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 <luben_tuikov@adaptec.com>
   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                         SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
  97                                     "task; please report this\n",
  98                                     task->dev->port->ha->sas_ha_name);
  99                         break;
 100                 case SAS_ABORTED_TASK:
 101                         hs = DID_ABORT;
 102                         break;
 103                 case SAM_STAT_CHECK_CONDITION:
 104                         memcpy(sc->sense_buffer, ts->buf,
 105                                min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
 106                         stat = SAM_STAT_CHECK_CONDITION;
 107                         break;
 108                 default:
 109                         stat = ts->stat;
 110                         break;
 111                 }
 112         }
 113
 114         sc->result = (hs << 16) | stat;
 115         ASSIGN_SAS_TASK(sc, NULL);
 116         sas_free_task(task);
 117 }
 118
 119 static void sas_scsi_task_done(struct sas_task *task)
 120 {
 121         struct scsi_cmnd *sc = task->uldd_task;
 122         struct domain_device *dev = task->dev;
 123         struct sas_ha_struct *ha = dev->port->ha;
 124         unsigned long flags;
 125
 126         spin_lock_irqsave(&dev->done_lock, flags);
 127         if (test_bit(SAS_HA_FROZEN, &ha->state))
 128                 task = NULL;
 129         else
 130                 ASSIGN_SAS_TASK(sc, NULL);
 131         spin_unlock_irqrestore(&dev->done_lock, flags);
 132
 133         if (unlikely(!task)) {
 134                 /* task will be completed by the error handler */
 135                 SAS_DPRINTK("task done but aborted\n");
 136                 return;
 137         }
 138
 139         if (unlikely(!sc)) {
 140                 SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
 141                 sas_free_task(task);
 142                 return;
 143         }
 144
 145         sas_end_task(sc, task);
 146         sc->scsi_done(sc);
 147 }
 148
 149 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 150                                                struct domain_device *dev,
 151                                                gfp_t gfp_flags)
 152 {
 153         struct sas_task *task = sas_alloc_task(gfp_flags);
 154         struct scsi_lun lun;
 155
 156         if (!task)
 157                 return NULL;
 158
 159         task->uldd_task = cmd;
 160         ASSIGN_SAS_TASK(cmd, task);
 161
 162         task->dev = dev;
 163         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
 164
 165         task->ssp_task.retry_count = 1;
 166         int_to_scsilun(cmd->device->lun, &lun);
 167         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
 168         task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
 169         task->ssp_task.cmd = cmd;
 170
 171         task->scatter = scsi_sglist(cmd);
 172         task->num_scatter = scsi_sg_count(cmd);
 173         task->total_xfer_len = scsi_bufflen(cmd);
 174         task->data_dir = cmd->sc_data_direction;
 175
 176         task->task_done = sas_scsi_task_done;
 177
 178         return task;
 179 }
 180
 181 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 182 {
 183         struct sas_internal *i = to_sas_internal(host->transportt);
 184         struct domain_device *dev = cmd_to_domain_dev(cmd);
 185         struct sas_task *task;
 186         int res = 0;
 187
 188         /* If the device fell off, no sense in issuing commands */
 189         if (test_bit(SAS_DEV_GONE, &dev->state)) {
 190                 cmd->result = DID_BAD_TARGET << 16;
 191                 goto out_done;
 192         }
 193
 194         if (dev_is_sata(dev)) {
 195                 spin_lock_irq(dev->sata_dev.ap->lock);
 196                 res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
 197                 spin_unlock_irq(dev->sata_dev.ap->lock);
 198                 return res;
 199         }
 200
 201         task = sas_create_task(cmd, dev, GFP_ATOMIC);
 202         if (!task)
 203                 return SCSI_MLQUEUE_HOST_BUSY;
 204
 205         res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
 206         if (res)
 207                 goto out_free_task;
 208         return 0;
 209
 210 out_free_task:
 211         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
 212         ASSIGN_SAS_TASK(cmd, NULL);
 213         sas_free_task(task);
 214         if (res == -SAS_QUEUE_FULL)
 215                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
 216         else
 217                 cmd->result = DID_ERROR << 16;
 218 out_done:
 219         cmd->scsi_done(cmd);
 220         return 0;
 221 }
 222
 223 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
 224 {
 225         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
 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         /* now finish the command and move it on to the error
 235          * handler done list, this also takes it off the
 236          * error handler pending list.
