700708c82678277a3b4640d2f729ef35087702d3
[linux-2.6.git] / drivers / scsi / isci / task.c
1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  * redistributing this file, you may do so under either license.
4  *
5  * GPL LICENSE SUMMARY
6  *
7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
21  * The full GNU General Public License is included in this distribution
22  * in the file called LICENSE.GPL.
23  *
24  * BSD LICENSE
25  *
26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
27  * All rights reserved.
28  *
29  * Redistribution and use in source and binary forms, with or without
30  * modification, are permitted provided that the following conditions
31  * are met:
32  *
33  *   * Redistributions of source code must retain the above copyright
34  *     notice, this list of conditions and the following disclaimer.
35  *   * Redistributions in binary form must reproduce the above copyright
36  *     notice, this list of conditions and the following disclaimer in
37  *     the documentation and/or other materials provided with the
38  *     distribution.
39  *   * Neither the name of Intel Corporation nor the names of its
40  *     contributors may be used to endorse or promote products derived
41  *     from this software without specific prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
54  */
55
56 #include <linux/completion.h>
57 #include <linux/irqflags.h>
58 #include "sas.h"
59 #include <scsi/libsas.h>
60 #include "remote_device.h"
61 #include "remote_node_context.h"
62 #include "isci.h"
63 #include "request.h"
64 #include "sata.h"
65 #include "task.h"
66 #include "host.h"
67
68 /**
69 * isci_task_refuse() - complete the request to the upper layer driver in
70 *     the case where an I/O needs to be completed back in the submit path.
71 * @ihost: host on which the the request was queued
72 * @task: request to complete
73 * @response: response code for the completed task.
74 * @status: status code for the completed task.
75 *
76 */
77 static void isci_task_refuse(struct isci_host *ihost, struct sas_task *task,
78                              enum service_response response,
79                              enum exec_status status)
80
81 {
82         enum isci_completion_selection disposition;
83
84         disposition = isci_perform_normal_io_completion;
85         disposition = isci_task_set_completion_status(task, response, status,
86                                                       disposition);
87
88         /* Tasks aborted specifically by a call to the lldd_abort_task
89          * function should not be completed to the host in the regular path.
90          */
91         switch (disposition) {
92                 case isci_perform_normal_io_completion:
93                         /* Normal notification (task_done) */
94                         dev_dbg(&ihost->pdev->dev,
95                                 "%s: Normal - task = %p, response=%d, "
96                                 "status=%d\n",
97                                 __func__, task, response, status);
98
99                         task->lldd_task = NULL;
100
101                         isci_execpath_callback(ihost, task, task->task_done);
102                         break;
103
104                 case isci_perform_aborted_io_completion:
105                         /* No notification because this request is already in the
106                         * abort path.
107                         */
108                         dev_warn(&ihost->pdev->dev,
109                                  "%s: Aborted - task = %p, response=%d, "
110                                 "status=%d\n",
111                                  __func__, task, response, status);
112                         break;
113
114                 case isci_perform_error_io_completion:
115                         /* Use sas_task_abort */
116                         dev_warn(&ihost->pdev->dev,
117                                  "%s: Error - task = %p, response=%d, "
118                                 "status=%d\n",
119                                  __func__, task, response, status);
120
121                         isci_execpath_callback(ihost, task, sas_task_abort);
122                         break;
123
124                 default:
125                         dev_warn(&ihost->pdev->dev,
126                                  "%s: isci task notification default case!",
127                                  __func__);
128                         sas_task_abort(task);
129                         break;
130         }
131 }
132
133 #define for_each_sas_task(num, task) \
134         for (; num > 0; num--,\
135              task = list_entry(task->list.next, struct sas_task, list))
136
137
138 static inline int isci_device_io_ready(struct isci_remote_device *idev,
139                                        struct sas_task *task)
140 {
141         return idev ? test_bit(IDEV_IO_READY, &idev->flags) ||
142                       (test_bit(IDEV_IO_NCQERROR, &idev->flags) &&
143                        isci_task_is_ncq_recovery(task))
144                     : 0;
145 }
146 /**
147  * isci_task_execute_task() - This function is one of the SAS Domain Template
148  *    functions. This function is called by libsas to send a task down to
149  *    hardware.
150  * @task: This parameter specifies the SAS task to send.
151  * @num: This parameter specifies the number of tasks to queue.
152  * @gfp_flags: This parameter specifies the context of this call.
153  *
154  * status, zero indicates success.
155  */
156 int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags)
157 {
158         struct isci_host *ihost = dev_to_ihost(task->dev);
159         struct isci_remote_device *idev;
160         unsigned long flags;
161         bool io_ready;
162         u16 tag;
163
164         dev_dbg(&ihost->pdev->dev, "%s: num=%d\n", __func__, num);
165
166         for_each_sas_task(num, task) {
167                 enum sci_status status = SCI_FAILURE;
168
169                 spin_lock_irqsave(&ihost->scic_lock, flags);
170                 idev = isci_lookup_device(task->dev);
171                 io_ready = isci_device_io_ready(idev, task);
172                 tag = isci_alloc_tag(ihost);
173                 spin_unlock_irqrestore(&ihost->scic_lock, flags);
174
175                 dev_dbg(&ihost->pdev->dev,
176                         "task: %p, num: %d dev: %p idev: %p:%#lx cmd = %p\n",
177                         task, num, task->dev, idev, idev ? idev->flags : 0,
178                         task->uldd_task);
179
180                 if (!idev) {
181                         isci_task_refuse(ihost, task, SAS_TASK_UNDELIVERED,
182                                          SAS_DEVICE_UNKNOWN);
183                 } else if (!io_ready || tag == SCI_CONTROLLER_INVALID_IO_TAG) {
184                         /* Indicate QUEUE_FULL so that the scsi midlayer
185                          * retries.
186                           */
187                         isci_task_refuse(ihost, task, SAS_TASK_COMPLETE,
188                                          SAS_QUEUE_FULL);
189                 } else {
190                         /* There is a device and it's ready for I/O. */
191                         spin_lock_irqsave(&task->task_state_lock, flags);
192
193                         if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
194                                 /* The I/O was aborted. */
195                                 spin_unlock_irqrestore(&task->task_state_lock,
196                                                        flags);
197
198                                 isci_task_refuse(ihost, task,
199                                                  SAS_TASK_UNDELIVERED,
200                                                  SAM_STAT_TASK_ABORTED);
201                         } else {
202                                 task->task_state_flags |= SAS_TASK_AT_INITIATOR;
203                                 spin_unlock_irqrestore(&task->task_state_lock, flags);
204
205                                 /* build and send the request. */
206                                 status = isci_request_execute(ihost, idev, task, tag);
207
208                                 if (status != SCI_SUCCESS) {
209
210                                         spin_lock_irqsave(&task->task_state_lock, flags);
211                                         /* Did not really start this command. */
212                                         task->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
213                                         spin_unlock_irqrestore(&task->task_state_lock, flags);
214
215                                         /* Indicate QUEUE_FULL so that the scsi
216                                         * midlayer retries. if the request
217                                         * failed for remote device reasons,
218                                         * it gets returned as
219                                         * SAS_TASK_UNDELIVERED next time
220                                         * through.
