drivers/scsi/libsas/sas_scsi_host.c

   1 /*
   2  * Serial Attached SCSI (SAS) class SCSI Host glue.
   3  *
   4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
   5  * Copyright (C) 2005 Luben Tuikov <[email protected]>
   6  *
   7  * This file is licensed under GPLv2.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of the
  12  * License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  22  * USA
  23  *
  24  */
  25
  26 #include <linux/kthread.h>
  27 #include <linux/firmware.h>
  28 #include <linux/export.h>
  29 #include <linux/ctype.h>
  30 #include <linux/kernel.h>
  31
  32 #include "sas_internal.h"
  33
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi_device.h>
  36 #include <scsi/scsi_tcq.h>
  37 #include <scsi/scsi.h>
  38 #include <scsi/scsi_eh.h>
  39 #include <scsi/scsi_transport.h>
  40 #include <scsi/scsi_transport_sas.h>
  41 #include <scsi/sas_ata.h>
  42 #include "../scsi_sas_internal.h"
  43 #include "../scsi_transport_api.h"
  44 #include "../scsi_priv.h"
  45
  46 #include <linux/err.h>
  47 #include <linux/blkdev.h>
  48 #include <linux/freezer.h>
  49 #include <linux/gfp.h>
  50 #include <linux/scatterlist.h>
  51 #include <linux/libata.h>
  52
  53 /* record final status and free the task */
  54 static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
  55 {
  56         struct task_status_struct *ts = &task->task_status;
  57         int hs = 0, stat = 0;
  58
  59         if (ts->resp == SAS_TASK_UNDELIVERED) {
  60                 /* transport error */
  61                 hs = DID_NO_CONNECT;
  62         } else { /* ts->resp == SAS_TASK_COMPLETE */
  63                 /* task delivered, what happened afterwards? */
  64                 switch (ts->stat) {
  65                 case SAS_DEV_NO_RESPONSE:
  66                 case SAS_INTERRUPTED:
  67                 case SAS_PHY_DOWN:
  68                 case SAS_NAK_R_ERR:
  69                 case SAS_OPEN_TO:
  70                         hs = DID_NO_CONNECT;
  71                         break;
  72                 case SAS_DATA_UNDERRUN:
  73                         scsi_set_resid(sc, ts->residual);
  74                         if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
  75                                 hs = DID_ERROR;
  76                         break;
  77                 case SAS_DATA_OVERRUN:
  78                         hs = DID_ERROR;
  79                         break;
  80                 case SAS_QUEUE_FULL:
  81                         hs = DID_SOFT_ERROR; /* retry */
  82                         break;
  83                 case SAS_DEVICE_UNKNOWN:
  84                         hs = DID_BAD_TARGET;
  85                         break;
  86                 case SAS_SG_ERR:
  87                         hs = DID_PARITY;
  88                         break;
  89                 case SAS_OPEN_REJECT:
  90                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
  91                                 hs = DID_SOFT_ERROR; /* retry */
  92                         else
  93                                 hs = DID_ERROR;
  94                         break;
  95                 case SAS_PROTO_RESPONSE:
  96                         pr_notice("LLDD:%s sent SAS_PROTO_RESP for an SSP task; please report this\n",
  97                                   task->dev->port->ha->sas_ha_name);
  98                         break;
  99                 case SAS_ABORTED_TASK:
 100                         hs = DID_ABORT;
 101                         break;
 102                 case SAM_STAT_CHECK_CONDITION:
 103                         memcpy(sc->sense_buffer, ts->buf,
 104                                min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
 105                         stat = SAM_STAT_CHECK_CONDITION;
 106                         break;
 107                 default:
 108                         stat = ts->stat;
 109                         break;
 110                 }
 111         }
 112
 113         sc->result = (hs << 16) | stat;
 114         ASSIGN_SAS_TASK(sc, NULL);
 115         sas_free_task(task);
 116 }
 117
 118 static void sas_scsi_task_done(struct sas_task *task)
 119 {
 120         struct scsi_cmnd *sc = task->uldd_task;
 121         struct domain_device *dev = task->dev;
 122         struct sas_ha_struct *ha = dev->port->ha;
 123         unsigned long flags;
 124
 125         spin_lock_irqsave(&dev->done_lock, flags);
