kernel/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         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                 SAS_DPRINTK("task done but aborted\n");
 135                 return;
 136         }
 137
 138         if (unlikely(!sc)) {
 139                 SAS_DPRINTK("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         SAS_DPRINTK("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 sas_task *task = TO_SAS_TASK(cmd);
 226
 227         /* At this point, we only get called following an actual abort
 228          * of the task, so we should be guaranteed not to be racing with
 229          * any completions from the LLD.  Task is freed after this.
 230          */
 231         sas_end_task(cmd, task);
 232
 233         /* now finish the command and move it on to the error
 234          * handler done list, this also takes it off the
 235          * error handler pending list.
 236          */
 237         scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
 238 }
 239
 240 static void sas_eh_defer_cmd(struct scsi_cmnd *cmd)
 241 {
 242         struct domain_device *dev = cmd_to_domain_dev(cmd);
 243         struct sas_ha_struct *ha = dev->port->ha;
 244         struct sas_task *task = TO_SAS_TASK(cmd);
 245
 246         if (!dev_is_sata(dev)) {
 247                 sas_eh_finish_cmd(cmd);
 248                 return;
 249         }
 250
 251         /* report the timeout to libata */
 252         sas_end_task(cmd, task);
 253         list_move_tail(&cmd->eh_entry, &ha->eh_ata_q);
 254 }
 255
 256 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 257 {
 258         struct scsi_cmnd *cmd, *n;
 259
 260         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 261                 if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
 262                     cmd->device->lun == my_cmd->device->lun)
 263                         sas_eh_defer_cmd(cmd);
 264         }
 265 }
 266
 267 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 268                                      struct domain_device *dev)
 269 {
 270         struct scsi_cmnd *cmd, *n;
 271
 272         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 273                 struct domain_device *x = cmd_to_domain_dev(cmd);
 274
 275                 if (x == dev)
 276                         sas_eh_finish_cmd(cmd);
 277         }
 278 }
 279
 280 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 281                                       struct asd_sas_port *port)
 282 {
 283         struct scsi_cmnd *cmd, *n;
 284
 285         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 286                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 287                 struct asd_sas_port *x = dev->port;
 288
 289                 if (x == port)
 290                         sas_eh_finish_cmd(cmd);
 291         }
 292 }
 293
 294 enum task_disposition {
 295         TASK_IS_DONE,
 296         TASK_IS_ABORTED,
 297         TASK_IS_AT_LU,
 298         TASK_IS_NOT_AT_LU,
 299         TASK_ABORT_FAILED,
 300 };
 301
 302 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 303 {
 304         unsigned long flags;
 305         int i, res;
 306         struct sas_internal *si =
 307                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 308
 309         for (i = 0; i < 5; i++) {
 310                 SAS_DPRINTK("%s: aborting task 0x%p\n", __func__, task);
 311                 res = si->dft->lldd_abort_task(task);
 312
 313                 spin_lock_irqsave(&task->task_state_lock, flags);
 314                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 315                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 316                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
 317                                     task);
 318                         return TASK_IS_DONE;
 319                 }
 320                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 321
 322                 if (res == TMF_RESP_FUNC_COMPLETE) {
 323                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 324                                     __func__, task);
 325                         return TASK_IS_ABORTED;
 326                 } else if (si->dft->lldd_query_task) {
 327                         SAS_DPRINTK("%s: querying task 0x%p\n",
 328                                     __func__, task);
 329                         res = si->dft->lldd_query_task(task);
 330                         switch (res) {
 331                         case TMF_RESP_FUNC_SUCC:
 332                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
 333                                             __func__, task);
 334                                 return TASK_IS_AT_LU;
 335                         case TMF_RESP_FUNC_COMPLETE:
 336                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
 337                                             __func__, task);
 338                                 return TASK_IS_NOT_AT_LU;
 339                         case TMF_RESP_FUNC_FAILED:
 340                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
 341                                                 __func__, task);
 342                                 return TASK_ABORT_FAILED;
 343                         }
 344
 345                 }
 346         }
 347         return res;
 348 }
 349
 350 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 351 {
 352         int res = TMF_RESP_FUNC_FAILED;
 353         struct scsi_lun lun;
 354         struct sas_internal *i =
