drivers/scsi/libsas/sas_scsi_host.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Serial Attached SCSI (SAS) class SCSI Host glue.
   4  *
   5  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
   6  * Copyright (C) 2005 Luben Tuikov <[email protected]>
   7  */
   8
   9 #include <linux/kthread.h>
  10 #include <linux/firmware.h>
  11 #include <linux/export.h>
  12 #include <linux/ctype.h>
  13 #include <linux/kernel.h>
  14
  15 #include "sas_internal.h"
  16
  17 #include <scsi/scsi_host.h>
  18 #include <scsi/scsi_device.h>
  19 #include <scsi/scsi_tcq.h>
  20 #include <scsi/scsi.h>
  21 #include <scsi/scsi_eh.h>
  22 #include <scsi/scsi_transport.h>
  23 #include <scsi/scsi_transport_sas.h>
  24 #include <scsi/sas_ata.h>
  25 #include "scsi_sas_internal.h"
  26 #include "scsi_transport_api.h"
  27 #include "scsi_priv.h"
  28
  29 #include <linux/err.h>
  30 #include <linux/blkdev.h>
  31 #include <linux/freezer.h>
  32 #include <linux/gfp.h>
  33 #include <linux/scatterlist.h>
  34 #include <linux/libata.h>
  35
  36 /* record final status and free the task */
  37 static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
  38 {
  39         struct task_status_struct *ts = &task->task_status;
  40         enum scsi_host_status hs = DID_OK;
  41         enum exec_status stat = SAS_SAM_STAT_GOOD;
  42
  43         if (ts->resp == SAS_TASK_UNDELIVERED) {
  44                 /* transport error */
  45                 hs = DID_NO_CONNECT;
  46         } else { /* ts->resp == SAS_TASK_COMPLETE */
  47                 /* task delivered, what happened afterwards? */
  48                 switch (ts->stat) {
  49                 case SAS_DEV_NO_RESPONSE:
  50                 case SAS_INTERRUPTED:
  51                 case SAS_PHY_DOWN:
  52                 case SAS_NAK_R_ERR:
  53                 case SAS_OPEN_TO:
  54                         hs = DID_NO_CONNECT;
  55                         break;
  56                 case SAS_DATA_UNDERRUN:
  57                         scsi_set_resid(sc, ts->residual);
  58                         if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
  59                                 hs = DID_ERROR;
  60                         break;
  61                 case SAS_DATA_OVERRUN:
  62                         hs = DID_ERROR;
  63                         break;
  64                 case SAS_QUEUE_FULL:
  65                         hs = DID_SOFT_ERROR; /* retry */
  66                         break;
  67                 case SAS_DEVICE_UNKNOWN:
  68                         hs = DID_BAD_TARGET;
  69                         break;
  70                 case SAS_SG_ERR:
  71                         hs = DID_PARITY;
  72                         break;
  73                 case SAS_OPEN_REJECT:
  74                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
  75                                 hs = DID_SOFT_ERROR; /* retry */
  76                         else
  77                                 hs = DID_ERROR;
  78                         break;
  79                 case SAS_PROTO_RESPONSE:
  80                         pr_notice("LLDD:%s sent SAS_PROTO_RESP for an SSP task; please report this\n",
  81                                   task->dev->port->ha->sas_ha_name);
  82                         break;
  83                 case SAS_ABORTED_TASK:
  84                         hs = DID_ABORT;
  85                         break;
  86                 case SAS_SAM_STAT_CHECK_CONDITION:
  87                         memcpy(sc->sense_buffer, ts->buf,
  88                                min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
  89                         stat = SAS_SAM_STAT_CHECK_CONDITION;
  90                         break;
  91                 default:
  92                         stat = ts->stat;
  93                         break;
  94                 }
  95         }
  96
  97         sc->result = (hs << 16) | stat;
  98         ASSIGN_SAS_TASK(sc, NULL);
  99         sas_free_task(task);
 100 }
 101
 102 static void sas_scsi_task_done(struct sas_task *task)
 103 {
 104         struct scsi_cmnd *sc = task->uldd_task;
 105         struct domain_device *dev = task->dev;
 106         struct sas_ha_struct *ha = dev->port->ha;
 107         unsigned long flags;
 108
 109         spin_lock_irqsave(&dev->done_lock, flags);
 110         if (test_bit(SAS_HA_FROZEN, &ha->state))
