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Merge branch 'for-3.11/drivers' of git://git.kernel.dk/linux-block
[~andy/linux] / 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 <linux/kthread.h>
27 #include <linux/firmware.h>
28 #include <linux/export.h>
29 #include <linux/ctype.h>
30
31 #include "sas_internal.h"
32
33 #include <scsi/scsi_host.h>
34 #include <scsi/scsi_device.h>
35 #include <scsi/scsi_tcq.h>
36 #include <scsi/scsi.h>
37 #include <scsi/scsi_eh.h>
38 #include <scsi/scsi_transport.h>
39 #include <scsi/scsi_transport_sas.h>
40 #include <scsi/sas_ata.h>
41 #include "../scsi_sas_internal.h"
42 #include "../scsi_transport_api.h"
43 #include "../scsi_priv.h"
44
45 #include <linux/err.h>
46 #include <linux/blkdev.h>
47 #include <linux/freezer.h>
48 #include <linux/gfp.h>
49 #include <linux/scatterlist.h>
50 #include <linux/libata.h>
51
52 /* record final status and free the task */
53 static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
54 {
55         struct task_status_struct *ts = &task->task_status;
56         int hs = 0, stat = 0;
57
58         if (ts->resp == SAS_TASK_UNDELIVERED) {
59                 /* transport error */
60                 hs = DID_NO_CONNECT;
61         } else { /* ts->resp == SAS_TASK_COMPLETE */
62                 /* task delivered, what happened afterwards? */
63                 switch (ts->stat) {
64                 case SAS_DEV_NO_RESPONSE:
65                 case SAS_INTERRUPTED:
66                 case SAS_PHY_DOWN:
67                 case SAS_NAK_R_ERR:
68                 case SAS_OPEN_TO:
69                         hs = DID_NO_CONNECT;
70                         break;
71                 case SAS_DATA_UNDERRUN:
72                         scsi_set_resid(sc, ts->residual);
73                         if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
74                                 hs = DID_ERROR;
75                         break;
76                 case SAS_DATA_OVERRUN:
77                         hs = DID_ERROR;
78                         break;
79                 case SAS_QUEUE_FULL:
80                         hs = DID_SOFT_ERROR; /* retry */
81                         break;
82                 case SAS_DEVICE_UNKNOWN:
83                         hs = DID_BAD_TARGET;
84                         break;
85                 case SAS_SG_ERR:
86                         hs = DID_PARITY;
87                         break;
88                 case SAS_OPEN_REJECT:
89                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
90                                 hs = DID_SOFT_ERROR; /* retry */
91                         else
92                                 hs = DID_ERROR;
93                         break;
94                 case SAS_PROTO_RESPONSE:
95                         SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
96                                     "task; please report this\n",
97                                     task->dev->port->ha->sas_ha_name);
98                         break;
99                 case SAS_ABORTED_TASK:
100                         hs = DID_ABORT;
101                         break;
102                 case SAM_STAT_CHECK_CONDITION:
103                         memcpy(sc->sense_buffer, ts->buf,
104                                min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
105                         stat = SAM_STAT_CHECK_CONDITION;
106                         break;
107                 default:
108                         stat = ts->stat;
109                         break;
110                 }
111         }
112
113         sc->result = (hs << 16) | stat;
114         ASSIGN_SAS_TASK(sc, NULL);
115         list_del_init(&task->list);
116         sas_free_task(task);
117 }
118
119 static void sas_scsi_task_done(struct sas_task *task)
120 {
121         struct scsi_cmnd *sc = task->uldd_task;
122         struct domain_device *dev = task->dev;
123         struct sas_ha_struct *ha = dev->port->ha;
124         unsigned long flags;
125
126         spin_lock_irqsave(&dev->done_lock, flags);
127         if (test_bit(SAS_HA_FROZEN, &ha->state))
128                 task = NULL;
129         else
130                 ASSIGN_SAS_TASK(sc, NULL);
131         spin_unlock_irqrestore(&dev->done_lock, flags);
132
133         if (unlikely(!task)) {
134                 /* task will be completed by the error handler */
135                 SAS_DPRINTK("task done but aborted\n");
136                 return;
137         }
138
139         if (unlikely(!sc)) {
140                 SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
141                 list_del_init(&task->list);
142                 sas_free_task(task);
143                 return;
144         }
145
146         sas_end_task(sc, task);
147         sc->scsi_done(sc);
148 }
149
150 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
151                                                struct domain_device *dev,
152                                                gfp_t gfp_flags)
153 {
154         struct sas_task *task = sas_alloc_task(gfp_flags);
155         struct scsi_lun lun;
156
157         if (!task)
158                 return NULL;
159
160         task->uldd_task = cmd;
161         ASSIGN_SAS_TASK(cmd, task);
162
163         task->dev = dev;
164         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
165
166         task->ssp_task.retry_count = 1;
167         int_to_scsilun(cmd->device->lun, &lun);
168         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
169         task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
170         task->ssp_task.cmd = cmd;
171
172         task->scatter = scsi_sglist(cmd);
