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         list_del(&ctlr->node);
 368         kfree(ctlr);
 369 }
 370
 371 static struct rdac_controller *get_controller(int index, char *array_name,
 372                         u8 *array_id, struct scsi_device *sdev)
 373 {
 374         struct rdac_controller *ctlr, *tmp;
 375
 376         list_for_each_entry(tmp, &ctlr_list, node) {
 377                 if ((memcmp(tmp->array_id, array_id, UNIQUE_ID_LEN) == 0) &&
 378                           (tmp->index == index) &&
 379                           (tmp->host == sdev->host)) {
 380                         kref_get(&tmp->kref);
 381                         return tmp;
 382                 }
 383         }
 384         ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
 385         if (!ctlr)
 386                 return NULL;
 387
 388         /* initialize fields of controller */
 389         memcpy(ctlr->array_id, array_id, UNIQUE_ID_LEN);
 390         ctlr->index = index;
 391         ctlr->host = sdev->host;
 392         memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN);
 393
 394         kref_init(&ctlr->kref);
 395         ctlr->use_ms10 = -1;
 396         ctlr->ms_queued = 0;
 397         ctlr->ms_sdev = NULL;
 398         spin_lock_init(&ctlr->ms_lock);
 399         INIT_WORK(&ctlr->ms_work, send_mode_select);
 400         INIT_LIST_HEAD(&ctlr->ms_head);
 401         list_add(&ctlr->node, &ctlr_list);
 402
 403         return ctlr;
 404 }
 405
 406 static int submit_inquiry(struct scsi_device *sdev, int page_code,
 407                           unsigned int len, struct rdac_dh_data *h)
 408 {
 409         struct request *rq;
 410         struct request_queue *q = sdev->request_queue;
 411         int err = SCSI_DH_RES_TEMP_UNAVAIL;
 412
 413         rq = get_rdac_req(sdev, &h->inq, len, READ);
 414         if (!rq)
 415                 goto done;
 416
 417         /* Prepare the command. */
 418         rq->cmd[0] = INQUIRY;
 419         rq->cmd[1] = 1;
 420         rq->cmd[2] = page_code;
 421         rq->cmd[4] = len;
 422         rq->cmd_len = COMMAND_SIZE(INQUIRY);
 423
 424         rq->sense = h->sense;
 425         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
 426         rq->sense_len = 0;
 427
 428         err = blk_execute_rq(q, NULL, rq, 1);
 429         if (err == -EIO)
 430                 err = SCSI_DH_IO;
 431
 432         blk_put_request(rq);
 433 done:
 434         return err;
 435 }
 436
 437 static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
 438                         char *array_name, u8 *array_id)
 439 {
 440         int err, i;
 441         struct c8_inquiry *inqp;
 442
 443         err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
 444         if (err == SCSI_DH_OK) {
 445                 inqp = &h->inq.c8;
 446                 if (inqp->page_code != 0xc8)
 447                         return SCSI_DH_NOSYS;
 448                 if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
 449                     inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
 450                         return SCSI_DH_NOSYS;
 451                 h->lun = inqp->lun[7]; /* Uses only the last byte */
 452
 453                 for(i=0; i<ARRAY_LABEL_LEN-1; ++i)
 454                         *(array_name+i) = inqp->array_user_label[(2*i)+1];
 455
 456                 *(array_name+ARRAY_LABEL_LEN-1) = '\0';
 457                 memset(array_id, 0, UNIQUE_ID_LEN);
 458                 memcpy(array_id, inqp->array_unique_id, inqp->array_uniq_id_len);
 459         }
 460         return err;
 461 }
 462
 463 static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
 464 {
 465         int err;
 466         struct c9_inquiry *inqp;
 467
 468         h->state = RDAC_STATE_ACTIVE;
 469         err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
 470         if (err == SCSI_DH_OK) {
 471                 inqp = &h->inq.c9;
 472                 /* detect the operating mode */
 473                 if ((inqp->avte_cvp >> 5) & 0x1)
 474                         h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */
 475                 else if (inqp->avte_cvp >> 7)
 476                         h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */
 477                 else
 478                         h->mode = RDAC_MODE; /* LUN in RDAC mode */
 479
 480                 /* Update ownership */
 481                 if (inqp->avte_cvp & 0x1)
 482                         h->lun_state = RDAC_LUN_OWNED;
 483                 else {
 484                         h->lun_state = RDAC_LUN_UNOWNED;