 126         if (test_bit(SAS_HA_FROZEN, &ha->state))
 127                 task = NULL;
 128         else
 129                 ASSIGN_SAS_TASK(sc, NULL);
 130         spin_unlock_irqrestore(&dev->done_lock, flags);
 131
 132         if (unlikely(!task)) {
 133                 /* task will be completed by the error handler */
 134                 pr_debug("task done but aborted\n");
 135                 return;
 136         }
 137
 138         if (unlikely(!sc)) {
 139                 pr_debug("task_done called with non existing SCSI cmnd!\n");
 140                 sas_free_task(task);
 141                 return;
 142         }
 143
 144         sas_end_task(sc, task);
 145         sc->scsi_done(sc);
 146 }
 147
 148 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 149                                                struct domain_device *dev,
 150                                                gfp_t gfp_flags)
 151 {
 152         struct sas_task *task = sas_alloc_task(gfp_flags);
 153         struct scsi_lun lun;
 154
 155         if (!task)
 156                 return NULL;
 157
 158         task->uldd_task = cmd;
 159         ASSIGN_SAS_TASK(cmd, task);
 160
 161         task->dev = dev;
 162         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
 163
 164         task->ssp_task.retry_count = 1;
 165         int_to_scsilun(cmd->device->lun, &lun);
 166         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
 167         task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
 168         task->ssp_task.cmd = cmd;
 169
 170         task->scatter = scsi_sglist(cmd);
 171         task->num_scatter = scsi_sg_count(cmd);
 172         task->total_xfer_len = scsi_bufflen(cmd);
 173         task->data_dir = cmd->sc_data_direction;
 174
 175         task->task_done = sas_scsi_task_done;
 176
 177         return task;
 178 }
 179
 180 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 181 {
 182         struct sas_internal *i = to_sas_internal(host->transportt);
 183         struct domain_device *dev = cmd_to_domain_dev(cmd);
 184         struct sas_task *task;
 185         int res = 0;
 186
 187         /* If the device fell off, no sense in issuing commands */
 188         if (test_bit(SAS_DEV_GONE, &dev->state)) {
 189                 cmd->result = DID_BAD_TARGET << 16;
 190                 goto out_done;
 191         }
 192
 193         if (dev_is_sata(dev)) {
 194                 spin_lock_irq(dev->sata_dev.ap->lock);
 195                 res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
 196                 spin_unlock_irq(dev->sata_dev.ap->lock);
 197                 return res;
 198         }
 199
 200         task = sas_create_task(cmd, dev, GFP_ATOMIC);
 201         if (!task)
 202                 return SCSI_MLQUEUE_HOST_BUSY;
 203
 204         res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
 205         if (res)
 206                 goto out_free_task;
 207         return 0;
 208
 209 out_free_task:
 210         pr_debug("lldd_execute_task returned: %d\n", res);
 211         ASSIGN_SAS_TASK(cmd, NULL);
 212         sas_free_task(task);
 213         if (res == -SAS_QUEUE_FULL)
 214                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
 215         else
 216                 cmd->result = DID_ERROR << 16;
 217 out_done:
 218         cmd->scsi_done(cmd);
 219         return 0;
 220 }
 221
 222 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
 223 {
 224         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
 225         struct domain_device *dev = cmd_to_domain_dev(cmd);
 226         struct sas_task *task = TO_SAS_TASK(cmd);
 227
 228         /* At this point, we only get called following an actual abort
 229          * of the task, so we should be guaranteed not to be racing with
 230          * any completions from the LLD.  Task is freed after this.
 231          */
 232         sas_end_task(cmd, task);
 233
 234         if (dev_is_sata(dev)) {
 235                 /* defer commands to libata so that libata EH can
 236                  * handle ata qcs correctly
 237                  */
 238                 list_move_tail(&cmd->eh_entry, &sas_ha->eh_ata_q);
 239                 return;
 240         }
 241
 242         /* now finish the command and move it on to the error
 243          * handler done list, this also takes it off the
 244          * error handler pending list.
