1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * hosts.c Copyright (C) 1992 Drew Eckhardt 4 * Copyright (C) 1993, 1994, 1995 Eric Youngdale 5 * Copyright (C) 2002-2003 Christoph Hellwig 6 * 7 * mid to lowlevel SCSI driver interface 8 * Initial versions: Drew Eckhardt 9 * Subsequent revisions: Eric Youngdale 10 * 11 * <drew@colorado.edu> 12 * 13 * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli 14 * Added QLOGIC QLA1280 SCSI controller kernel host support. 15 * August 4, 1999 Fred Lewis, Intel DuPont 16 * 17 * Updated to reflect the new initialization scheme for the higher 18 * level of scsi drivers (sd/sr/st) 19 * September 17, 2000 Torben Mathiasen <tmm@image.dk> 20 * 21 * Restructured scsi_host lists and associated functions. 22 * September 04, 2002 Mike Anderson (andmike@us.ibm.com) 23 */ 24 25 #include <linux/module.h> 26 #include <linux/blkdev.h> 27 #include <linux/kernel.h> 28 #include <linux/slab.h> 29 #include <linux/kthread.h> 30 #include <linux/string.h> 31 #include <linux/mm.h> 32 #include <linux/init.h> 33 #include <linux/completion.h> 34 #include <linux/transport_class.h> 35 #include <linux/platform_device.h> 36 #include <linux/pm_runtime.h> 37 #include <linux/idr.h> 38 #include <scsi/scsi_device.h> 39 #include <scsi/scsi_host.h> 40 #include <scsi/scsi_transport.h> 41 #include <scsi/scsi_cmnd.h> 42 43 #include "scsi_priv.h" 44 #include "scsi_logging.h" 45 46 47 static int shost_eh_deadline = -1; 48 49 module_param_named(eh_deadline, shost_eh_deadline, int, S_IRUGO|S_IWUSR); 50 MODULE_PARM_DESC(eh_deadline, 51 "SCSI EH timeout in seconds (should be between 0 and 2^31-1)"); 52 53 static DEFINE_IDA(host_index_ida); 54 55 scsi_host_cls_release(struct device * dev)56 static void scsi_host_cls_release(struct device *dev) 57 { 58 put_device(&class_to_shost(dev)->shost_gendev); 59 } 60 61 static struct class shost_class = { 62 .name = "scsi_host", 63 .dev_release = scsi_host_cls_release, 64 .dev_groups = scsi_shost_groups, 65 }; 66 67 /** 68 * scsi_host_set_state - Take the given host through the host state model. 69 * @shost: scsi host to change the state of. 70 * @state: state to change to. 71 * 72 * Returns zero if unsuccessful or an error if the requested 73 * transition is illegal. 74 **/ scsi_host_set_state(struct Scsi_Host * shost,enum scsi_host_state state)75 int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) 76 { 77 enum scsi_host_state oldstate = shost->shost_state; 78 79 if (state == oldstate) 80 return 0; 81 82 switch (state) { 83 case SHOST_CREATED: 84 /* There are no legal states that come back to 85 * created. This is the manually initialised start 86 * state */ 87 goto illegal; 88 89 case SHOST_RUNNING: 90 switch (oldstate) { 91 case SHOST_CREATED: 92 case SHOST_RECOVERY: 93 break; 94 default: 95 goto illegal; 96 } 97 break; 98 99 case SHOST_RECOVERY: 100 switch (oldstate) { 101 case SHOST_RUNNING: 102 break; 103 default: 104 goto illegal; 105 } 106 break; 107 108 case SHOST_CANCEL: 109 switch (oldstate) { 110 case SHOST_CREATED: 111 case SHOST_RUNNING: 112 case SHOST_CANCEL_RECOVERY: 113 break; 114 default: 115 goto illegal; 116 } 117 break; 118 119 case SHOST_DEL: 120 switch (oldstate) { 121 case