drivers/s390/net/ctcm_main.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright IBM Corp. 2001, 2009
   4  * Author(s):
   5  *      Original CTC driver(s):
   6  *              Fritz Elfert ([email protected])
   7  *              Dieter Wellerdiek ([email protected])
   8  *              Martin Schwidefsky ([email protected])
   9  *              Denis Joseph Barrow ([email protected])
  10  *              Jochen Roehrig ([email protected])
  11  *              Cornelia Huck <[email protected]>
  12  *      MPC additions:
  13  *              Belinda Thompson ([email protected])
  14  *              Andy Richter ([email protected])
  15  *      Revived by:
  16  *              Peter Tiedemann ([email protected])
  17  */
  18
  19 #undef DEBUG
  20 #undef DEBUGDATA
  21 #undef DEBUGCCW
  22
  23 #define KMSG_COMPONENT "ctcm"
  24 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  25
  26 #include <linux/module.h>
  27 #include <linux/init.h>
  28 #include <linux/kernel.h>
  29 #include <linux/slab.h>
  30 #include <linux/errno.h>
  31 #include <linux/types.h>
  32 #include <linux/interrupt.h>
  33 #include <linux/timer.h>
  34 #include <linux/bitops.h>
  35
  36 #include <linux/signal.h>
  37 #include <linux/string.h>
  38
  39 #include <linux/ip.h>
  40 #include <linux/if_arp.h>
  41 #include <linux/tcp.h>
  42 #include <linux/skbuff.h>
  43 #include <linux/ctype.h>
  44 #include <net/dst.h>
  45
  46 #include <linux/io.h>
  47 #include <asm/ccwdev.h>
  48 #include <asm/ccwgroup.h>
  49 #include <linux/uaccess.h>
  50
  51 #include <asm/idals.h>
  52
  53 #include "ctcm_fsms.h"
  54 #include "ctcm_main.h"
  55
  56 /* Some common global variables */
  57
  58 /*
  59  * The root device for ctcm group devices
  60  */
  61 static struct device *ctcm_root_dev;
  62
  63 /*
  64  * Linked list of all detected channels.
  65  */
  66 struct channel *channels;
  67
  68 /*
  69  * Unpack a just received skb and hand it over to
  70  * upper layers.
  71  *
  72  *  ch          The channel where this skb has been received.
  73  *  pskb        The received skb.
  74  */
  75 void ctcm_unpack_skb(struct channel *ch, struct sk_buff *pskb)
  76 {
  77         struct net_device *dev = ch->netdev;
  78         struct ctcm_priv *priv = dev->ml_priv;
  79         __u16 len = *((__u16 *) pskb->data);
  80
  81         skb_put(pskb, 2 + LL_HEADER_LENGTH);
  82         skb_pull(pskb, 2);
  83         pskb->dev = dev;
  84         pskb->ip_summed = CHECKSUM_UNNECESSARY;
  85         while (len > 0) {
  86                 struct sk_buff *skb;
  87                 int skblen;
  88                 struct ll_header *header = (struct ll_header *)pskb->data;
  89
  90                 skb_pull(pskb, LL_HEADER_LENGTH);
  91                 if ((ch->protocol == CTCM_PROTO_S390) &&
  92                     (header->type != ETH_P_IP)) {
  93                         if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
  94                                 ch->logflags |= LOG_FLAG_ILLEGALPKT;
  95                                 /*
  96                                  * Check packet type only if we stick strictly
  97                                  * to S/390's protocol of OS390. This only
  98                                  * supports IP. Otherwise allow any packet
  99                                  * type.
 100                                  */
 101                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 102                                         "%s(%s): Illegal packet type 0x%04x"
 103                                         " - dropping",
 104                                         CTCM_FUNTAIL, dev->name, header->type);
 105                         }
 106                         priv->stats.rx_dropped++;
 107                         priv->stats.rx_frame_errors++;
 108                         return;
 109                 }
 110                 pskb->protocol = cpu_to_be16(header->type);
 111                 if ((header->length <= LL_HEADER_LENGTH) ||
 112                     (len <= LL_HEADER_LENGTH)) {
 113                         if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
 114                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 115                                         "%s(%s): Illegal packet size %d(%d,%d)"
 116                                         "- dropping",
 117                                         CTCM_FUNTAIL, dev->name,
 118                                         header->length, dev->mtu, len);
 119                                 ch->logflags |= LOG_FLAG_ILLEGALSIZE;
 120                         }
 121
 122                         priv->stats.rx_dropped++;
 123                         priv->stats.rx_length_errors++;
 124                         return;
 125                 }
 126                 header->length -= LL_HEADER_LENGTH;
 127                 len -= LL_HEADER_LENGTH;
 128                 if ((header->length > skb_tailroom(pskb)) ||
 129                     (header->length > len)) {
 130                         if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 131                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 132                                         "%s(%s): Packet size %d (overrun)"
 133                                         " - dropping", CTCM_FUNTAIL,
 134                                                 dev->name, header->length);
 135                                 ch->logflags |= LOG_FLAG_OVERRUN;
 136                         }
 137
 138                         priv->stats.rx_dropped++;
 139                         priv->stats.rx_length_errors++;
 140                         return;
 141                 }
 142                 skb_put(pskb, header->length);
 143                 skb_reset_mac_header(pskb);
 144                 len -= header->length;
 145                 skb = dev_alloc_skb(pskb->len);
 146                 if (!skb) {
 147                         if (!(ch->logflags & LOG_FLAG_NOMEM)) {
 148                                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 149                                         "%s(%s): MEMORY allocation error",
 150                                                 CTCM_FUNTAIL, dev->name);
 151                                 ch->logflags |= LOG_FLAG_NOMEM;
 152                         }
 153                         priv->stats.rx_dropped++;
 154                         return;
 155                 }
 156                 skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
 157                                           pskb->len);
 158                 skb_reset_mac_header(skb);
 159                 skb->dev = pskb->dev;
 160                 skb->protocol = pskb->protocol;
 161                 pskb->ip_summed = CHECKSUM_UNNECESSARY;
 162                 skblen = skb->len;
 163                 /*
 164                  * reset logflags
 165                  */
 166                 ch->logflags = 0;
 167                 priv->stats.rx_packets++;
 168                 priv->stats.rx_bytes += skblen;
 169                 netif_rx(skb);
 170                 if (len > 0) {
 171                         skb_pull(pskb, header->length);
 172                         if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
 173                                 CTCM_DBF_DEV_NAME(TRACE, dev,
 174                                         "Overrun in ctcm_unpack_skb");
 175                                 ch->logflags |= LOG_FLAG_OVERRUN;
 176                                 return;
 177                         }
 178                         skb_put(pskb, LL_HEADER_LENGTH);
 179                 }
 180         }
 181 }
 182
 183 /*
 184  * Release a specific channel in the channel list.
 185  *
 186  *  ch          Pointer to channel struct to be released.
 187  */
 188 static void channel_free(struct channel *ch)
 189 {
 190         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s)", CTCM_FUNTAIL, ch->id);
 191         ch->flags &= ~CHANNEL_FLAGS_INUSE;
 192         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
 193 }
 194
 195 /*
 196  * Remove a specific channel in the channel list.
 197  *
 198  *  ch          Pointer to channel struct to be released.
