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 <linux/bitops.h>
  57 #include "isci.h"
  58 #include "port.h"
  59 #include "remote_device.h"
  60 #include "request.h"
  61 #include "remote_node_context.h"
  62 #include "scu_event_codes.h"
  63 #include "task.h"
  64
  65 /**
  66  * isci_remote_device_not_ready() - This function is called by the ihost when
  67  *    the remote device is not ready. We mark the isci device as ready (not
  68  *    "ready_for_io") and signal the waiting proccess.
  69  * @isci_host: This parameter specifies the isci host object.
  70  * @isci_device: This parameter specifies the remote device
  71  *
  72  * sci_lock is held on entrance to this function.
  73  */
  74 static void isci_remote_device_not_ready(struct isci_host *ihost,
  75                                   struct isci_remote_device *idev, u32 reason)
  76 {
  77         struct isci_request *ireq;
  78
  79         dev_dbg(&ihost->pdev->dev,
  80                 "%s: isci_device = %p\n", __func__, idev);
  81
  82         switch (reason) {
  83         case SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED:
  84                 set_bit(IDEV_GONE, &idev->flags);
  85                 break;
  86         case SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED:
  87                 set_bit(IDEV_IO_NCQERROR, &idev->flags);
  88
  89                 /* Kill all outstanding requests for the device. */
  90                 list_for_each_entry(ireq, &idev->reqs_in_process, dev_node) {
  91
  92                         dev_dbg(&ihost->pdev->dev,
  93                                 "%s: isci_device = %p request = %p\n",
  94                                 __func__, idev, ireq);
  95
  96                         sci_controller_terminate_request(ihost,
  97                                                           idev,
  98                                                           ireq);
  99                 }
 100                 /* Fall through into the default case... */
 101         default:
 102                 clear_bit(IDEV_IO_READY, &idev->flags);
 103                 break;
 104         }
 105 }
 106
 107 /**
 108  * isci_remote_device_ready() - This function is called by the ihost when the
 109  *    remote device is ready. We mark the isci device as ready and signal the
 110  *    waiting proccess.
 111  * @ihost: our valid isci_host
 112  * @idev: remote device
 113  *
 114  */
 115 static void isci_remote_device_ready(struct isci_host *ihost, struct isci_remote_device *idev)
 116 {
 117         dev_dbg(&ihost->pdev->dev,
 118                 "%s: idev = %p\n", __func__, idev);
 119
 120         clear_bit(IDEV_IO_NCQERROR, &idev->flags);
 121         set_bit(IDEV_IO_READY, &idev->flags);
 122         if (test_and_clear_bit(IDEV_START_PENDING, &idev->flags))
 123                 wake_up(&ihost->eventq);
 124 }
 125
 126 /* called once the remote node context is ready to be freed.
 127  * The remote device can now report that its stop operation is complete. none
 128  */
 129 static void rnc_destruct_done(void *_dev)
 130 {
 131         struct isci_remote_device *idev = _dev;
 132
 133         BUG_ON(idev->started_request_count != 0);
 134         sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 135 }
 136
 137 static enum sci_status sci_remote_device_terminate_requests(struct isci_remote_device *idev)
 138 {
 139         struct isci_host *ihost = idev->owning_port->owning_controller;
 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 = sci_controller_terminate_request(ihost, idev, ireq);
 152                 if (s != SCI_SUCCESS)
 153                         status = s;
 154         }
 155
 156         return status;
 157 }
 158
 159 enum sci_status sci_remote_device_stop(struct isci_remote_device *idev,
 160                                         u32 timeout)
 161 {
 162         struct sci_base_state_machine *sm = &idev->sm;
 163         enum sci_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                 sci_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                         sci_remote_node_context_destruct(&idev->rnc,
 196                                                               rnc_destruct_done, idev);
 197                         return SCI_SUCCESS;
 198                 } else
 199                         return sci_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 sci_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 sci_remote_device_reset(struct isci_remote_device *idev)
 214 {
 215         struct sci_base_state_machine *sm = &idev->sm;
 216         enum sci_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 sci_remote_device_reset_complete(struct isci_remote_device *idev)
 244 {
 245         struct sci_base_state_machine *sm = &idev->sm;
 246         enum sci_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 sci_remote_device_suspend(struct isci_remote_device *idev,
 259                                                u32 suspend_type)
 260 {
 261         struct sci_base_state_machine *sm = &idev->sm;
 262         enum sci_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 sci_remote_node_context_suspend(&idev->rnc,
 271                                                     suspend_type, NULL, NULL);
 272 }
 273
 274 enum sci_status sci_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 sci_remote_device_states state = sm->current_state_id;
 279         struct isci_host *ihost = 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                 sci_controller_release_frame(ihost, 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 = sci_unsolicited_frame_control_get_header(&ihost->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 = sci_request_by_tag(ihost, 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 = sci_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                         sci_controller_release_frame(ihost, frame_index);
 324                 }
 325                 break;
 326         }
 327         case SCI_STP_DEV_NCQ: {
 328                 struct dev_to_host_fis *hdr;
 329
 330                 status = sci_unsolicited_frame_control_get_header(&ihost->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                 sci_controller_release_frame(ihost, 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 = sci_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 sci_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 /*
 391  * called once the remote node context has transisitioned to a ready
 392  * state (after suspending RX and/or TX due to early D2H fis)
 393  */
