drivers/scsi/isci/remote_device.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 #include <scsi/sas.h>
  56 #include "isci.h"
  57 #include "port.h"
  58 #include "remote_device.h"
  59 #include "request.h"
  60 #include "remote_node_context.h"
  61 #include "scu_event_codes.h"
  62 #include "task.h"
  63
  64 /**
  65  * isci_remote_device_not_ready() - This function is called by the scic when
  66  *    the remote device is not ready. We mark the isci device as ready (not
  67  *    "ready_for_io") and signal the waiting proccess.
  68  * @isci_host: This parameter specifies the isci host object.
  69  * @isci_device: This parameter specifies the remote device
  70  *
  71  * scic_lock is held on entrance to this function.
  72  */
  73 static void isci_remote_device_not_ready(struct isci_host *ihost,
  74                                   struct isci_remote_device *idev, u32 reason)
  75 {
  76         struct isci_request * ireq;
  77
  78         dev_dbg(&ihost->pdev->dev,
  79                 "%s: isci_device = %p\n", __func__, idev);
  80
  81         switch (reason) {
  82         case SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED:
  83                 set_bit(IDEV_GONE, &idev->flags);
  84                 break;
  85         case SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED:
  86                 set_bit(IDEV_IO_NCQERROR, &idev->flags);
  87
  88                 /* Kill all outstanding requests for the device. */
  89                 list_for_each_entry(ireq, &idev->reqs_in_process, dev_node) {
  90
  91                         dev_dbg(&ihost->pdev->dev,
  92                                 "%s: isci_device = %p request = %p\n",
  93                                 __func__, idev, ireq);
  94
  95                         scic_controller_terminate_request(&ihost->sci,
  96                                                           idev,
  97                                                           ireq);
  98                 }
  99                 /* Fall through into the default case... */
 100         default:
 101                 clear_bit(IDEV_IO_READY, &idev->flags);
 102                 break;
 103         }
 104 }
 105
 106 /**
 107  * isci_remote_device_ready() - This function is called by the scic when the
 108  *    remote device is ready. We mark the isci device as ready and signal the
 109  *    waiting proccess.
 110  * @ihost: our valid isci_host
 111  * @idev: remote device
 112  *
 113  */
 114 static void isci_remote_device_ready(struct isci_host *ihost, struct isci_remote_device *idev)
 115 {
 116         dev_dbg(&ihost->pdev->dev,
 117                 "%s: idev = %p\n", __func__, idev);
 118
 119         clear_bit(IDEV_IO_NCQERROR, &idev->flags);
 120         set_bit(IDEV_IO_READY, &idev->flags);
 121         if (test_and_clear_bit(IDEV_START_PENDING, &idev->flags))
 122                 wake_up(&ihost->eventq);
 123 }
 124
 125 /* called once the remote node context is ready to be freed.
 126  * The remote device can now report that its stop operation is complete. none
 127  */
 128 static void rnc_destruct_done(void *_dev)
 129 {
 130         struct isci_remote_device *idev = _dev;
 131
 132         BUG_ON(idev->started_request_count != 0);
 133         sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 134 }
 135
 136 static enum sci_status scic_sds_remote_device_terminate_requests(struct isci_remote_device *idev)
 137 {
 138         struct scic_sds_controller *scic = idev->owning_port->owning_controller;
 139         struct isci_host *ihost = scic_to_ihost(scic);
 140         enum sci_status status  = SCI_SUCCESS;
 141         u32 i;
 142
 143         for (i = 0; i < SCI_MAX_IO_REQUESTS; i++) {
 144                 struct isci_request *ireq = ihost->reqs[i];
 145                 enum sci_status s;
 146
 147                 if (!test_bit(IREQ_ACTIVE, &ireq->flags) ||
 148                     ireq->target_device != idev)
 149                         continue;
 150
 151                 s = scic_controller_terminate_request(scic, idev, ireq);
 152                 if (s != SCI_SUCCESS)
 153                         status = s;
 154         }
 155
 156         return status;
 157 }
 158
 159 enum sci_status scic_remote_device_stop(struct isci_remote_device *idev,
 160                                         u32 timeout)
 161 {
 162         struct sci_base_state_machine *sm = &idev->sm;
 163         enum scic_sds_remote_device_states state = sm->current_state_id;
 164
 165         switch (state) {
 166         case SCI_DEV_INITIAL:
 167         case SCI_DEV_FAILED:
 168         case SCI_DEV_FINAL:
 169         default:
 170                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 171                          __func__, state);
 172                 return SCI_FAILURE_INVALID_STATE;
 173         case SCI_DEV_STOPPED:
 174                 return SCI_SUCCESS;
 175         case SCI_DEV_STARTING:
 176                 /* device not started so there had better be no requests */
 177                 BUG_ON(idev->started_request_count != 0);
 178                 scic_sds_remote_node_context_destruct(&idev->rnc,
 179                                                       rnc_destruct_done, idev);
 180                 /* Transition to the stopping state and wait for the
 181                  * remote node to complete being posted and invalidated.
 182                  */
 183                 sci_change_state(sm, SCI_DEV_STOPPING);
 184                 return SCI_SUCCESS;
 185         case SCI_DEV_READY:
 186         case SCI_STP_DEV_IDLE:
 187         case SCI_STP_DEV_CMD:
 188         case SCI_STP_DEV_NCQ:
 189         case SCI_STP_DEV_NCQ_ERROR:
 190         case SCI_STP_DEV_AWAIT_RESET:
 191         case SCI_SMP_DEV_IDLE:
 192         case SCI_SMP_DEV_CMD:
 193                 sci_change_state(sm, SCI_DEV_STOPPING);
 194                 if (idev->started_request_count == 0) {
 195                         scic_sds_remote_node_context_destruct(&idev->rnc,
 196                                                               rnc_destruct_done, idev);
 197                         return SCI_SUCCESS;
 198                 } else
 199                         return scic_sds_remote_device_terminate_requests(idev);
 200                 break;
 201         case SCI_DEV_STOPPING:
 202                 /* All requests should have been terminated, but if there is an
 203                  * attempt to stop a device already in the stopping state, then
 204                  * try again to terminate.
