GNU Linux-libre 6.8.9-gnu
[releases.git] / drivers / firewire / net.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IPv4 over IEEE 1394, per RFC 2734
4  * IPv6 over IEEE 1394, per RFC 3146
5  *
6  * Copyright (C) 2009 Jay Fenlason <fenlason@redhat.com>
7  *
8  * based on eth1394 by Ben Collins et al
9  */
10
11 #include <linux/bug.h>
12 #include <linux/compiler.h>
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/ethtool.h>
16 #include <linux/firewire.h>
17 #include <linux/firewire-constants.h>
18 #include <linux/highmem.h>
19 #include <linux/in.h>
20 #include <linux/ip.h>
21 #include <linux/jiffies.h>
22 #include <linux/mod_devicetable.h>
23 #include <linux/module.h>
24 #include <linux/moduleparam.h>
25 #include <linux/mutex.h>
26 #include <linux/netdevice.h>
27 #include <linux/skbuff.h>
28 #include <linux/slab.h>
29 #include <linux/spinlock.h>
30
31 #include <asm/unaligned.h>
32 #include <net/arp.h>
33 #include <net/firewire.h>
34
35 /* rx limits */
36 #define FWNET_MAX_FRAGMENTS             30 /* arbitrary, > TX queue depth */
37 #define FWNET_ISO_PAGE_COUNT            (PAGE_SIZE < 16*1024 ? 4 : 2)
38
39 /* tx limits */
40 #define FWNET_MAX_QUEUED_DATAGRAMS      20 /* < 64 = number of tlabels */
41 #define FWNET_MIN_QUEUED_DATAGRAMS      10 /* should keep AT DMA busy enough */
42 #define FWNET_TX_QUEUE_LEN              FWNET_MAX_QUEUED_DATAGRAMS /* ? */
43
44 #define IEEE1394_BROADCAST_CHANNEL      31
45 #define IEEE1394_ALL_NODES              (0xffc0 | 0x003f)
46 #define IEEE1394_MAX_PAYLOAD_S100       512
47 #define FWNET_NO_FIFO_ADDR              (~0ULL)
48
49 #define IANA_SPECIFIER_ID               0x00005eU
50 #define RFC2734_SW_VERSION              0x000001U
51 #define RFC3146_SW_VERSION              0x000002U
52
53 #define IEEE1394_GASP_HDR_SIZE  8
54
55 #define RFC2374_UNFRAG_HDR_SIZE 4
56 #define RFC2374_FRAG_HDR_SIZE   8
57 #define RFC2374_FRAG_OVERHEAD   4
58
59 #define RFC2374_HDR_UNFRAG      0       /* unfragmented         */
60 #define RFC2374_HDR_FIRSTFRAG   1       /* first fragment       */
61 #define RFC2374_HDR_LASTFRAG    2       /* last fragment        */
62 #define RFC2374_HDR_INTFRAG     3       /* interior fragment    */
63
64 static bool fwnet_hwaddr_is_multicast(u8 *ha)
65 {
66         return !!(*ha & 1);
67 }
68
69 /* IPv4 and IPv6 encapsulation header */
70 struct rfc2734_header {
71         u32 w0;
72         u32 w1;
73 };
74
75 #define fwnet_get_hdr_lf(h)             (((h)->w0 & 0xc0000000) >> 30)
76 #define fwnet_get_hdr_ether_type(h)     (((h)->w0 & 0x0000ffff))
77 #define fwnet_get_hdr_dg_size(h)        ((((h)->w0 & 0x0fff0000) >> 16) + 1)
78 #define fwnet_get_hdr_fg_off(h)         (((h)->w0 & 0x00000fff))
79 #define fwnet_get_hdr_dgl(h)            (((h)->w1 & 0xffff0000) >> 16)
80
81 #define fwnet_set_hdr_lf(lf)            ((lf) << 30)
82 #define fwnet_set_hdr_ether_type(et)    (et)
83 #define fwnet_set_hdr_dg_size(dgs)      (((dgs) - 1) << 16)
84 #define fwnet_set_hdr_fg_off(fgo)       (fgo)
85
86 #define fwnet_set_hdr_dgl(dgl)          ((dgl) << 16)
87
88 static inline void fwnet_make_uf_hdr(struct rfc2734_header *hdr,
89                 unsigned ether_type)
90 {
91         hdr->w0 = fwnet_set_hdr_lf(RFC2374_HDR_UNFRAG)
92                   | fwnet_set_hdr_ether_type(ether_type);
93 }
94
95 static inline void fwnet_make_ff_hdr(struct rfc2734_header *hdr,
96                 unsigned ether_type, unsigned dg_size, unsigned dgl)
97 {
98         hdr->w0 = fwnet_set_hdr_lf(RFC2374_HDR_FIRSTFRAG)
99                   | fwnet_set_hdr_dg_size(dg_size)
100                   | fwnet_set_hdr_ether_type(ether_type);
101         hdr->w1 = fwnet_set_hdr_dgl(dgl);
102 }
103
104 static inline void fwnet_make_sf_hdr(struct rfc2734_header *hdr,
105                 unsigned lf, unsigned dg_size, unsigned fg_off, unsigned dgl)
106 {
107         hdr->w0 = fwnet_set_hdr_lf(lf)
108                   | fwnet_set_hdr_dg_size(dg_size)
109                   | fwnet_set_hdr_fg_off(fg_off);
110         hdr->w1 = fwnet_set_hdr_dgl(dgl);
111 }
112
113 /* This list keeps track of what parts of the datagram have been filled in */
114 struct fwnet_fragment_info {
115         struct list_head fi_link;
116         u16 offset;
117         u16 len;
118 };
119
120 struct fwnet_partial_datagram {
121         struct list_head pd_link;
122         struct list_head fi_list;
123         struct sk_buff *skb;
124         /* FIXME Why not use skb->data? */
125         char *pbuf;
126         u16 datagram_label;
127         u16 ether_type;
128         u16 datagram_size;
129 };
130
131 static DEFINE_MUTEX(fwnet_device_mutex);
132 static LIST_HEAD(fwnet_device_list);
133
134 struct fwnet_device {
135         struct list_head dev_link;
136         spinlock_t lock;
137         enum {
138                 FWNET_BROADCAST_ERROR,
139                 FWNET_BROADCAST_RUNNING,
140                 FWNET_BROADCAST_STOPPED,
141         } broadcast_state;
142         struct fw_iso_context *broadcast_rcv_context;
143         struct fw_iso_buffer broadcast_rcv_buffer;
144         void **broadcast_rcv_buffer_ptrs;
145         unsigned broadcast_rcv_next_ptr;
146         unsigned num_broadcast_rcv_ptrs;
147         unsigned rcv_buffer_size;
148         /*
149          * This value is the maximum unfragmented datagram size that can be
150          * sent by the hardware.  It already has the GASP overhead and the
151          * unfragmented datagram header overhead calculated into it.
152          */
153         unsigned broadcast_xmt_max_payload;
154         u16 broadcast_xmt_datagramlabel;
155
156         /*
157          * The CSR address that remote nodes must send datagrams to for us to
158          * receive them.
159          */
160         struct fw_address_handler handler;
161         u64 local_fifo;
162
163         /* Number of tx datagrams that have been queued but not yet acked */
164         int queued_datagrams;
165
166         int peer_count;
167         struct list_head peer_list;
168         struct fw_card *card;
169         struct net_device *netdev;
170 };
171
172 struct fwnet_peer {
173         struct list_head peer_link;
174         struct fwnet_device *dev;
175         u64 guid;
176
177         /* guarded by dev->lock */
178         struct list_head pd_list; /* received partial datagrams */
179         unsigned pdg_size;        /* pd_list size */
180
181         u16 datagram_label;       /* outgoing datagram label */
182         u16 max_payload;          /* includes RFC2374_FRAG_HDR_SIZE overhead */
183         int node_id;
184         int generation;
185         unsigned speed;
186 };
187
188 /* This is our task struct. It's used for the packet complete callback.  */
189 struct fwnet_packet_task {
190         struct fw_transaction transaction;
191         struct rfc2734_header hdr;
192         struct sk_buff *skb;
193         struct fwnet_device *dev;
194
195         int outstanding_pkts;
196         u64 fifo_addr;
197         u16 dest_node;
198         u16 max_payload;
199         u8 generation;
200         u8 speed;
201         u8 enqueued;
202 };
203
204 /*
205  * saddr == NULL means use device source address.