 394 static void atapi_remote_device_resume_done(void *_dev)
 395 {
 396         struct isci_remote_device *idev = _dev;
 397         struct isci_request *ireq = idev->working_request;
 398
 399         sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
 400 }
 401
 402 enum sci_status sci_remote_device_event_handler(struct isci_remote_device *idev,
 403                                                      u32 event_code)
 404 {
 405         struct sci_base_state_machine *sm = &idev->sm;
 406         enum sci_remote_device_states state = sm->current_state_id;
 407         enum sci_status status;
 408
 409         switch (scu_get_event_type(event_code)) {
 410         case SCU_EVENT_TYPE_RNC_OPS_MISC:
 411         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 412         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 413                 status = sci_remote_node_context_event_handler(&idev->rnc, event_code);
 414                 break;
 415         case SCU_EVENT_TYPE_PTX_SCHEDULE_EVENT:
 416                 if (scu_get_event_code(event_code) == SCU_EVENT_IT_NEXUS_TIMEOUT) {
 417                         status = SCI_SUCCESS;
 418
 419                         /* Suspend the associated RNC */
 420                         sci_remote_node_context_suspend(&idev->rnc,
 421                                                               SCI_SOFTWARE_SUSPENSION,
 422                                                               NULL, NULL);
 423
 424                         dev_dbg(scirdev_to_dev(idev),
 425                                 "%s: device: %p event code: %x: %s\n",
 426                                 __func__, idev, event_code,
 427                                 is_remote_device_ready(idev)
 428                                 ? "I_T_Nexus_Timeout event"
 429                                 : "I_T_Nexus_Timeout event in wrong state");
 430
 431                         break;
 432                 }
 433         /* Else, fall through and treat as unhandled... */
 434         default:
 435                 dev_dbg(scirdev_to_dev(idev),
 436                         "%s: device: %p event code: %x: %s\n",
 437                         __func__, idev, event_code,
 438                         is_remote_device_ready(idev)
 439                         ? "unexpected event"
 440                         : "unexpected event in wrong state");
 441                 status = SCI_FAILURE_INVALID_STATE;
 442                 break;
 443         }
 444
 445         if (status != SCI_SUCCESS)
 446                 return status;
 447
 448         if (state == SCI_STP_DEV_ATAPI_ERROR) {
 449                 /* For ATAPI error state resume the RNC right away. */
 450                 if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
 451                     scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX) {
 452                         return sci_remote_node_context_resume(&idev->rnc,
 453                                                               atapi_remote_device_resume_done,
 454                                                               idev);
 455                 }
 456         }
 457
 458         if (state == SCI_STP_DEV_IDLE) {
 459
 460                 /* We pick up suspension events to handle specifically to this
 461                  * state. We resume the RNC right away.
 462                  */
 463                 if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
 464                     scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX)
 465                         status = sci_remote_node_context_resume(&idev->rnc, NULL, NULL);
 466         }
 467
 468         return status;
 469 }
 470
 471 static void sci_remote_device_start_request(struct isci_remote_device *idev,
 472                                                  struct isci_request *ireq,
 473                                                  enum sci_status status)
 474 {
 475         struct isci_port *iport = idev->owning_port;
 476
 477         /* cleanup requests that failed after starting on the port */
 478         if (status != SCI_SUCCESS)
 479                 sci_port_complete_io(iport, idev, ireq);
 480         else {
 481                 kref_get(&idev->kref);
 482                 idev->started_request_count++;
 483         }
 484 }
 485
 486 enum sci_status sci_remote_device_start_io(struct isci_host *ihost,
 487                                                 struct isci_remote_device *idev,
 488                                                 struct isci_request *ireq)
 489 {
 490         struct sci_base_state_machine *sm = &idev->sm;
 491         enum sci_remote_device_states state = sm->current_state_id;
 492         struct isci_port *iport = idev->owning_port;
 493         enum sci_status status;
 494
 495         switch (state) {
 496         case SCI_DEV_INITIAL:
 497         case SCI_DEV_STOPPED:
 498         case SCI_DEV_STARTING:
 499         case SCI_STP_DEV_NCQ_ERROR:
 500         case SCI_DEV_STOPPING:
 501         case SCI_DEV_FAILED:
 502         case SCI_DEV_RESETTING:
 503         case SCI_DEV_FINAL:
 504         default:
 505                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 506                          __func__, state);
 507                 return SCI_FAILURE_INVALID_STATE;
 508         case SCI_DEV_READY:
 509                 /* attempt to start an io request for this device object. The remote
 510                  * device object will issue the start request for the io and if
 511                  * successful it will start the request for the port object then
 512                  * increment its own request count.
 513                  */
 514                 status = sci_port_start_io(iport, idev, ireq);
 515                 if (status != SCI_SUCCESS)
 516                         return status;
 517
 518                 status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 519                 if (status != SCI_SUCCESS)
 520                         break;
 521
 522                 status = sci_request_start(ireq);
 523                 break;
 524         case SCI_STP_DEV_IDLE: {
 525                 /* handle the start io operation for a sata device that is in
 526                  * the command idle state. - Evalute the type of IO request to
 527                  * be started - If its an NCQ request change to NCQ substate -
 528                  * If its any other command change to the CMD substate
 529                  *
 530                  * If this is a softreset we may want to have a different
 531                  * substate.
