xref: /linux/drivers/scsi/device_handler/scsi_dh_rdac.c (revision 9d9659b6c0ebf7dde65ebada4c67980818245913)
1 /*
2  * Engenio/LSI 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 struct rdac_controller {
132 	u8			subsys_id[SUBSYS_ID_LEN];
133 	u8			slot_id[SLOT_ID_LEN];
134 	int			use_ms10;
135 	struct kref		kref;
136 	struct list_head	node; /* list of all controllers */
137 	union			{
138 		struct rdac_pg_legacy legacy;
139 		struct rdac_pg_expanded expanded;
140 	} mode_select;
141 	u8	index;
142 	u8	array_name[ARRAY_LABEL_LEN];
143 	spinlock_t		ms_lock;
144 	int			ms_queued;
145 	struct work_struct	ms_work;
146 	struct scsi_device	*ms_sdev;
147 	struct list_head	ms_head;
148 };
149 
150 struct c8_inquiry {
151 	u8	peripheral_info;
152 	u8	page_code; /* 0xC8 */
153 	u8	reserved1;
154 	u8	page_len;
155 	u8	page_id[4]; /* "edid" */
156 	u8	reserved2[3];
157 	u8	vol_uniq_id_len;
158 	u8	vol_uniq_id[16];
159 	u8	vol_user_label_len;
160 	u8	vol_user_label[60];
161 	u8	array_uniq_id_len;
162 	u8	array_unique_id[16];
163 	u8	array_user_label_len;
164 	u8	array_user_label[60];
165 	u8	lun[8];
166 };
167 
168 struct c2_inquiry {
169 	u8	peripheral_info;
170 	u8	page_code;	/* 0xC2 */
171 	u8	reserved1;
172 	u8	page_len;
173 	u8	page_id[4];	/* "swr4" */
174 	u8	sw_version[3];
175 	u8	sw_date[3];
176 	u8	features_enabled;
177 	u8	max_lun_supported;
178 	u8	partitions[239]; /* Total allocation length should be 0xFF */
179 };
180 
181 struct rdac_dh_data {
182 	struct rdac_controller	*ctlr;
183 #define UNINITIALIZED_LUN	(1 << 8)
184 	unsigned		lun;
185 #define RDAC_STATE_ACTIVE	0
186 #define RDAC_STATE_PASSIVE	1
187 	unsigned char		state;
188 
189 #define RDAC_LUN_UNOWNED	0
190 #define RDAC_LUN_OWNED		1
191 #define RDAC_LUN_AVT		2
192 	char			lun_state;
193 	unsigned char		sense[SCSI_SENSE_BUFFERSIZE];
194 	union			{
195 		struct c2_inquiry c2;
196 		struct c4_inquiry c4;
197 		struct c8_inquiry c8;
198 		struct c9_inquiry c9;
199 	} inq;
200 };
201 
202 static const char *lun_state[] =
203 {
204 	"unowned",
205 	"owned",
206 	"owned (AVT mode)",
207 };
208 
209 struct rdac_queue_data {
210 	struct list_head	entry;
211 	struct rdac_dh_data	*h;
212 	activate_complete	callback_fn;
213 	void			*callback_data;
214 };
215 
216 static LIST_HEAD(ctlr_list);
217 static DEFINE_SPINLOCK(list_lock);
218 static struct workqueue_struct *kmpath_rdacd;
219 static void send_mode_select(struct work_struct *work);
220 
221 /*
222  * module parameter to enable rdac debug logging.
