drivers/s390/net/ctcm_main.c

   1 /*
   2  * drivers/s390/net/ctcm_main.c
   3  *
   4  * Copyright IBM Corp. 2001, 2009
   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 #define KMSG_COMPONENT "ctcm"
  25 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  26
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/kernel.h>
  30 #include <linux/slab.h>
  31 #include <linux/errno.h>
  32 #include <linux/types.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/timer.h>
  35 #include <linux/bitops.h>
  36
  37 #include <linux/signal.h>
  38 #include <linux/string.h>
  39
  40 #include <linux/ip.h>
  41 #include <linux/if_arp.h>
  42 #include <linux/tcp.h>
  43 #include <linux/skbuff.h>
  44 #include <linux/ctype.h>
  45 #include <net/dst.h>
  46
  47 #include <linux/io.h>
  48 #include <asm/ccwdev.h>
  49 #include <asm/ccwgroup.h>
  50 #include <linux/uaccess.h>
  51
  52 #include <asm/idals.h>
  53
  54 #include "cu3088.h"
  55 #include "ctcm_fsms.h"
  56 #include "ctcm_main.h"
  57
  58 /* Some common global variables */
  59
  60 /*
  61  * Linked list of all detected channels.
  62  */
  63 struct channel *channels;
  64
  65 /**
  66  * Unpack a just received skb and hand it over to
  67  * upper layers.
  68  *
  69  *  ch          The channel where this skb has been received.
  70  *  pskb        The received skb.
  71  */
  72 void ctcm_unpack_skb(struct channel *ch, struct sk_buff *pskb)
  73 {
  74         struct net_device *dev = ch->netdev;
  75         struct ctcm_priv *priv = dev->ml_priv;
  76         __u16 len = *((__u16 *) pskb->data);
  77
  78         skb_put(pskb, 2 + LL_HEADER_LENGTH);
  79         skb_pull(pskb, 2);
  80         pskb->dev = dev;
  81         pskb->ip_summed = CHECKSUM_UNNECESSARY;
  82         while (len > 0) {
  83                 struct sk_buff *skb;
  84                 int skblen;
  85                 struct ll_header *header = (struct ll_header *)pskb->data;
  86
  87                 skb_pull(pskb, LL_HEADER_LENGTH);
  88                 if ((ch->protocol == CTCM_PROTO_S390) &&
  89                     (header->type != ETH_P_IP)) {
  90                         if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
  91                                 ch->logflags |= LOG_FLAG_ILLEGALPKT;
  92                                 /*
  93                                  * Check packet type only if we stick strictly
  94                                  * to S/390's protocol of OS390. This only
  95                                  * supports IP. Otherwise allow any packet
  96                                  * type.
  97                                  */
  98                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
  99                                         "%s(%s): Illegal packet type 0x%04x"
 100                                         " - dropping",
 101                                         CTCM_FUNTAIL, dev->name, header->type);
 102                         }
 103                         priv->stats.rx_dropped++;
 104                         priv->stats.rx_frame_errors++;
 105                         return;
 106                 }
 107                 pskb->protocol = ntohs(header->type);
 108                 if ((header->length <= LL_HEADER_LENGTH) ||
 109                     (len <= LL_HEADER_LENGTH)) {
 110                         if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
 111                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 112                                         "%s(%s): Illegal packet size %d(%d,%d)"
 113                                         "- dropping",
 114                                         CTCM_FUNTAIL, dev->name,
 115                                         header->length, dev->mtu, len);
 116                                 ch->logflags |= LOG_FLAG_ILLEGALSIZE;
 117                         }
 118
 119                         priv->stats.rx_dropped++;
 120                         priv->stats.rx_length_errors++;
 121                         return;
 122                 }
 123                 header->length -= LL_HEADER_LENGTH;
 124                 len -= LL_HEADER_LENGTH;
 125                 if ((header->length > skb_tailroom(pskb)) ||
 126                         (header->length > len)) {
 127                         if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 128                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 129                                         "%s(%s): Packet size %d (overrun)"
 130                                         " - dropping", CTCM_FUNTAIL,
 131                                                 dev->name, header->length);
 132                                 ch->logflags |= LOG_FLAG_OVERRUN;
 133                         }
 134
 135                         priv->stats.rx_dropped++;
 136                         priv->stats.rx_length_errors++;
 137                         return;
 138                 }
 139                 skb_put(pskb, header->length);
 140                 skb_reset_mac_header(pskb);
 141                 len -= header->length;
 142                 skb = dev_alloc_skb(pskb->len);
 143                 if (!skb) {
 144                         if (!(ch->logflags & LOG_FLAG_NOMEM)) {
 145                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 146                                         "%s(%s): MEMORY allocation error",
 147                                                 CTCM_FUNTAIL, dev->name);
 148                                 ch->logflags |= LOG_FLAG_NOMEM;
 149                         }
 150                         priv->stats.rx_dropped++;
 151                         return;
 152                 }
 153                 skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
 154                                           pskb->len);
 155                 skb_reset_mac_header(skb);
 156                 skb->dev = pskb->dev;
 157                 skb->protocol = pskb->protocol;
 158                 pskb->ip_summed = CHECKSUM_UNNECESSARY;
 159                 skblen = skb->len;
 160                 /*
 161                  * reset logflags
 162                  */
 163                 ch->logflags = 0;
 164                 priv->stats.rx_packets++;
 165                 priv->stats.rx_bytes += skblen;
 166                 netif_rx_ni(skb);
 167                 dev->last_rx = jiffies;
 168                 if (len > 0) {
 169                         skb_pull(pskb, header->length);
 170                         if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
 171                                 CTCM_DBF_DEV_NAME(TRACE, dev,
 172                                         "Overrun in ctcm_unpack_skb");
 173                                 ch->logflags |= LOG_FLAG_OVERRUN;
 174                                 return;
 175                         }
 176                         skb_put(pskb, LL_HEADER_LENGTH);
 177                 }
 178         }
 179 }
 180
 181 /**
 182  * Release a specific channel in the channel list.
 183  *
 184  *  ch          Pointer to channel struct to be released.
 185  */
 186 static void channel_free(struct channel *ch)
 187 {
 188         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s)", CTCM_FUNTAIL, ch->id);
 189         ch->flags &= ~CHANNEL_FLAGS_INUSE;
 190         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
 191 }
 192
 193 /**
 194  * Remove a specific channel in the channel list.
 195  *
 196  *  ch          Pointer to channel struct to be released.
 197  */
 198 static void channel_remove(struct channel *ch)
 199 {
 200         struct channel **c = &channels;
 201         char chid[CTCM_ID_SIZE+1];
 202         int ok = 0;
 203
 204         if (ch == NULL)
 205                 return;
 206         else
 207                 strncpy(chid, ch->id, CTCM_ID_SIZE);
 208
 209         channel_free(ch);
 210         while (*c) {
 211                 if (*c == ch) {
 212                         *c = ch->next;
 213                         fsm_deltimer(&ch->timer);
 214                         if (IS_MPC(ch))
 215                                 fsm_deltimer(&ch->sweep_timer);
 216
 217                         kfree_fsm(ch->fsm);
 218                         clear_normalized_cda(&ch->ccw[4]);
 219                         if (ch->trans_skb != NULL) {
 220                                 clear_normalized_cda(&ch->ccw[1]);
 221                                 dev_kfree_skb_any(ch->trans_skb);
 222                         }
 223                         if (IS_MPC(ch)) {
 224                                 tasklet_kill(&ch->ch_tasklet);
 225                                 tasklet_kill(&ch->ch_disc_tasklet);
 226                                 kfree(ch->discontact_th);
 227                         }
 228                         kfree(ch->ccw);
 229                         kfree(ch->irb);
 230                         kfree(ch);
 231                         ok = 1;
 232                         break;
 233                 }
 234                 c = &((*c)->next);
 235         }
 236
 237         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
 238                         chid, ok ? "OK" : "failed");
 239 }
 240
 241 /**
 242  * Get a specific channel from the channel list.
