1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * SCSI RDMA (SRP) transport class 4 * 5 * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org> 6 */ 7#include <linux/init.h> 8#include <linux/module.h> 9#include <linux/jiffies.h> 10#include <linux/err.h> 11#include <linux/slab.h> 12#include <linux/string.h> 13 14#include <scsi/scsi.h> 15#include <scsi/scsi_cmnd.h> 16#include <scsi/scsi_device.h> 17#include <scsi/scsi_host.h> 18#include <scsi/scsi_transport.h> 19#include <scsi/scsi_transport_srp.h> 20#include "scsi_priv.h" 21 22struct srp_host_attrs { 23 atomic_t next_port_id; 24}; 25#define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data) 26 27#define SRP_HOST_ATTRS 0 28#define SRP_RPORT_ATTRS 8 29 30struct srp_internal { 31 struct scsi_transport_template t; 32 struct srp_function_template *f; 33 34 struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1]; 35 36 struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1]; 37 struct transport_container rport_attr_cont; 38}; 39 40static int scsi_is_srp_rport(const struct device *dev); 41 42#define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t) 43 44#define dev_to_rport(d) container_of(d, struct srp_rport, dev) 45#define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent) 46static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) 47{ 48 return dev_to_shost(r->dev.parent); 49} 50 51static int find_child_rport(struct device *dev, void *data) 52{ 53 struct device **child = data; 54 55 if (scsi_is_srp_rport(dev)) { 56 WARN_ON_ONCE(*child); 57 *child = dev; 58 } 59 return 0; 60} 61 62static inline struct srp_rport *shost_to_rport(struct Scsi_Host *shost) 63{ 64 struct device *child = NULL; 65 66 WARN_ON_ONCE(device_for_each_child(&shost->shost_gendev, &child, 67 find_child_rport) < 0); 68 return child ? dev_to_rport(child) : NULL; 69} 70 71/** 72 * srp_tmo_valid() - check timeout combination validity 73 * @reconnect_delay: Reconnect delay in seconds. 74 * @fast_io_fail_tmo: Fast I/O fail timeout in seconds. 75 * @dev_loss_tmo: Device loss timeout in seconds. 76 * 77 * The combination of the timeout parameters must be such that SCSI commands 78 * are finished in a reasonable time. Hence do not allow the fast I/O fail 79 * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT nor allow dev_loss_tmo to 80 * exceed that limit if failing I/O fast has been disabled. Furthermore, these 81 * parameters must be such that multipath can detect failed paths timely. 82 * Hence do not allow all three parameters to be disabled simultaneously. 83 */ 84int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, long dev_loss_tmo) 85{ 86 if (reconnect_delay < 0 && fast_io_fail_tmo < 0 && dev_loss_tmo < 0) 87 return -EINVAL; 88 if (reconnect_delay == 0) 89 return -EINVAL; 90 if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) 91 return -EINVAL; 92 if (fast_io_fail_tmo < 0 && 93 dev_loss_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) 94 return -EINVAL; 95 if (dev_loss_tmo >= LONG_MAX / HZ) 96 return -EINVAL; 97 if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 && 98 fast_io_fail_tmo >= dev_loss_tmo) 99 return -EINVAL; 100 return 0; 101} 102EXPORT_SYMBOL_GPL(srp_tmo_valid); 103 104static int srp_host_setup(struct transport_container *tc, struct device *dev, 105 struct device *cdev) 106{ 107 struct Scsi_Host *shost = dev_to_shost(dev); 108 struct srp_host_attrs *srp_host = to_srp_host_attrs(shost); 109 110 atomic_set(&srp_host->next_port_id, 0); 111 return 0; 112} 113 114static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup, 115 NULL, NULL); 116 117static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports", 118 NULL, NULL, NULL); 119 120static ssize_t 121show_srp_rport_id(struct device *dev, struct device_attribute *attr, 122 char *buf) 123{ 124 struct srp_rport *rport = transport_class_to_srp_rport(dev); 125 return sprintf(buf, "%16phC\n", rport->port_id); 126} 127 128static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL); 129 130static const struct { 131 u32 value; 132 char *name; 133} srp_rport_role_names[] = { 134 {SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"}, 135 {SRP_RPORT_ROLE_TARGET, "SRP Target"}, 136}; 137 138static ssize_t 139show_srp_rport_roles(struct device *dev, struct device_attribute *attr, 140 char *buf) 141{ 142 struct srp_rport *rport = transport_class_to_srp_rport(dev); 143 int i; 144 char *name = NULL; 145 146 for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++) 147 if (srp_rport_role_names[i].value == rport->roles) { 148 name = srp_rport_role_names[i].name; 149 break; 150 } 151 return sprintf(buf, "%s\n", name ? : "unknown"); 152} 153 154static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL); 155 156static ssize_t store_srp_rport_delete(struct device *dev, 157 struct device_attribute *attr, 158 const char *buf, size_t count) 159{ 160 struct srp_rport *rport = transport_class_to_srp_rport(dev); 161 struct Scsi_Host *shost = dev_to_shost(dev); 162 struct srp_internal *i = to_srp_internal(shost->transportt); 163 164 if (i->f->rport_delete) { 165 i->f->rport_delete(rport); 166 return count; 167 } else { 168 return -ENOSYS; 169 } 170} 171 172static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete); 173 174static ssize_t show_srp_rport_state(struct device *dev, 175 struct device_attribute *attr, 176 char *buf) 177{ 178 static const char *const state_name[] = { 179 [SRP_RPORT_RUNNING] = "running", 180 [SRP_RPORT_BLOCKED] = "blocked", 181 [SRP_RPORT_FAIL_FAST] = "fail-fast", 182 [SRP_RPORT_LOST] = "lost", 183 }; 184 struct srp_rport *rport = transport_class_to_srp_rport(dev); 185 enum srp_rport_state state = rport->state; 186 187 return sprintf(buf, "%s\n", 188 (unsigned)state < ARRAY_SIZE(state_name) ? 189 state_name[state] : "???"); 190} 191 192static DEVICE_ATTR(state, S_IRUGO, show_srp_rport_state, NULL); 193 194static ssize_t srp_show_tmo(char *buf, int tmo) 195{ 196 return tmo >= 0 ? sprintf(buf, "%d\n", tmo) : sprintf(buf, "off\n"); 197} 198 199int srp_parse_tmo(int *tmo, const char *buf) 200{ 201 int res = 0; 202 203 if (strncmp(buf, "off", 3) != 0) 204 res = kstrtoint(buf, 0, tmo); 205 else 206 *tmo = -1; 207 208 return res; 209} 210EXPORT_SYMBOL(srp_parse_tmo); 211 212static ssize_t show_reconnect_delay(struct device *dev, 213 struct device_attribute *attr, char *buf) 214{ 215 struct srp_rport *rport = transport_class_to_srp_rport(dev); 216 217 return srp_show_tmo(buf, rport->reconnect_delay); 218} 219 220static ssize_t store_reconnect_delay(struct device *dev, 221 struct device_attribute *attr, 222 const char *buf, const size_t count) 223{ 224 struct srp_rport *rport = transport_class_to_srp_rport(dev); 225 int res, delay; 226 227 res = srp_parse_tmo(&delay, buf); 228 if (res) 229 goto out; 230 res = srp_tmo_valid(delay, rport->fast_io_fail_tmo, 231 rport->dev_loss_tmo); 232 if (res) 233 goto out; 234 235 if (rport->reconnect_delay <= 0 && delay > 0 && 236 rport->state != SRP_RPORT_RUNNING) { 237 queue_delayed_work(system_long_wq, &rport->reconnect_work, 238 delay * HZ); 239 } else if (delay <= 0) { 240 cancel_delayed_work(&rport->reconnect_work); 241 } 242 rport->reconnect_delay = delay; 243 res = count; 244 245out: 246 return res; 247} 248 249static DEVICE_ATTR(reconnect_delay, S_IRUGO | S_IWUSR, show_reconnect_delay, 250 store_reconnect_delay); 251 252static ssize_t show_failed_reconnects(struct device *dev, 253 struct device_attribute *attr, char *buf) 254{ 255 struct srp_rport *rport = transport_class_to_srp_rport(dev); 256 257 return sprintf(buf, "%d\n", rport->failed_reconnects); 258} 259 260static DEVICE_ATTR(failed_reconnects, S_IRUGO, show_failed_reconnects, NULL); 261 262static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev, 263 struct device_attribute *attr, 264 char *buf) 265{ 266 struct srp_rport *rport = transport_class_to_srp_rport(dev); 267 268 return srp_show_tmo(buf, rport->fast_io_fail_tmo); 269} 270 271static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev, 272 struct device_attribute *attr, 273 const char *buf, size_t count) 274{ 275 struct srp_rport *rport = transport_class_to_srp_rport(dev); 276 int res; 277 int fast_io_fail_tmo; 278 279 res = srp_parse_tmo(&fast_io_fail_tmo, buf); 280 if (res) 281 goto out; 282 res = srp_tmo_valid(rport->reconnect_delay, fast_io_fail_tmo, 283 rport->dev_loss_tmo); 284 if (res) 285 goto out; 286 rport->fast_io_fail_tmo = fast_io_fail_tmo; 287 res = count; 288 289out: 290 return res; 291} 292 293static DEVICE_ATTR(fast_io_fail_tmo, S_IRUGO | S_IWUSR, 294 show_srp_rport_fast_io_fail_tmo, 295 store_srp_rport_fast_io_fail_tmo); 296 297static ssize_t show_srp_rport_dev_loss_tmo(struct device *dev, 298 struct device_attribute *attr, 299 char *buf) 300{ 301 struct srp_rport *rport = transport_class_to_srp_rport(dev); 302 303 return srp_show_tmo(buf, rport->dev_loss_tmo); 304} 305 306static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev, 307 struct device_attribute *attr, 308 const char *buf, size_t count) 309{ 310 struct srp_rport *rport = transport_class_to_srp_rport(dev); 311 int res; 312 int dev_loss_tmo; 313 314 res = srp_parse_tmo(&dev_loss_tmo, buf); 315 if (res) 316 goto out; 317 res = srp_tmo_valid(rport->reconnect_delay, rport->fast_io_fail_tmo, 318 dev_loss_tmo); 319 if (res) 320 goto out; 321 rport->dev_loss_tmo = dev_loss_tmo; 322 res = count; 323 324out: 325 return res; 326} 327 328static DEVICE_ATTR(dev_loss_tmo, S_IRUGO | S_IWUSR, 329 show_srp_rport_dev_loss_tmo, 330 store_srp_rport_dev_loss_tmo); 331 332static int srp_rport_set_state(struct srp_rport *rport, 333 enum srp_rport_state new_state) 334{ 335 enum srp_rport_state old_state = rport->state; 336 337 lockdep_assert_held(&rport->mutex); 338 339 switch (new_state) { 340 case SRP_RPORT_RUNNING: 341 switch (old_state) { 342 case SRP_RPORT_LOST: 343 goto invalid; 344 default: 345 break; 346 } 347 break; 348 case SRP_RPORT_BLOCKED: 349 switch (old_state) { 350 case SRP_RPORT_RUNNING: 351 break; 352 default: 353 goto invalid; 354 } 355 break; 356 case SRP_RPORT_FAIL_FAST: 357 switch (old_state) { 358 case SRP_RPORT_LOST: 359 goto invalid; 360 default: 361 break; 362 } 363 break; 364 case SRP_RPORT_LOST: 365 break; 366 } 367 rport->state = new_state; 368 return 0; 369 370invalid: 371 return -EINVAL; 372} 373 374/** 375 * srp_reconnect_work() - reconnect and schedule a new attempt if necessary 376 * @work: Work structure used for scheduling this operation. 