drivers/s390/net/ctcm_main.c

   1 /*
   2  * drivers/s390/net/ctcm_main.c
   3  *
   4  * Copyright IBM Corp. 2001, 2007
   5  * Author(s):
   6  *      Original CTC driver(s):
   7  *              Fritz Elfert (felfert@millenux.com)
   8  *              Dieter Wellerdiek (wel@de.ibm.com)
   9  *              Martin Schwidefsky (schwidefsky@de.ibm.com)
  10  *              Denis Joseph Barrow (barrow_dj@yahoo.com)
  11  *              Jochen Roehrig (roehrig@de.ibm.com)
  12  *              Cornelia Huck <cornelia.huck@de.ibm.com>
  13  *      MPC additions:
  14  *              Belinda Thompson (belindat@us.ibm.com)
  15  *              Andy Richter (richtera@us.ibm.com)
  16  *      Revived by:
  17  *              Peter Tiedemann (ptiedem@de.ibm.com)
  18  */
  19
  20 #undef DEBUG
  21 #undef DEBUGDATA
  22 #undef DEBUGCCW
  23
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/kernel.h>
  27 #include <linux/slab.h>
  28 #include <linux/errno.h>
  29 #include <linux/types.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/timer.h>
  32 #include <linux/bitops.h>
  33
  34 #include <linux/signal.h>
  35 #include <linux/string.h>
  36
  37 #include <linux/ip.h>
  38 #include <linux/if_arp.h>
  39 #include <linux/tcp.h>
  40 #include <linux/skbuff.h>
  41 #include <linux/ctype.h>
  42 #include <net/dst.h>
  43
  44 #include <linux/io.h>
  45 #include <asm/ccwdev.h>
  46 #include <asm/ccwgroup.h>
  47 #include <linux/uaccess.h>
  48
  49 #include <asm/idals.h>
  50
  51 #include "cu3088.h"
  52 #include "ctcm_fsms.h"
  53 #include "ctcm_main.h"
  54
  55 /* Some common global variables */
  56
  57 /*
  58  * Linked list of all detected channels.
  59  */
  60 struct channel *channels;
  61
  62 /**
  63  * Unpack a just received skb and hand it over to
  64  * upper layers.
  65  *
  66  *  ch          The channel where this skb has been received.
  67  *  pskb        The received skb.
  68  */
  69 void ctcm_unpack_skb(struct channel *ch, struct sk_buff *pskb)
  70 {
  71         struct net_device *dev = ch->netdev;
  72         struct ctcm_priv *priv = dev->priv;
  73         __u16 len = *((__u16 *) pskb->data);
  74
  75         skb_put(pskb, 2 + LL_HEADER_LENGTH);
  76         skb_pull(pskb, 2);
  77         pskb->dev = dev;
  78         pskb->ip_summed = CHECKSUM_UNNECESSARY;
  79         while (len > 0) {
  80                 struct sk_buff *skb;
  81                 int skblen;
  82                 struct ll_header *header = (struct ll_header *)pskb->data;
  83
  84                 skb_pull(pskb, LL_HEADER_LENGTH);
  85                 if ((ch->protocol == CTCM_PROTO_S390) &&
  86                     (header->type != ETH_P_IP)) {
  87                         if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
  88                                 ch->logflags |= LOG_FLAG_ILLEGALPKT;
  89                                 /*
  90                                  * Check packet type only if we stick strictly
  91                                  * to S/390's protocol of OS390. This only
  92                                  * supports IP. Otherwise allow any packet
  93                                  * type.
  94                                  */
  95                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
  96                                         "%s(%s): Illegal packet type 0x%04x"
  97                                         " - dropping",
  98                                         CTCM_FUNTAIL, dev->name, header->type);
  99                         }
 100                         priv->stats.rx_dropped++;
 101                         priv->stats.rx_frame_errors++;
 102                         return;
 103                 }
 104                 pskb->protocol = ntohs(header->type);
 105                 if (header->length <= LL_HEADER_LENGTH) {
 106                         if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
 107                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 108                                         "%s(%s): Illegal packet size %d(%d,%d)"
 109                                         "- dropping",
 110                                         CTCM_FUNTAIL, dev->name,
 111                                         header->length, dev->mtu, len);
 112                                 ch->logflags |= LOG_FLAG_ILLEGALSIZE;
 113                         }
 114
 115                         priv->stats.rx_dropped++;
 116                         priv->stats.rx_length_errors++;
 117                         return;
 118                 }
 119                 header->length -= LL_HEADER_LENGTH;
 120                 len -= LL_HEADER_LENGTH;
 121                 if ((header->length > skb_tailroom(pskb)) ||
 122                         (header->length > len)) {
 123                         if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 124                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 125                                         "%s(%s): Packet size %d (overrun)"
 126                                         " - dropping", CTCM_FUNTAIL,
 127                                                 dev->name, header->length);
 128                                 ch->logflags |= LOG_FLAG_OVERRUN;
 129                         }
 130
 131                         priv->stats.rx_dropped++;
 132                         priv->stats.rx_length_errors++;
 133                         return;
 134                 }
 135                 skb_put(pskb, header->length);
 136                 skb_reset_mac_header(pskb);
 137                 len -= header->length;
 138                 skb = dev_alloc_skb(pskb->len);
 139                 if (!skb) {
 140                         if (!(ch->logflags & LOG_FLAG_NOMEM)) {
 141                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 142                                         "%s(%s): MEMORY allocation error",
 143                                                 CTCM_FUNTAIL, dev->name);
 144                                 ch->logflags |= LOG_FLAG_NOMEM;
 145                         }
 146                         priv->stats.rx_dropped++;
 147                         return;
 148                 }
 149                 skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
 150                                           pskb->len);
 151                 skb_reset_mac_header(skb);
 152                 skb->dev = pskb->dev;
 153                 skb->protocol = pskb->protocol;
 154                 pskb->ip_summed = CHECKSUM_UNNECESSARY;
 155                 skblen = skb->len;
 156                 /*
 157                  * reset logflags
 158                  */
 159                 ch->logflags = 0;
 160                 priv->stats.rx_packets++;
 161                 priv->stats.rx_bytes += skblen;
 162                 netif_rx_ni(skb);
 163                 dev->last_rx = jiffies;
 164                 if (len > 0) {
 165                         skb_pull(pskb, header->length);
 166                         if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
 167                                 if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 168                                         CTCM_DBF_DEV_NAME(TRACE, dev,
 169                                                 "Overrun in ctcm_unpack_skb");
 170                                         ch->logflags |= LOG_FLAG_OVERRUN;
 171                                 }
 172                                 return;
 173                         }
 174                         skb_put(pskb, LL_HEADER_LENGTH);
 175                 }
 176         }
 177 }
 178
 179 /**
 180  * Release a specific channel in the channel list.
 181  *
 182  *  ch          Pointer to channel struct to be released.
 183  */
 184 static void channel_free(struct channel *ch)
 185 {
 186         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s)", CTCM_FUNTAIL, ch->id);
 187         ch->flags &= ~CHANNEL_FLAGS_INUSE;
 188         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
 189 }
 190
 191 /**
 192  * Remove a specific channel in the channel list.
 193  *
 194  *  ch          Pointer to channel struct to be released.
