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 struct list_head dh_list; 169 }; 170 171 struct c2_inquiry { 172 u8 peripheral_info; 173 u8 page_code; /* 0xC2 */ 174 u8 reserved1; 175 u8 page_len; 176 u8 page_id[4]; /* "swr4" */ 177 u8 sw_version[3]; 178 u8 sw_date[3]; 179 u8 features_enabled; 180 u8 max_lun_supported; 181 u8 partitions[239]; /* Total allocation length should be 0xFF */ 182 }; 183 184 struct rdac_dh_data { 185 struct list_head node; 186 struct rdac_controller *ctlr; 187 struct scsi_device *sdev; 188 #define UNINITIALIZED_LUN (1 << 8) 189 unsigned lun; 190 191 #define RDAC_MODE 0 192 #define RDAC_MODE_AVT 1 193 #define RDAC_MODE_IOSHIP 2 194 unsigned char mode; 195 196 #define RDAC_STATE_ACTIVE 0 197 #define RDAC_STATE_PASSIVE 1 198 unsigned char state; 199 200 #define RDAC_LUN_UNOWNED 0 201 #define RDAC_LUN_OWNED 1 202 char lun_state; 203 204 #define RDAC_PREFERRED 0 205 #define RDAC_NON_PREFERRED 1 206 char preferred; 207 208 union { 209 struct c2_inquiry c2; 210 struct c4_inquiry c4; 211 struct c8_inquiry c8; 212 struct c9_inquiry c9; 213 } inq; 214 }; 215 216 static const char *mode[] = { 217 "RDAC", 218 "AVT", 219 "IOSHIP", 220 }; 221 static const char *lun_state[] = 222 { 223 "unowned", 224 "owned", 225 }; 226 227 struct rdac_queue_data { 228 struct list_head entry; 229 struct rdac_dh_data *h; 230 activate_complete callback_fn; 231 void *callback_data; 232 }; 233 234 static LIST_HEAD(ctlr_list); 235 static DEFINE_SPINLOCK(list_lock); 236 static struct workqueue_struct *kmpath_rdacd; 237 static void send_mode_select(struct work_struct *work); 238 239 /* 240 * module parameter to enable rdac debug logging. 241 * 2 bits for each type of logging, only two types defined for now 242 * Can be enhanced if required at later point 243 */ 244 static int rdac_logging = 1; 245 module_param(rdac_logging, int, S_IRUGO|S_IWUSR); 246 MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, " 247 "Default is 1 - failover logging enabled, " 248 "set it to 0xF to enable all the logs"); 249 250 #define RDAC_LOG_FAILOVER 0 251 #define RDAC_LOG_SENSE 2 252 253 #define RDAC_LOG_BITS 2 254 255 #define RDAC_LOG_LEVEL(SHIFT) \ 256 ((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1)) 257 258 #define RDAC_LOG(SHIFT, sdev, f, arg...) \ 259 do { \ 260 if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \ 261 sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \ 262 } while (0); 263 264 static unsigned int rdac_failover_get(struct rdac_controller *ctlr, 265 struct list_head *list, 266 unsigned char *cdb) 267 { 268 struct rdac_mode_common *common; 269 unsigned data_size; 270 struct rdac_queue_data *qdata; 271 u8 *lun_table; 272 273 if (ctlr->use_ms10) { 274 struct rdac_pg_expanded *rdac_pg; 275 276 data_size = sizeof(struct rdac_pg_expanded); 277 rdac_pg = &ctlr->mode_select.expanded; 278 memset(rdac_pg, 0, data_size); 279 common = &rdac_pg->common; 280 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40; 281 rdac_pg->subpage_code = 0x1; 282 rdac_pg->page_len[0] = 0x01; 283 