 243  *
 244  *  type        Type of channel we are interested in.
 245  *  id          Id of channel we are interested in.
 246  *  direction   Direction we want to use this channel for.
 247  *
 248  * returns Pointer to a channel or NULL if no matching channel available.
 249  */
 250 static struct channel *channel_get(enum channel_types type,
 251                                         char *id, int direction)
 252 {
 253         struct channel *ch = channels;
 254
 255         while (ch && (strncmp(ch->id, id, CTCM_ID_SIZE) || (ch->type != type)))
 256                 ch = ch->next;
 257         if (!ch) {
 258                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 259                                 "%s(%d, %s, %d) not found in channel list\n",
 260                                 CTCM_FUNTAIL, type, id, direction);
 261         } else {
 262                 if (ch->flags & CHANNEL_FLAGS_INUSE)
 263                         ch = NULL;
 264                 else {
 265                         ch->flags |= CHANNEL_FLAGS_INUSE;
 266                         ch->flags &= ~CHANNEL_FLAGS_RWMASK;
 267                         ch->flags |= (direction == WRITE)
 268                             ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
 269                         fsm_newstate(ch->fsm, CTC_STATE_STOPPED);
 270                 }
 271         }
 272         return ch;
 273 }
 274
 275 static long ctcm_check_irb_error(struct ccw_device *cdev, struct irb *irb)
 276 {
 277         if (!IS_ERR(irb))
 278                 return 0;
 279
 280         CTCM_DBF_TEXT_(ERROR, CTC_DBF_WARN,
 281                         "irb error %ld on device %s\n",
 282                                 PTR_ERR(irb), dev_name(&cdev->dev));
 283
 284         switch (PTR_ERR(irb)) {
 285         case -EIO:
 286                 dev_err(&cdev->dev,
 287                         "An I/O-error occurred on the CTCM device\n");
 288                 break;
 289         case -ETIMEDOUT:
 290                 dev_err(&cdev->dev,
 291                         "An adapter hardware operation timed out\n");
 292                 break;
 293         default:
 294                 dev_err(&cdev->dev,
 295                         "An error occurred on the adapter hardware\n");
 296         }
 297         return PTR_ERR(irb);
 298 }
 299
 300
 301 /**
 302  * Check sense of a unit check.
 303  *
 304  *  ch          The channel, the sense code belongs to.
 305  *  sense       The sense code to inspect.
 306  */
 307 static inline void ccw_unit_check(struct channel *ch, __u8 sense)
 308 {
 309         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
 310                         "%s(%s): %02x",
 311                                 CTCM_FUNTAIL, ch->id, sense);
 312
 313         if (sense & SNS0_INTERVENTION_REQ) {
 314                 if (sense & 0x01) {
 315                         if (ch->sense_rc != 0x01) {
 316                                 pr_notice(
 317                                         "%s: The communication peer has "
 318                                         "disconnected\n", ch->id);
 319                                 ch->sense_rc = 0x01;
 320                         }
 321                         fsm_event(ch->fsm, CTC_EVENT_UC_RCRESET, ch);
 322                 } else {
 323                         if (ch->sense_rc != SNS0_INTERVENTION_REQ) {
 324                                 pr_notice(
 325                                         "%s: The remote operating system is "
 326                                         "not available\n", ch->id);
 327                                 ch->sense_rc = SNS0_INTERVENTION_REQ;
 328                         }
 329                         fsm_event(ch->fsm, CTC_EVENT_UC_RSRESET, ch);
 330                 }
 331         } else if (sense & SNS0_EQUIPMENT_CHECK) {
 332                 if (sense & SNS0_BUS_OUT_CHECK) {
 333                         if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 334                                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 335                                         "%s(%s): remote HW error %02x",
 336                                                 CTCM_FUNTAIL, ch->id, sense);
 337                                 ch->sense_rc = SNS0_BUS_OUT_CHECK;
 338                         }
 339                         fsm_event(ch->fsm, CTC_EVENT_UC_HWFAIL, ch);
 340                 } else {
 341                         if (ch->sense_rc != SNS0_EQUIPMENT_CHECK) {
 342                                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 343                                         "%s(%s): remote read parity error %02x",
 344                                                 CTCM_FUNTAIL, ch->id, sense);
 345                                 ch->sense_rc = SNS0_EQUIPMENT_CHECK;
 346                         }
 347                         fsm_event(ch->fsm, CTC_EVENT_UC_RXPARITY, ch);
 348                 }
 349         } else if (sense & SNS0_BUS_OUT_CHECK) {
 350                 if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 351                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 352                                 "%s(%s): BUS OUT error %02x",
 353                                         CTCM_FUNTAIL, ch->id, sense);
 354                         ch->sense_rc = SNS0_BUS_OUT_CHECK;
 355                 }
 356                 if (sense & 0x04)       /* data-streaming timeout */
 357                         fsm_event(ch->fsm, CTC_EVENT_UC_TXTIMEOUT, ch);
 358                 else                    /* Data-transfer parity error */
 359                         fsm_event(ch->fsm, CTC_EVENT_UC_TXPARITY, ch);
 360         } else if (sense & SNS0_CMD_REJECT) {
 361                 if (ch->sense_rc != SNS0_CMD_REJECT) {
 362                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 363                                 "%s(%s): Command rejected",
 364                                                 CTCM_FUNTAIL, ch->id);
 365                         ch->sense_rc = SNS0_CMD_REJECT;
 366                 }
 367         } else if (sense == 0) {
 368                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 369                         "%s(%s): Unit check ZERO",
 370                                         CTCM_FUNTAIL, ch->id);
 371                 fsm_event(ch->fsm, CTC_EVENT_UC_ZERO, ch);
 372         } else {
 373                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 374                         "%s(%s): Unit check code %02x unknown",
 375                                         CTCM_FUNTAIL, ch->id, sense);
 376                 fsm_event(ch->fsm, CTC_EVENT_UC_UNKNOWN, ch);
 377         }
 378 }
 379
 380 int ctcm_ch_alloc_buffer(struct channel *ch)
 381 {
 382         clear_normalized_cda(&ch->ccw[1]);
 383         ch->trans_skb = __dev_alloc_skb(ch->max_bufsize, GFP_ATOMIC | GFP_DMA);
 384         if (ch->trans_skb == NULL) {
 385                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 386                         "%s(%s): %s trans_skb allocation error",
 387                         CTCM_FUNTAIL, ch->id,
 388                         (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
 389                 return -ENOMEM;
 390         }
 391
 392         ch->ccw[1].count = ch->max_bufsize;
 393         if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
 394                 dev_kfree_skb(ch->trans_skb);
 395                 ch->trans_skb = NULL;
 396                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 397                         "%s(%s): %s set norm_cda failed",
 398                         CTCM_FUNTAIL, ch->id,
 399                         (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
 400                 return -ENOMEM;
 401         }
 402
 403         ch->ccw[1].count = 0;
 404         ch->trans_skb_data = ch->trans_skb->data;
 405         ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
 406         return 0;
 407 }
 408
 409 /*
 410  * Interface API for upper network layers
 411  */
 412
 413 /**
 414  * Open an interface.
 415  * Called from generic network layer when ifconfig up is run.
 416  *
 417  *  dev         Pointer to interface struct.
 418  *
 419  * returns 0 on success, -ERRNO on failure. (Never fails.)
