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
  31 #include "sas_internal.h"
  32
  33 #include <scsi/scsi_host.h>
  34 #include <scsi/scsi_device.h>
  35 #include <scsi/scsi_tcq.h>
  36 #include <scsi/scsi.h>
  37 #include <scsi/scsi_eh.h>
  38 #include <scsi/scsi_transport.h>
  39 #include <scsi/scsi_transport_sas.h>
  40 #include <scsi/sas_ata.h>
  41 #include "../scsi_sas_internal.h"
  42 #include "../scsi_transport_api.h"
  43 #include "../scsi_priv.h"
  44
  45 #include <linux/err.h>
  46 #include <linux/blkdev.h>
  47 #include <linux/freezer.h>
  48 #include <linux/gfp.h>
  49 #include <linux/scatterlist.h>
  50 #include <linux/libata.h>
  51
  52 /* record final status and free the task */
  53 static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
  54 {
  55         struct task_status_struct *ts = &task->task_status;
  56         int hs = 0, stat = 0;
  57
  58         if (ts->resp == SAS_TASK_UNDELIVERED) {
  59                 /* transport error */
  60                 hs = DID_NO_CONNECT;
  61         } else { /* ts->resp == SAS_TASK_COMPLETE */
  62                 /* task delivered, what happened afterwards? */
  63                 switch (ts->stat) {
  64                 case SAS_DEV_NO_RESPONSE:
  65                 case SAS_INTERRUPTED:
  66                 case SAS_PHY_DOWN:
  67                 case SAS_NAK_R_ERR:
  68                 case SAS_OPEN_TO:
  69                         hs = DID_NO_CONNECT;
  70                         break;
  71                 case SAS_DATA_UNDERRUN:
  72                         scsi_set_resid(sc, ts->residual);
  73                         if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
  74                                 hs = DID_ERROR;
  75                         break;
  76                 case SAS_DATA_OVERRUN:
  77                         hs = DID_ERROR;
  78                         break;
  79                 case SAS_QUEUE_FULL:
  80                         hs = DID_SOFT_ERROR; /* retry */
  81                         break;
  82                 case SAS_DEVICE_UNKNOWN:
  83                         hs = DID_BAD_TARGET;
  84                         break;
  85                 case SAS_SG_ERR:
  86                         hs = DID_PARITY;
  87                         break;
  88                 case SAS_OPEN_REJECT:
  89                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
  90                                 hs = DID_SOFT_ERROR; /* retry */
  91                         else
  92                                 hs = DID_ERROR;
  93                         break;
  94                 case SAS_PROTO_RESPONSE:
  95                         SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
  96                                     "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         list_del_init(&task->list);
 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                 list_del_init(&task->list);
 142                 sas_free_task(task);
 143                 return;
 144         }
 145
 146         sas_end_task(sc, task);
 147         sc->scsi_done(sc);
 148 }
 149
 150 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 151                                                struct domain_device *dev,
 152                                                gfp_t gfp_flags)
 153 {
 154         struct sas_task *task = sas_alloc_task(gfp_flags);
 155         struct scsi_lun lun;
 156
 157         if (!task)
 158                 return NULL;
 159
 160         task->uldd_task = cmd;
 161         ASSIGN_SAS_TASK(cmd, task);
 162
 163         task->dev = dev;
 164         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
 165
 166         task->ssp_task.retry_count = 1;
 167         int_to_scsilun(cmd->device->lun, &lun);
 168         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
 169         task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
 170         memcpy(task->ssp_task.cdb, cmd->cmnd, 16);
 171
 172         task->scatter = scsi_sglist(cmd);
 173         task->num_scatter = scsi_sg_count(cmd);
 174         task->total_xfer_len = scsi_bufflen(cmd);
 175         task->data_dir = cmd->sc_data_direction;
 176
 177         task->task_done = sas_scsi_task_done;
 178
 179         return task;
 180 }
 181
 182 int sas_queue_up(struct sas_task *task)
 183 {
 184         struct sas_ha_struct *sas_ha = task->dev->port->ha;
 185         struct scsi_core *core = &sas_ha->core;
 186         unsigned long flags;
 187         LIST_HEAD(list);
 188
 189         spin_lock_irqsave(&core->task_queue_lock, flags);
 190         if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
 191                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 192                 return -SAS_QUEUE_FULL;
 193         }
 194         list_add_tail(&task->list, &core->task_queue);
 195         core->task_queue_size += 1;
 196         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 197         wake_up_process(core->queue_thread);
 198
 199         return 0;
 200 }
 201
 202 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 203 {
 204         struct sas_internal *i = to_sas_internal(host->transportt);
 205         struct domain_device *dev = cmd_to_domain_dev(cmd);
 206         struct sas_ha_struct *sas_ha = dev->port->ha;
 207         struct sas_task *task;
 208         int res = 0;
 209
 210         /* If the device fell off, no sense in issuing commands */
 211         if (test_bit(SAS_DEV_GONE, &dev->state)) {
