xref: /kernel/linux/linux-5.10/drivers/firewire/net.c (revision 8c2ecf20)
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 * Get fifo address embedded in hwaddr
206 */
207static __u64 fwnet_hwaddr_fifo(union fwnet_hwaddr *ha)
208{
209	return (u64)get_unaligned_be16(&ha->uc.fifo_hi) << 32
210	       | get_unaligned_be32(&ha->uc.fifo_lo);
211}
212
213/*
214 * saddr == NULL means use device source address.
215 * daddr == NULL means leave destination address (eg unresolved arp).
216 */
217static int fwnet_header_create(struct sk_buff *skb, struct net_device *net,
218			unsigned short type, const void *daddr,
219			const void *saddr, unsigned len)
220{
221	struct fwnet_header *h;
222
223	h = skb_push(skb, sizeof(*h));
224	put_unaligned_be16(type, &h->h_proto);
225
226	if (net->flags & (IFF_LOOPBACK | IFF_NOARP)) {
227		memset(h->h_dest, 0, net->addr_len);
228
229		return net->hard_header_len;
230	}
231
232	if (daddr) {
233		memcpy(h->h_dest, daddr, net->addr_len);
234
235		return net->hard_header_len;
236	}
237
238	return -net->hard_header_len;
239}
240
241static int fwnet_header_cache(const struct neighbour *neigh,
242			      struct hh_cache *hh, __be16 type)
243{
244	struct net_device *net;
245	struct fwnet_header *h;
246
247	if (type == cpu_to_be16(ETH_P_802_3))
248		return -1;
249	net = neigh->dev;
250	h = (struct fwnet_header *)((u8 *)hh->hh_data + HH_DATA_OFF(sizeof(*h)));
251	h->h_proto = type;
252	memcpy(h->h_dest, neigh->ha, net->addr_len);
253
254	/* Pairs with the READ_ONCE() in neigh_resolve_output(),
255	 * neigh_hh_output() and neigh_update_hhs().
256	 */
257	smp_store_release(&hh->hh_len, FWNET_HLEN);
258
259	return 0;
260}
261
262/* Called by Address Resolution module to notify changes in address. */
263static void fwnet_header_cache_update(struct hh_cache *hh,
264		const struct net_device *net, const unsigned char *haddr)
265{
266	memcpy((u8 *)hh->hh_data + HH_DATA_OFF(FWNET_HLEN), haddr, net->addr_len);
267}
268
269static int fwnet_header_parse(const struct sk_buff *skb, unsigned char *haddr)
270{
271	memcpy(haddr, skb->dev->dev_addr, FWNET_ALEN);
272
273	return FWNET_ALEN;
274}
275
276static const struct header_ops fwnet_header_ops = {
277	.create         = fwnet_header_create,
278	.cache		= fwnet_header_cache,
279	.cache_update	= fwnet_header_cache_update,
280	.parse          = fwnet_header_parse,
281};
282
283/* FIXME: is this correct for all cases? */
284static bool fwnet_frag_overlap(struct fwnet_partial_datagram *pd,
285			       unsigned offset, unsigned len)
286{
287	struct fwnet_fragment_info *fi;
288	unsigned end = offset + len;
289
290	list_for_each_entry(fi, &pd->fi_list, fi_link)
291		if (offset < fi->offset + fi->len && end > fi->offset)
292			return true;
293
294	return false;
295}
296
297/* Assumes that new fragment does not overlap any existing fragments */
298static struct fwnet_fragment_info *fwnet_frag_new(
299	struct fwnet_partial_datagram *pd, unsigned offset, unsigned len)
300{
301	struct fwnet_fragment_info *fi, *fi2, *new;
302	struct list_head *list;
303
304	list = &pd->fi_list;
305	list_for_each_entry(fi, &pd->fi_list, fi_link) {
306		if (fi->offset + fi->len == offset) {
307			/* The new fragment can be tacked on to the end */
308			/* Did the new fragment plug a hole? */
309			fi2 = list_entry(fi->fi_link.next,
310					 struct fwnet_fragment_info, fi_link);
311			if (fi->offset + fi->len == fi2->offset) {
312				/* glue fragments together */
313				fi->len += len + fi2->len;
314				list_del(&fi2->fi_link);
315				kfree(fi2);
316			} else {
317				fi->len += len;
318			}
319
320			return fi;
321		}
322		if (offset + len == fi->offset) {
323			/* The new fragment can be tacked on to the beginning */
324			/* Did the new fragment plug a hole? */
325			fi2 = list_entry(fi->fi_link.prev,
326					 struct fwnet_fragment_info, fi_link);
327			if (fi2->offset + fi2->len == fi->offset) {
328				/* glue fragments together */
329				fi2->len += fi->len + len;
330				list_del(&fi->fi_link);
331				kfree(fi);
332
333				return fi2;
334			}
335			fi->offset = offset;
336			fi->len += len;
337
338			return fi;
339		}
340		if (offset > fi->offset + fi->len) {
341			list = &fi->fi_link;
342			break;
343		}
344		if (offset + len < fi->offset) {
345			list = fi->fi_link.prev;
346			break;
347		}
348	}
349
350	new = kmalloc(sizeof(*new), GFP_ATOMIC);
351	if (!new)
352		return NULL;
353
354	new->offset = offset;
355	new->len = len;
356	list_add(&new->fi_link, list);
357
358	return new;
359}
360
361static struct fwnet_partial_datagram *fwnet_pd_new(struct net_device *net,
362		struct fwnet_peer *peer, u16 datagram_label, unsigned dg_size,
363		void *frag_buf, unsigned frag_off, unsigned frag_len)
364{
365	struct fwnet_partial_datagram *new;
366	struct fwnet_fragment_info *fi;
367
368	new = kmalloc(sizeof(*new), GFP_ATOMIC);
369	if (!new)
370		goto fail;
371
372	INIT_LIST_HEAD(&new->fi_list);
373	fi = fwnet_frag_new(new, frag_off, frag_len);
374	if (fi == NULL)
375		goto fail_w_new;
376
377	new->datagram_label = datagram_label;
378	new->datagram_size = dg_size;
379	new->skb = dev_alloc_skb(dg_size + LL_RESERVED_SPACE(net));
380	if (new->skb == NULL)
381		goto fail_w_fi;
382
383	skb_reserve(new->skb, LL_RESERVED_SPACE(net));
384	new->pbuf = skb_put(new->skb, dg_size);
385	memcpy(new->pbuf + frag_off, frag_buf, frag_len);