221                                         */
222                                         isci_task_refuse(ihost, task,
223                                                          SAS_TASK_COMPLETE,
224                                                          SAS_QUEUE_FULL);
225                                 }
226                         }
227                 }
228                 if (status != SCI_SUCCESS && tag != SCI_CONTROLLER_INVALID_IO_TAG) {
229                         spin_lock_irqsave(&ihost->scic_lock, flags);
230                         /* command never hit the device, so just free
231                          * the tci and skip the sequence increment
232                          */
233                         isci_tci_free(ihost, ISCI_TAG_TCI(tag));
234                         spin_unlock_irqrestore(&ihost->scic_lock, flags);
235                 }
236                 isci_put_device(idev);
237         }
238         return 0;
239 }
240
241 static struct isci_request *isci_task_request_build(struct isci_host *ihost,
242                                                     struct isci_remote_device *idev,
243                                                     u16 tag, struct isci_tmf *isci_tmf)
244 {
245         enum sci_status status = SCI_FAILURE;
246         struct isci_request *ireq = NULL;
247         struct domain_device *dev;
248
249         dev_dbg(&ihost->pdev->dev,
250                 "%s: isci_tmf = %p\n", __func__, isci_tmf);
251
252         dev = idev->domain_dev;
253
254         /* do common allocation and init of request object. */
255         ireq = isci_tmf_request_from_tag(ihost, isci_tmf, tag);
256         if (!ireq)
257                 return NULL;
258
259         /* let the core do it's construct. */
260         status = scic_task_request_construct(&ihost->sci, &idev->sci, tag,
261                                              ireq);
262
263         if (status != SCI_SUCCESS) {
264                 dev_warn(&ihost->pdev->dev,
265                          "%s: scic_task_request_construct failed - "
266                          "status = 0x%x\n",
267                          __func__,
268                          status);
269                 return NULL;
270         }
271
272         /* XXX convert to get this from task->tproto like other drivers */
273         if (dev->dev_type == SAS_END_DEV) {
274                 isci_tmf->proto = SAS_PROTOCOL_SSP;
275                 status = scic_task_request_construct_ssp(ireq);
276                 if (status != SCI_SUCCESS)
277                         return NULL;
278         }
279
280         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
281                 isci_tmf->proto = SAS_PROTOCOL_SATA;
282                 status = isci_sata_management_task_request_build(ireq);
283
284                 if (status != SCI_SUCCESS)
285                         return NULL;
286         }
287         return ireq;
288 }
289
290 int isci_task_execute_tmf(struct isci_host *ihost,
291                           struct isci_remote_device *isci_device,
292                           struct isci_tmf *tmf, unsigned long timeout_ms)
293 {
294         DECLARE_COMPLETION_ONSTACK(completion);
295         enum sci_task_status status = SCI_TASK_FAILURE;
296         struct scic_sds_remote_device *sci_device;
297         struct isci_request *ireq;
298         int ret = TMF_RESP_FUNC_FAILED;
299         unsigned long flags;
300         unsigned long timeleft;
301         u16 tag;
302
303         spin_lock_irqsave(&ihost->scic_lock, flags);
304         tag = isci_alloc_tag(ihost);
305         spin_unlock_irqrestore(&ihost->scic_lock, flags);
306
307         if (tag == SCI_CONTROLLER_INVALID_IO_TAG)
308                 return ret;
309
310         /* sanity check, return TMF_RESP_FUNC_FAILED
311          * if the device is not there and ready.
312          */
313         if (!isci_device ||
314             (!test_bit(IDEV_IO_READY, &isci_device->flags) &&
315              !test_bit(IDEV_IO_NCQERROR, &isci_device->flags))) {
316                 dev_dbg(&ihost->pdev->dev,
317                         "%s: isci_device = %p not ready (%#lx)\n",
318                         __func__,
319                         isci_device, isci_device ? isci_device->flags : 0);
320                 goto err_tci;
321         } else
322                 dev_dbg(&ihost->pdev->dev,
323                         "%s: isci_device = %p\n",
324                         __func__, isci_device);
325
326         sci_device = &isci_device->sci;
327
328         /* Assign the pointer to the TMF's completion kernel wait structure. */
329         tmf->complete = &completion;
330
331         ireq = isci_task_request_build(ihost, isci_device, tag, tmf);
332         if (!ireq)
333                 goto err_tci;
334
335         spin_lock_irqsave(&ihost->scic_lock, flags);
336
337         /* start the TMF io. */
338         status = scic_controller_start_task(&ihost->sci,
339                                             sci_device,
340                                             ireq);
341
342         if (status != SCI_TASK_SUCCESS) {
343                 dev_warn(&ihost->pdev->dev,
344                          "%s: start_io failed - status = 0x%x, request = %p\n",
345                          __func__,
346                          status,
347                          ireq);
348                 spin_unlock_irqrestore(&ihost->scic_lock, flags);
349                 goto err_tci;
350         }
351
352         if (tmf->cb_state_func != NULL)
353                 tmf->cb_state_func(isci_tmf_started, tmf, tmf->cb_data);
354
355         isci_request_change_state(ireq, started);
356
357         /* add the request to the remote device request list. */
358         list_add(&ireq->dev_node, &isci_device->reqs_in_process);
359
360         spin_unlock_irqrestore(&ihost->scic_lock, flags);
361
362         /* Wait for the TMF to complete, or a timeout. */
363         timeleft = wait_for_completion_timeout(&completion,
364                                                msecs_to_jiffies(timeout_ms));
365
366         if (timeleft == 0) {
367                 spin_lock_irqsave(&ihost->scic_lock, flags);
368
369                 if (tmf->cb_state_func != NULL)
370                         tmf->cb_state_func(isci_tmf_timed_out, tmf, tmf->cb_data);
371
372                 scic_controller_terminate_request(&ihost->sci,
373                                                   &isci_device->sci,
374                                                   ireq);
375
376                 spin_unlock_irqrestore(&ihost->scic_lock, flags);
377
378                 wait_for_completion(tmf->complete);
379         }
380
381         isci_print_tmf(tmf);
382
383         if (tmf->status == SCI_SUCCESS)
384                 ret =  TMF_RESP_FUNC_COMPLETE;
385         else if (tmf->status == SCI_FAILURE_IO_RESPONSE_VALID) {
386                 dev_dbg(&ihost->pdev->dev,
387                         "%s: tmf.status == "
388                         "SCI_FAILURE_IO_RESPONSE_VALID\n",
389                         __func__);
390                 ret =  TMF_RESP_FUNC_COMPLETE;
391         }
392         /* Else - leave the default "failed" status alone. */
393
394         dev_dbg(&ihost->pdev->dev,
395                 "%s: completed request = %p\n",
396                 __func__,
397                 ireq);
398
399         return ret;
400
401  err_tci:
402         spin_lock_irqsave(&ihost->scic_lock, flags);
403         isci_tci_free(ihost, ISCI_TAG_TCI(tag));
404         spin_unlock_irqrestore(&ihost->scic_lock, flags);
405
406         return ret;
407 }
408
409 void isci_task_build_tmf(
410         struct isci_tmf *tmf,
411         enum isci_tmf_function_codes code,
412         void (*tmf_sent_cb)(enum isci_tmf_cb_state,
413                             struct isci_tmf *,
414                             void *),
415         void *cb_data)
416 {
417         memset(tmf, 0, sizeof(*tmf));
418
419         tmf->tmf_code      = code;
420         tmf->cb_state_func = tmf_sent_cb;
421         tmf->cb_data       = cb_data;
422 }
423
424 static void isci_task_build_abort_task_tmf(
425         struct isci_tmf *tmf,
426         enum isci_tmf_function_codes code,
427         void (*tmf_sent_cb)(enum isci_tmf_cb_state,
428                             struct isci_tmf *,
429                             void *),
430         struct isci_request *old_request)
431 {
432         isci_task_build_tmf(tmf, code, tmf_sent_cb,
433                             (void *)old_request);
434         tmf->io_tag = old_request->io_tag;
435 }
436
437 /**
438  * isci_task_validate_request_to_abort() - This function checks the given I/O
439  *    against the "started" state.  If the request is still "started", it's
440  *    state is changed to aborted. NOTE: isci_host->scic_lock MUST BE HELD
441  *    BEFORE CALLING THIS FUNCTION.