rdac_pg->page_len[1] = 0x28; 284 lun_table = rdac_pg->lun_table; 285 } else { 286 struct rdac_pg_legacy *rdac_pg; 287 288 data_size = sizeof(struct rdac_pg_legacy); 289 rdac_pg = &ctlr->mode_select.legacy; 290 memset(rdac_pg, 0, data_size); 291 common = &rdac_pg->common; 292 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER; 293 rdac_pg->page_len = 0x68; 294 lun_table = rdac_pg->lun_table; 295 } 296 common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS; 297 common->quiescence_timeout = RDAC_QUIESCENCE_TIME; 298 common->rdac_options = RDAC_FORCED_QUIESENCE; 299 300 list_for_each_entry(qdata, list, entry) { 301 lun_table[qdata->h->lun] = 0x81; 302 } 303 304 /* Prepare the command. */ 305 if (ctlr->use_ms10) { 306 cdb[0] = MODE_SELECT_10; 307 cdb[7] = data_size >> 8; 308 cdb[8] = data_size & 0xff; 309 } else { 310 cdb[0] = MODE_SELECT; 311 cdb[4] = data_size; 312 } 313 314 return data_size; 315 } 316 317 static void release_controller(struct kref *kref) 318 { 319 struct rdac_controller *ctlr; 320 ctlr = container_of(kref, struct rdac_controller, kref); 321 322 list_del(&ctlr->node); 323 kfree(ctlr); 324 } 325 326 static struct rdac_controller *get_controller(int index, char *array_name, 327 u8 *array_id, struct scsi_device *sdev) 328 { 329 struct rdac_controller *ctlr, *tmp; 330 331 list_for_each_entry(tmp, &ctlr_list, node) { 332 if ((memcmp(tmp->array_id, array_id, UNIQUE_ID_LEN) == 0) && 333 (tmp->index == index) && 334 (tmp->host == sdev->host)) { 335 kref_get(&tmp->kref); 336 return tmp; 337 } 338 } 339 ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC); 340 if (!ctlr) 341 return NULL; 342 343 /* initialize fields of controller */ 344 memcpy(ctlr->array_id, array_id, UNIQUE_ID_LEN); 345 ctlr->index = index; 346 ctlr->host = sdev->host; 347 memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN); 348 349 kref_init(&ctlr->kref); 350 ctlr->use_ms10 = -1; 351 ctlr->ms_queued = 0; 352 ctlr->ms_sdev = NULL; 353 spin_lock_init(&ctlr->ms_lock); 354 INIT_WORK(&ctlr->ms_work, send_mode_select); 355 INIT_LIST_HEAD(&ctlr->ms_head); 356 list_add(&ctlr->node, &ctlr_list); 357 INIT_LIST_HEAD(&ctlr->dh_list); 358 359 return ctlr; 360 } 361 362 static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h, 363 char *array_name, u8 *array_id) 364 { 365 int err = SCSI_DH_IO, i; 366 struct c8_inquiry *inqp = &h->inq.c8; 367 368 if (!scsi_get_vpd_page(sdev, 0xC8, (unsigned char *)inqp, 369 sizeof(struct c8_inquiry))) { 370 if (inqp->page_code != 0xc8) 371 return SCSI_DH_NOSYS; 372 if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' || 373 inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd') 374 return SCSI_DH_NOSYS; 375 h->lun = inqp->lun[7]; /* Uses only the last byte */ 376 377 for(i=0; i<ARRAY_LABEL_LEN-1; ++i) 378 *(array_name+i) = inqp->array_user_label[(2*i)+1]; 379 380 *(array_name+ARRAY_LABEL_LEN-1) = '\0'; 381 memset(array_id, 0, UNIQUE_ID_LEN); 382 memcpy(array_id, inqp->array_unique_id, inqp->array_uniq_id_len); 383 err = SCSI_DH_OK; 384 } 385 return err; 386 } 387 388 