 199  */
 200 static void channel_remove(struct channel *ch)
 201 {
 202         struct channel **c = &channels;
 203         char chid[CTCM_ID_SIZE];
 204         int ok = 0;
 205
 206         if (ch == NULL)
 207                 return;
 208         else
 209                 strscpy(chid, ch->id, sizeof(chid));
 210
 211         channel_free(ch);
 212         while (*c) {
 213                 if (*c == ch) {
 214                         *c = ch->next;
 215                         fsm_deltimer(&ch->timer);
 216                         if (IS_MPC(ch))
 217                                 fsm_deltimer(&ch->sweep_timer);
 218
 219                         kfree_fsm(ch->fsm);
 220                         clear_normalized_cda(&ch->ccw[4]);
 221                         if (ch->trans_skb != NULL) {
 222                                 clear_normalized_cda(&ch->ccw[1]);
 223                                 dev_kfree_skb_any(ch->trans_skb);
 224                         }
 225                         if (IS_MPC(ch)) {
 226                                 tasklet_kill(&ch->ch_tasklet);
 227                                 tasklet_kill(&ch->ch_disc_tasklet);
 228                                 kfree(ch->discontact_th);
 229                         }
 230                         kfree(ch->ccw);
 231                         kfree(ch->irb);
 232                         kfree(ch);
 233                         ok = 1;
 234                         break;
 235                 }
 236                 c = &((*c)->next);
 237         }
 238
 239         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
 240                         chid, ok ? "OK" : "failed");
 241 }
 242
 243 /*
 244  * Get a specific channel from the channel list.
 245  *
 246  *  type        Type of channel we are interested in.
 247  *  id          Id of channel we are interested in.
 248  *  direction   Direction we want to use this channel for.
 249  *
 250  * returns Pointer to a channel or NULL if no matching channel available.
 251  */
 252 static struct channel *channel_get(enum ctcm_channel_types type,
 253                                         char *id, int direction)
 254 {
 255         struct channel *ch = channels;
 256
 257         while (ch && (strncmp(ch->id, id, CTCM_ID_SIZE) || (ch->type != type)))
 258                 ch = ch->next;
 259         if (!ch) {
 260                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 261                                 "%s(%d, %s, %d) not found in channel list\n",
 262                                 CTCM_FUNTAIL, type, id, direction);
 263         } else {
 264                 if (ch->flags & CHANNEL_FLAGS_INUSE)
 265                         ch = NULL;
 266                 else {
 267                         ch->flags |= CHANNEL_FLAGS_INUSE;
 268                         ch->flags &= ~CHANNEL_FLAGS_RWMASK;
 269                         ch->flags |= (direction == CTCM_WRITE)
 270                             ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
 271                         fsm_newstate(ch->fsm, CTC_STATE_STOPPED);
 272                 }
 273         }
 274         return ch;
 275 }
 276
 277 static long ctcm_check_irb_error(struct ccw_device *cdev, struct irb *irb)
 278 {
 279         if (!IS_ERR(irb))
 280                 return 0;
 281
 282         CTCM_DBF_TEXT_(ERROR, CTC_DBF_WARN,
 283                         "irb error %ld on device %s\n",
 284                                 PTR_ERR(irb), dev_name(&cdev->dev));
 285
 286         switch (PTR_ERR(irb)) {
 287         case -EIO:
 288                 dev_err(&cdev->dev,
 289                         "An I/O-error occurred on the CTCM device\n");
 290                 break;
 291         case -ETIMEDOUT:
 292                 dev_err(&cdev->dev,
 293                         "An adapter hardware operation timed out\n");
 294                 break;
 295         default:
 296                 dev_err(&cdev->dev,
 297                         "An error occurred on the adapter hardware\n");
 298         }
 299         return PTR_ERR(irb);
 300 }
 301
 302
 303 /*
 304  * Check sense of a unit check.
 305  *
 306  *  ch          The channel, the sense code belongs to.
 307  *  sense       The sense code to inspect.
 308  */
 309 static void ccw_unit_check(struct channel *ch, __u8 sense)
 310 {
 311         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
 312                         "%s(%s): %02x",
 313                                 CTCM_FUNTAIL, ch->id, sense);
 314
 315         if (sense & SNS0_INTERVENTION_REQ) {
 316                 if (sense & 0x01) {
 317                         if (ch->sense_rc != 0x01) {
 318                                 pr_notice(
 319                                         "%s: The communication peer has "
 320                                         "disconnected\n", ch->id);
 321                                 ch->sense_rc = 0x01;
 322                         }
 323                         fsm_event(ch->fsm, CTC_EVENT_UC_RCRESET, ch);
 324                 } else {
 325                         if (ch->sense_rc != SNS0_INTERVENTION_REQ) {
 326                                 pr_notice(
 327                                         "%s: The remote operating system is "
 328                                         "not available\n", ch->id);
 329                                 ch->sense_rc = SNS0_INTERVENTION_REQ;
 330                         }
 331                         fsm_event(ch->fsm, CTC_EVENT_UC_RSRESET, ch);
 332                 }
 333         } else if (sense & SNS0_EQUIPMENT_CHECK) {
 334                 if (sense & SNS0_BUS_OUT_CHECK) {
 335                         if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 336                                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 337                                         "%s(%s): remote HW error %02x",
 338                                                 CTCM_FUNTAIL, ch->id, sense);
 339                                 ch->sense_rc = SNS0_BUS_OUT_CHECK;
 340                         }
 341                         fsm_event(ch->fsm, CTC_EVENT_UC_HWFAIL, ch);
 342                 } else {
 343                         if (ch->sense_rc != SNS0_EQUIPMENT_CHECK) {
 344                                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 345                                         "%s(%s): remote read parity error %02x",
 346                                                 CTCM_FUNTAIL, ch->id, sense);
 347                                 ch->sense_rc = SNS0_EQUIPMENT_CHECK;
 348                         }
 349                         fsm_event(ch->fsm, CTC_EVENT_UC_RXPARITY, ch);
 350                 }
 351         } else if (sense & SNS0_BUS_OUT_CHECK) {
 352                 if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 353                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 354                                 "%s(%s): BUS OUT error %02x",
 355                                         CTCM_FUNTAIL, ch->id, sense);
 356                         ch->sense_rc = SNS0_BUS_OUT_CHECK;
 357                 }
 358                 if (sense & 0x04)       /* data-streaming timeout */
 359                         fsm_event(ch->fsm, CTC_EVENT_UC_TXTIMEOUT, ch);
 360                 else                    /* Data-transfer parity error */
 361                         fsm_event(ch->fsm, CTC_EVENT_UC_TXPARITY, ch);
 362         } else if (sense & SNS0_CMD_REJECT) {
 363                 if (ch->sense_rc != SNS0_CMD_REJECT) {
 364                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 365                                 "%s(%s): Command rejected",
 366                                                 CTCM_FUNTAIL, ch->id);
 367                         ch->sense_rc = SNS0_CMD_REJECT;
 368                 }
 369         } else if (sense == 0) {
 370                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 371                         "%s(%s): Unit check ZERO",
 372                                         CTCM_FUNTAIL, ch->id);
 373                 fsm_event(ch->fsm, CTC_EVENT_UC_ZERO, ch);
 374         } else {
 375                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 376                         "%s(%s): Unit check code %02x unknown",
 377                                         CTCM_FUNTAIL, ch->id, sense);
 378                 fsm_event(ch->fsm, CTC_EVENT_UC_UNKNOWN, ch);
 379         }
 380 }
 381
 382 int ctcm_ch_alloc_buffer(struct channel *ch)
 383 {
 384         clear_normalized_cda(&ch->ccw[1]);
 385         ch->trans_skb = __dev_alloc_skb(ch->max_bufsize, GFP_ATOMIC | GFP_DMA);
 386         if (ch->trans_skb == NULL) {
 387                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 388                         "%s(%s): %s trans_skb allocation error",
 389                         CTCM_FUNTAIL, ch->id,
 390                         (CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
 391                                 "RX" : "TX");
 392                 return -ENOMEM;
 393         }
 394
 395         ch->ccw[1].count = ch->max_bufsize;
 396         if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
 397                 dev_kfree_skb(ch->trans_skb);
 398                 ch->trans_skb = NULL;
 399                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 400                         "%s(%s): %s set norm_cda failed",
 401                         CTCM_FUNTAIL, ch->id,
 402                         (CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
 403                                 "RX" : "TX");
 404                 return -ENOMEM;
 405         }
 406
 407         ch->ccw[1].count = 0;
 408         ch->trans_skb_data = ch->trans_skb->data;
 409         ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
 410         return 0;
 411 }
 412
 413 /*
 414  * Interface API for upper network layers
 415  */
 416
 417 /*
 418  * Open an interface.