 205                  */
 206                 return scic_sds_remote_device_terminate_requests(idev);
 207         case SCI_DEV_RESETTING:
 208                 sci_change_state(sm, SCI_DEV_STOPPING);
 209                 return SCI_SUCCESS;
 210         }
 211 }
 212
 213 enum sci_status scic_remote_device_reset(struct isci_remote_device *idev)
 214 {
 215         struct sci_base_state_machine *sm = &idev->sm;
 216         enum scic_sds_remote_device_states state = sm->current_state_id;
 217
 218         switch (state) {
 219         case SCI_DEV_INITIAL:
 220         case SCI_DEV_STOPPED:
 221         case SCI_DEV_STARTING:
 222         case SCI_SMP_DEV_IDLE:
 223         case SCI_SMP_DEV_CMD:
 224         case SCI_DEV_STOPPING:
 225         case SCI_DEV_FAILED:
 226         case SCI_DEV_RESETTING:
 227         case SCI_DEV_FINAL:
 228         default:
 229                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 230                          __func__, state);
 231                 return SCI_FAILURE_INVALID_STATE;
 232         case SCI_DEV_READY:
 233         case SCI_STP_DEV_IDLE:
 234         case SCI_STP_DEV_CMD:
 235         case SCI_STP_DEV_NCQ:
 236         case SCI_STP_DEV_NCQ_ERROR:
 237         case SCI_STP_DEV_AWAIT_RESET:
 238                 sci_change_state(sm, SCI_DEV_RESETTING);
 239                 return SCI_SUCCESS;
 240         }
 241 }
 242
 243 enum sci_status scic_remote_device_reset_complete(struct isci_remote_device *idev)
 244 {
 245         struct sci_base_state_machine *sm = &idev->sm;
 246         enum scic_sds_remote_device_states state = sm->current_state_id;
 247
 248         if (state != SCI_DEV_RESETTING) {
 249                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 250                          __func__, state);
 251                 return SCI_FAILURE_INVALID_STATE;
 252         }
 253
 254         sci_change_state(sm, SCI_DEV_READY);
 255         return SCI_SUCCESS;
 256 }
 257
 258 enum sci_status scic_sds_remote_device_suspend(struct isci_remote_device *idev,
 259                                                u32 suspend_type)
 260 {
 261         struct sci_base_state_machine *sm = &idev->sm;
 262         enum scic_sds_remote_device_states state = sm->current_state_id;
 263
 264         if (state != SCI_STP_DEV_CMD) {
 265                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 266                          __func__, state);
 267                 return SCI_FAILURE_INVALID_STATE;
 268         }
 269
 270         return scic_sds_remote_node_context_suspend(&idev->rnc,
 271                                                     suspend_type, NULL, NULL);
 272 }
 273
 274 enum sci_status scic_sds_remote_device_frame_handler(struct isci_remote_device *idev,
 275                                                      u32 frame_index)
 276 {
 277         struct sci_base_state_machine *sm = &idev->sm;
 278         enum scic_sds_remote_device_states state = sm->current_state_id;
 279         struct scic_sds_controller *scic = idev->owning_port->owning_controller;
 280         enum sci_status status;
 281
 282         switch (state) {
 283         case SCI_DEV_INITIAL:
 284         case SCI_DEV_STOPPED:
 285         case SCI_DEV_STARTING:
 286         case SCI_STP_DEV_IDLE:
 287         case SCI_SMP_DEV_IDLE:
 288         case SCI_DEV_FINAL:
 289         default:
 290                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 291                          __func__, state);
 292                 /* Return the frame back to the controller */
 293                 scic_sds_controller_release_frame(scic, frame_index);
 294                 return SCI_FAILURE_INVALID_STATE;
 295         case SCI_DEV_READY:
 296         case SCI_STP_DEV_NCQ_ERROR:
 297         case SCI_STP_DEV_AWAIT_RESET:
 298         case SCI_DEV_STOPPING:
 299         case SCI_DEV_FAILED:
 300         case SCI_DEV_RESETTING: {
 301                 struct isci_request *ireq;
 302                 struct ssp_frame_hdr hdr;
 303                 void *frame_header;
 304                 ssize_t word_cnt;
 305
 306                 status = scic_sds_unsolicited_frame_control_get_header(&scic->uf_control,
 307                                                                        frame_index,
 308                                                                        &frame_header);
 309                 if (status != SCI_SUCCESS)
 310                         return status;
 311
 312                 word_cnt = sizeof(hdr) / sizeof(u32);
 313                 sci_swab32_cpy(&hdr, frame_header, word_cnt);
 314
 315                 ireq = scic_request_by_tag(scic, be16_to_cpu(hdr.tag));
 316                 if (ireq && ireq->target_device == idev) {
 317                         /* The IO request is now in charge of releasing the frame */
 318                         status = scic_sds_io_request_frame_handler(ireq, frame_index);
 319                 } else {
 320                         /* We could not map this tag to a valid IO
 321                          * request Just toss the frame and continue
 322                          */
 323                         scic_sds_controller_release_frame(scic, frame_index);
 324                 }
 325                 break;
 326         }
 327         case SCI_STP_DEV_NCQ: {
 328                 struct dev_to_host_fis *hdr;
 329
 330                 status = scic_sds_unsolicited_frame_control_get_header(&scic->uf_control,
 331                                                                        frame_index,
 332                                                                        (void **)&hdr);
 333                 if (status != SCI_SUCCESS)
 334                         return status;
 335
 336                 if (hdr->fis_type == FIS_SETDEVBITS &&
 337                     (hdr->status & ATA_ERR)) {
 338                         idev->not_ready_reason = SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED;
 339
 340                         /* TODO Check sactive and complete associated IO if any. */
 341                         sci_change_state(sm, SCI_STP_DEV_NCQ_ERROR);
 342                 } else if (hdr->fis_type == FIS_REGD2H &&
 343                            (hdr->status & ATA_ERR)) {
 344                         /*
 345                          * Some devices return D2H FIS when an NCQ error is detected.
 346                          * Treat this like an SDB error FIS ready reason.
 347                          */
 348                         idev->not_ready_reason = SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED;
 349                         sci_change_state(&idev->sm, SCI_STP_DEV_NCQ_ERROR);
 350                 } else
 351                         status = SCI_FAILURE;
 352
 353                 scic_sds_controller_release_frame(scic, frame_index);
 354                 break;
 355         }
 356         case SCI_STP_DEV_CMD:
 357         case SCI_SMP_DEV_CMD:
 358                 /* The device does not process any UF received from the hardware while
 359                  * in this state.  All unsolicited frames are forwarded to the io request
 360                  * object.
 361                  */
 362                 status = scic_sds_io_request_frame_handler(idev->working_request, frame_index);
 363                 break;
 364         }
 365
 366         return status;
 367 }
 368
 369 static bool is_remote_device_ready(struct isci_remote_device *idev)
 370 {
 371
 372         struct sci_base_state_machine *sm = &idev->sm;
 373         enum scic_sds_remote_device_states state = sm->current_state_id;
 374
 375         switch (state) {
 376         case SCI_DEV_READY:
 377         case SCI_STP_DEV_IDLE:
 378         case SCI_STP_DEV_CMD:
 379         case SCI_STP_DEV_NCQ:
 380         case SCI_STP_DEV_NCQ_ERROR:
 381         case SCI_STP_DEV_AWAIT_RESET:
 382         case SCI_SMP_DEV_IDLE:
 383         case SCI_SMP_DEV_CMD:
 384                 return true;
 385         default:
 386                 return false;
 387         }
 388 }
 389
 390 enum sci_status scic_sds_remote_device_event_handler(struct isci_remote_device *idev,
 391                                                      u32 event_code)
 392 {
 393         struct sci_base_state_machine *sm = &idev->sm;
 394         enum scic_sds_remote_device_states state = sm->current_state_id;
 395         enum sci_status status;
 396
 397         switch (scu_get_event_type(event_code)) {
 398         case SCU_EVENT_TYPE_RNC_OPS_MISC:
 399         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 400         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 401                 status = scic_sds_remote_node_context_event_handler(&idev->rnc, event_code);
 402                 break;
 403         case SCU_EVENT_TYPE_PTX_SCHEDULE_EVENT:
 404                 if (scu_get_event_code(event_code) == SCU_EVENT_IT_NEXUS_TIMEOUT) {
 405                         status = SCI_SUCCESS;
 406
 407                         /* Suspend the associated RNC */
 408                         scic_sds_remote_node_context_suspend(&idev->rnc,
 409                                                               SCI_SOFTWARE_SUSPENSION,
 410                                                               NULL, NULL);
 411
 412                         dev_dbg(scirdev_to_dev(idev),
 413                                 "%s: device: %p event code: %x: %s\n",
 414                                 __func__, idev, event_code,
 415                                 is_remote_device_ready(idev)
 416                                 ? "I_T_Nexus_Timeout event"
 417                                 : "I_T_Nexus_Timeout event in wrong state");
 418
 419                         break;
 420                 }
 421         /* Else, fall through and treat as unhandled... */
 422         default:
 423                 dev_dbg(scirdev_to_dev(idev),
 424                         "%s: device: %p event code: %x: %s\n",
 425                         __func__, idev, event_code,
 426                         is_remote_device_ready(idev)
 427                         ? "unexpected event"
 428                         : "unexpected event in wrong state");
 429                 status = SCI_FAILURE_INVALID_STATE;
 430                 break;
 431         }
 432
 433         if (status != SCI_SUCCESS)
 434                 return status;
 435
 436         if (state == SCI_STP_DEV_IDLE) {
 437
 438                 /* We pick up suspension events to handle specifically to this
 439                  * state. We resume the RNC right away.