 420  */
 421 int ctcm_open(struct net_device *dev)
 422 {
 423         struct ctcm_priv *priv = dev->ml_priv;
 424
 425         CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 426         if (!IS_MPC(priv))
 427                 fsm_event(priv->fsm,    DEV_EVENT_START, dev);
 428         return 0;
 429 }
 430
 431 /**
 432  * Close an interface.
 433  * Called from generic network layer when ifconfig down is run.
 434  *
 435  *  dev         Pointer to interface struct.
 436  *
 437  * returns 0 on success, -ERRNO on failure. (Never fails.)
 438  */
 439 int ctcm_close(struct net_device *dev)
 440 {
 441         struct ctcm_priv *priv = dev->ml_priv;
 442
 443         CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 444         if (!IS_MPC(priv))
 445                 fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
 446         return 0;
 447 }
 448
 449
 450 /**
 451  * Transmit a packet.
 452  * This is a helper function for ctcm_tx().
 453  *
 454  *  ch          Channel to be used for sending.
 455  *  skb         Pointer to struct sk_buff of packet to send.
 456  *            The linklevel header has already been set up
 457  *            by ctcm_tx().
 458  *
 459  * returns 0 on success, -ERRNO on failure. (Never fails.)
 460  */
 461 static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
 462 {
 463         unsigned long saveflags;
 464         struct ll_header header;
 465         int rc = 0;
 466         __u16 block_len;
 467         int ccw_idx;
 468         struct sk_buff *nskb;
 469         unsigned long hi;
 470
 471         /* we need to acquire the lock for testing the state
 472          * otherwise we can have an IRQ changing the state to
 473          * TXIDLE after the test but before acquiring the lock.
 474          */
 475         spin_lock_irqsave(&ch->collect_lock, saveflags);
 476         if (fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) {
 477                 int l = skb->len + LL_HEADER_LENGTH;
 478
 479                 if (ch->collect_len + l > ch->max_bufsize - 2) {
 480                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 481                         return -EBUSY;
 482                 } else {
 483                         atomic_inc(&skb->users);
 484                         header.length = l;
 485                         header.type = skb->protocol;
 486                         header.unused = 0;
 487                         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
 488                                LL_HEADER_LENGTH);
 489                         skb_queue_tail(&ch->collect_queue, skb);
 490                         ch->collect_len += l;
 491                 }
 492                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 493                                 goto done;
 494         }
 495         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 496         /*
 497          * Protect skb against beeing free'd by upper
 498          * layers.
 499          */
 500         atomic_inc(&skb->users);
 501         ch->prof.txlen += skb->len;
 502         header.length = skb->len + LL_HEADER_LENGTH;
 503         header.type = skb->protocol;
 504         header.unused = 0;
 505         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header, LL_HEADER_LENGTH);
 506         block_len = skb->len + 2;
 507         *((__u16 *)skb_push(skb, 2)) = block_len;
 508
 509         /*
 510          * IDAL support in CTCM is broken, so we have to
 511          * care about skb's above 2G ourselves.
 512          */
 513         hi = ((unsigned long)skb_tail_pointer(skb) + LL_HEADER_LENGTH) >> 31;
 514         if (hi) {
 515                 nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 516                 if (!nskb) {
 517                         atomic_dec(&skb->users);
 518                         skb_pull(skb, LL_HEADER_LENGTH + 2);
 519                         ctcm_clear_busy(ch->netdev);
 520                         return -ENOMEM;
 521                 } else {
 522                         memcpy(skb_put(nskb, skb->len), skb->data, skb->len);
 523                         atomic_inc(&nskb->users);
 524                         atomic_dec(&skb->users);
 525                         dev_kfree_skb_irq(skb);
 526                         skb = nskb;
 527                 }
 528         }
 529
 530         ch->ccw[4].count = block_len;
 531         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 532                 /*
 533                  * idal allocation failed, try via copying to
 534                  * trans_skb. trans_skb usually has a pre-allocated
 535                  * idal.
 536                  */
 537                 if (ctcm_checkalloc_buffer(ch)) {
 538                         /*
 539                          * Remove our header. It gets added
 540                          * again on retransmit.
 541                          */
 542                         atomic_dec(&skb->users);
 543                         skb_pull(skb, LL_HEADER_LENGTH + 2);
 544                         ctcm_clear_busy(ch->netdev);
 545                         return -ENOMEM;
 546                 }
 547
 548                 skb_reset_tail_pointer(ch->trans_skb);
 549                 ch->trans_skb->len = 0;
 550                 ch->ccw[1].count = skb->len;
 551                 skb_copy_from_linear_data(skb,
 552                                 skb_put(ch->trans_skb, skb->len), skb->len);
 553                 atomic_dec(&skb->users);
 554                 dev_kfree_skb_irq(skb);
 555                 ccw_idx = 0;
 556         } else {
 557                 skb_queue_tail(&ch->io_queue, skb);
 558                 ccw_idx = 3;
 559         }
 560         ch->retry = 0;
 561         fsm_newstate(ch->fsm, CTC_STATE_TX);
 562         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 563         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 564         ch->prof.send_stamp = current_kernel_time(); /* xtime */
 565         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx],
 566                                         (unsigned long)ch, 0xff, 0);
 567         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 568         if (ccw_idx == 3)
 569                 ch->prof.doios_single++;
 570         if (rc != 0) {
 571                 fsm_deltimer(&ch->timer);
 572                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
 573                 if (ccw_idx == 3)
 574                         skb_dequeue_tail(&ch->io_queue);
 575                 /*
 576                  * Remove our header. It gets added
 577                  * again on retransmit.
