1 /* 2 * Serial Attached SCSI (SAS) Transport Layer initialization 3 * 4 * Copyright (C) 2005 Adaptec, Inc. All rights reserved. 5 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com> 6 * 7 * This file is licensed under GPLv2. 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License as 11 * published by the Free Software Foundation; either version 2 of the 12 * License, or (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 22 * USA 23 * 24 */ 25 26 #include <linux/module.h> 27 #include <linux/slab.h> 28 #include <linux/init.h> 29 #include <linux/device.h> 30 #include <linux/spinlock.h> 31 #include <scsi/sas_ata.h> 32 #include <scsi/scsi_host.h> 33 #include <scsi/scsi_device.h> 34 #include <scsi/scsi_transport.h> 35 #include <scsi/scsi_transport_sas.h> 36 37 #include "sas_internal.h" 38 39 #include "../scsi_sas_internal.h" 40 41 static struct kmem_cache *sas_task_cache; 42 43 struct sas_task *sas_alloc_task(gfp_t flags) 44 { 45 struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags); 46 47 if (task) { 48 spin_lock_init(&task->task_state_lock); 49 task->task_state_flags = SAS_TASK_STATE_PENDING; 50 } 51 52 return task; 53 } 54 EXPORT_SYMBOL_GPL(sas_alloc_task); 55 56 struct sas_task *sas_alloc_slow_task(gfp_t flags) 57 { 58 struct sas_task *task = sas_alloc_task(flags); 59 struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags); 60 61 if (!task || !slow) { 62 if (task) 63 kmem_cache_free(sas_task_cache, task); 64 kfree(slow); 65 return NULL; 66 } 67 68 task->slow_task = slow; 69 init_timer(&slow->timer); 70 init_completion(&slow->completion); 71 72 return task; 73 } 74 EXPORT_SYMBOL_GPL(sas_alloc_slow_task); 75 76 void sas_free_task(struct sas_task *task) 77 { 78 if (task) { 79 kfree(task->slow_task); 80 kmem_cache_free(sas_task_cache, task); 81 } 82 } 83 EXPORT_SYMBOL_GPL(sas_free_task); 84 85 /*------------ SAS addr hash -----------*/ 86 void sas_hash_addr(u8 *hashed, const u8 *sas_addr) 87 { 88 const u32 poly = 0x00DB2777; 89 u32 r = 0; 90 int i; 91 92 for (i = 0; i < 8; i++) { 93 int b; 94 for (b = 7; b >= 0; b--) { 95 r <<= 1; 96 if ((1 << b) & sas_addr[i]) { 97 if (!(r & 0x01000000)) 98 r ^= poly; 99 } else if (r & 0x01000000) 100 r ^= poly; 101 } 102 } 103 104 hashed[0] = (r >> 16) & 0xFF; 105 hashed[1] = (r >> 8) & 0xFF ; 106 hashed[2] = r & 0xFF; 107 } 108 109 110 /* ---------- HA events ---------- */ 111 112 void sas_hae_reset(struct work_struct *work) 113 { 114 struct sas_ha_event *ev = to_sas_ha_event(work); 115 struct sas_ha_struct *ha = ev->ha; 116 117 clear_bit(HAE_RESET, &ha->pending); 118 } 119 120 int sas_register_ha(struct sas_ha_struct *sas_ha) 121 { 122 int error = 0; 123 124 mutex_init(&sas_ha->disco_mutex); 125 spin_lock_init(&sas_ha->phy_port_lock); 126 sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr); 127 128 set_bit(SAS_HA_REGISTERED, &sas_ha->state); 129 spin_lock_init(&sas_ha->lock); 130 mutex_init(&sas_ha->drain_mutex); 131 init_waitqueue_head(&sas_ha->eh_wait_q); 132 INIT_LIST_HEAD(&sas_ha->defer_q); 133 INIT_LIST_HEAD(&sas_ha->eh_dev_q); 134 135 error = sas_register_phys(sas_ha); 136 if (error) { 137 printk(KERN_NOTICE "couldn't register sas phys:%d\n", error); 138 return error; 139 } 140 141 error = sas_register_ports(sas_ha); 142 if (error) { 143 printk(KERN_NOTICE "couldn't register sas ports:%d\n", error); 144 goto Undo_phys; 145 } 146 147 error = sas_init_events(sas_ha); 148 if (error) { 149 printk(KERN_NOTICE "couldn't start event thread:%d\n", error); 150 goto Undo_ports; 151 } 152 153 INIT_LIST_HEAD(&sas_ha->eh_done_q); 154 INIT_LIST_HEAD(&sas_ha->eh_ata_q); 155 156 return 0; 157 158 Undo_ports: 159 sas_unregister_ports(sas_ha); 160 Undo_phys: 161 162 return error; 163 } 164 165 static void sas_disable_events(struct sas_ha_struct *sas_ha) 166 { 167 /* Set the state to unregistered to avoid further unchained 168 * events to be queued, and flush any in-progress drainers 169 */ 170 mutex_lock(&sas_ha->drain_mutex); 