 212                 cmd->result = DID_BAD_TARGET << 16;
 213                 goto out_done;
 214         }
 215
 216         if (dev_is_sata(dev)) {
 217                 spin_lock_irq(dev->sata_dev.ap->lock);
 218                 res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
 219                 spin_unlock_irq(dev->sata_dev.ap->lock);
 220                 return res;
 221         }
 222
 223         task = sas_create_task(cmd, dev, GFP_ATOMIC);
 224         if (!task)
 225                 return SCSI_MLQUEUE_HOST_BUSY;
 226
 227         /* Queue up, Direct Mode or Task Collector Mode. */
 228         if (sas_ha->lldd_max_execute_num < 2)
 229                 res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
 230         else
 231                 res = sas_queue_up(task);
 232
 233         if (res)
 234                 goto out_free_task;
 235         return 0;
 236
 237 out_free_task:
 238         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
 239         ASSIGN_SAS_TASK(cmd, NULL);
 240         sas_free_task(task);
 241         if (res == -SAS_QUEUE_FULL)
 242                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
 243         else
 244                 cmd->result = DID_ERROR << 16;
 245 out_done:
 246         cmd->scsi_done(cmd);
 247         return 0;
 248 }
 249
 250 static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
 251 {
 252         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
 253         struct sas_task *task = TO_SAS_TASK(cmd);
 254
 255         /* At this point, we only get called following an actual abort
 256          * of the task, so we should be guaranteed not to be racing with
 257          * any completions from the LLD.  Task is freed after this.
 258          */
 259         sas_end_task(cmd, task);
 260
 261         /* now finish the command and move it on to the error
 262          * handler done list, this also takes it off the
 263          * error handler pending list.
 264          */
 265         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
 266 }
 267
 268 static void sas_eh_defer_cmd(struct scsi_cmnd *cmd)
 269 {
 270         struct domain_device *dev = cmd_to_domain_dev(cmd);
 271         struct sas_ha_struct *ha = dev->port->ha;
 272         struct sas_task *task = TO_SAS_TASK(cmd);
 273
 274         if (!dev_is_sata(dev)) {
 275                 sas_eh_finish_cmd(cmd);
 276                 return;
 277         }
 278
 279         /* report the timeout to libata */
 280         sas_end_task(cmd, task);
 281         list_move_tail(&cmd->eh_entry, &ha->eh_ata_q);
 282 }
 283
 284 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 285 {
 286         struct scsi_cmnd *cmd, *n;
 287
 288         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 289                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
 290                     cmd->device->lun == my_cmd->device->lun)
 291                         sas_eh_defer_cmd(cmd);
 292         }
 293 }
 294
 295 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 296                                      struct domain_device *dev)
 297 {
 298         struct scsi_cmnd *cmd, *n;
 299
 300         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 301                 struct domain_device *x = cmd_to_domain_dev(cmd);
 302
 303                 if (x == dev)
 304                         sas_eh_finish_cmd(cmd);
 305         }
 306 }
 307
 308 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 309                                       struct asd_sas_port *port)
 310 {
 311         struct scsi_cmnd *cmd, *n;
 312
 313         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 314                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 315                 struct asd_sas_port *x = dev->port;
 316
 317                 if (x == port)
 318                         sas_eh_finish_cmd(cmd);
 319         }
 320 }
 321
 322 enum task_disposition {
 323         TASK_IS_DONE,
 324         TASK_IS_ABORTED,
 325         TASK_IS_AT_LU,
 326         TASK_IS_NOT_AT_HA,
 327         TASK_IS_NOT_AT_LU,
 328         TASK_ABORT_FAILED,
 329 };
 330
 331 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 332 {
 333         struct sas_ha_struct *ha = task->dev->port->ha;
 334         unsigned long flags;
 335         int i, res;
 336         struct sas_internal *si =
 337                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 338
 339         if (ha->lldd_max_execute_num > 1) {
 340                 struct scsi_core *core = &ha->core;
 341                 struct sas_task *t, *n;
 342
 343                 mutex_lock(&core->task_queue_flush);
 344                 spin_lock_irqsave(&core->task_queue_lock, flags);
 345                 list_for_each_entry_safe(t, n, &core->task_queue, list)
 346                         if (task == t) {
 347                                 list_del_init(&t->list);
 348                                 break;
 349                         }
 350                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 351                 mutex_unlock(&core->task_queue_flush);
 352
 353                 if (task == t)
 354                         return TASK_IS_NOT_AT_HA;
 355         }
 356
 357         for (i = 0; i < 5; i++) {
 358                 SAS_DPRINTK("%s: aborting task 0x%p\n", __func__, task);
 359                 res = si->dft->lldd_abort_task(task);
 360
 361                 spin_lock_irqsave(&task->task_state_lock, flags);