 419  * Called from generic network layer when ifconfig up is run.
 420  *
 421  *  dev         Pointer to interface struct.
 422  *
 423  * returns 0 on success, -ERRNO on failure. (Never fails.)
 424  */
 425 int ctcm_open(struct net_device *dev)
 426 {
 427         struct ctcm_priv *priv = dev->ml_priv;
 428
 429         CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 430         if (!IS_MPC(priv))
 431                 fsm_event(priv->fsm,    DEV_EVENT_START, dev);
 432         return 0;
 433 }
 434
 435 /*
 436  * Close an interface.
 437  * Called from generic network layer when ifconfig down is run.
 438  *
 439  *  dev         Pointer to interface struct.
 440  *
 441  * returns 0 on success, -ERRNO on failure. (Never fails.)
 442  */
 443 int ctcm_close(struct net_device *dev)
 444 {
 445         struct ctcm_priv *priv = dev->ml_priv;
 446
 447         CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 448         if (!IS_MPC(priv))
 449                 fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
 450         return 0;
 451 }
 452
 453
 454 /*
 455  * Transmit a packet.
 456  * This is a helper function for ctcm_tx().
 457  *
 458  *  ch          Channel to be used for sending.
 459  *  skb         Pointer to struct sk_buff of packet to send.
 460  *            The linklevel header has already been set up
 461  *            by ctcm_tx().
 462  *
 463  * returns 0 on success, -ERRNO on failure. (Never fails.)
 464  */
 465 static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
 466 {
 467         unsigned long saveflags;
 468         struct ll_header header;
 469         int rc = 0;
 470         __u16 block_len;
 471         int ccw_idx;
 472         struct sk_buff *nskb;
 473         unsigned long hi;
 474
 475         /* we need to acquire the lock for testing the state
 476          * otherwise we can have an IRQ changing the state to
 477          * TXIDLE after the test but before acquiring the lock.
 478          */
 479         spin_lock_irqsave(&ch->collect_lock, saveflags);
 480         if (fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) {
 481                 int l = skb->len + LL_HEADER_LENGTH;
 482
 483                 if (ch->collect_len + l > ch->max_bufsize - 2) {
 484                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 485                         return -EBUSY;
 486                 } else {
 487                         refcount_inc(&skb->users);
 488                         header.length = l;
 489                         header.type = be16_to_cpu(skb->protocol);
 490                         header.unused = 0;
 491                         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
 492                                LL_HEADER_LENGTH);
 493                         skb_queue_tail(&ch->collect_queue, skb);
 494                         ch->collect_len += l;
 495                 }
 496                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 497                 goto done;
 498         }
 499         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 500         /*
 501          * Protect skb against beeing free'd by upper
 502          * layers.
 503          */
 504         refcount_inc(&skb->users);
 505         ch->prof.txlen += skb->len;
 506         header.length = skb->len + LL_HEADER_LENGTH;
 507         header.type = be16_to_cpu(skb->protocol);
 508         header.unused = 0;
 509         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header, LL_HEADER_LENGTH);
 510         block_len = skb->len + 2;
 511         *((__u16 *)skb_push(skb, 2)) = block_len;
 512
 513         /*
 514          * IDAL support in CTCM is broken, so we have to
 515          * care about skb's above 2G ourselves.
 516          */
 517         hi = ((unsigned long)skb_tail_pointer(skb) + LL_HEADER_LENGTH) >> 31;
 518         if (hi) {
 519                 nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 520                 if (!nskb) {
 521                         refcount_dec(&skb->users);
 522                         skb_pull(skb, LL_HEADER_LENGTH + 2);
 523                         ctcm_clear_busy(ch->netdev);
 524                         return -ENOMEM;
 525                 } else {
 526                         skb_put_data(nskb, skb->data, skb->len);
 527                         refcount_inc(&nskb->users);
 528                         refcount_dec(&skb->users);
 529                         dev_kfree_skb_irq(skb);
 530                         skb = nskb;
 531                 }
 532         }
 533
 534         ch->ccw[4].count = block_len;
 535         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 536                 /*
 537                  * idal allocation failed, try via copying to
 538                  * trans_skb. trans_skb usually has a pre-allocated
 539                  * idal.
 540                  */
 541                 if (ctcm_checkalloc_buffer(ch)) {
 542                         /*
 543                          * Remove our header. It gets added
 544                          * again on retransmit.
 545                          */
 546                         refcount_dec(&skb->users);
 547                         skb_pull(skb, LL_HEADER_LENGTH + 2);
 548                         ctcm_clear_busy(ch->netdev);
 549                         return -ENOMEM;
 550                 }
 551
 552                 skb_reset_tail_pointer(ch->trans_skb);
 553                 ch->trans_skb->len = 0;
 554                 ch->ccw[1].count = skb->len;
 555                 skb_copy_from_linear_data(skb,
 556                                 skb_put(ch->trans_skb, skb->len), skb->len);
 557                 refcount_dec(&skb->users);
 558                 dev_kfree_skb_irq(skb);
 559                 ccw_idx = 0;
 560         } else {
 561                 skb_queue_tail(&ch->io_queue, skb);
 562                 ccw_idx = 3;
 563         }
 564         if (do_debug_ccw)
 565                 ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 566                                         sizeof(struct ccw1) * 3);
 567         ch->retry = 0;
 568         fsm_newstate(ch->fsm, CTC_STATE_TX);
 569         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 570         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 571         ch->prof.send_stamp = jiffies;
 572         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
 573         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 574         if (ccw_idx == 3)
 575                 ch->prof.doios_single++;
 576         if (rc != 0) {
 577                 fsm_deltimer(&ch->timer);
 578                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
 579                 if (ccw_idx == 3)
 580                         skb_dequeue_tail(&ch->io_queue);
 581                 /*
 582                  * Remove our header. It gets added
 583                  * again on retransmit.