173         task->num_scatter = scsi_sg_count(cmd);
174         task->total_xfer_len = scsi_bufflen(cmd);
175         task->data_dir = cmd->sc_data_direction;
176
177         task->task_done = sas_scsi_task_done;
178
179         return task;
180 }
181
182 int sas_queue_up(struct sas_task *task)
183 {
184         struct sas_ha_struct *sas_ha = task->dev->port->ha;
185         struct scsi_core *core = &sas_ha->core;
186         unsigned long flags;
187         LIST_HEAD(list);
188
189         spin_lock_irqsave(&core->task_queue_lock, flags);
190         if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
191                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
192                 return -SAS_QUEUE_FULL;
193         }
194         list_add_tail(&task->list, &core->task_queue);
195         core->task_queue_size += 1;
196         spin_unlock_irqrestore(&core->task_queue_lock, flags);
197         wake_up_process(core->queue_thread);
198
199         return 0;
200 }
201
202 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
203 {
204         struct sas_internal *i = to_sas_internal(host->transportt);
205         struct domain_device *dev = cmd_to_domain_dev(cmd);
206         struct sas_ha_struct *sas_ha = dev->port->ha;
207         struct sas_task *task;
208         int res = 0;
209
210         /* If the device fell off, no sense in issuing commands */
211         if (test_bit(SAS_DEV_GONE, &dev->state)) {
212                 cmd->result = DID_BAD_TARGET << 16;
213                 goto out_done;
214         }
215
216         if (dev_is_sata(dev)) {
217                 spin_lock_irq(dev->sata_dev.ap->lock);
218                 res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
219                 spin_unlock_irq(dev->sata_dev.ap->lock);
220                 return res;
221         }
222
223         task = sas_create_task(cmd, dev, GFP_ATOMIC);
224         if (!task)
225                 return SCSI_MLQUEUE_HOST_BUSY;
226
227         /* Queue up, Direct Mode or Task Collector Mode. */
228         if (sas_ha->lldd_max_execute_num < 2)
229                 res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
230         else
231                 res = sas_queue_up(task);
232
233         if (res)
234                 goto out_free_task;
235         return 0;
236
237 out_free_task:
238         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
239         ASSIGN_SAS_TASK(cmd, NULL);
240         sas_free_task(task);
241         if (res == -SAS_QUEUE_FULL)
242                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
243         else
244                 cmd->result = DID_ERROR << 16;
245 out_done:
246         cmd->scsi_done(cmd);
247         return 0;
248 }
249
250 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
251 {
252         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
253         struct sas_task *task = TO_SAS_TASK(cmd);
254
255         /* At this point, we only get called following an actual abort
256          * of the task, so we should be guaranteed not to be racing with
257          * any completions from the LLD.  Task is freed after this.
258          */
259         sas_end_task(cmd, task);
260
261         /* now finish the command and move it on to the error
262          * handler done list, this also takes it off the
263          * error handler pending list.
264          */
265         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
266 }
267
268 static void sas_eh_defer_cmd(struct scsi_cmnd *cmd)
269 {
270         struct domain_device *dev = cmd_to_domain_dev(cmd);
271         struct sas_ha_struct *ha = dev->port->ha;
272         struct sas_task *task = TO_SAS_TASK(cmd);
273
274         if (!dev_is_sata(dev)) {
275                 sas_eh_finish_cmd(cmd);
276                 return;
277         }
278
279         /* report the timeout to libata */
280         sas_end_task(cmd, task);
281         list_move_tail(&cmd->eh_entry, &ha->eh_ata_q);
282 }
283
284 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
285 {
286         struct scsi_cmnd *cmd, *n;
287
288         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
289                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
290                     cmd->device->lun == my_cmd->device->lun)
291                         sas_eh_defer_cmd(cmd);
292         }
293 }
294
295 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
296                                      struct domain_device *dev)
297 {
298         struct scsi_cmnd *cmd, *n;
299
300         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
301                 struct domain_device *x = cmd_to_domain_dev(cmd);
302
303                 if (x == dev)
304                         sas_eh_finish_cmd(cmd);
305         }
306 }
307
308 static void sas_scsi_clear_queue_port(struct list_head *error_q,
309                                       struct asd_sas_port *port)
310 {
311         struct scsi_cmnd *cmd, *n;
312
313         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
314                 struct domain_device *dev = cmd_to_domain_dev(cmd);
315                 struct asd_sas_port *x = dev->port;
316
317                 if (x == port)
318                         sas_eh_finish_cmd(cmd);
319         }
320 }
321
322 enum task_disposition {
323         TASK_IS_DONE,
324         TASK_IS_ABORTED,
325         TASK_IS_AT_LU,
326         TASK_IS_NOT_AT_HA,
327         TASK_IS_NOT_AT_LU,
328         TASK_ABORT_FAILED,
329 };
330
331 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
332 {
333         struct sas_ha_struct *ha = task->dev->port->ha;
334         unsigned long flags;
335         int i, res;