 362                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 363                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 364                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
 365                                     task);
 366                         return TASK_IS_DONE;
 367                 }
 368                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 369
 370                 if (res == TMF_RESP_FUNC_COMPLETE) {
 371                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 372                                     __func__, task);
 373                         return TASK_IS_ABORTED;
 374                 } else if (si->dft->lldd_query_task) {
 375                         SAS_DPRINTK("%s: querying task 0x%p\n",
 376                                     __func__, task);
 377                         res = si->dft->lldd_query_task(task);
 378                         switch (res) {
 379                         case TMF_RESP_FUNC_SUCC:
 380                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
 381                                             __func__, task);
 382                                 return TASK_IS_AT_LU;
 383                         case TMF_RESP_FUNC_COMPLETE:
 384                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
 385                                             __func__, task);
 386                                 return TASK_IS_NOT_AT_LU;
 387                         case TMF_RESP_FUNC_FAILED:
 388                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
 389                                                 __func__, task);
 390                                 return TASK_ABORT_FAILED;
 391                         }
 392
 393                 }
 394         }
 395         return res;
 396 }
 397
 398 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 399 {
 400         int res = TMF_RESP_FUNC_FAILED;
 401         struct scsi_lun lun;
 402         struct sas_internal *i =
 403                 to_sas_internal(dev->port->ha->core.shost->transportt);
 404
 405         int_to_scsilun(cmd->device->lun, &lun);
 406
 407         SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
 408                     SAS_ADDR(dev->sas_addr),
 409                     cmd->device->lun);
 410
 411         if (i->dft->lldd_abort_task_set)
 412                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 413
 414         if (res == TMF_RESP_FUNC_FAILED) {
 415                 if (i->dft->lldd_clear_task_set)
 416                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 417         }
 418
 419         if (res == TMF_RESP_FUNC_FAILED) {
 420                 if (i->dft->lldd_lu_reset)
 421                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 422         }
 423
 424         return res;
 425 }
 426
 427 static int sas_recover_I_T(struct domain_device *dev)
 428 {
 429         int res = TMF_RESP_FUNC_FAILED;
 430         struct sas_internal *i =
 431                 to_sas_internal(dev->port->ha->core.shost->transportt);
 432
 433         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
 434                     SAS_ADDR(dev->sas_addr));
 435
 436         if (i->dft->lldd_I_T_nexus_reset)
 437                 res = i->dft->lldd_I_T_nexus_reset(dev);
 438
 439         return res;
 440 }
 441
 442 /* take a reference on the last known good phy for this device */
 443 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
 444 {
 445         struct sas_ha_struct *ha = dev->port->ha;
 446         struct sas_phy *phy;
 447         unsigned long flags;
 448
 449         /* a published domain device always has a valid phy, it may be
 450          * stale, but it is never NULL
 451          */
 452         BUG_ON(!dev->phy);
 453
 454         spin_lock_irqsave(&ha->phy_port_lock, flags);
 455         phy = dev->phy;
 456         get_device(&phy->dev);
 457         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 458
 459         return phy;
 460 }
 461 EXPORT_SYMBOL_GPL(sas_get_local_phy);
 462
 463 static void sas_wait_eh(struct domain_device *dev)
 464 {
 465         struct sas_ha_struct *ha = dev->port->ha;
 466         DEFINE_WAIT(wait);
 467
 468         if (dev_is_sata(dev)) {
 469                 ata_port_wait_eh(dev->sata_dev.ap);
 470                 return;
 471         }
 472  retry:
 473         spin_lock_irq(&ha->lock);
 474
 475         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
 476                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 477                 spin_unlock_irq(&ha->lock);
 478                 schedule();
 479                 spin_lock_irq(&ha->lock);
 480         }
 481         finish_wait(&ha->eh_wait_q, &wait);
 482
 483         spin_unlock_irq(&ha->lock);
 484
 485         /* make sure SCSI EH is complete */
 486         if (scsi_host_in_recovery(ha->core.shost)) {
 487                 msleep(10);
 488                 goto retry;
 489         }
 490 }
 491 EXPORT_SYMBOL(sas_wait_eh);
 492
 493 static int sas_queue_reset(struct domain_device *dev, int reset_type, int lun, int wait)
 494 {
 495         struct sas_ha_struct *ha = dev->port->ha;
 496         int scheduled = 0, tries = 100;
 497
 498         /* ata: promote lun reset to bus reset */
 499         if (dev_is_sata(dev)) {
 500                 sas_ata_schedule_reset(dev);
 501                 if (wait)
 502                         sas_ata_wait_eh(dev);
