Merge tag 'nfsd-4.16-1' of git://linux-nfs.org/~bfields/linux
[muen/linux.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 <linux/kthread.h>
27 #include <linux/firmware.h>
28 #include <linux/export.h>
29 #include <linux/ctype.h>
30 #include <linux/kernel.h>
31
32 #include "sas_internal.h"
33
34 #include <scsi/scsi_host.h>
35 #include <scsi/scsi_device.h>
36 #include <scsi/scsi_tcq.h>
37 #include <scsi/scsi.h>
38 #include <scsi/scsi_eh.h>
39 #include <scsi/scsi_transport.h>
40 #include <scsi/scsi_transport_sas.h>
41 #include <scsi/sas_ata.h>
42 #include "../scsi_sas_internal.h"
43 #include "../scsi_transport_api.h"
44 #include "../scsi_priv.h"
45
46 #include <linux/err.h>
47 #include <linux/blkdev.h>
48 #include <linux/freezer.h>
49 #include <linux/gfp.h>
50 #include <linux/scatterlist.h>
51 #include <linux/libata.h>
52
53 /* record final status and free the task */
54 static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
55 {
56         struct task_status_struct *ts = &task->task_status;
57         int hs = 0, stat = 0;
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                         scsi_set_resid(sc, ts->residual);
74                         if (scsi_bufflen(sc) - scsi_get_resid(sc) < 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_STAT_CHECK_CONDITION:
104                         memcpy(sc->sense_buffer, ts->buf,
105                                min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
106                         stat = SAM_STAT_CHECK_CONDITION;
107                         break;
108                 default:
109                         stat = ts->stat;
110                         break;
111                 }
112         }
113
114         sc->result = (hs << 16) | stat;
115         ASSIGN_SAS_TASK(sc, NULL);
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                 sas_free_task(task);
142                 return;
143         }
144
145         sas_end_task(sc, task);
146         sc->scsi_done(sc);
147 }
148
149 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
150                                                struct domain_device *dev,
151                                                gfp_t gfp_flags)
152 {
153         struct sas_task *task = sas_alloc_task(gfp_flags);
154         struct scsi_lun lun;
155
156         if (!task)
157                 return NULL;
158
159         task->uldd_task = cmd;
160         ASSIGN_SAS_TASK(cmd, task);
161
162         task->dev = dev;
163         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
164
165         task->ssp_task.retry_count = 1;
166         int_to_scsilun(cmd->device->lun, &lun);
167         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
168         task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
169         task->ssp_task.cmd = cmd;
170
171         task->scatter = scsi_sglist(cmd);
172         task->num_scatter = scsi_sg_count(cmd);
173         task->total_xfer_len = scsi_bufflen(cmd);
174         task->data_dir = cmd->sc_data_direction;
175
176         task->task_done = sas_scsi_task_done;
177
178         return task;
179 }
180
181 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
182 {
183         struct sas_internal *i = to_sas_internal(host->transportt);
184         struct domain_device *dev = cmd_to_domain_dev(cmd);
185         struct sas_task *task;
186         int res = 0;
187
188         /* If the device fell off, no sense in issuing commands */
189         if (test_bit(SAS_DEV_GONE, &dev->state)) {
190                 cmd->result = DID_BAD_TARGET << 16;
191                 goto out_done;
192         }
193
194         if (dev_is_sata(dev)) {
195                 spin_lock_irq(dev->sata_dev.ap->lock);
196                 res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
197                 spin_unlock_irq(dev->sata_dev.ap->lock);
198                 return res;
199         }
200
201         task = sas_create_task(cmd, dev, GFP_ATOMIC);
202         if (!task)
203                 return SCSI_MLQUEUE_HOST_BUSY;
204
205         res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
206         if (res)
207                 goto out_free_task;
208         return 0;
209
210 out_free_task:
211         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
212         ASSIGN_SAS_TASK(cmd, NULL);
213         sas_free_task(task);
214         if (res == -SAS_QUEUE_FULL)
215                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
216         else
217                 cmd->result = DID_ERROR << 16;
218 out_done:
219         cmd->scsi_done(cmd);
220         return 0;
221 }
222
223 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
224 {
225         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
226         struct sas_task *task = TO_SAS_TASK(cmd);
227
228         /* At this point, we only get called following an actual abort
229          * of the task, so we should be guaranteed not to be racing with
230          * any completions from the LLD.  Task is freed after this.
