Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[pandora-kernel.git] / drivers / scsi / device_handler / scsi_dh_rdac.c
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
186 #define RDAC_MODE               0
187 #define RDAC_MODE_AVT           1
188 #define RDAC_MODE_IOSHIP        2
189         unsigned char           mode;
190
191 #define RDAC_STATE_ACTIVE       0
192 #define RDAC_STATE_PASSIVE      1
193         unsigned char           state;
194
195 #define RDAC_LUN_UNOWNED        0
196 #define RDAC_LUN_OWNED          1
197         char                    lun_state;
198
199 #define RDAC_PREFERRED          0
200 #define RDAC_NON_PREFERRED      1
201         char                    preferred;
202
203         unsigned char           sense[SCSI_SENSE_BUFFERSIZE];
204         union                   {
205                 struct c2_inquiry c2;
206                 struct c4_inquiry c4;
207                 struct c8_inquiry c8;
208                 struct c9_inquiry c9;
209         } inq;
210 };
211
212 static const char *mode[] = {
213         "RDAC",
214         "AVT",
215         "IOSHIP",
216 };
217 static const char *lun_state[] =
218 {
219         "unowned",
220         "owned",
221 };
222
223 struct rdac_queue_data {
224         struct list_head        entry;
225         struct rdac_dh_data     *h;
226         activate_complete       callback_fn;
227         void                    *callback_data;
228 };
229
230 static LIST_HEAD(ctlr_list);
231 static DEFINE_SPINLOCK(list_lock);
232 static struct workqueue_struct *kmpath_rdacd;
233 static void send_mode_select(struct work_struct *work);
234
235 /*
236  * module parameter to enable rdac debug logging.
237  * 2 bits for each type of logging, only two types defined for now
238  * Can be enhanced if required at later point
239  */
240 static int rdac_logging = 1;
241 module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
242 MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, "
243                 "Default is 1 - failover logging enabled, "
244                 "set it to 0xF to enable all the logs");
245
246 #define RDAC_LOG_FAILOVER       0
247 #define RDAC_LOG_SENSE          2
248
249 #define RDAC_LOG_BITS           2
250
251 #define RDAC_LOG_LEVEL(SHIFT)  \
252         ((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1))
253
254 #define RDAC_LOG(SHIFT, sdev, f, arg...) \
255 do { \
256         if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
257                 sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
258 } while (0);
259
260 static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
261 {
262         struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
263         BUG_ON(scsi_dh_data == NULL);
264         return ((struct rdac_dh_data *) scsi_dh_data->buf);
265 }
266
267 static struct request *get_rdac_req(struct scsi_device *sdev,
268                         void *buffer, unsigned buflen, int rw)
269 {
270         struct request *rq;
271         struct request_queue *q = sdev->request_queue;
272
273         rq = blk_get_request(q, rw, GFP_NOIO);
274
275         if (!rq) {
276                 sdev_printk(KERN_INFO, sdev,
277                                 "get_rdac_req: blk_get_request failed.\n");
278                 return NULL;
279         }
280
281         if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
282                 blk_put_request(rq);
283                 sdev_printk(KERN_INFO, sdev,
284                                 "get_rdac_req: blk_rq_map_kern failed.\n");
285                 return NULL;
286         }
287
288         rq->cmd_type = REQ_TYPE_BLOCK_PC;
289         rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
290                          REQ_FAILFAST_DRIVER;
291         rq->retries = RDAC_RETRIES;
292         rq->timeout = RDAC_TIMEOUT;
293
294         return rq;
295 }
296
297 static struct request *rdac_failover_get(struct scsi_device *sdev,
298                         struct rdac_dh_data *h, struct list_head *list)
299 {
300         struct request *rq;
301         struct rdac_mode_common *common;
302         unsigned data_size;
303         struct rdac_queue_data *qdata;
304         u8 *lun_table;
305
306         if (h->ctlr->use_ms10) {
307                 struct rdac_pg_expanded *rdac_pg;
308
309                 data_size = sizeof(struct rdac_pg_expanded);
