[GFS2] Fix up merge of Linus' kernel into GFS2
[pandora-kernel.git] / drivers / scsi / libsas / sas_scsi_host.c
1 /*
2  * Serial Attached SCSI (SAS) class SCSI Host glue.
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of the
12  * License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
22  * USA
23  *
24  */
25
26 #include "sas_internal.h"
27
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_tcq.h>
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_transport.h>
33 #include <scsi/scsi_transport_sas.h>
34 #include "../scsi_sas_internal.h"
35
36 #include <linux/err.h>
37 #include <linux/blkdev.h>
38 #include <linux/scatterlist.h>
39
40 /* ---------- SCSI Host glue ---------- */
41
42 #define TO_SAS_TASK(_scsi_cmd)  ((void *)(_scsi_cmd)->host_scribble)
43 #define ASSIGN_SAS_TASK(_sc, _t) do { (_sc)->host_scribble = (void *) _t; } while (0)
44
45 static void sas_scsi_task_done(struct sas_task *task)
46 {
47         struct task_status_struct *ts = &task->task_status;
48         struct scsi_cmnd *sc = task->uldd_task;
49         unsigned ts_flags = task->task_state_flags;
50         int hs = 0, stat = 0;
51
52         if (unlikely(!sc)) {
53                 SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
54                 list_del_init(&task->list);
55                 sas_free_task(task);
56                 return;
57         }
58
59         if (ts->resp == SAS_TASK_UNDELIVERED) {
60                 /* transport error */
61                 hs = DID_NO_CONNECT;
62         } else { /* ts->resp == SAS_TASK_COMPLETE */
63                 /* task delivered, what happened afterwards? */
64                 switch (ts->stat) {
65                 case SAS_DEV_NO_RESPONSE:
66                 case SAS_INTERRUPTED:
67                 case SAS_PHY_DOWN:
68                 case SAS_NAK_R_ERR:
69                 case SAS_OPEN_TO:
70                         hs = DID_NO_CONNECT;
71                         break;
72                 case SAS_DATA_UNDERRUN:
73                         sc->resid = ts->residual;
74                         if (sc->request_bufflen - sc->resid < sc->underflow)
75                                 hs = DID_ERROR;
76                         break;
77                 case SAS_DATA_OVERRUN:
78                         hs = DID_ERROR;
79                         break;
80                 case SAS_QUEUE_FULL:
81                         hs = DID_SOFT_ERROR; /* retry */
82                         break;
83                 case SAS_DEVICE_UNKNOWN:
84                         hs = DID_BAD_TARGET;
85                         break;
86                 case SAS_SG_ERR:
87                         hs = DID_PARITY;
88                         break;
89                 case SAS_OPEN_REJECT:
90                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
91                                 hs = DID_SOFT_ERROR; /* retry */
92                         else
93                                 hs = DID_ERROR;
94                         break;
95                 case SAS_PROTO_RESPONSE:
96                         SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
97                                     "task; please report this\n",
98                                     task->dev->port->ha->sas_ha_name);
99                         break;
100                 case SAS_ABORTED_TASK:
101                         hs = DID_ABORT;
102                         break;
103                 case SAM_CHECK_COND:
104                         memcpy(sc->sense_buffer, ts->buf,
105                                max(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
106                         stat = SAM_CHECK_COND;
107                         break;
108                 default:
109                         stat = ts->stat;
110                         break;
111                 }
112         }
113         ASSIGN_SAS_TASK(sc, NULL);
114         sc->result = (hs << 16) | stat;
115         list_del_init(&task->list);
116         sas_free_task(task);
117         /* This is very ugly but this is how SCSI Core works. */
118         if (ts_flags & SAS_TASK_STATE_ABORTED)
119                 scsi_finish_command(sc);
120         else
121                 sc->scsi_done(sc);
122 }
123
124 static enum task_attribute sas_scsi_get_task_attr(struct scsi_cmnd *cmd)
125 {
126         enum task_attribute ta = TASK_ATTR_SIMPLE;
127         if (cmd->request && blk_rq_tagged(cmd->request)) {
128                 if (cmd->device->ordered_tags &&
129                     (cmd->request->flags & REQ_HARDBARRIER))
130                         ta = TASK_ATTR_HOQ;
131         }
132         return ta;
133 }
134
135 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
136                                                struct domain_device *dev,
137                                                gfp_t gfp_flags)
138 {
139         struct sas_task *task = sas_alloc_task(gfp_flags);
140         struct scsi_lun lun;
141
142         if (!task)
143                 return NULL;
144
145         *(u32 *)cmd->sense_buffer = 0;
146         task->uldd_task = cmd;
