drivers/scsi/hosts.c

   1 /*
   2  *  hosts.c Copyright (C) 1992 Drew Eckhardt
   3  *          Copyright (C) 1993, 1994, 1995 Eric Youngdale
   4  *
   5  *  mid to lowlevel SCSI driver interface
   6  *      Initial versions: Drew Eckhardt
   7  *      Subsequent revisions: Eric Youngdale
   8  *
   9  *  <drew@colorado.edu>
  10  *
  11  *  Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
  12  */
  13
  14
  15 /*
  16  *  This file contains the medium level SCSI
  17  *  host interface initialization, as well as the scsi_hosts array of SCSI
  18  *  hosts currently present in the system.
  19  */
  20
  21 #define __NO_VERSION__
  22 #include <linux/module.h>
  23
  24 #include <linux/config.h>
  25 #include <linux/blk.h>
  26 #include <linux/kernel.h>
  27 #include <linux/string.h>
  28 #include <linux/mm.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/init.h>
  31
  32 #define __KERNEL_SYSCALLS__
  33
  34 #include <linux/unistd.h>
  35
  36 #include "scsi.h"
  37
  38 #ifndef NULL
  39 #define NULL 0L
  40 #endif
  41
  42 #define HOSTS_C
  43
  44 #include "hosts.h"
  45
  46 #if defined(CONFIG_A4000T_SCSI) || \
  47     defined(CONFIG_WARPENGINE_SCSI) || \
  48     defined(CONFIG_A4091_SCSI) || \
  49     defined (CONFIG_GVP_TURBO_SCSI) || \
  50     defined (CONFIG_BLZ603EPLUS_SCSI)
  51 #define AMIGA7XXCONFIG
  52 #endif
  53
  54 #ifdef AMIGA7XXCONFIG
  55 #include "amiga7xx.h"
  56 #endif
  57
  58 #ifdef CONFIG_MVME16x_SCSI
  59 #include "mvme16x.h"
  60 #endif
  61
  62 #ifdef CONFIG_BVME6000_SCSI
  63 #include "bvme6000.h"
  64 #endif
  65
  66 #ifdef CONFIG_A3000_SCSI
  67 #include "a3000.h"
  68 #endif
  69
  70 #ifdef CONFIG_A2091_SCSI
  71 #include "a2091.h"
  72 #endif
  73
  74 #ifdef CONFIG_GVP11_SCSI
  75 #include "gvp11.h"
  76 #endif
  77
  78 #ifdef CONFIG_CYBERSTORM_SCSI
  79 #include "cyberstorm.h"
  80 #endif
  81
  82 #ifdef CONFIG_CYBERSTORMII_SCSI
  83 #include "cyberstormII.h"
  84 #endif
  85
  86 #ifdef CONFIG_BLZ2060_SCSI
  87 #include "blz2060.h"
  88 #endif
  89
  90 #ifdef CONFIG_BLZ1230_SCSI
  91 #include "blz1230.h"
  92 #endif
  93
  94 #ifdef CONFIG_FASTLANE_SCSI
  95 #include "fastlane.h"
  96 #endif
  97
  98 #ifdef CONFIG_OKTAGON_SCSI
  99 #include "oktagon_esp.h"
 100 #endif
 101
 102 #ifdef CONFIG_ATARI_SCSI
 103 #include "atari_scsi.h"
 104 #endif
 105
 106 #ifdef CONFIG_MAC_SCSI_OLD
 107 #include "mac_scsi.h"
 108 #endif
 109
 110 #ifdef CONFIG_MAC_SCSI
 111 #include "mac_scsinew.h"
 112 #endif
 113
 114 #ifdef CONFIG_SCSI_MAC_ESP
 115 #include "mac_esp.h"
 116 #endif
 117
 118 #ifdef CONFIG_SCSI_ADVANSYS
 119 #include "advansys.h"