 195  */
 196 static void channel_remove(struct channel *ch)
 197 {
 198         struct channel **c = &channels;
 199         char chid[CTCM_ID_SIZE+1];
 200         int ok = 0;
 201
 202         if (ch == NULL)
 203                 return;
 204         else
 205                 strncpy(chid, ch->id, CTCM_ID_SIZE);
 206
 207         channel_free(ch);
 208         while (*c) {
 209                 if (*c == ch) {
 210                         *c = ch->next;
 211                         fsm_deltimer(&ch->timer);
 212                         if (IS_MPC(ch))
 213                                 fsm_deltimer(&ch->sweep_timer);
 214
 215                         kfree_fsm(ch->fsm);
 216                         clear_normalized_cda(&ch->ccw[4]);
 217                         if (ch->trans_skb != NULL) {
 218                                 clear_normalized_cda(&ch->ccw[1]);
 219                                 dev_kfree_skb_any(ch->trans_skb);
 220                         }
 221                         if (IS_MPC(ch)) {
 222                                 tasklet_kill(&ch->ch_tasklet);
 223                                 tasklet_kill(&ch->ch_disc_tasklet);
 224                                 kfree(ch->discontact_th);
 225                         }
 226                         kfree(ch->ccw);
 227                         kfree(ch->irb);
 228                         kfree(ch);
 229                         ok = 1;
 230                         break;
 231                 }
 232                 c = &((*c)->next);
 233         }
 234
 235         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
 236                         chid, ok ? "OK" : "failed");
 237 }
 238
 239 /**
 240  * Get a specific channel from the channel list.
 241  *
 242  *  type        Type of channel we are interested in.
 243  *  id          Id of channel we are interested in.
 244  *  direction   Direction we want to use this channel for.
 245  *
 246  * returns Pointer to a channel or NULL if no matching channel available.
 247  */
 248 static struct channel *channel_get(enum channel_types type,
 249                                         char *id, int direction)
 250 {
 251         struct channel *ch = channels;
 252
 253         while (ch && (strncmp(ch->id, id, CTCM_ID_SIZE) || (ch->type != type)))
 254                 ch = ch->next;
 255         if (!ch) {
 256                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 257                                 "%s(%d, %s, %d) not found in channel list\n",
 258                                 CTCM_FUNTAIL, type, id, direction);
 259         } else {
 260                 if (ch->flags & CHANNEL_FLAGS_INUSE)
 261                         ch = NULL;
 262                 else {
 263                         ch->flags |= CHANNEL_FLAGS_INUSE;
 264                         ch->flags &= ~CHANNEL_FLAGS_RWMASK;
 265                         ch->flags |= (direction == WRITE)
 266                             ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
 267                         fsm_newstate(ch->fsm, CTC_STATE_STOPPED);
 268                 }
 269         }
 270         return ch;
 271 }
 272
 273 static long ctcm_check_irb_error(struct ccw_device *cdev, struct irb *irb)
 274 {
 275         if (!IS_ERR(irb))
 276                 return 0;
 277
 278         CTCM_DBF_TEXT_(ERROR, CTC_DBF_WARN,
 279                         "irb error %ld on device %s\n",
 280                                 PTR_ERR(irb), cdev->dev.bus_id);
 281
 282         switch (PTR_ERR(irb)) {
 283         case -EIO:
 284                 ctcm_pr_warn("i/o-error on device %s\n", cdev->dev.bus_id);
 285                 break;
 286         case -ETIMEDOUT:
 287                 ctcm_pr_warn("timeout on device %s\n", cdev->dev.bus_id);
 288                 break;
 289         default:
 290                 ctcm_pr_warn("unknown error %ld on device %s\n",
 291                                 PTR_ERR(irb), cdev->dev.bus_id);
 292         }
 293         return PTR_ERR(irb);
 294 }
 295
 296
 297 /**
 298  * Check sense of a unit check.
 299  *
 300  *  ch          The channel, the sense code belongs to.
 301  *  sense       The sense code to inspect.
 302  */
 303 static inline void ccw_unit_check(struct channel *ch, __u8 sense)
 304 {
 305         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
 306                         "%s(%s): %02x",
 307                                 CTCM_FUNTAIL, ch->id, sense);
 308
 309         if (sense & SNS0_INTERVENTION_REQ) {
 310                 if (sense & 0x01) {
 311                         if (ch->sense_rc != 0x01) {
 312                                 ctcm_pr_debug("%s: Interface disc. or Sel. "
 313                                               "reset (remote)\n", ch->id);
 314                                 ch->sense_rc = 0x01;
 315                         }
 316                         fsm_event(ch->fsm, CTC_EVENT_UC_RCRESET, ch);
 317                 } else {
 318                         if (ch->sense_rc != SNS0_INTERVENTION_REQ) {
 319                                 ctcm_pr_debug("%s: System reset (remote)\n",
 320                                               ch->id);
 321                                 ch->sense_rc = SNS0_INTERVENTION_REQ;
 322                         }
 323                         fsm_event(ch->fsm, CTC_EVENT_UC_RSRESET, ch);
 324                 }
 325         } else if (sense & SNS0_EQUIPMENT_CHECK) {
 326                 if (sense & SNS0_BUS_OUT_CHECK) {
 327                         if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 328                                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 329                                         "%s(%s): remote HW error %02x",
 330                                                 CTCM_FUNTAIL, ch->id, sense);
 331                                 ch->sense_rc = SNS0_BUS_OUT_CHECK;
 332                         }
 333                         fsm_event(ch->fsm, CTC_EVENT_UC_HWFAIL, ch);
 334                 } else {
 335                         if (ch->sense_rc != SNS0_EQUIPMENT_CHECK) {
 336                                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 337                                         "%s(%s): remote read parity error %02x",
 338                                                 CTCM_FUNTAIL, ch->id, sense);
 339                                 ch->sense_rc = SNS0_EQUIPMENT_CHECK;
 340                         }
 341                         fsm_event(ch->fsm, CTC_EVENT_UC_RXPARITY, ch);
 342                 }
 343         } else if (sense & SNS0_BUS_OUT_CHECK) {
 344                 if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 345                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 346                                 "%s(%s): BUS OUT error %02x",
 347                                         CTCM_FUNTAIL, ch->id, sense);
 348                         ch->sense_rc = SNS0_BUS_OUT_CHECK;
 349                 }
 350                 if (sense & 0x04)       /* data-streaming timeout */
 351                         fsm_event(ch->fsm, CTC_EVENT_UC_TXTIMEOUT, ch);
 352                 else                    /* Data-transfer parity error */
 353                         fsm_event(ch->fsm, CTC_EVENT_UC_TXPARITY, ch);
 354         } else if (sense & SNS0_CMD_REJECT) {
 355                 if (ch->sense_rc != SNS0_CMD_REJECT) {
 356                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 357                                 "%s(%s): Command rejected",
 358                                                 CTCM_FUNTAIL, ch->id);
 359                         ch->sense_rc = SNS0_CMD_REJECT;
 360                 }
 361         } else if (sense == 0) {
 362                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 363                         "%s(%s): Unit check ZERO",
 364                                         CTCM_FUNTAIL, ch->id);
 365                 fsm_event(ch->fsm, CTC_EVENT_UC_ZERO, ch);
 366         } else {
 367                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 368                         "%s(%s): Unit check code %02x unknown",
 369                                         CTCM_FUNTAIL, ch->id, sense);
 370                 fsm_event(ch->fsm, CTC_EVENT_UC_UNKNOWN, ch);
 371         }
 372 }
 373
 374 int ctcm_ch_alloc_buffer(struct channel *ch)
 375 {
 376         clear_normalized_cda(&ch->ccw[1]);
 377         ch->trans_skb = __dev_alloc_skb(ch->max_bufsize, GFP_ATOMIC | GFP_DMA);
 378         if (ch->trans_skb == NULL) {
 379                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 380                         "%s(%s): %s trans_skb allocation error",
 381                         CTCM_FUNTAIL, ch->id,
 382                         (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
 383                 return -ENOMEM;
 384         }
 385
 386         ch->ccw[1].count = ch->max_bufsize;
 387         if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
 388                 dev_kfree_skb(ch->trans_skb);
 389                 ch->trans_skb = NULL;
 390                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 391                         "%s(%s): %s set norm_cda failed",
 392                         CTCM_FUNTAIL, ch->id,
 393                         (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
 394                 return -ENOMEM;
 395         }
 396
 397         ch->ccw[1].count = 0;
 398         ch->trans_skb_data = ch->trans_skb->data;
 399         ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
 400         return 0;
 401 }
 402
 403 /*
 404  * Interface API for upper network layers
 405  */
 406
 407 /**
 408  * Open an interface.
