net.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * IPv4 over IEEE 1394, per RFC 2734
   4 * IPv6 over IEEE 1394, per RFC 3146
   5 *
   6 * Copyright (C) 2009 Jay Fenlason <fenlason@redhat.com>
   7 *
   8 * based on eth1394 by Ben Collins et al
   9 */
  10
  11#include <linux/bug.h>
  12#include <linux/compiler.h>
  13#include <linux/delay.h>
  14#include <linux/device.h>
  15#include <linux/ethtool.h>
  16#include <linux/firewire.h>
  17#include <linux/firewire-constants.h>
  18#include <linux/highmem.h>
  19#include <linux/in.h>
  20#include <linux/ip.h>
  21#include <linux/jiffies.h>
  22#include <linux/mod_devicetable.h>
  23#include <linux/module.h>
  24#include <linux/moduleparam.h>
  25#include <linux/mutex.h>
  26#include <linux/netdevice.h>
  27#include <linux/skbuff.h>
  28#include <linux/slab.h>
  29#include <linux/spinlock.h>
  30
  31#include <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, const struct net_device *dev,
 261			      unsigned char *haddr)
 262{
 263	memcpy(haddr, dev->dev_addr, FWNET_ALEN);
 264
 265	return FWNET_ALEN;
 266}
 267
 268static const struct header_ops fwnet_header_ops = {
 269	.create         = fwnet_header_create,
 270	.cache		= fwnet_header_cache,
 271	.cache_update	= fwnet_header_cache_update,
 272	.parse          = fwnet_header_parse,
 273};
 274
 275/* FIXME: is this correct for all cases? */
 276static bool fwnet_frag_overlap(struct fwnet_partial_datagram *pd,
 277			       unsigned offset, unsigned len)
 278{
 279	struct fwnet_fragment_info *fi;
 280	unsigned end = offset + len;
 281
 282	list_for_each_entry(fi, &pd->fi_list, fi_link)
 283		if (offset < fi->offset + fi->len && end > fi->offset)
 284			return true;
 285
 286	return false;
 287}
 288
 289/* Assumes that new fragment does not overlap any existing fragments */
 290static struct fwnet_fragment_info *fwnet_frag_new(
 291	struct fwnet_partial_datagram *pd, unsigned offset, unsigned len)
 292{
 293	struct fwnet_fragment_info *fi, *fi2, *new;
 294	struct list_head *list;
 295
 296	list = &pd->fi_list;
 297	list_for_each_entry(fi, &pd->fi_list, fi_link) {
 298		if (fi->offset + fi->len == offset) {
 299			/* The new fragment can be tacked on to the end */
 300			/* Did the new fragment plug a hole? */
 301			fi2 = list_entry(fi->fi_link.next,
 302					 struct fwnet_fragment_info, fi_link);
 303			if (fi->offset + fi->len == fi2->offset) {
 304				/* glue fragments together */
 305				fi->len += len + fi2->len;
 306				list_del(&fi2->fi_link);
 307				kfree(fi2);
 308			} else {
 309				fi->len += len;
 310			}
 311
 312			return fi;
 313		}
 314		if (offset + len == fi->offset) {
 315			/* The new fragment can be tacked on to the beginning */
 316			/* Did the new fragment plug a hole? */
 317			fi2 = list_entry(fi->fi_link.prev,
 318					 struct fwnet_fragment_info, fi_link);
 319			if (fi2->offset + fi2->len == fi->offset) {
 320				/* glue fragments together */
 321				fi2->len += fi->len + len;
 322				list_del(&fi->fi_link);
 323				kfree(fi);
 324
 325				return fi2;
 326			}
 327			fi->offset = offset;
 328			fi->len += len;
 329
 330			return fi;
 331		}
 332		if (offset > fi->offset + fi->len) {
 333			list = &fi->fi_link;
 334			break;
 335		}
 336		if (offset + len < fi->offset) {
 337			list = fi->fi_link.prev;
 338			break;
 339		}
 340	}
 341
 342	new = kmalloc(sizeof(*new), GFP_ATOMIC);
 343	if (!new)
 344		return NULL;
 345
 346	new->offset = offset;
 347	new->len = len;
 348	list_add(&new->fi_link, list);
 349
 350	return new;
 351}
 352
 353static struct fwnet_partial_datagram *fwnet_pd_new(struct net_device *net,
 354		struct fwnet_peer *peer, u16 datagram_label, unsigned dg_size,
 355		void *frag_buf, unsigned frag_off, unsigned frag_len)
 356{
 357	struct fwnet_partial_datagram *new;
 358	struct fwnet_fragment_info *fi;
 359
 360	new = kmalloc(sizeof(*new), GFP_ATOMIC);
 361	if (!new)
 362		goto fail;
 363
 364	INIT_LIST_HEAD(&new->fi_list);
 365	fi = fwnet_frag_new(new, frag_off, frag_len);
 366	if (fi == NULL)
 367		goto fail_w_new;
 368
 369	new->datagram_label = datagram_label;
 370	new->datagram_size = dg_size;
 371	new->skb = dev_alloc_skb(dg_size + LL_RESERVED_SPACE(net));
 372	if (new->skb == NULL)
 373		goto fail_w_fi;
 374
 375	skb_reserve(new->skb, LL_RESERVED_SPACE(net));
 376	new->pbuf = skb_put(new->skb, dg_size);
 377	memcpy(new->pbuf + frag_off, frag_buf, frag_len);
 378	list_add_tail(&new->pd_link, &peer->pd_list);
 379
 380	return new;
 381
 382fail_w_fi:
 383	kfree(fi);
 384fail_w_new:
 385	kfree(new);
 386fail:
 387	return NULL;
 388}
 389
 390static struct fwnet_partial_datagram *fwnet_pd_find(struct fwnet_peer *peer,
 391						    u16 datagram_label)
 392{
 393	struct fwnet_partial_datagram *pd;
 394
 395	list_for_each_entry(pd, &peer->pd_list, pd_link)
 396		if (pd->datagram_label == datagram_label)
 397			return pd;
 398
 399	return NULL;
 400}
 401
 402
 403static void fwnet_pd_delete(struct fwnet_partial_datagram *old)
