SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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
  28 #include "sas_internal.h"
  29
  30 #include <scsi/scsi_host.h>
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_tcq.h>
  33 #include <scsi/scsi.h>
  34 #include <scsi/scsi_eh.h>
  35 #include <scsi/scsi_transport.h>
  36 #include <scsi/scsi_transport_sas.h>
  37 #include "../scsi_sas_internal.h"
  38 #include "../scsi_transport_api.h"
  39 #include "../scsi_priv.h"
  40
  41 #include <linux/err.h>
  42 #include <linux/blkdev.h>
  43 #include <linux/scatterlist.h>
  44
  45 /* ---------- SCSI Host glue ---------- */
  46
  47 #define TO_SAS_TASK(_scsi_cmd)  ((void *)(_scsi_cmd)->host_scribble)
  48 #define ASSIGN_SAS_TASK(_sc, _t) do { (_sc)->host_scribble = (void *) _t; } while (0)
  49
  50 static void sas_scsi_task_done(struct sas_task *task)
  51 {
  52         struct task_status_struct *ts = &task->task_status;
  53         struct scsi_cmnd *sc = task->uldd_task;
  54         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(sc->device->host);
  55         unsigned ts_flags = task->task_state_flags;
  56         int hs = 0, stat = 0;
  57
  58         if (unlikely(!sc)) {
  59                 SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
  60                 list_del_init(&task->list);
  61                 sas_free_task(task);
  62                 return;
  63         }
  64
  65         if (ts->resp == SAS_TASK_UNDELIVERED) {
  66                 /* transport error */
  67                 hs = DID_NO_CONNECT;
  68         } else { /* ts->resp == SAS_TASK_COMPLETE */
  69                 /* task delivered, what happened afterwards? */
  70                 switch (ts->stat) {
  71                 case SAS_DEV_NO_RESPONSE:
  72                 case SAS_INTERRUPTED:
  73                 case SAS_PHY_DOWN:
  74                 case SAS_NAK_R_ERR:
  75                 case SAS_OPEN_TO:
  76                         hs = DID_NO_CONNECT;
  77                         break;
  78                 case SAS_DATA_UNDERRUN:
  79                         scsi_set_resid(sc, ts->residual);
  80                         if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
  81                                 hs = DID_ERROR;
  82                         break;
  83                 case SAS_DATA_OVERRUN:
  84                         hs = DID_ERROR;
  85                         break;
  86                 case SAS_QUEUE_FULL:
  87                         hs = DID_SOFT_ERROR; /* retry */
  88                         break;
  89                 case SAS_DEVICE_UNKNOWN:
  90                         hs = DID_BAD_TARGET;
  91                         break;
  92                 case SAS_SG_ERR:
  93                         hs = DID_PARITY;
  94                         break;
  95                 case SAS_OPEN_REJECT:
  96                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
  97                                 hs = DID_SOFT_ERROR; /* retry */
  98                         else
  99                                 hs = DID_ERROR;
 100                         break;
 101                 case SAS_PROTO_RESPONSE:
 102                         SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
 103                                     "task; please report this\n",
 104                                     task->dev->port->ha->sas_ha_name);
 105                         break;
 106                 case SAS_ABORTED_TASK:
 107                         hs = DID_ABORT;
 108                         break;
 109                 case SAM_CHECK_COND:
 110                         memcpy(sc->sense_buffer, ts->buf,
 111                                max(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
 112                         stat = SAM_CHECK_COND;
 113                         break;
 114                 default:
 115                         stat = ts->stat;
 116                         break;
 117                 }
 118         }
 119         ASSIGN_SAS_TASK(sc, NULL);
 120         sc->result = (hs << 16) | stat;
 121         list_del_init(&task->list);
 122         sas_free_task(task);
 123         /* This is very ugly but this is how SCSI Core works. */
 124         if (ts_flags & SAS_TASK_STATE_ABORTED)
 125                 scsi_eh_finish_cmd(sc, &sas_ha->eh_done_q);
 126         else
 127                 sc->scsi_done(sc);
 128 }
 129
 130 static enum task_attribute sas_scsi_get_task_attr(struct scsi_cmnd *cmd)
 131 {
 132         enum task_attribute ta = TASK_ATTR_SIMPLE;
 133         if (cmd->request && blk_rq_tagged(cmd->request)) {
 134                 if (cmd->device->ordered_tags &&
 135                     (cmd->request->cmd_flags & REQ_HARDBARRIER))
 136                         ta = TASK_ATTR_ORDERED;
 137         }
 138         return ta;
 139 }
 140
 141 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 142                                                struct domain_device *dev,
 143                                                gfp_t gfp_flags)
 144 {
 145         struct sas_task *task = sas_alloc_task(gfp_flags);
 146         struct scsi_lun lun;
 147
 148         if (!task)
 149                 return NULL;