 409  * Called from generic network layer when ifconfig up is run.
 410  *
 411  *  dev         Pointer to interface struct.
 412  *
 413  * returns 0 on success, -ERRNO on failure. (Never fails.)
 414  */
 415 int ctcm_open(struct net_device *dev)
 416 {
 417         struct ctcm_priv *priv = dev->priv;
 418
 419         CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 420         if (!IS_MPC(priv))
 421                 fsm_event(priv->fsm,    DEV_EVENT_START, dev);
 422         return 0;
 423 }
 424
 425 /**
 426  * Close an interface.
 427  * Called from generic network layer when ifconfig down is run.
 428  *
 429  *  dev         Pointer to interface struct.
 430  *
 431  * returns 0 on success, -ERRNO on failure. (Never fails.)
 432  */
 433 int ctcm_close(struct net_device *dev)
 434 {
 435         struct ctcm_priv *priv = dev->priv;
 436
 437         CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 438         if (!IS_MPC(priv))
 439                 fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
 440         return 0;
 441 }
 442
 443
 444 /**
 445  * Transmit a packet.
 446  * This is a helper function for ctcm_tx().
 447  *
 448  *  ch          Channel to be used for sending.
 449  *  skb         Pointer to struct sk_buff of packet to send.
 450  *            The linklevel header has already been set up
 451  *            by ctcm_tx().
 452  *
 453  * returns 0 on success, -ERRNO on failure. (Never fails.)
 454  */
 455 static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
 456 {
 457         unsigned long saveflags;
 458         struct ll_header header;
 459         int rc = 0;
 460         __u16 block_len;
 461         int ccw_idx;
 462         struct sk_buff *nskb;
 463         unsigned long hi;
 464
 465         /* we need to acquire the lock for testing the state
 466          * otherwise we can have an IRQ changing the state to
 467          * TXIDLE after the test but before acquiring the lock.
 468          */
 469         spin_lock_irqsave(&ch->collect_lock, saveflags);
 470         if (fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) {
 471                 int l = skb->len + LL_HEADER_LENGTH;
 472
 473                 if (ch->collect_len + l > ch->max_bufsize - 2) {
 474                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 475                         return -EBUSY;
 476                 } else {
 477                         atomic_inc(&skb->users);
 478                         header.length = l;
 479                         header.type = skb->protocol;
 480                         header.unused = 0;
 481                         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
 482                                LL_HEADER_LENGTH);
 483                         skb_queue_tail(&ch->collect_queue, skb);
 484                         ch->collect_len += l;
 485                 }
 486                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 487                                 goto done;
 488         }
 489         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 490         /*
 491          * Protect skb against beeing free'd by upper
 492          * layers.
 493          */
 494         atomic_inc(&skb->users);
 495         ch->prof.txlen += skb->len;
 496         header.length = skb->len + LL_HEADER_LENGTH;
 497         header.type = skb->protocol;
 498         header.unused = 0;
 499         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header, LL_HEADER_LENGTH);
 500         block_len = skb->len + 2;
 501         *((__u16 *)skb_push(skb, 2)) = block_len;
 502
 503         /*
 504          * IDAL support in CTCM is broken, so we have to
 505          * care about skb's above 2G ourselves.
 506          */
 507         hi = ((unsigned long)skb_tail_pointer(skb) + LL_HEADER_LENGTH) >> 31;
 508         if (hi) {
 509                 nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 510                 if (!nskb) {
 511                         atomic_dec(&skb->users);
 512                         skb_pull(skb, LL_HEADER_LENGTH + 2);
 513                         ctcm_clear_busy(ch->netdev);
 514                         return -ENOMEM;
 515                 } else {
 516                         memcpy(skb_put(nskb, skb->len), skb->data, skb->len);
 517                         atomic_inc(&nskb->users);
 518                         atomic_dec(&skb->users);
 519                         dev_kfree_skb_irq(skb);
 520                         skb = nskb;
 521                 }
 522         }
 523
 524         ch->ccw[4].count = block_len;
 525         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 526                 /*
 527                  * idal allocation failed, try via copying to
 528                  * trans_skb. trans_skb usually has a pre-allocated
 529                  * idal.
 530                  */
 531                 if (ctcm_checkalloc_buffer(ch)) {
 532                         /*
 533                          * Remove our header. It gets added
 534                          * again on retransmit.
 535                          */
 536                         atomic_dec(&skb->users);
 537                         skb_pull(skb, LL_HEADER_LENGTH + 2);
 538                         ctcm_clear_busy(ch->netdev);
 539                         return -ENOMEM;
 540                 }
 541
 542                 skb_reset_tail_pointer(ch->trans_skb);
 543                 ch->trans_skb->len = 0;
 544                 ch->ccw[1].count = skb->len;
 545                 skb_copy_from_linear_data(skb,
 546                                 skb_put(ch->trans_skb, skb->len), skb->len);
 547                 atomic_dec(&skb->users);
 548                 dev_kfree_skb_irq(skb);
 549                 ccw_idx = 0;
 550         } else {
 551                 skb_queue_tail(&ch->io_queue, skb);
 552                 ccw_idx = 3;
 553         }
 554         ch->retry = 0;
 555         fsm_newstate(ch->fsm, CTC_STATE_TX);
 556         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 557         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 558         ch->prof.send_stamp = current_kernel_time(); /* xtime */
 559         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx],
 560                                         (unsigned long)ch, 0xff, 0);
 561         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 562         if (ccw_idx == 3)
 563                 ch->prof.doios_single++;
 564         if (rc != 0) {
 565                 fsm_deltimer(&ch->timer);
 566                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
 567                 if (ccw_idx == 3)
 568                         skb_dequeue_tail(&ch->io_queue);
 569                 /*
 570                  * Remove our header. It gets added
 571                  * again on retransmit.
