1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Serial Attached SCSI (SAS) Discover process 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/scatterlist.h> 10 #include <linux/slab.h> 11 #include <scsi/scsi_host.h> 12 #include <scsi/scsi_eh.h> 13 #include "sas_internal.h" 14 15 #include <scsi/scsi_transport.h> 16 #include <scsi/scsi_transport_sas.h> 17 #include <scsi/sas_ata.h> 18 #include "scsi_sas_internal.h" 19 20 /* ---------- Basic task processing for discovery purposes ---------- */ 21 22 void sas_init_dev(struct domain_device *dev) 23 { 24 switch (dev->dev_type) { 25 case SAS_END_DEVICE: 26 INIT_LIST_HEAD(&dev->ssp_dev.eh_list_node); 27 break; 28 case SAS_EDGE_EXPANDER_DEVICE: 29 case SAS_FANOUT_EXPANDER_DEVICE: 30 INIT_LIST_HEAD(&dev->ex_dev.children); 31 mutex_init(&dev->ex_dev.cmd_mutex); 32 break; 33 default: 34 break; 35 } 36 } 37 38 /* ---------- Domain device discovery ---------- */ 39 40 /** 41 * sas_get_port_device - Discover devices which caused port creation 42 * @port: pointer to struct sas_port of interest 43 * 44 * Devices directly attached to a HA port, have no parent. This is 45 * how we know they are (domain) "root" devices. All other devices 46 * do, and should have their "parent" pointer set appropriately as 47 * soon as a child device is discovered. 48 */ 49 static int sas_get_port_device(struct asd_sas_port *port) 50 { 51 struct asd_sas_phy *phy; 52 struct sas_rphy *rphy; 53 struct domain_device *dev; 54 int rc = -ENODEV; 55 56 dev = sas_alloc_device(); 57 if (!dev) 58 return -ENOMEM; 59 60 spin_lock_irq(&port->phy_list_lock); 61 if (list_empty(&port->phy_list)) { 62 spin_unlock_irq(&port->phy_list_lock); 63 sas_put_device(dev); 64 return -ENODEV; 65 } 66 phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el); 67 spin_lock(&phy->frame_rcvd_lock); 68 memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd), 69 (size_t)phy->frame_rcvd_size)); 70 spin_unlock(&phy->frame_rcvd_lock); 71 spin_unlock_irq(&port->phy_list_lock); 72 73 if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) { 74 struct dev_to_host_fis *fis = 75 (struct dev_to_host_fis *) dev->frame_rcvd; 76 if (fis->interrupt_reason == 1 && fis->lbal == 1 && 77 fis->byte_count_low == 0x69 && fis->byte_count_high == 0x96 78 && (fis->device & ~0x10) == 0) 79 dev->dev_type = SAS_SATA_PM; 80 else 81 dev->dev_type = SAS_SATA_DEV; 82 dev->tproto = SAS_PROTOCOL_SATA; 83 } else if (port->oob_mode == SAS_OOB_MODE) { 84 struct sas_identify_frame *id = 85 (struct sas_identify_frame *) dev->frame_rcvd; 86 dev->dev_type = id->dev_type; 87 dev->iproto = id->initiator_bits; 88 dev->tproto = id->target_bits; 89 } else { 90 /* If the oob mode is OOB_NOT_CONNECTED, the port is 91 * disconnected due to race with PHY down. We cannot 92 * continue to discover this port 93 */ 94 sas_put_device(dev); 95 pr_warn("Port %016llx is disconnected when discovering\n", 96 SAS_ADDR(port->attached_sas_addr)); 97 return -ENODEV; 98 } 99 100 sas_init_dev(dev); 101 102 dev->port = port; 103 switch (dev->dev_type) { 104 case SAS_SATA_DEV: 105 rc = sas_ata_init(dev); 106 if (rc) { 107 rphy = NULL; 108 break; 109 } 110 fallthrough; 111 case SAS_END_DEVICE: 112 rphy = sas_end_device_alloc(port->port); 113 break; 114 case SAS_EDGE_EXPANDER_DEVICE: 115 rphy = sas_expander_alloc(port->port, 116 SAS_EDGE_EXPANDER_DEVICE); 