 120 #endif
 121
 122 #ifdef CONFIG_SCSI_AHA152X
 123 #include "aha152x.h"
 124 #endif
 125
 126 #ifdef CONFIG_SCSI_AHA1542
 127 #include "aha1542.h"
 128 #endif
 129
 130 #ifdef CONFIG_SCSI_AHA1740
 131 #include "aha1740.h"
 132 #endif
 133
 134 #ifdef CONFIG_SCSI_AIC7XXX
 135 #include "aic7xxx.h"
 136 #endif
 137
 138 #ifdef CONFIG_SCSI_IPS
 139 #include "ips.h"
 140 #endif
 141
 142 #ifdef CONFIG_SCSI_BUSLOGIC
 143 #include "BusLogic.h"
 144 #endif
 145
 146 #ifdef CONFIG_SCSI_EATA_DMA
 147 #include "eata_dma.h"
 148 #endif
 149
 150 #ifdef CONFIG_SCSI_EATA_PIO
 151 #include "eata_pio.h"
 152 #endif
 153
 154 #ifdef CONFIG_SCSI_U14_34F
 155 #include "u14-34f.h"
 156 #endif
 157
 158 #ifdef CONFIG_SCSI_FD_MCS
 159 #include "fd_mcs.h"
 160 #endif
 161
 162 #ifdef CONFIG_SCSI_FUTURE_DOMAIN
 163 #include "fdomain.h"
 164 #endif
 165
 166 #ifdef CONFIG_SCSI_GENERIC_NCR5380
 167 #include "g_NCR5380.h"
 168 #endif
 169
 170 #ifdef CONFIG_SCSI_IN2000
 171 #include "in2000.h"
 172 #endif
 173
 174 #ifdef CONFIG_SCSI_PAS16
 175 #include "pas16.h"
 176 #endif
 177
 178 #ifdef CONFIG_SCSI_QLOGIC_FAS
 179 #include "qlogicfas.h"
 180 #endif
 181
 182 #ifdef CONFIG_SCSI_QLOGIC_ISP
 183 #include "qlogicisp.h"
 184 #endif
 185
 186 #ifdef CONFIG_SCSI_QLOGIC_FC
 187 #include "qlogicfc.h"
 188 #endif
 189
 190 #ifdef CONFIG_SCSI_SEAGATE
 191 #include "seagate.h"
 192 #endif
 193
 194 #ifdef CONFIG_SCSI_T128
 195 #include "t128.h"
 196 #endif
 197
 198 #ifdef CONFIG_SCSI_DTC3280
 199 #include "dtc.h"
 200 #endif
 201
 202 #ifdef CONFIG_SCSI_NCR53C7xx
 203 #include "53c7,8xx.h"
 204 #endif
 205
 206 #ifdef CONFIG_SCSI_SYM53C8XX
 207 #include "sym53c8xx.h"
 208 #endif
 209
 210 #ifdef CONFIG_SCSI_NCR53C8XX
 211 #include "ncr53c8xx.h"
 212 #endif
 213
 214 #ifdef CONFIG_SCSI_ULTRASTOR
 215 #include "ultrastor.h"
 216 #endif
 217
 218 #ifdef CONFIG_SCSI_7000FASST
 219 #include "wd7000.h"
 220 #endif
 221
 222 #ifdef CONFIG_SCSI_MCA_53C9X
 223 #include "mca_53c9x.h"
 224 #endif
 225
 226 #ifdef CONFIG_SCSI_IBMMCA
 227 #include "ibmmca.h"
 228 #endif
 229
 230 #ifdef CONFIG_SCSI_EATA
 231 #include "eata.h"
 232 #endif
 233
 234 #ifdef CONFIG_SCSI_NCR53C406A
 235 #include "NCR53c406a.h"
 236 #endif
 237
 238 #ifdef CONFIG_SCSI_SYM53C416
 239 #include "sym53c416.h"
 240 #endif
 241
 242 #ifdef CONFIG_SCSI_DC390T
 243 #include "dc390.h"
 244 #endif
 245
 246 #ifdef CONFIG_SCSI_AM53C974
 247 #include "AM53C974.h"
 248 #endif
 249
 250 #ifdef CONFIG_SCSI_MEGARAID
 251 #include "megaraid.h"
 252 #endif
 253
 254 #ifdef CONFIG_SCSI_ACARD
 255 #include "atp870u.h"
 256 #endif
 257
 258 #ifdef CONFIG_SCSI_SUNESP
 259 #include "esp.h"
