kernel/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 scsi_dh_data     dh_data;
 185         struct rdac_controller  *ctlr;
 186 #define UNINITIALIZED_LUN       (1 << 8)
 187         unsigned                lun;
 188
 189 #define RDAC_MODE               0
 190 #define RDAC_MODE_AVT           1
 191 #define RDAC_MODE_IOSHIP        2
 192         unsigned char           mode;
 193
 194 #define RDAC_STATE_ACTIVE       0
 195 #define RDAC_STATE_PASSIVE      1
 196         unsigned char           state;
 197
 198 #define RDAC_LUN_UNOWNED        0
 199 #define RDAC_LUN_OWNED          1
 200         char                    lun_state;
 201
 202 #define RDAC_PREFERRED          0
 203 #define RDAC_NON_PREFERRED      1
 204         char                    preferred;
 205
 206         unsigned char           sense[SCSI_SENSE_BUFFERSIZE];
 207         union                   {
 208                 struct c2_inquiry c2;
 209                 struct c4_inquiry c4;
 210                 struct c8_inquiry c8;
 211                 struct c9_inquiry c9;
 212         } inq;
 213 };
 214
 215 static const char *mode[] = {
 216         "RDAC",
 217         "AVT",
 218         "IOSHIP",
 219 };
 220 static const char *lun_state[] =
 221 {
 222         "unowned",
 223         "owned",
 224 };
 225
 226 struct rdac_queue_data {
 227         struct list_head        entry;
 228         struct rdac_dh_data     *h;
 229         activate_complete       callback_fn;
 230         void                    *callback_data;
 231 };
 232
 233 static LIST_HEAD(ctlr_list);
 234 static DEFINE_SPINLOCK(list_lock);
 235 static struct workqueue_struct *kmpath_rdacd;
 236 static void send_mode_select(struct work_struct *work);
 237
 238 /*
 239  * module parameter to enable rdac debug logging.
 240  * 2 bits for each type of logging, only two types defined for now
 241  * Can be enhanced if required at later point
 242  */
 243 static int rdac_logging = 1;
 244 module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
 245 MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, "
 246                 "Default is 1 - failover logging enabled, "
 247                 "set it to 0xF to enable all the logs");
 248
 249 #define RDAC_LOG_FAILOVER       0
 250 #define RDAC_LOG_SENSE          2
 251
 252 #define RDAC_LOG_BITS           2
 253
 254 #define RDAC_LOG_LEVEL(SHIFT)  \
 255         ((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1))
 256
 257 #define RDAC_LOG(SHIFT, sdev, f, arg...) \
 258 do { \
 259         if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
 260                 sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
 261 } while (0);
 262
 263 static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
 264 {
 265         return container_of(sdev->scsi_dh_data, struct rdac_dh_data, dh_data);
 266 }
 267
 268 static struct request *get_rdac_req(struct scsi_device *sdev,
 269                         void *buffer, unsigned buflen, int rw)
 270 {
 271         struct request *rq;
 272         struct request_queue *q = sdev->request_queue;
 273
 274         rq = blk_get_request(q, rw, GFP_NOIO);
 275
 276         if (IS_ERR(rq)) {
 277                 sdev_printk(KERN_INFO, sdev,
 278                                 "get_rdac_req: blk_get_request failed.\n");
 279                 return NULL;
 280         }
 281         blk_rq_set_block_pc(rq);
 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_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
 291                          REQ_FAILFAST_DRIVER;
 292         rq->retries = RDAC_RETRIES;
 293         rq->timeout = RDAC_TIMEOUT;
 294
 295         return rq;
 296 }
 297
 298 static struct request *rdac_failover_get(struct scsi_device *sdev,
 299                         struct rdac_dh_data *h, struct list_head *list)
 300 {
 301         struct request *rq;
 302         struct rdac_mode_common *common;
 303         unsigned data_size;
 304         struct rdac_queue_data *qdata;
 305         u8 *lun_table;
 306
 307         if (h->ctlr->use_ms10) {
 308                 struct rdac_pg_expanded *rdac_pg;
 309
 310                 data_size = sizeof(struct rdac_pg_expanded);
 311                 rdac_pg = &h->ctlr->mode_select.expanded;
 312                 memset(rdac_pg, 0, data_size);
 313                 common = &rdac_pg->common;
 314                 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40;
 315                 rdac_pg->subpage_code = 0x1;
 316                 rdac_pg->page_len[0] = 0x01;
 317                 rdac_pg->page_len[1] = 0x28;
 318                 lun_table = rdac_pg->lun_table;