336         struct sas_internal *si =
337                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
338
339         if (ha->lldd_max_execute_num > 1) {
340                 struct scsi_core *core = &ha->core;
341                 struct sas_task *t, *n;
342
343                 mutex_lock(&core->task_queue_flush);
344                 spin_lock_irqsave(&core->task_queue_lock, flags);
345                 list_for_each_entry_safe(t, n, &core->task_queue, list)
346                         if (task == t) {
347                                 list_del_init(&t->list);
348                                 break;
349                         }
350                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
351                 mutex_unlock(&core->task_queue_flush);
352
353                 if (task == t)
354                         return TASK_IS_NOT_AT_HA;
355         }
356
357         for (i = 0; i < 5; i++) {
358                 SAS_DPRINTK("%s: aborting task 0x%p\n", __func__, task);
359                 res = si->dft->lldd_abort_task(task);
360
361                 spin_lock_irqsave(&task->task_state_lock, flags);
362                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
363                         spin_unlock_irqrestore(&task->task_state_lock, flags);
364                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
365                                     task);
366                         return TASK_IS_DONE;
367                 }
368                 spin_unlock_irqrestore(&task->task_state_lock, flags);
369
370                 if (res == TMF_RESP_FUNC_COMPLETE) {
371                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
372                                     __func__, task);
373                         return TASK_IS_ABORTED;
374                 } else if (si->dft->lldd_query_task) {
375                         SAS_DPRINTK("%s: querying task 0x%p\n",
376                                     __func__, task);
377                         res = si->dft->lldd_query_task(task);
378                         switch (res) {
379                         case TMF_RESP_FUNC_SUCC:
380                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
381                                             __func__, task);
382                                 return TASK_IS_AT_LU;
383                         case TMF_RESP_FUNC_COMPLETE:
384                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
385                                             __func__, task);
386                                 return TASK_IS_NOT_AT_LU;
387                         case TMF_RESP_FUNC_FAILED:
388                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
389                                                 __func__, task);
390                                 return TASK_ABORT_FAILED;
391                         }
392
393                 }
394         }
395         return res;
396 }
397
398 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
399 {
400         int res = TMF_RESP_FUNC_FAILED;
401         struct scsi_lun lun;
402         struct sas_internal *i =
403                 to_sas_internal(dev->port->ha->core.shost->transportt);
404
405         int_to_scsilun(cmd->device->lun, &lun);
406
407         SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
408                     SAS_ADDR(dev->sas_addr),
409                     cmd->device->lun);
410
411         if (i->dft->lldd_abort_task_set)
412                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
413
414         if (res == TMF_RESP_FUNC_FAILED) {
415                 if (i->dft->lldd_clear_task_set)
416                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
417         }
418
419         if (res == TMF_RESP_FUNC_FAILED) {
420                 if (i->dft->lldd_lu_reset)
421                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
422         }
423
424         return res;
425 }
426
427 static int sas_recover_I_T(struct domain_device *dev)
428 {
429         int res = TMF_RESP_FUNC_FAILED;
430         struct sas_internal *i =
431                 to_sas_internal(dev->port->ha->core.shost->transportt);
432
433         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
434                     SAS_ADDR(dev->sas_addr));
435
436         if (i->dft->lldd_I_T_nexus_reset)
437                 res = i->dft->lldd_I_T_nexus_reset(dev);
438
439         return res;
440 }
441
442 /* take a reference on the last known good phy for this device */
443 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
444 {
445         struct sas_ha_struct *ha = dev->port->ha;
446         struct sas_phy *phy;
447         unsigned long flags;
448
449         /* a published domain device always has a valid phy, it may be
450          * stale, but it is never NULL
451          */
452         BUG_ON(!dev->phy);
453
454         spin_lock_irqsave(&ha->phy_port_lock, flags);
455         phy = dev->phy;
456         get_device(&phy->dev);
457         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
458
459         return phy;
460 }
461 EXPORT_SYMBOL_GPL(sas_get_local_phy);
462
463 static void sas_wait_eh(struct domain_device *dev)
464 {
465         struct sas_ha_struct *ha = dev->port->ha;
466         DEFINE_WAIT(wait);
467
468         if (dev_is_sata(dev)) {
469                 ata_port_wait_eh(dev->sata_dev.ap);
470                 return;
471         }
472  retry:
473         spin_lock_irq(&ha->lock);
474
475         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
476                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
477                 spin_unlock_irq(&ha->lock);