 404{
 405	struct fwnet_fragment_info *fi, *n;
 406
 407	list_for_each_entry_safe(fi, n, &old->fi_list, fi_link)
 408		kfree(fi);
 409
 410	list_del(&old->pd_link);
 411	dev_kfree_skb_any(old->skb);
 412	kfree(old);
 413}
 414
 415static bool fwnet_pd_update(struct fwnet_peer *peer,
 416		struct fwnet_partial_datagram *pd, void *frag_buf,
 417		unsigned frag_off, unsigned frag_len)
 418{
 419	if (fwnet_frag_new(pd, frag_off, frag_len) == NULL)
 420		return false;
 421
 422	memcpy(pd->pbuf + frag_off, frag_buf, frag_len);
 423
 424	/*
 425	 * Move list entry to beginning of list so that oldest partial
 426	 * datagrams percolate to the end of the list
 427	 */
 428	list_move_tail(&pd->pd_link, &peer->pd_list);
 429
 430	return true;
 431}
 432
 433static bool fwnet_pd_is_complete(struct fwnet_partial_datagram *pd)
 434{
 435	struct fwnet_fragment_info *fi;
 436
 437	fi = list_entry(pd->fi_list.next, struct fwnet_fragment_info, fi_link);
 438
 439	return fi->len == pd->datagram_size;
 440}
 441
 442/* caller must hold dev->lock */
 443static struct fwnet_peer *fwnet_peer_find_by_guid(struct fwnet_device *dev,
 444						  u64 guid)
 445{
 446	struct fwnet_peer *peer;
 447
 448	list_for_each_entry(peer, &dev->peer_list, peer_link)
 449		if (peer->guid == guid)
 450			return peer;
 451
 452	return NULL;
 453}
 454
 455/* caller must hold dev->lock */
 456static struct fwnet_peer *fwnet_peer_find_by_node_id(struct fwnet_device *dev,
 457						int node_id, int generation)
 458{
 459	struct fwnet_peer *peer;
 460
 461	list_for_each_entry(peer, &dev->peer_list, peer_link)
 462		if (peer->node_id    == node_id &&
 463		    peer->generation == generation)
 464			return peer;
 465
 466	return NULL;
 467}
 468
 469/* See IEEE 1394-2008 table 6-4, table 8-8, table 16-18. */
 470static unsigned fwnet_max_payload(unsigned max_rec, unsigned speed)
 471{
 472	max_rec = min(max_rec, speed + 8);
 473	max_rec = clamp(max_rec, 8U, 11U); /* 512...4096 */
 474
 475	return (1 << (max_rec + 1)) - RFC2374_FRAG_HDR_SIZE;
 476}
 477
 478
 479static int fwnet_finish_incoming_packet(struct net_device *net,
 480					struct sk_buff *skb, u16 source_node_id,
 481					bool is_broadcast, u16 ether_type)
 482{
 483	int status, len;
 484
 485	switch (ether_type) {
 486	case ETH_P_ARP:
 487	case ETH_P_IP:
 488#if IS_ENABLED(CONFIG_IPV6)
 489	case ETH_P_IPV6:
 490#endif
 491		break;
 492	default:
 493		goto err;
 494	}
 495
 496	/* Write metadata, and then pass to the receive level */
 497	skb->dev = net;
 498	skb->ip_summed = CHECKSUM_NONE;
 499
 500	/*
 501	 * Parse the encapsulation header. This actually does the job of
 502	 * converting to an ethernet-like pseudo frame header.
 503	 */
 504	if (dev_hard_header(skb, net, ether_type,
 505			   is_broadcast ? net->broadcast : net->dev_addr,
 506			   NULL, skb->len) >= 0) {
 507		struct fwnet_header *eth;
 508		u16 *rawp;
 509		__be16 protocol;
 510
 511		skb_reset_mac_header(skb);
 512		skb_pull(skb, sizeof(*eth));
 513		eth = (struct fwnet_header *)skb_mac_header(skb);
 514		if (fwnet_hwaddr_is_multicast(eth->h_dest)) {
 515			if (memcmp(eth->h_dest, net->broadcast,
 516				   net->addr_len) == 0)
 517				skb->pkt_type = PACKET_BROADCAST;
 518#if 0
 519			else
 520				skb->pkt_type = PACKET_MULTICAST;
 521#endif
 522		} else {
 523			if (memcmp(eth->h_dest, net->dev_addr, net->addr_len))
 524				skb->pkt_type = PACKET_OTHERHOST;
 525		}
 526		if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN) {
 527			protocol = eth->h_proto;
 528		} else {
 529			rawp = (u16 *)skb->data;
 530			if (*rawp == 0xffff)
 531				protocol = htons(ETH_P_802_3);
 532			else
 533				protocol = htons(ETH_P_802_2);
 534		}
 535		skb->protocol = protocol;
 536	}
 537
 538	len = skb->len;
 539	status = netif_rx(skb);
 540	if (status == NET_RX_DROP) {
 541		net->stats.rx_errors++;
 542		net->stats.rx_dropped++;
 543	} else {
 544		net->stats.rx_packets++;
 545		net->stats.rx_bytes += len;
 546	}
 547
 548	return 0;
 549
 550 err:
 551	net->stats.rx_errors++;
 552	net->stats.rx_dropped++;
 553
 554	dev_kfree_skb_any(skb);
 555
 556	return -ENOENT;
 557}
 558
 559static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
 560				 int source_node_id, int generation,
 561				 bool is_broadcast)
 562{
 563	struct sk_buff *skb;
 564	struct net_device *net = dev->netdev;
 565	struct rfc2734_header hdr;
 566	unsigned lf;
 567	unsigned long flags;
 568	struct fwnet_peer *peer;
 569	struct fwnet_partial_datagram *pd;
 570	int fg_off;
 571	int dg_size;
 572	u16 datagram_label;
 573	int retval;
 574	u16 ether_type;
 575
 576	if (len <= RFC2374_UNFRAG_HDR_SIZE)
 577		return 0;
 578
 579	hdr.w0 = be32_to_cpu(buf[0]);
 580	lf = fwnet_get_hdr_lf(&hdr);
 581	if (lf == RFC2374_HDR_UNFRAG) {
 582		/*
 583		 * An unfragmented datagram has been received by the ieee1394
 584		 * bus. Build an skbuff around it so we can pass it to the
 585		 * high level network layer.
