git.oblomov.eu Git - 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 "sas_internal.h"
  27
  28 #include <scsi/scsi_host.h>
  29 #include <scsi/scsi_device.h>
  30 #include <scsi/scsi_tcq.h>
  31 #include <scsi/scsi.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_transport.h>
  34 #include <scsi/scsi_transport_sas.h>
  35 #include "../scsi_sas_internal.h"
  36 #include "../scsi_transport_api.h"
  37 #include "../scsi_priv.h"
  38
  39 #include <linux/err.h>
  40 #include <linux/blkdev.h>
  41 #include <linux/scatterlist.h>
  42
  43 /* ---------- SCSI Host glue ---------- */
  44
  45 #define TO_SAS_TASK(_scsi_cmd)  ((void *)(_scsi_cmd)->host_scribble)
  46 #define ASSIGN_SAS_TASK(_sc, _t) do { (_sc)->host_scribble = (void *) _t; } while (0)
  47
  48 static void sas_scsi_task_done(struct sas_task *task)
  49 {
  50         struct task_status_struct *ts = &task->task_status;
  51         struct scsi_cmnd *sc = task->uldd_task;
  52         struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(sc->device->host);
  53         unsigned ts_flags = task->task_state_flags;
  54         int hs = 0, stat = 0;
  55
  56         if (unlikely(!sc)) {
  57                 SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
  58                 list_del_init(&task->list);
  59                 sas_free_task(task);
  60                 return;
  61         }
  62
  63         if (ts->resp == SAS_TASK_UNDELIVERED) {
  64                 /* transport error */
  65                 hs = DID_NO_CONNECT;
  66         } else { /* ts->resp == SAS_TASK_COMPLETE */
  67                 /* task delivered, what happened afterwards? */
  68                 switch (ts->stat) {
  69                 case SAS_DEV_NO_RESPONSE:
  70                 case SAS_INTERRUPTED:
  71                 case SAS_PHY_DOWN:
  72                 case SAS_NAK_R_ERR:
  73                 case SAS_OPEN_TO:
  74                         hs = DID_NO_CONNECT;
  75                         break;
  76                 case SAS_DATA_UNDERRUN:
  77                         sc->resid = ts->residual;
  78                         if (sc->request_bufflen - sc->resid < sc->underflow)
  79                                 hs = DID_ERROR;
  80                         break;
  81                 case SAS_DATA_OVERRUN:
  82                         hs = DID_ERROR;
  83                         break;
  84                 case SAS_QUEUE_FULL:
  85                         hs = DID_SOFT_ERROR; /* retry */
  86                         break;
  87                 case SAS_DEVICE_UNKNOWN:
  88                         hs = DID_BAD_TARGET;
  89                         break;
  90                 case SAS_SG_ERR:
  91                         hs = DID_PARITY;
  92                         break;
  93                 case SAS_OPEN_REJECT:
  94                         if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
  95                                 hs = DID_SOFT_ERROR; /* retry */
  96                         else
  97                                 hs = DID_ERROR;
  98                         break;
  99                 case SAS_PROTO_RESPONSE:
 100                         SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
 101                                     "task; please report this\n",
 102                                     task->dev->port->ha->sas_ha_name);
 103                         break;
 104                 case SAS_ABORTED_TASK:
 105                         hs = DID_ABORT;
 106                         break;
 107                 case SAM_CHECK_COND:
 108                         memcpy(sc->sense_buffer, ts->buf,
 109                                max(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
 110                         stat = SAM_CHECK_COND;
 111                         break;
 112                 default:
 113                         stat = ts->stat;
 114                         break;
 115                 }
 116         }
 117         ASSIGN_SAS_TASK(sc, NULL);
 118         sc->result = (hs << 16) | stat;
 119         list_del_init(&task->list);
 120         sas_free_task(task);
 121         /* This is very ugly but this is how SCSI Core works. */
 122         if (ts_flags & SAS_TASK_STATE_ABORTED)
 123                 scsi_eh_finish_cmd(sc, &sas_ha->eh_done_q);
 124         else
 125                 sc->scsi_done(sc);
 126 }
 127
 128 static enum task_attribute sas_scsi_get_task_attr(struct scsi_cmnd *cmd)
 129 {
 130         enum task_attribute ta = TASK_ATTR_SIMPLE;
 131         if (cmd->request && blk_rq_tagged(cmd->request)) {
 132                 if (cmd->device->ordered_tags &&
 133                     (cmd->request->cmd_flags & REQ_HARDBARRIER))
 134                         ta = TASK_ATTR_ORDERED;
 135         }
 136         return ta;
 137 }
 138
 139 static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 140                                                struct domain_device *dev,
 141                                                gfp_t gfp_flags)
 142 {
 143         struct sas_task *task = sas_alloc_task(gfp_flags);
 144         struct scsi_lun lun;
 145
 146         if (!task)
 147                 return NULL;
 148
 149         *(u32 *)cmd->sense_buffer = 0;
