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
58struct rdac_mode_6_hdr {
59 u8 data_len;
60 u8 medium_type;
61 u8 device_params;
62 u8 block_desc_len;
63};
64
65struct 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
73struct 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
82struct 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
94struct 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
105struct 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
120struct 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
133struct 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
151struct 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
171struct 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
184struct 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
216static const char *mode[] = {
217 "RDAC",
218 "AVT",
219 "IOSHIP",
220};
221static const char *lun_state[] =
222{
223 "unowned",
224 "owned",
225};
226
227struct 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
234static LIST_HEAD(ctlr_list);
235static DEFINE_SPINLOCK(list_lock);
236static struct workqueue_struct *kmpath_rdacd;
237static 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 */
244static int rdac_logging = 1;
245module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
246MODULE_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...) \
259do { \
260 if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
261 sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
262} while (0);
263
264static 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
317static 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(entry: &ctlr->node);
323 kfree(objp: ctlr);
324}
325
326static 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(p: tmp->array_id, q: array_id, UNIQUE_ID_LEN) == 0) &&
333 (tmp->index == index) &&
334 (tmp->host == sdev->host)) {
335 kref_get(kref: &tmp->kref);
336 return tmp;
337 }
338 }
339 ctlr = kmalloc(size: 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(kref: &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(list: &ctlr->ms_head);
356 list_add(new: &ctlr->node, head: &ctlr_list);
357 INIT_LIST_HEAD(list: &ctlr->dh_list);
358
359 return ctlr;
360}
361
362static 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, page: 0xC8, buf: (unsigned char *)inqp,
369 buf_len: 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
388static 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, page: 0xC9, buf: (unsigned char *)inqp,
396 buf_len: 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
437static 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, page: 0xC4, buf: (unsigned char *)inqp,
444 buf_len: 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(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(new: &h->node, head: &h->ctlr->dh_list);
458 }
459 spin_unlock(lock: &list_lock);
460 err = SCSI_DH_OK;
461 }
462 return err;
463}
464
465static 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, page: 0xC2, buf: (unsigned char *)inqp,
471 buf_len: 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
485static 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(sshdr: 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
523done:
524 return err;
525}
526
527static 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(lock: &ctlr->ms_lock);
546 list_splice_init(list: &ctlr->ms_head, head: &list);
547 ctlr->ms_queued = 0;
548 ctlr->ms_sdev = NULL;
549 spin_unlock(lock: &ctlr->ms_lock);
550
551 retry:
552 memset(cdb, 0, sizeof(cdb));
553
554 data_size = rdac_failover_get(ctlr, list: &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, cmd: cdb, opf, buffer: &h->ctlr->mode_select, bufflen: data_size,
562 RDAC_TIMEOUT * HZ, RDAC_RETRIES, args: &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, sense_hdr: &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(entry: &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(objp: qdata);
586 }
587 return;
588}
589
590static 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(size: 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(lock: &ctlr->ms_lock);
606 list_add_tail(new: &qdata->entry, head: &ctlr->ms_head);
607 if (!ctlr->ms_queued) {
608 ctlr->ms_queued = 1;
609 ctlr->ms_sdev = sdev;
610 queue_work(wq: kmpath_rdacd, work: &ctlr->ms_work);
611 }
612 spin_unlock(lock: &ctlr->ms_lock);
613 return SCSI_DH_OK;
614}
615
616static 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 }
646done:
647 if (fn)
648 fn(data, err);
649 return 0;
650}
651
652static 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
664static 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
729static 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(size: 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
766clean_ctlr:
767 spin_lock(lock: &list_lock);
768 kref_put(kref: &h->ctlr->kref, release: release_controller);
769 spin_unlock(lock: &list_lock);
770
771failed:
772 kfree(objp: h);
773 return err;
774}
775
776static 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(lock: &list_lock);
784 if (h->ctlr) {
785 list_del_rcu(entry: &h->node);
786 kref_put(kref: &h->ctlr->kref, release: release_controller);
787 }
788 spin_unlock(lock: &list_lock);
789 sdev->handler_data = NULL;
790 synchronize_rcu();
791 kfree(objp: h);
792}
793
794static 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
804static int __init rdac_init(void)
805{
806 int r;
807
808 r = scsi_register_device_handler(scsi_dh: &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(scsi_dh: &rdac_dh);
820 printk(KERN_ERR "kmpath_rdacd creation failed.\n");
821
822 r = -EINVAL;
823 }
824done:
825 return r;
826}
827
828static void __exit rdac_exit(void)
829{
830 destroy_workqueue(wq: kmpath_rdacd);
831 scsi_unregister_device_handler(scsi_dh: &rdac_dh);
832}
833
834module_init(rdac_init);
835module_exit(rdac_exit);
836
837MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver");
838MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
839MODULE_VERSION("01.00.0000.0000");
840MODULE_LICENSE("GPL");
841

source code of linux/drivers/scsi/device_handler/scsi_dh_rdac.c