drivers/scsi/device_handler/scsi_dh_emc.c

   1 /*
   2  * Target driver for EMC CLARiiON AX/CX-series hardware.
   3  * Based on code from Lars Marowsky-Bree <lmb@suse.de>
   4  * and Ed Goggin <egoggin@emc.com>.
   5  *
   6  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   7  * Copyright (C) 2006 Mike Christie
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2, or (at your option)
  12  * any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; see the file COPYING.  If not, write to
  21  * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23 #include <linux/slab.h>
  24 #include <scsi/scsi.h>
  25 #include <scsi/scsi_eh.h>
  26 #include <scsi/scsi_dh.h>
  27 #include <scsi/scsi_device.h>
  28
  29 #define CLARIION_NAME                   "emc"
  30
  31 #define CLARIION_TRESPASS_PAGE          0x22
  32 #define CLARIION_BUFFER_SIZE            0xFC
  33 #define CLARIION_TIMEOUT                (60 * HZ)
  34 #define CLARIION_RETRIES                3
  35 #define CLARIION_UNBOUND_LU             -1
  36 #define CLARIION_SP_A                   0
  37 #define CLARIION_SP_B                   1
  38
  39 /* Flags */
  40 #define CLARIION_SHORT_TRESPASS         1
  41 #define CLARIION_HONOR_RESERVATIONS     2
  42
  43 /* LUN states */
  44 #define CLARIION_LUN_UNINITIALIZED      -1
  45 #define CLARIION_LUN_UNBOUND            0
  46 #define CLARIION_LUN_BOUND              1
  47 #define CLARIION_LUN_OWNED              2
  48
  49 static unsigned char long_trespass[] = {
  50         0, 0, 0, 0, 0, 0, 0, 0,
  51         CLARIION_TRESPASS_PAGE, /* Page code */
  52         0x09,                   /* Page length - 2 */
  53         0x01,                   /* Trespass code */
  54         0xff, 0xff,             /* Trespass target */
  55         0, 0, 0, 0, 0, 0        /* Reserved bytes / unknown */
  56 };
  57
  58 static unsigned char short_trespass[] = {
  59         0, 0, 0, 0,
  60         CLARIION_TRESPASS_PAGE, /* Page code */
  61         0x02,                   /* Page length - 2 */
  62         0x01,                   /* Trespass code */
  63         0xff,                   /* Trespass target */
  64 };
  65
  66 static const char * lun_state[] =
  67 {
  68     "not bound",
  69     "bound",
  70     "owned",
  71 };
  72
  73 struct clariion_dh_data {
  74         /*
  75          * Flags:
  76          *  CLARIION_SHORT_TRESPASS
  77          * Use short trespass command (FC-series) or the long version
  78          * (default for AX/CX CLARiiON arrays).
  79          *
  80          *  CLARIION_HONOR_RESERVATIONS
  81          * Whether or not (default) to honor SCSI reservations when
  82          * initiating a switch-over.
  83          */
  84         unsigned flags;
  85         /*
  86          * I/O buffer for both MODE_SELECT and INQUIRY commands.
  87          */
  88         unsigned char buffer[CLARIION_BUFFER_SIZE];
  89         /*
  90          * SCSI sense buffer for commands -- assumes serial issuance
  91          * and completion sequence of all commands for same multipath.
  92          */
  93         unsigned char sense[SCSI_SENSE_BUFFERSIZE];
  94         unsigned int senselen;
  95         /*
  96          * LUN state
  97          */
  98         int lun_state;
  99         /*
 100          * SP Port number
 101          */
 102         int port;
 103         /*
 104          * which SP (A=0,B=1,UNBOUND=-1) is the default SP for this
 105          * path's mapped LUN
 106          */
 107         int default_sp;
 108         /*
 109          * which SP (A=0,B=1,UNBOUND=-1) is the active SP for this
 110          * path's mapped LUN
 111          */
 112         int current_sp;
 113 };
 114
 115 static inline struct clariion_dh_data
 116                         *get_clariion_data(struct scsi_device *sdev)
 117 {
 118         struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
 119         BUG_ON(scsi_dh_data == NULL);
 120         return ((struct clariion_dh_data *) scsi_dh_data->buf);
 121 }
 122
 123 /*
 124  * Parse MODE_SELECT cmd reply.