 150
 151         *(u32 *)cmd->sense_buffer = 0;
 152         task->uldd_task = cmd;
 153         ASSIGN_SAS_TASK(cmd, task);
 154
 155         task->dev = dev;
 156         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
 157
 158         task->ssp_task.retry_count = 1;
 159         int_to_scsilun(cmd->device->lun, &lun);
 160         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
 161         task->ssp_task.task_attr = sas_scsi_get_task_attr(cmd);
 162         memcpy(task->ssp_task.cdb, cmd->cmnd, 16);
 163
 164         task->scatter = scsi_sglist(cmd);
 165         task->num_scatter = scsi_sg_count(cmd);
 166         task->total_xfer_len = scsi_bufflen(cmd);
 167         task->data_dir = cmd->sc_data_direction;
 168
 169         task->task_done = sas_scsi_task_done;
 170
 171         return task;
 172 }
 173
 174 static int sas_queue_up(struct sas_task *task)
 175 {
 176         struct sas_ha_struct *sas_ha = task->dev->port->ha;
 177         struct scsi_core *core = &sas_ha->core;
 178         unsigned long flags;
 179         LIST_HEAD(list);
 180
 181         spin_lock_irqsave(&core->task_queue_lock, flags);
 182         if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
 183                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 184                 return -SAS_QUEUE_FULL;
 185         }
 186         list_add_tail(&task->list, &core->task_queue);
 187         core->task_queue_size += 1;
 188         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 189         wake_up_process(core->queue_thread);
 190
 191         return 0;
 192 }
 193
 194 /**
 195  * sas_queuecommand -- Enqueue a command for processing
 196  * @parameters: See SCSI Core documentation
 197  *
 198  * Note: XXX: Remove the host unlock/lock pair when SCSI Core can
 199  * call us without holding an IRQ spinlock...
 200  */
 201 int sas_queuecommand(struct scsi_cmnd *cmd,
 202                      void (*scsi_done)(struct scsi_cmnd *))
 203 {
 204         int res = 0;
 205         struct domain_device *dev = cmd_to_domain_dev(cmd);
 206         struct Scsi_Host *host = cmd->device->host;
 207         struct sas_internal *i = to_sas_internal(host->transportt);
 208
 209         spin_unlock_irq(host->host_lock);
 210
 211         {
 212                 struct sas_ha_struct *sas_ha = dev->port->ha;
 213                 struct sas_task *task;
 214
 215                 res = -ENOMEM;
 216                 task = sas_create_task(cmd, dev, GFP_ATOMIC);
 217                 if (!task)
 218                         goto out;
 219
 220                 cmd->scsi_done = scsi_done;
 221                 /* Queue up, Direct Mode or Task Collector Mode. */
 222                 if (sas_ha->lldd_max_execute_num < 2)
 223                         res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
 224                 else
 225                         res = sas_queue_up(task);
 226
 227                 /* Examine */
 228                 if (res) {
 229                         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
 230                         ASSIGN_SAS_TASK(cmd, NULL);
 231                         sas_free_task(task);
 232                         if (res == -SAS_QUEUE_FULL) {
 233                                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
 234                                 res = 0;
 235                                 scsi_done(cmd);
 236                         }
 237                         goto out;
 238                 }
 239         }
 240 out:
 241         spin_lock_irq(host->host_lock);
 242         return res;
 243 }
 244
 245 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 246 {
 247         struct scsi_cmnd *cmd, *n;
 248
 249         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 250                 if (cmd == my_cmd)
 251                         list_del_init(&cmd->eh_entry);
 252         }
 253 }
 254
 255 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 256                                      struct domain_device *dev)
 257 {
 258         struct scsi_cmnd *cmd, *n;
 259
 260         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 261                 struct domain_device *x = cmd_to_domain_dev(cmd);
 262
 263                 if (x == dev)
 264                         list_del_init(&cmd->eh_entry);
 265         }
 266 }
 267
 268 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 269                                       struct asd_sas_port *port)
 270 {
 271         struct scsi_cmnd *cmd, *n;
 272
 273         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 274                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 275                 struct asd_sas_port *x = dev->port;
 276
 277                 if (x == port)
 278                         list_del_init(&cmd->eh_entry);
 279         }
 280 }
 281
 282 enum task_disposition {
 283         TASK_IS_DONE,
 284         TASK_IS_ABORTED,
 285         TASK_IS_AT_LU,
 286         TASK_IS_NOT_AT_LU,
 287         TASK_ABORT_FAILED,
 288 };
 289
 290 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 291 {
 292         struct sas_ha_struct *ha = task->dev->port->ha;