 111                 task = NULL;
 112         else
 113                 ASSIGN_SAS_TASK(sc, NULL);
 114         spin_unlock_irqrestore(&dev->done_lock, flags);
 115
 116         if (unlikely(!task)) {
 117                 /* task will be completed by the error handler */
 118                 pr_debug("task done but aborted\n");
 119                 return;
 120         }
 121
 122         if (unlikely(!sc)) {
 123                 pr_debug("task_done called with non existing SCSI cmnd!\n");
 124                 sas_free_task(task);
 125                 return;
 126         }
 127
 128         sas_end_task(sc, task);
 129         scsi_done(sc);
 130 }
 131
 132 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 133                                                struct domain_device *dev,
 134                                                gfp_t gfp_flags)
 135 {
 136         struct sas_task *task = sas_alloc_task(gfp_flags);
 137         struct scsi_lun lun;
 138
 139         if (!task)
 140                 return NULL;
 141
 142         task->uldd_task = cmd;
 143         ASSIGN_SAS_TASK(cmd, task);
 144
 145         task->dev = dev;
 146         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
 147
 148         task->ssp_task.retry_count = 1;
 149         int_to_scsilun(cmd->device->lun, &lun);
 150         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
 151         task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
 152         task->ssp_task.cmd = cmd;
 153
 154         task->scatter = scsi_sglist(cmd);
 155         task->num_scatter = scsi_sg_count(cmd);
 156         task->total_xfer_len = scsi_bufflen(cmd);
 157         task->data_dir = cmd->sc_data_direction;
 158
 159         task->task_done = sas_scsi_task_done;
 160
 161         return task;
 162 }
 163
 164 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 165 {
 166         struct sas_internal *i = to_sas_internal(host->transportt);
 167         struct domain_device *dev = cmd_to_domain_dev(cmd);
 168         struct sas_task *task;
 169         int res = 0;
 170
 171         /* If the device fell off, no sense in issuing commands */
 172         if (test_bit(SAS_DEV_GONE, &dev->state)) {
 173                 cmd->result = DID_BAD_TARGET << 16;
 174                 goto out_done;
 175         }
 176
 177         if (dev_is_sata(dev)) {
 178                 spin_lock_irq(dev->sata_dev.ap->lock);
 179                 res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
 180                 spin_unlock_irq(dev->sata_dev.ap->lock);
 181                 return res;
 182         }
 183
 184         task = sas_create_task(cmd, dev, GFP_ATOMIC);
 185         if (!task)
 186                 return SCSI_MLQUEUE_HOST_BUSY;
 187
 188         res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
 189         if (res)
 190                 goto out_free_task;
 191         return 0;
 192
 193 out_free_task:
 194         pr_debug("lldd_execute_task returned: %d\n", res);
 195         ASSIGN_SAS_TASK(cmd, NULL);
 196         sas_free_task(task);
 197         if (res == -SAS_QUEUE_FULL)
 198                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
 199         else
 200                 cmd->result = DID_ERROR << 16;
 201 out_done:
 202         scsi_done(cmd);
 203         return 0;
 204 }
 205 EXPORT_SYMBOL_GPL(sas_queuecommand);
 206
 207 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
 208 {
 209         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
 210         struct domain_device *dev = cmd_to_domain_dev(cmd);
 211         struct sas_task *task = TO_SAS_TASK(cmd);
 212
 213         /* At this point, we only get called following an actual abort
 214          * of the task, so we should be guaranteed not to be racing with
 215          * any completions from the LLD.  Task is freed after this.
 216          */
 217         sas_end_task(cmd, task);
 218
 219         if (dev_is_sata(dev)) {
 220                 /* defer commands to libata so that libata EH can
 221                  * handle ata qcs correctly
 222                  */
 223                 list_move_tail(&cmd->eh_entry, &sas_ha->eh_ata_q);
 224                 return;
 225         }
 226
 227         /* now finish the command and move it on to the error
 228          * handler done list, this also takes it off the
 229          * error handler pending list.