 572                  */
 573                 skb_pull(skb, LL_HEADER_LENGTH + 2);
 574         } else if (ccw_idx == 0) {
 575                 struct net_device *dev = ch->netdev;
 576                 struct ctcm_priv *priv = dev->priv;
 577                 priv->stats.tx_packets++;
 578                 priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 579         }
 580 done:
 581         ctcm_clear_busy(ch->netdev);
 582         return rc;
 583 }
 584
 585 static void ctcmpc_send_sweep_req(struct channel *rch)
 586 {
 587         struct net_device *dev = rch->netdev;
 588         struct ctcm_priv *priv;
 589         struct mpc_group *grp;
 590         struct th_sweep *header;
 591         struct sk_buff *sweep_skb;
 592         struct channel *ch;
 593         /* int rc = 0; */
 594
 595         priv = dev->priv;
 596         grp = priv->mpcg;
 597         ch = priv->channel[WRITE];
 598
 599         /* sweep processing is not complete until response and request */
 600         /* has completed for all read channels in group                */
 601         if (grp->in_sweep == 0) {
 602                 grp->in_sweep = 1;
 603                 grp->sweep_rsp_pend_num = grp->active_channels[READ];
 604                 grp->sweep_req_pend_num = grp->active_channels[READ];
 605         }
 606
 607         sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
 608
 609         if (sweep_skb == NULL)  {
 610                 /* rc = -ENOMEM; */
 611                                 goto nomem;
 612         }
 613
 614         header = kmalloc(TH_SWEEP_LENGTH, gfp_type());
 615
 616         if (!header) {
 617                 dev_kfree_skb_any(sweep_skb);
 618                 /* rc = -ENOMEM; */
 619                                 goto nomem;
 620         }
 621
 622         header->th.th_seg       = 0x00 ;
 623         header->th.th_ch_flag   = TH_SWEEP_REQ;  /* 0x0f */
 624         header->th.th_blk_flag  = 0x00;
 625         header->th.th_is_xid    = 0x00;
 626         header->th.th_seq_num   = 0x00;
 627         header->sw.th_last_seq  = ch->th_seq_num;
 628
 629         memcpy(skb_put(sweep_skb, TH_SWEEP_LENGTH), header, TH_SWEEP_LENGTH);
 630
 631         kfree(header);
 632
 633         dev->trans_start = jiffies;
 634         skb_queue_tail(&ch->sweep_queue, sweep_skb);
 635
 636         fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
 637
 638         return;
 639
 640 nomem:
 641         grp->in_sweep = 0;
 642         ctcm_clear_busy(dev);
 643         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 644
 645         return;
 646 }
 647
 648 /*
 649  * MPC mode version of transmit_skb
 650  */
 651 static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
 652 {
 653         struct pdu *p_header;
 654         struct net_device *dev = ch->netdev;
 655         struct ctcm_priv *priv = dev->priv;
 656         struct mpc_group *grp = priv->mpcg;
 657         struct th_header *header;
 658         struct sk_buff *nskb;
 659         int rc = 0;
 660         int ccw_idx;
 661         unsigned long hi;
 662         unsigned long saveflags = 0;    /* avoids compiler warning */
 663         __u16 block_len;
 664
 665         CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
 666                         __func__, dev->name, smp_processor_id(), ch,
 667                                         ch->id, fsm_getstate_str(ch->fsm));
 668
 669         if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
 670                 spin_lock_irqsave(&ch->collect_lock, saveflags);
 671                 atomic_inc(&skb->users);
 672                 p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
 673
 674                 if (!p_header) {
 675                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 676                                 goto nomem_exit;
 677                 }
 678
 679                 p_header->pdu_offset = skb->len;
 680                 p_header->pdu_proto = 0x01;
 681                 p_header->pdu_flag = 0x00;
 682                 if (skb->protocol == ntohs(ETH_P_SNAP)) {
 683                         p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
 684                 } else {
 685                         p_header->pdu_flag |= PDU_FIRST;
 686                 }
 687                 p_header->pdu_seq = 0;
 688                 memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header,
 689                        PDU_HEADER_LENGTH);
 690
 691                 CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
 692                                 "pdu header and data for up to 32 bytes:\n",
 693                                 __func__, dev->name, skb->len);
 694                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 695
 696                 skb_queue_tail(&ch->collect_queue, skb);
 697                 ch->collect_len += skb->len;
 698                 kfree(p_header);
 699
 700                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 701                         goto done;
 702         }
 703
 704         /*
 705          * Protect skb against beeing free'd by upper
 706          * layers.
 707          */
 708         atomic_inc(&skb->users);
 709
 710         block_len = skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 711         /*
 712          * IDAL support in CTCM is broken, so we have to
 713          * care about skb's above 2G ourselves.
 714          */
 715         hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
 716         if (hi) {
 717                 nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 718                 if (!nskb) {
 719                         goto nomem_exit;
 720                 } else {
 721                         memcpy(skb_put(nskb, skb->len), skb->data, skb->len);
 722                         atomic_inc(&nskb->users);
 723                         atomic_dec(&skb->users);
 724                         dev_kfree_skb_irq(skb);
 725                         skb = nskb;
 726                 }
 727         }
 728
 729         p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
 730
 731         if (!p_header)
 732                 goto nomem_exit;
 733
 734         p_header->pdu_offset = skb->len;
 735         p_header->pdu_proto = 0x01;
 736         p_header->pdu_flag = 0x00;
 737         p_header->pdu_seq = 0;
 738         if (skb->protocol == ntohs(ETH_P_SNAP)) {
 739                 p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
 740         } else {
 741                 p_header->pdu_flag |= PDU_FIRST;
 742         }
 743         memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header, PDU_HEADER_LENGTH);
 744
 745         kfree(p_header);
 746
 747         if (ch->collect_len > 0) {
 748                 spin_lock_irqsave(&ch->collect_lock, saveflags);
 749                 skb_queue_tail(&ch->collect_queue, skb);
 750                 ch->collect_len += skb->len;
 751                 skb = skb_dequeue(&ch->collect_queue);
 752                 ch->collect_len -= skb->len;
 753                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 754         }
 755
 756         p_header = (struct pdu *)skb->data;
 757         p_header->pdu_flag |= PDU_LAST;
 758
 759         ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
 760
 761         header = kmalloc(TH_HEADER_LENGTH, gfp_type());
 762         if (!header)
 763                 goto nomem_exit;
 764
 765         header->th_seg = 0x00;
 766         header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
 767         header->th_blk_flag = 0x00;
 768         header->th_is_xid = 0x00;          /* Just data here */
 769         ch->th_seq_num++;
 770         header->th_seq_num = ch->th_seq_num;
 771
 772         CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
 773                        __func__, dev->name, ch->th_seq_num);
 774
 775         /* put the TH on the packet */
 776         memcpy(skb_push(skb, TH_HEADER_LENGTH), header, TH_HEADER_LENGTH);
 777
 778         kfree(header);
 779
 780         CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
 781                         "up to 32 bytes sent to vtam:\n",
 782                                 __func__, dev->name, skb->len);
 783         CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 784
 785         ch->ccw[4].count = skb->len;
 786         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 787                 /*
 788                  * idal allocation failed, try via copying to trans_skb.
 789                  * trans_skb usually has a pre-allocated idal.
 790                  */
 791                 if (ctcm_checkalloc_buffer(ch)) {
 792                         /*
 793                          * Remove our header.
 794                          * It gets added again on retransmit.