 578                  */
 579                 skb_pull(skb, LL_HEADER_LENGTH + 2);
 580         } else if (ccw_idx == 0) {
 581                 struct net_device *dev = ch->netdev;
 582                 struct ctcm_priv *priv = dev->ml_priv;
 583                 priv->stats.tx_packets++;
 584                 priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 585         }
 586 done:
 587         ctcm_clear_busy(ch->netdev);
 588         return rc;
 589 }
 590
 591 static void ctcmpc_send_sweep_req(struct channel *rch)
 592 {
 593         struct net_device *dev = rch->netdev;
 594         struct ctcm_priv *priv;
 595         struct mpc_group *grp;
 596         struct th_sweep *header;
 597         struct sk_buff *sweep_skb;
 598         struct channel *ch;
 599         /* int rc = 0; */
 600
 601         priv = dev->ml_priv;
 602         grp = priv->mpcg;
 603         ch = priv->channel[WRITE];
 604
 605         /* sweep processing is not complete until response and request */
 606         /* has completed for all read channels in group                */
 607         if (grp->in_sweep == 0) {
 608                 grp->in_sweep = 1;
 609                 grp->sweep_rsp_pend_num = grp->active_channels[READ];
 610                 grp->sweep_req_pend_num = grp->active_channels[READ];
 611         }
 612
 613         sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
 614
 615         if (sweep_skb == NULL)  {
 616                 /* rc = -ENOMEM; */
 617                                 goto nomem;
 618         }
 619
 620         header = kmalloc(TH_SWEEP_LENGTH, gfp_type());
 621
 622         if (!header) {
 623                 dev_kfree_skb_any(sweep_skb);
 624                 /* rc = -ENOMEM; */
 625                                 goto nomem;
 626         }
 627
 628         header->th.th_seg       = 0x00 ;
 629         header->th.th_ch_flag   = TH_SWEEP_REQ;  /* 0x0f */
 630         header->th.th_blk_flag  = 0x00;
 631         header->th.th_is_xid    = 0x00;
 632         header->th.th_seq_num   = 0x00;
 633         header->sw.th_last_seq  = ch->th_seq_num;
 634
 635         memcpy(skb_put(sweep_skb, TH_SWEEP_LENGTH), header, TH_SWEEP_LENGTH);
 636
 637         kfree(header);
 638
 639         dev->trans_start = jiffies;
 640         skb_queue_tail(&ch->sweep_queue, sweep_skb);
 641
 642         fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
 643
 644         return;
 645
 646 nomem:
 647         grp->in_sweep = 0;
 648         ctcm_clear_busy(dev);
 649         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 650
 651         return;
 652 }
 653
 654 /*
 655  * MPC mode version of transmit_skb
 656  */
 657 static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
 658 {
 659         struct pdu *p_header;
 660         struct net_device *dev = ch->netdev;
 661         struct ctcm_priv *priv = dev->ml_priv;
 662         struct mpc_group *grp = priv->mpcg;
 663         struct th_header *header;
 664         struct sk_buff *nskb;
 665         int rc = 0;
 666         int ccw_idx;
 667         unsigned long hi;
 668         unsigned long saveflags = 0;    /* avoids compiler warning */
 669         __u16 block_len;
 670
 671         CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
 672                         __func__, dev->name, smp_processor_id(), ch,
 673                                         ch->id, fsm_getstate_str(ch->fsm));
 674
 675         if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
 676                 spin_lock_irqsave(&ch->collect_lock, saveflags);
 677                 atomic_inc(&skb->users);
 678                 p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
 679
 680                 if (!p_header) {
 681                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 682                                 goto nomem_exit;
 683                 }
 684
 685                 p_header->pdu_offset = skb->len;
 686                 p_header->pdu_proto = 0x01;
 687                 p_header->pdu_flag = 0x00;
 688                 if (skb->protocol == ntohs(ETH_P_SNAP)) {
 689                         p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
 690                 } else {
 691                         p_header->pdu_flag |= PDU_FIRST;
 692                 }
 693                 p_header->pdu_seq = 0;
 694                 memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header,
 695                        PDU_HEADER_LENGTH);
 696
 697                 CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
 698                                 "pdu header and data for up to 32 bytes:\n",
 699                                 __func__, dev->name, skb->len);
 700                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 701
 702                 skb_queue_tail(&ch->collect_queue, skb);
 703                 ch->collect_len += skb->len;
 704                 kfree(p_header);
 705
 706                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 707                         goto done;
 708         }
 709
 710         /*
 711          * Protect skb against beeing free'd by upper
 712          * layers.
 713          */
 714         atomic_inc(&skb->users);
 715
 716         block_len = skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 717         /*
 718          * IDAL support in CTCM is broken, so we have to
 719          * care about skb's above 2G ourselves.
 720          */
 721         hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
 722         if (hi) {
 723                 nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 724                 if (!nskb) {
 725                         goto nomem_exit;
 726                 } else {
 727                         memcpy(skb_put(nskb, skb->len), skb->data, skb->len);
 728                         atomic_inc(&nskb->users);
 729                         atomic_dec(&skb->users);
 730                         dev_kfree_skb_irq(skb);
 731                         skb = nskb;
 732                 }
 733         }
 734
 735         p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
 736
 737         if (!p_header)
 738                 goto nomem_exit;
 739
 740         p_header->pdu_offset = skb->len;
 741         p_header->pdu_proto = 0x01;
 742         p_header->pdu_flag = 0x00;
 743         p_header->pdu_seq = 0;
 744         if (skb->protocol == ntohs(ETH_P_SNAP)) {
 745                 p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
 746         } else {
 747                 p_header->pdu_flag |= PDU_FIRST;
 748         }
 749         memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header, PDU_HEADER_LENGTH);
 750
 751         kfree(p_header);
 752
 753         if (ch->collect_len > 0) {
 754                 spin_lock_irqsave(&ch->collect_lock, saveflags);
 755                 skb_queue_tail(&ch->collect_queue, skb);
 756                 ch->collect_len += skb->len;
 757                 skb = skb_dequeue(&ch->collect_queue);
 758                 ch->collect_len -= skb->len;
 759                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 760         }
 761
 762         p_header = (struct pdu *)skb->data;
 763         p_header->pdu_flag |= PDU_LAST;
 764
 765         ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
 766
 767         header = kmalloc(TH_HEADER_LENGTH, gfp_type());
 768         if (!header)
 769                 goto nomem_exit;
 770
 771         header->th_seg = 0x00;
 772         header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
 773         header->th_blk_flag = 0x00;
 774         header->th_is_xid = 0x00;          /* Just data here */
 775         ch->th_seq_num++;
 776         header->th_seq_num = ch->th_seq_num;
 777
 778         CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
 779                        __func__, dev->name, ch->th_seq_num);
 780
 781         /* put the TH on the packet */
 782         memcpy(skb_push(skb, TH_HEADER_LENGTH), header, TH_HEADER_LENGTH);
 783
 784         kfree(header);
 785
 786         CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
 787                         "up to 32 bytes sent to vtam:\n",
 788                                 __func__, dev->name, skb->len);
 789         CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 790
 791         ch->ccw[4].count = skb->len;
 792         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 793                 /*
 794                  * idal allocation failed, try via copying to trans_skb.
 795                  * trans_skb usually has a pre-allocated idal.
 796                  */
 797                 if (ctcm_checkalloc_buffer(ch)) {
 798                         /*
 799                          * Remove our header.
 800                          * It gets added again on retransmit.
 801                          */
 802                                 goto nomem_exit;
 803                 }
 804
 805                 skb_reset_tail_pointer(ch->trans_skb);
 806                 ch->trans_skb->len = 0;
 807                 ch->ccw[1].count = skb->len;
 808                 memcpy(skb_put(ch->trans_skb, skb->len), skb->data, skb->len);
 809                 atomic_dec(&skb->users);
 810                 dev_kfree_skb_irq(skb);
 811                 ccw_idx = 0;
 812                 CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
 813                                 "up to 32 bytes sent to vtam:\n",
 814                                 __func__, dev->name, ch->trans_skb->len);
 815                 CTCM_D3_DUMP((char *)ch->trans_skb->data,
 816                                 min_t(int, 32, ch->trans_skb->len));
 817         } else {
 818                 skb_queue_tail(&ch->io_queue, skb);
 819                 ccw_idx = 3;
 820         }
 821         ch->retry = 0;
 822         fsm_newstate(ch->fsm, CTC_STATE_TX);
 823         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 824
 825         if (do_debug_ccw)
 826                 ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 827                                         sizeof(struct ccw1) * 3);
 828
 829         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 830         ch->prof.send_stamp = current_kernel_time(); /* xtime */
 831         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx],
 832                                         (unsigned long)ch, 0xff, 0);
 833         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 834         if (ccw_idx == 3)
 835                 ch->prof.doios_single++;
 836         if (rc != 0) {
 837                 fsm_deltimer(&ch->timer);
 838                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
 839                 if (ccw_idx == 3)
 840                         skb_dequeue_tail(&ch->io_queue);
 841         } else if (ccw_idx == 0) {
 842                 priv->stats.tx_packets++;
 843                 priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
 844         }
 845         if (ch->th_seq_num > 0xf0000000)        /* Chose at random. */
 846                 ctcmpc_send_sweep_req(ch);
 847
 848         goto done;
 849 nomem_exit:
 850         CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
 851                         "%s(%s): MEMORY allocation ERROR\n",
 852                         CTCM_FUNTAIL, ch->id);
 853         rc = -ENOMEM;
 854         atomic_dec(&skb->users);
 855         dev_kfree_skb_any(skb);
 856         fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
 857 done:
 858         CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
 859         return rc;
 860 }
 861
 862 /**
 863  * Start transmission of a packet.