206  * daddr == NULL means leave destination address (eg unresolved arp).
207  */
208 static int fwnet_header_create(struct sk_buff *skb, struct net_device *net,
209                         unsigned short type, const void *daddr,
210                         const void *saddr, unsigned len)
211 {
212         struct fwnet_header *h;
213
214         h = skb_push(skb, sizeof(*h));
215         put_unaligned_be16(type, &h->h_proto);
216
217         if (net->flags & (IFF_LOOPBACK | IFF_NOARP)) {
218                 memset(h->h_dest, 0, net->addr_len);
219
220                 return net->hard_header_len;
221         }
222
223         if (daddr) {
224                 memcpy(h->h_dest, daddr, net->addr_len);
225
226                 return net->hard_header_len;
227         }
228
229         return -net->hard_header_len;
230 }
231
232 static int fwnet_header_cache(const struct neighbour *neigh,
233                               struct hh_cache *hh, __be16 type)
234 {
235         struct net_device *net;
236         struct fwnet_header *h;
237
238         if (type == cpu_to_be16(ETH_P_802_3))
239                 return -1;
240         net = neigh->dev;
241         h = (struct fwnet_header *)((u8 *)hh->hh_data + HH_DATA_OFF(sizeof(*h)));
242         h->h_proto = type;
243         memcpy(h->h_dest, neigh->ha, net->addr_len);
244
245         /* Pairs with the READ_ONCE() in neigh_resolve_output(),
246          * neigh_hh_output() and neigh_update_hhs().
247          */
248         smp_store_release(&hh->hh_len, FWNET_HLEN);
249
250         return 0;
251 }
252
253 /* Called by Address Resolution module to notify changes in address. */
254 static void fwnet_header_cache_update(struct hh_cache *hh,
255                 const struct net_device *net, const unsigned char *haddr)
256 {
257         memcpy((u8 *)hh->hh_data + HH_DATA_OFF(FWNET_HLEN), haddr, net->addr_len);
258 }
259
260 static int fwnet_header_parse(const struct sk_buff *skb, unsigned char *haddr)
261 {
262         memcpy(haddr, skb->dev->dev_addr, FWNET_ALEN);
263
264         return FWNET_ALEN;
265 }
266
267 static const struct header_ops fwnet_header_ops = {
268         .create         = fwnet_header_create,
269         .cache          = fwnet_header_cache,
270         .cache_update   = fwnet_header_cache_update,
271         .parse          = fwnet_header_parse,
272 };
273
274 /* FIXME: is this correct for all cases? */
275 static bool fwnet_frag_overlap(struct fwnet_partial_datagram *pd,
276                                unsigned offset, unsigned len)
277 {
278         struct fwnet_fragment_info *fi;
279         unsigned end = offset + len;
280
281         list_for_each_entry(fi, &pd->fi_list, fi_link)
282                 if (offset < fi->offset + fi->len && end > fi->offset)
283                         return true;
284
285         return false;
286 }
287
288 /* Assumes that new fragment does not overlap any existing fragments */
289 static struct fwnet_fragment_info *fwnet_frag_new(
290         struct fwnet_partial_datagram *pd, unsigned offset, unsigned len)
291 {
292         struct fwnet_fragment_info *fi, *fi2, *new;
293         struct list_head *list;
294
295         list = &pd->fi_list;
296         list_for_each_entry(fi, &pd->fi_list, fi_link) {
297                 if (fi->offset + fi->len == offset) {
298                         /* The new fragment can be tacked on to the end */
299                         /* Did the new fragment plug a hole? */
300                         fi2 = list_entry(fi->fi_link.next,
301                                          struct fwnet_fragment_info, fi_link);
302                         if (fi->offset + fi->len == fi2->offset) {
303                                 /* glue fragments together */
304                                 fi->len += len + fi2->len;
305                                 list_del(&fi2->fi_link);
306                                 kfree(fi2);
307                         } else {
308                                 fi->len += len;
309                         }
310
311                         return fi;
312                 }
313                 if (offset + len == fi->offset) {
314                         /* The new fragment can be tacked on to the beginning */
315                         /* Did the new fragment plug a hole? */
316                         fi2 = list_entry(fi->fi_link.prev,
317                                          struct fwnet_fragment_info, fi_link);
318                         if (fi2->offset + fi2->len == fi->offset) {
319                                 /* glue fragments together */
320                                 fi2->len += fi->len + len;
321                                 list_del(&fi->fi_link);
322                                 kfree(fi);
323
324                                 return fi2;
325                         }
326                         fi->offset = offset;
327                         fi->len += len;
328
329                         return fi;
330                 }
331                 if (offset > fi->offset + fi->len) {
332                         list = &fi->fi_link;
333                         break;
334                 }
335                 if (offset + len < fi->offset) {
336                         list = fi->fi_link.prev;
337                         break;
338                 }
339         }
340
341         new = kmalloc(sizeof(*new), GFP_ATOMIC);
342         if (!new)
343                 return NULL;
344
345         new->offset = offset;
346         new->len = len;
347         list_add(&new->fi_link, list);
348
349         return new;
350 }
351
352 static struct fwnet_partial_datagram *fwnet_pd_new(struct net_device *net,
353                 struct fwnet_peer *peer, u16 datagram_label, unsigned dg_size,
354                 void *frag_buf, unsigned frag_off, unsigned frag_len)
355 {
356         struct fwnet_partial_datagram *new;
357         struct fwnet_fragment_info *fi;
358
359         new = kmalloc(sizeof(*new), GFP_ATOMIC);
360         if (!new)
361                 goto fail;
362
363         INIT_LIST_HEAD(&new->fi_list);
364         fi = fwnet_frag_new(new, frag_off, frag_len);
365         if (fi == NULL)
366                 goto fail_w_new;
367
368         new->datagram_label = datagram_label;
369         new->datagram_size = dg_size;
370         new->skb = dev_alloc_skb(dg_size + LL_RESERVED_SPACE(net));
371         if (new->skb == NULL)
372                 goto fail_w_fi;
373
374         skb_reserve(new->skb, LL_RESERVED_SPACE(net));
375         new->pbuf = skb_put(new->skb, dg_size);
376         memcpy(new->pbuf + frag_off, frag_buf, frag_len);
377         list_add_tail(&new->pd_link, &peer->pd_list);
378
379         return new;
380
381 fail_w_fi:
382         kfree(fi);
383 fail_w_new:
384         kfree(new);
385 fail:
386         return NULL;
387 }
388
389 static struct fwnet_partial_datagram *fwnet_pd_find(struct fwnet_peer *peer,
390                                                     u16 datagram_label)
391 {
392         struct fwnet_partial_datagram *pd;
393
394         list_for_each_entry(pd, &peer->pd_list, pd_link)
395                 if (pd->datagram_label == datagram_label)
396                         return pd;
397
398         return NULL;
399 }
400
401
402 static void fwnet_pd_delete(struct fwnet_partial_datagram *old)
403 {
404         struct fwnet_fragment_info *fi, *n;
405
406         list_for_each_entry_safe(fi, n, &old->fi_list, fi_link)
407                 kfree(fi);
408
409         list_del(&old->pd_link);
410         dev_kfree_skb_any(old->skb);
411         kfree(old);
412 }
413
414 static bool fwnet_pd_update(struct fwnet_peer *peer,
415                 struct fwnet_partial_datagram *pd, void *frag_buf,
416                 unsigned frag_off, unsigned frag_len)
417 {
418         if (fwnet_frag_new(pd, frag_off, frag_len) == NULL)
419                 return false;
420
421         memcpy(pd->pbuf + frag_off, frag_buf, frag_len);
422
423         /*
424          * Move list entry to beginning of list so that oldest partial
425          * datagrams percolate to the end of the list
426          */
427         list_move_tail(&pd->pd_link, &peer->pd_list);
428
429         return true;
430 }
431
