1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Serial Attached SCSI (SAS) Transport Layer initialization 4 * 5 * Copyright (C) 2005 Adaptec, Inc. All rights reserved. 6 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/slab.h> 11 #include <linux/init.h> 12 #include <linux/device.h> 13 #include <linux/spinlock.h> 14 #include <scsi/sas_ata.h> 15 #include <scsi/scsi_host.h> 16 #include <scsi/scsi_device.h> 17 #include <scsi/scsi_transport.h> 18 #include <scsi/scsi_transport_sas.h> 19 20 #include "sas_internal.h" 21 22 #include "scsi_sas_internal.h" 23 24 static struct kmem_cache *sas_task_cache; 25 static struct kmem_cache *sas_event_cache; 26 27 struct sas_task *sas_alloc_task(gfp_t flags) 28 { 29 struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags); 30 31 if (task) { 32 spin_lock_init(&task->task_state_lock); 33 task->task_state_flags = SAS_TASK_STATE_PENDING; 34 } 35 36 return task; 37 } 38 EXPORT_SYMBOL_GPL(sas_alloc_task); 39 40 struct sas_task *sas_alloc_slow_task(gfp_t flags) 41 { 42 struct sas_task *task = sas_alloc_task(flags); 43 struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags); 44 45 if (!task || !slow) { 46 if (task) 47 kmem_cache_free(sas_task_cache, task); 48 kfree(slow); 49 return NULL; 50 } 51 52 task->slow_task = slow; 53 slow->task = task; 54 timer_setup(&slow->timer, NULL, 0); 55 init_completion(&slow->completion); 56 57 return task; 58 } 59 EXPORT_SYMBOL_GPL(sas_alloc_slow_task); 60 61 void sas_free_task(struct sas_task *task) 62 { 63 if (task) { 64 kfree(task->slow_task); 65 kmem_cache_free(sas_task_cache, task); 66 } 67 } 68 EXPORT_SYMBOL_GPL(sas_free_task); 69 70 /*------------ SAS addr hash -----------*/ 71 void sas_hash_addr(u8 *hashed, const u8 *sas_addr) 72 { 73 const u32 poly = 0x00DB2777; 74 u32 r = 0; 75 int i; 76 77 for (i = 0; i < SAS_ADDR_SIZE; i++) { 78 int b; 79 80 for (b = (SAS_ADDR_SIZE - 1); b >= 0; b--) { 81 r <<= 1; 82 if ((1 << b) & sas_addr[i]) { 83 if (!(r & 0x01000000)) 84 r ^= poly; 85 } else if (r & 0x01000000) { 86 r ^= poly; 87 } 88 } 89 } 90 91 hashed[0] = (r >> 16) & 0xFF; 92 hashed[1] = (r >> 8) & 0xFF; 93 hashed[2] = r & 0xFF; 94 } 95 96 int sas_register_ha(struct sas_ha_struct *sas_ha) 97 { 98 char name[64]; 99 int error = 0; 100 101 mutex_init(&sas_ha->disco_mutex); 102 spin_lock_init(&sas_ha->phy_port_lock); 103 sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr); 104 105 set_bit(SAS_HA_REGISTERED, &sas_ha->state); 106 spin_lock_init(&sas_ha->lock); 107 mutex_init(&sas_ha->drain_mutex); 108 init_waitqueue_head(&sas_ha->eh_wait_q); 109 INIT_LIST_HEAD(&sas_ha->defer_q); 110 INIT_LIST_HEAD(&sas_ha->eh_dev_q); 111 112 sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES; 113 114 error = sas_register_phys(sas_ha); 115 if (error) { 116 pr_notice("couldn't register sas phys:%d\n", error); 117 return error; 118 } 119 120 error = sas_register_ports(sas_ha); 121 if (error) { 122 pr_notice("couldn't register sas ports:%d\n", error); 123 goto Undo_phys; 124 } 125 126 error = -ENOMEM; 127 snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev)); 128 sas_ha->event_q = create_singlethread_workqueue(name); 129 if (!sas_ha->event_q) 130 goto Undo_ports; 131 132 snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev)); 133 sas_ha->disco_q = create_singlethread_workqueue(name); 134 if (!sas_ha->disco_q) 135 goto Undo_event_q; 136 137 INIT_LIST_HEAD(&sas_ha->eh_done_q); 138 INIT_LIST_HEAD(&sas_ha->eh_ata_q); 139 140 return 0; 141 142 Undo_event_q: 143 destroy_workqueue(sas_ha->event_q); 144 Undo_ports: 145 sas_unregister_ports(sas_ha); 146 Undo_phys: 147 148 return error; 