 584                  */
 585                 skb_pull(skb, LL_HEADER_LENGTH + 2);
 586         } else if (ccw_idx == 0) {
 587                 struct net_device *dev = ch->netdev;
 588                 struct ctcm_priv *priv = dev->ml_priv;
 589                 priv->stats.tx_packets++;
 590                 priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 591         }
 592 done:
 593         ctcm_clear_busy(ch->netdev);
 594         return rc;
 595 }
 596
 597 static void ctcmpc_send_sweep_req(struct channel *rch)
 598 {
 599         struct net_device *dev = rch->netdev;
 600         struct ctcm_priv *priv;
 601         struct mpc_group *grp;
 602         struct th_sweep *header;
 603         struct sk_buff *sweep_skb;
 604         struct channel *ch;
 605         /* int rc = 0; */
 606
 607         priv = dev->ml_priv;
 608         grp = priv->mpcg;
 609         ch = priv->channel[CTCM_WRITE];
 610
 611         /* sweep processing is not complete until response and request */
 612         /* has completed for all read channels in group                */
 613         if (grp->in_sweep == 0) {
 614                 grp->in_sweep = 1;
 615                 grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
 616                 grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
 617         }
 618
 619         sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
 620
 621         if (sweep_skb == NULL)  {
 622                 /* rc = -ENOMEM; */
 623                                 goto nomem;
 624         }
 625
 626         header = skb_put_zero(sweep_skb, TH_SWEEP_LENGTH);
 627         header->th.th_ch_flag   = TH_SWEEP_REQ;  /* 0x0f */
 628         header->sw.th_last_seq  = ch->th_seq_num;
 629
 630         netif_trans_update(dev);
 631         skb_queue_tail(&ch->sweep_queue, sweep_skb);
 632
 633         fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
 634
 635         return;
 636
 637 nomem:
 638         grp->in_sweep = 0;
 639         ctcm_clear_busy(dev);
 640         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 641
 642         return;
 643 }
 644
 645 /*
 646  * MPC mode version of transmit_skb
 647  */
 648 static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
 649 {
 650         struct pdu *p_header;
 651         struct net_device *dev = ch->netdev;
 652         struct ctcm_priv *priv = dev->ml_priv;
 653         struct mpc_group *grp = priv->mpcg;
 654         struct th_header *header;
 655         struct sk_buff *nskb;
 656         int rc = 0;
 657         int ccw_idx;
 658         unsigned long hi;
 659         unsigned long saveflags = 0;    /* avoids compiler warning */
 660
 661         CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
 662                         __func__, dev->name, smp_processor_id(), ch,
 663                                         ch->id, fsm_getstate_str(ch->fsm));
 664
 665         if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
 666                 spin_lock_irqsave(&ch->collect_lock, saveflags);
 667                 refcount_inc(&skb->users);
 668
 669                 p_header = skb_push(skb, PDU_HEADER_LENGTH);
 670                 p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
 671                 p_header->pdu_proto = 0x01;
 672                 if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
 673                         p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
 674                 } else {
 675                         p_header->pdu_flag = PDU_FIRST;
 676                 }
 677                 p_header->pdu_seq = 0;
 678
 679                 CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
 680                                 "pdu header and data for up to 32 bytes:\n",
 681                                 __func__, dev->name, skb->len);
 682                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 683
 684                 skb_queue_tail(&ch->collect_queue, skb);
 685                 ch->collect_len += skb->len;
 686
 687                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 688                 goto done;
 689         }
 690
 691         /*
 692          * Protect skb against beeing free'd by upper
 693          * layers.
 694          */
 695         refcount_inc(&skb->users);
 696
 697         /*
 698          * IDAL support in CTCM is broken, so we have to
 699          * care about skb's above 2G ourselves.
 700          */
 701         hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
 702         if (hi) {
 703                 nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 704                 if (!nskb) {
 705                         goto nomem_exit;
 706                 } else {
 707                         skb_put_data(nskb, skb->data, skb->len);
 708                         refcount_inc(&nskb->users);
 709                         refcount_dec(&skb->users);
 710                         dev_kfree_skb_irq(skb);
 711                         skb = nskb;
 712                 }
 713         }
 714
 715         p_header = skb_push(skb, PDU_HEADER_LENGTH);
 716         p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
 717         p_header->pdu_proto = 0x01;
 718         p_header->pdu_seq = 0;
 719         if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
 720                 p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
 721         } else {
 722                 p_header->pdu_flag = PDU_FIRST;
 723         }
 724
 725         if (ch->collect_len > 0) {
 726                 spin_lock_irqsave(&ch->collect_lock, saveflags);
 727                 skb_queue_tail(&ch->collect_queue, skb);
 728                 ch->collect_len += skb->len;
 729                 skb = skb_dequeue(&ch->collect_queue);
 730                 ch->collect_len -= skb->len;
 731                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 732         }
 733
 734         p_header = (struct pdu *)skb->data;
 735         p_header->pdu_flag |= PDU_LAST;
 736
 737         ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
 738
 739         /* put the TH on the packet */
 740         header = skb_push(skb, TH_HEADER_LENGTH);
 741         memset(header, 0, TH_HEADER_LENGTH);
 742
 743         header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
 744         ch->th_seq_num++;
 745         header->th_seq_num = ch->th_seq_num;
 746
 747         CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
 748                        __func__, dev->name, ch->th_seq_num);
 749
 750         CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
 751                         "up to 32 bytes sent to vtam:\n",
 752                                 __func__, dev->name, skb->len);
 753         CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 754
 755         ch->ccw[4].count = skb->len;
 756         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 757                 /*
 758                  * idal allocation failed, try via copying to trans_skb.
 759                  * trans_skb usually has a pre-allocated idal.
 760                  */
 761                 if (ctcm_checkalloc_buffer(ch)) {
 762                         /*
 763                          * Remove our header.
 764                          * It gets added again on retransmit.
 765                          */
 766                                 goto nomem_exit;
 767                 }
 768
 769                 skb_reset_tail_pointer(ch->trans_skb);
 770                 ch->trans_skb->len = 0;
 771                 ch->ccw[1].count = skb->len;
 772                 skb_put_data(ch->trans_skb, skb->data, skb->len);
 773                 refcount_dec(&skb->users);
 774                 dev_kfree_skb_irq(skb);
 775                 ccw_idx = 0;
 776                 CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
 777                                 "up to 32 bytes sent to vtam:\n",
 778                                 __func__, dev->name, ch->trans_skb->len);
 779                 CTCM_D3_DUMP((char *)ch->trans_skb->data,
 780                                 min_t(int, 32, ch->trans_skb->len));
 781         } else {
 782                 skb_queue_tail(&ch->io_queue, skb);
 783                 ccw_idx = 3;
 784         }
 785         ch->retry = 0;
 786         fsm_newstate(ch->fsm, CTC_STATE_TX);
 787         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 788
 789         if (do_debug_ccw)
 790                 ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 791                                         sizeof(struct ccw1) * 3);
 792
 793         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 794         ch->prof.send_stamp = jiffies;
 795         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
 796         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 797         if (ccw_idx == 3)
 798                 ch->prof.doios_single++;
 799         if (rc != 0) {
 800                 fsm_deltimer(&ch->timer);
 801                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
 802                 if (ccw_idx == 3)
 803                         skb_dequeue_tail(&ch->io_queue);
 804         } else if (ccw_idx == 0) {
 805                 priv->stats.tx_packets++;
 806                 priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
 807         }
 808         if (ch->th_seq_num > 0xf0000000)        /* Chose at random. */
 809                 ctcmpc_send_sweep_req(ch);
 810
 811         goto done;
 812 nomem_exit:
 813         CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
 814                         "%s(%s): MEMORY allocation ERROR\n",
 815                         CTCM_FUNTAIL, ch->id);
 816         rc = -ENOMEM;
 817         refcount_dec(&skb->users);
 818         dev_kfree_skb_any(skb);
 819         fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
 820 done:
 821         CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
 822         return rc;
 823 }
 824
 825 /*
 826  * Start transmission of a packet.
 827  * Called from generic network device layer.
 828  */
 829 /* first merge version - leaving both functions separated */
 830 static netdev_tx_t ctcm_tx(struct sk_buff *skb, struct net_device *dev)
 831 {
 832         struct ctcm_priv *priv = dev->ml_priv;
 833
 834         if (skb == NULL) {
 835                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 836                                 "%s(%s): NULL sk_buff passed",
 837                                         CTCM_FUNTAIL, dev->name);
 838                 priv->stats.tx_dropped++;
 839                 return NETDEV_TX_OK;
 840         }
 841         if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
 842                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 843                         "%s(%s): Got sk_buff with head room < %ld bytes",
 844                         CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
 845                 dev_kfree_skb(skb);
 846                 priv->stats.tx_dropped++;
 847                 return NETDEV_TX_OK;
 848         }
 849
 850         /*
 851          * If channels are not running, try to restart them
 852          * and throw away packet.
