linux/drivers/firewire/net.c
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   1/*
   2 * IPv4 over IEEE 1394, per RFC 2734
   3 * IPv6 over IEEE 1394, per RFC 3146
   4 *
   5 * Copyright (C) 2009 Jay Fenlason <fenlason@redhat.com>
   6 *
   7 * based on eth1394 by Ben Collins et al
   8 */
   9
  10#include <linux/bug.h>
  11#include <linux/compiler.h>
  12#include <linux/delay.h>
  13#include <linux/device.h>
  14#include <linux/ethtool.h>
  15#include <linux/firewire.h>
  16#include <linux/firewire-constants.h>
  17#include <linux/highmem.h>
  18#include <linux/in.h>
  19#include <linux/ip.h>
  20#include <linux/jiffies.h>
  21#include <linux/mod_devicetable.h>
  22#include <linux/module.h>
  23#include <linux/moduleparam.h>
  24#include <linux/mutex.h>
  25#include <linux/netdevice.h>
  26#include <linux/skbuff.h>
  27#include <linux/slab.h>
  28#include <linux/spinlock.h>
  29
  30#include <asm/unaligned.h>
  31#include <net/arp.h>
  32#include <net/firewire.h>
  33
  34/* rx limits */
  35#define FWNET_MAX_FRAGMENTS             30 /* arbitrary, > TX queue depth */
  36#define FWNET_ISO_PAGE_COUNT            (PAGE_SIZE < 16*1024 ? 4 : 2)
  37
  38/* tx limits */
  39#define FWNET_MAX_QUEUED_DATAGRAMS      20 /* < 64 = number of tlabels */
  40#define FWNET_MIN_QUEUED_DATAGRAMS      10 /* should keep AT DMA busy enough */
  41#define FWNET_TX_QUEUE_LEN              FWNET_MAX_QUEUED_DATAGRAMS /* ? */
  42
  43#define IEEE1394_BROADCAST_CHANNEL      31
  44#define IEEE1394_ALL_NODES              (0xffc0 | 0x003f)
  45#define IEEE1394_MAX_PAYLOAD_S100       512
  46#define FWNET_NO_FIFO_ADDR              (~0ULL)
  47
  48#define IANA_SPECIFIER_ID               0x00005eU
  49#define RFC2734_SW_VERSION              0x000001U
  50#define RFC3146_SW_VERSION              0x000002U
  51
  52#define IEEE1394_GASP_HDR_SIZE  8
  53
  54#define RFC2374_UNFRAG_HDR_SIZE 4
  55#define RFC2374_FRAG_HDR_SIZE   8
  56#define RFC2374_FRAG_OVERHEAD   4
  57
  58#define RFC2374_HDR_UNFRAG      0       /* unfragmented         */
  59#define RFC2374_HDR_FIRSTFRAG   1       /* first fragment       */
  60#define RFC2374_HDR_LASTFRAG    2       /* last fragment        */
  61#define RFC2374_HDR_INTFRAG     3       /* interior fragment    */
  62
  63static bool fwnet_hwaddr_is_multicast(u8 *ha)
  64{
  65        return !!(*ha & 1);
  66}
  67
  68/* IPv4 and IPv6 encapsulation header */
  69struct rfc2734_header {
  70        u32 w0;
  71        u32 w1;
  72};
  73
  74#define fwnet_get_hdr_lf(h)             (((h)->w0 & 0xc0000000) >> 30)
  75#define fwnet_get_hdr_ether_type(h)     (((h)->w0 & 0x0000ffff))
  76#define fwnet_get_hdr_dg_size(h)        ((((h)->w0 & 0x0fff0000) >> 16) + 1)
  77#define fwnet_get_hdr_fg_off(h)         (((h)->w0 & 0x00000fff))
  78#define fwnet_get_hdr_dgl(h)            (((h)->w1 & 0xffff0000) >> 16)
  79
  80#define fwnet_set_hdr_lf(lf)            ((lf) << 30)
  81#define fwnet_set_hdr_ether_type(et)    (et)
  82#define fwnet_set_hdr_dg_size(dgs)      (((dgs) - 1) << 16)
  83#define fwnet_set_hdr_fg_off(fgo)       (fgo)
  84
  85#define fwnet_set_hdr_dgl(dgl)          ((dgl) << 16)
  86
  87static inline void fwnet_make_uf_hdr(struct rfc2734_header *hdr,
  88                unsigned ether_type)
  89{
  90        hdr->w0 = fwnet_set_hdr_lf(RFC2374_HDR_UNFRAG)
  91                  | fwnet_set_hdr_ether_type(ether_type);
  92}
  93
  94static inline void fwnet_make_ff_hdr(struct rfc2734_header *hdr,
  95                unsigned ether_type, unsigned dg_size, unsigned dgl)
  96{
  97        hdr->w0 = fwnet_set_hdr_lf(RFC2374_HDR_FIRSTFRAG)
  98                  | fwnet_set_hdr_dg_size(dg_size)
  99                  | fwnet_set_hdr_ether_type(ether_type);
 100        hdr->w1 = fwnet_set_hdr_dgl(dgl);
 101}
 102
 103static inline void fwnet_make_sf_hdr(struct rfc2734_header *hdr,
 104                unsigned lf, unsigned dg_size, unsigned fg_off, unsigned dgl)
 105{
 106        hdr->w0 = fwnet_set_hdr_lf(lf)
 107                  | fwnet_set_hdr_dg_size(dg_size)
 108                  | fwnet_set_hdr_fg_off(fg_off);
 109        hdr->w1 = fwnet_set_hdr_dgl(dgl);
 110}
 111
 112/* This list keeps track of what parts of the datagram have been filled in */
 113struct fwnet_fragment_info {
 114        struct list_head fi_link;
 115        u16 offset;
 116        u16 len;
 117};
 118
 119struct fwnet_partial_datagram {
 120        struct list_head pd_link;
 121        struct list_head fi_list;
 122        struct sk_buff *skb;
 123        /* FIXME Why not use skb->data? */
 124        char *pbuf;
 125        u16 datagram_label;
 126        u16 ether_type;
 127        u16 datagram_size;
 128};
 129
 130static DEFINE_MUTEX(fwnet_device_mutex);
 131static LIST_HEAD(fwnet_device_list);
 132
 133struct fwnet_device {
 134        struct list_head dev_link;
 135        spinlock_t lock;
 136        enum {
 137                FWNET_BROADCAST_ERROR,
 138                FWNET_BROADCAST_RUNNING,
 139                FWNET_BROADCAST_STOPPED,
 140        } broadcast_state;
 141        struct fw_iso_context *broadcast_rcv_context;
 142        struct fw_iso_buffer broadcast_rcv_buffer;
 143        void **broadcast_rcv_buffer_ptrs;
 144        unsigned broadcast_rcv_next_ptr;
 145        unsigned num_broadcast_rcv_ptrs;
 146        unsigned rcv_buffer_size;
 147        /*
 148         * This value is the maximum unfragmented datagram size that can be
 149         * sent by the hardware.  It already has the GASP overhead and the
 150         * unfragmented datagram header overhead calculated into it.
 151         */
 152        unsigned broadcast_xmt_max_payload;
 153        u16 broadcast_xmt_datagramlabel;
 154
 155        /*
 156         * The CSR address that remote nodes must send datagrams to for us to
 157         * receive them.
 158         */
 159        struct fw_address_handler handler;
 160        u64 local_fifo;
 161
 162        /* Number of tx datagrams that have been queued but not yet acked */
 163        int queued_datagrams;
 164
 165        int peer_count;
 166        struct list_head peer_list;
 167        struct fw_card *card;
 168        struct net_device *netdev;
 169};
 170
 171struct fwnet_peer {
 172        struct list_head peer_link;
 173        struct fwnet_device *dev;
 174        u64 guid;
 175
 176        /* guarded by dev->lock */
 177        struct list_head pd_list; /* received partial datagrams */
 178        unsigned pdg_size;        /* pd_list size */
 179
 180        u16 datagram_label;       /* outgoing datagram label */
 181        u16 max_payload;          /* includes RFC2374_FRAG_HDR_SIZE overhead */
 182        int node_id;
 183        int generation;
 184        unsigned speed;
 185};
 186
 187/* This is our task struct. It's used for the packet complete callback.  */
 188struct fwnet_packet_task {
 189        struct fw_transaction transaction;
 190        struct rfc2734_header hdr;
 191        struct sk_buff *skb;
 192        struct fwnet_device *dev;
 193
 194        int outstanding_pkts;
 195        u64 fifo_addr;
 196        u16 dest_node;
 197        u16 max_payload;
 198        u8 generation;
 199        u8 speed;
 200        u8 enqueued;
 201};
 202
 203/*
 204 * Get fifo address embedded in hwaddr
 205 */
 206static __u64 fwnet_hwaddr_fifo(union fwnet_hwaddr *ha)
 207{
 208        return (u64)get_unaligned_be16(&ha->uc.fifo_hi) << 32
 209               | get_unaligned_be32(&ha->uc.fifo_lo);
 210}
 211
 212/*
 213 * saddr == NULL means use device source address.