 440                  */
 441                 if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
 442                     scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX)
 443                         status = scic_sds_remote_node_context_resume(&idev->rnc, NULL, NULL);
 444         }
 445
 446         return status;
 447 }
 448
 449 static void scic_sds_remote_device_start_request(struct isci_remote_device *idev,
 450                                                  struct isci_request *ireq,
 451                                                  enum sci_status status)
 452 {
 453         struct isci_port *iport = idev->owning_port;
 454
 455         /* cleanup requests that failed after starting on the port */
 456         if (status != SCI_SUCCESS)
 457                 scic_sds_port_complete_io(iport, idev, ireq);
 458         else {
 459                 kref_get(&idev->kref);
 460                 scic_sds_remote_device_increment_request_count(idev);
 461         }
 462 }
 463
 464 enum sci_status scic_sds_remote_device_start_io(struct scic_sds_controller *scic,
 465                                                 struct isci_remote_device *idev,
 466                                                 struct isci_request *ireq)
 467 {
 468         struct sci_base_state_machine *sm = &idev->sm;
 469         enum scic_sds_remote_device_states state = sm->current_state_id;
 470         struct isci_port *iport = idev->owning_port;
 471         enum sci_status status;
 472
 473         switch (state) {
 474         case SCI_DEV_INITIAL:
 475         case SCI_DEV_STOPPED:
 476         case SCI_DEV_STARTING:
 477         case SCI_STP_DEV_NCQ_ERROR:
 478         case SCI_DEV_STOPPING:
 479         case SCI_DEV_FAILED:
 480         case SCI_DEV_RESETTING:
 481         case SCI_DEV_FINAL:
 482         default:
 483                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 484                          __func__, state);
 485                 return SCI_FAILURE_INVALID_STATE;
 486         case SCI_DEV_READY:
 487                 /* attempt to start an io request for this device object. The remote
 488                  * device object will issue the start request for the io and if
 489                  * successful it will start the request for the port object then
 490                  * increment its own request count.
 491                  */
 492                 status = scic_sds_port_start_io(iport, idev, ireq);
 493                 if (status != SCI_SUCCESS)
 494                         return status;
 495
 496                 status = scic_sds_remote_node_context_start_io(&idev->rnc, ireq);
 497                 if (status != SCI_SUCCESS)
 498                         break;
 499
 500                 status = scic_sds_request_start(ireq);
 501                 break;
 502         case SCI_STP_DEV_IDLE: {
 503                 /* handle the start io operation for a sata device that is in
 504                  * the command idle state. - Evalute the type of IO request to
 505                  * be started - If its an NCQ request change to NCQ substate -
 506                  * If its any other command change to the CMD substate
 507                  *
 508                  * If this is a softreset we may want to have a different
 509                  * substate.
 510                  */
 511                 enum scic_sds_remote_device_states new_state;
 512                 struct sas_task *task = isci_request_access_task(ireq);
 513
 514                 status = scic_sds_port_start_io(iport, idev, ireq);
 515                 if (status != SCI_SUCCESS)
 516                         return status;
 517
 518                 status = scic_sds_remote_node_context_start_io(&idev->rnc, ireq);
 519                 if (status != SCI_SUCCESS)
 520                         break;
 521
 522                 status = scic_sds_request_start(ireq);
 523                 if (status != SCI_SUCCESS)
 524                         break;
 525
 526                 if (task->ata_task.use_ncq)
 527                         new_state = SCI_STP_DEV_NCQ;
 528                 else {
 529                         idev->working_request = ireq;
 530                         new_state = SCI_STP_DEV_CMD;
 531                 }
 532                 sci_change_state(sm, new_state);
 533                 break;
 534         }
 535         case SCI_STP_DEV_NCQ: {
 536                 struct sas_task *task = isci_request_access_task(ireq);
 537
 538                 if (task->ata_task.use_ncq) {
 539                         status = scic_sds_port_start_io(iport, idev, ireq);
 540                         if (status != SCI_SUCCESS)
 541                                 return status;
 542
 543                         status = scic_sds_remote_node_context_start_io(&idev->rnc, ireq);
 544                         if (status != SCI_SUCCESS)
 545                                 break;
 546
 547                         status = scic_sds_request_start(ireq);
 548                 } else
 549                         return SCI_FAILURE_INVALID_STATE;
 550                 break;
 551         }
 552         case SCI_STP_DEV_AWAIT_RESET:
 553                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 554         case SCI_SMP_DEV_IDLE:
 555                 status = scic_sds_port_start_io(iport, idev, ireq);
 556                 if (status != SCI_SUCCESS)
 557                         return status;
 558
 559                 status = scic_sds_remote_node_context_start_io(&idev->rnc, ireq);
 560                 if (status != SCI_SUCCESS)
 561                         break;
 562
 563                 status = scic_sds_request_start(ireq);
 564                 if (status != SCI_SUCCESS)
 565                         break;
 566
 567                 idev->working_request = ireq;
 568                 sci_change_state(&idev->sm, SCI_SMP_DEV_CMD);
 569                 break;
 570         case SCI_STP_DEV_CMD:
 571         case SCI_SMP_DEV_CMD:
 572                 /* device is already handling a command it can not accept new commands
 573                  * until this one is complete.