SHOST_CANCEL: 122 case SHOST_DEL_RECOVERY: 123 break; 124 default: 125 goto illegal; 126 } 127 break; 128 129 case SHOST_CANCEL_RECOVERY: 130 switch (oldstate) { 131 case SHOST_CANCEL: 132 case SHOST_RECOVERY: 133 break; 134 default: 135 goto illegal; 136 } 137 break; 138 139 case SHOST_DEL_RECOVERY: 140 switch (oldstate) { 141 case SHOST_CANCEL_RECOVERY: 142 break; 143 default: 144 goto illegal; 145 } 146 break; 147 } 148 shost->shost_state = state; 149 return 0; 150 151 illegal: 152 SCSI_LOG_ERROR_RECOVERY(1, 153 shost_printk(KERN_ERR, shost, 154 "Illegal host state transition" 155 "%s->%s\n", 156 scsi_host_state_name(oldstate), 157 scsi_host_state_name(state))); 158 return -EINVAL; 159 } 160 161 /** 162 * scsi_remove_host - remove a scsi host 163 * @shost: a pointer to a scsi host to remove 164 **/ scsi_remove_host(struct Scsi_Host * shost)165 void scsi_remove_host(struct Scsi_Host *shost) 166 { 167 unsigned long flags; 168 169 mutex_lock(&shost->scan_mutex); 170 spin_lock_irqsave(shost->host_lock, flags); 171 if (scsi_host_set_state(shost, SHOST_CANCEL)) 172 if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) { 173 spin_unlock_irqrestore(shost->host_lock, flags); 174 mutex_unlock(&shost->scan_mutex); 175 return; 176 } 177 spin_unlock_irqrestore(shost->host_lock, flags); 178 179 scsi_autopm_get_host(shost); 180 flush_workqueue(shost->tmf_work_q); 181 scsi_forget_host(shost); 182 mutex_unlock(&shost->scan_mutex); 183 scsi_proc_host_rm(shost); 184 scsi_proc_hostdir_rm(shost->hostt); 185 186 /* 187 * New SCSI devices cannot be attached anymore because of the SCSI host 188 * state so drop the tag set refcnt. Wait until the tag set refcnt drops 189 * to zero because .exit_cmd_priv implementations may need the host 190 * pointer. 191 */ 192 kref_put(&shost->tagset_refcnt, scsi_mq_free_tags); 193 wait_for_completion(&shost->tagset_freed); 194 195 spin_lock_irqsave(shost->host_lock, flags); 196 if (scsi_host_set_state(shost, SHOST_DEL)) 197 BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY)); 198 spin_unlock_irqrestore(shost->host_lock, flags); 199 200 transport_unregister_device(&shost->shost_gendev); 201 device_unregister(&shost->shost_dev); 202 device_del(&shost->shost_gendev); 203 } 204 EXPORT_SYMBOL(scsi_remove_host); 205 206 /** 207 * scsi_add_host_with_dma - add a scsi host with dma device 208 * @shost: scsi host pointer to add 209 * @dev: a struct device of type scsi class 210 * @dma_dev: dma device for the host 211 * 212 * Note: You rarely need to worry about this unless you're in a 213 * virtualised host environments, so use the simpler scsi_add_host() 214 * function instead. 215 * 216 * Return value: 217 * 0 on success / != 0 for error 218 **/ scsi_add_host_with_dma(struct Scsi_Host * shost,struct device * dev,struct device * dma_dev)219 int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, 220 struct device *dma_dev) 221 { 222 const struct scsi_host_template *sht = shost->hostt; 223 int error = -EINVAL; 224 225 shost_printk(KERN_INFO, shost, "%s\n", 226 sht->info ? sht->info(shost) : sht->name); 227 228 if (!shost->can_queue) { 229 shost_printk(KERN_ERR, shost, 230 "can_queue = 0 no longer supported\n"); 231 goto