 237          */
 238         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
 239 }
 240
 241 static void sas_eh_defer_cmd(struct scsi_cmnd *cmd)
 242 {
 243         struct domain_device *dev = cmd_to_domain_dev(cmd);
 244         struct sas_ha_struct *ha = dev->port->ha;
 245         struct sas_task *task = TO_SAS_TASK(cmd);
 246
 247         if (!dev_is_sata(dev)) {
 248                 sas_eh_finish_cmd(cmd);
 249                 return;
 250         }
 251
 252         /* report the timeout to libata */
 253         sas_end_task(cmd, task);
 254         list_move_tail(&cmd->eh_entry, &ha->eh_ata_q);
 255 }
 256
 257 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 258 {
 259         struct scsi_cmnd *cmd, *n;
 260
 261         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 262                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
 263                     cmd->device->lun == my_cmd->device->lun)
 264                         sas_eh_defer_cmd(cmd);
 265         }
 266 }
 267
 268 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 269                                      struct domain_device *dev)
 270 {
 271         struct scsi_cmnd *cmd, *n;
 272
 273         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 274                 struct domain_device *x = cmd_to_domain_dev(cmd);
 275
 276                 if (x == dev)
 277                         sas_eh_finish_cmd(cmd);
 278         }
 279 }
 280
 281 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 282                                       struct asd_sas_port *port)
 283 {
 284         struct scsi_cmnd *cmd, *n;
 285
 286         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 287                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 288                 struct asd_sas_port *x = dev->port;
 289
 290                 if (x == port)
 291                         sas_eh_finish_cmd(cmd);
 292         }
 293 }
 294
 295 enum task_disposition {
 296         TASK_IS_DONE,
 297         TASK_IS_ABORTED,
 298         TASK_IS_AT_LU,
 299         TASK_IS_NOT_AT_LU,
 300         TASK_ABORT_FAILED,
 301 };
 302
 303 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 304 {
 305         unsigned long flags;
 306         int i, res;
 307         struct sas_internal *si =
 308                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 309
 310         for (i = 0; i < 5; i++) {
 311                 SAS_DPRINTK("%s: aborting task 0x%p\n", __func__, task);
 312                 res = si->dft->lldd_abort_task(task);
 313
 314                 spin_lock_irqsave(&task->task_state_lock, flags);
 315                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 316                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 317                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
 318                                     task);
 319                         return TASK_IS_DONE;
 320                 }
 321                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 322
 323                 if (res == TMF_RESP_FUNC_COMPLETE) {
 324                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 325                                     __func__, task);
 326                         return TASK_IS_ABORTED;
 327                 } else if (si->dft->lldd_query_task) {
 328                         SAS_DPRINTK("%s: querying task 0x%p\n",
 329                                     __func__, task);
 330                         res = si->dft->lldd_query_task(task);
 331                         switch (res) {
 332                         case TMF_RESP_FUNC_SUCC:
 333                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
 334                                             __func__, task);
 335                                 return TASK_IS_AT_LU;
 336                         case TMF_RESP_FUNC_COMPLETE:
 337                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
 338                                             __func__, task);
 339                                 return TASK_IS_NOT_AT_LU;
 340                         case TMF_RESP_FUNC_FAILED:
 341                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
 342                                                 __func__, task);
 343                                 return TASK_ABORT_FAILED;
 344                         }
 345
 346                 }
 347         }
 348         return res;
 349 }
 350
 351 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 352 {
 353         int res = TMF_RESP_FUNC_FAILED;