147         ASSIGN_SAS_TASK(cmd, task);
148
149         task->dev = dev;
150         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
151
152         task->ssp_task.retry_count = 1;
153         int_to_scsilun(cmd->device->lun, &lun);
154         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
155         task->ssp_task.task_attr = sas_scsi_get_task_attr(cmd);
156         memcpy(task->ssp_task.cdb, cmd->cmnd, 16);
157
158         task->scatter = cmd->request_buffer;
159         task->num_scatter = cmd->use_sg;
160         task->total_xfer_len = cmd->request_bufflen;
161         task->data_dir = cmd->sc_data_direction;
162
163         task->task_done = sas_scsi_task_done;
164
165         return task;
166 }
167
168 static int sas_queue_up(struct sas_task *task)
169 {
170         struct sas_ha_struct *sas_ha = task->dev->port->ha;
171         struct scsi_core *core = &sas_ha->core;
172         unsigned long flags;
173         LIST_HEAD(list);
174
175         spin_lock_irqsave(&core->task_queue_lock, flags);
176         if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
177                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
178                 return -SAS_QUEUE_FULL;
179         }
180         list_add_tail(&task->list, &core->task_queue);
181         core->task_queue_size += 1;
182         spin_unlock_irqrestore(&core->task_queue_lock, flags);
183         up(&core->queue_thread_sema);
184
185         return 0;
186 }
187
188 /**
189  * sas_queuecommand -- Enqueue a command for processing
190  * @parameters: See SCSI Core documentation
191  *
192  * Note: XXX: Remove the host unlock/lock pair when SCSI Core can
193  * call us without holding an IRQ spinlock...
194  */
195 int sas_queuecommand(struct scsi_cmnd *cmd,
196                      void (*scsi_done)(struct scsi_cmnd *))
197 {
198         int res = 0;
199         struct domain_device *dev = cmd_to_domain_dev(cmd);
200         struct Scsi_Host *host = cmd->device->host;
201         struct sas_internal *i = to_sas_internal(host->transportt);
202
203         spin_unlock_irq(host->host_lock);
204
205         {
206                 struct sas_ha_struct *sas_ha = dev->port->ha;
207                 struct sas_task *task;
208
209                 res = -ENOMEM;
210                 task = sas_create_task(cmd, dev, GFP_ATOMIC);
211                 if (!task)
212                         goto out;
213
214                 cmd->scsi_done = scsi_done;
215                 /* Queue up, Direct Mode or Task Collector Mode. */
216                 if (sas_ha->lldd_max_execute_num < 2)
217                         res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
218                 else
219                         res = sas_queue_up(task);
220
221                 /* Examine */
222                 if (res) {
223                         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
224                         ASSIGN_SAS_TASK(cmd, NULL);
225                         sas_free_task(task);
226                         if (res == -SAS_QUEUE_FULL) {
227                                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
228                                 res = 0;
229                                 scsi_done(cmd);
230                         }
231                         goto out;
232                 }
233         }
234 out:
235         spin_lock_irq(host->host_lock);
236         return res;
237 }
238
239 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
240 {
241         struct scsi_cmnd *cmd, *n;
242
243         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
244                 if (cmd == my_cmd)
245                         list_del_init(&cmd->eh_entry);
246         }
247 }
248
249 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
250                                      struct domain_device *dev)
251 {
252         struct scsi_cmnd *cmd, *n;
253
254         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
255                 struct domain_device *x = cmd_to_domain_dev(cmd);
256
257                 if (x == dev)
258                         list_del_init(&cmd->eh_entry);
259         }
260 }
261
262 static void sas_scsi_clear_queue_port(struct list_head *error_q,
263                                       struct asd_sas_port *port)
264 {
265         struct scsi_cmnd *cmd, *n;
266
267         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
268                 struct domain_device *dev = cmd_to_domain_dev(cmd);
269                 struct asd_sas_port *x = dev->port;
270
271                 if (x == port)
272                         list_del_init(&cmd->eh_entry);
273         }
274 }
275
276 enum task_disposition {
277         TASK_IS_DONE,
278         TASK_IS_ABORTED,
279         TASK_IS_AT_LU,
280         TASK_IS_NOT_AT_LU,
281 };
282
283 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
284 {
285         struct sas_ha_struct *ha = task->dev->port->ha;
286         unsigned long flags;
287         int i, res;
288         struct sas_internal *si =