 214 * daddr == NULL means leave destination address (eg unresolved arp).
 215 */
 216static int fwnet_header_create(struct sk_buff *skb, struct net_device *net,
 217                        unsigned short type, const void *daddr,
 218                        const void *saddr, unsigned len)
 219{
 220        struct fwnet_header *h;
 221
 222        h = skb_push(skb, sizeof(*h));
 223        put_unaligned_be16(type, &h->h_proto);
 224
 225        if (net->flags & (IFF_LOOPBACK | IFF_NOARP)) {
 226                memset(h->h_dest, 0, net->addr_len);
 227
 228                return net->hard_header_len;
 229        }
 230
 231        if (daddr) {
 232                memcpy(h->h_dest, daddr, net->addr_len);
 233
 234                return net->hard_header_len;
 235        }
 236
 237        return -net->hard_header_len;
 238}
 239
 240static int fwnet_header_cache(const struct neighbour *neigh,
 241                              struct hh_cache *hh, __be16 type)
 242{
 243        struct net_device *net;
 244        struct fwnet_header *h;
 245
 246        if (type == cpu_to_be16(ETH_P_802_3))
 247                return -1;
 248        net = neigh->dev;
 249        h = (struct fwnet_header *)((u8 *)hh->hh_data + HH_DATA_OFF(sizeof(*h)));
 250        h->h_proto = type;
 251        memcpy(h->h_dest, neigh->ha, net->addr_len);
 252        hh->hh_len = FWNET_HLEN;
 253
 254        return 0;
 255}
 256
 257/* Called by Address Resolution module to notify changes in address. */
 258static void fwnet_header_cache_update(struct hh_cache *hh,
 259                const struct net_device *net, const unsigned char *haddr)
 260{
 261        memcpy((u8 *)hh->hh_data + HH_DATA_OFF(FWNET_HLEN), haddr, net->addr_len);
 262}
 263
 264static int fwnet_header_parse(const struct sk_buff *skb, unsigned char *haddr)
 265{
 266        memcpy(haddr, skb->dev->dev_addr, FWNET_ALEN);
 267
 268        return FWNET_ALEN;
 269}
 270
 271static const struct header_ops fwnet_header_ops = {
 272        .create         = fwnet_header_create,
 273        .cache          = fwnet_header_cache,
 274        .cache_update   = fwnet_header_cache_update,
 275        .parse          = fwnet_header_parse,
 276};
 277
 278/* FIXME: is this correct for all cases? */
 279static bool fwnet_frag_overlap(struct fwnet_partial_datagram *pd,
 280                               unsigned offset, unsigned len)
 281{
 282        struct fwnet_fragment_info *fi;
 283        unsigned end = offset + len;
 284
 285        list_for_each_entry(fi, &pd->fi_list, fi_link)
 286                if (offset < fi->offset + fi->len && end > fi->offset)
 287                        return true;
 288
 289        return false;
 290}
 291
 292/* Assumes that new fragment does not overlap any existing fragments */
 293static struct fwnet_fragment_info *fwnet_frag_new(
 294        struct fwnet_partial_datagram *pd, unsigned offset, unsigned len)
 295{
 296        struct fwnet_fragment_info *fi, *fi2, *new;
 297        struct list_head *list;
 298
 299        list = &pd->fi_list;
 300        list_for_each_entry(fi, &pd->fi_list, fi_link) {
 301                if (fi->offset + fi->len == offset) {
 302                        /* The new fragment can be tacked on to the end */
 303                        /* Did the new fragment plug a hole? */
 304                        fi2 = list_entry(fi->fi_link.next,
 305                                         struct fwnet_fragment_info, fi_link);
 306                        if (fi->offset + fi->len == fi2->offset) {
 307                                /* glue fragments together */
 308                                fi->len += len + fi2->len;
 309                                list_del(&fi2->fi_link);
 310                                kfree(fi2);
 311                        } else {
 312                                fi->len += len;
 313                        }
 314
 315                        return fi;
 316                }
 317                if (offset + len == fi->offset) {
 318                        /* The new fragment can be tacked on to the beginning */
 319                        /* Did the new fragment plug a hole? */
 320                        fi2 = list_entry(fi->fi_link.prev,
 321                                         struct fwnet_fragment_info, fi_link);
 322                        if (fi2->offset + fi2->len == fi->offset) {
 323                                /* glue fragments together */
 324                                fi2->len += fi->len + len;
 325                                list_del(&fi->fi_link);
 326                                kfree(fi);
 327
 328                                return fi2;
 329                        }
 330                        fi->offset = offset;
 331                        fi->len += len;
 332
 333                        return fi;
 334                }
 335                if (offset > fi->offset + fi->len) {
 336                        list = &fi->fi_link;
 337                        break;
 338                }
 339                if (offset + len < fi->offset) {
 340                        list = fi->fi_link.prev;
 341                        break;
 342                }
 343        }
 344
 345        new = kmalloc(sizeof(*new), GFP_ATOMIC);
 346        if (!new)
 347                return NULL;
 348
 349        new->offset = offset;
 350        new->len = len;
 351        list_add(&new->fi_link, list);
 352
 353        return new;
 354}
 355
 356static struct fwnet_partial_datagram *fwnet_pd_new(struct net_device *net,
 357                struct fwnet_peer *peer, u16 datagram_label, unsigned dg_size,
 358                void *frag_buf, unsigned frag_off, unsigned frag_len)
 359{
 360        struct fwnet_partial_datagram *new;
 361        struct fwnet_fragment_info *fi;
 362
 363        new = kmalloc(sizeof(*new), GFP_ATOMIC);
 364        if (!new)
 365                goto fail;
 366
 367        INIT_LIST_HEAD(&new->fi_list);
 368        fi = fwnet_frag_new(new, frag_off, frag_len);
 369        if (fi == NULL)
 370                goto fail_w_new;
 371
 372        new->datagram_label = datagram_label;
 373        new->datagram_size = dg_size;
 374        new->skb = dev_alloc_skb(dg_size + LL_RESERVED_SPACE(net));
 375        if (new->skb == NULL)
 376                goto fail_w_fi;
 377
 378        skb_reserve(new->skb, LL_RESERVED_SPACE(net));
 379        new->pbuf = skb_put(new->skb, dg_size);
 380        memcpy(new->pbuf + frag_off, frag_buf, frag_len);
 381        list_add_tail(&new->pd_link, &peer->pd_list);
 382
 383        return new;
 384
 385fail_w_fi:
 386        kfree(fi);
 387fail_w_new:
 388        kfree(new);
 389fail:
 390        return NULL;
 391}
 392
 393static struct fwnet_partial_datagram *fwnet_pd_find(struct fwnet_peer *peer,
 394                                                    u16 datagram_label)
 395{
 396        struct fwnet_partial_datagram *pd;
 397
 398        list_for_each_entry(pd, &peer->pd_list, pd_link)
 399                if (pd->datagram_label == datagram_label)
 400                        return pd;
 401
 402        return NULL;
 403}
 404
 405
 406static void fwnet_pd_delete(struct fwnet_partial_datagram *old)
 407{
 408        struct fwnet_fragment_info *fi, *n;
 409
 410        list_for_each_entry_safe(fi, n, &old->fi_list, fi_link)
 411                kfree(fi);
 412
 413        list_del(&old->pd_link);
 414        dev_kfree_skb_any(old->skb);
 415        kfree(old);
 416}
 417
 418static bool fwnet_pd_update(struct fwnet_peer *peer,
 419                struct fwnet_partial_datagram *pd, void *frag_buf,
 420                unsigned frag_off, unsigned frag_len)
 421{
 422        if (fwnet_frag_new(pd, frag_off, frag_len) == NULL)
 423                return false;
 424
 425        memcpy(pd->pbuf + frag_off, frag_buf, frag_len);
 426
 427        /*
 428         * Move list entry to beginning of list so that oldest partial
 429         * datagrams percolate to the end of the list
 430         */
 431        list_move_tail(&pd->pd_link, &peer->pd_list);
 432
 433        return true;
 434}
 435
 436static bool fwnet_pd_is_complete(struct fwnet_partial_datagram *pd)
 437{
 438        struct fwnet_fragment_info *fi;
 439