 230          */
 231         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
 232 }
 233
 234 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 235 {
 236         struct scsi_cmnd *cmd, *n;
 237
 238         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 239                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
 240                     cmd->device->lun == my_cmd->device->lun)
 241                         sas_eh_finish_cmd(cmd);
 242         }
 243 }
 244
 245 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 246                                      struct domain_device *dev)
 247 {
 248         struct scsi_cmnd *cmd, *n;
 249
 250         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 251                 struct domain_device *x = cmd_to_domain_dev(cmd);
 252
 253                 if (x == dev)
 254                         sas_eh_finish_cmd(cmd);
 255         }
 256 }
 257
 258 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 259                                       struct asd_sas_port *port)
 260 {
 261         struct scsi_cmnd *cmd, *n;
 262
 263         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 264                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 265                 struct asd_sas_port *x = dev->port;
 266
 267                 if (x == port)
 268                         sas_eh_finish_cmd(cmd);
 269         }
 270 }
 271
 272 enum task_disposition {
 273         TASK_IS_DONE,
 274         TASK_IS_ABORTED,
 275         TASK_IS_AT_LU,
 276         TASK_IS_NOT_AT_LU,
 277         TASK_ABORT_FAILED,
 278 };
 279
 280 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 281 {
 282         unsigned long flags;
 283         int i, res;
 284         struct sas_internal *si =
 285                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 286
 287         for (i = 0; i < 5; i++) {
 288                 pr_notice("%s: aborting task 0x%p\n", __func__, task);
 289                 res = si->dft->lldd_abort_task(task);
 290
 291                 spin_lock_irqsave(&task->task_state_lock, flags);
 292                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 293                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 294                         pr_debug("%s: task 0x%p is done\n", __func__, task);
 295                         return TASK_IS_DONE;
 296                 }
 297                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 298
 299                 if (res == TMF_RESP_FUNC_COMPLETE) {
 300                         pr_notice("%s: task 0x%p is aborted\n",
 301                                   __func__, task);
 302                         return TASK_IS_ABORTED;
 303                 } else if (si->dft->lldd_query_task) {
 304                         pr_notice("%s: querying task 0x%p\n", __func__, task);
 305                         res = si->dft->lldd_query_task(task);
 306                         switch (res) {
 307                         case TMF_RESP_FUNC_SUCC:
 308                                 pr_notice("%s: task 0x%p at LU\n", __func__,
 309                                           task);
 310                                 return TASK_IS_AT_LU;
 311                         case TMF_RESP_FUNC_COMPLETE:
 312                                 pr_notice("%s: task 0x%p not at LU\n",
 313                                           __func__, task);
 314                                 return TASK_IS_NOT_AT_LU;
 315                         case TMF_RESP_FUNC_FAILED:
 316                                 pr_notice("%s: task 0x%p failed to abort\n",
 317                                           __func__, task);
 318                                 return TASK_ABORT_FAILED;
 319                         }
 320
 321                 }
 322         }
 323         return res;
 324 }
 325
 326 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 327 {
 328         int res = TMF_RESP_FUNC_FAILED;
 329         struct scsi_lun lun;
 330         struct sas_internal *i =
 331                 to_sas_internal(dev->port->ha->core.shost->transportt);
 332
 333         int_to_scsilun(cmd->device->lun, &lun);
 334
 335         pr_notice("eh: device %016llx LUN 0x%llx has the task\n",
 336                   SAS_ADDR(dev->sas_addr),
 337                   cmd->device->lun);
 338
 339         if (i->dft->lldd_abort_task_set)
 340                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 341
 342         if (res == TMF_RESP_FUNC_FAILED) {
 343                 if (i->dft->lldd_clear_task_set)
 344                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 345         }
 346
 347         if (res == TMF_RESP_FUNC_FAILED) {
 348                 if (i->dft->lldd_lu_reset)