 293         unsigned long flags;
 294         int i, res;
 295         struct sas_internal *si =
 296                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 297
 298         if (ha->lldd_max_execute_num > 1) {
 299                 struct scsi_core *core = &ha->core;
 300                 struct sas_task *t, *n;
 301
 302                 spin_lock_irqsave(&core->task_queue_lock, flags);
 303                 list_for_each_entry_safe(t, n, &core->task_queue, list) {
 304                         if (task == t) {
 305                                 list_del_init(&t->list);
 306                                 spin_unlock_irqrestore(&core->task_queue_lock,
 307                                                        flags);
 308                                 SAS_DPRINTK("%s: task 0x%p aborted from "
 309                                             "task_queue\n",
 310                                             __FUNCTION__, task);
 311                                 return TASK_IS_ABORTED;
 312                         }
 313                 }
 314                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 315         }
 316
 317         for (i = 0; i < 5; i++) {
 318                 SAS_DPRINTK("%s: aborting task 0x%p\n", __FUNCTION__, task);
 319                 res = si->dft->lldd_abort_task(task);
 320
 321                 spin_lock_irqsave(&task->task_state_lock, flags);
 322                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 323                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 324                         SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
 325                                     task);
 326                         return TASK_IS_DONE;
 327                 }
 328                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 329
 330                 if (res == TMF_RESP_FUNC_COMPLETE) {
 331                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 332                                     __FUNCTION__, task);
 333                         return TASK_IS_ABORTED;
 334                 } else if (si->dft->lldd_query_task) {
 335                         SAS_DPRINTK("%s: querying task 0x%p\n",
 336                                     __FUNCTION__, task);
 337                         res = si->dft->lldd_query_task(task);
 338                         switch (res) {
 339                         case TMF_RESP_FUNC_SUCC:
 340                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
 341                                             __FUNCTION__, task);
 342                                 return TASK_IS_AT_LU;
 343                         case TMF_RESP_FUNC_COMPLETE:
 344                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
 345                                             __FUNCTION__, task);
 346                                 return TASK_IS_NOT_AT_LU;
 347                         case TMF_RESP_FUNC_FAILED:
 348                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
 349                                                 __FUNCTION__, task);
 350                                 return TASK_ABORT_FAILED;
 351                         }
 352
 353                 }
 354         }
 355         return res;
 356 }
 357
 358 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 359 {
 360         int res = TMF_RESP_FUNC_FAILED;
 361         struct scsi_lun lun;
 362         struct sas_internal *i =
 363                 to_sas_internal(dev->port->ha->core.shost->transportt);
 364
 365         int_to_scsilun(cmd->device->lun, &lun);
 366
 367         SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
 368                     SAS_ADDR(dev->sas_addr),
 369                     cmd->device->lun);
 370
 371         if (i->dft->lldd_abort_task_set)
 372                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 373
 374         if (res == TMF_RESP_FUNC_FAILED) {
 375                 if (i->dft->lldd_clear_task_set)
 376                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 377         }
 378
 379         if (res == TMF_RESP_FUNC_FAILED) {
 380                 if (i->dft->lldd_lu_reset)
 381                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 382         }
 383
 384         return res;
 385 }
 386
 387 static int sas_recover_I_T(struct domain_device *dev)
 388 {
 389         int res = TMF_RESP_FUNC_FAILED;
 390         struct sas_internal *i =
 391                 to_sas_internal(dev->port->ha->core.shost->transportt);
 392
 393         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
 394                     SAS_ADDR(dev->sas_addr));
 395
 396         if (i->dft->lldd_I_T_nexus_reset)
 397                 res = i->dft->lldd_I_T_nexus_reset(dev);
 398
 399         return res;
 400 }
 401
 402 /* Find the sas_phy that's attached to this device */
 403 struct sas_phy *find_local_sas_phy(struct domain_device *dev)
 404 {
 405         struct domain_device *pdev = dev->parent;
 406         struct ex_phy *exphy = NULL;
 407         int i;
 408
 409         /* Directly attached device */
 410         if (!pdev)
 411                 return dev->port->phy;
 412
 413         /* Otherwise look in the expander */