 574                  */
 575                 return SCI_FAILURE_INVALID_STATE;
 576         }
 577
 578         scic_sds_remote_device_start_request(idev, ireq, status);
 579         return status;
 580 }
 581
 582 static enum sci_status common_complete_io(struct isci_port *iport,
 583                                           struct isci_remote_device *idev,
 584                                           struct isci_request *ireq)
 585 {
 586         enum sci_status status;
 587
 588         status = scic_sds_request_complete(ireq);
 589         if (status != SCI_SUCCESS)
 590                 return status;
 591
 592         status = scic_sds_port_complete_io(iport, idev, ireq);
 593         if (status != SCI_SUCCESS)
 594                 return status;
 595
 596         scic_sds_remote_device_decrement_request_count(idev);
 597         return status;
 598 }
 599
 600 enum sci_status scic_sds_remote_device_complete_io(struct scic_sds_controller *scic,
 601                                                    struct isci_remote_device *idev,
 602                                                    struct isci_request *ireq)
 603 {
 604         struct sci_base_state_machine *sm = &idev->sm;
 605         enum scic_sds_remote_device_states state = sm->current_state_id;
 606         struct isci_port *iport = idev->owning_port;
 607         enum sci_status status;
 608
 609         switch (state) {
 610         case SCI_DEV_INITIAL:
 611         case SCI_DEV_STOPPED:
 612         case SCI_DEV_STARTING:
 613         case SCI_STP_DEV_IDLE:
 614         case SCI_SMP_DEV_IDLE:
 615         case SCI_DEV_FAILED:
 616         case SCI_DEV_FINAL:
 617         default:
 618                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 619                          __func__, state);
 620                 return SCI_FAILURE_INVALID_STATE;
 621         case SCI_DEV_READY:
 622         case SCI_STP_DEV_AWAIT_RESET:
 623         case SCI_DEV_RESETTING:
 624                 status = common_complete_io(iport, idev, ireq);
 625                 break;
 626         case SCI_STP_DEV_CMD:
 627         case SCI_STP_DEV_NCQ:
 628         case SCI_STP_DEV_NCQ_ERROR:
 629                 status = common_complete_io(iport, idev, ireq);
 630                 if (status != SCI_SUCCESS)
 631                         break;
 632
 633                 if (ireq->sci_status == SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) {
 634                         /* This request causes hardware error, device needs to be Lun Reset.
 635                          * So here we force the state machine to IDLE state so the rest IOs
 636                          * can reach RNC state handler, these IOs will be completed by RNC with
 637                          * status of "DEVICE_RESET_REQUIRED", instead of "INVALID STATE".
 638                          */
 639                         sci_change_state(sm, SCI_STP_DEV_AWAIT_RESET);
 640                 } else if (scic_sds_remote_device_get_request_count(idev) == 0)
 641                         sci_change_state(sm, SCI_STP_DEV_IDLE);
 642                 break;
 643         case SCI_SMP_DEV_CMD:
 644                 status = common_complete_io(iport, idev, ireq);
 645                 if (status != SCI_SUCCESS)
 646                         break;
 647                 sci_change_state(sm, SCI_SMP_DEV_IDLE);
 648                 break;
 649         case SCI_DEV_STOPPING:
 650                 status = common_complete_io(iport, idev, ireq);
 651                 if (status != SCI_SUCCESS)
 652                         break;
 653
 654                 if (scic_sds_remote_device_get_request_count(idev) == 0)
 655                         scic_sds_remote_node_context_destruct(&idev->rnc,
 656                                                               rnc_destruct_done,
 657                                                               idev);
 658                 break;
 659         }
 660
 661         if (status != SCI_SUCCESS)
 662                 dev_err(scirdev_to_dev(idev),
 663                         "%s: Port:0x%p Device:0x%p Request:0x%p Status:0x%x "
 664                         "could not complete\n", __func__, iport,
 665                         idev, ireq, status);
 666         else
 667                 isci_put_device(idev);
 668
 669         return status;
 670 }
 671
 672 static void scic_sds_remote_device_continue_request(void *dev)
 673 {
 674         struct isci_remote_device *idev = dev;
 675
 676         /* we need to check if this request is still valid to continue. */
 677         if (idev->working_request)
 678                 scic_controller_continue_io(idev->working_request);
 679 }
 680
 681 enum sci_status scic_sds_remote_device_start_task(struct scic_sds_controller *scic,
 682                                                   struct isci_remote_device *idev,
 683                                                   struct isci_request *ireq)
 684 {
 685         struct sci_base_state_machine *sm = &idev->sm;
 686         enum scic_sds_remote_device_states state = sm->current_state_id;
 687         struct isci_port *iport = idev->owning_port;
 688         enum sci_status status;
 689
 690         switch (state) {
 691         case SCI_DEV_INITIAL:
 692         case SCI_DEV_STOPPED:
 693         case SCI_DEV_STARTING:
 694         case SCI_SMP_DEV_IDLE:
 695         case SCI_SMP_DEV_CMD:
 696         case SCI_DEV_STOPPING:
 697         case SCI_DEV_FAILED:
 698         case SCI_DEV_RESETTING:
 699         case SCI_DEV_FINAL:
 700         default:
 701                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 702                          __func__, state);
 703                 return SCI_FAILURE_INVALID_STATE;
 704         case SCI_STP_DEV_IDLE:
 705         case SCI_STP_DEV_CMD:
 706         case SCI_STP_DEV_NCQ:
 707         case SCI_STP_DEV_NCQ_ERROR:
 708         case SCI_STP_DEV_AWAIT_RESET:
 709                 status = scic_sds_port_start_io(iport, idev, ireq);
 710                 if (status != SCI_SUCCESS)
 711                         return status;
 712
 713                 status = scic_sds_remote_node_context_start_task(&idev->rnc, ireq);
 714                 if (status != SCI_SUCCESS)
 715                         goto out;
 716
 717                 status = scic_sds_request_start(ireq);
 718                 if (status != SCI_SUCCESS)
 719                         goto out;
 720
 721                 /* Note: If the remote device state is not IDLE this will
 722                  * replace the request that probably resulted in the task
 723                  * management request.
 724                  */
 725                 idev->working_request = ireq;
 726                 sci_change_state(sm, SCI_STP_DEV_CMD);
 727
 728                 /* The remote node context must cleanup the TCi to NCQ mapping
 729                  * table.  The only way to do this correctly is to either write
 730                  * to the TLCR register or to invalidate and repost the RNC. In
 731                  * either case the remote node context state machine will take
 732                  * the correct action when the remote node context is suspended
 733                  * and later resumed.
 734                  */
 735                 scic_sds_remote_node_context_suspend(&idev->rnc,
 736                                 SCI_SOFTWARE_SUSPENSION, NULL, NULL);
 737                 scic_sds_remote_node_context_resume(&idev->rnc,
 738                                 scic_sds_remote_device_continue_request,
 739                                                     idev);
 740
 741         out:
 742                 scic_sds_remote_device_start_request(idev, ireq, status);
 743                 /* We need to let the controller start request handler know that
 744                  * it can't post TC yet. We will provide a callback function to
 745                  * post TC when RNC gets resumed.
 746                  */
 747                 return SCI_FAILURE_RESET_DEVICE_PARTIAL_SUCCESS;
 748         case SCI_DEV_READY:
 749                 status = scic_sds_port_start_io(iport, idev, ireq);
 750                 if (status != SCI_SUCCESS)
 751                         return status;
 752
 753                 status = scic_sds_remote_node_context_start_task(&idev->rnc, ireq);
 754                 if (status != SCI_SUCCESS)
 755                         break;
 756
 757                 status = scic_sds_request_start(ireq);
 758                 break;
 759         }
 760         scic_sds_remote_device_start_request(idev, ireq, status);
 761
 762         return status;
 763 }
 764
 765 /**
 766  *
 767  * @sci_dev:
 768  * @request:
 769  *
 770  * This method takes the request and bulids an appropriate SCU context for the
 771  * request and then requests the controller to post the request. none
 772  */
 773 void scic_sds_remote_device_post_request(
 774         struct isci_remote_device *idev,
 775         u32 request)
 776 {
 777         u32 context;
 778
 779         context = scic_sds_remote_device_build_command_context(idev, request);
 780
 781         scic_sds_controller_post_request(
 782                 scic_sds_remote_device_get_controller(idev),
 783                 context
 784                 );
 785 }
 786
 787 /* called once the remote node context has transisitioned to a
 788  * ready state.  This is the indication that the remote device object can also
 789  * transition to ready.