 319         } else {
 320                 struct rdac_pg_legacy *rdac_pg;
 321
 322                 data_size = sizeof(struct rdac_pg_legacy);
 323                 rdac_pg = &h->ctlr->mode_select.legacy;
 324                 memset(rdac_pg, 0, data_size);
 325                 common = &rdac_pg->common;
 326                 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER;
 327                 rdac_pg->page_len = 0x68;
 328                 lun_table = rdac_pg->lun_table;
 329         }
 330         common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
 331         common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
 332         common->rdac_options = RDAC_FORCED_QUIESENCE;
 333
 334         list_for_each_entry(qdata, list, entry) {
 335                 lun_table[qdata->h->lun] = 0x81;
 336         }
 337
 338         /* get request for block layer packet command */
 339         rq = get_rdac_req(sdev, &h->ctlr->mode_select, data_size, WRITE);
 340         if (!rq)
 341                 return NULL;
 342
 343         /* Prepare the command. */
 344         if (h->ctlr->use_ms10) {
 345                 rq->cmd[0] = MODE_SELECT_10;
 346                 rq->cmd[7] = data_size >> 8;
 347                 rq->cmd[8] = data_size & 0xff;
 348         } else {
 349                 rq->cmd[0] = MODE_SELECT;
 350                 rq->cmd[4] = data_size;
 351         }
 352         rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
 353
 354         rq->sense = h->sense;
 355         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 356         rq->sense_len = 0;
 357
 358         return rq;
 359 }
 360
 361 static void release_controller(struct kref *kref)
 362 {
 363         struct rdac_controller *ctlr;
 364         ctlr = container_of(kref, struct rdac_controller, kref);
 365
 366         list_del(&ctlr->node);
 367         kfree(ctlr);
 368 }
 369
 370 static struct rdac_controller *get_controller(int index, char *array_name,
 371                         u8 *array_id, struct scsi_device *sdev)
 372 {
 373         struct rdac_controller *ctlr, *tmp;
 374
 375         list_for_each_entry(tmp, &ctlr_list, node) {
 376                 if ((memcmp(tmp->array_id, array_id, UNIQUE_ID_LEN) == 0) &&
 377                           (tmp->index == index) &&
 378                           (tmp->host == sdev->host)) {
 379                         kref_get(&tmp->kref);
 380                         return tmp;
 381                 }
 382         }
 383         ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
 384         if (!ctlr)
 385                 return NULL;
 386
 387         /* initialize fields of controller */
 388         memcpy(ctlr->array_id, array_id, UNIQUE_ID_LEN);
 389         ctlr->index = index;
 390         ctlr->host = sdev->host;
 391         memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN);
 392
 393         kref_init(&ctlr->kref);
 394         ctlr->use_ms10 = -1;
 395         ctlr->ms_queued = 0;
 396         ctlr->ms_sdev = NULL;
 397         spin_lock_init(&ctlr->ms_lock);
 398         INIT_WORK(&ctlr->ms_work, send_mode_select);
 399         INIT_LIST_HEAD(&ctlr->ms_head);
 400         list_add(&ctlr->node, &ctlr_list);
 401
 402         return ctlr;
 403 }
 404
 405 static int submit_inquiry(struct scsi_device *sdev, int page_code,
 406                           unsigned int len, struct rdac_dh_data *h)
 407 {
 408         struct request *rq;
 409         struct request_queue *q = sdev->request_queue;
 410         int err = SCSI_DH_RES_TEMP_UNAVAIL;
 411
 412         rq = get_rdac_req(sdev, &h->inq, len, READ);
 413         if (!rq)
 414                 goto done;
 415
 416         /* Prepare the command. */
 417         rq->cmd[0] = INQUIRY;
 418         rq->cmd[1] = 1;
 419         rq->cmd[2] = page_code;
 420         rq->cmd[4] = len;
 421         rq->cmd_len = COMMAND_SIZE(INQUIRY);
 422
 423         rq->sense = h->sense;
 424         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 425         rq->sense_len = 0;
 426
 427         err = blk_execute_rq(q, NULL, rq, 1);
 428         if (err == -EIO)
 429                 err = SCSI_DH_IO;
 430
 431         blk_put_request(rq);
 432 done:
 433         return err;
 434 }
 435
 436 static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
 437                         char *array_name, u8 *array_id)
 438 {
 439         int err, i;
 440         struct c8_inquiry *inqp;
 441
 442         err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
 443         if (err == SCSI_DH_OK) {
 444                 inqp = &h->inq.c8;