 354         struct scsi_lun lun;
 355         struct sas_internal *i =
 356                 to_sas_internal(dev->port->ha->core.shost->transportt);
 357
 358         int_to_scsilun(cmd->device->lun, &lun);
 359
 360         SAS_DPRINTK("eh: device %llx LUN %llx has the task\n",
 361                     SAS_ADDR(dev->sas_addr),
 362                     cmd->device->lun);
 363
 364         if (i->dft->lldd_abort_task_set)
 365                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 366
 367         if (res == TMF_RESP_FUNC_FAILED) {
 368                 if (i->dft->lldd_clear_task_set)
 369                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 370         }
 371
 372         if (res == TMF_RESP_FUNC_FAILED) {
 373                 if (i->dft->lldd_lu_reset)
 374                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 375         }
 376
 377         return res;
 378 }
 379
 380 static int sas_recover_I_T(struct domain_device *dev)
 381 {
 382         int res = TMF_RESP_FUNC_FAILED;
 383         struct sas_internal *i =
 384                 to_sas_internal(dev->port->ha->core.shost->transportt);
 385
 386         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
 387                     SAS_ADDR(dev->sas_addr));
 388
 389         if (i->dft->lldd_I_T_nexus_reset)
 390                 res = i->dft->lldd_I_T_nexus_reset(dev);
 391
 392         return res;
 393 }
 394
 395 /* take a reference on the last known good phy for this device */
 396 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
 397 {
 398         struct sas_ha_struct *ha = dev->port->ha;
 399         struct sas_phy *phy;
 400         unsigned long flags;
 401
 402         /* a published domain device always has a valid phy, it may be
 403          * stale, but it is never NULL
 404          */
 405         BUG_ON(!dev->phy);
 406
 407         spin_lock_irqsave(&ha->phy_port_lock, flags);
 408         phy = dev->phy;
 409         get_device(&phy->dev);
 410         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 411
 412         return phy;
 413 }
 414 EXPORT_SYMBOL_GPL(sas_get_local_phy);
 415
 416 static void sas_wait_eh(struct domain_device *dev)
 417 {
 418         struct sas_ha_struct *ha = dev->port->ha;
 419         DEFINE_WAIT(wait);
 420
 421         if (dev_is_sata(dev)) {
 422                 ata_port_wait_eh(dev->sata_dev.ap);
 423                 return;
 424         }
 425  retry:
 426         spin_lock_irq(&ha->lock);
 427
 428         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
 429                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 430                 spin_unlock_irq(&ha->lock);
 431                 schedule();
 432                 spin_lock_irq(&ha->lock);
 433         }
 434         finish_wait(&ha->eh_wait_q, &wait);
 435
 436         spin_unlock_irq(&ha->lock);
 437
 438         /* make sure SCSI EH is complete */
 439         if (scsi_host_in_recovery(ha->core.shost)) {
 440                 msleep(10);
 441                 goto retry;
 442         }
 443 }
 444 EXPORT_SYMBOL(sas_wait_eh);
 445
 446 static int sas_queue_reset(struct domain_device *dev, int reset_type,
 447                            u64 lun, int wait)
 448 {
 449         struct sas_ha_struct *ha = dev->port->ha;
 450         int scheduled = 0, tries = 100;
 451
 452         /* ata: promote lun reset to bus reset */
 453         if (dev_is_sata(dev)) {
 454                 sas_ata_schedule_reset(dev);
 455                 if (wait)
 456                         sas_ata_wait_eh(dev);
 457                 return SUCCESS;
 458         }
 459
 460         while (!scheduled && tries--) {
 461                 spin_lock_irq(&ha->lock);
 462                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
 463                     !test_bit(reset_type, &dev->state)) {
 464                         scheduled = 1;
 465                         ha->eh_active++;
 466                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
 467                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
 468                         set_bit(reset_type, &dev->state);
 469                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
 470                         scsi_schedule_eh(ha->core.shost);
 471                 }
 472                 spin_unlock_irq(&ha->lock);
 473
 474                 if (wait)
 475                         sas_wait_eh(dev);
 476
 477                 if (scheduled)
 478                         return SUCCESS;
 479         }
 480
 481         SAS_DPRINTK("%s reset of %s failed\n",