432 static bool fwnet_pd_is_complete(struct fwnet_partial_datagram *pd)
433 {
434         struct fwnet_fragment_info *fi;
435
436         fi = list_entry(pd->fi_list.next, struct fwnet_fragment_info, fi_link);
437
438         return fi->len == pd->datagram_size;
439 }
440
441 /* caller must hold dev->lock */
442 static struct fwnet_peer *fwnet_peer_find_by_guid(struct fwnet_device *dev,
443                                                   u64 guid)
444 {
445         struct fwnet_peer *peer;
446
447         list_for_each_entry(peer, &dev->peer_list, peer_link)
448                 if (peer->guid == guid)
449                         return peer;
450
451         return NULL;
452 }
453
454 /* caller must hold dev->lock */
455 static struct fwnet_peer *fwnet_peer_find_by_node_id(struct fwnet_device *dev,
456                                                 int node_id, int generation)
457 {
458         struct fwnet_peer *peer;
459
460         list_for_each_entry(peer, &dev->peer_list, peer_link)
461                 if (peer->node_id    == node_id &&
462                     peer->generation == generation)
463                         return peer;
464
465         return NULL;
466 }
467
468 /* See IEEE 1394-2008 table 6-4, table 8-8, table 16-18. */
469 static unsigned fwnet_max_payload(unsigned max_rec, unsigned speed)
470 {
471         max_rec = min(max_rec, speed + 8);
472         max_rec = clamp(max_rec, 8U, 11U); /* 512...4096 */
473
474         return (1 << (max_rec + 1)) - RFC2374_FRAG_HDR_SIZE;
475 }
476
477
478 static int fwnet_finish_incoming_packet(struct net_device *net,
479                                         struct sk_buff *skb, u16 source_node_id,
480                                         bool is_broadcast, u16 ether_type)
481 {
482         int status, len;
483
484         switch (ether_type) {
485         case ETH_P_ARP:
486         case ETH_P_IP:
487 #if IS_ENABLED(CONFIG_IPV6)
488         case ETH_P_IPV6:
489 #endif
490                 break;
491         default:
492                 goto err;
493         }
494
495         /* Write metadata, and then pass to the receive level */
496         skb->dev = net;
497         skb->ip_summed = CHECKSUM_NONE;
498
499         /*
500          * Parse the encapsulation header. This actually does the job of
501          * converting to an ethernet-like pseudo frame header.
502          */
503         if (dev_hard_header(skb, net, ether_type,
504                            is_broadcast ? net->broadcast : net->dev_addr,
505                            NULL, skb->len) >= 0) {
506                 struct fwnet_header *eth;
507                 u16 *rawp;
508                 __be16 protocol;
509
510                 skb_reset_mac_header(skb);
511                 skb_pull(skb, sizeof(*eth));
512                 eth = (struct fwnet_header *)skb_mac_header(skb);
513                 if (fwnet_hwaddr_is_multicast(eth->h_dest)) {
514                         if (memcmp(eth->h_dest, net->broadcast,
515                                    net->addr_len) == 0)
516                                 skb->pkt_type = PACKET_BROADCAST;
517 #if 0
518                         else
519                                 skb->pkt_type = PACKET_MULTICAST;
520 #endif
521                 } else {
522                         if (memcmp(eth->h_dest, net->dev_addr, net->addr_len))
523                                 skb->pkt_type = PACKET_OTHERHOST;
524                 }
525                 if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN) {
526                         protocol = eth->h_proto;
527                 } else {
528                         rawp = (u16 *)skb->data;
529                         if (*rawp == 0xffff)
530                                 protocol = htons(ETH_P_802_3);
531                         else
532                                 protocol = htons(ETH_P_802_2);
533                 }
534                 skb->protocol = protocol;
535         }
536
537         len = skb->len;
538         status = netif_rx(skb);
539         if (status == NET_RX_DROP) {
540                 net->stats.rx_errors++;
541                 net->stats.rx_dropped++;
542         } else {
543                 net->stats.rx_packets++;
544                 net->stats.rx_bytes += len;
545         }
546
547         return 0;
548
549  err:
550         net->stats.rx_errors++;
551         net->stats.rx_dropped++;
552
553         dev_kfree_skb_any(skb);
554
555         return -ENOENT;
556 }
557
558 static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
559                                  int source_node_id, int generation,
560                                  bool is_broadcast)
561 {
562         struct sk_buff *skb;
563         struct net_device *net = dev->netdev;
564         struct rfc2734_header hdr;
565         unsigned lf;
566         unsigned long flags;
567         struct fwnet_peer *peer;
568         struct fwnet_partial_datagram *pd;
569         int fg_off;
570         int dg_size;
571         u16 datagram_label;
572         int retval;
573         u16 ether_type;
574
575         if (len <= RFC2374_UNFRAG_HDR_SIZE)
576                 return 0;
577
578         hdr.w0 = be32_to_cpu(buf[0]);
579         lf = fwnet_get_hdr_lf(&hdr);
580         if (lf == RFC2374_HDR_UNFRAG) {
581                 /*
582                  * An unfragmented datagram has been received by the ieee1394
583                  * bus. Build an skbuff around it so we can pass it to the
584                  * high level network layer.
585                  */
586                 ether_type = fwnet_get_hdr_ether_type(&hdr);
587                 buf++;
588                 len -= RFC2374_UNFRAG_HDR_SIZE;
589
590                 skb = dev_alloc_skb(len + LL_RESERVED_SPACE(net));
591                 if (unlikely(!skb)) {
592                         net->stats.rx_dropped++;
593
594                         return -ENOMEM;
595                 }
596                 skb_reserve(skb, LL_RESERVED_SPACE(net));
597                 skb_put_data(skb, buf, len);
598
599                 return fwnet_finish_incoming_packet(net, skb, source_node_id,
600                                                     is_broadcast, ether_type);
601         }
602
603         /* A datagram fragment has been received, now the fun begins. */
604
605         if (len <= RFC2374_FRAG_HDR_SIZE)
606                 return 0;
607
608         hdr.w1 = ntohl(buf[1]);
609         buf += 2;
610         len -= RFC2374_FRAG_HDR_SIZE;
611         if (lf == RFC2374_HDR_FIRSTFRAG) {
612                 ether_type = fwnet_get_hdr_ether_type(&hdr);
613                 fg_off = 0;
614         } else {
615                 ether_type = 0;
616                 fg_off = fwnet_get_hdr_fg_off(&hdr);
617         }
618         datagram_label = fwnet_get_hdr_dgl(&hdr);
619         dg_size = fwnet_get_hdr_dg_size(&hdr);
620
621         if (fg_off + len > dg_size)
622                 return 0;
623
624         spin_lock_irqsave(&dev->lock, flags);
625
626         peer = fwnet_peer_find_by_node_id(dev, source_node_id, generation);
627         if (!peer) {
628                 retval = -ENOENT;
629                 goto fail;
630         }
631
632         pd = fwnet_pd_find(peer, datagram_label);
633         if (pd == NULL) {
634                 while (peer->pdg_size >= FWNET_MAX_FRAGMENTS) {
635                         /* remove the oldest */
636                         fwnet_pd_delete(list_first_entry(&peer->pd_list,
637                                 struct fwnet_partial_datagram, pd_link));
638                         peer->pdg_size--;
639                 }
640                 pd = fwnet_pd_new(net, peer, datagram_label,
641                                   dg_size, buf, fg_off, len);
642                 if (pd == NULL) {
643                         retval = -ENOMEM;
644                         goto fail;
645                 }
646                 peer->pdg_size++;
647         } else {
648                 if (fwnet_frag_overlap(pd, fg_off, len) ||
649                     pd->datagram_size != dg_size) {
650                         /*
651                          * Differing datagram sizes or overlapping fragments,
652                          * discard old datagram and start a new one.