 260 #endif
 261
 262 #ifdef CONFIG_SCSI_QLOGICPTI
 263 #include "qlogicpti.h"
 264 #endif
 265
 266 #ifdef CONFIG_BLK_DEV_IDESCSI
 267 #include "ide-scsi.h"
 268 #endif
 269
 270 #ifdef CONFIG_SCSI_MESH
 271 #include "mesh.h"
 272 #endif
 273
 274 #ifdef CONFIG_SCSI_MAC53C94
 275 #include "mac53c94.h"
 276 #endif
 277
 278 #ifdef CONFIG_SCSI_GDTH
 279 #include "gdth.h"
 280 #endif
 281
 282 #ifdef CONFIG_SCSI_PCI2000
 283 #include "pci2000.h"
 284 #endif
 285
 286 #ifdef CONFIG_SCSI_PCI2220I
 287 #include "pci2220i.h"
 288 #endif
 289
 290 #ifdef CONFIG_SCSI_PSI240I
 291 #include "psi240i.h"
 292 #endif
 293
 294 #ifdef CONFIG_SCSI_PLUTO
 295 #include "pluto.h"
 296 #endif
 297
 298 #ifdef CONFIG_SCSI_INITIO
 299 #include "ini9100u.h"
 300 #endif
 301
 302 #ifdef CONFIG_SCSI_INIA100
 303 #include "inia100.h"
 304 #endif
 305
 306 #ifdef CONFIG_SCSI_DEBUG
 307 #include "scsi_debug.h"
 308 #endif
 309
 310 #ifdef CONFIG_SCSI_ACORNSCSI_3
 311 #include "../acorn/scsi/acornscsi.h"
 312 #endif
 313
 314 #ifdef CONFIG_SCSI_CUMANA_1
 315 #include "../acorn/scsi/cumana_1.h"
 316 #endif
 317
 318 #ifdef CONFIG_SCSI_CUMANA_2
 319 #include "../acorn/scsi/cumana_2.h"
 320 #endif
 321
 322 #ifdef CONFIG_SCSI_ECOSCSI
 323 #include "../acorn/scsi/ecoscsi.h"
 324 #endif
 325
 326 #ifdef CONFIG_SCSI_OAK1
 327 #include "../acorn/scsi/oak.h"
 328 #endif
 329
 330 #ifdef CONFIG_SCSI_POWERTECSCSI
 331 #include "../acorn/scsi/powertec.h"
 332 #endif
 333
 334 #ifdef CONFIG_JAZZ_ESP
 335 #include "jazz_esp.h"
 336 #endif
 337
 338 #ifdef CONFIG_SUN3X_ESP
 339 #include "sun3x_esp.h"
 340 #endif
 341
 342 #ifdef CONFIG_IPHASE5526
 343 #include "../net/fc/iph5526_scsi.h"
 344 #endif
 345
 346 /*
 347  * Moved ppa driver to the end of the probe list
 348  * since it is a removable host adapter.
 349  * This means the parallel ZIP drive will not bump
 350  * the order of the /dev/sd devices - campbell@torque.net
 351  */
 352 #ifdef CONFIG_SCSI_PPA
 353 #include "ppa.h"
 354 #endif
 355
 356 #ifdef CONFIG_SCSI_IMM
 357 #include "imm.h"
 358 #endif
 359
 360 /*
 361 static const char RCSid[] = "$Header: /vger/u4/cvs/linux/drivers/scsi/hosts.c,v 1.20 1996/12/12 19:18:32 davem Exp $";
 362 */
 363
 364 /*
 365  *  The scsi host entries should be in the order you wish the
 366  *  cards to be detected.  A driver may appear more than once IFF
 367  *  it can deal with being detected (and therefore initialized)
 368  *  with more than one simultaneous host number, can handle being
 369  *  reentrant, etc.
 370  *
 371  *  They may appear in any order, as each SCSI host is told which host
 372  *  number it is during detection.