223  * 2 bits for each type of logging, only two types defined for now
224  * Can be enhanced if required at later point
225  */
226 static int rdac_logging = 1;
227 module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
228 MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, "
229 		"Default is 1 - failover logging enabled, "
230 		"set it to 0xF to enable all the logs");
231 
232 #define RDAC_LOG_FAILOVER	0
233 #define RDAC_LOG_SENSE		2
234 
235 #define RDAC_LOG_BITS		2
236 
237 #define RDAC_LOG_LEVEL(SHIFT)  \
238 	((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1))
239 
240 #define RDAC_LOG(SHIFT, sdev, f, arg...) \
241 do { \
242 	if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
243 		sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
244 } while (0);
245 
246 static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
247 {
248 	struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
249 	BUG_ON(scsi_dh_data == NULL);
250 	return ((struct rdac_dh_data *) scsi_dh_data->buf);
251 }
252 
253 static struct request *get_rdac_req(struct scsi_device *sdev,
254 			void *buffer, unsigned buflen, int rw)
255 {
256 	struct request *rq;
257 	struct request_queue *q = sdev->request_queue;
258 
259 	rq = blk_get_request(q, rw, GFP_NOIO);
260 
261 	if (!rq) {
262 		sdev_printk(KERN_INFO, sdev,
263 				"get_rdac_req: blk_get_request failed.\n");
264 		return NULL;
265 	}
266 
267 	if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
268 		blk_put_request(rq);
269 		sdev_printk(KERN_INFO, sdev,
270 				"get_rdac_req: blk_rq_map_kern failed.\n");
271 		return NULL;
272 	}
273 
274 	rq->cmd_type = REQ_TYPE_BLOCK_PC;
275 	rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
276 			 REQ_FAILFAST_DRIVER;
277 	rq->retries = RDAC_RETRIES;
278 	rq->timeout = RDAC_TIMEOUT;
279 
280 	return rq;
281 }
282 
283 static struct request *rdac_failover_get(struct scsi_device *sdev,
284 			struct rdac_dh_data *h, struct list_head *list)
285 {
286 	struct request *rq;
287 	struct rdac_mode_common *common;
288 	unsigned data_size;
289 	struct rdac_queue_data *qdata;
290 	u8 *lun_table;
291 
292 	if (h->ctlr->use_ms10) {
293 		struct rdac_pg_expanded *rdac_pg;
294 
295 		data_size = sizeof(struct rdac_pg_expanded);
296 		rdac_pg = &h->ctlr->mode_select.expanded;
297 		memset(rdac_pg, 0, data_size);
298 		common = &rdac_pg->common;
299 		rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40;
300 		rdac_pg->subpage_code = 0x1;
301 		rdac_pg->page_len[0] = 0x01;
302 		rdac_pg->page_len[1] = 0x28;
303 		lun_table = rdac_pg->lun_table;
304 	} else {
305 		struct rdac_pg_legacy *rdac_pg;
306 
307 		data_size = sizeof(struct rdac_pg_legacy);
308 		rdac_pg = &h->ctlr->mode_select.legacy;
309 		memset(rdac_pg, 0, data_size);
310 		common = &rdac_pg->common;
311 		rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER;
312 		rdac_pg->page_len = 0x68;
313 		lun_table = rdac_pg->lun_table;
314 	}
315 	common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
316 	common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
317 	common->rdac_options = RDAC_FORCED_QUIESENCE;
318 
319 	list_for_each_entry(qdata, list, entry) {
320 		lun_table[qdata->h->lun] = 0x81;
321 	}
322 
323 	/* get request for block layer packet command */
324 	rq = get_rdac_req(sdev, &h->ctlr->mode_select, data_size, WRITE);
325 	if (!rq)
326 		return NULL;
327 
328 	/* Prepare the command. */