 853          */
 854         if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
 855                 fsm_event(priv->fsm, DEV_EVENT_START, dev);
 856                 dev_kfree_skb(skb);
 857                 priv->stats.tx_dropped++;
 858                 priv->stats.tx_errors++;
 859                 priv->stats.tx_carrier_errors++;
 860                 return NETDEV_TX_OK;
 861         }
 862
 863         if (ctcm_test_and_set_busy(dev))
 864                 return NETDEV_TX_BUSY;
 865
 866         netif_trans_update(dev);
 867         if (ctcm_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0)
 868                 return NETDEV_TX_BUSY;
 869         return NETDEV_TX_OK;
 870 }
 871
 872 /* unmerged MPC variant of ctcm_tx */
 873 static netdev_tx_t ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
 874 {
 875         int len = 0;
 876         struct ctcm_priv *priv = dev->ml_priv;
 877         struct mpc_group *grp  = priv->mpcg;
 878         struct sk_buff *newskb = NULL;
 879
 880         /*
 881          * Some sanity checks ...
 882          */
 883         if (skb == NULL) {
 884                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 885                         "%s(%s): NULL sk_buff passed",
 886                                         CTCM_FUNTAIL, dev->name);
 887                 priv->stats.tx_dropped++;
 888                 goto done;
 889         }
 890         if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
 891                 CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 892                         "%s(%s): Got sk_buff with head room < %ld bytes",
 893                         CTCM_FUNTAIL, dev->name,
 894                                 TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 895
 896                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 897
 898                 len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 899                 newskb = __dev_alloc_skb(len, GFP_ATOMIC | GFP_DMA);
 900
 901                 if (!newskb) {
 902                         CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 903                                 "%s: %s: __dev_alloc_skb failed",
 904                                                 __func__, dev->name);
 905
 906                         dev_kfree_skb_any(skb);
 907                         priv->stats.tx_dropped++;
 908                         priv->stats.tx_errors++;
 909                         priv->stats.tx_carrier_errors++;
 910                         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 911                         goto done;
 912                 }
 913                 newskb->protocol = skb->protocol;
 914                 skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 915                 skb_put_data(newskb, skb->data, skb->len);
 916                 dev_kfree_skb_any(skb);
 917                 skb = newskb;
 918         }
 919
 920         /*
 921          * If channels are not running,
 922          * notify anybody about a link failure and throw
 923          * away packet.
 924          */
 925         if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
 926            (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
 927                 dev_kfree_skb_any(skb);
 928                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 929                         "%s(%s): inactive MPCGROUP - dropped",
 930                                         CTCM_FUNTAIL, dev->name);
 931                 priv->stats.tx_dropped++;
 932                 priv->stats.tx_errors++;
 933                 priv->stats.tx_carrier_errors++;
 934                 goto done;
 935         }
 936
 937         if (ctcm_test_and_set_busy(dev)) {
 938                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 939                         "%s(%s): device busy - dropped",
 940                                         CTCM_FUNTAIL, dev->name);
 941                 dev_kfree_skb_any(skb);
 942                 priv->stats.tx_dropped++;
 943                 priv->stats.tx_errors++;
 944                 priv->stats.tx_carrier_errors++;
 945                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 946                 goto done;
 947         }
 948
 949         netif_trans_update(dev);
 950         if (ctcmpc_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0) {
 951                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 952                         "%s(%s): device error - dropped",
 953                                         CTCM_FUNTAIL, dev->name);
 954                 dev_kfree_skb_any(skb);
 955                 priv->stats.tx_dropped++;
 956                 priv->stats.tx_errors++;
 957                 priv->stats.tx_carrier_errors++;
 958                 ctcm_clear_busy(dev);
 959                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 960                 goto done;
 961         }
 962         ctcm_clear_busy(dev);
 963 done:
 964         if (do_debug)
 965                 MPC_DBF_DEV_NAME(TRACE, dev, "exit");
 966
 967         return NETDEV_TX_OK;    /* handle freeing of skb here */
 968 }
 969
 970
 971 /*
 972  * Sets MTU of an interface.
 973  *
 974  *  dev         Pointer to interface struct.
 975  *  new_mtu     The new MTU to use for this interface.
 976  *
 977  * returns 0 on success, -EINVAL if MTU is out of valid range.
 978  *         (valid range is 576 .. 65527). If VM is on the
 979  *         remote side, maximum MTU is 32760, however this is
 980  *         not checked here.
 981  */
 982 static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
 983 {
 984         struct ctcm_priv *priv;
 985         int max_bufsize;
 986
 987         priv = dev->ml_priv;
 988         max_bufsize = priv->channel[CTCM_READ]->max_bufsize;
 989
 990         if (IS_MPC(priv)) {
 991                 if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
 992                         return -EINVAL;
 993                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 994         } else {
 995                 if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
 996                         return -EINVAL;
 997                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
 998         }
 999         dev->mtu = new_mtu;
1000         return 0;
1001 }
1002
1003 /*
1004  * Returns interface statistics of a device.
1005  *
1006  *  dev         Pointer to interface struct.
1007  *
1008  * returns Pointer to stats struct of this interface.
1009  */
1010 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1011 {
1012         return &((struct ctcm_priv *)dev->ml_priv)->stats;
1013 }
1014
1015 static void ctcm_free_netdevice(struct net_device *dev)
1016 {
1017         struct ctcm_priv *priv;
1018         struct mpc_group *grp;
1019
1020         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1021                         "%s(%s)", CTCM_FUNTAIL, dev->name);
1022         priv = dev->ml_priv;
1023         if (priv) {
1024                 grp = priv->mpcg;
1025                 if (grp) {
1026                         if (grp->fsm)
1027                                 kfree_fsm(grp->fsm);
1028                         dev_kfree_skb(grp->xid_skb);
1029                         dev_kfree_skb(grp->rcvd_xid_skb);
1030                         tasklet_kill(&grp->mpc_tasklet2);
1031                         kfree(grp);
1032                         priv->mpcg = NULL;
1033                 }
1034                 if (priv->fsm) {
1035                         kfree_fsm(priv->fsm);
1036                         priv->fsm = NULL;
1037                 }
1038                 kfree(priv->xid);
1039                 priv->xid = NULL;
1040         /*
1041          * Note: kfree(priv); is done in "opposite" function of
1042          * allocator function probe_device which is remove_device.
1043          */
1044         }
1045 #ifdef MODULE
1046         free_netdev(dev);
1047 #endif
1048 }
1049
1050 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1051
1052 static const struct net_device_ops ctcm_netdev_ops = {
1053         .ndo_open               = ctcm_open,
1054         .ndo_stop               = ctcm_close,
1055         .ndo_get_stats          = ctcm_stats,
1056         .ndo_change_mtu         = ctcm_change_mtu,
1057         .ndo_start_xmit         = ctcm_tx,
1058 };
1059
1060 static const struct net_device_ops ctcm_mpc_netdev_ops = {
1061         .ndo_open               = ctcm_open,
1062         .ndo_stop               = ctcm_close,
1063         .ndo_get_stats          = ctcm_stats,
1064         .ndo_change_mtu         = ctcm_change_mtu,
1065         .ndo_start_xmit         = ctcmpc_tx,
1066 };
1067
1068 static void ctcm_dev_setup(struct net_device *dev)
1069 {
1070         dev->type = ARPHRD_SLIP;
1071         dev->tx_queue_len = 100;
1072         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1073         dev->min_mtu = 576;
1074         dev->max_mtu = 65527;
1075 }
1076
1077 /*
1078  * Initialize everything of the net device except the name and the
1079  * channel structs.