442  * @isci_request: This parameter specifies the request object to control.
443  * @isci_host: This parameter specifies the ISCI host object
444  * @isci_device: This is the device to which the request is pending.
445  * @aborted_io_completion: This is a completion structure that will be added to
446  *    the request in case it is changed to aborting; this completion is
447  *    triggered when the request is fully completed.
448  *
449  * Either "started" on successful change of the task status to "aborted", or
450  * "unallocated" if the task cannot be controlled.
451  */
452 static enum isci_request_status isci_task_validate_request_to_abort(
453         struct isci_request *isci_request,
454         struct isci_host *isci_host,
455         struct isci_remote_device *isci_device,
456         struct completion *aborted_io_completion)
457 {
458         enum isci_request_status old_state = unallocated;
459
460         /* Only abort the task if it's in the
461          *  device's request_in_process list
462          */
463         if (isci_request && !list_empty(&isci_request->dev_node)) {
464                 old_state = isci_request_change_started_to_aborted(
465                         isci_request, aborted_io_completion);
466
467         }
468
469         return old_state;
470 }
471
472 /**
473 * isci_request_cleanup_completed_loiterer() - This function will take care of
474 *    the final cleanup on any request which has been explicitly terminated.
475 * @isci_host: This parameter specifies the ISCI host object
476 * @isci_device: This is the device to which the request is pending.
477 * @isci_request: This parameter specifies the terminated request object.
478 * @task: This parameter is the libsas I/O request.
479 */
480 static void isci_request_cleanup_completed_loiterer(
481         struct isci_host          *isci_host,
482         struct isci_remote_device *isci_device,
483         struct isci_request       *isci_request,
484         struct sas_task           *task)
485 {
486         unsigned long flags;
487
488         dev_dbg(&isci_host->pdev->dev,
489                 "%s: isci_device=%p, request=%p, task=%p\n",
490                 __func__, isci_device, isci_request, task);
491
492         if (task != NULL) {
493
494                 spin_lock_irqsave(&task->task_state_lock, flags);
495                 task->lldd_task = NULL;
496
497                 task->task_state_flags &= ~SAS_TASK_NEED_DEV_RESET;
498
499                 isci_set_task_doneflags(task);
500
501                 /* If this task is not in the abort path, call task_done. */
502                 if (!(task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
503
504                         spin_unlock_irqrestore(&task->task_state_lock, flags);
505                         task->task_done(task);
506                 } else
507                         spin_unlock_irqrestore(&task->task_state_lock, flags);
508         }
509
510         if (isci_request != NULL) {
511                 spin_lock_irqsave(&isci_host->scic_lock, flags);
512                 list_del_init(&isci_request->dev_node);
513                 spin_unlock_irqrestore(&isci_host->scic_lock, flags);
514         }
515 }
516
517 /**
518  * isci_terminate_request_core() - This function will terminate the given
519  *    request, and wait for it to complete.  This function must only be called
520  *    from a thread that can wait.  Note that the request is terminated and
521  *    completed (back to the host, if started there).
522  * @isci_host: This SCU.
523  * @isci_device: The target.
524  * @isci_request: The I/O request to be terminated.
525  *
526  */
527 static void isci_terminate_request_core(
528         struct isci_host *isci_host,
529         struct isci_remote_device *isci_device,
530         struct isci_request *isci_request)
531 {
532         enum sci_status status      = SCI_SUCCESS;
533         bool was_terminated         = false;
534         bool needs_cleanup_handling = false;
535         enum isci_request_status request_status;
536         unsigned long     flags;
537         unsigned long     termination_completed = 1;
538         struct completion *io_request_completion;
539         struct sas_task   *task;
540
541         dev_dbg(&isci_host->pdev->dev,
542                 "%s: device = %p; request = %p\n",
543                 __func__, isci_device, isci_request);
544
545         spin_lock_irqsave(&isci_host->scic_lock, flags);
546
547         io_request_completion = isci_request->io_request_completion;
548
549         task = (isci_request->ttype == io_task)
550                 ? isci_request_access_task(isci_request)
551                 : NULL;
552
553         /* Note that we are not going to control
554          * the target to abort the request.
555          */
556         set_bit(IREQ_COMPLETE_IN_TARGET, &isci_request->flags);
557
558         /* Make sure the request wasn't just sitting around signalling
559          * device condition (if the request handle is NULL, then the
560          * request completed but needed additional handling here).
561          */
562         if (!test_bit(IREQ_TERMINATED, &isci_request->flags)) {
563                 was_terminated = true;
564                 needs_cleanup_handling = true;
565                 status = scic_controller_terminate_request(
566                         &isci_host->sci,
567                         &isci_device->sci,
568                         isci_request);
569         }
570         spin_unlock_irqrestore(&isci_host->scic_lock, flags);
571
572         /*
573          * The only time the request to terminate will
574          * fail is when the io request is completed and
575          * being aborted.
576          */
577         if (status != SCI_SUCCESS) {
578                 dev_err(&isci_host->pdev->dev,
579                         "%s: scic_controller_terminate_request"
580                         " returned = 0x%x\n",
581                         __func__, status);
582
583                 isci_request->io_request_completion = NULL;
584
585         } else {
586                 if (was_terminated) {
587                         dev_dbg(&isci_host->pdev->dev,
588                                 "%s: before completion wait (%p/%p)\n",
589                                 __func__, isci_request, io_request_completion);
590
591                         /* Wait here for the request to complete. */
592                         #define TERMINATION_TIMEOUT_MSEC 500
593                         termination_completed
594                                 = wait_for_completion_timeout(
595                                    io_request_completion,
596                                    msecs_to_jiffies(TERMINATION_TIMEOUT_MSEC));
597
598                         if (!termination_completed) {
599
600                                 /* The request to terminate has timed out.  */
601                                 spin_lock_irqsave(&isci_host->scic_lock,
602                                                   flags);
603
604                                 /* Check for state changes. */
605                                 if (!test_bit(IREQ_TERMINATED, &isci_request->flags)) {
606
607                                         /* The best we can do is to have the
608                                          * request die a silent death if it
609                                          * ever really completes.
610                                          *
611                                          * Set the request state to "dead",
612                                          * and clear the task pointer so that
613                                          * an actual completion event callback
614                                          * doesn't do anything.
615                                          */
616                                         isci_request->status = dead;
617                                         isci_request->io_request_completion
618                                                 = NULL;
619
620                                         if (isci_request->ttype == io_task) {
621
622                                                 /* Break links with the
623                                                 * sas_task.
624                                                 */
625                                                 isci_request->ttype_ptr.io_task_ptr
626                                                         = NULL;
627                                         }
628                                 } else
629                                         termination_completed = 1;
630
631                                 spin_unlock_irqrestore(&isci_host->scic_lock,
632                                                        flags);
633
634                                 if (!termination_completed) {
635
636                                         dev_err(&isci_host->pdev->dev,
637                                                 "%s: *** Timeout waiting for "
638                                                 "termination(%p/%p)\n",
639                                                 __func__, io_request_completion,
640                                                 isci_request);
641
642                                         /* The request can no longer be referenced
643                                          * safely since it may go away if the
644                                          * termination every really does complete.
