drivers/scsi/isci/request.h

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  * redistributing this file, you may do so under either license.
   4  *
   5  * GPL LICENSE SUMMARY
   6  *
   7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  21  * The full GNU General Public License is included in this distribution
  22  * in the file called LICENSE.GPL.
  23  *
  24  * BSD LICENSE
  25  *
  26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  *
  33  *   * Redistributions of source code must retain the above copyright
  34  *     notice, this list of conditions and the following disclaimer.
  35  *   * Redistributions in binary form must reproduce the above copyright
  36  *     notice, this list of conditions and the following disclaimer in
  37  *     the documentation and/or other materials provided with the
  38  *     distribution.
  39  *   * Neither the name of Intel Corporation nor the names of its
  40  *     contributors may be used to endorse or promote products derived
  41  *     from this software without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  54  */
  55
  56 #ifndef _ISCI_REQUEST_H_
  57 #define _ISCI_REQUEST_H_
  58
  59 #include "isci.h"
  60 #include "host.h"
  61 #include "scu_task_context.h"
  62 #include "stp_request.h"
  63
  64 /**
  65  * struct isci_request_status - This enum defines the possible states of an I/O
  66  *    request.
  67  *
  68  *
  69  */
  70 enum isci_request_status {
  71         unallocated = 0x00,
  72         allocated   = 0x01,
  73         started     = 0x02,
  74         completed   = 0x03,
  75         aborting    = 0x04,
  76         aborted     = 0x05,
  77         terminating = 0x06,
  78         dead        = 0x07
  79 };
  80
  81 enum task_type {
  82         io_task  = 0,
  83         tmf_task = 1
  84 };
  85
  86 enum sci_request_protocol {
  87         SCIC_NO_PROTOCOL,
  88         SCIC_SMP_PROTOCOL,
  89         SCIC_SSP_PROTOCOL,
  90         SCIC_STP_PROTOCOL
  91 }; /* XXX remove me, use sas_task.{dev|task_proto} instead */;
  92
  93 struct scic_sds_request {
  94         /**
  95          * This field contains the information for the base request state machine.
  96          */
  97         struct sci_base_state_machine state_machine;
  98
  99         /**
 100          * This field simply points to the controller to which this IO request
 101          * is associated.
 102          */
 103         struct scic_sds_controller *owning_controller;
 104
 105         /**
 106          * This field simply points to the remote device to which this IO request
 107          * is associated.
 108          */
 109         struct scic_sds_remote_device *target_device;
 110
 111         /**
 112          * This field is utilized to determine if the SCI user is managing
 113          * the IO tag for this request or if the core is managing it.
 114          */
 115         bool was_tag_assigned_by_user;
 116
 117         /**
 118          * This field indicates the IO tag for this request.  The IO tag is
 119          * comprised of the task_index and a sequence count. The sequence count
 120          * is utilized to help identify tasks from one life to another.
 121          */
 122         u16 io_tag;
 123
 124         /**
 125          * This field specifies the protocol being utilized for this
 126          * IO request.
 127          */
 128         enum sci_request_protocol protocol;
 129
 130         /**
 131          * This field indicates the completion status taken from the SCUs
 132          * completion code.  It indicates the completion result for the SCU hardware.
 133          */
 134         u32 scu_status;
 135
 136         /**
 137          * This field indicates the completion status returned to the SCI user.  It
 138          * indicates the users view of the io request completion.
 139          */
 140         u32 sci_status;
 141
 142         /**
 143          * This field contains the value to be utilized when posting (e.g. Post_TC,
 144          * Post_TC_Abort) this request to the silicon.
 145          */
 146         u32 post_context;
 147
 148         struct scu_task_context *task_context_buffer;
 149         struct scu_task_context tc ____cacheline_aligned;
 150
 151         /* could be larger with sg chaining */
 152         #define SCU_SGL_SIZE ((SCU_IO_REQUEST_SGE_COUNT + 1) / 2)
 153         struct scu_sgl_element_pair sg_table[SCU_SGL_SIZE] __attribute__ ((aligned(32)));
 154
 155         /**
 156          * This field indicates if this request is a task management request or
 157          * normal IO request.