 373  */
 374
 375 /* This is a placeholder for controllers that are not configured into
 376  * the system - we do this to ensure that the controller numbering is
 377  * always consistent, no matter how the kernel is configured. */
 378
 379 #define NO_CONTROLLER {NULL, NULL, NULL, NULL, NULL, NULL, NULL, \
 380                            NULL, NULL, 0, 0, 0, 0, 0, 0}
 381
 382 /*
 383  *  When figure is run, we don't want to link to any object code.  Since
 384  *  the macro for each host will contain function pointers, we cannot
 385  *  use it and instead must use a "blank" that does no such
 386  *  idiocy.
 387  */
 388
 389 Scsi_Host_Template * scsi_hosts = NULL;
 390
 391 static Scsi_Host_Template builtin_scsi_hosts[] =
 392 {
 393 #ifdef CONFIG_AMIGA
 394 #ifdef AMIGA7XXCONFIG
 395         AMIGA7XX_SCSI,
 396 #endif
 397 #ifdef CONFIG_A3000_SCSI
 398         A3000_SCSI,
 399 #endif
 400 #ifdef CONFIG_A2091_SCSI
 401         A2091_SCSI,
 402 #endif
 403 #ifdef CONFIG_GVP11_SCSI
 404         GVP11_SCSI,
 405 #endif
 406 #ifdef CONFIG_CYBERSTORM_SCSI
 407         SCSI_CYBERSTORM,
 408 #endif
 409 #ifdef CONFIG_CYBERSTORMII_SCSI
 410         SCSI_CYBERSTORMII,
 411 #endif
 412 #ifdef CONFIG_BLZ2060_SCSI
 413         SCSI_BLZ2060,
 414 #endif
 415 #ifdef CONFIG_BLZ1230_SCSI
 416         SCSI_BLZ1230,
 417 #endif
 418 #ifdef CONFIG_FASTLANE_SCSI
 419         SCSI_FASTLANE,
 420 #endif
 421 #ifdef CONFIG_OKTAGON_SCSI
 422         SCSI_OKTAGON_ESP,
 423 #endif
 424 #endif
 425
 426 #ifdef CONFIG_ATARI
 427 #ifdef CONFIG_ATARI_SCSI
 428         ATARI_SCSI,
 429 #endif
 430 #endif
 431
 432 #ifdef CONFIG_MAC
 433 #ifdef CONFIG_MAC_SCSI_OLD
 434         MAC_SCSI,
 435 #endif
 436 #ifdef CONFIG_SCSI_MAC_ESP
 437         SCSI_MAC_ESP,
 438 #endif
 439 #ifdef CONFIG_MAC_SCSI
 440         MAC_NCR5380,
 441 #endif
 442 #endif
 443
 444 #ifdef CONFIG_MVME16x_SCSI
 445         MVME16x_SCSI,
 446 #endif
 447 #ifdef CONFIG_BVME6000_SCSI
 448         BVME6000_SCSI,
 449 #endif
 450 #ifdef CONFIG_SCSI_ADVANSYS
 451         ADVANSYS,
 452 #endif
 453
 454 #ifdef CONFIG_SCSI_PCI2000
 455         PCI2000,
 456 #endif
 457 #ifdef CONFIG_SCSI_PCI2220I
 458         PCI2220I,
 459 #endif
 460 #ifdef CONFIG_SCSI_PSI240I
 461         PSI240I,
 462 #endif
 463
 464 /* BusLogic must come before aha1542.c */
