drivers/scsi/device_handler/scsi_dh_rdac.c

   1 /*
   2  * LSI/Engenio/NetApp E-Series RDAC SCSI Device Handler
   3  *
   4  * Copyright (C) 2005 Mike Christie. All rights reserved.
   5  * Copyright (C) Chandra Seetharaman, IBM Corp. 2007
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  *
  21  */
  22 #include <scsi/scsi.h>
  23 #include <scsi/scsi_eh.h>
  24 #include <scsi/scsi_dh.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/slab.h>
  27 #include <linux/module.h>
  28
  29 #define RDAC_NAME "rdac"
  30 #define RDAC_RETRY_COUNT 5
  31
  32 /*
  33  * LSI mode page stuff
  34  *
  35  * These struct definitions and the forming of the
  36  * mode page were taken from the LSI RDAC 2.4 GPL'd
  37  * driver, and then converted to Linux conventions.
  38  */
  39 #define RDAC_QUIESCENCE_TIME 20
  40 /*
  41  * Page Codes
  42  */
  43 #define RDAC_PAGE_CODE_REDUNDANT_CONTROLLER 0x2c
  44
  45 /*
  46  * Controller modes definitions
  47  */
  48 #define RDAC_MODE_TRANSFER_SPECIFIED_LUNS       0x02
  49
  50 /*
  51  * RDAC Options field
  52  */
  53 #define RDAC_FORCED_QUIESENCE 0x02
  54
  55 #define RDAC_TIMEOUT    (60 * HZ)
  56 #define RDAC_RETRIES    3
  57
  58 struct rdac_mode_6_hdr {
  59         u8      data_len;
  60         u8      medium_type;
  61         u8      device_params;
  62         u8      block_desc_len;
  63 };
  64
  65 struct rdac_mode_10_hdr {
  66         u16     data_len;
  67         u8      medium_type;
  68         u8      device_params;
  69         u16     reserved;
  70         u16     block_desc_len;
  71 };
  72
  73 struct rdac_mode_common {
  74         u8      controller_serial[16];
  75         u8      alt_controller_serial[16];
  76         u8      rdac_mode[2];
  77         u8      alt_rdac_mode[2];
  78         u8      quiescence_timeout;
  79         u8      rdac_options;
  80 };
  81
  82 struct rdac_pg_legacy {
  83         struct rdac_mode_6_hdr hdr;
  84         u8      page_code;
  85         u8      page_len;
  86         struct rdac_mode_common common;
  87 #define MODE6_MAX_LUN   32
  88         u8      lun_table[MODE6_MAX_LUN];
  89         u8      reserved2[32];
  90         u8      reserved3;
  91         u8      reserved4;
  92 };
  93
  94 struct rdac_pg_expanded {
  95         struct rdac_mode_10_hdr hdr;
  96         u8      page_code;
  97         u8      subpage_code;
  98         u8      page_len[2];
  99         struct rdac_mode_common common;
 100         u8      lun_table[256];
 101         u8      reserved3;
 102         u8      reserved4;
 103 };
 104
 105 struct c9_inquiry {
 106         u8      peripheral_info;
 107         u8      page_code;      /* 0xC9 */
 108         u8      reserved1;
 109         u8      page_len;
 110         u8      page_id[4];     /* "vace" */
 111         u8      avte_cvp;
 112         u8      path_prio;
 113         u8      reserved2[38];
 114 };
 115
 116 #define SUBSYS_ID_LEN   16
 117 #define SLOT_ID_LEN     2
 118 #define ARRAY_LABEL_LEN 31
 119
 120 struct c4_inquiry {
 121         u8      peripheral_info;
 122         u8      page_code;      /* 0xC4 */
 123         u8      reserved1;
 124         u8      page_len;
 125         u8      page_id[4];     /* "subs" */
 126         u8      subsys_id[SUBSYS_ID_LEN];
 127         u8      revision[4];
 128         u8      slot_id[SLOT_ID_LEN];
 129         u8      reserved[2];
 130 };
 131
 132 #define UNIQUE_ID_LEN 16
 133 struct c8_inquiry {
 134         u8      peripheral_info;
 135         u8      page_code; /* 0xC8 */