386	list_add_tail(&new->pd_link, &peer->pd_list);
387
388	return new;
389
390fail_w_fi:
391	kfree(fi);
392fail_w_new:
393	kfree(new);
394fail:
395	return NULL;
396}
397
398static struct fwnet_partial_datagram *fwnet_pd_find(struct fwnet_peer *peer,
399						    u16 datagram_label)
400{
401	struct fwnet_partial_datagram *pd;
402
403	list_for_each_entry(pd, &peer->pd_list, pd_link)
404		if (pd->datagram_label == datagram_label)
405			return pd;
406
407	return NULL;
408}
409
410
411static void fwnet_pd_delete(struct fwnet_partial_datagram *old)
412{
413	struct fwnet_fragment_info *fi, *n;
414
415	list_for_each_entry_safe(fi, n, &old->fi_list, fi_link)
416		kfree(fi);
417
418	list_del(&old->pd_link);
419	dev_kfree_skb_any(old->skb);
420	kfree(old);
421}
422
423static bool fwnet_pd_update(struct fwnet_peer *peer,
424		struct fwnet_partial_datagram *pd, void *frag_buf,
425		unsigned frag_off, unsigned frag_len)
426{
427	if (fwnet_frag_new(pd, frag_off, frag_len) == NULL)
428		return false;
429
430	memcpy(pd->pbuf + frag_off, frag_buf, frag_len);
431
432	/*
433	 * Move list entry to beginning of list so that oldest partial
434	 * datagrams percolate to the end of the list
435	 */
436	list_move_tail(&pd->pd_link, &peer->pd_list);
437
438	return true;
439}
440
441static bool fwnet_pd_is_complete(struct fwnet_partial_datagram *pd)
442{
443	struct fwnet_fragment_info *fi;
444
445	fi = list_entry(pd->fi_list.next, struct fwnet_fragment_info, fi_link);
446
447	return fi->len == pd->datagram_size;
448}
449
450/* caller must hold dev->lock */
451static struct fwnet_peer *fwnet_peer_find_by_guid(struct fwnet_device *dev,
452						  u64 guid)
453{
454	struct fwnet_peer *peer;
455
456	list_for_each_entry(peer, &dev->peer_list, peer_link)
457		if (peer->guid == guid)
458			return peer;
459
460	return NULL;
461}
462
463/* caller must hold dev->lock */
464static struct fwnet_peer *fwnet_peer_find_by_node_id(struct fwnet_device *dev,
465						int node_id, int generation)
466{
467	struct fwnet_peer *peer;
468
469	list_for_each_entry(peer, &dev->peer_list, peer_link)
470		if (peer->node_id    == node_id &&
471		    peer->generation == generation)
472			return peer;
473
474	return NULL;
475}
476
477/* See IEEE 1394-2008 table 6-4, table 8-8, table 16-18. */
478static unsigned fwnet_max_payload(unsigned max_rec, unsigned speed)
479{
480	max_rec = min(max_rec, speed + 8);
481	max_rec = clamp(max_rec, 8U, 11U); /* 512...4096 */
482
483	return (1 << (max_rec + 1)) - RFC2374_FRAG_HDR_SIZE;
484}
485
486
487static int fwnet_finish_incoming_packet(struct net_device *net,
488					struct sk_buff *skb, u16 source_node_id,
489					bool is_broadcast, u16 ether_type)
490{
491	struct fwnet_device *dev;
492	int status;
493	__be64 guid;
494
495	switch (ether_type) {
496	case ETH_P_ARP:
497	case ETH_P_IP:
498#if IS_ENABLED(CONFIG_IPV6)
499	case ETH_P_IPV6:
500#endif
501		break;
502	default:
503		goto err;
504	}
505
506	dev = netdev_priv(net);
507	/* Write metadata, and then pass to the receive level */
508	skb->dev = net;
509	skb->ip_summed = CHECKSUM_NONE;
510
511	/*
512	 * Parse the encapsulation header. This actually does the job of
513	 * converting to an ethernet-like pseudo frame header.
514	 */
515	guid = cpu_to_be64(dev->card->guid);
516	if (dev_hard_header(skb, net, ether_type,
517			   is_broadcast ? net->broadcast : net->dev_addr,
518			   NULL, skb->len) >= 0) {
519		struct fwnet_header *eth;
520		u16 *rawp;
521		__be16 protocol;
522
523		skb_reset_mac_header(skb);
524		skb_pull(skb, sizeof(*eth));
525		eth = (struct fwnet_header *)skb_mac_header(skb);
526		if (fwnet_hwaddr_is_multicast(eth->h_dest)) {
527			if (memcmp(eth->h_dest, net->broadcast,
528				   net->addr_len) == 0)
529				skb->pkt_type = PACKET_BROADCAST;
530#if 0
531			else
532				skb->pkt_type = PACKET_MULTICAST;
533#endif
534		} else {
535			if (memcmp(eth->h_dest, net->dev_addr, net->addr_len))
536				skb->pkt_type = PACKET_OTHERHOST;
537		}
538		if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN) {
539			protocol = eth->h_proto;
540		} else {
541			rawp = (u16 *)skb->data;
542			if (*rawp == 0xffff)
543				protocol = htons(ETH_P_802_3);
544			else
545				protocol = htons(ETH_P_802_2);
546		}
547		skb->protocol = protocol;
548	}
549	status = netif_rx(skb);
550	if (status == NET_RX_DROP) {
551		net->stats.rx_errors++;
552		net->stats.rx_dropped++;
553	} else {
554		net->stats.rx_packets++;
555		net->stats.rx_bytes += skb->len;
556	}
557
558	return 0;
559
560 err:
561	net->stats.rx_errors++;
562	net->stats.rx_dropped++;
563
564	dev_kfree_skb_any(skb);
565
566	return -ENOENT;
567}
568
569static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
570				 int source_node_id, int generation,
571				 bool is_broadcast)
572{
573	struct sk_buff *skb;
574	struct net_device *net = dev->netdev;
575	struct rfc2734_header hdr;
576	unsigned lf;
577	unsigned long flags;
578	struct fwnet_peer *peer;
579	struct fwnet_partial_datagram *pd;
580	int fg_off;
581	int dg_size;
582	u16 datagram_label;
583	int retval;
584	u16 ether_type;
585
586	if (len <= RFC2374_UNFRAG_HDR_SIZE)
587		return 0;
588
589	hdr.w0 = be32_to_cpu(buf[0]);
590	lf = fwnet_get_hdr_lf(&hdr);
591	if (lf == RFC2374_HDR_UNFRAG) {
592		/*
593		 * An unfragmented datagram has been received by the ieee1394
594		 * bus. Build an skbuff around it so we can pass it to the
595		 * high level network layer.