 482                     reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
 483                     dev_name(&dev->rphy->dev));
 484
 485         return FAILED;
 486 }
 487
 488 int sas_eh_abort_handler(struct scsi_cmnd *cmd)
 489 {
 490         int res;
 491         struct sas_task *task = TO_SAS_TASK(cmd);
 492         struct Scsi_Host *host = cmd->device->host;
 493         struct sas_internal *i = to_sas_internal(host->transportt);
 494
 495         if (!i->dft->lldd_abort_task)
 496                 return FAILED;
 497
 498         res = i->dft->lldd_abort_task(task);
 499         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 500                 return SUCCESS;
 501
 502         return FAILED;
 503 }
 504 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
 505
 506 /* Attempt to send a LUN reset message to a device */
 507 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 508 {
 509         int res;
 510         struct scsi_lun lun;
 511         struct Scsi_Host *host = cmd->device->host;
 512         struct domain_device *dev = cmd_to_domain_dev(cmd);
 513         struct sas_internal *i = to_sas_internal(host->transportt);
 514
 515         if (current != host->ehandler)
 516                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
 517
 518         int_to_scsilun(cmd->device->lun, &lun);
 519
 520         if (!i->dft->lldd_lu_reset)
 521                 return FAILED;
 522
 523         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 524         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 525                 return SUCCESS;
 526
 527         return FAILED;
 528 }
 529
 530 int sas_eh_target_reset_handler(struct scsi_cmnd *cmd)
 531 {
 532         int res;
 533         struct Scsi_Host *host = cmd->device->host;
 534         struct domain_device *dev = cmd_to_domain_dev(cmd);
 535         struct sas_internal *i = to_sas_internal(host->transportt);
 536
 537         if (current != host->ehandler)
 538                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
 539
 540         if (!i->dft->lldd_I_T_nexus_reset)
 541                 return FAILED;
 542
 543         res = i->dft->lldd_I_T_nexus_reset(dev);
 544         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
 545             res == -ENODEV)
 546                 return SUCCESS;
 547
 548         return FAILED;
 549 }
 550
 551 /* Try to reset a device */
 552 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
 553 {
 554         int res;
 555         struct Scsi_Host *shost = cmd->device->host;
 556
 557         if (!shost->hostt->eh_device_reset_handler)
 558                 goto try_target_reset;
 559
 560         res = shost->hostt->eh_device_reset_handler(cmd);
 561         if (res == SUCCESS)
 562                 return res;
 563
 564 try_target_reset:
 565         if (shost->hostt->eh_target_reset_handler)
 566                 return shost->hostt->eh_target_reset_handler(cmd);
 567
 568         return FAILED;
 569 }
 570
 571 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
 572 {
 573         struct scsi_cmnd *cmd, *n;
 574         enum task_disposition res = TASK_IS_DONE;
 575         int tmf_resp, need_reset;
 576         struct sas_internal *i = to_sas_internal(shost->transportt);
 577         unsigned long flags;
 578         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 579         LIST_HEAD(done);
 580
 581         /* clean out any commands that won the completion vs eh race */
 582         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 583                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 584                 struct sas_task *task;
 585
 586                 spin_lock_irqsave(&dev->done_lock, flags);
 587                 /* by this point the lldd has either observed
 588                  * SAS_HA_FROZEN and is leaving the task alone, or has
 589                  * won the race with eh and decided to complete it
 590                  */
 591                 task = TO_SAS_TASK(cmd);
 592                 spin_unlock_irqrestore(&dev->done_lock, flags);
 593
 594                 if (!task)
 595                         list_move_tail(&cmd->eh_entry, &done);
 596         }
 597
 598  Again:
 599         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 600                 struct sas_task *task = TO_SAS_TASK(cmd);
 601
 602                 list_del_init(&cmd->eh_entry);
 603
 604                 spin_lock_irqsave(&task->task_state_lock, flags);