1080  */
1081 static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1082 {
1083         struct net_device *dev;
1084         struct mpc_group *grp;
1085         if (!priv)
1086                 return NULL;
1087
1088         if (IS_MPC(priv))
1089                 dev = alloc_netdev(0, MPC_DEVICE_GENE, NET_NAME_UNKNOWN,
1090                                    ctcm_dev_setup);
1091         else
1092                 dev = alloc_netdev(0, CTC_DEVICE_GENE, NET_NAME_UNKNOWN,
1093                                    ctcm_dev_setup);
1094
1095         if (!dev) {
1096                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1097                         "%s: MEMORY allocation ERROR",
1098                         CTCM_FUNTAIL);
1099                 return NULL;
1100         }
1101         dev->ml_priv = priv;
1102         priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1103                                 CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1104                                 dev_fsm, dev_fsm_len, GFP_KERNEL);
1105         if (priv->fsm == NULL) {
1106                 CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1107                 free_netdev(dev);
1108                 return NULL;
1109         }
1110         fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1111         fsm_settimer(priv->fsm, &priv->restart_timer);
1112
1113         if (IS_MPC(priv)) {
1114                 /*  MPC Group Initializations  */
1115                 grp = ctcmpc_init_mpc_group(priv);
1116                 if (grp == NULL) {
1117                         MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1118                         free_netdev(dev);
1119                         return NULL;
1120                 }
1121                 tasklet_init(&grp->mpc_tasklet2,
1122                                 mpc_group_ready, (unsigned long)dev);
1123                 dev->mtu = MPC_BUFSIZE_DEFAULT -
1124                                 TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1125
1126                 dev->netdev_ops = &ctcm_mpc_netdev_ops;
1127                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1128                 priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1129         } else {
1130                 dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1131                 dev->netdev_ops = &ctcm_netdev_ops;
1132                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1133         }
1134
1135         CTCMY_DBF_DEV(SETUP, dev, "finished");
1136
1137         return dev;
1138 }
1139
1140 /*
1141  * Main IRQ handler.
1142  *
1143  *  cdev        The ccw_device the interrupt is for.
1144  *  intparm     interruption parameter.
1145  *  irb         interruption response block.
1146  */
1147 static void ctcm_irq_handler(struct ccw_device *cdev,
1148                                 unsigned long intparm, struct irb *irb)
1149 {
1150         struct channel          *ch;
1151         struct net_device       *dev;
1152         struct ctcm_priv        *priv;
1153         struct ccwgroup_device  *cgdev;
1154         int cstat;
1155         int dstat;
1156
1157         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1158                 "Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1159
1160         if (ctcm_check_irb_error(cdev, irb))
1161                 return;
1162
1163         cgdev = dev_get_drvdata(&cdev->dev);
1164
1165         cstat = irb->scsw.cmd.cstat;
1166         dstat = irb->scsw.cmd.dstat;
1167
1168         /* Check for unsolicited interrupts. */
1169         if (cgdev == NULL) {
1170                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1171                         "%s(%s) unsolicited irq: c-%02x d-%02x\n",
1172                         CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1173                 dev_warn(&cdev->dev,
1174                         "The adapter received a non-specific IRQ\n");
1175                 return;
1176         }
1177
1178         priv = dev_get_drvdata(&cgdev->dev);
1179
1180         /* Try to extract channel from driver data. */
1181         if (priv->channel[CTCM_READ]->cdev == cdev)
1182                 ch = priv->channel[CTCM_READ];
1183         else if (priv->channel[CTCM_WRITE]->cdev == cdev)
1184                 ch = priv->channel[CTCM_WRITE];
1185         else {
1186                 dev_err(&cdev->dev,
1187                         "%s: Internal error: Can't determine channel for "
1188                         "interrupt device %s\n",
1189                         __func__, dev_name(&cdev->dev));
1190                         /* Explain: inconsistent internal structures */
1191                 return;
1192         }
1193
1194         dev = ch->netdev;
1195         if (dev == NULL) {
1196                 dev_err(&cdev->dev,
1197                         "%s Internal error: net_device is NULL, ch = 0x%p\n",
1198                         __func__, ch);
1199                         /* Explain: inconsistent internal structures */
1200                 return;
1201         }
1202
1203         /* Copy interruption response block. */
1204         memcpy(ch->irb, irb, sizeof(struct irb));
1205
1206         /* Issue error message and return on subchannel error code */
1207         if (irb->scsw.cmd.cstat) {
1208                 fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1209                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1210                         "%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1211                                 CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1212                 dev_warn(&cdev->dev,
1213                                 "A check occurred on the subchannel\n");
1214                 return;
1215         }
1216
1217         /* Check the reason-code of a unit check */
1218         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1219                 if ((irb->ecw[0] & ch->sense_rc) == 0)
1220                         /* print it only once */
1221                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1222                                 "%s(%s): sense=%02x, ds=%02x",
1223                                 CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1224                 ccw_unit_check(ch, irb->ecw[0]);
1225                 return;
1226         }
1227         if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1228                 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1229                         fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1230                 else
1231                         fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1232                 return;
1233         }
1234         if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1235                 fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1236                 return;
1237         }
1238         if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1239             (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1240             (irb->scsw.cmd.stctl ==
1241              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1242                 fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1243         else
1244                 fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1245
1246 }
1247
1248 static const struct device_type ctcm_devtype = {
1249         .name = "ctcm",
1250         .groups = ctcm_attr_groups,
1251 };
1252
1253 /*
1254  * Add ctcm specific attributes.
1255  * Add ctcm private data.
1256  *
1257  *  cgdev       pointer to ccwgroup_device just added
1258  *
1259  * returns 0 on success, !0 on failure.
1260  */
1261 static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1262 {
1263         struct ctcm_priv *priv;
1264
1265         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1266                         "%s %p",
1267                         __func__, cgdev);
1268
1269         if (!get_device(&cgdev->dev))
1270                 return -ENODEV;
1271
1272         priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1273         if (!priv) {
1274                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1275                         "%s: memory allocation failure",
1276                         CTCM_FUNTAIL);
1277                 put_device(&cgdev->dev);
1278                 return -ENOMEM;
1279         }
1280         priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1281         cgdev->cdev[0]->handler = ctcm_irq_handler;
1282         cgdev->cdev[1]->handler = ctcm_irq_handler;
1283         dev_set_drvdata(&cgdev->dev, priv);
1284         cgdev->dev.type = &ctcm_devtype;
1285
1286         return 0;
1287 }
1288
1289 /*
1290  * Add a new channel to the list of channels.
1291  * Keeps the channel list sorted.
1292  *
1293  *  cdev        The ccw_device to be added.
1294  *  type        The type class of the new channel.
1295  *  priv        Points to the private data of the ccwgroup_device.
1296  *
1297  * returns 0 on success, !0 on error.
1298  */
1299 static int add_channel(struct ccw_device *cdev, enum ctcm_channel_types type,
1300                                 struct ctcm_priv *priv)
1301 {
1302         struct channel **c = &channels;
1303         struct channel *ch;
1304         int ccw_num;
1305         int rc = 0;
1306
1307         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1308                 "%s(%s), type %d, proto %d",
1309                         __func__, dev_name(&cdev->dev), type, priv->protocol);
1310
1311         ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1312         if (ch == NULL)
1313                 return -ENOMEM;
1314
1315         ch->protocol = priv->protocol;
1316         if (IS_MPC(priv)) {
1317                 ch->discontact_th = kzalloc(TH_HEADER_LENGTH, GFP_KERNEL);
1318                 if (ch->discontact_th == NULL)
1319                                         goto nomem_return;
1320
1321                 ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1322                 tasklet_init(&ch->ch_disc_tasklet,
1323                         mpc_action_send_discontact, (unsigned long)ch);
1324
1325                 tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1326                 ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1327                 ccw_num = 17;
1328         } else
1329                 ccw_num = 8;
1330
1331         ch->ccw = kcalloc(ccw_num, sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1332         if (ch->ccw == NULL)
1333                                         goto nomem_return;
1334
1335         ch->cdev = cdev;
1336         scnprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1337         ch->type = type;
1338
1339         /*
1340          * "static" ccws are used in the following way:
1341          *
1342          * ccw[0..2] (Channel program for generic I/O):
1343          *           0: prepare
1344          *           1: read or write (depending on direction) with fixed
1345          *              buffer (idal allocated once when buffer is allocated)
1346          *           2: nop
1347          * ccw[3..5] (Channel program for direct write of packets)
1348          *           3: prepare
1349          *           4: write (idal allocated on every write).