 532                  */
 533                 enum sci_remote_device_states new_state;
 534                 struct sas_task *task = isci_request_access_task(ireq);
 535
 536                 status = sci_port_start_io(iport, idev, ireq);
 537                 if (status != SCI_SUCCESS)
 538                         return status;
 539
 540                 status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 541                 if (status != SCI_SUCCESS)
 542                         break;
 543
 544                 status = sci_request_start(ireq);
 545                 if (status != SCI_SUCCESS)
 546                         break;
 547
 548                 if (task->ata_task.use_ncq)
 549                         new_state = SCI_STP_DEV_NCQ;
 550                 else {
 551                         idev->working_request = ireq;
 552                         new_state = SCI_STP_DEV_CMD;
 553                 }
 554                 sci_change_state(sm, new_state);
 555                 break;
 556         }
 557         case SCI_STP_DEV_NCQ: {
 558                 struct sas_task *task = isci_request_access_task(ireq);
 559
 560                 if (task->ata_task.use_ncq) {
 561                         status = sci_port_start_io(iport, idev, ireq);
 562                         if (status != SCI_SUCCESS)
 563                                 return status;
 564
 565                         status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 566                         if (status != SCI_SUCCESS)
 567                                 break;
 568
 569                         status = sci_request_start(ireq);
 570                 } else
 571                         return SCI_FAILURE_INVALID_STATE;
 572                 break;
 573         }
 574         case SCI_STP_DEV_AWAIT_RESET:
 575                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 576         case SCI_SMP_DEV_IDLE:
 577                 status = sci_port_start_io(iport, idev, ireq);
 578                 if (status != SCI_SUCCESS)
 579                         return status;
 580
 581                 status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 582                 if (status != SCI_SUCCESS)
 583                         break;
 584
 585                 status = sci_request_start(ireq);
 586                 if (status != SCI_SUCCESS)
 587                         break;
 588
 589                 idev->working_request = ireq;
 590                 sci_change_state(&idev->sm, SCI_SMP_DEV_CMD);
 591                 break;
 592         case SCI_STP_DEV_CMD:
 593         case SCI_SMP_DEV_CMD:
 594                 /* device is already handling a command it can not accept new commands
 595                  * until this one is complete.
 596                  */
 597                 return SCI_FAILURE_INVALID_STATE;
 598         }
 599
 600         sci_remote_device_start_request(idev, ireq, status);
 601         return status;
 602 }
 603
 604 static enum sci_status common_complete_io(struct isci_port *iport,
 605                                           struct isci_remote_device *idev,
 606                                           struct isci_request *ireq)
 607 {
 608         enum sci_status status;
 609
 610         status = sci_request_complete(ireq);
 611         if (status != SCI_SUCCESS)
 612                 return status;
 613
 614         status = sci_port_complete_io(iport, idev, ireq);
 615         if (status != SCI_SUCCESS)
 616                 return status;
 617
 618         sci_remote_device_decrement_request_count(idev);
 619         return status;
 620 }
 621
 622 enum sci_status sci_remote_device_complete_io(struct isci_host *ihost,
 623                                                    struct isci_remote_device *idev,
 624                                                    struct isci_request *ireq)
 625 {
 626         struct sci_base_state_machine *sm = &idev->sm;
 627         enum sci_remote_device_states state = sm->current_state_id;
 628         struct isci_port *iport = idev->owning_port;
 629         enum sci_status status;
 630
 631         switch (state) {
 632         case SCI_DEV_INITIAL:
 633         case SCI_DEV_STOPPED:
 634         case SCI_DEV_STARTING:
 635         case SCI_STP_DEV_IDLE:
 636         case SCI_SMP_DEV_IDLE:
 637         case SCI_DEV_FAILED:
 638         case SCI_DEV_FINAL:
 639         default:
 640                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 641                          __func__, state);
 642                 return SCI_FAILURE_INVALID_STATE;
 643         case SCI_DEV_READY:
 644         case SCI_STP_DEV_AWAIT_RESET:
 645         case SCI_DEV_RESETTING:
 646                 status = common_complete_io(iport, idev, ireq);
 647                 break;
 648         case SCI_STP_DEV_CMD:
 649         case SCI_STP_DEV_NCQ:
 650         case SCI_STP_DEV_NCQ_ERROR:
 651         case SCI_STP_DEV_ATAPI_ERROR:
 652                 status = common_complete_io(iport, idev, ireq);
 653                 if (status != SCI_SUCCESS)
 654                         break;
 655
 656                 if (ireq->sci_status == SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) {
 657                         /* This request causes hardware error, device needs to be Lun Reset.
 658                          * So here we force the state machine to IDLE state so the rest IOs
 659                          * can reach RNC state handler, these IOs will be completed by RNC with
 660                          * status of "DEVICE_RESET_REQUIRED", instead of "INVALID STATE".
 661                          */
 662                         sci_change_state(sm, SCI_STP_DEV_AWAIT_RESET);
 663                 } else if (idev->started_request_count == 0)
 664                         sci_change_state(sm, SCI_STP_DEV_IDLE);
 665                 break;
 666         case SCI_SMP_DEV_CMD:
 667                 status = common_complete_io(iport, idev, ireq);
 668                 if (status != SCI_SUCCESS)
 669                         break;
 670                 sci_change_state(sm, SCI_SMP_DEV_IDLE);
 671                 break;
 672         case SCI_DEV_STOPPING:
 673                 status = common_complete_io(iport, idev, ireq);
 674                 if (status != SCI_SUCCESS)
 675                         break;
 676
 677                 if (idev->started_request_count == 0)
 678                         sci_remote_node_context_destruct(&idev->rnc,
 679                                                          rnc_destruct_done,
 680                                                          idev);
 681                 break;
 682         }
 683
 684         if (status != SCI_SUCCESS)
 685                 dev_err(scirdev_to_dev(idev),
 686                         "%s: Port:0x%p Device:0x%p Request:0x%p Status:0x%x "
 687                         "could not complete\n", __func__, iport,
 688                         idev, ireq, status);
 689         else
 690                 isci_put_device(idev);
 691
 692         return status;
 693 }
 694
 695 static void sci_remote_device_continue_request(void *dev)
 696 {
 697         struct isci_remote_device *idev = dev;
 698
 699         /* we need to check if this request is still valid to continue. */
 700         if (idev->working_request)
 701                 sci_controller_continue_io(idev->working_request);
 702 }
 703
 704 enum sci_status sci_remote_device_start_task(struct isci_host *ihost,
 705                                                   struct isci_remote_device *idev,
 706                                                   struct isci_request *ireq)
 707 {
 708         struct sci_base_state_machine *sm = &idev->sm;
 709         enum sci_remote_device_states state = sm->current_state_id;
 710         struct isci_port *iport = idev->owning_port;
 711         enum sci_status status;
 712
 713         switch (state) {
 714         case SCI_DEV_INITIAL:
 715         case SCI_DEV_STOPPED:
 716         case SCI_DEV_STARTING:
 717         case SCI_SMP_DEV_IDLE:
 718         case SCI_SMP_DEV_CMD:
 719         case SCI_DEV_STOPPING:
 720         case SCI_DEV_FAILED:
 721         case SCI_DEV_RESETTING:
 722         case SCI_DEV_FINAL:
 723         default:
 724                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 725                          __func__, state);
 726                 return SCI_FAILURE_INVALID_STATE;
 727         case SCI_STP_DEV_IDLE:
 728         case SCI_STP_DEV_CMD:
 729         case SCI_STP_DEV_NCQ:
 730         case SCI_STP_DEV_NCQ_ERROR:
 731         case SCI_STP_DEV_AWAIT_RESET:
 732                 status = sci_port_start_io(iport, idev, ireq);
 733                 if (status != SCI_SUCCESS)
 734                         return status;
 735
 736                 status = sci_remote_node_context_start_task(&idev->rnc, ireq);
 737                 if (status != SCI_SUCCESS)
 738                         goto out;
 739
 740                 status = sci_request_start(ireq);
 741                 if (status != SCI_SUCCESS)
 742                         goto out;
 743
 744                 /* Note: If the remote device state is not IDLE this will
 745                  * replace the request that probably resulted in the task
 746                  * management request.
