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 #undef C
  66 #define C(a) (#a)
  67 const char *dev_state_name(enum sci_remote_device_states state)
  68 {
  69         static const char * const strings[] = REMOTE_DEV_STATES;
  70
  71         return strings[state];
  72 }
  73 #undef C
  74
  75 /**
  76  * isci_remote_device_not_ready() - This function is called by the ihost when
  77  *    the remote device is not ready. We mark the isci device as ready (not
  78  *    "ready_for_io") and signal the waiting proccess.
  79  * @isci_host: This parameter specifies the isci host object.
  80  * @isci_device: This parameter specifies the remote device
  81  *
  82  * sci_lock is held on entrance to this function.
  83  */
  84 static void isci_remote_device_not_ready(struct isci_host *ihost,
  85                                   struct isci_remote_device *idev, u32 reason)
  86 {
  87         struct isci_request *ireq;
  88
  89         dev_dbg(&ihost->pdev->dev,
  90                 "%s: isci_device = %p\n", __func__, idev);
  91
  92         switch (reason) {
  93         case SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED:
  94                 set_bit(IDEV_GONE, &idev->flags);
  95                 break;
  96         case SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED:
  97                 set_bit(IDEV_IO_NCQERROR, &idev->flags);
  98
  99                 /* Kill all outstanding requests for the device. */
 100                 list_for_each_entry(ireq, &idev->reqs_in_process, dev_node) {
 101
 102                         dev_dbg(&ihost->pdev->dev,
 103                                 "%s: isci_device = %p request = %p\n",
 104                                 __func__, idev, ireq);
 105
 106                         sci_controller_terminate_request(ihost,
 107                                                           idev,
 108                                                           ireq);
 109                 }
 110                 /* Fall through into the default case... */
 111         default:
 112                 clear_bit(IDEV_IO_READY, &idev->flags);
 113                 break;
 114         }
 115 }
 116
 117 /**
 118  * isci_remote_device_ready() - This function is called by the ihost when the
 119  *    remote device is ready. We mark the isci device as ready and signal the
 120  *    waiting proccess.
 121  * @ihost: our valid isci_host
 122  * @idev: remote device
 123  *
 124  */
 125 static void isci_remote_device_ready(struct isci_host *ihost, struct isci_remote_device *idev)
 126 {
 127         dev_dbg(&ihost->pdev->dev,
 128                 "%s: idev = %p\n", __func__, idev);
 129
 130         clear_bit(IDEV_IO_NCQERROR, &idev->flags);
 131         set_bit(IDEV_IO_READY, &idev->flags);
 132         if (test_and_clear_bit(IDEV_START_PENDING, &idev->flags))
 133                 wake_up(&ihost->eventq);
 134 }
 135
 136 /* called once the remote node context is ready to be freed.
 137  * The remote device can now report that its stop operation is complete. none
 138  */
 139 static void rnc_destruct_done(void *_dev)
 140 {
 141         struct isci_remote_device *idev = _dev;
 142
 143         BUG_ON(idev->started_request_count != 0);
 144         sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 145 }
 146
 147 static enum sci_status sci_remote_device_terminate_requests(struct isci_remote_device *idev)
 148 {
 149         struct isci_host *ihost = idev->owning_port->owning_controller;
 150         enum sci_status status  = SCI_SUCCESS;
 151         u32 i;
 152
 153         for (i = 0; i < SCI_MAX_IO_REQUESTS; i++) {
 154                 struct isci_request *ireq = ihost->reqs[i];
 155                 enum sci_status s;
 156
 157                 if (!test_bit(IREQ_ACTIVE, &ireq->flags) ||
 158                     ireq->target_device != idev)
 159                         continue;
 160
 161                 s = sci_controller_terminate_request(ihost, idev, ireq);
 162                 if (s != SCI_SUCCESS)
 163                         status = s;
 164         }
 165
 166         return status;
 167 }
 168
 169 enum sci_status sci_remote_device_stop(struct isci_remote_device *idev,
 170                                         u32 timeout)
 171 {
 172         struct sci_base_state_machine *sm = &idev->sm;
 173         enum sci_remote_device_states state = sm->current_state_id;
 174
 175         switch (state) {
 176         case SCI_DEV_INITIAL:
 177         case SCI_DEV_FAILED:
 178         case SCI_DEV_FINAL:
 179         default:
 180                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 181                          __func__, dev_state_name(state));
 182                 return SCI_FAILURE_INVALID_STATE;
 183         case SCI_DEV_STOPPED:
 184                 return SCI_SUCCESS;
 185         case SCI_DEV_STARTING:
 186                 /* device not started so there had better be no requests */
 187                 BUG_ON(idev->started_request_count != 0);
 188                 sci_remote_node_context_destruct(&idev->rnc,
 189                                                       rnc_destruct_done, idev);
 190                 /* Transition to the stopping state and wait for the
 191                  * remote node to complete being posted and invalidated.
 192                  */
 193                 sci_change_state(sm, SCI_DEV_STOPPING);
 194                 return SCI_SUCCESS;
 195         case SCI_DEV_READY:
 196         case SCI_STP_DEV_IDLE:
 197         case SCI_STP_DEV_CMD:
 198         case SCI_STP_DEV_NCQ:
 199         case SCI_STP_DEV_NCQ_ERROR:
 200         case SCI_STP_DEV_AWAIT_RESET:
 201         case SCI_SMP_DEV_IDLE:
 202         case SCI_SMP_DEV_CMD:
 203                 sci_change_state(sm, SCI_DEV_STOPPING);
 204                 if (idev->started_request_count == 0) {
 205                         sci_remote_node_context_destruct(&idev->rnc,
 206                                                               rnc_destruct_done, idev);
 207                         return SCI_SUCCESS;
 208                 } else
 209                         return sci_remote_device_terminate_requests(idev);
 210                 break;
 211         case SCI_DEV_STOPPING:
 212                 /* All requests should have been terminated, but if there is an
 213                  * attempt to stop a device already in the stopping state, then
 214                  * try again to terminate.