 150         task->uldd_task = cmd;
 151         ASSIGN_SAS_TASK(cmd, task);
 152
 153         task->dev = dev;
 154         task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
 155
 156         task->ssp_task.retry_count = 1;
 157         int_to_scsilun(cmd->device->lun, &lun);
 158         memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
 159         task->ssp_task.task_attr = sas_scsi_get_task_attr(cmd);
 160         memcpy(task->ssp_task.cdb, cmd->cmnd, 16);
 161
 162         task->scatter = cmd->request_buffer;
 163         task->num_scatter = cmd->use_sg;
 164         task->total_xfer_len = cmd->request_bufflen;
 165         task->data_dir = cmd->sc_data_direction;
 166
 167         task->task_done = sas_scsi_task_done;
 168
 169         return task;
 170 }
 171
 172 static int sas_queue_up(struct sas_task *task)
 173 {
 174         struct sas_ha_struct *sas_ha = task->dev->port->ha;
 175         struct scsi_core *core = &sas_ha->core;
 176         unsigned long flags;
 177         LIST_HEAD(list);
 178
 179         spin_lock_irqsave(&core->task_queue_lock, flags);
 180         if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
 181                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 182                 return -SAS_QUEUE_FULL;
 183         }
 184         list_add_tail(&task->list, &core->task_queue);
 185         core->task_queue_size += 1;
 186         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 187         up(&core->queue_thread_sema);
 188
 189         return 0;
 190 }
 191
 192 /**
 193  * sas_queuecommand -- Enqueue a command for processing
 194  * @parameters: See SCSI Core documentation
 195  *
 196  * Note: XXX: Remove the host unlock/lock pair when SCSI Core can
 197  * call us without holding an IRQ spinlock...
 198  */
 199 int sas_queuecommand(struct scsi_cmnd *cmd,
 200                      void (*scsi_done)(struct scsi_cmnd *))
 201 {
 202         int res = 0;
 203         struct domain_device *dev = cmd_to_domain_dev(cmd);
 204         struct Scsi_Host *host = cmd->device->host;
 205         struct sas_internal *i = to_sas_internal(host->transportt);
 206
 207         spin_unlock_irq(host->host_lock);
 208
 209         {
 210                 struct sas_ha_struct *sas_ha = dev->port->ha;
 211                 struct sas_task *task;
 212
 213                 res = -ENOMEM;
 214                 task = sas_create_task(cmd, dev, GFP_ATOMIC);
 215                 if (!task)
 216                         goto out;
 217
 218                 cmd->scsi_done = scsi_done;
 219                 /* Queue up, Direct Mode or Task Collector Mode. */
 220                 if (sas_ha->lldd_max_execute_num < 2)
 221                         res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
 222                 else
 223                         res = sas_queue_up(task);
 224
 225                 /* Examine */
 226                 if (res) {
 227                         SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
 228                         ASSIGN_SAS_TASK(cmd, NULL);
 229                         sas_free_task(task);
 230                         if (res == -SAS_QUEUE_FULL) {
 231                                 cmd->result = DID_SOFT_ERROR << 16; /* retry */
 232                                 res = 0;
 233                                 scsi_done(cmd);
 234                         }
 235                         goto out;
 236                 }
 237         }
 238 out:
 239         spin_lock_irq(host->host_lock);
 240         return res;
 241 }
 242
 243 static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
 244 {
 245         struct scsi_cmnd *cmd, *n;
 246
 247         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 248                 if (cmd == my_cmd)
 249                         list_del_init(&cmd->eh_entry);
 250         }
 251 }
 252
 253 static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
 254                                      struct domain_device *dev)
 255 {
 256         struct scsi_cmnd *cmd, *n;
 257
 258         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 259                 struct domain_device *x = cmd_to_domain_dev(cmd);
 260
 261                 if (x == dev)
 262                         list_del_init(&cmd->eh_entry);
 263         }
 264 }
 265
 266 static void sas_scsi_clear_queue_port(struct list_head *error_q,
 267                                       struct asd_sas_port *port)
 268 {
 269         struct scsi_cmnd *cmd, *n;
 270
 271         list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
 272                 struct domain_device *dev = cmd_to_domain_dev(cmd);
 273                 struct asd_sas_port *x = dev->port;
 274
 275                 if (x == port)
 276                         list_del_init(&cmd->eh_entry);
 277         }
 278 }
 279
 280 enum task_disposition {
 281         TASK_IS_DONE,
 282         TASK_IS_ABORTED,
 283         TASK_IS_AT_LU,
 284         TASK_IS_NOT_AT_LU,
 285         TASK_ABORT_FAILED,
 286 };
 287
 288 static enum task_disposition sas_scsi_find_task(struct sas_task *task)
 289 {
 290         struct sas_ha_struct *ha = task->dev->port->ha;
 291         unsigned long flags;
 292         int i, res;