377 */ 378static void srp_reconnect_work(struct work_struct *work) 379{ 380 struct srp_rport *rport = container_of(to_delayed_work(work), 381 struct srp_rport, reconnect_work); 382 struct Scsi_Host *shost = rport_to_shost(rport); 383 int delay, res; 384 385 res = srp_reconnect_rport(rport); 386 if (res != 0) { 387 shost_printk(KERN_ERR, shost, 388 "reconnect attempt %d failed (%d)\n", 389 ++rport->failed_reconnects, res); 390 delay = rport->reconnect_delay * 391 min(100, max(1, rport->failed_reconnects - 10)); 392 if (delay > 0) 393 queue_delayed_work(system_long_wq, 394 &rport->reconnect_work, delay * HZ); 395 } 396} 397 398/* 399 * scsi_block_targets() must have been called before this function is 400 * called to guarantee that no .queuecommand() calls are in progress. 401 */ 402static void __rport_fail_io_fast(struct srp_rport *rport) 403{ 404 struct Scsi_Host *shost = rport_to_shost(rport); 405 struct srp_internal *i; 406 407 lockdep_assert_held(&rport->mutex); 408 409 if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST)) 410 return; 411 412 scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); 413 414 /* Involve the LLD if possible to terminate all I/O on the rport. */ 415 i = to_srp_internal(shost->transportt); 416 if (i->f->terminate_rport_io) 417 i->f->terminate_rport_io(rport); 418} 419 420/** 421 * rport_fast_io_fail_timedout() - fast I/O failure timeout handler 422 * @work: Work structure used for scheduling this operation. 423 */ 424static void rport_fast_io_fail_timedout(struct work_struct *work) 425{ 426 struct srp_rport *rport = container_of(to_delayed_work(work), 427 struct srp_rport, fast_io_fail_work); 428 struct Scsi_Host *shost = rport_to_shost(rport); 429 430 pr_info("fast_io_fail_tmo expired for SRP %s / %s.\n", 431 dev_name(&rport->dev), dev_name(&shost->shost_gendev)); 432 433 mutex_lock(&rport->mutex); 434 if (rport->state == SRP_RPORT_BLOCKED) 435 __rport_fail_io_fast(rport); 436 mutex_unlock(&rport->mutex); 437} 438 439/** 440 * rport_dev_loss_timedout() - device loss timeout handler 441 * @work: Work structure used for scheduling this operation. 442 */ 443static void rport_dev_loss_timedout(struct work_struct *work) 444{ 445 struct srp_rport *rport = container_of(to_delayed_work(work), 446 struct srp_rport, dev_loss_work); 447 struct Scsi_Host *shost = rport_to_shost(rport); 448 struct srp_internal *i = to_srp_internal(shost->transportt); 449 450 pr_info("dev_loss_tmo expired for SRP %s / %s.\n", 451 dev_name(&rport->dev), dev_name(&shost->shost_gendev)); 452 453 mutex_lock(&rport->mutex); 454 WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0); 455 scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); 456 mutex_unlock(&rport->mutex); 457 458 i->f->rport_delete(rport); 459} 460 461static void __srp_start_tl_fail_timers(struct srp_rport *rport) 462{ 463 struct Scsi_Host *shost = rport_to_shost(rport); 464 int delay, fast_io_fail_tmo, dev_loss_tmo; 465 466 lockdep_assert_held(&rport->mutex); 467 468 delay = rport->reconnect_delay; 469 fast_io_fail_tmo = rport->fast_io_fail_tmo; 470 dev_loss_tmo = rport->dev_loss_tmo; 471 pr_debug("%s current state: %d\n", dev_name(&shost->shost_gendev), 472 rport->state); 473 474 if (rport->state == SRP_RPORT_LOST) 475 return; 476 if (delay > 0) 477 queue_delayed_work(system_long_wq, &rport->reconnect_work, 478 1UL * delay * HZ); 479 if ((fast_io_fail_tmo >= 0 || dev_loss_tmo >= 0) && 480 srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) { 481 pr_debug("%s new state: %d\n", dev_name(&shost->shost_gendev), 482 rport->state); 483 scsi_block_targets(shost, &shost->shost_gendev); 484 if (fast_io_fail_tmo >= 0) 485 queue_delayed_work(system_long_wq, 486 &rport->fast_io_fail_work, 487 1UL * fast_io_fail_tmo * HZ); 488 if (dev_loss_tmo >= 0) 489 queue_delayed_work(system_long_wq, 490 &rport->dev_loss_work, 491 1UL * dev_loss_tmo * HZ); 492 } 493} 494 495/** 496 * srp_start_tl_fail_timers() - start the transport layer failure timers 497 * @rport: SRP target port. 498 * 499 * Start the transport layer fast I/O failure and device loss timers. Do not 500 * modify a timer that was already started. 501 */ 502void srp_start_tl_fail_timers(struct srp_rport *rport) 503{ 504 mutex_lock(&rport->mutex); 505 __srp_start_tl_fail_timers(rport); 506 mutex_unlock(&rport->mutex); 507} 508EXPORT_SYMBOL(srp_start_tl_fail_timers); 509 510/** 511 * srp_reconnect_rport() - reconnect to an SRP target port 512 * @rport: SRP target port. 513 * 514 * Blocks SCSI command queueing before invoking reconnect() such that 515 * queuecommand() won't be invoked concurrently with reconnect() from outside 516 * the SCSI EH. This is important since a reconnect() implementation may 517 * reallocate resources needed by queuecommand(). 518 * 519 * Notes: 520 * - This function neither waits until outstanding requests have finished nor 521 * tries to abort these. It is the responsibility of the reconnect() 522 * function to finish outstanding commands before reconnecting to the target 523 * port. 524 * - It is the responsibility of the caller to ensure that the resources 525 * reallocated by the reconnect() function won't be used while this function 526 * is in progress. One possible strategy is to invoke this function from 527 * the context of the SCSI EH thread only. Another possible strategy is to 528 * lock the rport mutex inside each SCSI LLD callback that can be invoked by 529 * the SCSI EH (the scsi_host_template.eh_*() functions and also the 530 * scsi_host_template.queuecommand() function). 531 */ 532int srp_reconnect_rport(struct srp_rport *rport) 533{ 534 struct Scsi_Host *shost = rport_to_shost(rport); 535 struct srp_internal *i = to_srp_internal(shost->transportt); 536 struct scsi_device *sdev; 537 int res; 538 539 pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev)); 540 541 res = mutex_lock_interruptible(&rport->mutex); 542 if (res) 543 goto out; 544 if (rport->state != SRP_RPORT_FAIL_FAST && rport->state != SRP_RPORT_LOST) 545 /* 546 * sdev state must be SDEV_TRANSPORT_OFFLINE, transition 547 * to SDEV_BLOCK is illegal. Calling scsi_target_unblock() 548 * later is ok though, scsi_internal_device_unblock_nowait() 549 * treats SDEV_TRANSPORT_OFFLINE like SDEV_BLOCK. 