478                 schedule();
479                 spin_lock_irq(&ha->lock);
480         }
481         finish_wait(&ha->eh_wait_q, &wait);
482
483         spin_unlock_irq(&ha->lock);
484
485         /* make sure SCSI EH is complete */
486         if (scsi_host_in_recovery(ha->core.shost)) {
487                 msleep(10);
488                 goto retry;
489         }
490 }
491 EXPORT_SYMBOL(sas_wait_eh);
492
493 static int sas_queue_reset(struct domain_device *dev, int reset_type, int lun, int wait)
494 {
495         struct sas_ha_struct *ha = dev->port->ha;
496         int scheduled = 0, tries = 100;
497
498         /* ata: promote lun reset to bus reset */
499         if (dev_is_sata(dev)) {
500                 sas_ata_schedule_reset(dev);
501                 if (wait)
502                         sas_ata_wait_eh(dev);
503                 return SUCCESS;
504         }
505
506         while (!scheduled && tries--) {
507                 spin_lock_irq(&ha->lock);
508                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
509                     !test_bit(reset_type, &dev->state)) {
510                         scheduled = 1;
511                         ha->eh_active++;
512                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
513                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
514                         set_bit(reset_type, &dev->state);
515                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
516                         scsi_schedule_eh(ha->core.shost);
517                 }
518                 spin_unlock_irq(&ha->lock);
519
520                 if (wait)
521                         sas_wait_eh(dev);
522
523                 if (scheduled)
524                         return SUCCESS;
525         }
526
527         SAS_DPRINTK("%s reset of %s failed\n",
528                     reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
529                     dev_name(&dev->rphy->dev));
530
531         return FAILED;
532 }
533
534 int sas_eh_abort_handler(struct scsi_cmnd *cmd)
535 {
536         int res;
537         struct sas_task *task = TO_SAS_TASK(cmd);
538         struct Scsi_Host *host = cmd->device->host;
539         struct sas_internal *i = to_sas_internal(host->transportt);
540
541         if (current != host->ehandler)
542                 return FAILED;
543
544         if (!i->dft->lldd_abort_task)
545                 return FAILED;
546
547         res = i->dft->lldd_abort_task(task);
548         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
549                 return SUCCESS;
550
551         return FAILED;
552 }
553 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
554
555 /* Attempt to send a LUN reset message to a device */
556 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
557 {
558         int res;
559         struct scsi_lun lun;
560         struct Scsi_Host *host = cmd->device->host;
561         struct domain_device *dev = cmd_to_domain_dev(cmd);
562         struct sas_internal *i = to_sas_internal(host->transportt);
563
564         if (current != host->ehandler)
565                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
566
567         int_to_scsilun(cmd->device->lun, &lun);
568
569         if (!i->dft->lldd_lu_reset)
570                 return FAILED;
571
572         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
573         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
574                 return SUCCESS;
575
576         return FAILED;
577 }
578
579 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
580 {
581         int res;
582         struct Scsi_Host *host = cmd->device->host;
583         struct domain_device *dev = cmd_to_domain_dev(cmd);
584         struct sas_internal *i = to_sas_internal(host->transportt);
585
586         if (current != host->ehandler)
587                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
588
589         if (!i->dft->lldd_I_T_nexus_reset)
590                 return FAILED;
591
592         res = i->dft->lldd_I_T_nexus_reset(dev);
593         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
594             res == -ENODEV)
595                 return SUCCESS;
596
597         return FAILED;
598 }
599
600 /* Try to reset a device */
601 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
602 {
603         int res;
604         struct Scsi_Host *shost = cmd->device->host;
605
606         if (!shost->hostt->eh_device_reset_handler)
607                 goto try_bus_reset;
608
609         res = shost->hostt->eh_device_reset_handler(cmd);
610         if (res == SUCCESS)
611                 return res;
612
613 try_bus_reset:
614         if (shost->hostt->eh_bus_reset_handler)
615                 return shost->hostt->eh_bus_reset_handler(cmd);
616
617         return FAILED;
618 }
619
620 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
621 {
622         struct scsi_cmnd *cmd, *n;
623         enum task_disposition res = TASK_IS_DONE;
624         int tmf_resp, need_reset;
625         struct sas_internal *i = to_sas_internal(shost->transportt);
626         unsigned long flags;
627         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
628         LIST_HEAD(done);
629
630         /* clean out any commands that won the completion vs eh race */
631         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
632                 struct domain_device *dev = cmd_to_domain_dev(cmd);
633                 struct sas_task *task;
634
635                 spin_lock_irqsave(&dev->done_lock, flags);
636                 /* by this point the lldd has either observed
637                  * SAS_HA_FROZEN and is leaving the task alone, or has