 795                          */
 796                                 goto nomem_exit;
 797                 }
 798
 799                 skb_reset_tail_pointer(ch->trans_skb);
 800                 ch->trans_skb->len = 0;
 801                 ch->ccw[1].count = skb->len;
 802                 memcpy(skb_put(ch->trans_skb, skb->len), skb->data, skb->len);
 803                 atomic_dec(&skb->users);
 804                 dev_kfree_skb_irq(skb);
 805                 ccw_idx = 0;
 806                 CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
 807                                 "up to 32 bytes sent to vtam:\n",
 808                                 __func__, dev->name, ch->trans_skb->len);
 809                 CTCM_D3_DUMP((char *)ch->trans_skb->data,
 810                                 min_t(int, 32, ch->trans_skb->len));
 811         } else {
 812                 skb_queue_tail(&ch->io_queue, skb);
 813                 ccw_idx = 3;
 814         }
 815         ch->retry = 0;
 816         fsm_newstate(ch->fsm, CTC_STATE_TX);
 817         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 818
 819         if (do_debug_ccw)
 820                 ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 821                                         sizeof(struct ccw1) * 3);
 822
 823         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 824         ch->prof.send_stamp = current_kernel_time(); /* xtime */
 825         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx],
 826                                         (unsigned long)ch, 0xff, 0);
 827         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 828         if (ccw_idx == 3)
 829                 ch->prof.doios_single++;
 830         if (rc != 0) {
 831                 fsm_deltimer(&ch->timer);
 832                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
 833                 if (ccw_idx == 3)
 834                         skb_dequeue_tail(&ch->io_queue);
 835         } else if (ccw_idx == 0) {
 836                 priv->stats.tx_packets++;
 837                 priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
 838         }
 839         if (ch->th_seq_num > 0xf0000000)        /* Chose at random. */
 840                 ctcmpc_send_sweep_req(ch);
 841
 842         goto done;
 843 nomem_exit:
 844         CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
 845                         "%s(%s): MEMORY allocation ERROR\n",
 846                         CTCM_FUNTAIL, ch->id);
 847         rc = -ENOMEM;
 848         atomic_dec(&skb->users);
 849         dev_kfree_skb_any(skb);
 850         fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
 851 done:
 852         CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
 853         return rc;
 854 }
 855
 856 /**
 857  * Start transmission of a packet.
 858  * Called from generic network device layer.
 859  *
 860  *  skb         Pointer to buffer containing the packet.
 861  *  dev         Pointer to interface struct.
 862  *
 863  * returns 0 if packet consumed, !0 if packet rejected.
 864  *         Note: If we return !0, then the packet is free'd by
 865  *               the generic network layer.
 866  */
 867 /* first merge version - leaving both functions separated */
 868 static int ctcm_tx(struct sk_buff *skb, struct net_device *dev)
 869 {
 870         struct ctcm_priv *priv = dev->priv;
 871
 872         if (skb == NULL) {
 873                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 874                                 "%s(%s): NULL sk_buff passed",
 875                                         CTCM_FUNTAIL, dev->name);
 876                 priv->stats.tx_dropped++;
 877                 return 0;
 878         }
 879         if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
 880                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 881                         "%s(%s): Got sk_buff with head room < %ld bytes",
 882                         CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
 883                 dev_kfree_skb(skb);
 884                 priv->stats.tx_dropped++;
 885                 return 0;
 886         }
 887
 888         /*
 889          * If channels are not running, try to restart them
 890          * and throw away packet.
 891          */
 892         if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
 893                 fsm_event(priv->fsm, DEV_EVENT_START, dev);
 894                 dev_kfree_skb(skb);
 895                 priv->stats.tx_dropped++;
 896                 priv->stats.tx_errors++;
 897                 priv->stats.tx_carrier_errors++;
 898                 return 0;
 899         }
 900
 901         if (ctcm_test_and_set_busy(dev))
 902                 return -EBUSY;
 903
 904         dev->trans_start = jiffies;
 905         if (ctcm_transmit_skb(priv->channel[WRITE], skb) != 0)
 906                 return 1;
 907         return 0;
 908 }
 909
 910 /* unmerged MPC variant of ctcm_tx */
 911 static int ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
 912 {
 913         int len = 0;
 914         struct ctcm_priv *priv = dev->priv;
 915         struct mpc_group *grp  = priv->mpcg;
 916         struct sk_buff *newskb = NULL;
 917
 918         /*
 919          * Some sanity checks ...
 920          */
 921         if (skb == NULL) {
 922                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 923                         "%s(%s): NULL sk_buff passed",
 924                                         CTCM_FUNTAIL, dev->name);
 925                 priv->stats.tx_dropped++;
 926                                         goto done;
 927         }
 928         if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
 929                 CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 930                         "%s(%s): Got sk_buff with head room < %ld bytes",
 931                         CTCM_FUNTAIL, dev->name,
 932                                 TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 933
 934                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 935
 936                 len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 937                 newskb = __dev_alloc_skb(len, gfp_type() | GFP_DMA);
 938
 939                 if (!newskb) {
 940                         CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 941                                 "%s: %s: __dev_alloc_skb failed",
 942                                                 __func__, dev->name);
 943
 944                         dev_kfree_skb_any(skb);
 945                         priv->stats.tx_dropped++;
 946                         priv->stats.tx_errors++;
 947                         priv->stats.tx_carrier_errors++;
 948                         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 949                                         goto done;
 950                 }
 951                 newskb->protocol = skb->protocol;
 952                 skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 953                 memcpy(skb_put(newskb, skb->len), skb->data, skb->len);
 954                 dev_kfree_skb_any(skb);
 955                 skb = newskb;
 956         }
 957
 958         /*
 959          * If channels are not running,
 960          * notify anybody about a link failure and throw
 961          * away packet.
 962          */
 963         if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
 964            (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
 965                 dev_kfree_skb_any(skb);
 966                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 967                         "%s(%s): inactive MPCGROUP - dropped",
 968                                         CTCM_FUNTAIL, dev->name);
 969                 priv->stats.tx_dropped++;
 970                 priv->stats.tx_errors++;
 971                 priv->stats.tx_carrier_errors++;
 972                                         goto done;
 973         }
 974
 975         if (ctcm_test_and_set_busy(dev)) {
 976                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 977                         "%s(%s): device busy - dropped",
 978                                         CTCM_FUNTAIL, dev->name);
 979                 dev_kfree_skb_any(skb);
 980                 priv->stats.tx_dropped++;
 981                 priv->stats.tx_errors++;
 982                 priv->stats.tx_carrier_errors++;
 983                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 984                                         goto done;
 985         }
 986
 987         dev->trans_start = jiffies;
 988         if (ctcmpc_transmit_skb(priv->channel[WRITE], skb) != 0) {
 989                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 990                         "%s(%s): device error - dropped",
 991                                         CTCM_FUNTAIL, dev->name);
 992                 dev_kfree_skb_any(skb);
 993                 priv->stats.tx_dropped++;
 994                 priv->stats.tx_errors++;
 995                 priv->stats.tx_carrier_errors++;
 996                 ctcm_clear_busy(dev);
 997                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 998                                         goto done;
 999         }
1000         ctcm_clear_busy(dev);
1001 done:
1002         if (do_debug)
1003                 MPC_DBF_DEV_NAME(TRACE, dev, "exit");
1004
1005         return 0;       /* handle freeing of skb here */
1006 }
1007
1008
1009 /**
1010  * Sets MTU of an interface.
1011  *
1012  *  dev         Pointer to interface struct.
1013  *  new_mtu     The new MTU to use for this interface.
1014  *
1015  * returns 0 on success, -EINVAL if MTU is out of valid range.
1016  *         (valid range is 576 .. 65527). If VM is on the
1017  *         remote side, maximum MTU is 32760, however this is
1018  *         not checked here.
1019  */
1020 static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
1021 {
1022         struct ctcm_priv *priv;
1023         int max_bufsize;
1024
1025         if (new_mtu < 576 || new_mtu > 65527)
1026                 return -EINVAL;
1027
1028         priv = dev->priv;
1029         max_bufsize = priv->channel[READ]->max_bufsize;
1030
1031         if (IS_MPC(priv)) {
1032                 if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
1033                         return -EINVAL;
1034                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1035         } else {
1036                 if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
1037                         return -EINVAL;
1038                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1039         }
1040         dev->mtu = new_mtu;
1041         return 0;
1042 }
1043
1044 /**
1045  * Returns interface statistics of a device.
