drivers/s390/net/ctcmain.c

   1 /*
   2  * CTC / ESCON network driver
   3  *
   4  * Copyright (C) 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation
   5  * Author(s): Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
   6  * Fixes by : Jochen Röhrig (roehrig@de.ibm.com)
   7  *            Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   8               Peter Tiedemann (ptiedem@de.ibm.com)
   9  * Driver Model stuff by : Cornelia Huck <huckc@de.ibm.com>
  10  *
  11  * Documentation used:
  12  *  - Principles of Operation (IBM doc#: SA22-7201-06)
  13  *  - Common IO/-Device Commands and Self Description (IBM doc#: SA22-7204-02)
  14  *  - Common IO/-Device Commands and Self Description (IBM doc#: SN22-5535)
  15  *  - ESCON Channel-to-Channel Adapter (IBM doc#: SA22-7203-00)
  16  *  - ESCON I/O Interface (IBM doc#: SA22-7202-029
  17  *
  18  * and the source of the original CTC driver by:
  19  *  Dieter Wellerdiek (wel@de.ibm.com)
  20  *  Martin Schwidefsky (schwidefsky@de.ibm.com)
  21  *  Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
  22  *  Jochen Röhrig (roehrig@de.ibm.com)
  23  *
  24  * This program is free software; you can redistribute it and/or modify
  25  * it under the terms of the GNU General Public License as published by
  26  * the Free Software Foundation; either version 2, or (at your option)
  27  * any later version.
  28  *
  29  * This program is distributed in the hope that it will be useful,
  30  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  31  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  32  * GNU General Public License for more details.
  33  *
  34  * You should have received a copy of the GNU General Public License
  35  * along with this program; if not, write to the Free Software
  36  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  37  *
  38  */
  39 #undef DEBUG
  40 #include <linux/module.h>
  41 #include <linux/init.h>
  42 #include <linux/kernel.h>
  43 #include <linux/slab.h>
  44 #include <linux/errno.h>
  45 #include <linux/types.h>
  46 #include <linux/interrupt.h>
  47 #include <linux/timer.h>
  48 #include <linux/sched.h>
  49 #include <linux/bitops.h>
  50
  51 #include <linux/signal.h>
  52 #include <linux/string.h>
  53
  54 #include <linux/ip.h>
  55 #include <linux/if_arp.h>
  56 #include <linux/tcp.h>
  57 #include <linux/skbuff.h>
  58 #include <linux/ctype.h>
  59 #include <net/dst.h>
  60
  61 #include <asm/io.h>
  62 #include <asm/ccwdev.h>
  63 #include <asm/ccwgroup.h>
  64 #include <asm/uaccess.h>
  65
  66 #include <asm/idals.h>
  67
  68 #include "ctctty.h"
  69 #include "fsm.h"
  70 #include "cu3088.h"
  71
  72 #include "ctcdbug.h"
  73 #include "ctcmain.h"
  74
  75 MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
  76 MODULE_DESCRIPTION("Linux for S/390 CTC/Escon Driver");
  77 MODULE_LICENSE("GPL");
  78 /**
  79  * States of the interface statemachine.
  80  */
  81 enum dev_states {
  82         DEV_STATE_STOPPED,
  83         DEV_STATE_STARTWAIT_RXTX,
  84         DEV_STATE_STARTWAIT_RX,
  85         DEV_STATE_STARTWAIT_TX,
  86         DEV_STATE_STOPWAIT_RXTX,
  87         DEV_STATE_STOPWAIT_RX,
  88         DEV_STATE_STOPWAIT_TX,
  89         DEV_STATE_RUNNING,
  90         /**
  91          * MUST be always the last element!!
  92          */
  93         CTC_NR_DEV_STATES
  94 };
  95
  96 static const char *dev_state_names[] = {
  97         "Stopped",
  98         "StartWait RXTX",
  99         "StartWait RX",
 100         "StartWait TX",
 101         "StopWait RXTX",
 102         "StopWait RX",
 103         "StopWait TX",
 104         "Running",
 105 };
 106
 107 /**
 108  * Events of the interface statemachine.
 109  */
 110 enum dev_events {
 111         DEV_EVENT_START,
 112         DEV_EVENT_STOP,
 113         DEV_EVENT_RXUP,
 114         DEV_EVENT_TXUP,
 115         DEV_EVENT_RXDOWN,
 116         DEV_EVENT_TXDOWN,
 117         DEV_EVENT_RESTART,
 118         /**
 119          * MUST be always the last element!!
 120          */
 121         CTC_NR_DEV_EVENTS
 122 };
 123
 124 static const char *dev_event_names[] = {
 125         "Start",
 126         "Stop",
 127         "RX up",
 128         "TX up",
 129         "RX down",
 130         "TX down",
 131         "Restart",
 132 };
 133
 134 /**
 135  * Events of the channel statemachine
 136  */
 137 enum ch_events {
 138         /**
 139          * Events, representing return code of
 140          * I/O operations (ccw_device_start, ccw_device_halt et al.)
 141          */
 142         CH_EVENT_IO_SUCCESS,
 143         CH_EVENT_IO_EBUSY,
 144         CH_EVENT_IO_ENODEV,
 145         CH_EVENT_IO_EIO,
 146         CH_EVENT_IO_UNKNOWN,
 147
 148         CH_EVENT_ATTNBUSY,
 149         CH_EVENT_ATTN,
 150         CH_EVENT_BUSY,
 151
 152         /**
 153          * Events, representing unit-check
 154          */
 155         CH_EVENT_UC_RCRESET,
 156         CH_EVENT_UC_RSRESET,
 157         CH_EVENT_UC_TXTIMEOUT,
 158         CH_EVENT_UC_TXPARITY,
 159         CH_EVENT_UC_HWFAIL,
 160         CH_EVENT_UC_RXPARITY,
 161         CH_EVENT_UC_ZERO,
 162         CH_EVENT_UC_UNKNOWN,
 163
 164         /**
 165          * Events, representing subchannel-check
 166          */
 167         CH_EVENT_SC_UNKNOWN,
 168
 169         /**
 170          * Events, representing machine checks
 171          */
 172         CH_EVENT_MC_FAIL,
 173         CH_EVENT_MC_GOOD,
 174
 175         /**
 176          * Event, representing normal IRQ
 177          */
 178         CH_EVENT_IRQ,
 179         CH_EVENT_FINSTAT,
 180
 181         /**
 182          * Event, representing timer expiry.
 183          */
 184         CH_EVENT_TIMER,
 185
 186         /**
 187          * Events, representing commands from upper levels.
 188          */
 189         CH_EVENT_START,
 190         CH_EVENT_STOP,
 191
 192         /**
 193          * MUST be always the last element!!
 194          */
 195         NR_CH_EVENTS,
 196 };
 197
 198 /**
 199  * States of the channel statemachine.
 200  */
 201 enum ch_states {
 202         /**
 203          * Channel not assigned to any device,
 204          * initial state, direction invalid
 205          */
 206         CH_STATE_IDLE,
 207
 208         /**
 209          * Channel assigned but not operating
 210          */
 211         CH_STATE_STOPPED,
 212         CH_STATE_STARTWAIT,
 213         CH_STATE_STARTRETRY,
 214         CH_STATE_SETUPWAIT,
 215         CH_STATE_RXINIT,
 216         CH_STATE_TXINIT,
 217         CH_STATE_RX,
 218         CH_STATE_TX,
 219         CH_STATE_RXIDLE,
 220         CH_STATE_TXIDLE,
 221         CH_STATE_RXERR,
 222         CH_STATE_TXERR,
 223         CH_STATE_TERM,
 224         CH_STATE_DTERM,
 225         CH_STATE_NOTOP,
 226
 227         /**
 228          * MUST be always the last element!!
 229          */
 230         NR_CH_STATES,
 231 };
 232
 233 static int loglevel = CTC_LOGLEVEL_DEFAULT;
 234
 235 /**
 236  * Linked list of all detected channels.
 237  */
 238 static struct channel *channels = NULL;
 239
 240 /**
 241  * Print Banner.
 242  */
 243 static void
 244 print_banner(void)
 245 {
 246         static int printed = 0;
 247
 248         if (printed)
 249                 return;
 250
 251         printk(KERN_INFO "CTC driver initialized\n");
 252         printed = 1;
 253 }
 254
 255 /**
 256  * Return type of a detected device.
 257  */
 258 static enum channel_types
 259 get_channel_type(struct ccw_device_id *id)
 260 {
 261         enum channel_types type = (enum channel_types) id->driver_info;
 262
 263         if (type == channel_type_ficon)
 264                 type = channel_type_escon;
 265
 266         return type;
 267 }
 268
 269 static const char *ch_event_names[] = {
 270         "ccw_device success",
 271         "ccw_device busy",
 272         "ccw_device enodev",
 273         "ccw_device ioerr",
 274         "ccw_device unknown",
 275
 276         "Status ATTN & BUSY",
 277         "Status ATTN",
 278         "Status BUSY",
 279
 280         "Unit check remote reset",
 281         "Unit check remote system reset",
 282         "Unit check TX timeout",
 283         "Unit check TX parity",
 284         "Unit check Hardware failure",
 285         "Unit check RX parity",
 286         "Unit check ZERO",
 287         "Unit check Unknown",
 288
 289         "SubChannel check Unknown",
 290
 291         "Machine check failure",
 292         "Machine check operational",
 293
 294         "IRQ normal",
 295         "IRQ final",
 296
 297         "Timer",
 298
 299         "Start",
 300         "Stop",
 301 };
 302
 303 static const char *ch_state_names[] = {
 304         "Idle",
 305         "Stopped",
 306         "StartWait",
 307         "StartRetry",
 308         "SetupWait",
 309         "RX init",
 310         "TX init",
 311         "RX",
 312         "TX",
 313         "RX idle",
 314         "TX idle",
 315         "RX error",
 316         "TX error",
 317         "Terminating",
 318         "Restarting",
 319         "Not operational",
 320 };
 321
 322 #ifdef DEBUG
 323 /**
 324  * Dump header and first 16 bytes of an sk_buff for debugging purposes.
 325  *
 326  * @param skb    The sk_buff to dump.
 327  * @param offset Offset relative to skb-data, where to start the dump.
 328  */
 329 static void
 330 ctc_dump_skb(struct sk_buff *skb, int offset)
 331 {
 332         unsigned char *p = skb->data;
 333         __u16 bl;
 334         struct ll_header *header;
 335         int i;
 336
 337         if (!(loglevel & CTC_LOGLEVEL_DEBUG))
 338                 return;
 339         p += offset;
 340         bl = *((__u16 *) p);
 341         p += 2;
 342         header = (struct ll_header *) p;
 343         p -= 2;
 344
 345         printk(KERN_DEBUG "dump:\n");
 346         printk(KERN_DEBUG "blocklen=%d %04x\n", bl, bl);
 347
 348         printk(KERN_DEBUG "h->length=%d %04x\n", header->length,
 349                header->length);
 350         printk(KERN_DEBUG "h->type=%04x\n", header->type);
 351         printk(KERN_DEBUG "h->unused=%04x\n", header->unused);
 352         if (bl > 16)
 353                 bl = 16;
 354         printk(KERN_DEBUG "data: ");
 355         for (i = 0; i < bl; i++)
 356                 printk("%02x%s", *p++, (i % 16) ? " " : "\n<7>");
 357         printk("\n");
 358 }
 359 #else
 360 static inline void
 361 ctc_dump_skb(struct sk_buff *skb, int offset)
 362 {
 363 }
 364 #endif
 365
 366 /**
 367  * Unpack a just received skb and hand it over to
 368  * upper layers.
 369  *
 370  * @param ch The channel where this skb has been received.
 371  * @param pskb The received skb.
 372  */
 373 static __inline__ void
 374 ctc_unpack_skb(struct channel *ch, struct sk_buff *pskb)
 375 {
 376         struct net_device *dev = ch->netdev;
 377         struct ctc_priv *privptr = (struct ctc_priv *) dev->priv;
 378         __u16 len = *((__u16 *) pskb->data);
 379
 380         DBF_TEXT(trace, 4, __FUNCTION__);
 381         skb_put(pskb, 2 + LL_HEADER_LENGTH);
 382         skb_pull(pskb, 2);
 383         pskb->dev = dev;
 384         pskb->ip_summed = CHECKSUM_UNNECESSARY;
 385         while (len > 0) {
 386                 struct sk_buff *skb;
 387                 struct ll_header *header = (struct ll_header *) pskb->data;
 388
 389                 skb_pull(pskb, LL_HEADER_LENGTH);
 390                 if ((ch->protocol == CTC_PROTO_S390) &&
 391                     (header->type != ETH_P_IP)) {
 392
 393 #ifndef DEBUG
 394                         if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
 395 #endif
 396                                 /**
 397                                  * Check packet type only if we stick strictly
 398                                  * to S/390's protocol of OS390. This only
 399                                  * supports IP. Otherwise allow any packet
 400                                  * type.
 401                                  */
 402                                 ctc_pr_warn(
 403                                         "%s Illegal packet type 0x%04x received, dropping\n",
 404                                         dev->name, header->type);
 405                                 ch->logflags |= LOG_FLAG_ILLEGALPKT;
 406 #ifndef DEBUG
 407                         }
 408 #endif
 409 #ifdef DEBUG
 410                         ctc_dump_skb(pskb, -6);
 411 #endif
 412                         privptr->stats.rx_dropped++;
 413                         privptr->stats.rx_frame_errors++;
 414                         return;
 415                 }
 416                 pskb->protocol = ntohs(header->type);
 417                 if (header->length <= LL_HEADER_LENGTH) {
 418 #ifndef DEBUG
 419                         if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
 420 #endif
 421                                 ctc_pr_warn(
 422                                        "%s Illegal packet size %d "
 423                                        "received (MTU=%d blocklen=%d), "
 424                                        "dropping\n", dev->name, header->length,
 425                                        dev->mtu, len);
 426                                 ch->logflags |= LOG_FLAG_ILLEGALSIZE;
 427 #ifndef DEBUG
 428                         }
 429 #endif
 430 #ifdef DEBUG
 431                         ctc_dump_skb(pskb, -6);
 432 #endif
 433                         privptr->stats.rx_dropped++;
 434                         privptr->stats.rx_length_errors++;
 435                         return;
 436                 }
 437                 header->length -= LL_HEADER_LENGTH;
 438                 len -= LL_HEADER_LENGTH;
 439                 if ((header->length > skb_tailroom(pskb)) ||
 440                     (header->length > len)) {
 441 #ifndef DEBUG
 442                         if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 443 #endif
 444                                 ctc_pr_warn(
 445                                         "%s Illegal packet size %d "
 446                                         "(beyond the end of received data), "
 447                                         "dropping\n", dev->name, header->length);
 448                                 ch->logflags |= LOG_FLAG_OVERRUN;
 449 #ifndef DEBUG
 450                         }
 451 #endif
 452 #ifdef DEBUG
 453                         ctc_dump_skb(pskb, -6);
 454 #endif
 455                         privptr->stats.rx_dropped++;
 456                         privptr->stats.rx_length_errors++;
 457                         return;
 458                 }
 459                 skb_put(pskb, header->length);
 460                 pskb->mac.raw = pskb->data;
 461                 len -= header->length;
 462                 skb = dev_alloc_skb(pskb->len);
 463                 if (!skb) {
 464 #ifndef DEBUG
 465                         if (!(ch->logflags & LOG_FLAG_NOMEM)) {
 466 #endif
 467                                 ctc_pr_warn(
 468                                         "%s Out of memory in ctc_unpack_skb\n",
 469                                         dev->name);
 470                                 ch->logflags |= LOG_FLAG_NOMEM;
 471 #ifndef DEBUG
 472                         }
 473 #endif
 474                         privptr->stats.rx_dropped++;
 475                         return;
 476                 }
 477                 memcpy(skb_put(skb, pskb->len), pskb->data, pskb->len);
 478                 skb->mac.raw = skb->data;
 479                 skb->dev = pskb->dev;
 480                 skb->protocol = pskb->protocol;
 481                 pskb->ip_summed = CHECKSUM_UNNECESSARY;
 482                 if (ch->protocol == CTC_PROTO_LINUX_TTY)
 483                         ctc_tty_netif_rx(skb);
 484                 else
 485                         netif_rx_ni(skb);
 486                 /**
 487                  * Successful rx; reset logflags
 488                  */
 489                 ch->logflags = 0;
 490                 dev->last_rx = jiffies;
 491                 privptr->stats.rx_packets++;
 492                 privptr->stats.rx_bytes += skb->len;
 493                 if (len > 0) {
 494                         skb_pull(pskb, header->length);
 495                         if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
 496 #ifndef DEBUG
 497                                 if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 498 #endif
 499                                         ctc_pr_warn(
 500                                                 "%s Overrun in ctc_unpack_skb\n",
 501                                                 dev->name);
 502                                         ch->logflags |= LOG_FLAG_OVERRUN;
 503 #ifndef DEBUG
 504                                 }
 505 #endif
 506                                 return;
 507                         }
 508                         skb_put(pskb, LL_HEADER_LENGTH);
 509                 }
 510         }
 511 }
 512
 513 /**
 514  * Check return code of a preceeding ccw_device call, halt_IO etc...