171 spin_lock_irq(&sas_ha->lock); 172 clear_bit(SAS_HA_REGISTERED, &sas_ha->state); 173 spin_unlock_irq(&sas_ha->lock); 174 __sas_drain_work(sas_ha); 175 mutex_unlock(&sas_ha->drain_mutex); 176 } 177 178 int sas_unregister_ha(struct sas_ha_struct *sas_ha) 179 { 180 sas_disable_events(sas_ha); 181 sas_unregister_ports(sas_ha); 182 183 /* flush unregistration work */ 184 mutex_lock(&sas_ha->drain_mutex); 185 __sas_drain_work(sas_ha); 186 mutex_unlock(&sas_ha->drain_mutex); 187 188 return 0; 189 } 190 191 static int sas_get_linkerrors(struct sas_phy *phy) 192 { 193 if (scsi_is_sas_phy_local(phy)) { 194 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 195 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 196 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 197 struct sas_internal *i = 198 to_sas_internal(sas_ha->core.shost->transportt); 199 200 return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL); 201 } 202 203 return sas_smp_get_phy_events(phy); 204 } 205 206 int sas_try_ata_reset(struct asd_sas_phy *asd_phy) 207 { 208 struct domain_device *dev = NULL; 209 210 /* try to route user requested link resets through libata */ 211 if (asd_phy->port) 212 dev = asd_phy->port->port_dev; 213 214 /* validate that dev has been probed */ 215 if (dev) 216 dev = sas_find_dev_by_rphy(dev->rphy); 217 218 if (dev && dev_is_sata(dev)) { 219 sas_ata_schedule_reset(dev); 220 sas_ata_wait_eh(dev); 221 return 0; 222 } 223 224 return -ENODEV; 225 } 226 227 /** 228 * transport_sas_phy_reset - reset a phy and permit libata to manage the link 229 * 230 * phy reset request via sysfs in host workqueue context so we know we 231 * can block on eh and safely traverse the domain_device topology 232 */ 233 static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset) 234 { 235 enum phy_func reset_type; 236 237 if (hard_reset) 238 reset_type = PHY_FUNC_HARD_RESET; 239 else 240 reset_type = PHY_FUNC_LINK_RESET; 241 242 if (scsi_is_sas_phy_local(phy)) { 243 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 244 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 245 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 246 struct sas_internal *i = 247 to_sas_internal(sas_ha->core.shost->transportt); 248 249 if (!hard_reset && sas_try_ata_reset(asd_phy) == 0) 250 return 0; 251 return i->dft->lldd_control_phy(asd_phy, reset_type, NULL); 252 } else { 253 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 254 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 255 struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number); 256 257 if (ata_dev && !hard_reset) { 258 sas_ata_schedule_reset(ata_dev); 259 sas_ata_wait_eh(ata_dev); 260 return 0; 261 } else 262 return sas_smp_phy_control(ddev, phy->number, reset_type, NULL); 263 } 264 } 265 266 static int sas_phy_enable(struct sas_phy *phy, int enable) 267 { 268 int ret; 269 enum phy_func cmd; 270 271 if (enable) 272 cmd = PHY_FUNC_LINK_RESET; 273 else 274 cmd = PHY_FUNC_DISABLE; 275 276 if (scsi_is_sas_phy_local(phy)) { 277 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 278 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 279 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 280 struct sas_internal *i = 281 to_sas_internal(sas_ha->core.shost->transportt); 282 283 if (enable) 284 ret = transport_sas_phy_reset(phy, 0); 285 else 286 ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL); 287 } else { 288 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 289 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 290 291 if (enable) 292 ret = transport_sas_phy_reset(phy, 0); 293 else 294 ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL); 295 } 296 return ret; 297 } 298 299 int sas_phy_reset(struct sas_phy *phy, int hard_reset) 300 { 301 int ret; 302 enum phy_func reset_type; 303 304 if (!phy->enabled) 305 return -ENODEV; 306 307 if (hard_reset) 308 reset_type = PHY_FUNC_HARD_RESET; 309 else 310 