 158          */
 159         bool is_task_management_request;
 160
 161         /**
 162          * This field indicates that this request contains an initialized started
 163          * substate machine.
 164          */
 165         bool has_started_substate_machine;
 166
 167         /**
 168          * This field is a pointer to the stored rx frame data.  It is used in STP
 169          * internal requests and SMP response frames.  If this field is non-NULL the
 170          * saved frame must be released on IO request completion.
 171          *
 172          * @todo In the future do we want to keep a list of RX frame buffers?
 173          */
 174         u32 saved_rx_frame_index;
 175
 176         /**
 177          * This field specifies the data necessary to manage the sub-state
 178          * machine executed while in the SCI_BASE_REQUEST_STATE_STARTED state.
 179          */
 180         struct sci_base_state_machine started_substate_machine;
 181
 182         /**
 183          * This field specifies the current state handlers in place for this
 184          * IO Request object.  This field is updated each time the request
 185          * changes state.
 186          */
 187         const struct scic_sds_io_request_state_handler *state_handlers;
 188
 189         /**
 190          * This field in the recorded device sequence for the io request.  This is
 191          * recorded during the build operation and is compared in the start
 192          * operation.  If the sequence is different then there was a change of
 193          * devices from the build to start operations.
 194          */
 195         u8 device_sequence;
 196
 197         union {
 198                 struct {
 199                         union {
 200                                 struct ssp_cmd_iu cmd;
 201                                 struct ssp_task_iu tmf;
 202                         };
 203                         union {
 204                                 struct ssp_response_iu rsp;
 205                                 u8 rsp_buf[SSP_RESP_IU_MAX_SIZE];
 206                         };
 207                 } ssp;
 208
 209                 struct {
 210                         struct smp_req cmd;
 211                         struct smp_resp rsp;
 212                 } smp;
 213
 214                 struct {
 215                         struct scic_sds_stp_request req;
 216                         struct host_to_dev_fis cmd;
 217                         struct dev_to_host_fis rsp;
 218                 } stp;
 219         };
 220
 221 };
 222
 223 static inline struct scic_sds_request *to_sci_req(struct scic_sds_stp_request *stp_req)
 224 {
 225         struct scic_sds_request *sci_req;
 226
 227         sci_req = container_of(stp_req, typeof(*sci_req), stp.req);
 228         return sci_req;
 229 }
 230
 231 struct isci_request {
 232         enum isci_request_status status;
 233         enum task_type ttype;
 234         unsigned short io_tag;
 235         bool complete_in_target;
 236         bool terminated;
 237
 238         union ttype_ptr_union {
 239                 struct sas_task *io_task_ptr;   /* When ttype==io_task  */
 240                 struct isci_tmf *tmf_task_ptr;  /* When ttype==tmf_task */
 241         } ttype_ptr;
 242         struct isci_host *isci_host;
 243         struct isci_remote_device *isci_device;
 244         /* For use in the requests_to_{complete|abort} lists: */
 245         struct list_head completed_node;
 246         /* For use in the reqs_in_process list: */
 247         struct list_head dev_node;
 248         spinlock_t state_lock;
 249         dma_addr_t request_daddr;
 250         dma_addr_t zero_scatter_daddr;
 251
 252         unsigned int num_sg_entries;                    /* returned by pci_alloc_sg */
 253
 254         /** Note: "io_request_completion" is completed in two different ways
 255          * depending on whether this is a TMF or regular request.
 256          * - TMF requests are completed in the thread that started them;
 257          * - regular requests are completed in the request completion callback
 258          *   function.
 259          * This difference in operation allows the aborter of a TMF request
 260          * to be sure that once the TMF request completes, the I/O that the
 261          * TMF was aborting is guaranteed to have completed.
