push == NULL) {
560                 err = -EBADFD;
561                 goto error;
562         }
563         if (!list_empty(&brdev->brvccs)) {
564                 /* Only 1 VCC/dev right now */
565                 err = -EEXIST;
566                 goto error;
567         }
568         if (be.fcs_in != BR2684_FCSIN_NO ||
569             be.fcs_out != BR2684_FCSOUT_NO ||
570             be.fcs_auto || be.has_vpiid || be.send_padding ||
571             (be.encaps != BR2684_ENCAPS_VC &&
572              be.encaps != BR2684_ENCAPS_LLC) ||
573             be.min_size != 0) {
574                 err = -EINVAL;
575                 goto error;
576         }
577         pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
578         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
579                 unsigned char *esi = atmvcc->dev->esi;
580                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
581                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
582                 else
583                         net_dev->dev_addr[2] = 1;
584         }
585         list_add(&brvcc->brvccs, &brdev->brvccs);
586         write_unlock_irq(&devs_lock);
587         brvcc->device = net_dev;
588         brvcc->atmvcc = atmvcc;
589         atmvcc->user_back = brvcc;
590         brvcc->encaps = (enum br2684_encaps)be.encaps;
591         brvcc->old_push = atmvcc->push;
592         brvcc->old_pop = atmvcc->pop;
593         brvcc->old_release_cb = atmvcc->release_cb;
594         brvcc->old_owner = atmvcc->owner;
595         barrier();
596         atmvcc->push = br2684_push;
597         atmvcc->pop = br2684_pop;
598         atmvcc->release_cb = br2684_release_cb;
599         atmvcc->owner = THIS_MODULE;
600
601         /* initialize netdev carrier state */
602         if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
603                 netif_carrier_off(net_dev);
604         else
605                 netif_carrier_on(net_dev);
606
607         __module_get(THIS_MODULE);
608
609         /* re-process everything received between connection setup and
610            backend setup */
611         vcc_process_recv_queue(atmvcc);
612         return 0;
613
614 error:
615         write_unlock_irq(&devs_lock);
616         kfree(brvcc);
617         return err;
618 }
619
620 static const struct net_device_ops br2684_netdev_ops = {
621         .ndo_start_xmit         = br2684_start_xmit,
622         .ndo_set_mac_address    = br2684_mac_addr,
623         .ndo_change_mtu         = eth_change_mtu,
624         .ndo_validate_addr      = eth_validate_addr,
625 };
626
627 static const struct net_device_ops br2684_netdev_ops_routed = {
628         .ndo_start_xmit         = br2684_start_xmit,
629         .ndo_set_mac_address    = br2684_mac_addr,
630         .ndo_change_mtu         = eth_change_mtu
631 };
632
633 static void br2684_setup(struct net_device *netdev)
634 {
635         struct br2684_dev *brdev = BRPRIV(netdev);
636
637         ether_setup(netdev);
638         netdev->hard_header_len += sizeof(llc_oui_pid_pad); /* worst case */
639         brdev->net_dev = netdev;
640
641         netdev->netdev_ops = &br2684_netdev_ops;
642
643         INIT_LIST_HEAD(&brdev->brvccs);
644 }
645
646 static void br2684_setup_routed(struct net_device *netdev)
647 {
648         struct br2684_dev *brdev = BRPRIV(netdev);
649
650         brdev->net_dev = netdev;
651         netdev->hard_header_len = sizeof(llc_oui_ipv4); /* worst case */
652         netdev->netdev_ops = &br2684_netdev_ops_routed;
653         netdev->addr_len = 0;
654         netdev->mtu = 1500;
655         netdev->type = ARPHRD_PPP;
656         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
657         netdev->tx_queue_len = 100;
658         INIT_LIST_HEAD(&brdev->brvccs);
659 }
660
661 static int br2684_create(void __user *arg)
662 {
663         int err;
664         struct net_device *netdev;
665         struct br2684_dev *brdev;
666         struct atm_newif_br2684 ni;
667         enum br2684_payload payload;
668
669         pr_debug("\n");
670
671         if (copy_from_user(&ni, arg, sizeof ni))
672                 return -EFAULT;
673
674         if (ni.media & BR2684_FLAG_ROUTED)
675                 payload = p_routed;
676         else
677                 payload = p_bridged;
678         ni.media &= 0xffff;     /* strip flags */
679
680         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
681                 return -EINVAL;
682
683         netdev = alloc_netdev(sizeof(struct br2684_dev),
684                               ni.ifname[0] ? ni.ifname : "nas%d",
685                               (payload == p_routed) ?