 790  */
 791 static void remote_device_resume_done(void *_dev)
 792 {
 793         struct isci_remote_device *idev = _dev;
 794
 795         if (is_remote_device_ready(idev))
 796                 return;
 797
 798         /* go 'ready' if we are not already in a ready state */
 799         sci_change_state(&idev->sm, SCI_DEV_READY);
 800 }
 801
 802 static void scic_sds_stp_remote_device_ready_idle_substate_resume_complete_handler(void *_dev)
 803 {
 804         struct isci_remote_device *idev = _dev;
 805         struct scic_sds_controller *scic = idev->owning_port->owning_controller;
 806
 807         /* For NCQ operation we do not issue a isci_remote_device_not_ready().
 808          * As a result, avoid sending the ready notification.
 809          */
 810         if (idev->sm.previous_state_id != SCI_STP_DEV_NCQ)
 811                 isci_remote_device_ready(scic_to_ihost(scic), idev);
 812 }
 813
 814 static void scic_sds_remote_device_initial_state_enter(struct sci_base_state_machine *sm)
 815 {
 816         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 817
 818         /* Initial state is a transitional state to the stopped state */
 819         sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 820 }
 821
 822 /**
 823  * scic_remote_device_destruct() - free remote node context and destruct
 824  * @remote_device: This parameter specifies the remote device to be destructed.
 825  *
 826  * Remote device objects are a limited resource.  As such, they must be
 827  * protected.  Thus calls to construct and destruct are mutually exclusive and
 828  * non-reentrant. The return value shall indicate if the device was
 829  * successfully destructed or if some failure occurred. enum sci_status This value
 830  * is returned if the device is successfully destructed.
 831  * SCI_FAILURE_INVALID_REMOTE_DEVICE This value is returned if the supplied
 832  * device isn't valid (e.g. it's already been destoryed, the handle isn't
 833  * valid, etc.).
 834  */
 835 static enum sci_status scic_remote_device_destruct(struct isci_remote_device *idev)
 836 {
 837         struct sci_base_state_machine *sm = &idev->sm;
 838         enum scic_sds_remote_device_states state = sm->current_state_id;
 839         struct scic_sds_controller *scic;
 840
 841         if (state != SCI_DEV_STOPPED) {
 842                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 843                          __func__, state);
 844                 return SCI_FAILURE_INVALID_STATE;
 845         }
 846
 847         scic = idev->owning_port->owning_controller;
 848         scic_sds_controller_free_remote_node_context(scic, idev,
 849                                                      idev->rnc.remote_node_index);
 850         idev->rnc.remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
 851         sci_change_state(sm, SCI_DEV_FINAL);
 852
 853         return SCI_SUCCESS;
 854 }
 855
 856 /**
 857  * isci_remote_device_deconstruct() - This function frees an isci_remote_device.
 858  * @ihost: This parameter specifies the isci host object.
 859  * @idev: This parameter specifies the remote device to be freed.
 860  *
 861  */
 862 static void isci_remote_device_deconstruct(struct isci_host *ihost, struct isci_remote_device *idev)
 863 {
 864         dev_dbg(&ihost->pdev->dev,
 865                 "%s: isci_device = %p\n", __func__, idev);
 866
 867         /* There should not be any outstanding io's. All paths to
 868          * here should go through isci_remote_device_nuke_requests.
 869          * If we hit this condition, we will need a way to complete
 870          * io requests in process */
 871         BUG_ON(!list_empty(&idev->reqs_in_process));
 872
 873         scic_remote_device_destruct(idev);
 874         list_del_init(&idev->node);
 875         isci_put_device(idev);
 876 }
 877
 878 static void scic_sds_remote_device_stopped_state_enter(struct sci_base_state_machine *sm)
 879 {
 880         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 881         struct scic_sds_controller *scic = idev->owning_port->owning_controller;
 882         u32 prev_state;
 883
 884         /* If we are entering from the stopping state let the SCI User know that
 885          * the stop operation has completed.
 886          */
 887         prev_state = idev->sm.previous_state_id;
 888         if (prev_state == SCI_DEV_STOPPING)
 889                 isci_remote_device_deconstruct(scic_to_ihost(scic), idev);
 890
 891         scic_sds_controller_remote_device_stopped(scic, idev);
 892 }
 893
 894 static void scic_sds_remote_device_starting_state_enter(struct sci_base_state_machine *sm)
 895 {
 896         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 897         struct scic_sds_controller *scic = scic_sds_remote_device_get_controller(idev);
 898         struct isci_host *ihost = scic_to_ihost(scic);
 899
 900         isci_remote_device_not_ready(ihost, idev,
 901                                      SCIC_REMOTE_DEVICE_NOT_READY_START_REQUESTED);
 902 }
 903
 904 static void scic_sds_remote_device_ready_state_enter(struct sci_base_state_machine *sm)
 905 {
 906         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 907         struct scic_sds_controller *scic = idev->owning_port->owning_controller;
 908         struct domain_device *dev = idev->domain_dev;
 909
 910         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_SATA)) {
 911                 sci_change_state(&idev->sm, SCI_STP_DEV_IDLE);
 912         } else if (dev_is_expander(dev)) {
 913                 sci_change_state(&idev->sm, SCI_SMP_DEV_IDLE);
 914         } else
 915                 isci_remote_device_ready(scic_to_ihost(scic), idev);
 916 }
 917
 918 static void scic_sds_remote_device_ready_state_exit(struct sci_base_state_machine *sm)
 919 {
 920         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 921         struct domain_device *dev = idev->domain_dev;
 922
 923         if (dev->dev_type == SAS_END_DEV) {
 924                 struct scic_sds_controller *scic = idev->owning_port->owning_controller;
 925
 926                 isci_remote_device_not_ready(scic_to_ihost(scic), idev,
 927                                              SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED);
 928         }
 929 }
 930
 931 static void scic_sds_remote_device_resetting_state_enter(struct sci_base_state_machine *sm)
 932 {
 933         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 934
 935         scic_sds_remote_node_context_suspend(
 936                 &idev->rnc, SCI_SOFTWARE_SUSPENSION, NULL, NULL);
 937 }
 938
 939 static void scic_sds_remote_device_resetting_state_exit(struct sci_base_state_machine *sm)
 940 {
 941         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 942
 943         scic_sds_remote_node_context_resume(&idev->rnc, NULL, NULL);
 944 }
 945
 946 static void scic_sds_stp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
 947 {
 948         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 949
 950         idev->working_request = NULL;
 951         if (scic_sds_remote_node_context_is_ready(&idev->rnc)) {
 952                 /*
 953                  * Since the RNC is ready, it's alright to finish completion
 954                  * processing (e.g. signal the remote device is ready). */
 955                 scic_sds_stp_remote_device_ready_idle_substate_resume_complete_handler(idev);
 956         } else {
 957                 scic_sds_remote_node_context_resume(&idev->rnc,
 958                         scic_sds_stp_remote_device_ready_idle_substate_resume_complete_handler,