 293         struct sas_internal *si =
 294                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 295
 296         if (ha->lldd_max_execute_num > 1) {
 297                 struct scsi_core *core = &ha->core;
 298                 struct sas_task *t, *n;
 299
 300                 spin_lock_irqsave(&core->task_queue_lock, flags);
 301                 list_for_each_entry_safe(t, n, &core->task_queue, list) {
 302                         if (task == t) {
 303                                 list_del_init(&t->list);
 304                                 spin_unlock_irqrestore(&core->task_queue_lock,
 305                                                        flags);
 306                                 SAS_DPRINTK("%s: task 0x%p aborted from "
 307                                             "task_queue\n",
 308                                             __FUNCTION__, task);
 309                                 return TASK_IS_ABORTED;
 310                         }
 311                 }
 312                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 313         }
 314
 315         for (i = 0; i < 5; i++) {
 316                 SAS_DPRINTK("%s: aborting task 0x%p\n", __FUNCTION__, task);
 317                 res = si->dft->lldd_abort_task(task);
 318
 319                 spin_lock_irqsave(&task->task_state_lock, flags);
 320                 if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 321                         spin_unlock_irqrestore(&task->task_state_lock, flags);
 322                         SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
 323                                     task);
 324                         return TASK_IS_DONE;
 325                 }
 326                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 327
 328                 if (res == TMF_RESP_FUNC_COMPLETE) {
 329                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 330                                     __FUNCTION__, task);
 331                         return TASK_IS_ABORTED;
 332                 } else if (si->dft->lldd_query_task) {
 333                         SAS_DPRINTK("%s: querying task 0x%p\n",
 334                                     __FUNCTION__, task);
 335                         res = si->dft->lldd_query_task(task);
 336                         switch (res) {
 337                         case TMF_RESP_FUNC_SUCC:
 338                                 SAS_DPRINTK("%s: task 0x%p at LU\n",
 339                                             __FUNCTION__, task);
 340                                 return TASK_IS_AT_LU;
 341                         case TMF_RESP_FUNC_COMPLETE:
 342                                 SAS_DPRINTK("%s: task 0x%p not at LU\n",
 343                                             __FUNCTION__, task);
 344                                 return TASK_IS_NOT_AT_LU;
 345                         case TMF_RESP_FUNC_FAILED:
 346                                 SAS_DPRINTK("%s: task 0x%p failed to abort\n",
 347                                                 __FUNCTION__, task);
 348                                 return TASK_ABORT_FAILED;
 349                         }
 350
 351                 }
 352         }
 353         return res;
 354 }
 355
 356 static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
 357 {
 358         int res = TMF_RESP_FUNC_FAILED;
 359         struct scsi_lun lun;
 360         struct sas_internal *i =
 361                 to_sas_internal(dev->port->ha->core.shost->transportt);
 362
 363         int_to_scsilun(cmd->device->lun, &lun);
 364
 365         SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
 366                     SAS_ADDR(dev->sas_addr),
 367                     cmd->device->lun);
 368
 369         if (i->dft->lldd_abort_task_set)
 370                 res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
 371
 372         if (res == TMF_RESP_FUNC_FAILED) {
 373                 if (i->dft->lldd_clear_task_set)
 374                         res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
 375         }
 376
 377         if (res == TMF_RESP_FUNC_FAILED) {
 378                 if (i->dft->lldd_lu_reset)
 379                         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 380         }
 381
 382         return res;
 383 }
 384
 385 static int sas_recover_I_T(struct domain_device *dev)
 386 {
 387         int res = TMF_RESP_FUNC_FAILED;
 388         struct sas_internal *i =
 389                 to_sas_internal(dev->port->ha->core.shost->transportt);
 390
 391         SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
 392                     SAS_ADDR(dev->sas_addr));
 393
 394         if (i->dft->lldd_I_T_nexus_reset)
 395                 res = i->dft->lldd_I_T_nexus_reset(dev);
 396
 397         return res;
 398 }
 399
 400 /* Find the sas_phy that's attached to this device */
 401 struct sas_phy *find_local_sas_phy(struct domain_device *dev)
 402 {
 403         struct domain_device *pdev = dev->parent;
 404         struct ex_phy *exphy = NULL;
 405         int i;
 406
 407         /* Directly attached device */
 408         if (!pdev)
 409                 return dev->port->phy;
 410
 411         /* Otherwise look in the expander */