 465 #ifdef CONFIG_SCSI_BUSLOGIC
 466     BUSLOGIC,
 467 #endif
 468 #ifdef CONFIG_SCSI_U14_34F
 469     ULTRASTOR_14_34F,
 470 #endif
 471 #ifdef CONFIG_SCSI_ULTRASTOR
 472     ULTRASTOR_14F,
 473 #endif
 474 #ifdef CONFIG_SCSI_AHA152X
 475     AHA152X,
 476 #endif
 477 #ifdef CONFIG_SCSI_AHA1542
 478     AHA1542,
 479 #endif
 480 #ifdef CONFIG_SCSI_AHA1740
 481     AHA1740,
 482 #endif
 483 #ifdef CONFIG_SCSI_AIC7XXX
 484     AIC7XXX,
 485 #endif
 486 #ifdef CONFIG_SCSI_IPS
 487     IPS,
 488 #endif
 489 #ifdef CONFIG_SCSI_FD_MCS
 490    FD_MCS,
 491 #endif
 492 #ifdef CONFIG_SCSI_FUTURE_DOMAIN
 493     FDOMAIN_16X0,
 494 #endif
 495 #ifdef CONFIG_SCSI_IN2000
 496     IN2000,
 497 #endif
 498 #ifdef CONFIG_SCSI_GENERIC_NCR5380
 499     GENERIC_NCR5380,
 500 #endif
 501 #ifdef CONFIG_SCSI_NCR53C406A   /* 53C406A should come before QLOGIC */
 502     NCR53c406a,
 503 #endif
 504 #ifdef CONFIG_SCSI_SYM53C416
 505     SYM53C416,
 506 #endif
 507 #ifdef CONFIG_SCSI_QLOGIC_FAS
 508     QLOGICFAS,
 509 #endif
 510 #ifdef CONFIG_SCSI_QLOGIC_ISP
 511     QLOGICISP,
 512 #endif
 513 #ifdef CONFIG_SCSI_QLOGIC_FC
 514     QLOGICFC,
 515 #endif
 516 #ifdef CONFIG_SCSI_PAS16
 517     MV_PAS16,
 518 #endif
 519 #ifdef CONFIG_SCSI_SEAGATE
 520     SEAGATE_ST0X,
 521 #endif
 522 #ifdef CONFIG_SCSI_T128
 523     TRANTOR_T128,
 524 #endif
 525 #ifdef CONFIG_SCSI_DTC3280
 526         DTC3x80,
 527 #endif
 528 #ifdef CONFIG_SCSI_NCR53C7xx
 529     NCR53c7xx,
 530 #endif
 531 #ifdef CONFIG_SCSI_SYM53C8XX
 532     SYM53C8XX,
 533 #endif
 534 #ifdef CONFIG_SCSI_NCR53C8XX
 535     NCR53C8XX,
 536 #endif
 537 #ifdef CONFIG_SCSI_EATA_DMA
 538     EATA_DMA,
 539 #endif
 540 #ifdef CONFIG_SCSI_EATA_PIO
 541     EATA_PIO,
 542 #endif
 543 #ifdef CONFIG_SCSI_7000FASST
 544     WD7000,
 545 #endif
 546 #ifdef CONFIG_SCSI_MCA_53C9X
 547     MCA_53C9X,
 548 #endif
 549 #ifdef CONFIG_SCSI_IBMMCA
 550     IBMMCA,
 551 #endif
 552 #ifdef CONFIG_SCSI_EATA
 553     EATA,
 554 #endif
 555 #ifdef CONFIG_SCSI_DC390T
 556     DC390_T,
 557 #endif
 558 #ifdef CONFIG_SCSI_AM53C974
 559     AM53C974,
 560 #endif
 561 #ifdef CONFIG_SCSI_MEGARAID
 562     MEGARAID,
 563 #endif
 564 #ifdef CONFIG_SCSI_ACARD
 565     ATP870U,
 566 #endif
 567 #ifdef CONFIG_SCSI_SUNESP
 568     SCSI_SPARC_ESP,
 569 #endif
 570 #ifdef CONFIG_SCSI_GDTH
 571     GDTH,