231          */
232         sas_end_task(cmd, task);
233
234         /* now finish the command and move it on to the error
235          * handler done list, this also takes it off the
236          * error handler pending list.
237          */
238         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
239 }
240
241 static void sas_eh_defer_cmd(struct scsi_cmnd *cmd)
242 {
243         struct domain_device *dev = cmd_to_domain_dev(cmd);
244         struct sas_ha_struct *ha = dev->port->ha;
245         struct sas_task *task = TO_SAS_TASK(cmd);
246
247         if (!dev_is_sata(dev)) {
248                 sas_eh_finish_cmd(cmd);
249                 return;
250         }
251
252         /* report the timeout to libata */
253         sas_end_task(cmd, task);
254         list_move_tail(&cmd->eh_entry, &ha->eh_ata_q);
255 }
256
257 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
258 {
259         struct scsi_cmnd *cmd, *n;
260
261         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
262                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
263                     cmd->device->lun == my_cmd->device->lun)
264                         sas_eh_defer_cmd(cmd);
265         }
266 }
267
268 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
269                                      struct domain_device *dev)
270 {
271         struct scsi_cmnd *cmd, *n;
272
273         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
274                 struct domain_device *x = cmd_to_domain_dev(cmd);
275
276                 if (x == dev)
277                         sas_eh_finish_cmd(cmd);
278         }
279 }
280
281 static void sas_scsi_clear_queue_port(struct list_head *error_q,
282                                       struct asd_sas_port *port)
283 {
284         struct scsi_cmnd *cmd, *n;
285
286         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
287                 struct domain_device *dev = cmd_to_domain_dev(cmd);
288                 struct asd_sas_port *x = dev->port;
289
290                 if (x == port)
291                         sas_eh_finish_cmd(cmd);
292         }
293 }
294
295 enum task_disposition {
296         TASK_IS_DONE,
297         TASK_IS_ABORTED,
298         TASK_IS_AT_LU,
299         TASK_IS_NOT_AT_LU,
300         TASK_ABORT_FAILED,
301 };
302
303 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
304 {
305         unsigned long flags;
306         int i, res;
307         struct sas_internal *si =
308                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
309
310         for (i = 0; i < 5; i++) {
311                 SAS_DPRINTK("%s: aborting task 0x%p\n", __func__, 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", __func__,
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                                     __func__, task);
326                         return TASK_IS_ABORTED;
327                 } else if (si->dft->lldd_query_task) {
328                         SAS_DPRINTK("%s: querying task 0x%p\n",
329                                     __func__, task);
330                         res = si->dft->lldd_query_task(task);
331                         switch (res) {
332                         case TMF_RESP_FUNC_SUCC:
333                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
334                                             __func__, task);
335                                 return TASK_IS_AT_LU;
336                         case TMF_RESP_FUNC_COMPLETE:
337                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
338                                             __func__, task);
339                                 return TASK_IS_NOT_AT_LU;
340                         case TMF_RESP_FUNC_FAILED:
341                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
342                                                 __func__, task);
343                                 return TASK_ABORT_FAILED;
344                         }
345
346                 }
347         }
348         return res;
349 }
350
351 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
352 {
353         int res = TMF_RESP_FUNC_FAILED;
354         struct scsi_lun lun;
355         struct sas_internal *i =
356                 to_sas_internal(dev->port->ha->core.shost->transportt);
357
358         int_to_scsilun(cmd->device->lun, &lun);
359
360         SAS_DPRINTK("eh: device %llx LUN %llx has the task\n",
361                     SAS_ADDR(dev->sas_addr),
362                     cmd->device->lun);
363