 747                  */
 748                 idev->working_request = ireq;
 749                 sci_change_state(sm, SCI_STP_DEV_CMD);
 750
 751                 /* The remote node context must cleanup the TCi to NCQ mapping
 752                  * table.  The only way to do this correctly is to either write
 753                  * to the TLCR register or to invalidate and repost the RNC. In
 754                  * either case the remote node context state machine will take
 755                  * the correct action when the remote node context is suspended
 756                  * and later resumed.
 757                  */
 758                 sci_remote_node_context_suspend(&idev->rnc,
 759                                 SCI_SOFTWARE_SUSPENSION, NULL, NULL);
 760                 sci_remote_node_context_resume(&idev->rnc,
 761                                 sci_remote_device_continue_request,
 762                                                     idev);
 763
 764         out:
 765                 sci_remote_device_start_request(idev, ireq, status);
 766                 /* We need to let the controller start request handler know that
 767                  * it can't post TC yet. We will provide a callback function to
 768                  * post TC when RNC gets resumed.
 769                  */
 770                 return SCI_FAILURE_RESET_DEVICE_PARTIAL_SUCCESS;
 771         case SCI_DEV_READY:
 772                 status = sci_port_start_io(iport, idev, ireq);
 773                 if (status != SCI_SUCCESS)
 774                         return status;
 775
 776                 status = sci_remote_node_context_start_task(&idev->rnc, ireq);
 777                 if (status != SCI_SUCCESS)
 778                         break;
 779
 780                 status = sci_request_start(ireq);
 781                 break;
 782         }
 783         sci_remote_device_start_request(idev, ireq, status);
 784
 785         return status;
 786 }
 787
 788 void sci_remote_device_post_request(struct isci_remote_device *idev, u32 request)
 789 {
 790         struct isci_port *iport = idev->owning_port;
 791         u32 context;
 792
 793         context = request |
 794                   (ISCI_PEG << SCU_CONTEXT_COMMAND_PROTOCOL_ENGINE_GROUP_SHIFT) |
 795                   (iport->physical_port_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT) |
 796                   idev->rnc.remote_node_index;
 797
 798         sci_controller_post_request(iport->owning_controller, context);
 799 }
 800
 801 /* called once the remote node context has transisitioned to a
 802  * ready state.  This is the indication that the remote device object can also
 803  * transition to ready.
 804  */
 805 static void remote_device_resume_done(void *_dev)
 806 {
 807         struct isci_remote_device *idev = _dev;
 808
 809         if (is_remote_device_ready(idev))
 810                 return;
 811
 812         /* go 'ready' if we are not already in a ready state */
 813         sci_change_state(&idev->sm, SCI_DEV_READY);
 814 }
 815
 816 static void sci_stp_remote_device_ready_idle_substate_resume_complete_handler(void *_dev)
 817 {
 818         struct isci_remote_device *idev = _dev;
 819         struct isci_host *ihost = idev->owning_port->owning_controller;
 820
 821         /* For NCQ operation we do not issue a isci_remote_device_not_ready().
 822          * As a result, avoid sending the ready notification.
 823          */
 824         if (idev->sm.previous_state_id != SCI_STP_DEV_NCQ)
 825                 isci_remote_device_ready(ihost, idev);
 826 }
 827
 828 static void sci_remote_device_initial_state_enter(struct sci_base_state_machine *sm)
 829 {
 830         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 831
 832         /* Initial state is a transitional state to the stopped state */
 833         sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 834 }
 835
 836 /**
 837  * sci_remote_device_destruct() - free remote node context and destruct
 838  * @remote_device: This parameter specifies the remote device to be destructed.
 839  *
 840  * Remote device objects are a limited resource.  As such, they must be
 841  * protected.  Thus calls to construct and destruct are mutually exclusive and
 842  * non-reentrant. The return value shall indicate if the device was
 843  * successfully destructed or if some failure occurred. enum sci_status This value
 844  * is returned if the device is successfully destructed.
 845  * SCI_FAILURE_INVALID_REMOTE_DEVICE This value is returned if the supplied
 846  * device isn't valid (e.g. it's already been destoryed, the handle isn't
 847  * valid, etc.).