 485                         if (h->mode == RDAC_MODE)
 486                                 h->state = RDAC_STATE_PASSIVE;
 487                 }
 488
 489                 /* Update path prio*/
 490                 if (inqp->path_prio & 0x1)
 491                         h->preferred = RDAC_PREFERRED;
 492                 else
 493                         h->preferred = RDAC_NON_PREFERRED;
 494         }
 495
 496         return err;
 497 }
 498
 499 static int initialize_controller(struct scsi_device *sdev,
 500                 struct rdac_dh_data *h, char *array_name, u8 *array_id)
 501 {
 502         int err, index;
 503         struct c4_inquiry *inqp;
 504
 505         err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
 506         if (err == SCSI_DH_OK) {
 507                 inqp = &h->inq.c4;
 508                 /* get the controller index */
 509                 if (inqp->slot_id[1] == 0x31)
 510                         index = 0;
 511                 else
 512                         index = 1;
 513
 514                 spin_lock(&list_lock);
 515                 h->ctlr = get_controller(index, array_name, array_id, sdev);
 516                 if (!h->ctlr)
 517                         err = SCSI_DH_RES_TEMP_UNAVAIL;
 518                 spin_unlock(&list_lock);
 519         }
 520         return err;
 521 }
 522
 523 static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
 524 {
 525         int err;
 526         struct c2_inquiry *inqp;
 527
 528         err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
 529         if (err == SCSI_DH_OK) {
 530                 inqp = &h->inq.c2;
 531                 /*
 532                  * If more than MODE6_MAX_LUN luns are supported, use
 533                  * mode select 10
 534                  */
 535                 if (inqp->max_lun_supported >= MODE6_MAX_LUN)
 536                         h->ctlr->use_ms10 = 1;
 537                 else
 538                         h->ctlr->use_ms10 = 0;
 539         }
 540         return err;
 541 }
 542
 543 static int mode_select_handle_sense(struct scsi_device *sdev,
 544                                         unsigned char *sensebuf)
 545 {
 546         struct scsi_sense_hdr sense_hdr;
 547         int err = SCSI_DH_IO, ret;
 548         struct rdac_dh_data *h = get_rdac_data(sdev);
 549
 550         ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
 551         if (!ret)
 552                 goto done;
 553
 554         switch (sense_hdr.sense_key) {
 555         case NO_SENSE:
 556         case ABORTED_COMMAND:
 557         case UNIT_ATTENTION:
 558                 err = SCSI_DH_RETRY;
 559                 break;
 560         case NOT_READY:
 561                 if (sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x01)
 562                         /* LUN Not Ready and is in the Process of Becoming
 563                          * Ready
 564                          */
 565                         err = SCSI_DH_RETRY;
 566                 break;
 567         case ILLEGAL_REQUEST:
 568                 if (sense_hdr.asc == 0x91 && sense_hdr.ascq == 0x36)
 569                         /*
 570                          * Command Lock contention
 571                          */
 572                         err = SCSI_DH_RETRY;
 573                 break;
 574         default:
 575                 break;
 576         }
 577
 578         RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 579                 "MODE_SELECT returned with sense %02x/%02x/%02x",
 580                 (char *) h->ctlr->array_name, h->ctlr->index,
 581                 sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
 582
 583 done:
 584         return err;
 585 }
 586
 587 static void send_mode_select(struct work_struct *work)
 588 {
 589         struct rdac_controller *ctlr =
 590                 container_of(work, struct rdac_controller, ms_work);
 591         struct request *rq;
 592         struct scsi_device *sdev = ctlr->ms_sdev;
 593         struct rdac_dh_data *h = get_rdac_data(sdev);
 594         struct request_queue *q = sdev->request_queue;
 595         int err, retry_cnt = RDAC_RETRY_COUNT;
 596         struct rdac_queue_data *tmp, *qdata;
 597         LIST_HEAD(list);
 598
 599         spin_lock(&ctlr->ms_lock);
 600         list_splice_init(&ctlr->ms_head, &list);
 601         ctlr->ms_queued = 0;
 602         ctlr->ms_sdev = NULL;
 603         spin_unlock(&ctlr->ms_lock);
 604
 605 retry:
 606         err = SCSI_DH_RES_TEMP_UNAVAIL;
 607         rq = rdac_failover_get(sdev, h, &list);
 608         if (!rq)
 609                 goto done;
 610