 355                 to_sas_internal(dev->port->ha->core.shost->transportt);
 356
 357         int_to_scsilun(cmd->device->lun, &lun);
 358
 359         SAS_DPRINTK("eh: device %llx LUN %llx has the task\n",
 360                     SAS_ADDR(dev->sas_addr),
 361                     cmd->device->lun);
 362
 363         if (i->dft->lldd_abort_task_set)
 364                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 365
 366         if (res == TMF_RESP_FUNC_FAILED) {
 367                 if (i->dft->lldd_clear_task_set)
 368                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 369         }
 370
 371         if (res == TMF_RESP_FUNC_FAILED) {
 372                 if (i->dft->lldd_lu_reset)
 373                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 374         }
 375
 376         return res;
 377 }
 378
 379 static int sas_recover_I_T(struct domain_device *dev)
 380 {
 381         int res = TMF_RESP_FUNC_FAILED;
 382         struct sas_internal *i =
 383                 to_sas_internal(dev->port->ha->core.shost->transportt);
 384
 385         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
 386                     SAS_ADDR(dev->sas_addr));
 387
 388         if (i->dft->lldd_I_T_nexus_reset)
 389                 res = i->dft->lldd_I_T_nexus_reset(dev);
 390
 391         return res;
 392 }
 393
 394 /* take a reference on the last known good phy for this device */
 395 struct sas_phy *sas_get_local_phy(struct domain_device *dev)
 396 {
 397         struct sas_ha_struct *ha = dev->port->ha;
 398         struct sas_phy *phy;
 399         unsigned long flags;
 400
 401         /* a published domain device always has a valid phy, it may be
 402          * stale, but it is never NULL
 403          */
 404         BUG_ON(!dev->phy);
 405
 406         spin_lock_irqsave(&ha->phy_port_lock, flags);
 407         phy = dev->phy;
 408         get_device(&phy->dev);
 409         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 410
 411         return phy;
 412 }
 413 EXPORT_SYMBOL_GPL(sas_get_local_phy);
 414
 415 static void sas_wait_eh(struct domain_device *dev)
 416 {
 417         struct sas_ha_struct *ha = dev->port->ha;
 418         DEFINE_WAIT(wait);
 419
 420         if (dev_is_sata(dev)) {
 421                 ata_port_wait_eh(dev->sata_dev.ap);
 422                 return;
 423         }
 424  retry:
 425         spin_lock_irq(&ha->lock);
 426
 427         while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
 428                 prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 429                 spin_unlock_irq(&ha->lock);
 430                 schedule();
 431                 spin_lock_irq(&ha->lock);
 432         }
 433         finish_wait(&ha->eh_wait_q, &wait);
 434
 435         spin_unlock_irq(&ha->lock);
 436
 437         /* make sure SCSI EH is complete */
 438         if (scsi_host_in_recovery(ha->core.shost)) {
 439                 msleep(10);
 440                 goto retry;
 441         }
 442 }
 443 EXPORT_SYMBOL(sas_wait_eh);
 444
 445 static int sas_queue_reset(struct domain_device *dev, int reset_type,
 446                            u64 lun, int wait)
 447 {
 448         struct sas_ha_struct *ha = dev->port->ha;
 449         int scheduled = 0, tries = 100;
 450
 451         /* ata: promote lun reset to bus reset */
 452         if (dev_is_sata(dev)) {
 453                 sas_ata_schedule_reset(dev);
 454                 if (wait)
 455                         sas_ata_wait_eh(dev);
 456                 return SUCCESS;
 457         }
 458
 459         while (!scheduled && tries--) {
 460                 spin_lock_irq(&ha->lock);
 461                 if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
 462                     !test_bit(reset_type, &dev->state)) {
 463                         scheduled = 1;
 464                         ha->eh_active++;
 465                         list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
 466                         set_bit(SAS_DEV_EH_PENDING, &dev->state);
 467                         set_bit(reset_type, &dev->state);
 468                         int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
 469                         scsi_schedule_eh(ha->core.shost);
 470                 }
 471                 spin_unlock_irq(&ha->lock);
 472
 473                 if (wait)
 474                         sas_wait_eh(dev);
 475
 476                 if (scheduled)
 477                         return SUCCESS;
 478         }
 479
 480         SAS_DPRINTK("%s reset of %s failed\n",
 481                     reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
 482                     dev_name(&dev->rphy->dev));
 483
 484         return FAILED;
 485 }
 486
 487 int sas_eh_abort_handler(struct scsi_cmnd *cmd)
 488 {
 489         int res;
 490         struct sas_task *task = TO_SAS_TASK(cmd);
 491         struct Scsi_Host *host = cmd->device->host;
 492         struct sas_internal *i = to_sas_internal(host->transportt);
 493
 494         if (current != host->ehandler)
 495                 return FAILED;
 496
 497         if (!i->dft->lldd_abort_task)
 498                 return FAILED;
 499
 500         res = i->dft->lldd_abort_task(task);
 501         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 502                 return SUCCESS;
 503
 504         return FAILED;
 505 }
 506 EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
 507
 508 /* Attempt to send a LUN reset message to a device */
 509 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 510 {
 511         int res;
 512         struct scsi_lun lun;