638                  * won the race with eh and decided to complete it
639                  */
640                 task = TO_SAS_TASK(cmd);
641                 spin_unlock_irqrestore(&dev->done_lock, flags);
642
643                 if (!task)
644                         list_move_tail(&cmd->eh_entry, &done);
645         }
646
647  Again:
648         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
649                 struct sas_task *task = TO_SAS_TASK(cmd);
650
651                 list_del_init(&cmd->eh_entry);
652
653                 spin_lock_irqsave(&task->task_state_lock, flags);
654                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
655                 spin_unlock_irqrestore(&task->task_state_lock, flags);
656
657                 if (need_reset) {
658                         SAS_DPRINTK("%s: task 0x%p requests reset\n",
659                                     __func__, task);
660                         goto reset;
661                 }
662
663                 SAS_DPRINTK("trying to find task 0x%p\n", task);
664                 res = sas_scsi_find_task(task);
665
666                 cmd->eh_eflags = 0;
667
668                 switch (res) {
669                 case TASK_IS_NOT_AT_HA:
670                         SAS_DPRINTK("%s: task 0x%p is not at ha: %s\n",
671                                     __func__, task,
672                                     cmd->retries ? "retry" : "aborted");
673                         if (cmd->retries)
674                                 cmd->retries--;
675                         sas_eh_finish_cmd(cmd);
676                         continue;
677                 case TASK_IS_DONE:
678                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
679                                     task);
680                         sas_eh_defer_cmd(cmd);
681                         continue;
682                 case TASK_IS_ABORTED:
683                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
684                                     __func__, task);
685                         sas_eh_defer_cmd(cmd);
686                         continue;
687                 case TASK_IS_AT_LU:
688                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
689  reset:
690                         tmf_resp = sas_recover_lu(task->dev, cmd);
691                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
692                                 SAS_DPRINTK("dev %016llx LU %x is "
693                                             "recovered\n",
694                                             SAS_ADDR(task->dev),
695                                             cmd->device->lun);
696                                 sas_eh_defer_cmd(cmd);
697                                 sas_scsi_clear_queue_lu(work_q, cmd);
698                                 goto Again;
699                         }
700                         /* fallthrough */
701                 case TASK_IS_NOT_AT_LU:
702                 case TASK_ABORT_FAILED:
703                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
704                                     task);
705                         tmf_resp = sas_recover_I_T(task->dev);
706                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
707                             tmf_resp == -ENODEV) {
708                                 struct domain_device *dev = task->dev;
709                                 SAS_DPRINTK("I_T %016llx recovered\n",
710                                             SAS_ADDR(task->dev->sas_addr));
711                                 sas_eh_finish_cmd(cmd);
712                                 sas_scsi_clear_queue_I_T(work_q, dev);
713                                 goto Again;
714                         }
715                         /* Hammer time :-) */
716                         try_to_reset_cmd_device(cmd);
717                         if (i->dft->lldd_clear_nexus_port) {
718                                 struct asd_sas_port *port = task->dev->port;
719                                 SAS_DPRINTK("clearing nexus for port:%d\n",
720                                             port->id);
721                                 res = i->dft->lldd_clear_nexus_port(port);
722                                 if (res == TMF_RESP_FUNC_COMPLETE) {
723                                         SAS_DPRINTK("clear nexus port:%d "
724                                                     "succeeded\n", port->id);
725                                         sas_eh_finish_cmd(cmd);
726                                         sas_scsi_clear_queue_port(work_q,
727                                                                   port);
728                                         goto Again;
729                                 }
730                         }
731                         if (i->dft->lldd_clear_nexus_ha) {
732                                 SAS_DPRINTK("clear nexus ha\n");
733                                 res = i->dft->lldd_clear_nexus_ha(ha);
734                                 if (res == TMF_RESP_FUNC_COMPLETE) {
735                                         SAS_DPRINTK("clear nexus ha "
736                                                     "succeeded\n");
737                                         sas_eh_finish_cmd(cmd);
738                                         goto clear_q;
739                                 }
740                         }
741                         /* If we are here -- this means that no amount
742                          * of effort could recover from errors.  Quite
743                          * possibly the HA just disappeared.
