1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2017-2018 Christoph Hellwig. 4 */ 5 6 #include <linux/backing-dev.h> 7 #include <linux/moduleparam.h> 8 #include <linux/vmalloc.h> 9 #include <trace/events/block.h> 10 #include "nvme.h" 11 12 bool multipath = true; 13 module_param(multipath, bool, 0444); 14 MODULE_PARM_DESC(multipath, 15 "turn on native support for multiple controllers per subsystem"); 16 17 static const char *nvme_iopolicy_names[] = { 18 [NVME_IOPOLICY_NUMA] = "numa", 19 [NVME_IOPOLICY_RR] = "round-robin", 20 }; 21 22 static int iopolicy = NVME_IOPOLICY_NUMA; 23 24 static int nvme_set_iopolicy(const char *val, const struct kernel_param *kp) 25 { 26 if (!val) 27 return -EINVAL; 28 if (!strncmp(val, "numa", 4)) 29 iopolicy = NVME_IOPOLICY_NUMA; 30 else if (!strncmp(val, "round-robin", 11)) 31 iopolicy = NVME_IOPOLICY_RR; 32 else 33 return -EINVAL; 34 35 return 0; 36 } 37 38 static int nvme_get_iopolicy(char *buf, const struct kernel_param *kp) 39 { 40 return sprintf(buf, "%s\n", nvme_iopolicy_names[iopolicy]); 41 } 42 43 module_param_call(iopolicy, nvme_set_iopolicy, nvme_get_iopolicy, 44 &iopolicy, 0644); 45 MODULE_PARM_DESC(iopolicy, 46 "Default multipath I/O policy; 'numa' (default) or 'round-robin'"); 47 48 void nvme_mpath_default_iopolicy(struct nvme_subsystem *subsys) 49 { 50 subsys->iopolicy = iopolicy; 51 } 52 53 void nvme_mpath_unfreeze(struct nvme_subsystem *subsys) 54 { 55 struct nvme_ns_head *h; 56 57 lockdep_assert_held(&subsys->lock); 58 list_for_each_entry(h, &subsys->nsheads, entry) 59 if (h->disk) 60 blk_mq_unfreeze_queue(h->disk->queue); 61 } 62 63 void nvme_mpath_wait_freeze(struct nvme_subsystem *subsys) 64 { 65 struct nvme_ns_head *h; 66 67 lockdep_assert_held(&subsys->lock); 68 list_for_each_entry(h, &subsys->nsheads, entry) 69 if (h->disk) 70 blk_mq_freeze_queue_wait(h->disk->queue); 71 } 72 73 void nvme_mpath_start_freeze(struct nvme_subsystem *subsys) 74 { 75 struct nvme_ns_head *h; 76 77 lockdep_assert_held(&subsys->lock); 78 list_for_each_entry(h, &subsys->nsheads, entry) 79 if (h->disk) 80 blk_freeze_queue_start(h->disk->queue); 81 } 82 83 void nvme_failover_req(struct request *req) 84 { 85 struct nvme_ns *ns = req->q->queuedata; 86 u16 status = nvme_req(req)->status & 0x7ff; 87 unsigned long flags; 88 struct bio *bio; 89 90 nvme_mpath_clear_current_path(ns); 91 92 /* 93 * If we got back an ANA error, we know the controller is alive but not 94 * ready to serve this namespace. Kick of a re-read of the ANA 95 * information page, and just try any other available path for now. 96 */ 97 if (nvme_is_ana_error(status) && ns->ctrl->ana_log_buf) { 98 set_bit(NVME_NS_ANA_PENDING, &ns->flags); 99 queue_work(nvme_wq, &ns->ctrl->ana_work); 100 } 101 102 spin_lock_irqsave(&ns->head->requeue_lock, flags); 103 for (bio = req->bio; bio; bio = bio->bi_next) { 104 bio_set_dev(bio, ns->head->disk->part0); 105 if (bio->bi_opf & REQ_POLLED) { 106 bio->bi_opf &= ~REQ_POLLED; 107 bio->bi_cookie = BLK_QC_T_NONE; 108 } 109 } 110 blk_steal_bios(&ns->head->requeue_list, req); 111 spin_unlock_irqrestore(&ns->head->requeue_lock, flags); 112 113 blk_mq_end_request(req, 0); 114 kblockd_schedule_work(&ns->head->requeue_work); 115 } 116 117 void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl) 118 { 119 struct nvme_ns *ns; 120 121 down_read(&ctrl->namespaces_rwsem); 