 515  *
 516  * @param ch          The channel, the error belongs to.
 517  * @param return_code The error code to inspect.
 518  */
 519 static void inline
 520 ccw_check_return_code(struct channel *ch, int return_code, char *msg)
 521 {
 522         DBF_TEXT(trace, 5, __FUNCTION__);
 523         switch (return_code) {
 524                 case 0:
 525                         fsm_event(ch->fsm, CH_EVENT_IO_SUCCESS, ch);
 526                         break;
 527                 case -EBUSY:
 528                         ctc_pr_warn("%s (%s): Busy !\n", ch->id, msg);
 529                         fsm_event(ch->fsm, CH_EVENT_IO_EBUSY, ch);
 530                         break;
 531                 case -ENODEV:
 532                         ctc_pr_emerg("%s (%s): Invalid device called for IO\n",
 533                                      ch->id, msg);
 534                         fsm_event(ch->fsm, CH_EVENT_IO_ENODEV, ch);
 535                         break;
 536                 case -EIO:
 537                         ctc_pr_emerg("%s (%s): Status pending... \n",
 538                                      ch->id, msg);
 539                         fsm_event(ch->fsm, CH_EVENT_IO_EIO, ch);
 540                         break;
 541                 default:
 542                         ctc_pr_emerg("%s (%s): Unknown error in do_IO %04x\n",
 543                                      ch->id, msg, return_code);
 544                         fsm_event(ch->fsm, CH_EVENT_IO_UNKNOWN, ch);
 545         }
 546 }
 547
 548 /**
 549  * Check sense of a unit check.
 550  *
 551  * @param ch    The channel, the sense code belongs to.
 552  * @param sense The sense code to inspect.
 553  */
 554 static void inline
 555 ccw_unit_check(struct channel *ch, unsigned char sense)
 556 {
 557         DBF_TEXT(trace, 5, __FUNCTION__);
 558         if (sense & SNS0_INTERVENTION_REQ) {
 559                 if (sense & 0x01) {
 560                         if (ch->protocol != CTC_PROTO_LINUX_TTY)
 561                                 ctc_pr_debug("%s: Interface disc. or Sel. reset "
 562                                         "(remote)\n", ch->id);
 563                         fsm_event(ch->fsm, CH_EVENT_UC_RCRESET, ch);
 564                 } else {
 565                         ctc_pr_debug("%s: System reset (remote)\n", ch->id);
 566                         fsm_event(ch->fsm, CH_EVENT_UC_RSRESET, ch);
 567                 }
 568         } else if (sense & SNS0_EQUIPMENT_CHECK) {
 569                 if (sense & SNS0_BUS_OUT_CHECK) {
 570                         ctc_pr_warn("%s: Hardware malfunction (remote)\n",
 571                                     ch->id);
 572                         fsm_event(ch->fsm, CH_EVENT_UC_HWFAIL, ch);
 573                 } else {
 574                         ctc_pr_warn("%s: Read-data parity error (remote)\n",
 575                                     ch->id);
 576                         fsm_event(ch->fsm, CH_EVENT_UC_RXPARITY, ch);
 577                 }
 578         } else if (sense & SNS0_BUS_OUT_CHECK) {
 579                 if (sense & 0x04) {
 580                         ctc_pr_warn("%s: Data-streaming timeout)\n", ch->id);
 581                         fsm_event(ch->fsm, CH_EVENT_UC_TXTIMEOUT, ch);
 582                 } else {
 583                         ctc_pr_warn("%s: Data-transfer parity error\n", ch->id);
 584                         fsm_event(ch->fsm, CH_EVENT_UC_TXPARITY, ch);
 585                 }
 586         } else if (sense & SNS0_CMD_REJECT) {
 587                 ctc_pr_warn("%s: Command reject\n", ch->id);
 588         } else if (sense == 0) {
 589                 ctc_pr_debug("%s: Unit check ZERO\n", ch->id);
 590                 fsm_event(ch->fsm, CH_EVENT_UC_ZERO, ch);
 591         } else {
 592                 ctc_pr_warn("%s: Unit Check with sense code: %02x\n",
 593                             ch->id, sense);
 594                 fsm_event(ch->fsm, CH_EVENT_UC_UNKNOWN, ch);
 595         }
 596 }
 597
 598 static void
 599 ctc_purge_skb_queue(struct sk_buff_head *q)
 600 {
 601         struct sk_buff *skb;
 602
 603         DBF_TEXT(trace, 5, __FUNCTION__);
 604
 605         while ((skb = skb_dequeue(q))) {
 606                 atomic_dec(&skb->users);
 607                 dev_kfree_skb_irq(skb);
 608         }
 609 }
 610
 611 static __inline__ int
 612 ctc_checkalloc_buffer(struct channel *ch, int warn)
 613 {
 614         DBF_TEXT(trace, 5, __FUNCTION__);
 615         if ((ch->trans_skb == NULL) ||
 616             (ch->flags & CHANNEL_FLAGS_BUFSIZE_CHANGED)) {
 617                 if (ch->trans_skb != NULL)
 618                         dev_kfree_skb(ch->trans_skb);
 619                 clear_normalized_cda(&ch->ccw[1]);
 620                 ch->trans_skb = __dev_alloc_skb(ch->max_bufsize,
 621                                                 GFP_ATOMIC | GFP_DMA);
 622                 if (ch->trans_skb == NULL) {
 623                         if (warn)
 624                                 ctc_pr_warn(
 625                                         "%s: Couldn't alloc %s trans_skb\n",
 626                                         ch->id,
 627                                         (CHANNEL_DIRECTION(ch->flags) == READ) ?
 628                                         "RX" : "TX");
 629                         return -ENOMEM;
 630                 }
 631                 ch->ccw[1].count = ch->max_bufsize;
 632                 if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
 633                         dev_kfree_skb(ch->trans_skb);
 634                         ch->trans_skb = NULL;
 635                         if (warn)
 636                                 ctc_pr_warn(
 637                                         "%s: set_normalized_cda for %s "
 638                                         "trans_skb failed, dropping packets\n",
 639                                         ch->id,
 640                                         (CHANNEL_DIRECTION(ch->flags) == READ) ?
 641                                         "RX" : "TX");
 642                         return -ENOMEM;
 643                 }
 644                 ch->ccw[1].count = 0;
 645                 ch->trans_skb_data = ch->trans_skb->data;
 646                 ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
 647         }
 648         return 0;
 649 }
 650
 651 /**
 652  * Dummy NOP action for statemachines
 653  */
 654 static void
 655 fsm_action_nop(fsm_instance * fi, int event, void *arg)
 656 {
 657 }
 658
 659 /**
 660  * Actions for channel - statemachines.
 661  *****************************************************************************/
 662
 663 /**
 664  * Normal data has been send. Free the corresponding
 665  * skb (it's in io_queue), reset dev->tbusy and
 666  * revert to idle state.
 667  *
 668  * @param fi    An instance of a channel statemachine.
 669  * @param event The event, just happened.
 670  * @param arg   Generic pointer, casted from channel * upon call.
 671  */
 672 static void
 673 ch_action_txdone(fsm_instance * fi, int event, void *arg)
 674 {
 675         struct channel *ch = (struct channel *) arg;
 676         struct net_device *dev = ch->netdev;
 677         struct ctc_priv *privptr = dev->priv;
 678         struct sk_buff *skb;
 679         int first = 1;
 680         int i;
 681         unsigned long duration;
 682         struct timespec done_stamp = xtime;
 683
 684         DBF_TEXT(trace, 4, __FUNCTION__);
 685
 686         duration =
 687             (done_stamp.tv_sec - ch->prof.send_stamp.tv_sec) * 1000000 +
 688             (done_stamp.tv_nsec - ch->prof.send_stamp.tv_nsec) / 1000;
 689         if (duration > ch->prof.tx_time)
 690                 ch->prof.tx_time = duration;
 691
 692         if (ch->irb->scsw.count != 0)
 693                 ctc_pr_debug("%s: TX not complete, remaining %d bytes\n",
 694                              dev->name, ch->irb->scsw.count);
 695         fsm_deltimer(&ch->timer);
 696         while ((skb = skb_dequeue(&ch->io_queue))) {
 697                 privptr->stats.tx_packets++;
 698                 privptr->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 699                 if (first) {
 700                         privptr->stats.tx_bytes += 2;
 701                         first = 0;
 702                 }
 703                 atomic_dec(&skb->users);
 704                 dev_kfree_skb_irq(skb);
 705         }
 706         spin_lock(&ch->collect_lock);
 707         clear_normalized_cda(&ch->ccw[4]);
 708         if (ch->collect_len > 0) {
 709                 int rc;
 710
 711                 if (ctc_checkalloc_buffer(ch, 1)) {
 712                         spin_unlock(&ch->collect_lock);
 713                         return;
 714                 }
 715                 ch->trans_skb->tail = ch->trans_skb->data = ch->trans_skb_data;
 716                 ch->trans_skb->len = 0;
 717                 if (ch->prof.maxmulti < (ch->collect_len + 2))
 718                         ch->prof.maxmulti = ch->collect_len + 2;
 719                 if (ch->prof.maxcqueue < skb_queue_len(&ch->collect_queue))
 720                         ch->prof.maxcqueue = skb_queue_len(&ch->collect_queue);
 721                 *((__u16 *) skb_put(ch->trans_skb, 2)) = ch->collect_len + 2;
 722                 i = 0;
 723                 while ((skb = skb_dequeue(&ch->collect_queue))) {
 724                         memcpy(skb_put(ch->trans_skb, skb->len), skb->data,
 725                                skb->len);
 726                         privptr->stats.tx_packets++;
 727                         privptr->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 728                         atomic_dec(&skb->users);
 729                         dev_kfree_skb_irq(skb);
 730                         i++;
 731                 }
 732                 ch->collect_len = 0;
 733                 spin_unlock(&ch->collect_lock);
 734                 ch->ccw[1].count = ch->trans_skb->len;
 735                 fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
 736                 ch->prof.send_stamp = xtime;
 737                 rc = ccw_device_start(ch->cdev, &ch->ccw[0],
 738                                       (unsigned long) ch, 0xff, 0);
 739                 ch->prof.doios_multi++;
 740                 if (rc != 0) {
 741                         privptr->stats.tx_dropped += i;
 742                         privptr->stats.tx_errors += i;
 743                         fsm_deltimer(&ch->timer);
 744                         ccw_check_return_code(ch, rc, "chained TX");
 745                 }
 746         } else {
 747                 spin_unlock(&ch->collect_lock);
 748                 fsm_newstate(fi, CH_STATE_TXIDLE);
 749         }
 750         ctc_clear_busy(dev);
 751 }
 752
 753 /**
 754  * Initial data is sent.
 755  * Notify device statemachine that we are up and
 756  * running.
 757  *
 758  * @param fi    An instance of a channel statemachine.
 759  * @param event The event, just happened.
 760  * @param arg   Generic pointer, casted from channel * upon call.
 761  */
 762 static void
 763 ch_action_txidle(fsm_instance * fi, int event, void *arg)
 764 {
 765         struct channel *ch = (struct channel *) arg;
 766
 767         DBF_TEXT(trace, 4, __FUNCTION__);
 768         fsm_deltimer(&ch->timer);
 769         fsm_newstate(fi, CH_STATE_TXIDLE);
 770         fsm_event(((struct ctc_priv *) ch->netdev->priv)->fsm, DEV_EVENT_TXUP,
 771                   ch->netdev);
 772 }
 773
 774 /**
 775  * Got normal data, check for sanity, queue it up, allocate new buffer
 776  * trigger bottom half, and initiate next read.
 777  *
 778  * @param fi    An instance of a channel statemachine.
 779  * @param event The event, just happened.
 780  * @param arg   Generic pointer, casted from channel * upon call.
 781  */
 782 static void
 783 ch_action_rx(fsm_instance * fi, int event, void *arg)
 784 {
 785         struct channel *ch = (struct channel *) arg;
 786         struct net_device *dev = ch->netdev;
 787         struct ctc_priv *privptr = dev->priv;
 788         int len = ch->max_bufsize - ch->irb->scsw.count;
 789         struct sk_buff *skb = ch->trans_skb;
 790         __u16 block_len = *((__u16 *) skb->data);
 791         int check_len;
 792         int rc;
 793
 794         DBF_TEXT(trace, 4, __FUNCTION__);
 795         fsm_deltimer(&ch->timer);
 796         if (len < 8) {
 797                 ctc_pr_debug("%s: got packet with length %d < 8\n",
 798                              dev->name, len);
 799                 privptr->stats.rx_dropped++;
 800                 privptr->stats.rx_length_errors++;
 801                 goto again;
 802         }
 803         if (len > ch->max_bufsize) {
 804                 ctc_pr_debug("%s: got packet with length %d > %d\n",
 805                              dev->name, len, ch->max_bufsize);
 806                 privptr->stats.rx_dropped++;
 807                 privptr->stats.rx_length_errors++;
 808                 goto again;
 809         }
 810
 811         /**
 812          * VM TCP seems to have a bug sending 2 trailing bytes of garbage.
 813          */
 814         switch (ch->protocol) {
 815                 case CTC_PROTO_S390:
 816                 case CTC_PROTO_OS390:
 817                         check_len = block_len + 2;
 818                         break;
 819                 default:
 820                         check_len = block_len;
 821                         break;
 822         }
 823         if ((len < block_len) || (len > check_len)) {
 824                 ctc_pr_debug("%s: got block length %d != rx length %d\n",
 825                              dev->name, block_len, len);
 826 #ifdef DEBUG
 827                 ctc_dump_skb(skb, 0);
 828 #endif
 829                 *((__u16 *) skb->data) = len;
 830                 privptr->stats.rx_dropped++;
 831                 privptr->stats.rx_length_errors++;
 832                 goto again;
 833         }
 834         block_len -= 2;
 835         if (block_len > 0) {
 836                 *((__u16 *) skb->data) = block_len;
 837                 ctc_unpack_skb(ch, skb);
 838         }
 839  again:
 840         skb->data = skb->tail = ch->trans_skb_data;
 841         skb->len = 0;
 842         if (ctc_checkalloc_buffer(ch, 1))
 843                 return;
 844         ch->ccw[1].count = ch->max_bufsize;
 845         rc = ccw_device_start(ch->cdev, &ch->ccw[0], (unsigned long) ch, 0xff, 0);
 846         if (rc != 0)
 847                 ccw_check_return_code(ch, rc, "normal RX");
 848 }
 849
 850 static void ch_action_rxidle(fsm_instance * fi, int event, void *arg);
 851
 852 /**
 853  * Initialize connection by sending a __u16 of value 0.
 854  *
 855  * @param fi    An instance of a channel statemachine.
 856  * @param event The event, just happened.
 857  * @param arg   Generic pointer, casted from channel * upon call.