 245          */
 246         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
 247 }
 248
 249 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 250 {
 251         struct scsi_cmnd *cmd, *n;
 252
 253         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 254                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
 255                     cmd->device->lun == my_cmd->device->lun)
 256                         sas_eh_finish_cmd(cmd);
 257         }
 258 }
 259
 260 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 261                                      struct domain_device *dev)
 262 {
 263         struct scsi_cmnd *cmd, *n;
 264
 265         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 266                 struct domain_device *x = cmd_to_domain_dev(cmd);
 267
 268                 if (x == dev)
 269                         sas_eh_finish_cmd(cmd);
 270         }
 271 }
 272
 273 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 274                                       struct asd_sas_port *port)
 275 {
 276         struct scsi_cmnd *cmd, *n;
 277
 278         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 279                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 280                 struct asd_sas_port *x = dev->port;
 281
 282                 if (x == port)
 283                         sas_eh_finish_cmd(cmd);
 284         }
 285 }
 286
 287 enum task_disposition {
 288         TASK_IS_DONE,
 289         TASK_IS_ABORTED,
 290         TASK_IS_AT_LU,
 291         TASK_IS_NOT_AT_LU,
 292         TASK_ABORT_FAILED,
 293 };
 294
 295 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 296 {
 297         unsigned long flags;
 298         int i, res;
 299         struct sas_internal *si =
 300                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 301
 302         for (i = 0; i < 5; i++) {
 303                 pr_notice("%s: aborting task 0x%p\n", __func__, task);
 304                 res = si->dft->lldd_abort_task(task);
 305
 306                 spin_lock_irqsave(&task->task_state_lock, flags);
 307                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 308                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 309                         pr_debug("%s: task 0x%p is done\n", __func__, task);
 310                         return TASK_IS_DONE;
 311                 }
 312                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 313
 314                 if (res == TMF_RESP_FUNC_COMPLETE) {
 315                         pr_notice("%s: task 0x%p is aborted\n",
 316                                   __func__, task);
 317                         return TASK_IS_ABORTED;
 318                 } else if (si->dft->lldd_query_task) {
 319                         pr_notice("%s: querying task 0x%p\n", __func__, task);
 320                         res = si->dft->lldd_query_task(task);
 321                         switch (res) {
 322                         case TMF_RESP_FUNC_SUCC:
 323                                 pr_notice("%s: task 0x%p at LU\n", __func__,
 324                                           task);
 325                                 return TASK_IS_AT_LU;
 326                         case TMF_RESP_FUNC_COMPLETE:
 327                                 pr_notice("%s: task 0x%p not at LU\n",
 328                                           __func__, task);
 329                                 return TASK_IS_NOT_AT_LU;
 330                         case TMF_RESP_FUNC_FAILED:
 331                                 pr_notice("%s: task 0x%p failed to abort\n",
 332                                           __func__, task);
 333                                 return TASK_ABORT_FAILED;
 334                         }
 335
 336                 }
 337         }
 338         return res;
 339 }
 340
 341 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 342 {
 343         int res = TMF_RESP_FUNC_FAILED;
 344         struct scsi_lun lun;
 345         struct sas_internal *i =
 346                 to_sas_internal(dev->port->ha->core.shost->transportt);
 347
 348         int_to_scsilun(cmd->device->lun, &lun);
 349
 350         pr_notice("eh: device %llx LUN %llx has the task\n",
 351                   SAS_ADDR(dev->sas_addr),
 352                   cmd->device->lun);
 353
 354         if (i->dft->lldd_abort_task_set)
 355                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 356
 357         if (res == TMF_RESP_FUNC_FAILED) {