686                               br2684_setup_routed : br2684_setup);
687         if (!netdev)
688                 return -ENOMEM;
689
690         brdev = BRPRIV(netdev);
691
692         pr_debug("registered netdev %s\n", netdev->name);
693         /* open, stop, do_ioctl ? */
694         err = register_netdev(netdev);
695         if (err < 0) {
696                 pr_err("register_netdev failed\n");
697                 free_netdev(netdev);
698                 return err;
699         }
700
701         write_lock_irq(&devs_lock);
702
703         brdev->payload = payload;
704
705         if (list_empty(&br2684_devs)) {
706                 /* 1st br2684 device */
707                 brdev->number = 1;
708         } else
709                 brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
710
711         list_add_tail(&brdev->br2684_devs, &br2684_devs);
712         write_unlock_irq(&devs_lock);
713         return 0;
714 }
715
716 /*
717  * This handles ioctls actually performed on our vcc - we must return
718  * -ENOIOCTLCMD for any unrecognized ioctl
719  */
720 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
721                         unsigned long arg)
722 {
723         struct atm_vcc *atmvcc = ATM_SD(sock);
724         void __user *argp = (void __user *)arg;
725         atm_backend_t b;
726
727         int err;
728         switch (cmd) {
729         case ATM_SETBACKEND:
730         case ATM_NEWBACKENDIF:
731                 err = get_user(b, (atm_backend_t __user *) argp);
732                 if (err)
733                         return -EFAULT;
734                 if (b != ATM_BACKEND_BR2684)
735                         return -ENOIOCTLCMD;
736                 if (!capable(CAP_NET_ADMIN))
737                         return -EPERM;
738                 if (cmd == ATM_SETBACKEND) {
739                         if (sock->state != SS_CONNECTED)
740                                 return -EINVAL;
741                         return br2684_regvcc(atmvcc, argp);
742                 } else {
743                         return br2684_create(argp);
744                 }
745 #ifdef CONFIG_ATM_BR2684_IPFILTER
746         case BR2684_SETFILT:
747                 if (atmvcc->push != br2684_push)
748                         return -ENOIOCTLCMD;
749                 if (!capable(CAP_NET_ADMIN))
750                         return -EPERM;
751                 err = br2684_setfilt(atmvcc, argp);
752
753                 return err;
754 #endif /* CONFIG_ATM_BR2684_IPFILTER */
755         }
756         return -ENOIOCTLCMD;
757 }
758
759 static struct atm_ioctl br2684_ioctl_ops = {
760         .owner = THIS_MODULE,
761         .ioctl = br2684_ioctl,
762 };
763
764 #ifdef CONFIG_PROC_FS
765 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
766         __acquires(devs_lock)
767 {
768         read_lock(&devs_lock);
769         return seq_list_start(&br2684_devs, *pos);
770 }
771
772 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
773 {
774         return seq_list_next(v, &br2684_devs, pos);
775 }
776
777 static void br2684_seq_stop(struct seq_file *seq, void *v)
778         __releases(devs_lock)
779 {
780         read_unlock(&devs_lock);
781 }
782
783 static int br2684_seq_show(struct seq_file *seq, void *v)
784 {
785         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
786                                                     br2684_devs);
787         const struct net_device *net_dev = brdev->net_dev;
788         const struct br2684_vcc *brvcc;
789
790         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
791                    net_dev->name,
792                    brdev->number,
793                    net_dev->dev_addr,
794                    brdev->mac_was_set ? "set" : "auto");
795
796         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
797                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
798                            ", failed copies %u/%u"
799                            "\n", brvcc->atmvcc->dev->number,
800                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
801                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
802                            (brdev->payload == p_bridged) ? "bridged" : "routed",
803                            brvcc->copies_failed, brvcc->copies_needed);
804 #ifdef CONFIG_ATM_BR2684_IPFILTER
805 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
806 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
807                 if (brvcc->filter.netmask != 0)
808                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
809                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
810 #undef bs
811 #undef b1
812 #endif /* CONFIG_ATM_BR2684_IPFILTER */
813         }
814         return 0;
815 }
816
817 static const struct seq_operations br2684_seq_ops = {
818         .start = br2684_seq_start,
819         .next = br2684_seq_next,
820         .stop = br2684_seq_stop,
821         .show = br2684_seq_show,
822 };
823
824 static int br2684_proc_open(struct inode *inode, struct file *file)
825 {
826         return seq_open(file, &br2684_seq_ops);
827 }
828
829 static const struct file_operations br2684_proc_ops = {
830         .owner = THIS_MODULE,
831         .open = br2684_proc_open,
832         .read = seq_read,
833         .llseek = seq_lseek,
834         .release = seq_release,
835 };
836
837 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
838 #endif /* CONFIG_PROC_FS */
839
840 static int __init br2684_init(void)
841 {
842 #ifdef CONFIG_PROC_FS
843         struct proc_dir_entry *p;
844         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
845         if (p == NULL)
846                 return -ENOMEM;
847 #endif
848         register_atm_ioctl(&br2684_ioctl_ops);
849         register_atmdevice_notifier(&atm_dev_notifier);
850         return 0;
851 }
852
853 static void __exit br2684_exit(void)
854 {
855         struct net_device *net_dev;
856         struct br2684_dev *brdev;
857         struct br2684_vcc *brvcc;
858         deregister_atm_ioctl(&br2684_ioctl_ops);
859
860 #ifdef CONFIG_PROC_FS
861         remove_proc_entry("br2684", atm_proc_root);
862 #endif
863
864
865         unregister_atmdevice_notifier(&atm_dev_notifier);
866
867         while (!list_empty(&br2684_devs)) {
868                 net_dev = list_entry_brdev(br2684_devs.next);
869                 brdev = BRPRIV(net_dev);
870                 while (!list_empty(&brdev->brvccs)) {
871                         brvcc = list_entry_brvcc(brdev->brvccs.next);
872                         br2684_close_vcc(brvcc);
873                 }
874
875                 list_del(&brdev->br2684_devs);
876                 unregister_netdev(net_dev);
877                 free_netdev(net_dev);
878         }
879 }
880
881 module_init(br2684_init);
882 module_exit(br2684_exit);
883
884 MODULE_AUTHOR("Marcell GAL");
885 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
886 MODULE_LICENSE("GPL");