fail; 232 } 233 234 /* Use min_t(int, ...) in case shost->can_queue exceeds SHRT_MAX */ 235 shost->cmd_per_lun = min_t(int, shost->cmd_per_lun, 236 shost->can_queue); 237 238 error = scsi_init_sense_cache(shost); 239 if (error) 240 goto fail; 241 242 if (!shost->shost_gendev.parent) 243 shost->shost_gendev.parent = dev ? dev : &platform_bus; 244 if (!dma_dev) 245 dma_dev = shost->shost_gendev.parent; 246 247 shost->dma_dev = dma_dev; 248 249 if (dma_dev->dma_mask) { 250 shost->max_sectors = min_t(unsigned int, shost->max_sectors, 251 dma_max_mapping_size(dma_dev) >> SECTOR_SHIFT); 252 } 253 254 error = scsi_mq_setup_tags(shost); 255 if (error) 256 goto fail; 257 258 kref_init(&shost->tagset_refcnt); 259 init_completion(&shost->tagset_freed); 260 261 /* 262 * Increase usage count temporarily here so that calling 263 * scsi_autopm_put_host() will trigger runtime idle if there is 264 * nothing else preventing suspending the device. 265 */ 266 pm_runtime_get_noresume(&shost->shost_gendev); 267 pm_runtime_set_active(&shost->shost_gendev); 268 pm_runtime_enable(&shost->shost_gendev); 269 device_enable_async_suspend(&shost->shost_gendev); 270 271 error = device_add(&shost->shost_gendev); 272 if (error) 273 goto out_disable_runtime_pm; 274 275 scsi_host_set_state(shost, SHOST_RUNNING); 276 get_device(shost->shost_gendev.parent); 277 278 device_enable_async_suspend(&shost->shost_dev); 279 280 get_device(&shost->shost_gendev); 281 error = device_add(&shost->shost_dev); 282 if (error) 283 goto out_del_gendev; 284 285 if (shost->transportt->host_size) { 286 shost->shost_data = kzalloc(shost->transportt->host_size, 287 GFP_KERNEL); 288 if (shost->shost_data == NULL) { 289 error = -ENOMEM; 290 goto out_del_dev; 291 } 292 } 293 294 if (shost->transportt->create_work_queue) { 295 shost->work_q = alloc_workqueue( 296 "scsi_wq_%d", 297 WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND, 1, 298 shost->host_no); 299 300 if (!shost->work_q) { 301 error = -EINVAL; 302 goto out_del_dev; 303 } 304 } 305 306 error = scsi_sysfs_add_host(shost); 307 if (error) 308 goto out_del_dev; 309 310 scsi_proc_host_add(shost); 311 scsi_autopm_put_host(shost); 312 return error; 313 314 /* 315 * Any host allocation in this function will be freed in 316 * scsi_host_dev_release(). 317 */ 318 out_del_dev: 319 device_del(&shost->shost_dev); 320 out_del_gendev: 321 /* 322 * Host state is SHOST_RUNNING so we have to explicitly release 323 * ->shost_dev. 324 */ 325 put_device(&shost->shost_dev); 326 device_del(&shost->shost_gendev); 327 out_disable_runtime_pm: 328 device_disable_async_suspend(&shost->shost_gendev); 329 pm_runtime_disable(&shost->shost_gendev); 330 pm_runtime_set_suspended(&shost->shost_gendev); 331 pm_runtime_put_noidle(&shost->shost_gendev); 332 kref_put(&shost->tagset_refcnt, scsi_mq_free_tags); 333 fail: 334 return error; 335 } 336 EXPORT_SYMBOL(scsi_add_host_with_dma); 337 scsi_host_dev_release(struct device * dev)338 static void scsi_host_dev_release(struct device *dev) 339 { 340 struct Scsi_Host *shost = dev_to_shost(dev); 341 struct device *parent = dev->parent; 342 343 /* Wait for functions invoked through call_rcu(&scmd->rcu, ...) */ 344 rcu_barrier(); 345 346 if (shost->tmf_work_q) 347 destroy_workqueue(shost->tmf_work_q); 348 if (shost->ehandler) 349 kthread_stop(shost->ehandler); 350 if (shost->work_q) 351 destroy_workqueue(shost->work_q); 352 353 if (shost->shost_state == SHOST_CREATED) { 354 /* 355 * Free the shost_dev device name and remove the proc host dir 356 * here if scsi_host_{alloc,put}() have been called but neither 357 * scsi_host_add() nor scsi_remove_host() has been called. 