550 */ 551 scsi_block_targets(shost, &shost->shost_gendev); 552 res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV; 553 pr_debug("%s (state %d): transport.reconnect() returned %d\n", 554 dev_name(&shost->shost_gendev), rport->state, res); 555 if (res == 0) { 556 cancel_delayed_work(&rport->fast_io_fail_work); 557 cancel_delayed_work(&rport->dev_loss_work); 558 559 rport->failed_reconnects = 0; 560 srp_rport_set_state(rport, SRP_RPORT_RUNNING); 561 scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING); 562 /* 563 * If the SCSI error handler has offlined one or more devices, 564 * invoking scsi_target_unblock() won't change the state of 565 * these devices into running so do that explicitly. 566 */ 567 shost_for_each_device(sdev, shost) { 568 mutex_lock(&sdev->state_mutex); 569 if (sdev->sdev_state == SDEV_OFFLINE) 570 sdev->sdev_state = SDEV_RUNNING; 571 mutex_unlock(&sdev->state_mutex); 572 } 573 } else if (rport->state == SRP_RPORT_RUNNING) { 574 /* 575 * srp_reconnect_rport() has been invoked with fast_io_fail 576 * and dev_loss off. Mark the port as failed and start the TL 577 * failure timers if these had not yet been started. 578 */ 579 __rport_fail_io_fast(rport); 580 __srp_start_tl_fail_timers(rport); 581 } else if (rport->state != SRP_RPORT_BLOCKED) { 582 scsi_target_unblock(&shost->shost_gendev, 583 SDEV_TRANSPORT_OFFLINE); 584 } 585 mutex_unlock(&rport->mutex); 586 587out: 588 return res; 589} 590EXPORT_SYMBOL(srp_reconnect_rport); 591 592/** 593 * srp_timed_out() - SRP transport intercept of the SCSI timeout EH 594 * @scmd: SCSI command. 595 * 596 * If a timeout occurs while an rport is in the blocked state, ask the SCSI 597 * EH to continue waiting (SCSI_EH_RESET_TIMER). Otherwise let the SCSI core 598 * handle the timeout (SCSI_EH_NOT_HANDLED). 599 * 600 * Note: This function is called from soft-IRQ context and with the request 601 * queue lock held. 602 */ 603enum scsi_timeout_action srp_timed_out(struct scsi_cmnd *scmd) 604{ 605 struct scsi_device *sdev = scmd->device; 606 struct Scsi_Host *shost = sdev->host; 607 struct srp_internal *i = to_srp_internal(shost->transportt); 608 struct srp_rport *rport = shost_to_rport(shost); 609 610 pr_debug("timeout for sdev %s\n", dev_name(&sdev->sdev_gendev)); 611 return rport && rport->fast_io_fail_tmo < 0 && 612 rport->dev_loss_tmo < 0 && 613 i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ? 614 SCSI_EH_RESET_TIMER : SCSI_EH_NOT_HANDLED; 615} 616EXPORT_SYMBOL(srp_timed_out); 617 618static void srp_rport_release(struct device *dev) 619{ 620 struct srp_rport *rport = dev_to_rport(dev); 621 622 put_device(dev->parent); 623 kfree(rport); 624} 625 626static int scsi_is_srp_rport(const struct device *dev) 627{ 628 return dev->release == srp_rport_release; 629} 630 631static int srp_rport_match(struct attribute_container *cont, 632 struct device *dev) 633{ 634 struct Scsi_Host *shost; 635 struct srp_internal *i; 636 637 if (!scsi_is_srp_rport(dev)) 638 return 0; 639 640 shost = dev_to_shost(dev->parent); 641 if (!shost->transportt) 642 return 0; 643 if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) 644 return 0; 645 646 i = to_srp_internal(shost->transportt); 647 return &i->rport_attr_cont.ac == cont; 648} 649 650static int srp_host_match(struct attribute_container *cont, struct device *dev) 651{ 652 struct Scsi_Host *shost; 653 struct srp_internal *i; 654 655 if (!scsi_is_host_device(dev)) 656 return 0; 657 658 shost = dev_to_shost(dev); 659 if (!shost->transportt) 660 return 0; 661 if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) 662 return 0; 663 664 i = to_srp_internal(shost->transportt); 665 return &i->t.host_attrs.ac == cont; 666} 667 668/** 669 * srp_rport_get() - increment rport reference count 670 * @rport: SRP target port. 671 */ 672void srp_rport_get(struct srp_rport *rport) 673{ 674 get_device(&rport->dev); 675} 676EXPORT_SYMBOL(srp_rport_get); 677 678/** 679 * srp_rport_put() - decrement rport reference count 680 * @rport: SRP target port. 681 */ 682void srp_rport_put(struct srp_rport *rport) 683{ 684 put_device(&rport->dev); 685} 686EXPORT_SYMBOL(srp_rport_put); 687 688/** 689 * srp_rport_add - add a SRP remote port to the device hierarchy 690 * @shost: scsi host the remote port is connected to. 691 * @ids: The port id for the remote port. 692 * 693 * Publishes a port to the rest of the system. 694 */ 695struct srp_rport *srp_rport_add(struct Scsi_Host *shost, 696 struct srp_rport_identifiers *ids) 697{ 698 struct srp_rport *rport; 699 struct device *parent = &shost->shost_gendev; 700 struct srp_internal *i = to_srp_internal(shost->transportt); 701 int id, ret; 702 703 rport = kzalloc(sizeof(*rport), GFP_KERNEL); 704 if (!rport) 705 return ERR_PTR(-ENOMEM); 706 707 mutex_init(&rport->mutex); 708 709 device_initialize(&rport->dev); 710 711 rport->dev.parent = get_device(parent); 712 rport->dev.release = srp_rport_release; 713 714 memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id)); 715 rport->roles = ids->roles; 716 717 if (i->f->reconnect) 718 rport->reconnect_delay = i->f->reconnect_delay ? 719 *i->f->reconnect_delay : 10; 720 INIT_DELAYED_WORK(&rport->reconnect_work, srp_reconnect_work); 721 rport->fast_io_fail_tmo = i->f->fast_io_fail_tmo ? 722 *i->f->fast_io_fail_tmo : 15; 723 rport->dev_loss_tmo = i->f->dev_loss_tmo ? *i->f->dev_loss_tmo : 60; 724 INIT_DELAYED_WORK(&rport->fast_io_fail_work, 725 rport_fast_io_fail_timedout); 726 INIT_DELAYED_WORK(&rport->dev_loss_work, rport_dev_loss_timedout); 727 728 id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id); 729 dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id); 730 731 transport_setup_device(&rport->dev); 732 733 ret = device_add(&rport->dev); 734 if (ret) { 735 transport_destroy_device(&rport->dev); 736 put_device(&rport->dev); 737 return ERR_PTR(ret); 738 } 739 740 transport_add_device(&rport->dev); 741 transport_configure_device(&rport->dev); 742 743 return rport; 744} 745EXPORT_SYMBOL_GPL(srp_rport_add); 746 747/** 748 * srp_rport_del - remove a SRP remote port 749 * @rport: SRP remote port to remove 750 * 751 * Removes the specified SRP remote port. 752 */ 753void srp_rport_del(struct srp_rport *rport) 754{ 755 struct device *dev = &rport->dev; 756 757 transport_remove_device(dev); 758 device_del(dev); 759 transport_destroy_device(dev); 760 761 put_device(dev); 762} 763EXPORT_SYMBOL_GPL(srp_rport_del); 764 765static int do_srp_rport_del(struct device *dev, void *data) 766{ 767 if (scsi_is_srp_rport(dev)) 768 srp_rport_del(dev_to_rport(dev)); 769 return 0; 770} 771 772/** 773 * srp_remove_host - tear down a Scsi_Host's SRP data structures 774 * @shost: Scsi Host that is torn down 775 * 776 * Removes all SRP remote ports for a given Scsi_Host. 777 * Must be called just before scsi_remove_host for SRP HBAs. 778 */ 779void srp_remove_host(struct Scsi_Host *shost) 780{ 781 device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del); 782} 783EXPORT_SYMBOL_GPL(srp_remove_host); 784 785/** 786 * srp_stop_rport_timers - stop the transport layer recovery timers 787 * @rport: SRP remote port for which to stop the timers. 