 586		 */
 587		ether_type = fwnet_get_hdr_ether_type(&hdr);
 588		buf++;
 589		len -= RFC2374_UNFRAG_HDR_SIZE;
 590
 591		skb = dev_alloc_skb(len + LL_RESERVED_SPACE(net));
 592		if (unlikely(!skb)) {
 593			net->stats.rx_dropped++;
 594
 595			return -ENOMEM;
 596		}
 597		skb_reserve(skb, LL_RESERVED_SPACE(net));
 598		skb_put_data(skb, buf, len);
 599
 600		return fwnet_finish_incoming_packet(net, skb, source_node_id,
 601						    is_broadcast, ether_type);
 602	}
 603
 604	/* A datagram fragment has been received, now the fun begins. */
 605
 606	if (len <= RFC2374_FRAG_HDR_SIZE)
 607		return 0;
 608
 609	hdr.w1 = ntohl(buf[1]);
 610	buf += 2;
 611	len -= RFC2374_FRAG_HDR_SIZE;
 612	if (lf == RFC2374_HDR_FIRSTFRAG) {
 613		ether_type = fwnet_get_hdr_ether_type(&hdr);
 614		fg_off = 0;
 615	} else {
 616		ether_type = 0;
 617		fg_off = fwnet_get_hdr_fg_off(&hdr);
 618	}
 619	datagram_label = fwnet_get_hdr_dgl(&hdr);
 620	dg_size = fwnet_get_hdr_dg_size(&hdr);
 621
 622	if (fg_off + len > dg_size)
 623		return 0;
 624
 625	spin_lock_irqsave(&dev->lock, flags);
 626
 627	peer = fwnet_peer_find_by_node_id(dev, source_node_id, generation);
 628	if (!peer) {
 629		retval = -ENOENT;
 630		goto fail;
 631	}
 632
 633	pd = fwnet_pd_find(peer, datagram_label);
 634	if (pd == NULL) {
 635		while (peer->pdg_size >= FWNET_MAX_FRAGMENTS) {
 636			/* remove the oldest */
 637			fwnet_pd_delete(list_first_entry(&peer->pd_list,
 638				struct fwnet_partial_datagram, pd_link));
 639			peer->pdg_size--;
 640		}
 641		pd = fwnet_pd_new(net, peer, datagram_label,
 642				  dg_size, buf, fg_off, len);
 643		if (pd == NULL) {
 644			retval = -ENOMEM;
 645			goto fail;
 646		}
 647		peer->pdg_size++;
 648	} else {
 649		if (fwnet_frag_overlap(pd, fg_off, len) ||
 650		    pd->datagram_size != dg_size) {
 651			/*
 652			 * Differing datagram sizes or overlapping fragments,
 653			 * discard old datagram and start a new one.
 654			 */
 655			fwnet_pd_delete(pd);
 656			pd = fwnet_pd_new(net, peer, datagram_label,
 657					  dg_size, buf, fg_off, len);
 658			if (pd == NULL) {
 659				peer->pdg_size--;
 660				retval = -ENOMEM;
 661				goto fail;
 662			}
 663		} else {
 664			if (!fwnet_pd_update(peer, pd, buf, fg_off, len)) {
 665				/*
 666				 * Couldn't save off fragment anyway
 667				 * so might as well obliterate the
 668				 * datagram now.
 669				 */
 670				fwnet_pd_delete(pd);
 671				peer->pdg_size--;
 672				retval = -ENOMEM;
 673				goto fail;
 674			}
 675		}
 676	} /* new datagram or add to existing one */
 677
 678	if (lf == RFC2374_HDR_FIRSTFRAG)
 679		pd->ether_type = ether_type;
 680
 681	if (fwnet_pd_is_complete(pd)) {
 682		ether_type = pd->ether_type;
 683		peer->pdg_size--;
 684		skb = skb_get(pd->skb);
 685		fwnet_pd_delete(pd);
 686
 687		spin_unlock_irqrestore(&dev->lock, flags);
 688
 689		return fwnet_finish_incoming_packet(net, skb, source_node_id,
 690						    false, ether_type);
 691	}
 692	/*
 693	 * Datagram is not complete, we're done for the
 694	 * moment.
 695	 */
 696	retval = 0;
 697 fail:
 698	spin_unlock_irqrestore(&dev->lock, flags);
 699
 700	return retval;
 701}
 702
 703static void fwnet_receive_packet(struct fw_card *card, struct fw_request *r,
 704		int tcode, int destination, int source, int generation,
 705		unsigned long long offset, void *payload, size_t length,
 706		void *callback_data)
 707{
 708	struct fwnet_device *dev = callback_data;
 709	int rcode;
 710
 711	if (destination == IEEE1394_ALL_NODES) {
 712		// Although the response to the broadcast packet is not necessarily required, the
 713		// fw_send_response() function should still be called to maintain the reference
 714		// counting of the object. In the case, the call of function just releases the
 715		// object as a result to decrease the reference counting.
 716		rcode = RCODE_COMPLETE;
 717	} else if (offset != dev->handler.offset) {
 718		rcode = RCODE_ADDRESS_ERROR;
 719	} else if (tcode != TCODE_WRITE_BLOCK_REQUEST) {
 720		rcode = RCODE_TYPE_ERROR;
 721	} else if (fwnet_incoming_packet(dev, payload, length,
 722					 source, generation, false) != 0) {
 723		dev_err(&dev->netdev->dev, "incoming packet failure\n");
 724		rcode = RCODE_CONFLICT_ERROR;
 725	} else {
 726		rcode = RCODE_COMPLETE;
 727	}
 728
 729	fw_send_response(card, r, rcode);
 730}
 731
 732static int gasp_source_id(__be32 *p)
 733{
 734	return be32_to_cpu(p[0]) >> 16;
 735}
 736
 737static u32 gasp_specifier_id(__be32 *p)
 738{
 739	return (be32_to_cpu(p[0]) & 0xffff) << 8 |
 740	       (be32_to_cpu(p[1]) & 0xff000000) >> 24;
 741}
 742
 743static u32 gasp_version(__be32 *p)
 744{
 745	return be32_to_cpu(p[1]) & 0xffffff;
 746}
 747
 748static void fwnet_receive_broadcast(struct fw_iso_context *context,
 749		u32 cycle, size_t header_length, void *header, void *data)
 750{
 751	struct fwnet_device *dev;
 752	struct fw_iso_packet packet;
 753	__be16 *hdr_ptr;
 754	__be32 *buf_ptr;
 755	int retval;
 756	u32 length;
 757	unsigned long offset;
 758	unsigned long flags;
 759
 760	dev = data;
 761	hdr_ptr = header;
 762	length = be16_to_cpup(hdr_ptr);
 763
 764	spin_lock_irqsave(&dev->lock, flags);
 765
 766	offset = dev->rcv_buffer_size * dev->broadcast_rcv_next_ptr;
 767	buf_ptr = dev->broadcast_rcv_buffer_ptrs[dev->broadcast_rcv_next_ptr++];
 768	if (dev->broadcast_rcv_next_ptr == dev->num_broadcast_rcv_ptrs)
 769		dev->broadcast_rcv_next_ptr = 0;
 770
 771	spin_unlock_irqrestore(&dev->lock, flags);
 772
 773	if (length > IEEE1394_GASP_HDR_SIZE &&
 774	    gasp_specifier_id(buf_ptr) == IANA_SPECIFIER_ID &&
 775	    (gasp_version(buf_ptr) == RFC2734_SW_VERSION
 776#if IS_ENABLED(CONFIG_IPV6)