117 break; 118 case SAS_FANOUT_EXPANDER_DEVICE: 119 rphy = sas_expander_alloc(port->port, 120 SAS_FANOUT_EXPANDER_DEVICE); 121 break; 122 default: 123 pr_warn("ERROR: Unidentified device type %d\n", dev->dev_type); 124 rphy = NULL; 125 break; 126 } 127 128 if (!rphy) { 129 sas_put_device(dev); 130 return rc; 131 } 132 133 rphy->identify.phy_identifier = phy->phy->identify.phy_identifier; 134 memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE); 135 sas_fill_in_rphy(dev, rphy); 136 sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr); 137 port->port_dev = dev; 138 dev->linkrate = port->linkrate; 139 dev->min_linkrate = port->linkrate; 140 dev->max_linkrate = port->linkrate; 141 dev->pathways = port->num_phys; 142 memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE); 143 memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE); 144 memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE); 145 port->disc.max_level = 0; 146 sas_device_set_phy(dev, port->port); 147 148 dev->rphy = rphy; 149 get_device(&dev->rphy->dev); 150 151 if (dev_is_sata(dev) || dev->dev_type == SAS_END_DEVICE) 152 list_add_tail(&dev->disco_list_node, &port->disco_list); 153 else { 154 spin_lock_irq(&port->dev_list_lock); 155 list_add_tail(&dev->dev_list_node, &port->dev_list); 156 spin_unlock_irq(&port->dev_list_lock); 157 } 158 159 spin_lock_irq(&port->phy_list_lock); 160 list_for_each_entry(phy, &port->phy_list, port_phy_el) 161 sas_phy_set_target(phy, dev); 162 spin_unlock_irq(&port->phy_list_lock); 163 164 return 0; 165 } 166 167 /* ---------- Discover and Revalidate ---------- */ 168 169 int sas_notify_lldd_dev_found(struct domain_device *dev) 170 { 171 int res = 0; 172 struct sas_ha_struct *sas_ha = dev->port->ha; 173 struct Scsi_Host *shost = sas_ha->core.shost; 174 struct sas_internal *i = to_sas_internal(shost->transportt); 175 176 if (!i->dft->lldd_dev_found) 177 return 0; 178 179 res = i->dft->lldd_dev_found(dev); 180 if (res) { 181 pr_warn("driver on host %s cannot handle device %016llx, error:%d\n", 182 dev_name(sas_ha->dev), 183 SAS_ADDR(dev->sas_addr), res); 184 return res; 185 } 186 set_bit(SAS_DEV_FOUND, &dev->state); 187 kref_get(&dev->kref); 188 return 0; 189 } 190 191 192 void sas_notify_lldd_dev_gone(struct domain_device *dev) 193 { 194 struct sas_ha_struct *sas_ha = dev->port->ha; 195 struct Scsi_Host *shost = sas_ha->core.shost; 196 struct sas_internal *i = to_sas_internal(shost->transportt); 197 198 if (!i->dft->lldd_dev_gone) 199 return; 200 201 if (test_and_clear_bit(SAS_DEV_FOUND, &dev->state)) { 202 i->dft->lldd_dev_gone(dev); 203 sas_put_device(dev); 204 } 205 } 206 207 static void sas_probe_devices(struct asd_sas_port *port) 208 { 209 struct domain_device *dev, *n; 210 211 /* devices must be domain members before link recovery and probe */ 212 list_for_each_entry(dev, &port->disco_list, disco_list_node) { 213 spin_lock_irq(&port->dev_list_lock); 214 list_add_tail(&dev->dev_list_node, &port->dev_list); 215 spin_unlock_irq(&port->dev_list_lock); 216 } 217 218 sas_probe_sata(port); 219 220 list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) { 221 int err; 222 223 err = sas_rphy_add(dev->rphy); 224 if (err) 225 sas_fail_probe(dev, __func__, err); 226 else 227 list_del_init(&dev->disco_list_node); 228 } 229 } 230 231 static void