 864  * Called from generic network device layer.
 865  *
 866  *  skb         Pointer to buffer containing the packet.
 867  *  dev         Pointer to interface struct.
 868  *
 869  * returns 0 if packet consumed, !0 if packet rejected.
 870  *         Note: If we return !0, then the packet is free'd by
 871  *               the generic network layer.
 872  */
 873 /* first merge version - leaving both functions separated */
 874 static int ctcm_tx(struct sk_buff *skb, struct net_device *dev)
 875 {
 876         struct ctcm_priv *priv = dev->ml_priv;
 877
 878         if (skb == NULL) {
 879                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 880                                 "%s(%s): NULL sk_buff passed",
 881                                         CTCM_FUNTAIL, dev->name);
 882                 priv->stats.tx_dropped++;
 883                 return 0;
 884         }
 885         if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
 886                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 887                         "%s(%s): Got sk_buff with head room < %ld bytes",
 888                         CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
 889                 dev_kfree_skb(skb);
 890                 priv->stats.tx_dropped++;
 891                 return 0;
 892         }
 893
 894         /*
 895          * If channels are not running, try to restart them
 896          * and throw away packet.
 897          */
 898         if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
 899                 fsm_event(priv->fsm, DEV_EVENT_START, dev);
 900                 dev_kfree_skb(skb);
 901                 priv->stats.tx_dropped++;
 902                 priv->stats.tx_errors++;
 903                 priv->stats.tx_carrier_errors++;
 904                 return 0;
 905         }
 906
 907         if (ctcm_test_and_set_busy(dev))
 908                 return NETDEV_TX_BUSY;
 909
 910         dev->trans_start = jiffies;
 911         if (ctcm_transmit_skb(priv->channel[WRITE], skb) != 0)
 912                 return NETDEV_TX_BUSY;
 913         return 0;
 914 }
 915
 916 /* unmerged MPC variant of ctcm_tx */
 917 static int ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
 918 {
 919         int len = 0;
 920         struct ctcm_priv *priv = dev->ml_priv;
 921         struct mpc_group *grp  = priv->mpcg;
 922         struct sk_buff *newskb = NULL;
 923
 924         /*
 925          * Some sanity checks ...
 926          */
 927         if (skb == NULL) {
 928                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 929                         "%s(%s): NULL sk_buff passed",
 930                                         CTCM_FUNTAIL, dev->name);
 931                 priv->stats.tx_dropped++;
 932                                         goto done;
 933         }
 934         if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
 935                 CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 936                         "%s(%s): Got sk_buff with head room < %ld bytes",
 937                         CTCM_FUNTAIL, dev->name,
 938                                 TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 939
 940                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 941
 942                 len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 943                 newskb = __dev_alloc_skb(len, gfp_type() | GFP_DMA);
 944
 945                 if (!newskb) {
 946                         CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 947                                 "%s: %s: __dev_alloc_skb failed",
 948                                                 __func__, dev->name);
 949
 950                         dev_kfree_skb_any(skb);
 951                         priv->stats.tx_dropped++;
 952                         priv->stats.tx_errors++;
 953                         priv->stats.tx_carrier_errors++;
 954                         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 955                                         goto done;
 956                 }
 957                 newskb->protocol = skb->protocol;
 958                 skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 959                 memcpy(skb_put(newskb, skb->len), skb->data, skb->len);
 960                 dev_kfree_skb_any(skb);
 961                 skb = newskb;
 962         }
 963
 964         /*
 965          * If channels are not running,
 966          * notify anybody about a link failure and throw
 967          * away packet.
 968          */
 969         if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
 970            (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
 971                 dev_kfree_skb_any(skb);
 972                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 973                         "%s(%s): inactive MPCGROUP - dropped",
 974                                         CTCM_FUNTAIL, dev->name);
 975                 priv->stats.tx_dropped++;
 976                 priv->stats.tx_errors++;
 977                 priv->stats.tx_carrier_errors++;
 978                                         goto done;
 979         }
 980
 981         if (ctcm_test_and_set_busy(dev)) {
 982                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 983                         "%s(%s): device busy - dropped",
 984                                         CTCM_FUNTAIL, dev->name);
 985                 dev_kfree_skb_any(skb);
 986                 priv->stats.tx_dropped++;
 987                 priv->stats.tx_errors++;
 988                 priv->stats.tx_carrier_errors++;
 989                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 990                                         goto done;
 991         }
 992
 993         dev->trans_start = jiffies;
 994         if (ctcmpc_transmit_skb(priv->channel[WRITE], skb) != 0) {
 995                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 996                         "%s(%s): device error - dropped",
 997                                         CTCM_FUNTAIL, dev->name);
 998                 dev_kfree_skb_any(skb);
 999                 priv->stats.tx_dropped++;
1000                 priv->stats.tx_errors++;
1001                 priv->stats.tx_carrier_errors++;
1002                 ctcm_clear_busy(dev);
1003                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1004                                         goto done;
1005         }
1006         ctcm_clear_busy(dev);
1007 done:
1008         if (do_debug)
1009                 MPC_DBF_DEV_NAME(TRACE, dev, "exit");
1010
1011         return 0;       /* handle freeing of skb here */
1012 }
1013
1014
1015 /**
1016  * Sets MTU of an interface.
1017  *
1018  *  dev         Pointer to interface struct.
1019  *  new_mtu     The new MTU to use for this interface.
1020  *
1021  * returns 0 on success, -EINVAL if MTU is out of valid range.
1022  *         (valid range is 576 .. 65527). If VM is on the
1023  *         remote side, maximum MTU is 32760, however this is
1024  *         not checked here.
1025  */
1026 static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
1027 {
1028         struct ctcm_priv *priv;
1029         int max_bufsize;
1030
1031         if (new_mtu < 576 || new_mtu > 65527)
1032                 return -EINVAL;
1033
1034         priv = dev->ml_priv;
1035         max_bufsize = priv->channel[READ]->max_bufsize;
1036
1037         if (IS_MPC(priv)) {
1038                 if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
1039                         return -EINVAL;
1040                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1041         } else {
1042                 if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
1043                         return -EINVAL;
1044                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1045         }
1046         dev->mtu = new_mtu;
1047         return 0;
1048 }
1049
1050 /**
1051  * Returns interface statistics of a device.
1052  *
1053  *  dev         Pointer to interface struct.
1054  *
1055  * returns Pointer to stats struct of this interface.
1056  */
1057 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1058 {
1059         return &((struct ctcm_priv *)dev->ml_priv)->stats;
1060 }
1061
1062 static void ctcm_free_netdevice(struct net_device *dev)
1063 {
1064         struct ctcm_priv *priv;
1065         struct mpc_group *grp;
1066
1067         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1068                         "%s(%s)", CTCM_FUNTAIL, dev->name);
1069         priv = dev->ml_priv;
1070         if (priv) {
1071                 grp = priv->mpcg;
1072                 if (grp) {
1073                         if (grp->fsm)
1074                                 kfree_fsm(grp->fsm);
1075                         if (grp->xid_skb)
1076                                 dev_kfree_skb(grp->xid_skb);
1077                         if (grp->rcvd_xid_skb)
1078                                 dev_kfree_skb(grp->rcvd_xid_skb);
1079                         tasklet_kill(&grp->mpc_tasklet2);
1080                         kfree(grp);
1081                         priv->mpcg = NULL;
1082                 }
1083                 if (priv->fsm) {
1084                         kfree_fsm(priv->fsm);
1085                         priv->fsm = NULL;
1086                 }
1087                 kfree(priv->xid);
1088                 priv->xid = NULL;
1089         /*
1090          * Note: kfree(priv); is done in "opposite" function of
1091          * allocator function probe_device which is remove_device.