 125  */
 126 static int trespass_endio(struct scsi_device *sdev, char *sense)
 127 {
 128         int err = SCSI_DH_IO;
 129         struct scsi_sense_hdr sshdr;
 130
 131         if (!scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)) {
 132                 sdev_printk(KERN_ERR, sdev, "%s: Found valid sense data 0x%2x, "
 133                             "0x%2x, 0x%2x while sending CLARiiON trespass "
 134                             "command.\n", CLARIION_NAME, sshdr.sense_key,
 135                             sshdr.asc, sshdr.ascq);
 136
 137                 if ((sshdr.sense_key == 0x05) && (sshdr.asc == 0x04) &&
 138                      (sshdr.ascq == 0x00)) {
 139                         /*
 140                          * Array based copy in progress -- do not send
 141                          * mode_select or copy will be aborted mid-stream.
 142                          */
 143                         sdev_printk(KERN_INFO, sdev, "%s: Array Based Copy in "
 144                                     "progress while sending CLARiiON trespass "
 145                                     "command.\n", CLARIION_NAME);
 146                         err = SCSI_DH_DEV_TEMP_BUSY;
 147                 } else if ((sshdr.sense_key == 0x02) && (sshdr.asc == 0x04) &&
 148                             (sshdr.ascq == 0x03)) {
 149                         /*
 150                          * LUN Not Ready - Manual Intervention Required
 151                          * indicates in-progress ucode upgrade (NDU).
 152                          */
 153                         sdev_printk(KERN_INFO, sdev, "%s: Detected in-progress "
 154                                     "ucode upgrade NDU operation while sending "
 155                                     "CLARiiON trespass command.\n", CLARIION_NAME);
 156                         err = SCSI_DH_DEV_TEMP_BUSY;
 157                 } else
 158                         err = SCSI_DH_DEV_FAILED;
 159         } else {
 160                 sdev_printk(KERN_INFO, sdev,
 161                             "%s: failed to send MODE SELECT, no sense available\n",
 162                             CLARIION_NAME);
 163         }
 164         return err;
 165 }
 166
 167 static int parse_sp_info_reply(struct scsi_device *sdev,
 168                                struct clariion_dh_data *csdev)
 169 {
 170         int err = SCSI_DH_OK;
 171
 172         /* check for in-progress ucode upgrade (NDU) */
 173         if (csdev->buffer[48] != 0) {
 174                 sdev_printk(KERN_NOTICE, sdev, "%s: Detected in-progress "
 175                             "ucode upgrade NDU operation while finding "
 176                             "current active SP.", CLARIION_NAME);
 177                 err = SCSI_DH_DEV_TEMP_BUSY;
 178                 goto out;
 179         }
 180         if (csdev->buffer[4] > 2) {
 181                 /* Invalid buffer format */
 182                 sdev_printk(KERN_NOTICE, sdev,
 183                             "%s: invalid VPD page 0xC0 format\n",
 184                             CLARIION_NAME);
 185                 err = SCSI_DH_NOSYS;
 186                 goto out;
 187         }
 188         switch (csdev->buffer[28] & 0x0f) {
 189         case 6:
 190                 sdev_printk(KERN_NOTICE, sdev,
 191                             "%s: ALUA failover mode detected\n",
 192                             CLARIION_NAME);
 193                 break;
 194         case 4:
 195                 /* Linux failover */
 196                 break;
 197         default:
 198                 sdev_printk(KERN_WARNING, sdev,
 199                             "%s: Invalid failover mode %d\n",
 200                             CLARIION_NAME, csdev->buffer[28] & 0x0f);
 201                 err = SCSI_DH_NOSYS;
 202                 goto out;
 203         }
 204
 205         csdev->default_sp = csdev->buffer[5];
 206         csdev->lun_state = csdev->buffer[4];
 207         csdev->current_sp = csdev->buffer[8];