645                                          */
646                                         isci_request = NULL;
647                                 }
648                         }
649                         if (termination_completed)
650                                 dev_dbg(&isci_host->pdev->dev,
651                                         "%s: after completion wait (%p/%p)\n",
652                                         __func__, isci_request, io_request_completion);
653                 }
654
655                 if (termination_completed) {
656
657                         isci_request->io_request_completion = NULL;
658
659                         /* Peek at the status of the request.  This will tell
660                          * us if there was special handling on the request such that it
661                          * needs to be detached and freed here.
662                          */
663                         spin_lock_irqsave(&isci_request->state_lock, flags);
664                         request_status = isci_request_get_state(isci_request);
665
666                         if ((isci_request->ttype == io_task) /* TMFs are in their own thread */
667                             && ((request_status == aborted)
668                                 || (request_status == aborting)
669                                 || (request_status == terminating)
670                                 || (request_status == completed)
671                                 || (request_status == dead)
672                                 )
673                             ) {
674
675                                 /* The completion routine won't free a request in
676                                  * the aborted/aborting/etc. states, so we do
677                                  * it here.
678                                  */
679                                 needs_cleanup_handling = true;
680                         }
681                         spin_unlock_irqrestore(&isci_request->state_lock, flags);
682
683                 }
684                 if (needs_cleanup_handling)
685                         isci_request_cleanup_completed_loiterer(
686                                 isci_host, isci_device, isci_request, task);
687         }
688 }
689
690 /**
691  * isci_terminate_pending_requests() - This function will change the all of the
692  *    requests on the given device's state to "aborting", will terminate the
693  *    requests, and wait for them to complete.  This function must only be
694  *    called from a thread that can wait.  Note that the requests are all
695  *    terminated and completed (back to the host, if started there).
696  * @isci_host: This parameter specifies SCU.
697  * @isci_device: This parameter specifies the target.
698  *
699  */
700 void isci_terminate_pending_requests(struct isci_host *ihost,
701                                      struct isci_remote_device *idev)
702 {
703         struct completion request_completion;
704         enum isci_request_status old_state;
705         unsigned long flags;
706         LIST_HEAD(list);
707
708         spin_lock_irqsave(&ihost->scic_lock, flags);
709         list_splice_init(&idev->reqs_in_process, &list);
710
711         /* assumes that isci_terminate_request_core deletes from the list */
712         while (!list_empty(&list)) {
713                 struct isci_request *ireq = list_entry(list.next, typeof(*ireq), dev_node);
714
715                 /* Change state to "terminating" if it is currently
716                  * "started".
717                  */
718                 old_state = isci_request_change_started_to_newstate(ireq,
719                                                                     &request_completion,
720                                                                     terminating);
721                 switch (old_state) {
722                 case started:
723                 case completed:
724                 case aborting:
725                         break;
726                 default:
727                         /* termination in progress, or otherwise dispositioned.
728                          * We know the request was on 'list' so should be safe
729                          * to move it back to reqs_in_process
730                          */
731                         list_move(&ireq->dev_node, &idev->reqs_in_process);
732                         ireq = NULL;
733                         break;
734                 }
735
736                 if (!ireq)
737                         continue;
738                 spin_unlock_irqrestore(&ihost->scic_lock, flags);
739
740                 init_completion(&request_completion);
741
742                 dev_dbg(&ihost->pdev->dev,
743                          "%s: idev=%p request=%p; task=%p old_state=%d\n",
744                          __func__, idev, ireq,
745                         ireq->ttype == io_task ? isci_request_access_task(ireq) : NULL,
746                         old_state);
747
748                 /* If the old_state is started:
749                  * This request was not already being aborted. If it had been,
750                  * then the aborting I/O (ie. the TMF request) would not be in
751                  * the aborting state, and thus would be terminated here.  Note
752                  * that since the TMF completion's call to the kernel function
753                  * "complete()" does not happen until the pending I/O request
754                  * terminate fully completes, we do not have to implement a
755                  * special wait here for already aborting requests - the
756                  * termination of the TMF request will force the request
757                  * to finish it's already started terminate.
758                  *
759                  * If old_state == completed:
760                  * This request completed from the SCU hardware perspective
761                  * and now just needs cleaning up in terms of freeing the
762                  * request and potentially calling up to libsas.
763                  *
764                  * If old_state == aborting:
765                  * This request has already gone through a TMF timeout, but may
766                  * not have been terminated; needs cleaning up at least.
767                  */
768                 isci_terminate_request_core(ihost, idev, ireq);
769                 spin_lock_irqsave(&ihost->scic_lock, flags);
770         }
771         spin_unlock_irqrestore(&ihost->scic_lock, flags);
772 }
773
774 /**
775  * isci_task_send_lu_reset_sas() - This function is called by of the SAS Domain
776  *    Template functions.
777  * @lun: This parameter specifies the lun to be reset.
778  *
779  * status, zero indicates success.
780  */
781 static int isci_task_send_lu_reset_sas(
782         struct isci_host *isci_host,
783         struct isci_remote_device *isci_device,
784         u8 *lun)
785 {
786         struct isci_tmf tmf;
787         int ret = TMF_RESP_FUNC_FAILED;
788
789         dev_dbg(&isci_host->pdev->dev,
790                 "%s: isci_host = %p, isci_device = %p\n",
791                 __func__, isci_host, isci_device);
792         /* Send the LUN reset to the target.  By the time the call returns,
793          * the TMF has fully exected in the target (in which case the return
794          * value is "TMF_RESP_FUNC_COMPLETE", or the request timed-out (or
795          * was otherwise unable to be executed ("TMF_RESP_FUNC_FAILED").
796          */
797         isci_task_build_tmf(&tmf, isci_tmf_ssp_lun_reset, NULL, NULL);
798
799         #define ISCI_LU_RESET_TIMEOUT_MS 2000 /* 2 second timeout. */
800         ret = isci_task_execute_tmf(isci_host, isci_device, &tmf, ISCI_LU_RESET_TIMEOUT_MS);
801
802         if (ret == TMF_RESP_FUNC_COMPLETE)
803                 dev_dbg(&isci_host->pdev->dev,
804                         "%s: %p: TMF_LU_RESET passed\n",
805                         __func__, isci_device);
806         else
807                 dev_dbg(&isci_host->pdev->dev,
808                         "%s: %p: TMF_LU_RESET failed (%x)\n",
809                         __func__, isci_device, ret);
810
811         return ret;
812 }
813
814 /**
815  * isci_task_lu_reset() - This function is one of the SAS Domain Template
816  *    functions. This is one of the Task Management functoins called by libsas,
817  *    to reset the given lun. Note the assumption that while this call is
818  *    executing, no I/O will be sent by the host to the device.
819  * @lun: This parameter specifies the lun to be reset.
820  *
821  * status, zero indicates success.
822  */
823 int isci_task_lu_reset(struct domain_device *domain_device, u8 *lun)
824 {
825         struct isci_host *isci_host = dev_to_ihost(domain_device);
826         struct isci_remote_device *isci_device;
827         unsigned long flags;
828         int ret;
829
830         spin_lock_irqsave(&isci_host->scic_lock, flags);
831         isci_device = isci_lookup_device(domain_device);
832         spin_unlock_irqrestore(&isci_host->scic_lock, flags);
833
834         dev_dbg(&isci_host->pdev->dev,
835                 "%s: domain_device=%p, isci_host=%p; isci_device=%p\n",
836                  __func__, domain_device, isci_host, isci_device);
837
838         if (isci_device)
839                 set_bit(IDEV_EH, &isci_device->flags);
840
841         /* If there is a device reset pending on any request in the
842          * device's list, fail this LUN reset request in order to
843          * escalate to the device reset.