 858  */
 859 static void
 860 ch_action_firstio(fsm_instance * fi, int event, void *arg)
 861 {
 862         struct channel *ch = (struct channel *) arg;
 863         int rc;
 864
 865         DBF_TEXT(trace, 4, __FUNCTION__);
 866
 867         if (fsm_getstate(fi) == CH_STATE_TXIDLE)
 868                 ctc_pr_debug("%s: remote side issued READ?, init ...\n", ch->id);
 869         fsm_deltimer(&ch->timer);
 870         if (ctc_checkalloc_buffer(ch, 1))
 871                 return;
 872         if ((fsm_getstate(fi) == CH_STATE_SETUPWAIT) &&
 873             (ch->protocol == CTC_PROTO_OS390)) {
 874                 /* OS/390 resp. z/OS */
 875                 if (CHANNEL_DIRECTION(ch->flags) == READ) {
 876                         *((__u16 *) ch->trans_skb->data) = CTC_INITIAL_BLOCKLEN;
 877                         fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC,
 878                                      CH_EVENT_TIMER, ch);
 879                         ch_action_rxidle(fi, event, arg);
 880                 } else {
 881                         struct net_device *dev = ch->netdev;
 882                         fsm_newstate(fi, CH_STATE_TXIDLE);
 883                         fsm_event(((struct ctc_priv *) dev->priv)->fsm,
 884                                   DEV_EVENT_TXUP, dev);
 885                 }
 886                 return;
 887         }
 888
 889         /**
 890          * Don´t setup a timer for receiving the initial RX frame
 891          * if in compatibility mode, since VM TCP delays the initial
 892          * frame until it has some data to send.
 893          */
 894         if ((CHANNEL_DIRECTION(ch->flags) == WRITE) ||
 895             (ch->protocol != CTC_PROTO_S390))
 896                 fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
 897
 898         *((__u16 *) ch->trans_skb->data) = CTC_INITIAL_BLOCKLEN;
 899         ch->ccw[1].count = 2;   /* Transfer only length */
 900
 901         fsm_newstate(fi, (CHANNEL_DIRECTION(ch->flags) == READ)
 902                      ? CH_STATE_RXINIT : CH_STATE_TXINIT);
 903         rc = ccw_device_start(ch->cdev, &ch->ccw[0], (unsigned long) ch, 0xff, 0);
 904         if (rc != 0) {
 905                 fsm_deltimer(&ch->timer);
 906                 fsm_newstate(fi, CH_STATE_SETUPWAIT);
 907                 ccw_check_return_code(ch, rc, "init IO");
 908         }
 909         /**
 910          * If in compatibility mode since we don´t setup a timer, we
 911          * also signal RX channel up immediately. This enables us
 912          * to send packets early which in turn usually triggers some
 913          * reply from VM TCP which brings up the RX channel to it´s
 914          * final state.
 915          */
 916         if ((CHANNEL_DIRECTION(ch->flags) == READ) &&
 917             (ch->protocol == CTC_PROTO_S390)) {
 918                 struct net_device *dev = ch->netdev;
 919                 fsm_event(((struct ctc_priv *) dev->priv)->fsm, DEV_EVENT_RXUP,
 920                           dev);
 921         }
 922 }
 923
 924 /**
 925  * Got initial data, check it. If OK,
 926  * notify device statemachine that we are up and
 927  * running.
 928  *
 929  * @param fi    An instance of a channel statemachine.
 930  * @param event The event, just happened.
 931  * @param arg   Generic pointer, casted from channel * upon call.
 932  */
 933 static void
 934 ch_action_rxidle(fsm_instance * fi, int event, void *arg)
 935 {
 936         struct channel *ch = (struct channel *) arg;
 937         struct net_device *dev = ch->netdev;
 938         __u16 buflen;
 939         int rc;
 940
 941         DBF_TEXT(trace, 4, __FUNCTION__);
 942         fsm_deltimer(&ch->timer);
 943         buflen = *((__u16 *) ch->trans_skb->data);
 944 #ifdef DEBUG
 945         ctc_pr_debug("%s: Initial RX count %d\n", dev->name, buflen);
 946 #endif
 947         if (buflen >= CTC_INITIAL_BLOCKLEN) {
 948                 if (ctc_checkalloc_buffer(ch, 1))
 949                         return;
 950                 ch->ccw[1].count = ch->max_bufsize;
 951                 fsm_newstate(fi, CH_STATE_RXIDLE);
 952                 rc = ccw_device_start(ch->cdev, &ch->ccw[0],
 953                                       (unsigned long) ch, 0xff, 0);
 954                 if (rc != 0) {
 955                         fsm_newstate(fi, CH_STATE_RXINIT);
 956                         ccw_check_return_code(ch, rc, "initial RX");
 957                 } else
 958                         fsm_event(((struct ctc_priv *) dev->priv)->fsm,
 959                                   DEV_EVENT_RXUP, dev);
 960         } else {
 961                 ctc_pr_debug("%s: Initial RX count %d not %d\n",
 962                              dev->name, buflen, CTC_INITIAL_BLOCKLEN);
 963                 ch_action_firstio(fi, event, arg);
 964         }
 965 }
 966
 967 /**
 968  * Set channel into extended mode.
 969  *
 970  * @param fi    An instance of a channel statemachine.
 971  * @param event The event, just happened.
 972  * @param arg   Generic pointer, casted from channel * upon call.
 973  */
 974 static void
 975 ch_action_setmode(fsm_instance * fi, int event, void *arg)
 976 {
 977         struct channel *ch = (struct channel *) arg;
 978         int rc;
 979         unsigned long saveflags;
 980
 981         DBF_TEXT(trace, 4, __FUNCTION__);
 982         fsm_deltimer(&ch->timer);
 983         fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
 984         fsm_newstate(fi, CH_STATE_SETUPWAIT);
 985         saveflags = 0;  /* avoids compiler warning with
 986                            spin_unlock_irqrestore */
 987         if (event == CH_EVENT_TIMER)    // only for timer not yet locked
 988                 spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 989         rc = ccw_device_start(ch->cdev, &ch->ccw[6], (unsigned long) ch, 0xff, 0);
 990         if (event == CH_EVENT_TIMER)
 991                 spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 992         if (rc != 0) {
 993                 fsm_deltimer(&ch->timer);
 994                 fsm_newstate(fi, CH_STATE_STARTWAIT);
 995                 ccw_check_return_code(ch, rc, "set Mode");
 996         } else
 997                 ch->retry = 0;
 998 }
 999
1000 /**
1001  * Setup channel.
1002  *
1003  * @param fi    An instance of a channel statemachine.
1004  * @param event The event, just happened.
1005  * @param arg   Generic pointer, casted from channel * upon call.
1006  */
1007 static void
1008 ch_action_start(fsm_instance * fi, int event, void *arg)
1009 {
1010         struct channel *ch = (struct channel *) arg;
1011         unsigned long saveflags;
1012         int rc;
1013         struct net_device *dev;
1014
1015         DBF_TEXT(trace, 4, __FUNCTION__);
1016         if (ch == NULL) {
1017                 ctc_pr_warn("ch_action_start ch=NULL\n");
1018                 return;
1019         }
1020         if (ch->netdev == NULL) {
1021                 ctc_pr_warn("ch_action_start dev=NULL, id=%s\n", ch->id);
1022                 return;
1023         }
1024         dev = ch->netdev;
1025
1026 #ifdef DEBUG
1027         ctc_pr_debug("%s: %s channel start\n", dev->name,
1028                      (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
1029 #endif
1030
1031         if (ch->trans_skb != NULL) {
1032                 clear_normalized_cda(&ch->ccw[1]);
1033                 dev_kfree_skb(ch->trans_skb);
1034                 ch->trans_skb = NULL;
1035         }
1036         if (CHANNEL_DIRECTION(ch->flags) == READ) {
1037                 ch->ccw[1].cmd_code = CCW_CMD_READ;
1038                 ch->ccw[1].flags = CCW_FLAG_SLI;
1039                 ch->ccw[1].count = 0;
1040         } else {
1041                 ch->ccw[1].cmd_code = CCW_CMD_WRITE;
1042                 ch->ccw[1].flags = CCW_FLAG_SLI | CCW_FLAG_CC;
1043                 ch->ccw[1].count = 0;
1044         }
1045         if (ctc_checkalloc_buffer(ch, 0)) {
1046                 ctc_pr_notice(
1047                         "%s: Could not allocate %s trans_skb, delaying "
1048                         "allocation until first transfer\n",
1049                         dev->name,
1050                         (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
1051         }
1052
1053         ch->ccw[0].cmd_code = CCW_CMD_PREPARE;
1054         ch->ccw[0].flags = CCW_FLAG_SLI | CCW_FLAG_CC;
1055         ch->ccw[0].count = 0;
1056         ch->ccw[0].cda = 0;
1057         ch->ccw[2].cmd_code = CCW_CMD_NOOP;     /* jointed CE + DE */
1058         ch->ccw[2].flags = CCW_FLAG_SLI;
1059         ch->ccw[2].count = 0;
1060         ch->ccw[2].cda = 0;
1061         memcpy(&ch->ccw[3], &ch->ccw[0], sizeof (struct ccw1) * 3);
1062         ch->ccw[4].cda = 0;
1063         ch->ccw[4].flags &= ~CCW_FLAG_IDA;
1064
1065         fsm_newstate(fi, CH_STATE_STARTWAIT);
1066         fsm_addtimer(&ch->timer, 1000, CH_EVENT_TIMER, ch);
1067         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1068         rc = ccw_device_halt(ch->cdev, (unsigned long) ch);
1069         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1070         if (rc != 0) {
1071                 if (rc != -EBUSY)
1072                     fsm_deltimer(&ch->timer);
1073                 ccw_check_return_code(ch, rc, "initial HaltIO");
1074         }
1075 #ifdef DEBUG
1076         ctc_pr_debug("ctc: %s(): leaving\n", __func__);
1077 #endif
1078 }
1079
1080 /**
1081  * Shutdown a channel.
1082  *
1083  * @param fi    An instance of a channel statemachine.
1084  * @param event The event, just happened.
1085  * @param arg   Generic pointer, casted from channel * upon call.
1086  */
1087 static void
1088 ch_action_haltio(fsm_instance * fi, int event, void *arg)
1089 {
1090         struct channel *ch = (struct channel *) arg;
1091         unsigned long saveflags;
1092         int rc;
1093         int oldstate;
1094
1095         DBF_TEXT(trace, 3, __FUNCTION__);
1096         fsm_deltimer(&ch->timer);
1097         fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
1098         saveflags = 0;  /* avoids comp warning with
1099                            spin_unlock_irqrestore */
1100         if (event == CH_EVENT_STOP)     // only for STOP not yet locked
1101                 spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1102         oldstate = fsm_getstate(fi);
1103         fsm_newstate(fi, CH_STATE_TERM);
1104         rc = ccw_device_halt(ch->cdev, (unsigned long) ch);
1105         if (event == CH_EVENT_STOP)
1106                 spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1107         if (rc != 0) {
1108                 if (rc != -EBUSY) {
1109                     fsm_deltimer(&ch->timer);
1110                     fsm_newstate(fi, oldstate);
1111                 }
1112                 ccw_check_return_code(ch, rc, "HaltIO in ch_action_haltio");
1113         }
1114 }
1115
1116 /**
1117  * A channel has successfully been halted.
1118  * Cleanup it's queue and notify interface statemachine.
1119  *
1120  * @param fi    An instance of a channel statemachine.
1121  * @param event The event, just happened.
1122  * @param arg   Generic pointer, casted from channel * upon call.
1123  */
1124 static void
1125 ch_action_stopped(fsm_instance * fi, int event, void *arg)
1126 {
1127         struct channel *ch = (struct channel *) arg;
1128         struct net_device *dev = ch->netdev;
1129
1130         DBF_TEXT(trace, 3, __FUNCTION__);
1131         fsm_deltimer(&ch->timer);
1132         fsm_newstate(fi, CH_STATE_STOPPED);
1133         if (ch->trans_skb != NULL) {
1134                 clear_normalized_cda(&ch->ccw[1]);
1135                 dev_kfree_skb(ch->trans_skb);
1136                 ch->trans_skb = NULL;
1137         }
1138         if (CHANNEL_DIRECTION(ch->flags) == READ) {
1139                 skb_queue_purge(&ch->io_queue);
1140                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1141                           DEV_EVENT_RXDOWN, dev);
1142         } else {
1143                 ctc_purge_skb_queue(&ch->io_queue);
1144                 spin_lock(&ch->collect_lock);
1145                 ctc_purge_skb_queue(&ch->collect_queue);
1146                 ch->collect_len = 0;
1147                 spin_unlock(&ch->collect_lock);
1148                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1149                           DEV_EVENT_TXDOWN, dev);
1150         }
1151 }
1152
1153 /**
1154  * A stop command from device statemachine arrived and we are in
1155  * not operational mode. Set state to stopped.
1156  *
1157  * @param fi    An instance of a channel statemachine.
1158  * @param event The event, just happened.
1159  * @param arg   Generic pointer, casted from channel * upon call.
1160  */
1161 static void
1162 ch_action_stop(fsm_instance * fi, int event, void *arg)
1163 {
1164         fsm_newstate(fi, CH_STATE_STOPPED);
1165 }
1166
1167 /**
1168  * A machine check for no path, not operational status or gone device has
1169  * happened.
1170  * Cleanup queue and notify interface statemachine.
1171  *
1172  * @param fi    An instance of a channel statemachine.
1173  * @param event The event, just happened.
1174  * @param arg   Generic pointer, casted from channel * upon call.
1175  */
1176 static void
1177 ch_action_fail(fsm_instance * fi, int event, void *arg)
1178 {
1179         struct channel *ch = (struct channel *) arg;
1180         struct net_device *dev = ch->netdev;
1181
1182         DBF_TEXT(trace, 3, __FUNCTION__);
1183         fsm_deltimer(&ch->timer);
1184         fsm_newstate(fi, CH_STATE_NOTOP);
1185         if (CHANNEL_DIRECTION(ch->flags) == READ) {
1186                 skb_queue_purge(&ch->io_queue);
1187                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1188                           DEV_EVENT_RXDOWN, dev);
1189         } else {
1190                 ctc_purge_skb_queue(&ch->io_queue);
1191                 spin_lock(&ch->collect_lock);
1192                 ctc_purge_skb_queue(&ch->collect_queue);
1193                 ch->collect_len = 0;
1194                 spin_unlock(&ch->collect_lock);
1195                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1196                           DEV_EVENT_TXDOWN, dev);
1197         }
1198 }
1199
1200 /**
1201  * Handle error during setup of channel.
1202  *
1203  * @param fi    An instance of a channel statemachine.
1204  * @param event The event, just happened.
1205  * @param arg   Generic pointer, casted from channel * upon call.
1206  */
1207 static void
1208 ch_action_setuperr(fsm_instance * fi, int event, void *arg)
1209 {
1210         struct channel *ch = (struct channel *) arg;
1211         struct net_device *dev = ch->netdev;
1212
1213         DBF_TEXT(setup, 3, __FUNCTION__);
1214         /**
1215          * Special case: Got UC_RCRESET on setmode.
1216          * This means that remote side isn't setup. In this case
1217          * simply retry after some 10 secs...
1218          */
1219         if ((fsm_getstate(fi) == CH_STATE_SETUPWAIT) &&
1220             ((event == CH_EVENT_UC_RCRESET) ||
1221              (event == CH_EVENT_UC_RSRESET))) {
1222                 fsm_newstate(fi, CH_STATE_STARTRETRY);
1223                 fsm_deltimer(&ch->timer);
1224                 fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
1225                 if (CHANNEL_DIRECTION(ch->flags) == READ) {
1226                         int rc = ccw_device_halt(ch->cdev, (unsigned long) ch);
1227                         if (rc != 0)
1228                                 ccw_check_return_code(
1229                                         ch, rc, "HaltIO in ch_action_setuperr");
1230                 }
1231                 return;
1232         }
1233
1234         ctc_pr_debug("%s: Error %s during %s channel setup state=%s\n",
1235                      dev->name, ch_event_names[event],
1236                      (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX",
1237                      fsm_getstate_str(fi));
1238         if (CHANNEL_DIRECTION(ch->flags) == READ) {
1239                 fsm_newstate(fi, CH_STATE_RXERR);
1240                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1241                           DEV_EVENT_RXDOWN, dev);
1242         } else {
1243                 fsm_newstate(fi, CH_STATE_TXERR);
1244                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1245                           DEV_EVENT_TXDOWN, dev);
1246         }
1247 }
1248
1249 /**
1250  * Restart a channel after an error.