 208         csdev->port = csdev->buffer[7];
 209
 210 out:
 211         return err;
 212 }
 213
 214 #define emc_default_str "FC (Legacy)"
 215
 216 static char * parse_sp_model(struct scsi_device *sdev, unsigned char *buffer)
 217 {
 218         unsigned char len = buffer[4] + 5;
 219         char *sp_model = NULL;
 220         unsigned char sp_len, serial_len;
 221
 222         if (len < 160) {
 223                 sdev_printk(KERN_WARNING, sdev,
 224                             "%s: Invalid information section length %d\n",
 225                             CLARIION_NAME, len);
 226                 /* Check for old FC arrays */
 227                 if (!strncmp(buffer + 8, "DGC", 3)) {
 228                         /* Old FC array, not supporting extended information */
 229                         sp_model = emc_default_str;
 230                 }
 231                 goto out;
 232         }
 233
 234         /*
 235          * Parse extended information for SP model number
 236          */
 237         serial_len = buffer[160];
 238         if (serial_len == 0 || serial_len + 161 > len) {
 239                 sdev_printk(KERN_WARNING, sdev,
 240                             "%s: Invalid array serial number length %d\n",
 241                             CLARIION_NAME, serial_len);
 242                 goto out;
 243         }
 244         sp_len = buffer[99];
 245         if (sp_len == 0 || serial_len + sp_len + 161 > len) {
 246                 sdev_printk(KERN_WARNING, sdev,
 247                             "%s: Invalid model number length %d\n",
 248                             CLARIION_NAME, sp_len);
 249                 goto out;
 250         }
 251         sp_model = &buffer[serial_len + 161];
 252         /* Strip whitespace at the end */
 253         while (sp_len > 1 && sp_model[sp_len - 1] == ' ')
 254                 sp_len--;
 255
 256         sp_model[sp_len] = '\0';
 257
 258 out:
 259         return sp_model;
 260 }
 261
 262 /*
 263  * Get block request for REQ_BLOCK_PC command issued to path.  Currently
 264  * limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
 265  *
 266  * Uses data and sense buffers in hardware handler context structure and
 267  * assumes serial servicing of commands, both issuance and completion.
 268  */
 269 static struct request *get_req(struct scsi_device *sdev, int cmd,
 270                                 unsigned char *buffer)
 271 {
 272         struct request *rq;
 273         int len = 0;
 274
 275         rq = blk_get_request(sdev->request_queue,
 276                         (cmd != INQUIRY) ? WRITE : READ, GFP_NOIO);
 277         if (!rq) {
 278                 sdev_printk(KERN_INFO, sdev, "get_req: blk_get_request failed");
 279                 return NULL;
 280         }
 281
 282         rq->cmd_len = COMMAND_SIZE(cmd);
 283         rq->cmd[0] = cmd;
 284
 285         switch (cmd) {
 286         case MODE_SELECT:
 287                 len = sizeof(short_trespass);
 288                 rq->cmd_flags |= REQ_RW;
 289                 rq->cmd[1] = 0x10;
 290                 rq->cmd[4] = len;
 291                 break;
 292         case MODE_SELECT_10:
 293                 len = sizeof(long_trespass);
 294                 rq->cmd_flags |= REQ_RW;
 295                 rq->cmd[1] = 0x10;
 296                 rq->cmd[8] = len;
 297                 break;
 298         case INQUIRY:
 299                 len = CLARIION_BUFFER_SIZE;
 300                 rq->cmd[4] = len;
 301                 memset(buffer, 0, len);
 302                 break;
 303         default:
 304                 BUG_ON(1);
 305                 break;
 306         }
 307
 308         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 309         rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
 310                          REQ_FAILFAST_DRIVER;
 311         rq->timeout = CLARIION_TIMEOUT;
 312         rq->retries = CLARIION_RETRIES;
 313
 314         if (blk_rq_map_kern(rq->q, rq, buffer, len, GFP_NOIO)) {