1350          *           5: nop
1351          * ccw[6..7] (Channel program for initial channel setup):
1352          *           6: set extended mode
1353          *           7: nop
1354          *
1355          * ch->ccw[0..5] are initialized in ch_action_start because
1356          * the channel's direction is yet unknown here.
1357          *
1358          * ccws used for xid2 negotiations
1359          *  ch-ccw[8-14] need to be used for the XID exchange either
1360          *    X side XID2 Processing
1361          *       8:  write control
1362          *       9:  write th
1363          *           10: write XID
1364          *           11: read th from secondary
1365          *           12: read XID   from secondary
1366          *           13: read 4 byte ID
1367          *           14: nop
1368          *    Y side XID Processing
1369          *           8:  sense
1370          *       9:  read th
1371          *           10: read XID
1372          *           11: write th
1373          *           12: write XID
1374          *           13: write 4 byte ID
1375          *           14: nop
1376          *
1377          *  ccws used for double noop due to VM timing issues
1378          *  which result in unrecoverable Busy on channel
1379          *       15: nop
1380          *       16: nop
1381          */
1382         ch->ccw[6].cmd_code     = CCW_CMD_SET_EXTENDED;
1383         ch->ccw[6].flags        = CCW_FLAG_SLI;
1384
1385         ch->ccw[7].cmd_code     = CCW_CMD_NOOP;
1386         ch->ccw[7].flags        = CCW_FLAG_SLI;
1387
1388         if (IS_MPC(priv)) {
1389                 ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1390                 ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1391                 ch->ccw[15].count    = TH_HEADER_LENGTH;
1392                 ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1393
1394                 ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1395                 ch->ccw[16].flags    = CCW_FLAG_SLI;
1396
1397                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1398                                 ctc_ch_event_names, CTC_MPC_NR_STATES,
1399                                 CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1400                                 mpc_ch_fsm_len, GFP_KERNEL);
1401         } else {
1402                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1403                                 ctc_ch_event_names, CTC_NR_STATES,
1404                                 CTC_NR_EVENTS, ch_fsm,
1405                                 ch_fsm_len, GFP_KERNEL);
1406         }
1407         if (ch->fsm == NULL)
1408                                 goto nomem_return;
1409
1410         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1411
1412         ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1413         if (ch->irb == NULL)
1414                                 goto nomem_return;
1415
1416         while (*c && ctcm_less_than((*c)->id, ch->id))
1417                 c = &(*c)->next;
1418
1419         if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1420                 CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1421                                 "%s (%s) already in list, using old entry",
1422                                 __func__, (*c)->id);
1423
1424                 goto free_return;
1425         }
1426
1427         spin_lock_init(&ch->collect_lock);
1428
1429         fsm_settimer(ch->fsm, &ch->timer);
1430         skb_queue_head_init(&ch->io_queue);
1431         skb_queue_head_init(&ch->collect_queue);
1432
1433         if (IS_MPC(priv)) {
1434                 fsm_settimer(ch->fsm, &ch->sweep_timer);
1435                 skb_queue_head_init(&ch->sweep_queue);
1436         }
1437         ch->next = *c;
1438         *c = ch;
1439         return 0;
1440
1441 nomem_return:
1442         rc = -ENOMEM;
1443
1444 free_return:    /* note that all channel pointers are 0 or valid */
1445         kfree(ch->ccw);
1446         kfree(ch->discontact_th);
1447         kfree_fsm(ch->fsm);
1448         kfree(ch->irb);
1449         kfree(ch);
1450         return rc;
1451 }
1452
1453 /*
1454  * Return type of a detected device.
1455  */
1456 static enum ctcm_channel_types get_channel_type(struct ccw_device_id *id)
1457 {
1458         enum ctcm_channel_types type;
1459         type = (enum ctcm_channel_types)id->driver_info;
1460
1461         if (type == ctcm_channel_type_ficon)
1462                 type = ctcm_channel_type_escon;
1463
1464         return type;
1465 }
1466
1467 /*
1468  *
1469  * Setup an interface.
1470  *
1471  *  cgdev       Device to be setup.
1472  *
1473  * returns 0 on success, !0 on failure.
1474  */
1475 static int ctcm_new_device(struct ccwgroup_device *cgdev)
1476 {
1477         char read_id[CTCM_ID_SIZE];
1478         char write_id[CTCM_ID_SIZE];
1479         int direction;
1480         enum ctcm_channel_types type;
1481         struct ctcm_priv *priv;
1482         struct net_device *dev;
1483         struct ccw_device *cdev0;
1484         struct ccw_device *cdev1;
1485         struct channel *readc;
1486         struct channel *writec;
1487         int ret;
1488         int result;
1489
1490         priv = dev_get_drvdata(&cgdev->dev);
1491         if (!priv) {
1492                 result = -ENODEV;
1493                 goto out_err_result;
1494         }
1495
1496         cdev0 = cgdev->cdev[0];
1497         cdev1 = cgdev->cdev[1];
1498
1499         type = get_channel_type(&cdev0->id);
1500
1501         scnprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1502         scnprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1503
1504         ret = add_channel(cdev0, type, priv);
1505         if (ret) {
1506                 result = ret;
1507                 goto out_err_result;
1508         }
1509         ret = add_channel(cdev1, type, priv);
1510         if (ret) {
1511                 result = ret;
1512                 goto out_remove_channel1;
1513         }
1514
1515         ret = ccw_device_set_online(cdev0);
1516         if (ret != 0) {
1517                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1518                         "%s(%s) set_online rc=%d",
1519                                 CTCM_FUNTAIL, read_id, ret);
1520                 result = -EIO;
1521                 goto out_remove_channel2;
1522         }
1523
1524         ret = ccw_device_set_online(cdev1);
1525         if (ret != 0) {
1526                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1527                         "%s(%s) set_online rc=%d",
1528                                 CTCM_FUNTAIL, write_id, ret);
1529
1530                 result = -EIO;
1531                 goto out_ccw1;
1532         }
1533
1534         dev = ctcm_init_netdevice(priv);
1535         if (dev == NULL) {
1536                 result = -ENODEV;
1537                 goto out_ccw2;
1538         }
1539
1540         for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1541                 priv->channel[direction] =
1542                         channel_get(type, direction == CTCM_READ ?
