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
64static bool fwnet_hwaddr_is_multicast(u8 *ha)
65{
66	return !!(*ha & 1);
67}
68
69/* IPv4 and IPv6 encapsulation header */
70struct 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
88static 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
95static 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
104static 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 */
114struct fwnet_fragment_info {
115	struct list_head fi_link;
116	u16 offset;
117	u16 len;
118};
119
120struct 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
131static DEFINE_MUTEX(fwnet_device_mutex);
132static LIST_HEAD(fwnet_device_list);
133
134struct 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
172struct 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.  */
189struct 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 */
208static 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
232static 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. */
254static 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
260static 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
267static 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? */
275static 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 */
289static 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
352static 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
381fail_w_fi:
382	kfree(fi);
383fail_w_new:
384	kfree(new);
385fail:
386	return NULL;
387}
388
389static 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
402static 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
414static 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
432static 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 */
442static 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 */
455static 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. */
469static 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
478static 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
558static 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
702static 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
731static int gasp_source_id(__be32 *p)
732{
733	return be32_to_cpu(p[0]) >> 16;
734}
735
736static 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
742static u32 gasp_version(__be32 *p)
743{
744	return be32_to_cpu(p[1]) & 0xffffff;
745}
746
747static 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
804static struct kmem_cache *fwnet_packet_task_cache;
805
806static 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. */
813static 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
819static int fwnet_send_packet(struct fwnet_packet_task *ptask);
820
821static 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
898static 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
923static 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
947static 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
1046static 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
1055static 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
1076static 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
1094static 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
1102static 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
1188static 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 */
1197static 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 */
1216static 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
1226static 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
1364static const struct ethtool_ops fwnet_ethtool_ops = {
1365	.get_link	= ethtool_op_get_link,
1366};
1367
1368static 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
1374static 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 */
1389static 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
1400static 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
1432static 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 */
1522static 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
1536static 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
1552static 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
1581static 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
1599static 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
1611static 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
1627static 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)
1634static 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
1650static 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
1657static 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);
1683out2:
1684#if IS_ENABLED(CONFIG_IPV6)
1685	fw_core_remove_descriptor(&rfc3146_unit_directory);
1686out:
1687#endif
1688	fw_core_remove_descriptor(&rfc2374_unit_directory);
1689
1690	return err;
1691}
1692module_init(fwnet_init);
1693
1694static 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}
1703module_exit(fwnet_cleanup);
1704
1705MODULE_AUTHOR("Jay Fenlason <fenlason@redhat.com>");
1706MODULE_DESCRIPTION("IP over IEEE1394 as per RFC 2734/3146");
1707MODULE_LICENSE("GPL");
1708MODULE_DEVICE_TABLE(ieee1394, fwnet_id_table);
1709