844          */
845         if (!isci_device ||
846             isci_device_is_reset_pending(isci_host, isci_device)) {
847                 dev_warn(&isci_host->pdev->dev,
848                          "%s: No dev (%p), or "
849                          "RESET PENDING: domain_device=%p\n",
850                          __func__, isci_device, domain_device);
851                 ret = TMF_RESP_FUNC_FAILED;
852                 goto out;
853         }
854
855         /* Send the task management part of the reset. */
856         if (sas_protocol_ata(domain_device->tproto)) {
857                 ret = isci_task_send_lu_reset_sata(isci_host, isci_device, lun);
858         } else
859                 ret = isci_task_send_lu_reset_sas(isci_host, isci_device, lun);
860
861         /* If the LUN reset worked, all the I/O can now be terminated. */
862         if (ret == TMF_RESP_FUNC_COMPLETE)
863                 /* Terminate all I/O now. */
864                 isci_terminate_pending_requests(isci_host,
865                                                 isci_device);
866
867  out:
868         isci_put_device(isci_device);
869         return ret;
870 }
871
872
873 /*       int (*lldd_clear_nexus_port)(struct asd_sas_port *); */
874 int isci_task_clear_nexus_port(struct asd_sas_port *port)
875 {
876         return TMF_RESP_FUNC_FAILED;
877 }
878
879
880
881 int isci_task_clear_nexus_ha(struct sas_ha_struct *ha)
882 {
883         return TMF_RESP_FUNC_FAILED;
884 }
885
886 /* Task Management Functions. Must be called from process context.       */
887
888 /**
889  * isci_abort_task_process_cb() - This is a helper function for the abort task
890  *    TMF command.  It manages the request state with respect to the successful
891  *    transmission / completion of the abort task request.
892  * @cb_state: This parameter specifies when this function was called - after
893  *    the TMF request has been started and after it has timed-out.
894  * @tmf: This parameter specifies the TMF in progress.
895  *
896  *
897  */
898 static void isci_abort_task_process_cb(
899         enum isci_tmf_cb_state cb_state,
900         struct isci_tmf *tmf,
901         void *cb_data)
902 {
903         struct isci_request *old_request;
904
905         old_request = (struct isci_request *)cb_data;
906
907         dev_dbg(&old_request->isci_host->pdev->dev,
908                 "%s: tmf=%p, old_request=%p\n",
909                 __func__, tmf, old_request);
910
911         switch (cb_state) {
912
913         case isci_tmf_started:
914                 /* The TMF has been started.  Nothing to do here, since the
915                  * request state was already set to "aborted" by the abort
916                  * task function.
917                  */
918                 if ((old_request->status != aborted)
919                         && (old_request->status != completed))
920                         dev_err(&old_request->isci_host->pdev->dev,
921                                 "%s: Bad request status (%d): tmf=%p, old_request=%p\n",
922                                 __func__, old_request->status, tmf, old_request);
923                 break;
924
925         case isci_tmf_timed_out:
926
927                 /* Set the task's state to "aborting", since the abort task
928                  * function thread set it to "aborted" (above) in anticipation
929                  * of the task management request working correctly.  Since the
930                  * timeout has now fired, the TMF request failed.  We set the
931                  * state such that the request completion will indicate the
932                  * device is no longer present.
933                  */
934                 isci_request_change_state(old_request, aborting);
935                 break;
936
937         default:
938                 dev_err(&old_request->isci_host->pdev->dev,
939                         "%s: Bad cb_state (%d): tmf=%p, old_request=%p\n",
940                         __func__, cb_state, tmf, old_request);
941                 break;
942         }
943 }
944
945 /**
946  * isci_task_abort_task() - This function is one of the SAS Domain Template
947  *    functions. This function is called by libsas to abort a specified task.
948  * @task: This parameter specifies the SAS task to abort.
949  *
950  * status, zero indicates success.
951  */
952 int isci_task_abort_task(struct sas_task *task)
953 {
954         struct isci_host *isci_host = dev_to_ihost(task->dev);
955         DECLARE_COMPLETION_ONSTACK(aborted_io_completion);
956         struct isci_request       *old_request = NULL;
957         enum isci_request_status  old_state;
958         struct isci_remote_device *isci_device = NULL;
959         struct isci_tmf           tmf;
960         int                       ret = TMF_RESP_FUNC_FAILED;
961         unsigned long             flags;
962         bool                      any_dev_reset = false;
963
964         /* Get the isci_request reference from the task.  Note that
965          * this check does not depend on the pending request list
966          * in the device, because tasks driving resets may land here
967          * after completion in the core.
968          */
969         spin_lock_irqsave(&isci_host->scic_lock, flags);
970         spin_lock(&task->task_state_lock);
971
972         old_request = task->lldd_task;
973
974         /* If task is already done, the request isn't valid */
975         if (!(task->task_state_flags & SAS_TASK_STATE_DONE) &&
976             (task->task_state_flags & SAS_TASK_AT_INITIATOR) &&
977             old_request)
978                 isci_device = isci_lookup_device(task->dev);
979
980         spin_unlock(&task->task_state_lock);
981         spin_unlock_irqrestore(&isci_host->scic_lock, flags);
982
983         dev_dbg(&isci_host->pdev->dev,
984                 "%s: task = %p\n", __func__, task);
985
986         if (!isci_device || !old_request)
987                 goto out;
988
989         set_bit(IDEV_EH, &isci_device->flags);
990
991         /* This version of the driver will fail abort requests for
992          * SATA/STP.  Failing the abort request this way will cause the
993          * SCSI error handler thread to escalate to LUN reset
994          */
995         if (sas_protocol_ata(task->task_proto)) {
996                 dev_warn(&isci_host->pdev->dev,
997                             " task %p is for a STP/SATA device;"
998                             " returning TMF_RESP_FUNC_FAILED\n"
999                             " to cause a LUN reset...\n", task);
1000                 goto out;
1001         }
1002
1003         dev_dbg(&isci_host->pdev->dev,
1004                 "%s: old_request == %p\n", __func__, old_request);
1005
1006         any_dev_reset = isci_device_is_reset_pending(isci_host,isci_device);
1007
1008         spin_lock_irqsave(&task->task_state_lock, flags);
1009
1010         any_dev_reset = any_dev_reset || (task->task_state_flags & SAS_TASK_NEED_DEV_RESET);
1011
1012         /* If the extraction of the request reference from the task
1013          * failed, then the request has been completed (or if there is a
1014          * pending reset then this abort request function must be failed
1015          * in order to escalate to the target reset).
1016          */
1017         if ((old_request == NULL) || any_dev_reset) {
1018
1019                 /* If the device reset task flag is set, fail the task
1020                  * management request.  Otherwise, the original request
1021                  * has completed.
1022                  */
1023                 if (any_dev_reset) {
1024
1025                         /* Turn off the task's DONE to make sure this
1026                          * task is escalated to a target reset.
1027                          */
1028                         task->task_state_flags &= ~SAS_TASK_STATE_DONE;
1029
1030                         /* Make the reset happen as soon as possible. */
1031                         task->task_state_flags |= SAS_TASK_NEED_DEV_RESET;
1032
1033                         spin_unlock_irqrestore(&task->task_state_lock, flags);
1034
1035                         /* Fail the task management request in order to
1036                          * escalate to the target reset.
1037                          */
1038                         ret = TMF_RESP_FUNC_FAILED;
1039
1040                         dev_dbg(&isci_host->pdev->dev,
1041                                 "%s: Failing task abort in order to "
1042                                 "escalate to target reset because\n"
1043                                 "SAS_TASK_NEED_DEV_RESET is set for "
1044                                 "task %p on dev %p\n",
1045                                 __func__, task, isci_device);
1046
1047
1048                 } else {
1049                         /* The request has already completed and there
1050                          * is nothing to do here other than to set the task
1051                          * done bit, and indicate that the task abort function
1052                          * was sucessful.