 440        fi = list_entry(pd->fi_list.next, struct fwnet_fragment_info, fi_link);
 441
 442        return fi->len == pd->datagram_size;
 443}
 444
 445/* caller must hold dev->lock */
 446static struct fwnet_peer *fwnet_peer_find_by_guid(struct fwnet_device *dev,
 447                                                  u64 guid)
 448{
 449        struct fwnet_peer *peer;
 450
 451        list_for_each_entry(peer, &dev->peer_list, peer_link)
 452                if (peer->guid == guid)
 453                        return peer;
 454
 455        return NULL;
 456}
 457
 458/* caller must hold dev->lock */
 459static struct fwnet_peer *fwnet_peer_find_by_node_id(struct fwnet_device *dev,
 460                                                int node_id, int generation)
 461{
 462        struct fwnet_peer *peer;
 463
 464        list_for_each_entry(peer, &dev->peer_list, peer_link)
 465                if (peer->node_id    == node_id &&
 466                    peer->generation == generation)
 467                        return peer;
 468
 469        return NULL;
 470}
 471
 472/* See IEEE 1394-2008 table 6-4, table 8-8, table 16-18. */
 473static unsigned fwnet_max_payload(unsigned max_rec, unsigned speed)
 474{
 475        max_rec = min(max_rec, speed + 8);
 476        max_rec = clamp(max_rec, 8U, 11U); /* 512...4096 */
 477
 478        return (1 << (max_rec + 1)) - RFC2374_FRAG_HDR_SIZE;
 479}
 480
 481
 482static int fwnet_finish_incoming_packet(struct net_device *net,
 483                                        struct sk_buff *skb, u16 source_node_id,
 484                                        bool is_broadcast, u16 ether_type)
 485{
 486        struct fwnet_device *dev;
 487        int status;
 488        __be64 guid;
 489
 490        switch (ether_type) {
 491        case ETH_P_ARP:
 492        case ETH_P_IP:
 493#if IS_ENABLED(CONFIG_IPV6)
 494        case ETH_P_IPV6:
 495#endif
 496                break;
 497        default:
 498                goto err;
 499        }
 500
 501        dev = netdev_priv(net);
 502        /* Write metadata, and then pass to the receive level */
 503        skb->dev = net;
 504        skb->ip_summed = CHECKSUM_NONE;
 505
 506        /*
 507         * Parse the encapsulation header. This actually does the job of
 508         * converting to an ethernet-like pseudo frame header.
 509         */
 510        guid = cpu_to_be64(dev->card->guid);
 511        if (dev_hard_header(skb, net, ether_type,
 512                           is_broadcast ? net->broadcast : net->dev_addr,
 513                           NULL, skb->len) >= 0) {
 514                struct fwnet_header *eth;
 515                u16 *rawp;
 516                __be16 protocol;
 517
 518                skb_reset_mac_header(skb);
 519                skb_pull(skb, sizeof(*eth));
 520                eth = (struct fwnet_header *)skb_mac_header(skb);
 521                if (fwnet_hwaddr_is_multicast(eth->h_dest)) {
 522                        if (memcmp(eth->h_dest, net->broadcast,
 523                                   net->addr_len) == 0)
 524                                skb->pkt_type = PACKET_BROADCAST;
 525#if 0
 526                        else
 527                                skb->pkt_type = PACKET_MULTICAST;
 528#endif
 529                } else {
 530                        if (memcmp(eth->h_dest, net->dev_addr, net->addr_len))
 531                                skb->pkt_type = PACKET_OTHERHOST;
 532                }
 533                if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN) {
 534                        protocol = eth->h_proto;
 535                } else {
 536                        rawp = (u16 *)skb->data;
 537                        if (*rawp == 0xffff)
 538                                protocol = htons(ETH_P_802_3);
 539                        else
 540                                protocol = htons(ETH_P_802_2);
 541                }
 542                skb->protocol = protocol;
 543        }
 544        status = netif_rx(skb);
 545        if (status == NET_RX_DROP) {
 546                net->stats.rx_errors++;
 547                net->stats.rx_dropped++;
 548        } else {
 549                net->stats.rx_packets++;
 550                net->stats.rx_bytes += skb->len;
 551        }
 552
 553        return 0;
 554
 555 err:
 556        net->stats.rx_errors++;
 557        net->stats.rx_dropped++;
 558
 559        dev_kfree_skb_any(skb);
 560
 561        return -ENOENT;
 562}
 563
 564static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
 565                                 int source_node_id, int generation,
 566                                 bool is_broadcast)
 567{
 568        struct sk_buff *skb;
 569        struct net_device *net = dev->netdev;
 570        struct rfc2734_header hdr;
 571        unsigned lf;
 572        unsigned long flags;
 573        struct fwnet_peer *peer;
 574        struct fwnet_partial_datagram *pd;
 575        int fg_off;
 576        int dg_size;
 577        u16 datagram_label;
 578        int retval;
 579        u16 ether_type;
 580
 581        if (len <= RFC2374_UNFRAG_HDR_SIZE)
 582                return 0;
 583
 584        hdr.w0 = be32_to_cpu(buf[0]);
 585        lf = fwnet_get_hdr_lf(&hdr);
 586        if (lf == RFC2374_HDR_UNFRAG) {
 587                /*
 588                 * An unfragmented datagram has been received by the ieee1394
 589                 * bus. Build an skbuff around it so we can pass it to the
 590                 * high level network layer.
 591                 */
 592                ether_type = fwnet_get_hdr_ether_type(&hdr);
 593                buf++;
 594                len -= RFC2374_UNFRAG_HDR_SIZE;
 595
 596                skb = dev_alloc_skb(len + LL_RESERVED_SPACE(net));
 597                if (unlikely(!skb)) {
 598                        net->stats.rx_dropped++;
 599
 600                        return -ENOMEM;
 601                }
 602                skb_reserve(skb, LL_RESERVED_SPACE(net));
 603                skb_put_data(skb, buf, len);
 604
 605                return fwnet_finish_incoming_packet(net, skb, source_node_id,
 606                                                    is_broadcast, ether_type);
 607        }
 608
 609        /* A datagram fragment has been received, now the fun begins. */
 610
 611        if (len <= RFC2374_FRAG_HDR_SIZE)
 612                return 0;
 613
 614        hdr.w1 = ntohl(buf[1]);
 615        buf += 2;
 616        len -= RFC2374_FRAG_HDR_SIZE;
 617        if (lf == RFC2374_HDR_FIRSTFRAG) {
 618                ether_type = fwnet_get_hdr_ether_type(&hdr);
 619                fg_off = 0;
 620        } else {
 621                ether_type = 0;
 622                fg_off = fwnet_get_hdr_fg_off(&hdr);
 623        }
 624        datagram_label = fwnet_get_hdr_dgl(&hdr);
 625        dg_size = fwnet_get_hdr_dg_size(&hdr);
 626
 627        if (fg_off + len > dg_size)
 628                return 0;
 629
 630        spin_lock_irqsave(&dev->lock, flags);
 631
 632        peer = fwnet_peer_find_by_node_id(dev, source_node_id, generation);
 633        if (!peer) {
 634                retval = -ENOENT;
 635                goto fail;
 636        }
 637
 638        pd = fwnet_pd_find(peer, datagram_label);
 639        if (pd == NULL) {
 640                while (peer->pdg_size >= FWNET_MAX_FRAGMENTS) {
 641                        /* remove the oldest */
 642                        fwnet_pd_delete(list_first_entry(&peer->pd_list,
 643                                struct fwnet_partial_datagram, pd_link));
 644                        peer->pdg_size--;
 645                }
 646                pd = fwnet_pd_new(net, peer, datagram_label,
 647                                  dg_size, buf, fg_off, len);
 648                if (pd == NULL) {
 649                        retval = -ENOMEM;
 650                        goto fail;
 651                }
 652                peer->pdg_size++;
 653        } else {
 654                if (fwnet_frag_overlap(pd, fg_off, len) ||
 655                    pd->datagram_size != dg_size) {
 656                        /*
 657                         * Differing datagram sizes or overlapping fragments,
 658                         * discard old datagram and start a new one.