sas_suspend_devices(struct work_struct *work) 232 { 233 struct asd_sas_phy *phy; 234 struct domain_device *dev; 235 struct sas_discovery_event *ev = to_sas_discovery_event(work); 236 struct asd_sas_port *port = ev->port; 237 struct Scsi_Host *shost = port->ha->core.shost; 238 struct sas_internal *si = to_sas_internal(shost->transportt); 239 240 clear_bit(DISCE_SUSPEND, &port->disc.pending); 241 242 sas_suspend_sata(port); 243 244 /* lldd is free to forget the domain_device across the 245 * suspension, we force the issue here to keep the reference 246 * counts aligned 247 */ 248 list_for_each_entry(dev, &port->dev_list, dev_list_node) 249 sas_notify_lldd_dev_gone(dev); 250 251 /* we are suspending, so we know events are disabled and 252 * phy_list is not being mutated 253 */ 254 list_for_each_entry(phy, &port->phy_list, port_phy_el) { 255 if (si->dft->lldd_port_deformed) 256 si->dft->lldd_port_deformed(phy); 257 phy->suspended = 1; 258 port->suspended = 1; 259 } 260 } 261 262 static void sas_resume_devices(struct work_struct *work) 263 { 264 struct sas_discovery_event *ev = to_sas_discovery_event(work); 265 struct asd_sas_port *port = ev->port; 266 267 clear_bit(DISCE_RESUME, &port->disc.pending); 268 269 sas_resume_sata(port); 270 } 271 272 /** 273 * sas_discover_end_dev - discover an end device (SSP, etc) 274 * @dev: pointer to domain device of interest 275 * 276 * See comment in sas_discover_sata(). 277 */ 278 int sas_discover_end_dev(struct domain_device *dev) 279 { 280 return sas_notify_lldd_dev_found(dev); 281 } 282 283 /* ---------- Device registration and unregistration ---------- */ 284 285 void sas_free_device(struct kref *kref) 286 { 287 struct domain_device *dev = container_of(kref, typeof(*dev), kref); 288 289 put_device(&dev->rphy->dev); 290 dev->rphy = NULL; 291 292 if (dev->parent) 293 sas_put_device(dev->parent); 294 295 sas_port_put_phy(dev->phy); 296 dev->phy = NULL; 297 298 /* remove the phys and ports, everything else should be gone */ 299 if (dev_is_expander(dev->dev_type)) 300 kfree(dev->ex_dev.ex_phy); 301 302 if (dev_is_sata(dev) && dev->sata_dev.ap) { 303 ata_sas_tport_delete(dev->sata_dev.ap); 304 ata_sas_port_destroy(dev->sata_dev.ap); 305 ata_host_put(dev->sata_dev.ata_host); 306 dev->sata_dev.ata_host = NULL; 307 dev->sata_dev.ap = NULL; 308 } 309 310 kfree(dev); 311 } 312 313 static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev) 314 { 315 struct sas_ha_struct *ha = port->ha; 316 317 sas_notify_lldd_dev_gone(dev); 318 if (!dev->parent) 319 dev->port->port_dev = NULL; 320 else 321 list_del_init(&dev->siblings); 322 323 spin_lock_irq(&port->dev_list_lock); 324 list_del_init(&dev->dev_list_node); 325 if (dev_is_sata(dev)) 326 sas_ata_end_eh(dev->sata_dev.ap); 327 spin_unlock_irq(&port->dev_list_lock); 328 329 spin_lock_irq(&ha->lock); 330 if (dev->dev_type == SAS_END_DEVICE && 331 !list_empty(&dev->ssp_dev.eh_list_node)) { 332 list_del_init(&dev->ssp_dev.eh_list_node); 333 ha->eh_active--; 334 } 335 spin_unlock_irq(&ha->lock); 336 337 sas_put_device(dev); 338 } 339 340 void sas_destruct_devices(struct asd_sas_port *port) 341 { 342 struct domain_device *dev, *n; 343 344 list_for_each_entry_safe(dev, n, &port->destroy_list, disco_list_node) { 345 list_del_init(&dev->disco_list_node); 346 347 sas_remove_children(&dev->rphy->dev); 348 