 215                  */
 216                 return sci_remote_device_terminate_requests(idev);
 217         case SCI_DEV_RESETTING:
 218                 sci_change_state(sm, SCI_DEV_STOPPING);
 219                 return SCI_SUCCESS;
 220         }
 221 }
 222
 223 enum sci_status sci_remote_device_reset(struct isci_remote_device *idev)
 224 {
 225         struct sci_base_state_machine *sm = &idev->sm;
 226         enum sci_remote_device_states state = sm->current_state_id;
 227
 228         switch (state) {
 229         case SCI_DEV_INITIAL:
 230         case SCI_DEV_STOPPED:
 231         case SCI_DEV_STARTING:
 232         case SCI_SMP_DEV_IDLE:
 233         case SCI_SMP_DEV_CMD:
 234         case SCI_DEV_STOPPING:
 235         case SCI_DEV_FAILED:
 236         case SCI_DEV_RESETTING:
 237         case SCI_DEV_FINAL:
 238         default:
 239                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 240                          __func__, dev_state_name(state));
 241                 return SCI_FAILURE_INVALID_STATE;
 242         case SCI_DEV_READY:
 243         case SCI_STP_DEV_IDLE:
 244         case SCI_STP_DEV_CMD:
 245         case SCI_STP_DEV_NCQ:
 246         case SCI_STP_DEV_NCQ_ERROR:
 247         case SCI_STP_DEV_AWAIT_RESET:
 248                 sci_change_state(sm, SCI_DEV_RESETTING);
 249                 return SCI_SUCCESS;
 250         }
 251 }
 252
 253 enum sci_status sci_remote_device_reset_complete(struct isci_remote_device *idev)
 254 {
 255         struct sci_base_state_machine *sm = &idev->sm;
 256         enum sci_remote_device_states state = sm->current_state_id;
 257
 258         if (state != SCI_DEV_RESETTING) {
 259                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 260                          __func__, dev_state_name(state));
 261                 return SCI_FAILURE_INVALID_STATE;
 262         }
 263
 264         sci_change_state(sm, SCI_DEV_READY);
 265         return SCI_SUCCESS;
 266 }
 267
 268 enum sci_status sci_remote_device_suspend(struct isci_remote_device *idev,
 269                                                u32 suspend_type)
 270 {
 271         struct sci_base_state_machine *sm = &idev->sm;
 272         enum sci_remote_device_states state = sm->current_state_id;
 273
 274         if (state != SCI_STP_DEV_CMD) {
 275                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 276                          __func__, dev_state_name(state));
 277                 return SCI_FAILURE_INVALID_STATE;
 278         }
 279
 280         return sci_remote_node_context_suspend(&idev->rnc,
 281                                                     suspend_type, NULL, NULL);
 282 }
 283
 284 enum sci_status sci_remote_device_frame_handler(struct isci_remote_device *idev,
 285                                                      u32 frame_index)
 286 {
 287         struct sci_base_state_machine *sm = &idev->sm;
 288         enum sci_remote_device_states state = sm->current_state_id;
 289         struct isci_host *ihost = idev->owning_port->owning_controller;
 290         enum sci_status status;
 291
 292         switch (state) {
 293         case SCI_DEV_INITIAL:
 294         case SCI_DEV_STOPPED:
 295         case SCI_DEV_STARTING:
 296         case SCI_STP_DEV_IDLE:
 297         case SCI_SMP_DEV_IDLE:
 298         case SCI_DEV_FINAL:
 299         default:
 300                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 301                          __func__, dev_state_name(state));
 302                 /* Return the frame back to the controller */
 303                 sci_controller_release_frame(ihost, frame_index);
 304                 return SCI_FAILURE_INVALID_STATE;
 305         case SCI_DEV_READY:
 306         case SCI_STP_DEV_NCQ_ERROR:
 307         case SCI_STP_DEV_AWAIT_RESET:
 308         case SCI_DEV_STOPPING:
 309         case SCI_DEV_FAILED:
 310         case SCI_DEV_RESETTING: {
 311                 struct isci_request *ireq;
 312                 struct ssp_frame_hdr hdr;
 313                 void *frame_header;
 314                 ssize_t word_cnt;
 315
 316                 status = sci_unsolicited_frame_control_get_header(&ihost->uf_control,
 317                                                                        frame_index,
 318                                                                        &frame_header);
 319                 if (status != SCI_SUCCESS)
 320                         return status;
 321
 322                 word_cnt = sizeof(hdr) / sizeof(u32);
 323                 sci_swab32_cpy(&hdr, frame_header, word_cnt);
 324
 325                 ireq = sci_request_by_tag(ihost, be16_to_cpu(hdr.tag));
 326                 if (ireq && ireq->target_device == idev) {
 327                         /* The IO request is now in charge of releasing the frame */
 328                         status = sci_io_request_frame_handler(ireq, frame_index);
 329                 } else {
 330                         /* We could not map this tag to a valid IO
 331                          * request Just toss the frame and continue
 332                          */
 333                         sci_controller_release_frame(ihost, frame_index);
 334                 }
 335                 break;
 336         }
 337         case SCI_STP_DEV_NCQ: {
 338                 struct dev_to_host_fis *hdr;
 339
 340                 status = sci_unsolicited_frame_control_get_header(&ihost->uf_control,
 341                                                                        frame_index,
 342                                                                        (void **)&hdr);
 343                 if (status != SCI_SUCCESS)
 344                         return status;
 345
 346                 if (hdr->fis_type == FIS_SETDEVBITS &&
 347                     (hdr->status & ATA_ERR)) {
 348                         idev->not_ready_reason = SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED;
 349
 350                         /* TODO Check sactive and complete associated IO if any. */
 351                         sci_change_state(sm, SCI_STP_DEV_NCQ_ERROR);
 352                 } else if (hdr->fis_type == FIS_REGD2H &&
 353                            (hdr->status & ATA_ERR)) {
 354                         /*
 355                          * Some devices return D2H FIS when an NCQ error is detected.
 356                          * Treat this like an SDB error FIS ready reason.
 357                          */
 358                         idev->not_ready_reason = SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED;
 359                         sci_change_state(&idev->sm, SCI_STP_DEV_NCQ_ERROR);
 360                 } else
 361                         status = SCI_FAILURE;
 362
 363                 sci_controller_release_frame(ihost, frame_index);
 364                 break;
 365         }
 366         case SCI_STP_DEV_CMD:
 367         case SCI_SMP_DEV_CMD:
 368                 /* The device does not process any UF received from the hardware while
 369                  * in this state.  All unsolicited frames are forwarded to the io request
 370                  * object.