 848  */
 849 static enum sci_status sci_remote_device_destruct(struct isci_remote_device *idev)
 850 {
 851         struct sci_base_state_machine *sm = &idev->sm;
 852         enum sci_remote_device_states state = sm->current_state_id;
 853         struct isci_host *ihost;
 854
 855         if (state != SCI_DEV_STOPPED) {
 856                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
 857                          __func__, state);
 858                 return SCI_FAILURE_INVALID_STATE;
 859         }
 860
 861         ihost = idev->owning_port->owning_controller;
 862         sci_controller_free_remote_node_context(ihost, idev,
 863                                                      idev->rnc.remote_node_index);
 864         idev->rnc.remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
 865         sci_change_state(sm, SCI_DEV_FINAL);
 866
 867         return SCI_SUCCESS;
 868 }
 869
 870 /**
 871  * isci_remote_device_deconstruct() - This function frees an isci_remote_device.
 872  * @ihost: This parameter specifies the isci host object.
 873  * @idev: This parameter specifies the remote device to be freed.
 874  *
 875  */
 876 static void isci_remote_device_deconstruct(struct isci_host *ihost, struct isci_remote_device *idev)
 877 {
 878         dev_dbg(&ihost->pdev->dev,
 879                 "%s: isci_device = %p\n", __func__, idev);
 880
 881         /* There should not be any outstanding io's. All paths to
 882          * here should go through isci_remote_device_nuke_requests.
 883          * If we hit this condition, we will need a way to complete
 884          * io requests in process */
 885         BUG_ON(!list_empty(&idev->reqs_in_process));
 886
 887         sci_remote_device_destruct(idev);
 888         list_del_init(&idev->node);
 889         isci_put_device(idev);
 890 }
 891
 892 static void sci_remote_device_stopped_state_enter(struct sci_base_state_machine *sm)
 893 {
 894         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 895         struct isci_host *ihost = idev->owning_port->owning_controller;
 896         u32 prev_state;
 897
 898         /* If we are entering from the stopping state let the SCI User know that
 899          * the stop operation has completed.
 900          */
 901         prev_state = idev->sm.previous_state_id;
 902         if (prev_state == SCI_DEV_STOPPING)
 903                 isci_remote_device_deconstruct(ihost, idev);
 904
 905         sci_controller_remote_device_stopped(ihost, idev);
 906 }
 907
 908 static void sci_remote_device_starting_state_enter(struct sci_base_state_machine *sm)
 909 {
 910         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 911         struct isci_host *ihost = idev->owning_port->owning_controller;
 912
 913         isci_remote_device_not_ready(ihost, idev,
 914                                      SCIC_REMOTE_DEVICE_NOT_READY_START_REQUESTED);
 915 }
 916
 917 static void sci_remote_device_ready_state_enter(struct sci_base_state_machine *sm)
 918 {
 919         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 920         struct isci_host *ihost = idev->owning_port->owning_controller;
 921         struct domain_device *dev = idev->domain_dev;
 922
 923         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_SATA)) {
 924                 sci_change_state(&idev->sm, SCI_STP_DEV_IDLE);
 925         } else if (dev_is_expander(dev)) {
 926                 sci_change_state(&idev->sm, SCI_SMP_DEV_IDLE);
 927         } else
 928                 isci_remote_device_ready(ihost, idev);
 929 }
 930
 931 static void sci_remote_device_ready_state_exit(struct sci_base_state_machine *sm)
 932 {
 933         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 934         struct domain_device *dev = idev->domain_dev;
 935
 936         if (dev->dev_type == SAS_END_DEV) {
 937                 struct isci_host *ihost = idev->owning_port->owning_controller;
 938
 939                 isci_remote_device_not_ready(ihost, idev,
 940                                              SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED);
 941         }
 942 }
 943
 944 static void sci_remote_device_resetting_state_enter(struct sci_base_state_machine *sm)
 945 {
 946         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 947
 948         sci_remote_node_context_suspend(
 949                 &idev->rnc, SCI_SOFTWARE_SUSPENSION, NULL, NULL);
 950 }
 951
 952 static void sci_remote_device_resetting_state_exit(struct sci_base_state_machine *sm)
 953 {
 954         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 955
 956         sci_remote_node_context_resume(&idev->rnc, NULL, NULL);
 957 }
 958
 959 static void sci_stp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
 960 {
 961         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 962
 963         idev->working_request = NULL;
 964         if (sci_remote_node_context_is_ready(&idev->rnc)) {
 965                 /*
 966                  * Since the RNC is ready, it's alright to finish completion
 967                  * processing (e.g. signal the remote device is ready). */
 968                 sci_stp_remote_device_ready_idle_substate_resume_complete_handler(idev);
 969         } else {
 970                 sci_remote_node_context_resume(&idev->rnc,
 971                         sci_stp_remote_device_ready_idle_substate_resume_complete_handler,
 972                         idev);
 973         }
 974 }
 975
 976 static void sci_stp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
 977 {
 978         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 979         struct isci_host *ihost = idev->owning_port->owning_controller;
 980
 981         BUG_ON(idev->working_request == NULL);
 982
 983         isci_remote_device_not_ready(ihost, idev,
 984                                      SCIC_REMOTE_DEVICE_NOT_READY_SATA_REQUEST_STARTED);
 985 }
 986
 987 static void sci_stp_remote_device_ready_ncq_error_substate_enter(struct sci_base_state_machine *sm)
 988 {
 989         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 990         struct isci_host *ihost = idev->owning_port->owning_controller;
 991
 992         if (idev->not_ready_reason == SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED)
 993                 isci_remote_device_not_ready(ihost, idev,