788 * 789 * Must be called after srp_remove_host() and scsi_remove_host(). The caller 790 * must hold a reference on the rport (rport->dev) and on the SCSI host 791 * (rport->dev.parent). 792 */ 793void srp_stop_rport_timers(struct srp_rport *rport) 794{ 795 mutex_lock(&rport->mutex); 796 if (rport->state == SRP_RPORT_BLOCKED) 797 __rport_fail_io_fast(rport); 798 srp_rport_set_state(rport, SRP_RPORT_LOST); 799 mutex_unlock(&rport->mutex); 800 801 cancel_delayed_work_sync(&rport->reconnect_work); 802 cancel_delayed_work_sync(&rport->fast_io_fail_work); 803 cancel_delayed_work_sync(&rport->dev_loss_work); 804} 805EXPORT_SYMBOL_GPL(srp_stop_rport_timers); 806 807/** 808 * srp_attach_transport - instantiate SRP transport template 809 * @ft: SRP transport class function template 810 */ 811struct scsi_transport_template * 812srp_attach_transport(struct srp_function_template *ft) 813{ 814 int count; 815 struct srp_internal *i; 816 817 i = kzalloc(sizeof(*i), GFP_KERNEL); 818 if (!i) 819 return NULL; 820 821 i->t.host_size = sizeof(struct srp_host_attrs); 822 i->t.host_attrs.ac.attrs = &i->host_attrs[0]; 823 i->t.host_attrs.ac.class = &srp_host_class.class; 824 i->t.host_attrs.ac.match = srp_host_match; 825 i->host_attrs[0] = NULL; 826 transport_container_register(&i->t.host_attrs); 827 828 i->rport_attr_cont.ac.attrs = &i->rport_attrs[0]; 829 i->rport_attr_cont.ac.class = &srp_rport_class.class; 830 i->rport_attr_cont.ac.match = srp_rport_match; 831 832 count = 0; 833 i->rport_attrs[count++] = &dev_attr_port_id; 834 i->rport_attrs[count++] = &dev_attr_roles; 835 if (ft->has_rport_state) { 836 i->rport_attrs[count++] = &dev_attr_state; 837 i->rport_attrs[count++] = &dev_attr_fast_io_fail_tmo; 838 i->rport_attrs[count++] = &dev_attr_dev_loss_tmo; 839 } 840 if (ft->reconnect) { 841 i->rport_attrs[count++] = &dev_attr_reconnect_delay; 842 i->rport_attrs[count++] = &dev_attr_failed_reconnects; 843 } 844 if (ft->rport_delete) 845 i->rport_attrs[count++] = &dev_attr_delete; 846 i->rport_attrs[count++] = NULL; 847 BUG_ON(count > ARRAY_SIZE(i->rport_attrs)); 848 849 transport_container_register(&i->rport_attr_cont); 850 851 i->f = ft; 852 853 return &i->t; 854} 855EXPORT_SYMBOL_GPL(srp_attach_transport); 856 857/** 858 * srp_release_transport - release SRP transport template instance 859 * @t: transport template instance 860 */ 861void srp_release_transport(struct scsi_transport_template *t) 862{ 863 struct srp_internal *i = to_srp_internal(t); 864 865 transport_container_unregister(&i->t.host_attrs); 866 transport_container_unregister(&i->rport_attr_cont); 867 868 kfree(i); 869} 870EXPORT_SYMBOL_GPL(srp_release_transport); 871 872static __init int srp_transport_init(void) 873{ 874 int ret; 875 876 ret = transport_class_register(&srp_host_class); 877 if (ret) 878 return ret; 879 ret = transport_class_register(&srp_rport_class); 880 if (ret) 881 goto unregister_host_class; 882 883 return 0; 884unregister_host_class: 885 transport_class_unregister(&srp_host_class); 886 return ret; 887} 888 889static void __exit srp_transport_exit(void) 890{ 891 transport_class_unregister(&srp_host_class); 892 transport_class_unregister(&srp_rport_class); 893} 894 895MODULE_AUTHOR("FUJITA Tomonori"); 896MODULE_DESCRIPTION("SRP Transport Attributes"); 897MODULE_LICENSE("GPL"); 898 899module_init(srp_transport_init); 900module_exit(srp_transport_exit); 901