 503                 return SUCCESS;
 504         }
 505
 506         while (!scheduled && tries--) {
 507                 spin_lock_irq(&ha->lock);
 508                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
 509                     !test_bit(reset_type, &dev->state)) {
 510                         scheduled = 1;
 511                         ha->eh_active++;
 512                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
 513                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
 514                         set_bit(reset_type, &dev->state);
 515                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
 516                         scsi_schedule_eh(ha->core.shost);
 517                 }
 518                 spin_unlock_irq(&ha->lock);
 519
 520                 if (wait)
 521                         sas_wait_eh(dev);
 522
 523                 if (scheduled)
 524                         return SUCCESS;
 525         }
 526
 527         SAS_DPRINTK("%s reset of %s failed\n",
 528                     reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
 529                     dev_name(&dev->rphy->dev));
 530
 531         return FAILED;
 532 }
 533
 534 /* Attempt to send a LUN reset message to a device */
 535 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 536 {
 537         int res;
 538         struct scsi_lun lun;
 539         struct Scsi_Host *host = cmd->device->host;
 540         struct domain_device *dev = cmd_to_domain_dev(cmd);
 541         struct sas_internal *i = to_sas_internal(host->transportt);
 542
 543         if (current != host->ehandler)
 544                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
 545
 546         int_to_scsilun(cmd->device->lun, &lun);
 547
 548         if (!i->dft->lldd_lu_reset)
 549                 return FAILED;
 550
 551         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 552         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 553                 return SUCCESS;
 554
 555         return FAILED;
 556 }
 557
 558 /* Attempt to send a phy (bus) reset */
 559 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
 560 {
 561         struct domain_device *dev = cmd_to_domain_dev(cmd);
 562         struct sas_phy *phy = sas_get_local_phy(dev);
 563         struct Scsi_Host *host = cmd->device->host;
 564         int res;
 565
 566         if (current != host->ehandler)
 567                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
 568
 569         res = sas_phy_reset(phy, 1);
 570         if (res)
 571                 SAS_DPRINTK("Bus reset of %s failed 0x%x\n",
 572                             kobject_name(&phy->dev.kobj),
 573                             res);
 574         sas_put_local_phy(phy);
 575
 576         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 577                 return SUCCESS;
 578
 579         return FAILED;
 580 }
 581
 582 /* Try to reset a device */
 583 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
 584 {
 585         int res;
 586         struct Scsi_Host *shost = cmd->device->host;
 587
 588         if (!shost->hostt->eh_device_reset_handler)
 589                 goto try_bus_reset;
 590
 591         res = shost->hostt->eh_device_reset_handler(cmd);
 592         if (res == SUCCESS)
 593                 return res;
 594
 595 try_bus_reset:
 596         if (shost->hostt->eh_bus_reset_handler)
 597                 return shost->hostt->eh_bus_reset_handler(cmd);
 598
 599         return FAILED;
 600 }
 601
 602 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
 603 {
 604         struct scsi_cmnd *cmd, *n;
 605         enum task_disposition res = TASK_IS_DONE;
 606         int tmf_resp, need_reset;
 607         struct sas_internal *i = to_sas_internal(shost->transportt);
 608         unsigned long flags;
 609         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 610         LIST_HEAD(done);
 611
 612         /* clean out any commands that won the completion vs eh race */
 613         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 614                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 615                 struct sas_task *task;
 616
 617                 spin_lock_irqsave(&dev->done_lock, flags);
 618                 /* by this point the lldd has either observed
 619                  * SAS_HA_FROZEN and is leaving the task alone, or has
 620                  * won the race with eh and decided to complete it
 621                  */
 622                 task = TO_SAS_TASK(cmd);
 623                 spin_unlock_irqrestore(&dev->done_lock, flags);
 624
 625                 if (!task)
 626                         list_move_tail(&cmd->eh_entry, &done);
 627         }
 628
 629  Again:
 630         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 631                 struct sas_task *task = TO_SAS_TASK(cmd);
 632
 633                 list_del_init(&cmd->eh_entry);
 634
 635                 spin_lock_irqsave(&task->task_state_lock, flags);
 636                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 637                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 638
 639                 if (need_reset) {
 640                         SAS_DPRINTK("%s: task 0x%p requests reset\n",
 641                                     __func__, task);
 642                         goto reset;
 643                 }
 644
 645                 SAS_DPRINTK("trying to find task 0x%p\n", task);
 646                 res = sas_scsi_find_task(task);