 262          */
 263         struct completion *io_request_completion;
 264         struct scic_sds_request sci;
 265 };
 266
 267 static inline struct isci_request *sci_req_to_ireq(struct scic_sds_request *sci_req)
 268 {
 269         struct isci_request *ireq = container_of(sci_req, typeof(*ireq), sci);
 270
 271         return ireq;
 272 }
 273
 274 /**
 275  * enum sci_base_request_states - This enumeration depicts all the states for
 276  *    the common request state machine.
 277  *
 278  *
 279  */
 280 enum sci_base_request_states {
 281         /**
 282          * Simply the initial state for the base request state machine.
 283          */
 284         SCI_BASE_REQUEST_STATE_INITIAL,
 285
 286         /**
 287          * This state indicates that the request has been constructed. This state
 288          * is entered from the INITIAL state.
 289          */
 290         SCI_BASE_REQUEST_STATE_CONSTRUCTED,
 291
 292         /**
 293          * This state indicates that the request has been started. This state is
 294          * entered from the CONSTRUCTED state.
 295          */
 296         SCI_BASE_REQUEST_STATE_STARTED,
 297
 298         /**
 299          * The AWAIT_TC_COMPLETION sub-state indicates that the started raw
 300          * task management request is waiting for the transmission of the
 301          * initial frame (i.e. command, task, etc.).
 302          */
 303         SCIC_SDS_IO_REQUEST_STARTED_TASK_MGMT_SUBSTATE_AWAIT_TC_COMPLETION,
 304
 305         /**
 306          * This sub-state indicates that the started task management request
 307          * is waiting for the reception of an unsolicited frame
 308          * (i.e. response IU).
 309          */
 310         SCIC_SDS_IO_REQUEST_STARTED_TASK_MGMT_SUBSTATE_AWAIT_TC_RESPONSE,
 311
 312         /**
 313          * This sub-state indicates that the started task management request
 314          * is waiting for the reception of an unsolicited frame
 315          * (i.e. response IU).
 316          */
 317         SCIC_SDS_SMP_REQUEST_STARTED_SUBSTATE_AWAIT_RESPONSE,
 318
 319         /**
 320          * The AWAIT_TC_COMPLETION sub-state indicates that the started SMP request is
 321          * waiting for the transmission of the initial frame (i.e. command, task, etc.).
 322          */
 323         SCIC_SDS_SMP_REQUEST_STARTED_SUBSTATE_AWAIT_TC_COMPLETION,
 324
 325         /**
 326          * This state indicates that the request has completed.
 327          * This state is entered from the STARTED state. This state is entered from
 328          * the ABORTING state.
 329          */
 330         SCI_BASE_REQUEST_STATE_COMPLETED,
 331
 332         /**
 333          * This state indicates that the request is in the process of being
 334          * terminated/aborted.
 335          * This state is entered from the CONSTRUCTED state.
 336          * This state is entered from the STARTED state.
 337          */
 338         SCI_BASE_REQUEST_STATE_ABORTING,
 339
 340         /**
 341          * Simply the final state for the base request state machine.
 342          */
 343         SCI_BASE_REQUEST_STATE_FINAL,
 344 };
 345
 346 typedef enum sci_status (*scic_sds_io_request_handler_t)
 347                                 (struct scic_sds_request *request);
 348 typedef enum sci_status (*scic_sds_io_request_frame_handler_t)
 349                                 (struct scic_sds_request *req, u32 frame);
 350 typedef enum sci_status (*scic_sds_io_request_event_handler_t)
 351                                 (struct scic_sds_request *req, u32 event);
 352 typedef enum sci_status (*scic_sds_io_request_task_completion_handler_t)
 353                                 (struct scic_sds_request *req, u32 completion_code);
 354
 355 /**
 356  * struct scic_sds_io_request_state_handler - This is the SDS core definition
 357  *    of the state handlers.