364         if (i->dft->lldd_abort_task_set)
365                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
366
367         if (res == TMF_RESP_FUNC_FAILED) {
368                 if (i->dft->lldd_clear_task_set)
369                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
370         }
371
372         if (res == TMF_RESP_FUNC_FAILED) {
373                 if (i->dft->lldd_lu_reset)
374                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
375         }
376
377         return res;
378 }
379
380 static int sas_recover_I_T(struct domain_device *dev)
381 {
382         int res = TMF_RESP_FUNC_FAILED;
383         struct sas_internal *i =
384                 to_sas_internal(dev->port->ha->core.shost->transportt);
385
386         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
387                     SAS_ADDR(dev->sas_addr));
388
389         if (i->dft->lldd_I_T_nexus_reset)
390                 res = i->dft->lldd_I_T_nexus_reset(dev);
391
392         return res;
393 }
394
395 /* take a reference on the last known good phy for this device */
396 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
397 {
398         struct sas_ha_struct *ha = dev->port->ha;
399         struct sas_phy *phy;
400         unsigned long flags;
401
402         /* a published domain device always has a valid phy, it may be
403          * stale, but it is never NULL
404          */
405         BUG_ON(!dev->phy);
406
407         spin_lock_irqsave(&ha->phy_port_lock, flags);
408         phy = dev->phy;
409         get_device(&phy->dev);
410         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
411
412         return phy;
413 }
414 EXPORT_SYMBOL_GPL(sas_get_local_phy);
415
416 static void sas_wait_eh(struct domain_device *dev)
417 {
418         struct sas_ha_struct *ha = dev->port->ha;
419         DEFINE_WAIT(wait);
420
421         if (dev_is_sata(dev)) {
422                 ata_port_wait_eh(dev->sata_dev.ap);
423                 return;
424         }
425  retry:
426         spin_lock_irq(&ha->lock);
427
428         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
429                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
430                 spin_unlock_irq(&ha->lock);
431                 schedule();
432                 spin_lock_irq(&ha->lock);
433         }
434         finish_wait(&ha->eh_wait_q, &wait);
435
436         spin_unlock_irq(&ha->lock);
437
438         /* make sure SCSI EH is complete */
439         if (scsi_host_in_recovery(ha->core.shost)) {
440                 msleep(10);
441                 goto retry;
442         }
443 }
444 EXPORT_SYMBOL(sas_wait_eh);
445
446 static int sas_queue_reset(struct domain_device *dev, int reset_type,
447                            u64 lun, int wait)
448 {
449         struct sas_ha_struct *ha = dev->port->ha;
450         int scheduled = 0, tries = 100;
451
452         /* ata: promote lun reset to bus reset */
453         if (dev_is_sata(dev)) {
454                 sas_ata_schedule_reset(dev);
455                 if (wait)
456                         sas_ata_wait_eh(dev);
457                 return SUCCESS;
458         }
459
460         while (!scheduled && tries--) {
461                 spin_lock_irq(&ha->lock);
462                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
463                     !test_bit(reset_type, &dev->state)) {
464                         scheduled = 1;
465                         ha->eh_active++;
466                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
467                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
468                         set_bit(reset_type, &dev->state);
469                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
470                         scsi_schedule_eh(ha->core.shost);
471                 }
472                 spin_unlock_irq(&ha->lock);
473
474                 if (wait)
475                         sas_wait_eh(dev);
476
477                 if (scheduled)
478                         return SUCCESS;
479         }
480
481         SAS_DPRINTK("%s reset of %s failed\n",
482                     reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
483                     dev_name(&dev->rphy->dev));
484
485         return FAILED;
486 }
487
488 int sas_eh_abort_handler(struct scsi_cmnd *cmd)
489 {
490         int res = TMF_RESP_FUNC_FAILED;
491         struct sas_task *task = TO_SAS_TASK(cmd);
492         struct Scsi_Host *host = cmd->device->host;
493         struct domain_device *dev = cmd_to_domain_dev(cmd);