653                          */
654                         fwnet_pd_delete(pd);
655                         pd = fwnet_pd_new(net, peer, datagram_label,
656                                           dg_size, buf, fg_off, len);
657                         if (pd == NULL) {
658                                 peer->pdg_size--;
659                                 retval = -ENOMEM;
660                                 goto fail;
661                         }
662                 } else {
663                         if (!fwnet_pd_update(peer, pd, buf, fg_off, len)) {
664                                 /*
665                                  * Couldn't save off fragment anyway
666                                  * so might as well obliterate the
667                                  * datagram now.
668                                  */
669                                 fwnet_pd_delete(pd);
670                                 peer->pdg_size--;
671                                 retval = -ENOMEM;
672                                 goto fail;
673                         }
674                 }
675         } /* new datagram or add to existing one */
676
677         if (lf == RFC2374_HDR_FIRSTFRAG)
678                 pd->ether_type = ether_type;
679
680         if (fwnet_pd_is_complete(pd)) {
681                 ether_type = pd->ether_type;
682                 peer->pdg_size--;
683                 skb = skb_get(pd->skb);
684                 fwnet_pd_delete(pd);
685
686                 spin_unlock_irqrestore(&dev->lock, flags);
687
688                 return fwnet_finish_incoming_packet(net, skb, source_node_id,
689                                                     false, ether_type);
690         }
691         /*
692          * Datagram is not complete, we're done for the
693          * moment.
694          */
695         retval = 0;
696  fail:
697         spin_unlock_irqrestore(&dev->lock, flags);
698
699         return retval;
700 }
701
702 static void fwnet_receive_packet(struct fw_card *card, struct fw_request *r,
703                 int tcode, int destination, int source, int generation,
704                 unsigned long long offset, void *payload, size_t length,
705                 void *callback_data)
706 {
707         struct fwnet_device *dev = callback_data;
708         int rcode;
709
710         if (destination == IEEE1394_ALL_NODES) {
711                 // Although the response to the broadcast packet is not necessarily required, the
712                 // fw_send_response() function should still be called to maintain the reference
713                 // counting of the object. In the case, the call of function just releases the
714                 // object as a result to decrease the reference counting.
715                 rcode = RCODE_COMPLETE;
716         } else if (offset != dev->handler.offset) {
717                 rcode = RCODE_ADDRESS_ERROR;
718         } else if (tcode != TCODE_WRITE_BLOCK_REQUEST) {
719                 rcode = RCODE_TYPE_ERROR;
720         } else if (fwnet_incoming_packet(dev, payload, length,
721                                          source, generation, false) != 0) {
722                 dev_err(&dev->netdev->dev, "incoming packet failure\n");
723                 rcode = RCODE_CONFLICT_ERROR;
724         } else {
725                 rcode = RCODE_COMPLETE;
726         }
727
728         fw_send_response(card, r, rcode);
729 }
730
731 static int gasp_source_id(__be32 *p)
732 {
733         return be32_to_cpu(p[0]) >> 16;
734 }
735
736 static u32 gasp_specifier_id(__be32 *p)
737 {
738         return (be32_to_cpu(p[0]) & 0xffff) << 8 |
739                (be32_to_cpu(p[1]) & 0xff000000) >> 24;
740 }
741
742 static u32 gasp_version(__be32 *p)
743 {
744         return be32_to_cpu(p[1]) & 0xffffff;
745 }
746
747 static void fwnet_receive_broadcast(struct fw_iso_context *context,
748                 u32 cycle, size_t header_length, void *header, void *data)
749 {
750         struct fwnet_device *dev;
751         struct fw_iso_packet packet;
752         __be16 *hdr_ptr;
753         __be32 *buf_ptr;
754         int retval;
755         u32 length;
756         unsigned long offset;
757         unsigned long flags;
758
759         dev = data;
760         hdr_ptr = header;
761         length = be16_to_cpup(hdr_ptr);
762
763         spin_lock_irqsave(&dev->lock, flags);
764
765         offset = dev->rcv_buffer_size * dev->broadcast_rcv_next_ptr;
766         buf_ptr = dev->broadcast_rcv_buffer_ptrs[dev->broadcast_rcv_next_ptr++];
767         if (dev->broadcast_rcv_next_ptr == dev->num_broadcast_rcv_ptrs)
768                 dev->broadcast_rcv_next_ptr = 0;
769
770         spin_unlock_irqrestore(&dev->lock, flags);
771
772         if (length > IEEE1394_GASP_HDR_SIZE &&
773             gasp_specifier_id(buf_ptr) == IANA_SPECIFIER_ID &&
774             (gasp_version(buf_ptr) == RFC2734_SW_VERSION
775 #if IS_ENABLED(CONFIG_IPV6)
776              || gasp_version(buf_ptr) == RFC3146_SW_VERSION
777 #endif
778             ))
779                 fwnet_incoming_packet(dev, buf_ptr + 2,
780                                       length - IEEE1394_GASP_HDR_SIZE,
781                                       gasp_source_id(buf_ptr),
782                                       context->card->generation, true);
783
784         packet.payload_length = dev->rcv_buffer_size;
785         packet.interrupt = 1;
786         packet.skip = 0;
787         packet.tag = 3;
788         packet.sy = 0;
789         packet.header_length = IEEE1394_GASP_HDR_SIZE;
790
791         spin_lock_irqsave(&dev->lock, flags);
792
793         retval = fw_iso_context_queue(dev->broadcast_rcv_context, &packet,
794                                       &dev->broadcast_rcv_buffer, offset);
795
796         spin_unlock_irqrestore(&dev->lock, flags);
797
798         if (retval >= 0)
799                 fw_iso_context_queue_flush(dev->broadcast_rcv_context);
800         else
801                 dev_err(&dev->netdev->dev, "requeue failed\n");
802 }
803
804 static struct kmem_cache *fwnet_packet_task_cache;
805
806 static void fwnet_free_ptask(struct fwnet_packet_task *ptask)
807 {
808         dev_kfree_skb_any(ptask->skb);
809         kmem_cache_free(fwnet_packet_task_cache, ptask);
810 }
811
812 /* Caller must hold dev->lock. */
813 static void dec_queued_datagrams(struct fwnet_device *dev)
814 {
815         if (--dev->queued_datagrams == FWNET_MIN_QUEUED_DATAGRAMS)
816                 netif_wake_queue(dev->netdev);
817 }
818
819 static int fwnet_send_packet(struct fwnet_packet_task *ptask);
820
821 static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
822 {
823         struct fwnet_device *dev = ptask->dev;
824         struct sk_buff *skb = ptask->skb;
825         unsigned long flags;
826         bool free;
827
828         spin_lock_irqsave(&dev->lock, flags);
829
830         ptask->outstanding_pkts--;
831
832         /* Check whether we or the networking TX soft-IRQ is last user. */
833         free = (ptask->outstanding_pkts == 0 && ptask->enqueued);
834         if (free)
835                 dec_queued_datagrams(dev);
836
837         if (ptask->outstanding_pkts == 0) {
838                 dev->netdev->stats.tx_packets++;
839                 dev->netdev->stats.tx_bytes += skb->len;
840         }
841
842         spin_unlock_irqrestore(&dev->lock, flags);
843
844         if (ptask->outstanding_pkts > 0) {
845                 u16 dg_size;
846                 u16 fg_off;
847                 u16 datagram_label;
848                 u16 lf;
849
850                 /* Update the ptask to point to the next fragment and send it */
851                 lf = fwnet_get_hdr_lf(&ptask->hdr);
852                 switch (lf) {
853                 case RFC2374_HDR_LASTFRAG:
854                 case RFC2374_HDR_UNFRAG:
855                 default:
856                         dev_err(&dev->netdev->dev,
857                                 "outstanding packet %x lf %x, header %x,%x\n",