 371                  */
 372                 status = sci_io_request_frame_handler(idev->working_request, frame_index);
 373                 break;
 374         }
 375
 376         return status;
 377 }
 378
 379 static bool is_remote_device_ready(struct isci_remote_device *idev)
 380 {
 381
 382         struct sci_base_state_machine *sm = &idev->sm;
 383         enum sci_remote_device_states state = sm->current_state_id;
 384
 385         switch (state) {
 386         case SCI_DEV_READY:
 387         case SCI_STP_DEV_IDLE:
 388         case SCI_STP_DEV_CMD:
 389         case SCI_STP_DEV_NCQ:
 390         case SCI_STP_DEV_NCQ_ERROR:
 391         case SCI_STP_DEV_AWAIT_RESET:
 392         case SCI_SMP_DEV_IDLE:
 393         case SCI_SMP_DEV_CMD:
 394                 return true;
 395         default:
 396                 return false;
 397         }
 398 }
 399
 400 /*
 401  * called once the remote node context has transisitioned to a ready
 402  * state (after suspending RX and/or TX due to early D2H fis)
 403  */
 404 static void atapi_remote_device_resume_done(void *_dev)
 405 {
 406         struct isci_remote_device *idev = _dev;
 407         struct isci_request *ireq = idev->working_request;
 408
 409         sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
 410 }
 411
 412 enum sci_status sci_remote_device_event_handler(struct isci_remote_device *idev,
 413                                                      u32 event_code)
 414 {
 415         struct sci_base_state_machine *sm = &idev->sm;
 416         enum sci_remote_device_states state = sm->current_state_id;
 417         enum sci_status status;
 418
 419         switch (scu_get_event_type(event_code)) {
 420         case SCU_EVENT_TYPE_RNC_OPS_MISC:
 421         case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
 422         case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
 423                 status = sci_remote_node_context_event_handler(&idev->rnc, event_code);
 424                 break;
 425         case SCU_EVENT_TYPE_PTX_SCHEDULE_EVENT:
 426                 if (scu_get_event_code(event_code) == SCU_EVENT_IT_NEXUS_TIMEOUT) {
 427                         status = SCI_SUCCESS;
 428
 429                         /* Suspend the associated RNC */
 430                         sci_remote_node_context_suspend(&idev->rnc,
 431                                                               SCI_SOFTWARE_SUSPENSION,
 432                                                               NULL, NULL);
 433
 434                         dev_dbg(scirdev_to_dev(idev),
 435                                 "%s: device: %p event code: %x: %s\n",
 436                                 __func__, idev, event_code,
 437                                 is_remote_device_ready(idev)
 438                                 ? "I_T_Nexus_Timeout event"
 439                                 : "I_T_Nexus_Timeout event in wrong state");
 440
 441                         break;
 442                 }
 443         /* Else, fall through and treat as unhandled... */
 444         default:
 445                 dev_dbg(scirdev_to_dev(idev),
 446                         "%s: device: %p event code: %x: %s\n",
 447                         __func__, idev, event_code,
 448                         is_remote_device_ready(idev)
 449                         ? "unexpected event"
 450                         : "unexpected event in wrong state");
 451                 status = SCI_FAILURE_INVALID_STATE;
 452                 break;
 453         }
 454
 455         if (status != SCI_SUCCESS)
 456                 return status;
 457
 458         if (state == SCI_STP_DEV_ATAPI_ERROR) {
 459                 /* For ATAPI error state resume the RNC right away. */
 460                 if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
 461                     scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX) {
 462                         return sci_remote_node_context_resume(&idev->rnc,
 463                                                               atapi_remote_device_resume_done,
 464                                                               idev);
 465                 }
 466         }
 467
 468         if (state == SCI_STP_DEV_IDLE) {
 469
 470                 /* We pick up suspension events to handle specifically to this
 471                  * state. We resume the RNC right away.
 472                  */
 473                 if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
 474                     scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX)
 475                         status = sci_remote_node_context_resume(&idev->rnc, NULL, NULL);
 476         }
 477
 478         return status;
 479 }
 480
 481 static void sci_remote_device_start_request(struct isci_remote_device *idev,
 482                                                  struct isci_request *ireq,
 483                                                  enum sci_status status)
 484 {
 485         struct isci_port *iport = idev->owning_port;
 486
 487         /* cleanup requests that failed after starting on the port */
 488         if (status != SCI_SUCCESS)
 489                 sci_port_complete_io(iport, idev, ireq);
 490         else {
 491                 kref_get(&idev->kref);
 492                 idev->started_request_count++;
 493         }
 494 }
 495
 496 enum sci_status sci_remote_device_start_io(struct isci_host *ihost,
 497                                                 struct isci_remote_device *idev,
 498                                                 struct isci_request *ireq)
 499 {
 500         struct sci_base_state_machine *sm = &idev->sm;
 501         enum sci_remote_device_states state = sm->current_state_id;
 502         struct isci_port *iport = idev->owning_port;
 503         enum sci_status status;
 504
 505         switch (state) {
 506         case SCI_DEV_INITIAL:
 507         case SCI_DEV_STOPPED:
 508         case SCI_DEV_STARTING:
 509         case SCI_STP_DEV_NCQ_ERROR:
 510         case SCI_DEV_STOPPING:
 511         case SCI_DEV_FAILED:
 512         case SCI_DEV_RESETTING:
 513         case SCI_DEV_FINAL:
 514         default:
 515                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 516                          __func__, dev_state_name(state));
 517                 return SCI_FAILURE_INVALID_STATE;
 518         case SCI_DEV_READY:
 519                 /* attempt to start an io request for this device object. The remote
 520                  * device object will issue the start request for the io and if
 521                  * successful it will start the request for the port object then
 522                  * increment its own request count.
 523                  */
 524                 status = sci_port_start_io(iport, idev, ireq);
 525                 if (status != SCI_SUCCESS)
 526                         return status;
 527
 528                 status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 529                 if (status != SCI_SUCCESS)
 530                         break;
 531
 532                 status = sci_request_start(ireq);
 533                 break;
 534         case SCI_STP_DEV_IDLE: {
 535                 /* handle the start io operation for a sata device that is in
 536                  * the command idle state. - Evalute the type of IO request to
 537                  * be started - If its an NCQ request change to NCQ substate -
 538                  * If its any other command change to the CMD substate
 539                  *
 540                  * If this is a softreset we may want to have a different
 541                  * substate.
 542                  */
 543                 enum sci_remote_device_states new_state;
 544                 struct sas_task *task = isci_request_access_task(ireq);
 545
 546                 status = sci_port_start_io(iport, idev, ireq);
 547                 if (status != SCI_SUCCESS)
 548                         return status;
 549
 550                 status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 551                 if (status != SCI_SUCCESS)
 552                         break;
 553
 554                 status = sci_request_start(ireq);
 555                 if (status != SCI_SUCCESS)
 556                         break;
 557
 558                 if (task->ata_task.use_ncq)
 559                         new_state = SCI_STP_DEV_NCQ;
 560                 else {
 561                         idev->working_request = ireq;
 562                         new_state = SCI_STP_DEV_CMD;
 563                 }
 564                 sci_change_state(sm, new_state);
 565                 break;
 566         }
 567         case SCI_STP_DEV_NCQ: {
 568                 struct sas_task *task = isci_request_access_task(ireq);
 569
 570                 if (task->ata_task.use_ncq) {
 571                         status = sci_port_start_io(iport, idev, ireq);
 572                         if (status != SCI_SUCCESS)
 573                                 return status;
 574
 575                         status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 576                         if (status != SCI_SUCCESS)
 577                                 break;
 578
 579                         status = sci_request_start(ireq);
 580                 } else
 581                         return SCI_FAILURE_INVALID_STATE;
 582                 break;
 583         }
 584         case SCI_STP_DEV_AWAIT_RESET:
 585                 return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
 586         case SCI_SMP_DEV_IDLE:
 587                 status = sci_port_start_io(iport, idev, ireq);
 588                 if (status != SCI_SUCCESS)
 589                         return status;
 590
 591                 status = sci_remote_node_context_start_io(&idev->rnc, ireq);
 592                 if (status != SCI_SUCCESS)
 593                         break;
 594
 595                 status = sci_request_start(ireq);
 596                 if (status != SCI_SUCCESS)
 597                         break;
 598
 599                 idev->working_request = ireq;
 600                 sci_change_state(&idev->sm, SCI_SMP_DEV_CMD);
 601                 break;
 602         case SCI_STP_DEV_CMD:
 603         case SCI_SMP_DEV_CMD:
 604                 /* device is already handling a command it can not accept new commands
 605                  * until this one is complete.