744                          */
745                         SAS_DPRINTK("error from  device %llx, LUN %x "
746                                     "couldn't be recovered in any way\n",
747                                     SAS_ADDR(task->dev->sas_addr),
748                                     cmd->device->lun);
749
750                         sas_eh_finish_cmd(cmd);
751                         goto clear_q;
752                 }
753         }
754  out:
755         list_splice_tail(&done, work_q);
756         list_splice_tail_init(&ha->eh_ata_q, work_q);
757         return;
758
759  clear_q:
760         SAS_DPRINTK("--- Exit %s -- clear_q\n", __func__);
761         list_for_each_entry_safe(cmd, n, work_q, eh_entry)
762                 sas_eh_finish_cmd(cmd);
763         goto out;
764 }
765
766 static void sas_eh_handle_resets(struct Scsi_Host *shost)
767 {
768         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
769         struct sas_internal *i = to_sas_internal(shost->transportt);
770
771         /* handle directed resets to sas devices */
772         spin_lock_irq(&ha->lock);
773         while (!list_empty(&ha->eh_dev_q)) {
774                 struct domain_device *dev;
775                 struct ssp_device *ssp;
776
777                 ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
778                 list_del_init(&ssp->eh_list_node);
779                 dev = container_of(ssp, typeof(*dev), ssp_dev);
780                 kref_get(&dev->kref);
781                 WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
782
783                 spin_unlock_irq(&ha->lock);
784
785                 if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
786                         i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
787
788                 if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
789                         i->dft->lldd_I_T_nexus_reset(dev);
790
791                 sas_put_device(dev);
792                 spin_lock_irq(&ha->lock);
793                 clear_bit(SAS_DEV_EH_PENDING, &dev->state);
794                 ha->eh_active--;
795         }
796         spin_unlock_irq(&ha->lock);
797 }
798
799
800 void sas_scsi_recover_host(struct Scsi_Host *shost)
801 {
802         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
803         LIST_HEAD(eh_work_q);
804         int tries = 0;
805         bool retry;
806
807 retry:
808         tries++;
809         retry = true;
810         spin_lock_irq(shost->host_lock);
811         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
812         spin_unlock_irq(shost->host_lock);
813
814         SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
815                     __func__, shost->host_busy, shost->host_failed);
816         /*
817          * Deal with commands that still have SAS tasks (i.e. they didn't
818          * complete via the normal sas_task completion mechanism),
819          * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
820          */
821         set_bit(SAS_HA_FROZEN, &ha->state);
822         sas_eh_handle_sas_errors(shost, &eh_work_q);
823         clear_bit(SAS_HA_FROZEN, &ha->state);
824         if (list_empty(&eh_work_q))
825                 goto out;
826
827         /*
828          * Now deal with SCSI commands that completed ok but have a an error
829          * code (and hopefully sense data) attached.  This is roughly what
830          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
831          * command we see here has no sas_task and is thus unknown to the HA.
832          */
833         sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
834         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
835                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
836
837 out:
838         if (ha->lldd_max_execute_num > 1)
839                 wake_up_process(ha->core.queue_thread);
840
841         sas_eh_handle_resets(shost);
842
843         /* now link into libata eh --- if we have any ata devices */
844         sas_ata_strategy_handler(shost);
845
846         scsi_eh_flush_done_q(&ha->eh_done_q);
847
848         /* check if any new eh work was scheduled during the last run */
849         spin_lock_irq(&ha->lock);
850         if (ha->eh_active == 0) {
851                 shost->host_eh_scheduled = 0;
852                 retry = false;
853         }
854         spin_unlock_irq(&ha->lock);
855
856         if (retry)
857                 goto retry;
858
859         SAS_DPRINTK("--- Exit %s: busy: %d failed: %d tries: %d\n",
860                     __func__, shost->host_busy, shost->host_failed, tries);
861 }
862
863 enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
864 {
865         scmd_printk(KERN_DEBUG, cmd, "command %p timed out\n", cmd);
866
867         return BLK_EH_NOT_HANDLED;
868 }
869
870 int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
871 {
872         struct domain_device *dev = sdev_to_domain_dev(sdev);
873
874         if (dev_is_sata(dev))
875                 return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
876
877         return -EINVAL;
878 }
879
880 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
881 {
882         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
883         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
884         struct domain_device *found_dev = NULL;
885         int i;
886         unsigned long flags;
887
888         spin_lock_irqsave(&ha->phy_port_lock, flags);
889         for (i = 0; i < ha->num_phys; i++) {
890                 struct asd_sas_port *port = ha->sas_port[i];
891                 struct domain_device *dev;
892
893                 spin_lock(&port->dev_list_lock);
894                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