 349                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 350         }
 351
 352         return res;
 353 }
 354
 355 static int sas_recover_I_T(struct domain_device *dev)
 356 {
 357         int res = TMF_RESP_FUNC_FAILED;
 358         struct sas_internal *i =
 359                 to_sas_internal(dev->port->ha->core.shost->transportt);
 360
 361         pr_notice("I_T nexus reset for dev %016llx\n",
 362                   SAS_ADDR(dev->sas_addr));
 363
 364         if (i->dft->lldd_I_T_nexus_reset)
 365                 res = i->dft->lldd_I_T_nexus_reset(dev);
 366
 367         return res;
 368 }
 369
 370 /* take a reference on the last known good phy for this device */
 371 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
 372 {
 373         struct sas_ha_struct *ha = dev->port->ha;
 374         struct sas_phy *phy;
 375         unsigned long flags;
 376
 377         /* a published domain device always has a valid phy, it may be
 378          * stale, but it is never NULL
 379          */
 380         BUG_ON(!dev->phy);
 381
 382         spin_lock_irqsave(&ha->phy_port_lock, flags);
 383         phy = dev->phy;
 384         get_device(&phy->dev);
 385         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 386
 387         return phy;
 388 }
 389 EXPORT_SYMBOL_GPL(sas_get_local_phy);
 390
 391 static void sas_wait_eh(struct domain_device *dev)
 392 {
 393         struct sas_ha_struct *ha = dev->port->ha;
 394         DEFINE_WAIT(wait);
 395
 396         if (dev_is_sata(dev)) {
 397                 ata_port_wait_eh(dev->sata_dev.ap);
 398                 return;
 399         }
 400  retry:
 401         spin_lock_irq(&ha->lock);
 402
 403         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
 404                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 405                 spin_unlock_irq(&ha->lock);
 406                 schedule();
 407                 spin_lock_irq(&ha->lock);
 408         }
 409         finish_wait(&ha->eh_wait_q, &wait);
 410
 411         spin_unlock_irq(&ha->lock);
 412
 413         /* make sure SCSI EH is complete */
 414         if (scsi_host_in_recovery(ha->core.shost)) {
 415                 msleep(10);
 416                 goto retry;
 417         }
 418 }
 419
 420 static int sas_queue_reset(struct domain_device *dev, int reset_type,
 421                            u64 lun, int wait)
 422 {
 423         struct sas_ha_struct *ha = dev->port->ha;
 424         int scheduled = 0, tries = 100;
 425
 426         /* ata: promote lun reset to bus reset */
 427         if (dev_is_sata(dev)) {
 428                 sas_ata_schedule_reset(dev);
 429                 if (wait)
 430                         sas_ata_wait_eh(dev);
 431                 return SUCCESS;
 432         }
 433
 434         while (!scheduled && tries--) {
 435                 spin_lock_irq(&ha->lock);
 436                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
 437                     !test_bit(reset_type, &dev->state)) {
 438                         scheduled = 1;
 439                         ha->eh_active++;
 440                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
 441                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
 442                         set_bit(reset_type, &dev->state);
 443                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
 444                         scsi_schedule_eh(ha->core.shost);
 445                 }
 446                 spin_unlock_irq(&ha->lock);
 447
 448                 if (wait)
 449                         sas_wait_eh(dev);
 450
 451                 if (scheduled)
 452                         return SUCCESS;
 453         }
 454
 455         pr_warn("%s reset of %s failed\n",
 456                 reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
 457                 dev_name(&dev->rphy->dev));
 458
 459         return FAILED;
 460 }
 461
 462 int sas_eh_abort_handler(struct scsi_cmnd *cmd)
 463 {
 464         int res = TMF_RESP_FUNC_FAILED;
 465         struct sas_task *task = TO_SAS_TASK(cmd);
 466         struct Scsi_Host *host = cmd->device->host;
 467         struct domain_device *dev = cmd_to_domain_dev(cmd);
 468         struct sas_internal *i = to_sas_internal(host->transportt);
 469         unsigned long flags;
 470
 471         if (!i->dft->lldd_abort_task)
 472                 return FAILED;
 473
 474         spin_lock_irqsave(host->host_lock, flags);
 475         /* We cannot do async aborts for SATA devices */
 476         if (dev_is_sata(dev) && !host->host_eh_scheduled) {
 477                 spin_unlock_irqrestore(host->host_lock, flags);
 478                 return FAILED;
 479         }
 480         spin_unlock_irqrestore(host->host_lock, flags);
 481
 482         if (task)