 606                  */
 607                 return SCI_FAILURE_INVALID_STATE;
 608         }
 609
 610         sci_remote_device_start_request(idev, ireq, status);
 611         return status;
 612 }
 613
 614 static enum sci_status common_complete_io(struct isci_port *iport,
 615                                           struct isci_remote_device *idev,
 616                                           struct isci_request *ireq)
 617 {
 618         enum sci_status status;
 619
 620         status = sci_request_complete(ireq);
 621         if (status != SCI_SUCCESS)
 622                 return status;
 623
 624         status = sci_port_complete_io(iport, idev, ireq);
 625         if (status != SCI_SUCCESS)
 626                 return status;
 627
 628         sci_remote_device_decrement_request_count(idev);
 629         return status;
 630 }
 631
 632 enum sci_status sci_remote_device_complete_io(struct isci_host *ihost,
 633                                                    struct isci_remote_device *idev,
 634                                                    struct isci_request *ireq)
 635 {
 636         struct sci_base_state_machine *sm = &idev->sm;
 637         enum sci_remote_device_states state = sm->current_state_id;
 638         struct isci_port *iport = idev->owning_port;
 639         enum sci_status status;
 640
 641         switch (state) {
 642         case SCI_DEV_INITIAL:
 643         case SCI_DEV_STOPPED:
 644         case SCI_DEV_STARTING:
 645         case SCI_STP_DEV_IDLE:
 646         case SCI_SMP_DEV_IDLE:
 647         case SCI_DEV_FAILED:
 648         case SCI_DEV_FINAL:
 649         default:
 650                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 651                          __func__, dev_state_name(state));
 652                 return SCI_FAILURE_INVALID_STATE;
 653         case SCI_DEV_READY:
 654         case SCI_STP_DEV_AWAIT_RESET:
 655         case SCI_DEV_RESETTING:
 656                 status = common_complete_io(iport, idev, ireq);
 657                 break;
 658         case SCI_STP_DEV_CMD:
 659         case SCI_STP_DEV_NCQ:
 660         case SCI_STP_DEV_NCQ_ERROR:
 661         case SCI_STP_DEV_ATAPI_ERROR:
 662                 status = common_complete_io(iport, idev, ireq);
 663                 if (status != SCI_SUCCESS)
 664                         break;
 665
 666                 if (ireq->sci_status == SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) {
 667                         /* This request causes hardware error, device needs to be Lun Reset.
 668                          * So here we force the state machine to IDLE state so the rest IOs
 669                          * can reach RNC state handler, these IOs will be completed by RNC with
 670                          * status of "DEVICE_RESET_REQUIRED", instead of "INVALID STATE".
 671                          */
 672                         sci_change_state(sm, SCI_STP_DEV_AWAIT_RESET);
 673                 } else if (idev->started_request_count == 0)
 674                         sci_change_state(sm, SCI_STP_DEV_IDLE);
 675                 break;
 676         case SCI_SMP_DEV_CMD:
 677                 status = common_complete_io(iport, idev, ireq);
 678                 if (status != SCI_SUCCESS)
 679                         break;
 680                 sci_change_state(sm, SCI_SMP_DEV_IDLE);
 681                 break;
 682         case SCI_DEV_STOPPING:
 683                 status = common_complete_io(iport, idev, ireq);
 684                 if (status != SCI_SUCCESS)
 685                         break;
 686
 687                 if (idev->started_request_count == 0)
 688                         sci_remote_node_context_destruct(&idev->rnc,
 689                                                          rnc_destruct_done,
 690                                                          idev);
 691                 break;
 692         }
 693
 694         if (status != SCI_SUCCESS)
 695                 dev_err(scirdev_to_dev(idev),
 696                         "%s: Port:0x%p Device:0x%p Request:0x%p Status:0x%x "
 697                         "could not complete\n", __func__, iport,
 698                         idev, ireq, status);
 699         else
 700                 isci_put_device(idev);
 701
 702         return status;
 703 }
 704
 705 static void sci_remote_device_continue_request(void *dev)
 706 {
 707         struct isci_remote_device *idev = dev;
 708
 709         /* we need to check if this request is still valid to continue. */
 710         if (idev->working_request)
 711                 sci_controller_continue_io(idev->working_request);
 712 }
 713
 714 enum sci_status sci_remote_device_start_task(struct isci_host *ihost,
 715                                                   struct isci_remote_device *idev,
 716                                                   struct isci_request *ireq)
 717 {
 718         struct sci_base_state_machine *sm = &idev->sm;
 719         enum sci_remote_device_states state = sm->current_state_id;
 720         struct isci_port *iport = idev->owning_port;
 721         enum sci_status status;
 722
 723         switch (state) {
 724         case SCI_DEV_INITIAL:
 725         case SCI_DEV_STOPPED:
 726         case SCI_DEV_STARTING:
 727         case SCI_SMP_DEV_IDLE:
 728         case SCI_SMP_DEV_CMD:
 729         case SCI_DEV_STOPPING:
 730         case SCI_DEV_FAILED:
 731         case SCI_DEV_RESETTING:
 732         case SCI_DEV_FINAL:
 733         default:
 734                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 735                          __func__, dev_state_name(state));
 736                 return SCI_FAILURE_INVALID_STATE;
 737         case SCI_STP_DEV_IDLE:
 738         case SCI_STP_DEV_CMD:
 739         case SCI_STP_DEV_NCQ:
 740         case SCI_STP_DEV_NCQ_ERROR:
 741         case SCI_STP_DEV_AWAIT_RESET:
 742                 status = sci_port_start_io(iport, idev, ireq);
 743                 if (status != SCI_SUCCESS)
 744                         return status;
 745
 746                 status = sci_remote_node_context_start_task(&idev->rnc, ireq);
 747                 if (status != SCI_SUCCESS)
 748                         goto out;
 749
 750                 status = sci_request_start(ireq);
 751                 if (status != SCI_SUCCESS)
 752                         goto out;
 753
 754                 /* Note: If the remote device state is not IDLE this will
 755                  * replace the request that probably resulted in the task
 756                  * management request.