 358                 if (i->dft->lldd_clear_task_set)
 359                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 360         }
 361
 362         if (res == TMF_RESP_FUNC_FAILED) {
 363                 if (i->dft->lldd_lu_reset)
 364                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 365         }
 366
 367         return res;
 368 }
 369
 370 static int sas_recover_I_T(struct domain_device *dev)
 371 {
 372         int res = TMF_RESP_FUNC_FAILED;
 373         struct sas_internal *i =
 374                 to_sas_internal(dev->port->ha->core.shost->transportt);
 375
 376         pr_notice("I_T nexus reset for dev %016llx\n",
 377                   SAS_ADDR(dev->sas_addr));
 378
 379         if (i->dft->lldd_I_T_nexus_reset)
 380                 res = i->dft->lldd_I_T_nexus_reset(dev);
 381
 382         return res;
 383 }
 384
 385 /* take a reference on the last known good phy for this device */
 386 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
 387 {
 388         struct sas_ha_struct *ha = dev->port->ha;
 389         struct sas_phy *phy;
 390         unsigned long flags;
 391
 392         /* a published domain device always has a valid phy, it may be
 393          * stale, but it is never NULL
 394          */
 395         BUG_ON(!dev->phy);
 396
 397         spin_lock_irqsave(&ha->phy_port_lock, flags);
 398         phy = dev->phy;
 399         get_device(&phy->dev);
 400         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 401
 402         return phy;
 403 }
 404 EXPORT_SYMBOL_GPL(sas_get_local_phy);
 405
 406 static void sas_wait_eh(struct domain_device *dev)
 407 {
 408         struct sas_ha_struct *ha = dev->port->ha;
 409         DEFINE_WAIT(wait);
 410
 411         if (dev_is_sata(dev)) {
 412                 ata_port_wait_eh(dev->sata_dev.ap);
 413                 return;
 414         }
 415  retry:
 416         spin_lock_irq(&ha->lock);
 417
 418         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
 419                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 420                 spin_unlock_irq(&ha->lock);
 421                 schedule();
 422                 spin_lock_irq(&ha->lock);
 423         }
 424         finish_wait(&ha->eh_wait_q, &wait);
 425
 426         spin_unlock_irq(&ha->lock);
 427
 428         /* make sure SCSI EH is complete */
 429         if (scsi_host_in_recovery(ha->core.shost)) {
 430                 msleep(10);
 431                 goto retry;
 432         }
 433 }
 434 EXPORT_SYMBOL(sas_wait_eh);
 435
 436 static int sas_queue_reset(struct domain_device *dev, int reset_type,
 437                            u64 lun, int wait)
 438 {
 439         struct sas_ha_struct *ha = dev->port->ha;
 440         int scheduled = 0, tries = 100;
 441
 442         /* ata: promote lun reset to bus reset */
 443         if (dev_is_sata(dev)) {
 444                 sas_ata_schedule_reset(dev);
 445                 if (wait)
 446                         sas_ata_wait_eh(dev);
 447                 return SUCCESS;
 448         }
 449
 450         while (!scheduled && tries--) {
 451                 spin_lock_irq(&ha->lock);
 452                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
 453                     !test_bit(reset_type, &dev->state)) {
 454                         scheduled = 1;
 455                         ha->eh_active++;
 456                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
 457                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
 458                         set_bit(reset_type, &dev->state);
 459                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
 460                         scsi_schedule_eh(ha->core.shost);
 461                 }
 462                 spin_unlock_irq(&ha->lock);
 463
 464                 if (wait)
 465                         sas_wait_eh(dev);
 466
 467                 if (scheduled)
 468                         return SUCCESS;
 469         }
 470
 471         pr_warn("%s reset of %s failed\n",
 472                 reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
 473                 dev_name(&dev->rphy->dev));
 474
 475         return FAILED;
 476 }
 477
 478 int sas_eh_abort_handler(struct scsi_cmnd *cmd)
 479 {
 480         int res = TMF_RESP_FUNC_FAILED;
 481         struct sas_task *task = TO_SAS_TASK(cmd);
 482         struct Scsi_Host *host = cmd->device->host;
 483         struct domain_device *dev = cmd_to_domain_dev(cmd);
 484         struct sas_internal *i = to_sas_internal(host->transportt);