 412         for (i = 0; i < pdev->ex_dev.num_phys; i++)
 413                 if (!memcmp(dev->sas_addr,
 414                             pdev->ex_dev.ex_phy[i].attached_sas_addr,
 415                             SAS_ADDR_SIZE)) {
 416                         exphy = &pdev->ex_dev.ex_phy[i];
 417                         break;
 418                 }
 419
 420         BUG_ON(!exphy);
 421         return exphy->phy;
 422 }
 423
 424 /* Attempt to send a LUN reset message to a device */
 425 int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
 426 {
 427         struct domain_device *dev = cmd_to_domain_dev(cmd);
 428         struct sas_internal *i =
 429                 to_sas_internal(dev->port->ha->core.shost->transportt);
 430         struct scsi_lun lun;
 431         int res;
 432
 433         int_to_scsilun(cmd->device->lun, &lun);
 434
 435         if (!i->dft->lldd_lu_reset)
 436                 return FAILED;
 437
 438         res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
 439         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 440                 return SUCCESS;
 441
 442         return FAILED;
 443 }
 444
 445 /* Attempt to send a phy (bus) reset */
 446 int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd)
 447 {
 448         struct domain_device *dev = cmd_to_domain_dev(cmd);
 449         struct sas_phy *phy = find_local_sas_phy(dev);
 450         int res;
 451
 452         res = sas_phy_reset(phy, 1);
 453         if (res)
 454                 SAS_DPRINTK("Bus reset of %s failed 0x%x\n",
 455                             phy->dev.kobj.k_name,
 456                             res);
 457         if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
 458                 return SUCCESS;
 459
 460         return FAILED;
 461 }
 462
 463 /* Try to reset a device */
 464 static int try_to_reset_cmd_device(struct Scsi_Host *shost,
 465                                    struct scsi_cmnd *cmd)
 466 {
 467         int res;
 468
 469         if (!shost->hostt->eh_device_reset_handler)
 470                 goto try_bus_reset;
 471
 472         res = shost->hostt->eh_device_reset_handler(cmd);
 473         if (res == SUCCESS)
 474                 return res;
 475
 476 try_bus_reset:
 477         if (shost->hostt->eh_bus_reset_handler)
 478                 return shost->hostt->eh_bus_reset_handler(cmd);
 479
 480         return FAILED;
 481 }
 482
 483 static int sas_eh_handle_sas_errors(struct Scsi_Host *shost,
 484                                     struct list_head *work_q,
 485                                     struct list_head *done_q)
 486 {
 487         struct scsi_cmnd *cmd, *n;
 488         enum task_disposition res = TASK_IS_DONE;
 489         int tmf_resp, need_reset;
 490         struct sas_internal *i = to_sas_internal(shost->transportt);
 491         unsigned long flags;
 492         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 493
 494 Again:
 495         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 496                 struct sas_task *task = TO_SAS_TASK(cmd);
 497
 498                 if (!task)
 499                         continue;
 500
 501                 list_del_init(&cmd->eh_entry);
 502
 503                 spin_lock_irqsave(&task->task_state_lock, flags);
 504                 need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
 505                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 506
 507                 SAS_DPRINTK("trying to find task 0x%p\n", task);
 508                 res = sas_scsi_find_task(task);
 509
 510                 cmd->eh_eflags = 0;
 511
 512                 switch (res) {
 513                 case TASK_IS_DONE:
 514                         SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
 515                                     task);
 516                         task->task_done(task);
 517                         if (need_reset)
 518                                 try_to_reset_cmd_device(shost, cmd);
 519                         continue;
 520                 case TASK_IS_ABORTED:
 521                         SAS_DPRINTK("%s: task 0x%p is aborted\n",
 522                                     __FUNCTION__, task);
 523                         task->task_done(task);
 524                         if (need_reset)
 525                                 try_to_reset_cmd_device(shost, cmd);
 526                         continue;
 527                 case TASK_IS_AT_LU:
 528                         SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
 529                         tmf_resp = sas_recover_lu(task->dev, cmd);
 530                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 531                                 SAS_DPRINTK("dev %016llx LU %x is "
 532                                             "recovered\n",
 533                                             SAS_ADDR(task->dev),
 534                                             cmd->device->lun);
 535                                 task->task_done(task);
 536                                 if (need_reset)
 537                                         try_to_reset_cmd_device(shost, cmd);
 538                                 sas_scsi_clear_queue_lu(work_q, cmd);