1092          */
1093         }
1094 #ifdef MODULE
1095         free_netdev(dev);
1096 #endif
1097 }
1098
1099 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1100
1101 static const struct net_device_ops ctcm_netdev_ops = {
1102         .ndo_open               = ctcm_open,
1103         .ndo_stop               = ctcm_close,
1104         .ndo_get_stats          = ctcm_stats,
1105         .ndo_change_mtu         = ctcm_change_mtu,
1106         .ndo_start_xmit         = ctcm_tx,
1107 };
1108
1109 static const struct net_device_ops ctcm_mpc_netdev_ops = {
1110         .ndo_open               = ctcm_open,
1111         .ndo_stop               = ctcm_close,
1112         .ndo_get_stats          = ctcm_stats,
1113         .ndo_change_mtu         = ctcm_change_mtu,
1114         .ndo_start_xmit         = ctcmpc_tx,
1115 };
1116
1117 void static ctcm_dev_setup(struct net_device *dev)
1118 {
1119         dev->type = ARPHRD_SLIP;
1120         dev->tx_queue_len = 100;
1121         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1122 }
1123
1124 /*
1125  * Initialize everything of the net device except the name and the
1126  * channel structs.
1127  */
1128 static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1129 {
1130         struct net_device *dev;
1131         struct mpc_group *grp;
1132         if (!priv)
1133                 return NULL;
1134
1135         if (IS_MPC(priv))
1136                 dev = alloc_netdev(0, MPC_DEVICE_GENE, ctcm_dev_setup);
1137         else
1138                 dev = alloc_netdev(0, CTC_DEVICE_GENE, ctcm_dev_setup);
1139
1140         if (!dev) {
1141                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1142                         "%s: MEMORY allocation ERROR",
1143                         CTCM_FUNTAIL);
1144                 return NULL;
1145         }
1146         dev->ml_priv = priv;
1147         priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1148                                 CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1149                                 dev_fsm, dev_fsm_len, GFP_KERNEL);
1150         if (priv->fsm == NULL) {
1151                 CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1152                 kfree(dev);
1153                 return NULL;
1154         }
1155         fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1156         fsm_settimer(priv->fsm, &priv->restart_timer);
1157
1158         if (IS_MPC(priv)) {
1159                 /*  MPC Group Initializations  */
1160                 grp = ctcmpc_init_mpc_group(priv);
1161                 if (grp == NULL) {
1162                         MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1163                         kfree(dev);
1164                         return NULL;
1165                 }
1166                 tasklet_init(&grp->mpc_tasklet2,
1167                                 mpc_group_ready, (unsigned long)dev);
1168                 dev->mtu = MPC_BUFSIZE_DEFAULT -
1169                                 TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1170
1171                 dev->netdev_ops = &ctcm_mpc_netdev_ops;
1172                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1173                 priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1174         } else {
1175                 dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1176                 dev->netdev_ops = &ctcm_netdev_ops;
1177                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1178         }
1179
1180         CTCMY_DBF_DEV(SETUP, dev, "finished");
1181
1182         return dev;
1183 }
1184
1185 /**
1186  * Main IRQ handler.
1187  *
1188  *  cdev        The ccw_device the interrupt is for.
1189  *  intparm     interruption parameter.
1190  *  irb         interruption response block.
1191  */
1192 static void ctcm_irq_handler(struct ccw_device *cdev,
1193                                 unsigned long intparm, struct irb *irb)
1194 {
1195         struct channel          *ch;
1196         struct net_device       *dev;
1197         struct ctcm_priv        *priv;
1198         struct ccwgroup_device  *cgdev;
1199         int cstat;
1200         int dstat;
1201
1202         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1203                 "Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1204
1205         if (ctcm_check_irb_error(cdev, irb))
1206                 return;
1207
1208         cgdev = dev_get_drvdata(&cdev->dev);
1209
1210         cstat = irb->scsw.cmd.cstat;
1211         dstat = irb->scsw.cmd.dstat;
1212
1213         /* Check for unsolicited interrupts. */
1214         if (cgdev == NULL) {
1215                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1216                         "%s(%s) unsolicited irq: c-%02x d-%02x\n",
1217                         CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1218                 dev_warn(&cdev->dev,
1219                         "The adapter received a non-specific IRQ\n");
1220                 return;
1221         }
1222
1223         priv = dev_get_drvdata(&cgdev->dev);
1224
1225         /* Try to extract channel from driver data. */
1226         if (priv->channel[READ]->cdev == cdev)
1227                 ch = priv->channel[READ];
1228         else if (priv->channel[WRITE]->cdev == cdev)
1229                 ch = priv->channel[WRITE];
1230         else {
1231                 dev_err(&cdev->dev,
1232                         "%s: Internal error: Can't determine channel for "
1233                         "interrupt device %s\n",
1234                         __func__, dev_name(&cdev->dev));
1235                         /* Explain: inconsistent internal structures */
1236                 return;
1237         }
1238
1239         dev = ch->netdev;
1240         if (dev == NULL) {
1241                 dev_err(&cdev->dev,
1242                         "%s Internal error: net_device is NULL, ch = 0x%p\n",
1243                         __func__, ch);
1244                         /* Explain: inconsistent internal structures */
1245                 return;
1246         }
1247
1248         /* Copy interruption response block. */
1249         memcpy(ch->irb, irb, sizeof(struct irb));
1250
1251         /* Issue error message and return on subchannel error code */
1252         if (irb->scsw.cmd.cstat) {
1253                 fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1254                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1255                         "%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1256                                 CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1257                 dev_warn(&cdev->dev,
1258                                 "A check occurred on the subchannel\n");
1259                 return;
1260         }
1261
1262         /* Check the reason-code of a unit check */
1263         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1264                 if ((irb->ecw[0] & ch->sense_rc) == 0)
1265                         /* print it only once */
1266                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1267                                 "%s(%s): sense=%02x, ds=%02x",
1268                                 CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1269                 ccw_unit_check(ch, irb->ecw[0]);
1270                 return;
1271         }
1272         if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1273                 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1274                         fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1275                 else
1276                         fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1277                 return;
1278         }
1279         if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1280                 fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1281                 return;
1282         }
1283         if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1284             (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1285             (irb->scsw.cmd.stctl ==
1286              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1287                 fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1288         else
1289                 fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1290
1291 }
1292
1293 /**
1294  * Add ctcm specific attributes.
1295  * Add ctcm private data.
1296  *
1297  *  cgdev       pointer to ccwgroup_device just added
1298  *
1299  * returns 0 on success, !0 on failure.
1300  */
1301 static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1302 {
1303         struct ctcm_priv *priv;
1304         int rc;
1305
1306         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1307                         "%s %p",
1308                         __func__, cgdev);
1309
1310         if (!get_device(&cgdev->dev))
1311                 return -ENODEV;
1312
1313         priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1314         if (!priv) {
1315                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1316                         "%s: memory allocation failure",
1317                         CTCM_FUNTAIL);
1318                 put_device(&cgdev->dev);
1319                 return -ENOMEM;
1320         }
1321
1322         rc = ctcm_add_files(&cgdev->dev);
1323         if (rc) {
1324                 kfree(priv);
1325                 put_device(&cgdev->dev);
1326                 return rc;
1327         }
1328         priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1329         cgdev->cdev[0]->handler = ctcm_irq_handler;
1330         cgdev->cdev[1]->handler = ctcm_irq_handler;
1331         dev_set_drvdata(&cgdev->dev, priv);
1332
1333         return 0;
1334 }
1335
1336 /**
1337  * Add a new channel to the list of channels.