 485         unsigned long flags;
 486
 487         if (!i->dft->lldd_abort_task)
 488                 return FAILED;
 489
 490         spin_lock_irqsave(host->host_lock, flags);
 491         /* We cannot do async aborts for SATA devices */
 492         if (dev_is_sata(dev) && !host->host_eh_scheduled) {
 493                 spin_unlock_irqrestore(host->host_lock, flags);
 494                 return FAILED;
 495         }
 496         spin_unlock_irqrestore(host->host_lock, flags);
 497
 498         if (task)
 499                 res = i->dft->lldd_abort_task(task);
 500         else
 501                 pr_notice("no task to abort\n");
 502         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 503                 return SUCCESS;
 504
 505         return FAILED;
 506 }
 507 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
 508
 509 /* Attempt to send a LUN reset message to a device */
 510 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 511 {
 512         int res;
 513         struct scsi_lun lun;
 514         struct Scsi_Host *host = cmd->device->host;
 515         struct domain_device *dev = cmd_to_domain_dev(cmd);
 516         struct sas_internal *i = to_sas_internal(host->transportt);
 517
 518         if (current != host->ehandler)
 519                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
 520
 521         int_to_scsilun(cmd->device->lun, &lun);
 522
 523         if (!i->dft->lldd_lu_reset)
 524                 return FAILED;
 525
 526         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 527         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 528                 return SUCCESS;
 529
 530         return FAILED;
 531 }
 532
 533 int sas_eh_target_reset_handler(struct scsi_cmnd *cmd)
 534 {
 535         int res;
 536         struct Scsi_Host *host = cmd->device->host;
 537         struct domain_device *dev = cmd_to_domain_dev(cmd);
 538         struct sas_internal *i = to_sas_internal(host->transportt);
 539
 540         if (current != host->ehandler)
 541                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
 542
 543         if (!i->dft->lldd_I_T_nexus_reset)
 544                 return FAILED;
 545
 546         res = i->dft->lldd_I_T_nexus_reset(dev);
 547         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
 548             res == -ENODEV)
 549                 return SUCCESS;
 550
 551         return FAILED;
 552 }
 553
 554 /* Try to reset a device */
 555 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
 556 {
 557         int res;
 558         struct Scsi_Host *shost = cmd->device->host;
 559
 560         if (!shost->hostt->eh_device_reset_handler)
 561                 goto try_target_reset;
 562
 563         res = shost->hostt->eh_device_reset_handler(cmd);
 564         if (res == SUCCESS)
 565                 return res;
 566
 567 try_target_reset:
 568         if (shost->hostt->eh_target_reset_handler)
 569                 return shost->hostt->eh_target_reset_handler(cmd);
 570
 571         return FAILED;
 572 }
 573
 574 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
 575 {
 576         struct scsi_cmnd *cmd, *n;
 577         enum task_disposition res = TASK_IS_DONE;
 578         int tmf_resp, need_reset;
 579         struct sas_internal *i = to_sas_internal(shost->transportt);
 580         unsigned long flags;
 581         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 582         LIST_HEAD(done);
 583
 584         /* clean out any commands that won the completion vs eh race */
 585         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 586                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 587                 struct sas_task *task;
 588
 589                 spin_lock_irqsave(&dev->done_lock, flags);
 590                 /* by this point the lldd has either observed
 591                  * SAS_HA_FROZEN and is leaving the task alone, or has
 592                  * won the race with eh and decided to complete it
 593                  */
 594                 task = TO_SAS_TASK(cmd);
 595                 spin_unlock_irqrestore(&dev->done_lock, flags);
 596
 597                 if (!task)
 598                         list_move_tail(&cmd->eh_entry, &done);
 599         }
 600
 601  Again:
 602         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 603                 struct sas_task *task = TO_SAS_TASK(cmd);
 604
 605                 list_del_init(&cmd->eh_entry);
 606
 607                 spin_lock_irqsave(&task->task_state_lock, flags);