1251  *
1252  * @param fi    An instance of a channel statemachine.
1253  * @param event The event, just happened.
1254  * @param arg   Generic pointer, casted from channel * upon call.
1255  */
1256 static void
1257 ch_action_restart(fsm_instance * fi, int event, void *arg)
1258 {
1259         unsigned long saveflags;
1260         int oldstate;
1261         int rc;
1262
1263         struct channel *ch = (struct channel *) arg;
1264         struct net_device *dev = ch->netdev;
1265
1266         DBF_TEXT(trace, 3, __FUNCTION__);
1267         fsm_deltimer(&ch->timer);
1268         ctc_pr_debug("%s: %s channel restart\n", dev->name,
1269                      (CHANNEL_DIRECTION(ch->flags) == READ) ? "RX" : "TX");
1270         fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
1271         oldstate = fsm_getstate(fi);
1272         fsm_newstate(fi, CH_STATE_STARTWAIT);
1273         saveflags = 0;  /* avoids compiler warning with
1274                            spin_unlock_irqrestore */
1275         if (event == CH_EVENT_TIMER)    // only for timer not yet locked
1276                 spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1277         rc = ccw_device_halt(ch->cdev, (unsigned long) ch);
1278         if (event == CH_EVENT_TIMER)
1279                 spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1280         if (rc != 0) {
1281                 if (rc != -EBUSY) {
1282                     fsm_deltimer(&ch->timer);
1283                     fsm_newstate(fi, oldstate);
1284                 }
1285                 ccw_check_return_code(ch, rc, "HaltIO in ch_action_restart");
1286         }
1287 }
1288
1289 /**
1290  * Handle error during RX initial handshake (exchange of
1291  * 0-length block header)
1292  *
1293  * @param fi    An instance of a channel statemachine.
1294  * @param event The event, just happened.
1295  * @param arg   Generic pointer, casted from channel * upon call.
1296  */
1297 static void
1298 ch_action_rxiniterr(fsm_instance * fi, int event, void *arg)
1299 {
1300         struct channel *ch = (struct channel *) arg;
1301         struct net_device *dev = ch->netdev;
1302
1303         DBF_TEXT(setup, 3, __FUNCTION__);
1304         if (event == CH_EVENT_TIMER) {
1305                 fsm_deltimer(&ch->timer);
1306                 ctc_pr_debug("%s: Timeout during RX init handshake\n", dev->name);
1307                 if (ch->retry++ < 3)
1308                         ch_action_restart(fi, event, arg);
1309                 else {
1310                         fsm_newstate(fi, CH_STATE_RXERR);
1311                         fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1312                                   DEV_EVENT_RXDOWN, dev);
1313                 }
1314         } else
1315                 ctc_pr_warn("%s: Error during RX init handshake\n", dev->name);
1316 }
1317
1318 /**
1319  * Notify device statemachine if we gave up initialization
1320  * of RX channel.
1321  *
1322  * @param fi    An instance of a channel statemachine.
1323  * @param event The event, just happened.
1324  * @param arg   Generic pointer, casted from channel * upon call.
1325  */
1326 static void
1327 ch_action_rxinitfail(fsm_instance * fi, int event, void *arg)
1328 {
1329         struct channel *ch = (struct channel *) arg;
1330         struct net_device *dev = ch->netdev;
1331
1332         DBF_TEXT(setup, 3, __FUNCTION__);
1333         fsm_newstate(fi, CH_STATE_RXERR);
1334         ctc_pr_warn("%s: RX initialization failed\n", dev->name);
1335         ctc_pr_warn("%s: RX <-> RX connection detected\n", dev->name);
1336         fsm_event(((struct ctc_priv *) dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
1337 }
1338
1339 /**
1340  * Handle RX Unit check remote reset (remote disconnected)
1341  *
1342  * @param fi    An instance of a channel statemachine.
1343  * @param event The event, just happened.
1344  * @param arg   Generic pointer, casted from channel * upon call.
1345  */
1346 static void
1347 ch_action_rxdisc(fsm_instance * fi, int event, void *arg)
1348 {
1349         struct channel *ch = (struct channel *) arg;
1350         struct channel *ch2;
1351         struct net_device *dev = ch->netdev;
1352
1353         DBF_TEXT(trace, 3, __FUNCTION__);
1354         fsm_deltimer(&ch->timer);
1355         ctc_pr_debug("%s: Got remote disconnect, re-initializing ...\n",
1356                      dev->name);
1357
1358         /**
1359          * Notify device statemachine
1360          */
1361         fsm_event(((struct ctc_priv *) dev->priv)->fsm, DEV_EVENT_RXDOWN, dev);
1362         fsm_event(((struct ctc_priv *) dev->priv)->fsm, DEV_EVENT_TXDOWN, dev);
1363
1364         fsm_newstate(fi, CH_STATE_DTERM);
1365         ch2 = ((struct ctc_priv *) dev->priv)->channel[WRITE];
1366         fsm_newstate(ch2->fsm, CH_STATE_DTERM);
1367
1368         ccw_device_halt(ch->cdev, (unsigned long) ch);
1369         ccw_device_halt(ch2->cdev, (unsigned long) ch2);
1370 }
1371
1372 /**
1373  * Handle error during TX channel initialization.
1374  *
1375  * @param fi    An instance of a channel statemachine.
1376  * @param event The event, just happened.
1377  * @param arg   Generic pointer, casted from channel * upon call.
1378  */
1379 static void
1380 ch_action_txiniterr(fsm_instance * fi, int event, void *arg)
1381 {
1382         struct channel *ch = (struct channel *) arg;
1383         struct net_device *dev = ch->netdev;
1384
1385         DBF_TEXT(setup, 2, __FUNCTION__);
1386         if (event == CH_EVENT_TIMER) {
1387                 fsm_deltimer(&ch->timer);
1388                 ctc_pr_debug("%s: Timeout during TX init handshake\n", dev->name);
1389                 if (ch->retry++ < 3)
1390                         ch_action_restart(fi, event, arg);
1391                 else {
1392                         fsm_newstate(fi, CH_STATE_TXERR);
1393                         fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1394                                   DEV_EVENT_TXDOWN, dev);
1395                 }
1396         } else
1397                 ctc_pr_warn("%s: Error during TX init handshake\n", dev->name);
1398 }
1399
1400 /**
1401  * Handle TX timeout by retrying operation.
1402  *
1403  * @param fi    An instance of a channel statemachine.
1404  * @param event The event, just happened.
1405  * @param arg   Generic pointer, casted from channel * upon call.
1406  */
1407 static void
1408 ch_action_txretry(fsm_instance * fi, int event, void *arg)
1409 {
1410         struct channel *ch = (struct channel *) arg;
1411         struct net_device *dev = ch->netdev;
1412         unsigned long saveflags;
1413
1414         DBF_TEXT(trace, 4, __FUNCTION__);
1415         fsm_deltimer(&ch->timer);
1416         if (ch->retry++ > 3) {
1417                 ctc_pr_debug("%s: TX retry failed, restarting channel\n",
1418                              dev->name);
1419                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1420                           DEV_EVENT_TXDOWN, dev);
1421                 ch_action_restart(fi, event, arg);
1422         } else {
1423                 struct sk_buff *skb;
1424
1425                 ctc_pr_debug("%s: TX retry %d\n", dev->name, ch->retry);
1426                 if ((skb = skb_peek(&ch->io_queue))) {
1427                         int rc = 0;
1428
1429                         clear_normalized_cda(&ch->ccw[4]);
1430                         ch->ccw[4].count = skb->len;
1431                         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
1432                                 ctc_pr_debug(
1433                                         "%s: IDAL alloc failed, chan restart\n",
1434                                         dev->name);
1435                                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1436                                           DEV_EVENT_TXDOWN, dev);
1437                                 ch_action_restart(fi, event, arg);
1438                                 return;
1439                         }
1440                         fsm_addtimer(&ch->timer, 1000, CH_EVENT_TIMER, ch);
1441                         saveflags = 0;  /* avoids compiler warning with
1442                                            spin_unlock_irqrestore */
1443                         if (event == CH_EVENT_TIMER) // only for TIMER not yet locked
1444                                 spin_lock_irqsave(get_ccwdev_lock(ch->cdev),
1445                                                   saveflags);
1446                         rc = ccw_device_start(ch->cdev, &ch->ccw[3],
1447                                               (unsigned long) ch, 0xff, 0);
1448                         if (event == CH_EVENT_TIMER)
1449                                 spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev),
1450                                                        saveflags);
1451                         if (rc != 0) {
1452                                 fsm_deltimer(&ch->timer);
1453                                 ccw_check_return_code(ch, rc, "TX in ch_action_txretry");
1454                                 ctc_purge_skb_queue(&ch->io_queue);
1455                         }
1456                 }
1457         }
1458
1459 }
1460
1461 /**
1462  * Handle fatal errors during an I/O command.
1463  *
1464  * @param fi    An instance of a channel statemachine.
1465  * @param event The event, just happened.
1466  * @param arg   Generic pointer, casted from channel * upon call.
1467  */
1468 static void
1469 ch_action_iofatal(fsm_instance * fi, int event, void *arg)
1470 {
1471         struct channel *ch = (struct channel *) arg;
1472         struct net_device *dev = ch->netdev;
1473
1474         DBF_TEXT(trace, 3, __FUNCTION__);
1475         fsm_deltimer(&ch->timer);
1476         if (CHANNEL_DIRECTION(ch->flags) == READ) {
1477                 ctc_pr_debug("%s: RX I/O error\n", dev->name);
1478                 fsm_newstate(fi, CH_STATE_RXERR);
1479                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1480                           DEV_EVENT_RXDOWN, dev);
1481         } else {
1482                 ctc_pr_debug("%s: TX I/O error\n", dev->name);
1483                 fsm_newstate(fi, CH_STATE_TXERR);
1484                 fsm_event(((struct ctc_priv *) dev->priv)->fsm,
1485                           DEV_EVENT_TXDOWN, dev);
1486         }
1487 }
1488
1489 static void
1490 ch_action_reinit(fsm_instance *fi, int event, void *arg)
1491 {
1492         struct channel *ch = (struct channel *)arg;
1493         struct net_device *dev = ch->netdev;
1494         struct ctc_priv *privptr = dev->priv;
1495
1496         DBF_TEXT(trace, 4, __FUNCTION__);
1497         ch_action_iofatal(fi, event, arg);
1498         fsm_addtimer(&privptr->restart_timer, 1000, DEV_EVENT_RESTART, dev);
1499 }
1500
1501 /**
1502  * The statemachine for a channel.
1503  */
1504 static const fsm_node ch_fsm[] = {
1505         {CH_STATE_STOPPED,    CH_EVENT_STOP,       fsm_action_nop       },
1506         {CH_STATE_STOPPED,    CH_EVENT_START,      ch_action_start      },
1507         {CH_STATE_STOPPED,    CH_EVENT_FINSTAT,    fsm_action_nop       },
1508         {CH_STATE_STOPPED,    CH_EVENT_MC_FAIL,    fsm_action_nop       },
1509
1510         {CH_STATE_NOTOP,      CH_EVENT_STOP,       ch_action_stop       },
1511         {CH_STATE_NOTOP,      CH_EVENT_START,      fsm_action_nop       },
1512         {CH_STATE_NOTOP,      CH_EVENT_FINSTAT,    fsm_action_nop       },
1513         {CH_STATE_NOTOP,      CH_EVENT_MC_FAIL,    fsm_action_nop       },
1514         {CH_STATE_NOTOP,      CH_EVENT_MC_GOOD,    ch_action_start      },
1515
1516         {CH_STATE_STARTWAIT,  CH_EVENT_STOP,       ch_action_haltio     },
1517         {CH_STATE_STARTWAIT,  CH_EVENT_START,      fsm_action_nop       },
1518         {CH_STATE_STARTWAIT,  CH_EVENT_FINSTAT,    ch_action_setmode    },
1519         {CH_STATE_STARTWAIT,  CH_EVENT_TIMER,      ch_action_setuperr   },
1520         {CH_STATE_STARTWAIT,  CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1521         {CH_STATE_STARTWAIT,  CH_EVENT_IO_EIO,     ch_action_reinit     },
1522         {CH_STATE_STARTWAIT,  CH_EVENT_MC_FAIL,    ch_action_fail       },
1523
1524         {CH_STATE_STARTRETRY, CH_EVENT_STOP,       ch_action_haltio     },
1525         {CH_STATE_STARTRETRY, CH_EVENT_TIMER,      ch_action_setmode    },
1526         {CH_STATE_STARTRETRY, CH_EVENT_FINSTAT,    fsm_action_nop       },
1527         {CH_STATE_STARTRETRY, CH_EVENT_MC_FAIL,    ch_action_fail       },
1528
1529         {CH_STATE_SETUPWAIT,  CH_EVENT_STOP,       ch_action_haltio     },
1530         {CH_STATE_SETUPWAIT,  CH_EVENT_START,      fsm_action_nop       },
1531         {CH_STATE_SETUPWAIT,  CH_EVENT_FINSTAT,    ch_action_firstio    },
1532         {CH_STATE_SETUPWAIT,  CH_EVENT_UC_RCRESET, ch_action_setuperr   },
1533         {CH_STATE_SETUPWAIT,  CH_EVENT_UC_RSRESET, ch_action_setuperr   },
1534         {CH_STATE_SETUPWAIT,  CH_EVENT_TIMER,      ch_action_setmode    },
1535         {CH_STATE_SETUPWAIT,  CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1536         {CH_STATE_SETUPWAIT,  CH_EVENT_IO_EIO,     ch_action_reinit     },
1537         {CH_STATE_SETUPWAIT,  CH_EVENT_MC_FAIL,    ch_action_fail       },
1538
1539         {CH_STATE_RXINIT,     CH_EVENT_STOP,       ch_action_haltio     },
1540         {CH_STATE_RXINIT,     CH_EVENT_START,      fsm_action_nop       },
1541         {CH_STATE_RXINIT,     CH_EVENT_FINSTAT,    ch_action_rxidle     },
1542         {CH_STATE_RXINIT,     CH_EVENT_UC_RCRESET, ch_action_rxiniterr  },
1543         {CH_STATE_RXINIT,     CH_EVENT_UC_RSRESET, ch_action_rxiniterr  },
1544         {CH_STATE_RXINIT,     CH_EVENT_TIMER,      ch_action_rxiniterr  },
1545         {CH_STATE_RXINIT,     CH_EVENT_ATTNBUSY,   ch_action_rxinitfail },
1546         {CH_STATE_RXINIT,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1547         {CH_STATE_RXINIT,     CH_EVENT_IO_EIO,     ch_action_reinit     },
1548         {CH_STATE_RXINIT,     CH_EVENT_UC_ZERO,    ch_action_firstio    },
1549         {CH_STATE_RXINIT,     CH_EVENT_MC_FAIL,    ch_action_fail       },
1550
1551         {CH_STATE_RXIDLE,     CH_EVENT_STOP,       ch_action_haltio     },