149 } 150 EXPORT_SYMBOL_GPL(sas_register_ha); 151 152 static void sas_disable_events(struct sas_ha_struct *sas_ha) 153 { 154 /* Set the state to unregistered to avoid further unchained 155 * events to be queued, and flush any in-progress drainers 156 */ 157 mutex_lock(&sas_ha->drain_mutex); 158 spin_lock_irq(&sas_ha->lock); 159 clear_bit(SAS_HA_REGISTERED, &sas_ha->state); 160 spin_unlock_irq(&sas_ha->lock); 161 __sas_drain_work(sas_ha); 162 mutex_unlock(&sas_ha->drain_mutex); 163 } 164 165 int sas_unregister_ha(struct sas_ha_struct *sas_ha) 166 { 167 sas_disable_events(sas_ha); 168 sas_unregister_ports(sas_ha); 169 170 /* flush unregistration work */ 171 mutex_lock(&sas_ha->drain_mutex); 172 __sas_drain_work(sas_ha); 173 mutex_unlock(&sas_ha->drain_mutex); 174 175 destroy_workqueue(sas_ha->disco_q); 176 destroy_workqueue(sas_ha->event_q); 177 178 return 0; 179 } 180 EXPORT_SYMBOL_GPL(sas_unregister_ha); 181 182 static int sas_get_linkerrors(struct sas_phy *phy) 183 { 184 if (scsi_is_sas_phy_local(phy)) { 185 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 186 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 187 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 188 struct sas_internal *i = 189 to_sas_internal(sas_ha->core.shost->transportt); 190 191 return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL); 192 } 193 194 return sas_smp_get_phy_events(phy); 195 } 196 197 int sas_try_ata_reset(struct asd_sas_phy *asd_phy) 198 { 199 struct domain_device *dev = NULL; 200 201 /* try to route user requested link resets through libata */ 202 if (asd_phy->port) 203 dev = asd_phy->port->port_dev; 204 205 /* validate that dev has been probed */ 206 if (dev) 207 dev = sas_find_dev_by_rphy(dev->rphy); 208 209 if (dev && dev_is_sata(dev)) { 210 sas_ata_schedule_reset(dev); 211 sas_ata_wait_eh(dev); 212 return 0; 213 } 214 215 return -ENODEV; 216 } 217 218 /* 219 * transport_sas_phy_reset - reset a phy and permit libata to manage the link 220 * 221 * phy reset request via sysfs in host workqueue context so we know we 222 * can block on eh and safely traverse the domain_device topology 223 */ 224 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset) 225 { 226 enum phy_func reset_type; 227 228 if (hard_reset) 229 reset_type = PHY_FUNC_HARD_RESET; 230 else 231 reset_type = PHY_FUNC_LINK_RESET; 232 233 if (scsi_is_sas_phy_local(phy)) { 234 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 235 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 236 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 237 struct sas_internal *i = 238 to_sas_internal(sas_ha->core.shost->transportt); 239 240 if (!hard_reset && sas_try_ata_reset(asd_phy) == 0) 241 return 0; 242 return i->dft->lldd_control_phy(asd_phy, reset_type, NULL); 243 } else { 244 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 245 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 246 struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number); 247 248 if (ata_dev && !hard_reset) { 249 sas_ata_schedule_reset(ata_dev); 250 sas_ata_wait_eh(ata_dev); 251 return 0; 252 } else 253 return sas_smp_phy_control(ddev, phy->number, reset_type, NULL); 254 } 255 } 256 257 int sas_phy_enable(struct sas_phy *phy, int enable) 258 { 259 int ret; 260 enum phy_func cmd; 261 262 if (enable) 263 cmd = PHY_FUNC_LINK_RESET; 264 else 265 cmd = PHY_FUNC_DISABLE; 266 267 if (scsi_is_sas_phy_local(phy)) { 268 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 269 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 270 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 271 struct sas_internal *i = 272 to_sas_internal(sas_ha->core.shost->transportt); 273 274 if (enable) 275 ret = transport_sas_phy_reset(phy, 0); 276 else 277 ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL); 278 } else { 279 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 280 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 281 282 if (enable) 283 ret = transport_sas_phy_reset(phy, 0); 284 else 285 ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL); 286 } 287 return ret; 288 } 289 EXPORT_SYMBOL_GPL(sas_phy_enable); 290 291 int sas_phy_reset(struct sas_phy *phy, int hard_reset) 292 { 293 int ret; 294 enum phy_func reset_type; 295 296 if (!phy->enabled) 297 return -ENODEV; 298 299 if (hard_reset) 300 reset_type = PHY_FUNC_HARD_RESET; 301 else 302 reset_type = PHY_FUNC_LINK_RESET; 303 304 if (scsi_is_sas_phy_local(phy)) { 305 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 306 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 307 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 308 struct sas_internal *i = 309 to_sas_internal(sas_ha->core.shost->transportt); 310 311 ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL); 312 } else { 313 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 314 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 315 ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL); 316 } 317 return ret; 318 } 319 EXPORT_SYMBOL_GPL(sas_phy_reset); 320 321 int sas_set_phy_speed(struct sas_phy *phy, 322 struct sas_phy_linkrates *rates) 323 { 324 int ret; 325 326 if ((rates->minimum_linkrate && 327 rates->minimum_linkrate > phy->maximum_linkrate) || 328 (rates->maximum_linkrate && 329 rates->maximum_linkrate < phy->minimum_linkrate)) 330 return -EINVAL; 331 332 if (rates->minimum_linkrate && 333 rates->minimum_linkrate < phy->minimum_linkrate_hw) 334 rates->minimum_linkrate = phy->minimum_linkrate_hw; 335 336 if (rates->maximum_linkrate && 337 rates->maximum_linkrate > phy->maximum_linkrate_hw) 338 rates->maximum_linkrate = phy->maximum_linkrate_hw; 339 340 if (scsi_is_sas_phy_local(phy)) { 341 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 342 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 343 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 344 struct sas_internal *i = 345 to_sas_internal(sas_ha->core.shost->transportt); 346 347 ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE, 348 rates); 349 } else { 350 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 351 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 352 ret = sas_smp_phy_control(ddev, phy->number, 353 PHY_FUNC_LINK_RESET, rates); 354 355 } 356 357 return ret; 358 } 359 360 void sas_prep_resume_ha(struct sas_ha_struct *ha) 361 { 362 int i; 363 364 set_bit(SAS_HA_REGISTERED, &ha->state); 365 366 /* clear out any stale link events/data from the suspension path */ 367 for (i = 0; i < ha->num_phys; i++) { 368 struct asd_sas_phy *phy = ha->sas_phy[i]; 369 370 memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE); 371 phy->frame_rcvd_size = 0; 372 } 373 } 374 EXPORT_SYMBOL(sas_prep_resume_ha); 375 376 static int phys_suspended(struct sas_ha_struct *ha) 377 { 378 int i, rc = 0; 379 380 for (i = 0; i < ha->num_phys; i++) { 381 struct asd_sas_phy *phy = ha->sas_phy[i]; 382 383 if (phy->suspended) 384 rc++; 385 } 386 387 return rc; 388 } 389 390 void sas_resume_ha(struct sas_ha_struct *ha) 391 { 392 const unsigned long tmo = msecs_to_jiffies(25000); 393 int i; 394 395 /* deform ports on phys that did not resume 396 * at this point we may be racing the phy coming back (as posted 397 * by the lldd). So we post the event and once we