 994                                              idev->not_ready_reason);
 995 }
 996
 997 static void sci_smp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
 998 {
 999         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1000         struct isci_host *ihost = idev->owning_port->owning_controller;
1001
1002         isci_remote_device_ready(ihost, idev);
1003 }
1004
1005 static void sci_smp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
1006 {
1007         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1008         struct isci_host *ihost = idev->owning_port->owning_controller;
1009
1010         BUG_ON(idev->working_request == NULL);
1011
1012         isci_remote_device_not_ready(ihost, idev,
1013                                      SCIC_REMOTE_DEVICE_NOT_READY_SMP_REQUEST_STARTED);
1014 }
1015
1016 static void sci_smp_remote_device_ready_cmd_substate_exit(struct sci_base_state_machine *sm)
1017 {
1018         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1019
1020         idev->working_request = NULL;
1021 }
1022
1023 static const struct sci_base_state sci_remote_device_state_table[] = {
1024         [SCI_DEV_INITIAL] = {
1025                 .enter_state = sci_remote_device_initial_state_enter,
1026         },
1027         [SCI_DEV_STOPPED] = {
1028                 .enter_state = sci_remote_device_stopped_state_enter,
1029         },
1030         [SCI_DEV_STARTING] = {
1031                 .enter_state = sci_remote_device_starting_state_enter,
1032         },
1033         [SCI_DEV_READY] = {
1034                 .enter_state = sci_remote_device_ready_state_enter,
1035                 .exit_state  = sci_remote_device_ready_state_exit
1036         },
1037         [SCI_STP_DEV_IDLE] = {
1038                 .enter_state = sci_stp_remote_device_ready_idle_substate_enter,
1039         },
1040         [SCI_STP_DEV_CMD] = {
1041                 .enter_state = sci_stp_remote_device_ready_cmd_substate_enter,
1042         },
1043         [SCI_STP_DEV_NCQ] = { },
1044         [SCI_STP_DEV_NCQ_ERROR] = {
1045                 .enter_state = sci_stp_remote_device_ready_ncq_error_substate_enter,
1046         },
1047         [SCI_STP_DEV_ATAPI_ERROR] = { },
1048         [SCI_STP_DEV_AWAIT_RESET] = { },
1049         [SCI_SMP_DEV_IDLE] = {
1050                 .enter_state = sci_smp_remote_device_ready_idle_substate_enter,
1051         },
1052         [SCI_SMP_DEV_CMD] = {
1053                 .enter_state = sci_smp_remote_device_ready_cmd_substate_enter,
1054                 .exit_state  = sci_smp_remote_device_ready_cmd_substate_exit,
1055         },
1056         [SCI_DEV_STOPPING] = { },
1057         [SCI_DEV_FAILED] = { },
1058         [SCI_DEV_RESETTING] = {
1059                 .enter_state = sci_remote_device_resetting_state_enter,
1060                 .exit_state  = sci_remote_device_resetting_state_exit
1061         },
1062         [SCI_DEV_FINAL] = { },
1063 };
1064
1065 /**
1066  * sci_remote_device_construct() - common construction
1067  * @sci_port: SAS/SATA port through which this device is accessed.
1068  * @sci_dev: remote device to construct
1069  *
1070  * This routine just performs benign initialization and does not
1071  * allocate the remote_node_context which is left to
1072  * sci_remote_device_[de]a_construct().  sci_remote_device_destruct()
1073  * frees the remote_node_context(s) for the device.
1074  */
1075 static void sci_remote_device_construct(struct isci_port *iport,
1076                                   struct isci_remote_device *idev)
1077 {
1078         idev->owning_port = iport;
1079         idev->started_request_count = 0;
1080
1081         sci_init_sm(&idev->sm, sci_remote_device_state_table, SCI_DEV_INITIAL);
1082
1083         sci_remote_node_context_construct(&idev->rnc,
1084                                                SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX);
1085 }
1086
1087 /**
1088  * sci_remote_device_da_construct() - construct direct attached device.
1089  *
1090  * The information (e.g. IAF, Signature FIS, etc.) necessary to build
1091  * the device is known to the SCI Core since it is contained in the
1092  * sci_phy object.  Remote node context(s) is/are a global resource
1093  * allocated by this routine, freed by sci_remote_device_destruct().
1094  *
1095  * Returns:
1096  * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
1097  * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
1098  * sata-only controller instance.
1099  * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
1100  */
1101 static enum sci_status sci_remote_device_da_construct(struct isci_port *iport,
1102                                                        struct isci_remote_device *idev)
1103 {
1104         enum sci_status status;
1105         struct sci_port_properties properties;
1106         struct domain_device *dev = idev->domain_dev;
1107
1108         sci_remote_device_construct(iport, idev);
1109
1110         /*
1111          * This information is request to determine how many remote node context
1112          * entries will be needed to store the remote node.
1113          */
1114         idev->is_direct_attached = true;
1115
1116         sci_port_get_properties(iport, &properties);
1117         /* Get accurate port width from port's phy mask for a DA device. */
1118         idev->device_port_width = hweight32(properties.phy_mask);
1119
1120         status = sci_controller_allocate_remote_node_context(iport->owning_controller,
1121                                                                   idev,
1122                                                                   &idev->rnc.remote_node_index);
1123
1124         if (status != SCI_SUCCESS)
1125                 return status;
1126
1127         if (dev->dev_type == SAS_END_DEV || dev->dev_type == SATA_DEV ||
1128             (dev->tproto & SAS_PROTOCOL_STP) || dev_is_expander(dev))
1129                 /* pass */;
1130         else
1131                 return SCI_FAILURE_UNSUPPORTED_PROTOCOL;
1132
1133         idev->connection_rate = sci_port_get_max_allowed_speed(iport);
1134
1135         return SCI_SUCCESS;
1136 }
1137
1138 /**
1139  * sci_remote_device_ea_construct() - construct expander attached device
1140  *
1141  * Remote node context(s) is/are a global resource allocated by this
1142  * routine, freed by sci_remote_device_destruct().