310                 rdac_pg = &h->ctlr->mode_select.expanded;
311                 memset(rdac_pg, 0, data_size);
312                 common = &rdac_pg->common;
313                 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40;
314                 rdac_pg->subpage_code = 0x1;
315                 rdac_pg->page_len[0] = 0x01;
316                 rdac_pg->page_len[1] = 0x28;
317                 lun_table = rdac_pg->lun_table;
318         } else {
319                 struct rdac_pg_legacy *rdac_pg;
320
321                 data_size = sizeof(struct rdac_pg_legacy);
322                 rdac_pg = &h->ctlr->mode_select.legacy;
323                 memset(rdac_pg, 0, data_size);
324                 common = &rdac_pg->common;
325                 rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER;
326                 rdac_pg->page_len = 0x68;
327                 lun_table = rdac_pg->lun_table;
328         }
329         common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
330         common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
331         common->rdac_options = RDAC_FORCED_QUIESENCE;
332
333         list_for_each_entry(qdata, list, entry) {
334                 lun_table[qdata->h->lun] = 0x81;
335         }
336
337         /* get request for block layer packet command */
338         rq = get_rdac_req(sdev, &h->ctlr->mode_select, data_size, WRITE);
339         if (!rq)
340                 return NULL;
341
342         /* Prepare the command. */
343         if (h->ctlr->use_ms10) {
344                 rq->cmd[0] = MODE_SELECT_10;
345                 rq->cmd[7] = data_size >> 8;
346                 rq->cmd[8] = data_size & 0xff;
347         } else {
348                 rq->cmd[0] = MODE_SELECT;
349                 rq->cmd[4] = data_size;
350         }
351         rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
352
353         rq->sense = h->sense;
354         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
355         rq->sense_len = 0;
356
357         return rq;
358 }
359
360 static void release_controller(struct kref *kref)
361 {
362         struct rdac_controller *ctlr;
363         ctlr = container_of(kref, struct rdac_controller, kref);
364
365         flush_workqueue(kmpath_rdacd);
366         spin_lock(&list_lock);
367         list_del(&ctlr->node);
368         spin_unlock(&list_lock);
369         kfree(ctlr);
370 }
371
372 static struct rdac_controller *get_controller(u8 *subsys_id, u8 *slot_id,
373                                                 char *array_name)
374 {
375         struct rdac_controller *ctlr, *tmp;
376
377         spin_lock(&list_lock);
378
379         list_for_each_entry(tmp, &ctlr_list, node) {
380                 if ((memcmp(tmp->subsys_id, subsys_id, SUBSYS_ID_LEN) == 0) &&
381                           (memcmp(tmp->slot_id, slot_id, SLOT_ID_LEN) == 0)) {
382                         kref_get(&tmp->kref);
383                         spin_unlock(&list_lock);
384                         return tmp;
385                 }
386         }
387         ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
388         if (!ctlr)
389                 goto done;
390
391         /* initialize fields of controller */
392         memcpy(ctlr->subsys_id, subsys_id, SUBSYS_ID_LEN);
393         memcpy(ctlr->slot_id, slot_id, SLOT_ID_LEN);
394         memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN);
395
396         /* update the controller index */
397         if (slot_id[1] == 0x31)
398                 ctlr->index = 0;
399         else
400                 ctlr->index = 1;
401
402         kref_init(&ctlr->kref);
403         ctlr->use_ms10 = -1;
404         ctlr->ms_queued = 0;
405         ctlr->ms_sdev = NULL;
406         spin_lock_init(&ctlr->ms_lock);
407         INIT_WORK(&ctlr->ms_work, send_mode_select);
408         INIT_LIST_HEAD(&ctlr->ms_head);
409         list_add(&ctlr->node, &ctlr_list);
410 done:
411         spin_unlock(&list_lock);
412         return ctlr;
413 }
414
415 static int submit_inquiry(struct scsi_device *sdev, int page_code,
416                           unsigned int len, struct rdac_dh_data *h)
417 {
418         struct request *rq;
419         struct request_queue *q = sdev->request_queue;
420         int err = SCSI_DH_RES_TEMP_UNAVAIL;
421
422         rq = get_rdac_req(sdev, &h->inq, len, READ);