289                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
290
291         if (ha->lldd_max_execute_num > 1) {
292                 struct scsi_core *core = &ha->core;
293                 struct sas_task *t, *n;
294
295                 spin_lock_irqsave(&core->task_queue_lock, flags);
296                 list_for_each_entry_safe(t, n, &core->task_queue, list) {
297                         if (task == t) {
298                                 list_del_init(&t->list);
299                                 spin_unlock_irqrestore(&core->task_queue_lock,
300                                                        flags);
301                                 SAS_DPRINTK("%s: task 0x%p aborted from "
302                                             "task_queue\n",
303                                             __FUNCTION__, task);
304                                 return TASK_IS_ABORTED;
305                         }
306                 }
307                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
308         }
309
310         for (i = 0; i < 5; i++) {
311                 SAS_DPRINTK("%s: aborting task 0x%p\n", __FUNCTION__, task);
312                 res = si->dft->lldd_abort_task(task);
313
314                 spin_lock_irqsave(&task->task_state_lock, flags);
315                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
316                         spin_unlock_irqrestore(&task->task_state_lock, flags);
317                         SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
318                                     task);
319                         return TASK_IS_DONE;
320                 }
321                 spin_unlock_irqrestore(&task->task_state_lock, flags);
322
323                 if (res == TMF_RESP_FUNC_COMPLETE) {
324                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
325                                     __FUNCTION__, task);
326                         return TASK_IS_ABORTED;
327                 } else if (si->dft->lldd_query_task) {
328                         SAS_DPRINTK("%s: querying task 0x%p\n",
329                                     __FUNCTION__, task);
330                         res = si->dft->lldd_query_task(task);
331                         if (res == TMF_RESP_FUNC_SUCC) {
332                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
333                                             __FUNCTION__, task);
334                                 return TASK_IS_AT_LU;
335                         } else if (res == TMF_RESP_FUNC_COMPLETE) {
336                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
337                                             __FUNCTION__, task);
338                                 return TASK_IS_NOT_AT_LU;
339                         }
340                 }
341         }
342         return res;
343 }
344
345 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
346 {
347         int res = TMF_RESP_FUNC_FAILED;
348         struct scsi_lun lun;
349         struct sas_internal *i =
350                 to_sas_internal(dev->port->ha->core.shost->transportt);
351
352         int_to_scsilun(cmd->device->lun, &lun);
353
354         SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
355                     SAS_ADDR(dev->sas_addr),
356                     cmd->device->lun);
357
358         if (i->dft->lldd_abort_task_set)
359                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
360
361         if (res == TMF_RESP_FUNC_FAILED) {
362                 if (i->dft->lldd_clear_task_set)
363                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
364         }
365
366         if (res == TMF_RESP_FUNC_FAILED) {
367                 if (i->dft->lldd_lu_reset)
368                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
369         }
370
371         return res;
372 }
373
374 static int sas_recover_I_T(struct domain_device *dev)
375 {
376         int res = TMF_RESP_FUNC_FAILED;
377         struct sas_internal *i =
378                 to_sas_internal(dev->port->ha->core.shost->transportt);
379
380         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
381                     SAS_ADDR(dev->sas_addr));
382
383         if (i->dft->lldd_I_T_nexus_reset)
384                 res = i->dft->lldd_I_T_nexus_reset(dev);
385
386         return res;
387 }
388
389 void sas_scsi_recover_host(struct Scsi_Host *shost)
390 {
391         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
392         unsigned long flags;
393         LIST_HEAD(error_q);
394         struct scsi_cmnd *cmd, *n;
395         enum task_disposition res = TASK_IS_DONE;
396         int tmf_resp;
397         struct sas_internal *i = to_sas_internal(shost->transportt);
398
399         spin_lock_irqsave(shost->host_lock, flags);
400         list_splice_init(&shost->eh_cmd_q, &error_q);
401         spin_unlock_irqrestore(shost->host_lock, flags);
402
403         SAS_DPRINTK("Enter %s\n", __FUNCTION__);
404
405         /* All tasks on this list were marked SAS_TASK_STATE_ABORTED
406          * by sas_scsi_timed_out() callback.