 647
 648                 cmd->eh_eflags = 0;
 649
 650                 switch (res) {
 651                 case TASK_IS_NOT_AT_HA:
 652                         SAS_DPRINTK("%s: task 0x%p is not at ha: %s\n",
 653                                     __func__, task,
 654                                     cmd->retries ? "retry" : "aborted");
 655                         if (cmd->retries)
 656                                 cmd->retries--;
 657                         sas_eh_finish_cmd(cmd);
 658                         continue;
 659                 case TASK_IS_DONE:
 660                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
 661                                     task);
 662                         sas_eh_defer_cmd(cmd);
 663                         continue;
 664                 case TASK_IS_ABORTED:
 665                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 666                                     __func__, task);
 667                         sas_eh_defer_cmd(cmd);
 668                         continue;
 669                 case TASK_IS_AT_LU:
 670                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
 671  reset:
 672                         tmf_resp = sas_recover_lu(task->dev, cmd);
 673                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 674                                 SAS_DPRINTK("dev %016llx LU %x is "
 675                                             "recovered\n",
 676                                             SAS_ADDR(task->dev),
 677                                             cmd->device->lun);
 678                                 sas_eh_defer_cmd(cmd);
 679                                 sas_scsi_clear_queue_lu(work_q, cmd);
 680                                 goto Again;
 681                         }
 682                         /* fallthrough */
 683                 case TASK_IS_NOT_AT_LU:
 684                 case TASK_ABORT_FAILED:
 685                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
 686                                     task);
 687                         tmf_resp = sas_recover_I_T(task->dev);
 688                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
 689                             tmf_resp == -ENODEV) {
 690                                 struct domain_device *dev = task->dev;
 691                                 SAS_DPRINTK("I_T %016llx recovered\n",
 692                                             SAS_ADDR(task->dev->sas_addr));
 693                                 sas_eh_finish_cmd(cmd);
 694                                 sas_scsi_clear_queue_I_T(work_q, dev);
 695                                 goto Again;
 696                         }
 697                         /* Hammer time :-) */
 698                         try_to_reset_cmd_device(cmd);
 699                         if (i->dft->lldd_clear_nexus_port) {
 700                                 struct asd_sas_port *port = task->dev->port;
 701                                 SAS_DPRINTK("clearing nexus for port:%d\n",
 702                                             port->id);
 703                                 res = i->dft->lldd_clear_nexus_port(port);
 704                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 705                                         SAS_DPRINTK("clear nexus port:%d "
 706                                                     "succeeded\n", port->id);
 707                                         sas_eh_finish_cmd(cmd);
 708                                         sas_scsi_clear_queue_port(work_q,
 709                                                                   port);
 710                                         goto Again;
 711                                 }
 712                         }
 713                         if (i->dft->lldd_clear_nexus_ha) {
 714                                 SAS_DPRINTK("clear nexus ha\n");
 715                                 res = i->dft->lldd_clear_nexus_ha(ha);
 716                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 717                                         SAS_DPRINTK("clear nexus ha "
 718                                                     "succeeded\n");
 719                                         sas_eh_finish_cmd(cmd);
 720                                         goto clear_q;
 721                                 }
 722                         }
 723                         /* If we are here -- this means that no amount
 724                          * of effort could recover from errors.  Quite
 725                          * possibly the HA just disappeared.
 726                          */
 727                         SAS_DPRINTK("error from  device %llx, LUN %x "
 728                                     "couldn't be recovered in any way\n",
 729                                     SAS_ADDR(task->dev->sas_addr),
 730                                     cmd->device->lun);
 731
 732                         sas_eh_finish_cmd(cmd);
 733                         goto clear_q;
 734                 }
 735         }
 736  out:
 737         list_splice_tail(&done, work_q);
 738         list_splice_tail_init(&ha->eh_ata_q, work_q);
 739         return;
 740
 741  clear_q:
 742         SAS_DPRINTK("--- Exit %s -- clear_q\n", __func__);
 743         list_for_each_entry_safe(cmd, n, work_q, eh_entry)
 744                 sas_eh_finish_cmd(cmd);
 745         goto out;
 746 }
 747
 748 static void sas_eh_handle_resets(struct Scsi_Host *shost)