596		 */
597		ether_type = fwnet_get_hdr_ether_type(&hdr);
598		buf++;
599		len -= RFC2374_UNFRAG_HDR_SIZE;
600
601		skb = dev_alloc_skb(len + LL_RESERVED_SPACE(net));
602		if (unlikely(!skb)) {
603			net->stats.rx_dropped++;
604
605			return -ENOMEM;
606		}
607		skb_reserve(skb, LL_RESERVED_SPACE(net));
608		skb_put_data(skb, buf, len);
609
610		return fwnet_finish_incoming_packet(net, skb, source_node_id,
611						    is_broadcast, ether_type);
612	}
613
614	/* A datagram fragment has been received, now the fun begins. */
615
616	if (len <= RFC2374_FRAG_HDR_SIZE)
617		return 0;
618
619	hdr.w1 = ntohl(buf[1]);
620	buf += 2;
621	len -= RFC2374_FRAG_HDR_SIZE;
622	if (lf == RFC2374_HDR_FIRSTFRAG) {
623		ether_type = fwnet_get_hdr_ether_type(&hdr);
624		fg_off = 0;
625	} else {
626		ether_type = 0;
627		fg_off = fwnet_get_hdr_fg_off(&hdr);
628	}
629	datagram_label = fwnet_get_hdr_dgl(&hdr);
630	dg_size = fwnet_get_hdr_dg_size(&hdr);
631
632	if (fg_off + len > dg_size)
633		return 0;
634
635	spin_lock_irqsave(&dev->lock, flags);
636
637	peer = fwnet_peer_find_by_node_id(dev, source_node_id, generation);
638	if (!peer) {
639		retval = -ENOENT;
640		goto fail;
641	}
642
643	pd = fwnet_pd_find(peer, datagram_label);
644	if (pd == NULL) {
645		while (peer->pdg_size >= FWNET_MAX_FRAGMENTS) {
646			/* remove the oldest */
647			fwnet_pd_delete(list_first_entry(&peer->pd_list,
648				struct fwnet_partial_datagram, pd_link));
649			peer->pdg_size--;
650		}
651		pd = fwnet_pd_new(net, peer, datagram_label,
652				  dg_size, buf, fg_off, len);
653		if (pd == NULL) {
654			retval = -ENOMEM;
655			goto fail;
656		}
657		peer->pdg_size++;
658	} else {
659		if (fwnet_frag_overlap(pd, fg_off, len) ||
660		    pd->datagram_size != dg_size) {
661			/*
662			 * Differing datagram sizes or overlapping fragments,
663			 * discard old datagram and start a new one.
664			 */
665			fwnet_pd_delete(pd);
666			pd = fwnet_pd_new(net, peer, datagram_label,
667					  dg_size, buf, fg_off, len);
668			if (pd == NULL) {
669				peer->pdg_size--;
670				retval = -ENOMEM;
671				goto fail;
672			}
673		} else {
674			if (!fwnet_pd_update(peer, pd, buf, fg_off, len)) {
675				/*
676				 * Couldn't save off fragment anyway
677				 * so might as well obliterate the
678				 * datagram now.
679				 */
680				fwnet_pd_delete(pd);
681				peer->pdg_size--;
682				retval = -ENOMEM;
683				goto fail;
684			}
685		}
686	} /* new datagram or add to existing one */
687
688	if (lf == RFC2374_HDR_FIRSTFRAG)
689		pd->ether_type = ether_type;
690
691	if (fwnet_pd_is_complete(pd)) {
692		ether_type = pd->ether_type;
693		peer->pdg_size--;
694		skb = skb_get(pd->skb);
695		fwnet_pd_delete(pd);
696
697		spin_unlock_irqrestore(&dev->lock, flags);
698
699		return fwnet_finish_incoming_packet(net, skb, source_node_id,
700						    false, ether_type);
701	}
702	/*
703	 * Datagram is not complete, we're done for the
704	 * moment.
705	 */
706	retval = 0;
707 fail:
708	spin_unlock_irqrestore(&dev->lock, flags);
709
710	return retval;
711}
712
713static void fwnet_receive_packet(struct fw_card *card, struct fw_request *r,
714		int tcode, int destination, int source, int generation,
715		unsigned long long offset, void *payload, size_t length,
716		void *callback_data)
717{
718	struct fwnet_device *dev = callback_data;
719	int rcode;
720
721	if (destination == IEEE1394_ALL_NODES) {
722		kfree(r);
723
724		return;
725	}
726
727	if (offset != dev->handler.offset)
728		rcode = RCODE_ADDRESS_ERROR;
729	else if (tcode != TCODE_WRITE_BLOCK_REQUEST)
730		rcode = RCODE_TYPE_ERROR;
731	else if (fwnet_incoming_packet(dev, payload, length,
732				       source, generation, false) != 0) {
733		dev_err(&dev->netdev->dev, "incoming packet failure\n");
734		rcode = RCODE_CONFLICT_ERROR;
735	} else
736		rcode = RCODE_COMPLETE;
737
738	fw_send_response(card, r, rcode);
739}
740
741static int gasp_source_id(__be32 *p)
742{
743	return be32_to_cpu(p[0]) >> 16;
744}
745
746static u32 gasp_specifier_id(__be32 *p)
747{
748	return (be32_to_cpu(p[0]) & 0xffff) << 8 |
749	       (be32_to_cpu(p[1]) & 0xff000000) >> 24;
750}
751
752static u32 gasp_version(__be32 *p)
753{
754	return be32_to_cpu(p[1]) & 0xffffff;
755}
756
757static void fwnet_receive_broadcast(struct fw_iso_context *context,
758		u32 cycle, size_t header_length, void *header, void *data)
759{
760	struct fwnet_device *dev;
761	struct fw_iso_packet packet;
762	__be16 *hdr_ptr;
763	__be32 *buf_ptr;
764	int retval;
765	u32 length;
766	unsigned long offset;
767	unsigned long flags;
768
769	dev = data;
770	hdr_ptr = header;
771	length = be16_to_cpup(hdr_ptr);
772
773	spin_lock_irqsave(&dev->lock, flags);
774
775	offset = dev->rcv_buffer_size * dev->broadcast_rcv_next_ptr;
776	buf_ptr = dev->broadcast_rcv_buffer_ptrs[dev->broadcast_rcv_next_ptr++];
777	if (dev->broadcast_rcv_next_ptr == dev->num_broadcast_rcv_ptrs)
778		dev->broadcast_rcv_next_ptr = 0;
779
780	spin_unlock_irqrestore(&dev->lock, flags);
781
782	if (length > IEEE1394_GASP_HDR_SIZE &&
783	    gasp_specifier_id(buf_ptr) == IANA_SPECIFIER_ID &&
784	    (gasp_version(buf_ptr) == RFC2734_SW_VERSION
785#if IS_ENABLED(CONFIG_IPV6)
786	     || gasp_version(buf_ptr) == RFC3146_SW_VERSION
787#endif
788	    ))
789		fwnet_incoming_packet(dev, buf_ptr + 2,
790				      length - IEEE1394_GASP_HDR_SIZE,
791				      gasp_source_id(buf_ptr),
792				      context->card->generation, true);
793
794	packet.payload_length = dev->rcv_buffer_size;