407          */
408 Again:
409         SAS_DPRINTK("going over list...\n");
410         list_for_each_entry_safe(cmd, n, &error_q, eh_entry) {
411                 struct sas_task *task = TO_SAS_TASK(cmd);
412
413                 SAS_DPRINTK("trying to find task 0x%p\n", task);
414                 list_del_init(&cmd->eh_entry);
415                 res = sas_scsi_find_task(task);
416
417                 cmd->eh_eflags = 0;
418                 shost->host_failed--;
419
420                 switch (res) {
421                 case TASK_IS_DONE:
422                         SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
423                                     task);
424                         task->task_done(task);
425                         continue;
426                 case TASK_IS_ABORTED:
427                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
428                                     __FUNCTION__, task);
429                         task->task_done(task);
430                         continue;
431                 case TASK_IS_AT_LU:
432                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
433                         tmf_resp = sas_recover_lu(task->dev, cmd);
434                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
435                                 SAS_DPRINTK("dev %016llx LU %x is "
436                                             "recovered\n",
437                                             SAS_ADDR(task->dev),
438                                             cmd->device->lun);
439                                 task->task_done(task);
440                                 sas_scsi_clear_queue_lu(&error_q, cmd);
441                                 goto Again;
442                         }
443                         /* fallthrough */
444                 case TASK_IS_NOT_AT_LU:
445                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
446                                     task);
447                         tmf_resp = sas_recover_I_T(task->dev);
448                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
449                                 SAS_DPRINTK("I_T %016llx recovered\n",
450                                             SAS_ADDR(task->dev->sas_addr));
451                                 task->task_done(task);
452                                 sas_scsi_clear_queue_I_T(&error_q, task->dev);
453                                 goto Again;
454                         }
455                         /* Hammer time :-) */
456                         if (i->dft->lldd_clear_nexus_port) {
457                                 struct asd_sas_port *port = task->dev->port;
458                                 SAS_DPRINTK("clearing nexus for port:%d\n",
459                                             port->id);
460                                 res = i->dft->lldd_clear_nexus_port(port);
461                                 if (res == TMF_RESP_FUNC_COMPLETE) {
462                                         SAS_DPRINTK("clear nexus port:%d "
463                                                     "succeeded\n", port->id);
464                                         task->task_done(task);
465                                         sas_scsi_clear_queue_port(&error_q,
466                                                                   port);
467                                         goto Again;
468                                 }
469                         }
470                         if (i->dft->lldd_clear_nexus_ha) {
471                                 SAS_DPRINTK("clear nexus ha\n");
472                                 res = i->dft->lldd_clear_nexus_ha(ha);
473                                 if (res == TMF_RESP_FUNC_COMPLETE) {
474                                         SAS_DPRINTK("clear nexus ha "
475                                                     "succeeded\n");
476                                         task->task_done(task);
477                                         goto out;
478                                 }
479                         }
480                         /* If we are here -- this means that no amount
481                          * of effort could recover from errors.  Quite
482                          * possibly the HA just disappeared.