 777	     || gasp_version(buf_ptr) == RFC3146_SW_VERSION
 778#endif
 779	    ))
 780		fwnet_incoming_packet(dev, buf_ptr + 2,
 781				      length - IEEE1394_GASP_HDR_SIZE,
 782				      gasp_source_id(buf_ptr),
 783				      context->card->generation, true);
 784
 785	packet.payload_length = dev->rcv_buffer_size;
 786	packet.interrupt = 1;
 787	packet.skip = 0;
 788	packet.tag = 3;
 789	packet.sy = 0;
 790	packet.header_length = IEEE1394_GASP_HDR_SIZE;
 791
 792	spin_lock_irqsave(&dev->lock, flags);
 793
 794	retval = fw_iso_context_queue(dev->broadcast_rcv_context, &packet,
 795				      &dev->broadcast_rcv_buffer, offset);
 796
 797	spin_unlock_irqrestore(&dev->lock, flags);
 798
 799	if (retval >= 0)
 800		fw_iso_context_queue_flush(dev->broadcast_rcv_context);
 801	else
 802		dev_err(&dev->netdev->dev, "requeue failed\n");
 803}
 804
 805static struct kmem_cache *fwnet_packet_task_cache;
 806
 807static void fwnet_free_ptask(struct fwnet_packet_task *ptask)
 808{
 809	dev_kfree_skb_any(ptask->skb);
 810	kmem_cache_free(fwnet_packet_task_cache, ptask);
 811}
 812
 813/* Caller must hold dev->lock. */
 814static void dec_queued_datagrams(struct fwnet_device *dev)
 815{
 816	if (--dev->queued_datagrams == FWNET_MIN_QUEUED_DATAGRAMS)
 817		netif_wake_queue(dev->netdev);
 818}
 819
 820static int fwnet_send_packet(struct fwnet_packet_task *ptask);
 821
 822static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
 823{
 824	struct fwnet_device *dev = ptask->dev;
 825	struct sk_buff *skb = ptask->skb;
 826	unsigned long flags;
 827	bool free;
 828
 829	spin_lock_irqsave(&dev->lock, flags);
 830
 831	ptask->outstanding_pkts--;
 832
 833	/* Check whether we or the networking TX soft-IRQ is last user. */
 834	free = (ptask->outstanding_pkts == 0 && ptask->enqueued);
 835	if (free)
 836		dec_queued_datagrams(dev);
 837
 838	if (ptask->outstanding_pkts == 0) {
 839		dev->netdev->stats.tx_packets++;
 840		dev->netdev->stats.tx_bytes += skb->len;
 841	}
 842
 843	spin_unlock_irqrestore(&dev->lock, flags);
 844
 845	if (ptask->outstanding_pkts > 0) {
 846		u16 dg_size;
 847		u16 fg_off;
 848		u16 datagram_label;
 849		u16 lf;
 850
 851		/* Update the ptask to point to the next fragment and send it */
 852		lf = fwnet_get_hdr_lf(&ptask->hdr);
 853		switch (lf) {
 854		case RFC2374_HDR_LASTFRAG:
 855		case RFC2374_HDR_UNFRAG:
 856		default:
 857			dev_err(&dev->netdev->dev,
 858				"outstanding packet %x lf %x, header %x,%x\n",
 859				ptask->outstanding_pkts, lf, ptask->hdr.w0,
 860				ptask->hdr.w1);
 861			BUG();
 862
 863		case RFC2374_HDR_FIRSTFRAG:
 864			/* Set frag type here for future interior fragments */
 865			dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
 866			fg_off = ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
 867			datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
 868			break;
 869
 870		case RFC2374_HDR_INTFRAG:
 871			dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
 872			fg_off = fwnet_get_hdr_fg_off(&ptask->hdr)
 873				  + ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
 874			datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
 875			break;
 876		}
 877
 878		if (ptask->dest_node == IEEE1394_ALL_NODES) {
 879			skb_pull(skb,
 880				 ptask->max_payload + IEEE1394_GASP_HDR_SIZE);
 881		} else {
 882			skb_pull(skb, ptask->max_payload);
 883		}
 884		if (ptask->outstanding_pkts > 1) {
 885			fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_INTFRAG,
 886					  dg_size, fg_off, datagram_label);
 887		} else {
 888			fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_LASTFRAG,
 889					  dg_size, fg_off, datagram_label);
 890			ptask->max_payload = skb->len + RFC2374_FRAG_HDR_SIZE;
 891		}
 892		fwnet_send_packet(ptask);
 893	}
 894
 895	if (free)
 896		fwnet_free_ptask(ptask);
 897}
 898
 899static void fwnet_transmit_packet_failed(struct fwnet_packet_task *ptask)
 900{
 901	struct fwnet_device *dev = ptask->dev;
 902	unsigned long flags;
 903	bool free;
 904
 905	spin_lock_irqsave(&dev->lock, flags);
 906
 907	/* One fragment failed; don't try to send remaining fragments. */
 908	ptask->outstanding_pkts = 0;
 909
 910	/* Check whether we or the networking TX soft-IRQ is last user. */
 911	free = ptask->enqueued;
 912	if (free)
 913		dec_queued_datagrams(dev);
 914
 915	dev->netdev->stats.tx_dropped++;
 916	dev->netdev->stats.tx_errors++;
 917
 918	spin_unlock_irqrestore(&dev->lock, flags);
 919
 920	if (free)
 921		fwnet_free_ptask(ptask);
 922}
 923
 924static void fwnet_write_complete(struct fw_card *card, int rcode,
 925				 void *payload, size_t length, void *data)
 926{
 927	struct fwnet_packet_task *ptask = data;
 928	static unsigned long j;
 929	static int last_rcode, errors_skipped;
 930
 931	if (rcode == RCODE_COMPLETE) {
 932		fwnet_transmit_packet_done(ptask);
 933	} else {
 934		if (printk_timed_ratelimit(&j,  1000) || rcode != last_rcode) {
 935			dev_err(&ptask->dev->netdev->dev,
 936				"fwnet_write_complete failed: %x (skipped %d)\n",
 937				rcode, errors_skipped);
 938
 939			errors_skipped = 0;
 940			last_rcode = rcode;
 941		} else {
 942			errors_skipped++;
 943		}
 944		fwnet_transmit_packet_failed(ptask);
 945	}
 946}
 947
 948static int fwnet_send_packet(struct fwnet_packet_task *ptask)
 949{
 950	struct fwnet_device *dev;
 951	unsigned tx_len;
 952	struct rfc2734_header *bufhdr;
 953	unsigned long flags;
 954	bool free;
 955
 956	dev = ptask->dev;
 957	tx_len = ptask->max_payload;
 958	switch (fwnet_get_hdr_lf(&ptask->hdr)) {
 959	case RFC2374_HDR_UNFRAG:
 960		bufhdr = skb_push(ptask->skb, RFC2374_UNFRAG_HDR_SIZE);
 961		put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
