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 = sas_init_events(sas_ha); 127 if (error) { 128 pr_notice("couldn't start event thread:%d\n", error); 129 goto Undo_ports; 130 } 131 132 error = -ENOMEM; 133 snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev)); 134 sas_ha->event_q = create_singlethread_workqueue(name); 135 if (!sas_ha->event_q) 136 goto Undo_ports; 137 138 snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev)); 139 sas_ha->disco_q = create_singlethread_workqueue(name); 140 if (!sas_ha->disco_q) 141 goto Undo_event_q; 142 143 INIT_LIST_HEAD(&sas_ha->eh_done_q); 144 INIT_LIST_HEAD(&sas_ha->eh_ata_q); 145 146 return 0; 147 148 Undo_event_q: 149 destroy_workqueue(sas_ha->event_q); 150 Undo_ports: 151 sas_unregister_ports(sas_ha); 152 Undo_phys: 153 154 return error; 155 } 156 157 static void sas_disable_events(struct sas_ha_struct *sas_ha) 158 { 159 /* Set the state to unregistered to avoid further unchained 160 * events to be queued, and flush any in-progress drainers 161 */ 162 mutex_lock(&sas_ha->drain_mutex); 163 spin_lock_irq(&sas_ha->lock); 164 clear_bit(SAS_HA_REGISTERED, &sas_ha->state); 165 spin_unlock_irq(&sas_ha->lock); 166 __sas_drain_work(sas_ha); 167 mutex_unlock(&sas_ha->drain_mutex); 168 } 169 170 int sas_unregister_ha(struct sas_ha_struct *sas_ha) 171 { 172 sas_disable_events(sas_ha); 173 sas_unregister_ports(sas_ha); 174 175 /* flush unregistration work */ 176 mutex_lock(&sas_ha->drain_mutex); 177 __sas_drain_work(sas_ha); 178 mutex_unlock(&sas_ha->drain_mutex); 179 180 destroy_workqueue(sas_ha->disco_q); 181 destroy_workqueue(sas_ha->event_q); 182 183 return 0; 184 } 185 186 static int sas_get_linkerrors(struct sas_phy *phy) 187 { 188 if (scsi_is_sas_phy_local(phy)) { 189 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 190 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 191 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 192 struct sas_internal *i = 193 to_sas_internal(sas_ha->core.shost->transportt); 194 195 return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL); 196 } 197 198 return sas_smp_get_phy_events(phy); 199 } 200 201 int sas_try_ata_reset(struct asd_sas_phy *asd_phy) 202 { 203 struct domain_device *dev = NULL; 204 205 /* try to route user requested link resets through libata */ 206 if (asd_phy->port) 207 dev = asd_phy->port->port_dev; 208 209 /* validate that dev has been probed */ 210 if (dev) 211 dev = sas_find_dev_by_rphy(dev->rphy); 212 213 if (dev && dev_is_sata(dev)) { 214 sas_ata_schedule_reset(dev); 215 sas_ata_wait_eh(dev); 216 return 0; 217 } 218 219 return -ENODEV; 220 } 221 222 /* 223 * transport_sas_phy_reset - reset a phy and permit libata to manage the link 224 * 225 * phy reset request via sysfs in host workqueue context so we know we 226 * can block on eh and safely traverse the domain_device topology 227 */ 228 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset) 229 { 230 enum phy_func reset_type; 231 232 if (hard_reset) 233 reset_type = PHY_FUNC_HARD_RESET; 234 else 235 reset_type = PHY_FUNC_LINK_RESET; 236 237 if (scsi_is_sas_phy_local(phy)) { 238 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 239 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 240 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 241 struct sas_internal *i = 242 to_sas_internal(sas_ha->core.shost->transportt); 243 244 if (!hard_reset && sas_try_ata_reset(asd_phy) == 0) 245 return 0; 246 return i->dft->lldd_control_phy(asd_phy, reset_type, NULL); 247 } else { 248 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 249 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 250 struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number); 251 252 if (ata_dev && !hard_reset) { 253 sas_ata_schedule_reset(ata_dev); 254 sas_ata_wait_eh(ata_dev); 