483                          */
484                         SAS_DPRINTK("error from  device %llx, LUN %x "
485                                     "couldn't be recovered in any way\n",
486                                     SAS_ADDR(task->dev->sas_addr),
487                                     cmd->device->lun);
488
489                         task->task_done(task);
490                         goto clear_q;
491                 }
492         }
493 out:
494         SAS_DPRINTK("--- Exit %s\n", __FUNCTION__);
495         return;
496 clear_q:
497         SAS_DPRINTK("--- Exit %s -- clear_q\n", __FUNCTION__);
498         list_for_each_entry_safe(cmd, n, &error_q, eh_entry) {
499                 struct sas_task *task = TO_SAS_TASK(cmd);
500                 list_del_init(&cmd->eh_entry);
501                 task->task_done(task);
502         }
503 }
504
505 enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
506 {
507         struct sas_task *task = TO_SAS_TASK(cmd);
508         unsigned long flags;
509
510         if (!task) {
511                 SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
512                             cmd, task);
513                 return EH_HANDLED;
514         }
515
516         spin_lock_irqsave(&task->task_state_lock, flags);
517         if (task->task_state_flags & SAS_TASK_STATE_DONE) {
518                 spin_unlock_irqrestore(&task->task_state_lock, flags);
519                 SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
520                             cmd, task);
521                 return EH_HANDLED;
522         }
523         task->task_state_flags |= SAS_TASK_STATE_ABORTED;
524         spin_unlock_irqrestore(&task->task_state_lock, flags);
525
526         SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_NOT_HANDLED\n",
527                     cmd, task);
528
529         return EH_NOT_HANDLED;
530 }
531
532 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
533 {
534         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
535         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
536         struct domain_device *found_dev = NULL;
537         int i;
538
539         spin_lock(&ha->phy_port_lock);
540         for (i = 0; i < ha->num_phys; i++) {
541                 struct asd_sas_port *port = ha->sas_port[i];
542                 struct domain_device *dev;
543
544                 spin_lock(&port->dev_list_lock);
545                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
546                         if (rphy == dev->rphy) {
547                                 found_dev = dev;
548                                 spin_unlock(&port->dev_list_lock);
549                                 goto found;
550                         }
551                 }
552                 spin_unlock(&port->dev_list_lock);
553         }
554  found:
555         spin_unlock(&ha->phy_port_lock);
556
557         return found_dev;
558 }
559
560 static inline struct domain_device *sas_find_target(struct scsi_target *starget)
561 {
562         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
563
564         return sas_find_dev_by_rphy(rphy);
565 }
566
567 int sas_target_alloc(struct scsi_target *starget)
568 {
569         struct domain_device *found_dev = sas_find_target(starget);
570
571         if (!found_dev)
572                 return -ENODEV;
573
574         starget->hostdata = found_dev;
575         return 0;
576 }
577
578 #define SAS_DEF_QD 32
579 #define SAS_MAX_QD 64
580
581 int sas_slave_configure(struct scsi_device *scsi_dev)
582 {
583         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
584         struct sas_ha_struct *sas_ha;
585
586         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
587
588         sas_ha = dev->port->ha;
589
590         sas_read_port_mode_page(scsi_dev);
591
592         if (scsi_dev->tagged_supported) {
593                 scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
594                 scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
595         } else {
596                 SAS_DPRINTK("device %llx, LUN %x doesn't support "
597                             "TCQ\n", SAS_ADDR(dev->sas_addr),
598                             scsi_dev->lun);
599                 scsi_dev->tagged_supported = 0;
600                 scsi_set_tag_type(scsi_dev, 0);
601                 scsi_deactivate_tcq(scsi_dev, 1);
602         }
603
604         return 0;
605 }
606
607 void sas_slave_destroy(struct scsi_device *scsi_dev)
608 {
609 }
610
611 int sas_change_queue_depth(struct scsi_device *scsi_dev, int new_depth)
612 {
613         int res = min(new_depth, SAS_MAX_QD);
614
615         if (scsi_dev->tagged_supported)
616                 scsi_adjust_queue_depth(scsi_dev, scsi_get_tag_type(scsi_dev),
617                                         res);
618         else {
619                 struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
620                 sas_printk("device %llx LUN %x queue depth changed to 1\n",
621                            SAS_ADDR(dev->sas_addr),
622                            scsi_dev->lun);
623                 scsi_adjust_queue_depth(scsi_dev, 0, 1);
624                 res = 1;
625         }
626
627         return res;
628 }
629
630 int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
631 {
632         if (!scsi_dev->tagged_supported)
633                 return 0;
634
635         scsi_deactivate_tcq(scsi_dev, 1);
636
637         scsi_set_tag_type(scsi_dev, qt);