 483                 res = i->dft->lldd_abort_task(task);
 484         else
 485                 pr_notice("no task to abort\n");
 486         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 487                 return SUCCESS;
 488
 489         return FAILED;
 490 }
 491 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
 492
 493 /* Attempt to send a LUN reset message to a device */
 494 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 495 {
 496         int res;
 497         struct scsi_lun lun;
 498         struct Scsi_Host *host = cmd->device->host;
 499         struct domain_device *dev = cmd_to_domain_dev(cmd);
 500         struct sas_internal *i = to_sas_internal(host->transportt);
 501
 502         if (current != host->ehandler)
 503                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
 504
 505         int_to_scsilun(cmd->device->lun, &lun);
 506
 507         if (!i->dft->lldd_lu_reset)
 508                 return FAILED;
 509
 510         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 511         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 512                 return SUCCESS;
 513
 514         return FAILED;
 515 }
 516 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
 517
 518 int sas_eh_target_reset_handler(struct scsi_cmnd *cmd)
 519 {
 520         int res;
 521         struct Scsi_Host *host = cmd->device->host;
 522         struct domain_device *dev = cmd_to_domain_dev(cmd);
 523         struct sas_internal *i = to_sas_internal(host->transportt);
 524
 525         if (current != host->ehandler)
 526                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
 527
 528         if (!i->dft->lldd_I_T_nexus_reset)
 529                 return FAILED;
 530
 531         res = i->dft->lldd_I_T_nexus_reset(dev);
 532         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
 533             res == -ENODEV)
 534                 return SUCCESS;
 535
 536         return FAILED;
 537 }
 538 EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
 539
 540 /* Try to reset a device */
 541 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
 542 {
 543         int res;
 544         struct Scsi_Host *shost = cmd->device->host;
 545
 546         if (!shost->hostt->eh_device_reset_handler)
 547                 goto try_target_reset;
 548
 549         res = shost->hostt->eh_device_reset_handler(cmd);
 550         if (res == SUCCESS)
 551                 return res;
 552
 553 try_target_reset:
 554         if (shost->hostt->eh_target_reset_handler)
 555                 return shost->hostt->eh_target_reset_handler(cmd);
 556
 557         return FAILED;
 558 }
 559
 560 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
 561 {
 562         struct scsi_cmnd *cmd, *n;
 563         enum task_disposition res = TASK_IS_DONE;
 564         int tmf_resp, need_reset;
 565         struct sas_internal *i = to_sas_internal(shost->transportt);
 566         unsigned long flags;
 567         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 568         LIST_HEAD(done);
 569
 570         /* clean out any commands that won the completion vs eh race */
 571         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 572                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 573                 struct sas_task *task;
 574
 575                 spin_lock_irqsave(&dev->done_lock, flags);
 576                 /* by this point the lldd has either observed
 577                  * SAS_HA_FROZEN and is leaving the task alone, or has
 578                  * won the race with eh and decided to complete it
 579                  */
 580                 task = TO_SAS_TASK(cmd);
 581                 spin_unlock_irqrestore(&dev->done_lock, flags);
 582
 583                 if (!task)
 584                         list_move_tail(&cmd->eh_entry, &done);
 585         }
 586
 587  Again:
 588         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 589                 struct sas_task *task = TO_SAS_TASK(cmd);
 590
 591                 list_del_init(&cmd->eh_entry);
 592
 593                 spin_lock_irqsave(&task->task_state_lock, flags);
 594                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 595                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 596
 597                 if (need_reset) {
 598                         pr_notice("%s: task 0x%p requests reset\n",
 599                                   __func__, task);
 600                         goto reset;
 601                 }
 602
 603                 pr_debug("trying to find task 0x%p\n", task);
 604                 res = sas_scsi_find_task(task);
 605
 606                 switch (res) {
 607                 case TASK_IS_DONE:
 608                         pr_notice("%s: task 0x%p is done\n", __func__,