are in the 398 * libsas context check that the phy remains suspended before 399 * tearing it down. 400 */ 401 i = phys_suspended(ha); 402 if (i) 403 dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n", 404 i, i > 1 ? "s" : ""); 405 wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo); 406 for (i = 0; i < ha->num_phys; i++) { 407 struct asd_sas_phy *phy = ha->sas_phy[i]; 408 409 if (phy->suspended) { 410 dev_warn(&phy->phy->dev, "resume timeout\n"); 411 sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT, 412 GFP_KERNEL); 413 } 414 } 415 416 /* all phys are back up or timed out, turn on i/o so we can 417 * flush out disks that did not return 418 */ 419 scsi_unblock_requests(ha->core.shost); 420 sas_drain_work(ha); 421 } 422 EXPORT_SYMBOL(sas_resume_ha); 423 424 void sas_suspend_ha(struct sas_ha_struct *ha) 425 { 426 int i; 427 428 sas_disable_events(ha); 429 scsi_block_requests(ha->core.shost); 430 for (i = 0; i < ha->num_phys; i++) { 431 struct asd_sas_port *port = ha->sas_port[i]; 432 433 sas_discover_event(port, DISCE_SUSPEND); 434 } 435 436 /* flush suspend events while unregistered */ 437 mutex_lock(&ha->drain_mutex); 438 __sas_drain_work(ha); 439 mutex_unlock(&ha->drain_mutex); 440 } 441 EXPORT_SYMBOL(sas_suspend_ha); 442 443 static void sas_phy_release(struct sas_phy *phy) 444 { 445 kfree(phy->hostdata); 446 phy->hostdata = NULL; 447 } 448 449 static void phy_reset_work(struct work_struct *work) 450 { 451 struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work); 452 453 d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset); 454 } 455 456 static void phy_enable_work(struct work_struct *work) 457 { 458 struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work); 459 460 d->enable_result = sas_phy_enable(d->phy, d->enable); 461 } 462 463 static int sas_phy_setup(struct sas_phy *phy) 464 { 465 struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL); 466 467 if (!d) 468 return -ENOMEM; 469 470 mutex_init(&d->event_lock); 471 INIT_SAS_WORK(&d->reset_work, phy_reset_work); 472 INIT_SAS_WORK(&d->enable_work, phy_enable_work); 473 d->phy = phy; 474 phy->hostdata = d; 475 476 return 0; 477 } 478 479 static int queue_phy_reset(struct sas_phy *phy, int hard_reset) 480 { 481 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 482 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost); 483 struct sas_phy_data *d = phy->hostdata; 484 int rc; 485 486 if (!d) 487 return -ENOMEM; 488 489 /* libsas workqueue coordinates ata-eh reset with discovery */ 490 mutex_lock(&d->event_lock); 491 d->reset_result = 0; 492 d->hard_reset = hard_reset; 493 494 spin_lock_irq(&ha->lock); 495 sas_queue_work(ha, &d->reset_work); 496 spin_unlock_irq(&ha->lock); 497 498 rc = sas_drain_work(ha); 499 if (rc == 0) 500 rc = d->reset_result; 501 mutex_unlock(&d->event_lock); 502 503 return rc; 504 } 505 506 static int queue_phy_enable(struct sas_phy *phy, int enable) 507 { 508 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 509 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost); 510 struct sas_phy_data *d = phy->hostdata; 511 int rc; 512 513 if (!d) 514 return -ENOMEM; 515 516 /* libsas workqueue coordinates ata-eh reset with discovery */ 517 mutex_lock(&d->event_lock); 518 d->enable_result = 0; 519 d->enable = enable; 520 521 spin_lock_irq(&ha->lock); 522 sas_queue_work(ha, &d->enable_work); 523 spin_unlock_irq(&ha->lock); 524 525 rc = sas_drain_work(ha); 526 if (rc == 0) 527 rc = d->enable_result; 528 mutex_unlock(&d->event_lock); 529 530 return rc; 531 } 532 533 static struct sas_function_template sft = { 534 .phy_enable = queue_phy_enable, 