reset_type = PHY_FUNC_LINK_RESET; 311 312 if (scsi_is_sas_phy_local(phy)) { 313 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 314 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 315 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 316 struct sas_internal *i = 317 to_sas_internal(sas_ha->core.shost->transportt); 318 319 ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL); 320 } else { 321 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 322 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 323 ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL); 324 } 325 return ret; 326 } 327 328 int sas_set_phy_speed(struct sas_phy *phy, 329 struct sas_phy_linkrates *rates) 330 { 331 int ret; 332 333 if ((rates->minimum_linkrate && 334 rates->minimum_linkrate > phy->maximum_linkrate) || 335 (rates->maximum_linkrate && 336 rates->maximum_linkrate < phy->minimum_linkrate)) 337 return -EINVAL; 338 339 if (rates->minimum_linkrate && 340 rates->minimum_linkrate < phy->minimum_linkrate_hw) 341 rates->minimum_linkrate = phy->minimum_linkrate_hw; 342 343 if (rates->maximum_linkrate && 344 rates->maximum_linkrate > phy->maximum_linkrate_hw) 345 rates->maximum_linkrate = phy->maximum_linkrate_hw; 346 347 if (scsi_is_sas_phy_local(phy)) { 348 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 349 struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost); 350 struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number]; 351 struct sas_internal *i = 352 to_sas_internal(sas_ha->core.shost->transportt); 353 354 ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE, 355 rates); 356 } else { 357 struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent); 358 struct domain_device *ddev = sas_find_dev_by_rphy(rphy); 359 ret = sas_smp_phy_control(ddev, phy->number, 360 PHY_FUNC_LINK_RESET, rates); 361 362 } 363 364 return ret; 365 } 366 367 void sas_prep_resume_ha(struct sas_ha_struct *ha) 368 { 369 int i; 370 371 set_bit(SAS_HA_REGISTERED, &ha->state); 372 373 /* clear out any stale link events/data from the suspension path */ 374 for (i = 0; i < ha->num_phys; i++) { 375 struct asd_sas_phy *phy = ha->sas_phy[i]; 376 377 memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE); 378 phy->port_events_pending = 0; 379 phy->phy_events_pending = 0; 380 phy->frame_rcvd_size = 0; 381 } 382 } 383 EXPORT_SYMBOL(sas_prep_resume_ha); 384 385 static int phys_suspended(struct sas_ha_struct *ha) 386 { 387 int i, rc = 0; 388 389 for (i = 0; i < ha->num_phys; i++) { 390 struct asd_sas_phy *phy = ha->sas_phy[i]; 391 392 if (phy->suspended) 393 rc++; 394 } 395 396 return rc; 397 } 398 399 void sas_resume_ha(struct sas_ha_struct *ha) 400 { 401 const unsigned long tmo = msecs_to_jiffies(25000); 402 int i; 403 404 /* deform ports on phys that did not resume 405 * at this point we may be racing the phy coming back (as posted 406 * by the lldd). So we post the event and once we are in the 407 * libsas context check that the phy remains suspended before 408 * tearing it down. 409 */ 410 i = phys_suspended(ha); 411 if (i) 412 dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n", 413 i, i > 1 ? "s" : ""); 414 wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo); 415 for (i = 0; i < ha->num_phys; i++) { 416 struct asd_sas_phy *phy = ha->sas_phy[i]; 417 418 if (phy->suspended) { 419 dev_warn(&phy->phy->dev, "resume timeout\n"); 420 sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT); 421 } 422 } 423 424 /* all phys are back up or timed out, turn on i/o so we can 425 * flush out disks that did not return 426 */ 427 scsi_unblock_requests(ha->core.shost); 428 sas_drain_work(ha); 429 } 430 EXPORT_SYMBOL(sas_resume_ha); 431 432 void sas_suspend_ha(struct sas_ha_struct *ha) 433 { 434 int i; 435 436 sas_disable_events(ha); 437 scsi_block_requests(ha->core.shost); 438 for (i = 0; i < ha->num_phys; i++) { 439 struct asd_sas_port *port = ha->sas_port[i]; 440 441 