 749 {
 750         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 751         struct sas_internal *i = to_sas_internal(shost->transportt);
 752
 753         /* handle directed resets to sas devices */
 754         spin_lock_irq(&ha->lock);
 755         while (!list_empty(&ha->eh_dev_q)) {
 756                 struct domain_device *dev;
 757                 struct ssp_device *ssp;
 758
 759                 ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
 760                 list_del_init(&ssp->eh_list_node);
 761                 dev = container_of(ssp, typeof(*dev), ssp_dev);
 762                 kref_get(&dev->kref);
 763                 WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
 764
 765                 spin_unlock_irq(&ha->lock);
 766
 767                 if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
 768                         i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
 769
 770                 if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
 771                         i->dft->lldd_I_T_nexus_reset(dev);
 772
 773                 sas_put_device(dev);
 774                 spin_lock_irq(&ha->lock);
 775                 clear_bit(SAS_DEV_EH_PENDING, &dev->state);
 776                 ha->eh_active--;
 777         }
 778         spin_unlock_irq(&ha->lock);
 779 }
 780
 781
 782 void sas_scsi_recover_host(struct Scsi_Host *shost)
 783 {
 784         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 785         LIST_HEAD(eh_work_q);
 786         int tries = 0;
 787         bool retry;
 788
 789 retry:
 790         tries++;
 791         retry = true;
 792         spin_lock_irq(shost->host_lock);
 793         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
 794         spin_unlock_irq(shost->host_lock);
 795
 796         SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
 797                     __func__, shost->host_busy, shost->host_failed);
 798         /*
 799          * Deal with commands that still have SAS tasks (i.e. they didn't
 800          * complete via the normal sas_task completion mechanism),
 801          * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
 802          */
 803         set_bit(SAS_HA_FROZEN, &ha->state);
 804         sas_eh_handle_sas_errors(shost, &eh_work_q);
 805         clear_bit(SAS_HA_FROZEN, &ha->state);
 806         if (list_empty(&eh_work_q))
 807                 goto out;
 808
 809         /*
 810          * Now deal with SCSI commands that completed ok but have a an error
 811          * code (and hopefully sense data) attached.  This is roughly what
 812          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
 813          * command we see here has no sas_task and is thus unknown to the HA.
 814          */
 815         sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
 816         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
 817                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
 818
 819 out:
 820         if (ha->lldd_max_execute_num > 1)
 821                 wake_up_process(ha->core.queue_thread);
 822
 823         sas_eh_handle_resets(shost);
 824
 825         /* now link into libata eh --- if we have any ata devices */
 826         sas_ata_strategy_handler(shost);
 827
 828         scsi_eh_flush_done_q(&ha->eh_done_q);
 829
 830         /* check if any new eh work was scheduled during the last run */
 831         spin_lock_irq(&ha->lock);
 832         if (ha->eh_active == 0) {
 833                 shost->host_eh_scheduled = 0;
 834                 retry = false;
 835         }
 836         spin_unlock_irq(&ha->lock);
 837
 838         if (retry)
 839                 goto retry;
 840
 841         SAS_DPRINTK("--- Exit %s: busy: %d failed: %d tries: %d\n",
 842                     __func__, shost->host_busy, shost->host_failed, tries);
 843 }
 844
 845 enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
 846 {
 847         scmd_printk(KERN_DEBUG, cmd, "command %p timed out\n", cmd);
 848
 849         return BLK_EH_NOT_HANDLED;
 850 }
 851
 852 int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
 853 {
 854         struct domain_device *dev = sdev_to_domain_dev(sdev);
 855
 856         if (dev_is_sata(dev))
 857                 return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
 858
 859         return -EINVAL;
 860 }
 861
 862 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
 863 {
 864         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
 865         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 866         struct domain_device *found_dev = NULL;
 867         int i;
 868         unsigned long flags;
 869
 870         spin_lock_irqsave(&ha->phy_port_lock, flags);
 871         for (i = 0; i < ha->num_phys; i++) {
 872                 struct asd_sas_port *port = ha->sas_port[i];
 873                 struct domain_device *dev;
 874
 875                 spin_lock(&port->dev_list_lock);
 876                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
 877                         if (rphy == dev->rphy) {
 878                                 found_dev = dev;
 879                                 spin_unlock(&port->dev_list_lock);
 880                                 goto found;
 881                         }
 882                 }
 883                 spin_unlock(&port->dev_list_lock);
 884         }
 885  found:
 886         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 887