 414         for (i = 0; i < pdev->ex_dev.num_phys; i++)
 415                 if (!memcmp(dev->sas_addr,
 416                             pdev->ex_dev.ex_phy[i].attached_sas_addr,
 417                             SAS_ADDR_SIZE)) {
 418                         exphy = &pdev->ex_dev.ex_phy[i];
 419                         break;
 420                 }
 421
 422         BUG_ON(!exphy);
 423         return exphy->phy;
 424 }
 425
 426 /* Attempt to send a LUN reset message to a device */
 427 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 428 {
 429         struct domain_device *dev = cmd_to_domain_dev(cmd);
 430         struct sas_internal *i =
 431                 to_sas_internal(dev->port->ha->core.shost->transportt);
 432         struct scsi_lun lun;
 433         int res;
 434
 435         int_to_scsilun(cmd->device->lun, &lun);
 436
 437         if (!i->dft->lldd_lu_reset)
 438                 return FAILED;
 439
 440         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 441         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 442                 return SUCCESS;
 443
 444         return FAILED;
 445 }
 446
 447 /* Attempt to send a phy (bus) reset */
 448 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
 449 {
 450         struct domain_device *dev = cmd_to_domain_dev(cmd);
 451         struct sas_phy *phy = find_local_sas_phy(dev);
 452         int res;
 453
 454         res = sas_phy_reset(phy, 1);
 455         if (res)
 456                 SAS_DPRINTK("Bus reset of %s failed 0x%x\n",
 457                             phy->dev.kobj.k_name,
 458                             res);
 459         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 460                 return SUCCESS;
 461
 462         return FAILED;
 463 }
 464
 465 /* Try to reset a device */
 466 static int try_to_reset_cmd_device(struct Scsi_Host *shost,
 467                                    struct scsi_cmnd *cmd)
 468 {
 469         int res;
 470
 471         if (!shost->hostt->eh_device_reset_handler)
 472                 goto try_bus_reset;
 473
 474         res = shost->hostt->eh_device_reset_handler(cmd);
 475         if (res == SUCCESS)
 476                 return res;
 477
 478 try_bus_reset:
 479         if (shost->hostt->eh_bus_reset_handler)
 480                 return shost->hostt->eh_bus_reset_handler(cmd);
 481
 482         return FAILED;
 483 }
 484
 485 static int sas_eh_handle_sas_errors(struct Scsi_Host *shost,
 486                                     struct list_head *work_q,
 487                                     struct list_head *done_q)
 488 {
 489         struct scsi_cmnd *cmd, *n;
 490         enum task_disposition res = TASK_IS_DONE;
 491         int tmf_resp, need_reset;
 492         struct sas_internal *i = to_sas_internal(shost->transportt);
 493         unsigned long flags;
 494         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 495
 496 Again:
 497         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 498                 struct sas_task *task = TO_SAS_TASK(cmd);
 499
 500                 if (!task)
 501                         continue;
 502
 503                 list_del_init(&cmd->eh_entry);
 504
 505                 spin_lock_irqsave(&task->task_state_lock, flags);
 506                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 507                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 508
 509                 SAS_DPRINTK("trying to find task 0x%p\n", task);
 510                 res = sas_scsi_find_task(task);
 511
 512                 cmd->eh_eflags = 0;
 513
 514                 switch (res) {
 515                 case TASK_IS_DONE:
 516                         SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
 517                                     task);
 518                         task->task_done(task);
 519                         if (need_reset)
 520                                 try_to_reset_cmd_device(shost, cmd);
 521                         continue;
 522                 case TASK_IS_ABORTED:
 523                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 524                                     __FUNCTION__, task);
 525                         task->task_done(task);
 526                         if (need_reset)
 527                                 try_to_reset_cmd_device(shost, cmd);
 528                         continue;
 529                 case TASK_IS_AT_LU:
 530                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
 531                         tmf_resp = sas_recover_lu(task->dev, cmd);
 532                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 533                                 SAS_DPRINTK("dev %016llx LU %x is "
 534                                             "recovered\n",
 535                                             SAS_ADDR(task->dev),
 536                                             cmd->device->lun);
 537                                 task->task_done(task);
 538                                 if (need_reset)
 539                                         try_to_reset_cmd_device(shost, cmd);
 540                                 sas_scsi_clear_queue_lu(work_q, cmd);
