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 bio = bio_split_to_limits(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 .compat_ioctl = blkdev_compat_ptr_ioctl, 412 .getgeo = nvme_getgeo, 413 .report_zones = nvme_ns_head_report_zones, 414 .pr_ops = &nvme_pr_ops, 415 }; 416 417 static inline struct nvme_ns_head *cdev_to_ns_head(struct cdev *cdev) 418 { 419 return container_of(cdev, struct nvme_ns_head, cdev); 420 } 421 422 static int nvme_ns_head_chr_open(struct inode *inode, struct file *file) 423 { 424 if (!nvme_tryget_ns_head(cdev_to_ns_head(inode->i_cdev))) 425 return -ENXIO; 426 return 0; 427 } 428 429 static int nvme_ns_head_chr_release(struct inode *inode, struct file *file) 430 { 431 nvme_put_ns_head(cdev_to_ns_head(inode->i_cdev)); 432 return 0; 433 } 434 435 static const struct file_operations nvme_ns_head_chr_fops = { 436 .owner = THIS_MODULE, 437 .open = nvme_ns_head_chr_open, 438 .release = nvme_ns_head_chr_release, 439 .unlocked_ioctl = nvme_ns_head_chr_ioctl, 440 .compat_ioctl = compat_ptr_ioctl, 441 .uring_cmd = nvme_ns_head_chr_uring_cmd, 442 }; 443 444 static int nvme_add_ns_head_cdev(struct nvme_ns_head *head) 445 { 446 int ret; 447 448 head->cdev_device.parent = &head->subsys->dev; 449 ret = dev_set_name(&head->cdev_device, "ng%dn%d", 450 head->subsys->instance, head->instance); 451 if (ret) 452 return ret; 453 ret = nvme_cdev_add(&head->cdev, &head->cdev_device, 454 &nvme_ns_head_chr_fops, THIS_MODULE); 455 return ret; 456 } 457 458 static void nvme_requeue_work(struct work_struct *work) 459 { 460 struct nvme_ns_head *head = 461 container_of(work, struct nvme_ns_head, requeue_work); 462 struct bio *bio, *next; 463 464 spin_lock_irq(&head->requeue_lock); 465 next = bio_list_get(&head->requeue_list); 466 spin_unlock_irq(&head->requeue_lock); 467 468 while ((bio = next) != NULL) { 469 next = bio->bi_next; 470 bio->bi_next = NULL; 471 472 submit_bio_noacct(bio); 473 } 474 } 475 476 int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) 477 { 478 bool vwc = false; 479 480 mutex_init(&head->lock); 481 bio_list_init(&head->requeue_list); 482 spin_lock_init(&head->requeue_lock); 483 INIT_WORK(&head->requeue_work, nvme_requeue_work); 484 485 /* 486 * Add a multipath node if the subsystems supports multiple controllers. 487 * We also do this for private namespaces as the namespace sharing flag 488 * could change after a rescan. 489 */ 490 if (!(ctrl->subsys->cmic & NVME_CTRL_CMIC_MULTI_CTRL) || 491 !nvme_is_unique_nsid(ctrl, head) || !multipath) 492 return 0; 493 494 head->disk = blk_alloc_disk(ctrl->numa_node); 495 if (!head->disk) 496 return -ENOMEM; 497 head->disk->fops = &nvme_ns_head_ops; 498 head->disk->private_data = head; 499 sprintf(head->disk->disk_name, "nvme%dn%d", 500 ctrl->subsys->instance, head->instance); 501 502 blk_queue_flag_set(QUEUE_FLAG_NONROT, head->disk->queue); 503 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, head->disk->queue); 504 /* 505 * This assumes all controllers that refer to a namespace either 506 * support poll queues or not. That is not a strict guarantee, 507 * but if the assumption is wrong the effect is only suboptimal 508 * performance but not correctness problem. 509 */ 510 if (ctrl->tagset->nr_maps > HCTX_TYPE_POLL && 511 ctrl->tagset->map[HCTX_TYPE_POLL].nr_queues) 512 blk_queue_flag_set(QUEUE_FLAG_POLL, head->disk->queue); 513 514 /* set to a default value of 512 until the disk is validated */ 515 blk_queue_logical_block_size(head->disk->queue, 512); 516 blk_set_stacking_limits(&head->disk->queue->limits); 517 518 /* we need to propagate up the VMC settings */ 519 if (ctrl->vwc & NVME_CTRL_VWC_PRESENT) 520 vwc = true; 521 blk_queue_write_cache(head->disk->queue, vwc, vwc); 522 return 0; 523 } 524 525 static void nvme_mpath_set_live(struct nvme_ns *ns) 526 { 527 struct nvme_ns_head *head = ns->head; 528 int rc; 529 530 if (!head->disk) 531 return; 532 533 /* 534 * test_and_set_bit() is used because it is protecting against two nvme 