 445                 if (inqp->page_code != 0xc8)
 446                         return SCSI_DH_NOSYS;
 447                 if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
 448                     inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
 449                         return SCSI_DH_NOSYS;
 450                 h->lun = inqp->lun[7]; /* Uses only the last byte */
 451
 452                 for(i=0; i<ARRAY_LABEL_LEN-1; ++i)
 453                         *(array_name+i) = inqp->array_user_label[(2*i)+1];
 454
 455                 *(array_name+ARRAY_LABEL_LEN-1) = '\0';
 456                 memset(array_id, 0, UNIQUE_ID_LEN);
 457                 memcpy(array_id, inqp->array_unique_id, inqp->array_uniq_id_len);
 458         }
 459         return err;
 460 }
 461
 462 static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
 463 {
 464         int err;
 465         struct c9_inquiry *inqp;
 466
 467         h->state = RDAC_STATE_ACTIVE;
 468         err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
 469         if (err == SCSI_DH_OK) {
 470                 inqp = &h->inq.c9;
 471                 /* detect the operating mode */
 472                 if ((inqp->avte_cvp >> 5) & 0x1)
 473                         h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */
 474                 else if (inqp->avte_cvp >> 7)
 475                         h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */
 476                 else
 477                         h->mode = RDAC_MODE; /* LUN in RDAC mode */
 478
 479                 /* Update ownership */
 480                 if (inqp->avte_cvp & 0x1)
 481                         h->lun_state = RDAC_LUN_OWNED;
 482                 else {
 483                         h->lun_state = RDAC_LUN_UNOWNED;
 484                         if (h->mode == RDAC_MODE)
 485                                 h->state = RDAC_STATE_PASSIVE;
 486                 }
 487
 488                 /* Update path prio*/
 489                 if (inqp->path_prio & 0x1)
 490                         h->preferred = RDAC_PREFERRED;
 491                 else
 492                         h->preferred = RDAC_NON_PREFERRED;
 493         }
 494
 495         return err;
 496 }
 497
 498 static int initialize_controller(struct scsi_device *sdev,
 499                 struct rdac_dh_data *h, char *array_name, u8 *array_id)
 500 {
 501         int err, index;
 502         struct c4_inquiry *inqp;
 503
 504         err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
 505         if (err == SCSI_DH_OK) {
 506                 inqp = &h->inq.c4;
 507                 /* get the controller index */
 508                 if (inqp->slot_id[1] == 0x31)
 509                         index = 0;
 510                 else
 511                         index = 1;
 512
 513                 spin_lock(&list_lock);
 514                 h->ctlr = get_controller(index, array_name, array_id, sdev);
 515                 if (!h->ctlr)
 516                         err = SCSI_DH_RES_TEMP_UNAVAIL;
 517                 spin_unlock(&list_lock);
 518         }
 519         return err;
 520 }
 521
 522 static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
 523 {
 524         int err;
 525         struct c2_inquiry *inqp;
 526
 527         err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
 528         if (err == SCSI_DH_OK) {
 529                 inqp = &h->inq.c2;
 530                 /*
 531                  * If more than MODE6_MAX_LUN luns are supported, use
 532                  * mode select 10
 533                  */
 534                 if (inqp->max_lun_supported >= MODE6_MAX_LUN)
 535                         h->ctlr->use_ms10 = 1;
 536                 else
 537                         h->ctlr->use_ms10 = 0;
 538         }
 539         return err;
 540 }
 541
 542 static int mode_select_handle_sense(struct scsi_device *sdev,
 543                                         unsigned char *sensebuf)
 544 {
 545         struct scsi_sense_hdr sense_hdr;
 546         int err = SCSI_DH_IO, ret;
 547         struct rdac_dh_data *h = get_rdac_data(sdev);
 548
 549         ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
 550         if (!ret)
 551                 goto done;
 552
 553         switch (sense_hdr.sense_key) {
 554         case NO_SENSE:
 555         case ABORTED_COMMAND:
 556         case UNIT_ATTENTION:
 557                 err = SCSI_DH_RETRY;
 558                 break;
 559         case NOT_READY:
 560                 if (sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x01)
 561                         /* LUN Not Ready and is in the Process of Becoming