358 * This avoids that the memory allocated for the shost_dev 359 * name as well as the proc dir structure are leaked. 360 */ 361 scsi_proc_hostdir_rm(shost->hostt); 362 kfree(dev_name(&shost->shost_dev)); 363 } 364 365 kfree(shost->shost_data); 366 367 ida_free(&host_index_ida, shost->host_no); 368 369 if (shost->shost_state != SHOST_CREATED) 370 put_device(parent); 371 kfree(shost); 372 } 373 374 static const struct device_type scsi_host_type = { 375 .name = "scsi_host", 376 .release = scsi_host_dev_release, 377 }; 378 379 /** 380 * scsi_host_alloc - register a scsi host adapter instance. 381 * @sht: pointer to scsi host template 382 * @privsize: extra bytes to allocate for driver 383 * 384 * Note: 385 * Allocate a new Scsi_Host and perform basic initialization. 386 * The host is not published to the scsi midlayer until scsi_add_host 387 * is called. 388 * 389 * Return value: 390 * Pointer to a new Scsi_Host 391 **/ scsi_host_alloc(const struct scsi_host_template * sht,int privsize)392 struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *sht, int privsize) 393 { 394 struct Scsi_Host *shost; 395 int index; 396 397 shost = kzalloc(sizeof(struct Scsi_Host) + privsize, GFP_KERNEL); 398 if (!shost) 399 return NULL; 400 401 shost->host_lock = &shost->default_lock; 402 spin_lock_init(shost->host_lock); 403 shost->shost_state = SHOST_CREATED; 404 INIT_LIST_HEAD(&shost->__devices); 405 INIT_LIST_HEAD(&shost->__targets); 406 INIT_LIST_HEAD(&shost->eh_abort_list); 407 INIT_LIST_HEAD(&shost->eh_cmd_q); 408 INIT_LIST_HEAD(&shost->starved_list); 409 init_waitqueue_head(&shost->host_wait); 410 mutex_init(&shost->scan_mutex); 411 412 index = ida_alloc(&host_index_ida, GFP_KERNEL); 413 if (index < 0) { 414 kfree(shost); 415 return NULL; 416 } 417 shost->host_no = index; 418 419 shost->dma_channel = 0xff; 420 421 /* These three are default values which can be overridden */ 422 shost->max_channel = 0; 423 shost->max_id = 8; 424 shost->max_lun = 8; 425 426 /* Give each shost a default transportt */ 427 shost->transportt = &blank_transport_template; 428 429 /* 430 * All drivers right now should be able to handle 12 byte 431 * commands. Every so often there are requests for 16 byte 432 * commands, but individual low-level drivers need to certify that 433 * they actually do something sensible with such commands. 