1552         {CH_STATE_RXIDLE,     CH_EVENT_START,      fsm_action_nop       },
1553         {CH_STATE_RXIDLE,     CH_EVENT_FINSTAT,    ch_action_rx         },
1554         {CH_STATE_RXIDLE,     CH_EVENT_UC_RCRESET, ch_action_rxdisc     },
1555 //      {CH_STATE_RXIDLE,     CH_EVENT_UC_RSRESET, ch_action_rxretry    },
1556         {CH_STATE_RXIDLE,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1557         {CH_STATE_RXIDLE,     CH_EVENT_IO_EIO,     ch_action_reinit     },
1558         {CH_STATE_RXIDLE,     CH_EVENT_MC_FAIL,    ch_action_fail       },
1559         {CH_STATE_RXIDLE,     CH_EVENT_UC_ZERO,    ch_action_rx         },
1560
1561         {CH_STATE_TXINIT,     CH_EVENT_STOP,       ch_action_haltio     },
1562         {CH_STATE_TXINIT,     CH_EVENT_START,      fsm_action_nop       },
1563         {CH_STATE_TXINIT,     CH_EVENT_FINSTAT,    ch_action_txidle     },
1564         {CH_STATE_TXINIT,     CH_EVENT_UC_RCRESET, ch_action_txiniterr  },
1565         {CH_STATE_TXINIT,     CH_EVENT_UC_RSRESET, ch_action_txiniterr  },
1566         {CH_STATE_TXINIT,     CH_EVENT_TIMER,      ch_action_txiniterr  },
1567         {CH_STATE_TXINIT,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1568         {CH_STATE_TXINIT,     CH_EVENT_IO_EIO,     ch_action_reinit     },
1569         {CH_STATE_TXINIT,     CH_EVENT_MC_FAIL,    ch_action_fail       },
1570
1571         {CH_STATE_TXIDLE,     CH_EVENT_STOP,       ch_action_haltio     },
1572         {CH_STATE_TXIDLE,     CH_EVENT_START,      fsm_action_nop       },
1573         {CH_STATE_TXIDLE,     CH_EVENT_FINSTAT,    ch_action_firstio    },
1574         {CH_STATE_TXIDLE,     CH_EVENT_UC_RCRESET, fsm_action_nop       },
1575         {CH_STATE_TXIDLE,     CH_EVENT_UC_RSRESET, fsm_action_nop       },
1576         {CH_STATE_TXIDLE,     CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1577         {CH_STATE_TXIDLE,     CH_EVENT_IO_EIO,     ch_action_reinit     },
1578         {CH_STATE_TXIDLE,     CH_EVENT_MC_FAIL,    ch_action_fail       },
1579
1580         {CH_STATE_TERM,       CH_EVENT_STOP,       fsm_action_nop       },
1581         {CH_STATE_TERM,       CH_EVENT_START,      ch_action_restart    },
1582         {CH_STATE_TERM,       CH_EVENT_FINSTAT,    ch_action_stopped    },
1583         {CH_STATE_TERM,       CH_EVENT_UC_RCRESET, fsm_action_nop       },
1584         {CH_STATE_TERM,       CH_EVENT_UC_RSRESET, fsm_action_nop       },
1585         {CH_STATE_TERM,       CH_EVENT_MC_FAIL,    ch_action_fail       },
1586
1587         {CH_STATE_DTERM,      CH_EVENT_STOP,       ch_action_haltio     },
1588         {CH_STATE_DTERM,      CH_EVENT_START,      ch_action_restart    },
1589         {CH_STATE_DTERM,      CH_EVENT_FINSTAT,    ch_action_setmode    },
1590         {CH_STATE_DTERM,      CH_EVENT_UC_RCRESET, fsm_action_nop       },
1591         {CH_STATE_DTERM,      CH_EVENT_UC_RSRESET, fsm_action_nop       },
1592         {CH_STATE_DTERM,      CH_EVENT_MC_FAIL,    ch_action_fail       },
1593
1594         {CH_STATE_TX,         CH_EVENT_STOP,       ch_action_haltio     },
1595         {CH_STATE_TX,         CH_EVENT_START,      fsm_action_nop       },
1596         {CH_STATE_TX,         CH_EVENT_FINSTAT,    ch_action_txdone     },
1597         {CH_STATE_TX,         CH_EVENT_UC_RCRESET, ch_action_txretry    },
1598         {CH_STATE_TX,         CH_EVENT_UC_RSRESET, ch_action_txretry    },
1599         {CH_STATE_TX,         CH_EVENT_TIMER,      ch_action_txretry    },
1600         {CH_STATE_TX,         CH_EVENT_IO_ENODEV,  ch_action_iofatal    },
1601         {CH_STATE_TX,         CH_EVENT_IO_EIO,     ch_action_reinit     },
1602         {CH_STATE_TX,         CH_EVENT_MC_FAIL,    ch_action_fail       },
1603
1604         {CH_STATE_RXERR,      CH_EVENT_STOP,       ch_action_haltio     },
1605         {CH_STATE_TXERR,      CH_EVENT_STOP,       ch_action_haltio     },
1606         {CH_STATE_TXERR,      CH_EVENT_MC_FAIL,    ch_action_fail       },
1607         {CH_STATE_RXERR,      CH_EVENT_MC_FAIL,    ch_action_fail       },
1608 };
1609
1610 static const int CH_FSM_LEN = sizeof (ch_fsm) / sizeof (fsm_node);
1611
1612 /**
1613  * Functions related to setup and device detection.
1614  *****************************************************************************/
1615
1616 static inline int
1617 less_than(char *id1, char *id2)
1618 {
1619         int dev1, dev2, i;
1620
1621         for (i = 0; i < 5; i++) {
1622                 id1++;
1623                 id2++;
1624         }
1625         dev1 = simple_strtoul(id1, &id1, 16);
1626         dev2 = simple_strtoul(id2, &id2, 16);
1627
1628         return (dev1 < dev2);
1629 }
1630
1631 /**
1632  * Add a new channel to the list of channels.
1633  * Keeps the channel list sorted.
1634  *
1635  * @param cdev  The ccw_device to be added.
1636  * @param type  The type class of the new channel.
1637  *
1638  * @return 0 on success, !0 on error.
1639  */
1640 static int
1641 add_channel(struct ccw_device *cdev, enum channel_types type)
1642 {
1643         struct channel **c = &channels;
1644         struct channel *ch;
1645
1646         DBF_TEXT(trace, 2, __FUNCTION__);
1647         if ((ch =
1648              (struct channel *) kmalloc(sizeof (struct channel),
1649                                         GFP_KERNEL)) == NULL) {
1650                 ctc_pr_warn("ctc: Out of memory in add_channel\n");
1651                 return -1;
1652         }
1653         memset(ch, 0, sizeof (struct channel));
1654         if ((ch->ccw = (struct ccw1 *) kmalloc(8*sizeof(struct ccw1),
1655                                                GFP_KERNEL | GFP_DMA)) == NULL) {
1656                 kfree(ch);
1657                 ctc_pr_warn("ctc: Out of memory in add_channel\n");
1658                 return -1;
1659         }
1660
1661         memset(ch->ccw, 0, 8*sizeof(struct ccw1));      // assure all flags and counters are reset
1662
1663         /**
1664          * "static" ccws are used in the following way:
1665          *
1666          * ccw[0..2] (Channel program for generic I/O):
1667          *           0: prepare
1668          *           1: read or write (depending on direction) with fixed
1669          *              buffer (idal allocated once when buffer is allocated)
1670          *           2: nop
1671          * ccw[3..5] (Channel program for direct write of packets)
1672          *           3: prepare
1673          *           4: write (idal allocated on every write).
1674          *           5: nop
1675          * ccw[6..7] (Channel program for initial channel setup):
1676          *           6: set extended mode
1677          *           7: nop
1678          *
1679          * ch->ccw[0..5] are initialized in ch_action_start because
1680          * the channel's direction is yet unknown here.
1681          */
1682         ch->ccw[6].cmd_code = CCW_CMD_SET_EXTENDED;
1683         ch->ccw[6].flags = CCW_FLAG_SLI;
1684
1685         ch->ccw[7].cmd_code = CCW_CMD_NOOP;
1686         ch->ccw[7].flags = CCW_FLAG_SLI;
1687
1688         ch->cdev = cdev;
1689         snprintf(ch->id, CTC_ID_SIZE, "ch-%s", cdev->dev.bus_id);
1690         ch->type = type;
1691         ch->fsm = init_fsm(ch->id, ch_state_names,
1692                            ch_event_names, NR_CH_STATES, NR_CH_EVENTS,
1693                            ch_fsm, CH_FSM_LEN, GFP_KERNEL);
1694         if (ch->fsm == NULL) {
1695                 ctc_pr_warn("ctc: Could not create FSM in add_channel\n");
1696                 kfree(ch->ccw);
1697                 kfree(ch);
1698                 return -1;
1699         }
1700         fsm_newstate(ch->fsm, CH_STATE_IDLE);
1701         if ((ch->irb = (struct irb *) kmalloc(sizeof (struct irb),
1702                                               GFP_KERNEL)) == NULL) {
1703                 ctc_pr_warn("ctc: Out of memory in add_channel\n");
1704                 kfree_fsm(ch->fsm);
1705                 kfree(ch->ccw);
1706                 kfree(ch);
1707                 return -1;
1708         }
1709         memset(ch->irb, 0, sizeof (struct irb));
1710         while (*c && less_than((*c)->id, ch->id))
1711                 c = &(*c)->next;
1712         if (*c && (!strncmp((*c)->id, ch->id, CTC_ID_SIZE))) {
1713                 ctc_pr_debug(
1714                         "ctc: add_channel: device %s already in list, "
1715                         "using old entry\n", (*c)->id);
1716                 kfree(ch->irb);
1717                 kfree_fsm(ch->fsm);
1718                 kfree(ch->ccw);
1719                 kfree(ch);
1720                 return 0;
1721         }
1722         fsm_settimer(ch->fsm, &ch->timer);
1723         skb_queue_head_init(&ch->io_queue);
1724         skb_queue_head_init(&ch->collect_queue);
1725         ch->next = *c;
1726         *c = ch;
1727         return 0;
1728 }
1729
1730 /**
1731  * Release a specific channel in the channel list.
1732  *
1733  * @param ch Pointer to channel struct to be released.
1734  */
1735 static void
1736 channel_free(struct channel *ch)
1737 {
1738         ch->flags &= ~CHANNEL_FLAGS_INUSE;
1739         fsm_newstate(ch->fsm, CH_STATE_IDLE);
1740 }
1741
1742 /**
1743  * Remove a specific channel in the channel list.
1744  *
1745  * @param ch Pointer to channel struct to be released.
1746  */
1747 static void
1748 channel_remove(struct channel *ch)
1749 {
1750         struct channel **c = &channels;
1751
1752         DBF_TEXT(trace, 2, __FUNCTION__);
1753         if (ch == NULL)
1754                 return;
1755
1756         channel_free(ch);
1757         while (*c) {
1758                 if (*c == ch) {
1759                         *c = ch->next;
1760                         fsm_deltimer(&ch->timer);
1761                         kfree_fsm(ch->fsm);
1762                         clear_normalized_cda(&ch->ccw[4]);
1763                         if (ch->trans_skb != NULL) {
1764                                 clear_normalized_cda(&ch->ccw[1]);
1765                                 dev_kfree_skb(ch->trans_skb);
1766                         }
1767                         kfree(ch->ccw);
1768                         kfree(ch->irb);
1769                         kfree(ch);
1770                         return;
1771                 }
1772                 c = &((*c)->next);
1773         }
1774 }
1775
1776 /**
1777  * Get a specific channel from the channel list.
1778  *
1779  * @param type Type of channel we are interested in.
1780  * @param id Id of channel we are interested in.
1781  * @param direction Direction we want to use this channel for.
1782  *
1783  * @return Pointer to a channel or NULL if no matching channel available.
1784  */
1785 static struct channel
1786 *
1787 channel_get(enum channel_types type, char *id, int direction)
1788 {
1789         struct channel *ch = channels;
1790
1791         DBF_TEXT(trace, 3, __FUNCTION__);
1792 #ifdef DEBUG
1793         ctc_pr_debug("ctc: %s(): searching for ch with id %s and type %d\n",
1794                      __func__, id, type);
1795 #endif
1796
1797         while (ch && ((strncmp(ch->id, id, CTC_ID_SIZE)) || (ch->type != type))) {
1798 #ifdef DEBUG
1799                 ctc_pr_debug("ctc: %s(): ch=0x%p (id=%s, type=%d\n",
1800                              __func__, ch, ch->id, ch->type);
1801 #endif
1802                 ch = ch->next;
1803         }
1804 #ifdef DEBUG
1805         ctc_pr_debug("ctc: %s(): ch=0x%pq (id=%s, type=%d\n",
1806                      __func__, ch, ch->id, ch->type);
1807 #endif
1808         if (!ch) {
1809                 ctc_pr_warn("ctc: %s(): channel with id %s "
1810                             "and type %d not found in channel list\n",
1811                             __func__, id, type);
1812         } else {
1813                 if (ch->flags & CHANNEL_FLAGS_INUSE)
1814                         ch = NULL;
1815                 else {
1816                         ch->flags |= CHANNEL_FLAGS_INUSE;
1817                         ch->flags &= ~CHANNEL_FLAGS_RWMASK;
1818                         ch->flags |= (direction == WRITE)
1819                             ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
1820                         fsm_newstate(ch->fsm, CH_STATE_STOPPED);
1821                 }
1822         }
1823         return ch;
1824 }
1825
1826 /**
1827  * Return the channel type by name.
1828  *
1829  * @param name Name of network interface.
1830  *
1831  * @return Type class of channel to be used for that interface.
1832  */
1833 static enum channel_types inline
1834 extract_channel_media(char *name)
1835 {
1836         enum channel_types ret = channel_type_unknown;
1837
1838         if (name != NULL) {
1839                 if (strncmp(name, "ctc", 3) == 0)
1840                         ret = channel_type_parallel;
1841                 if (strncmp(name, "escon", 5) == 0)
1842                         ret = channel_type_escon;
1843         }
1844         return ret;
1845 }
1846
1847 static long
1848 __ctc_check_irb_error(struct ccw_device *cdev, struct irb *irb)
1849 {
1850         if (!IS_ERR(irb))
1851                 return 0;
1852
1853         switch (PTR_ERR(irb)) {
1854         case -EIO:
1855                 ctc_pr_warn("i/o-error on device %s\n", cdev->dev.bus_id);
1856 //              CTC_DBF_TEXT(trace, 2, "ckirberr");
1857 //              CTC_DBF_TEXT_(trace, 2, "  rc%d", -EIO);
1858                 break;
1859         case -ETIMEDOUT:
1860                 ctc_pr_warn("timeout on device %s\n", cdev->dev.bus_id);
1861 //              CTC_DBF_TEXT(trace, 2, "ckirberr");
1862 //              CTC_DBF_TEXT_(trace, 2, "  rc%d", -ETIMEDOUT);
1863                 break;
1864         default:
1865                 ctc_pr_warn("unknown error %ld on device %s\n", PTR_ERR(irb),
1866                            cdev->dev.bus_id);
1867 //              CTC_DBF_TEXT(trace, 2, "ckirberr");
1868 //              CTC_DBF_TEXT(trace, 2, "  rc???");
1869         }
1870         return PTR_ERR(irb);
1871 }
1872
1873 /**
1874  * Main IRQ handler.
1875  *
1876  * @param cdev    The ccw_device the interrupt is for.
1877  * @param intparm interruption parameter.
1878  * @param irb     interruption response block.