329 	if (h->ctlr->use_ms10) {
330 		rq->cmd[0] = MODE_SELECT_10;
331 		rq->cmd[7] = data_size >> 8;
332 		rq->cmd[8] = data_size & 0xff;
333 	} else {
334 		rq->cmd[0] = MODE_SELECT;
335 		rq->cmd[4] = data_size;
336 	}
337 	rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
338 
339 	rq->sense = h->sense;
340 	memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
341 	rq->sense_len = 0;
342 
343 	return rq;
344 }
345 
346 static void release_controller(struct kref *kref)
347 {
348 	struct rdac_controller *ctlr;
349 	ctlr = container_of(kref, struct rdac_controller, kref);
350 
351 	flush_workqueue(kmpath_rdacd);
352 	spin_lock(&list_lock);
353 	list_del(&ctlr->node);
354 	spin_unlock(&list_lock);
355 	kfree(ctlr);
356 }
357 
358 static struct rdac_controller *get_controller(u8 *subsys_id, u8 *slot_id,
359 						char *array_name)
360 {
361 	struct rdac_controller *ctlr, *tmp;
362 
363 	spin_lock(&list_lock);
364 
365 	list_for_each_entry(tmp, &ctlr_list, node) {
366 		if ((memcmp(tmp->subsys_id, subsys_id, SUBSYS_ID_LEN) == 0) &&
367 			  (memcmp(tmp->slot_id, slot_id, SLOT_ID_LEN) == 0)) {
368 			kref_get(&tmp->kref);
369 			spin_unlock(&list_lock);
370 			return tmp;
371 		}
372 	}
373 	ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
374 	if (!ctlr)
375 		goto done;
376 
377 	/* initialize fields of controller */
378 	memcpy(ctlr->subsys_id, subsys_id, SUBSYS_ID_LEN);
379 	memcpy(ctlr->slot_id, slot_id, SLOT_ID_LEN);
380 	memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN);
381 
382 	/* update the controller index */
383 	if (slot_id[1] == 0x31)
384 		ctlr->index = 0;
385 	else
386 		ctlr->index = 1;
387 
388 	kref_init(&ctlr->kref);
389 	ctlr->use_ms10 = -1;
390 	ctlr->ms_queued = 0;
391 	ctlr->ms_sdev = NULL;
392 	spin_lock_init(&ctlr->ms_lock);
393 	INIT_WORK(&ctlr->ms_work, send_mode_select);
394 	INIT_LIST_HEAD(&ctlr->ms_head);
395 	list_add(&ctlr->node, &ctlr_list);
396 done:
397 	spin_unlock(&list_lock);
398 	return ctlr;
399 }
400 
401 static int submit_inquiry(struct scsi_device *sdev, int page_code,
402 			  unsigned int len, struct rdac_dh_data *h)
403 {
404 	struct request *rq;
405 	struct request_queue *q = sdev->request_queue;
406 	int err = SCSI_DH_RES_TEMP_UNAVAIL;
407 
408 	rq = get_rdac_req(sdev, &h->inq, len, READ);
409 	if (!rq)
410 		goto done;
411 
412 	/* Prepare the command. */
413 	rq->cmd[0] = INQUIRY;
414 	rq->cmd[1] = 1;
415 	rq->cmd[2] = page_code;
416 	rq->cmd[4] = len;
417 	rq->cmd_len = COMMAND_SIZE(INQUIRY);
418 
419 	rq->sense = h->sense;
420 	memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
421 	rq->sense_len = 0;
422 
423 	err = blk_execute_rq(q, NULL, rq, 1);
424 	if (err == -EIO)
425 		err = SCSI_DH_IO;
426 
427 	blk_put_request(rq);
428 done:
429 	return err;
430 }
431 
432 static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
433 			char *array_name)
434 {
435 	int err, i;
436 	struct c8_inquiry *inqp;
437 
438 	err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
439 	if (err == SCSI_DH_OK) {
440 		inqp = &h->inq.c8;
441 		if (inqp->page_code != 0xc8)
442 			return SCSI_DH_NOSYS;
443 		if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
444 		    inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
445 			return SCSI_DH_NOSYS;
446 		h->lun = inqp->lun[7]; /* Uses only the last byte */
447 
448 		for(i=0; i<ARRAY_LABEL_LEN-1; ++i)
449 			*(array_name+i) = inqp->array_user_label[(2*i)+1];
450 