 608                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 609                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 610
 611                 if (need_reset) {
 612                         pr_notice("%s: task 0x%p requests reset\n",
 613                                   __func__, task);
 614                         goto reset;
 615                 }
 616
 617                 pr_debug("trying to find task 0x%p\n", task);
 618                 res = sas_scsi_find_task(task);
 619
 620                 switch (res) {
 621                 case TASK_IS_DONE:
 622                         pr_notice("%s: task 0x%p is done\n", __func__,
 623                                     task);
 624                         sas_eh_finish_cmd(cmd);
 625                         continue;
 626                 case TASK_IS_ABORTED:
 627                         pr_notice("%s: task 0x%p is aborted\n",
 628                                   __func__, task);
 629                         sas_eh_finish_cmd(cmd);
 630                         continue;
 631                 case TASK_IS_AT_LU:
 632                         pr_info("task 0x%p is at LU: lu recover\n", task);
 633  reset:
 634                         tmf_resp = sas_recover_lu(task->dev, cmd);
 635                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 636                                 pr_notice("dev %016llx LU %llx is recovered\n",
 637                                           SAS_ADDR(task->dev),
 638                                           cmd->device->lun);
 639                                 sas_eh_finish_cmd(cmd);
 640                                 sas_scsi_clear_queue_lu(work_q, cmd);
 641                                 goto Again;
 642                         }
 643                         /* fallthrough */
 644                 case TASK_IS_NOT_AT_LU:
 645                 case TASK_ABORT_FAILED:
 646                         pr_notice("task 0x%p is not at LU: I_T recover\n",
 647                                   task);
 648                         tmf_resp = sas_recover_I_T(task->dev);
 649                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
 650                             tmf_resp == -ENODEV) {
 651                                 struct domain_device *dev = task->dev;
 652                                 pr_notice("I_T %016llx recovered\n",
 653                                           SAS_ADDR(task->dev->sas_addr));
 654                                 sas_eh_finish_cmd(cmd);
 655                                 sas_scsi_clear_queue_I_T(work_q, dev);
 656                                 goto Again;
 657                         }
 658                         /* Hammer time :-) */
 659                         try_to_reset_cmd_device(cmd);
 660                         if (i->dft->lldd_clear_nexus_port) {
 661                                 struct asd_sas_port *port = task->dev->port;
 662                                 pr_debug("clearing nexus for port:%d\n",
 663                                           port->id);
 664                                 res = i->dft->lldd_clear_nexus_port(port);
 665                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 666                                         pr_notice("clear nexus port:%d succeeded\n",
 667                                                   port->id);
 668                                         sas_eh_finish_cmd(cmd);
 669                                         sas_scsi_clear_queue_port(work_q,
 670                                                                   port);
 671                                         goto Again;
 672                                 }
 673                         }
 674                         if (i->dft->lldd_clear_nexus_ha) {
 675                                 pr_debug("clear nexus ha\n");
 676                                 res = i->dft->lldd_clear_nexus_ha(ha);
 677                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 678                                         pr_notice("clear nexus ha succeeded\n");
 679                                         sas_eh_finish_cmd(cmd);
 680                                         goto clear_q;
 681                                 }
 682                         }
 683                         /* If we are here -- this means that no amount
 684                          * of effort could recover from errors.  Quite
 685                          * possibly the HA just disappeared.