494         struct sas_internal *i = to_sas_internal(host->transportt);
495         unsigned long flags;
496
497         if (!i->dft->lldd_abort_task)
498                 return FAILED;
499
500         spin_lock_irqsave(host->host_lock, flags);
501         /* We cannot do async aborts for SATA devices */
502         if (dev_is_sata(dev) && !host->host_eh_scheduled) {
503                 spin_unlock_irqrestore(host->host_lock, flags);
504                 return FAILED;
505         }
506         spin_unlock_irqrestore(host->host_lock, flags);
507
508         if (task)
509                 res = i->dft->lldd_abort_task(task);
510         else
511                 SAS_DPRINTK("no task to abort\n");
512         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
513                 return SUCCESS;
514
515         return FAILED;
516 }
517 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
518
519 /* Attempt to send a LUN reset message to a device */
520 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
521 {
522         int res;
523         struct scsi_lun lun;
524         struct Scsi_Host *host = cmd->device->host;
525         struct domain_device *dev = cmd_to_domain_dev(cmd);
526         struct sas_internal *i = to_sas_internal(host->transportt);
527
528         if (current != host->ehandler)
529                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
530
531         int_to_scsilun(cmd->device->lun, &lun);
532
533         if (!i->dft->lldd_lu_reset)
534                 return FAILED;
535
536         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
537         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
538                 return SUCCESS;
539
540         return FAILED;
541 }
542
543 int sas_eh_target_reset_handler(struct scsi_cmnd *cmd)
544 {
545         int res;
546         struct Scsi_Host *host = cmd->device->host;
547         struct domain_device *dev = cmd_to_domain_dev(cmd);
548         struct sas_internal *i = to_sas_internal(host->transportt);
549
550         if (current != host->ehandler)
551                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
552
553         if (!i->dft->lldd_I_T_nexus_reset)
554                 return FAILED;
555
556         res = i->dft->lldd_I_T_nexus_reset(dev);
557         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
558             res == -ENODEV)
559                 return SUCCESS;
560
561         return FAILED;
562 }
563
564 /* Try to reset a device */
565 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
566 {
567         int res;
568         struct Scsi_Host *shost = cmd->device->host;
569
570         if (!shost->hostt->eh_device_reset_handler)
571                 goto try_target_reset;
572
573         res = shost->hostt->eh_device_reset_handler(cmd);
574         if (res == SUCCESS)
575                 return res;
576
577 try_target_reset:
578         if (shost->hostt->eh_target_reset_handler)
579                 return shost->hostt->eh_target_reset_handler(cmd);
580
581         return FAILED;
582 }
583
584 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
585 {
586         struct scsi_cmnd *cmd, *n;
587         enum task_disposition res = TASK_IS_DONE;
588         int tmf_resp, need_reset;
589         struct sas_internal *i = to_sas_internal(shost->transportt);
590         unsigned long flags;
591         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
592         LIST_HEAD(done);
593
594         /* clean out any commands that won the completion vs eh race */
595         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
596                 struct domain_device *dev = cmd_to_domain_dev(cmd);
597                 struct sas_task *task;
598
599                 spin_lock_irqsave(&dev->done_lock, flags);
600                 /* by this point the lldd has either observed
601                  * SAS_HA_FROZEN and is leaving the task alone, or has
602                  * won the race with eh and decided to complete it
603                  */
604                 task = TO_SAS_TASK(cmd);
605                 spin_unlock_irqrestore(&dev->done_lock, flags);
606
607                 if (!task)
608                         list_move_tail(&cmd->eh_entry, &done);
609         }
610
611  Again:
612         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
613                 struct sas_task *task = TO_SAS_TASK(cmd);
614
615                 list_del_init(&cmd->eh_entry);
616
617                 spin_lock_irqsave(&task->task_state_lock, flags);
618                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