535 * paths simultaneously calling device_add_disk() on the same namespace 536 * head. 537 */ 538 if (!test_and_set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { 539 rc = device_add_disk(&head->subsys->dev, head->disk, 540 nvme_ns_id_attr_groups); 541 if (rc) { 542 clear_bit(NVME_NSHEAD_DISK_LIVE, &ns->flags); 543 return; 544 } 545 nvme_add_ns_head_cdev(head); 546 } 547 548 mutex_lock(&head->lock); 549 if (nvme_path_is_optimized(ns)) { 550 int node, srcu_idx; 551 552 srcu_idx = srcu_read_lock(&head->srcu); 553 for_each_node(node) 554 __nvme_find_path(head, node); 555 srcu_read_unlock(&head->srcu, srcu_idx); 556 } 557 mutex_unlock(&head->lock); 558 559 synchronize_srcu(&head->srcu); 560 kblockd_schedule_work(&head->requeue_work); 561 } 562 563 static int nvme_parse_ana_log(struct nvme_ctrl *ctrl, void *data, 564 int (*cb)(struct nvme_ctrl *ctrl, struct nvme_ana_group_desc *, 565 void *)) 566 { 567 void *base = ctrl->ana_log_buf; 568 size_t offset = sizeof(struct nvme_ana_rsp_hdr); 569 int error, i; 570 571 lockdep_assert_held(&ctrl->ana_lock); 572 573 for (i = 0; i < le16_to_cpu(ctrl->ana_log_buf->ngrps); i++) { 574 struct nvme_ana_group_desc *desc = base + offset; 575 u32 nr_nsids; 576 size_t nsid_buf_size; 577 578 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - sizeof(*desc))) 579 return -EINVAL; 580 581 nr_nsids = le32_to_cpu(desc->nnsids); 582 nsid_buf_size = flex_array_size(desc, nsids, nr_nsids); 583 584 if (WARN_ON_ONCE(desc->grpid == 0)) 585 return -EINVAL; 586 if (WARN_ON_ONCE(le32_to_cpu(desc->grpid) > ctrl->anagrpmax)) 587 return -EINVAL; 588 if (WARN_ON_ONCE(desc->state == 0)) 589 return -EINVAL; 590 if (WARN_ON_ONCE(desc->state > NVME_ANA_CHANGE)) 591 return -EINVAL; 592 593 offset += sizeof(*desc); 594 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - nsid_buf_size)) 595 return -EINVAL; 596 597 error = cb(ctrl, desc, data); 598 if (error) 599 return error; 600 601 offset += nsid_buf_size; 602 } 603 604 return 0; 605 } 606 607 static inline bool nvme_state_is_live(enum nvme_ana_state state) 608 { 609 return state == NVME_ANA_OPTIMIZED || state == NVME_ANA_NONOPTIMIZED; 610 } 611 612 static void nvme_update_ns_ana_state(struct nvme_ana_group_desc *desc, 613 struct nvme_ns *ns) 614 { 615 ns->ana_grpid = le32_to_cpu(desc->grpid); 616 ns->ana_state = desc->state; 617 clear_bit(NVME_NS_ANA_PENDING, &ns->flags); 618 /* 619 * nvme_mpath_set_live() will trigger I/O to the multipath path device 620 * and in turn to this path device. However we cannot accept this I/O 621 * if the controller is not live. This may deadlock if called from 622 * nvme_mpath_init_identify() and the ctrl will never complete 623 * initialization, preventing I/O from completing. For this case we 624 * will reprocess the ANA log page in nvme_mpath_update() once the 625 * controller is ready. 626 */ 627 if (nvme_state_is_live(ns->ana_state) && 628 ns->ctrl->state == NVME_CTRL_LIVE) 629 nvme_mpath_set_live(ns); 630 } 631 632 static int nvme_update_ana_state(struct nvme_ctrl *ctrl, 633 struct nvme_ana_group_desc *desc, void *data) 634 { 635 u32 nr_nsids = le32_to_cpu(desc->nnsids), n = 0; 636 unsigned *nr_change_groups = data; 637 struct nvme_ns *ns; 638 639 dev_dbg(ctrl->device, "ANA group %d: %s.\n", 640 le32_to_cpu(desc->grpid), 641 nvme_ana_state_names[desc->state]); 642 643 if (desc->state == NVME_ANA_CHANGE) 644 (*nr_change_groups)++; 645 646 if (!nr_nsids) 647 return 0; 648 649 down_read(&ctrl->namespaces_rwsem); 650 list_for_each_entry(ns, &ctrl->namespaces, list) { 651 unsigned nsid; 652 again: 653 nsid = le32_to_cpu(desc->nsids[n]); 654 if (ns->head->ns_id < nsid) 655 continue; 656 if (ns->head->ns_id == nsid) 657 nvme_update_ns_ana_state(desc, ns); 658 if (++n == nr_nsids) 659 break; 660 if (ns->head->ns_id > nsid) 661 goto again; 662 } 663 up_read(&ctrl->namespaces_rwsem); 664 return 0; 665 } 666 667 static int nvme_read_ana_log(struct nvme_ctrl *ctrl) 668 { 669 u32 nr_change_groups = 0; 670 int error; 671 