 611         RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 612                 "%s MODE_SELECT command",
 613                 (char *) h->ctlr->array_name, h->ctlr->index,
 614                 (retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying");
 615
 616         err = blk_execute_rq(q, NULL, rq, 1);
 617         blk_put_request(rq);
 618         if (err != SCSI_DH_OK) {
 619                 err = mode_select_handle_sense(sdev, h->sense);
 620                 if (err == SCSI_DH_RETRY && retry_cnt--)
 621                         goto retry;
 622         }
 623         if (err == SCSI_DH_OK) {
 624                 h->state = RDAC_STATE_ACTIVE;
 625                 RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
 626                                 "MODE_SELECT completed",
 627                                 (char *) h->ctlr->array_name, h->ctlr->index);
 628         }
 629
 630 done:
 631         list_for_each_entry_safe(qdata, tmp, &list, entry) {
 632                 list_del(&qdata->entry);
 633                 if (err == SCSI_DH_OK)
 634                         qdata->h->state = RDAC_STATE_ACTIVE;
 635                 if (qdata->callback_fn)
 636                         qdata->callback_fn(qdata->callback_data, err);
 637                 kfree(qdata);
 638         }
 639         return;
 640 }
 641
 642 static int queue_mode_select(struct scsi_device *sdev,
 643                                 activate_complete fn, void *data)
 644 {
 645         struct rdac_queue_data *qdata;
 646         struct rdac_controller *ctlr;
 647
 648         qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
 649         if (!qdata)
 650                 return SCSI_DH_RETRY;
 651
 652         qdata->h = get_rdac_data(sdev);
 653         qdata->callback_fn = fn;
 654         qdata->callback_data = data;
 655
 656         ctlr = qdata->h->ctlr;
 657         spin_lock(&ctlr->ms_lock);
 658         list_add_tail(&qdata->entry, &ctlr->ms_head);
 659         if (!ctlr->ms_queued) {
 660                 ctlr->ms_queued = 1;
 661                 ctlr->ms_sdev = sdev;
 662                 queue_work(kmpath_rdacd, &ctlr->ms_work);
 663         }
 664         spin_unlock(&ctlr->ms_lock);
 665         return SCSI_DH_OK;
 666 }
 667
 668 static int rdac_activate(struct scsi_device *sdev,
 669                         activate_complete fn, void *data)
 670 {
 671         struct rdac_dh_data *h = get_rdac_data(sdev);
 672         int err = SCSI_DH_OK;
 673         int act = 0;
 674
 675         err = check_ownership(sdev, h);
 676         if (err != SCSI_DH_OK)
 677                 goto done;
 678
 679         switch (h->mode) {
 680         case RDAC_MODE:
 681                 if (h->lun_state == RDAC_LUN_UNOWNED)
 682                         act = 1;
 683                 break;
 684         case RDAC_MODE_IOSHIP:
 685                 if ((h->lun_state == RDAC_LUN_UNOWNED) &&
 686                     (h->preferred == RDAC_PREFERRED))
 687                         act = 1;
 688                 break;
 689         default:
 690                 break;
 691         }
 692
 693         if (act) {
 694                 err = queue_mode_select(sdev, fn, data);
 695                 if (err == SCSI_DH_OK)
 696                         return 0;
 697         }
 698 done:
 699         if (fn)
 700                 fn(data, err);
 701         return 0;
 702 }
 703
 704 static int rdac_prep_fn(struct scsi_device *sdev, struct request *req)
 705 {
 706         struct rdac_dh_data *h = get_rdac_data(sdev);
 707         int ret = BLKPREP_OK;
 708
 709         if (h->state != RDAC_STATE_ACTIVE) {
 710                 ret = BLKPREP_KILL;
 711                 req->cmd_flags |= REQ_QUIET;
 712         }
 713         return ret;
 714
 715 }
 716
 717 static int rdac_check_sense(struct scsi_device *sdev,
 718                                 struct scsi_sense_hdr *sense_hdr)
 719 {
 720         struct rdac_dh_data *h = get_rdac_data(sdev);
 721
 722         RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, "
 723                         "I/O returned with sense %02x/%02x/%02x",
 724                         (char *) h->ctlr->array_name, h->ctlr->index,
 725                         sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq);
 726
 727         switch (sense_hdr->sense_key) {
 728         case NOT_READY:
 729                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01)
 730                         /* LUN Not Ready - Logical Unit Not Ready and is in
 731                         * the process of becoming ready
 732                         * Just retry.