 136         u8      reserved1;
 137         u8      page_len;
 138         u8      page_id[4]; /* "edid" */
 139         u8      reserved2[3];
 140         u8      vol_uniq_id_len;
 141         u8      vol_uniq_id[16];
 142         u8      vol_user_label_len;
 143         u8      vol_user_label[60];
 144         u8      array_uniq_id_len;
 145         u8      array_unique_id[UNIQUE_ID_LEN];
 146         u8      array_user_label_len;
 147         u8      array_user_label[60];
 148         u8      lun[8];
 149 };
 150
 151 struct rdac_controller {
 152         u8                      array_id[UNIQUE_ID_LEN];
 153         int                     use_ms10;
 154         struct kref             kref;
 155         struct list_head        node; /* list of all controllers */
 156         union                   {
 157                 struct rdac_pg_legacy legacy;
 158                 struct rdac_pg_expanded expanded;
 159         } mode_select;
 160         u8      index;
 161         u8      array_name[ARRAY_LABEL_LEN];
 162         struct Scsi_Host        *host;
 163         spinlock_t              ms_lock;
 164         int                     ms_queued;
 165         struct work_struct      ms_work;
 166         struct scsi_device      *ms_sdev;
 167         struct list_head        ms_head;
 168 };
 169
 170 struct c2_inquiry {
 171         u8      peripheral_info;
 172         u8      page_code;      /* 0xC2 */
 173         u8      reserved1;
 174         u8      page_len;
 175         u8      page_id[4];     /* "swr4" */
 176         u8      sw_version[3];
 177         u8      sw_date[3];
 178         u8      features_enabled;
 179         u8      max_lun_supported;
 180         u8      partitions[239]; /* Total allocation length should be 0xFF */
 181 };
 182
 183 struct rdac_dh_data {
 184         struct rdac_controller  *ctlr;
 185 #define UNINITIALIZED_LUN       (1 << 8)
 186         unsigned                lun;
 187
 188 #define RDAC_MODE               0
 189 #define RDAC_MODE_AVT           1
 190 #define RDAC_MODE_IOSHIP        2
 191         unsigned char           mode;
 192
 193 #define RDAC_STATE_ACTIVE       0
 194 #define RDAC_STATE_PASSIVE      1
 195         unsigned char           state;
 196
 197 #define RDAC_LUN_UNOWNED        0
 198 #define RDAC_LUN_OWNED          1
 199         char                    lun_state;
 200
 201 #define RDAC_PREFERRED          0
 202 #define RDAC_NON_PREFERRED      1
 203         char                    preferred;
 204
 205         unsigned char           sense[SCSI_SENSE_BUFFERSIZE];
 206         union                   {
 207                 struct c2_inquiry c2;
 208                 struct c4_inquiry c4;
 209                 struct c8_inquiry c8;
 210                 struct c9_inquiry c9;
 211         } inq;
 212 };
 213
 214 static const char *mode[] = {
 215         "RDAC",
 216         "AVT",
 217         "IOSHIP",
 218 };
 219 static const char *lun_state[] =
 220 {
 221         "unowned",
 222         "owned",
 223 };
 224
 225 struct rdac_queue_data {
 226         struct list_head        entry;
 227         struct rdac_dh_data     *h;
 228         activate_complete       callback_fn;
 229         void                    *callback_data;
 230 };
 231
 232 static LIST_HEAD(ctlr_list);
 233 static DEFINE_SPINLOCK(list_lock);
 234 static struct workqueue_struct *kmpath_rdacd;
 235 static void send_mode_select(struct work_struct *work);
 236
 237 /*
 238  * module parameter to enable rdac debug logging.