451 		*(array_name+ARRAY_LABEL_LEN-1) = '\0';
452 	}
453 	return err;
454 }
455 
456 static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
457 {
458 	int err;
459 	struct c9_inquiry *inqp;
460 
461 	h->lun_state = RDAC_LUN_UNOWNED;
462 	h->state = RDAC_STATE_ACTIVE;
463 	err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
464 	if (err == SCSI_DH_OK) {
465 		inqp = &h->inq.c9;
466 		if ((inqp->avte_cvp >> 7) == 0x1) {
467 			/* LUN in AVT mode */
468 			sdev_printk(KERN_NOTICE, sdev,
469 				    "%s: AVT mode detected\n",
470 				    RDAC_NAME);
471 			h->lun_state = RDAC_LUN_AVT;
472 		} else if ((inqp->avte_cvp & 0x1) != 0) {
473 			/* LUN was owned by the controller */
474 			h->lun_state = RDAC_LUN_OWNED;
475 		}
476 	}
477 
478 	if (h->lun_state == RDAC_LUN_UNOWNED)
479 		h->state = RDAC_STATE_PASSIVE;
480 
481 	return err;
482 }
483 
484 static int initialize_controller(struct scsi_device *sdev,
485 				 struct rdac_dh_data *h, char *array_name)
486 {
487 	int err;
488 	struct c4_inquiry *inqp;
489 
490 	err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
491 	if (err == SCSI_DH_OK) {
492 		inqp = &h->inq.c4;
493 		h->ctlr = get_controller(inqp->subsys_id, inqp->slot_id,
494 					array_name);
495 		if (!h->ctlr)
496 			err = SCSI_DH_RES_TEMP_UNAVAIL;
497 	}
498 	return err;
499 }
500 
501 static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
502 {
503 	int err;
504 	struct c2_inquiry *inqp;
505 
506 	err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
507 	if (err == SCSI_DH_OK) {
508 		inqp = &h->inq.c2;
509 		/*
510 		 * If more than MODE6_MAX_LUN luns are supported, use
511 		 * mode select 10
512 		 */
513 		if (inqp->max_lun_supported >= MODE6_MAX_LUN)
514 			h->ctlr->use_ms10 = 1;
515 		else
516 			h->ctlr->use_ms10 = 0;
517 	}
518 	return err;
519 }
520 
521 static int mode_select_handle_sense(struct scsi_device *sdev,
522 					unsigned char *sensebuf)
523 {
524 	struct scsi_sense_hdr sense_hdr;
525 	int err = SCSI_DH_IO, ret;
526 	struct rdac_dh_data *h = get_rdac_data(sdev);
527 
528 	ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
529 	if (!ret)
530 		goto done;
531 
532 	switch (sense_hdr.sense_key) {
533 	case NO_SENSE:
534 	case ABORTED_COMMAND:
535 	case UNIT_ATTENTION:
536 		err = SCSI_DH_RETRY;
537 		break;
538 	case NOT_READY:
539 		if (sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x01)
540 			/* LUN Not Ready and is in the Process of Becoming
541 			 * Ready
542 			 */
543 			err = SCSI_DH_RETRY;
544 		break;
545 	case ILLEGAL_REQUEST:
546 		if (sense_hdr.asc == 0x91 && sense_hdr.ascq == 0x36)
547 			/*
548 			 * Command Lock contention
549 			 */
550 			err = SCSI_DH_RETRY;
551 		break;
552 	default:
553 		break;
554 	}
555 
556 	RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
557 		"MODE_SELECT returned with sense %02x/%02x/%02x",
558 		(char *) h->ctlr->array_name, h->ctlr->index,
559 		sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
560 
561 done:
562 	return err;
563 }
564 
565 static void send_mode_select(struct work_struct *work)
566 {
567 	struct rdac_controller *ctlr =
568 		container_of(work, struct rdac_controller, ms_work);
569 	struct request *rq;
570 	struct scsi_device *sdev = ctlr->ms_sdev;
571 	struct rdac_dh_data *h = get_rdac_data(sdev);
572 	struct request_queue *q = sdev->request_queue;
573 	int err, retry_cnt = RDAC_RETRY_COUNT;
574 	struct rdac_queue_data *tmp, *qdata;
575 	LIST_HEAD(list);