638         scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
639
640         return qt;
641 }
642
643 int sas_bios_param(struct scsi_device *scsi_dev,
644                           struct block_device *bdev,
645                           sector_t capacity, int *hsc)
646 {
647         hsc[0] = 255;
648         hsc[1] = 63;
649         sector_div(capacity, 255*63);
650         hsc[2] = capacity;
651
652         return 0;
653 }
654
655 /* ---------- Task Collector Thread implementation ---------- */
656
657 static void sas_queue(struct sas_ha_struct *sas_ha)
658 {
659         struct scsi_core *core = &sas_ha->core;
660         unsigned long flags;
661         LIST_HEAD(q);
662         int can_queue;
663         int res;
664         struct sas_internal *i = to_sas_internal(core->shost->transportt);
665
666         spin_lock_irqsave(&core->task_queue_lock, flags);
667         while (!core->queue_thread_kill &&
668                !list_empty(&core->task_queue)) {
669
670                 can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
671                 if (can_queue >= 0) {
672                         can_queue = core->task_queue_size;
673                         list_splice_init(&core->task_queue, &q);
674                 } else {
675                         struct list_head *a, *n;
676
677                         can_queue = sas_ha->lldd_queue_size;
678                         list_for_each_safe(a, n, &core->task_queue) {
679                                 list_move_tail(a, &q);
680                                 if (--can_queue == 0)
681                                         break;
682                         }
683                         can_queue = sas_ha->lldd_queue_size;
684                 }
685                 core->task_queue_size -= can_queue;
686                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
687                 {
688                         struct sas_task *task = list_entry(q.next,
689                                                            struct sas_task,
690                                                            list);
691                         list_del_init(&q);
692                         res = i->dft->lldd_execute_task(task, can_queue,
693                                                         GFP_KERNEL);
694                         if (unlikely(res))
695                                 __list_add(&q, task->list.prev, &task->list);
696                 }
697                 spin_lock_irqsave(&core->task_queue_lock, flags);
698                 if (res) {
699                         list_splice_init(&q, &core->task_queue); /*at head*/
700                         core->task_queue_size += can_queue;
701                 }
702         }
703         spin_unlock_irqrestore(&core->task_queue_lock, flags);
704 }
705
706 static DECLARE_COMPLETION(queue_th_comp);
707
708 /**
709  * sas_queue_thread -- The Task Collector thread
710  * @_sas_ha: pointer to struct sas_ha
711  */
712 static int sas_queue_thread(void *_sas_ha)
713 {
714         struct sas_ha_struct *sas_ha = _sas_ha;
715         struct scsi_core *core = &sas_ha->core;
716
717         daemonize("sas_queue_%d", core->shost->host_no);
718         current->flags |= PF_NOFREEZE;
719
720         complete(&queue_th_comp);
721
722         while (1) {
723                 down_interruptible(&core->queue_thread_sema);
724                 sas_queue(sas_ha);
725                 if (core->queue_thread_kill)
726                         break;
727         }
728
729         complete(&queue_th_comp);
730
731         return 0;
732 }
733
734 int sas_init_queue(struct sas_ha_struct *sas_ha)
735 {
736         int res;
737         struct scsi_core *core = &sas_ha->core;
738
739         spin_lock_init(&core->task_queue_lock);
740         core->task_queue_size = 0;
741         INIT_LIST_HEAD(&core->task_queue);
742         init_MUTEX_LOCKED(&core->queue_thread_sema);
743
744         res = kernel_thread(sas_queue_thread, sas_ha, 0);
745         if (res >= 0)
746                 wait_for_completion(&queue_th_comp);
747
748         return res < 0 ? res : 0;
749 }
750
751 void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
752 {
753         unsigned long flags;
754         struct scsi_core *core = &sas_ha->core;
755         struct sas_task *task, *n;
756
757         init_completion(&queue_th_comp);
758         core->queue_thread_kill = 1;
759         up(&core->queue_thread_sema);
760         wait_for_completion(&queue_th_comp);
761
762         if (!list_empty(&core->task_queue))
763                 SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
764                             SAS_ADDR(sas_ha->sas_addr));
765
766         spin_lock_irqsave(&core->task_queue_lock, flags);
767         list_for_each_entry_safe(task, n, &core->task_queue, list) {
768                 struct scsi_cmnd *cmd = task->uldd_task;
769
770                 list_del_init(&task->list);
771
772                 ASSIGN_SAS_TASK(cmd, NULL);
773                 sas_free_task(task);
774                 cmd->result = DID_ABORT << 16;
775                 cmd->scsi_done(cmd);
776         }
777         spin_unlock_irqrestore(&core->task_queue_lock, flags);
778 }
779
780 EXPORT_SYMBOL_GPL(sas_queuecommand);
781 EXPORT_SYMBOL_GPL(sas_target_alloc);
782 EXPORT_SYMBOL_GPL(sas_slave_configure);
783 EXPORT_SYMBOL_GPL(sas_slave_destroy);
784 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
785 EXPORT_SYMBOL_GPL(sas_change_queue_type);
786 EXPORT_SYMBOL_GPL(sas_bios_param);