 605                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 606                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 607
 608                 if (need_reset) {
 609                         SAS_DPRINTK("%s: task 0x%p requests reset\n",
 610                                     __func__, task);
 611                         goto reset;
 612                 }
 613
 614                 SAS_DPRINTK("trying to find task 0x%p\n", task);
 615                 res = sas_scsi_find_task(task);
 616
 617                 switch (res) {
 618                 case TASK_IS_DONE:
 619                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
 620                                     task);
 621                         sas_eh_defer_cmd(cmd);
 622                         continue;
 623                 case TASK_IS_ABORTED:
 624                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 625                                     __func__, task);
 626                         sas_eh_defer_cmd(cmd);
 627                         continue;
 628                 case TASK_IS_AT_LU:
 629                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
 630  reset:
 631                         tmf_resp = sas_recover_lu(task->dev, cmd);
 632                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 633                                 SAS_DPRINTK("dev %016llx LU %llx is "
 634                                             "recovered\n",
 635                                             SAS_ADDR(task->dev),
 636                                             cmd->device->lun);
 637                                 sas_eh_defer_cmd(cmd);
 638                                 sas_scsi_clear_queue_lu(work_q, cmd);
 639                                 goto Again;
 640                         }
 641                         /* fallthrough */
 642                 case TASK_IS_NOT_AT_LU:
 643                 case TASK_ABORT_FAILED:
 644                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
 645                                     task);
 646                         tmf_resp = sas_recover_I_T(task->dev);
 647                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
 648                             tmf_resp == -ENODEV) {
 649                                 struct domain_device *dev = task->dev;
 650                                 SAS_DPRINTK("I_T %016llx recovered\n",
 651                                             SAS_ADDR(task->dev->sas_addr));
 652                                 sas_eh_finish_cmd(cmd);
 653                                 sas_scsi_clear_queue_I_T(work_q, dev);
 654                                 goto Again;
 655                         }
 656                         /* Hammer time :-) */
 657                         try_to_reset_cmd_device(cmd);
 658                         if (i->dft->lldd_clear_nexus_port) {
 659                                 struct asd_sas_port *port = task->dev->port;
 660                                 SAS_DPRINTK("clearing nexus for port:%d\n",
 661                                             port->id);
 662                                 res = i->dft->lldd_clear_nexus_port(port);
 663                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 664                                         SAS_DPRINTK("clear nexus port:%d "
 665                                                     "succeeded\n", port->id);
 666                                         sas_eh_finish_cmd(cmd);
 667                                         sas_scsi_clear_queue_port(work_q,
 668                                                                   port);
 669                                         goto Again;
 670                                 }
 671                         }
 672                         if (i->dft->lldd_clear_nexus_ha) {
 673                                 SAS_DPRINTK("clear nexus ha\n");
 674                                 res = i->dft->lldd_clear_nexus_ha(ha);
 675                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 676                                         SAS_DPRINTK("clear nexus ha "
 677                                                     "succeeded\n");
 678                                         sas_eh_finish_cmd(cmd);
 679                                         goto clear_q;
 680                                 }
 681                         }
 682                         /* If we are here -- this means that no amount
 683                          * of effort could recover from errors.  Quite
 684                          * possibly the HA just disappeared.