 959                         idev);
 960         }
 961 }
 962
 963 static void scic_sds_stp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
 964 {
 965         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 966         struct scic_sds_controller *scic = scic_sds_remote_device_get_controller(idev);
 967
 968         BUG_ON(idev->working_request == NULL);
 969
 970         isci_remote_device_not_ready(scic_to_ihost(scic), idev,
 971                                      SCIC_REMOTE_DEVICE_NOT_READY_SATA_REQUEST_STARTED);
 972 }
 973
 974 static void scic_sds_stp_remote_device_ready_ncq_error_substate_enter(struct sci_base_state_machine *sm)
 975 {
 976         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 977         struct scic_sds_controller *scic = scic_sds_remote_device_get_controller(idev);
 978
 979         if (idev->not_ready_reason == SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED)
 980                 isci_remote_device_not_ready(scic_to_ihost(scic), idev,
 981                                              idev->not_ready_reason);
 982 }
 983
 984 static void scic_sds_smp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
 985 {
 986         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 987         struct scic_sds_controller *scic = scic_sds_remote_device_get_controller(idev);
 988
 989         isci_remote_device_ready(scic_to_ihost(scic), idev);
 990 }
 991
 992 static void scic_sds_smp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
 993 {
 994         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 995         struct scic_sds_controller *scic = scic_sds_remote_device_get_controller(idev);
 996
 997         BUG_ON(idev->working_request == NULL);
 998
 999         isci_remote_device_not_ready(scic_to_ihost(scic), idev,
1000                                      SCIC_REMOTE_DEVICE_NOT_READY_SMP_REQUEST_STARTED);
1001 }
1002
1003 static void scic_sds_smp_remote_device_ready_cmd_substate_exit(struct sci_base_state_machine *sm)
1004 {
1005         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1006
1007         idev->working_request = NULL;
1008 }
1009
1010 static const struct sci_base_state scic_sds_remote_device_state_table[] = {
1011         [SCI_DEV_INITIAL] = {
1012                 .enter_state = scic_sds_remote_device_initial_state_enter,
1013         },
1014         [SCI_DEV_STOPPED] = {
1015                 .enter_state = scic_sds_remote_device_stopped_state_enter,
1016         },
1017         [SCI_DEV_STARTING] = {
1018                 .enter_state = scic_sds_remote_device_starting_state_enter,
1019         },
1020         [SCI_DEV_READY] = {
1021                 .enter_state = scic_sds_remote_device_ready_state_enter,
1022                 .exit_state  = scic_sds_remote_device_ready_state_exit
1023         },
1024         [SCI_STP_DEV_IDLE] = {
1025                 .enter_state = scic_sds_stp_remote_device_ready_idle_substate_enter,
1026         },
1027         [SCI_STP_DEV_CMD] = {
1028                 .enter_state = scic_sds_stp_remote_device_ready_cmd_substate_enter,
1029         },
1030         [SCI_STP_DEV_NCQ] = { },
1031         [SCI_STP_DEV_NCQ_ERROR] = {
1032                 .enter_state = scic_sds_stp_remote_device_ready_ncq_error_substate_enter,
1033         },
1034         [SCI_STP_DEV_AWAIT_RESET] = { },
1035         [SCI_SMP_DEV_IDLE] = {
1036                 .enter_state = scic_sds_smp_remote_device_ready_idle_substate_enter,
1037         },
1038         [SCI_SMP_DEV_CMD] = {
1039                 .enter_state = scic_sds_smp_remote_device_ready_cmd_substate_enter,
1040                 .exit_state  = scic_sds_smp_remote_device_ready_cmd_substate_exit,
1041         },
1042         [SCI_DEV_STOPPING] = { },
1043         [SCI_DEV_FAILED] = { },
1044         [SCI_DEV_RESETTING] = {
1045                 .enter_state = scic_sds_remote_device_resetting_state_enter,
1046                 .exit_state  = scic_sds_remote_device_resetting_state_exit
1047         },
1048         [SCI_DEV_FINAL] = { },
1049 };
1050
1051 /**
1052  * scic_remote_device_construct() - common construction
1053  * @sci_port: SAS/SATA port through which this device is accessed.
1054  * @sci_dev: remote device to construct
1055  *
1056  * This routine just performs benign initialization and does not
1057  * allocate the remote_node_context which is left to
1058  * scic_remote_device_[de]a_construct().  scic_remote_device_destruct()
1059  * frees the remote_node_context(s) for the device.
1060  */
1061 static void scic_remote_device_construct(struct isci_port *iport,
1062                                   struct isci_remote_device *idev)
1063 {
1064         idev->owning_port = iport;
1065         idev->started_request_count = 0;
1066
1067         sci_init_sm(&idev->sm, scic_sds_remote_device_state_table, SCI_DEV_INITIAL);
1068
1069         scic_sds_remote_node_context_construct(&idev->rnc,
1070                                                SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX);
1071 }
1072
1073 /**
1074  * scic_remote_device_da_construct() - construct direct attached device.
1075  *
1076  * The information (e.g. IAF, Signature FIS, etc.) necessary to build
1077  * the device is known to the SCI Core since it is contained in the
1078  * scic_phy object.  Remote node context(s) is/are a global resource
1079  * allocated by this routine, freed by scic_remote_device_destruct().
1080  *
1081  * Returns:
1082  * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
1083  * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
1084  * sata-only controller instance.
1085  * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
1086  */
1087 static enum sci_status scic_remote_device_da_construct(struct isci_port *iport,
1088                                                        struct isci_remote_device *idev)
1089 {
1090         enum sci_status status;
1091         struct domain_device *dev = idev->domain_dev;
1092
1093         scic_remote_device_construct(iport, idev);
1094
1095         /*
1096          * This information is request to determine how many remote node context
1097          * entries will be needed to store the remote node.
1098          */
1099         idev->is_direct_attached = true;
1100         status = scic_sds_controller_allocate_remote_node_context(iport->owning_controller,
1101                                                                   idev,
1102                                                                   &idev->rnc.remote_node_index);
1103
1104         if (status != SCI_SUCCESS)
1105                 return status;
1106
1107         if (dev->dev_type == SAS_END_DEV || dev->dev_type == SATA_DEV ||
1108             (dev->tproto & SAS_PROTOCOL_STP) || dev_is_expander(dev))
1109                 /* pass */;
1110         else
1111                 return SCI_FAILURE_UNSUPPORTED_PROTOCOL;
1112
1113         idev->connection_rate = scic_sds_port_get_max_allowed_speed(iport);
1114
1115         /* / @todo Should I assign the port width by reading all of the phys on the port? */
1116         idev->device_port_width = 1;
1117
1118         return SCI_SUCCESS;
1119 }
1120
1121 /**
1122  * scic_remote_device_ea_construct() - construct expander attached device
1123  *
1124  * Remote node context(s) is/are a global resource allocated by this
1125  * routine, freed by scic_remote_device_destruct().
1126  *
1127  * Returns:
1128  * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
1129  * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
1130  * sata-only controller instance.