 572 #endif
 573 #ifdef CONFIG_SCSI_INITIO
 574     INI9100U,
 575 #endif
 576 #ifdef CONFIG_SCSI_INIA100
 577     INIA100,
 578 #endif
 579 #ifdef CONFIG_SCSI_QLOGICPTI
 580     QLOGICPTI,
 581 #endif
 582 #ifdef CONFIG_BLK_DEV_IDESCSI
 583     IDESCSI,
 584 #endif
 585 #ifdef CONFIG_SCSI_MESH
 586     SCSI_MESH,
 587 #endif
 588 #ifdef CONFIG_SCSI_MAC53C94
 589     SCSI_MAC53C94,
 590 #endif
 591 #ifdef CONFIG_SCSI_PLUTO
 592     PLUTO,
 593 #endif
 594 #ifdef CONFIG_ARCH_ACORN
 595 #ifdef CONFIG_SCSI_ACORNSCSI_3
 596     ACORNSCSI_3,
 597 #endif
 598 #ifdef CONFIG_SCSI_CUMANA_1
 599     CUMANA_NCR5380,
 600 #endif
 601 #ifdef CONFIG_SCSI_CUMANA_2
 602     CUMANA_FAS216,
 603 #endif
 604 #ifdef CONFIG_SCSI_ECOSCSI
 605     ECOSCSI_NCR5380,
 606 #endif
 607 #ifdef CONFIG_SCSI_OAK1
 608     OAK_NCR5380,
 609 #endif
 610 #ifdef CONFIG_SCSI_POWERTECSCSI
 611     POWERTECSCSI,
 612 #endif
 613 #endif
 614 #ifdef CONFIG_IPHASE5526
 615         IPH5526_SCSI_FC,
 616 #endif
 617 /* "Removable host adapters" below this line (Parallel Port/USB/other) */
 618 #ifdef CONFIG_SCSI_PPA
 619     PPA,
 620 #endif
 621 #ifdef CONFIG_SCSI_IMM
 622     IMM,
 623 #endif
 624 #ifdef CONFIG_SUN3X_ESP
 625     SCSI_SUN3X_ESP,
 626 #endif
 627 #ifdef CONFIG_SCSI_DEBUG
 628     SCSI_DEBUG,
 629 #endif
 630 };
 631
 632 #define MAX_SCSI_HOSTS (sizeof(builtin_scsi_hosts) / sizeof(Scsi_Host_Template))
 633
 634
 635 /*
 636  *  Our semaphores and timeout counters, where size depends on
 637  *      MAX_SCSI_HOSTS here.
 638  */
 639
 640 struct Scsi_Host * scsi_hostlist = NULL;
 641 struct Scsi_Device_Template * scsi_devicelist = NULL;
 642
 643 int max_scsi_hosts = 0;
 644 int next_scsi_host = 0;
 645
 646 void
 647 scsi_unregister(struct Scsi_Host * sh){
 648     struct Scsi_Host * shpnt;
 649
 650     if(scsi_hostlist == sh)
 651         scsi_hostlist = sh->next;
 652     else {
 653         shpnt = scsi_hostlist;
 654         while(shpnt->next != sh) shpnt = shpnt->next;
 655         shpnt->next = shpnt->next->next;
 656     }
 657
 658     /* If we are removing the last host registered, it is safe to reuse
 659      * its host number (this avoids "holes" at boot time) (DB)
 660      * It is also safe to reuse those of numbers directly below which have
 661      * been released earlier (to avoid some holes in numbering).