1046  *
1047  *  dev         Pointer to interface struct.
1048  *
1049  * returns Pointer to stats struct of this interface.
1050  */
1051 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1052 {
1053         return &((struct ctcm_priv *)dev->priv)->stats;
1054 }
1055
1056 static void ctcm_free_netdevice(struct net_device *dev)
1057 {
1058         struct ctcm_priv *priv;
1059         struct mpc_group *grp;
1060
1061         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1062                         "%s(%s)", CTCM_FUNTAIL, dev->name);
1063         priv = dev->priv;
1064         if (priv) {
1065                 grp = priv->mpcg;
1066                 if (grp) {
1067                         if (grp->fsm)
1068                                 kfree_fsm(grp->fsm);
1069                         if (grp->xid_skb)
1070                                 dev_kfree_skb(grp->xid_skb);
1071                         if (grp->rcvd_xid_skb)
1072                                 dev_kfree_skb(grp->rcvd_xid_skb);
1073                         tasklet_kill(&grp->mpc_tasklet2);
1074                         kfree(grp);
1075                         priv->mpcg = NULL;
1076                 }
1077                 if (priv->fsm) {
1078                         kfree_fsm(priv->fsm);
1079                         priv->fsm = NULL;
1080                 }
1081                 kfree(priv->xid);
1082                 priv->xid = NULL;
1083         /*
1084          * Note: kfree(priv); is done in "opposite" function of
1085          * allocator function probe_device which is remove_device.
1086          */
1087         }
1088 #ifdef MODULE
1089         free_netdev(dev);
1090 #endif
1091 }
1092
1093 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1094
1095 void static ctcm_dev_setup(struct net_device *dev)
1096 {
1097         dev->open = ctcm_open;
1098         dev->stop = ctcm_close;
1099         dev->get_stats = ctcm_stats;
1100         dev->change_mtu = ctcm_change_mtu;
1101         dev->type = ARPHRD_SLIP;
1102         dev->tx_queue_len = 100;
1103         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1104 }
1105
1106 /*
1107  * Initialize everything of the net device except the name and the
1108  * channel structs.
1109  */
1110 static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1111 {
1112         struct net_device *dev;
1113         struct mpc_group *grp;
1114         if (!priv)
1115                 return NULL;
1116
1117         if (IS_MPC(priv))
1118                 dev = alloc_netdev(0, MPC_DEVICE_GENE, ctcm_dev_setup);
1119         else
1120                 dev = alloc_netdev(0, CTC_DEVICE_GENE, ctcm_dev_setup);
1121
1122         if (!dev) {
1123                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1124                         "%s: MEMORY allocation ERROR",
1125                         CTCM_FUNTAIL);
1126                 return NULL;
1127         }
1128         dev->priv = priv;
1129         priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1130                                 CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1131                                 dev_fsm, dev_fsm_len, GFP_KERNEL);
1132         if (priv->fsm == NULL) {
1133                 CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1134                 kfree(dev);
1135                 return NULL;
1136         }
1137         fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1138         fsm_settimer(priv->fsm, &priv->restart_timer);
1139
1140         if (IS_MPC(priv)) {
1141                 /*  MPC Group Initializations  */
1142                 grp = ctcmpc_init_mpc_group(priv);
1143                 if (grp == NULL) {
1144                         MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1145                         kfree(dev);
1146                         return NULL;
1147                 }
1148                 tasklet_init(&grp->mpc_tasklet2,
1149                                 mpc_group_ready, (unsigned long)dev);
1150                 dev->mtu = MPC_BUFSIZE_DEFAULT -
1151                                 TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1152
1153                 dev->hard_start_xmit = ctcmpc_tx;
1154                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1155                 priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1156         } else {
1157                 dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1158                 dev->hard_start_xmit = ctcm_tx;
1159                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1160         }
1161
1162         CTCMY_DBF_DEV(SETUP, dev, "finished");
1163
1164         return dev;
1165 }
1166
1167 /**
1168  * Main IRQ handler.
1169  *
1170  *  cdev        The ccw_device the interrupt is for.
1171  *  intparm     interruption parameter.
1172  *  irb         interruption response block.
1173  */
1174 static void ctcm_irq_handler(struct ccw_device *cdev,
1175                                 unsigned long intparm, struct irb *irb)
1176 {
1177         struct channel          *ch;
1178         struct net_device       *dev;
1179         struct ctcm_priv        *priv;
1180         struct ccwgroup_device  *cgdev;
1181         int cstat;
1182         int dstat;
1183
1184         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1185                 "Enter %s(%s)", CTCM_FUNTAIL, &cdev->dev.bus_id);
1186
1187         if (ctcm_check_irb_error(cdev, irb))
1188                 return;
1189
1190         cgdev = dev_get_drvdata(&cdev->dev);
1191
1192         cstat = irb->scsw.cmd.cstat;
1193         dstat = irb->scsw.cmd.dstat;
1194
1195         /* Check for unsolicited interrupts. */
1196         if (cgdev == NULL) {
1197                 ctcm_pr_warn("ctcm: Got unsolicited irq: c-%02x d-%02x\n",
1198                              cstat, dstat);
1199                 return;
1200         }
1201
1202         priv = dev_get_drvdata(&cgdev->dev);
1203
1204         /* Try to extract channel from driver data. */
1205         if (priv->channel[READ]->cdev == cdev)
1206                 ch = priv->channel[READ];
1207         else if (priv->channel[WRITE]->cdev == cdev)
1208                 ch = priv->channel[WRITE];
1209         else {
1210                 ctcm_pr_err("ctcm: Can't determine channel for interrupt, "
1211                            "device %s\n", cdev->dev.bus_id);
1212                 return;
1213         }
1214
1215         dev = ch->netdev;
1216         if (dev == NULL) {
1217                 ctcm_pr_crit("ctcm: %s dev=NULL bus_id=%s, ch=0x%p\n",
1218                                 __func__, cdev->dev.bus_id, ch);
1219                 return;
1220         }
1221
1222         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1223                 "%s(%s): int. for %s: cstat=%02x dstat=%02x",
1224                         CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1225
1226         /* Copy interruption response block. */
1227         memcpy(ch->irb, irb, sizeof(struct irb));
1228
1229         if (irb->scsw.cmd.cstat) {
1230         /* Check for good subchannel return code, otherwise error message */
1231                 fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1232                 ctcm_pr_warn("%s: subchannel check for dev: %s - %02x %02x\n",
1233                             dev->name, ch->id, irb->scsw.cmd.cstat,
1234                             irb->scsw.cmd.dstat);
1235                 return;
1236         }
1237
1238         /* Check the reason-code of a unit check */
1239         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1240                 if ((irb->ecw[0] & ch->sense_rc) == 0)
1241                         /* print it only once */
1242                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_INFO,
1243                                 "%s(%s): sense=%02x, ds=%02x",
1244                                 CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1245                 ccw_unit_check(ch, irb->ecw[0]);
1246                 return;
1247         }
1248         if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1249                 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1250                         fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1251                 else
1252                         fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1253                 return;
1254         }
1255         if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1256                 fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1257                 return;
1258         }
1259         if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1260             (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1261             (irb->scsw.cmd.stctl ==
1262              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1263                 fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1264         else
1265                 fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1266
1267 }
1268
1269 /**
1270  * Add ctcm specific attributes.
1271  * Add ctcm private data.
1272  *
1273  *  cgdev       pointer to ccwgroup_device just added
1274  *
1275  * returns 0 on success, !0 on failure.