576 
577 	spin_lock(&ctlr->ms_lock);
578 	list_splice_init(&ctlr->ms_head, &list);
579 	ctlr->ms_queued = 0;
580 	ctlr->ms_sdev = NULL;
581 	spin_unlock(&ctlr->ms_lock);
582 
583 retry:
584 	err = SCSI_DH_RES_TEMP_UNAVAIL;
585 	rq = rdac_failover_get(sdev, h, &list);
586 	if (!rq)
587 		goto done;
588 
589 	RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
590 		"%s MODE_SELECT command",
591 		(char *) h->ctlr->array_name, h->ctlr->index,
592 		(retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying");
593 
594 	err = blk_execute_rq(q, NULL, rq, 1);
595 	blk_put_request(rq);
596 	if (err != SCSI_DH_OK) {
597 		err = mode_select_handle_sense(sdev, h->sense);
598 		if (err == SCSI_DH_RETRY && retry_cnt--)
599 			goto retry;
600 	}
601 	if (err == SCSI_DH_OK) {
602 		h->state = RDAC_STATE_ACTIVE;
603 		RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
604 				"MODE_SELECT completed",
605 				(char *) h->ctlr->array_name, h->ctlr->index);
606 	}
607 
608 done:
609 	list_for_each_entry_safe(qdata, tmp, &list, entry) {
610 		list_del(&qdata->entry);
611 		if (err == SCSI_DH_OK)
612 			qdata->h->state = RDAC_STATE_ACTIVE;
613 		if (qdata->callback_fn)
614 			qdata->callback_fn(qdata->callback_data, err);
615 		kfree(qdata);
616 	}
617 	return;
618 }
619 
620 static int queue_mode_select(struct scsi_device *sdev,
621 				activate_complete fn, void *data)
622 {
623 	struct rdac_queue_data *qdata;
624 	struct rdac_controller *ctlr;
625 
626 	qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
627 	if (!qdata)
628 		return SCSI_DH_RETRY;
629 
630 	qdata->h = get_rdac_data(sdev);
631 	qdata->callback_fn = fn;
632 	qdata->callback_data = data;
633 
634 	ctlr = qdata->h->ctlr;
635 	spin_lock(&ctlr->ms_lock);
636 	list_add_tail(&qdata->entry, &ctlr->ms_head);
637 	if (!ctlr->ms_queued) {
638 		ctlr->ms_queued = 1;
639 		ctlr->ms_sdev = sdev;
640 		queue_work(kmpath_rdacd, &ctlr->ms_work);
641 	}
642 	spin_unlock(&ctlr->ms_lock);
643 	return SCSI_DH_OK;
644 }
645 
646 static int rdac_activate(struct scsi_device *sdev,
647 			activate_complete fn, void *data)
648 {
649 	struct rdac_dh_data *h = get_rdac_data(sdev);
650 	int err = SCSI_DH_OK;
651 
652 	err = check_ownership(sdev, h);
653 	if (err != SCSI_DH_OK)
654 		goto done;
655 
656 	if (h->lun_state == RDAC_LUN_UNOWNED) {
657 		err = queue_mode_select(sdev, fn, data);
658 		if (err == SCSI_DH_OK)
659 			return 0;
660 	}
661 done:
662 	if (fn)
663 		fn(data, err);
664 	return 0;
665 }
666 
667 static int rdac_prep_fn(struct scsi_device *sdev, struct request *req)
668 {
669 	struct rdac_dh_data *h = get_rdac_data(sdev);
670 	int ret = BLKPREP_OK;
671 
672 	if (h->state != RDAC_STATE_ACTIVE) {
673 		ret = BLKPREP_KILL;
674 		req->cmd_flags |= REQ_QUIET;
675 	}
676 	return ret;
677 
678 }
679 
680 static int rdac_check_sense(struct scsi_device *sdev,
681 				struct scsi_sense_hdr *sense_hdr)
682 {
683 	struct rdac_dh_data *h = get_rdac_data(sdev);
684 
685 	RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, "
686 			"I/O returned with sense %02x/%02x/%02x",
687 			(char *) h->ctlr->array_name, h->ctlr->index,
688 			sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq);
689 
690 	switch (sense_hdr->sense_key) {
691 	case NOT_READY:
692 		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01)
693 			/* LUN Not Ready - Logical Unit Not Ready and is in
694 			* the process of becoming ready
695 			* Just retry.