 239  * 2 bits for each type of logging, only two types defined for now
 240  * Can be enhanced if required at later point
 241  */
 242 static int rdac_logging = 1;
 243 module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
 244 MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, "
 245                 "Default is 1 - failover logging enabled, "
 246                 "set it to 0xF to enable all the logs");
 247
 248 #define RDAC_LOG_FAILOVER       0
 249 #define RDAC_LOG_SENSE          2
 250
 251 #define RDAC_LOG_BITS           2
 252
 253 #define RDAC_LOG_LEVEL(SHIFT)  \
 254         ((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1))
 255
 256 #define RDAC_LOG(SHIFT, sdev, f, arg...) \
 257 do { \
 258         if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
 259                 sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
 260 } while (0);
 261
 262 static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
 263 {
 264         struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
 265         BUG_ON(scsi_dh_data == NULL);
 266         return ((struct rdac_dh_data *) scsi_dh_data->buf);
 267 }
 268
 269 static struct request *get_rdac_req(struct scsi_device *sdev,
 270                         void *buffer, unsigned buflen, int rw)
 271 {
 272         struct request *rq;
 273         struct request_queue *q = sdev->request_queue;
 274
 275         rq = blk_get_request(q, rw, GFP_NOIO);
 276
 277         if (!rq) {
 278                 sdev_printk(KERN_INFO, sdev,
 279                                 "get_rdac_req: blk_get_request failed.\n");
 280                 return NULL;
 281         }
 282
 283         if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
 284                 blk_put_request(rq);
 285                 sdev_printk(KERN_INFO, sdev,
 286                                 "get_rdac_req: blk_rq_map_kern failed.\n");
 287                 return NULL;
 288         }
 289
 290         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 291         rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
 292                          REQ_FAILFAST_DRIVER;
 293         rq->retries = RDAC_RETRIES;
 294         rq->timeout = RDAC_TIMEOUT;
 295
 296         return rq;
 297 }
 298
 299 static struct request *rdac_failover_get(struct scsi_device *sdev,
 300                         struct rdac_dh_data *h, struct list_head *list)
 301 {
 302         struct request *rq;
 303         struct rdac_mode_common *common;
 304         unsigned data_size;
 305         struct rdac_queue_data *qdata;
 306         u8 *lun_table;
 307
 308         if (h->ctlr->use_ms10) {
 309                 struct rdac_pg_expanded *rdac_pg;
 310
 311                 data_size = sizeof(struct rdac_pg_expanded);
 312                 rdac_pg = &h->ctlr->mode_select.expanded;
 313                 memset(rdac_pg, 0, data_size);
 314                 common = &rdac_pg->common;
 315                 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40;
 316                 rdac_pg->subpage_code = 0x1;
 317                 rdac_pg->page_len[0] = 0x01;
 318                 rdac_pg->page_len[1] = 0x28;
 319                 lun_table = rdac_pg->lun_table;
 320         } else {
 321                 struct rdac_pg_legacy *rdac_pg;
 322
 323                 data_size = sizeof(struct rdac_pg_legacy);
 324                 rdac_pg = &h->ctlr->mode_select.legacy;
 325                 memset(rdac_pg, 0, data_size);
 326                 common = &rdac_pg->common;
 327                 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER;
 328                 rdac_pg->page_len = 0x68;
 329                 lun_table = rdac_pg->lun_table;
 330         }
 331         common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
 332         common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
 333         common->rdac_options = RDAC_FORCED_QUIESENCE;
 334
 335         list_for_each_entry(qdata, list, entry) {
 336                 lun_table[qdata->h->lun] = 0x81;
 337         }
 338
 339         /* get request for block layer packet command */
 340         rq = get_rdac_req(sdev, &h->ctlr->mode_select, data_size, WRITE);
 341         if (!rq)
 342                 return NULL;
 343
 344         /* Prepare the command. */
 345         if (h->ctlr->use_ms10) {
 346                 rq->cmd[0] = MODE_SELECT_10;
 347                 rq->cmd[7] = data_size >> 8;
 348                 rq->cmd[8] = data_size & 0xff;
 349         } else {
 350                 rq->cmd[0] = MODE_SELECT;
 351                 rq->cmd[4] = data_size;
 352         }
 353         rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
 354
 355         rq->sense = h->sense;