 757                  */
 758                 idev->working_request = ireq;
 759                 sci_change_state(sm, SCI_STP_DEV_CMD);
 760
 761                 /* The remote node context must cleanup the TCi to NCQ mapping
 762                  * table.  The only way to do this correctly is to either write
 763                  * to the TLCR register or to invalidate and repost the RNC. In
 764                  * either case the remote node context state machine will take
 765                  * the correct action when the remote node context is suspended
 766                  * and later resumed.
 767                  */
 768                 sci_remote_node_context_suspend(&idev->rnc,
 769                                 SCI_SOFTWARE_SUSPENSION, NULL, NULL);
 770                 sci_remote_node_context_resume(&idev->rnc,
 771                                 sci_remote_device_continue_request,
 772                                                     idev);
 773
 774         out:
 775                 sci_remote_device_start_request(idev, ireq, status);
 776                 /* We need to let the controller start request handler know that
 777                  * it can't post TC yet. We will provide a callback function to
 778                  * post TC when RNC gets resumed.
 779                  */
 780                 return SCI_FAILURE_RESET_DEVICE_PARTIAL_SUCCESS;
 781         case SCI_DEV_READY:
 782                 status = sci_port_start_io(iport, idev, ireq);
 783                 if (status != SCI_SUCCESS)
 784                         return status;
 785
 786                 status = sci_remote_node_context_start_task(&idev->rnc, ireq);
 787                 if (status != SCI_SUCCESS)
 788                         break;
 789
 790                 status = sci_request_start(ireq);
 791                 break;
 792         }
 793         sci_remote_device_start_request(idev, ireq, status);
 794
 795         return status;
 796 }
 797
 798 void sci_remote_device_post_request(struct isci_remote_device *idev, u32 request)
 799 {
 800         struct isci_port *iport = idev->owning_port;
 801         u32 context;
 802
 803         context = request |
 804                   (ISCI_PEG << SCU_CONTEXT_COMMAND_PROTOCOL_ENGINE_GROUP_SHIFT) |
 805                   (iport->physical_port_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT) |
 806                   idev->rnc.remote_node_index;
 807
 808         sci_controller_post_request(iport->owning_controller, context);
 809 }
 810
 811 /* called once the remote node context has transisitioned to a
 812  * ready state.  This is the indication that the remote device object can also
 813  * transition to ready.
 814  */
 815 static void remote_device_resume_done(void *_dev)
 816 {
 817         struct isci_remote_device *idev = _dev;
 818
 819         if (is_remote_device_ready(idev))
 820                 return;
 821
 822         /* go 'ready' if we are not already in a ready state */
 823         sci_change_state(&idev->sm, SCI_DEV_READY);
 824 }
 825
 826 static void sci_stp_remote_device_ready_idle_substate_resume_complete_handler(void *_dev)
 827 {
 828         struct isci_remote_device *idev = _dev;
 829         struct isci_host *ihost = idev->owning_port->owning_controller;
 830
 831         /* For NCQ operation we do not issue a isci_remote_device_not_ready().
 832          * As a result, avoid sending the ready notification.
 833          */
 834         if (idev->sm.previous_state_id != SCI_STP_DEV_NCQ)
 835                 isci_remote_device_ready(ihost, idev);
 836 }
 837
 838 static void sci_remote_device_initial_state_enter(struct sci_base_state_machine *sm)
 839 {
 840         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 841
 842         /* Initial state is a transitional state to the stopped state */
 843         sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 844 }
 845
 846 /**
 847  * sci_remote_device_destruct() - free remote node context and destruct
 848  * @remote_device: This parameter specifies the remote device to be destructed.
 849  *
 850  * Remote device objects are a limited resource.  As such, they must be
 851  * protected.  Thus calls to construct and destruct are mutually exclusive and
 852  * non-reentrant. The return value shall indicate if the device was
 853  * successfully destructed or if some failure occurred. enum sci_status This value
 854  * is returned if the device is successfully destructed.
 855  * SCI_FAILURE_INVALID_REMOTE_DEVICE This value is returned if the supplied
 856  * device isn't valid (e.g. it's already been destoryed, the handle isn't
 857  * valid, etc.).
 858  */
 859 static enum sci_status sci_remote_device_destruct(struct isci_remote_device *idev)
 860 {
 861         struct sci_base_state_machine *sm = &idev->sm;
 862         enum sci_remote_device_states state = sm->current_state_id;
 863         struct isci_host *ihost;
 864
 865         if (state != SCI_DEV_STOPPED) {
 866                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
 867                          __func__, dev_state_name(state));
 868                 return SCI_FAILURE_INVALID_STATE;
 869         }
 870
 871         ihost = idev->owning_port->owning_controller;
 872         sci_controller_free_remote_node_context(ihost, idev,
 873                                                      idev->rnc.remote_node_index);
 874         idev->rnc.remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
 875         sci_change_state(sm, SCI_DEV_FINAL);
 876
 877         return SCI_SUCCESS;
 878 }
 879
 880 /**
 881  * isci_remote_device_deconstruct() - This function frees an isci_remote_device.
 882  * @ihost: This parameter specifies the isci host object.
 883  * @idev: This parameter specifies the remote device to be freed.
 884  *
 885  */
 886 static void isci_remote_device_deconstruct(struct isci_host *ihost, struct isci_remote_device *idev)
 887 {
 888         dev_dbg(&ihost->pdev->dev,
 889                 "%s: isci_device = %p\n", __func__, idev);
 890
 891         /* There should not be any outstanding io's. All paths to
 892          * here should go through isci_remote_device_nuke_requests.
 893          * If we hit this condition, we will need a way to complete
 894          * io requests in process */
 895         BUG_ON(!list_empty(&idev->reqs_in_process));
 896
 897         sci_remote_device_destruct(idev);
 898         list_del_init(&idev->node);
 899         isci_put_device(idev);
 900 }
 901
 902 static void sci_remote_device_stopped_state_enter(struct sci_base_state_machine *sm)
 903 {
 904         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 905         struct isci_host *ihost = idev->owning_port->owning_controller;
 906         u32 prev_state;
 907
 908         /* If we are entering from the stopping state let the SCI User know that
 909          * the stop operation has completed.