1143  *
1144  * Returns:
1145  * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
1146  * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
1147  * sata-only controller instance.
1148  * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
1149  */
1150 static enum sci_status sci_remote_device_ea_construct(struct isci_port *iport,
1151                                                        struct isci_remote_device *idev)
1152 {
1153         struct domain_device *dev = idev->domain_dev;
1154         enum sci_status status;
1155
1156         sci_remote_device_construct(iport, idev);
1157
1158         status = sci_controller_allocate_remote_node_context(iport->owning_controller,
1159                                                                   idev,
1160                                                                   &idev->rnc.remote_node_index);
1161         if (status != SCI_SUCCESS)
1162                 return status;
1163
1164         if (dev->dev_type == SAS_END_DEV || dev->dev_type == SATA_DEV ||
1165             (dev->tproto & SAS_PROTOCOL_STP) || dev_is_expander(dev))
1166                 /* pass */;
1167         else
1168                 return SCI_FAILURE_UNSUPPORTED_PROTOCOL;
1169
1170         /*
1171          * For SAS-2 the physical link rate is actually a logical link
1172          * rate that incorporates multiplexing.  The SCU doesn't
1173          * incorporate multiplexing and for the purposes of the
1174          * connection the logical link rate is that same as the
1175          * physical.  Furthermore, the SAS-2 and SAS-1.1 fields overlay
1176          * one another, so this code works for both situations. */
1177         idev->connection_rate = min_t(u16, sci_port_get_max_allowed_speed(iport),
1178                                          dev->linkrate);
1179
1180         /* / @todo Should I assign the port width by reading all of the phys on the port? */
1181         idev->device_port_width = 1;
1182
1183         return SCI_SUCCESS;
1184 }
1185
1186 /**
1187  * sci_remote_device_start() - This method will start the supplied remote
1188  *    device.  This method enables normal IO requests to flow through to the
1189  *    remote device.
1190  * @remote_device: This parameter specifies the device to be started.
1191  * @timeout: This parameter specifies the number of milliseconds in which the
1192  *    start operation should complete.
1193  *
1194  * An indication of whether the device was successfully started. SCI_SUCCESS
1195  * This value is returned if the device was successfully started.
1196  * SCI_FAILURE_INVALID_PHY This value is returned if the user attempts to start
1197  * the device when there have been no phys added to it.
1198  */
1199 static enum sci_status sci_remote_device_start(struct isci_remote_device *idev,
1200                                                 u32 timeout)
1201 {
1202         struct sci_base_state_machine *sm = &idev->sm;
1203         enum sci_remote_device_states state = sm->current_state_id;
1204         enum sci_status status;
1205
1206         if (state != SCI_DEV_STOPPED) {
1207                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %d\n",
1208                          __func__, state);
1209                 return SCI_FAILURE_INVALID_STATE;
1210         }
1211
1212         status = sci_remote_node_context_resume(&idev->rnc,
1213                                                      remote_device_resume_done,
1214                                                      idev);
1215         if (status != SCI_SUCCESS)
1216                 return status;
1217
1218         sci_change_state(sm, SCI_DEV_STARTING);
1219
1220         return SCI_SUCCESS;
1221 }
1222
1223 static enum sci_status isci_remote_device_construct(struct isci_port *iport,
1224                                                     struct isci_remote_device *idev)
1225 {
1226         struct isci_host *ihost = iport->isci_host;
1227         struct domain_device *dev = idev->domain_dev;
1228         enum sci_status status;
1229
1230         if (dev->parent && dev_is_expander(dev->parent))
1231                 status = sci_remote_device_ea_construct(iport, idev);
1232         else
1233                 status = sci_remote_device_da_construct(iport, idev);
1234
1235         if (status != SCI_SUCCESS) {
1236                 dev_dbg(&ihost->pdev->dev, "%s: construct failed: %d\n",
1237                         __func__, status);
1238
1239                 return status;
1240         }
1241
1242         /* start the device. */
1243         status = sci_remote_device_start(idev, ISCI_REMOTE_DEVICE_START_TIMEOUT);
1244
1245         if (status != SCI_SUCCESS)
1246                 dev_warn(&ihost->pdev->dev, "remote device start failed: %d\n",
1247                          status);
1248
1249         return status;
1250 }
1251
1252 void isci_remote_device_nuke_requests(struct isci_host *ihost, struct isci_remote_device *idev)
1253 {
1254         DECLARE_COMPLETION_ONSTACK(aborted_task_completion);
1255
1256         dev_dbg(&ihost->pdev->dev,
1257                 "%s: idev = %p\n", __func__, idev);
1258
1259         /* Cleanup all requests pending for this device. */
1260         isci_terminate_pending_requests(ihost, idev);
1261
1262         dev_dbg(&ihost->pdev->dev,
1263                 "%s: idev = %p, done\n", __func__, idev);
1264 }
1265
1266 /**
1267  * This function builds the isci_remote_device when a libsas dev_found message
1268  *    is received.
1269  * @isci_host: This parameter specifies the isci host object.
1270  * @port: This parameter specifies the isci_port conected to this device.
1271  *
1272  * pointer to new isci_remote_device.