 659                         */
 660                        fwnet_pd_delete(pd);
 661                        pd = fwnet_pd_new(net, peer, datagram_label,
 662                                          dg_size, buf, fg_off, len);
 663                        if (pd == NULL) {
 664                                peer->pdg_size--;
 665                                retval = -ENOMEM;
 666                                goto fail;
 667                        }
 668                } else {
 669                        if (!fwnet_pd_update(peer, pd, buf, fg_off, len)) {
 670                                /*
 671                                 * Couldn't save off fragment anyway
 672                                 * so might as well obliterate the
 673                                 * datagram now.
 674                                 */
 675                                fwnet_pd_delete(pd);
 676                                peer->pdg_size--;
 677                                retval = -ENOMEM;
 678                                goto fail;
 679                        }
 680                }
 681        } /* new datagram or add to existing one */
 682
 683        if (lf == RFC2374_HDR_FIRSTFRAG)
 684                pd->ether_type = ether_type;
 685
 686        if (fwnet_pd_is_complete(pd)) {
 687                ether_type = pd->ether_type;
 688                peer->pdg_size--;
 689                skb = skb_get(pd->skb);
 690                fwnet_pd_delete(pd);
 691
 692                spin_unlock_irqrestore(&dev->lock, flags);
 693
 694                return fwnet_finish_incoming_packet(net, skb, source_node_id,
 695                                                    false, ether_type);
 696        }
 697        /*
 698         * Datagram is not complete, we're done for the
 699         * moment.
 700         */
 701        retval = 0;
 702 fail:
 703        spin_unlock_irqrestore(&dev->lock, flags);
 704
 705        return retval;
 706}
 707
 708static void fwnet_receive_packet(struct fw_card *card, struct fw_request *r,
 709                int tcode, int destination, int source, int generation,
 710                unsigned long long offset, void *payload, size_t length,
 711                void *callback_data)
 712{
 713        struct fwnet_device *dev = callback_data;
 714        int rcode;
 715
 716        if (destination == IEEE1394_ALL_NODES) {
 717                kfree(r);
 718
 719                return;
 720        }
 721
 722        if (offset != dev->handler.offset)
 723                rcode = RCODE_ADDRESS_ERROR;
 724        else if (tcode != TCODE_WRITE_BLOCK_REQUEST)
 725                rcode = RCODE_TYPE_ERROR;
 726        else if (fwnet_incoming_packet(dev, payload, length,
 727                                       source, generation, false) != 0) {
 728                dev_err(&dev->netdev->dev, "incoming packet failure\n");
 729                rcode = RCODE_CONFLICT_ERROR;
 730        } else
 731                rcode = RCODE_COMPLETE;
 732
 733        fw_send_response(card, r, rcode);
 734}
 735
 736static int gasp_source_id(__be32 *p)
 737{
 738        return be32_to_cpu(p[0]) >> 16;
 739}
 740
 741static u32 gasp_specifier_id(__be32 *p)
 742{
 743        return (be32_to_cpu(p[0]) & 0xffff) << 8 |
 744               (be32_to_cpu(p[1]) & 0xff000000) >> 24;
 745}
 746
 747static u32 gasp_version(__be32 *p)
 748{
 749        return be32_to_cpu(p[1]) & 0xffffff;
 750}
 751
 752static void fwnet_receive_broadcast(struct fw_iso_context *context,
 753                u32 cycle, size_t header_length, void *header, void *data)
 754{
 755        struct fwnet_device *dev;
 756        struct fw_iso_packet packet;
 757        __be16 *hdr_ptr;
 758        __be32 *buf_ptr;
 759        int retval;
 760        u32 length;
 761        unsigned long offset;
 762        unsigned long flags;
 763
 764        dev = data;
 765        hdr_ptr = header;
 766        length = be16_to_cpup(hdr_ptr);
 767
 768        spin_lock_irqsave(&dev->lock, flags);
 769
 770        offset = dev->rcv_buffer_size * dev->broadcast_rcv_next_ptr;
 771        buf_ptr = dev->broadcast_rcv_buffer_ptrs[dev->broadcast_rcv_next_ptr++];
 772        if (dev->broadcast_rcv_next_ptr == dev->num_broadcast_rcv_ptrs)
 773                dev->broadcast_rcv_next_ptr = 0;
 774
 775        spin_unlock_irqrestore(&dev->lock, flags);
 776
 777        if (length > IEEE1394_GASP_HDR_SIZE &&
 778            gasp_specifier_id(buf_ptr) == IANA_SPECIFIER_ID &&
 779            (gasp_version(buf_ptr) == RFC2734_SW_VERSION
 780#if IS_ENABLED(CONFIG_IPV6)
 781             || gasp_version(buf_ptr) == RFC3146_SW_VERSION
 782#endif
 783            ))
 784                fwnet_incoming_packet(dev, buf_ptr + 2,
 785                                      length - IEEE1394_GASP_HDR_SIZE,
 786                                      gasp_source_id(buf_ptr),
 787                                      context->card->generation, true);
 788
 789        packet.payload_length = dev->rcv_buffer_size;
 790        packet.interrupt = 1;
 791        packet.skip = 0;
 792        packet.tag = 3;
 793        packet.sy = 0;
 794        packet.header_length = IEEE1394_GASP_HDR_SIZE;
 795
 796        spin_lock_irqsave(&dev->lock, flags);
 797
 798        retval = fw_iso_context_queue(dev->broadcast_rcv_context, &packet,
 799                                      &dev->broadcast_rcv_buffer, offset);
 800
 801        spin_unlock_irqrestore(&dev->lock, flags);
 802
 803        if (retval >= 0)
 804                fw_iso_context_queue_flush(dev->broadcast_rcv_context);
 805        else
 806                dev_err(&dev->netdev->dev, "requeue failed\n");
 807}
 808
 809static struct kmem_cache *fwnet_packet_task_cache;
 810
 811static void fwnet_free_ptask(struct fwnet_packet_task *ptask)
 812{
 813        dev_kfree_skb_any(ptask->skb);
 814        kmem_cache_free(fwnet_packet_task_cache, ptask);
 815}
 816
 817/* Caller must hold dev->lock. */
 818static void dec_queued_datagrams(struct fwnet_device *dev)
 819{
 820        if (--dev->queued_datagrams == FWNET_MIN_QUEUED_DATAGRAMS)
 821                netif_wake_queue(dev->netdev);
 822}
 823
 824static int fwnet_send_packet(struct fwnet_packet_task *ptask);
 825
 826static void fwnet_transmit_packet_done(struct fwnet_packet_task *ptask)
 827{
 828        struct fwnet_device *dev = ptask->dev;
 829        struct sk_buff *skb = ptask->skb;
 830        unsigned long flags;
 831        bool free;
 832
 833        spin_lock_irqsave(&dev->lock, flags);
 834
 835        ptask->outstanding_pkts--;
 836
 837        /* Check whether we or the networking TX soft-IRQ is last user. */
 838        free = (ptask->outstanding_pkts == 0 && ptask->enqueued);
 839        if (free)
 840                dec_queued_datagrams(dev);
 841
 842        if (ptask->outstanding_pkts == 0) {
 843                dev->netdev->stats.tx_packets++;
 844                dev->netdev->stats.tx_bytes += skb->len;
 845        }
 846
 847        spin_unlock_irqrestore(&dev->lock, flags);
 848
 849        if (ptask->outstanding_pkts > 0) {
 850                u16 dg_size;
 851                u16 fg_off;
 852                u16 datagram_label;
 853                u16 lf;
 854
 855                /* Update the ptask to point to the next fragment and send it */
 856                lf = fwnet_get_hdr_lf(&ptask->hdr);
 857                switch (lf) {
 858                case RFC2374_HDR_LASTFRAG:
 859                case RFC2374_HDR_UNFRAG:
 860                default:
 861                        dev_err(&dev->netdev->dev,
 862                                "outstanding packet %x lf %x, header %x,%x\n",
 863                                ptask->outstanding_pkts, lf, ptask->hdr.w0,
 864                                ptask->hdr.w1);