122 list_for_each_entry(ns, &ctrl->namespaces, list) { 123 if (!ns->head->disk) 124 continue; 125 kblockd_schedule_work(&ns->head->requeue_work); 126 if (ctrl->state == NVME_CTRL_LIVE) 127 disk_uevent(ns->head->disk, KOBJ_CHANGE); 128 } 129 up_read(&ctrl->namespaces_rwsem); 130 } 131 132 static const char *nvme_ana_state_names[] = { 133 [0] = "invalid state", 134 [NVME_ANA_OPTIMIZED] = "optimized", 135 [NVME_ANA_NONOPTIMIZED] = "non-optimized", 136 [NVME_ANA_INACCESSIBLE] = "inaccessible", 137 [NVME_ANA_PERSISTENT_LOSS] = "persistent-loss", 138 [NVME_ANA_CHANGE] = "change", 139 }; 140 141 bool nvme_mpath_clear_current_path(struct nvme_ns *ns) 142 { 143 struct nvme_ns_head *head = ns->head; 144 bool changed = false; 145 int node; 146 147 if (!head) 148 goto out; 149 150 for_each_node(node) { 151 if (ns == rcu_access_pointer(head->current_path[node])) { 152 rcu_assign_pointer(head->current_path[node], NULL); 153 changed = true; 154 } 155 } 156 out: 157 return changed; 158 } 159 160 void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl) 161 { 162 struct nvme_ns *ns; 163 164 down_read(&ctrl->namespaces_rwsem); 165 list_for_each_entry(ns, &ctrl->namespaces, list) { 166 nvme_mpath_clear_current_path(ns); 167 kblockd_schedule_work(&ns->head->requeue_work); 168 } 169 up_read(&ctrl->namespaces_rwsem); 170 } 171 172 void nvme_mpath_revalidate_paths(struct nvme_ns *ns) 173 { 174 struct nvme_ns_head *head = ns->head; 175 sector_t capacity = get_capacity(head->disk); 176 int node; 177 178 list_for_each_entry_rcu(ns, &head->list, siblings) { 179 if (capacity != get_capacity(ns->disk)) 180 clear_bit(NVME_NS_READY, &ns->flags); 181 } 182 183 for_each_node(node) 184 rcu_assign_pointer(head->current_path[node], NULL); 185 } 186 187 static bool nvme_path_is_disabled(struct nvme_ns *ns) 188 { 189 /* 190 * We don't treat NVME_CTRL_DELETING as a disabled path as I/O should 191 * still be able to complete assuming that the controller is connected. 192 * Otherwise it will fail immediately and return to the requeue list. 193 */ 194 if (ns->ctrl->state != NVME_CTRL_LIVE && 195 ns->ctrl->state != NVME_CTRL_DELETING) 196 return true; 197 if (test_bit(NVME_NS_ANA_PENDING, &ns->flags) || 198 !test_bit(NVME_NS_READY, &ns->flags)) 199 return true; 200 return false; 201 } 202 203 static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head, int node) 204 { 205 int found_distance = INT_MAX, fallback_distance = INT_MAX, distance; 206 struct nvme_ns *found = NULL, *fallback = NULL, *ns; 207 208 list_for_each_entry_rcu(ns, &head->list, siblings) { 209 if (nvme_path_is_disabled(ns)) 210 continue; 211 212 if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_NUMA) 213 distance = node_distance(node, ns->ctrl->numa_node); 214 else 215 distance = LOCAL_DISTANCE; 216 217 switch (ns->ana_state) { 218 case NVME_ANA_OPTIMIZED: 219 if (distance < found_distance) { 220 found_distance = distance; 221 found = ns; 222 } 223 break; 224 case NVME_ANA_NONOPTIMIZED: 225 if (distance < fallback_distance) { 226 fallback_distance = distance; 227 fallback = ns; 228 } 229 break; 230 default: 231 break; 232 } 233 } 234 235 if (!found) 236 found = fallback; 237 if (found) 238 rcu_assign_pointer(head->current_path[node], found); 239 return found; 240 } 241 242 static struct nvme_ns *nvme_next_ns(struct nvme_ns_head *head, 243 struct