 562                          * Ready
 563                          */
 564                         err = SCSI_DH_RETRY;
 565                 break;
 566         case ILLEGAL_REQUEST:
 567                 if (sense_hdr.asc == 0x91 && sense_hdr.ascq == 0x36)
 568                         /*
 569                          * Command Lock contention
 570                          */
 571                         err = SCSI_DH_RETRY;
 572                 break;
 573         default:
 574                 break;
 575         }
 576
 577         RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 578                 "MODE_SELECT returned with sense %02x/%02x/%02x",
 579                 (char *) h->ctlr->array_name, h->ctlr->index,
 580                 sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
 581
 582 done:
 583         return err;
 584 }
 585
 586 static void send_mode_select(struct work_struct *work)
 587 {
 588         struct rdac_controller *ctlr =
 589                 container_of(work, struct rdac_controller, ms_work);
 590         struct request *rq;
 591         struct scsi_device *sdev = ctlr->ms_sdev;
 592         struct rdac_dh_data *h = get_rdac_data(sdev);
 593         struct request_queue *q = sdev->request_queue;
 594         int err, retry_cnt = RDAC_RETRY_COUNT;
 595         struct rdac_queue_data *tmp, *qdata;
 596         LIST_HEAD(list);
 597
 598         spin_lock(&ctlr->ms_lock);
 599         list_splice_init(&ctlr->ms_head, &list);
 600         ctlr->ms_queued = 0;
 601         ctlr->ms_sdev = NULL;
 602         spin_unlock(&ctlr->ms_lock);
 603
 604 retry:
 605         err = SCSI_DH_RES_TEMP_UNAVAIL;
 606         rq = rdac_failover_get(sdev, h, &list);
 607         if (!rq)
 608                 goto done;
 609
 610         RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 611                 "%s MODE_SELECT command",
 612                 (char *) h->ctlr->array_name, h->ctlr->index,
 613                 (retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying");
 614
 615         err = blk_execute_rq(q, NULL, rq, 1);
 616         blk_put_request(rq);
 617         if (err != SCSI_DH_OK) {
 618                 err = mode_select_handle_sense(sdev, h->sense);
 619                 if (err == SCSI_DH_RETRY && retry_cnt--)
 620                         goto retry;
 621         }
 622         if (err == SCSI_DH_OK) {
 623                 h->state = RDAC_STATE_ACTIVE;
 624                 RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 625                                 "MODE_SELECT completed",
 626                                 (char *) h->ctlr->array_name, h->ctlr->index);
 627         }
 628
 629 done:
 630         list_for_each_entry_safe(qdata, tmp, &list, entry) {
 631                 list_del(&qdata->entry);
 632                 if (err == SCSI_DH_OK)
 633                         qdata->h->state = RDAC_STATE_ACTIVE;
 634                 if (qdata->callback_fn)
 635                         qdata->callback_fn(qdata->callback_data, err);
 636                 kfree(qdata);
 637         }
 638         return;
 639 }
 640
 641 static int queue_mode_select(struct scsi_device *sdev,
 642                                 activate_complete fn, void *data)
 643 {
 644         struct rdac_queue_data *qdata;
 645         struct rdac_controller *ctlr;
 646
 647         qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
 648         if (!qdata)
 649                 return SCSI_DH_RETRY;
 650
 651         qdata->h = get_rdac_data(sdev);
 652         qdata->callback_fn = fn;
 653         qdata->callback_data = data;
 654
 655         ctlr = qdata->h->ctlr;
 656         spin_lock(&ctlr->ms_lock);
 657         list_add_tail(&qdata->entry, &ctlr->ms_head);
 658         if (!ctlr->ms_queued) {
 659                 ctlr->ms_queued = 1;
 660                 ctlr->ms_sdev = sdev;
 661                 queue_work(kmpath_rdacd, &ctlr->ms_work);
 662         }
 663         spin_unlock(&ctlr->ms_lock);
 664         return SCSI_DH_OK;
 665 }
 666
 667 static int rdac_activate(struct scsi_device *sdev,
 668                         activate_complete fn, void *data)
 669 {
 670         struct rdac_dh_data *h = get_rdac_data(sdev);
 671         int err = SCSI_DH_OK;
 672         int act = 0;
 673
 674         err = check_ownership(sdev, h);
 675         if (err != SCSI_DH_OK)
 676                 goto done;
 677
 678         switch (h->mode) {
 679         case RDAC_MODE:
 680                 if (h->lun_state == RDAC_LUN_UNOWNED)
 681                         act = 1;
 682                 break;