 733                         */
 734                         return ADD_TO_MLQUEUE;
 735                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
 736                         /* LUN Not Ready - Storage firmware incompatible
 737                          * Manual code synchonisation required.
 738                          *
 739                          * Nothing we can do here. Try to bypass the path.
 740                          */
 741                         return SUCCESS;
 742                 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1)
 743                         /* LUN Not Ready - Quiescense in progress
 744                          *
 745                          * Just retry and wait.
 746                          */
 747                         return ADD_TO_MLQUEUE;
 748                 if (sense_hdr->asc == 0xA1  && sense_hdr->ascq == 0x02)
 749                         /* LUN Not Ready - Quiescense in progress
 750                          * or has been achieved
 751                          * Just retry.
 752                          */
 753                         return ADD_TO_MLQUEUE;
 754                 break;
 755         case ILLEGAL_REQUEST:
 756                 if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) {
 757                         /* Invalid Request - Current Logical Unit Ownership.
 758                          * Controller is not the current owner of the LUN,
 759                          * Fail the path, so that the other path be used.
 760                          */
 761                         h->state = RDAC_STATE_PASSIVE;
 762                         return SUCCESS;
 763                 }
 764                 break;
 765         case UNIT_ATTENTION:
 766                 if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
 767                         /*
 768                          * Power On, Reset, or Bus Device Reset, just retry.
 769                          */
 770                         return ADD_TO_MLQUEUE;
 771                 if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02)
 772                         /*
 773                          * Quiescence in progress , just retry.
 774                          */
 775                         return ADD_TO_MLQUEUE;
 776                 break;
 777         }
 778         /* success just means we do not care what scsi-ml does */
 779         return SCSI_RETURN_NOT_HANDLED;
 780 }
 781
 782 static const struct scsi_dh_devlist rdac_dev_list[] = {
 783         {"IBM", "1722"},
 784         {"IBM", "1724"},
 785         {"IBM", "1726"},
 786         {"IBM", "1742"},
 787         {"IBM", "1745"},
 788         {"IBM", "1746"},
 789         {"IBM", "1814"},
 790         {"IBM", "1815"},
 791         {"IBM", "1818"},
 792         {"IBM", "3526"},
 793         {"SGI", "TP9"},
 794         {"SGI", "IS"},
 795         {"STK", "OPENstorage D280"},
 796         {"STK", "FLEXLINE 380"},
 797         {"SUN", "CSM"},
 798         {"SUN", "LCSM100"},
 799         {"SUN", "STK6580_6780"},
 800         {"SUN", "SUN_6180"},
 801         {"SUN", "ArrayStorage"},
 802         {"DELL", "MD3"},
 803         {"NETAPP", "INF-01-00"},
 804         {"LSI", "INF-01-00"},
 805         {"ENGENIO", "INF-01-00"},
 806         {NULL, NULL},
 807 };
 808
 809 static bool rdac_match(struct scsi_device *sdev)
 810 {
 811         int i;
 812
 813         if (scsi_device_tpgs(sdev))
 814                 return false;
 815
 816         for (i = 0; rdac_dev_list[i].vendor; i++) {
 817                 if (!strncmp(sdev->vendor, rdac_dev_list[i].vendor,
 818                         strlen(rdac_dev_list[i].vendor)) &&
 819                     !strncmp(sdev->model, rdac_dev_list[i].model,
 820                         strlen(rdac_dev_list[i].model))) {
 821                         return true;
 822                 }
 823         }
 824         return false;
 825 }
 826
 827 static int rdac_bus_attach(struct scsi_device *sdev);
 828 static void rdac_bus_detach(struct scsi_device *sdev);
 829
 830 static struct scsi_device_handler rdac_dh = {
 831         .name = RDAC_NAME,
 832         .module = THIS_MODULE,
 833         .devlist = rdac_dev_list,
 834         .prep_fn = rdac_prep_fn,
 835         .check_sense = rdac_check_sense,
 836         .attach = rdac_bus_attach,
 837         .detach = rdac_bus_detach,