1053                          */
1054                         isci_set_task_doneflags(task);
1055
1056                         spin_unlock_irqrestore(&task->task_state_lock, flags);
1057
1058                         ret = TMF_RESP_FUNC_COMPLETE;
1059
1060                         dev_dbg(&isci_host->pdev->dev,
1061                                 "%s: abort task not needed for %p\n",
1062                                 __func__, task);
1063                 }
1064                 goto out;
1065         }
1066         else
1067                 spin_unlock_irqrestore(&task->task_state_lock, flags);
1068
1069         spin_lock_irqsave(&isci_host->scic_lock, flags);
1070
1071         /* Check the request status and change to "aborted" if currently
1072          * "starting"; if true then set the I/O kernel completion
1073          * struct that will be triggered when the request completes.
1074          */
1075         old_state = isci_task_validate_request_to_abort(
1076                                 old_request, isci_host, isci_device,
1077                                 &aborted_io_completion);
1078         if ((old_state != started) &&
1079             (old_state != completed) &&
1080             (old_state != aborting)) {
1081
1082                 spin_unlock_irqrestore(&isci_host->scic_lock, flags);
1083
1084                 /* The request was already being handled by someone else (because
1085                 * they got to set the state away from started).
1086                 */
1087                 dev_dbg(&isci_host->pdev->dev,
1088                         "%s:  device = %p; old_request %p already being aborted\n",
1089                         __func__,
1090                         isci_device, old_request);
1091                 ret = TMF_RESP_FUNC_COMPLETE;
1092                 goto out;
1093         }
1094         if (task->task_proto == SAS_PROTOCOL_SMP ||
1095             test_bit(IREQ_COMPLETE_IN_TARGET, &old_request->flags)) {
1096
1097                 spin_unlock_irqrestore(&isci_host->scic_lock, flags);
1098
1099                 dev_dbg(&isci_host->pdev->dev,
1100                         "%s: SMP request (%d)"
1101                         " or complete_in_target (%d), thus no TMF\n",
1102                         __func__, (task->task_proto == SAS_PROTOCOL_SMP),
1103                         test_bit(IREQ_COMPLETE_IN_TARGET, &old_request->flags));
1104
1105                 /* Set the state on the task. */
1106                 isci_task_all_done(task);
1107
1108                 ret = TMF_RESP_FUNC_COMPLETE;
1109
1110                 /* Stopping and SMP devices are not sent a TMF, and are not
1111                  * reset, but the outstanding I/O request is terminated below.
1112                  */
1113         } else {
1114                 /* Fill in the tmf stucture */
1115                 isci_task_build_abort_task_tmf(&tmf, isci_tmf_ssp_task_abort,
1116                                                isci_abort_task_process_cb,
1117                                                old_request);
1118
1119                 spin_unlock_irqrestore(&isci_host->scic_lock, flags);
1120
1121                 #define ISCI_ABORT_TASK_TIMEOUT_MS 500 /* half second timeout. */
1122                 ret = isci_task_execute_tmf(isci_host, isci_device, &tmf,
1123                                             ISCI_ABORT_TASK_TIMEOUT_MS);
1124
1125                 if (ret != TMF_RESP_FUNC_COMPLETE)
1126                         dev_err(&isci_host->pdev->dev,
1127                                 "%s: isci_task_send_tmf failed\n",
1128                                 __func__);
1129         }
1130         if (ret == TMF_RESP_FUNC_COMPLETE) {
1131                 set_bit(IREQ_COMPLETE_IN_TARGET, &old_request->flags);
1132
1133                 /* Clean up the request on our side, and wait for the aborted
1134                  * I/O to complete.
1135                  */
1136                 isci_terminate_request_core(isci_host, isci_device, old_request);
1137         }
1138
1139         /* Make sure we do not leave a reference to aborted_io_completion */
1140         old_request->io_request_completion = NULL;
1141  out:
1142         isci_put_device(isci_device);
1143         return ret;
1144 }
1145
1146 /**
1147  * isci_task_abort_task_set() - This function is one of the SAS Domain Template
1148  *    functions. This is one of the Task Management functoins called by libsas,
1149  *    to abort all task for the given lun.
1150  * @d_device: This parameter specifies the domain device associated with this
1151  *    request.
1152  * @lun: This parameter specifies the lun associated with this request.
1153  *
1154  * status, zero indicates success.
1155  */
1156 int isci_task_abort_task_set(
1157         struct domain_device *d_device,
1158         u8 *lun)
1159 {
1160         return TMF_RESP_FUNC_FAILED;
1161 }
1162
1163
1164 /**
1165  * isci_task_clear_aca() - This function is one of the SAS Domain Template
1166  *    functions. This is one of the Task Management functoins called by libsas.
1167  * @d_device: This parameter specifies the domain device associated with this
1168  *    request.
1169  * @lun: This parameter specifies the lun        associated with this request.
1170  *
1171  * status, zero indicates success.
1172  */
1173 int isci_task_clear_aca(
1174         struct domain_device *d_device,
1175         u8 *lun)
1176 {
1177         return TMF_RESP_FUNC_FAILED;
1178 }
1179
1180
1181
1182 /**
1183  * isci_task_clear_task_set() - This function is one of the SAS Domain Template
1184  *    functions. This is one of the Task Management functoins called by libsas.
1185  * @d_device: This parameter specifies the domain device associated with this
1186  *    request.
1187  * @lun: This parameter specifies the lun        associated with this request.
1188  *
1189  * status, zero indicates success.
1190  */
1191 int isci_task_clear_task_set(
1192         struct domain_device *d_device,
1193         u8 *lun)
1194 {
1195         return TMF_RESP_FUNC_FAILED;
1196 }
1197
1198
1199 /**
1200  * isci_task_query_task() - This function is implemented to cause libsas to
1201  *    correctly escalate the failed abort to a LUN or target reset (this is
1202  *    because sas_scsi_find_task libsas function does not correctly interpret
1203  *    all return codes from the abort task call).  When TMF_RESP_FUNC_SUCC is
1204  *    returned, libsas turns this into a LUN reset; when FUNC_FAILED is
1205  *    returned, libsas will turn this into a target reset
1206  * @task: This parameter specifies the sas task being queried.
1207  * @lun: This parameter specifies the lun associated with this request.
1208  *
1209  * status, zero indicates success.
1210  */
1211 int isci_task_query_task(
1212         struct sas_task *task)
1213 {
1214         /* See if there is a pending device reset for this device. */
1215         if (task->task_state_flags & SAS_TASK_NEED_DEV_RESET)
1216                 return TMF_RESP_FUNC_FAILED;
1217         else
1218                 return TMF_RESP_FUNC_SUCC;
1219 }
1220
1221 /*
1222  * isci_task_request_complete() - This function is called by the sci core when
1223  *    an task request completes.
1224  * @ihost: This parameter specifies the ISCI host object
1225  * @ireq: This parameter is the completed isci_request object.
1226  * @completion_status: This parameter specifies the completion status from the
1227  *    sci core.
1228  *
1229  * none.