 539                                 goto Again;
 540                         }
 541                         /* fallthrough */
 542                 case TASK_IS_NOT_AT_LU:
 543                 case TASK_ABORT_FAILED:
 544                         SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
 545                                     task);
 546                         tmf_resp = sas_recover_I_T(task->dev);
 547                         if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
 548                                 SAS_DPRINTK("I_T %016llx recovered\n",
 549                                             SAS_ADDR(task->dev->sas_addr));
 550                                 task->task_done(task);
 551                                 if (need_reset)
 552                                         try_to_reset_cmd_device(shost, cmd);
 553                                 sas_scsi_clear_queue_I_T(work_q, task->dev);
 554                                 goto Again;
 555                         }
 556                         /* Hammer time :-) */
 557                         if (i->dft->lldd_clear_nexus_port) {
 558                                 struct asd_sas_port *port = task->dev->port;
 559                                 SAS_DPRINTK("clearing nexus for port:%d\n",
 560                                             port->id);
 561                                 res = i->dft->lldd_clear_nexus_port(port);
 562                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 563                                         SAS_DPRINTK("clear nexus port:%d "
 564                                                     "succeeded\n", port->id);
 565                                         task->task_done(task);
 566                                         if (need_reset)
 567                                                 try_to_reset_cmd_device(shost, cmd);
 568                                         sas_scsi_clear_queue_port(work_q,
 569                                                                   port);
 570                                         goto Again;
 571                                 }
 572                         }
 573                         if (i->dft->lldd_clear_nexus_ha) {
 574                                 SAS_DPRINTK("clear nexus ha\n");
 575                                 res = i->dft->lldd_clear_nexus_ha(ha);
 576                                 if (res == TMF_RESP_FUNC_COMPLETE) {
 577                                         SAS_DPRINTK("clear nexus ha "
 578                                                     "succeeded\n");
 579                                         task->task_done(task);
 580                                         if (need_reset)
 581                                                 try_to_reset_cmd_device(shost, cmd);
 582                                         goto out;
 583                                 }
 584                         }
 585                         /* If we are here -- this means that no amount
 586                          * of effort could recover from errors.  Quite
 587                          * possibly the HA just disappeared.
 588                          */
 589                         SAS_DPRINTK("error from  device %llx, LUN %x "
 590                                     "couldn't be recovered in any way\n",
 591                                     SAS_ADDR(task->dev->sas_addr),
 592                                     cmd->device->lun);
 593
 594                         task->task_done(task);
 595                         if (need_reset)
 596                                 try_to_reset_cmd_device(shost, cmd);
 597                         goto clear_q;
 598                 }
 599         }
 600 out:
 601         return list_empty(work_q);
 602 clear_q:
 603         SAS_DPRINTK("--- Exit %s -- clear_q\n", __FUNCTION__);
 604         list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
 605                 struct sas_task *task = TO_SAS_TASK(cmd);
 606                 list_del_init(&cmd->eh_entry);
 607                 task->task_done(task);
 608         }
 609         return list_empty(work_q);
 610 }
 611
 612 void sas_scsi_recover_host(struct Scsi_Host *shost)
 613 {
 614         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 615         unsigned long flags;
 616         LIST_HEAD(eh_work_q);
 617
 618         spin_lock_irqsave(shost->host_lock, flags);
 619         list_splice_init(&shost->eh_cmd_q, &eh_work_q);
 620         spin_unlock_irqrestore(shost->host_lock, flags);
 621
 622         SAS_DPRINTK("Enter %s\n", __FUNCTION__);
 623         /*
 624          * Deal with commands that still have SAS tasks (i.e. they didn't
 625          * complete via the normal sas_task completion mechanism)
 626          */
 627         if (sas_eh_handle_sas_errors(shost, &eh_work_q, &ha->eh_done_q))
 628                 goto out;
 629
 630         /*
 631          * Now deal with SCSI commands that completed ok but have a an error
 632          * code (and hopefully sense data) attached.  This is roughly what
 633          * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
 634          * command we see here has no sas_task and is thus unknown to the HA.