 609                                     task);
 610                         sas_eh_finish_cmd(cmd);
 611                         continue;
 612                 case TASK_IS_ABORTED:
 613                         pr_notice("%s: task 0x%p is aborted\n",
 614                                   __func__, task);
 615                         sas_eh_finish_cmd(cmd);
 616                         continue;
 617                 case TASK_IS_AT_LU:
 618                         pr_info("task 0x%p is at LU: lu recover\n", task);
 619  reset:
 620                         tmf_resp = sas_recover_lu(task->dev, cmd);
 621                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 622                                 pr_notice("dev %016llx LU 0x%llx is recovered\n",
 623                                           SAS_ADDR(task->dev),
 624                                           cmd->device->lun);
 625                                 sas_eh_finish_cmd(cmd);
 626                                 sas_scsi_clear_queue_lu(work_q, cmd);
 627                                 goto Again;
 628                         }
 629                         fallthrough;
 630                 case TASK_IS_NOT_AT_LU:
 631                 case TASK_ABORT_FAILED:
 632                         pr_notice("task 0x%p is not at LU: I_T recover\n",
 633                                   task);
 634                         tmf_resp = sas_recover_I_T(task->dev);
 635                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
 636                             tmf_resp == -ENODEV) {
 637                                 struct domain_device *dev = task->dev;
 638                                 pr_notice("I_T %016llx recovered\n",
 639                                           SAS_ADDR(task->dev->sas_addr));
 640                                 sas_eh_finish_cmd(cmd);
 641                                 sas_scsi_clear_queue_I_T(work_q, dev);
 642                                 goto Again;
 643                         }
 644                         /* Hammer time :-) */
 645                         try_to_reset_cmd_device(cmd);
 646                         if (i->dft->lldd_clear_nexus_port) {
 647                                 struct asd_sas_port *port = task->dev->port;
 648                                 pr_debug("clearing nexus for port:%d\n",
 649                                           port->id);
 650                                 res = i->dft->lldd_clear_nexus_port(port);
 651                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 652                                         pr_notice("clear nexus port:%d succeeded\n",
 653                                                   port->id);
 654                                         sas_eh_finish_cmd(cmd);
 655                                         sas_scsi_clear_queue_port(work_q,
 656                                                                   port);
 657                                         goto Again;
 658                                 }
 659                         }
 660                         if (i->dft->lldd_clear_nexus_ha) {
 661                                 pr_debug("clear nexus ha\n");
 662                                 res = i->dft->lldd_clear_nexus_ha(ha);
 663                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 664                                         pr_notice("clear nexus ha succeeded\n");
 665                                         sas_eh_finish_cmd(cmd);
 666                                         goto clear_q;
 667                                 }
 668                         }
 669                         /* If we are here -- this means that no amount
 670                          * of effort could recover from errors.  Quite
 671                          * possibly the HA just disappeared.
 672                          */
 673                         pr_err("error from device %016llx, LUN 0x%llx couldn't be recovered in any way\n",
 674                                SAS_ADDR(task->dev->sas_addr),
 675                                cmd->device->lun);
 676
 677                         sas_eh_finish_cmd(cmd);
 678                         goto clear_q;
 679                 }
 680         }
 681  out:
 682         list_splice_tail(&done, work_q);
 683         list_splice_tail_init(&ha->eh_ata_q, work_q);
 684         return;
 685
 686  clear_q:
 687         pr_debug("--- Exit %s -- clear_q\n", __func__);
 688         list_for_each_entry_safe(cmd, n, work_q, eh_entry)
 689                 sas_eh_finish_cmd(cmd);
 690         goto out;
 691 }
 692
 693 static void sas_eh_handle_resets(struct Scsi_Host *shost)
 694 {
 695         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 696         struct sas_internal *i = to_sas_internal(shost->transportt);