nvme_ns *ns) 244 { 245 ns = list_next_or_null_rcu(&head->list, &ns->siblings, struct nvme_ns, 246 siblings); 247 if (ns) 248 return ns; 249 return list_first_or_null_rcu(&head->list, struct nvme_ns, siblings); 250 } 251 252 static struct nvme_ns *nvme_round_robin_path(struct nvme_ns_head *head, 253 int node, struct nvme_ns *old) 254 { 255 struct nvme_ns *ns, *found = NULL; 256 257 if (list_is_singular(&head->list)) { 258 if (nvme_path_is_disabled(old)) 259 return NULL; 260 return old; 261 } 262 263 for (ns = nvme_next_ns(head, old); 264 ns && ns != old; 265 ns = nvme_next_ns(head, ns)) { 266 if (nvme_path_is_disabled(ns)) 267 continue; 268 269 if (ns->ana_state == NVME_ANA_OPTIMIZED) { 270 found = ns; 271 goto out; 272 } 273 if (ns->ana_state == NVME_ANA_NONOPTIMIZED) 274 found = ns; 275 } 276 277 /* 278 * The loop above skips the current path for round-robin semantics. 279 * Fall back to the current path if either: 280 * - no other optimized path found and current is optimized, 281 * - no other usable path found and current is usable. 282 */ 283 if (!nvme_path_is_disabled(old) && 284 (old->ana_state == NVME_ANA_OPTIMIZED || 285 (!found && old->ana_state == NVME_ANA_NONOPTIMIZED))) 286 return old; 287 288 if (!found) 289 return NULL; 290 out: 291 rcu_assign_pointer(head->current_path[node], found); 292 return found; 293 } 294 295 static inline bool nvme_path_is_optimized(struct nvme_ns *ns) 296 { 297 return ns->ctrl->state == NVME_CTRL_LIVE && 298 ns->ana_state == NVME_ANA_OPTIMIZED; 299 } 300 301 inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head) 302 { 303 int node = numa_node_id(); 304 struct nvme_ns *ns; 305 306 ns = srcu_dereference(head->current_path[node], &head->srcu); 307 if (unlikely(!ns)) 308 return __nvme_find_path(head, node); 309 310 if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_RR) 311 return nvme_round_robin_path(head, node, ns); 312 if (unlikely(!nvme_path_is_optimized(ns))) 313 return __nvme_find_path(head, node); 314 return ns; 315 } 316 317 static bool nvme_available_path(struct nvme_ns_head *head) 318 { 319 struct nvme_ns *ns; 320 321 list_for_each_entry_rcu(ns, &head->list, siblings) { 322 if (test_bit(NVME_CTRL_FAILFAST_EXPIRED, &ns->ctrl->flags)) 323 continue; 324 switch (ns->ctrl->state) { 325 case NVME_CTRL_LIVE: 326 case NVME_CTRL_RESETTING: 327 case NVME_CTRL_CONNECTING: 328 /* fallthru */ 329 return true; 330 default: 331 break; 332 } 333 } 334 return false; 335 } 336 337 static void nvme_ns_head_submit_bio(struct bio *bio) 338 { 339 struct nvme_ns_head *head = bio->bi_bdev->bd_disk->private_data; 340 struct device *dev = disk_to_dev(head->disk); 341 struct nvme_ns *ns; 342 int srcu_idx; 343 344 /* 345 * The namespace might be going away and the bio might be moved to a 346 * different queue via blk_steal_bios(), so we need to use the bio_split 347 * pool from the original queue to allocate the bvecs from. 348 */ 349 blk_queue_split(&bio); 350 351 srcu_idx = srcu_read_lock(&head->srcu); 352 ns = nvme_find_path(head); 353 if (likely(ns)) { 354 bio_set_dev(bio, ns->disk->part0); 355 bio->bi_opf |= REQ_NVME_MPATH; 356 trace_block_bio_remap(bio, disk_devt(ns->head->disk), 357 bio->bi_iter.bi_sector); 358 submit_bio_noacct(bio); 359 } else if (nvme_available_path(head)) { 360 dev_warn_ratelimited(dev, "no usable path - requeuing I/O\n"); 361 