 962		break;
 963
 964	case RFC2374_HDR_FIRSTFRAG:
 965	case RFC2374_HDR_INTFRAG:
 966	case RFC2374_HDR_LASTFRAG:
 967		bufhdr = skb_push(ptask->skb, RFC2374_FRAG_HDR_SIZE);
 968		put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
 969		put_unaligned_be32(ptask->hdr.w1, &bufhdr->w1);
 970		break;
 971
 972	default:
 973		BUG();
 974	}
 975	if (ptask->dest_node == IEEE1394_ALL_NODES) {
 976		u8 *p;
 977		int generation;
 978		int node_id;
 979		unsigned int sw_version;
 980
 981		/* ptask->generation may not have been set yet */
 982		generation = dev->card->generation;
 983		smp_rmb();
 984		node_id = dev->card->node_id;
 985
 986		switch (ptask->skb->protocol) {
 987		default:
 988			sw_version = RFC2734_SW_VERSION;
 989			break;
 990#if IS_ENABLED(CONFIG_IPV6)
 991		case htons(ETH_P_IPV6):
 992			sw_version = RFC3146_SW_VERSION;
 993#endif
 994		}
 995
 996		p = skb_push(ptask->skb, IEEE1394_GASP_HDR_SIZE);
 997		put_unaligned_be32(node_id << 16 | IANA_SPECIFIER_ID >> 8, p);
 998		put_unaligned_be32((IANA_SPECIFIER_ID & 0xff) << 24
 999						| sw_version, &p[4]);
1000
1001		/* We should not transmit if broadcast_channel.valid == 0. */
1002		fw_send_request(dev->card, &ptask->transaction,
1003				TCODE_STREAM_DATA,
1004				fw_stream_packet_destination_id(3,
1005						IEEE1394_BROADCAST_CHANNEL, 0),
1006				generation, SCODE_100, 0ULL, ptask->skb->data,
1007				tx_len + 8, fwnet_write_complete, ptask);
1008
1009		spin_lock_irqsave(&dev->lock, flags);
1010
1011		/* If the AT work item already ran, we may be last user. */
1012		free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1013		if (!free)
1014			ptask->enqueued = true;
1015		else
1016			dec_queued_datagrams(dev);
1017
1018		spin_unlock_irqrestore(&dev->lock, flags);
1019
1020		goto out;
1021	}
1022
1023	fw_send_request(dev->card, &ptask->transaction,
1024			TCODE_WRITE_BLOCK_REQUEST, ptask->dest_node,
1025			ptask->generation, ptask->speed, ptask->fifo_addr,
1026			ptask->skb->data, tx_len, fwnet_write_complete, ptask);
1027
1028	spin_lock_irqsave(&dev->lock, flags);
1029
1030	/* If the AT work item already ran, we may be last user. */
1031	free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1032	if (!free)
1033		ptask->enqueued = true;
1034	else
1035		dec_queued_datagrams(dev);
1036
1037	spin_unlock_irqrestore(&dev->lock, flags);
1038
1039	netif_trans_update(dev->netdev);
1040 out:
1041	if (free)
1042		fwnet_free_ptask(ptask);
1043
1044	return 0;
1045}
1046
1047static void fwnet_fifo_stop(struct fwnet_device *dev)
1048{
1049	if (dev->local_fifo == FWNET_NO_FIFO_ADDR)
1050		return;
1051
1052	fw_core_remove_address_handler(&dev->handler);
1053	dev->local_fifo = FWNET_NO_FIFO_ADDR;
1054}
1055
1056static int fwnet_fifo_start(struct fwnet_device *dev)
1057{
1058	int retval;
1059
1060	if (dev->local_fifo != FWNET_NO_FIFO_ADDR)
1061		return 0;
1062
1063	dev->handler.length = 4096;
1064	dev->handler.address_callback = fwnet_receive_packet;
1065	dev->handler.callback_data = dev;
1066
1067	retval = fw_core_add_address_handler(&dev->handler,
1068					     &fw_high_memory_region);
1069	if (retval < 0)
1070		return retval;
1071
1072	dev->local_fifo = dev->handler.offset;
1073
1074	return 0;
1075}
1076
1077static void __fwnet_broadcast_stop(struct fwnet_device *dev)
1078{
1079	unsigned u;
1080
1081	if (dev->broadcast_state != FWNET_BROADCAST_ERROR) {
1082		for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++)
1083			kunmap(dev->broadcast_rcv_buffer.pages[u]);
1084		fw_iso_buffer_destroy(&dev->broadcast_rcv_buffer, dev->card);
1085	}
1086	if (dev->broadcast_rcv_context) {
1087		fw_iso_context_destroy(dev->broadcast_rcv_context);
1088		dev->broadcast_rcv_context = NULL;
1089	}
1090	kfree(dev->broadcast_rcv_buffer_ptrs);
1091	dev->broadcast_rcv_buffer_ptrs = NULL;
1092	dev->broadcast_state = FWNET_BROADCAST_ERROR;
1093}
1094
1095static void fwnet_broadcast_stop(struct fwnet_device *dev)
1096{
1097	if (dev->broadcast_state == FWNET_BROADCAST_ERROR)
1098		return;
1099	fw_iso_context_stop(dev->broadcast_rcv_context);
1100	__fwnet_broadcast_stop(dev);
1101}
1102
1103static int fwnet_broadcast_start(struct fwnet_device *dev)
1104{
1105	struct fw_iso_context *context;
1106	int retval;
1107	unsigned num_packets;
1108	unsigned max_receive;
1109	struct fw_iso_packet packet;
1110	unsigned long offset;
1111	void **ptrptr;
1112	unsigned u;
1113
1114	if (dev->broadcast_state != FWNET_BROADCAST_ERROR)
1115		return 0;
1116
1117	max_receive = 1U << (dev->card->max_receive + 1);
1118	num_packets = (FWNET_ISO_PAGE_COUNT * PAGE_SIZE) / max_receive;
1119
1120	ptrptr = kmalloc_array(num_packets, sizeof(void *), GFP_KERNEL);
1121	if (!ptrptr) {
1122		retval = -ENOMEM;
1123		goto failed;
1124	}
1125	dev->broadcast_rcv_buffer_ptrs = ptrptr;
1126
1127	context = fw_iso_context_create(dev->card, FW_ISO_CONTEXT_RECEIVE,
1128					IEEE1394_BROADCAST_CHANNEL,
1129					dev->card->link_speed, 8,
1130					fwnet_receive_broadcast, dev);
1131	if (IS_ERR(context)) {
1132		retval = PTR_ERR(context);
1133		goto failed;
1134	}
1135
1136	retval = fw_iso_buffer_init(&dev->broadcast_rcv_buffer, dev->card,
1137				    FWNET_ISO_PAGE_COUNT, DMA_FROM_DEVICE);
1138	if (retval < 0)
1139		goto failed;
1140
1141	dev->broadcast_state = FWNET_BROADCAST_STOPPED;
1142
1143	for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++) {
1144		void *ptr;
1145		unsigned v;
1146
1147		ptr = kmap(dev->broadcast_rcv_buffer.pages[u]);
1148		for (v = 0; v < num_packets / FWNET_ISO_PAGE_COUNT; v++)
1149			*ptrptr++ = (void *) ((char *)ptr + v * max_receive);
1150	}
1151	dev->broadcast_rcv_context = context;
1152