 315                 blk_put_request(rq);
 316                 return NULL;
 317         }
 318
 319         return rq;
 320 }
 321
 322 static int send_inquiry_cmd(struct scsi_device *sdev, int page,
 323                             struct clariion_dh_data *csdev)
 324 {
 325         struct request *rq = get_req(sdev, INQUIRY, csdev->buffer);
 326         int err;
 327
 328         if (!rq)
 329                 return SCSI_DH_RES_TEMP_UNAVAIL;
 330
 331         rq->sense = csdev->sense;
 332         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 333         rq->sense_len = csdev->senselen = 0;
 334
 335         rq->cmd[0] = INQUIRY;
 336         if (page != 0) {
 337                 rq->cmd[1] = 1;
 338                 rq->cmd[2] = page;
 339         }
 340         err = blk_execute_rq(sdev->request_queue, NULL, rq, 1);
 341         if (err == -EIO) {
 342                 sdev_printk(KERN_INFO, sdev,
 343                             "%s: failed to send %s INQUIRY: %x\n",
 344                             CLARIION_NAME, page?"EVPD":"standard",
 345                             rq->errors);
 346                 csdev->senselen = rq->sense_len;
 347                 err = SCSI_DH_IO;
 348         }
 349
 350         blk_put_request(rq);
 351
 352         return err;
 353 }
 354
 355 static int send_trespass_cmd(struct scsi_device *sdev,
 356                             struct clariion_dh_data *csdev)
 357 {
 358         struct request *rq;
 359         unsigned char *page22;
 360         int err, len, cmd;
 361
 362         if (csdev->flags & CLARIION_SHORT_TRESPASS) {
 363                 page22 = short_trespass;
 364                 if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
 365                         /* Set Honor Reservations bit */
 366                         page22[6] |= 0x80;
 367                 len = sizeof(short_trespass);
 368                 cmd = MODE_SELECT;
 369         } else {
 370                 page22 = long_trespass;
 371                 if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
 372                         /* Set Honor Reservations bit */
 373                         page22[10] |= 0x80;
 374                 len = sizeof(long_trespass);
 375                 cmd = MODE_SELECT_10;
 376         }
 377         BUG_ON((len > CLARIION_BUFFER_SIZE));
 378         memcpy(csdev->buffer, page22, len);
 379
 380         rq = get_req(sdev, cmd, csdev->buffer);
 381         if (!rq)
 382                 return SCSI_DH_RES_TEMP_UNAVAIL;
 383
 384         rq->sense = csdev->sense;
 385         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 386         rq->sense_len = csdev->senselen = 0;
 387
 388         err = blk_execute_rq(sdev->request_queue, NULL, rq, 1);
 389         if (err == -EIO) {
 390                 if (rq->sense_len) {
 391                         err = trespass_endio(sdev, csdev->sense);
 392                 } else {
 393                         sdev_printk(KERN_INFO, sdev,
 394                                     "%s: failed to send MODE SELECT: %x\n",
 395                                     CLARIION_NAME, rq->errors);
 396                 }
 397         }
 398
 399         blk_put_request(rq);
 400
 401         return err;
 402 }
 403
 404 static int clariion_check_sense(struct scsi_device *sdev,
 405                                 struct scsi_sense_hdr *sense_hdr)
 406 {
 407         switch (sense_hdr->sense_key) {
 408         case NOT_READY:
 409                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x03)
 410                         /*
 411                          * LUN Not Ready - Manual Intervention Required
 412                          * indicates this is a passive path.
 413                          *
 414                          * FIXME: However, if this is seen and EVPD C0
 415                          * indicates that this is due to a NDU in
 416                          * progress, we should set FAIL_PATH too.