1131  * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
1132  */
1133 static enum sci_status scic_remote_device_ea_construct(struct isci_port *iport,
1134                                                        struct isci_remote_device *idev)
1135 {
1136         struct domain_device *dev = idev->domain_dev;
1137         enum sci_status status;
1138
1139         scic_remote_device_construct(iport, idev);
1140
1141         status = scic_sds_controller_allocate_remote_node_context(iport->owning_controller,
1142                                                                   idev,
1143                                                                   &idev->rnc.remote_node_index);
1144         if (status != SCI_SUCCESS)
1145                 return status;
1146
1147         if (dev->dev_type == SAS_END_DEV || dev->dev_type == SATA_DEV ||
1148             (dev->tproto & SAS_PROTOCOL_STP) || dev_is_expander(dev))
1149                 /* pass */;
1150         else
1151                 return SCI_FAILURE_UNSUPPORTED_PROTOCOL;
1152
1153         /*
1154          * For SAS-2 the physical link rate is actually a logical link
1155          * rate that incorporates multiplexing.  The SCU doesn't
1156          * incorporate multiplexing and for the purposes of the
1157          * connection the logical link rate is that same as the
1158          * physical.  Furthermore, the SAS-2 and SAS-1.1 fields overlay
1159          * one another, so this code works for both situations. */
1160         idev->connection_rate = min_t(u16, scic_sds_port_get_max_allowed_speed(iport),
1161                                          dev->linkrate);
1162
1163         /* / @todo Should I assign the port width by reading all of the phys on the port? */
1164         idev->device_port_width = 1;
1165
1166         return SCI_SUCCESS;
1167 }
1168
1169 /**
1170  * scic_remote_device_start() - This method will start the supplied remote
1171  *    device.  This method enables normal IO requests to flow through to the
1172  *    remote device.
1173  * @remote_device: This parameter specifies the device to be started.
1174  * @timeout: This parameter specifies the number of milliseconds in which the
1175  *    start operation should complete.
1176  *
1177  * An indication of whether the device was successfully started. SCI_SUCCESS
1178  * This value is returned if the device was successfully started.
1179  * SCI_FAILURE_INVALID_PHY This value is returned if the user attempts to start
1180  * the device when there have been no phys added to it.
1181  */
1182 static enum sci_status scic_remote_device_start(struct isci_remote_device *idev,
1183                                                 u32 timeout)
1184 {
1185         struct sci_base_state_machine *sm = &idev->sm;
1186         enum scic_sds_remote_device_states state = sm->current_state_id;
1187         enum sci_status status;
1188
1189         if (state != SCI_DEV_STOPPED) {
1190                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
1191                          __func__, state);
1192                 return SCI_FAILURE_INVALID_STATE;
1193         }
1194
1195         status = scic_sds_remote_node_context_resume(&idev->rnc,
1196                                                      remote_device_resume_done,
1197                                                      idev);
1198         if (status != SCI_SUCCESS)
1199                 return status;
1200
1201         sci_change_state(sm, SCI_DEV_STARTING);
1202
1203         return SCI_SUCCESS;
1204 }
1205
1206 static enum sci_status isci_remote_device_construct(struct isci_port *iport,
1207                                                     struct isci_remote_device *idev)
1208 {
1209         struct isci_host *ihost = iport->isci_host;
1210         struct domain_device *dev = idev->domain_dev;
1211         enum sci_status status;
1212
1213         if (dev->parent && dev_is_expander(dev->parent))
1214                 status = scic_remote_device_ea_construct(iport, idev);
1215         else
1216                 status = scic_remote_device_da_construct(iport, idev);
1217
1218         if (status != SCI_SUCCESS) {
1219                 dev_dbg(&ihost->pdev->dev, "%s: construct failed: %d\n",
1220                         __func__, status);
1221
1222                 return status;
1223         }
1224
1225         /* start the device. */
1226         status = scic_remote_device_start(idev, ISCI_REMOTE_DEVICE_START_TIMEOUT);
1227
1228         if (status != SCI_SUCCESS)
1229                 dev_warn(&ihost->pdev->dev, "remote device start failed: %d\n",
1230                          status);
1231
1232         return status;
1233 }
1234
1235 void isci_remote_device_nuke_requests(struct isci_host *ihost, struct isci_remote_device *idev)
1236 {
1237         DECLARE_COMPLETION_ONSTACK(aborted_task_completion);
1238
1239         dev_dbg(&ihost->pdev->dev,
1240                 "%s: idev = %p\n", __func__, idev);
1241
1242         /* Cleanup all requests pending for this device. */
1243         isci_terminate_pending_requests(ihost, idev);
1244
1245         dev_dbg(&ihost->pdev->dev,
1246                 "%s: idev = %p, done\n", __func__, idev);
1247 }
1248
1249 /**
1250  * This function builds the isci_remote_device when a libsas dev_found message
1251  *    is received.
1252  * @isci_host: This parameter specifies the isci host object.
1253  * @port: This parameter specifies the isci_port conected to this device.
1254  *
1255  * pointer to new isci_remote_device.
1256  */
1257 static struct isci_remote_device *
1258 isci_remote_device_alloc(struct isci_host *ihost, struct isci_port *iport)
1259 {
1260         struct isci_remote_device *idev;
1261         int i;
1262
1263         for (i = 0; i < SCI_MAX_REMOTE_DEVICES; i++) {
1264                 idev = &ihost->devices[i];
1265                 if (!test_and_set_bit(IDEV_ALLOCATED, &idev->flags))
1266                         break;
1267         }
1268
1269         if (i >= SCI_MAX_REMOTE_DEVICES) {
1270                 dev_warn(&ihost->pdev->dev, "%s: failed\n", __func__);
1271                 return NULL;
1272         }
1273
1274         if (WARN_ONCE(!list_empty(&idev->reqs_in_process), "found requests in process\n"))
1275                 return NULL;
1276
1277         if (WARN_ONCE(!list_empty(&idev->node), "found non-idle remote device\n"))
1278                 return NULL;
1279
1280         return idev;
1281 }
1282
1283 void isci_remote_device_release(struct kref *kref)
1284 {
1285         struct isci_remote_device *idev = container_of(kref, typeof(*idev), kref);
1286         struct isci_host *ihost = idev->isci_port->isci_host;
1287
1288         idev->domain_dev = NULL;
1289         idev->isci_port = NULL;
1290         clear_bit(IDEV_START_PENDING, &idev->flags);
1291         clear_bit(IDEV_STOP_PENDING, &idev->flags);
1292         clear_bit(IDEV_IO_READY, &idev->flags);
1293         clear_bit(IDEV_GONE, &idev->flags);
1294         clear_bit(IDEV_EH, &idev->flags);
1295         smp_mb__before_clear_bit();
1296         clear_bit(IDEV_ALLOCATED, &idev->flags);
1297         wake_up(&ihost->eventq);
1298 }
1299
1300 /**
1301  * isci_remote_device_stop() - This function is called internally to stop the
1302  *    remote device.
1303  * @isci_host: This parameter specifies the isci host object.
1304  * @isci_device: This parameter specifies the remote device.
1305  *
1306  * The status of the scic request to stop.
1307  */
1308 enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_remote_device *idev)
1309 {
1310         enum sci_status status;
1311         unsigned long flags;
1312
1313         dev_dbg(&ihost->pdev->dev,
1314                 "%s: isci_device = %p\n", __func__, idev);
1315
1316         spin_lock_irqsave(&ihost->scic_lock, flags);
1317         idev->domain_dev->lldd_dev = NULL; /* disable new lookups */
1318         set_bit(IDEV_GONE, &idev->flags);
1319         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1320
1321         /* Kill all outstanding requests. */
1322         isci_remote_device_nuke_requests(ihost, idev);
1323
1324         set_bit(IDEV_STOP_PENDING, &idev->flags);
1325
1326         spin_lock_irqsave(&ihost->scic_lock, flags);
1327         status = scic_remote_device_stop(idev, 50);
1328         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1329
1330         /* Wait for the stop complete callback. */
1331         if (WARN_ONCE(status != SCI_SUCCESS, "failed to stop device\n"))
1332                 /* nothing to wait for */;
1333         else
1334                 wait_for_device_stop(ihost, idev);
1335
1336         return status;
1337 }
1338
1339 /**
1340  * isci_remote_device_gone() - This function is called by libsas when a domain
1341  *    device is removed.