 888         return found_dev;
 889 }
 890
 891 int sas_target_alloc(struct scsi_target *starget)
 892 {
 893         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
 894         struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
 895
 896         if (!found_dev)
 897                 return -ENODEV;
 898
 899         kref_get(&found_dev->kref);
 900         starget->hostdata = found_dev;
 901         return 0;
 902 }
 903
 904 #define SAS_DEF_QD 256
 905
 906 int sas_slave_configure(struct scsi_device *scsi_dev)
 907 {
 908         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 909         struct sas_ha_struct *sas_ha;
 910
 911         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
 912
 913         if (dev_is_sata(dev)) {
 914                 ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
 915                 return 0;
 916         }
 917
 918         sas_ha = dev->port->ha;
 919
 920         sas_read_port_mode_page(scsi_dev);
 921
 922         if (scsi_dev->tagged_supported) {
 923                 scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
 924                 scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
 925         } else {
 926                 SAS_DPRINTK("device %llx, LUN %x doesn't support "
 927                             "TCQ\n", SAS_ADDR(dev->sas_addr),
 928                             scsi_dev->lun);
 929                 scsi_dev->tagged_supported = 0;
 930                 scsi_set_tag_type(scsi_dev, 0);
 931                 scsi_deactivate_tcq(scsi_dev, 1);
 932         }
 933
 934         scsi_dev->allow_restart = 1;
 935
 936         return 0;
 937 }
 938
 939 int sas_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
 940 {
 941         struct domain_device *dev = sdev_to_domain_dev(sdev);
 942
 943         if (dev_is_sata(dev))
 944                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth,
 945                                                 reason);
 946
 947         switch (reason) {
 948         case SCSI_QDEPTH_DEFAULT:
 949         case SCSI_QDEPTH_RAMP_UP:
 950                 if (!sdev->tagged_supported)
 951                         depth = 1;
 952                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 953                 break;
 954         case SCSI_QDEPTH_QFULL:
 955                 scsi_track_queue_full(sdev, depth);
 956                 break;
 957         default:
 958                 return -EOPNOTSUPP;
 959         }
 960
 961         return depth;
 962 }
 963
 964 int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
 965 {
 966         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 967
 968         if (dev_is_sata(dev))
 969                 return -EINVAL;
 970
 971         if (!scsi_dev->tagged_supported)
 972                 return 0;
 973
 974         scsi_deactivate_tcq(scsi_dev, 1);
 975
 976         scsi_set_tag_type(scsi_dev, qt);
 977         scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
 978
 979         return qt;
 980 }
 981
 982 int sas_bios_param(struct scsi_device *scsi_dev,
 983                           struct block_device *bdev,
 984                           sector_t capacity, int *hsc)
 985 {
 986         hsc[0] = 255;
 987         hsc[1] = 63;
 988         sector_div(capacity, 255*63);
 989         hsc[2] = capacity;
 990
 991         return 0;
 992 }
 993
 994 /* ---------- Task Collector Thread implementation ---------- */
 995
 996 static void sas_queue(struct sas_ha_struct *sas_ha)
 997 {
 998         struct scsi_core *core = &sas_ha->core;
 999         unsigned long flags;
1000         LIST_HEAD(q);
1001         int can_queue;
1002         int res;
1003         struct sas_internal *i = to_sas_internal(core->shost->transportt);
1004
1005         mutex_lock(&core->task_queue_flush);
1006         spin_lock_irqsave(&core->task_queue_lock, flags);
1007         while (!kthread_should_stop() &&
1008                !list_empty(&core->task_queue) &&
1009                !test_bit(SAS_HA_FROZEN, &sas_ha->state)) {
1010
1011                 can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
1012                 if (can_queue >= 0) {
1013                         can_queue = core->task_queue_size;
1014                         list_splice_init(&core->task_queue, &q);
1015                 } else {
1016                         struct list_head *a, *n;
1017
1018                         can_queue = sas_ha->lldd_queue_size;
1019                         list_for_each_safe(a, n, &core->task_queue) {
1020                                 list_move_tail(a, &q);
1021                                 if (--can_queue == 0)
1022                                         break;
1023                         }
1024                         can_queue = sas_ha->lldd_queue_size;
1025                 }
1026                 core->task_queue_size -= can_queue;
1027                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
1028                 {
1029                         struct sas_task *task = list_entry(q.next,
1030                                                            struct sas_task,
1031                                                            list);
1032                         list_del_init(&q);
1033                         res = i->dft->lldd_execute_task(task, can_queue,
1034                                                         GFP_KERNEL);
1035                         if (unlikely(res))
1036                                 __list_add(&q, task->list.prev, &task->list);