619                 spin_unlock_irqrestore(&task->task_state_lock, flags);
620
621                 if (need_reset) {
622                         SAS_DPRINTK("%s: task 0x%p requests reset\n",
623                                     __func__, task);
624                         goto reset;
625                 }
626
627                 SAS_DPRINTK("trying to find task 0x%p\n", task);
628                 res = sas_scsi_find_task(task);
629
630                 switch (res) {
631                 case TASK_IS_DONE:
632                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
633                                     task);
634                         sas_eh_defer_cmd(cmd);
635                         continue;
636                 case TASK_IS_ABORTED:
637                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
638                                     __func__, task);
639                         sas_eh_defer_cmd(cmd);
640                         continue;
641                 case TASK_IS_AT_LU:
642                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
643  reset:
644                         tmf_resp = sas_recover_lu(task->dev, cmd);
645                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
646                                 SAS_DPRINTK("dev %016llx LU %llx is "
647                                             "recovered\n",
648                                             SAS_ADDR(task->dev),
649                                             cmd->device->lun);
650                                 sas_eh_defer_cmd(cmd);
651                                 sas_scsi_clear_queue_lu(work_q, cmd);
652                                 goto Again;
653                         }
654                         /* fallthrough */
655                 case TASK_IS_NOT_AT_LU:
656                 case TASK_ABORT_FAILED:
657                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
658                                     task);
659                         tmf_resp = sas_recover_I_T(task->dev);
660                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
661                             tmf_resp == -ENODEV) {
662                                 struct domain_device *dev = task->dev;
663                                 SAS_DPRINTK("I_T %016llx recovered\n",
664                                             SAS_ADDR(task->dev->sas_addr));
665                                 sas_eh_finish_cmd(cmd);
666                                 sas_scsi_clear_queue_I_T(work_q, dev);
667                                 goto Again;
668                         }
669                         /* Hammer time :-) */
670                         try_to_reset_cmd_device(cmd);
671                         if (i->dft->lldd_clear_nexus_port) {
672                                 struct asd_sas_port *port = task->dev->port;
673                                 SAS_DPRINTK("clearing nexus for port:%d\n",
674                                             port->id);
675                                 res = i->dft->lldd_clear_nexus_port(port);
676                                 if (res == TMF_RESP_FUNC_COMPLETE) {
677                                         SAS_DPRINTK("clear nexus port:%d "
678                                                     "succeeded\n", port->id);
679                                         sas_eh_finish_cmd(cmd);
680                                         sas_scsi_clear_queue_port(work_q,
681                                                                   port);
682                                         goto Again;
683                                 }
684                         }
685                         if (i->dft->lldd_clear_nexus_ha) {
686                                 SAS_DPRINTK("clear nexus ha\n");
687                                 res = i->dft->lldd_clear_nexus_ha(ha);
688                                 if (res == TMF_RESP_FUNC_COMPLETE) {
689                                         SAS_DPRINTK("clear nexus ha "
690                                                     "succeeded\n");
691                                         sas_eh_finish_cmd(cmd);
692                                         goto clear_q;
693                                 }
694                         }
695                         /* If we are here -- this means that no amount
696                          * of effort could recover from errors.  Quite
697                          * possibly the HA just disappeared.