858                                 ptask->outstanding_pkts, lf, ptask->hdr.w0,
859                                 ptask->hdr.w1);
860                         BUG();
861
862                 case RFC2374_HDR_FIRSTFRAG:
863                         /* Set frag type here for future interior fragments */
864                         dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
865                         fg_off = ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
866                         datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
867                         break;
868
869                 case RFC2374_HDR_INTFRAG:
870                         dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
871                         fg_off = fwnet_get_hdr_fg_off(&ptask->hdr)
872                                   + ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
873                         datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
874                         break;
875                 }
876
877                 if (ptask->dest_node == IEEE1394_ALL_NODES) {
878                         skb_pull(skb,
879                                  ptask->max_payload + IEEE1394_GASP_HDR_SIZE);
880                 } else {
881                         skb_pull(skb, ptask->max_payload);
882                 }
883                 if (ptask->outstanding_pkts > 1) {
884                         fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_INTFRAG,
885                                           dg_size, fg_off, datagram_label);
886                 } else {
887                         fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_LASTFRAG,
888                                           dg_size, fg_off, datagram_label);
889                         ptask->max_payload = skb->len + RFC2374_FRAG_HDR_SIZE;
890                 }
891                 fwnet_send_packet(ptask);
892         }
893
894         if (free)
895                 fwnet_free_ptask(ptask);
896 }
897
898 static void fwnet_transmit_packet_failed(struct fwnet_packet_task *ptask)
899 {
900         struct fwnet_device *dev = ptask->dev;
901         unsigned long flags;
902         bool free;
903
904         spin_lock_irqsave(&dev->lock, flags);
905
906         /* One fragment failed; don't try to send remaining fragments. */
907         ptask->outstanding_pkts = 0;
908
909         /* Check whether we or the networking TX soft-IRQ is last user. */
910         free = ptask->enqueued;
911         if (free)
912                 dec_queued_datagrams(dev);
913
914         dev->netdev->stats.tx_dropped++;
915         dev->netdev->stats.tx_errors++;
916
917         spin_unlock_irqrestore(&dev->lock, flags);
918
919         if (free)
920                 fwnet_free_ptask(ptask);
921 }
922
923 static void fwnet_write_complete(struct fw_card *card, int rcode,
924                                  void *payload, size_t length, void *data)
925 {
926         struct fwnet_packet_task *ptask = data;
927         static unsigned long j;
928         static int last_rcode, errors_skipped;
929
930         if (rcode == RCODE_COMPLETE) {
931                 fwnet_transmit_packet_done(ptask);
932         } else {
933                 if (printk_timed_ratelimit(&j,  1000) || rcode != last_rcode) {
934                         dev_err(&ptask->dev->netdev->dev,
935                                 "fwnet_write_complete failed: %x (skipped %d)\n",
936                                 rcode, errors_skipped);
937
938                         errors_skipped = 0;
939                         last_rcode = rcode;
940                 } else {
941                         errors_skipped++;
942                 }
943                 fwnet_transmit_packet_failed(ptask);
944         }
945 }
946
947 static int fwnet_send_packet(struct fwnet_packet_task *ptask)
948 {
949         struct fwnet_device *dev;
950         unsigned tx_len;
951         struct rfc2734_header *bufhdr;
952         unsigned long flags;
953         bool free;
954
955         dev = ptask->dev;
956         tx_len = ptask->max_payload;
957         switch (fwnet_get_hdr_lf(&ptask->hdr)) {
958         case RFC2374_HDR_UNFRAG:
959                 bufhdr = skb_push(ptask->skb, RFC2374_UNFRAG_HDR_SIZE);
960                 put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
961                 break;
962
963         case RFC2374_HDR_FIRSTFRAG:
964         case RFC2374_HDR_INTFRAG:
965         case RFC2374_HDR_LASTFRAG:
966                 bufhdr = skb_push(ptask->skb, RFC2374_FRAG_HDR_SIZE);
967                 put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
968                 put_unaligned_be32(ptask->hdr.w1, &bufhdr->w1);
969                 break;
970
971         default:
972                 BUG();
973         }
974         if (ptask->dest_node == IEEE1394_ALL_NODES) {
975                 u8 *p;
976                 int generation;
977                 int node_id;
978                 unsigned int sw_version;
979
980                 /* ptask->generation may not have been set yet */
981                 generation = dev->card->generation;
982                 smp_rmb();
983                 node_id = dev->card->node_id;
984
985                 switch (ptask->skb->protocol) {
986                 default:
987                         sw_version = RFC2734_SW_VERSION;
988                         break;
989 #if IS_ENABLED(CONFIG_IPV6)
990                 case htons(ETH_P_IPV6):
991                         sw_version = RFC3146_SW_VERSION;
992 #endif
993                 }
994
995                 p = skb_push(ptask->skb, IEEE1394_GASP_HDR_SIZE);
996                 put_unaligned_be32(node_id << 16 | IANA_SPECIFIER_ID >> 8, p);
997                 put_unaligned_be32((IANA_SPECIFIER_ID & 0xff) << 24
998                                                 | sw_version, &p[4]);
999
1000                 /* We should not transmit if broadcast_channel.valid == 0. */
1001                 fw_send_request(dev->card, &ptask->transaction,
1002                                 TCODE_STREAM_DATA,
1003                                 fw_stream_packet_destination_id(3,
1004                                                 IEEE1394_BROADCAST_CHANNEL, 0),
1005                                 generation, SCODE_100, 0ULL, ptask->skb->data,
1006                                 tx_len + 8, fwnet_write_complete, ptask);
1007
1008                 spin_lock_irqsave(&dev->lock, flags);
1009
1010                 /* If the AT tasklet already ran, we may be last user. */
1011                 free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1012                 if (!free)
1013                         ptask->enqueued = true;
1014                 else
1015                         dec_queued_datagrams(dev);
1016
1017                 spin_unlock_irqrestore(&dev->lock, flags);
1018
1019                 goto out;
1020         }
1021
1022         fw_send_request(dev->card, &ptask->transaction,
1023                         TCODE_WRITE_BLOCK_REQUEST, ptask->dest_node,
1024                         ptask->generation, ptask->speed, ptask->fifo_addr,
1025                         ptask->skb->data, tx_len, fwnet_write_complete, ptask);
1026
1027         spin_lock_irqsave(&dev->lock, flags);
1028
1029         /* If the AT tasklet already ran, we may be last user. */
1030         free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1031         if (!free)
1032                 ptask->enqueued = true;
1033         else
1034                 dec_queued_datagrams(dev);
1035
1036         spin_unlock_irqrestore(&dev->lock, flags);
1037
1038         netif_trans_update(dev->netdev);
1039  out:
1040         if (free)
1041                 fwnet_free_ptask(ptask);
1042
1043         return 0;
1044 }
1045
1046 static void fwnet_fifo_stop(struct fwnet_device *dev)
1047 {
1048         if (dev->local_fifo == FWNET_NO_FIFO_ADDR)
1049                 return;