 635          */
 636         if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
 637                 scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
 638
 639 out:
 640         scsi_eh_flush_done_q(&ha->eh_done_q);
 641         SAS_DPRINTK("--- Exit %s\n", __FUNCTION__);
 642         return;
 643 }
 644
 645 enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
 646 {
 647         struct sas_task *task = TO_SAS_TASK(cmd);
 648         unsigned long flags;
 649
 650         if (!task) {
 651                 cmd->timeout_per_command /= 2;
 652                 SAS_DPRINTK("command 0x%p, task 0x%p, gone: %s\n",
 653                             cmd, task, (cmd->timeout_per_command ?
 654                             "EH_RESET_TIMER" : "EH_NOT_HANDLED"));
 655                 if (!cmd->timeout_per_command)
 656                         return EH_NOT_HANDLED;
 657                 return EH_RESET_TIMER;
 658         }
 659
 660         spin_lock_irqsave(&task->task_state_lock, flags);
 661         BUG_ON(task->task_state_flags & SAS_TASK_STATE_ABORTED);
 662         if (task->task_state_flags & SAS_TASK_STATE_DONE) {
 663                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 664                 SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
 665                             cmd, task);
 666                 return EH_HANDLED;
 667         }
 668         if (!(task->task_state_flags & SAS_TASK_AT_INITIATOR)) {
 669                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 670                 SAS_DPRINTK("command 0x%p, task 0x%p, not at initiator: "
 671                             "EH_RESET_TIMER\n",
 672                             cmd, task);
 673                 return EH_RESET_TIMER;
 674         }
 675         task->task_state_flags |= SAS_TASK_STATE_ABORTED;
 676         spin_unlock_irqrestore(&task->task_state_lock, flags);
 677
 678         SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_NOT_HANDLED\n",
 679                     cmd, task);
 680
 681         return EH_NOT_HANDLED;
 682 }
 683
 684 struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
 685 {
 686         struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
 687         struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
 688         struct domain_device *found_dev = NULL;
 689         int i;
 690         unsigned long flags;
 691
 692         spin_lock_irqsave(&ha->phy_port_lock, flags);
 693         for (i = 0; i < ha->num_phys; i++) {
 694                 struct asd_sas_port *port = ha->sas_port[i];
 695                 struct domain_device *dev;
 696
 697                 spin_lock(&port->dev_list_lock);
 698                 list_for_each_entry(dev, &port->dev_list, dev_list_node) {
 699                         if (rphy == dev->rphy) {
 700                                 found_dev = dev;
 701                                 spin_unlock(&port->dev_list_lock);
 702                                 goto found;
 703                         }
 704                 }
 705                 spin_unlock(&port->dev_list_lock);
 706         }
 707  found:
 708         spin_unlock_irqrestore(&ha->phy_port_lock, flags);
 709
 710         return found_dev;
 711 }
 712
 713 static inline struct domain_device *sas_find_target(struct scsi_target *starget)
 714 {
 715         struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
 716
 717         return sas_find_dev_by_rphy(rphy);
 718 }
 719
 720 int sas_target_alloc(struct scsi_target *starget)
 721 {
 722         struct domain_device *found_dev = sas_find_target(starget);
 723
 724         if (!found_dev)
 725                 return -ENODEV;
 726
 727         starget->hostdata = found_dev;
 728         return 0;
 729 }
 730
 731 #define SAS_DEF_QD 32
 732 #define SAS_MAX_QD 64
 733
 734 int sas_slave_configure(struct scsi_device *scsi_dev)
 735 {
 736         struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 737         struct sas_ha_struct *sas_ha;
 738
 739         BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
 740
 741         sas_ha = dev->port->ha;
 742
 743         sas_read_port_mode_page(scsi_dev);
 744
 745         if (scsi_dev->tagged_supported) {
 746                 scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
 747                 scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
 748         } else {
 749                 SAS_DPRINTK("device %llx, LUN %x doesn't support "
 750                             "TCQ\n", SAS_ADDR(dev->sas_addr),
 751                             scsi_dev->lun);
 752                 scsi_dev->tagged_supported = 0;
 753                 scsi_set_tag_type(scsi_dev, 0);