 356         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 357         rq->sense_len = 0;
 358
 359         return rq;
 360 }
 361
 362 static void release_controller(struct kref *kref)
 363 {
 364         struct rdac_controller *ctlr;
 365         ctlr = container_of(kref, struct rdac_controller, kref);
 366
 367         flush_workqueue(kmpath_rdacd);
 368         spin_lock(&list_lock);
 369         list_del(&ctlr->node);
 370         spin_unlock(&list_lock);
 371         kfree(ctlr);
 372 }
 373
 374 static struct rdac_controller *get_controller(int index, char *array_name,
 375                         u8 *array_id, struct scsi_device *sdev)
 376 {
 377         struct rdac_controller *ctlr, *tmp;
 378
 379         spin_lock(&list_lock);
 380
 381         list_for_each_entry(tmp, &ctlr_list, node) {
 382                 if ((memcmp(tmp->array_id, array_id, UNIQUE_ID_LEN) == 0) &&
 383                           (tmp->index == index) &&
 384                           (tmp->host == sdev->host)) {
 385                         kref_get(&tmp->kref);
 386                         spin_unlock(&list_lock);
 387                         return tmp;
 388                 }
 389         }
 390         ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
 391         if (!ctlr)
 392                 goto done;
 393
 394         /* initialize fields of controller */
 395         memcpy(ctlr->array_id, array_id, UNIQUE_ID_LEN);
 396         ctlr->index = index;
 397         ctlr->host = sdev->host;
 398         memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN);
 399
 400         kref_init(&ctlr->kref);
 401         ctlr->use_ms10 = -1;
 402         ctlr->ms_queued = 0;
 403         ctlr->ms_sdev = NULL;
 404         spin_lock_init(&ctlr->ms_lock);
 405         INIT_WORK(&ctlr->ms_work, send_mode_select);
 406         INIT_LIST_HEAD(&ctlr->ms_head);
 407         list_add(&ctlr->node, &ctlr_list);
 408 done:
 409         spin_unlock(&list_lock);
 410         return ctlr;
 411 }
 412
 413 static int submit_inquiry(struct scsi_device *sdev, int page_code,
 414                           unsigned int len, struct rdac_dh_data *h)
 415 {
 416         struct request *rq;
 417         struct request_queue *q = sdev->request_queue;
 418         int err = SCSI_DH_RES_TEMP_UNAVAIL;
 419
 420         rq = get_rdac_req(sdev, &h->inq, len, READ);
 421         if (!rq)
 422                 goto done;
 423
 424         /* Prepare the command. */
 425         rq->cmd[0] = INQUIRY;
 426         rq->cmd[1] = 1;
 427         rq->cmd[2] = page_code;
 428         rq->cmd[4] = len;
 429         rq->cmd_len = COMMAND_SIZE(INQUIRY);
 430
 431         rq->sense = h->sense;
 432         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 433         rq->sense_len = 0;
 434
 435         err = blk_execute_rq(q, NULL, rq, 1);
 436         if (err == -EIO)
 437                 err = SCSI_DH_IO;
 438
 439         blk_put_request(rq);
 440 done:
 441         return err;
 442 }
 443
 444 static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
 445                         char *array_name, u8 *array_id)
 446 {
 447         int err, i;
 448         struct c8_inquiry *inqp;
 449
 450         err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
 451         if (err == SCSI_DH_OK) {
 452                 inqp = &h->inq.c8;
 453                 if (inqp->page_code != 0xc8)
 454                         return SCSI_DH_NOSYS;
 455                 if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
 456                     inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
 457                         return SCSI_DH_NOSYS;
 458                 h->lun = inqp->lun[7]; /* Uses only the last byte */
 459
 460                 for(i=0; i<ARRAY_LABEL_LEN-1; ++i)
 461                         *(array_name+i) = inqp->array_user_label[(2*i)+1];
 462
 463                 *(array_name+ARRAY_LABEL_LEN-1) = '\0';
 464                 memset(array_id, 0, UNIQUE_ID_LEN);
 465                 memcpy(array_id, inqp->array_unique_id, inqp->array_uniq_id_len);
 466         }
 467         return err;
 468 }
 469
 470 static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
 471 {
 472         int err;
 473         struct c9_inquiry *inqp;
 474
 475         h->state = RDAC_STATE_ACTIVE;
 476         err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
 477         if (err == SCSI_DH_OK) {
 478                 inqp = &h->inq.c9;
 479                 /* detect the operating mode */
 480                 if ((inqp->avte_cvp >> 5) & 0x1)
 481                         h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */
 482                 else if (inqp->avte_cvp >> 7)
 483                         h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */
 484                 else
 485                         h->mode = RDAC_MODE; /* LUN in RDAC mode */
 486
 487                 /* Update ownership */
 488                 if (inqp->avte_cvp & 0x1)
 489                         h->lun_state = RDAC_LUN_OWNED;
 490                 else {
 491                         h->lun_state = RDAC_LUN_UNOWNED;
 492                         if (h->mode == RDAC_MODE)
 493                                 h->state = RDAC_STATE_PASSIVE;
 494                 }
 495
 496                 /* Update path prio*/
 497                 if (inqp->path_prio & 0x1)
 498                         h->preferred = RDAC_PREFERRED;
 499                 else
 500                         h->preferred = RDAC_NON_PREFERRED;
 501         }
 502
 503         return err;
 504 }
 505
 506 static int initialize_controller(struct scsi_device *sdev,
 507                 struct rdac_dh_data *h, char *array_name, u8 *array_id)
 508 {
 509         int err, index;
 510         struct c4_inquiry *inqp;
 511
 512         err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
 513         if (err == SCSI_DH_OK) {
 514                 inqp = &h->inq.c4;
 515                 /* get the controller index */
 516                 if (inqp->slot_id[1] == 0x31)
 517                         index = 0;
 518                 else
 519                         index = 1;
 520                 h->ctlr = get_controller(index, array_name, array_id, sdev);
 521                 if (!h->ctlr)
 522                         err = SCSI_DH_RES_TEMP_UNAVAIL;
 523         }
 524         return err;
 525 }
 526
 527 static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
 528 {
 529         int err;
 530         struct c2_inquiry *inqp;
 531
 532         err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
 533         if (err == SCSI_DH_OK) {
 534                 inqp = &h->inq.c2;
 535                 /*
 536                  * If more than MODE6_MAX_LUN luns are supported, use
 537                  * mode select 10
 538                  */
 539                 if (inqp->max_lun_supported >= MODE6_MAX_LUN)
 540                         h->ctlr->use_ms10 = 1;
 541                 else
 542                         h->ctlr->use_ms10 = 0;
 543         }
 544         return err;
 545 }
 546
 547 static int mode_select_handle_sense(struct scsi_device *sdev,
 548                                         unsigned char *sensebuf)
 549 {
 550         struct scsi_sense_hdr sense_hdr;
 551         int err = SCSI_DH_IO, ret;
 552         struct rdac_dh_data *h = get_rdac_data(sdev);
 553
 554         ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
 555         if (!ret)
 556                 goto done;
 557
 558         switch (sense_hdr.sense_key) {
 559         case NO_SENSE:
 560         case ABORTED_COMMAND:
 561         case UNIT_ATTENTION:
 562                 err = SCSI_DH_RETRY;
 563                 break;
 564         case NOT_READY:
 565                 if (sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x01)
 566                         /* LUN Not Ready and is in the Process of Becoming
 567                          * Ready
 568                          */
 569                         err = SCSI_DH_RETRY;
 570                 break;
 571         case ILLEGAL_REQUEST:
 572                 if (sense_hdr.asc == 0x91 && sense_hdr.ascq == 0x36)
 573                         /*
 574                          * Command Lock contention
 575                          */
 576                         err = SCSI_DH_RETRY;
 577                 break;
 578         default:
 579                 break;
 580         }
 581
 582         RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 583                 "MODE_SELECT returned with sense %02x/%02x/%02x",
 584                 (char *) h->ctlr->array_name, h->ctlr->index,
 585                 sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
 586
 587 done:
 588         return err;
 589 }
 590
 591 static void send_mode_select(struct work_struct *work)
 592 {
 593         struct rdac_controller *ctlr =
 594                 container_of(work, struct rdac_controller, ms_work);
 595         struct request *rq;
 596         struct scsi_device *sdev = ctlr->ms_sdev;
 597         struct rdac_dh_data *h = get_rdac_data(sdev);
 598         struct request_queue *q = sdev->request_queue;
 599         int err, retry_cnt = RDAC_RETRY_COUNT;
 600         struct rdac_queue_data *tmp, *qdata;
 601         LIST_HEAD(list);
 602
 603         spin_lock(&ctlr->ms_lock);
 604         list_splice_init(&ctlr->ms_head, &list);
 605         ctlr->ms_queued = 0;
 606         ctlr->ms_sdev = NULL;
 607         spin_unlock(&ctlr->ms_lock);
 608
 609 retry:
 610         err = SCSI_DH_RES_TEMP_UNAVAIL;