434 */ 435 shost->max_cmd_len = 12; 436 shost->hostt = sht; 437 shost->this_id = sht->this_id; 438 shost->can_queue = sht->can_queue; 439 shost->sg_tablesize = sht->sg_tablesize; 440 shost->sg_prot_tablesize = sht->sg_prot_tablesize; 441 shost->cmd_per_lun = sht->cmd_per_lun; 442 shost->no_write_same = sht->no_write_same; 443 shost->host_tagset = sht->host_tagset; 444 shost->queuecommand_may_block = sht->queuecommand_may_block; 445 446 if (shost_eh_deadline == -1 || !sht->eh_host_reset_handler) 447 shost->eh_deadline = -1; 448 else if ((ulong) shost_eh_deadline * HZ > INT_MAX) { 449 shost_printk(KERN_WARNING, shost, 450 "eh_deadline %u too large, setting to %u\n", 451 shost_eh_deadline, INT_MAX / HZ); 452 shost->eh_deadline = INT_MAX; 453 } else 454 shost->eh_deadline = shost_eh_deadline * HZ; 455 456 if (sht->supported_mode == MODE_UNKNOWN) 457 /* means we didn't set it ... default to INITIATOR */ 458 shost->active_mode = MODE_INITIATOR; 459 else 460 shost->active_mode = sht->supported_mode; 461 462 if (sht->max_host_blocked) 463 shost->max_host_blocked = sht->max_host_blocked; 464 else 465 shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED; 466 467 /* 468 * If the driver imposes no hard sector transfer limit, start at 469 * machine infinity initially. 470 */ 471 if (sht->max_sectors) 472 shost->max_sectors = sht->max_sectors; 473 else 474 shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS; 475 476 if (sht->max_segment_size) 477 shost->max_segment_size = sht->max_segment_size; 478 else 479 shost->max_segment_size = BLK_MAX_SEGMENT_SIZE; 480 481 /* 32-byte (dword) is a common minimum for HBAs. */ 482 if (sht->dma_alignment) 483 shost->dma_alignment = sht->dma_alignment; 484 else 485 shost->dma_alignment = 3; 486 487 /* 488 * assume a 4GB boundary, if not set 489 */ 490 if (sht->dma_boundary) 491 shost->dma_boundary = sht->dma_boundary; 492 else 493 shost->dma_boundary = 0xffffffff; 494 495 if (sht->virt_boundary_mask) 496 shost->virt_boundary_mask = sht->virt_boundary_mask; 497 498 device_initialize(&shost->shost_gendev); 499 dev_set_name(&shost->shost_gendev, "host%d", shost->host_no); 500 shost->shost_gendev.bus = &scsi_bus_type; 501 shost->shost_gendev.type = &scsi_host_type; 502 scsi_enable_async_suspend(&shost->shost_gendev); 503 504 device_initialize(&shost->shost_dev); 505 shost->shost_dev.parent = &shost->shost_gendev; 506 shost->shost_dev.class = &shost_class; 507 dev_set_name(&shost->shost_dev, "host%d", shost->host_no); 508 shost->shost_dev.groups = sht->shost_groups; 509 510 shost->ehandler = kthread_run(scsi_error_handler, shost, 511 "scsi_eh_%d", shost->host_no); 512 if (IS_ERR(shost->ehandler)) { 513 shost_printk(KERN_WARNING, shost, 514 "error handler thread failed to spawn, error = %ld\n", 515 PTR_ERR(shost->ehandler)); 516 shost->ehandler = NULL; 517 goto fail; 518 } 519 520 shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d", 521 WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 522 1, shost->host_no); 523 if (!shost->tmf_work_q) { 524 shost_printk(KERN_WARNING, shost, 525 "failed to create tmf workq\n"); 526 goto fail; 527 } 528 if (scsi_proc_hostdir_add(shost->hostt) < 0) 529 goto fail; 530 return shost; 531 fail: 532 /* 533 * Host state is still SHOST_CREATED and that is enough to release 534 * ->shost_gendev. scsi_host_dev_release() will free 535 * dev_name(&shost->shost_dev). 