535 .phy_reset = queue_phy_reset, 536 .phy_setup = sas_phy_setup, 537 .phy_release = sas_phy_release, 538 .set_phy_speed = sas_set_phy_speed, 539 .get_linkerrors = sas_get_linkerrors, 540 .smp_handler = sas_smp_handler, 541 }; 542 543 static inline ssize_t phy_event_threshold_show(struct device *dev, 544 struct device_attribute *attr, char *buf) 545 { 546 struct Scsi_Host *shost = class_to_shost(dev); 547 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost); 548 549 return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres); 550 } 551 552 static inline ssize_t phy_event_threshold_store(struct device *dev, 553 struct device_attribute *attr, 554 const char *buf, size_t count) 555 { 556 struct Scsi_Host *shost = class_to_shost(dev); 557 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost); 558 559 sha->event_thres = simple_strtol(buf, NULL, 10); 560 561 /* threshold cannot be set too small */ 562 if (sha->event_thres < 32) 563 sha->event_thres = 32; 564 565 return count; 566 } 567 568 DEVICE_ATTR(phy_event_threshold, 569 S_IRUGO|S_IWUSR, 570 phy_event_threshold_show, 571 phy_event_threshold_store); 572 EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold); 573 574 struct scsi_transport_template * 575 sas_domain_attach_transport(struct sas_domain_function_template *dft) 576 { 577 struct scsi_transport_template *stt = sas_attach_transport(&sft); 578 struct sas_internal *i; 579 580 if (!stt) 581 return stt; 582 583 i = to_sas_internal(stt); 584 i->dft = dft; 585 stt->create_work_queue = 1; 586 stt->eh_strategy_handler = sas_scsi_recover_host; 587 588 return stt; 589 } 590 EXPORT_SYMBOL_GPL(sas_domain_attach_transport); 591 592 struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy, 593 gfp_t gfp_flags) 594 { 595 struct asd_sas_event *event; 596 struct sas_ha_struct *sas_ha = phy->ha; 597 struct sas_internal *i = 598 to_sas_internal(sas_ha->core.shost->transportt); 599 600 event = kmem_cache_zalloc(sas_event_cache, gfp_flags); 601 if (!event) 602 return NULL; 603 604 atomic_inc(&phy->event_nr); 605 606 if (atomic_read(&phy->event_nr) > phy->ha->event_thres) { 607 if (i->dft->lldd_control_phy) { 608 if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) { 609 pr_notice("The phy%d bursting events, shut it down.\n", 610 phy->id); 611 sas_notify_phy_event(phy, PHYE_SHUTDOWN, 612 gfp_flags); 613 } 614 } else { 615 /* Do not support PHY control, stop allocating events */ 616 WARN_ONCE(1, "PHY control not supported.\n"); 617 kmem_cache_free(sas_event_cache, event); 618 atomic_dec(&phy->event_nr); 619 event = NULL; 620 } 621 } 622 623 return event; 624 } 625 626 void sas_free_event(struct asd_sas_event *event) 627 { 628 struct asd_sas_phy *phy = event->phy; 629 630 kmem_cache_free(sas_event_cache, event); 631 atomic_dec(&phy->event_nr); 632 } 633 634 /* ---------- SAS Class register/unregister ---------- */ 635 636 static int __init sas_class_init(void) 637 { 638 sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN); 639 if (!sas_task_cache) 640 goto out; 641 642 sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN); 643 if (!sas_event_cache) 644 goto free_task_kmem; 645 646 return 0; 647 free_task_kmem: 648 kmem_cache_destroy(sas_task_cache); 649 out: 650 return -ENOMEM; 651 } 652 653 static void __exit sas_class_exit(void) 654 { 655 kmem_cache_destroy(sas_task_cache); 656 kmem_cache_destroy(sas_event_cache); 657 } 658 659 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>"); 660 MODULE_DESCRIPTION("SAS Transport Layer"); 661 MODULE_LICENSE("GPL v2"); 662 663 module_init(sas_class_init); 664 module_exit(sas_class_exit); 665 666