1342  * @domain_device: This parameter specifies the libsas domain device.
1343  *
1344  */
1345 void isci_remote_device_gone(struct domain_device *dev)
1346 {
1347         struct isci_host *ihost = dev_to_ihost(dev);
1348         struct isci_remote_device *idev = dev->lldd_dev;
1349
1350         dev_dbg(&ihost->pdev->dev,
1351                 "%s: domain_device = %p, isci_device = %p, isci_port = %p\n",
1352                 __func__, dev, idev, idev->isci_port);
1353
1354         isci_remote_device_stop(ihost, idev);
1355 }
1356
1357
1358 /**
1359  * isci_remote_device_found() - This function is called by libsas when a remote
1360  *    device is discovered. A remote device object is created and started. the
1361  *    function then sleeps until the sci core device started message is
1362  *    received.
1363  * @domain_device: This parameter specifies the libsas domain device.
1364  *
1365  * status, zero indicates success.
1366  */
1367 int isci_remote_device_found(struct domain_device *domain_dev)
1368 {
1369         struct isci_host *isci_host = dev_to_ihost(domain_dev);
1370         struct isci_port *isci_port;
1371         struct isci_phy *isci_phy;
1372         struct asd_sas_port *sas_port;
1373         struct asd_sas_phy *sas_phy;
1374         struct isci_remote_device *isci_device;
1375         enum sci_status status;
1376
1377         dev_dbg(&isci_host->pdev->dev,
1378                 "%s: domain_device = %p\n", __func__, domain_dev);
1379
1380         wait_for_start(isci_host);
1381
1382         sas_port = domain_dev->port;
1383         sas_phy = list_first_entry(&sas_port->phy_list, struct asd_sas_phy,
1384                                    port_phy_el);
1385         isci_phy = to_iphy(sas_phy);
1386         isci_port = isci_phy->isci_port;
1387
1388         /* we are being called for a device on this port,
1389          * so it has to come up eventually
1390          */
1391         wait_for_completion(&isci_port->start_complete);
1392
1393         if ((isci_stopping == isci_port_get_state(isci_port)) ||
1394             (isci_stopped == isci_port_get_state(isci_port)))
1395                 return -ENODEV;
1396
1397         isci_device = isci_remote_device_alloc(isci_host, isci_port);
1398         if (!isci_device)
1399                 return -ENODEV;
1400
1401         kref_init(&isci_device->kref);
1402         INIT_LIST_HEAD(&isci_device->node);
1403
1404         spin_lock_irq(&isci_host->scic_lock);
1405         isci_device->domain_dev = domain_dev;
1406         isci_device->isci_port = isci_port;
1407         list_add_tail(&isci_device->node, &isci_port->remote_dev_list);
1408
1409         set_bit(IDEV_START_PENDING, &isci_device->flags);
1410         status = isci_remote_device_construct(isci_port, isci_device);
1411
1412         dev_dbg(&isci_host->pdev->dev,
1413                 "%s: isci_device = %p\n",
1414                 __func__, isci_device);
1415
1416         if (status == SCI_SUCCESS) {
1417                 /* device came up, advertise it to the world */
1418                 domain_dev->lldd_dev = isci_device;
1419         } else
1420                 isci_put_device(isci_device);
1421         spin_unlock_irq(&isci_host->scic_lock);
1422
1423         /* wait for the device ready callback. */
1424         wait_for_device_start(isci_host, isci_device);
1425
1426         return status == SCI_SUCCESS ? 0 : -ENODEV;
1427 }
1428 /**
1429  * isci_device_is_reset_pending() - This function will check if there is any
1430  *    pending reset condition on the device.
1431  * @request: This parameter is the isci_device object.
1432  *
1433  * true if there is a reset pending for the device.
1434  */
1435 bool isci_device_is_reset_pending(
1436         struct isci_host *isci_host,
1437         struct isci_remote_device *isci_device)
1438 {
1439         struct isci_request *isci_request;
1440         struct isci_request *tmp_req;
1441         bool reset_is_pending = false;
1442         unsigned long flags;
1443
1444         dev_dbg(&isci_host->pdev->dev,
1445                 "%s: isci_device = %p\n", __func__, isci_device);
1446
1447         spin_lock_irqsave(&isci_host->scic_lock, flags);
1448
1449         /* Check for reset on all pending requests. */
1450         list_for_each_entry_safe(isci_request, tmp_req,
1451                                  &isci_device->reqs_in_process, dev_node) {
1452                 dev_dbg(&isci_host->pdev->dev,
1453                         "%s: isci_device = %p request = %p\n",
1454                         __func__, isci_device, isci_request);
1455
1456                 if (isci_request->ttype == io_task) {
1457                         struct sas_task *task = isci_request_access_task(
1458                                 isci_request);
1459
1460                         spin_lock(&task->task_state_lock);
1461                         if (task->task_state_flags & SAS_TASK_NEED_DEV_RESET)
1462                                 reset_is_pending = true;
1463                         spin_unlock(&task->task_state_lock);
1464                 }
1465         }
1466
1467         spin_unlock_irqrestore(&isci_host->scic_lock, flags);
1468
1469         dev_dbg(&isci_host->pdev->dev,
1470                 "%s: isci_device = %p reset_is_pending = %d\n",
1471                 __func__, isci_device, reset_is_pending);
1472
1473         return reset_is_pending;
1474 }
1475
1476 /**
1477  * isci_device_clear_reset_pending() - This function will clear if any pending
1478  *    reset condition flags on the device.
1479  * @request: This parameter is the isci_device object.
1480  *
1481  * true if there is a reset pending for the device.
1482  */
1483 void isci_device_clear_reset_pending(struct isci_host *ihost, struct isci_remote_device *idev)
1484 {
1485         struct isci_request *isci_request;
1486         struct isci_request *tmp_req;
1487         unsigned long flags = 0;
1488
1489         dev_dbg(&ihost->pdev->dev, "%s: idev=%p, ihost=%p\n",
1490                  __func__, idev, ihost);
1491
1492         spin_lock_irqsave(&ihost->scic_lock, flags);
1493
1494         /* Clear reset pending on all pending requests. */
1495         list_for_each_entry_safe(isci_request, tmp_req,
1496                                  &idev->reqs_in_process, dev_node) {
1497                 dev_dbg(&ihost->pdev->dev, "%s: idev = %p request = %p\n",
1498                          __func__, idev, isci_request);
1499
1500                 if (isci_request->ttype == io_task) {
1501
1502                         unsigned long flags2;
1503                         struct sas_task *task = isci_request_access_task(
1504                                 isci_request);
1505
1506                         spin_lock_irqsave(&task->task_state_lock, flags2);
1507                         task->task_state_flags &= ~SAS_TASK_NEED_DEV_RESET;
1508                         spin_unlock_irqrestore(&task->task_state_lock, flags2);
1509                 }
1510         }
1511         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1512 }