1153	packet.payload_length = max_receive;
1154	packet.interrupt = 1;
1155	packet.skip = 0;
1156	packet.tag = 3;
1157	packet.sy = 0;
1158	packet.header_length = IEEE1394_GASP_HDR_SIZE;
1159	offset = 0;
1160
1161	for (u = 0; u < num_packets; u++) {
1162		retval = fw_iso_context_queue(context, &packet,
1163				&dev->broadcast_rcv_buffer, offset);
1164		if (retval < 0)
1165			goto failed;
1166
1167		offset += max_receive;
1168	}
1169	dev->num_broadcast_rcv_ptrs = num_packets;
1170	dev->rcv_buffer_size = max_receive;
1171	dev->broadcast_rcv_next_ptr = 0U;
1172	retval = fw_iso_context_start(context, -1, 0,
1173			FW_ISO_CONTEXT_MATCH_ALL_TAGS); /* ??? sync */
1174	if (retval < 0)
1175		goto failed;
1176
1177	/* FIXME: adjust it according to the min. speed of all known peers? */
1178	dev->broadcast_xmt_max_payload = IEEE1394_MAX_PAYLOAD_S100
1179			- IEEE1394_GASP_HDR_SIZE - RFC2374_UNFRAG_HDR_SIZE;
1180	dev->broadcast_state = FWNET_BROADCAST_RUNNING;
1181
1182	return 0;
1183
1184 failed:
1185	__fwnet_broadcast_stop(dev);
1186	return retval;
1187}
1188
1189static void set_carrier_state(struct fwnet_device *dev)
1190{
1191	if (dev->peer_count > 1)
1192		netif_carrier_on(dev->netdev);
1193	else
1194		netif_carrier_off(dev->netdev);
1195}
1196
1197/* ifup */
1198static int fwnet_open(struct net_device *net)
1199{
1200	struct fwnet_device *dev = netdev_priv(net);
1201	int ret;
1202
1203	ret = fwnet_broadcast_start(dev);
1204	if (ret)
1205		return ret;
1206
1207	netif_start_queue(net);
1208
1209	spin_lock_irq(&dev->lock);
1210	set_carrier_state(dev);
1211	spin_unlock_irq(&dev->lock);
1212
1213	return 0;
1214}
1215
1216/* ifdown */
1217static int fwnet_stop(struct net_device *net)
1218{
1219	struct fwnet_device *dev = netdev_priv(net);
1220
1221	netif_stop_queue(net);
1222	fwnet_broadcast_stop(dev);
1223
1224	return 0;
1225}
1226
1227static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
1228{
1229	struct fwnet_header hdr_buf;
1230	struct fwnet_device *dev = netdev_priv(net);
1231	__be16 proto;
1232	u16 dest_node;
1233	unsigned max_payload;
1234	u16 dg_size;
1235	u16 *datagram_label_ptr;
1236	struct fwnet_packet_task *ptask;
1237	struct fwnet_peer *peer;
1238	unsigned long flags;
1239
1240	spin_lock_irqsave(&dev->lock, flags);
1241
1242	/* Can this happen? */
1243	if (netif_queue_stopped(dev->netdev)) {
1244		spin_unlock_irqrestore(&dev->lock, flags);
1245
1246		return NETDEV_TX_BUSY;
1247	}
1248
1249	ptask = kmem_cache_alloc(fwnet_packet_task_cache, GFP_ATOMIC);
1250	if (ptask == NULL)
1251		goto fail;
1252
1253	skb = skb_share_check(skb, GFP_ATOMIC);
1254	if (!skb)
1255		goto fail;
1256
1257	/*
1258	 * Make a copy of the driver-specific header.
1259	 * We might need to rebuild the header on tx failure.
1260	 */
1261	memcpy(&hdr_buf, skb->data, sizeof(hdr_buf));
1262	proto = hdr_buf.h_proto;
1263
1264	switch (proto) {
1265	case htons(ETH_P_ARP):
1266	case htons(ETH_P_IP):
1267#if IS_ENABLED(CONFIG_IPV6)
1268	case htons(ETH_P_IPV6):
1269#endif
1270		break;
1271	default:
1272		goto fail;
1273	}
1274
1275	skb_pull(skb, sizeof(hdr_buf));
1276	dg_size = skb->len;
1277
1278	/*
1279	 * Set the transmission type for the packet.  ARP packets and IP
1280	 * broadcast packets are sent via GASP.
1281	 */
1282	if (fwnet_hwaddr_is_multicast(hdr_buf.h_dest)) {
1283		max_payload        = dev->broadcast_xmt_max_payload;
1284		datagram_label_ptr = &dev->broadcast_xmt_datagramlabel;
1285
1286		ptask->fifo_addr   = FWNET_NO_FIFO_ADDR;
1287		ptask->generation  = 0;
1288		ptask->dest_node   = IEEE1394_ALL_NODES;
1289		ptask->speed       = SCODE_100;
1290	} else {
1291		union fwnet_hwaddr *ha = (union fwnet_hwaddr *)hdr_buf.h_dest;
1292		__be64 guid = get_unaligned(&ha->uc.uniq_id);
1293		u8 generation;
1294
1295		peer = fwnet_peer_find_by_guid(dev, be64_to_cpu(guid));
1296		if (!peer)
1297			goto fail;
1298
1299		generation         = peer->generation;
1300		dest_node          = peer->node_id;
1301		max_payload        = peer->max_payload;
1302		datagram_label_ptr = &peer->datagram_label;
1303
1304		ptask->fifo_addr   = get_unaligned_be48(ha->uc.fifo);
1305		ptask->generation  = generation;
1306		ptask->dest_node   = dest_node;
1307		ptask->speed       = peer->speed;
1308	}
1309
1310	ptask->hdr.w0 = 0;
1311	ptask->hdr.w1 = 0;
1312	ptask->skb = skb;
1313	ptask->dev = dev;
1314
1315	/* Does it all fit in one packet? */
1316	if (dg_size <= max_payload) {
1317		fwnet_make_uf_hdr(&ptask->hdr, ntohs(proto));
1318		ptask->outstanding_pkts = 1;
1319		max_payload = dg_size + RFC2374_UNFRAG_HDR_SIZE;
1320	} else {
1321		u16 datagram_label;
1322
1323		max_payload -= RFC2374_FRAG_OVERHEAD;
1324		datagram_label = (*datagram_label_ptr)++;
1325		fwnet_make_ff_hdr(&ptask->hdr, ntohs(proto), dg_size,
1326				  datagram_label);
1327		ptask->outstanding_pkts = DIV_ROUND_UP(dg_size, max_payload);
1328		max_payload += RFC2374_FRAG_HDR_SIZE;
1329	}
1330
1331	if (++dev->queued_datagrams == FWNET_MAX_QUEUED_DATAGRAMS)
1332		netif_stop_queue(dev->netdev);
1333
1334	spin_unlock_irqrestore(&dev->lock, flags);
1335
1336	ptask->max_payload = max_payload;
1337	ptask->enqueued    = 0;
1338
1339	fwnet_send_packet(ptask);
1340
1341	return NETDEV_TX_OK;
1342
1343 fail:
1344	spin_unlock_irqrestore(&dev->lock, flags);
1345
1346	if (ptask)
1347		kmem_cache_free(fwnet_packet_task_cache, ptask);
1348
1349	if (skb != NULL)
1350		dev_kfree_skb(skb);
1351
1352	net->stats.tx_dropped++;
1353	net->stats.tx_errors++;
1354
1355	/*
1356	 * FIXME: According to a patch from 2003-02-26, "returning non-zero
1357	 * causes serious problems" here, allegedly.  Before that patch,
1358	 * -ERRNO was returned which is not appropriate under Linux 2.6.