255 return 0; 256 } else 257 return sas_smp_phy_control(ddev, phy->number, reset_type, NULL); 258 } 259 } 260 261 static int sas_phy_enable(struct sas_phy *phy, int enable) 262 { 263 int ret; 264 enum phy_func cmd; 265 266 if (enable) 267 cmd = PHY_FUNC_LINK_RESET; 268 else 269 cmd = PHY_FUNC_DISABLE; 270 271 if (scsi_is_sas_phy_local(phy)) { 272 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 273 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 274 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 275 struct sas_internal *i = 276 to_sas_internal(sas_ha->core.shost->transportt); 277 278 if (enable) 279 ret = transport_sas_phy_reset(phy, 0); 280 else 281 ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL); 282 } else { 283 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 284 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 285 286 if (enable) 287 ret = transport_sas_phy_reset(phy, 0); 288 else 289 ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL); 290 } 291 return ret; 292 } 293 294 int sas_phy_reset(struct sas_phy *phy, int hard_reset) 295 { 296 int ret; 297 enum phy_func reset_type; 298 299 if (!phy->enabled) 300 return -ENODEV; 301 302 if (hard_reset) 303 reset_type = PHY_FUNC_HARD_RESET; 304 else 305 reset_type = PHY_FUNC_LINK_RESET; 306 307 if (scsi_is_sas_phy_local(phy)) { 308 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 309 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 310 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 311 struct sas_internal *i = 312 to_sas_internal(sas_ha->core.shost->transportt); 313 314 ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL); 315 } else { 316 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 317 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 318 ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL); 319 } 320 return ret; 321 } 322 323 int sas_set_phy_speed(struct sas_phy *phy, 324 struct sas_phy_linkrates *rates) 325 { 326 int ret; 327 328 if ((rates->minimum_linkrate && 329 rates->minimum_linkrate > phy->maximum_linkrate) || 330 (rates->maximum_linkrate && 331 rates->maximum_linkrate < phy->minimum_linkrate)) 332 return -EINVAL; 333 334 if (rates->minimum_linkrate && 335 rates->minimum_linkrate < phy->minimum_linkrate_hw) 336 rates->minimum_linkrate = phy->minimum_linkrate_hw; 337 338 if (rates->maximum_linkrate && 339 rates->maximum_linkrate > phy->maximum_linkrate_hw) 340 rates->maximum_linkrate = phy->maximum_linkrate_hw; 341 342 if (scsi_is_sas_phy_local(phy)) { 343 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 344 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 345 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 346 struct sas_internal *i = 347 to_sas_internal(sas_ha->core.shost->transportt); 348 349 ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE, 350 rates); 351 } else { 352 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 353 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 354 ret = sas_smp_phy_control(ddev, phy->number, 355 PHY_FUNC_LINK_RESET, rates); 356 357 } 358 359 return ret; 360 } 361 362 void sas_prep_resume_ha(struct sas_ha_struct *ha) 363 { 364 int i; 365 366 set_bit(SAS_HA_REGISTERED, &ha->state); 367 368 /* clear out any stale link events/data from the suspension path */ 369 for (i = 0; i < ha->num_phys; i++) { 370 struct asd_sas_phy *phy = ha->sas_phy[i]; 371 372 memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE); 373 phy->frame_rcvd_size = 0; 374 } 375 } 376 EXPORT_SYMBOL(sas_prep_resume_ha); 377 378 static int phys_suspended(struct sas_ha_struct *ha) 379 { 380 int i, rc = 0; 381 382 for (i = 0; i < ha->num_phys; i++) { 383 struct asd_sas_phy *phy = ha->sas_phy[i]; 384 385 if (phy->suspended) 386 rc++; 387 } 388 389 return rc; 390 } 391 392 void