 865                        BUG();
 866
 867                case RFC2374_HDR_FIRSTFRAG:
 868                        /* Set frag type here for future interior fragments */
 869                        dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
 870                        fg_off = ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
 871                        datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
 872                        break;
 873
 874                case RFC2374_HDR_INTFRAG:
 875                        dg_size = fwnet_get_hdr_dg_size(&ptask->hdr);
 876                        fg_off = fwnet_get_hdr_fg_off(&ptask->hdr)
 877                                  + ptask->max_payload - RFC2374_FRAG_HDR_SIZE;
 878                        datagram_label = fwnet_get_hdr_dgl(&ptask->hdr);
 879                        break;
 880                }
 881
 882                if (ptask->dest_node == IEEE1394_ALL_NODES) {
 883                        skb_pull(skb,
 884                                 ptask->max_payload + IEEE1394_GASP_HDR_SIZE);
 885                } else {
 886                        skb_pull(skb, ptask->max_payload);
 887                }
 888                if (ptask->outstanding_pkts > 1) {
 889                        fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_INTFRAG,
 890                                          dg_size, fg_off, datagram_label);
 891                } else {
 892                        fwnet_make_sf_hdr(&ptask->hdr, RFC2374_HDR_LASTFRAG,
 893                                          dg_size, fg_off, datagram_label);
 894                        ptask->max_payload = skb->len + RFC2374_FRAG_HDR_SIZE;
 895                }
 896                fwnet_send_packet(ptask);
 897        }
 898
 899        if (free)
 900                fwnet_free_ptask(ptask);
 901}
 902
 903static void fwnet_transmit_packet_failed(struct fwnet_packet_task *ptask)
 904{
 905        struct fwnet_device *dev = ptask->dev;
 906        unsigned long flags;
 907        bool free;
 908
 909        spin_lock_irqsave(&dev->lock, flags);
 910
 911        /* One fragment failed; don't try to send remaining fragments. */
 912        ptask->outstanding_pkts = 0;
 913
 914        /* Check whether we or the networking TX soft-IRQ is last user. */
 915        free = ptask->enqueued;
 916        if (free)
 917                dec_queued_datagrams(dev);
 918
 919        dev->netdev->stats.tx_dropped++;
 920        dev->netdev->stats.tx_errors++;
 921
 922        spin_unlock_irqrestore(&dev->lock, flags);
 923
 924        if (free)
 925                fwnet_free_ptask(ptask);
 926}
 927
 928static void fwnet_write_complete(struct fw_card *card, int rcode,
 929                                 void *payload, size_t length, void *data)
 930{
 931        struct fwnet_packet_task *ptask = data;
 932        static unsigned long j;
 933        static int last_rcode, errors_skipped;
 934
 935        if (rcode == RCODE_COMPLETE) {
 936                fwnet_transmit_packet_done(ptask);
 937        } else {
 938                if (printk_timed_ratelimit(&j,  1000) || rcode != last_rcode) {
 939                        dev_err(&ptask->dev->netdev->dev,
 940                                "fwnet_write_complete failed: %x (skipped %d)\n",
 941                                rcode, errors_skipped);
 942
 943                        errors_skipped = 0;
 944                        last_rcode = rcode;
 945                } else {
 946                        errors_skipped++;
 947                }
 948                fwnet_transmit_packet_failed(ptask);
 949        }
 950}
 951
 952static int fwnet_send_packet(struct fwnet_packet_task *ptask)
 953{
 954        struct fwnet_device *dev;
 955        unsigned tx_len;
 956        struct rfc2734_header *bufhdr;
 957        unsigned long flags;
 958        bool free;
 959
 960        dev = ptask->dev;
 961        tx_len = ptask->max_payload;
 962        switch (fwnet_get_hdr_lf(&ptask->hdr)) {
 963        case RFC2374_HDR_UNFRAG:
 964                bufhdr = skb_push(ptask->skb, RFC2374_UNFRAG_HDR_SIZE);
 965                put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
 966                break;
 967
 968        case RFC2374_HDR_FIRSTFRAG:
 969        case RFC2374_HDR_INTFRAG:
 970        case RFC2374_HDR_LASTFRAG:
 971                bufhdr = skb_push(ptask->skb, RFC2374_FRAG_HDR_SIZE);
 972                put_unaligned_be32(ptask->hdr.w0, &bufhdr->w0);
 973                put_unaligned_be32(ptask->hdr.w1, &bufhdr->w1);
 974                break;
 975
 976        default:
 977                BUG();
 978        }
 979        if (ptask->dest_node == IEEE1394_ALL_NODES) {
 980                u8 *p;
 981                int generation;
 982                int node_id;
 983                unsigned int sw_version;
 984
 985                /* ptask->generation may not have been set yet */
 986                generation = dev->card->generation;
 987                smp_rmb();
 988                node_id = dev->card->node_id;
 989
 990                switch (ptask->skb->protocol) {
 991                default:
 992                        sw_version = RFC2734_SW_VERSION;
 993                        break;
 994#if IS_ENABLED(CONFIG_IPV6)
 995                case htons(ETH_P_IPV6):
 996                        sw_version = RFC3146_SW_VERSION;
 997#endif
 998                }
 999
1000                p = skb_push(ptask->skb, IEEE1394_GASP_HDR_SIZE);
1001                put_unaligned_be32(node_id << 16 | IANA_SPECIFIER_ID >> 8, p);
1002                put_unaligned_be32((IANA_SPECIFIER_ID & 0xff) << 24
1003                                                | sw_version, &p[4]);
1004
1005                /* We should not transmit if broadcast_channel.valid == 0. */
1006                fw_send_request(dev->card, &ptask->transaction,
1007                                TCODE_STREAM_DATA,
1008                                fw_stream_packet_destination_id(3,
1009                                                IEEE1394_BROADCAST_CHANNEL, 0),
1010                                generation, SCODE_100, 0ULL, ptask->skb->data,
1011                                tx_len + 8, fwnet_write_complete, ptask);
1012
1013                spin_lock_irqsave(&dev->lock, flags);
1014
1015                /* If the AT tasklet already ran, we may be last user. */
1016                free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1017                if (!free)
1018                        ptask->enqueued = true;
1019                else
1020                        dec_queued_datagrams(dev);
1021
1022                spin_unlock_irqrestore(&dev->lock, flags);
1023
1024                goto out;
1025        }
1026
1027        fw_send_request(dev->card, &ptask->transaction,
1028                        TCODE_WRITE_BLOCK_REQUEST, ptask->dest_node,
1029                        ptask->generation, ptask->speed, ptask->fifo_addr,
1030                        ptask->skb->data, tx_len, fwnet_write_complete, ptask);
1031
1032        spin_lock_irqsave(&dev->lock, flags);
1033
1034        /* If the AT tasklet already ran, we may be last user. */
1035        free = (ptask->outstanding_pkts == 0 && !ptask->enqueued);
1036        if (!free)
1037                ptask->enqueued = true;
1038        else
1039                dec_queued_datagrams(dev);
1040
1041        spin_unlock_irqrestore(&dev->lock, flags);
1042
1043        netif_trans_update(dev->netdev);
1044 out:
1045        if (free)
1046                fwnet_free_ptask(ptask);
1047
1048        return 0;
1049}
1050
1051static void fwnet_fifo_stop(struct fwnet_device *dev)
1052{
1053        if (dev->local_fifo == FWNET_NO_FIFO_ADDR)
1054                return;
1055