 541                                 goto Again;
 542                         }
 543                         /* fallthrough */
 544                 case TASK_IS_NOT_AT_LU:
 545                 case TASK_ABORT_FAILED:
 546                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
 547                                     task);
 548                         tmf_resp = sas_recover_I_T(task->dev);
 549                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 550                                 SAS_DPRINTK("I_T %016llx recovered\n",
 551                                             SAS_ADDR(task->dev->sas_addr));
 552                                 task->task_done(task);
 553                                 if (need_reset)
 554                                         try_to_reset_cmd_device(shost, cmd);
 555                                 sas_scsi_clear_queue_I_T(work_q, task->dev);
 556                                 goto Again;
 557                         }
 558                         /* Hammer time :-) */
 559                         if (i->dft->lldd_clear_nexus_port) {
 560                                 struct asd_sas_port *port = task->dev->port;
 561                                 SAS_DPRINTK("clearing nexus for port:%d\n",
 562                                             port->id);
 563                                 res = i->dft->lldd_clear_nexus_port(port);
 564                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 565                                         SAS_DPRINTK("clear nexus port:%d "
 566                                                     "succeeded\n", port->id);
 567                                         task->task_done(task);
 568                                         if (need_reset)
 569                                                 try_to_reset_cmd_device(shost, cmd);
 570                                         sas_scsi_clear_queue_port(work_q,
 571                                                                   port);
 572                                         goto Again;
 573                                 }
 574                         }
 575                         if (i->dft->lldd_clear_nexus_ha) {
 576                                 SAS_DPRINTK("clear nexus ha\n");
 577                                 res = i->dft->lldd_clear_nexus_ha(ha);
 578                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 579                                         SAS_DPRINTK("clear nexus ha "
 580                                                     "succeeded\n");
 581                                         task->task_done(task);
 582                                         if (need_reset)
 583                                                 try_to_reset_cmd_device(shost, cmd);
 584                                         goto out;
 585                                 }
 586                         }
 587                         /* If we are here -- this means that no amount
 588                          * of effort could recover from errors.  Quite
 589                          * possibly the HA just disappeared.
 590                          */
 591                         SAS_DPRINTK("error from  device %llx, LUN %x "
 592                                     "couldn't be recovered in any way\n",
 593                                     SAS_ADDR(task->dev->sas_addr),
 594                                     cmd->device->lun);
 595
 596                         task->task_done(task);
 597                         if (need_reset)
 598                                 try_to_reset_cmd_device(shost, cmd);
 599                         goto clear_q;
 600                 }
 601         }
 602 out:
 603         return list_empty(work_q);
 604 clear_q:
 605         SAS_DPRINTK("--- Exit %s -- clear_q\n", __FUNCTION__);
 606         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 607                 struct sas_task *task = TO_SAS_TASK(cmd);
 608                 list_del_init(&cmd->eh_entry);
 609                 task->task_done(task);
 610         }
 611         return list_empty(work_q);
 612 }
 613
 614 void sas_scsi_recover_host(struct Scsi_Host *shost)
 615 {
 616         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 617         unsigned long flags;
 618         LIST_HEAD(eh_work_q);
 619
 620         spin_lock_irqsave(shost->host_lock, flags);
 621         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
 622         spin_unlock_irqrestore(shost->host_lock, flags);
 623
 624         SAS_DPRINTK("Enter %s\n", __FUNCTION__);
 625         /*
 626          * Deal with commands that still have SAS tasks (i.e. they didn't
 627          * complete via the normal sas_task completion mechanism)
 628          */
 629         if (sas_eh_handle_sas_errors(shost, &eh_work_q, &ha->eh_done_q))
 630                 goto out;
 631
 632         /*
 633          * Now deal with SCSI commands that completed ok but have a an error
 634          * code (and hopefully sense data) attached.  This is roughly what
 635          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
 636          * command we see here has no sas_task and is thus unknown to the HA.