sas_resume_ha(struct sas_ha_struct *ha) 393 { 394 const unsigned long tmo = msecs_to_jiffies(25000); 395 int i; 396 397 /* deform ports on phys that did not resume 398 * at this point we may be racing the phy coming back (as posted 399 * by the lldd). So we post the event and once we are in the 400 * libsas context check that the phy remains suspended before 401 * tearing it down. 402 */ 403 i = phys_suspended(ha); 404 if (i) 405 dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n", 406 i, i > 1 ? "s" : ""); 407 wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo); 408 for (i = 0; i < ha->num_phys; i++) { 409 struct asd_sas_phy *phy = ha->sas_phy[i]; 410 411 if (phy->suspended) { 412 dev_warn(&phy->phy->dev, "resume timeout\n"); 413 sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT); 414 } 415 } 416 417 /* all phys are back up or timed out, turn on i/o so we can 418 * flush out disks that did not return 419 */ 420 scsi_unblock_requests(ha->core.shost); 421 sas_drain_work(ha); 422 } 423 EXPORT_SYMBOL(sas_resume_ha); 424 425 void sas_suspend_ha(struct sas_ha_struct *ha) 426 { 427 int i; 428 429 sas_disable_events(ha); 430 scsi_block_requests(ha->core.shost); 431 for (i = 0; i < ha->num_phys; i++) { 432 struct asd_sas_port *port = ha->sas_port[i]; 433 434 sas_discover_event(port, DISCE_SUSPEND); 435 } 436 437 /* flush suspend events while unregistered */ 438 mutex_lock(&ha->drain_mutex); 439 __sas_drain_work(ha); 440 mutex_unlock(&ha->drain_mutex); 441 } 442 EXPORT_SYMBOL(sas_suspend_ha); 443 444 static void sas_phy_release(struct sas_phy *phy) 445 { 446 kfree(phy->hostdata); 447 phy->hostdata = NULL; 448 } 449 450 static void phy_reset_work(struct work_struct *work) 451 { 452 struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work); 453 454 d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset); 455 } 456 457 static void phy_enable_work(struct work_struct *work) 458 { 459 struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work); 460 461 d->enable_result = sas_phy_enable(d->phy, d->enable); 462 } 463 464 static int sas_phy_setup(struct sas_phy *phy) 465 { 466 struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL); 467 468 if (!d) 469 return -ENOMEM; 470 471 mutex_init(&d->event_lock); 472 INIT_SAS_WORK(&d->reset_work, phy_reset_work); 473 INIT_SAS_WORK(&d->enable_work, phy_enable_work); 474 d->phy = phy; 475 phy->hostdata = d; 476 477 return 0; 478 } 479 480 static int queue_phy_reset(struct sas_phy *phy, int hard_reset) 481 { 482 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 483 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost); 484 struct sas_phy_data *d = phy->hostdata; 485 int rc; 486 487 if (!d) 488 return -ENOMEM; 489 490 /* libsas workqueue coordinates ata-eh reset with discovery */ 491 mutex_lock(&d->event_lock); 492 d->reset_result = 0; 493 d->hard_reset = hard_reset; 494 495 spin_lock_irq(&ha->lock); 496 sas_queue_work(ha, &d->reset_work); 497 spin_unlock_irq(&ha->lock); 498 499 rc = sas_drain_work(ha); 500 if (rc == 0) 501 rc = d->reset_result; 502 mutex_unlock(&d->event_lock); 503 504 return rc; 505 } 506 507 static int queue_phy_enable(struct sas_phy *phy, int enable) 508 { 509 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 510 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost); 511 struct sas_phy_data *d = phy->hostdata; 512 int rc; 513 514 if (!d) 515 return -ENOMEM; 516 517 /* libsas workqueue coordinates ata-eh reset with discovery */ 518 mutex_lock(&d->event_lock); 519 d->enable_result = 0; 520 d->enable = enable; 521 522 spin_lock_irq(&ha->lock); 523 sas_queue_work(ha, &d->enable_work); 524 spin_unlock_irq(&ha->lock); 525 526 rc = sas_drain_work(ha); 527 if (rc == 0) 528 rc = d->enable_result; 529 mutex_unlock(&d->event_lock); 530 531 return rc; 532 } 533 534 