 513         struct Scsi_Host *host = cmd->device->host;
 514         struct domain_device *dev = cmd_to_domain_dev(cmd);
 515         struct sas_internal *i = to_sas_internal(host->transportt);
 516
 517         if (current != host->ehandler)
 518                 return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
 519
 520         int_to_scsilun(cmd->device->lun, &lun);
 521
 522         if (!i->dft->lldd_lu_reset)
 523                 return FAILED;
 524
 525         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 526         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 527                 return SUCCESS;
 528
 529         return FAILED;
 530 }
 531
 532 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
 533 {
 534         int res;
 535         struct Scsi_Host *host = cmd->device->host;
 536         struct domain_device *dev = cmd_to_domain_dev(cmd);
 537         struct sas_internal *i = to_sas_internal(host->transportt);
 538
 539         if (current != host->ehandler)
 540                 return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
 541
 542         if (!i->dft->lldd_I_T_nexus_reset)
 543                 return FAILED;
 544
 545         res = i->dft->lldd_I_T_nexus_reset(dev);
 546         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
 547             res == -ENODEV)
 548                 return SUCCESS;
 549
 550         return FAILED;
 551 }
 552
 553 /* Try to reset a device */
 554 static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
 555 {
 556         int res;
 557         struct Scsi_Host *shost = cmd->device->host;
 558
 559         if (!shost->hostt->eh_device_reset_handler)
 560                 goto try_bus_reset;
 561
 562         res = shost->hostt->eh_device_reset_handler(cmd);
 563         if (res == SUCCESS)
 564                 return res;
 565
 566 try_bus_reset:
 567         if (shost->hostt->eh_bus_reset_handler)
 568                 return shost->hostt->eh_bus_reset_handler(cmd);
 569
 570         return FAILED;
 571 }
 572
 573 static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
 574 {
 575         struct scsi_cmnd *cmd, *n;
 576         enum task_disposition res = TASK_IS_DONE;
 577         int tmf_resp, need_reset;
 578         struct sas_internal *i = to_sas_internal(shost->transportt);
 579         unsigned long flags;
 580         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 581         LIST_HEAD(done);
 582
 583         /* clean out any commands that won the completion vs eh race */
 584         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 585                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 586                 struct sas_task *task;
 587
 588                 spin_lock_irqsave(&dev->done_lock, flags);
 589                 /* by this point the lldd has either observed
 590                  * SAS_HA_FROZEN and is leaving the task alone, or has
 591                  * won the race with eh and decided to complete it
 592                  */
 593                 task = TO_SAS_TASK(cmd);
 594                 spin_unlock_irqrestore(&dev->done_lock, flags);
 595
 596                 if (!task)
 597                         list_move_tail(&cmd->eh_entry, &done);
 598         }
 599
 600  Again:
 601         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 602                 struct sas_task *task = TO_SAS_TASK(cmd);
 603
 604                 list_del_init(&cmd->eh_entry);
 605
 606                 spin_lock_irqsave(&task->task_state_lock, flags);
 607                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 608                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 609
 610                 if (need_reset) {
 611                         SAS_DPRINTK("%s: task 0x%p requests reset\n",
 612                                     __func__, task);
 613                         goto reset;
 614                 }
 615
 616                 SAS_DPRINTK("trying to find task 0x%p\n", task);
 617                 res = sas_scsi_find_task(task);
 618
 619                 cmd->eh_eflags = 0;
 620
 621                 switch (res) {
 622                 case TASK_IS_DONE:
 623                         SAS_DPRINTK("%s: task 0x%p is done\n", __func__,
 624                                     task);
 625                         sas_eh_defer_cmd(cmd);
 626                         continue;
 627                 case TASK_IS_ABORTED:
 628                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 629                                     __func__, task);
 630                         sas_eh_defer_cmd(cmd);
 631                         continue;
 632                 case TASK_IS_AT_LU:
 633                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
 634  reset:
 635                         tmf_resp = sas_recover_lu(task->dev, cmd);
 636                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 637                                 SAS_DPRINTK("dev %016llx LU %llx is "
 638                                             "recovered\n",
 639                                             SAS_ADDR(task->dev),
 640                                             cmd->device->lun);
 641                                 sas_eh_defer_cmd(cmd);
 642                                 sas_scsi_clear_queue_lu(work_q, cmd);
 643                                 goto Again;
 644                         }
 645                         /* fallthrough */
 646                 case TASK_IS_NOT_AT_LU:
 647                 case TASK_ABORT_FAILED:
 648                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