1230  */
1231 void
1232 isci_task_request_complete(struct isci_host *ihost,
1233                            struct isci_request *ireq,
1234                            enum sci_task_status completion_status)
1235 {
1236         struct isci_tmf *tmf = isci_request_access_tmf(ireq);
1237         struct completion *tmf_complete;
1238
1239         dev_dbg(&ihost->pdev->dev,
1240                 "%s: request = %p, status=%d\n",
1241                 __func__, ireq, completion_status);
1242
1243         isci_request_change_state(ireq, completed);
1244
1245         tmf->status = completion_status;
1246         set_bit(IREQ_COMPLETE_IN_TARGET, &ireq->flags);
1247
1248         if (tmf->proto == SAS_PROTOCOL_SSP) {
1249                 memcpy(&tmf->resp.resp_iu,
1250                        &ireq->ssp.rsp,
1251                        SSP_RESP_IU_MAX_SIZE);
1252         } else if (tmf->proto == SAS_PROTOCOL_SATA) {
1253                 memcpy(&tmf->resp.d2h_fis,
1254                        &ireq->stp.rsp,
1255                        sizeof(struct dev_to_host_fis));
1256         }
1257
1258         /* PRINT_TMF( ((struct isci_tmf *)request->task)); */
1259         tmf_complete = tmf->complete;
1260
1261         scic_controller_complete_io(&ihost->sci, ireq->target_device, ireq);
1262         /* set the 'terminated' flag handle to make sure it cannot be terminated
1263          *  or completed again.
1264          */
1265         set_bit(IREQ_TERMINATED, &ireq->flags);
1266
1267         isci_request_change_state(ireq, unallocated);
1268         list_del_init(&ireq->dev_node);
1269
1270         /* The task management part completes last. */
1271         complete(tmf_complete);
1272 }
1273
1274 static void isci_smp_task_timedout(unsigned long _task)
1275 {
1276         struct sas_task *task = (void *) _task;
1277         unsigned long flags;
1278
1279         spin_lock_irqsave(&task->task_state_lock, flags);
1280         if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
1281                 task->task_state_flags |= SAS_TASK_STATE_ABORTED;
1282         spin_unlock_irqrestore(&task->task_state_lock, flags);
1283
1284         complete(&task->completion);
1285 }
1286
1287 static void isci_smp_task_done(struct sas_task *task)
1288 {
1289         if (!del_timer(&task->timer))
1290                 return;
1291         complete(&task->completion);
1292 }
1293
1294 static struct sas_task *isci_alloc_task(void)
1295 {
1296         struct sas_task *task = kzalloc(sizeof(*task), GFP_KERNEL);
1297
1298         if (task) {
1299                 INIT_LIST_HEAD(&task->list);
1300                 spin_lock_init(&task->task_state_lock);
1301                 task->task_state_flags = SAS_TASK_STATE_PENDING;
1302                 init_timer(&task->timer);
1303                 init_completion(&task->completion);
1304         }
1305
1306         return task;
1307 }
1308
1309 static void isci_free_task(struct isci_host *ihost, struct sas_task  *task)
1310 {
1311         if (task) {
1312                 BUG_ON(!list_empty(&task->list));
1313                 kfree(task);
1314         }
1315 }
1316
1317 static int isci_smp_execute_task(struct isci_host *ihost,
1318                                  struct domain_device *dev, void *req,
1319                                  int req_size, void *resp, int resp_size)
1320 {
1321         int res, retry;
1322         struct sas_task *task = NULL;
1323
1324         for (retry = 0; retry < 3; retry++) {
1325                 task = isci_alloc_task();
1326                 if (!task)
1327                         return -ENOMEM;
1328
1329                 task->dev = dev;
1330                 task->task_proto = dev->tproto;
1331                 sg_init_one(&task->smp_task.smp_req, req, req_size);
1332                 sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
1333
1334                 task->task_done = isci_smp_task_done;
1335
1336                 task->timer.data = (unsigned long) task;
1337                 task->timer.function = isci_smp_task_timedout;
1338                 task->timer.expires = jiffies + 10*HZ;
1339                 add_timer(&task->timer);
1340
1341                 res = isci_task_execute_task(task, 1, GFP_KERNEL);
1342
1343                 if (res) {
1344                         del_timer(&task->timer);
1345                         dev_err(&ihost->pdev->dev,
1346                                 "%s: executing SMP task failed:%d\n",
1347                                 __func__, res);
1348                         goto ex_err;
1349                 }
1350
1351                 wait_for_completion(&task->completion);
1352                 res = -ECOMM;
1353                 if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
1354                         dev_err(&ihost->pdev->dev,
1355                                 "%s: smp task timed out or aborted\n",
1356                                 __func__);
1357                         isci_task_abort_task(task);
1358                         if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
1359                                 dev_err(&ihost->pdev->dev,
1360                                         "%s: SMP task aborted and not done\n",
1361                                         __func__);
1362                                 goto ex_err;
1363                         }
1364                 }
1365                 if (task->task_status.resp == SAS_TASK_COMPLETE &&
1366                     task->task_status.stat == SAM_STAT_GOOD) {
1367                         res = 0;
1368                         break;
1369                 }
1370                 if (task->task_status.resp == SAS_TASK_COMPLETE &&
1371                       task->task_status.stat == SAS_DATA_UNDERRUN) {
1372                         /* no error, but return the number of bytes of
1373                         * underrun */
1374                         res = task->task_status.residual;
1375                         break;
1376                 }
1377                 if (task->task_status.resp == SAS_TASK_COMPLETE &&
1378                       task->task_status.stat == SAS_DATA_OVERRUN) {
1379                         res = -EMSGSIZE;
1380                         break;
1381                 } else {
1382                         dev_err(&ihost->pdev->dev,
1383                                 "%s: task to dev %016llx response: 0x%x "
1384                                 "status 0x%x\n", __func__,
1385                                 SAS_ADDR(dev->sas_addr),
1386                                 task->task_status.resp,
1387                                 task->task_status.stat);
1388                         isci_free_task(ihost, task);
1389                         task = NULL;
1390                 }
1391         }
1392 ex_err:
1393         BUG_ON(retry == 3 && task != NULL);
1394         isci_free_task(ihost, task);
1395         return res;
1396 }
1397
1398 #define DISCOVER_REQ_SIZE  16
1399 #define DISCOVER_RESP_SIZE 56
1400
1401 int isci_smp_get_phy_attached_dev_type(struct isci_host *ihost,
1402                                        struct domain_device *dev,
1403                                        int phy_id, int *adt)
1404 {
1405         struct smp_resp *disc_resp;
1406         u8 *disc_req;
1407         int res;
1408
1409         disc_resp = kzalloc(DISCOVER_RESP_SIZE, GFP_KERNEL);
1410         if (!disc_resp)
1411                 return -ENOMEM;
1412
1413         disc_req = kzalloc(DISCOVER_REQ_SIZE, GFP_KERNEL);
1414         if (disc_req) {
1415                 disc_req[0] = SMP_REQUEST;
1416                 disc_req[1] = SMP_DISCOVER;
1417                 disc_req[9] = phy_id;
1418         } else {
1419                 kfree(disc_resp);
1420                 return -ENOMEM;
1421         }
1422         res = isci_smp_execute_task(ihost, dev, disc_req, DISCOVER_REQ_SIZE,
1423                                     disc_resp, DISCOVER_RESP_SIZE);
1424         if (!res) {
1425                 if (disc_resp->result != SMP_RESP_FUNC_ACC)
1426                         res = disc_resp->result;
1427                 else
1428                         *adt = disc_resp->disc.attached_dev_type;
1429         }
1430         kfree(disc_req);
1431         kfree(disc_resp);
1432
1433         return res;
1434 }
1435
