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v6.13.7
   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 <linux/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);
v5.14.15
   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);