 358  *
 359  *
 360  */
 361 struct scic_sds_io_request_state_handler {
 362         /**
 363          * The start_handler specifies the method invoked when a user attempts to
 364          * start a request.
 365          */
 366         scic_sds_io_request_handler_t start_handler;
 367
 368         /**
 369          * The abort_handler specifies the method invoked when a user attempts to
 370          * abort a request.
 371          */
 372         scic_sds_io_request_handler_t abort_handler;
 373
 374         /**
 375          * The complete_handler specifies the method invoked when a user attempts to
 376          * complete a request.
 377          */
 378         scic_sds_io_request_handler_t complete_handler;
 379
 380         scic_sds_io_request_task_completion_handler_t tc_completion_handler;
 381         scic_sds_io_request_event_handler_t event_handler;
 382         scic_sds_io_request_frame_handler_t frame_handler;
 383
 384 };
 385
 386 extern const struct sci_base_state scic_sds_io_request_started_task_mgmt_substate_table[];
 387
 388 /**
 389  * scic_sds_request_get_controller() -
 390  *
 391  * This macro will return the controller for this io request object
 392  */
 393 #define scic_sds_request_get_controller(sci_req) \
 394         ((sci_req)->owning_controller)
 395
 396 /**
 397  * scic_sds_request_get_device() -
 398  *
 399  * This macro will return the device for this io request object
 400  */
 401 #define scic_sds_request_get_device(sci_req) \
 402         ((sci_req)->target_device)
 403
 404 /**
 405  * scic_sds_request_get_port() -
 406  *
 407  * This macro will return the port for this io request object
 408  */
 409 #define scic_sds_request_get_port(sci_req)      \
 410         scic_sds_remote_device_get_port(scic_sds_request_get_device(sci_req))
 411
 412 /**
 413  * scic_sds_request_get_post_context() -
 414  *
 415  * This macro returns the constructed post context result for the io request.
 416  */
 417 #define scic_sds_request_get_post_context(sci_req)      \
 418         ((sci_req)->post_context)
 419
 420 /**
 421  * scic_sds_request_get_task_context() -
 422  *
 423  * This is a helper macro to return the os handle for this request object.
 424  */
 425 #define scic_sds_request_get_task_context(request) \
 426         ((request)->task_context_buffer)
 427
 428 /**
 429  * scic_sds_request_set_status() -
 430  *
 431  * This macro will set the scu hardware status and sci request completion
 432  * status for an io request.
 433  */
 434 #define scic_sds_request_set_status(request, scu_status_code, sci_status_code) \
 435         { \
 436                 (request)->scu_status = (scu_status_code); \
 437                 (request)->sci_status = (sci_status_code); \
 438         }
 439
 440 #define scic_sds_request_complete(a_request) \
 441         ((a_request)->state_handlers->complete_handler(a_request))
 442
 443
 444 extern enum sci_status
 445 scic_sds_io_request_tc_completion(struct scic_sds_request *request, u32 completion_code);
 446
 447 /**
 448  * SCU_SGL_ZERO() -
 449  *
 450  * This macro zeros the hardware SGL element data
 451  */
 452 #define SCU_SGL_ZERO(scu_sge) \
 453         { \
 454                 (scu_sge).length = 0; \
 455                 (scu_sge).address_lower = 0; \
 456                 (scu_sge).address_upper = 0; \
 457                 (scu_sge).address_modifier = 0; \
 458         }
 459
 460 /**
 461  * SCU_SGL_COPY() -
 462  *
 463  * This macro copys the SGL Element data from the host os to the hardware SGL
 464  * elment data
 465  */
 466 #define SCU_SGL_COPY(scu_sge, os_sge) \
 467         { \
 468                 (scu_sge).length = sg_dma_len(sg); \
 469                 (scu_sge).address_upper = \
 470                         upper_32_bits(sg_dma_address(sg)); \
 471                 (scu_sge).address_lower = \
 472                         lower_32_bits(sg_dma_address(sg)); \
 473                 (scu_sge).address_modifier = 0; \
 474         }