362 spin_lock_irq(&head->requeue_lock); 363 bio_list_add(&head->requeue_list, bio); 364 spin_unlock_irq(&head->requeue_lock); 365 } else { 366 dev_warn_ratelimited(dev, "no available path - failing I/O\n"); 367 368 bio_io_error(bio); 369 } 370 371 srcu_read_unlock(&head->srcu, srcu_idx); 372 } 373 374 static int nvme_ns_head_open(struct block_device *bdev, fmode_t mode) 375 { 376 if (!nvme_tryget_ns_head(bdev->bd_disk->private_data)) 377 return -ENXIO; 378 return 0; 379 } 380 381 static void nvme_ns_head_release(struct gendisk *disk, fmode_t mode) 382 { 383 nvme_put_ns_head(disk->private_data); 384 } 385 386 #ifdef CONFIG_BLK_DEV_ZONED 387 static int nvme_ns_head_report_zones(struct gendisk *disk, sector_t sector, 388 unsigned int nr_zones, report_zones_cb cb, void *data) 389 { 390 struct nvme_ns_head *head = disk->private_data; 391 struct nvme_ns *ns; 392 int srcu_idx, ret = -EWOULDBLOCK; 393 394 srcu_idx = srcu_read_lock(&head->srcu); 395 ns = nvme_find_path(head); 396 if (ns) 397 ret = nvme_ns_report_zones(ns, sector, nr_zones, cb, data); 398 srcu_read_unlock(&head->srcu, srcu_idx); 399 return ret; 400 } 401 #else 402 #define nvme_ns_head_report_zones NULL 403 #endif /* CONFIG_BLK_DEV_ZONED */ 404 405 const struct block_device_operations nvme_ns_head_ops = { 406 .owner = THIS_MODULE, 407 .submit_bio = nvme_ns_head_submit_bio, 408 .open = nvme_ns_head_open, 409 .release = nvme_ns_head_release, 410 .ioctl = nvme_ns_head_ioctl, 411 .getgeo = nvme_getgeo, 412 .report_zones = nvme_ns_head_report_zones, 413 .pr_ops = &nvme_pr_ops, 414 }; 415 416 static inline struct nvme_ns_head *cdev_to_ns_head(struct cdev *cdev) 417 { 418 return container_of(cdev, struct nvme_ns_head, cdev); 419 } 420 421 static int nvme_ns_head_chr_open(struct inode *inode, struct file *file) 422 { 423 if (!nvme_tryget_ns_head(cdev_to_ns_head(inode->i_cdev))) 424 return -ENXIO; 425 return 0; 426 } 427 428 static int nvme_ns_head_chr_release(struct inode *inode, struct file *file) 429 { 430 nvme_put_ns_head(cdev_to_ns_head(inode->i_cdev)); 431 return 0; 432 } 433 434 static const struct file_operations nvme_ns_head_chr_fops = { 435 .owner = THIS_MODULE, 436 .open = nvme_ns_head_chr_open, 437 .release = nvme_ns_head_chr_release, 438 .unlocked_ioctl = nvme_ns_head_chr_ioctl, 439 .compat_ioctl = compat_ptr_ioctl, 440 }; 441 442 static int nvme_add_ns_head_cdev(struct nvme_ns_head *head) 443 { 444 int ret; 445 446 head->cdev_device.parent = &head->subsys->dev; 447 ret = dev_set_name(&head->cdev_device, "ng%dn%d", 448 head->subsys->instance, head->instance); 449 if (ret) 450 return ret; 451 ret = nvme_cdev_add(&head->cdev, &head->cdev_device, 452 &nvme_ns_head_chr_fops, THIS_MODULE); 453 return ret; 454 } 455 456 static void nvme_requeue_work(struct work_struct *work) 457 { 458 struct nvme_ns_head *head = 459 container_of(work, struct nvme_ns_head, requeue_work); 460 struct bio *bio, *next; 461 462 spin_lock_irq(&head->requeue_lock); 463 next = bio_list_get(&head->requeue_list); 464 spin_unlock_irq(&head->requeue_lock); 465 466 while ((bio = next) != NULL) { 467 next = bio->bi_next; 468 bio->bi_next = NULL; 469 470 submit_bio_noacct(bio); 471 } 472 } 473 474 int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) 475 { 476 bool vwc = false; 477 478 mutex_init(&head->lock); 479 bio_list_init(&head->requeue_list); 480 spin_lock_init(&head->requeue_lock); 481 INIT_WORK(&head->requeue_work, nvme_requeue_work); 482 483 /* 484 * Add a multipath node if the subsystems supports multiple controllers. 