 649                                     task);
 650                         tmf_resp = sas_recover_I_T(task->dev);
 651                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
 652                             tmf_resp == -ENODEV) {
 653                                 struct domain_device *dev = task->dev;
 654                                 SAS_DPRINTK("I_T %016llx recovered\n",
 655                                             SAS_ADDR(task->dev->sas_addr));
 656                                 sas_eh_finish_cmd(cmd);
 657                                 sas_scsi_clear_queue_I_T(work_q, dev);
 658                                 goto Again;
 659                         }
 660                         /* Hammer time :-) */
 661                         try_to_reset_cmd_device(cmd);
 662                         if (i->dft->lldd_clear_nexus_port) {
 663                                 struct asd_sas_port *port = task->dev->port;
 664                                 SAS_DPRINTK("clearing nexus for port:%d\n",
 665                                             port->id);
 666                                 res = i->dft->lldd_clear_nexus_port(port);
 667                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 668                                         SAS_DPRINTK("clear nexus port:%d "
 669                                                     "succeeded\n", port->id);
 670                                         sas_eh_finish_cmd(cmd);
 671                                         sas_scsi_clear_queue_port(work_q,
 672                                                                   port);
 673                                         goto Again;
 674                                 }
 675                         }
 676                         if (i->dft->lldd_clear_nexus_ha) {
 677                                 SAS_DPRINTK("clear nexus ha\n");
 678                                 res = i->dft->lldd_clear_nexus_ha(ha);
 679                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 680                                         SAS_DPRINTK("clear nexus ha "
 681                                                     "succeeded\n");
 682                                         sas_eh_finish_cmd(cmd);
 683                                         goto clear_q;
 684                                 }
 685                         }
 686                         /* If we are here -- this means that no amount
 687                          * of effort could recover from errors.  Quite
 688                          * possibly the HA just disappeared.
 689                          */
 690                         SAS_DPRINTK("error from  device %llx, LUN %llx "
 691                                     "couldn't be recovered in any way\n",
 692                                     SAS_ADDR(task->dev->sas_addr),
 693                                     cmd->device->lun);
 694
 695                         sas_eh_finish_cmd(cmd);
 696                         goto clear_q;
 697                 }
 698         }
 699  out:
 700         list_splice_tail(&done, work_q);
 701         list_splice_tail_init(&ha->eh_ata_q, work_q);
 702         return;
 703
 704  clear_q:
 705         SAS_DPRINTK("--- Exit %s -- clear_q\n", __func__);
 706         list_for_each_entry_safe(cmd, n, work_q, eh_entry)
 707                 sas_eh_finish_cmd(cmd);
 708         goto out;
 709 }
 710
 711 static void sas_eh_handle_resets(struct Scsi_Host *shost)
 712 {
 713         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 714         struct sas_internal *i = to_sas_internal(shost->transportt);
 715
 716         /* handle directed resets to sas devices */
 717         spin_lock_irq(&ha->lock);
 718         while (!list_empty(&ha->eh_dev_q)) {
 719                 struct domain_device *dev;
 720                 struct ssp_device *ssp;
 721
 722                 ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
 723                 list_del_init(&ssp->eh_list_node);
 724                 dev = container_of(ssp, typeof(*dev), ssp_dev);
 725                 kref_get(&dev->kref);
 726                 WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
 727
 728                 spin_unlock_irq(&ha->lock);
 729
 730                 if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
 731                         i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
 732
 733                 if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
 734                         i->dft->lldd_I_T_nexus_reset(dev);
 735
 736                 sas_put_device(dev);
 737                 spin_lock_irq(&ha->lock);
 738                 clear_bit(SAS_DEV_EH_PENDING, &dev->state);
 739                 ha->eh_active--;
 740         }
 741         spin_unlock_irq(&ha->lock);
 742 }
 743
 744
 745 void sas_scsi_recover_host(struct Scsi_Host *shost)
 746 {
 747         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 748         LIST_HEAD(eh_work_q);
 749         int tries = 0;
 750         bool retry;
 751
 752 retry:
 753         tries++;
 754         retry = true;
 755         spin_lock_irq(shost->host_lock);
 756         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
 757         spin_unlock_irq(shost->host_lock);
 758
 759         SAS_DPRINTK("Enter %s busy: %d failed: %d\n",
 760                     __func__, atomic_read(&shost->host_busy), shost->host_failed);
 761         /*
 762          * Deal with commands that still have SAS tasks (i.e. they didn't
 763          * complete via the normal sas_task completion mechanism),