1056        fw_core_remove_address_handler(&dev->handler);
1057        dev->local_fifo = FWNET_NO_FIFO_ADDR;
1058}
1059
1060static int fwnet_fifo_start(struct fwnet_device *dev)
1061{
1062        int retval;
1063
1064        if (dev->local_fifo != FWNET_NO_FIFO_ADDR)
1065                return 0;
1066
1067        dev->handler.length = 4096;
1068        dev->handler.address_callback = fwnet_receive_packet;
1069        dev->handler.callback_data = dev;
1070
1071        retval = fw_core_add_address_handler(&dev->handler,
1072                                             &fw_high_memory_region);
1073        if (retval < 0)
1074                return retval;
1075
1076        dev->local_fifo = dev->handler.offset;
1077
1078        return 0;
1079}
1080
1081static void __fwnet_broadcast_stop(struct fwnet_device *dev)
1082{
1083        unsigned u;
1084
1085        if (dev->broadcast_state != FWNET_BROADCAST_ERROR) {
1086                for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++)
1087                        kunmap(dev->broadcast_rcv_buffer.pages[u]);
1088                fw_iso_buffer_destroy(&dev->broadcast_rcv_buffer, dev->card);
1089        }
1090        if (dev->broadcast_rcv_context) {
1091                fw_iso_context_destroy(dev->broadcast_rcv_context);
1092                dev->broadcast_rcv_context = NULL;
1093        }
1094        kfree(dev->broadcast_rcv_buffer_ptrs);
1095        dev->broadcast_rcv_buffer_ptrs = NULL;
1096        dev->broadcast_state = FWNET_BROADCAST_ERROR;
1097}
1098
1099static void fwnet_broadcast_stop(struct fwnet_device *dev)
1100{
1101        if (dev->broadcast_state == FWNET_BROADCAST_ERROR)
1102                return;
1103        fw_iso_context_stop(dev->broadcast_rcv_context);
1104        __fwnet_broadcast_stop(dev);
1105}
1106
1107static int fwnet_broadcast_start(struct fwnet_device *dev)
1108{
1109        struct fw_iso_context *context;
1110        int retval;
1111        unsigned num_packets;
1112        unsigned max_receive;
1113        struct fw_iso_packet packet;
1114        unsigned long offset;
1115        void **ptrptr;
1116        unsigned u;
1117
1118        if (dev->broadcast_state != FWNET_BROADCAST_ERROR)
1119                return 0;
1120
1121        max_receive = 1U << (dev->card->max_receive + 1);
1122        num_packets = (FWNET_ISO_PAGE_COUNT * PAGE_SIZE) / max_receive;
1123
1124        ptrptr = kmalloc_array(num_packets, sizeof(void *), GFP_KERNEL);
1125        if (!ptrptr) {
1126                retval = -ENOMEM;
1127                goto failed;
1128        }
1129        dev->broadcast_rcv_buffer_ptrs = ptrptr;
1130
1131        context = fw_iso_context_create(dev->card, FW_ISO_CONTEXT_RECEIVE,
1132                                        IEEE1394_BROADCAST_CHANNEL,
1133                                        dev->card->link_speed, 8,
1134                                        fwnet_receive_broadcast, dev);
1135        if (IS_ERR(context)) {
1136                retval = PTR_ERR(context);
1137                goto failed;
1138        }
1139
1140        retval = fw_iso_buffer_init(&dev->broadcast_rcv_buffer, dev->card,
1141                                    FWNET_ISO_PAGE_COUNT, DMA_FROM_DEVICE);
1142        if (retval < 0)
1143                goto failed;
1144
1145        dev->broadcast_state = FWNET_BROADCAST_STOPPED;
1146
1147        for (u = 0; u < FWNET_ISO_PAGE_COUNT; u++) {
1148                void *ptr;
1149                unsigned v;
1150
1151                ptr = kmap(dev->broadcast_rcv_buffer.pages[u]);
1152                for (v = 0; v < num_packets / FWNET_ISO_PAGE_COUNT; v++)
1153                        *ptrptr++ = (void *) ((char *)ptr + v * max_receive);
1154        }
1155        dev->broadcast_rcv_context = context;
1156
1157        packet.payload_length = max_receive;
1158        packet.interrupt = 1;
1159        packet.skip = 0;
1160        packet.tag = 3;
1161        packet.sy = 0;
1162        packet.header_length = IEEE1394_GASP_HDR_SIZE;
1163        offset = 0;
1164
1165        for (u = 0; u < num_packets; u++) {
1166                retval = fw_iso_context_queue(context, &packet,
1167                                &dev->broadcast_rcv_buffer, offset);
1168                if (retval < 0)
1169                        goto failed;
1170
1171                offset += max_receive;
1172        }
1173        dev->num_broadcast_rcv_ptrs = num_packets;
1174        dev->rcv_buffer_size = max_receive;
1175        dev->broadcast_rcv_next_ptr = 0U;
1176        retval = fw_iso_context_start(context, -1, 0,
1177                        FW_ISO_CONTEXT_MATCH_ALL_TAGS); /* ??? sync */
1178        if (retval < 0)
1179                goto failed;
1180
1181        /* FIXME: adjust it according to the min. speed of all known peers? */
1182        dev->broadcast_xmt_max_payload = IEEE1394_MAX_PAYLOAD_S100
1183                        - IEEE1394_GASP_HDR_SIZE - RFC2374_UNFRAG_HDR_SIZE;
1184        dev->broadcast_state = FWNET_BROADCAST_RUNNING;
1185
1186        return 0;
1187
1188 failed:
1189        __fwnet_broadcast_stop(dev);
1190        return retval;
1191}
1192
1193static void set_carrier_state(struct fwnet_device *dev)
1194{
1195        if (dev->peer_count > 1)
1196                netif_carrier_on(dev->netdev);
1197        else
1198                netif_carrier_off(dev->netdev);
1199}
1200
1201/* ifup */
1202static int fwnet_open(struct net_device *net)
1203{
1204        struct fwnet_device *dev = netdev_priv(net);
1205        int ret;
1206
1207        ret = fwnet_broadcast_start(dev);
1208        if (ret)
1209                return ret;
1210
1211        netif_start_queue(net);
1212
1213        spin_lock_irq(&dev->lock);
1214        set_carrier_state(dev);
1215        spin_unlock_irq(&dev->lock);
1216
1217        return 0;
1218}
1219
1220/* ifdown */
1221static int fwnet_stop(struct net_device *net)
1222{
1223        struct fwnet_device *dev = netdev_priv(net);
1224
1225        netif_stop_queue(net);
1226        fwnet_broadcast_stop(dev);
1227
1228        return 0;
1229}
1230
1231static netdev_tx_t fwnet_tx(struct sk_buff *skb, struct net_device *net)
1232{
1233        struct fwnet_header hdr_buf;
1234        struct fwnet_device *dev = netdev_priv(net);
1235        __be16 proto;
1236        u16 dest_node;
1237        unsigned max_payload;
1238        u16 dg_size;
1239        u16 *datagram_label_ptr;
1240        struct fwnet_packet_task *ptask;
1241        struct fwnet_peer *peer;
1242        unsigned long flags;
1243
1244        spin_lock_irqsave(&dev->lock, flags);
1245
1246        /* Can this happen? */
1247        if (netif_queue_stopped(dev->netdev)) {
1248                spin_unlock_irqrestore(&dev->lock, flags);
1249
1250                return NETDEV_TX_BUSY;
1251        }
1252
1253        ptask = kmem_cache_alloc(fwnet_packet_task_cache, GFP_ATOMIC);
1254        if (ptask == NULL)
1255                goto fail;
1256
1257        skb = skb_share_check(skb, GFP_ATOMIC);
1258        if (!skb)
1259                goto fail;
1260
1261        /*
1262         * Make a copy of the driver-specific header.
1263         * We might need to rebuild the header on tx failure.
1264         */
1265        memcpy(&hdr_buf, skb->data, sizeof(hdr_buf));
1266        proto = hdr_buf.h_proto;
1267
1268        switch (proto) {
1269        case htons(ETH_P_ARP):
1270        case htons(ETH_P_IP):
1271#if IS_ENABLED(CONFIG_IPV6)
1272        case htons(ETH_P_IPV6):
1273#endif
1274                break;
1275        default:
1276                goto fail;
1277        }
1278
1279        skb_pull(skb, sizeof(hdr_buf));
1280        dg_size = skb->len;
1281
1282        /*
1283         * Set the transmission type for the packet.  ARP packets and IP
1284         * broadcast packets are sent via GASP.