1436 static void isci_wait_for_smp_phy_reset(struct isci_remote_device *idev, int phy_num)
1437 {
1438         struct domain_device *dev = idev->domain_dev;
1439         struct isci_port *iport = idev->isci_port;
1440         struct isci_host *ihost = iport->isci_host;
1441         int res, iteration = 0, attached_device_type;
1442         #define STP_WAIT_MSECS 25000
1443         unsigned long tmo = msecs_to_jiffies(STP_WAIT_MSECS);
1444         unsigned long deadline = jiffies + tmo;
1445         enum {
1446                 SMP_PHYWAIT_PHYDOWN,
1447                 SMP_PHYWAIT_PHYUP,
1448                 SMP_PHYWAIT_DONE
1449         } phy_state = SMP_PHYWAIT_PHYDOWN;
1450
1451         /* While there is time, wait for the phy to go away and come back */
1452         while (time_is_after_jiffies(deadline) && phy_state != SMP_PHYWAIT_DONE) {
1453                 int event = atomic_read(&iport->event);
1454
1455                 ++iteration;
1456
1457                 tmo = wait_event_timeout(ihost->eventq,
1458                                          event != atomic_read(&iport->event) ||
1459                                          !test_bit(IPORT_BCN_BLOCKED, &iport->flags),
1460                                          tmo);
1461                 /* link down, stop polling */
1462                 if (!test_bit(IPORT_BCN_BLOCKED, &iport->flags))
1463                         break;
1464
1465                 dev_dbg(&ihost->pdev->dev,
1466                         "%s: iport %p, iteration %d,"
1467                         " phase %d: time_remaining %lu, bcns = %d\n",
1468                         __func__, iport, iteration, phy_state,
1469                         tmo, test_bit(IPORT_BCN_PENDING, &iport->flags));
1470
1471                 res = isci_smp_get_phy_attached_dev_type(ihost, dev, phy_num,
1472                                                          &attached_device_type);
1473                 tmo = deadline - jiffies;
1474
1475                 if (res) {
1476                         dev_warn(&ihost->pdev->dev,
1477                                  "%s: iteration %d, phase %d:"
1478                                  " SMP error=%d, time_remaining=%lu\n",
1479                                  __func__, iteration, phy_state, res, tmo);
1480                         break;
1481                 }
1482                 dev_dbg(&ihost->pdev->dev,
1483                         "%s: iport %p, iteration %d,"
1484                         " phase %d: time_remaining %lu, bcns = %d, "
1485                         "attdevtype = %x\n",
1486                         __func__, iport, iteration, phy_state,
1487                         tmo, test_bit(IPORT_BCN_PENDING, &iport->flags),
1488                         attached_device_type);
1489
1490                 switch (phy_state) {
1491                 case SMP_PHYWAIT_PHYDOWN:
1492                         /* Has the device gone away? */
1493                         if (!attached_device_type)
1494                                 phy_state = SMP_PHYWAIT_PHYUP;
1495
1496                         break;
1497
1498                 case SMP_PHYWAIT_PHYUP:
1499                         /* Has the device come back? */
1500                         if (attached_device_type)
1501                                 phy_state = SMP_PHYWAIT_DONE;
1502                         break;
1503
1504                 case SMP_PHYWAIT_DONE:
1505                         break;
1506                 }
1507
1508         }
1509         dev_dbg(&ihost->pdev->dev, "%s: done\n",  __func__);
1510 }
1511
1512 static int isci_reset_device(struct isci_host *ihost,
1513                              struct isci_remote_device *idev, int hard_reset)
1514 {
1515         struct sas_phy *phy = sas_find_local_phy(idev->domain_dev);
1516         struct isci_port *iport = idev->isci_port;
1517         enum sci_status status;
1518         unsigned long flags;
1519         int rc;
1520
1521         dev_dbg(&ihost->pdev->dev, "%s: idev %p\n", __func__, idev);
1522
1523         spin_lock_irqsave(&ihost->scic_lock, flags);
1524         status = scic_remote_device_reset(&idev->sci);
1525         if (status != SCI_SUCCESS) {
1526                 spin_unlock_irqrestore(&ihost->scic_lock, flags);
1527
1528                 dev_warn(&ihost->pdev->dev,
1529                          "%s: scic_remote_device_reset(%p) returned %d!\n",
1530                          __func__, idev, status);
1531
1532                 return TMF_RESP_FUNC_FAILED;
1533         }
1534         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1535
1536         /* Make sure all pending requests are able to be fully terminated. */
1537         isci_device_clear_reset_pending(ihost, idev);
1538
1539         /* If this is a device on an expander, disable BCN processing. */
1540         if (!scsi_is_sas_phy_local(phy))
1541                 set_bit(IPORT_BCN_BLOCKED, &iport->flags);
1542
1543         rc = sas_phy_reset(phy, hard_reset);
1544
1545         /* Terminate in-progress I/O now. */
1546         isci_remote_device_nuke_requests(ihost, idev);
1547
1548         /* Since all pending TCs have been cleaned, resume the RNC. */
1549         spin_lock_irqsave(&ihost->scic_lock, flags);
1550         status = scic_remote_device_reset_complete(&idev->sci);
1551         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1552
1553         /* If this is a device on an expander, bring the phy back up. */
1554         if (!scsi_is_sas_phy_local(phy)) {
1555                 /* A phy reset will cause the device to go away then reappear.
1556                  * Since libsas will take action on incoming BCNs (eg. remove
1557                  * a device going through an SMP phy-control driven reset),
1558                  * we need to wait until the phy comes back up before letting
1559                  * discovery proceed in libsas.
1560                  */
1561                 isci_wait_for_smp_phy_reset(idev, phy->number);
1562
1563                 spin_lock_irqsave(&ihost->scic_lock, flags);
1564                 isci_port_bcn_enable(ihost, idev->isci_port);
1565                 spin_unlock_irqrestore(&ihost->scic_lock, flags);
1566         }
1567
1568         if (status != SCI_SUCCESS) {
1569                 dev_warn(&ihost->pdev->dev,
1570                          "%s: scic_remote_device_reset_complete(%p) "
1571                          "returned %d!\n", __func__, idev, status);
1572         }
1573
1574         dev_dbg(&ihost->pdev->dev, "%s: idev %p complete.\n", __func__, idev);
1575
1576         return rc;
1577 }
1578
1579 int isci_task_I_T_nexus_reset(struct domain_device *dev)
1580 {
1581         struct isci_host *ihost = dev_to_ihost(dev);
1582         struct isci_remote_device *idev;
1583         int ret, hard_reset = 1;
1584         unsigned long flags;
1585
1586         spin_lock_irqsave(&ihost->scic_lock, flags);
1587         idev = isci_lookup_device(dev);
1588         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1589
1590         if (!idev || !test_bit(IDEV_EH, &idev->flags)) {
1591                 ret = TMF_RESP_FUNC_COMPLETE;
1592                 goto out;
1593         }
1594
1595         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP))
1596                 hard_reset = 0;
1597
1598         ret = isci_reset_device(ihost, idev, hard_reset);
1599  out:
1600         isci_put_device(idev);
1601         return ret;
1602 }
1603
1604 int isci_bus_reset_handler(struct scsi_cmnd *cmd)
1605 {
1606         struct domain_device *dev = sdev_to_domain_dev(cmd->device);
1607         struct isci_host *ihost = dev_to_ihost(dev);
1608         struct isci_remote_device *idev;
1609         int ret, hard_reset = 1;
1610         unsigned long flags;
1611
1612         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP))
1613                 hard_reset = 0;
1614
1615         spin_lock_irqsave(&ihost->scic_lock, flags);
1616         idev = isci_lookup_device(dev);
1617         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1618
1619         if (!idev) {
1620                 ret = TMF_RESP_FUNC_COMPLETE;
1621                 goto out;
1622         }
1623
1624         ret = isci_reset_device(ihost, idev, hard_reset);
1625  out:
1626         isci_put_device(idev);
1627         return ret;
1628 }