 686                          */
 687                         pr_err("error from  device %llx, LUN %llx couldn't be recovered in any way\n",
 688                                SAS_ADDR(task->dev->sas_addr),
 689                                cmd->device->lun);
 690
 691                         sas_eh_finish_cmd(cmd);
 692                         goto clear_q;
 693                 }
 694         }
 695  out:
 696         list_splice_tail(&done, work_q);
 697         list_splice_tail_init(&ha->eh_ata_q, work_q);
 698         return;
 699
 700  clear_q:
 701         pr_debug("--- Exit %s -- clear_q\n", __func__);
 702         list_for_each_entry_safe(cmd, n, work_q, eh_entry)
 703                 sas_eh_finish_cmd(cmd);
 704         goto out;
 705 }
 706
 707 static void sas_eh_handle_resets(struct Scsi_Host *shost)
 708 {
 709         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 710         struct sas_internal *i = to_sas_internal(shost->transportt);
 711
 712         /* handle directed resets to sas devices */
 713         spin_lock_irq(&ha->lock);
 714         while (!list_empty(&ha->eh_dev_q)) {
 715                 struct domain_device *dev;
 716                 struct ssp_device *ssp;
 717
 718                 ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
 719                 list_del_init(&ssp->eh_list_node);
 720                 dev = container_of(ssp, typeof(*dev), ssp_dev);
 721                 kref_get(&dev->kref);
 722                 WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
 723
 724                 spin_unlock_irq(&ha->lock);
 725
 726                 if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
 727                         i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
 728
 729                 if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
 730                         i->dft->lldd_I_T_nexus_reset(dev);
 731
 732                 sas_put_device(dev);
 733                 spin_lock_irq(&ha->lock);
 734                 clear_bit(SAS_DEV_EH_PENDING, &dev->state);
 735                 ha->eh_active--;
 736         }
 737         spin_unlock_irq(&ha->lock);
 738 }
 739
 740
 741 void sas_scsi_recover_host(struct Scsi_Host *shost)
 742 {
 743         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 744         LIST_HEAD(eh_work_q);
 745         int tries = 0;
 746         bool retry;
 747
 748 retry:
 749         tries++;
 750         retry = true;
 751         spin_lock_irq(shost->host_lock);
 752         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
 753         spin_unlock_irq(shost->host_lock);
 754
 755         pr_notice("Enter %s busy: %d failed: %d\n",
 756                   __func__, scsi_host_busy(shost), shost->host_failed);
 757         /*
 758          * Deal with commands that still have SAS tasks (i.e. they didn't
 759          * complete via the normal sas_task completion mechanism),
 760          * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
 761          */
 762         set_bit(SAS_HA_FROZEN, &ha->state);
 763         sas_eh_handle_sas_errors(shost, &eh_work_q);
 764         clear_bit(SAS_HA_FROZEN, &ha->state);
 765         if (list_empty(&eh_work_q))
 766                 goto out;
 767
 768         /*
 769          * Now deal with SCSI commands that completed ok but have a an error
 770          * code (and hopefully sense data) attached.  This is roughly what
 771          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
 772          * command we see here has no sas_task and is thus unknown to the HA.
 773          */
 774         sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
 775         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
 776                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
 777
 778 out:
 779         sas_eh_handle_resets(shost);
 780
 781         /* now link into libata eh --- if we have any ata devices */
 782         sas_ata_strategy_handler(shost);
 783
 784         scsi_eh_flush_done_q(&ha->eh_done_q);
 785
 786         /* check if any new eh work was scheduled during the last run */
 787         spin_lock_irq(&ha->lock);
 788         if (ha->eh_active == 0) {
 789                 shost->host_eh_scheduled = 0;
 790                 retry = false;
 791         }
 792         spin_unlock_irq(&ha->lock);
 793
 794         if (retry)
 795                 goto retry;
 796
 797         pr_notice("--- Exit %s: busy: %d failed: %d tries: %d\n",
 798                   __func__, scsi_host_busy(shost),
 799                   shost->host_failed, tries);
 800 }
 801
 802 int sas_ioctl(struct scsi_device *sdev, unsigned int cmd, void __user *arg)
 803 {
 804         struct domain_device *dev = sdev_to_domain_dev(sdev);
 805
 806         if (dev_is_sata(dev))
 807                 return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
 808
 809         return -EINVAL;
 810 }
 811
 812 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
 813 {
 814         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
 815         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 816         struct domain_device *found_dev = NULL;
 817         int i;
 818         unsigned long flags;
 819