696 			*/
697 			return ADD_TO_MLQUEUE;
698 		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
699 			/* LUN Not Ready - Storage firmware incompatible
700 			 * Manual code synchonisation required.
701 			 *
702 			 * Nothing we can do here. Try to bypass the path.
703 			 */
704 			return SUCCESS;
705 		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1)
706 			/* LUN Not Ready - Quiescense in progress
707 			 *
708 			 * Just retry and wait.
709 			 */
710 			return ADD_TO_MLQUEUE;
711 		if (sense_hdr->asc == 0xA1  && sense_hdr->ascq == 0x02)
712 			/* LUN Not Ready - Quiescense in progress
713 			 * or has been achieved
714 			 * Just retry.
715 			 */
716 			return ADD_TO_MLQUEUE;
717 		break;
718 	case ILLEGAL_REQUEST:
719 		if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) {
720 			/* Invalid Request - Current Logical Unit Ownership.
721 			 * Controller is not the current owner of the LUN,
722 			 * Fail the path, so that the other path be used.
723 			 */
724 			h->state = RDAC_STATE_PASSIVE;
725 			return SUCCESS;
726 		}
727 		break;
728 	case UNIT_ATTENTION:
729 		if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
730 			/*
731 			 * Power On, Reset, or Bus Device Reset, just retry.
732 			 */
733 			return ADD_TO_MLQUEUE;
734 		if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02)
735 			/*
736 			 * Quiescence in progress , just retry.
737 			 */
738 			return ADD_TO_MLQUEUE;
739 		break;
740 	}
741 	/* success just means we do not care what scsi-ml does */
742 	return SCSI_RETURN_NOT_HANDLED;
743 }
744 
745 static const struct scsi_dh_devlist rdac_dev_list[] = {
746 	{"IBM", "1722"},
747 	{"IBM", "1724"},
748 	{"IBM", "1726"},
749 	{"IBM", "1742"},
750 	{"IBM", "1745"},
751 	{"IBM", "1746"},
752 	{"IBM", "1814"},
753 	{"IBM", "1815"},
754 	{"IBM", "1818"},
755 	{"IBM", "3526"},
756 	{"SGI", "TP9400"},
757 	{"SGI", "TP9500"},
758 	{"SGI", "IS"},
759 	{"STK", "OPENstorage D280"},
760 	{"SUN", "CSM200_R"},
761 	{"SUN", "LCSM100_I"},
762 	{"SUN", "LCSM100_S"},
763 	{"SUN", "LCSM100_E"},
764 	{"SUN", "LCSM100_F"},
765 	{"DELL", "MD3000"},
766 	{"DELL", "MD3000i"},
767 	{"DELL", "MD32xx"},
768 	{"DELL", "MD32xxi"},
769 	{"DELL", "MD36xxi"},
770 	{"DELL", "MD36xxf"},
771 	{"LSI", "INF-01-00"},
772 	{"ENGENIO", "INF-01-00"},
773 	{"STK", "FLEXLINE 380"},
774 	{"SUN", "CSM100_R_FC"},
775 	{"SUN", "STK6580_6780"},
776 	{"SUN", "SUN_6180"},
777 	{NULL, NULL},
778 };
779 
780 static int rdac_bus_attach(struct scsi_device *sdev);
781 static void rdac_bus_detach(struct scsi_device *sdev);
782 
783 static struct scsi_device_handler rdac_dh = {
784 	.name = RDAC_NAME,
785 	.module = THIS_MODULE,
786 	.devlist = rdac_dev_list,
787 	.prep_fn = rdac_prep_fn,
788 	.check_sense = rdac_check_sense,
789 	.attach = rdac_bus_attach,
790 	.detach = rdac_bus_detach,
791 	.activate = rdac_activate,
792 };
793 
794 static int rdac_bus_attach(struct scsi_device *sdev)
795 {
796 	struct scsi_dh_data *scsi_dh_data;
797 	struct rdac_dh_data *h;
798 	unsigned long flags;