 754                 scsi_deactivate_tcq(scsi_dev, 1);
 755         }
 756
 757         scsi_dev->allow_restart = 1;
 758
 759         return 0;
 760 }
 761
 762 void sas_slave_destroy(struct scsi_device *scsi_dev)
 763 {
 764 }
 765
 766 int sas_change_queue_depth(struct scsi_device *scsi_dev, int new_depth)
 767 {
 768         int res = min(new_depth, SAS_MAX_QD);
 769
 770         if (scsi_dev->tagged_supported)
 771                 scsi_adjust_queue_depth(scsi_dev, scsi_get_tag_type(scsi_dev),
 772                                         res);
 773         else {
 774                 struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
 775                 sas_printk("device %llx LUN %x queue depth changed to 1\n",
 776                            SAS_ADDR(dev->sas_addr),
 777                            scsi_dev->lun);
 778                 scsi_adjust_queue_depth(scsi_dev, 0, 1);
 779                 res = 1;
 780         }
 781
 782         return res;
 783 }
 784
 785 int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
 786 {
 787         if (!scsi_dev->tagged_supported)
 788                 return 0;
 789
 790         scsi_deactivate_tcq(scsi_dev, 1);
 791
 792         scsi_set_tag_type(scsi_dev, qt);
 793         scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
 794
 795         return qt;
 796 }
 797
 798 int sas_bios_param(struct scsi_device *scsi_dev,
 799                           struct block_device *bdev,
 800                           sector_t capacity, int *hsc)
 801 {
 802         hsc[0] = 255;
 803         hsc[1] = 63;
 804         sector_div(capacity, 255*63);
 805         hsc[2] = capacity;
 806
 807         return 0;
 808 }
 809
 810 /* ---------- Task Collector Thread implementation ---------- */
 811
 812 static void sas_queue(struct sas_ha_struct *sas_ha)
 813 {
 814         struct scsi_core *core = &sas_ha->core;
 815         unsigned long flags;
 816         LIST_HEAD(q);
 817         int can_queue;
 818         int res;
 819         struct sas_internal *i = to_sas_internal(core->shost->transportt);
 820
 821         spin_lock_irqsave(&core->task_queue_lock, flags);
 822         while (!core->queue_thread_kill &&
 823                !list_empty(&core->task_queue)) {
 824
 825                 can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
 826                 if (can_queue >= 0) {
 827                         can_queue = core->task_queue_size;
 828                         list_splice_init(&core->task_queue, &q);
 829                 } else {
 830                         struct list_head *a, *n;
 831
 832                         can_queue = sas_ha->lldd_queue_size;
 833                         list_for_each_safe(a, n, &core->task_queue) {
 834                                 list_move_tail(a, &q);
 835                                 if (--can_queue == 0)
 836                                         break;
 837                         }
 838                         can_queue = sas_ha->lldd_queue_size;
 839                 }
 840                 core->task_queue_size -= can_queue;
 841                 spin_unlock_irqrestore(&core->task_queue_lock, flags);
 842                 {
 843                         struct sas_task *task = list_entry(q.next,
 844                                                            struct sas_task,
 845                                                            list);
 846                         list_del_init(&q);
 847                         res = i->dft->lldd_execute_task(task, can_queue,
 848                                                         GFP_KERNEL);
 849                         if (unlikely(res))
 850                                 __list_add(&q, task->list.prev, &task->list);
 851                 }
 852                 spin_lock_irqsave(&core->task_queue_lock, flags);
 853                 if (res) {
 854                         list_splice_init(&q, &core->task_queue); /*at head*/
 855                         core->task_queue_size += can_queue;
 856                 }
 857         }
 858         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 859 }
 860
 861 static DECLARE_COMPLETION(queue_th_comp);
 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         struct scsi_core *core = &sas_ha->core;
 871
 872         daemonize("sas_queue_%d", core->shost->host_no);
 873         current->flags |= PF_NOFREEZE;
 874
 875         complete(&queue_th_comp);
 876
 877         while (1) {
 878                 down_interruptible(&core->queue_thread_sema);
 879                 sas_queue(sas_ha);
 880                 if (core->queue_thread_kill)
 881                         break;
 882         }
 883
 884         complete(&queue_th_comp);