1273  */
1274 static struct isci_remote_device *
1275 isci_remote_device_alloc(struct isci_host *ihost, struct isci_port *iport)
1276 {
1277         struct isci_remote_device *idev;
1278         int i;
1279
1280         for (i = 0; i < SCI_MAX_REMOTE_DEVICES; i++) {
1281                 idev = &ihost->devices[i];
1282                 if (!test_and_set_bit(IDEV_ALLOCATED, &idev->flags))
1283                         break;
1284         }
1285
1286         if (i >= SCI_MAX_REMOTE_DEVICES) {
1287                 dev_warn(&ihost->pdev->dev, "%s: failed\n", __func__);
1288                 return NULL;
1289         }
1290
1291         if (WARN_ONCE(!list_empty(&idev->reqs_in_process), "found requests in process\n"))
1292                 return NULL;
1293
1294         if (WARN_ONCE(!list_empty(&idev->node), "found non-idle remote device\n"))
1295                 return NULL;
1296
1297         return idev;
1298 }
1299
1300 void isci_remote_device_release(struct kref *kref)
1301 {
1302         struct isci_remote_device *idev = container_of(kref, typeof(*idev), kref);
1303         struct isci_host *ihost = idev->isci_port->isci_host;
1304
1305         idev->domain_dev = NULL;
1306         idev->isci_port = NULL;
1307         clear_bit(IDEV_START_PENDING, &idev->flags);
1308         clear_bit(IDEV_STOP_PENDING, &idev->flags);
1309         clear_bit(IDEV_IO_READY, &idev->flags);
1310         clear_bit(IDEV_GONE, &idev->flags);
1311         smp_mb__before_clear_bit();
1312         clear_bit(IDEV_ALLOCATED, &idev->flags);
1313         wake_up(&ihost->eventq);
1314 }
1315
1316 /**
1317  * isci_remote_device_stop() - This function is called internally to stop the
1318  *    remote device.
1319  * @isci_host: This parameter specifies the isci host object.
1320  * @isci_device: This parameter specifies the remote device.
1321  *
1322  * The status of the ihost request to stop.
1323  */
1324 enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_remote_device *idev)
1325 {
1326         enum sci_status status;
1327         unsigned long flags;
1328
1329         dev_dbg(&ihost->pdev->dev,
1330                 "%s: isci_device = %p\n", __func__, idev);
1331
1332         spin_lock_irqsave(&ihost->scic_lock, flags);
1333         idev->domain_dev->lldd_dev = NULL; /* disable new lookups */
1334         set_bit(IDEV_GONE, &idev->flags);
1335         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1336
1337         /* Kill all outstanding requests. */
1338         isci_remote_device_nuke_requests(ihost, idev);
1339
1340         set_bit(IDEV_STOP_PENDING, &idev->flags);
1341
1342         spin_lock_irqsave(&ihost->scic_lock, flags);
1343         status = sci_remote_device_stop(idev, 50);
1344         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1345
1346         /* Wait for the stop complete callback. */
1347         if (WARN_ONCE(status != SCI_SUCCESS, "failed to stop device\n"))
1348                 /* nothing to wait for */;
1349         else
1350                 wait_for_device_stop(ihost, idev);
1351
1352         return status;
1353 }
1354
1355 /**
1356  * isci_remote_device_gone() - This function is called by libsas when a domain
1357  *    device is removed.
1358  * @domain_device: This parameter specifies the libsas domain device.
1359  *
1360  */
1361 void isci_remote_device_gone(struct domain_device *dev)
1362 {
1363         struct isci_host *ihost = dev_to_ihost(dev);
1364         struct isci_remote_device *idev = dev->lldd_dev;
1365
1366         dev_dbg(&ihost->pdev->dev,
1367                 "%s: domain_device = %p, isci_device = %p, isci_port = %p\n",
1368                 __func__, dev, idev, idev->isci_port);
1369
1370         isci_remote_device_stop(ihost, idev);
1371 }
1372
1373
1374 /**
1375  * isci_remote_device_found() - This function is called by libsas when a remote
1376  *    device is discovered. A remote device object is created and started. the
1377  *    function then sleeps until the sci core device started message is
1378  *    received.
1379  * @domain_device: This parameter specifies the libsas domain device.
1380  *
1381  * status, zero indicates success.
1382  */
1383 int isci_remote_device_found(struct domain_device *dev)
1384 {
1385         struct isci_host *isci_host = dev_to_ihost(dev);
1386         struct isci_port *isci_port = dev->port->lldd_port;
1387         struct isci_remote_device *isci_device;
1388         enum sci_status status;
1389
1390         dev_dbg(&isci_host->pdev->dev,
1391                 "%s: domain_device = %p\n", __func__, dev);
1392
1393         if (!isci_port)
1394                 return -ENODEV;
1395
1396         isci_device = isci_remote_device_alloc(isci_host, isci_port);
1397         if (!isci_device)
1398                 return -ENODEV;
1399
1400         kref_init(&isci_device->kref);
1401         INIT_LIST_HEAD(&isci_device->node);
1402
1403         spin_lock_irq(&isci_host->scic_lock);
1404         isci_device->domain_dev = dev;
1405         isci_device->isci_port = isci_port;
1406         list_add_tail(&isci_device->node, &isci_port->remote_dev_list);
1407
1408         set_bit(IDEV_START_PENDING, &isci_device->flags);
1409         status = isci_remote_device_construct(isci_port, isci_device);
1410
1411         dev_dbg(&isci_host->pdev->dev,
1412                 "%s: isci_device = %p\n",
1413                 __func__, isci_device);
1414
1415         if (status == SCI_SUCCESS) {
1416                 /* device came up, advertise it to the world */
1417                 dev->lldd_dev = isci_device;
1418         } else
1419                 isci_put_device(isci_device);
1420         spin_unlock_irq(&isci_host->scic_lock);
1421
1422         /* wait for the device ready callback. */
1423         wait_for_device_start(isci_host, isci_device);
1424
1425         return status == SCI_SUCCESS ? 0 : -ENODEV;
1426 }