1276  */
1277 static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1278 {
1279         struct ctcm_priv *priv;
1280         int rc;
1281
1282         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1283                         "%s %p",
1284                         __func__, cgdev);
1285
1286         if (!get_device(&cgdev->dev))
1287                 return -ENODEV;
1288
1289         priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1290         if (!priv) {
1291                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1292                         "%s: memory allocation failure",
1293                         CTCM_FUNTAIL);
1294                 put_device(&cgdev->dev);
1295                 return -ENOMEM;
1296         }
1297
1298         rc = ctcm_add_files(&cgdev->dev);
1299         if (rc) {
1300                 kfree(priv);
1301                 put_device(&cgdev->dev);
1302                 return rc;
1303         }
1304         priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1305         cgdev->cdev[0]->handler = ctcm_irq_handler;
1306         cgdev->cdev[1]->handler = ctcm_irq_handler;
1307         dev_set_drvdata(&cgdev->dev, priv);
1308
1309         return 0;
1310 }
1311
1312 /**
1313  * Add a new channel to the list of channels.
1314  * Keeps the channel list sorted.
1315  *
1316  *  cdev        The ccw_device to be added.
1317  *  type        The type class of the new channel.
1318  *  priv        Points to the private data of the ccwgroup_device.
1319  *
1320  * returns 0 on success, !0 on error.
1321  */
1322 static int add_channel(struct ccw_device *cdev, enum channel_types type,
1323                                 struct ctcm_priv *priv)
1324 {
1325         struct channel **c = &channels;
1326         struct channel *ch;
1327         int ccw_num;
1328         int rc = 0;
1329
1330         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1331                 "%s(%s), type %d, proto %d",
1332                         __func__, cdev->dev.bus_id,     type, priv->protocol);
1333
1334         ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1335         if (ch == NULL)
1336                 return -ENOMEM;
1337
1338         ch->protocol = priv->protocol;
1339         if (IS_MPC(priv)) {
1340                 ch->discontact_th = (struct th_header *)
1341                                 kzalloc(TH_HEADER_LENGTH, gfp_type());
1342                 if (ch->discontact_th == NULL)
1343                                         goto nomem_return;
1344
1345                 ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1346                 tasklet_init(&ch->ch_disc_tasklet,
1347                         mpc_action_send_discontact, (unsigned long)ch);
1348
1349                 tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1350                 ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1351                 ccw_num = 17;
1352         } else
1353                 ccw_num = 8;
1354
1355         ch->ccw = (struct ccw1 *)
1356                 kzalloc(ccw_num * sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1357         if (ch->ccw == NULL)
1358                                         goto nomem_return;
1359
1360         ch->cdev = cdev;
1361         snprintf(ch->id, CTCM_ID_SIZE, "ch-%s", cdev->dev.bus_id);
1362         ch->type = type;
1363
1364         /**
1365          * "static" ccws are used in the following way:
1366          *
1367          * ccw[0..2] (Channel program for generic I/O):
1368          *           0: prepare
1369          *           1: read or write (depending on direction) with fixed
1370          *              buffer (idal allocated once when buffer is allocated)
1371          *           2: nop
1372          * ccw[3..5] (Channel program for direct write of packets)
1373          *           3: prepare
1374          *           4: write (idal allocated on every write).
1375          *           5: nop
1376          * ccw[6..7] (Channel program for initial channel setup):
1377          *           6: set extended mode
1378          *           7: nop
1379          *
1380          * ch->ccw[0..5] are initialized in ch_action_start because
1381          * the channel's direction is yet unknown here.
1382          *
1383          * ccws used for xid2 negotiations
1384          *  ch-ccw[8-14] need to be used for the XID exchange either
1385          *    X side XID2 Processing
1386          *       8:  write control
1387          *       9:  write th
1388          *           10: write XID
1389          *           11: read th from secondary
1390          *           12: read XID   from secondary
1391          *           13: read 4 byte ID
1392          *           14: nop
1393          *    Y side XID Processing
1394          *           8:  sense
1395          *       9:  read th
1396          *           10: read XID
1397          *           11: write th
1398          *           12: write XID
1399          *           13: write 4 byte ID
1400          *           14: nop
1401          *
1402          *  ccws used for double noop due to VM timing issues
1403          *  which result in unrecoverable Busy on channel
1404          *       15: nop
1405          *       16: nop
1406          */
1407         ch->ccw[6].cmd_code     = CCW_CMD_SET_EXTENDED;
1408         ch->ccw[6].flags        = CCW_FLAG_SLI;
1409
1410         ch->ccw[7].cmd_code     = CCW_CMD_NOOP;
1411         ch->ccw[7].flags        = CCW_FLAG_SLI;
1412
1413         if (IS_MPC(priv)) {
1414                 ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1415                 ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1416                 ch->ccw[15].count    = TH_HEADER_LENGTH;
1417                 ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1418
1419                 ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1420                 ch->ccw[16].flags    = CCW_FLAG_SLI;
1421
1422                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1423                                 ctc_ch_event_names, CTC_MPC_NR_STATES,
1424                                 CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1425                                 mpc_ch_fsm_len, GFP_KERNEL);
1426         } else {
1427                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1428                                 ctc_ch_event_names, CTC_NR_STATES,
1429                                 CTC_NR_EVENTS, ch_fsm,
1430                                 ch_fsm_len, GFP_KERNEL);
1431         }
1432         if (ch->fsm == NULL)
1433                                 goto free_return;
1434
1435         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1436
1437         ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1438         if (ch->irb == NULL)
1439                                 goto nomem_return;
1440
1441         while (*c && ctcm_less_than((*c)->id, ch->id))
1442                 c = &(*c)->next;
1443
1444         if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1445                 CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1446                                 "%s (%s) already in list, using old entry",
1447                                 __func__, (*c)->id);
1448
1449                                 goto free_return;
1450         }
1451
1452         spin_lock_init(&ch->collect_lock);
1453
1454         fsm_settimer(ch->fsm, &ch->timer);
1455         skb_queue_head_init(&ch->io_queue);
1456         skb_queue_head_init(&ch->collect_queue);
1457
1458         if (IS_MPC(priv)) {
1459                 fsm_settimer(ch->fsm, &ch->sweep_timer);
1460                 skb_queue_head_init(&ch->sweep_queue);
1461         }
1462         ch->next = *c;
1463         *c = ch;
1464         return 0;
1465
1466 nomem_return:
1467         rc = -ENOMEM;
1468
1469 free_return:    /* note that all channel pointers are 0 or valid */
1470         kfree(ch->ccw);
1471         kfree(ch->discontact_th);
1472         kfree_fsm(ch->fsm);
1473         kfree(ch->irb);
1474         kfree(ch);
1475         return rc;
1476 }
1477
1478 /*
1479  * Return type of a detected device.
1480  */
1481 static enum channel_types get_channel_type(struct ccw_device_id *id)
1482 {
1483         enum channel_types type;
1484         type = (enum channel_types)id->driver_info;
1485
1486         if (type == channel_type_ficon)
1487                 type = channel_type_escon;
1488
1489         return type;
1490 }
1491
1492 /**
1493  *
1494  * Setup an interface.
1495  *
1496  *  cgdev       Device to be setup.
1497  *
1498  * returns 0 on success, !0 on failure.