static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h) 389 { 390 int err = SCSI_DH_IO, access_state; 391 struct rdac_dh_data *tmp; 392 struct c9_inquiry *inqp = &h->inq.c9; 393 394 h->state = RDAC_STATE_ACTIVE; 395 if (!scsi_get_vpd_page(sdev, 0xC9, (unsigned char *)inqp, 396 sizeof(struct c9_inquiry))) { 397 /* detect the operating mode */ 398 if ((inqp->avte_cvp >> 5) & 0x1) 399 h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */ 400 else if (inqp->avte_cvp >> 7) 401 h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */ 402 else 403 h->mode = RDAC_MODE; /* LUN in RDAC mode */ 404 405 /* Update ownership */ 406 if (inqp->avte_cvp & 0x1) { 407 h->lun_state = RDAC_LUN_OWNED; 408 access_state = SCSI_ACCESS_STATE_OPTIMAL; 409 } else { 410 h->lun_state = RDAC_LUN_UNOWNED; 411 if (h->mode == RDAC_MODE) { 412 h->state = RDAC_STATE_PASSIVE; 413 access_state = SCSI_ACCESS_STATE_STANDBY; 414 } else 415 access_state = SCSI_ACCESS_STATE_ACTIVE; 416 } 417 418 /* Update path prio*/ 419 if (inqp->path_prio & 0x1) { 420 h->preferred = RDAC_PREFERRED; 421 access_state |= SCSI_ACCESS_STATE_PREFERRED; 422 } else 423 h->preferred = RDAC_NON_PREFERRED; 424 rcu_read_lock(); 425 list_for_each_entry_rcu(tmp, &h->ctlr->dh_list, node) { 426 /* h->sdev should always be valid */ 427 BUG_ON(!tmp->sdev); 428 tmp->sdev->access_state = access_state; 429 } 430 rcu_read_unlock(); 431 err = SCSI_DH_OK; 432 } 433 434 return err; 435 } 436 437 static int initialize_controller(struct scsi_device *sdev, 438 struct rdac_dh_data *h, char *array_name, u8 *array_id) 439 { 440 int err = SCSI_DH_IO, index; 441 struct c4_inquiry *inqp = &h->inq.c4; 442 443 if (!scsi_get_vpd_page(sdev, 0xC4, (unsigned char *)inqp, 444 sizeof(struct c4_inquiry))) { 445 /* get the controller index */ 446 if (inqp->slot_id[1] == 0x31) 447 index = 0; 448 else 449 index = 1; 450 451 spin_lock(&list_lock); 452 h->ctlr = get_controller(index, array_name, array_id, sdev); 453 if (!h->ctlr) 454 err = SCSI_DH_RES_TEMP_UNAVAIL; 455 else { 456 h->sdev = sdev; 457 list_add_rcu(&h->node, &h->ctlr->dh_list); 458 } 459 spin_unlock(&list_lock); 460 err = SCSI_DH_OK; 461 } 462 return err; 463 } 464 465 static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h) 466 { 467 int err = SCSI_DH_IO; 468 struct c2_inquiry *inqp = &h->inq.c2; 469 470 if (!scsi_get_vpd_page(sdev, 0xC2, (unsigned char *)inqp, 471 sizeof(struct c2_inquiry))) { 472 /* 473 * If more than MODE6_MAX_LUN luns are supported, use 474 * mode select 10 475 */ 476 if (inqp->max_lun_supported >= MODE6_MAX_LUN) 477 h->ctlr->use_ms10 = 1; 478 else 479 h->ctlr->use_ms10 = 0; 480 err = SCSI_DH_OK; 481 } 482 return err; 483 } 484 485 static int mode_select_handle_sense(struct scsi_device *sdev, 486 struct scsi_sense_hdr *sense_hdr) 487 { 488 int err = SCSI_DH_IO; 489 struct rdac_dh_data *h = sdev->handler_data; 490 491 if (!scsi_sense_valid(sense_hdr)) 492 goto done; 493 494 switch (sense_hdr->sense_key) { 495 case NO_SENSE: 496 case ABORTED_COMMAND: 497 case UNIT_ATTENTION: 498 err = SCSI_DH_RETRY; 499 