 662      */
 663     if(sh->host_no == max_scsi_hosts - 1) {
 664         while(--max_scsi_hosts >= next_scsi_host) {
 665             shpnt = scsi_hostlist;
 666             while(shpnt && shpnt->host_no != max_scsi_hosts - 1)
 667                 shpnt = shpnt->next;
 668             if(shpnt)
 669                 break;
 670         }
 671     }
 672     next_scsi_host--;
 673     scsi_init_free((char *) sh, sizeof(struct Scsi_Host) + sh->extra_bytes);
 674 }
 675
 676 /* We call this when we come across a new host adapter. We only do this
 677  * once we are 100% sure that we want to use this host adapter -  it is a
 678  * pain to reverse this, so we try to avoid it
 679  */
 680
 681 struct Scsi_Host * scsi_register(Scsi_Host_Template * tpnt, int j){
 682     struct Scsi_Host * retval, *shpnt;
 683     retval = (struct Scsi_Host *)scsi_init_malloc(sizeof(struct Scsi_Host) + j,
 684                                                   (tpnt->unchecked_isa_dma && j ? GFP_DMA : 0) | GFP_ATOMIC);
 685     atomic_set(&retval->host_active,0);
 686     retval->host_busy = 0;
 687     retval->host_failed = 0;
 688     retval->block = NULL;
 689     retval->wish_block = 0;
 690     if(j > 0xffff) panic("Too many extra bytes requested\n");
 691     retval->extra_bytes = j;
 692     retval->loaded_as_module = scsi_loadable_module_flag;
 693     retval->host_no = max_scsi_hosts++; /* never reuse host_no (DB) */
 694     next_scsi_host++;
 695     retval->host_queue = NULL;
 696     init_waitqueue_head(&retval->host_wait);
 697     retval->resetting = 0;
 698     retval->last_reset = 0;
 699     retval->irq = 0;
 700     retval->dma_channel = 0xff;
 701
 702     /* These three are default values which can be overridden */
 703     retval->max_channel = 0;
 704     retval->max_id = 8;
 705     retval->max_lun = 8;
 706
 707     retval->unique_id = 0;
 708     retval->io_port = 0;
 709     retval->hostt = tpnt;
 710     retval->next = NULL;
 711     retval->in_recovery = 0;
 712     retval->ehandler = NULL;    /* Initial value until the thing starts up. */
 713     retval->eh_notify   = NULL;    /* Who we notify when we exit. */
 714
 715     /*
 716      * Initialize the fields used for mid-level queueing.
 717      */
 718     retval->pending_commands = NULL;
 719     retval->host_busy = FALSE;
 720
 721 #ifdef DEBUG
 722     printk("Register %x %x: %d\n", (int)retval, (int)retval->hostt, j);
 723 #endif
 724
 725     /* The next six are the default values which can be overridden
 726      * if need be */
 727     retval->this_id = tpnt->this_id;
 728     retval->can_queue = tpnt->can_queue;
 729     retval->sg_tablesize = tpnt->sg_tablesize;
 730     retval->cmd_per_lun = tpnt->cmd_per_lun;
 731     retval->unchecked_isa_dma = tpnt->unchecked_isa_dma;
 732     retval->use_clustering = tpnt->use_clustering;
 733
 734     retval->select_queue_depths = NULL;
 735
 736     if(!scsi_hostlist)
 737         scsi_hostlist = retval;
 738     else
 739     {
 740         shpnt = scsi_hostlist;
 741         while(shpnt->next) shpnt = shpnt->next;
 742         shpnt->next = retval;
 743     }
 744
 745     return retval;
 746 }
 747
 748 int
 749 scsi_register_device(struct Scsi_Device_Template * sdpnt)
 750 {
 751     if(sdpnt->next) panic("Device already registered");
 752     sdpnt->next = scsi_devicelist;
 753     scsi_devicelist = sdpnt;
 754     return 0;
 755 }
 756
 757 /*
 758  * Why is this a separate function?  Because the kernel_thread code
 759  * effectively does a fork, and there is a builtin exit() call when
 760  * the child returns.   The difficulty is that scsi_init() is
 761  * marked __init, which means the memory is unmapped after bootup
 762  * is complete, which means that the thread's exit() call gets wiped.
 763  *
 764  * The lesson is to *NEVER*, *NEVER* call kernel_thread() from an
 765  * __init function, if that function could ever return.
 766  */
 767 static void launch_error_handler_thread(struct Scsi_Host * shpnt)
 768 {
 769             DECLARE_MUTEX_LOCKED(sem);
 770
 771             shpnt->eh_notify = &sem;
 772
 773             kernel_thread((int (*)(void *))scsi_error_handler,
 774                           (void *) shpnt, 0);
 775             /*
 776              * Now wait for the kernel error thread to initialize itself
 777              * as it might be needed when we scan the bus.
 778              */
 779             down (&sem);
 780             shpnt->eh_notify = NULL;
 781 }
 782
 783 unsigned int __init scsi_init(void)
 784 {
 785     static int called = 0;
 786     int i, pcount;
 787     unsigned long flags;
 788     Scsi_Host_Template * tpnt;
 789     struct Scsi_Host * shpnt;
 790     const char * name;
 791
 792     if(called) return 0;
 793
 794     called = 1;
 795     for (tpnt = &builtin_scsi_hosts[0], i = 0; i < MAX_SCSI_HOSTS; ++i, tpnt++)
 796     {
 797         /*
 798          * Initialize our semaphores.  -1 is interpreted to mean
 799          * "inactive" - where as 0 will indicate a time out condition.