1037                 }
1038                 spin_lock_irqsave(&core->task_queue_lock, flags);
1039                 if (res) {
1040                         list_splice_init(&q, &core->task_queue); /*at head*/
1041                         core->task_queue_size += can_queue;
1042                 }
1043         }
1044         spin_unlock_irqrestore(&core->task_queue_lock, flags);
1045         mutex_unlock(&core->task_queue_flush);
1046 }
1047
1048 /**
1049  * sas_queue_thread -- The Task Collector thread
1050  * @_sas_ha: pointer to struct sas_ha
1051  */
1052 static int sas_queue_thread(void *_sas_ha)
1053 {
1054         struct sas_ha_struct *sas_ha = _sas_ha;
1055
1056         while (1) {
1057                 set_current_state(TASK_INTERRUPTIBLE);
1058                 schedule();
1059                 sas_queue(sas_ha);
1060                 if (kthread_should_stop())
1061                         break;
1062         }
1063
1064         return 0;
1065 }
1066
1067 int sas_init_queue(struct sas_ha_struct *sas_ha)
1068 {
1069         struct scsi_core *core = &sas_ha->core;
1070
1071         spin_lock_init(&core->task_queue_lock);
1072         mutex_init(&core->task_queue_flush);
1073         core->task_queue_size = 0;
1074         INIT_LIST_HEAD(&core->task_queue);
1075
1076         core->queue_thread = kthread_run(sas_queue_thread, sas_ha,
1077                                          "sas_queue_%d", core->shost->host_no);
1078         if (IS_ERR(core->queue_thread))
1079                 return PTR_ERR(core->queue_thread);
1080         return 0;
1081 }
1082
1083 void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
1084 {
1085         unsigned long flags;
1086         struct scsi_core *core = &sas_ha->core;
1087         struct sas_task *task, *n;
1088
1089         kthread_stop(core->queue_thread);
1090
1091         if (!list_empty(&core->task_queue))
1092                 SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
1093                             SAS_ADDR(sas_ha->sas_addr));
1094
1095         spin_lock_irqsave(&core->task_queue_lock, flags);
1096         list_for_each_entry_safe(task, n, &core->task_queue, list) {
1097                 struct scsi_cmnd *cmd = task->uldd_task;
1098
1099                 list_del_init(&task->list);
1100
1101                 ASSIGN_SAS_TASK(cmd, NULL);
1102                 sas_free_task(task);
1103                 cmd->result = DID_ABORT << 16;
1104                 cmd->scsi_done(cmd);
1105         }
1106         spin_unlock_irqrestore(&core->task_queue_lock, flags);
1107 }
1108
1109 /*
1110  * Tell an upper layer that it needs to initiate an abort for a given task.
1111  * This should only ever be called by an LLDD.
1112  */
1113 void sas_task_abort(struct sas_task *task)
1114 {
1115         struct scsi_cmnd *sc = task->uldd_task;
1116
1117         /* Escape for libsas internal commands */
1118         if (!sc) {
1119                 if (!del_timer(&task->timer))
1120                         return;
1121                 task->timer.function(task->timer.data);
1122                 return;
1123         }
1124
1125         if (dev_is_sata(task->dev)) {
1126                 sas_ata_task_abort(task);
1127         } else {
1128                 struct request_queue *q = sc->device->request_queue;
1129                 unsigned long flags;
1130
1131                 spin_lock_irqsave(q->queue_lock, flags);
1132                 blk_abort_request(sc->request);
1133                 spin_unlock_irqrestore(q->queue_lock, flags);
1134         }
1135 }
1136
1137 void sas_target_destroy(struct scsi_target *starget)
1138 {
1139         struct domain_device *found_dev = starget->hostdata;
1140
1141         if (!found_dev)
1142                 return;
1143
1144         starget->hostdata = NULL;
1145         sas_put_device(found_dev);
1146 }
1147
1148 static void sas_parse_addr(u8 *sas_addr, const char *p)
1149 {
1150         int i;
1151         for (i = 0; i < SAS_ADDR_SIZE; i++) {
1152                 u8 h, l;
1153                 if (!*p)
1154                         break;
1155                 h = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
1156                 p++;
1157                 l = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
1158                 p++;
1159                 sas_addr[i] = (h<<4) | l;
1160         }
1161 }
1162
1163 #define SAS_STRING_ADDR_SIZE    16
1164
1165 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
1166 {
1167         int res;
1168         const struct firmware *fw;
1169
1170         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
1171         if (res)
1172                 return res;
1173
1174         if (fw->size < SAS_STRING_ADDR_SIZE) {
1175                 res = -ENODEV;
1176                 goto out;
1177         }
1178
1179         sas_parse_addr(addr, fw->data);
1180
1181 out:
1182         release_firmware(fw);
1183         return res;
1184 }
1185 EXPORT_SYMBOL_GPL(sas_request_addr);
1186
1187 EXPORT_SYMBOL_GPL(sas_queuecommand);
1188 EXPORT_SYMBOL_GPL(sas_target_alloc);
1189 EXPORT_SYMBOL_GPL(sas_slave_configure);
1190 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
1191 EXPORT_SYMBOL_GPL(sas_change_queue_type);
1192 EXPORT_SYMBOL_GPL(sas_bios_param);
1193 EXPORT_SYMBOL_GPL(sas_task_abort);
1194 EXPORT_SYMBOL_GPL(sas_phy_reset);
1195 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
1196 EXPORT_SYMBOL_GPL(sas_eh_bus_reset_handler);
1197 EXPORT_SYMBOL_GPL(sas_target_destroy);
1198 EXPORT_SYMBOL_GPL(sas_ioctl);