895                         if (rphy == dev->rphy) {
896                                 found_dev = dev;
897                                 spin_unlock(&port->dev_list_lock);
898                                 goto found;
899                         }
900                 }
901                 spin_unlock(&port->dev_list_lock);
902         }
903  found:
904         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
905
906         return found_dev;
907 }
908
909 int sas_target_alloc(struct scsi_target *starget)
910 {
911         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
912         struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
913
914         if (!found_dev)
915                 return -ENODEV;
916
917         kref_get(&found_dev->kref);
918         starget->hostdata = found_dev;
919         return 0;
920 }
921
922 #define SAS_DEF_QD 256
923
924 int sas_slave_configure(struct scsi_device *scsi_dev)
925 {
926         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
927         struct sas_ha_struct *sas_ha;
928
929         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
930
931         if (dev_is_sata(dev)) {
932                 ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
933                 return 0;
934         }
935
936         sas_ha = dev->port->ha;
937
938         sas_read_port_mode_page(scsi_dev);
939
940         if (scsi_dev->tagged_supported) {
941                 scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
942                 scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
943         } else {
944                 SAS_DPRINTK("device %llx, LUN %x doesn't support "
945                             "TCQ\n", SAS_ADDR(dev->sas_addr),
946                             scsi_dev->lun);
947                 scsi_dev->tagged_supported = 0;
948                 scsi_set_tag_type(scsi_dev, 0);
949                 scsi_deactivate_tcq(scsi_dev, 1);
950         }
951
952         scsi_dev->allow_restart = 1;
953
954         return 0;
955 }
956
957 int sas_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
958 {
959         struct domain_device *dev = sdev_to_domain_dev(sdev);
960
961         if (dev_is_sata(dev))
962                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth,
963                                                 reason);
964
965         switch (reason) {
966         case SCSI_QDEPTH_DEFAULT:
967         case SCSI_QDEPTH_RAMP_UP:
968                 if (!sdev->tagged_supported)
969                         depth = 1;
970                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
971                 break;
972         case SCSI_QDEPTH_QFULL:
973                 scsi_track_queue_full(sdev, depth);
974                 break;
975         default:
976                 return -EOPNOTSUPP;
977         }
978
979         return depth;
980 }
981
982 int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
983 {
984         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
985
986         if (dev_is_sata(dev))
987                 return -EINVAL;
988
989         if (!scsi_dev->tagged_supported)
990                 return 0;
991
992         scsi_deactivate_tcq(scsi_dev, 1);
993
994         scsi_set_tag_type(scsi_dev, qt);
995         scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
996
997         return qt;
998 }
999
1000 int sas_bios_param(struct scsi_device *scsi_dev,
1001                           struct block_device *bdev,
1002                           sector_t capacity, int *hsc)
1003 {
1004         hsc[0] = 255;
1005         hsc[1] = 63;
1006         sector_div(capacity, 255*63);
1007         hsc[2] = capacity;
1008
1009         return 0;
1010 }
1011
1012 /* ---------- Task Collector Thread implementation ---------- */
1013
1014 static void sas_queue(struct sas_ha_struct *sas_ha)
1015 {
1016         struct scsi_core *core = &sas_ha->core;
1017         unsigned long flags;
1018         LIST_HEAD(q);
1019         int can_queue;
1020         int res;
1021         struct sas_internal *i = to_sas_internal(core->shost->transportt);
1022
1023         mutex_lock(&core->task_queue_flush);
1024         spin_lock_irqsave(&core->task_queue_lock, flags);
1025         while (!kthread_should_stop() &&
1026                !list_empty(&core->task_queue) &&
1027                !test_bit(SAS_HA_FROZEN, &sas_ha->state)) {
1028
1029                 can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
1030                 if (can_queue >= 0) {
1031                         can_queue = core->task_queue_size;
1032                         list_splice_init(&core->task_queue, &q);
1033                 } else {
1034                         struct list_head *a, *n;
1035
1036                         can_queue = sas_ha->lldd_queue_size;
1037                         list_for_each_safe(a, n, &core->task_queue) {
1038                                 list_move_tail(a, &q);
1039                                 if (--can_queue == 0)
1040                                         break;
1041                         }
1042                         can_queue = sas_ha->lldd_queue_size;
1043                 }
1044                 core->task_queue_size -= can_queue;
1045                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
1046                 {
1047                         struct sas_task *task = list_entry(q.next,
1048                                                            struct sas_task,
1049                                                            list);
1050                         list_del_init(&q);
1051                         res = i->dft->lldd_execute_task(task, can_queue,
1052                                                         GFP_KERNEL);