 885
 886         return 0;
 887 }
 888
 889 int sas_init_queue(struct sas_ha_struct *sas_ha)
 890 {
 891         int res;
 892         struct scsi_core *core = &sas_ha->core;
 893
 894         spin_lock_init(&core->task_queue_lock);
 895         core->task_queue_size = 0;
 896         INIT_LIST_HEAD(&core->task_queue);
 897         init_MUTEX_LOCKED(&core->queue_thread_sema);
 898
 899         res = kernel_thread(sas_queue_thread, sas_ha, 0);
 900         if (res >= 0)
 901                 wait_for_completion(&queue_th_comp);
 902
 903         return res < 0 ? res : 0;
 904 }
 905
 906 void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
 907 {
 908         unsigned long flags;
 909         struct scsi_core *core = &sas_ha->core;
 910         struct sas_task *task, *n;
 911
 912         init_completion(&queue_th_comp);
 913         core->queue_thread_kill = 1;
 914         up(&core->queue_thread_sema);
 915         wait_for_completion(&queue_th_comp);
 916
 917         if (!list_empty(&core->task_queue))
 918                 SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
 919                             SAS_ADDR(sas_ha->sas_addr));
 920
 921         spin_lock_irqsave(&core->task_queue_lock, flags);
 922         list_for_each_entry_safe(task, n, &core->task_queue, list) {
 923                 struct scsi_cmnd *cmd = task->uldd_task;
 924
 925                 list_del_init(&task->list);
 926
 927                 ASSIGN_SAS_TASK(cmd, NULL);
 928                 sas_free_task(task);
 929                 cmd->result = DID_ABORT << 16;
 930                 cmd->scsi_done(cmd);
 931         }
 932         spin_unlock_irqrestore(&core->task_queue_lock, flags);
 933 }
 934
 935 /*
 936  * Call the LLDD task abort routine directly.  This function is intended for
 937  * use by upper layers that need to tell the LLDD to abort a task.
 938  */
 939 int __sas_task_abort(struct sas_task *task)
 940 {
 941         struct sas_internal *si =
 942                 to_sas_internal(task->dev->port->ha->core.shost->transportt);
 943         unsigned long flags;
 944         int res;
 945
 946         spin_lock_irqsave(&task->task_state_lock, flags);
 947         if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
 948             task->task_state_flags & SAS_TASK_STATE_DONE) {
 949                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 950                 SAS_DPRINTK("%s: Task %p already finished.\n", __FUNCTION__,
 951                             task);
 952                 return 0;
 953         }
 954         task->task_state_flags |= SAS_TASK_STATE_ABORTED;
 955         spin_unlock_irqrestore(&task->task_state_lock, flags);
 956
 957         if (!si->dft->lldd_abort_task)
 958                 return -ENODEV;
 959
 960         res = si->dft->lldd_abort_task(task);
 961
 962         spin_lock_irqsave(&task->task_state_lock, flags);
 963         if ((task->task_state_flags & SAS_TASK_STATE_DONE) ||
 964             (res == TMF_RESP_FUNC_COMPLETE))
 965         {
 966                 spin_unlock_irqrestore(&task->task_state_lock, flags);
 967                 task->task_done(task);
 968                 return 0;
 969         }
 970
 971         if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
 972                 task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
 973         spin_unlock_irqrestore(&task->task_state_lock, flags);
 974
 975         return -EAGAIN;
 976 }
 977
 978 /*
 979  * Tell an upper layer that it needs to initiate an abort for a given task.
 980  * This should only ever be called by an LLDD.
 981  */
 982 void sas_task_abort(struct sas_task *task)
 983 {
 984         struct scsi_cmnd *sc = task->uldd_task;
 985
 986         /* Escape for libsas internal commands */
 987         if (!sc) {
 988                 if (!del_timer(&task->timer))
 989                         return;
 990                 task->timer.function(task->timer.data);
 991                 return;
 992         }
 993
 994         scsi_req_abort_cmd(sc);
 995         scsi_schedule_eh(sc->device->host);
 996 }
 997
 998 EXPORT_SYMBOL_GPL(sas_queuecommand);
 999 EXPORT_SYMBOL_GPL(sas_target_alloc);
1000 EXPORT_SYMBOL_GPL(sas_slave_configure);
1001 EXPORT_SYMBOL_GPL(sas_slave_destroy);
1002 EXPORT_SYMBOL_GPL(sas_change_queue_depth);
1003 EXPORT_SYMBOL_GPL(sas_change_queue_type);
1004 EXPORT_SYMBOL_GPL(sas_bios_param);
1005 EXPORT_SYMBOL_GPL(__sas_task_abort);
1006 EXPORT_SYMBOL_GPL(sas_task_abort);
1007 EXPORT_SYMBOL_GPL(sas_phy_reset);
1008 EXPORT_SYMBOL_GPL(sas_phy_enable);
1009 EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
1010 EXPORT_SYMBOL_GPL(sas_eh_bus_reset_handler);