 637          */
 638         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
 639                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
 640
 641 out:
 642         scsi_eh_flush_done_q(&ha->eh_done_q);
 643         SAS_DPRINTK("--- Exit %s\n", __FUNCTION__);
 644         return;
 645 }
 646
 647 enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
 648 {
 649         struct sas_task *task = TO_SAS_TASK(cmd);
 650         unsigned long flags;
 651
 652         if (!task) {
 653                 cmd->timeout_per_command /= 2;
 654                 SAS_DPRINTK("command 0x%p, task 0x%p, gone: %s\n",
 655                             cmd, task, (cmd->timeout_per_command ?
 656                             "EH_RESET_TIMER" : "EH_NOT_HANDLED"));
 657                 if (!cmd->timeout_per_command)
 658                         return EH_NOT_HANDLED;
 659                 return EH_RESET_TIMER;
 660         }
 661
 662         spin_lock_irqsave(&task->task_state_lock, flags);
 663         BUG_ON(task->task_state_flags & SAS_TASK_STATE_ABORTED);
 664         if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 665                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 666                 SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
 667                             cmd, task);
 668                 return EH_HANDLED;
 669         }
 670         if (!(task->task_state_flags & SAS_TASK_AT_INITIATOR)) {
 671                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 672                 SAS_DPRINTK("command 0x%p, task 0x%p, not at initiator: "
 673                             "EH_RESET_TIMER\n",
 674                             cmd, task);
 675                 return EH_RESET_TIMER;
 676         }
 677         task->task_state_flags |= SAS_TASK_STATE_ABORTED;
 678         spin_unlock_irqrestore(&task->task_state_lock, flags);
 679
 680         SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_NOT_HANDLED\n",
 681                     cmd, task);
 682
 683         return EH_NOT_HANDLED;
 684 }
 685
 686 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
 687 {
 688         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
 689         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 690         struct domain_device *found_dev = NULL;
 691         int i;
 692         unsigned long flags;
 693
 694         spin_lock_irqsave(&ha->phy_port_lock, flags);
 695         for (i = 0; i < ha->num_phys; i++) {
 696                 struct asd_sas_port *port = ha->sas_port[i];
 697                 struct domain_device *dev;
 698
 699                 spin_lock(&port->dev_list_lock);
 700                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
 701                         if (rphy == dev->rphy) {
 702                                 found_dev = dev;
 703                                 spin_unlock(&port->dev_list_lock);
 704                                 goto found;
 705                         }
 706                 }
 707                 spin_unlock(&port->dev_list_lock);
 708         }
 709  found:
 710         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 711
 712         return found_dev;
 713 }
 714
 715 static inline struct domain_device *sas_find_target(struct scsi_target *starget)
 716 {
 717         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
 718
 719         return sas_find_dev_by_rphy(rphy);
 720 }
 721
 722 int sas_target_alloc(struct scsi_target *starget)
 723 {
 724         struct domain_device *found_dev = sas_find_target(starget);
 725
 726         if (!found_dev)
 727                 return -ENODEV;
 728
 729         starget->hostdata = found_dev;
 730         return 0;
 731 }
 732
 733 #define SAS_DEF_QD 32
 734 #define SAS_MAX_QD 64
 735
 736 int sas_slave_configure(struct scsi_device *scsi_dev)
 737 {
 738         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 739         struct sas_ha_struct *sas_ha;
 740
 741         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
 742
 743         sas_ha = dev->port->ha;
 744
 745         sas_read_port_mode_page(scsi_dev);
 746
 747         if (scsi_dev->tagged_supported) {
 748                 scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
 749                 scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
 750         } else {
 751                 SAS_DPRINTK("device %llx, LUN %x doesn't support "
 752                             "TCQ\n", SAS_ADDR(dev->sas_addr),
 753                             scsi_dev->lun);
 754                 scsi_dev->tagged_supported = 0;