 683         case RDAC_MODE_IOSHIP:
 684                 if ((h->lun_state == RDAC_LUN_UNOWNED) &&
 685                     (h->preferred == RDAC_PREFERRED))
 686                         act = 1;
 687                 break;
 688         default:
 689                 break;
 690         }
 691
 692         if (act) {
 693                 err = queue_mode_select(sdev, fn, data);
 694                 if (err == SCSI_DH_OK)
 695                         return 0;
 696         }
 697 done:
 698         if (fn)
 699                 fn(data, err);
 700         return 0;
 701 }
 702
 703 static int rdac_prep_fn(struct scsi_device *sdev, struct request *req)
 704 {
 705         struct rdac_dh_data *h = get_rdac_data(sdev);
 706         int ret = BLKPREP_OK;
 707
 708         if (h->state != RDAC_STATE_ACTIVE) {
 709                 ret = BLKPREP_KILL;
 710                 req->cmd_flags |= REQ_QUIET;
 711         }
 712         return ret;
 713
 714 }
 715
 716 static int rdac_check_sense(struct scsi_device *sdev,
 717                                 struct scsi_sense_hdr *sense_hdr)
 718 {
 719         struct rdac_dh_data *h = get_rdac_data(sdev);
 720
 721         RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, "
 722                         "I/O returned with sense %02x/%02x/%02x",
 723                         (char *) h->ctlr->array_name, h->ctlr->index,
 724                         sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq);
 725
 726         switch (sense_hdr->sense_key) {
 727         case NOT_READY:
 728                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01)
 729                         /* LUN Not Ready - Logical Unit Not Ready and is in
 730                         * the process of becoming ready
 731                         * Just retry.
 732                         */
 733                         return ADD_TO_MLQUEUE;
 734                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
 735                         /* LUN Not Ready - Storage firmware incompatible
 736                          * Manual code synchonisation required.
 737                          *
 738                          * Nothing we can do here. Try to bypass the path.
 739                          */
 740                         return SUCCESS;
 741                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1)
 742                         /* LUN Not Ready - Quiescense in progress
 743                          *
 744                          * Just retry and wait.
 745                          */
 746                         return ADD_TO_MLQUEUE;
 747                 if (sense_hdr->asc == 0xA1  && sense_hdr->ascq == 0x02)
 748                         /* LUN Not Ready - Quiescense in progress
 749                          * or has been achieved
 750                          * Just retry.
 751                          */
 752                         return ADD_TO_MLQUEUE;
 753                 break;
 754         case ILLEGAL_REQUEST:
 755                 if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) {
 756                         /* Invalid Request - Current Logical Unit Ownership.
 757                          * Controller is not the current owner of the LUN,
 758                          * Fail the path, so that the other path be used.
 759                          */
 760                         h->state = RDAC_STATE_PASSIVE;
 761                         return SUCCESS;
 762                 }
 763                 break;
 764         case UNIT_ATTENTION:
 765                 if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
 766                         /*
 767                          * Power On, Reset, or Bus Device Reset, just retry.
 768                          */
 769                         return ADD_TO_MLQUEUE;
 770                 if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02)
 771                         /*
 772                          * Quiescence in progress , just retry.
 773                          */
 774                         return ADD_TO_MLQUEUE;
 775                 break;
 776         }
 777         /* success just means we do not care what scsi-ml does */
 778         return SCSI_RETURN_NOT_HANDLED;
 779 }
 780
 781 static const struct {
 782         char *vendor;
 783         char *model;
 784 } rdac_dev_list[] = {
 785         {"IBM", "1722"},
 786         {"IBM", "1724"},
 787         {"IBM", "1726"},
 788         {"IBM", "1742"},
 789         {"IBM", "1745"},
 790         {"IBM", "1746"},
 791         {"IBM", "1813"},
 792         {"IBM", "1814"},