break; 500 case NOT_READY: 501 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01) 502 /* LUN Not Ready and is in the Process of Becoming 503 * Ready 504 */ 505 err = SCSI_DH_RETRY; 506 break; 507 case ILLEGAL_REQUEST: 508 if (sense_hdr->asc == 0x91 && sense_hdr->ascq == 0x36) 509 /* 510 * Command Lock contention 511 */ 512 err = SCSI_DH_IMM_RETRY; 513 break; 514 default: 515 break; 516 } 517 518 RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, " 519 "MODE_SELECT returned with sense %02x/%02x/%02x", 520 (char *) h->ctlr->array_name, h->ctlr->index, 521 sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq); 522 523 done: 524 return err; 525 } 526 527 static void send_mode_select(struct work_struct *work) 528 { 529 struct rdac_controller *ctlr = 530 container_of(work, struct rdac_controller, ms_work); 531 struct scsi_device *sdev = ctlr->ms_sdev; 532 struct rdac_dh_data *h = sdev->handler_data; 533 int rc, err, retry_cnt = RDAC_RETRY_COUNT; 534 struct rdac_queue_data *tmp, *qdata; 535 LIST_HEAD(list); 536 unsigned char cdb[MAX_COMMAND_SIZE]; 537 struct scsi_sense_hdr sshdr; 538 unsigned int data_size; 539 blk_opf_t opf = REQ_OP_DRV_OUT | REQ_FAILFAST_DEV | 540 REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER; 541 const struct scsi_exec_args exec_args = { 542 .sshdr = &sshdr, 543 }; 544 545 spin_lock(&ctlr->ms_lock); 546 list_splice_init(&ctlr->ms_head, &list); 547 ctlr->ms_queued = 0; 548 ctlr->ms_sdev = NULL; 549 spin_unlock(&ctlr->ms_lock); 550 551 retry: 552 memset(cdb, 0, sizeof(cdb)); 553 554 data_size = rdac_failover_get(ctlr, &list, cdb); 555 556 RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, " 557 "%s MODE_SELECT command", 558 (char *) h->ctlr->array_name, h->ctlr->index, 559 (retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying"); 560 561 rc = scsi_execute_cmd(sdev, cdb, opf, &h->ctlr->mode_select, data_size, 562 RDAC_TIMEOUT * HZ, RDAC_RETRIES, &exec_args); 563 if (!rc) { 564 h->state = RDAC_STATE_ACTIVE; 565 RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, " 566 "MODE_SELECT completed", 567 (char *) h->ctlr->array_name, h->ctlr->index); 568 err = SCSI_DH_OK; 569 } else if (rc < 0) { 570 err = SCSI_DH_IO; 571 } else { 572 err = mode_select_handle_sense(sdev, &sshdr); 573 if (err == SCSI_DH_RETRY && retry_cnt--) 574 goto retry; 575 if (err == SCSI_DH_IMM_RETRY) 576 goto retry; 577 } 578 579 list_for_each_entry_safe(qdata, tmp, &list, entry) { 580 list_del(&qdata->entry); 581 if (err == SCSI_DH_OK) 582 qdata->h->state = RDAC_STATE_ACTIVE; 583 if (qdata->callback_fn) 584 qdata->callback_fn(qdata->callback_data, err); 585 kfree(qdata); 586 } 587 return; 588 } 589 590 static int queue_mode_select(struct scsi_device *sdev, 591 activate_complete fn, void *data) 592 { 593 struct rdac_queue_data *qdata; 594 struct rdac_controller *ctlr; 595 596 qdata = kzalloc(sizeof(*qdata), GFP_KERNEL); 597 if (!qdata) 598 return SCSI_DH_RETRY; 599 600 qdata->h = sdev->handler_data; 601 qdata->callback_fn = fn; 602 qdata->callback_data = data; 603 604 ctlr = qdata->h->ctlr; 605 spin_lock(&ctlr->ms_lock); 606 list_add_tail(&qdata->entry, &ctlr->ms_head); 607 if (!ctlr->ms_queued) { 608 ctlr->ms_queued = 1; 609 ctlr->ms_sdev = sdev; 610 queue_work(kmpath_rdacd, &ctlr->ms_work); 611 } 612 spin_unlock(&ctlr->ms_lock); 613 return SCSI_DH_OK; 614 } 615 616 static int rdac_activate(struct scsi_device *sdev, 617 activate_complete fn, void *data) 618 { 619 struct rdac_dh_data *h = sdev->handler_data; 620 int err = SCSI_DH_OK; 621 int act = 0; 622 623 err = check_ownership(sdev, h); 624 if (err != SCSI_DH_OK) 625 goto done; 626 627 switch (h->mode) { 628 case RDAC_MODE: 629 if (h->lun_state == RDAC_LUN_UNOWNED) 630 act = 1; 631 break; 632 case RDAC_MODE_IOSHIP: 633 if ((h->lun_state == RDAC_LUN_UNOWNED) && 634 (h->preferred == RDAC_PREFERRED)) 635 act = 1; 636 break; 637 default: 638 break; 639 } 640 641 if (act) { 642 err = queue_mode_select(sdev, fn, data); 643 if (err == SCSI_DH_OK) 644 return 0; 645 } 646 done: 647 if (fn) 648 fn(data, err); 649 return 0; 650 } 651 652 static blk_status_t rdac_prep_fn(struct scsi_device *sdev, struct request *req) 653 { 654 struct rdac_dh_data *h = sdev->handler_data; 655 656 if (h->state != RDAC_STATE_ACTIVE) { 657 req->rq_flags |= RQF_QUIET; 658 return BLK_STS_IOERR; 659 } 660 661 return BLK_STS_OK; 662 } 663 664 static enum scsi_disposition rdac_check_sense(struct scsi_device *sdev, 665 struct scsi_sense_hdr *sense_hdr) 666 { 667 struct rdac_dh_data *h = sdev->handler_data; 668 669 RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, " 670 "I/O returned with sense %02x/%02x/%02x", 671 (char *) h->ctlr->array_name, h->ctlr->index, 672 sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq); 673 674 switch (sense_hdr->sense_key) { 675 case NOT_READY: 676 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01) 677 /* LUN Not Ready - Logical Unit Not Ready and is in 678 * the process of becoming ready 679 * Just retry. 680 */ 681 return ADD_TO_MLQUEUE; 682 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81) 683 /* LUN Not Ready - Storage firmware incompatible 684 * Manual code synchonisation required. 685 * 686 * Nothing we can do here. Try to bypass the path. 687 */ 688 return SUCCESS; 689 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1) 690 /* LUN Not Ready - Quiescense in progress 691 * 692 * Just retry and wait. 693 */ 694 return ADD_TO_MLQUEUE; 695 if (sense_hdr->asc == 0xA1 && sense_hdr->ascq == 0x02) 696 /* LUN Not Ready - Quiescense in progress 697 * or has been achieved 698 * Just retry. 699 */ 700 return ADD_TO_MLQUEUE; 701 break; 702 case ILLEGAL_REQUEST: 703 if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) { 704 /* Invalid Request - Current Logical Unit Ownership. 705 * Controller is not the current owner of the LUN, 706 * Fail the path, so that the other path be used. 707 */ 708 h->state = RDAC_STATE_PASSIVE; 709 return SUCCESS; 710 } 711 break; 712 case UNIT_ATTENTION: 713 if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) 714 /* 715 * Power On, Reset, or Bus Device Reset, just retry. 