698                          */
699                         SAS_DPRINTK("error from  device %llx, LUN %llx "
700                                     "couldn't be recovered in any way\n",
701                                     SAS_ADDR(task->dev->sas_addr),
702                                     cmd->device->lun);
703
704                         sas_eh_finish_cmd(cmd);
705                         goto clear_q;
706                 }
707         }
708  out:
709         list_splice_tail(&done, work_q);
710         list_splice_tail_init(&ha->eh_ata_q, work_q);
711         return;
712
713  clear_q:
714         SAS_DPRINTK("--- Exit %s -- clear_q\n", __func__);
715         list_for_each_entry_safe(cmd, n, work_q, eh_entry)
716                 sas_eh_finish_cmd(cmd);
717         goto out;
718 }
719
720 static void sas_eh_handle_resets(struct Scsi_Host *shost)
721 {
722         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
723         struct sas_internal *i = to_sas_internal(shost->transportt);
724
725         /* handle directed resets to sas devices */
726         spin_lock_irq(&ha->lock);
727         while (!list_empty(&ha->eh_dev_q)) {
728                 struct domain_device *dev;
729                 struct ssp_device *ssp;
730
731                 ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
732                 list_del_init(&ssp->eh_list_node);
733                 dev = container_of(ssp, typeof(*dev), ssp_dev);
734                 kref_get(&dev->kref);
735                 WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
736
737                 spin_unlock_irq(&ha->lock);
738
739                 if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
740                         i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
741
742                 if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
743                         i->dft->lldd_I_T_nexus_reset(dev);
744
745                 sas_put_device(dev);
746                 spin_lock_irq(&ha->lock);
747                 clear_bit(SAS_DEV_EH_PENDING, &dev->state);
748                 ha->eh_active--;
749         }
750         spin_unlock_irq(&ha->lock);
751 }
752
753
754 void sas_scsi_recover_host(struct Scsi_Host *shost)
755 {
756         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
757         LIST_HEAD(eh_work_q);
758         int tries = 0;
759         bool retry;
760
761 retry:
762         tries++;
763         retry = true;
764         spin_lock_irq(shost->host_lock);
765         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
766         spin_unlock_irq(shost->host_lock);
767
768         SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
769                     __func__, atomic_read(&shost->host_busy), shost->host_failed);
770         /*
771          * Deal with commands that still have SAS tasks (i.e. they didn't
772          * complete via the normal sas_task completion mechanism),
773          * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
774          */
775         set_bit(SAS_HA_FROZEN, &ha->state);
776         sas_eh_handle_sas_errors(shost, &eh_work_q);
777         clear_bit(SAS_HA_FROZEN, &ha->state);
778         if (list_empty(&eh_work_q))
779                 goto out;
780
781         /*
782          * Now deal with SCSI commands that completed ok but have a an error
783          * code (and hopefully sense data) attached.  This is roughly what
784          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
785          * command we see here has no sas_task and is thus unknown to the HA.
786          */
787         sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
788         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
789                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
790
791 out:
792         sas_eh_handle_resets(shost);
793
794         /* now link into libata eh --- if we have any ata devices */
795         sas_ata_strategy_handler(shost);
796
797         scsi_eh_flush_done_q(&ha->eh_done_q);
798
799         /* check if any new eh work was scheduled during the last run */
800         spin_lock_irq(&ha->lock);
801         if (ha->eh_active == 0) {
802                 shost->host_eh_scheduled = 0;
803                 retry = false;
804         }
805         spin_unlock_irq(&ha->lock);
806
807         if (retry)
808                 goto retry;
809
810         SAS_DPRINTK("--- Exit %s: busy: %d failed: %d tries: %d\n",
811                     __func__, atomic_read(&shost->host_busy),
812                     shost->host_failed, tries);
813 }
814
815 int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
816 {
817         struct domain_device *dev = sdev_to_domain_dev(sdev);
818
819         if (dev_is_sata(dev))
820                 return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
821
822         return -EINVAL;
823 }
824
825 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
826 {
827         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
828         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
829         struct domain_device *found_dev = NULL;
830         int i;
831         unsigned long flags;
832
833         spin_lock_irqsave(&ha->phy_port_lock, flags);
834         for (i = 0; i < ha->num_phys; i++) {