 685                          */
 686                         SAS_DPRINTK("error from  device %llx, LUN %llx "
 687                                     "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         SAS_DPRINTK("--- 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         SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
 756                     __func__, atomic_read(&shost->host_busy), 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         SAS_DPRINTK("--- Exit %s: busy: %d failed: %d tries: %d\n",
 798                     __func__, atomic_read(&shost->host_busy),
 799                     shost->host_failed, tries);
 800 }
 801
 802 int sas_ioctl(struct scsi_device *sdev, 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                 SAS_DPRINTK("device %llx, LUN %llx doesn't support "
 873                             "TCQ\n", SAS_ADDR(dev->sas_addr),
 874                             scsi_dev->lun);
 875                 scsi_change_queue_depth(scsi_dev, 1);
 876         }
 877
 878         scsi_dev->allow_restart = 1;
 879
 880         return 0;
 881 }
 882
 883 int sas_change_queue_depth(struct scsi_device *sdev, int depth)
 884 {
 885         struct domain_device *dev = sdev_to_domain_dev(sdev);
 886
 887         if (dev_is_sata(dev))
 888                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
 889
 890         if (!sdev->tagged_supported)
 891                 depth = 1;
 892         return scsi_change_queue_depth(sdev, depth);
 893 }
 894
 895 int sas_bios_param(struct scsi_device *scsi_dev,
 896                           struct block_device *bdev,
 897                           sector_t capacity, int *hsc)
 898 {
 899         hsc[0] = 255;
 900         hsc[1] = 63;
 901         sector_div(capacity, 255*63);
 902         hsc[2] = capacity;
 903
 904         return 0;
 905 }
 906
 907 /*
 908  * Tell an upper layer that it needs to initiate an abort for a given task.
 909  * This should only ever be called by an LLDD.
 910  */
 911 void sas_task_abort(struct sas_task *task)
 912 {
 913         struct scsi_cmnd *sc = task->uldd_task;
 914
 915         /* Escape for libsas internal commands */
 916         if (!sc) {
 917                 struct sas_task_slow *slow = task->slow_task;
 918
 919                 if (!slow)
 920                         return;
 921                 if (!del_timer(&slow->timer))
 922                         return;
 923                 slow->timer.function(&slow->timer);
 924                 return;
 925         }
 926
 927         if (dev_is_sata(task->dev)) {
 928                 sas_ata_task_abort(task);
 929         } else {
 930                 struct request_queue *q = sc->device->request_queue;
 931                 unsigned long flags;
 932
 933                 spin_lock_irqsave(q->queue_lock, flags);
 934                 blk_abort_request(sc->request);
 935                 spin_unlock_irqrestore(q->queue_lock, flags);
 936         }
 937 }
 938
 939 void sas_target_destroy(struct scsi_target *starget)
 940 {
 941         struct domain_device *found_dev = starget->hostdata;
 942
 943         if (!found_dev)
 944                 return;
 945
 946         starget->hostdata = NULL;
 947         sas_put_device(found_dev);
 948 }
 949
 950 #define SAS_STRING_ADDR_SIZE    16
 951
 952 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
 953 {
 954         int res;
 955         const struct firmware *fw;
 956
 957         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
 958         if (res)
 959                 return res;
 960
 961         if (fw->size < SAS_STRING_ADDR_SIZE) {
 962                 res = -ENODEV;
 963                 goto out;
 964         }
 965
 966         res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
 967         if (res)
 968                 goto out;
 969
 970 out:
 971         release_firmware(fw);
 972         return res;
 973 }
 974 EXPORT_SYMBOL_GPL(sas_request_addr);
 975
 976 EXPORT_SYMBOL_GPL(sas_queuecommand);
 977 EXPORT_SYMBOL_GPL(sas_target_alloc);
 978 EXPORT_SYMBOL_GPL(sas_slave_configure);
 979 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
 980 EXPORT_SYMBOL_GPL(sas_bios_param);
 981 EXPORT_SYMBOL_GPL(sas_task_abort);
 982 EXPORT_SYMBOL_GPL(sas_phy_reset);
 983 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
 984 EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
 985 EXPORT_SYMBOL_GPL(sas_target_destroy);
 986 EXPORT_SYMBOL_GPL(sas_ioctl);