sas_discover_event(port, DISCE_SUSPEND); 442 } 443 444 /* flush suspend events while unregistered */ 445 mutex_lock(&ha->drain_mutex); 446 __sas_drain_work(ha); 447 mutex_unlock(&ha->drain_mutex); 448 } 449 EXPORT_SYMBOL(sas_suspend_ha); 450 451 static void sas_phy_release(struct sas_phy *phy) 452 { 453 kfree(phy->hostdata); 454 phy->hostdata = NULL; 455 } 456 457 static void phy_reset_work(struct work_struct *work) 458 { 459 struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work); 460 461 d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset); 462 } 463 464 static void phy_enable_work(struct work_struct *work) 465 { 466 struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work); 467 468 d->enable_result = sas_phy_enable(d->phy, d->enable); 469 } 470 471 static int sas_phy_setup(struct sas_phy *phy) 472 { 473 struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL); 474 475 if (!d) 476 return -ENOMEM; 477 478 mutex_init(&d->event_lock); 479 INIT_SAS_WORK(&d->reset_work, phy_reset_work); 480 INIT_SAS_WORK(&d->enable_work, phy_enable_work); 481 d->phy = phy; 482 phy->hostdata = d; 483 484 return 0; 485 } 486 487 static int queue_phy_reset(struct sas_phy *phy, int hard_reset) 488 { 489 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 490 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost); 491 struct sas_phy_data *d = phy->hostdata; 492 int rc; 493 494 if (!d) 495 return -ENOMEM; 496 497 /* libsas workqueue coordinates ata-eh reset with discovery */ 498 mutex_lock(&d->event_lock); 499 d->reset_result = 0; 500 d->hard_reset = hard_reset; 501 502 spin_lock_irq(&ha->lock); 503 sas_queue_work(ha, &d->reset_work); 504 spin_unlock_irq(&ha->lock); 505 506 rc = sas_drain_work(ha); 507 if (rc == 0) 508 rc = d->reset_result; 509 mutex_unlock(&d->event_lock); 510 511 return rc; 512 } 513 514 static int queue_phy_enable(struct sas_phy *phy, int enable) 515 { 516 struct Scsi_Host *shost = dev_to_shost(phy->dev.parent); 517 struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost); 518 struct sas_phy_data *d = phy->hostdata; 519 int rc; 520 521 if (!d) 522 return -ENOMEM; 523 524 /* libsas workqueue coordinates ata-eh reset with discovery */ 525 mutex_lock(&d->event_lock); 526 d->enable_result = 0; 527 d->enable = enable; 528 529 spin_lock_irq(&ha->lock); 530 sas_queue_work(ha, &d->enable_work); 531 spin_unlock_irq(&ha->lock); 532 533 rc = sas_drain_work(ha); 534 if (rc == 0) 535 rc = d->enable_result; 536 mutex_unlock(&d->event_lock); 537 538 return rc; 539 } 540 541 static struct sas_function_template sft = { 542 .phy_enable = queue_phy_enable, 543 .phy_reset = queue_phy_reset, 544 .phy_setup = sas_phy_setup, 545 .phy_release = sas_phy_release, 546 .set_phy_speed = sas_set_phy_speed, 547 .get_linkerrors = sas_get_linkerrors, 548 .smp_handler = sas_smp_handler, 549 }; 550 551 struct scsi_transport_template * 552 sas_domain_attach_transport(struct sas_domain_function_template *dft) 553 { 554 struct scsi_transport_template *stt = sas_attach_transport(&sft); 555 struct sas_internal *i; 556 557 if (!stt) 558 return stt; 559 560 i = to_sas_internal(stt); 561 i->dft = dft; 562 stt->create_work_queue = 1; 563 stt->eh_strategy_handler = sas_scsi_recover_host; 564 565 return stt; 566 } 567 EXPORT_SYMBOL_GPL(sas_domain_attach_transport); 568 569 /* ---------- SAS Class register/unregister ---------- */ 570 571 static int __init sas_class_init(void) 572 { 573 sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN); 574 if (!sas_task_cache) 575 return -ENOMEM; 576 577 return 0; 578 } 579 580 static void __exit sas_class_exit(void) 581 { 582 kmem_cache_destroy(sas_task_cache); 583 } 584 585 MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>"); 586 MODULE_DESCRIPTION("SAS Transport Layer"); 587 MODULE_LICENSE("GPL v2"); 588 589 module_init(sas_class_init); 590 module_exit(sas_class_exit); 591 592 EXPORT_SYMBOL_GPL(sas_register_ha); 593 EXPORT_SYMBOL_GPL(sas_unregister_ha); 594