 697
 698         /* handle directed resets to sas devices */
 699         spin_lock_irq(&ha->lock);
 700         while (!list_empty(&ha->eh_dev_q)) {
 701                 struct domain_device *dev;
 702                 struct ssp_device *ssp;
 703
 704                 ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
 705                 list_del_init(&ssp->eh_list_node);
 706                 dev = container_of(ssp, typeof(*dev), ssp_dev);
 707                 kref_get(&dev->kref);
 708                 WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
 709
 710                 spin_unlock_irq(&ha->lock);
 711
 712                 if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
 713                         i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
 714
 715                 if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
 716                         i->dft->lldd_I_T_nexus_reset(dev);
 717
 718                 sas_put_device(dev);
 719                 spin_lock_irq(&ha->lock);
 720                 clear_bit(SAS_DEV_EH_PENDING, &dev->state);
 721                 ha->eh_active--;
 722         }
 723         spin_unlock_irq(&ha->lock);
 724 }
 725
 726
 727 void sas_scsi_recover_host(struct Scsi_Host *shost)
 728 {
 729         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 730         LIST_HEAD(eh_work_q);
 731         int tries = 0;
 732         bool retry;
 733
 734 retry:
 735         tries++;
 736         retry = true;
 737         spin_lock_irq(shost->host_lock);
 738         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
 739         spin_unlock_irq(shost->host_lock);
 740
 741         pr_notice("Enter %s busy: %d failed: %d\n",
 742                   __func__, scsi_host_busy(shost), shost->host_failed);
 743         /*
 744          * Deal with commands that still have SAS tasks (i.e. they didn't
 745          * complete via the normal sas_task completion mechanism),
 746          * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
 747          */
 748         set_bit(SAS_HA_FROZEN, &ha->state);
 749         sas_eh_handle_sas_errors(shost, &eh_work_q);
 750         clear_bit(SAS_HA_FROZEN, &ha->state);
 751         if (list_empty(&eh_work_q))
 752                 goto out;
 753
 754         /*
 755          * Now deal with SCSI commands that completed ok but have a an error
 756          * code (and hopefully sense data) attached.  This is roughly what
 757          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
 758          * command we see here has no sas_task and is thus unknown to the HA.
 759          */
 760         sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
 761         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
 762                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
 763
 764 out:
 765         sas_eh_handle_resets(shost);
 766
 767         /* now link into libata eh --- if we have any ata devices */
 768         sas_ata_strategy_handler(shost);
 769
 770         scsi_eh_flush_done_q(&ha->eh_done_q);
 771
 772         /* check if any new eh work was scheduled during the last run */
 773         spin_lock_irq(&ha->lock);
 774         if (ha->eh_active == 0) {
 775                 shost->host_eh_scheduled = 0;
 776                 retry = false;
 777         }
 778         spin_unlock_irq(&ha->lock);
 779
 780         if (retry)
 781                 goto retry;
 782
 783         pr_notice("--- Exit %s: busy: %d failed: %d tries: %d\n",
 784                   __func__, scsi_host_busy(shost),
 785                   shost->host_failed, tries);
 786 }
 787
 788 int sas_ioctl(struct scsi_device *sdev, unsigned int cmd, void __user *arg)
 789 {
 790         struct domain_device *dev = sdev_to_domain_dev(sdev);
 791
 792         if (dev_is_sata(dev))
 793                 return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
 794
 795         return -EINVAL;
 796 }
 797 EXPORT_SYMBOL_GPL(sas_ioctl);
 798
 799 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
 800 {
 801         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
 802         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 803         struct domain_device *found_dev = NULL;
 804         int i;
 805         unsigned long flags;
 806
 807         spin_lock_irqsave(&ha->phy_port_lock, flags);
 808         for (i = 0; i < ha->num_phys; i++) {
 809                 struct asd_sas_port *port = ha->sas_port[i];
 810                 struct domain_device *dev;
 811
 812                 spin_lock(&port->dev_list_lock);
 813                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
 814                         if (rphy == dev->rphy) {
 815                                 found_dev = dev;