 910          */
 911         prev_state = idev->sm.previous_state_id;
 912         if (prev_state == SCI_DEV_STOPPING)
 913                 isci_remote_device_deconstruct(ihost, idev);
 914
 915         sci_controller_remote_device_stopped(ihost, idev);
 916 }
 917
 918 static void sci_remote_device_starting_state_enter(struct sci_base_state_machine *sm)
 919 {
 920         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 921         struct isci_host *ihost = idev->owning_port->owning_controller;
 922
 923         isci_remote_device_not_ready(ihost, idev,
 924                                      SCIC_REMOTE_DEVICE_NOT_READY_START_REQUESTED);
 925 }
 926
 927 static void sci_remote_device_ready_state_enter(struct sci_base_state_machine *sm)
 928 {
 929         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 930         struct isci_host *ihost = idev->owning_port->owning_controller;
 931         struct domain_device *dev = idev->domain_dev;
 932
 933         if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_SATA)) {
 934                 sci_change_state(&idev->sm, SCI_STP_DEV_IDLE);
 935         } else if (dev_is_expander(dev)) {
 936                 sci_change_state(&idev->sm, SCI_SMP_DEV_IDLE);
 937         } else
 938                 isci_remote_device_ready(ihost, idev);
 939 }
 940
 941 static void sci_remote_device_ready_state_exit(struct sci_base_state_machine *sm)
 942 {
 943         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 944         struct domain_device *dev = idev->domain_dev;
 945
 946         if (dev->dev_type == SAS_END_DEV) {
 947                 struct isci_host *ihost = idev->owning_port->owning_controller;
 948
 949                 isci_remote_device_not_ready(ihost, idev,
 950                                              SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED);
 951         }
 952 }
 953
 954 static void sci_remote_device_resetting_state_enter(struct sci_base_state_machine *sm)
 955 {
 956         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 957
 958         sci_remote_node_context_suspend(
 959                 &idev->rnc, SCI_SOFTWARE_SUSPENSION, NULL, NULL);
 960 }
 961
 962 static void sci_remote_device_resetting_state_exit(struct sci_base_state_machine *sm)
 963 {
 964         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 965
 966         sci_remote_node_context_resume(&idev->rnc, NULL, NULL);
 967 }
 968
 969 static void sci_stp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
 970 {
 971         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 972
 973         idev->working_request = NULL;
 974         if (sci_remote_node_context_is_ready(&idev->rnc)) {
 975                 /*
 976                  * Since the RNC is ready, it's alright to finish completion
 977                  * processing (e.g. signal the remote device is ready). */
 978                 sci_stp_remote_device_ready_idle_substate_resume_complete_handler(idev);
 979         } else {
 980                 sci_remote_node_context_resume(&idev->rnc,
 981                         sci_stp_remote_device_ready_idle_substate_resume_complete_handler,
 982                         idev);
 983         }
 984 }
 985
 986 static void sci_stp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
 987 {
 988         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
 989         struct isci_host *ihost = idev->owning_port->owning_controller;
 990
 991         BUG_ON(idev->working_request == NULL);
 992
 993         isci_remote_device_not_ready(ihost, idev,
 994                                      SCIC_REMOTE_DEVICE_NOT_READY_SATA_REQUEST_STARTED);
 995 }
 996
 997 static void sci_stp_remote_device_ready_ncq_error_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         if (idev->not_ready_reason == SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED)
1003                 isci_remote_device_not_ready(ihost, idev,
1004                                              idev->not_ready_reason);
1005 }
1006
1007 static void sci_smp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
1008 {
1009         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1010         struct isci_host *ihost = idev->owning_port->owning_controller;
1011
1012         isci_remote_device_ready(ihost, idev);
1013 }
1014
1015 static void sci_smp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
1016 {
1017         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1018         struct isci_host *ihost = idev->owning_port->owning_controller;
1019
1020         BUG_ON(idev->working_request == NULL);
1021
1022         isci_remote_device_not_ready(ihost, idev,
1023                                      SCIC_REMOTE_DEVICE_NOT_READY_SMP_REQUEST_STARTED);
1024 }
1025
1026 static void sci_smp_remote_device_ready_cmd_substate_exit(struct sci_base_state_machine *sm)
1027 {
1028         struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
1029
1030         idev->working_request = NULL;
1031 }
1032
1033 static const struct sci_base_state sci_remote_device_state_table[] = {
1034         [SCI_DEV_INITIAL] = {
1035                 .enter_state = sci_remote_device_initial_state_enter,
1036         },
1037         [SCI_DEV_STOPPED] = {
1038                 .enter_state = sci_remote_device_stopped_state_enter,
1039         },
1040         [SCI_DEV_STARTING] = {
1041                 .enter_state = sci_remote_device_starting_state_enter,
1042         },
1043         [SCI_DEV_READY] = {
1044                 .enter_state = sci_remote_device_ready_state_enter,
1045                 .exit_state  = sci_remote_device_ready_state_exit
1046         },
1047         [SCI_STP_DEV_IDLE] = {
1048                 .enter_state = sci_stp_remote_device_ready_idle_substate_enter,
1049         },
1050         [SCI_STP_DEV_CMD] = {
1051                 .enter_state = sci_stp_remote_device_ready_cmd_substate_enter,
1052         },
1053         [SCI_STP_DEV_NCQ] = { },
1054         [SCI_STP_DEV_NCQ_ERROR] = {
1055                 .enter_state = sci_stp_remote_device_ready_ncq_error_substate_enter,
1056         },
1057         [SCI_STP_DEV_ATAPI_ERROR] = { },
1058         [SCI_STP_DEV_AWAIT_RESET] = { },
1059         [SCI_SMP_DEV_IDLE] = {
1060                 .enter_state = sci_smp_remote_device_ready_idle_substate_enter,
1061         },
1062         [SCI_SMP_DEV_CMD] = {
1063                 .enter_state = sci_smp_remote_device_ready_cmd_substate_enter,
1064                 .exit_state  = sci_smp_remote_device_ready_cmd_substate_exit,
1065         },
1066         [SCI_DEV_STOPPING] = { },
1067         [SCI_DEV_FAILED] = { },
1068         [SCI_DEV_RESETTING] = {
1069                 .enter_state = sci_remote_device_resetting_state_enter,
1070                 .exit_state  = sci_remote_device_resetting_state_exit
1071         },
1072         [SCI_DEV_FINAL] = { },
1073 };
1074
1075 /**
1076  * sci_remote_device_construct() - common construction
1077  * @sci_port: SAS/SATA port through which this device is accessed.
1078  * @sci_dev: remote device to construct
1079  *
1080  * This routine just performs benign initialization and does not
1081  * allocate the remote_node_context which is left to
1082  * sci_remote_device_[de]a_construct().  sci_remote_device_destruct()
1083  * frees the remote_node_context(s) for the device.