 611         rq = rdac_failover_get(sdev, h, &list);
 612         if (!rq)
 613                 goto done;
 614
 615         RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 616                 "%s MODE_SELECT command",
 617                 (char *) h->ctlr->array_name, h->ctlr->index,
 618                 (retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying");
 619
 620         err = blk_execute_rq(q, NULL, rq, 1);
 621         blk_put_request(rq);
 622         if (err != SCSI_DH_OK) {
 623                 err = mode_select_handle_sense(sdev, h->sense);
 624                 if (err == SCSI_DH_RETRY && retry_cnt--)
 625                         goto retry;
 626         }
 627         if (err == SCSI_DH_OK) {
 628                 h->state = RDAC_STATE_ACTIVE;
 629                 RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 630                                 "MODE_SELECT completed",
 631                                 (char *) h->ctlr->array_name, h->ctlr->index);
 632         }
 633
 634 done:
 635         list_for_each_entry_safe(qdata, tmp, &list, entry) {
 636                 list_del(&qdata->entry);
 637                 if (err == SCSI_DH_OK)
 638                         qdata->h->state = RDAC_STATE_ACTIVE;
 639                 if (qdata->callback_fn)
 640                         qdata->callback_fn(qdata->callback_data, err);
 641                 kfree(qdata);
 642         }
 643         return;
 644 }
 645
 646 static int queue_mode_select(struct scsi_device *sdev,
 647                                 activate_complete fn, void *data)
 648 {
 649         struct rdac_queue_data *qdata;
 650         struct rdac_controller *ctlr;
 651
 652         qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
 653         if (!qdata)
 654                 return SCSI_DH_RETRY;
 655
 656         qdata->h = get_rdac_data(sdev);
 657         qdata->callback_fn = fn;
 658         qdata->callback_data = data;
 659
 660         ctlr = qdata->h->ctlr;
 661         spin_lock(&ctlr->ms_lock);
 662         list_add_tail(&qdata->entry, &ctlr->ms_head);
 663         if (!ctlr->ms_queued) {
 664                 ctlr->ms_queued = 1;
 665                 ctlr->ms_sdev = sdev;
 666                 queue_work(kmpath_rdacd, &ctlr->ms_work);
 667         }
 668         spin_unlock(&ctlr->ms_lock);
 669         return SCSI_DH_OK;
 670 }
 671
 672 static int rdac_activate(struct scsi_device *sdev,
 673                         activate_complete fn, void *data)
 674 {
 675         struct rdac_dh_data *h = get_rdac_data(sdev);
 676         int err = SCSI_DH_OK;
 677         int act = 0;
 678
 679         err = check_ownership(sdev, h);
 680         if (err != SCSI_DH_OK)
 681                 goto done;
 682
 683         switch (h->mode) {
 684         case RDAC_MODE:
 685                 if (h->lun_state == RDAC_LUN_UNOWNED)
 686                         act = 1;
 687                 break;
 688         case RDAC_MODE_IOSHIP:
 689                 if ((h->lun_state == RDAC_LUN_UNOWNED) &&
 690                     (h->preferred == RDAC_PREFERRED))
 691                         act = 1;
 692                 break;
 693         default:
 694                 break;
 695         }
 696
 697         if (act) {
 698                 err = queue_mode_select(sdev, fn, data);
 699                 if (err == SCSI_DH_OK)
 700                         return 0;
 701         }
 702 done:
 703         if (fn)
 704                 fn(data, err);
 705         return 0;
 706 }
 707
 708 static int rdac_prep_fn(struct scsi_device *sdev, struct request *req)
 709 {
 710         struct rdac_dh_data *h = get_rdac_data(sdev);
 711         int ret = BLKPREP_OK;
 712
 713         if (h->state != RDAC_STATE_ACTIVE) {
 714                 ret = BLKPREP_KILL;
 715                 req->cmd_flags |= REQ_QUIET;
 716         }
 717         return ret;
 718
 719 }
 720
 721 static int rdac_check_sense(struct scsi_device *sdev,
 722                                 struct scsi_sense_hdr *sense_hdr)
 723 {
 724         struct rdac_dh_data *h = get_rdac_data(sdev);
 725
 726         RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, "
 727                         "I/O returned with sense %02x/%02x/%02x",
 728                         (char *) h->ctlr->array_name, h->ctlr->index,
 729                         sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq);
 730
 731         switch (sense_hdr->sense_key) {
 732         case NOT_READY:
 733                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01)
 734                         /* LUN Not Ready - Logical Unit Not Ready and is in
 735                         * the process of becoming ready
 736                         * Just retry.