 417                          * This indicates we might have to do a SCSI
 418                          * inquiry in the end_io path. Ugh.
 419                          *
 420                          * Can return FAILED only when we want the error
 421                          * recovery process to kick in.
 422                          */
 423                         return SUCCESS;
 424                 break;
 425         case ILLEGAL_REQUEST:
 426                 if (sense_hdr->asc == 0x25 && sense_hdr->ascq == 0x01)
 427                         /*
 428                          * An array based copy is in progress. Do not
 429                          * fail the path, do not bypass to another PG,
 430                          * do not retry. Fail the IO immediately.
 431                          * (Actually this is the same conclusion as in
 432                          * the default handler, but lets make sure.)
 433                          *
 434                          * Can return FAILED only when we want the error
 435                          * recovery process to kick in.
 436                          */
 437                         return SUCCESS;
 438                 break;
 439         case UNIT_ATTENTION:
 440                 if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
 441                         /*
 442                          * Unit Attention Code. This is the first IO
 443                          * to the new path, so just retry.
 444                          */
 445                         return ADD_TO_MLQUEUE;
 446                 break;
 447         }
 448
 449         return SCSI_RETURN_NOT_HANDLED;
 450 }
 451
 452 static int clariion_prep_fn(struct scsi_device *sdev, struct request *req)
 453 {
 454         struct clariion_dh_data *h = get_clariion_data(sdev);
 455         int ret = BLKPREP_OK;
 456
 457         if (h->lun_state != CLARIION_LUN_OWNED) {
 458                 ret = BLKPREP_KILL;
 459                 req->cmd_flags |= REQ_QUIET;
 460         }
 461         return ret;
 462
 463 }
 464
 465 static int clariion_std_inquiry(struct scsi_device *sdev,
 466                                 struct clariion_dh_data *csdev)
 467 {
 468         int err;
 469         char *sp_model;
 470
 471         err = send_inquiry_cmd(sdev, 0, csdev);
 472         if (err != SCSI_DH_OK && csdev->senselen) {
 473                 struct scsi_sense_hdr sshdr;
 474
 475                 if (scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
 476                                          &sshdr)) {
 477                         sdev_printk(KERN_ERR, sdev, "%s: INQUIRY sense code "
 478                                     "%02x/%02x/%02x\n", CLARIION_NAME,
 479                                     sshdr.sense_key, sshdr.asc, sshdr.ascq);
 480                 }
 481                 err = SCSI_DH_IO;
 482                 goto out;
 483         }
 484
 485         sp_model = parse_sp_model(sdev, csdev->buffer);
 486         if (!sp_model) {
 487                 err = SCSI_DH_DEV_UNSUPP;
 488                 goto out;
 489         }
 490
 491         /*
 492          * FC Series arrays do not support long trespass
 493          */
 494         if (!strlen(sp_model) || !strncmp(sp_model, "FC",2))
 495                 csdev->flags |= CLARIION_SHORT_TRESPASS;
 496
 497         sdev_printk(KERN_INFO, sdev,
 498                     "%s: detected Clariion %s, flags %x\n",
 499                     CLARIION_NAME, sp_model, csdev->flags);
 500 out:
 501         return err;
 502 }
 503
 504 static int clariion_send_inquiry(struct scsi_device *sdev,
 505                                  struct clariion_dh_data *csdev)
 506 {
 507         int err, retry = CLARIION_RETRIES;
 508
 509 retry:
 510         err = send_inquiry_cmd(sdev, 0xC0, csdev);