 764          * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
 765          */
 766         set_bit(SAS_HA_FROZEN, &ha->state);
 767         sas_eh_handle_sas_errors(shost, &eh_work_q);
 768         clear_bit(SAS_HA_FROZEN, &ha->state);
 769         if (list_empty(&eh_work_q))
 770                 goto out;
 771
 772         /*
 773          * Now deal with SCSI commands that completed ok but have a an error
 774          * code (and hopefully sense data) attached.  This is roughly what
 775          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
 776          * command we see here has no sas_task and is thus unknown to the HA.
 777          */
 778         sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
 779         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
 780                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
 781
 782 out:
 783         sas_eh_handle_resets(shost);
 784
 785         /* now link into libata eh --- if we have any ata devices */
 786         sas_ata_strategy_handler(shost);
 787
 788         scsi_eh_flush_done_q(&ha->eh_done_q);
 789
 790         /* check if any new eh work was scheduled during the last run */
 791         spin_lock_irq(&ha->lock);
 792         if (ha->eh_active == 0) {
 793                 shost->host_eh_scheduled = 0;
 794                 retry = false;
 795         }
 796         spin_unlock_irq(&ha->lock);
 797
 798         if (retry)
 799                 goto retry;
 800
 801         SAS_DPRINTK("--- Exit %s: busy: %d failed: %d tries: %d\n",
 802                     __func__, atomic_read(&shost->host_busy),
 803                     shost->host_failed, tries);
 804 }
 805
 806 enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
 807 {
 808         scmd_dbg(cmd, "command %p timed out\n", cmd);
 809
 810         return BLK_EH_NOT_HANDLED;
 811 }
 812
 813 int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
 814 {
 815         struct domain_device *dev = sdev_to_domain_dev(sdev);
 816
 817         if (dev_is_sata(dev))
 818                 return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
 819
 820         return -EINVAL;
 821 }
 822
 823 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
 824 {
 825         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
 826         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 827         struct domain_device *found_dev = NULL;
 828         int i;
 829         unsigned long flags;
 830
 831         spin_lock_irqsave(&ha->phy_port_lock, flags);
 832         for (i = 0; i < ha->num_phys; i++) {
 833                 struct asd_sas_port *port = ha->sas_port[i];
 834                 struct domain_device *dev;
 835
 836                 spin_lock(&port->dev_list_lock);
 837                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
 838                         if (rphy == dev->rphy) {
 839                                 found_dev = dev;
 840                                 spin_unlock(&port->dev_list_lock);
 841                                 goto found;
 842                         }
 843                 }
 844                 spin_unlock(&port->dev_list_lock);
 845         }
 846  found:
 847         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 848
 849         return found_dev;
 850 }
 851
 852 int sas_target_alloc(struct scsi_target *starget)
 853 {
 854         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
 855         struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
 856
 857         if (!found_dev)
 858                 return -ENODEV;
 859
 860         kref_get(&found_dev->kref);
 861         starget->hostdata = found_dev;
 862         return 0;
 863 }
 864
 865 #define SAS_DEF_QD 256
 866
 867 int sas_slave_configure(struct scsi_device *scsi_dev)
 868 {
 869         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 870         struct sas_ha_struct *sas_ha;
 871
 872         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
 873
 874         if (dev_is_sata(dev)) {
 875                 ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
 876                 return 0;
 877         }
 878
 879         sas_ha = dev->port->ha;
 880
 881         sas_read_port_mode_page(scsi_dev);
 882
 883         if (scsi_dev->tagged_supported) {
 884                 scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
 885         } else {
 886                 SAS_DPRINTK("device %llx, LUN %llx doesn't support "
 887                             "TCQ\n", SAS_ADDR(dev->sas_addr),
 888                             scsi_dev->lun);
 889                 scsi_change_queue_depth(scsi_dev, 1);
 890         }
 891
 892         scsi_dev->allow_restart = 1;
 893
 894         return 0;
 895 }
 896
 897 int sas_change_queue_depth(struct scsi_device *sdev, int depth)
 898 {
 899         struct domain_device *dev = sdev_to_domain_dev(sdev);
 900
 901         if (dev_is_sata(dev))
 902                 return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
 903
 904         if (!sdev->tagged_supported)
 905                 depth = 1;
 906         return scsi_change_queue_depth(sdev, depth);
 907 }
 908
 909 int sas_bios_param(struct scsi_device *scsi_dev,
 910                           struct block_device *bdev,
 911                           sector_t capacity, int *hsc)
 912 {
 913         hsc[0] = 255;
 914         hsc[1] = 63;
 915         sector_div(capacity, 255*63);
 916         hsc[2] = capacity;
 917
 918         return 0;
 919 }
 920
 921 /*
 922  * Tell an upper layer that it needs to initiate an abort for a given task.