1359	 * Perhaps more needs to be done?  Stop the queue in serious
1360	 * conditions and restart it elsewhere?
1361	 */
1362	return NETDEV_TX_OK;
1363}
1364
1365static const struct ethtool_ops fwnet_ethtool_ops = {
1366	.get_link	= ethtool_op_get_link,
1367};
1368
1369static const struct net_device_ops fwnet_netdev_ops = {
1370	.ndo_open       = fwnet_open,
1371	.ndo_stop	= fwnet_stop,
1372	.ndo_start_xmit = fwnet_tx,
1373};
1374
1375static void fwnet_init_dev(struct net_device *net)
1376{
1377	net->header_ops		= &fwnet_header_ops;
1378	net->netdev_ops		= &fwnet_netdev_ops;
1379	net->watchdog_timeo	= 2 * HZ;
1380	net->flags		= IFF_BROADCAST | IFF_MULTICAST;
1381	net->features		= NETIF_F_HIGHDMA;
1382	net->addr_len		= FWNET_ALEN;
1383	net->hard_header_len	= FWNET_HLEN;
1384	net->type		= ARPHRD_IEEE1394;
1385	net->tx_queue_len	= FWNET_TX_QUEUE_LEN;
1386	net->ethtool_ops	= &fwnet_ethtool_ops;
1387}
1388
1389/* caller must hold fwnet_device_mutex */
1390static struct fwnet_device *fwnet_dev_find(struct fw_card *card)
1391{
1392	struct fwnet_device *dev;
1393
1394	list_for_each_entry(dev, &fwnet_device_list, dev_link)
1395		if (dev->card == card)
1396			return dev;
1397
1398	return NULL;
1399}
1400
1401static int fwnet_add_peer(struct fwnet_device *dev,
1402			  struct fw_unit *unit, struct fw_device *device)
1403{
1404	struct fwnet_peer *peer;
1405
1406	peer = kmalloc(sizeof(*peer), GFP_KERNEL);
1407	if (!peer)
1408		return -ENOMEM;
1409
1410	dev_set_drvdata(&unit->device, peer);
1411
1412	peer->dev = dev;
1413	peer->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1414	INIT_LIST_HEAD(&peer->pd_list);
1415	peer->pdg_size = 0;
1416	peer->datagram_label = 0;
1417	peer->speed = device->max_speed;
1418	peer->max_payload = fwnet_max_payload(device->max_rec, peer->speed);
1419
1420	peer->generation = device->generation;
1421	smp_rmb();
1422	peer->node_id = device->node_id;
1423
1424	spin_lock_irq(&dev->lock);
1425	list_add_tail(&peer->peer_link, &dev->peer_list);
1426	dev->peer_count++;
1427	set_carrier_state(dev);
1428	spin_unlock_irq(&dev->lock);
1429
1430	return 0;
1431}
1432
1433static int fwnet_probe(struct fw_unit *unit,
1434		       const struct ieee1394_device_id *id)
1435{
1436	struct fw_device *device = fw_parent_device(unit);
1437	struct fw_card *card = device->card;
1438	struct net_device *net;
1439	bool allocated_netdev = false;
1440	struct fwnet_device *dev;
1441	union fwnet_hwaddr ha;
1442	int ret;
1443
1444	mutex_lock(&fwnet_device_mutex);
1445
1446	dev = fwnet_dev_find(card);
1447	if (dev) {
1448		net = dev->netdev;
1449		goto have_dev;
1450	}
1451
1452	net = alloc_netdev(sizeof(*dev), "firewire%d", NET_NAME_UNKNOWN,
1453			   fwnet_init_dev);
1454	if (net == NULL) {
1455		mutex_unlock(&fwnet_device_mutex);
1456		return -ENOMEM;
1457	}
1458
1459	allocated_netdev = true;
1460	SET_NETDEV_DEV(net, card->device);
1461	dev = netdev_priv(net);
1462
1463	spin_lock_init(&dev->lock);
1464	dev->broadcast_state = FWNET_BROADCAST_ERROR;
1465	dev->broadcast_rcv_context = NULL;
1466	dev->broadcast_xmt_max_payload = 0;
1467	dev->broadcast_xmt_datagramlabel = 0;
1468	dev->local_fifo = FWNET_NO_FIFO_ADDR;
1469	dev->queued_datagrams = 0;
1470	INIT_LIST_HEAD(&dev->peer_list);
1471	dev->card = card;
1472	dev->netdev = net;
1473
1474	ret = fwnet_fifo_start(dev);
1475	if (ret < 0)
1476		goto out;
1477	dev->local_fifo = dev->handler.offset;
1478
1479	/*
1480	 * default MTU: RFC 2734 cl. 4, RFC 3146 cl. 4
1481	 * maximum MTU: RFC 2734 cl. 4.2, fragment encapsulation header's
1482	 *              maximum possible datagram_size + 1 = 0xfff + 1
1483	 */
1484	net->mtu = 1500U;
1485	net->min_mtu = ETH_MIN_MTU;
1486	net->max_mtu = 4096U;
1487
1488	/* Set our hardware address while we're at it */
1489	ha.uc.uniq_id = cpu_to_be64(card->guid);
1490	ha.uc.max_rec = dev->card->max_receive;
1491	ha.uc.sspd = dev->card->link_speed;
1492	put_unaligned_be48(dev->local_fifo, ha.uc.fifo);
1493	dev_addr_set(net, ha.u);
1494
1495	memset(net->broadcast, -1, net->addr_len);
1496
1497	ret = register_netdev(net);
1498	if (ret)
1499		goto out;
1500
1501	list_add_tail(&dev->dev_link, &fwnet_device_list);
1502	dev_notice(&net->dev, "IP over IEEE 1394 on card %s\n",
1503		   dev_name(card->device));
1504 have_dev:
1505	ret = fwnet_add_peer(dev, unit, device);
1506	if (ret && allocated_netdev) {
1507		unregister_netdev(net);
1508		list_del(&dev->dev_link);
1509 out:
1510		fwnet_fifo_stop(dev);
1511		free_netdev(net);
1512	}
1513
1514	mutex_unlock(&fwnet_device_mutex);
1515
1516	return ret;
1517}
1518
1519/*
1520 * FIXME abort partially sent fragmented datagrams,
1521 * discard partially received fragmented datagrams
1522 */
1523static void fwnet_update(struct fw_unit *unit)
1524{
1525	struct fw_device *device = fw_parent_device(unit);
1526	struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1527	int generation;
1528
1529	generation = device->generation;
1530
1531	spin_lock_irq(&peer->dev->lock);
1532	peer->node_id    = device->node_id;
1533	peer->generation = generation;
1534	spin_unlock_irq(&peer->dev->lock);