1543                                 read_id : write_id, direction);
1544                 if (priv->channel[direction] == NULL) {
1545                         if (direction == CTCM_WRITE)
1546                                 channel_free(priv->channel[CTCM_READ]);
1547                         result = -ENODEV;
1548                         goto out_dev;
1549                 }
1550                 priv->channel[direction]->netdev = dev;
1551                 priv->channel[direction]->protocol = priv->protocol;
1552                 priv->channel[direction]->max_bufsize = priv->buffer_size;
1553         }
1554         /* sysfs magic */
1555         SET_NETDEV_DEV(dev, &cgdev->dev);
1556
1557         if (register_netdev(dev)) {
1558                 result = -ENODEV;
1559                 goto out_dev;
1560         }
1561
1562         strscpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1563
1564         dev_info(&dev->dev,
1565                 "setup OK : r/w = %s/%s, protocol : %d\n",
1566                         priv->channel[CTCM_READ]->id,
1567                         priv->channel[CTCM_WRITE]->id, priv->protocol);
1568
1569         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1570                 "setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1571                         priv->channel[CTCM_READ]->id,
1572                         priv->channel[CTCM_WRITE]->id, priv->protocol);
1573
1574         return 0;
1575 out_dev:
1576         ctcm_free_netdevice(dev);
1577 out_ccw2:
1578         ccw_device_set_offline(cgdev->cdev[1]);
1579 out_ccw1:
1580         ccw_device_set_offline(cgdev->cdev[0]);
1581 out_remove_channel2:
1582         readc = channel_get(type, read_id, CTCM_READ);
1583         channel_remove(readc);
1584 out_remove_channel1:
1585         writec = channel_get(type, write_id, CTCM_WRITE);
1586         channel_remove(writec);
1587 out_err_result:
1588         return result;
1589 }
1590
1591 /*
1592  * Shutdown an interface.
1593  *
1594  *  cgdev       Device to be shut down.
1595  *
1596  * returns 0 on success, !0 on failure.
1597  */
1598 static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1599 {
1600         struct ctcm_priv *priv;
1601         struct net_device *dev;
1602
1603         priv = dev_get_drvdata(&cgdev->dev);
1604         if (!priv)
1605                 return -ENODEV;
1606
1607         if (priv->channel[CTCM_READ]) {
1608                 dev = priv->channel[CTCM_READ]->netdev;
1609                 CTCM_DBF_DEV(SETUP, dev, "");
1610                 /* Close the device */
1611                 ctcm_close(dev);
1612                 dev->flags &= ~IFF_RUNNING;
1613                 channel_free(priv->channel[CTCM_READ]);
1614         } else
1615                 dev = NULL;
1616
1617         if (priv->channel[CTCM_WRITE])
1618                 channel_free(priv->channel[CTCM_WRITE]);
1619
1620         if (dev) {
1621                 unregister_netdev(dev);
1622                 ctcm_free_netdevice(dev);
1623         }
1624
1625         if (priv->fsm)
1626                 kfree_fsm(priv->fsm);
1627
1628         ccw_device_set_offline(cgdev->cdev[1]);
1629         ccw_device_set_offline(cgdev->cdev[0]);
1630         channel_remove(priv->channel[CTCM_READ]);
1631         channel_remove(priv->channel[CTCM_WRITE]);
1632         priv->channel[CTCM_READ] = priv->channel[CTCM_WRITE] = NULL;
1633
1634         return 0;
1635
1636 }
1637
1638
1639 static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1640 {
1641         struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1642
1643         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1644                         "removing device %p, proto : %d",
1645                         cgdev, priv->protocol);
1646
1647         if (cgdev->state == CCWGROUP_ONLINE)
1648                 ctcm_shutdown_device(cgdev);
1649         dev_set_drvdata(&cgdev->dev, NULL);
1650         kfree(priv);
1651         put_device(&cgdev->dev);
1652 }
1653
1654 static struct ccw_device_id ctcm_ids[] = {
1655         {CCW_DEVICE(0x3088, 0x08), .driver_info = ctcm_channel_type_parallel},
1656         {CCW_DEVICE(0x3088, 0x1e), .driver_info = ctcm_channel_type_ficon},
1657         {CCW_DEVICE(0x3088, 0x1f), .driver_info = ctcm_channel_type_escon},
1658         {},
1659 };
1660 MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1661
1662 static struct ccw_driver ctcm_ccw_driver = {
1663         .driver = {
1664                 .owner  = THIS_MODULE,
1665                 .name   = "ctcm",
1666         },
1667         .ids    = ctcm_ids,
1668         .probe  = ccwgroup_probe_ccwdev,
1669         .remove = ccwgroup_remove_ccwdev,
1670         .int_class = IRQIO_CTC,
1671 };
1672
1673 static struct ccwgroup_driver ctcm_group_driver = {
1674         .driver = {
1675                 .owner  = THIS_MODULE,
1676                 .name   = CTC_DRIVER_NAME,
1677         },
1678         .ccw_driver  = &ctcm_ccw_driver,
1679         .setup       = ctcm_probe_device,
1680         .remove      = ctcm_remove_device,
1681         .set_online  = ctcm_new_device,
1682         .set_offline = ctcm_shutdown_device,
1683 };
1684
1685 static ssize_t group_store(struct device_driver *ddrv, const char *buf,
1686                            size_t count)
1687 {
1688         int err;
1689
1690         err = ccwgroup_create_dev(ctcm_root_dev, &ctcm_group_driver, 2, buf);
1691         return err ? err : count;
1692 }
1693 static DRIVER_ATTR_WO(group);
1694
1695 static struct attribute *ctcm_drv_attrs[] = {
1696         &driver_attr_group.attr,
1697         NULL,
1698 };
1699 static struct attribute_group ctcm_drv_attr_group = {
1700         .attrs = ctcm_drv_attrs,
1701 };
1702 static const struct attribute_group *ctcm_drv_attr_groups[] = {
1703         &ctcm_drv_attr_group,
1704         NULL,
1705 };
1706
1707 /*
1708  * Module related routines
1709  */
1710
1711 /*
1712  * Prepare to be unloaded. Free IRQ's and release all resources.
1713  * This is called just before this module is unloaded. It is
1714  * not called, if the usage count is !0, so we don't need to check
1715  * for that.
1716  */
1717 static void __exit ctcm_exit(void)
1718 {
1719         ccwgroup_driver_unregister(&ctcm_group_driver);
1720         ccw_driver_unregister(&ctcm_ccw_driver);
1721         root_device_unregister(ctcm_root_dev);
1722         ctcm_unregister_dbf_views();
1723         pr_info("CTCM driver unloaded\n");
1724 }
1725
1726 /*
1727  * Print Banner.
1728  */
1729 static void print_banner(void)
1730 {
1731         pr_info("CTCM driver initialized\n");
1732 }
1733
1734 /*
1735  * Initialize module.
1736  * This is called just after the module is loaded.
1737  *
1738  * returns 0 on success, !0 on error.
1739  */
1740 static int __init ctcm_init(void)
1741 {
1742         int ret;
1743
1744         channels = NULL;
1745
1746         ret = ctcm_register_dbf_views();
1747         if (ret)
1748                 goto out_err;
1749         ctcm_root_dev = root_device_register("ctcm");
1750         ret = PTR_ERR_OR_ZERO(ctcm_root_dev);
1751         if (ret)
1752                 goto register_err;
1753         ret = ccw_driver_register(&ctcm_ccw_driver);
1754         if (ret)
1755                 goto ccw_err;
1756         ctcm_group_driver.driver.groups = ctcm_drv_attr_groups;
1757         ret = ccwgroup_driver_register(&ctcm_group_driver);
1758         if (ret)
1759                 goto ccwgroup_err;
1760         print_banner();
1761         return 0;
1762
1763 ccwgroup_err:
1764         ccw_driver_unregister(&ctcm_ccw_driver);
1765 ccw_err:
1766         root_device_unregister(ctcm_root_dev);
1767 register_err:
1768         ctcm_unregister_dbf_views();
1769 out_err:
1770         pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1771                 __func__, ret);
1772         return ret;
1773 }
1774
1775 module_init(ctcm_init);
1776 module_exit(ctcm_exit);
1777
1778 MODULE_AUTHOR("Peter Tiedemann <[email protected]>");
1779 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1780 MODULE_LICENSE("GPL");
1781