 923  * This should only ever be called by an LLDD.
 924  */
 925 void sas_task_abort(struct sas_task *task)
 926 {
 927         struct scsi_cmnd *sc = task->uldd_task;
 928
 929         /* Escape for libsas internal commands */
 930         if (!sc) {
 931                 struct sas_task_slow *slow = task->slow_task;
 932
 933                 if (!slow)
 934                         return;
 935                 if (!del_timer(&slow->timer))
 936                         return;
 937                 slow->timer.function(slow->timer.data);
 938                 return;
 939         }
 940
 941         if (dev_is_sata(task->dev)) {
 942                 sas_ata_task_abort(task);
 943         } else {
 944                 struct request_queue *q = sc->device->request_queue;
 945                 unsigned long flags;
 946
 947                 spin_lock_irqsave(q->queue_lock, flags);
 948                 blk_abort_request(sc->request);
 949                 spin_unlock_irqrestore(q->queue_lock, flags);
 950         }
 951 }
 952
 953 void sas_target_destroy(struct scsi_target *starget)
 954 {
 955         struct domain_device *found_dev = starget->hostdata;
 956
 957         if (!found_dev)
 958                 return;
 959
 960         starget->hostdata = NULL;
 961         sas_put_device(found_dev);
 962 }
 963
 964 static void sas_parse_addr(u8 *sas_addr, const char *p)
 965 {
 966         int i;
 967         for (i = 0; i < SAS_ADDR_SIZE; i++) {
 968                 u8 h, l;
 969                 if (!*p)
 970                         break;
 971                 h = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
 972                 p++;
 973                 l = isdigit(*p) ? *p-'0' : toupper(*p)-'A'+10;
 974                 p++;
 975                 sas_addr[i] = (h<<4) | l;
 976         }
 977 }
 978
 979 #define SAS_STRING_ADDR_SIZE    16
 980
 981 int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
 982 {
 983         int res;
 984         const struct firmware *fw;
 985
 986         res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
 987         if (res)
 988                 return res;
 989
 990         if (fw->size < SAS_STRING_ADDR_SIZE) {
 991                 res = -ENODEV;
 992                 goto out;
 993         }
 994
 995         sas_parse_addr(addr, fw->data);
 996
 997 out:
 998         release_firmware(fw);
 999         return res;
1000 }
1001 EXPORT_SYMBOL_GPL(sas_request_addr);
1002
1003 EXPORT_SYMBOL_GPL(sas_queuecommand);
1004 EXPORT_SYMBOL_GPL(sas_target_alloc);
1005 EXPORT_SYMBOL_GPL(sas_slave_configure);
1006 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
1007 EXPORT_SYMBOL_GPL(sas_bios_param);
1008 EXPORT_SYMBOL_GPL(sas_task_abort);
1009 EXPORT_SYMBOL_GPL(sas_phy_reset);
1010 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
1011 EXPORT_SYMBOL_GPL(sas_eh_bus_reset_handler);
1012 EXPORT_SYMBOL_GPL(sas_target_destroy);
1013 EXPORT_SYMBOL_GPL(sas_ioctl);