1338  * Keeps the channel list sorted.
1339  *
1340  *  cdev        The ccw_device to be added.
1341  *  type        The type class of the new channel.
1342  *  priv        Points to the private data of the ccwgroup_device.
1343  *
1344  * returns 0 on success, !0 on error.
1345  */
1346 static int add_channel(struct ccw_device *cdev, enum channel_types type,
1347                                 struct ctcm_priv *priv)
1348 {
1349         struct channel **c = &channels;
1350         struct channel *ch;
1351         int ccw_num;
1352         int rc = 0;
1353
1354         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1355                 "%s(%s), type %d, proto %d",
1356                         __func__, dev_name(&cdev->dev), type, priv->protocol);
1357
1358         ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1359         if (ch == NULL)
1360                 return -ENOMEM;
1361
1362         ch->protocol = priv->protocol;
1363         if (IS_MPC(priv)) {
1364                 ch->discontact_th = (struct th_header *)
1365                                 kzalloc(TH_HEADER_LENGTH, gfp_type());
1366                 if (ch->discontact_th == NULL)
1367                                         goto nomem_return;
1368
1369                 ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1370                 tasklet_init(&ch->ch_disc_tasklet,
1371                         mpc_action_send_discontact, (unsigned long)ch);
1372
1373                 tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1374                 ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1375                 ccw_num = 17;
1376         } else
1377                 ccw_num = 8;
1378
1379         ch->ccw = (struct ccw1 *)
1380                 kzalloc(ccw_num * sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1381         if (ch->ccw == NULL)
1382                                         goto nomem_return;
1383
1384         ch->cdev = cdev;
1385         snprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1386         ch->type = type;
1387
1388         /**
1389          * "static" ccws are used in the following way:
1390          *
1391          * ccw[0..2] (Channel program for generic I/O):
1392          *           0: prepare
1393          *           1: read or write (depending on direction) with fixed
1394          *              buffer (idal allocated once when buffer is allocated)
1395          *           2: nop
1396          * ccw[3..5] (Channel program for direct write of packets)
1397          *           3: prepare
1398          *           4: write (idal allocated on every write).
1399          *           5: nop
1400          * ccw[6..7] (Channel program for initial channel setup):
1401          *           6: set extended mode
1402          *           7: nop
1403          *
1404          * ch->ccw[0..5] are initialized in ch_action_start because
1405          * the channel's direction is yet unknown here.
1406          *
1407          * ccws used for xid2 negotiations
1408          *  ch-ccw[8-14] need to be used for the XID exchange either
1409          *    X side XID2 Processing
1410          *       8:  write control
1411          *       9:  write th
1412          *           10: write XID
1413          *           11: read th from secondary
1414          *           12: read XID   from secondary
1415          *           13: read 4 byte ID
1416          *           14: nop
1417          *    Y side XID Processing
1418          *           8:  sense
1419          *       9:  read th
1420          *           10: read XID
1421          *           11: write th
1422          *           12: write XID
1423          *           13: write 4 byte ID
1424          *           14: nop
1425          *
1426          *  ccws used for double noop due to VM timing issues
1427          *  which result in unrecoverable Busy on channel
1428          *       15: nop
1429          *       16: nop
1430          */
1431         ch->ccw[6].cmd_code     = CCW_CMD_SET_EXTENDED;
1432         ch->ccw[6].flags        = CCW_FLAG_SLI;
1433
1434         ch->ccw[7].cmd_code     = CCW_CMD_NOOP;
1435         ch->ccw[7].flags        = CCW_FLAG_SLI;
1436
1437         if (IS_MPC(priv)) {
1438                 ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1439                 ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1440                 ch->ccw[15].count    = TH_HEADER_LENGTH;
1441                 ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1442
1443                 ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1444                 ch->ccw[16].flags    = CCW_FLAG_SLI;
1445
1446                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1447                                 ctc_ch_event_names, CTC_MPC_NR_STATES,
1448                                 CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1449                                 mpc_ch_fsm_len, GFP_KERNEL);
1450         } else {
1451                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1452                                 ctc_ch_event_names, CTC_NR_STATES,
1453                                 CTC_NR_EVENTS, ch_fsm,
1454                                 ch_fsm_len, GFP_KERNEL);
1455         }
1456         if (ch->fsm == NULL)
1457                                 goto free_return;
1458
1459         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1460
1461         ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1462         if (ch->irb == NULL)
1463                                 goto nomem_return;
1464
1465         while (*c && ctcm_less_than((*c)->id, ch->id))
1466                 c = &(*c)->next;
1467
1468         if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1469                 CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1470                                 "%s (%s) already in list, using old entry",
1471                                 __func__, (*c)->id);
1472
1473                                 goto free_return;
1474         }
1475
1476         spin_lock_init(&ch->collect_lock);
1477
1478         fsm_settimer(ch->fsm, &ch->timer);
1479         skb_queue_head_init(&ch->io_queue);
1480         skb_queue_head_init(&ch->collect_queue);
1481
1482         if (IS_MPC(priv)) {
1483                 fsm_settimer(ch->fsm, &ch->sweep_timer);
1484                 skb_queue_head_init(&ch->sweep_queue);
1485         }
1486         ch->next = *c;
1487         *c = ch;
1488         return 0;
1489
1490 nomem_return:
1491         rc = -ENOMEM;
1492
1493 free_return:    /* note that all channel pointers are 0 or valid */
1494         kfree(ch->ccw);
1495         kfree(ch->discontact_th);
1496         kfree_fsm(ch->fsm);
1497         kfree(ch->irb);
1498         kfree(ch);
1499         return rc;
1500 }
1501
1502 /*
1503  * Return type of a detected device.
1504  */
1505 static enum channel_types get_channel_type(struct ccw_device_id *id)
1506 {
1507         enum channel_types type;
1508         type = (enum channel_types)id->driver_info;
1509
1510         if (type == channel_type_ficon)
1511                 type = channel_type_escon;
1512
1513         return type;
1514 }
1515
1516 /**
1517  *
1518  * Setup an interface.
1519  *
1520  *  cgdev       Device to be setup.
1521  *
1522  * returns 0 on success, !0 on failure.