795	packet.interrupt = 1;
796	packet.skip = 0;
797	packet.tag = 3;
798	packet.sy = 0;
799	packet.header_length = IEEE1394_GASP_HDR_SIZE;
800
801	spin_lock_irqsave(&dev->lock, flags);
802
803	retval = fw_iso_context_queue(dev->broadcast_rcv_context, &packet,
804				      &dev->broadcast_rcv_buffer, offset);
805
806	spin_unlock_irqrestore(&dev->lock, flags);
807
808	if (retval >= 0)
809		fw_iso_context_queue_flush(dev->broadcast_rcv_context);
810	else
811		dev_err(&dev->netdev->dev, "requeue failed\n");
812}
813
814static struct kmem_cache *fwnet_packet_task_cache;
815
816static void fwnet_free_ptask(struct fwnet_packet_task *ptask)
817{
818	dev_kfree_skb_any(ptask->skb);
819	kmem_cache_free(fwnet_packet_task_cache, ptask);
820}
821
822/* Caller must hold dev->lock. */
823static void dec_queued_datagrams(struct fwnet_device *dev)
824{
825	if (--dev->queued_datagrams == FWNET_MIN_QUEUED_DATAGRAMS)
826		netif_wake_queue(dev->netdev);
827}
828
829static int fwnet_send_packet(struct fwnet_packet_task *ptask);
830
831static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
832{
833	struct fwnet_device *dev = ptask->dev;
834	struct sk_buff *skb = ptask->skb;
835	unsigned long flags;
836	bool free;
837
838	spin_lock_irqsave(&dev->lock, flags);
839
840	ptask->outstanding_pkts--;
841
842	/* Check whether we or the networking TX soft-IRQ is last user. */
843	free = (ptask->outstanding_pkts == 0 && ptask->enqueued);
844	if (free)
845		dec_queued_datagrams(dev);
846
847	if (ptask->outstanding_pkts == 0) {
848		dev->netdev->stats.tx_packets++;
849		dev->netdev->stats.tx_bytes += skb->len;
850	}
851
852	spin_unlock_irqrestore(&dev->lock, flags);
853
854	if (ptask->outstanding_pkts > 0) {
855		u16 dg_size;
856		u16 fg_off;
857		u16 datagram_label;
858		u16 lf;
859
860		/* Update the ptask to point to the next fragment and send it */
861		lf = fwnet_get_hdr_lf(&ptask->hdr);
862		switch (lf) {
863		case RFC2374_HDR_LASTFRAG:
864		case RFC2374_HDR_UNFRAG:
865		default:
866			dev_err(&dev->netdev->dev,
867				"outstanding packet %x lf %x, header %x,%x\n",
868				ptask->outstanding_pkts, lf, ptask->hdr.w0,
869				ptask->hdr.w1);
870			BUG();
871
872		case RFC2374_HDR_FIRSTFRAG:
873			/* Set frag type here for future interior fragments */
874			dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
875			fg_off = ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
876			datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
877			break;
878
879		case RFC2374_HDR_INTFRAG:
880			dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
881			fg_off = fwnet_get_hdr_fg_off(&ptask->hdr)
882				  + ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
883			datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
884			break;
885		}
886
887		if (ptask->dest_node == IEEE1394_ALL_NODES) {
888			skb_pull(skb,
889				 ptask->max_payload + IEEE1394_GASP_HDR_SIZE);
890		} else {
891			skb_pull(skb, ptask->max_payload);
892		}
893		if (ptask->outstanding_pkts > 1) {
894			fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_INTFRAG,
895					  dg_size, fg_off, datagram_label);
896		} else {
897			fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_LASTFRAG,
898					  dg_size, fg_off, datagram_label);
899			ptask->max_payload = skb->len + RFC2374_FRAG_HDR_SIZE;
900		}
901		fwnet_send_packet(ptask);
902	}
903
904	if (free)
905		fwnet_free_ptask(ptask);
906}
907
908static void fwnet_transmit_packet_failed(struct fwnet_packet_task *ptask)
909{
910	struct fwnet_device *dev = ptask->dev;
911	unsigned long flags;
912	bool free;
913
914	spin_lock_irqsave(&dev->lock, flags);
915
916	/* One fragment failed; don't try to send remaining fragments. */
917	ptask->outstanding_pkts = 0;
918
919	/* Check whether we or the networking TX soft-IRQ is last user. */
920	free = ptask->enqueued;
921	if (free)
922		dec_queued_datagrams(dev);
923
924	dev->netdev->stats.tx_dropped++;
925	dev->netdev->stats.tx_errors++;
926
927	spin_unlock_irqrestore(&dev->lock, flags);
928
929	if (free)
930		fwnet_free_ptask(ptask);
931}
932
933static void fwnet_write_complete(struct fw_card *card, int rcode,
934				 void *payload, size_t length, void *data)
935{
936	struct fwnet_packet_task *ptask = data;
937	static unsigned long j;
938	static int last_rcode, errors_skipped;
939
940	if (rcode == RCODE_COMPLETE) {
941		fwnet_transmit_packet_done(ptask);
942	} else {
943		if (printk_timed_ratelimit(&j,  1000) || rcode != last_rcode) {
944			dev_err(&ptask->dev->netdev->dev,
945				"fwnet_write_complete failed: %x (skipped %d)\n",
946				rcode, errors_skipped);
947
948			errors_skipped = 0;
949			last_rcode = rcode;
950		} else {
951			errors_skipped++;
952		}
953		fwnet_transmit_packet_failed(ptask);
954	}
955}
956
957static int fwnet_send_packet(struct fwnet_packet_task *ptask)
958{
959	struct fwnet_device *dev;
960	unsigned tx_len;
961	struct rfc2734_header *bufhdr;
962	unsigned long flags;
963	bool free;
964
965	dev = ptask->dev;
966	tx_len = ptask->max_payload;
967	switch (fwnet_get_hdr_lf(&ptask->hdr)) {
968	case RFC2374_HDR_UNFRAG:
969		bufhdr = skb_push(ptask->skb, RFC2374_UNFRAG_HDR_SIZE);
970		put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
971		break;
972
973	case RFC2374_HDR_FIRSTFRAG:
974	case RFC2374_HDR_INTFRAG:
975	case RFC2374_HDR_LASTFRAG:
976		bufhdr = skb_push(ptask->skb, RFC2374_FRAG_HDR_SIZE);
977		put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
978		put_unaligned_be32(ptask->hdr.w1, &bufhdr->w1);
979		break;
980