 475
 476 void scic_sds_request_build_sgl(struct scic_sds_request *sci_req);
 477 enum sci_status scic_sds_request_start(struct scic_sds_request *sci_req);
 478 enum sci_status scic_sds_io_request_terminate(struct scic_sds_request *sci_req);
 479 enum sci_status scic_sds_io_request_event_handler(struct scic_sds_request *sci_req,
 480                                                   u32 event_code);
 481 enum sci_status scic_sds_io_request_frame_handler(struct scic_sds_request *sci_req,
 482                                                   u32 frame_index);
 483 enum sci_status scic_sds_task_request_terminate(struct scic_sds_request *sci_req);
 484 enum sci_status scic_sds_request_started_state_abort_handler(struct scic_sds_request *sci_req);
 485
 486
 487 /* XXX open code in caller */
 488 static inline void *scic_request_get_virt_addr(struct scic_sds_request *sci_req,
 489                                                dma_addr_t phys_addr)
 490 {
 491         struct isci_request *ireq = sci_req_to_ireq(sci_req);
 492         dma_addr_t offset;
 493
 494         BUG_ON(phys_addr < ireq->request_daddr);
 495
 496         offset = phys_addr - ireq->request_daddr;
 497
 498         BUG_ON(offset >= sizeof(*ireq));
 499
 500         return (char *)ireq + offset;
 501 }
 502
 503 /* XXX open code in caller */
 504 static inline dma_addr_t scic_io_request_get_dma_addr(struct scic_sds_request *sci_req,
 505                                                       void *virt_addr)
 506 {
 507         struct isci_request *ireq = sci_req_to_ireq(sci_req);
 508
 509         char *requested_addr = (char *)virt_addr;
 510         char *base_addr = (char *)ireq;
 511
 512         BUG_ON(requested_addr < base_addr);
 513         BUG_ON((requested_addr - base_addr) >= sizeof(*ireq));
 514
 515         return ireq->request_daddr + (requested_addr - base_addr);
 516 }
 517
 518 /**
 519  * This function gets the status of the request object.
 520  * @request: This parameter points to the isci_request object
 521  *
 522  * status of the object as a isci_request_status enum.
 523  */
 524 static inline
 525 enum isci_request_status isci_request_get_state(
 526         struct isci_request *isci_request)
 527 {
 528         BUG_ON(isci_request == NULL);
 529
 530         /*probably a bad sign...        */
 531         if (isci_request->status == unallocated)
 532                 dev_warn(&isci_request->isci_host->pdev->dev,
 533                          "%s: isci_request->status == unallocated\n",
 534                          __func__);
 535
 536         return isci_request->status;
 537 }
 538
 539
 540 /**
 541  * isci_request_change_state() - This function sets the status of the request
 542  *    object.
 543  * @request: This parameter points to the isci_request object
 544  * @status: This Parameter is the new status of the object
 545  *
 546  */
 547 static inline enum isci_request_status isci_request_change_state(
 548         struct isci_request *isci_request,
 549         enum isci_request_status status)
 550 {
 551         enum isci_request_status old_state;
 552         unsigned long flags;
 553
 554         dev_dbg(&isci_request->isci_host->pdev->dev,
 555                 "%s: isci_request = %p, state = 0x%x\n",
 556                 __func__,
 557                 isci_request,
 558                 status);
 559
 560         BUG_ON(isci_request == NULL);
 561
 562         spin_lock_irqsave(&isci_request->state_lock, flags);
 563         old_state = isci_request->status;
 564         isci_request->status = status;
 565         spin_unlock_irqrestore(&isci_request->state_lock, flags);
 566
 567         return old_state;
 568 }
 569
 570 /**
 571  * isci_request_change_started_to_newstate() - This function sets the status of
 572  *    the request object.
 573  * @request: This parameter points to the isci_request object
 574  * @status: This Parameter is the new status of the object
 575  *
 576  * state previous to any change.