 820         spin_lock_irqsave(&ha->phy_port_lock, flags);
 821         for (i = 0; i < ha->num_phys; i++) {
 822                 struct asd_sas_port *port = ha->sas_port[i];
 823                 struct domain_device *dev;
 824
 825                 spin_lock(&port->dev_list_lock);
 826                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
 827                         if (rphy == dev->rphy) {
 828                                 found_dev = dev;
 829                                 spin_unlock(&port->dev_list_lock);
 830                                 goto found;
 831                         }
 832                 }
 833                 spin_unlock(&port->dev_list_lock);
 834         }
 835  found:
 836         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 837
 838         return found_dev;
 839 }
 840
 841 int sas_target_alloc(struct scsi_target *starget)
 842 {
 843         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
 844         struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
 845
 846         if (!found_dev)
 847                 return -ENODEV;
 848
 849         kref_get(&found_dev->kref);
 850         starget->hostdata = found_dev;
 851         return 0;
 852 }
 853
 854 #define SAS_DEF_QD 256
 855
 856 int sas_slave_configure(struct scsi_device *scsi_dev)
 857 {
 858         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 859
 860         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
 861
 862         if (dev_is_sata(dev)) {
 863                 ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
 864                 return 0;
 865         }
 866
 867         sas_read_port_mode_page(scsi_dev);
 868
 869         if (scsi_dev->tagged_supported) {
 870                 scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
 871         } else {
 872                 pr_notice("device %llx, LUN %llx doesn't support TCQ\n",
 873                           SAS_ADDR(dev->sas_addr), scsi_dev->lun);
 874                 scsi_change_queue_depth(scsi_dev, 1);
 875         }
 876
 877         scsi_dev->allow_restart = 1;
 878
 879         return 0;
 880 }
 881
 882 int sas_change_queue_depth(struct scsi_device *sdev, int depth)
 883 {
 884         struct domain_device *dev = sdev_to_domain_dev(sdev);
 885
 886         if (dev_is_sata(dev))
 887                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
 888
 889         if (!sdev->tagged_supported)
 890                 depth = 1;
 891         return scsi_change_queue_depth(sdev, depth);
 892 }
 893
 894 int sas_bios_param(struct scsi_device *scsi_dev,
 895                           struct block_device *bdev,
 896                           sector_t capacity, int *hsc)
 897 {
 898         hsc[0] = 255;
 899         hsc[1] = 63;
 900         sector_div(capacity, 255*63);
 901         hsc[2] = capacity;
 902
 903         return 0;
 904 }
 905
 906 /*
 907  * Tell an upper layer that it needs to initiate an abort for a given task.
 908  * This should only ever be called by an LLDD.
 909  */
 910 void sas_task_abort(struct sas_task *task)
 911 {
 912         struct scsi_cmnd *sc = task->uldd_task;
 913
 914         /* Escape for libsas internal commands */
 915         if (!sc) {
 916                 struct sas_task_slow *slow = task->slow_task;
 917
 918                 if (!slow)
 919                         return;
 920                 if (!del_timer(&slow->timer))
 921                         return;
 922                 slow->timer.function(&slow->timer);
 923                 return;
 924         }
 925
 926         if (dev_is_sata(task->dev))
 927                 sas_ata_task_abort(task);
 928         else
 929                 blk_abort_request(sc->request);
 930 }
 931
 932 void sas_target_destroy(struct scsi_target *starget)
 933 {
 934         struct domain_device *found_dev = starget->hostdata;
 935
 936         if (!found_dev)
 937                 return;
 938
 939         starget->hostdata = NULL;
 940         sas_put_device(found_dev);
 941 }
 942
 943 #define SAS_STRING_ADDR_SIZE    16
 944
 945 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
 946 {
 947         int res;
 948         const struct firmware *fw;
 949
 950         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
 951         if (res)
 952                 return res;
 953
 954         if (fw->size < SAS_STRING_ADDR_SIZE) {
 955                 res = -ENODEV;
 956                 goto out;
 957         }
 958
 959         res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
 960         if (res)
 961                 goto out;
 962
 963 out:
 964         release_firmware(fw);
 965         return res;
 966 }
 967 EXPORT_SYMBOL_GPL(sas_request_addr);
 968
 969 EXPORT_SYMBOL_GPL(sas_queuecommand);
 970 EXPORT_SYMBOL_GPL(sas_target_alloc);
 971 EXPORT_SYMBOL_GPL(sas_slave_configure);
 972 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
 973 EXPORT_SYMBOL_GPL(sas_bios_param);
 974 EXPORT_SYMBOL_GPL(sas_task_abort);
 975 EXPORT_SYMBOL_GPL(sas_phy_reset);
 976 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
 977 EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
 978 EXPORT_SYMBOL_GPL(sas_target_destroy);
 979 EXPORT_SYMBOL_GPL(sas_ioctl);