sas_rphy_delete(dev->rphy); 349 sas_unregister_common_dev(port, dev); 350 } 351 } 352 353 static void sas_destruct_ports(struct asd_sas_port *port) 354 { 355 struct sas_port *sas_port, *p; 356 357 list_for_each_entry_safe(sas_port, p, &port->sas_port_del_list, del_list) { 358 list_del_init(&sas_port->del_list); 359 sas_port_delete(sas_port); 360 } 361 } 362 363 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev) 364 { 365 if (!test_bit(SAS_DEV_DESTROY, &dev->state) && 366 !list_empty(&dev->disco_list_node)) { 367 /* this rphy never saw sas_rphy_add */ 368 list_del_init(&dev->disco_list_node); 369 sas_rphy_free(dev->rphy); 370 sas_unregister_common_dev(port, dev); 371 return; 372 } 373 374 if (!test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) { 375 sas_rphy_unlink(dev->rphy); 376 list_move_tail(&dev->disco_list_node, &port->destroy_list); 377 } 378 } 379 380 void sas_unregister_domain_devices(struct asd_sas_port *port, int gone) 381 { 382 struct domain_device *dev, *n; 383 384 list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node) { 385 if (gone) 386 set_bit(SAS_DEV_GONE, &dev->state); 387 sas_unregister_dev(port, dev); 388 } 389 390 list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) 391 sas_unregister_dev(port, dev); 392 393 port->port->rphy = NULL; 394 395 } 396 397 void sas_device_set_phy(struct domain_device *dev, struct sas_port *port) 398 { 399 struct sas_ha_struct *ha; 400 struct sas_phy *new_phy; 401 402 if (!dev) 403 return; 404 405 ha = dev->port->ha; 406 new_phy = sas_port_get_phy(port); 407 408 /* pin and record last seen phy */ 409 spin_lock_irq(&ha->phy_port_lock); 410 if (new_phy) { 411 sas_port_put_phy(dev->phy); 412 dev->phy = new_phy; 413 } 414 spin_unlock_irq(&ha->phy_port_lock); 415 } 416 417 /* ---------- Discovery and Revalidation ---------- */ 418 419 /** 420 * sas_discover_domain - discover the domain 421 * @work: work structure embedded in port domain device. 422 * 423 * NOTE: this process _must_ quit (return) as soon as any connection 424 * errors are encountered. Connection recovery is done elsewhere. 425 * Discover process only interrogates devices in order to discover the 426 * domain. 427 */ 428 static void sas_discover_domain(struct work_struct *work) 429 { 430 struct domain_device *dev; 431 int error = 0; 432 struct sas_discovery_event *ev = to_sas_discovery_event(work); 433 struct asd_sas_port *port = ev->port; 434 435 clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending); 436 437 if (port->port_dev) 438 return; 439 440 error = sas_get_port_device(port); 441 if (error) 442 return; 443 dev = port->port_dev; 444 445 pr_debug("DOING DISCOVERY on port %d, pid:%d\n", port->id, 446 task_pid_nr(current)); 447 448 switch (dev->dev_type) { 449 case SAS_END_DEVICE: 450 error = sas_discover_end_dev(dev); 451 break; 452 case SAS_EDGE_EXPANDER_DEVICE: 453 case SAS_FANOUT_EXPANDER_DEVICE: 454 error = sas_discover_root_expander(dev); 455 break; 456 case SAS_SATA_DEV: 457 case SAS_SATA_PM: 458 #ifdef CONFIG_SCSI_SAS_ATA 459 error = sas_discover_sata(dev); 460 break; 461 #else 462 pr_notice("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n"); 463 fallthrough; 464 #endif 465 /* Fall through - only for the #else condition above. */ 466 default: 467 error = -ENXIO; 468 pr_err("unhandled device %d\n", dev->dev_type); 469 