1285         */
1286        if (fwnet_hwaddr_is_multicast(hdr_buf.h_dest)) {
1287                max_payload        = dev->broadcast_xmt_max_payload;
1288                datagram_label_ptr = &dev->broadcast_xmt_datagramlabel;
1289
1290                ptask->fifo_addr   = FWNET_NO_FIFO_ADDR;
1291                ptask->generation  = 0;
1292                ptask->dest_node   = IEEE1394_ALL_NODES;
1293                ptask->speed       = SCODE_100;
1294        } else {
1295                union fwnet_hwaddr *ha = (union fwnet_hwaddr *)hdr_buf.h_dest;
1296                __be64 guid = get_unaligned(&ha->uc.uniq_id);
1297                u8 generation;
1298
1299                peer = fwnet_peer_find_by_guid(dev, be64_to_cpu(guid));
1300                if (!peer)
1301                        goto fail;
1302
1303                generation         = peer->generation;
1304                dest_node          = peer->node_id;
1305                max_payload        = peer->max_payload;
1306                datagram_label_ptr = &peer->datagram_label;
1307
1308                ptask->fifo_addr   = fwnet_hwaddr_fifo(ha);
1309                ptask->generation  = generation;
1310                ptask->dest_node   = dest_node;
1311                ptask->speed       = peer->speed;
1312        }
1313
1314        ptask->hdr.w0 = 0;
1315        ptask->hdr.w1 = 0;
1316        ptask->skb = skb;
1317        ptask->dev = dev;
1318
1319        /* Does it all fit in one packet? */
1320        if (dg_size <= max_payload) {
1321                fwnet_make_uf_hdr(&ptask->hdr, ntohs(proto));
1322                ptask->outstanding_pkts = 1;
1323                max_payload = dg_size + RFC2374_UNFRAG_HDR_SIZE;
1324        } else {
1325                u16 datagram_label;
1326
1327                max_payload -= RFC2374_FRAG_OVERHEAD;
1328                datagram_label = (*datagram_label_ptr)++;
1329                fwnet_make_ff_hdr(&ptask->hdr, ntohs(proto), dg_size,
1330                                  datagram_label);
1331                ptask->outstanding_pkts = DIV_ROUND_UP(dg_size, max_payload);
1332                max_payload += RFC2374_FRAG_HDR_SIZE;
1333        }
1334
1335        if (++dev->queued_datagrams == FWNET_MAX_QUEUED_DATAGRAMS)
1336                netif_stop_queue(dev->netdev);
1337
1338        spin_unlock_irqrestore(&dev->lock, flags);
1339
1340        ptask->max_payload = max_payload;
1341        ptask->enqueued    = 0;
1342
1343        fwnet_send_packet(ptask);
1344
1345        return NETDEV_TX_OK;
1346
1347 fail:
1348        spin_unlock_irqrestore(&dev->lock, flags);
1349
1350        if (ptask)
1351                kmem_cache_free(fwnet_packet_task_cache, ptask);
1352
1353        if (skb != NULL)
1354                dev_kfree_skb(skb);
1355
1356        net->stats.tx_dropped++;
1357        net->stats.tx_errors++;
1358
1359        /*
1360         * FIXME: According to a patch from 2003-02-26, "returning non-zero
1361         * causes serious problems" here, allegedly.  Before that patch,
1362         * -ERRNO was returned which is not appropriate under Linux 2.6.
1363         * Perhaps more needs to be done?  Stop the queue in serious
1364         * conditions and restart it elsewhere?
1365         */
1366        return NETDEV_TX_OK;
1367}
1368
1369static const struct ethtool_ops fwnet_ethtool_ops = {
1370        .get_link       = ethtool_op_get_link,
1371};
1372
1373static const struct net_device_ops fwnet_netdev_ops = {
1374        .ndo_open       = fwnet_open,
1375        .ndo_stop       = fwnet_stop,
1376        .ndo_start_xmit = fwnet_tx,
1377};
1378
1379static void fwnet_init_dev(struct net_device *net)
1380{
1381        net->header_ops         = &fwnet_header_ops;
1382        net->netdev_ops         = &fwnet_netdev_ops;
1383        net->watchdog_timeo     = 2 * HZ;
1384        net->flags              = IFF_BROADCAST | IFF_MULTICAST;
1385        net->features           = NETIF_F_HIGHDMA;
1386        net->addr_len           = FWNET_ALEN;
1387        net->hard_header_len    = FWNET_HLEN;
1388        net->type               = ARPHRD_IEEE1394;
1389        net->tx_queue_len       = FWNET_TX_QUEUE_LEN;
1390        net->ethtool_ops        = &fwnet_ethtool_ops;
1391}
1392
1393/* caller must hold fwnet_device_mutex */
1394static struct fwnet_device *fwnet_dev_find(struct fw_card *card)
1395{
1396        struct fwnet_device *dev;
1397
1398        list_for_each_entry(dev, &fwnet_device_list, dev_link)
1399                if (dev->card == card)
1400                        return dev;
1401
1402        return NULL;
1403}
1404
1405static int fwnet_add_peer(struct fwnet_device *dev,
1406                          struct fw_unit *unit, struct fw_device *device)
1407{
1408        struct fwnet_peer *peer;
1409
1410        peer = kmalloc(sizeof(*peer), GFP_KERNEL);
1411        if (!peer)
1412                return -ENOMEM;
1413
1414        dev_set_drvdata(&unit->device, peer);
1415
1416        peer->dev = dev;
1417        peer->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1418        INIT_LIST_HEAD(&peer->pd_list);
1419        peer->pdg_size = 0;
1420        peer->datagram_label = 0;
1421        peer->speed = device->max_speed;
1422        peer->max_payload = fwnet_max_payload(device->max_rec, peer->speed);
1423
1424        peer->generation = device->generation;
1425        smp_rmb();
1426        peer->node_id = device->node_id;
1427
1428        spin_lock_irq(&dev->lock);
1429        list_add_tail(&peer->peer_link, &dev->peer_list);
1430        dev->peer_count++;
1431        set_carrier_state(dev);
1432        spin_unlock_irq(&dev->lock);
1433
1434        return 0;
1435}
1436
1437static int fwnet_probe(struct fw_unit *unit,
1438                       const struct ieee1394_device_id *id)
1439{
1440        struct fw_device *device = fw_parent_device(unit);
1441        struct fw_card *card = device->card;
1442        struct net_device *net;
1443        bool allocated_netdev = false;
1444        struct fwnet_device *dev;
1445        int ret;
1446        union fwnet_hwaddr *ha;
1447
1448        mutex_lock(&fwnet_device_mutex);
1449
1450        dev = fwnet_dev_find(card);
1451        if (dev) {
1452                net = dev->netdev;
1453                goto have_dev;
1454        }
1455
1456        net = alloc_netdev(sizeof(*dev), "firewire%d", NET_NAME_UNKNOWN,
1457                           fwnet_init_dev);
1458        if (net == NULL) {
1459                mutex_unlock(&fwnet_device_mutex);
1460                return -ENOMEM;
1461        }
1462
1463        allocated_netdev = true;
1464        SET_NETDEV_DEV(net, card->device);
1465        dev = netdev_priv(net);
1466
1467        spin_lock_init(&dev->lock);
1468        dev->broadcast_state = FWNET_BROADCAST_ERROR;
1469        dev->broadcast_rcv_context = NULL;
1470        dev->broadcast_xmt_max_payload = 0;
1471        dev->broadcast_xmt_datagramlabel = 0;
1472        dev->local_fifo = FWNET_NO_FIFO_ADDR;
1473        dev->queued_datagrams = 0;
1474        INIT_LIST_HEAD(&dev->peer_list);
1475        dev->card = card;
1476        dev->netdev = net;
1477
1478        ret = fwnet_fifo_start(dev);
1479        if (ret < 0)
1480                goto out;
1481        dev->local_fifo = dev->handler.offset;
1482
1483        /*
1484         * default MTU: RFC 2734 cl. 4, RFC 3146 cl. 4
1485         * maximum MTU: RFC 2734 cl. 4.2, fragment encapsulation header's
1486         *              maximum possible datagram_size + 1 = 0xfff + 1
1487         */
1488        net->mtu = 1500U;
1489        net->min_mtu = ETH_MIN_MTU;
1490        net->max_mtu = 4096U;
1491
1492        /* Set our hardware address while we're at it */
1493        ha = (union fwnet_hwaddr *)net->dev_addr;
1494        put_unaligned_be64(card->guid, &ha->uc.uniq_id);
1495        ha->uc.max_rec = dev->card->max_receive;
1496        ha->uc.sspd = dev->card->link_speed;