981	default:
982		BUG();
983	}
984	if (ptask->dest_node == IEEE1394_ALL_NODES) {
985		u8 *p;
986		int generation;
987		int node_id;
988		unsigned int sw_version;
989
990		/* ptask->generation may not have been set yet */
991		generation = dev->card->generation;
992		smp_rmb();
993		node_id = dev->card->node_id;
994
995		switch (ptask->skb->protocol) {
996		default:
997			sw_version = RFC2734_SW_VERSION;
998			break;
999#if IS_ENABLED(CONFIG_IPV6)
1000		case htons(ETH_P_IPV6):
1001			sw_version = RFC3146_SW_VERSION;
1002#endif
1003		}
1004
1005		p = skb_push(ptask->skb, IEEE1394_GASP_HDR_SIZE);
1006		put_unaligned_be32(node_id << 16 | IANA_SPECIFIER_ID >> 8, p);
1007		put_unaligned_be32((IANA_SPECIFIER_ID & 0xff) << 24
1008						| sw_version, &p[4]);
1009
1010		/* We should not transmit if broadcast_channel.valid == 0. */
1011		fw_send_request(dev->card, &ptask->transaction,
1012				TCODE_STREAM_DATA,
1013				fw_stream_packet_destination_id(3,
1014						IEEE1394_BROADCAST_CHANNEL, 0),
1015				generation, SCODE_100, 0ULL, ptask->skb->data,
1016				tx_len + 8, fwnet_write_complete, ptask);
1017
1018		spin_lock_irqsave(&dev->lock, flags);
1019
1020		/* If the AT tasklet already ran, we may be last user. */
1021		free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1022		if (!free)
1023			ptask->enqueued = true;
1024		else
1025			dec_queued_datagrams(dev);
1026
1027		spin_unlock_irqrestore(&dev->lock, flags);
1028
1029		goto out;
1030	}
1031
1032	fw_send_request(dev->card, &ptask->transaction,
1033			TCODE_WRITE_BLOCK_REQUEST, ptask->dest_node,
1034			ptask->generation, ptask->speed, ptask->fifo_addr,
1035			ptask->skb->data, tx_len, fwnet_write_complete, ptask);
1036
1037	spin_lock_irqsave(&dev->lock, flags);
1038
1039	/* If the AT tasklet already ran, we may be last user. */
1040	free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1041	if (!free)
1042		ptask->enqueued = true;
1043	else
1044		dec_queued_datagrams(dev);
1045
1046	spin_unlock_irqrestore(&dev->lock, flags);
1047
1048	netif_trans_update(dev->netdev);
1049 out:
1050	if (free)
1051		fwnet_free_ptask(ptask);
1052
1053	return 0;
1054}
1055
1056static void fwnet_fifo_stop(struct fwnet_device *dev)
1057{
1058	if (dev->local_fifo == FWNET_NO_FIFO_ADDR)
1059		return;
1060
1061	fw_core_remove_address_handler(&dev->handler);
1062	dev->local_fifo = FWNET_NO_FIFO_ADDR;
1063}
1064
1065static int fwnet_fifo_start(struct fwnet_device *dev)
1066{
1067	int retval;
1068
1069	if (dev->local_fifo != FWNET_NO_FIFO_ADDR)
1070		return 0;
1071
1072	dev->handler.length = 4096;
1073	dev->handler.address_callback = fwnet_receive_packet;
1074	dev->handler.callback_data = dev;
1075
1076	retval = fw_core_add_address_handler(&dev->handler,
1077					     &fw_high_memory_region);
1078	if (retval < 0)
1079		return retval;
1080
1081	dev->local_fifo = dev->handler.offset;
1082
1083	return 0;
1084}
1085
1086static void __fwnet_broadcast_stop(struct fwnet_device *dev)
1087{
1088	unsigned u;
1089
1090	if (dev->broadcast_state != FWNET_BROADCAST_ERROR) {
1091		for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++)
1092			kunmap(dev->broadcast_rcv_buffer.pages[u]);
1093		fw_iso_buffer_destroy(&dev->broadcast_rcv_buffer, dev->card);
1094	}
1095	if (dev->broadcast_rcv_context) {
1096		fw_iso_context_destroy(dev->broadcast_rcv_context);
1097		dev->broadcast_rcv_context = NULL;
1098	}
1099	kfree(dev->broadcast_rcv_buffer_ptrs);
1100	dev->broadcast_rcv_buffer_ptrs = NULL;
1101	dev->broadcast_state = FWNET_BROADCAST_ERROR;
1102}
1103
1104static void fwnet_broadcast_stop(struct fwnet_device *dev)
1105{
1106	if (dev->broadcast_state == FWNET_BROADCAST_ERROR)
1107		return;
1108	fw_iso_context_stop(dev->broadcast_rcv_context);
1109	__fwnet_broadcast_stop(dev);
1110}
1111
1112static int fwnet_broadcast_start(struct fwnet_device *dev)
1113{
1114	struct fw_iso_context *context;
1115	int retval;
1116	unsigned num_packets;
1117	unsigned max_receive;
1118	struct fw_iso_packet packet;
1119	unsigned long offset;
1120	void **ptrptr;
1121	unsigned u;
1122
1123	if (dev->broadcast_state != FWNET_BROADCAST_ERROR)
1124		return 0;
1125
1126	max_receive = 1U << (dev->card->max_receive + 1);
1127	num_packets = (FWNET_ISO_PAGE_COUNT * PAGE_SIZE) / max_receive;
1128
1129	ptrptr = kmalloc_array(num_packets, sizeof(void *), GFP_KERNEL);
1130	if (!ptrptr) {
1131		retval = -ENOMEM;
1132		goto failed;
1133	}
1134	dev->broadcast_rcv_buffer_ptrs = ptrptr;
1135
1136	context = fw_iso_context_create(dev->card, FW_ISO_CONTEXT_RECEIVE,
1137					IEEE1394_BROADCAST_CHANNEL,
1138					dev->card->link_speed, 8,
1139					fwnet_receive_broadcast, dev);
1140	if (IS_ERR(context)) {
1141		retval = PTR_ERR(context);
1142		goto failed;
1143	}
1144
1145	retval = fw_iso_buffer_init(&dev->broadcast_rcv_buffer, dev->card,
1146				    FWNET_ISO_PAGE_COUNT, DMA_FROM_DEVICE);
1147	if (retval < 0)
1148		goto failed;
1149
1150	dev->broadcast_state = FWNET_BROADCAST_STOPPED;
1151
1152	for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++) {
1153		void *ptr;
1154		unsigned v;
1155
1156		ptr = kmap(dev->broadcast_rcv_buffer.pages[u]);
1157		for (v = 0; v < num_packets / FWNET_ISO_PAGE_COUNT; v++)
1158			*ptrptr++ = (void *) ((char *)ptr + v * max_receive);
1159	}
1160	dev->broadcast_rcv_context = context;
1161
1162	packet.payload_length = max_receive;
1163	packet.interrupt = 1;
1164	packet.skip = 0;
1165	packet.tag = 3;
1166	packet.sy = 0;
1167	packet.header_length = IEEE1394_GASP_HDR_SIZE;