485 * We also do this for private namespaces as the namespace sharing flag 486 * could change after a rescan. 487 */ 488 if (!(ctrl->subsys->cmic & NVME_CTRL_CMIC_MULTI_CTRL) || 489 !nvme_is_unique_nsid(ctrl, head) || !multipath) 490 return 0; 491 492 head->disk = blk_alloc_disk(ctrl->numa_node); 493 if (!head->disk) 494 return -ENOMEM; 495 head->disk->fops = &nvme_ns_head_ops; 496 head->disk->private_data = head; 497 sprintf(head->disk->disk_name, "nvme%dn%d", 498 ctrl->subsys->instance, head->instance); 499 500 blk_queue_flag_set(QUEUE_FLAG_NONROT, head->disk->queue); 501 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, head->disk->queue); 502 /* 503 * This assumes all controllers that refer to a namespace either 504 * support poll queues or not. That is not a strict guarantee, 505 * but if the assumption is wrong the effect is only suboptimal 506 * performance but not correctness problem. 507 */ 508 if (ctrl->tagset->nr_maps > HCTX_TYPE_POLL && 509 ctrl->tagset->map[HCTX_TYPE_POLL].nr_queues) 510 blk_queue_flag_set(QUEUE_FLAG_POLL, head->disk->queue); 511 512 /* set to a default value of 512 until the disk is validated */ 513 blk_queue_logical_block_size(head->disk->queue, 512); 514 blk_set_stacking_limits(&head->disk->queue->limits); 515 516 /* we need to propagate up the VMC settings */ 517 if (ctrl->vwc & NVME_CTRL_VWC_PRESENT) 518 vwc = true; 519 blk_queue_write_cache(head->disk->queue, vwc, vwc); 520 return 0; 521 } 522 523 static void nvme_mpath_set_live(struct nvme_ns *ns) 524 { 525 struct nvme_ns_head *head = ns->head; 526 int rc; 527 528 if (!head->disk) 529 return; 530 531 /* 532 * test_and_set_bit() is used because it is protecting against two nvme 533 * paths simultaneously calling device_add_disk() on the same namespace 534 * head. 535 */ 536 if (!test_and_set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { 537 rc = device_add_disk(&head->subsys->dev, head->disk, 538 nvme_ns_id_attr_groups); 539 if (rc) { 540 clear_bit(NVME_NSHEAD_DISK_LIVE, &ns->flags); 541 return; 542 } 543 nvme_add_ns_head_cdev(head); 544 } 545 546 mutex_lock(&head->lock); 547 if (nvme_path_is_optimized(ns)) { 548 int node, srcu_idx; 549 550 srcu_idx = srcu_read_lock(&head->srcu); 551 for_each_node(node) 552 __nvme_find_path(head, node); 553 srcu_read_unlock(&head->srcu, srcu_idx); 554 } 555 mutex_unlock(&head->lock); 556 557 synchronize_srcu(&head->srcu); 558 kblockd_schedule_work(&head->requeue_work); 559 } 560 561 static int nvme_parse_ana_log(struct nvme_ctrl *ctrl, void *data, 562 int (*cb)(struct nvme_ctrl *ctrl, struct nvme_ana_group_desc *, 563 void *)) 564 { 565 void *base = ctrl->ana_log_buf; 566 size_t offset = sizeof(struct nvme_ana_rsp_hdr); 567 int error, i; 568 569 lockdep_assert_held(&ctrl->ana_lock); 570 571 for (i = 0; i < le16_to_cpu(ctrl->ana_log_buf->ngrps); i++) { 572 struct nvme_ana_group_desc *desc = base + offset; 573 u32 nr_nsids; 574 size_t nsid_buf_size; 575 576 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - sizeof(*desc))) 577 return -EINVAL; 578 579 nr_nsids = le32_to_cpu(desc->nnsids); 580 nsid_buf_size = flex_array_size(desc, nsids, nr_nsids); 581 582 if (WARN_ON_ONCE(desc->grpid == 0)) 583 return -EINVAL; 584 if (WARN_ON_ONCE(le32_to_cpu(desc->grpid) > ctrl->anagrpmax)) 585 return -EINVAL; 586 if (WARN_ON_ONCE(desc->state == 0)) 587 return -EINVAL; 588 if (WARN_ON_ONCE(desc->state > NVME_ANA_CHANGE)) 589 return -EINVAL; 590 591 offset += sizeof(*desc); 592 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - nsid_buf_size)) 593 return -EINVAL; 594 595 error = cb(ctrl, desc, data); 596 if (error) 597 return error; 598 599 offset += nsid_buf_size; 600 } 601 602 return 0; 603 } 604 605 static inline bool nvme_state_is_live(enum nvme_ana_state state) 606 { 607 return state == NVME_ANA_OPTIMIZED || state == NVME_ANA_NONOPTIMIZED; 608 } 609 610 static void nvme_update_ns_ana_state(struct nvme_ana_group_desc *desc, 611 struct nvme_ns *ns) 612 { 613 ns->ana_grpid = le32_to_cpu(desc->grpid); 614 ns->ana_state = desc->state; 615 clear_bit(NVME_NS_ANA_PENDING, &ns->flags); 616 /* 617 * nvme_mpath_set_live() will trigger I/O to the multipath path device 618 * and in turn to this path device. However we cannot accept this I/O 619 * if the controller is not live. This may deadlock if called from 620 * nvme_mpath_init_identify() and the ctrl will never complete 621 * initialization, preventing I/O from completing. For this case we 622 * will reprocess the ANA log page in nvme_mpath_update() once the 623 * controller is ready. 624 */ 625 if (nvme_state_is_live(ns->ana_state) && 626 ns->ctrl->state == NVME_CTRL_LIVE) 627 nvme_mpath_set_live(ns); 628 } 629 630 static int nvme_update_ana_state(struct nvme_ctrl *ctrl, 631 struct nvme_ana_group_desc *desc, void *data) 632 { 633 u32 nr_nsids = le32_to_cpu(desc->nnsids), n = 0; 634 unsigned *nr_change_groups = data; 635 struct nvme_ns *ns; 636 637 dev_dbg(ctrl->device, "ANA group %d: %s.\n", 638 le32_to_cpu(desc->grpid), 639 nvme_ana_state_names[desc->state]); 640 641 if (desc->state == NVME_ANA_CHANGE) 642 (*nr_change_groups)++; 643 644 if (!nr_nsids) 645 return 0; 646 647 down_read(&ctrl->namespaces_rwsem); 648 list_for_each_entry(ns, &ctrl->namespaces, list) { 649 unsigned nsid; 650 again: 651 nsid = le32_to_cpu(desc->nsids[n]); 652 if (ns->head->ns_id < nsid) 653 continue; 654 if (ns->head->ns_id == nsid) 655 nvme_update_ns_ana_state(desc, ns); 656 if (++n == nr_nsids) 657 break; 658 if (ns->head->ns_id > nsid) 659 goto again; 660 } 661 up_read(&ctrl->namespaces_rwsem); 662 return 0; 663 } 664 665 static int nvme_read_ana_log(struct nvme_ctrl *ctrl) 666 { 667 u32 nr_change_groups = 0; 668 int error; 669 670 mutex_lock(&ctrl->ana_lock); 671 error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_ANA, 0, NVME_CSI_NVM, 672 ctrl->ana_log_buf, ctrl->ana_log_size, 0); 673 if (error) { 674 dev_warn(ctrl->device, "Failed to get ANA log: %d\n", error); 675 goto out_unlock; 676 } 677 678 error = nvme_parse_ana_log(ctrl, &nr_change_groups, 679 nvme_update_ana_state); 680 if (error) 681 goto out_unlock; 682 683 /* 684 * In theory we should have an ANATT timer per group as they might enter 685 * the change state at different times. But that is a lot of overhead 686 * just to protect against a target that keeps entering new changes 687 * states while never finishing previous ones. But we'll still 688 * eventually time out once all groups are in change state, so this 689 * isn't a big deal. 690 * 691 * We also double the ANATT value to provide some slack for transports 692 * or AEN processing overhead. 