1497        put_unaligned_be16(dev->local_fifo >> 32, &ha->uc.fifo_hi);
1498        put_unaligned_be32(dev->local_fifo & 0xffffffff, &ha->uc.fifo_lo);
1499
1500        memset(net->broadcast, -1, net->addr_len);
1501
1502        ret = register_netdev(net);
1503        if (ret)
1504                goto out;
1505
1506        list_add_tail(&dev->dev_link, &fwnet_device_list);
1507        dev_notice(&net->dev, "IP over IEEE 1394 on card %s\n",
1508                   dev_name(card->device));
1509 have_dev:
1510        ret = fwnet_add_peer(dev, unit, device);
1511        if (ret && allocated_netdev) {
1512                unregister_netdev(net);
1513                list_del(&dev->dev_link);
1514 out:
1515                fwnet_fifo_stop(dev);
1516                free_netdev(net);
1517        }
1518
1519        mutex_unlock(&fwnet_device_mutex);
1520
1521        return ret;
1522}
1523
1524/*
1525 * FIXME abort partially sent fragmented datagrams,
1526 * discard partially received fragmented datagrams
1527 */
1528static void fwnet_update(struct fw_unit *unit)
1529{
1530        struct fw_device *device = fw_parent_device(unit);
1531        struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1532        int generation;
1533
1534        generation = device->generation;
1535
1536        spin_lock_irq(&peer->dev->lock);
1537        peer->node_id    = device->node_id;
1538        peer->generation = generation;
1539        spin_unlock_irq(&peer->dev->lock);
1540}
1541
1542static void fwnet_remove_peer(struct fwnet_peer *peer, struct fwnet_device *dev)
1543{
1544        struct fwnet_partial_datagram *pd, *pd_next;
1545
1546        spin_lock_irq(&dev->lock);
1547        list_del(&peer->peer_link);
1548        dev->peer_count--;
1549        set_carrier_state(dev);
1550        spin_unlock_irq(&dev->lock);
1551
1552        list_for_each_entry_safe(pd, pd_next, &peer->pd_list, pd_link)
1553                fwnet_pd_delete(pd);
1554
1555        kfree(peer);
1556}
1557
1558static void fwnet_remove(struct fw_unit *unit)
1559{
1560        struct fwnet_peer *peer = dev_get_drvdata(&unit->device);
1561        struct fwnet_device *dev = peer->dev;
1562        struct net_device *net;
1563        int i;
1564
1565        mutex_lock(&fwnet_device_mutex);
1566
1567        net = dev->netdev;
1568
1569        fwnet_remove_peer(peer, dev);
1570
1571        if (list_empty(&dev->peer_list)) {
1572                unregister_netdev(net);
1573
1574                fwnet_fifo_stop(dev);
1575
1576                for (i = 0; dev->queued_datagrams && i < 5; i++)
1577                        ssleep(1);
1578                WARN_ON(dev->queued_datagrams);
1579                list_del(&dev->dev_link);
1580
1581                free_netdev(net);
1582        }
1583
1584        mutex_unlock(&fwnet_device_mutex);
1585}
1586
1587static const struct ieee1394_device_id fwnet_id_table[] = {
1588        {
1589                .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1590                                IEEE1394_MATCH_VERSION,
1591                .specifier_id = IANA_SPECIFIER_ID,
1592                .version      = RFC2734_SW_VERSION,
1593        },
1594#if IS_ENABLED(CONFIG_IPV6)
1595        {
1596                .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1597                                IEEE1394_MATCH_VERSION,
1598                .specifier_id = IANA_SPECIFIER_ID,
1599                .version      = RFC3146_SW_VERSION,
1600        },
1601#endif
1602        { }
1603};
1604
1605static struct fw_driver fwnet_driver = {
1606        .driver = {
1607                .owner  = THIS_MODULE,
1608                .name   = KBUILD_MODNAME,
1609                .bus    = &fw_bus_type,
1610        },
1611        .probe    = fwnet_probe,
1612        .update   = fwnet_update,
1613        .remove   = fwnet_remove,
1614        .id_table = fwnet_id_table,
1615};
1616
1617static const u32 rfc2374_unit_directory_data[] = {
1618        0x00040000,     /* directory_length             */
1619        0x1200005e,     /* unit_specifier_id: IANA      */
1620        0x81000003,     /* textual descriptor offset    */
1621        0x13000001,     /* unit_sw_version: RFC 2734    */
1622        0x81000005,     /* textual descriptor offset    */
1623        0x00030000,     /* descriptor_length            */
1624        0x00000000,     /* text                         */
1625        0x00000000,     /* minimal ASCII, en            */
1626        0x49414e41,     /* I A N A                      */
1627        0x00030000,     /* descriptor_length            */
1628        0x00000000,     /* text                         */
1629        0x00000000,     /* minimal ASCII, en            */
1630        0x49507634,     /* I P v 4                      */
1631};
1632
1633static struct fw_descriptor rfc2374_unit_directory = {
1634        .length = ARRAY_SIZE(rfc2374_unit_directory_data),
1635        .key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1636        .data   = rfc2374_unit_directory_data
1637};
1638
1639#if IS_ENABLED(CONFIG_IPV6)
1640static const u32 rfc3146_unit_directory_data[] = {
1641        0x00040000,     /* directory_length             */
1642        0x1200005e,     /* unit_specifier_id: IANA      */
1643        0x81000003,     /* textual descriptor offset    */
1644        0x13000002,     /* unit_sw_version: RFC 3146    */
1645        0x81000005,     /* textual descriptor offset    */
1646        0x00030000,     /* descriptor_length            */
1647        0x00000000,     /* text                         */
1648        0x00000000,     /* minimal ASCII, en            */
1649        0x49414e41,     /* I A N A                      */
1650        0x00030000,     /* descriptor_length            */
1651        0x00000000,     /* text                         */
1652        0x00000000,     /* minimal ASCII, en            */
1653        0x49507636,     /* I P v 6                      */
1654};
1655
1656static struct fw_descriptor rfc3146_unit_directory = {
1657        .length = ARRAY_SIZE(rfc3146_unit_directory_data),
1658        .key    = (CSR_DIRECTORY | CSR_UNIT) << 24,
1659        .data   = rfc3146_unit_directory_data
1660};
1661#endif
1662
1663static int __init fwnet_init(void)
1664{
1665        int err;
1666
1667        err = fw_core_add_descriptor(&rfc2374_unit_directory);
1668        if (err)
1669                return err;
1670
1671#if IS_ENABLED(CONFIG_IPV6)
1672        err = fw_core_add_descriptor(&rfc3146_unit_directory);
1673        if (err)
1674                goto out;
1675#endif
1676
1677        fwnet_packet_task_cache = kmem_cache_create("packet_task",
1678                        sizeof(struct fwnet_packet_task), 0, 0, NULL);
1679        if (!fwnet_packet_task_cache) {
1680                err = -ENOMEM;
1681                goto out2;
1682        }
1683
1684        err = driver_register(&fwnet_driver.driver);
1685        if (!err)
1686                return 0;
1687
1688        kmem_cache_destroy(fwnet_packet_task_cache);
1689out2:
1690#if IS_ENABLED(CONFIG_IPV6)
1691        fw_core_remove_descriptor(&rfc3146_unit_directory);
1692out:
1693#endif
1694        fw_core_remove_descriptor(&rfc2374_unit_directory);
1695
1696        return err;
1697}
1698module_init(fwnet_init);
1699
1700static void __exit fwnet_cleanup(void)
1701{
1702        driver_unregister(&fwnet_driver.driver);
1703        kmem_cache_destroy(fwnet_packet_task_cache);
1704#if IS_ENABLED(CONFIG_IPV6)
1705        fw_core_remove_descriptor(&rfc3146_unit_directory);
1706#endif
1707        fw_core_remove_descriptor(&rfc2374_unit_directory);
1708}
1709module_exit(fwnet_cleanup);
1710
1711MODULE_AUTHOR("Jay Fenlason <fenlason@redhat.com>");
1712MODULE_DESCRIPTION("IP over IEEE1394 as per RFC 2734/3146");
1713MODULE_LICENSE("GPL");
1714MODULE_DEVICE_TABLE(ieee1394, fwnet_id_table);
1715