1168	offset = 0;
1169
1170	for (u = 0; u < num_packets; u++) {
1171		retval = fw_iso_context_queue(context, &packet,
1172				&dev->broadcast_rcv_buffer, offset);
1173		if (retval < 0)
1174			goto failed;
1175
1176		offset += max_receive;
1177	}
1178	dev->num_broadcast_rcv_ptrs = num_packets;
1179	dev->rcv_buffer_size = max_receive;
1180	dev->broadcast_rcv_next_ptr = 0U;
1181	retval = fw_iso_context_start(context, -1, 0,
1182			FW_ISO_CONTEXT_MATCH_ALL_TAGS); /* ??? sync */
1183	if (retval < 0)
1184		goto failed;
1185
1186	/* FIXME: adjust it according to the min. speed of all known peers? */
1187	dev->broadcast_xmt_max_payload = IEEE1394_MAX_PAYLOAD_S100
1188			- IEEE1394_GASP_HDR_SIZE - RFC2374_UNFRAG_HDR_SIZE;
1189	dev->broadcast_state = FWNET_BROADCAST_RUNNING;
1190
1191	return 0;
1192
1193 failed:
1194	__fwnet_broadcast_stop(dev);
1195	return retval;
1196}
1197
1198static void set_carrier_state(struct fwnet_device *dev)
1199{
1200	if (dev->peer_count > 1)
1201		netif_carrier_on(dev->netdev);
1202	else
1203		netif_carrier_off(dev->netdev);
1204}
1205
1206/* ifup */
1207static int fwnet_open(struct net_device *net)
1208{
1209	struct fwnet_device *dev = netdev_priv(net);
1210	int ret;
1211
1212	ret = fwnet_broadcast_start(dev);
1213	if (ret)
1214		return ret;
1215
1216	netif_start_queue(net);
1217
1218	spin_lock_irq(&dev->lock);
1219	set_carrier_state(dev);
1220	spin_unlock_irq(&dev->lock);
1221
1222	return 0;
1223}
1224
1225/* ifdown */
1226static int fwnet_stop(struct net_device *net)
1227{
1228	struct fwnet_device *dev = netdev_priv(net);
1229
1230	netif_stop_queue(net);
1231	fwnet_broadcast_stop(dev);
1232
1233	return 0;
1234}
1235
1236static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
1237{
1238	struct fwnet_header hdr_buf;
1239	struct fwnet_device *dev = netdev_priv(net);
1240	__be16 proto;
1241	u16 dest_node;
1242	unsigned max_payload;
1243	u16 dg_size;
1244	u16 *datagram_label_ptr;
1245	struct fwnet_packet_task *ptask;
1246	struct fwnet_peer *peer;
1247	unsigned long flags;
1248
1249	spin_lock_irqsave(&dev->lock, flags);
1250
1251	/* Can this happen? */
1252	if (netif_queue_stopped(dev->netdev)) {
1253		spin_unlock_irqrestore(&dev->lock, flags);
1254
1255		return NETDEV_TX_BUSY;
1256	}
1257
1258	ptask = kmem_cache_alloc(fwnet_packet_task_cache, GFP_ATOMIC);
1259	if (ptask == NULL)
1260		goto fail;
1261
1262	skb = skb_share_check(skb, GFP_ATOMIC);
1263	if (!skb)
1264		goto fail;
1265
1266	/*
1267	 * Make a copy of the driver-specific header.
1268	 * We might need to rebuild the header on tx failure.
1269	 */
1270	memcpy(&hdr_buf, skb->data, sizeof(hdr_buf));
1271	proto = hdr_buf.h_proto;
1272
1273	switch (proto) {
1274	case htons(ETH_P_ARP):
1275	case htons(ETH_P_IP):
1276#if IS_ENABLED(CONFIG_IPV6)
1277	case htons(ETH_P_IPV6):
1278#endif
1279		break;
1280	default:
1281		goto fail;
1282	}
1283
1284	skb_pull(skb, sizeof(hdr_buf));
1285	dg_size = skb->len;
1286
1287	/*
1288	 * Set the transmission type for the packet.  ARP packets and IP
1289	 * broadcast packets are sent via GASP.
1290	 */
1291	if (fwnet_hwaddr_is_multicast(hdr_buf.h_dest)) {
1292		max_payload        = dev->broadcast_xmt_max_payload;
1293		datagram_label_ptr = &dev->broadcast_xmt_datagramlabel;
1294
1295		ptask->fifo_addr   = FWNET_NO_FIFO_ADDR;
1296		ptask->generation  = 0;
1297		ptask->dest_node   = IEEE1394_ALL_NODES;
1298		ptask->speed       = SCODE_100;
1299	} else {
1300		union fwnet_hwaddr *ha = (union fwnet_hwaddr *)hdr_buf.h_dest;
1301		__be64 guid = get_unaligned(&ha->uc.uniq_id);
1302		u8 generation;
1303
1304		peer = fwnet_peer_find_by_guid(dev, be64_to_cpu(guid));
1305		if (!peer)
1306			goto fail;
1307
1308		generation         = peer->generation;
1309		dest_node          = peer->node_id;
1310		max_payload        = peer->max_payload;
1311		datagram_label_ptr = &peer->datagram_label;
1312
1313		ptask->fifo_addr   = fwnet_hwaddr_fifo(ha);
1314		ptask->generation  = generation;
1315		ptask->dest_node   = dest_node;
1316		ptask->speed       = peer->speed;
1317	}
1318
1319	ptask->hdr.w0 = 0;
1320	ptask->hdr.w1 = 0;
1321	ptask->skb = skb;
1322	ptask->dev = dev;
1323
1324	/* Does it all fit in one packet? */
1325	if (dg_size <= max_payload) {
1326		fwnet_make_uf_hdr(&ptask->hdr, ntohs(proto));
1327		ptask->outstanding_pkts = 1;
1328		max_payload = dg_size + RFC2374_UNFRAG_HDR_SIZE;
1329	} else {
1330		u16 datagram_label;
1331
1332		max_payload -= RFC2374_FRAG_OVERHEAD;
1333		datagram_label = (*datagram_label_ptr)++;
1334		fwnet_make_ff_hdr(&ptask->hdr, ntohs(proto), dg_size,
1335				  datagram_label);
1336		ptask->outstanding_pkts = DIV_ROUND_UP(dg_size, max_payload);
1337		max_payload += RFC2374_FRAG_HDR_SIZE;
1338	}
1339
1340	if (++dev->queued_datagrams == FWNET_MAX_QUEUED_DATAGRAMS)
1341		netif_stop_queue(dev->netdev);
1342
1343	spin_unlock_irqrestore(&dev->lock, flags);
1344
1345	ptask->max_payload = max_payload;
1346	ptask->enqueued    = 0;
1347
1348	fwnet_send_packet(ptask);
1349
1350	return NETDEV_TX_OK;
1351
1352 fail:
1353	spin_unlock_irqrestore(&dev->lock, flags);
1354
1355	if (ptask)
1356		kmem_cache_free(fwnet_packet_task_cache, ptask);
1357
1358	if (skb != NULL)
1359		dev_kfree_skb(skb);
1360
1361	net->stats.tx_dropped++;
1362	net->stats.tx_errors++;
1363
1364	/*
1365	 * FIXME: According to a patch from 2003-02-26, "returning non-zero
1366	 * causes serious problems" here, allegedly.  Before that patch,
1367	 * -ERRNO was returned which is not appropriate under Linux 2.6.