 793         {"IBM", "1815"},
 794         {"IBM", "1818"},
 795         {"IBM", "3526"},
 796         {"SGI", "TP9"},
 797         {"SGI", "IS"},
 798         {"STK", "OPENstorage D280"},
 799         {"STK", "FLEXLINE 380"},
 800         {"SUN", "CSM"},
 801         {"SUN", "LCSM100"},
 802         {"SUN", "STK6580_6780"},
 803         {"SUN", "SUN_6180"},
 804         {"SUN", "ArrayStorage"},
 805         {"DELL", "MD3"},
 806         {"NETAPP", "INF-01-00"},
 807         {"LSI", "INF-01-00"},
 808         {"ENGENIO", "INF-01-00"},
 809         {NULL, NULL},
 810 };
 811
 812 static bool rdac_match(struct scsi_device *sdev)
 813 {
 814         int i;
 815
 816         if (scsi_device_tpgs(sdev))
 817                 return false;
 818
 819         for (i = 0; rdac_dev_list[i].vendor; i++) {
 820                 if (!strncmp(sdev->vendor, rdac_dev_list[i].vendor,
 821                         strlen(rdac_dev_list[i].vendor)) &&
 822                     !strncmp(sdev->model, rdac_dev_list[i].model,
 823                         strlen(rdac_dev_list[i].model))) {
 824                         return true;
 825                 }
 826         }
 827         return false;
 828 }
 829
 830 static struct scsi_dh_data *rdac_bus_attach(struct scsi_device *sdev)
 831 {
 832         struct rdac_dh_data *h;
 833         int err;
 834         char array_name[ARRAY_LABEL_LEN];
 835         char array_id[UNIQUE_ID_LEN];
 836
 837         h = kzalloc(sizeof(*h) , GFP_KERNEL);
 838         if (!h)
 839                 return ERR_PTR(-ENOMEM);
 840         h->lun = UNINITIALIZED_LUN;
 841         h->state = RDAC_STATE_ACTIVE;
 842
 843         err = get_lun_info(sdev, h, array_name, array_id);
 844         if (err != SCSI_DH_OK)
 845                 goto failed;
 846
 847         err = initialize_controller(sdev, h, array_name, array_id);
 848         if (err != SCSI_DH_OK)
 849                 goto failed;
 850
 851         err = check_ownership(sdev, h);
 852         if (err != SCSI_DH_OK)
 853                 goto clean_ctlr;
 854
 855         err = set_mode_select(sdev, h);
 856         if (err != SCSI_DH_OK)
 857                 goto clean_ctlr;
 858
 859         sdev_printk(KERN_NOTICE, sdev,
 860                     "%s: LUN %d (%s) (%s)\n",
 861                     RDAC_NAME, h->lun, mode[(int)h->mode],
 862                     lun_state[(int)h->lun_state]);
 863
 864         return &h->dh_data;
 865
 866 clean_ctlr:
 867         spin_lock(&list_lock);
 868         kref_put(&h->ctlr->kref, release_controller);
 869         spin_unlock(&list_lock);
 870
 871 failed:
 872         kfree(h);
 873         return ERR_PTR(-EINVAL);
 874 }
 875
 876 static void rdac_bus_detach( struct scsi_device *sdev )
 877 {
 878         struct rdac_dh_data *h = get_rdac_data(sdev);
 879
 880         if (h->ctlr && h->ctlr->ms_queued)
 881                 flush_workqueue(kmpath_rdacd);
 882
 883         spin_lock(&list_lock);
 884         if (h->ctlr)
 885                 kref_put(&h->ctlr->kref, release_controller);
 886         spin_unlock(&list_lock);
 887         kfree(h);
 888 }
 889
 890 static struct scsi_device_handler rdac_dh = {
 891         .name = RDAC_NAME,
 892         .module = THIS_MODULE,
 893         .prep_fn = rdac_prep_fn,
 894         .check_sense = rdac_check_sense,
 895         .attach = rdac_bus_attach,
 896         .detach = rdac_bus_detach,
 897         .activate = rdac_activate,
 898         .match = rdac_match,
 899 };
 900
 901 static int __init rdac_init(void)
 902 {
 903         int r;
 904
 905         r = scsi_register_device_handler(&rdac_dh);
 906         if (r != 0) {
 907                 printk(KERN_ERR "Failed to register scsi device handler.");
 908                 goto done;
 909         }
 910
 911         /*
 912          * Create workqueue to handle mode selects for rdac
 913          */
 914         kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd");
 915         if (!kmpath_rdacd) {
 916                 scsi_unregister_device_handler(&rdac_dh);
 917                 printk(KERN_ERR "kmpath_rdacd creation failed.\n");
 918
 919                 r = -EINVAL;
 920         }
 921 done:
 922         return r;
 923 }
 924
 925 static void __exit rdac_exit(void)
 926 {
 927         destroy_workqueue(kmpath_rdacd);
 928         scsi_unregister_device_handler(&rdac_dh);
 929 }
 930
 931 module_init(rdac_init);
 932 module_exit(rdac_exit);
 933
 934 MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver");
 935 MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
 936 MODULE_VERSION("01.00.0000.0000");
 937 MODULE_LICENSE("GPL");