 511         if (err != SCSI_DH_OK && csdev->senselen) {
 512                 struct scsi_sense_hdr sshdr;
 513
 514                 err = scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
 515                                            &sshdr);
 516                 if (!err)
 517                         return SCSI_DH_IO;
 518
 519                 err = clariion_check_sense(sdev, &sshdr);
 520                 if (retry > 0 && err == ADD_TO_MLQUEUE) {
 521                         retry--;
 522                         goto retry;
 523                 }
 524                 sdev_printk(KERN_ERR, sdev, "%s: INQUIRY sense code "
 525                             "%02x/%02x/%02x\n", CLARIION_NAME,
 526                               sshdr.sense_key, sshdr.asc, sshdr.ascq);
 527                 err = SCSI_DH_IO;
 528         } else {
 529                 err = parse_sp_info_reply(sdev, csdev);
 530         }
 531         return err;
 532 }
 533
 534 static int clariion_activate(struct scsi_device *sdev,
 535                                 activate_complete fn, void *data)
 536 {
 537         struct clariion_dh_data *csdev = get_clariion_data(sdev);
 538         int result;
 539
 540         result = clariion_send_inquiry(sdev, csdev);
 541         if (result != SCSI_DH_OK)
 542                 goto done;
 543
 544         if (csdev->lun_state == CLARIION_LUN_OWNED)
 545                 goto done;
 546
 547         result = send_trespass_cmd(sdev, csdev);
 548         if (result != SCSI_DH_OK)
 549                 goto done;
 550         sdev_printk(KERN_INFO, sdev,"%s: %s trespass command sent\n",
 551                     CLARIION_NAME,
 552                     csdev->flags&CLARIION_SHORT_TRESPASS?"short":"long" );
 553
 554         /* Update status */
 555         result = clariion_send_inquiry(sdev, csdev);
 556         if (result != SCSI_DH_OK)
 557                 goto done;
 558
 559 done:
 560         sdev_printk(KERN_INFO, sdev,
 561                     "%s: at SP %c Port %d (%s, default SP %c)\n",
 562                     CLARIION_NAME, csdev->current_sp + 'A',
 563                     csdev->port, lun_state[csdev->lun_state],
 564                     csdev->default_sp + 'A');
 565
 566         if (fn)
 567                 fn(data, result);
 568         return 0;
 569 }
 570 /*
 571  * params - parameters in the following format
 572  *      "no_of_params\0param1\0param2\0param3\0...\0"
 573  *      for example, string for 2 parameters with value 10 and 21
 574  *      is specified as "2\010\021\0".
 575  */
 576 static int clariion_set_params(struct scsi_device *sdev, const char *params)
 577 {
 578         struct clariion_dh_data *csdev = get_clariion_data(sdev);
 579         unsigned int hr = 0, st = 0, argc;
 580         const char *p = params;
 581         int result = SCSI_DH_OK;
 582
 583         if ((sscanf(params, "%u", &argc) != 1) || (argc != 2))
 584                 return -EINVAL;
 585
 586         while (*p++)
 587                 ;
 588         if ((sscanf(p, "%u", &st) != 1) || (st > 1))
 589                 return -EINVAL;
 590
 591         while (*p++)
 592                 ;
 593         if ((sscanf(p, "%u", &hr) != 1) || (hr > 1))
 594                 return -EINVAL;
 595
 596         if (st)
 597                 csdev->flags |= CLARIION_SHORT_TRESPASS;
 598         else
 599                 csdev->flags &= ~CLARIION_SHORT_TRESPASS;
 600
 601         if (hr)
 602                 csdev->flags |= CLARIION_HONOR_RESERVATIONS;
 603         else
 604                 csdev->flags &= ~CLARIION_HONOR_RESERVATIONS;
 605
 606         /*
 607          * If this path is owned, we have to send a trespass command
 608          * with the new parameters. If not, simply return. Next trespass
 609          * command would use the parameters.