1368	 * Perhaps more needs to be done?  Stop the queue in serious
1369	 * conditions and restart it elsewhere?
1370	 */
1371	return NETDEV_TX_OK;
1372}
1373
1374static const struct ethtool_ops fwnet_ethtool_ops = {
1375	.get_link	= ethtool_op_get_link,
1376};
1377
1378static const struct net_device_ops fwnet_netdev_ops = {
1379	.ndo_open       = fwnet_open,
1380	.ndo_stop	= fwnet_stop,
1381	.ndo_start_xmit = fwnet_tx,
1382};
1383
1384static void fwnet_init_dev(struct net_device *net)
1385{
1386	net->header_ops		= &fwnet_header_ops;
1387	net->netdev_ops		= &fwnet_netdev_ops;
1388	net->watchdog_timeo	= 2 * HZ;
1389	net->flags		= IFF_BROADCAST | IFF_MULTICAST;
1390	net->features		= NETIF_F_HIGHDMA;
1391	net->addr_len		= FWNET_ALEN;
1392	net->hard_header_len	= FWNET_HLEN;
1393	net->type		= ARPHRD_IEEE1394;
1394	net->tx_queue_len	= FWNET_TX_QUEUE_LEN;
1395	net->ethtool_ops	= &fwnet_ethtool_ops;
1396}
1397
1398/* caller must hold fwnet_device_mutex */
1399static struct fwnet_device *fwnet_dev_find(struct fw_card *card)
1400{
1401	struct fwnet_device *dev;
1402
1403	list_for_each_entry(dev, &fwnet_device_list, dev_link)
1404		if (dev->card == card)
1405			return dev;
1406
1407	return NULL;
1408}
1409
1410static int fwnet_add_peer(struct fwnet_device *dev,
1411			  struct fw_unit *unit, struct fw_device *device)
1412{
1413	struct fwnet_peer *peer;
1414
1415	peer = kmalloc(sizeof(*peer), GFP_KERNEL);
1416	if (!peer)
1417		return -ENOMEM;
1418
1419	dev_set_drvdata(&unit->device, peer);
1420
1421	peer->dev = dev;
1422	peer->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1423	INIT_LIST_HEAD(&peer->pd_list);
1424	peer->pdg_size = 0;
1425	peer->datagram_label = 0;
1426	peer->speed = device->max_speed;
1427	peer->max_payload = fwnet_max_payload(device->max_rec, peer->speed);
1428
1429	peer->generation = device->generation;
1430	smp_rmb();
1431	peer->node_id = device->node_id;
1432
1433	spin_lock_irq(&dev->lock);
1434	list_add_tail(&peer->peer_link, &dev->peer_list);
1435	dev->peer_count++;
1436	set_carrier_state(dev);
1437	spin_unlock_irq(&dev->lock);
1438
1439	return 0;
1440}
1441
1442static int fwnet_probe(struct fw_unit *unit,
1443		       const struct ieee1394_device_id *id)
1444{
1445	struct fw_device *device = fw_parent_device(unit);
1446	struct fw_card *card = device->card;
1447	struct net_device *net;
1448	bool allocated_netdev = false;
1449	struct fwnet_device *dev;
1450	int ret;
1451	union fwnet_hwaddr *ha;
1452
1453	mutex_lock(&fwnet_device_mutex);
1454
1455	dev = fwnet_dev_find(card);
1456	if (dev) {
1457		net = dev->netdev;
1458		goto have_dev;
1459	}
1460
1461	net = alloc_netdev(sizeof(*dev), "firewire%d", NET_NAME_UNKNOWN,
1462			   fwnet_init_dev);
1463	if (net == NULL) {
1464		mutex_unlock(&fwnet_device_mutex);
1465		return -ENOMEM;
1466	}
1467
1468	allocated_netdev = true;
1469	SET_NETDEV_DEV(net, card->device);
1470	dev = netdev_priv(net);
1471
1472	spin_lock_init(&dev->lock);
1473	dev->broadcast_state = FWNET_BROADCAST_ERROR;
1474	dev->broadcast_rcv_context = NULL;
1475	dev->broadcast_xmt_max_payload = 0;
1476	dev->broadcast_xmt_datagramlabel = 0;
1477	dev->local_fifo = FWNET_NO_FIFO_ADDR;
1478	dev->queued_datagrams = 0;
1479	INIT_LIST_HEAD(&dev->peer_list);
1480	dev->card = card;
1481	dev->netdev = net;
1482
1483	ret = fwnet_fifo_start(dev);
1484	if (ret < 0)
1485		goto out;
1486	dev->local_fifo = dev->handler.offset;
1487
1488	/*
1489	 * default MTU: RFC 2734 cl. 4, RFC 3146 cl. 4
1490	 * maximum MTU: RFC 2734 cl. 4.2, fragment encapsulation header's
1491	 *              maximum possible datagram_size + 1 = 0xfff + 1
1492	 */
1493	net->mtu = 1500U;
1494	net->min_mtu = ETH_MIN_MTU;
1495	net->max_mtu = 4096U;
1496
1497	/* Set our hardware address while we're at it */
1498	ha = (union fwnet_hwaddr *)net->dev_addr;
1499	put_unaligned_be64(card->guid, &ha->uc.uniq_id);
1500	ha->uc.max_rec = dev->card->max_receive;
1501	ha->uc.sspd = dev->card->link_speed;
1502	put_unaligned_be16(dev->local_fifo >> 32, &ha->uc.fifo_hi);
1503	put_unaligned_be32(dev->local_fifo & 0xffffffff, &ha->uc.fifo_lo);
1504
1505	memset(net->broadcast, -1, net->addr_len);
1506
1507	ret = register_netdev(net);
1508	if (ret)
1509		goto out;
1510
1511	list_add_tail(&dev->dev_link, &fwnet_device_list);
1512	dev_notice(&net->dev, "IP over IEEE 1394 on card %s\n",
1513		   dev_name(card->device));
1514 have_dev:
1515	ret = fwnet_add_peer(dev, unit, device);
1516	if (ret && allocated_netdev) {
1517		unregister_netdev(net);
1518		list_del(&dev->dev_link);
1519 out:
1520		fwnet_fifo_stop(dev);
1521		free_netdev(net);
1522	}
1523
1524	mutex_unlock(&fwnet_device_mutex);
1525
1526	return ret;
1527}
1528
1529/*
1530 * FIXME abort partially sent fragmented datagrams,
1531 * discard partially received fragmented datagrams
1532 */
1533static void fwnet_update(struct fw_unit *unit)
1534{
1535	struct fw_device *device = fw_parent_device(unit);
1536	struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1537	int generation;
1538
1539	generation = device->generation;
1540
1541	spin_lock_irq(&peer->dev->lock);
1542	peer->node_id    = device->node_id;