799 	int err;
800 	char array_name[ARRAY_LABEL_LEN];
801 
802 	scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
803 			       + sizeof(*h) , GFP_KERNEL);
804 	if (!scsi_dh_data) {
805 		sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
806 			    RDAC_NAME);
807 		return 0;
808 	}
809 
810 	scsi_dh_data->scsi_dh = &rdac_dh;
811 	h = (struct rdac_dh_data *) scsi_dh_data->buf;
812 	h->lun = UNINITIALIZED_LUN;
813 	h->state = RDAC_STATE_ACTIVE;
814 
815 	err = get_lun_info(sdev, h, array_name);
816 	if (err != SCSI_DH_OK)
817 		goto failed;
818 
819 	err = initialize_controller(sdev, h, array_name);
820 	if (err != SCSI_DH_OK)
821 		goto failed;
822 
823 	err = check_ownership(sdev, h);
824 	if (err != SCSI_DH_OK)
825 		goto clean_ctlr;
826 
827 	err = set_mode_select(sdev, h);
828 	if (err != SCSI_DH_OK)
829 		goto clean_ctlr;
830 
831 	if (!try_module_get(THIS_MODULE))
832 		goto clean_ctlr;
833 
834 	spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
835 	sdev->scsi_dh_data = scsi_dh_data;
836 	spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
837 
838 	sdev_printk(KERN_NOTICE, sdev,
839 		    "%s: LUN %d (%s)\n",
840 		    RDAC_NAME, h->lun, lun_state[(int)h->lun_state]);
841 
842 	return 0;
843 
844 clean_ctlr:
845 	kref_put(&h->ctlr->kref, release_controller);
846 
847 failed:
848 	kfree(scsi_dh_data);
849 	sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
850 		    RDAC_NAME);
851 	return -EINVAL;
852 }
853 
854 static void rdac_bus_detach( struct scsi_device *sdev )
855 {
856 	struct scsi_dh_data *scsi_dh_data;
857 	struct rdac_dh_data *h;
858 	unsigned long flags;
859 
860 	spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
861 	scsi_dh_data = sdev->scsi_dh_data;
862 	sdev->scsi_dh_data = NULL;
863 	spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
864 
865 	h = (struct rdac_dh_data *) scsi_dh_data->buf;
866 	if (h->ctlr)
867 		kref_put(&h->ctlr->kref, release_controller);
868 	kfree(scsi_dh_data);
869 	module_put(THIS_MODULE);
870 	sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", RDAC_NAME);
871 }
872 
873 
874 
875 static int __init rdac_init(void)
876 {
877 	int r;
878 
879 	r = scsi_register_device_handler(&rdac_dh);
880 	if (r != 0) {
881 		printk(KERN_ERR "Failed to register scsi device handler.");
882 		goto done;
883 	}
884 
885 	/*
886 	 * Create workqueue to handle mode selects for rdac
887 	 */
888 	kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd");
889 	if (!kmpath_rdacd) {
890 		scsi_unregister_device_handler(&rdac_dh);
891 		printk(KERN_ERR "kmpath_rdacd creation failed.\n");
892 	}
893 done:
894 	return r;
895 }
896 
897 static void __exit rdac_exit(void)
898 {
899 	destroy_workqueue(kmpath_rdacd);
900 	scsi_unregister_device_handler(&rdac_dh);
901 }
902 
903 module_init(rdac_init);
904 module_exit(rdac_exit);
905 
906 MODULE_DESCRIPTION("Multipath LSI/Engenio RDAC driver");
907 MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
908 MODULE_VERSION("01.00.0000.0000");
909 MODULE_LICENSE("GPL");
910