 800          */
 801
 802         pcount = next_scsi_host;
 803         if (tpnt->detect) {
 804
 805            /* The detect routine must carefully spinunlock/spinlock if
 806               it enables interrupts, since all interrupt handlers do
 807               spinlock as well.
 808               All lame drivers are going to fail due to the following
 809               spinlock. For the time beeing let's use it only for drivers
 810               using the new scsi code. NOTE: the detect routine could
 811               redefine the value tpnt->use_new_eh_code. (DB, 13 May 1998) */
 812
 813            if (tpnt->use_new_eh_code) {
 814               spin_lock_irqsave(&io_request_lock, flags);
 815               tpnt->present = tpnt->detect(tpnt);
 816               spin_unlock_irqrestore(&io_request_lock, flags);
 817               }
 818            else
 819               tpnt->present = tpnt->detect(tpnt);
 820
 821            }
 822
 823         if (tpnt->detect && tpnt->present)
 824         {
 825             /* The only time this should come up is when people use
 826              * some kind of patched driver of some kind or another. */
 827             if(pcount == next_scsi_host) {
 828                 if(tpnt->present > 1)
 829                     panic("Failure to register low-level scsi driver");
 830                 /* The low-level driver failed to register a driver.  We
 831                  * can do this now. */
 832                 scsi_register(tpnt,0);
 833             }
 834             tpnt->next = scsi_hosts;
 835             scsi_hosts = tpnt;
 836
 837             /* Add the driver to /proc/scsi */
 838 #if CONFIG_PROC_FS
 839             build_proc_dir_entries(tpnt);
 840 #endif
 841         }
 842     }
 843
 844     for(shpnt=scsi_hostlist; shpnt; shpnt = shpnt->next)
 845     {
 846         if(shpnt->hostt->info)
 847             name = shpnt->hostt->info(shpnt);
 848         else
 849             name = shpnt->hostt->name;
 850         printk ("scsi%d : %s\n", /* And print a little message */
 851                 shpnt->host_no, name);
 852
 853         /*
 854          * Now start the error recovery thread for the host.
 855          */
 856         if( shpnt->hostt->use_new_eh_code )
 857         {
 858             launch_error_handler_thread(shpnt);
 859         }
 860     }
 861
 862     printk ("scsi : %d host%s.\n", next_scsi_host,
 863             (next_scsi_host == 1) ? "" : "s");
 864
 865     scsi_make_blocked_list();
 866
 867     /* Now attach the high level drivers */
 868 #ifdef CONFIG_BLK_DEV_SD
 869     scsi_register_device(&sd_template);
 870 #endif
 871 #ifdef CONFIG_BLK_DEV_SR
 872     scsi_register_device(&sr_template);
 873 #endif
 874 #ifdef CONFIG_CHR_DEV_ST
 875     scsi_register_device(&st_template);
 876 #endif
 877 #ifdef CONFIG_CHR_DEV_SG
 878     scsi_register_device(&sg_template);
 879 #endif
 880
 881 #if 0
 882     max_scsi_hosts = next_scsi_host;
 883 #endif
 884     return 0;
 885 }
 886
 887 /*
 888  * Overrides for Emacs so that we follow Linus's tabbing style.
 889  * Emacs will notice this stuff at the end of the file and automatically
 890  * adjust the settings for this buffer only.  This must remain at the end
 891  * of the file.
 892  * ---------------------------------------------------------------------------
 893  * Local variables:
 894  * c-indent-level: 4
 895  * c-brace-imaginary-offset: 0
 896  * c-brace-offset: -4
 897  * c-argdecl-indent: 4
 898  * c-label-offset: -4
 899  * c-continued-statement-offset: 4
 900  * c-continued-brace-offset: 0
 901  * indent-tabs-mode: nil
 902  * tab-width: 8
 903  * End:
 904  */