break; 470 } 471 472 if (error) { 473 sas_rphy_free(dev->rphy); 474 list_del_init(&dev->disco_list_node); 475 spin_lock_irq(&port->dev_list_lock); 476 list_del_init(&dev->dev_list_node); 477 spin_unlock_irq(&port->dev_list_lock); 478 479 sas_put_device(dev); 480 port->port_dev = NULL; 481 } 482 483 sas_probe_devices(port); 484 485 pr_debug("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id, 486 task_pid_nr(current), error); 487 } 488 489 static void sas_revalidate_domain(struct work_struct *work) 490 { 491 int res = 0; 492 struct sas_discovery_event *ev = to_sas_discovery_event(work); 493 struct asd_sas_port *port = ev->port; 494 struct sas_ha_struct *ha = port->ha; 495 struct domain_device *ddev = port->port_dev; 496 497 /* prevent revalidation from finding sata links in recovery */ 498 mutex_lock(&ha->disco_mutex); 499 if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) { 500 pr_debug("REVALIDATION DEFERRED on port %d, pid:%d\n", 501 port->id, task_pid_nr(current)); 502 goto out; 503 } 504 505 clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending); 506 507 pr_debug("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id, 508 task_pid_nr(current)); 509 510 if (ddev && dev_is_expander(ddev->dev_type)) 511 res = sas_ex_revalidate_domain(ddev); 512 513 pr_debug("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n", 514 port->id, task_pid_nr(current), res); 515 out: 516 mutex_unlock(&ha->disco_mutex); 517 518 sas_destruct_devices(port); 519 sas_destruct_ports(port); 520 sas_probe_devices(port); 521 } 522 523 /* ---------- Events ---------- */ 524 525 static void sas_chain_work(struct sas_ha_struct *ha, struct sas_work *sw) 526 { 527 /* chained work is not subject to SA_HA_DRAINING or 528 * SAS_HA_REGISTERED, because it is either submitted in the 529 * workqueue, or known to be submitted from a context that is 530 * not racing against draining 531 */ 532 queue_work(ha->disco_q, &sw->work); 533 } 534 535 static void sas_chain_event(int event, unsigned long *pending, 536 struct sas_work *sw, 537 struct sas_ha_struct *ha) 538 { 539 if (!test_and_set_bit(event, pending)) { 540 unsigned long flags; 541 542 spin_lock_irqsave(&ha->lock, flags); 543 sas_chain_work(ha, sw); 544 spin_unlock_irqrestore(&ha->lock, flags); 545 } 546 } 547 548 void sas_discover_event(struct asd_sas_port *port, enum discover_event ev) 549 { 550 struct sas_discovery *disc; 551 552 if (!port) 553 return; 554 disc = &port->disc; 555 556 BUG_ON(ev >= DISC_NUM_EVENTS); 557 558 sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha); 559 } 560 561 /** 562 * sas_init_disc - initialize the discovery struct in the port 563 * @disc: port discovery structure 564 * @port: pointer to struct port 565 * 566 * Called when the ports are being initialized. 567 */ 568 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port) 569 { 570 int i; 571 572 static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = { 573 [DISCE_DISCOVER_DOMAIN] = sas_discover_domain, 574 [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain, 575 [DISCE_SUSPEND] = sas_suspend_devices, 576 [DISCE_RESUME] = sas_resume_devices, 577 }; 578 579 disc->pending = 0; 580 for (i = 0; i < DISC_NUM_EVENTS; i++) { 581 INIT_SAS_WORK(&disc->disc_work[i].work, sas_event_fns[i]); 582 disc->disc_work[i].port = port; 583 } 584 } 585