1523  */
1524 static int ctcm_new_device(struct ccwgroup_device *cgdev)
1525 {
1526         char read_id[CTCM_ID_SIZE];
1527         char write_id[CTCM_ID_SIZE];
1528         int direction;
1529         enum channel_types type;
1530         struct ctcm_priv *priv;
1531         struct net_device *dev;
1532         struct ccw_device *cdev0;
1533         struct ccw_device *cdev1;
1534         int ret;
1535
1536         priv = dev_get_drvdata(&cgdev->dev);
1537         if (!priv)
1538                 return -ENODEV;
1539
1540         cdev0 = cgdev->cdev[0];
1541         cdev1 = cgdev->cdev[1];
1542
1543         type = get_channel_type(&cdev0->id);
1544
1545         snprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1546         snprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1547
1548         ret = add_channel(cdev0, type, priv);
1549         if (ret)
1550                 return ret;
1551         ret = add_channel(cdev1, type, priv);
1552         if (ret)
1553                 return ret;
1554
1555         ret = ccw_device_set_online(cdev0);
1556         if (ret != 0) {
1557                 /* may be ok to fail now - can be done later */
1558                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1559                         "%s(%s) set_online rc=%d",
1560                                 CTCM_FUNTAIL, read_id, ret);
1561         }
1562
1563         ret = ccw_device_set_online(cdev1);
1564         if (ret != 0) {
1565                 /* may be ok to fail now - can be done later */
1566                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1567                         "%s(%s) set_online rc=%d",
1568                                 CTCM_FUNTAIL, write_id, ret);
1569         }
1570
1571         dev = ctcm_init_netdevice(priv);
1572         if (dev == NULL)
1573                         goto out;
1574
1575         for (direction = READ; direction <= WRITE; direction++) {
1576                 priv->channel[direction] =
1577                     channel_get(type, direction == READ ? read_id : write_id,
1578                                 direction);
1579                 if (priv->channel[direction] == NULL) {
1580                         if (direction == WRITE)
1581                                 channel_free(priv->channel[READ]);
1582                         goto out_dev;
1583                 }
1584                 priv->channel[direction]->netdev = dev;
1585                 priv->channel[direction]->protocol = priv->protocol;
1586                 priv->channel[direction]->max_bufsize = priv->buffer_size;
1587         }
1588         /* sysfs magic */
1589         SET_NETDEV_DEV(dev, &cgdev->dev);
1590
1591         if (register_netdev(dev))
1592                         goto out_dev;
1593
1594         if (ctcm_add_attributes(&cgdev->dev)) {
1595                 unregister_netdev(dev);
1596                         goto out_dev;
1597         }
1598
1599         strlcpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1600
1601         dev_info(&dev->dev,
1602                 "setup OK : r/w = %s/%s, protocol : %d\n",
1603                         priv->channel[READ]->id,
1604                         priv->channel[WRITE]->id, priv->protocol);
1605
1606         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1607                 "setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1608                         priv->channel[READ]->id,
1609                         priv->channel[WRITE]->id, priv->protocol);
1610
1611         return 0;
1612 out_dev:
1613         ctcm_free_netdevice(dev);
1614 out:
1615         ccw_device_set_offline(cgdev->cdev[1]);
1616         ccw_device_set_offline(cgdev->cdev[0]);
1617
1618         return -ENODEV;
1619 }
1620
1621 /**
1622  * Shutdown an interface.
1623  *
1624  *  cgdev       Device to be shut down.
1625  *
1626  * returns 0 on success, !0 on failure.
1627  */
1628 static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1629 {
1630         struct ctcm_priv *priv;
1631         struct net_device *dev;
1632
1633         priv = dev_get_drvdata(&cgdev->dev);
1634         if (!priv)
1635                 return -ENODEV;
1636
1637         if (priv->channel[READ]) {
1638                 dev = priv->channel[READ]->netdev;
1639                 CTCM_DBF_DEV(SETUP, dev, "");
1640                 /* Close the device */
1641                 ctcm_close(dev);
1642                 dev->flags &= ~IFF_RUNNING;
1643                 ctcm_remove_attributes(&cgdev->dev);
1644                 channel_free(priv->channel[READ]);
1645         } else
1646                 dev = NULL;
1647
1648         if (priv->channel[WRITE])
1649                 channel_free(priv->channel[WRITE]);
1650
1651         if (dev) {
1652                 unregister_netdev(dev);
1653                 ctcm_free_netdevice(dev);
1654         }
1655
1656         if (priv->fsm)
1657                 kfree_fsm(priv->fsm);
1658
1659         ccw_device_set_offline(cgdev->cdev[1]);
1660         ccw_device_set_offline(cgdev->cdev[0]);
1661
1662         if (priv->channel[READ])
1663                 channel_remove(priv->channel[READ]);
1664         if (priv->channel[WRITE])
1665                 channel_remove(priv->channel[WRITE]);
1666         priv->channel[READ] = priv->channel[WRITE] = NULL;
1667
1668         return 0;
1669
1670 }
1671
1672
1673 static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1674 {
1675         struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1676
1677         BUG_ON(priv == NULL);
1678
1679         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1680                         "removing device %p, proto : %d",
1681                         cgdev, priv->protocol);
1682
1683         if (cgdev->state == CCWGROUP_ONLINE)
1684                 ctcm_shutdown_device(cgdev);
1685         ctcm_remove_files(&cgdev->dev);
1686         dev_set_drvdata(&cgdev->dev, NULL);
1687         kfree(priv);
1688         put_device(&cgdev->dev);
1689 }
1690
1691 static int ctcm_pm_suspend(struct ccwgroup_device *gdev)
1692 {
1693         struct ctcm_priv *priv = dev_get_drvdata(&gdev->dev);
1694
1695         if (gdev->state == CCWGROUP_OFFLINE)
1696                 return 0;
1697         netif_device_detach(priv->channel[READ]->netdev);
1698         ctcm_close(priv->channel[READ]->netdev);
1699         ccw_device_set_offline(gdev->cdev[1]);
1700         ccw_device_set_offline(gdev->cdev[0]);
1701         return 0;
1702 }
1703
1704 static int ctcm_pm_resume(struct ccwgroup_device *gdev)
1705 {
1706         struct ctcm_priv *priv = dev_get_drvdata(&gdev->dev);
1707         int rc;
1708
1709         if (gdev->state == CCWGROUP_OFFLINE)
1710                 return 0;
1711         rc = ccw_device_set_online(gdev->cdev[1]);
1712         if (rc)
1713                 goto err_out;
1714         rc = ccw_device_set_online(gdev->cdev[0]);
1715         if (rc)
1716                 goto err_out;
1717         ctcm_open(priv->channel[READ]->netdev);
1718 err_out:
1719         netif_device_attach(priv->channel[READ]->netdev);
1720         return rc;
1721 }
1722
1723 static struct ccwgroup_driver ctcm_group_driver = {
1724         .owner       = THIS_MODULE,
1725         .name        = CTC_DRIVER_NAME,
1726         .max_slaves  = 2,
1727         .driver_id   = 0xC3E3C3D4,      /* CTCM */
1728         .probe       = ctcm_probe_device,
1729         .remove      = ctcm_remove_device,
1730         .set_online  = ctcm_new_device,
1731         .set_offline = ctcm_shutdown_device,
1732         .freeze      = ctcm_pm_suspend,
1733         .thaw        = ctcm_pm_resume,
1734         .restore     = ctcm_pm_resume,
1735 };
1736
1737
1738 /*
1739  * Module related routines
1740  */
1741
1742 /*
1743  * Prepare to be unloaded. Free IRQ's and release all resources.
1744  * This is called just before this module is unloaded. It is
1745  * not called, if the usage count is !0, so we don't need to check
1746  * for that.
1747  */
1748 static void __exit ctcm_exit(void)
1749 {
1750         unregister_cu3088_discipline(&ctcm_group_driver);
1751         ctcm_unregister_dbf_views();
1752         pr_info("CTCM driver unloaded\n");
1753 }
1754
1755 /*
1756  * Print Banner.
1757  */
1758 static void print_banner(void)
1759 {
1760         pr_info("CTCM driver initialized\n");
1761 }
1762
1763 /**
1764  * Initialize module.
1765  * This is called just after the module is loaded.
1766  *
1767  * returns 0 on success, !0 on error.
1768  */
1769 static int __init ctcm_init(void)
1770 {
1771         int ret;
1772
1773         channels = NULL;
1774
1775         ret = ctcm_register_dbf_views();
1776         if (ret) {
1777                 return ret;
1778         }
1779         ret = register_cu3088_discipline(&ctcm_group_driver);
1780         if (ret) {
1781                 ctcm_unregister_dbf_views();
1782                 pr_err("%s / register_cu3088_discipline failed, ret = %d\n",
1783                         __func__, ret);
1784                 return ret;
1785         }
1786         print_banner();
1787         return ret;
1788 }
1789
1790 module_init(ctcm_init);
1791 module_exit(ctcm_exit);
1792
1793 MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1794 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1795 MODULE_LICENSE("GPL");
1796