1050
1051         fw_core_remove_address_handler(&dev->handler);
1052         dev->local_fifo = FWNET_NO_FIFO_ADDR;
1053 }
1054
1055 static int fwnet_fifo_start(struct fwnet_device *dev)
1056 {
1057         int retval;
1058
1059         if (dev->local_fifo != FWNET_NO_FIFO_ADDR)
1060                 return 0;
1061
1062         dev->handler.length = 4096;
1063         dev->handler.address_callback = fwnet_receive_packet;
1064         dev->handler.callback_data = dev;
1065
1066         retval = fw_core_add_address_handler(&dev->handler,
1067                                              &fw_high_memory_region);
1068         if (retval < 0)
1069                 return retval;
1070
1071         dev->local_fifo = dev->handler.offset;
1072
1073         return 0;
1074 }
1075
1076 static void __fwnet_broadcast_stop(struct fwnet_device *dev)
1077 {
1078         unsigned u;
1079
1080         if (dev->broadcast_state != FWNET_BROADCAST_ERROR) {
1081                 for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++)
1082                         kunmap(dev->broadcast_rcv_buffer.pages[u]);
1083                 fw_iso_buffer_destroy(&dev->broadcast_rcv_buffer, dev->card);
1084         }
1085         if (dev->broadcast_rcv_context) {
1086                 fw_iso_context_destroy(dev->broadcast_rcv_context);
1087                 dev->broadcast_rcv_context = NULL;
1088         }
1089         kfree(dev->broadcast_rcv_buffer_ptrs);
1090         dev->broadcast_rcv_buffer_ptrs = NULL;
1091         dev->broadcast_state = FWNET_BROADCAST_ERROR;
1092 }
1093
1094 static void fwnet_broadcast_stop(struct fwnet_device *dev)
1095 {
1096         if (dev->broadcast_state == FWNET_BROADCAST_ERROR)
1097                 return;
1098         fw_iso_context_stop(dev->broadcast_rcv_context);
1099         __fwnet_broadcast_stop(dev);
1100 }
1101
1102 static int fwnet_broadcast_start(struct fwnet_device *dev)
1103 {
1104         struct fw_iso_context *context;
1105         int retval;
1106         unsigned num_packets;
1107         unsigned max_receive;
1108         struct fw_iso_packet packet;
1109         unsigned long offset;
1110         void **ptrptr;
1111         unsigned u;
1112
1113         if (dev->broadcast_state != FWNET_BROADCAST_ERROR)
1114                 return 0;
1115
1116         max_receive = 1U << (dev->card->max_receive + 1);
1117         num_packets = (FWNET_ISO_PAGE_COUNT * PAGE_SIZE) / max_receive;
1118
1119         ptrptr = kmalloc_array(num_packets, sizeof(void *), GFP_KERNEL);
1120         if (!ptrptr) {
1121                 retval = -ENOMEM;
1122                 goto failed;
1123         }
1124         dev->broadcast_rcv_buffer_ptrs = ptrptr;
1125
1126         context = fw_iso_context_create(dev->card, FW_ISO_CONTEXT_RECEIVE,
1127                                         IEEE1394_BROADCAST_CHANNEL,
1128                                         dev->card->link_speed, 8,
1129                                         fwnet_receive_broadcast, dev);
1130         if (IS_ERR(context)) {
1131                 retval = PTR_ERR(context);
1132                 goto failed;
1133         }
1134
1135         retval = fw_iso_buffer_init(&dev->broadcast_rcv_buffer, dev->card,
1136                                     FWNET_ISO_PAGE_COUNT, DMA_FROM_DEVICE);
1137         if (retval < 0)
1138                 goto failed;
1139
1140         dev->broadcast_state = FWNET_BROADCAST_STOPPED;
1141
1142         for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++) {
1143                 void *ptr;
1144                 unsigned v;
1145
1146                 ptr = kmap(dev->broadcast_rcv_buffer.pages[u]);
1147                 for (v = 0; v < num_packets / FWNET_ISO_PAGE_COUNT; v++)
1148                         *ptrptr++ = (void *) ((char *)ptr + v * max_receive);
1149         }
1150         dev->broadcast_rcv_context = context;
1151
1152         packet.payload_length = max_receive;
1153         packet.interrupt = 1;
1154         packet.skip = 0;
1155         packet.tag = 3;
1156         packet.sy = 0;
1157         packet.header_length = IEEE1394_GASP_HDR_SIZE;
1158         offset = 0;
1159
1160         for (u = 0; u < num_packets; u++) {
1161                 retval = fw_iso_context_queue(context, &packet,
1162                                 &dev->broadcast_rcv_buffer, offset);
1163                 if (retval < 0)
1164                         goto failed;
1165
1166                 offset += max_receive;
1167         }
1168         dev->num_broadcast_rcv_ptrs = num_packets;
1169         dev->rcv_buffer_size = max_receive;
1170         dev->broadcast_rcv_next_ptr = 0U;
1171         retval = fw_iso_context_start(context, -1, 0,
1172                         FW_ISO_CONTEXT_MATCH_ALL_TAGS); /* ??? sync */
1173         if (retval < 0)
1174                 goto failed;
1175
1176         /* FIXME: adjust it according to the min. speed of all known peers? */
1177         dev->broadcast_xmt_max_payload = IEEE1394_MAX_PAYLOAD_S100
1178                         - IEEE1394_GASP_HDR_SIZE - RFC2374_UNFRAG_HDR_SIZE;
1179         dev->broadcast_state = FWNET_BROADCAST_RUNNING;
1180
1181         return 0;
1182
1183  failed:
1184         __fwnet_broadcast_stop(dev);
1185         return retval;
1186 }
1187
1188 static void set_carrier_state(struct fwnet_device *dev)
1189 {
1190         if (dev->peer_count > 1)
1191                 netif_carrier_on(dev->netdev);
1192         else
1193                 netif_carrier_off(dev->netdev);
1194 }
1195
1196 /* ifup */
1197 static int fwnet_open(struct net_device *net)
1198 {
1199         struct fwnet_device *dev = netdev_priv(net);
1200         int ret;
1201
1202         ret = fwnet_broadcast_start(dev);
1203         if (ret)
1204                 return ret;
1205
1206         netif_start_queue(net);
1207
1208         spin_lock_irq(&dev->lock);
1209         set_carrier_state(dev);
1210         spin_unlock_irq(&dev->lock);
1211
1212         return 0;
1213 }
1214
1215 /* ifdown */
1216 static int fwnet_stop(struct net_device *net)
1217 {
1218         struct fwnet_device *dev = netdev_priv(net);
1219
1220         netif_stop_queue(net);
1221         fwnet_broadcast_stop(dev);
1222
1223         return 0;
1224 }
1225
1226 static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
1227 {
1228         struct fwnet_header hdr_buf;
1229         struct fwnet_device *dev = netdev_priv(net);
1230         __be16 proto;
1231         u16 dest_node;
1232         unsigned max_payload;
1233         u16 dg_size;
1234         u16 *datagram_label_ptr;
1235         struct fwnet_packet_task *ptask;
1236         struct fwnet_peer *peer;
1237         unsigned long flags;
1238
1239         spin_lock_irqsave(&dev->lock, flags);
1240
1241         /* Can this happen? */
1242         if (netif_queue_stopped(dev->netdev)) {
1243                 spin_unlock_irqrestore(&dev->lock, flags);
1244
1245                 return NETDEV_TX_BUSY;
1246         }
1247
1248         ptask = kmem_cache_alloc(fwnet_packet_task_cache, GFP_ATOMIC);
1249         if (ptask == NULL)
1250                 goto fail;
1251
1252         skb = skb_share_check(skb, GFP_ATOMIC);
1253         if (!skb)
1254                 goto fail;
1255
1256         /*
1257          * Make a copy of the driver-specific header.
1258          * We might need to rebuild the header on tx failure.
1259          */
1260         memcpy(&hdr_buf, skb->data, sizeof(hdr_buf));
1261         proto = hdr_buf.h_proto;
1262
1263         switch (proto) {
1264         case htons(ETH_P_ARP):
1265         case htons(ETH_P_IP):
1266 #if IS_ENABLED(CONFIG_IPV6)
1267         case htons(ETH_P_IPV6):
1268 #endif
1269                 break;
1270         default:
1271                 goto fail;
1272         }
1273
1274         skb_pull(skb, sizeof(hdr_buf));
1275         dg_size = skb->len;
1276
1277         /*
1278          * Set the transmission type for the packet.  ARP packets and IP
1279          * broadcast packets are sent via GASP.