1879  */
1880 static void
1881 ctc_irq_handler(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
1882 {
1883         struct channel *ch;
1884         struct net_device *dev;
1885         struct ctc_priv *priv;
1886
1887         DBF_TEXT(trace, 5, __FUNCTION__);
1888         if (__ctc_check_irb_error(cdev, irb))
1889                 return;
1890
1891         /* Check for unsolicited interrupts. */
1892         if (!cdev->dev.driver_data) {
1893                 ctc_pr_warn("ctc: Got unsolicited irq: %s c-%02x d-%02x\n",
1894                             cdev->dev.bus_id, irb->scsw.cstat,
1895                             irb->scsw.dstat);
1896                 return;
1897         }
1898
1899         priv = ((struct ccwgroup_device *)cdev->dev.driver_data)
1900                 ->dev.driver_data;
1901
1902         /* Try to extract channel from driver data. */
1903         if (priv->channel[READ]->cdev == cdev)
1904                 ch = priv->channel[READ];
1905         else if (priv->channel[WRITE]->cdev == cdev)
1906                 ch = priv->channel[WRITE];
1907         else {
1908                 ctc_pr_err("ctc: Can't determine channel for interrupt, "
1909                            "device %s\n", cdev->dev.bus_id);
1910                 return;
1911         }
1912
1913         dev = (struct net_device *) (ch->netdev);
1914         if (dev == NULL) {
1915                 ctc_pr_crit("ctc: ctc_irq_handler dev=NULL bus_id=%s, ch=0x%p\n",
1916                             cdev->dev.bus_id, ch);
1917                 return;
1918         }
1919
1920 #ifdef DEBUG
1921         ctc_pr_debug("%s: interrupt for device: %s received c-%02x d-%02x\n",
1922                      dev->name, ch->id, irb->scsw.cstat, irb->scsw.dstat);
1923 #endif
1924
1925         /* Copy interruption response block. */
1926         memcpy(ch->irb, irb, sizeof(struct irb));
1927
1928         /* Check for good subchannel return code, otherwise error message */
1929         if (ch->irb->scsw.cstat) {
1930                 fsm_event(ch->fsm, CH_EVENT_SC_UNKNOWN, ch);
1931                 ctc_pr_warn("%s: subchannel check for device: %s - %02x %02x\n",
1932                             dev->name, ch->id, ch->irb->scsw.cstat,
1933                             ch->irb->scsw.dstat);
1934                 return;
1935         }
1936
1937         /* Check the reason-code of a unit check */
1938         if (ch->irb->scsw.dstat & DEV_STAT_UNIT_CHECK) {
1939                 ccw_unit_check(ch, ch->irb->ecw[0]);
1940                 return;
1941         }
1942         if (ch->irb->scsw.dstat & DEV_STAT_BUSY) {
1943                 if (ch->irb->scsw.dstat & DEV_STAT_ATTENTION)
1944                         fsm_event(ch->fsm, CH_EVENT_ATTNBUSY, ch);
1945                 else
1946                         fsm_event(ch->fsm, CH_EVENT_BUSY, ch);
1947                 return;
1948         }
1949         if (ch->irb->scsw.dstat & DEV_STAT_ATTENTION) {
1950                 fsm_event(ch->fsm, CH_EVENT_ATTN, ch);
1951                 return;
1952         }
1953         if ((ch->irb->scsw.stctl & SCSW_STCTL_SEC_STATUS) ||
1954             (ch->irb->scsw.stctl == SCSW_STCTL_STATUS_PEND) ||
1955             (ch->irb->scsw.stctl ==
1956              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1957                 fsm_event(ch->fsm, CH_EVENT_FINSTAT, ch);
1958         else
1959                 fsm_event(ch->fsm, CH_EVENT_IRQ, ch);
1960
1961 }
1962
1963 /**
1964  * Actions for interface - statemachine.
1965  *****************************************************************************/
1966
1967 /**
1968  * Startup channels by sending CH_EVENT_START to each channel.
1969  *
1970  * @param fi    An instance of an interface statemachine.
1971  * @param event The event, just happened.
1972  * @param arg   Generic pointer, casted from struct net_device * upon call.
1973  */
1974 static void
1975 dev_action_start(fsm_instance * fi, int event, void *arg)
1976 {
1977         struct net_device *dev = (struct net_device *) arg;
1978         struct ctc_priv *privptr = dev->priv;
1979         int direction;
1980
1981         DBF_TEXT(setup, 3, __FUNCTION__);
1982         fsm_deltimer(&privptr->restart_timer);
1983         fsm_newstate(fi, DEV_STATE_STARTWAIT_RXTX);
1984         for (direction = READ; direction <= WRITE; direction++) {
1985                 struct channel *ch = privptr->channel[direction];
1986                 fsm_event(ch->fsm, CH_EVENT_START, ch);
1987         }
1988 }
1989
1990 /**
1991  * Shutdown channels by sending CH_EVENT_STOP to each channel.
1992  *
1993  * @param fi    An instance of an interface statemachine.
1994  * @param event The event, just happened.
1995  * @param arg   Generic pointer, casted from struct net_device * upon call.
1996  */
1997 static void
1998 dev_action_stop(fsm_instance * fi, int event, void *arg)
1999 {
2000         struct net_device *dev = (struct net_device *) arg;
2001         struct ctc_priv *privptr = dev->priv;
2002         int direction;
2003
2004         DBF_TEXT(trace, 3, __FUNCTION__);
2005         fsm_newstate(fi, DEV_STATE_STOPWAIT_RXTX);
2006         for (direction = READ; direction <= WRITE; direction++) {
2007                 struct channel *ch = privptr->channel[direction];
2008                 fsm_event(ch->fsm, CH_EVENT_STOP, ch);
2009         }
2010 }
2011 static void
2012 dev_action_restart(fsm_instance *fi, int event, void *arg)
2013 {
2014         struct net_device *dev = (struct net_device *)arg;
2015         struct ctc_priv *privptr = dev->priv;
2016
2017         DBF_TEXT(trace, 3, __FUNCTION__);
2018         ctc_pr_debug("%s: Restarting\n", dev->name);
2019         dev_action_stop(fi, event, arg);
2020         fsm_event(privptr->fsm, DEV_EVENT_STOP, dev);
2021         fsm_addtimer(&privptr->restart_timer, CTC_TIMEOUT_5SEC,
2022                      DEV_EVENT_START, dev);
2023 }
2024
2025 /**
2026  * Called from channel statemachine
2027  * when a channel is up and running.
2028  *
2029  * @param fi    An instance of an interface statemachine.
2030  * @param event The event, just happened.
2031  * @param arg   Generic pointer, casted from struct net_device * upon call.
2032  */
2033 static void
2034 dev_action_chup(fsm_instance * fi, int event, void *arg)
2035 {
2036         struct net_device *dev = (struct net_device *) arg;
2037         struct ctc_priv *privptr = dev->priv;
2038
2039         DBF_TEXT(trace, 3, __FUNCTION__);
2040         switch (fsm_getstate(fi)) {
2041                 case DEV_STATE_STARTWAIT_RXTX:
2042                         if (event == DEV_EVENT_RXUP)
2043                                 fsm_newstate(fi, DEV_STATE_STARTWAIT_TX);
2044                         else
2045                                 fsm_newstate(fi, DEV_STATE_STARTWAIT_RX);
2046                         break;
2047                 case DEV_STATE_STARTWAIT_RX:
2048                         if (event == DEV_EVENT_RXUP) {
2049                                 fsm_newstate(fi, DEV_STATE_RUNNING);
2050                                 ctc_pr_info("%s: connected with remote side\n",
2051                                             dev->name);
2052                                 if (privptr->protocol == CTC_PROTO_LINUX_TTY)
2053                                         ctc_tty_setcarrier(dev, 1);
2054                                 ctc_clear_busy(dev);
2055                         }
2056                         break;
2057                 case DEV_STATE_STARTWAIT_TX:
2058                         if (event == DEV_EVENT_TXUP) {
2059                                 fsm_newstate(fi, DEV_STATE_RUNNING);
2060                                 ctc_pr_info("%s: connected with remote side\n",
2061                                             dev->name);
2062                                 if (privptr->protocol == CTC_PROTO_LINUX_TTY)
2063                                         ctc_tty_setcarrier(dev, 1);
2064                                 ctc_clear_busy(dev);
2065                         }
2066                         break;
2067                 case DEV_STATE_STOPWAIT_TX:
2068                         if (event == DEV_EVENT_RXUP)
2069                                 fsm_newstate(fi, DEV_STATE_STOPWAIT_RXTX);
2070                         break;
2071                 case DEV_STATE_STOPWAIT_RX:
2072                         if (event == DEV_EVENT_TXUP)
2073                                 fsm_newstate(fi, DEV_STATE_STOPWAIT_RXTX);
2074                         break;
2075         }
2076 }
2077
2078 /**
2079  * Called from channel statemachine
2080  * when a channel has been shutdown.
2081  *
2082  * @param fi    An instance of an interface statemachine.
2083  * @param event The event, just happened.
2084  * @param arg   Generic pointer, casted from struct net_device * upon call.
2085  */
2086 static void
2087 dev_action_chdown(fsm_instance * fi, int event, void *arg)
2088 {
2089         struct net_device *dev = (struct net_device *) arg;
2090         struct ctc_priv *privptr = dev->priv;
2091
2092         DBF_TEXT(trace, 3, __FUNCTION__);
2093         switch (fsm_getstate(fi)) {
2094                 case DEV_STATE_RUNNING:
2095                         if (privptr->protocol == CTC_PROTO_LINUX_TTY)
2096                                 ctc_tty_setcarrier(dev, 0);
2097                         if (event == DEV_EVENT_TXDOWN)
2098                                 fsm_newstate(fi, DEV_STATE_STARTWAIT_TX);
2099                         else
2100                                 fsm_newstate(fi, DEV_STATE_STARTWAIT_RX);
2101                         break;
2102                 case DEV_STATE_STARTWAIT_RX:
2103                         if (event == DEV_EVENT_TXDOWN)
2104                                 fsm_newstate(fi, DEV_STATE_STARTWAIT_RXTX);
2105                         break;
2106                 case DEV_STATE_STARTWAIT_TX:
2107                         if (event == DEV_EVENT_RXDOWN)
2108                                 fsm_newstate(fi, DEV_STATE_STARTWAIT_RXTX);
2109                         break;
2110                 case DEV_STATE_STOPWAIT_RXTX:
2111                         if (event == DEV_EVENT_TXDOWN)
2112                                 fsm_newstate(fi, DEV_STATE_STOPWAIT_RX);
2113                         else
2114                                 fsm_newstate(fi, DEV_STATE_STOPWAIT_TX);
2115                         break;
2116                 case DEV_STATE_STOPWAIT_RX:
2117                         if (event == DEV_EVENT_RXDOWN)
2118                                 fsm_newstate(fi, DEV_STATE_STOPPED);
2119                         break;
2120                 case DEV_STATE_STOPWAIT_TX:
2121                         if (event == DEV_EVENT_TXDOWN)
2122                                 fsm_newstate(fi, DEV_STATE_STOPPED);
2123                         break;
2124         }
2125 }
2126
2127 static const fsm_node dev_fsm[] = {
2128         {DEV_STATE_STOPPED, DEV_EVENT_START, dev_action_start},
2129
2130         {DEV_STATE_STOPWAIT_RXTX,  DEV_EVENT_START,   dev_action_start   },
2131         {DEV_STATE_STOPWAIT_RXTX,  DEV_EVENT_RXDOWN,  dev_action_chdown  },
2132         {DEV_STATE_STOPWAIT_RXTX,  DEV_EVENT_TXDOWN,  dev_action_chdown  },
2133         {DEV_STATE_STOPWAIT_RXTX,  DEV_EVENT_RESTART, dev_action_restart },
2134
2135         {DEV_STATE_STOPWAIT_RX,    DEV_EVENT_START,   dev_action_start   },
2136         {DEV_STATE_STOPWAIT_RX,    DEV_EVENT_RXUP,    dev_action_chup    },
2137         {DEV_STATE_STOPWAIT_RX,    DEV_EVENT_TXUP,    dev_action_chup    },
2138         {DEV_STATE_STOPWAIT_RX,    DEV_EVENT_RXDOWN,  dev_action_chdown  },
2139         {DEV_STATE_STOPWAIT_RX,    DEV_EVENT_RESTART, dev_action_restart },
2140
2141         {DEV_STATE_STOPWAIT_TX,    DEV_EVENT_START,   dev_action_start   },
2142         {DEV_STATE_STOPWAIT_TX,    DEV_EVENT_RXUP,    dev_action_chup    },
2143         {DEV_STATE_STOPWAIT_TX,    DEV_EVENT_TXUP,    dev_action_chup    },
2144         {DEV_STATE_STOPWAIT_TX,    DEV_EVENT_TXDOWN,  dev_action_chdown  },
2145         {DEV_STATE_STOPWAIT_TX,    DEV_EVENT_RESTART, dev_action_restart },
2146
2147         {DEV_STATE_STARTWAIT_RXTX, DEV_EVENT_STOP,    dev_action_stop    },
2148         {DEV_STATE_STARTWAIT_RXTX, DEV_EVENT_RXUP,    dev_action_chup    },
2149         {DEV_STATE_STARTWAIT_RXTX, DEV_EVENT_TXUP,    dev_action_chup    },
2150         {DEV_STATE_STARTWAIT_RXTX, DEV_EVENT_RXDOWN,  dev_action_chdown  },
2151         {DEV_STATE_STARTWAIT_RXTX, DEV_EVENT_TXDOWN,  dev_action_chdown  },
2152         {DEV_STATE_STARTWAIT_RXTX, DEV_EVENT_RESTART, dev_action_restart },
2153
2154         {DEV_STATE_STARTWAIT_TX,   DEV_EVENT_STOP,    dev_action_stop    },
2155         {DEV_STATE_STARTWAIT_TX,   DEV_EVENT_RXUP,    dev_action_chup    },
2156         {DEV_STATE_STARTWAIT_TX,   DEV_EVENT_TXUP,    dev_action_chup    },
2157         {DEV_STATE_STARTWAIT_TX,   DEV_EVENT_RXDOWN,  dev_action_chdown  },
2158         {DEV_STATE_STARTWAIT_TX,   DEV_EVENT_RESTART, dev_action_restart },
2159
2160         {DEV_STATE_STARTWAIT_RX,   DEV_EVENT_STOP,    dev_action_stop    },
2161         {DEV_STATE_STARTWAIT_RX,   DEV_EVENT_RXUP,    dev_action_chup    },
2162         {DEV_STATE_STARTWAIT_RX,   DEV_EVENT_TXUP,    dev_action_chup    },
2163         {DEV_STATE_STARTWAIT_RX,   DEV_EVENT_TXDOWN,  dev_action_chdown  },
2164         {DEV_STATE_STARTWAIT_RX,   DEV_EVENT_RESTART, dev_action_restart },
2165
2166         {DEV_STATE_RUNNING,        DEV_EVENT_STOP,    dev_action_stop    },
2167         {DEV_STATE_RUNNING,        DEV_EVENT_RXDOWN,  dev_action_chdown  },
2168         {DEV_STATE_RUNNING,        DEV_EVENT_TXDOWN,  dev_action_chdown  },
2169         {DEV_STATE_RUNNING,        DEV_EVENT_TXUP,    fsm_action_nop     },
2170         {DEV_STATE_RUNNING,        DEV_EVENT_RXUP,    fsm_action_nop     },
2171         {DEV_STATE_RUNNING,        DEV_EVENT_RESTART, dev_action_restart },
2172 };
2173
2174 static const int DEV_FSM_LEN = sizeof (dev_fsm) / sizeof (fsm_node);
2175
2176 /**
2177  * Transmit a packet.
2178  * This is a helper function for ctc_tx().
2179  *
2180  * @param ch Channel to be used for sending.
2181  * @param skb Pointer to struct sk_buff of packet to send.
2182  *            The linklevel header has already been set up
2183  *            by ctc_tx().
2184  *
2185  * @return 0 on success, -ERRNO on failure. (Never fails.)
2186  */
2187 static int
2188 transmit_skb(struct channel *ch, struct sk_buff *skb)
2189 {
2190         unsigned long saveflags;
2191         struct ll_header header;
2192         int rc = 0;
2193
2194         DBF_TEXT(trace, 5, __FUNCTION__);
2195         /* we need to acquire the lock for testing the state
2196          * otherwise we can have an IRQ changing the state to
2197          * TXIDLE after the test but before acquiring the lock.