 816                                 spin_unlock(&port->dev_list_lock);
 817                                 goto found;
 818                         }
 819                 }
 820                 spin_unlock(&port->dev_list_lock);
 821         }
 822  found:
 823         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 824
 825         return found_dev;
 826 }
 827
 828 int sas_target_alloc(struct scsi_target *starget)
 829 {
 830         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
 831         struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
 832
 833         if (!found_dev)
 834                 return -ENODEV;
 835
 836         kref_get(&found_dev->kref);
 837         starget->hostdata = found_dev;
 838         return 0;
 839 }
 840 EXPORT_SYMBOL_GPL(sas_target_alloc);
 841
 842 #define SAS_DEF_QD 256
 843
 844 int sas_slave_configure(struct scsi_device *scsi_dev)
 845 {
 846         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 847
 848         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
 849
 850         if (dev_is_sata(dev)) {
 851                 ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
 852                 return 0;
 853         }
 854
 855         sas_read_port_mode_page(scsi_dev);
 856
 857         if (scsi_dev->tagged_supported) {
 858                 scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
 859         } else {
 860                 pr_notice("device %016llx, LUN 0x%llx doesn't support TCQ\n",
 861                           SAS_ADDR(dev->sas_addr), scsi_dev->lun);
 862                 scsi_change_queue_depth(scsi_dev, 1);
 863         }
 864
 865         scsi_dev->allow_restart = 1;
 866
 867         return 0;
 868 }
 869 EXPORT_SYMBOL_GPL(sas_slave_configure);
 870
 871 int sas_change_queue_depth(struct scsi_device *sdev, int depth)
 872 {
 873         struct domain_device *dev = sdev_to_domain_dev(sdev);
 874
 875         if (dev_is_sata(dev))
 876                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
 877
 878         if (!sdev->tagged_supported)
 879                 depth = 1;
 880         return scsi_change_queue_depth(sdev, depth);
 881 }
 882 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
 883
 884 int sas_bios_param(struct scsi_device *scsi_dev,
 885                           struct block_device *bdev,
 886                           sector_t capacity, int *hsc)
 887 {
 888         hsc[0] = 255;
 889         hsc[1] = 63;
 890         sector_div(capacity, 255*63);
 891         hsc[2] = capacity;
 892
 893         return 0;
 894 }
 895 EXPORT_SYMBOL_GPL(sas_bios_param);
 896
 897 /*
 898  * Tell an upper layer that it needs to initiate an abort for a given task.
 899  * This should only ever be called by an LLDD.
 900  */
 901 void sas_task_abort(struct sas_task *task)
 902 {
 903         struct scsi_cmnd *sc = task->uldd_task;
 904
 905         /* Escape for libsas internal commands */
 906         if (!sc) {
 907                 struct sas_task_slow *slow = task->slow_task;
 908
 909                 if (!slow)
 910                         return;
 911                 if (!del_timer(&slow->timer))
 912                         return;
 913                 slow->timer.function(&slow->timer);
 914                 return;
 915         }
 916
 917         if (dev_is_sata(task->dev))
 918                 sas_ata_task_abort(task);
 919         else
 920                 blk_abort_request(scsi_cmd_to_rq(sc));
 921 }
 922 EXPORT_SYMBOL_GPL(sas_task_abort);
 923
 924 int sas_slave_alloc(struct scsi_device *sdev)
 925 {
 926         if (dev_is_sata(sdev_to_domain_dev(sdev)) && sdev->lun)
 927                 return -ENXIO;
 928
 929         return 0;
 930 }
 931 EXPORT_SYMBOL_GPL(sas_slave_alloc);
 932
 933 void sas_target_destroy(struct scsi_target *starget)
 934 {
 935         struct domain_device *found_dev = starget->hostdata;
 936
 937         if (!found_dev)
 938                 return;
 939
 940         starget->hostdata = NULL;
 941         sas_put_device(found_dev);
 942 }
 943 EXPORT_SYMBOL_GPL(sas_target_destroy);
 944
 945 #define SAS_STRING_ADDR_SIZE    16
 946
 947 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
 948 {
 949         int res;
 950         const struct firmware *fw;
 951
 952         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
 953         if (res)
 954                 return res;
 955
 956         if (fw->size < SAS_STRING_ADDR_SIZE) {
 957                 res = -ENODEV;
 958                 goto out;
 959         }
 960
 961         res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
 962         if (res)
 963                 goto out;
 964
 965 out:
 966         release_firmware(fw);
 967         return res;
 968 }
 969 EXPORT_SYMBOL_GPL(sas_request_addr);
 970