716 */ 717 return ADD_TO_MLQUEUE; 718 if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02) 719 /* 720 * Quiescence in progress , just retry. 721 */ 722 return ADD_TO_MLQUEUE; 723 break; 724 } 725 /* success just means we do not care what scsi-ml does */ 726 return SCSI_RETURN_NOT_HANDLED; 727 } 728 729 static int rdac_bus_attach(struct scsi_device *sdev) 730 { 731 struct rdac_dh_data *h; 732 int err; 733 char array_name[ARRAY_LABEL_LEN]; 734 char array_id[UNIQUE_ID_LEN]; 735 736 h = kzalloc(sizeof(*h) , GFP_KERNEL); 737 if (!h) 738 return SCSI_DH_NOMEM; 739 h->lun = UNINITIALIZED_LUN; 740 h->state = RDAC_STATE_ACTIVE; 741 742 err = get_lun_info(sdev, h, array_name, array_id); 743 if (err != SCSI_DH_OK) 744 goto failed; 745 746 err = initialize_controller(sdev, h, array_name, array_id); 747 if (err != SCSI_DH_OK) 748 goto failed; 749 750 err = check_ownership(sdev, h); 751 if (err != SCSI_DH_OK) 752 goto clean_ctlr; 753 754 err = set_mode_select(sdev, h); 755 if (err != SCSI_DH_OK) 756 goto clean_ctlr; 757 758 sdev_printk(KERN_NOTICE, sdev, 759 "%s: LUN %d (%s) (%s)\n", 760 RDAC_NAME, h->lun, mode[(int)h->mode], 761 lun_state[(int)h->lun_state]); 762 763 sdev->handler_data = h; 764 return SCSI_DH_OK; 765 766 clean_ctlr: 767 spin_lock(&list_lock); 768 kref_put(&h->ctlr->kref, release_controller); 769 spin_unlock(&list_lock); 770 771 failed: 772 kfree(h); 773 return err; 774 } 775 776 static void rdac_bus_detach( struct scsi_device *sdev ) 777 { 778 struct rdac_dh_data *h = sdev->handler_data; 779 780 if (h->ctlr && h->ctlr->ms_queued) 781 flush_workqueue(kmpath_rdacd); 782 783 spin_lock(&list_lock); 784 if (h->ctlr) { 785 list_del_rcu(&h->node); 786 kref_put(&h->ctlr->kref, release_controller); 787 } 788 spin_unlock(&list_lock); 789 sdev->handler_data = NULL; 790 synchronize_rcu(); 791 kfree(h); 792 } 793 794 static struct scsi_device_handler rdac_dh = { 795 .name = RDAC_NAME, 796 .module = THIS_MODULE, 797 .prep_fn = rdac_prep_fn, 798 .check_sense = rdac_check_sense, 799 .attach = rdac_bus_attach, 800 .detach = rdac_bus_detach, 801 .activate = rdac_activate, 802 }; 803 804 static int __init rdac_init(void) 805 { 806 int r; 807 808 r = scsi_register_device_handler(&rdac_dh); 809 if (r != 0) { 810 printk(KERN_ERR "Failed to register scsi device handler."); 811 goto done; 812 } 813 814 /* 815 * Create workqueue to handle mode selects for rdac 816 */ 817 kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd"); 818 if (!kmpath_rdacd) { 819 scsi_unregister_device_handler(&rdac_dh); 820 printk(KERN_ERR "kmpath_rdacd creation failed.\n"); 821 822 r = -EINVAL; 823 } 824 done: 825 return r; 826 } 827 828 static void __exit rdac_exit(void) 829 { 830 destroy_workqueue(kmpath_rdacd); 831 scsi_unregister_device_handler(&rdac_dh); 832 } 833 834 module_init(rdac_init); 835 module_exit(rdac_exit); 836 837 MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver"); 838 MODULE_AUTHOR("Mike Christie, Chandra Seetharaman"); 839 MODULE_VERSION("01.00.0000.0000"); 840 MODULE_LICENSE("GPL"); 841