 755                 scsi_set_tag_type(scsi_dev, 0);
 756                 scsi_deactivate_tcq(scsi_dev, 1);
 757         }
 758
 759         scsi_dev->allow_restart = 1;
 760
 761         return 0;
 762 }
 763
 764 void sas_slave_destroy(struct scsi_device *scsi_dev)
 765 {
 766 }
 767
 768 int sas_change_queue_depth(struct scsi_device *scsi_dev, int new_depth)
 769 {
 770         int res = min(new_depth, SAS_MAX_QD);
 771
 772         if (scsi_dev->tagged_supported)
 773                 scsi_adjust_queue_depth(scsi_dev, scsi_get_tag_type(scsi_dev),
 774                                         res);
 775         else {
 776                 struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 777                 sas_printk("device %llx LUN %x queue depth changed to 1\n",
 778                            SAS_ADDR(dev->sas_addr),
 779                            scsi_dev->lun);
 780                 scsi_adjust_queue_depth(scsi_dev, 0, 1);
 781                 res = 1;
 782         }
 783
 784         return res;
 785 }
 786
 787 int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
 788 {
 789         if (!scsi_dev->tagged_supported)
 790                 return 0;
 791
 792         scsi_deactivate_tcq(scsi_dev, 1);
 793
 794         scsi_set_tag_type(scsi_dev, qt);
 795         scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
 796
 797         return qt;
 798 }
 799
 800 int sas_bios_param(struct scsi_device *scsi_dev,
 801                           struct block_device *bdev,
 802                           sector_t capacity, int *hsc)
 803 {
 804         hsc[0] = 255;
 805         hsc[1] = 63;
 806         sector_div(capacity, 255*63);
 807         hsc[2] = capacity;
 808
 809         return 0;
 810 }
 811
 812 /* ---------- Task Collector Thread implementation ---------- */
 813
 814 static void sas_queue(struct sas_ha_struct *sas_ha)
 815 {
 816         struct scsi_core *core = &sas_ha->core;
 817         unsigned long flags;
 818         LIST_HEAD(q);
 819         int can_queue;
 820         int res;
 821         struct sas_internal *i = to_sas_internal(core->shost->transportt);
 822
 823         spin_lock_irqsave(&core->task_queue_lock, flags);
 824         while (!kthread_should_stop() &&
 825                !list_empty(&core->task_queue)) {
 826
 827                 can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
 828                 if (can_queue >= 0) {
 829                         can_queue = core->task_queue_size;
 830                         list_splice_init(&core->task_queue, &q);
 831                 } else {
 832                         struct list_head *a, *n;
 833
 834                         can_queue = sas_ha->lldd_queue_size;
 835                         list_for_each_safe(a, n, &core->task_queue) {
 836                                 list_move_tail(a, &q);
 837                                 if (--can_queue == 0)
 838                                         break;
 839                         }
 840                         can_queue = sas_ha->lldd_queue_size;
 841                 }
 842                 core->task_queue_size -= can_queue;
 843                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 844                 {
 845                         struct sas_task *task = list_entry(q.next,
 846                                                            struct sas_task,
 847                                                            list);
 848                         list_del_init(&q);
 849                         res = i->dft->lldd_execute_task(task, can_queue,
 850                                                         GFP_KERNEL);
 851                         if (unlikely(res))
 852                                 __list_add(&q, task->list.prev, &task->list);
 853                 }
 854                 spin_lock_irqsave(&core->task_queue_lock, flags);
 855                 if (res) {
 856                         list_splice_init(&q, &core->task_queue); /*at head*/
 857                         core->task_queue_size += can_queue;
 858                 }
 859         }
 860         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 861 }
 862
 863 /**
 864  * sas_queue_thread -- The Task Collector thread
 865  * @_sas_ha: pointer to struct sas_ha
 866  */
 867 static int sas_queue_thread(void *_sas_ha)
 868 {
 869         struct sas_ha_struct *sas_ha = _sas_ha;
 870
 871         current->flags |= PF_NOFREEZE;
 872
 873         while (1) {
 874                 set_current_state(TASK_INTERRUPTIBLE);
 875                 schedule();
 876                 sas_queue(sas_ha);
