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