536 */ 537 put_device(&shost->shost_gendev); 538 539 return NULL; 540 } 541 EXPORT_SYMBOL(scsi_host_alloc); 542 __scsi_host_match(struct device * dev,const void * data)543 static int __scsi_host_match(struct device *dev, const void *data) 544 { 545 struct Scsi_Host *p; 546 const unsigned int *hostnum = data; 547 548 p = class_to_shost(dev); 549 return p->host_no == *hostnum; 550 } 551 552 /** 553 * scsi_host_lookup - get a reference to a Scsi_Host by host no 554 * @hostnum: host number to locate 555 * 556 * Return value: 557 * A pointer to located Scsi_Host or NULL. 558 * 559 * The caller must do a scsi_host_put() to drop the reference 560 * that scsi_host_get() took. The put_device() below dropped 561 * the reference from class_find_device(). 562 **/ scsi_host_lookup(unsigned int hostnum)563 struct Scsi_Host *scsi_host_lookup(unsigned int hostnum) 564 { 565 struct device *cdev; 566 struct Scsi_Host *shost = NULL; 567 568 cdev = class_find_device(&shost_class, NULL, &hostnum, 569 __scsi_host_match); 570 if (cdev) { 571 shost = scsi_host_get(class_to_shost(cdev)); 572 put_device(cdev); 573 } 574 return shost; 575 } 576 EXPORT_SYMBOL(scsi_host_lookup); 577 578 /** 579 * scsi_host_get - inc a Scsi_Host ref count 580 * @shost: Pointer to Scsi_Host to inc. 581 **/ scsi_host_get(struct Scsi_Host * shost)582 struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost) 583 { 584 if ((shost->shost_state == SHOST_DEL) || 585 !get_device(&shost->shost_gendev)) 586 return NULL; 587 return shost; 588 } 589 EXPORT_SYMBOL(scsi_host_get); 590 scsi_host_check_in_flight(struct request * rq,void * data)591 static bool scsi_host_check_in_flight(struct request *rq, void *data) 592 { 593 int *count = data; 594 struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); 595 596 if (test_bit(SCMD_STATE_INFLIGHT, &cmd->state)) 597 (*count)++; 598 599 return true; 600 } 601 602 /** 603 * scsi_host_busy - Return the host busy counter 604 * @shost: Pointer to Scsi_Host to inc. 605 **/ scsi_host_busy(struct Scsi_Host * shost)606 int scsi_host_busy(struct Scsi_Host *shost) 607 { 608 int cnt = 0; 609 610 blk_mq_tagset_busy_iter(&shost->tag_set, 611 scsi_host_check_in_flight, &cnt); 612 return cnt; 613 } 614 EXPORT_SYMBOL(scsi_host_busy); 615 616 /** 617 * scsi_host_put - dec a Scsi_Host ref count 618 * @shost: Pointer to Scsi_Host to dec. 619 **/ scsi_host_put(struct Scsi_Host * shost)620 void scsi_host_put(struct Scsi_Host *shost) 621 { 622 put_device(&shost->shost_gendev); 623 } 624 EXPORT_SYMBOL(scsi_host_put); 625 scsi_init_hosts(void)626 int scsi_init_hosts(void) 627 { 628 return class_register(&shost_class); 629 } 630 scsi_exit_hosts(void)631 void scsi_exit_hosts(void) 632 { 633 class_unregister(&shost_class); 634 ida_destroy(&host_index_ida); 635 } 636 scsi_is_host_device(const struct device * dev)637 int scsi_is_host_device(const struct device *dev) 638 { 639 return dev->type == &scsi_host_type; 640 } 641 EXPORT_SYMBOL(scsi_is_host_device); 642 643 /** 644 * scsi_queue_work - Queue work to the Scsi_Host workqueue. 645 * @shost: Pointer to Scsi_Host. 646 * @work: Work to queue for execution. 647 * 648 * Return value: 649 * 1 - work queued for execution 650 * 0 - work is already queued 651 * -EINVAL - work queue doesn't exist 652 **/ scsi_queue_work(struct Scsi_Host * shost,struct work_struct * work)653 int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work) 654 { 655 if (unlikely(!shost->work_q)) { 656 shost_printk(KERN_ERR, shost, 657 "ERROR: Scsi host '%s' attempted to queue scsi-work, " 658 "when no workqueue created.