 610          */
 611         if (csdev->lun_state != CLARIION_LUN_OWNED)
 612                 goto done;
 613
 614         csdev->lun_state = CLARIION_LUN_UNINITIALIZED;
 615         result = send_trespass_cmd(sdev, csdev);
 616         if (result != SCSI_DH_OK)
 617                 goto done;
 618
 619         /* Update status */
 620         result = clariion_send_inquiry(sdev, csdev);
 621
 622 done:
 623         return result;
 624 }
 625
 626 static const struct scsi_dh_devlist clariion_dev_list[] = {
 627         {"DGC", "RAID"},
 628         {"DGC", "DISK"},
 629         {"DGC", "VRAID"},
 630         {NULL, NULL},
 631 };
 632
 633 static int clariion_bus_attach(struct scsi_device *sdev);
 634 static void clariion_bus_detach(struct scsi_device *sdev);
 635
 636 static struct scsi_device_handler clariion_dh = {
 637         .name           = CLARIION_NAME,
 638         .module         = THIS_MODULE,
 639         .devlist        = clariion_dev_list,
 640         .attach         = clariion_bus_attach,
 641         .detach         = clariion_bus_detach,
 642         .check_sense    = clariion_check_sense,
 643         .activate       = clariion_activate,
 644         .prep_fn        = clariion_prep_fn,
 645         .set_params     = clariion_set_params,
 646 };
 647
 648 static int clariion_bus_attach(struct scsi_device *sdev)
 649 {
 650         struct scsi_dh_data *scsi_dh_data;
 651         struct clariion_dh_data *h;
 652         unsigned long flags;
 653         int err;
 654
 655         scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
 656                                + sizeof(*h) , GFP_KERNEL);
 657         if (!scsi_dh_data) {
 658                 sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
 659                             CLARIION_NAME);
 660                 return -ENOMEM;
 661         }
 662
 663         scsi_dh_data->scsi_dh = &clariion_dh;
 664         h = (struct clariion_dh_data *) scsi_dh_data->buf;
 665         h->lun_state = CLARIION_LUN_UNINITIALIZED;
 666         h->default_sp = CLARIION_UNBOUND_LU;
 667         h->current_sp = CLARIION_UNBOUND_LU;
 668
 669         err = clariion_std_inquiry(sdev, h);
 670         if (err != SCSI_DH_OK)
 671                 goto failed;
 672
 673         err = clariion_send_inquiry(sdev, h);
 674         if (err != SCSI_DH_OK)
 675                 goto failed;
 676
 677         if (!try_module_get(THIS_MODULE))
 678                 goto failed;
 679
 680         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
 681         sdev->scsi_dh_data = scsi_dh_data;
 682         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
 683
 684         sdev_printk(KERN_INFO, sdev,
 685                     "%s: connected to SP %c Port %d (%s, default SP %c)\n",
 686                     CLARIION_NAME, h->current_sp + 'A',
 687                     h->port, lun_state[h->lun_state],
 688                     h->default_sp + 'A');
 689
 690         return 0;
 691
 692 failed:
 693         kfree(scsi_dh_data);
 694         sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
 695                     CLARIION_NAME);
 696         return -EINVAL;
 697 }
 698
 699 static void clariion_bus_detach(struct scsi_device *sdev)
 700 {
 701         struct scsi_dh_data *scsi_dh_data;
 702         unsigned long flags;
 703
 704         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
 705         scsi_dh_data = sdev->scsi_dh_data;
 706         sdev->scsi_dh_data = NULL;
 707         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
 708
 709         sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n",
 710                     CLARIION_NAME);
 711
 712         kfree(scsi_dh_data);
 713         module_put(THIS_MODULE);
 714 }
 715
 716 static int __init clariion_init(void)
 717 {
 718         int r;
 719
 720         r = scsi_register_device_handler(&clariion_dh);
 721         if (r != 0)
 722                 printk(KERN_ERR "%s: Failed to register scsi device handler.",
 723                         CLARIION_NAME);
 724         return r;
 725 }
 726
 727 static void __exit clariion_exit(void)
 728 {
 729         scsi_unregister_device_handler(&clariion_dh);
 730 }
 731
 732 module_init(clariion_init);
 733 module_exit(clariion_exit);
 734
 735 MODULE_DESCRIPTION("EMC CX/AX/FC-family driver");
 736 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, Chandra Seetharaman <sekharan@us.ibm.com>");
 737 MODULE_LICENSE("GPL");