423         if (!rq)
424                 goto done;
425
426         /* Prepare the command. */
427         rq->cmd[0] = INQUIRY;
428         rq->cmd[1] = 1;
429         rq->cmd[2] = page_code;
430         rq->cmd[4] = len;
431         rq->cmd_len = COMMAND_SIZE(INQUIRY);
432
433         rq->sense = h->sense;
434         memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
435         rq->sense_len = 0;
436
437         err = blk_execute_rq(q, NULL, rq, 1);
438         if (err == -EIO)
439                 err = SCSI_DH_IO;
440
441         blk_put_request(rq);
442 done:
443         return err;
444 }
445
446 static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h,
447                         char *array_name)
448 {
449         int err, i;
450         struct c8_inquiry *inqp;
451
452         err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
453         if (err == SCSI_DH_OK) {
454                 inqp = &h->inq.c8;
455                 if (inqp->page_code != 0xc8)
456                         return SCSI_DH_NOSYS;
457                 if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
458                     inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
459                         return SCSI_DH_NOSYS;
460                 h->lun = inqp->lun[7]; /* Uses only the last byte */
461
462                 for(i=0; i<ARRAY_LABEL_LEN-1; ++i)
463                         *(array_name+i) = inqp->array_user_label[(2*i)+1];
464
465                 *(array_name+ARRAY_LABEL_LEN-1) = '\0';
466         }
467         return err;
468 }
469
470 static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
471 {
472         int err;
473         struct c9_inquiry *inqp;
474
475         h->state = RDAC_STATE_ACTIVE;
476         err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
477         if (err == SCSI_DH_OK) {
478                 inqp = &h->inq.c9;
479                 /* detect the operating mode */
480                 if ((inqp->avte_cvp >> 5) & 0x1)
481                         h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */
482                 else if (inqp->avte_cvp >> 7)
483                         h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */
484                 else
485                         h->mode = RDAC_MODE; /* LUN in RDAC mode */
486
487                 /* Update ownership */
488                 if (inqp->avte_cvp & 0x1)
489                         h->lun_state = RDAC_LUN_OWNED;
490                 else {
491                         h->lun_state = RDAC_LUN_UNOWNED;
492                         if (h->mode == RDAC_MODE)
493                                 h->state = RDAC_STATE_PASSIVE;
494                 }
495
496                 /* Update path prio*/
497                 if (inqp->path_prio & 0x1)
498                         h->preferred = RDAC_PREFERRED;
499                 else
500                         h->preferred = RDAC_NON_PREFERRED;
501         }
502
503         return err;
504 }
505
506 static int initialize_controller(struct scsi_device *sdev,
507                                  struct rdac_dh_data *h, char *array_name)
508 {
509         int err;
510         struct c4_inquiry *inqp;
511
512         err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
513         if (err == SCSI_DH_OK) {
514                 inqp = &h->inq.c4;
515                 h->ctlr = get_controller(inqp->subsys_id, inqp->slot_id,
516                                         array_name);
517                 if (!h->ctlr)
518                         err = SCSI_DH_RES_TEMP_UNAVAIL;
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", "TP9400"},
794         {"SGI", "TP9500"},
795         {"SGI", "IS"},
796         {"STK", "OPENstorage D280"},
797         {"SUN", "CSM200_R"},
798         {"SUN", "LCSM100_I"},
799         {"SUN", "LCSM100_S"},
800         {"SUN", "LCSM100_E"},
801         {"SUN", "LCSM100_F"},
802         {"DELL", "MD3000"},
803         {"DELL", "MD3000i"},
804         {"DELL", "MD32xx"},
805         {"DELL", "MD32xxi"},
806         {"DELL", "MD36xxi"},
807         {"DELL", "MD36xxf"},
808         {"LSI", "INF-01-00"},
809         {"ENGENIO", "INF-01-00"},
810         {"STK", "FLEXLINE 380"},
811         {"SUN", "CSM100_R_FC"},
812         {"SUN", "STK6580_6780"},
813         {"SUN", "SUN_6180"},