\n", shost->hostt->name); 659 dump_stack(); 660 661 return -EINVAL; 662 } 663 664 return queue_work(shost->work_q, work); 665 } 666 EXPORT_SYMBOL_GPL(scsi_queue_work); 667 668 /** 669 * scsi_flush_work - Flush a Scsi_Host's workqueue. 670 * @shost: Pointer to Scsi_Host. 671 **/ scsi_flush_work(struct Scsi_Host * shost)672 void scsi_flush_work(struct Scsi_Host *shost) 673 { 674 if (!shost->work_q) { 675 shost_printk(KERN_ERR, shost, 676 "ERROR: Scsi host '%s' attempted to flush scsi-work, " 677 "when no workqueue created.\n", shost->hostt->name); 678 dump_stack(); 679 return; 680 } 681 682 flush_workqueue(shost->work_q); 683 } 684 EXPORT_SYMBOL_GPL(scsi_flush_work); 685 complete_all_cmds_iter(struct request * rq,void * data)686 static bool complete_all_cmds_iter(struct request *rq, void *data) 687 { 688 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq); 689 enum scsi_host_status status = *(enum scsi_host_status *)data; 690 691 scsi_dma_unmap(scmd); 692 scmd->result = 0; 693 set_host_byte(scmd, status); 694 scsi_done(scmd); 695 return true; 696 } 697 698 /** 699 * scsi_host_complete_all_commands - Terminate all running commands 700 * @shost: Scsi Host on which commands should be terminated 701 * @status: Status to be set for the terminated commands 702 * 703 * There is no protection against modification of the number 704 * of outstanding commands. It is the responsibility of the 705 * caller to ensure that concurrent I/O submission and/or 706 * completion is stopped when calling this function. 707 */ scsi_host_complete_all_commands(struct Scsi_Host * shost,enum scsi_host_status status)708 void scsi_host_complete_all_commands(struct Scsi_Host *shost, 709 enum scsi_host_status status) 710 { 711 blk_mq_tagset_busy_iter(&shost->tag_set, complete_all_cmds_iter, 712 &status); 713 } 714 EXPORT_SYMBOL_GPL(scsi_host_complete_all_commands); 715 716 struct scsi_host_busy_iter_data { 717 bool (*fn)(struct scsi_cmnd *, void *); 718 void *priv; 719 }; 720 __scsi_host_busy_iter_fn(struct request * req,void * priv)721 static bool __scsi_host_busy_iter_fn(struct request *req, void *priv) 722 { 723 struct scsi_host_busy_iter_data *iter_data = priv; 724 struct scsi_cmnd *sc = blk_mq_rq_to_pdu(req); 725 726 return iter_data->fn(sc, iter_data->priv); 727 } 728 729 /** 730 * scsi_host_busy_iter - Iterate over all busy commands 731 * @shost: Pointer to Scsi_Host. 732 * @fn: Function to call on each busy command 733 * @priv: Data pointer passed to @fn 734 * 735 * If locking against concurrent command completions is required 736 * ithas to be provided by the caller 737 **/ scsi_host_busy_iter(struct Scsi_Host * shost,bool (* fn)(struct scsi_cmnd *,void *),void * priv)738 void scsi_host_busy_iter(struct Scsi_Host *shost, 739 bool (*fn)(struct scsi_cmnd *, void *), 740 void *priv) 741 { 742 struct scsi_host_busy_iter_data iter_data = { 743 .fn = fn, 744 .priv = priv, 745 }; 746 747 blk_mq_tagset_busy_iter(&shost->tag_set, __scsi_host_busy_iter_fn, 748 &iter_data); 749 } 750 EXPORT_SYMBOL_GPL(scsi_host_busy_iter); 751