 737                         */
 738                         return ADD_TO_MLQUEUE;
 739                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
 740                         /* LUN Not Ready - Storage firmware incompatible
 741                          * Manual code synchonisation required.
 742                          *
 743                          * Nothing we can do here. Try to bypass the path.
 744                          */
 745                         return SUCCESS;
 746                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1)
 747                         /* LUN Not Ready - Quiescense in progress
 748                          *
 749                          * Just retry and wait.
 750                          */
 751                         return ADD_TO_MLQUEUE;
 752                 if (sense_hdr->asc == 0xA1  && sense_hdr->ascq == 0x02)
 753                         /* LUN Not Ready - Quiescense in progress
 754                          * or has been achieved
 755                          * Just retry.
 756                          */
 757                         return ADD_TO_MLQUEUE;
 758                 break;
 759         case ILLEGAL_REQUEST:
 760                 if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) {
 761                         /* Invalid Request - Current Logical Unit Ownership.
 762                          * Controller is not the current owner of the LUN,
 763                          * Fail the path, so that the other path be used.
 764                          */
 765                         h->state = RDAC_STATE_PASSIVE;
 766                         return SUCCESS;
 767                 }
 768                 break;
 769         case UNIT_ATTENTION:
 770                 if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
 771                         /*
 772                          * Power On, Reset, or Bus Device Reset, just retry.
 773                          */
 774                         return ADD_TO_MLQUEUE;
 775                 if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02)
 776                         /*
 777                          * Quiescence in progress , just retry.
 778                          */
 779                         return ADD_TO_MLQUEUE;
 780                 break;
 781         }
 782         /* success just means we do not care what scsi-ml does */
 783         return SCSI_RETURN_NOT_HANDLED;
 784 }
 785
 786 static const struct scsi_dh_devlist rdac_dev_list[] = {
 787         {"IBM", "1722"},
 788         {"IBM", "1724"},
 789         {"IBM", "1726"},
 790         {"IBM", "1742"},
 791         {"IBM", "1745"},
 792         {"IBM", "1746"},
 793         {"IBM", "1814"},
 794         {"IBM", "1815"},
 795         {"IBM", "1818"},
 796         {"IBM", "3526"},
 797         {"SGI", "TP9400"},
 798         {"SGI", "TP9500"},
 799         {"SGI", "TP9700"},
 800         {"SGI", "IS"},
 801         {"STK", "OPENstorage D280"},
 802         {"SUN", "CSM200_R"},
 803         {"SUN", "LCSM100_I"},
 804         {"SUN", "LCSM100_S"},
 805         {"SUN", "LCSM100_E"},
 806         {"SUN", "LCSM100_F"},
 807         {"DELL", "MD3000"},
 808         {"DELL", "MD3000i"},
 809         {"DELL", "MD32xx"},
 810         {"DELL", "MD32xxi"},
 811         {"DELL", "MD36xxi"},
 812         {"DELL", "MD36xxf"},
 813         {"LSI", "INF-01-00"},
 814         {"ENGENIO", "INF-01-00"},
 815         {"STK", "FLEXLINE 380"},
 816         {"SUN", "CSM100_R_FC"},
 817         {"SUN", "STK6580_6780"},
 818         {"SUN", "SUN_6180"},
 819         {"SUN", "ArrayStorage"},
 820         {NULL, NULL},
 821 };
 822
 823 static int rdac_bus_attach(struct scsi_device *sdev);
 824 static void rdac_bus_detach(struct scsi_device *sdev);
 825
 826 static struct scsi_device_handler rdac_dh = {
 827         .name = RDAC_NAME,
 828         .module = THIS_MODULE,
 829         .devlist = rdac_dev_list,
 830         .prep_fn = rdac_prep_fn,
 831         .check_sense = rdac_check_sense,
 832         .attach = rdac_bus_attach,
 833         .detach = rdac_bus_detach,