835                 struct asd_sas_port *port = ha->sas_port[i];
836                 struct domain_device *dev;
837
838                 spin_lock(&port->dev_list_lock);
839                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
840                         if (rphy == dev->rphy) {
841                                 found_dev = dev;
842                                 spin_unlock(&port->dev_list_lock);
843                                 goto found;
844                         }
845                 }
846                 spin_unlock(&port->dev_list_lock);
847         }
848  found:
849         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
850
851         return found_dev;
852 }
853
854 int sas_target_alloc(struct scsi_target *starget)
855 {
856         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
857         struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
858
859         if (!found_dev)
860                 return -ENODEV;
861
862         kref_get(&found_dev->kref);
863         starget->hostdata = found_dev;
864         return 0;
865 }
866
867 #define SAS_DEF_QD 256
868
869 int sas_slave_configure(struct scsi_device *scsi_dev)
870 {
871         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
872
873         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
874
875         if (dev_is_sata(dev)) {
876                 ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
877                 return 0;
878         }
879
880         sas_read_port_mode_page(scsi_dev);
881
882         if (scsi_dev->tagged_supported) {
883                 scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
884         } else {
885                 SAS_DPRINTK("device %llx, LUN %llx doesn't support "
886                             "TCQ\n", SAS_ADDR(dev->sas_addr),
887                             scsi_dev->lun);
888                 scsi_change_queue_depth(scsi_dev, 1);
889         }
890
891         scsi_dev->allow_restart = 1;
892
893         return 0;
894 }
895
896 int sas_change_queue_depth(struct scsi_device *sdev, int depth)
897 {
898         struct domain_device *dev = sdev_to_domain_dev(sdev);
899
900         if (dev_is_sata(dev))
901                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
902
903         if (!sdev->tagged_supported)
904                 depth = 1;
905         return scsi_change_queue_depth(sdev, depth);
906 }
907
908 int sas_bios_param(struct scsi_device *scsi_dev,
909                           struct block_device *bdev,
910                           sector_t capacity, int *hsc)
911 {
912         hsc[0] = 255;
913         hsc[1] = 63;
914         sector_div(capacity, 255*63);
915         hsc[2] = capacity;
916
917         return 0;
918 }
919
920 /*
921  * Tell an upper layer that it needs to initiate an abort for a given task.
922  * This should only ever be called by an LLDD.
923  */
924 void sas_task_abort(struct sas_task *task)
925 {
926         struct scsi_cmnd *sc = task->uldd_task;
927
928         /* Escape for libsas internal commands */
929         if (!sc) {
930                 struct sas_task_slow *slow = task->slow_task;
931
932                 if (!slow)
933                         return;
934                 if (!del_timer(&slow->timer))
935                         return;
936                 slow->timer.function(&slow->timer);
937                 return;
938         }
939
940         if (dev_is_sata(task->dev)) {
941                 sas_ata_task_abort(task);
942         } else {
943                 struct request_queue *q = sc->device->request_queue;
944                 unsigned long flags;
945
946                 spin_lock_irqsave(q->queue_lock, flags);
947                 blk_abort_request(sc->request);
948                 spin_unlock_irqrestore(q->queue_lock, flags);
949         }
950 }
951
952 void sas_target_destroy(struct scsi_target *starget)
953 {
954         struct domain_device *found_dev = starget->hostdata;
955
956         if (!found_dev)
957                 return;
958
959         starget->hostdata = NULL;
960         sas_put_device(found_dev);
961 }
962
963 #define SAS_STRING_ADDR_SIZE    16
964
965 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
966 {
967         int res;
968         const struct firmware *fw;
969
970         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
971         if (res)
972                 return res;
973
974         if (fw->size < SAS_STRING_ADDR_SIZE) {
975                 res = -ENODEV;
976                 goto out;
977         }
978
979         res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
980         if (res)
981                 goto out;
982
983 out:
984         release_firmware(fw);
985         return res;
986 }
987 EXPORT_SYMBOL_GPL(sas_request_addr);
988
989 EXPORT_SYMBOL_GPL(sas_queuecommand);
990 EXPORT_SYMBOL_GPL(sas_target_alloc);
991 EXPORT_SYMBOL_GPL(sas_slave_configure);
992 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
993 EXPORT_SYMBOL_GPL(sas_bios_param);
994 EXPORT_SYMBOL_GPL(sas_task_abort);
995 EXPORT_SYMBOL_GPL(sas_phy_reset);
996 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
997 EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
998 EXPORT_SYMBOL_GPL(sas_target_destroy);
999 EXPORT_SYMBOL_GPL(sas_ioctl);