2198          */
2199         spin_lock_irqsave(&ch->collect_lock, saveflags);
2200         if (fsm_getstate(ch->fsm) != CH_STATE_TXIDLE) {
2201                 int l = skb->len + LL_HEADER_LENGTH;
2202
2203                 if (ch->collect_len + l > ch->max_bufsize - 2) {
2204                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
2205                         return -EBUSY;
2206                 } else {
2207                         atomic_inc(&skb->users);
2208                         header.length = l;
2209                         header.type = skb->protocol;
2210                         header.unused = 0;
2211                         memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
2212                                LL_HEADER_LENGTH);
2213                         skb_queue_tail(&ch->collect_queue, skb);
2214                         ch->collect_len += l;
2215                 }
2216                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
2217         } else {
2218                 __u16 block_len;
2219                 int ccw_idx;
2220                 struct sk_buff *nskb;
2221                 unsigned long hi;
2222                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
2223                 /**
2224                  * Protect skb against beeing free'd by upper
2225                  * layers.
2226                  */
2227                 atomic_inc(&skb->users);
2228                 ch->prof.txlen += skb->len;
2229                 header.length = skb->len + LL_HEADER_LENGTH;
2230                 header.type = skb->protocol;
2231                 header.unused = 0;
2232                 memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
2233                        LL_HEADER_LENGTH);
2234                 block_len = skb->len + 2;
2235                 *((__u16 *) skb_push(skb, 2)) = block_len;
2236
2237                 /**
2238                  * IDAL support in CTC is broken, so we have to
2239                  * care about skb's above 2G ourselves.
2240                  */
2241                 hi = ((unsigned long) skb->tail + LL_HEADER_LENGTH) >> 31;
2242                 if (hi) {
2243                         nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
2244                         if (!nskb) {
2245                                 atomic_dec(&skb->users);
2246                                 skb_pull(skb, LL_HEADER_LENGTH + 2);
2247                                 ctc_clear_busy(ch->netdev);
2248                                 return -ENOMEM;
2249                         } else {
2250                                 memcpy(skb_put(nskb, skb->len),
2251                                        skb->data, skb->len);
2252                                 atomic_inc(&nskb->users);
2253                                 atomic_dec(&skb->users);
2254                                 dev_kfree_skb_irq(skb);
2255                                 skb = nskb;
2256                         }
2257                 }
2258
2259                 ch->ccw[4].count = block_len;
2260                 if (set_normalized_cda(&ch->ccw[4], skb->data)) {
2261                         /**
2262                          * idal allocation failed, try via copying to
2263                          * trans_skb. trans_skb usually has a pre-allocated
2264                          * idal.
2265                          */
2266                         if (ctc_checkalloc_buffer(ch, 1)) {
2267                                 /**
2268                                  * Remove our header. It gets added
2269                                  * again on retransmit.
2270                                  */
2271                                 atomic_dec(&skb->users);
2272                                 skb_pull(skb, LL_HEADER_LENGTH + 2);
2273                                 ctc_clear_busy(ch->netdev);
2274                                 return -EBUSY;
2275                         }
2276
2277                         ch->trans_skb->tail = ch->trans_skb->data;
2278                         ch->trans_skb->len = 0;
2279                         ch->ccw[1].count = skb->len;
2280                         memcpy(skb_put(ch->trans_skb, skb->len), skb->data,
2281                                skb->len);
2282                         atomic_dec(&skb->users);
2283                         dev_kfree_skb_irq(skb);
2284                         ccw_idx = 0;
2285                 } else {
2286                         skb_queue_tail(&ch->io_queue, skb);
2287                         ccw_idx = 3;
2288                 }
2289                 ch->retry = 0;
2290                 fsm_newstate(ch->fsm, CH_STATE_TX);
2291                 fsm_addtimer(&ch->timer, CTC_TIMEOUT_5SEC, CH_EVENT_TIMER, ch);
2292                 spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
2293                 ch->prof.send_stamp = xtime;
2294                 rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx],
2295                                       (unsigned long) ch, 0xff, 0);
2296                 spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
2297                 if (ccw_idx == 3)
2298                         ch->prof.doios_single++;
2299                 if (rc != 0) {
2300                         fsm_deltimer(&ch->timer);
2301                         ccw_check_return_code(ch, rc, "single skb TX");
2302                         if (ccw_idx == 3)
2303                                 skb_dequeue_tail(&ch->io_queue);
2304                         /**
2305                          * Remove our header. It gets added
2306                          * again on retransmit.
2307                          */
2308                         skb_pull(skb, LL_HEADER_LENGTH + 2);
2309                 } else {
2310                         if (ccw_idx == 0) {
2311                                 struct net_device *dev = ch->netdev;
2312                                 struct ctc_priv *privptr = dev->priv;
2313                                 privptr->stats.tx_packets++;
2314                                 privptr->stats.tx_bytes +=
2315                                     skb->len - LL_HEADER_LENGTH;
2316                         }
2317                 }
2318         }
2319
2320         ctc_clear_busy(ch->netdev);
2321         return rc;
2322 }
2323
2324 /**
2325  * Interface API for upper network layers
2326  *****************************************************************************/
2327
2328 /**
2329  * Open an interface.
2330  * Called from generic network layer when ifconfig up is run.
2331  *
2332  * @param dev Pointer to interface struct.
2333  *
2334  * @return 0 on success, -ERRNO on failure. (Never fails.)
2335  */
2336 static int
2337 ctc_open(struct net_device * dev)
2338 {
2339         DBF_TEXT(trace, 5, __FUNCTION__);
2340         fsm_event(((struct ctc_priv *) dev->priv)->fsm, DEV_EVENT_START, dev);
2341         return 0;
2342 }
2343
2344 /**
2345  * Close an interface.
2346  * Called from generic network layer when ifconfig down is run.
2347  *
2348  * @param dev Pointer to interface struct.
2349  *
2350  * @return 0 on success, -ERRNO on failure. (Never fails.)
2351  */
2352 static int
2353 ctc_close(struct net_device * dev)
2354 {
2355         DBF_TEXT(trace, 5, __FUNCTION__);
2356         fsm_event(((struct ctc_priv *) dev->priv)->fsm, DEV_EVENT_STOP, dev);
2357         return 0;
2358 }
2359
2360 /**
2361  * Start transmission of a packet.
2362  * Called from generic network device layer.
2363  *
2364  * @param skb Pointer to buffer containing the packet.
2365  * @param dev Pointer to interface struct.
2366  *
2367  * @return 0 if packet consumed, !0 if packet rejected.
2368  *         Note: If we return !0, then the packet is free'd by
2369  *               the generic network layer.
2370  */
2371 static int
2372 ctc_tx(struct sk_buff *skb, struct net_device * dev)
2373 {
2374         int rc = 0;
2375         struct ctc_priv *privptr = (struct ctc_priv *) dev->priv;
2376
2377         DBF_TEXT(trace, 5, __FUNCTION__);
2378         /**
2379          * Some sanity checks ...
2380          */
2381         if (skb == NULL) {
2382                 ctc_pr_warn("%s: NULL sk_buff passed\n", dev->name);
2383                 privptr->stats.tx_dropped++;
2384                 return 0;
2385         }
2386         if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
2387                 ctc_pr_warn("%s: Got sk_buff with head room < %ld bytes\n",
2388                             dev->name, LL_HEADER_LENGTH + 2);
2389                 dev_kfree_skb(skb);
2390                 privptr->stats.tx_dropped++;
2391                 return 0;
2392         }
2393
2394         /**
2395          * If channels are not running, try to restart them
2396          * and throw away packet.
2397          */
2398         if (fsm_getstate(privptr->fsm) != DEV_STATE_RUNNING) {
2399                 fsm_event(privptr->fsm, DEV_EVENT_START, dev);
2400                 if (privptr->protocol == CTC_PROTO_LINUX_TTY)
2401                         return -EBUSY;
2402                 dev_kfree_skb(skb);
2403                 privptr->stats.tx_dropped++;
2404                 privptr->stats.tx_errors++;
2405                 privptr->stats.tx_carrier_errors++;
2406                 return 0;
2407         }
2408
2409         if (ctc_test_and_set_busy(dev))
2410                 return -EBUSY;
2411
2412         dev->trans_start = jiffies;
2413         if (transmit_skb(privptr->channel[WRITE], skb) != 0)
2414                 rc = 1;
2415         return rc;
2416 }
2417
2418 /**
2419  * Sets MTU of an interface.
2420  *
2421  * @param dev     Pointer to interface struct.
2422  * @param new_mtu The new MTU to use for this interface.
2423  *
2424  * @return 0 on success, -EINVAL if MTU is out of valid range.
2425  *         (valid range is 576 .. 65527). If VM is on the
2426  *         remote side, maximum MTU is 32760, however this is
2427  *         <em>not</em> checked here.
2428  */
2429 static int
2430 ctc_change_mtu(struct net_device * dev, int new_mtu)
2431 {
2432         struct ctc_priv *privptr = (struct ctc_priv *) dev->priv;
2433
2434         DBF_TEXT(trace, 3, __FUNCTION__);
2435         if ((new_mtu < 576) || (new_mtu > 65527) ||
2436             (new_mtu > (privptr->channel[READ]->max_bufsize -
2437                         LL_HEADER_LENGTH - 2)))
2438                 return -EINVAL;
2439         dev->mtu = new_mtu;
2440         dev->hard_header_len = LL_HEADER_LENGTH + 2;
2441         return 0;
2442 }
2443
2444 /**
2445  * Returns interface statistics of a device.
2446  *
2447  * @param dev Pointer to interface struct.
2448  *
2449  * @return Pointer to stats struct of this interface.
2450  */
2451 static struct net_device_stats *
2452 ctc_stats(struct net_device * dev)
2453 {
2454         return &((struct ctc_priv *) dev->priv)->stats;
2455 }
2456
2457 /*
2458  * sysfs attributes
2459  */
2460
2461 static ssize_t
2462 buffer_show(struct device *dev, struct device_attribute *attr, char *buf)
2463 {
2464         struct ctc_priv *priv;
2465
2466         priv = dev->driver_data;
2467         if (!priv)
2468                 return -ENODEV;
2469         return sprintf(buf, "%d\n",
2470                         priv->buffer_size);
2471 }
2472
2473 static ssize_t
2474 buffer_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
2475 {
2476         struct ctc_priv *priv;
2477         struct net_device *ndev;
2478         int bs1;
2479         char buffer[16];
2480
2481         DBF_TEXT(trace, 3, __FUNCTION__);
2482         DBF_TEXT(trace, 3, buf);
2483         priv = dev->driver_data;
2484         if (!priv) {
2485                 DBF_TEXT(trace, 3, "bfnopriv");
2486                 return -ENODEV;
2487         }
2488
2489         sscanf(buf, "%u", &bs1);
2490         if (bs1 > CTC_BUFSIZE_LIMIT)
2491                 goto einval;
2492         if (bs1 < (576 + LL_HEADER_LENGTH + 2))
2493                 goto einval;
2494         priv->buffer_size = bs1;        // just to overwrite the default
2495
2496         ndev = priv->channel[READ]->netdev;
2497         if (!ndev) {
2498                 DBF_TEXT(trace, 3, "bfnondev");
2499                 return -ENODEV;
2500         }
2501
2502         if ((ndev->flags & IFF_RUNNING) &&
2503             (bs1 < (ndev->mtu + LL_HEADER_LENGTH + 2)))
2504                 goto einval;
2505
2506         priv->channel[READ]->max_bufsize = bs1;
2507         priv->channel[WRITE]->max_bufsize = bs1;
2508         if (!(ndev->flags & IFF_RUNNING))
2509                 ndev->mtu = bs1 - LL_HEADER_LENGTH - 2;
2510         priv->channel[READ]->flags |= CHANNEL_FLAGS_BUFSIZE_CHANGED;
2511         priv->channel[WRITE]->flags |= CHANNEL_FLAGS_BUFSIZE_CHANGED;
2512
2513         sprintf(buffer, "%d",priv->buffer_size);
2514         DBF_TEXT(trace, 3, buffer);
2515         return count;
2516
2517 einval:
2518         DBF_TEXT(trace, 3, "buff_err");
2519         return -EINVAL;
2520 }
2521
2522 static ssize_t
2523 loglevel_show(struct device *dev, struct device_attribute *attr, char *buf)
2524 {
2525         return sprintf(buf, "%d\n", loglevel);
2526 }
2527
2528 static ssize_t
2529 loglevel_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
2530 {
2531         int ll1;
2532
2533         DBF_TEXT(trace, 5, __FUNCTION__);
2534         sscanf(buf, "%i", &ll1);
2535
2536         if ((ll1 > CTC_LOGLEVEL_MAX) || (ll1 < 0))
2537                 return -EINVAL;
2538         loglevel = ll1;
2539         return count;
2540 }
2541
2542 static void
2543 ctc_print_statistics(struct ctc_priv *priv)
2544 {
2545         char *sbuf;
2546         char *p;
2547
2548         DBF_TEXT(trace, 4, __FUNCTION__);
2549         if (!priv)
2550                 return;
2551         sbuf = (char *)kmalloc(2048, GFP_KERNEL);
2552         if (sbuf == NULL)
2553                 return;
2554         p = sbuf;
2555
2556         p += sprintf(p, "  Device FSM state: %s\n",
2557                      fsm_getstate_str(priv->fsm));
2558         p += sprintf(p, "  RX channel FSM state: %s\n",
2559                      fsm_getstate_str(priv->channel[READ]->fsm));
2560         p += sprintf(p, "  TX channel FSM state: %s\n",
2561                      fsm_getstate_str(priv->channel[WRITE]->fsm));
2562         p += sprintf(p, "  Max. TX buffer used: %ld\n",
2563                      priv->channel[WRITE]->prof.maxmulti);
2564         p += sprintf(p, "  Max. chained SKBs: %ld\n",
2565                      priv->channel[WRITE]->prof.maxcqueue);
2566         p += sprintf(p, "  TX single write ops: %ld\n",
2567                      priv->channel[WRITE]->prof.doios_single);
2568         p += sprintf(p, "  TX multi write ops: %ld\n",
2569                      priv->channel[WRITE]->prof.doios_multi);
2570         p += sprintf(p, "  Netto bytes written: %ld\n",
2571                      priv->channel[WRITE]->prof.txlen);
2572         p += sprintf(p, "  Max. TX IO-time: %ld\n",
2573                      priv->channel[WRITE]->prof.tx_time);
2574
2575         ctc_pr_debug("Statistics for %s:\n%s",
2576                      priv->channel[WRITE]->netdev->name, sbuf);
2577         kfree(sbuf);
2578         return;
2579 }
2580
2581 static ssize_t
2582 stats_show(struct device *dev, struct device_attribute *attr, char *buf)
2583 {
2584         struct ctc_priv *priv = dev->driver_data;
2585         if (!priv)
2586                 return -ENODEV;
2587         ctc_print_statistics(priv);
2588         return sprintf(buf, "0\n");
2589 }
2590
2591 static ssize_t
2592 stats_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
2593 {
2594         struct ctc_priv *priv = dev->driver_data;
2595         if (!priv)
2596                 return -ENODEV;
2597         /* Reset statistics */
2598         memset(&priv->channel[WRITE]->prof, 0,
2599                         sizeof(priv->channel[WRITE]->prof));
2600         return count;
2601 }
2602
2603 static void
2604 ctc_netdev_unregister(struct net_device * dev)
2605 {
2606         struct ctc_priv *privptr;
2607
2608         if (!dev)
2609                 return;
2610         privptr = (struct ctc_priv *) dev->priv;
2611         if (privptr->protocol != CTC_PROTO_LINUX_TTY)
2612                 unregister_netdev(dev);
2613         else
2614                 ctc_tty_unregister_netdev(dev);
2615 }
2616
2617 static int
2618 ctc_netdev_register(struct net_device * dev)
2619 {
2620         struct ctc_priv *privptr = (struct ctc_priv *) dev->priv;
2621         if (privptr->protocol != CTC_PROTO_LINUX_TTY)
2622                 return register_netdev(dev);
2623         else
2624                 return ctc_tty_register_netdev(dev);
2625 }
2626
2627 static void
2628 ctc_free_netdevice(struct net_device * dev, int free_dev)
2629 {
2630         struct ctc_priv *privptr;
2631         if (!dev)
2632                 return;
2633         privptr = dev->priv;
2634         if (privptr) {
2635                 if (privptr->fsm)
2636                         kfree_fsm(privptr->fsm);
2637                 kfree(privptr);
2638         }
2639 #ifdef MODULE
2640         if (free_dev)
2641                 free_netdev(dev);
2642 #endif
2643 }
2644
2645 static ssize_t
2646 ctc_proto_show(struct device *dev, struct device_attribute *attr, char *buf)
2647 {
2648         struct ctc_priv *priv;
2649
2650         priv = dev->driver_data;
2651         if (!priv)
2652                 return -ENODEV;
2653
2654         return sprintf(buf, "%d\n", priv->protocol);
2655 }
2656
2657 static ssize_t
2658 ctc_proto_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
2659 {
2660         struct ctc_priv *priv;
2661         int value;
2662
2663         DBF_TEXT(trace, 3, __FUNCTION__);
2664         pr_debug("%s() called\n", __FUNCTION__);
2665
2666         priv = dev->driver_data;
2667         if (!priv)
2668                 return -ENODEV;
2669         sscanf(buf, "%u", &value);
2670         if ((value < 0) || (value > CTC_PROTO_MAX))
2671                 return -EINVAL;
2672         priv->protocol = value;
2673
2674         return count;
2675 }
2676
2677 static ssize_t
2678 ctc_type_show(struct device *dev, struct device_attribute *attr, char *buf)
2679 {
2680         struct ccwgroup_device *cgdev;
2681
2682         cgdev = to_ccwgroupdev(dev);
2683         if (!cgdev)
2684                 return -ENODEV;
2685
2686         return sprintf(buf, "%s\n", cu3088_type[cgdev->cdev[0]->id.driver_info]);
2687 }
2688
2689 static DEVICE_ATTR(buffer, 0644, buffer_show, buffer_write);
2690 static DEVICE_ATTR(protocol, 0644, ctc_proto_show, ctc_proto_store);
2691 static DEVICE_ATTR(type, 0444, ctc_type_show, NULL);
2692
2693 static DEVICE_ATTR(loglevel, 0644, loglevel_show, loglevel_write);
2694 static DEVICE_ATTR(stats, 0644, stats_show, stats_write);
2695
2696 static struct attribute *ctc_attr[] = {
2697         &dev_attr_protocol.attr,
2698         &dev_attr_type.attr,
2699         &dev_attr_buffer.attr,
2700         NULL,
2701 };
2702
2703 static struct attribute_group ctc_attr_group = {
2704         .attrs = ctc_attr,
2705 };
2706
2707 static int
2708 ctc_add_attributes(struct device *dev)
2709 {
2710         device_create_file(dev, &dev_attr_loglevel);
2711         device_create_file(dev, &dev_attr_stats);
2712         return 0;
2713 }
2714
2715 static void
2716 ctc_remove_attributes(struct device *dev)
2717 {
2718         device_remove_file(dev, &dev_attr_stats);
2719         device_remove_file(dev, &dev_attr_loglevel);
2720 }
2721
2722 static int
2723 ctc_add_files(struct device *dev)
2724 {
2725         pr_debug("%s() called\n", __FUNCTION__);
2726
2727         return sysfs_create_group(&dev->kobj, &ctc_attr_group);
2728 }
2729
2730 static void
2731 ctc_remove_files(struct device *dev)
2732 {
2733         pr_debug("%s() called\n", __FUNCTION__);
2734
2735         sysfs_remove_group(&dev->kobj, &ctc_attr_group);
2736 }
2737
2738 /**
2739  * Add ctc specific attributes.