 877                 if (kthread_should_stop())
 878                         break;
 879         }
 880
 881         return 0;
 882 }
 883
 884 int sas_init_queue(struct sas_ha_struct *sas_ha)
 885 {
 886         struct scsi_core *core = &sas_ha->core;
 887
 888         spin_lock_init(&core->task_queue_lock);
 889         core->task_queue_size = 0;
 890         INIT_LIST_HEAD(&core->task_queue);
 891
 892         core->queue_thread = kthread_run(sas_queue_thread, sas_ha,
 893                                          "sas_queue_%d", core->shost->host_no);
 894         if (IS_ERR(core->queue_thread))
 895                 return PTR_ERR(core->queue_thread);
 896         return 0;
 897 }
 898
 899 void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
 900 {
 901         unsigned long flags;
 902         struct scsi_core *core = &sas_ha->core;
 903         struct sas_task *task, *n;
 904
 905         kthread_stop(core->queue_thread);
 906
 907         if (!list_empty(&core->task_queue))
 908                 SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
 909                             SAS_ADDR(sas_ha->sas_addr));
 910
 911         spin_lock_irqsave(&core->task_queue_lock, flags);
 912         list_for_each_entry_safe(task, n, &core->task_queue, list) {
 913                 struct scsi_cmnd *cmd = task->uldd_task;
 914
 915                 list_del_init(&task->list);
 916
 917                 ASSIGN_SAS_TASK(cmd, NULL);
 918                 sas_free_task(task);
 919                 cmd->result = DID_ABORT << 16;
 920                 cmd->scsi_done(cmd);
 921         }
 922         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 923 }
 924
 925 /*
 926  * Call the LLDD task abort routine directly.  This function is intended for
 927  * use by upper layers that need to tell the LLDD to abort a task.
 928  */
 929 int __sas_task_abort(struct sas_task *task)
 930 {
 931         struct sas_internal *si =
 932                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 933         unsigned long flags;
 934         int res;
 935
 936         spin_lock_irqsave(&task->task_state_lock, flags);
 937         if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
 938             task->task_state_flags & SAS_TASK_STATE_DONE) {
 939                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 940                 SAS_DPRINTK("%s: Task %p already finished.\n", __FUNCTION__,
 941                             task);
 942                 return 0;
 943         }
 944         task->task_state_flags |= SAS_TASK_STATE_ABORTED;
 945         spin_unlock_irqrestore(&task->task_state_lock, flags);
 946
 947         if (!si->dft->lldd_abort_task)
 948                 return -ENODEV;
 949
 950         res = si->dft->lldd_abort_task(task);
 951
 952         spin_lock_irqsave(&task->task_state_lock, flags);
 953         if ((task->task_state_flags & SAS_TASK_STATE_DONE) ||
 954             (res == TMF_RESP_FUNC_COMPLETE))
 955         {
 956                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 957                 task->task_done(task);
 958                 return 0;
 959         }
 960
 961         if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
 962                 task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
 963         spin_unlock_irqrestore(&task->task_state_lock, flags);
 964
 965         return -EAGAIN;
 966 }
 967
 968 /*
 969  * Tell an upper layer that it needs to initiate an abort for a given task.
 970  * This should only ever be called by an LLDD.
 971  */
 972 void sas_task_abort(struct sas_task *task)
 973 {
 974         struct scsi_cmnd *sc = task->uldd_task;
 975
 976         /* Escape for libsas internal commands */
 977         if (!sc) {
 978                 if (!del_timer(&task->timer))
 979                         return;
 980                 task->timer.function(task->timer.data);
 981                 return;
 982         }
 983
 984         scsi_req_abort_cmd(sc);
 985         scsi_schedule_eh(sc->device->host);
 986 }
 987
 988 EXPORT_SYMBOL_GPL(sas_queuecommand);
 989 EXPORT_SYMBOL_GPL(sas_target_alloc);
 990 EXPORT_SYMBOL_GPL(sas_slave_configure);
 991 EXPORT_SYMBOL_GPL(sas_slave_destroy);
 992 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
 993 EXPORT_SYMBOL_GPL(sas_change_queue_type);
 994 EXPORT_SYMBOL_GPL(sas_bios_param);
 995 EXPORT_SYMBOL_GPL(__sas_task_abort);
 996 EXPORT_SYMBOL_GPL(sas_task_abort);
 997 EXPORT_SYMBOL_GPL(sas_phy_reset);
 998 EXPORT_SYMBOL_GPL(sas_phy_enable);
 999 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
1000 EXPORT_SYMBOL_GPL(sas_eh_bus_reset_handler);