1280          */
1281         if (fwnet_hwaddr_is_multicast(hdr_buf.h_dest)) {
1282                 max_payload        = dev->broadcast_xmt_max_payload;
1283                 datagram_label_ptr = &dev->broadcast_xmt_datagramlabel;
1284
1285                 ptask->fifo_addr   = FWNET_NO_FIFO_ADDR;
1286                 ptask->generation  = 0;
1287                 ptask->dest_node   = IEEE1394_ALL_NODES;
1288                 ptask->speed       = SCODE_100;
1289         } else {
1290                 union fwnet_hwaddr *ha = (union fwnet_hwaddr *)hdr_buf.h_dest;
1291                 __be64 guid = get_unaligned(&ha->uc.uniq_id);
1292                 u8 generation;
1293
1294                 peer = fwnet_peer_find_by_guid(dev, be64_to_cpu(guid));
1295                 if (!peer)
1296                         goto fail;
1297
1298                 generation         = peer->generation;
1299                 dest_node          = peer->node_id;
1300                 max_payload        = peer->max_payload;
1301                 datagram_label_ptr = &peer->datagram_label;
1302
1303                 ptask->fifo_addr   = get_unaligned_be48(ha->uc.fifo);
1304                 ptask->generation  = generation;
1305                 ptask->dest_node   = dest_node;
1306                 ptask->speed       = peer->speed;
1307         }
1308
1309         ptask->hdr.w0 = 0;
1310         ptask->hdr.w1 = 0;
1311         ptask->skb = skb;
1312         ptask->dev = dev;
1313
1314         /* Does it all fit in one packet? */
1315         if (dg_size <= max_payload) {
1316                 fwnet_make_uf_hdr(&ptask->hdr, ntohs(proto));
1317                 ptask->outstanding_pkts = 1;
1318                 max_payload = dg_size + RFC2374_UNFRAG_HDR_SIZE;
1319         } else {
1320                 u16 datagram_label;
1321
1322                 max_payload -= RFC2374_FRAG_OVERHEAD;
1323                 datagram_label = (*datagram_label_ptr)++;
1324                 fwnet_make_ff_hdr(&ptask->hdr, ntohs(proto), dg_size,
1325                                   datagram_label);
1326                 ptask->outstanding_pkts = DIV_ROUND_UP(dg_size, max_payload);
1327                 max_payload += RFC2374_FRAG_HDR_SIZE;
1328         }
1329
1330         if (++dev->queued_datagrams == FWNET_MAX_QUEUED_DATAGRAMS)
1331                 netif_stop_queue(dev->netdev);
1332
1333         spin_unlock_irqrestore(&dev->lock, flags);
1334
1335         ptask->max_payload = max_payload;
1336         ptask->enqueued    = 0;
1337
1338         fwnet_send_packet(ptask);
1339
1340         return NETDEV_TX_OK;
1341
1342  fail:
1343         spin_unlock_irqrestore(&dev->lock, flags);
1344
1345         if (ptask)
1346                 kmem_cache_free(fwnet_packet_task_cache, ptask);
1347
1348         if (skb != NULL)
1349                 dev_kfree_skb(skb);
1350
1351         net->stats.tx_dropped++;
1352         net->stats.tx_errors++;
1353
1354         /*
1355          * FIXME: According to a patch from 2003-02-26, "returning non-zero
1356          * causes serious problems" here, allegedly.  Before that patch,
1357          * -ERRNO was returned which is not appropriate under Linux 2.6.
1358          * Perhaps more needs to be done?  Stop the queue in serious
1359          * conditions and restart it elsewhere?
1360          */
1361         return NETDEV_TX_OK;
1362 }
1363
1364 static const struct ethtool_ops fwnet_ethtool_ops = {
1365         .get_link       = ethtool_op_get_link,
1366 };
1367
1368 static const struct net_device_ops fwnet_netdev_ops = {
1369         .ndo_open       = fwnet_open,
1370         .ndo_stop       = fwnet_stop,
1371         .ndo_start_xmit = fwnet_tx,
1372 };
1373
1374 static void fwnet_init_dev(struct net_device *net)
1375 {
1376         net->header_ops         = &fwnet_header_ops;
1377         net->netdev_ops         = &fwnet_netdev_ops;
1378         net->watchdog_timeo     = 2 * HZ;
1379         net->flags              = IFF_BROADCAST | IFF_MULTICAST;
1380         net->features           = NETIF_F_HIGHDMA;
1381         net->addr_len           = FWNET_ALEN;
1382         net->hard_header_len    = FWNET_HLEN;
1383         net->type               = ARPHRD_IEEE1394;
1384         net->tx_queue_len       = FWNET_TX_QUEUE_LEN;
1385         net->ethtool_ops        = &fwnet_ethtool_ops;
1386 }
1387
1388 /* caller must hold fwnet_device_mutex */
1389 static struct fwnet_device *fwnet_dev_find(struct fw_card *card)
1390 {
1391         struct fwnet_device *dev;
1392
1393         list_for_each_entry(dev, &fwnet_device_list, dev_link)
1394                 if (dev->card == card)
1395                         return dev;
1396
1397         return NULL;
1398 }
1399
1400 static int fwnet_add_peer(struct fwnet_device *dev,
1401                           struct fw_unit *unit, struct fw_device *device)
1402 {
1403         struct fwnet_peer *peer;
1404
1405         peer = kmalloc(sizeof(*peer), GFP_KERNEL);
1406         if (!peer)
1407                 return -ENOMEM;
1408
1409         dev_set_drvdata(&unit->device, peer);
1410
1411         peer->dev = dev;
1412         peer->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1413         INIT_LIST_HEAD(&peer->pd_list);
1414         peer->pdg_size = 0;
1415         peer->datagram_label = 0;
1416         peer->speed = device->max_speed;
1417         peer->max_payload = fwnet_max_payload(device->max_rec, peer->speed);
1418
1419         peer->generation = device->generation;
1420         smp_rmb();
1421         peer->node_id = device->node_id;
1422
1423         spin_lock_irq(&dev->lock);
1424         list_add_tail(&peer->peer_link, &dev->peer_list);
1425         dev->peer_count++;
1426         set_carrier_state(dev);
1427         spin_unlock_irq(&dev->lock);
1428
1429         return 0;
1430 }
1431
1432 static int fwnet_probe(struct fw_unit *unit,
1433                        const struct ieee1394_device_id *id)
1434 {
1435         struct fw_device *device = fw_parent_device(unit);
1436         struct fw_card *card = device->card;
1437         struct net_device *net;
1438         bool allocated_netdev = false;
1439         struct fwnet_device *dev;
1440         union fwnet_hwaddr ha;
1441         int ret;
1442
1443         mutex_lock(&fwnet_device_mutex);
1444
1445         dev = fwnet_dev_find(card);
1446         if (dev) {
1447                 net = dev->netdev;
1448                 goto have_dev;
1449         }
1450
1451         net = alloc_netdev(sizeof(*dev), "firewire%d", NET_NAME_UNKNOWN,
1452                            fwnet_init_dev);
1453         if (net == NULL) {
1454                 mutex_unlock(&fwnet_device_mutex);
1455                 return -ENOMEM;
1456         }
1457
1458         allocated_netdev = true;
1459         SET_NETDEV_DEV(net, card->device);
1460         dev = netdev_priv(net);
1461
1462         spin_lock_init(&dev->lock);
1463         dev->broadcast_state = FWNET_BROADCAST_ERROR;
1464         dev->broadcast_rcv_context = NULL;
1465         dev->broadcast_xmt_max_payload = 0;
1466         dev->broadcast_xmt_datagramlabel = 0;
1467         dev->local_fifo = FWNET_NO_FIFO_ADDR;
1468         dev->queued_datagrams = 0;
1469         INIT_LIST_HEAD(&dev->peer_list);
1470         dev->card = card;
1471         dev->netdev = net;
1472
1473         ret = fwnet_fifo_start(dev);
1474         if (ret < 0)
1475                 goto out;
1476         dev->local_fifo = dev->handler.offset;
1477
1478         /*
1479          * default MTU: RFC 2734 cl. 4, RFC 3146 cl. 4
1480          * maximum MTU: RFC 2734 cl. 4.2, fragment encapsulation header's
1481          *              maximum possible datagram_size + 1 = 0xfff + 1
1482          */
1483         net->mtu = 1500U;
1484         net->min_mtu = ETH_MIN_MTU;
1485         net->max_mtu = 4096U;
1486
1487         /* Set our hardware address while we're at it */
1488         ha.uc.uniq_id = cpu_to_be64(card->guid);
1489         ha.uc.max_rec = dev->card->max_receive;
1490         ha.uc.sspd = dev->card->link_speed;