1499  */
1500 static int ctcm_new_device(struct ccwgroup_device *cgdev)
1501 {
1502         char read_id[CTCM_ID_SIZE];
1503         char write_id[CTCM_ID_SIZE];
1504         int direction;
1505         enum channel_types type;
1506         struct ctcm_priv *priv;
1507         struct net_device *dev;
1508         struct ccw_device *cdev0;
1509         struct ccw_device *cdev1;
1510         int ret;
1511
1512         priv = dev_get_drvdata(&cgdev->dev);
1513         if (!priv)
1514                 return -ENODEV;
1515
1516         cdev0 = cgdev->cdev[0];
1517         cdev1 = cgdev->cdev[1];
1518
1519         type = get_channel_type(&cdev0->id);
1520
1521         snprintf(read_id, CTCM_ID_SIZE, "ch-%s", cdev0->dev.bus_id);
1522         snprintf(write_id, CTCM_ID_SIZE, "ch-%s", cdev1->dev.bus_id);
1523
1524         ret = add_channel(cdev0, type, priv);
1525         if (ret)
1526                 return ret;
1527         ret = add_channel(cdev1, type, priv);
1528         if (ret)
1529                 return ret;
1530
1531         ret = ccw_device_set_online(cdev0);
1532         if (ret != 0) {
1533                 /* may be ok to fail now - can be done later */
1534                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1535                         "%s(%s) set_online rc=%d",
1536                                 CTCM_FUNTAIL, read_id, ret);
1537         }
1538
1539         ret = ccw_device_set_online(cdev1);
1540         if (ret != 0) {
1541                 /* may be ok to fail now - can be done later */
1542                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1543                         "%s(%s) set_online rc=%d",
1544                                 CTCM_FUNTAIL, write_id, ret);
1545         }
1546
1547         dev = ctcm_init_netdevice(priv);
1548         if (dev == NULL)
1549                         goto out;
1550
1551         for (direction = READ; direction <= WRITE; direction++) {
1552                 priv->channel[direction] =
1553                     channel_get(type, direction == READ ? read_id : write_id,
1554                                 direction);
1555                 if (priv->channel[direction] == NULL) {
1556                         if (direction == WRITE)
1557                                 channel_free(priv->channel[READ]);
1558                         goto out_dev;
1559                 }
1560                 priv->channel[direction]->netdev = dev;
1561                 priv->channel[direction]->protocol = priv->protocol;
1562                 priv->channel[direction]->max_bufsize = priv->buffer_size;
1563         }
1564         /* sysfs magic */
1565         SET_NETDEV_DEV(dev, &cgdev->dev);
1566
1567         if (register_netdev(dev))
1568                         goto out_dev;
1569
1570         if (ctcm_add_attributes(&cgdev->dev)) {
1571                 unregister_netdev(dev);
1572                         goto out_dev;
1573         }
1574
1575         strlcpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1576
1577         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1578                 "setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1579                         priv->channel[READ]->id,
1580                         priv->channel[WRITE]->id, priv->protocol);
1581
1582         return 0;
1583 out_dev:
1584         ctcm_free_netdevice(dev);
1585 out:
1586         ccw_device_set_offline(cgdev->cdev[1]);
1587         ccw_device_set_offline(cgdev->cdev[0]);
1588
1589         return -ENODEV;
1590 }
1591
1592 /**
1593  * Shutdown an interface.
1594  *
1595  *  cgdev       Device to be shut down.
1596  *
1597  * returns 0 on success, !0 on failure.
1598  */
1599 static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1600 {
1601         struct ctcm_priv *priv;
1602         struct net_device *dev;
1603
1604         priv = dev_get_drvdata(&cgdev->dev);
1605         if (!priv)
1606                 return -ENODEV;
1607
1608         if (priv->channel[READ]) {
1609                 dev = priv->channel[READ]->netdev;
1610                 CTCM_DBF_DEV(SETUP, dev, "");
1611                 /* Close the device */
1612                 ctcm_close(dev);
1613                 dev->flags &= ~IFF_RUNNING;
1614                 ctcm_remove_attributes(&cgdev->dev);
1615                 channel_free(priv->channel[READ]);
1616         } else
1617                 dev = NULL;
1618
1619         if (priv->channel[WRITE])
1620                 channel_free(priv->channel[WRITE]);
1621
1622         if (dev) {
1623                 unregister_netdev(dev);
1624                 ctcm_free_netdevice(dev);
1625         }
1626
1627         if (priv->fsm)
1628                 kfree_fsm(priv->fsm);
1629
1630         ccw_device_set_offline(cgdev->cdev[1]);
1631         ccw_device_set_offline(cgdev->cdev[0]);
1632
1633         if (priv->channel[READ])
1634                 channel_remove(priv->channel[READ]);
1635         if (priv->channel[WRITE])
1636                 channel_remove(priv->channel[WRITE]);
1637         priv->channel[READ] = priv->channel[WRITE] = NULL;
1638
1639         return 0;
1640
1641 }
1642
1643
1644 static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1645 {
1646         struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1647
1648         BUG_ON(priv == NULL);
1649
1650         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1651                         "removing device %s, r/w = %s/%s, proto : %d",
1652                         priv->channel[READ]->netdev->name,
1653                         priv->channel[READ]->id, priv->channel[WRITE]->id,
1654                         priv->protocol);
1655
1656         if (cgdev->state == CCWGROUP_ONLINE)
1657                 ctcm_shutdown_device(cgdev);
1658         ctcm_remove_files(&cgdev->dev);
1659         dev_set_drvdata(&cgdev->dev, NULL);
1660         kfree(priv);
1661         put_device(&cgdev->dev);
1662 }
1663
1664 static struct ccwgroup_driver ctcm_group_driver = {
1665         .owner       = THIS_MODULE,
1666         .name        = CTC_DRIVER_NAME,
1667         .max_slaves  = 2,
1668         .driver_id   = 0xC3E3C3D4,      /* CTCM */
1669         .probe       = ctcm_probe_device,
1670         .remove      = ctcm_remove_device,
1671         .set_online  = ctcm_new_device,
1672         .set_offline = ctcm_shutdown_device,
1673 };
1674
1675
1676 /*
1677  * Module related routines
1678  */
1679
1680 /*
1681  * Prepare to be unloaded. Free IRQ's and release all resources.
1682  * This is called just before this module is unloaded. It is
1683  * not called, if the usage count is !0, so we don't need to check
1684  * for that.
1685  */
1686 static void __exit ctcm_exit(void)
1687 {
1688         unregister_cu3088_discipline(&ctcm_group_driver);
1689         ctcm_unregister_dbf_views();
1690         ctcm_pr_info("CTCM driver unloaded\n");
1691 }
1692
1693 /*
1694  * Print Banner.
1695  */
1696 static void print_banner(void)
1697 {
1698         printk(KERN_INFO "CTCM driver initialized\n");
1699 }
1700
1701 /**
1702  * Initialize module.
1703  * This is called just after the module is loaded.
1704  *
1705  * returns 0 on success, !0 on error.
1706  */
1707 static int __init ctcm_init(void)
1708 {
1709         int ret;
1710
1711         channels = NULL;
1712
1713         ret = ctcm_register_dbf_views();
1714         if (ret) {
1715                 return ret;
1716         }
1717         ret = register_cu3088_discipline(&ctcm_group_driver);
1718         if (ret) {
1719                 ctcm_unregister_dbf_views();
1720                 ctcm_pr_crit("ctcm_init failed with register_cu3088_discipline "
1721                                 "(rc = %d)\n", ret);
1722                 return ret;
1723         }
1724         print_banner();
1725         return ret;
1726 }
1727
1728 module_init(ctcm_init);
1729 module_exit(ctcm_exit);
1730
1731 MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1732 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1733 MODULE_LICENSE("GPL");
1734