1543	peer->generation = generation;
1544	spin_unlock_irq(&peer->dev->lock);
1545}
1546
1547static void fwnet_remove_peer(struct fwnet_peer *peer, struct fwnet_device *dev)
1548{
1549	struct fwnet_partial_datagram *pd, *pd_next;
1550
1551	spin_lock_irq(&dev->lock);
1552	list_del(&peer->peer_link);
1553	dev->peer_count--;
1554	set_carrier_state(dev);
1555	spin_unlock_irq(&dev->lock);
1556
1557	list_for_each_entry_safe(pd, pd_next, &peer->pd_list, pd_link)
1558		fwnet_pd_delete(pd);
1559
1560	kfree(peer);
1561}
1562
1563static void fwnet_remove(struct fw_unit *unit)
1564{
1565	struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1566	struct fwnet_device *dev = peer->dev;
1567	struct net_device *net;
1568	int i;
1569
1570	mutex_lock(&fwnet_device_mutex);
1571
1572	net = dev->netdev;
1573
1574	fwnet_remove_peer(peer, dev);
1575
1576	if (list_empty(&dev->peer_list)) {
1577		unregister_netdev(net);
1578
1579		fwnet_fifo_stop(dev);
1580
1581		for (i = 0; dev->queued_datagrams && i < 5; i++)
1582			ssleep(1);
1583		WARN_ON(dev->queued_datagrams);
1584		list_del(&dev->dev_link);
1585
1586		free_netdev(net);
1587	}
1588
1589	mutex_unlock(&fwnet_device_mutex);
1590}
1591
1592static const struct ieee1394_device_id fwnet_id_table[] = {
1593	{
1594		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1595				IEEE1394_MATCH_VERSION,
1596		.specifier_id = IANA_SPECIFIER_ID,
1597		.version      = RFC2734_SW_VERSION,
1598	},
1599#if IS_ENABLED(CONFIG_IPV6)
1600	{
1601		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1602				IEEE1394_MATCH_VERSION,
1603		.specifier_id = IANA_SPECIFIER_ID,
1604		.version      = RFC3146_SW_VERSION,
1605	},
1606#endif
1607	{ }
1608};
1609
1610static struct fw_driver fwnet_driver = {
1611	.driver = {
1612		.owner  = THIS_MODULE,
1613		.name   = KBUILD_MODNAME,
1614		.bus    = &fw_bus_type,
1615	},
1616	.probe    = fwnet_probe,
1617	.update   = fwnet_update,
1618	.remove   = fwnet_remove,
1619	.id_table = fwnet_id_table,
1620};
1621
1622static const u32 rfc2374_unit_directory_data[] = {
1623	0x00040000,	/* directory_length		*/
1624	0x1200005e,	/* unit_specifier_id: IANA	*/
1625	0x81000003,	/* textual descriptor offset	*/
1626	0x13000001,	/* unit_sw_version: RFC 2734	*/
1627	0x81000005,	/* textual descriptor offset	*/
1628	0x00030000,	/* descriptor_length		*/
1629	0x00000000,	/* text				*/
1630	0x00000000,	/* minimal ASCII, en		*/
1631	0x49414e41,	/* I A N A			*/
1632	0x00030000,	/* descriptor_length		*/
1633	0x00000000,	/* text				*/
1634	0x00000000,	/* minimal ASCII, en		*/
1635	0x49507634,	/* I P v 4			*/
1636};
1637
1638static struct fw_descriptor rfc2374_unit_directory = {
1639	.length = ARRAY_SIZE(rfc2374_unit_directory_data),
1640	.key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1641	.data   = rfc2374_unit_directory_data
1642};
1643
1644#if IS_ENABLED(CONFIG_IPV6)
1645static const u32 rfc3146_unit_directory_data[] = {
1646	0x00040000,	/* directory_length		*/
1647	0x1200005e,	/* unit_specifier_id: IANA	*/
1648	0x81000003,	/* textual descriptor offset	*/
1649	0x13000002,	/* unit_sw_version: RFC 3146	*/
1650	0x81000005,	/* textual descriptor offset	*/
1651	0x00030000,	/* descriptor_length		*/
1652	0x00000000,	/* text				*/
1653	0x00000000,	/* minimal ASCII, en		*/
1654	0x49414e41,	/* I A N A			*/
1655	0x00030000,	/* descriptor_length		*/
1656	0x00000000,	/* text				*/
1657	0x00000000,	/* minimal ASCII, en		*/
1658	0x49507636,	/* I P v 6			*/
1659};
1660
1661static struct fw_descriptor rfc3146_unit_directory = {
1662	.length = ARRAY_SIZE(rfc3146_unit_directory_data),
1663	.key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1664	.data   = rfc3146_unit_directory_data
1665};
1666#endif
1667
1668static int __init fwnet_init(void)
1669{
1670	int err;
1671
1672	err = fw_core_add_descriptor(&rfc2374_unit_directory);
1673	if (err)
1674		return err;
1675
1676#if IS_ENABLED(CONFIG_IPV6)
1677	err = fw_core_add_descriptor(&rfc3146_unit_directory);
1678	if (err)
1679		goto out;
1680#endif
1681
1682	fwnet_packet_task_cache = kmem_cache_create("packet_task",
1683			sizeof(struct fwnet_packet_task), 0, 0, NULL);
1684	if (!fwnet_packet_task_cache) {
1685		err = -ENOMEM;
1686		goto out2;
1687	}
1688
1689	err = driver_register(&fwnet_driver.driver);
1690	if (!err)
1691		return 0;
1692
1693	kmem_cache_destroy(fwnet_packet_task_cache);
1694out2:
1695#if IS_ENABLED(CONFIG_IPV6)
1696	fw_core_remove_descriptor(&rfc3146_unit_directory);
1697out:
1698#endif
1699	fw_core_remove_descriptor(&rfc2374_unit_directory);
1700
1701	return err;
1702}
1703module_init(fwnet_init);
1704
1705static void __exit fwnet_cleanup(void)
1706{
1707	driver_unregister(&fwnet_driver.driver);
1708	kmem_cache_destroy(fwnet_packet_task_cache);
1709#if IS_ENABLED(CONFIG_IPV6)
1710	fw_core_remove_descriptor(&rfc3146_unit_directory);
1711#endif
1712	fw_core_remove_descriptor(&rfc2374_unit_directory);
1713}
1714module_exit(fwnet_cleanup);
1715
1716MODULE_AUTHOR("Jay Fenlason <fenlason@redhat.com>");
1717MODULE_DESCRIPTION("IP over IEEE1394 as per RFC 2734/3146");
1718MODULE_LICENSE("GPL");
1719MODULE_DEVICE_TABLE(ieee1394, fwnet_id_table);
1720