1491         put_unaligned_be48(dev->local_fifo, ha.uc.fifo);
1492         dev_addr_set(net, ha.u);
1493
1494         memset(net->broadcast, -1, net->addr_len);
1495
1496         ret = register_netdev(net);
1497         if (ret)
1498                 goto out;
1499
1500         list_add_tail(&dev->dev_link, &fwnet_device_list);
1501         dev_notice(&net->dev, "IP over IEEE 1394 on card %s\n",
1502                    dev_name(card->device));
1503  have_dev:
1504         ret = fwnet_add_peer(dev, unit, device);
1505         if (ret && allocated_netdev) {
1506                 unregister_netdev(net);
1507                 list_del(&dev->dev_link);
1508  out:
1509                 fwnet_fifo_stop(dev);
1510                 free_netdev(net);
1511         }
1512
1513         mutex_unlock(&fwnet_device_mutex);
1514
1515         return ret;
1516 }
1517
1518 /*
1519  * FIXME abort partially sent fragmented datagrams,
1520  * discard partially received fragmented datagrams
1521  */
1522 static void fwnet_update(struct fw_unit *unit)
1523 {
1524         struct fw_device *device = fw_parent_device(unit);
1525         struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1526         int generation;
1527
1528         generation = device->generation;
1529
1530         spin_lock_irq(&peer->dev->lock);
1531         peer->node_id    = device->node_id;
1532         peer->generation = generation;
1533         spin_unlock_irq(&peer->dev->lock);
1534 }
1535
1536 static void fwnet_remove_peer(struct fwnet_peer *peer, struct fwnet_device *dev)
1537 {
1538         struct fwnet_partial_datagram *pd, *pd_next;
1539
1540         spin_lock_irq(&dev->lock);
1541         list_del(&peer->peer_link);
1542         dev->peer_count--;
1543         set_carrier_state(dev);
1544         spin_unlock_irq(&dev->lock);
1545
1546         list_for_each_entry_safe(pd, pd_next, &peer->pd_list, pd_link)
1547                 fwnet_pd_delete(pd);
1548
1549         kfree(peer);
1550 }
1551
1552 static void fwnet_remove(struct fw_unit *unit)
1553 {
1554         struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1555         struct fwnet_device *dev = peer->dev;
1556         struct net_device *net;
1557         int i;
1558
1559         mutex_lock(&fwnet_device_mutex);
1560
1561         net = dev->netdev;
1562
1563         fwnet_remove_peer(peer, dev);
1564
1565         if (list_empty(&dev->peer_list)) {
1566                 unregister_netdev(net);
1567
1568                 fwnet_fifo_stop(dev);
1569
1570                 for (i = 0; dev->queued_datagrams && i < 5; i++)
1571                         ssleep(1);
1572                 WARN_ON(dev->queued_datagrams);
1573                 list_del(&dev->dev_link);
1574
1575                 free_netdev(net);
1576         }
1577
1578         mutex_unlock(&fwnet_device_mutex);
1579 }
1580
1581 static const struct ieee1394_device_id fwnet_id_table[] = {
1582         {
1583                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1584                                 IEEE1394_MATCH_VERSION,
1585                 .specifier_id = IANA_SPECIFIER_ID,
1586                 .version      = RFC2734_SW_VERSION,
1587         },
1588 #if IS_ENABLED(CONFIG_IPV6)
1589         {
1590                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1591                                 IEEE1394_MATCH_VERSION,
1592                 .specifier_id = IANA_SPECIFIER_ID,
1593                 .version      = RFC3146_SW_VERSION,
1594         },
1595 #endif
1596         { }
1597 };
1598
1599 static struct fw_driver fwnet_driver = {
1600         .driver = {
1601                 .owner  = THIS_MODULE,
1602                 .name   = KBUILD_MODNAME,
1603                 .bus    = &fw_bus_type,
1604         },
1605         .probe    = fwnet_probe,
1606         .update   = fwnet_update,
1607         .remove   = fwnet_remove,
1608         .id_table = fwnet_id_table,
1609 };
1610
1611 static const u32 rfc2374_unit_directory_data[] = {
1612         0x00040000,     /* directory_length             */
1613         0x1200005e,     /* unit_specifier_id: IANA      */
1614         0x81000003,     /* textual descriptor offset    */
1615         0x13000001,     /* unit_sw_version: RFC 2734    */
1616         0x81000005,     /* textual descriptor offset    */
1617         0x00030000,     /* descriptor_length            */
1618         0x00000000,     /* text                         */
1619         0x00000000,     /* minimal ASCII, en            */
1620         0x49414e41,     /* I A N A                      */
1621         0x00030000,     /* descriptor_length            */
1622         0x00000000,     /* text                         */
1623         0x00000000,     /* minimal ASCII, en            */
1624         0x49507634,     /* I P v 4                      */
1625 };
1626
1627 static struct fw_descriptor rfc2374_unit_directory = {
1628         .length = ARRAY_SIZE(rfc2374_unit_directory_data),
1629         .key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1630         .data   = rfc2374_unit_directory_data
1631 };
1632
1633 #if IS_ENABLED(CONFIG_IPV6)
1634 static const u32 rfc3146_unit_directory_data[] = {
1635         0x00040000,     /* directory_length             */
1636         0x1200005e,     /* unit_specifier_id: IANA      */
1637         0x81000003,     /* textual descriptor offset    */
1638         0x13000002,     /* unit_sw_version: RFC 3146    */
1639         0x81000005,     /* textual descriptor offset    */
1640         0x00030000,     /* descriptor_length            */
1641         0x00000000,     /* text                         */
1642         0x00000000,     /* minimal ASCII, en            */
1643         0x49414e41,     /* I A N A                      */
1644         0x00030000,     /* descriptor_length            */
1645         0x00000000,     /* text                         */
1646         0x00000000,     /* minimal ASCII, en            */
1647         0x49507636,     /* I P v 6                      */
1648 };
1649
1650 static struct fw_descriptor rfc3146_unit_directory = {
1651         .length = ARRAY_SIZE(rfc3146_unit_directory_data),
1652         .key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1653         .data   = rfc3146_unit_directory_data
1654 };
1655 #endif
1656
1657 static int __init fwnet_init(void)
1658 {
1659         int err;
1660
1661         err = fw_core_add_descriptor(&rfc2374_unit_directory);
1662         if (err)
1663                 return err;
1664
1665 #if IS_ENABLED(CONFIG_IPV6)
1666         err = fw_core_add_descriptor(&rfc3146_unit_directory);
1667         if (err)
1668                 goto out;
1669 #endif
1670
1671         fwnet_packet_task_cache = kmem_cache_create("packet_task",
1672                         sizeof(struct fwnet_packet_task), 0, 0, NULL);
1673         if (!fwnet_packet_task_cache) {
1674                 err = -ENOMEM;
1675                 goto out2;
1676         }
1677
1678         err = driver_register(&fwnet_driver.driver);
1679         if (!err)
1680                 return 0;
1681
1682         kmem_cache_destroy(fwnet_packet_task_cache);
1683 out2:
1684 #if IS_ENABLED(CONFIG_IPV6)
1685         fw_core_remove_descriptor(&rfc3146_unit_directory);
1686 out:
1687 #endif
1688         fw_core_remove_descriptor(&rfc2374_unit_directory);
1689
1690         return err;
1691 }
1692 module_init(fwnet_init);
1693
1694 static void __exit fwnet_cleanup(void)
1695 {
1696         driver_unregister(&fwnet_driver.driver);
1697         kmem_cache_destroy(fwnet_packet_task_cache);
1698 #if IS_ENABLED(CONFIG_IPV6)
1699         fw_core_remove_descriptor(&rfc3146_unit_directory);
1700 #endif
1701         fw_core_remove_descriptor(&rfc2374_unit_directory);
1702 }
1703 module_exit(fwnet_cleanup);
1704
1705 MODULE_AUTHOR("Jay Fenlason <fenlason@redhat.com>");
1706 MODULE_DESCRIPTION("IP over IEEE1394 as per RFC 2734/3146");
1707 MODULE_LICENSE("GPL");
1708 MODULE_DEVICE_TABLE(ieee1394, fwnet_id_table);