693 */ 694 if (nr_change_groups) 695 mod_timer(&ctrl->anatt_timer, ctrl->anatt * HZ * 2 + jiffies); 696 else 697 del_timer_sync(&ctrl->anatt_timer); 698 out_unlock: 699 mutex_unlock(&ctrl->ana_lock); 700 return error; 701 } 702 703 static void nvme_ana_work(struct work_struct *work) 704 { 705 struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ana_work); 706 707 if (ctrl->state != NVME_CTRL_LIVE) 708 return; 709 710 nvme_read_ana_log(ctrl); 711 } 712 713 void nvme_mpath_update(struct nvme_ctrl *ctrl) 714 { 715 u32 nr_change_groups = 0; 716 717 if (!ctrl->ana_log_buf) 718 return; 719 720 mutex_lock(&ctrl->ana_lock); 721 nvme_parse_ana_log(ctrl, &nr_change_groups, nvme_update_ana_state); 722 mutex_unlock(&ctrl->ana_lock); 723 } 724 725 static void nvme_anatt_timeout(struct timer_list *t) 726 { 727 struct nvme_ctrl *ctrl = from_timer(ctrl, t, anatt_timer); 728 729 dev_info(ctrl->device, "ANATT timeout, resetting controller.\n"); 730 nvme_reset_ctrl(ctrl); 731 } 732 733 void nvme_mpath_stop(struct nvme_ctrl *ctrl) 734 { 735 if (!nvme_ctrl_use_ana(ctrl)) 736 return; 737 del_timer_sync(&ctrl->anatt_timer); 738 cancel_work_sync(&ctrl->ana_work); 739 } 740 741 #define SUBSYS_ATTR_RW(_name, _mode, _show, _store) \ 742 struct device_attribute subsys_attr_##_name = \ 743 __ATTR(_name, _mode, _show, _store) 744 745 static ssize_t nvme_subsys_iopolicy_show(struct device *dev, 746 struct device_attribute *attr, char *buf) 747 { 748 struct nvme_subsystem *subsys = 749 container_of(dev, struct nvme_subsystem, dev); 750 751 return sysfs_emit(buf, "%s\n", 752 nvme_iopolicy_names[READ_ONCE(subsys->iopolicy)]); 753 } 754 755 static ssize_t nvme_subsys_iopolicy_store(struct device *dev, 756 struct device_attribute *attr, const char *buf, size_t count) 757 { 758 struct nvme_subsystem *subsys = 759 container_of(dev, struct nvme_subsystem, dev); 760 int i; 761 762 for (i = 0; i < ARRAY_SIZE(nvme_iopolicy_names); i++) { 763 if (sysfs_streq(buf, nvme_iopolicy_names[i])) { 764 WRITE_ONCE(subsys->iopolicy, i); 765 return count; 766 } 767 } 768 769 return -EINVAL; 770 } 771 SUBSYS_ATTR_RW(iopolicy, S_IRUGO | S_IWUSR, 772 nvme_subsys_iopolicy_show, nvme_subsys_iopolicy_store); 773 774 static ssize_t ana_grpid_show(struct device *dev, struct device_attribute *attr, 775 char *buf) 776 { 777 return sysfs_emit(buf, "%d\n", nvme_get_ns_from_dev(dev)->ana_grpid); 778 } 779 DEVICE_ATTR_RO(ana_grpid); 780 781 static ssize_t ana_state_show(struct device *dev, struct device_attribute *attr, 782 char *buf) 783 { 784 struct nvme_ns *ns = nvme_get_ns_from_dev(dev); 785 786 return sysfs_emit(buf, "%s\n", nvme_ana_state_names[ns->ana_state]); 787 } 788 DEVICE_ATTR_RO(ana_state); 789 790 static int nvme_lookup_ana_group_desc(struct nvme_ctrl *ctrl, 791 struct nvme_ana_group_desc *desc, void *data) 792 { 793 struct nvme_ana_group_desc *dst = data; 794 795 if (desc->grpid != dst->grpid) 796 return 0; 797 798 *dst = *desc; 799 return -ENXIO; /* just break out of the loop */ 800 } 801 802 void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id) 803 { 804 if (nvme_ctrl_use_ana(ns->ctrl)) { 805 struct nvme_ana_group_desc desc = { 806 .grpid = id->anagrpid, 807 .state = 0, 808 }; 809 810 mutex_lock(&ns->ctrl->ana_lock); 811 ns->ana_grpid = le32_to_cpu(id->anagrpid); 