814         {NULL, NULL},
815 };
816
817 static int rdac_bus_attach(struct scsi_device *sdev);
818 static void rdac_bus_detach(struct scsi_device *sdev);
819
820 static struct scsi_device_handler rdac_dh = {
821         .name = RDAC_NAME,
822         .module = THIS_MODULE,
823         .devlist = rdac_dev_list,
824         .prep_fn = rdac_prep_fn,
825         .check_sense = rdac_check_sense,
826         .attach = rdac_bus_attach,
827         .detach = rdac_bus_detach,
828         .activate = rdac_activate,
829 };
830
831 static int rdac_bus_attach(struct scsi_device *sdev)
832 {
833         struct scsi_dh_data *scsi_dh_data;
834         struct rdac_dh_data *h;
835         unsigned long flags;
836         int err;
837         char array_name[ARRAY_LABEL_LEN];
838
839         scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
840                                + sizeof(*h) , GFP_KERNEL);
841         if (!scsi_dh_data) {
842                 sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
843                             RDAC_NAME);
844                 return 0;
845         }
846
847         scsi_dh_data->scsi_dh = &rdac_dh;
848         h = (struct rdac_dh_data *) scsi_dh_data->buf;
849         h->lun = UNINITIALIZED_LUN;
850         h->state = RDAC_STATE_ACTIVE;
851
852         err = get_lun_info(sdev, h, array_name);
853         if (err != SCSI_DH_OK)
854                 goto failed;
855
856         err = initialize_controller(sdev, h, array_name);
857         if (err != SCSI_DH_OK)
858                 goto failed;
859
860         err = check_ownership(sdev, h);
861         if (err != SCSI_DH_OK)
862                 goto clean_ctlr;
863
864         err = set_mode_select(sdev, h);
865         if (err != SCSI_DH_OK)
866                 goto clean_ctlr;
867
868         if (!try_module_get(THIS_MODULE))
869                 goto clean_ctlr;
870
871         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
872         sdev->scsi_dh_data = scsi_dh_data;
873         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
874
875         sdev_printk(KERN_NOTICE, sdev,
876                     "%s: LUN %d (%s) (%s)\n",
877                     RDAC_NAME, h->lun, mode[(int)h->mode],
878                     lun_state[(int)h->lun_state]);
879
880         return 0;
881
882 clean_ctlr:
883         kref_put(&h->ctlr->kref, release_controller);
884
885 failed:
886         kfree(scsi_dh_data);
887         sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
888                     RDAC_NAME);
889         return -EINVAL;
890 }
891
892 static void rdac_bus_detach( struct scsi_device *sdev )
893 {
894         struct scsi_dh_data *scsi_dh_data;
895         struct rdac_dh_data *h;
896         unsigned long flags;
897
898         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
899         scsi_dh_data = sdev->scsi_dh_data;
900         sdev->scsi_dh_data = NULL;
901         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
902
903         h = (struct rdac_dh_data *) scsi_dh_data->buf;
904         if (h->ctlr)
905                 kref_put(&h->ctlr->kref, release_controller);
906         kfree(scsi_dh_data);
907         module_put(THIS_MODULE);
908         sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", RDAC_NAME);
909 }
910
911
912
913 static int __init rdac_init(void)
914 {
915         int r;
916
917         r = scsi_register_device_handler(&rdac_dh);
918         if (r != 0) {
919                 printk(KERN_ERR "Failed to register scsi device handler.");
920                 goto done;
921         }
922
923         /*
924          * Create workqueue to handle mode selects for rdac
925          */
926         kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd");
927         if (!kmpath_rdacd) {
928                 scsi_unregister_device_handler(&rdac_dh);
929                 printk(KERN_ERR "kmpath_rdacd creation failed.\n");
930         }
931 done:
932         return r;
933 }
934
935 static void __exit rdac_exit(void)
936 {
937         destroy_workqueue(kmpath_rdacd);
938         scsi_unregister_device_handler(&rdac_dh);
939 }
940
941 module_init(rdac_init);
942 module_exit(rdac_exit);
943
944 MODULE_DESCRIPTION("Multipath LSI/Engenio RDAC driver");
945 MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
946 MODULE_VERSION("01.00.0000.0000");
947 MODULE_LICENSE("GPL");