1084  */
1085 static void sci_remote_device_construct(struct isci_port *iport,
1086                                   struct isci_remote_device *idev)
1087 {
1088         idev->owning_port = iport;
1089         idev->started_request_count = 0;
1090
1091         sci_init_sm(&idev->sm, sci_remote_device_state_table, SCI_DEV_INITIAL);
1092
1093         sci_remote_node_context_construct(&idev->rnc,
1094                                                SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX);
1095 }
1096
1097 /**
1098  * sci_remote_device_da_construct() - construct direct attached device.
1099  *
1100  * The information (e.g. IAF, Signature FIS, etc.) necessary to build
1101  * the device is known to the SCI Core since it is contained in the
1102  * sci_phy object.  Remote node context(s) is/are a global resource
1103  * allocated by this routine, freed by sci_remote_device_destruct().
1104  *
1105  * Returns:
1106  * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
1107  * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
1108  * sata-only controller instance.
1109  * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
1110  */
1111 static enum sci_status sci_remote_device_da_construct(struct isci_port *iport,
1112                                                        struct isci_remote_device *idev)
1113 {
1114         enum sci_status status;
1115         struct sci_port_properties properties;
1116         struct domain_device *dev = idev->domain_dev;
1117
1118         sci_remote_device_construct(iport, idev);
1119
1120         /*
1121          * This information is request to determine how many remote node context
1122          * entries will be needed to store the remote node.
1123          */
1124         idev->is_direct_attached = true;
1125
1126         sci_port_get_properties(iport, &properties);
1127         /* Get accurate port width from port's phy mask for a DA device. */
1128         idev->device_port_width = hweight32(properties.phy_mask);
1129
1130         status = sci_controller_allocate_remote_node_context(iport->owning_controller,
1131                                                                   idev,
1132                                                                   &idev->rnc.remote_node_index);
1133
1134         if (status != SCI_SUCCESS)
1135                 return status;
1136
1137         if (dev->dev_type == SAS_END_DEV || dev->dev_type == SATA_DEV ||
1138             (dev->tproto & SAS_PROTOCOL_STP) || dev_is_expander(dev))
1139                 /* pass */;
1140         else
1141                 return SCI_FAILURE_UNSUPPORTED_PROTOCOL;
1142
1143         idev->connection_rate = sci_port_get_max_allowed_speed(iport);
1144
1145         return SCI_SUCCESS;
1146 }
1147
1148 /**
1149  * sci_remote_device_ea_construct() - construct expander attached device
1150  *
1151  * Remote node context(s) is/are a global resource allocated by this
1152  * routine, freed by sci_remote_device_destruct().
1153  *
1154  * Returns:
1155  * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
1156  * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
1157  * sata-only controller instance.
1158  * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
1159  */
1160 static enum sci_status sci_remote_device_ea_construct(struct isci_port *iport,
1161                                                        struct isci_remote_device *idev)
1162 {
1163         struct domain_device *dev = idev->domain_dev;
1164         enum sci_status status;
1165
1166         sci_remote_device_construct(iport, idev);
1167
1168         status = sci_controller_allocate_remote_node_context(iport->owning_controller,
1169                                                                   idev,
1170                                                                   &idev->rnc.remote_node_index);
1171         if (status != SCI_SUCCESS)
1172                 return status;
1173
1174         if (dev->dev_type == SAS_END_DEV || dev->dev_type == SATA_DEV ||
1175             (dev->tproto & SAS_PROTOCOL_STP) || dev_is_expander(dev))
1176                 /* pass */;
1177         else
1178                 return SCI_FAILURE_UNSUPPORTED_PROTOCOL;
1179
1180         /*
1181          * For SAS-2 the physical link rate is actually a logical link
1182          * rate that incorporates multiplexing.  The SCU doesn't
1183          * incorporate multiplexing and for the purposes of the
1184          * connection the logical link rate is that same as the
1185          * physical.  Furthermore, the SAS-2 and SAS-1.1 fields overlay
1186          * one another, so this code works for both situations. */
1187         idev->connection_rate = min_t(u16, sci_port_get_max_allowed_speed(iport),
1188                                          dev->linkrate);
1189
1190         /* / @todo Should I assign the port width by reading all of the phys on the port? */
1191         idev->device_port_width = 1;
1192
1193         return SCI_SUCCESS;
1194 }
1195
1196 /**
1197  * sci_remote_device_start() - This method will start the supplied remote
1198  *    device.  This method enables normal IO requests to flow through to the
1199  *    remote device.
1200  * @remote_device: This parameter specifies the device to be started.
1201  * @timeout: This parameter specifies the number of milliseconds in which the
1202  *    start operation should complete.
1203  *
1204  * An indication of whether the device was successfully started. SCI_SUCCESS
1205  * This value is returned if the device was successfully started.
1206  * SCI_FAILURE_INVALID_PHY This value is returned if the user attempts to start
1207  * the device when there have been no phys added to it.
1208  */
1209 static enum sci_status sci_remote_device_start(struct isci_remote_device *idev,
1210                                                 u32 timeout)
1211 {
1212         struct sci_base_state_machine *sm = &idev->sm;
1213         enum sci_remote_device_states state = sm->current_state_id;
1214         enum sci_status status;
1215
1216         if (state != SCI_DEV_STOPPED) {
1217                 dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
1218                          __func__, dev_state_name(state));
1219                 return SCI_FAILURE_INVALID_STATE;
1220         }
1221
1222         status = sci_remote_node_context_resume(&idev->rnc,
1223                                                      remote_device_resume_done,
1224                                                      idev);
1225         if (status != SCI_SUCCESS)
1226                 return status;
1227
1228         sci_change_state(sm, SCI_DEV_STARTING);
1229
1230         return SCI_SUCCESS;
1231 }
1232
1233 static enum sci_status isci_remote_device_construct(struct isci_port *iport,
1234                                                     struct isci_remote_device *idev)
1235 {
1236         struct isci_host *ihost = iport->isci_host;
1237         struct domain_device *dev = idev->domain_dev;
1238         enum sci_status status;
1239
1240         if (dev->parent && dev_is_expander(dev->parent))
1241                 status = sci_remote_device_ea_construct(iport, idev);
1242         else
1243                 status = sci_remote_device_da_construct(iport, idev);
1244
1245         if (status != SCI_SUCCESS) {
1246                 dev_dbg(&ihost->pdev->dev, "%s: construct failed: %d\n",
1247                         __func__, status);
1248
1249                 return status;
1250         }
1251
1252         /* start the device. */
1253         status = sci_remote_device_start(idev, ISCI_REMOTE_DEVICE_START_TIMEOUT);
1254
1255         if (status != SCI_SUCCESS)
1256                 dev_warn(&ihost->pdev->dev, "remote device start failed: %d\n",
1257                          status);
1258
1259         return status;
1260 }
1261
1262 void isci_remote_device_nuke_requests(struct isci_host *ihost, struct isci_remote_device *idev)
1263 {
1264         DECLARE_COMPLETION_ONSTACK(aborted_task_completion);
1265
1266         dev_dbg(&ihost->pdev->dev,
1267                 "%s: idev = %p\n", __func__, idev);
1268
1269         /* Cleanup all requests pending for this device. */
1270         isci_terminate_pending_requests(ihost, idev);
1271
1272         dev_dbg(&ihost->pdev->dev,
1273                 "%s: idev = %p, done\n", __func__, idev);
1274 }
1275
1276 /**
1277  * This function builds the isci_remote_device when a libsas dev_found message
1278  *    is received.