2740  * Add ctc private data.
2741  *
2742  * @param cgdev pointer to ccwgroup_device just added
2743  *
2744  * @returns 0 on success, !0 on failure.
2745  */
2746 static int
2747 ctc_probe_device(struct ccwgroup_device *cgdev)
2748 {
2749         struct ctc_priv *priv;
2750         int rc;
2751         char buffer[16];
2752
2753         pr_debug("%s() called\n", __FUNCTION__);
2754         DBF_TEXT(setup, 3, __FUNCTION__);
2755
2756         if (!get_device(&cgdev->dev))
2757                 return -ENODEV;
2758
2759         priv = kmalloc(sizeof (struct ctc_priv), GFP_KERNEL);
2760         if (!priv) {
2761                 ctc_pr_err("%s: Out of memory\n", __func__);
2762                 put_device(&cgdev->dev);
2763                 return -ENOMEM;
2764         }
2765
2766         memset(priv, 0, sizeof (struct ctc_priv));
2767         rc = ctc_add_files(&cgdev->dev);
2768         if (rc) {
2769                 kfree(priv);
2770                 put_device(&cgdev->dev);
2771                 return rc;
2772         }
2773         priv->buffer_size = CTC_BUFSIZE_DEFAULT;
2774         cgdev->cdev[0]->handler = ctc_irq_handler;
2775         cgdev->cdev[1]->handler = ctc_irq_handler;
2776         cgdev->dev.driver_data = priv;
2777
2778         sprintf(buffer, "%p", priv);
2779         DBF_TEXT(data, 3, buffer);
2780
2781         sprintf(buffer, "%u", (unsigned int)sizeof(struct ctc_priv));
2782         DBF_TEXT(data, 3, buffer);
2783
2784         sprintf(buffer, "%p", &channels);
2785         DBF_TEXT(data, 3, buffer);
2786
2787         sprintf(buffer, "%u", (unsigned int)sizeof(struct channel));
2788         DBF_TEXT(data, 3, buffer);
2789
2790         return 0;
2791 }
2792
2793 /**
2794  * Initialize everything of the net device except the name and the
2795  * channel structs.
2796  */
2797 static struct net_device *
2798 ctc_init_netdevice(struct net_device * dev, int alloc_device,
2799                    struct ctc_priv *privptr)
2800 {
2801         if (!privptr)
2802                 return NULL;
2803
2804         DBF_TEXT(setup, 3, __FUNCTION__);
2805
2806         if (alloc_device) {
2807                 dev = kmalloc(sizeof (struct net_device), GFP_KERNEL);
2808                 if (!dev)
2809                         return NULL;
2810                 memset(dev, 0, sizeof (struct net_device));
2811         }
2812
2813         dev->priv = privptr;
2814         privptr->fsm = init_fsm("ctcdev", dev_state_names,
2815                                 dev_event_names, CTC_NR_DEV_STATES, CTC_NR_DEV_EVENTS,
2816                                 dev_fsm, DEV_FSM_LEN, GFP_KERNEL);
2817         if (privptr->fsm == NULL) {
2818                 if (alloc_device)
2819                         kfree(dev);
2820                 return NULL;
2821         }
2822         fsm_newstate(privptr->fsm, DEV_STATE_STOPPED);
2823         fsm_settimer(privptr->fsm, &privptr->restart_timer);
2824         if (dev->mtu == 0)
2825                 dev->mtu = CTC_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
2826         dev->hard_start_xmit = ctc_tx;
2827         dev->open = ctc_open;
2828         dev->stop = ctc_close;
2829         dev->get_stats = ctc_stats;
2830         dev->change_mtu = ctc_change_mtu;
2831         dev->hard_header_len = LL_HEADER_LENGTH + 2;
2832         dev->addr_len = 0;
2833         dev->type = ARPHRD_SLIP;
2834         dev->tx_queue_len = 100;
2835         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
2836         SET_MODULE_OWNER(dev);
2837         return dev;
2838 }
2839
2840
2841 /**
2842  *
2843  * Setup an interface.
2844  *
2845  * @param cgdev  Device to be setup.
2846  *
2847  * @returns 0 on success, !0 on failure.
2848  */
2849 static int
2850 ctc_new_device(struct ccwgroup_device *cgdev)
2851 {
2852         char read_id[CTC_ID_SIZE];
2853         char write_id[CTC_ID_SIZE];
2854         int direction;
2855         enum channel_types type;
2856         struct ctc_priv *privptr;
2857         struct net_device *dev;
2858         int ret;
2859         char buffer[16];
2860
2861         pr_debug("%s() called\n", __FUNCTION__);
2862         DBF_TEXT(setup, 3, __FUNCTION__);
2863
2864         privptr = cgdev->dev.driver_data;
2865         if (!privptr)
2866                 return -ENODEV;
2867
2868         sprintf(buffer, "%d", privptr->buffer_size);
2869         DBF_TEXT(setup, 3, buffer);
2870
2871         type = get_channel_type(&cgdev->cdev[0]->id);
2872
2873         snprintf(read_id, CTC_ID_SIZE, "ch-%s", cgdev->cdev[0]->dev.bus_id);
2874         snprintf(write_id, CTC_ID_SIZE, "ch-%s", cgdev->cdev[1]->dev.bus_id);
2875
2876         if (add_channel(cgdev->cdev[0], type))
2877                 return -ENOMEM;
2878         if (add_channel(cgdev->cdev[1], type))
2879                 return -ENOMEM;
2880
2881         ret = ccw_device_set_online(cgdev->cdev[0]);
2882         if (ret != 0) {
2883                         printk(KERN_WARNING
2884                         "ccw_device_set_online (cdev[0]) failed with ret = %d\n", ret);
2885         }
2886
2887         ret = ccw_device_set_online(cgdev->cdev[1]);
2888         if (ret != 0) {
2889                         printk(KERN_WARNING
2890                         "ccw_device_set_online (cdev[1]) failed with ret = %d\n", ret);
2891         }
2892
2893         dev = ctc_init_netdevice(NULL, 1, privptr);
2894
2895         if (!dev) {
2896                 ctc_pr_warn("ctc_init_netdevice failed\n");
2897                 goto out;
2898         }
2899
2900         if (privptr->protocol == CTC_PROTO_LINUX_TTY)
2901                 strlcpy(dev->name, "ctctty%d", IFNAMSIZ);
2902         else
2903                 strlcpy(dev->name, "ctc%d", IFNAMSIZ);
2904
2905         for (direction = READ; direction <= WRITE; direction++) {
2906                 privptr->channel[direction] =
2907                     channel_get(type, direction == READ ? read_id : write_id,
2908                                 direction);
2909                 if (privptr->channel[direction] == NULL) {
2910                         if (direction == WRITE)
2911                                 channel_free(privptr->channel[READ]);
2912
2913                         ctc_free_netdevice(dev, 1);
2914                         goto out;
2915                 }
2916                 privptr->channel[direction]->netdev = dev;
2917                 privptr->channel[direction]->protocol = privptr->protocol;
2918                 privptr->channel[direction]->max_bufsize = privptr->buffer_size;
2919         }
2920         /* sysfs magic */
2921         SET_NETDEV_DEV(dev, &cgdev->dev);
2922
2923         if (ctc_netdev_register(dev) != 0) {
2924                 ctc_free_netdevice(dev, 1);
2925                 goto out;
2926         }
2927
2928         ctc_add_attributes(&cgdev->dev);
2929
2930         strlcpy(privptr->fsm->name, dev->name, sizeof (privptr->fsm->name));
2931
2932         print_banner();
2933
2934         ctc_pr_info("%s: read: %s, write: %s, proto: %d\n",
2935                     dev->name, privptr->channel[READ]->id,
2936                     privptr->channel[WRITE]->id, privptr->protocol);
2937
2938         return 0;
2939 out:
2940         ccw_device_set_offline(cgdev->cdev[1]);
2941         ccw_device_set_offline(cgdev->cdev[0]);
2942
2943         return -ENODEV;
2944 }
2945
2946 /**
2947  * Shutdown an interface.
2948  *
2949  * @param cgdev  Device to be shut down.
2950  *
2951  * @returns 0 on success, !0 on failure.
2952  */
2953 static int
2954 ctc_shutdown_device(struct ccwgroup_device *cgdev)
2955 {
2956         struct ctc_priv *priv;
2957         struct net_device *ndev;
2958
2959         DBF_TEXT(setup, 3, __FUNCTION__);
2960         pr_debug("%s() called\n", __FUNCTION__);
2961
2962
2963         priv = cgdev->dev.driver_data;
2964         ndev = NULL;
2965         if (!priv)
2966                 return -ENODEV;
2967
2968         if (priv->channel[READ]) {
2969                 ndev = priv->channel[READ]->netdev;
2970
2971                 /* Close the device */
2972                 ctc_close(ndev);
2973                 ndev->flags &=~IFF_RUNNING;
2974
2975                 ctc_remove_attributes(&cgdev->dev);
2976
2977                 channel_free(priv->channel[READ]);
2978         }
2979         if (priv->channel[WRITE])
2980                 channel_free(priv->channel[WRITE]);
2981
2982         if (ndev) {
2983                 ctc_netdev_unregister(ndev);
2984                 ndev->priv = NULL;
2985                 ctc_free_netdevice(ndev, 1);
2986         }
2987
2988         if (priv->fsm)
2989                 kfree_fsm(priv->fsm);
2990
2991         ccw_device_set_offline(cgdev->cdev[1]);
2992         ccw_device_set_offline(cgdev->cdev[0]);
2993
2994         if (priv->channel[READ])
2995                 channel_remove(priv->channel[READ]);
2996         if (priv->channel[WRITE])
2997                 channel_remove(priv->channel[WRITE]);
2998         priv->channel[READ] = priv->channel[WRITE] = NULL;
2999
3000         return 0;
3001
3002 }
3003
3004 static void
3005 ctc_remove_device(struct ccwgroup_device *cgdev)
3006 {
3007         struct ctc_priv *priv;
3008
3009         pr_debug("%s() called\n", __FUNCTION__);
3010         DBF_TEXT(setup, 3, __FUNCTION__);
3011
3012         priv = cgdev->dev.driver_data;
3013         if (!priv)
3014                 return;
3015         if (cgdev->state == CCWGROUP_ONLINE)
3016                 ctc_shutdown_device(cgdev);
3017         ctc_remove_files(&cgdev->dev);
3018         cgdev->dev.driver_data = NULL;
3019         kfree(priv);
3020         put_device(&cgdev->dev);
3021 }
3022
3023 static struct ccwgroup_driver ctc_group_driver = {
3024         .owner       = THIS_MODULE,
3025         .name        = "ctc",
3026         .max_slaves  = 2,
3027         .driver_id   = 0xC3E3C3,
3028         .probe       = ctc_probe_device,
3029         .remove      = ctc_remove_device,
3030         .set_online  = ctc_new_device,
3031         .set_offline = ctc_shutdown_device,
3032 };
3033
3034 /**
3035  * Module related routines
3036  *****************************************************************************/
3037
3038 /**
3039  * Prepare to be unloaded. Free IRQ's and release all resources.
3040  * This is called just before this module is unloaded. It is
3041  * <em>not</em> called, if the usage count is !0, so we don't need to check
3042  * for that.
3043  */
3044 static void __exit
3045 ctc_exit(void)
3046 {
3047         DBF_TEXT(setup, 3, __FUNCTION__);
3048         unregister_cu3088_discipline(&ctc_group_driver);
3049         ctc_tty_cleanup();
3050         ctc_unregister_dbf_views();
3051         ctc_pr_info("CTC driver unloaded\n");
3052 }
3053
3054 /**
3055  * Initialize module.
3056  * This is called just after the module is loaded.
3057  *
3058  * @return 0 on success, !0 on error.
3059  */
3060 static int __init
3061 ctc_init(void)
3062 {
3063         int ret = 0;
3064
3065         loglevel = CTC_LOGLEVEL_DEFAULT;
3066
3067         DBF_TEXT(setup, 3, __FUNCTION__);
3068
3069         print_banner();
3070
3071         ret = ctc_register_dbf_views();
3072         if (ret){
3073                 ctc_pr_crit("ctc_init failed with ctc_register_dbf_views rc = %d\n", ret);
3074                 return ret;
3075         }
3076         ctc_tty_init();
3077         ret = register_cu3088_discipline(&ctc_group_driver);
3078         if (ret) {
3079                 ctc_tty_cleanup();
3080                 ctc_unregister_dbf_views();
3081         }
3082         return ret;
3083 }
3084
3085 module_init(ctc_init);
3086 module_exit(ctc_exit);
3087
3088 /* --- This is the END my friend --- */