812 nvme_parse_ana_log(ns->ctrl, &desc, nvme_lookup_ana_group_desc); 813 mutex_unlock(&ns->ctrl->ana_lock); 814 if (desc.state) { 815 /* found the group desc: update */ 816 nvme_update_ns_ana_state(&desc, ns); 817 } else { 818 /* group desc not found: trigger a re-read */ 819 set_bit(NVME_NS_ANA_PENDING, &ns->flags); 820 queue_work(nvme_wq, &ns->ctrl->ana_work); 821 } 822 } else { 823 ns->ana_state = NVME_ANA_OPTIMIZED; 824 nvme_mpath_set_live(ns); 825 } 826 827 if (blk_queue_stable_writes(ns->queue) && ns->head->disk) 828 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, 829 ns->head->disk->queue); 830 #ifdef CONFIG_BLK_DEV_ZONED 831 if (blk_queue_is_zoned(ns->queue) && ns->head->disk) 832 ns->head->disk->queue->nr_zones = ns->queue->nr_zones; 833 #endif 834 } 835 836 void nvme_mpath_shutdown_disk(struct nvme_ns_head *head) 837 { 838 if (!head->disk) 839 return; 840 kblockd_schedule_work(&head->requeue_work); 841 if (test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { 842 nvme_cdev_del(&head->cdev, &head->cdev_device); 843 del_gendisk(head->disk); 844 } 845 } 846 847 void nvme_mpath_remove_disk(struct nvme_ns_head *head) 848 { 849 if (!head->disk) 850 return; 851 blk_mark_disk_dead(head->disk); 852 /* make sure all pending bios are cleaned up */ 853 kblockd_schedule_work(&head->requeue_work); 854 flush_work(&head->requeue_work); 855 blk_cleanup_disk(head->disk); 856 } 857 858 void nvme_mpath_init_ctrl(struct nvme_ctrl *ctrl) 859 { 860 mutex_init(&ctrl->ana_lock); 861 timer_setup(&ctrl->anatt_timer, nvme_anatt_timeout, 0); 862 INIT_WORK(&ctrl->ana_work, nvme_ana_work); 863 } 864 865 int nvme_mpath_init_identify(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) 866 { 867 size_t max_transfer_size = ctrl->max_hw_sectors << SECTOR_SHIFT; 868 size_t ana_log_size; 869 int error = 0; 870 871 /* check if multipath is enabled and we have the capability */ 872 if (!multipath || !ctrl->subsys || 873 !(ctrl->subsys->cmic & NVME_CTRL_CMIC_ANA)) 874 return 0; 875 876 if (!ctrl->max_namespaces || 877 ctrl->max_namespaces > le32_to_cpu(id->nn)) { 878 dev_err(ctrl->device, 879 "Invalid MNAN value %u\n", ctrl->max_namespaces); 880 return -EINVAL; 881 } 882 883 ctrl->anacap = id->anacap; 884 ctrl->anatt = id->anatt; 885 ctrl->nanagrpid = le32_to_cpu(id->nanagrpid); 886 ctrl->anagrpmax = le32_to_cpu(id->anagrpmax); 887 888 ana_log_size = sizeof(struct nvme_ana_rsp_hdr) + 889 ctrl->nanagrpid * sizeof(struct nvme_ana_group_desc) + 890 ctrl->max_namespaces * sizeof(__le32); 891 if (ana_log_size > max_transfer_size) { 892 dev_err(ctrl->device, 893 "ANA log page size (%zd) larger than MDTS (%zd).\n", 894 ana_log_size, max_transfer_size); 895 dev_err(ctrl->device, "disabling ANA support.\n"); 896 goto out_uninit; 897 } 898 if (ana_log_size > ctrl->ana_log_size) { 899 nvme_mpath_stop(ctrl); 900 nvme_mpath_uninit(ctrl); 901 ctrl->ana_log_buf = kvmalloc(ana_log_size, GFP_KERNEL); 902 if (!ctrl->ana_log_buf) 903 return -ENOMEM; 904 } 905 ctrl->ana_log_size = ana_log_size; 906 error = nvme_read_ana_log(ctrl); 907 if (error) 908 goto out_uninit; 909 return 0; 910 911 out_uninit: 912 nvme_mpath_uninit(ctrl); 913 return error; 914 } 915 916 void nvme_mpath_uninit(struct nvme_ctrl *ctrl) 917 { 918 kvfree(ctrl->ana_log_buf); 919 ctrl->ana_log_buf = NULL; 920 ctrl->ana_log_size = 0; 921 } 922