 577  */
 578 static inline enum isci_request_status isci_request_change_started_to_newstate(
 579         struct isci_request *isci_request,
 580         struct completion *completion_ptr,
 581         enum isci_request_status newstate)
 582 {
 583         enum isci_request_status old_state;
 584         unsigned long flags;
 585
 586         spin_lock_irqsave(&isci_request->state_lock, flags);
 587
 588         old_state = isci_request->status;
 589
 590         if (old_state == started || old_state == aborting) {
 591                 BUG_ON(isci_request->io_request_completion != NULL);
 592
 593                 isci_request->io_request_completion = completion_ptr;
 594                 isci_request->status = newstate;
 595         }
 596         spin_unlock_irqrestore(&isci_request->state_lock, flags);
 597
 598         dev_dbg(&isci_request->isci_host->pdev->dev,
 599                 "%s: isci_request = %p, old_state = 0x%x\n",
 600                 __func__,
 601                 isci_request,
 602                 old_state);
 603
 604         return old_state;
 605 }
 606
 607 /**
 608  * isci_request_change_started_to_aborted() - This function sets the status of
 609  *    the request object.
 610  * @request: This parameter points to the isci_request object
 611  * @completion_ptr: This parameter is saved as the kernel completion structure
 612  *    signalled when the old request completes.
 613  *
 614  * state previous to any change.
 615  */
 616 static inline enum isci_request_status isci_request_change_started_to_aborted(
 617         struct isci_request *isci_request,
 618         struct completion *completion_ptr)
 619 {
 620         return isci_request_change_started_to_newstate(
 621                        isci_request, completion_ptr, aborted
 622                        );
 623 }
 624 /**
 625  * isci_request_free() - This function frees the request object.
 626  * @isci_host: This parameter specifies the ISCI host object
 627  * @isci_request: This parameter points to the isci_request object
 628  *
 629  */
 630 static inline void isci_request_free(
 631         struct isci_host *isci_host,
 632         struct isci_request *isci_request)
 633 {
 634         if (!isci_request)
 635                 return;
 636
 637         /* release the dma memory if we fail. */
 638         dma_pool_free(isci_host->dma_pool, isci_request,
 639                       isci_request->request_daddr);
 640 }
 641
 642
 643 /* #define ISCI_REQUEST_VALIDATE_ACCESS
 644  */
 645
 646 #ifdef ISCI_REQUEST_VALIDATE_ACCESS
 647
 648 static inline
 649 struct sas_task *isci_request_access_task(struct isci_request *isci_request)
 650 {
 651         BUG_ON(isci_request->ttype != io_task);
 652         return isci_request->ttype_ptr.io_task_ptr;
 653 }
 654
 655 static inline
 656 struct isci_tmf *isci_request_access_tmf(struct isci_request *isci_request)
 657 {
 658         BUG_ON(isci_request->ttype != tmf_task);
 659         return isci_request->ttype_ptr.tmf_task_ptr;
 660 }
 661
 662 #else  /* not ISCI_REQUEST_VALIDATE_ACCESS */
 663
 664 #define isci_request_access_task(RequestPtr) \
 665         ((RequestPtr)->ttype_ptr.io_task_ptr)
 666
 667 #define isci_request_access_tmf(RequestPtr)  \
 668         ((RequestPtr)->ttype_ptr.tmf_task_ptr)
 669
 670 #endif /* not ISCI_REQUEST_VALIDATE_ACCESS */
 671
 672
 673 int isci_request_alloc_tmf(
 674         struct isci_host *isci_host,
 675         struct isci_tmf *isci_tmf,
 676         struct isci_request **isci_request,
 677         struct isci_remote_device *isci_device,
 678         gfp_t gfp_flags);
 679
 680
 681 int isci_request_execute(
 682         struct isci_host *isci_host,
 683         struct sas_task *task,
 684         struct isci_request **request,
 685         gfp_t gfp_flags);
 686
 687 /**
 688  * isci_request_unmap_sgl() - This function unmaps the DMA address of a given
 689  *    sgl
 690  * @request: This parameter points to the isci_request object
 691  * @*pdev: This Parameter is the pci_device struct for the controller
 692  *
 693  */
 694 static inline void isci_request_unmap_sgl(
 695         struct isci_request *request,