 838         .activate = rdac_activate,
 839         .match = rdac_match,
 840 };
 841
 842 static int rdac_bus_attach(struct scsi_device *sdev)
 843 {
 844         struct scsi_dh_data *scsi_dh_data;
 845         struct rdac_dh_data *h;
 846         unsigned long flags;
 847         int err;
 848         char array_name[ARRAY_LABEL_LEN];
 849         char array_id[UNIQUE_ID_LEN];
 850
 851         scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
 852                                + sizeof(*h) , GFP_KERNEL);
 853         if (!scsi_dh_data) {
 854                 sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
 855                             RDAC_NAME);
 856                 return -ENOMEM;
 857         }
 858
 859         scsi_dh_data->scsi_dh = &rdac_dh;
 860         h = (struct rdac_dh_data *) scsi_dh_data->buf;
 861         h->lun = UNINITIALIZED_LUN;
 862         h->state = RDAC_STATE_ACTIVE;
 863
 864         err = get_lun_info(sdev, h, array_name, array_id);
 865         if (err != SCSI_DH_OK)
 866                 goto failed;
 867
 868         err = initialize_controller(sdev, h, array_name, array_id);
 869         if (err != SCSI_DH_OK)
 870                 goto failed;
 871
 872         err = check_ownership(sdev, h);
 873         if (err != SCSI_DH_OK)
 874                 goto clean_ctlr;
 875
 876         err = set_mode_select(sdev, h);
 877         if (err != SCSI_DH_OK)
 878                 goto clean_ctlr;
 879
 880         if (!try_module_get(THIS_MODULE))
 881                 goto clean_ctlr;
 882
 883         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
 884         sdev->scsi_dh_data = scsi_dh_data;
 885         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
 886
 887         sdev_printk(KERN_NOTICE, sdev,
 888                     "%s: LUN %d (%s) (%s)\n",
 889                     RDAC_NAME, h->lun, mode[(int)h->mode],
 890                     lun_state[(int)h->lun_state]);
 891
 892         return 0;
 893
 894 clean_ctlr:
 895         spin_lock(&list_lock);
 896         kref_put(&h->ctlr->kref, release_controller);
 897         spin_unlock(&list_lock);
 898
 899 failed:
 900         kfree(scsi_dh_data);
 901         sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
 902                     RDAC_NAME);
 903         return -EINVAL;
 904 }
 905
 906 static void rdac_bus_detach( struct scsi_device *sdev )
 907 {
 908         struct scsi_dh_data *scsi_dh_data;
 909         struct rdac_dh_data *h;
 910         unsigned long flags;
 911
 912         scsi_dh_data = sdev->scsi_dh_data;
 913         h = (struct rdac_dh_data *) scsi_dh_data->buf;
 914         if (h->ctlr && h->ctlr->ms_queued)
 915                 flush_workqueue(kmpath_rdacd);
 916
 917         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
 918         sdev->scsi_dh_data = NULL;
 919         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
 920
 921         spin_lock(&list_lock);
 922         if (h->ctlr)
 923                 kref_put(&h->ctlr->kref, release_controller);
 924         spin_unlock(&list_lock);
 925         kfree(scsi_dh_data);
 926         module_put(THIS_MODULE);
 927         sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", RDAC_NAME);
 928 }
 929
 930
 931
 932 static int __init rdac_init(void)
 933 {
 934         int r;
 935
 936         r = scsi_register_device_handler(&rdac_dh);
 937         if (r != 0) {
 938                 printk(KERN_ERR "Failed to register scsi device handler.");
 939                 goto done;
 940         }
 941
 942         /*
 943          * Create workqueue to handle mode selects for rdac
 944          */
 945         kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd");
 946         if (!kmpath_rdacd) {
 947                 scsi_unregister_device_handler(&rdac_dh);
 948                 printk(KERN_ERR "kmpath_rdacd creation failed.\n");
 949
 950                 r = -EINVAL;
 951         }
 952 done:
 953         return r;
 954 }
 955
 956 static void __exit rdac_exit(void)
 957 {
 958         destroy_workqueue(kmpath_rdacd);
 959         scsi_unregister_device_handler(&rdac_dh);
 960 }
 961
 962 module_init(rdac_init);
 963 module_exit(rdac_exit);
 964
 965 MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver");
 966 MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
 967 MODULE_VERSION("01.00.0000.0000");
 968 MODULE_LICENSE("GPL");