static struct sas_function_template sft = { 535 .phy_enable = queue_phy_enable, 536 .phy_reset = queue_phy_reset, 537 .phy_setup = sas_phy_setup, 538 .phy_release = sas_phy_release, 539 .set_phy_speed = sas_set_phy_speed, 540 .get_linkerrors = sas_get_linkerrors, 541 .smp_handler = sas_smp_handler, 542 }; 543 544 static inline ssize_t phy_event_threshold_show(struct device *dev, 545 struct device_attribute *attr, char *buf) 546 { 547 struct Scsi_Host *shost = class_to_shost(dev); 548 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost); 549 550 return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres); 551 } 552 553 static inline ssize_t phy_event_threshold_store(struct device *dev, 554 struct device_attribute *attr, 555 const char *buf, size_t count) 556 { 557 struct Scsi_Host *shost = class_to_shost(dev); 558 struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost); 559 560 sha->event_thres = simple_strtol(buf, NULL, 10); 561 562 /* threshold cannot be set too small */ 563 if (sha->event_thres < 32) 564 sha->event_thres = 32; 565 566 return count; 567 } 568 569 DEVICE_ATTR(phy_event_threshold, 570 S_IRUGO|S_IWUSR, 571 phy_event_threshold_show, 572 phy_event_threshold_store); 573 EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold); 574 575 struct scsi_transport_template * 576 sas_domain_attach_transport(struct sas_domain_function_template *dft) 577 { 578 struct scsi_transport_template *stt = sas_attach_transport(&sft); 579 struct sas_internal *i; 580 581 if (!stt) 582 return stt; 583 584 i = to_sas_internal(stt); 585 i->dft = dft; 586 stt->create_work_queue = 1; 587 stt->eh_strategy_handler = sas_scsi_recover_host; 588 589 return stt; 590 } 591 EXPORT_SYMBOL_GPL(sas_domain_attach_transport); 592 593 594 struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy) 595 { 596 struct asd_sas_event *event; 597 gfp_t flags = in_interrupt() ? GFP_ATOMIC : GFP_KERNEL; 598 struct sas_ha_struct *sas_ha = phy->ha; 599 struct sas_internal *i = 600 to_sas_internal(sas_ha->core.shost->transportt); 601 602 event = kmem_cache_zalloc(sas_event_cache, flags); 603 if (!event) 604 return NULL; 605 606 atomic_inc(&phy->event_nr); 607 608 if (atomic_read(&phy->event_nr) > phy->ha->event_thres) { 609 if (i->dft->lldd_control_phy) { 610 if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) { 611 pr_notice("The phy%d bursting events, shut it down.\n", 612 phy->id); 613 sas_notify_phy_event(phy, PHYE_SHUTDOWN); 614 } 615 } else { 616 /* Do not support PHY control, stop allocating events */ 617 WARN_ONCE(1, "PHY control not supported.\n"); 618 kmem_cache_free(sas_event_cache, event); 619 atomic_dec(&phy->event_nr); 620 event = NULL; 621 } 622 } 623 624 return event; 625 } 626 627 void sas_free_event(struct asd_sas_event *event) 628 { 629 struct asd_sas_phy *phy = event->phy; 630 631 kmem_cache_free(sas_event_cache, event); 632 atomic_dec(&phy->event_nr); 633 } 634 635 /* ---------- SAS Class register/unregister ---------- */ 636 637 static int __init sas_class_init(void) 638 { 639 sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN); 640 if (!sas_task_cache) 641 goto out; 642 643 sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN); 644 if (!sas_event_cache) 645 goto free_task_kmem; 646 647 return 0; 648 free_task_kmem: 649 kmem_cache_destroy(sas_task_cache); 650 out: 651 return -ENOMEM; 652 } 653 654 static void __exit sas_class_exit(void) 655 { 656 kmem_cache_destroy(sas_task_cache); 657 kmem_cache_destroy(sas_event_cache); 658 } 659 660 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>"); 661 MODULE_DESCRIPTION("SAS Transport Layer"); 662 MODULE_LICENSE("GPL v2"); 663 664 module_init(sas_class_init); 665 module_exit(sas_class_exit); 666 667 EXPORT_SYMBOL_GPL(sas_register_ha); 668 EXPORT_SYMBOL_GPL(sas_unregister_ha); 669