 834         .activate = rdac_activate,
 835 };
 836
 837 static int rdac_bus_attach(struct scsi_device *sdev)
 838 {
 839         struct scsi_dh_data *scsi_dh_data;
 840         struct rdac_dh_data *h;
 841         unsigned long flags;
 842         int err;
 843         char array_name[ARRAY_LABEL_LEN];
 844         char array_id[UNIQUE_ID_LEN];
 845
 846         scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
 847                                + sizeof(*h) , GFP_KERNEL);
 848         if (!scsi_dh_data) {
 849                 sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
 850                             RDAC_NAME);
 851                 return 0;
 852         }
 853
 854         scsi_dh_data->scsi_dh = &rdac_dh;
 855         h = (struct rdac_dh_data *) scsi_dh_data->buf;
 856         h->lun = UNINITIALIZED_LUN;
 857         h->state = RDAC_STATE_ACTIVE;
 858
 859         err = get_lun_info(sdev, h, array_name, array_id);
 860         if (err != SCSI_DH_OK)
 861                 goto failed;
 862
 863         err = initialize_controller(sdev, h, array_name, array_id);
 864         if (err != SCSI_DH_OK)
 865                 goto failed;
 866
 867         err = check_ownership(sdev, h);
 868         if (err != SCSI_DH_OK)
 869                 goto clean_ctlr;
 870
 871         err = set_mode_select(sdev, h);
 872         if (err != SCSI_DH_OK)
 873                 goto clean_ctlr;
 874
 875         if (!try_module_get(THIS_MODULE))
 876                 goto clean_ctlr;
 877
 878         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
 879         sdev->scsi_dh_data = scsi_dh_data;
 880         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
 881
 882         sdev_printk(KERN_NOTICE, sdev,
 883                     "%s: LUN %d (%s) (%s)\n",
 884                     RDAC_NAME, h->lun, mode[(int)h->mode],
 885                     lun_state[(int)h->lun_state]);
 886
 887         return 0;
 888
 889 clean_ctlr:
 890         kref_put(&h->ctlr->kref, release_controller);
 891
 892 failed:
 893         kfree(scsi_dh_data);
 894         sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
 895                     RDAC_NAME);
 896         return -EINVAL;
 897 }
 898
 899 static void rdac_bus_detach( struct scsi_device *sdev )
 900 {
 901         struct scsi_dh_data *scsi_dh_data;
 902         struct rdac_dh_data *h;
 903         unsigned long flags;
 904
 905         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
 906         scsi_dh_data = sdev->scsi_dh_data;
 907         sdev->scsi_dh_data = NULL;
 908         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
 909
 910         h = (struct rdac_dh_data *) scsi_dh_data->buf;
 911         if (h->ctlr)
 912                 kref_put(&h->ctlr->kref, release_controller);
 913         kfree(scsi_dh_data);
 914         module_put(THIS_MODULE);
 915         sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", RDAC_NAME);
 916 }
 917
 918
 919
 920 static int __init rdac_init(void)
 921 {
 922         int r;
 923
 924         r = scsi_register_device_handler(&rdac_dh);
 925         if (r != 0) {
 926                 printk(KERN_ERR "Failed to register scsi device handler.");
 927                 goto done;
 928         }
 929
 930         /*
 931          * Create workqueue to handle mode selects for rdac
 932          */
 933         kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd");
 934         if (!kmpath_rdacd) {
 935                 scsi_unregister_device_handler(&rdac_dh);
 936                 printk(KERN_ERR "kmpath_rdacd creation failed.\n");
 937         }
 938 done:
 939         return r;
 940 }
 941
 942 static void __exit rdac_exit(void)
 943 {
 944         destroy_workqueue(kmpath_rdacd);
 945         scsi_unregister_device_handler(&rdac_dh);
 946 }
 947
 948 module_init(rdac_init);
 949 module_exit(rdac_exit);
 950
 951 MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver");
 952 MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
 953 MODULE_VERSION("01.00.0000.0000");
 954 MODULE_LICENSE("GPL");