1535}
1536
1537static void fwnet_remove_peer(struct fwnet_peer *peer, struct fwnet_device *dev)
1538{
1539	struct fwnet_partial_datagram *pd, *pd_next;
1540
1541	spin_lock_irq(&dev->lock);
1542	list_del(&peer->peer_link);
1543	dev->peer_count--;
1544	set_carrier_state(dev);
1545	spin_unlock_irq(&dev->lock);
1546
1547	list_for_each_entry_safe(pd, pd_next, &peer->pd_list, pd_link)
1548		fwnet_pd_delete(pd);
1549
1550	kfree(peer);
1551}
1552
1553static void fwnet_remove(struct fw_unit *unit)
1554{
1555	struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1556	struct fwnet_device *dev = peer->dev;
1557	struct net_device *net;
1558	int i;
1559
1560	mutex_lock(&fwnet_device_mutex);
1561
1562	net = dev->netdev;
1563
1564	fwnet_remove_peer(peer, dev);
1565
1566	if (list_empty(&dev->peer_list)) {
1567		unregister_netdev(net);
1568
1569		fwnet_fifo_stop(dev);
1570
1571		for (i = 0; dev->queued_datagrams && i < 5; i++)
1572			ssleep(1);
1573		WARN_ON(dev->queued_datagrams);
1574		list_del(&dev->dev_link);
1575
1576		free_netdev(net);
1577	}
1578
1579	mutex_unlock(&fwnet_device_mutex);
1580}
1581
1582static const struct ieee1394_device_id fwnet_id_table[] = {
1583	{
1584		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1585				IEEE1394_MATCH_VERSION,
1586		.specifier_id = IANA_SPECIFIER_ID,
1587		.version      = RFC2734_SW_VERSION,
1588	},
1589#if IS_ENABLED(CONFIG_IPV6)
1590	{
1591		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1592				IEEE1394_MATCH_VERSION,
1593		.specifier_id = IANA_SPECIFIER_ID,
1594		.version      = RFC3146_SW_VERSION,
1595	},
1596#endif
1597	{ }
1598};
1599
1600static struct fw_driver fwnet_driver = {
1601	.driver = {
1602		.owner  = THIS_MODULE,
1603		.name   = KBUILD_MODNAME,
1604		.bus    = &fw_bus_type,
1605	},
1606	.probe    = fwnet_probe,
1607	.update   = fwnet_update,
1608	.remove   = fwnet_remove,
1609	.id_table = fwnet_id_table,
1610};
1611
1612static const u32 rfc2374_unit_directory_data[] = {
1613	0x00040000,	/* directory_length		*/
1614	0x1200005e,	/* unit_specifier_id: IANA	*/
1615	0x81000003,	/* textual descriptor offset	*/
1616	0x13000001,	/* unit_sw_version: RFC 2734	*/
1617	0x81000005,	/* textual descriptor offset	*/
1618	0x00030000,	/* descriptor_length		*/
1619	0x00000000,	/* text				*/
1620	0x00000000,	/* minimal ASCII, en		*/
1621	0x49414e41,	/* I A N A			*/
1622	0x00030000,	/* descriptor_length		*/
1623	0x00000000,	/* text				*/
1624	0x00000000,	/* minimal ASCII, en		*/
1625	0x49507634,	/* I P v 4			*/
1626};
1627
1628static struct fw_descriptor rfc2374_unit_directory = {
1629	.length = ARRAY_SIZE(rfc2374_unit_directory_data),
1630	.key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1631	.data   = rfc2374_unit_directory_data
1632};
1633
1634#if IS_ENABLED(CONFIG_IPV6)
1635static const u32 rfc3146_unit_directory_data[] = {
1636	0x00040000,	/* directory_length		*/
1637	0x1200005e,	/* unit_specifier_id: IANA	*/
1638	0x81000003,	/* textual descriptor offset	*/
1639	0x13000002,	/* unit_sw_version: RFC 3146	*/
1640	0x81000005,	/* textual descriptor offset	*/
1641	0x00030000,	/* descriptor_length		*/
1642	0x00000000,	/* text				*/
1643	0x00000000,	/* minimal ASCII, en		*/
1644	0x49414e41,	/* I A N A			*/
1645	0x00030000,	/* descriptor_length		*/
1646	0x00000000,	/* text				*/
1647	0x00000000,	/* minimal ASCII, en		*/
1648	0x49507636,	/* I P v 6			*/
1649};
1650
1651static struct fw_descriptor rfc3146_unit_directory = {
1652	.length = ARRAY_SIZE(rfc3146_unit_directory_data),
1653	.key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1654	.data   = rfc3146_unit_directory_data
1655};
1656#endif
1657
1658static int __init fwnet_init(void)
1659{
1660	int err;
1661
1662	err = fw_core_add_descriptor(&rfc2374_unit_directory);
1663	if (err)
1664		return err;
1665
1666#if IS_ENABLED(CONFIG_IPV6)
1667	err = fw_core_add_descriptor(&rfc3146_unit_directory);
1668	if (err)
1669		goto out;
1670#endif
1671
1672	fwnet_packet_task_cache = kmem_cache_create("packet_task",
1673			sizeof(struct fwnet_packet_task), 0, 0, NULL);
1674	if (!fwnet_packet_task_cache) {
1675		err = -ENOMEM;
1676		goto out2;
1677	}
1678
1679	err = driver_register(&fwnet_driver.driver);
1680	if (!err)
1681		return 0;
1682
1683	kmem_cache_destroy(fwnet_packet_task_cache);
1684out2:
1685#if IS_ENABLED(CONFIG_IPV6)
1686	fw_core_remove_descriptor(&rfc3146_unit_directory);
1687out:
1688#endif
1689	fw_core_remove_descriptor(&rfc2374_unit_directory);
1690
1691	return err;
1692}
1693module_init(fwnet_init);
1694
1695static void __exit fwnet_cleanup(void)
1696{
1697	driver_unregister(&fwnet_driver.driver);
1698	kmem_cache_destroy(fwnet_packet_task_cache);
1699#if IS_ENABLED(CONFIG_IPV6)
1700	fw_core_remove_descriptor(&rfc3146_unit_directory);
1701#endif
1702	fw_core_remove_descriptor(&rfc2374_unit_directory);
1703}
1704module_exit(fwnet_cleanup);
1705
1706MODULE_AUTHOR("Jay Fenlason <fenlason@redhat.com>");
1707MODULE_DESCRIPTION("IP over IEEE1394 as per RFC 2734/3146");
1708MODULE_LICENSE("GPL");
1709MODULE_DEVICE_TABLE(ieee1394, fwnet_id_table);