1053                         if (unlikely(res))
1054                                 __list_add(&q, task->list.prev, &task->list);
1055                 }
1056                 spin_lock_irqsave(&core->task_queue_lock, flags);
1057                 if (res) {
1058                         list_splice_init(&q, &core->task_queue); /*at head*/
1059                         core->task_queue_size += can_queue;
1060                 }
1061         }
1062         spin_unlock_irqrestore(&core->task_queue_lock, flags);
1063         mutex_unlock(&core->task_queue_flush);
1064 }
1065
1066 /**
1067  * sas_queue_thread -- The Task Collector thread
1068  * @_sas_ha: pointer to struct sas_ha
1069  */
1070 static int sas_queue_thread(void *_sas_ha)
1071 {
1072         struct sas_ha_struct *sas_ha = _sas_ha;
1073
1074         while (1) {
1075                 set_current_state(TASK_INTERRUPTIBLE);
1076                 schedule();
1077                 sas_queue(sas_ha);
1078                 if (kthread_should_stop())
1079                         break;
1080         }
1081
1082         return 0;
1083 }
1084
1085 int sas_init_queue(struct sas_ha_struct *sas_ha)
1086 {
1087         struct scsi_core *core = &sas_ha->core;
1088
1089         spin_lock_init(&core->task_queue_lock);
1090         mutex_init(&core->task_queue_flush);
1091         core->task_queue_size = 0;
1092         INIT_LIST_HEAD(&core->task_queue);
1093
1094         core->queue_thread = kthread_run(sas_queue_thread, sas_ha,
1095                                          "sas_queue_%d", core->shost->host_no);
1096         if (IS_ERR(core->queue_thread))
1097                 return PTR_ERR(core->queue_thread);
1098         return 0;
1099 }
1100
1101 void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
1102 {
1103         unsigned long flags;
1104         struct scsi_core *core = &sas_ha->core;
1105         struct sas_task *task, *n;
1106
1107         kthread_stop(core->queue_thread);
1108
1109         if (!list_empty(&core->task_queue))
1110                 SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
1111                             SAS_ADDR(sas_ha->sas_addr));
1112
1113         spin_lock_irqsave(&core->task_queue_lock, flags);
1114         list_for_each_entry_safe(task, n, &core->task_queue, list) {
1115                 struct scsi_cmnd *cmd = task->uldd_task;
1116
1117                 list_del_init(&task->list);
1118
1119                 ASSIGN_SAS_TASK(cmd, NULL);
1120                 sas_free_task(task);
1121                 cmd->result = DID_ABORT << 16;
1122                 cmd->scsi_done(cmd);
1123         }
1124         spin_unlock_irqrestore(&core->task_queue_lock, flags);
1125 }
1126
1127 /*
1128  * Tell an upper layer that it needs to initiate an abort for a given task.
1129  * This should only ever be called by an LLDD.
1130  */
1131 void sas_task_abort(struct sas_task *task)
1132 {
1133         struct scsi_cmnd *sc = task->uldd_task;
1134
1135         /* Escape for libsas internal commands */
1136         if (!sc) {
1137                 struct sas_task_slow *slow = task->slow_task;
1138
1139                 if (!slow)
1140                         return;
1141                 if (!del_timer(&slow->timer))
1142                         return;
1143                 slow->timer.function(slow->timer.data);
1144                 return;
1145         }
1146
1147         if (dev_is_sata(task->dev)) {
1148                 sas_ata_task_abort(task);
1149         } else {
1150                 struct request_queue *q = sc->device->request_queue;
1151                 unsigned long flags;
1152
1153                 spin_lock_irqsave(q->queue_lock, flags);
1154                 blk_abort_request(sc->request);
1155                 spin_unlock_irqrestore(q->queue_lock, flags);
1156         }
1157 }
1158
1159 void sas_target_destroy(struct scsi_target *starget)
1160 {
1161         struct domain_device *found_dev = starget->hostdata;
1162
1163         if (!found_dev)
1164                 return;
1165
1166         starget->hostdata = NULL;
1167         sas_put_device(found_dev);
1168 }
1169
1170 static void sas_parse_addr(u8 *sas_addr, const char *p)
1171 {
1172         int i;
1173         for (i = 0; i < SAS_ADDR_SIZE; i++) {
1174                 u8 h, l;
1175                 if (!*p)
1176                         break;
1177                 h = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
1178                 p++;
1179                 l = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
1180                 p++;
1181                 sas_addr[i] = (h<<4) | l;
1182         }
1183 }
1184
1185 #define SAS_STRING_ADDR_SIZE    16
1186
1187 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
1188 {
1189         int res;
1190         const struct firmware *fw;
1191
1192         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
1193         if (res)
1194                 return res;
1195
1196         if (fw->size < SAS_STRING_ADDR_SIZE) {
1197                 res = -ENODEV;
1198                 goto out;
1199         }
1200
1201         sas_parse_addr(addr, fw->data);
1202
1203 out:
1204         release_firmware(fw);
1205         return res;
1206 }
1207 EXPORT_SYMBOL_GPL(sas_request_addr);
1208
1209 EXPORT_SYMBOL_GPL(sas_queuecommand);
1210 EXPORT_SYMBOL_GPL(sas_target_alloc);
1211 EXPORT_SYMBOL_GPL(sas_slave_configure);
1212 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
1213 EXPORT_SYMBOL_GPL(sas_change_queue_type);
1214 EXPORT_SYMBOL_GPL(sas_bios_param);
1215 EXPORT_SYMBOL_GPL(sas_task_abort);
1216 EXPORT_SYMBOL_GPL(sas_phy_reset);
1217 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
1218 EXPORT_SYMBOL_GPL(sas_eh_bus_reset_handler);
1219 EXPORT_SYMBOL_GPL(sas_target_destroy);
1220 EXPORT_SYMBOL_GPL(sas_ioctl);