1279  * @isci_host: This parameter specifies the isci host object.
1280  * @port: This parameter specifies the isci_port conected to this device.
1281  *
1282  * pointer to new isci_remote_device.
1283  */
1284 static struct isci_remote_device *
1285 isci_remote_device_alloc(struct isci_host *ihost, struct isci_port *iport)
1286 {
1287         struct isci_remote_device *idev;
1288         int i;
1289
1290         for (i = 0; i < SCI_MAX_REMOTE_DEVICES; i++) {
1291                 idev = &ihost->devices[i];
1292                 if (!test_and_set_bit(IDEV_ALLOCATED, &idev->flags))
1293                         break;
1294         }
1295
1296         if (i >= SCI_MAX_REMOTE_DEVICES) {
1297                 dev_warn(&ihost->pdev->dev, "%s: failed\n", __func__);
1298                 return NULL;
1299         }
1300
1301         if (WARN_ONCE(!list_empty(&idev->reqs_in_process), "found requests in process\n"))
1302                 return NULL;
1303
1304         if (WARN_ONCE(!list_empty(&idev->node), "found non-idle remote device\n"))
1305                 return NULL;
1306
1307         return idev;
1308 }
1309
1310 void isci_remote_device_release(struct kref *kref)
1311 {
1312         struct isci_remote_device *idev = container_of(kref, typeof(*idev), kref);
1313         struct isci_host *ihost = idev->isci_port->isci_host;
1314
1315         idev->domain_dev = NULL;
1316         idev->isci_port = NULL;
1317         clear_bit(IDEV_START_PENDING, &idev->flags);
1318         clear_bit(IDEV_STOP_PENDING, &idev->flags);
1319         clear_bit(IDEV_IO_READY, &idev->flags);
1320         clear_bit(IDEV_GONE, &idev->flags);
1321         smp_mb__before_clear_bit();
1322         clear_bit(IDEV_ALLOCATED, &idev->flags);
1323         wake_up(&ihost->eventq);
1324 }
1325
1326 /**
1327  * isci_remote_device_stop() - This function is called internally to stop the
1328  *    remote device.
1329  * @isci_host: This parameter specifies the isci host object.
1330  * @isci_device: This parameter specifies the remote device.
1331  *
1332  * The status of the ihost request to stop.
1333  */
1334 enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_remote_device *idev)
1335 {
1336         enum sci_status status;
1337         unsigned long flags;
1338
1339         dev_dbg(&ihost->pdev->dev,
1340                 "%s: isci_device = %p\n", __func__, idev);
1341
1342         spin_lock_irqsave(&ihost->scic_lock, flags);
1343         idev->domain_dev->lldd_dev = NULL; /* disable new lookups */
1344         set_bit(IDEV_GONE, &idev->flags);
1345         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1346
1347         /* Kill all outstanding requests. */
1348         isci_remote_device_nuke_requests(ihost, idev);
1349
1350         set_bit(IDEV_STOP_PENDING, &idev->flags);
1351
1352         spin_lock_irqsave(&ihost->scic_lock, flags);
1353         status = sci_remote_device_stop(idev, 50);
1354         spin_unlock_irqrestore(&ihost->scic_lock, flags);
1355
1356         /* Wait for the stop complete callback. */
1357         if (WARN_ONCE(status != SCI_SUCCESS, "failed to stop device\n"))
1358                 /* nothing to wait for */;
1359         else
1360                 wait_for_device_stop(ihost, idev);
1361
1362         return status;
1363 }
1364
1365 /**
1366  * isci_remote_device_gone() - This function is called by libsas when a domain
1367  *    device is removed.
1368  * @domain_device: This parameter specifies the libsas domain device.
1369  *
1370  */
1371 void isci_remote_device_gone(struct domain_device *dev)
1372 {
1373         struct isci_host *ihost = dev_to_ihost(dev);
1374         struct isci_remote_device *idev = dev->lldd_dev;
1375
1376         dev_dbg(&ihost->pdev->dev,
1377                 "%s: domain_device = %p, isci_device = %p, isci_port = %p\n",
1378                 __func__, dev, idev, idev->isci_port);
1379
1380         isci_remote_device_stop(ihost, idev);
1381 }
1382
1383
1384 /**
1385  * isci_remote_device_found() - This function is called by libsas when a remote
1386  *    device is discovered. A remote device object is created and started. the
1387  *    function then sleeps until the sci core device started message is
1388  *    received.
1389  * @domain_device: This parameter specifies the libsas domain device.
1390  *
1391  * status, zero indicates success.
1392  */
1393 int isci_remote_device_found(struct domain_device *dev)
1394 {
1395         struct isci_host *isci_host = dev_to_ihost(dev);
1396         struct isci_port *isci_port = dev->port->lldd_port;
1397         struct isci_remote_device *isci_device;
1398         enum sci_status status;
1399
1400         dev_dbg(&isci_host->pdev->dev,
1401                 "%s: domain_device = %p\n", __func__, dev);
1402
1403         if (!isci_port)
1404                 return -ENODEV;
1405
1406         isci_device = isci_remote_device_alloc(isci_host, isci_port);
1407         if (!isci_device)
1408                 return -ENODEV;
1409
1410         kref_init(&isci_device->kref);
1411         INIT_LIST_HEAD(&isci_device->node);
1412
1413         spin_lock_irq(&isci_host->scic_lock);
1414         isci_device->domain_dev = dev;
1415         isci_device->isci_port = isci_port;
1416         list_add_tail(&isci_device->node, &isci_port->remote_dev_list);
1417
1418         set_bit(IDEV_START_PENDING, &isci_device->flags);
1419         status = isci_remote_device_construct(isci_port, isci_device);
1420
1421         dev_dbg(&isci_host->pdev->dev,
1422                 "%s: isci_device = %p\n",
1423                 __func__, isci_device);
1424
1425         if (status == SCI_SUCCESS) {
1426                 /* device came up, advertise it to the world */
1427                 dev->lldd_dev = isci_device;
1428         } else
1429                 isci_put_device(isci_device);
1430         spin_unlock_irq(&isci_host->scic_lock);
1431
1432         /* wait for the device ready callback. */
1433         wait_for_device_start(isci_host, isci_device);
1434
1435         return status == SCI_SUCCESS ? 0 : -ENODEV;
1436 }