 696         struct pci_dev *pdev)
 697 {
 698         struct sas_task *task = isci_request_access_task(request);
 699
 700         dev_dbg(&request->isci_host->pdev->dev,
 701                 "%s: request = %p, task = %p,\n"
 702                 "task->data_dir = %d, is_sata = %d\n ",
 703                 __func__,
 704                 request,
 705                 task,
 706                 task->data_dir,
 707                 sas_protocol_ata(task->task_proto));
 708
 709         if ((task->data_dir != PCI_DMA_NONE) &&
 710             !sas_protocol_ata(task->task_proto)) {
 711                 if (task->num_scatter == 0)
 712                         /* 0 indicates a single dma address */
 713                         dma_unmap_single(
 714                                 &pdev->dev,
 715                                 request->zero_scatter_daddr,
 716                                 task->total_xfer_len,
 717                                 task->data_dir
 718                                 );
 719
 720                 else  /* unmap the sgl dma addresses */
 721                         dma_unmap_sg(
 722                                 &pdev->dev,
 723                                 task->scatter,
 724                                 request->num_sg_entries,
 725                                 task->data_dir
 726                                 );
 727         }
 728 }
 729
 730 /**
 731  * isci_request_io_request_get_next_sge() - This function is called by the sci
 732  *    core to retrieve the next sge for a given request.
 733  * @request: This parameter is the isci_request object.
 734  * @current_sge_address: This parameter is the last sge retrieved by the sci
 735  *    core for this request.
 736  *
 737  * pointer to the next sge for specified request.
 738  */
 739 static inline void *isci_request_io_request_get_next_sge(
 740         struct isci_request *request,
 741         void *current_sge_address)
 742 {
 743         struct sas_task *task = isci_request_access_task(request);
 744         void *ret = NULL;
 745
 746         dev_dbg(&request->isci_host->pdev->dev,
 747                 "%s: request = %p, "
 748                 "current_sge_address = %p, "
 749                 "num_scatter = %d\n",
 750                 __func__,
 751                 request,
 752                 current_sge_address,
 753                 task->num_scatter);
 754
 755         if (!current_sge_address)       /* First time through.. */
 756                 ret = task->scatter;    /* always task->scatter */
 757         else if (task->num_scatter == 0) /* Next element, if num_scatter == 0 */
 758                 ret = NULL;              /* there is only one element. */
 759         else
 760                 ret = sg_next(current_sge_address);     /* sg_next returns NULL
 761                                                          * for the last element
 762                                                          */
 763
 764         dev_dbg(&request->isci_host->pdev->dev,
 765                 "%s: next sge address = %p\n",
 766                 __func__,
 767                 ret);
 768
 769         return ret;
 770 }
 771
 772 void isci_terminate_pending_requests(struct isci_host *isci_host,
 773                                      struct isci_remote_device *isci_device,
 774                                      enum isci_request_status new_request_state);
 775 enum sci_status scic_task_request_construct(struct scic_sds_controller *scic,
 776                                             struct scic_sds_remote_device *sci_dev,
 777                                             u16 io_tag,
 778                                             struct scic_sds_request *sci_req);
 779 enum sci_status scic_task_request_construct_ssp(struct scic_sds_request *sci_req);
 780 enum sci_status scic_task_request_construct_sata(struct scic_sds_request *sci_req);
 781 void scic_stp_io_request_set_ncq_tag(struct scic_sds_request *sci_req, u16 ncq_tag);
 782 void scic_sds_smp_request_copy_response(struct scic_sds_request *sci_req);
 783 #endif /* !defined(_ISCI_REQUEST_H_) */