672 mutex_lock(&ctrl->ana_lock); 673 error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_ANA, 0, NVME_CSI_NVM, 674 ctrl->ana_log_buf, ctrl->ana_log_size, 0); 675 if (error) { 676 dev_warn(ctrl->device, "Failed to get ANA log: %d\n", error); 677 goto out_unlock; 678 } 679 680 error = nvme_parse_ana_log(ctrl, &nr_change_groups, 681 nvme_update_ana_state); 682 if (error) 683 goto out_unlock; 684 685 /* 686 * In theory we should have an ANATT timer per group as they might enter 687 * the change state at different times. But that is a lot of overhead 688 * just to protect against a target that keeps entering new changes 689 * states while never finishing previous ones. But we'll still 690 * eventually time out once all groups are in change state, so this 691 * isn't a big deal. 692 * 693 * We also double the ANATT value to provide some slack for transports 694 * or AEN processing overhead. 695 */ 696 if (nr_change_groups) 697 mod_timer(&ctrl->anatt_timer, ctrl->anatt * HZ * 2 + jiffies); 698 else 699 del_timer_sync(&ctrl->anatt_timer); 700 out_unlock: 701 mutex_unlock(&ctrl->ana_lock); 702 return error; 703 } 704 705 static void nvme_ana_work(struct work_struct *work) 706 { 707 struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ana_work); 708 709 if (ctrl->state != NVME_CTRL_LIVE) 710 return; 711 712 nvme_read_ana_log(ctrl); 713 } 714 715 void nvme_mpath_update(struct nvme_ctrl *ctrl) 716 { 717 u32 nr_change_groups = 0; 718 719 if (!ctrl->ana_log_buf) 720 return; 721 722 mutex_lock(&ctrl->ana_lock); 723 nvme_parse_ana_log(ctrl, &nr_change_groups, nvme_update_ana_state); 724 mutex_unlock(&ctrl->ana_lock); 725 } 726 727 static void nvme_anatt_timeout(struct timer_list *t) 728 { 729 struct nvme_ctrl *ctrl = from_timer(ctrl, t, anatt_timer); 730 731 dev_info(ctrl->device, "ANATT timeout, resetting controller.\n"); 732 nvme_reset_ctrl(ctrl); 733 } 734 735 void nvme_mpath_stop(struct nvme_ctrl *ctrl) 736 { 737 if (!nvme_ctrl_use_ana(ctrl)) 738 return; 739 del_timer_sync(&ctrl->anatt_timer); 740 cancel_work_sync(&ctrl->ana_work); 741 } 742 743 #define SUBSYS_ATTR_RW(_name, _mode, _show, _store) \ 744 struct device_attribute subsys_attr_##_name = \ 745 __ATTR(_name, _mode, _show, _store) 746 747 static ssize_t nvme_subsys_iopolicy_show(struct device *dev, 748 struct device_attribute *attr, char *buf) 749 { 750 struct nvme_subsystem *subsys = 751 container_of(dev, struct nvme_subsystem, dev); 752 753 return sysfs_emit(buf, "%s\n", 754 nvme_iopolicy_names[READ_ONCE(subsys->iopolicy)]); 755 } 756 757 static ssize_t nvme_subsys_iopolicy_store(struct device *dev, 758 struct device_attribute *attr, const char *buf, size_t count) 759 { 760 struct nvme_subsystem *subsys = 761 container_of(dev, struct nvme_subsystem, dev); 762 int i; 763 764 for (i = 0; i < ARRAY_SIZE(nvme_iopolicy_names); i++) { 765 if (sysfs_streq(buf, nvme_iopolicy_names[i])) { 766 WRITE_ONCE(subsys->iopolicy, i); 767 return count; 768 } 769 } 770 771 return -EINVAL; 772 } 773 SUBSYS_ATTR_RW(iopolicy, S_IRUGO | S_IWUSR, 774 nvme_subsys_iopolicy_show, nvme_subsys_iopolicy_store); 775 776 static ssize_t ana_grpid_show(struct device *dev, struct device_attribute *attr, 777 char *buf) 778 { 779 return sysfs_emit(buf, "%d\n", nvme_get_ns_from_dev(dev)->ana_grpid); 780 } 781 DEVICE_ATTR_RO(ana_grpid); 782 783 static ssize_t ana_state_show(struct device *dev, struct device_attribute *attr, 784 char *buf) 785 { 786 struct nvme_ns *ns = nvme_get_ns_from_dev(dev); 787 788 return sysfs_emit(buf, "%s\n", nvme_ana_state_names[ns->ana_state]); 789 } 790 DEVICE_ATTR_RO(ana_state); 791 792 static int nvme_lookup_ana_group_desc(struct nvme_ctrl *ctrl, 793 struct nvme_ana_group_desc *desc, void *data) 794 { 795 struct nvme_ana_group_desc *dst = data; 796 797 if (desc->grpid != dst->grpid) 798 return 0; 799 800 *dst = *desc; 801 return -ENXIO; /* just break out of the loop */ 802 } 803 804 void nvme_mpath_add_disk(struct nvme_ns *ns, __le32 anagrpid) 805 { 806 if (nvme_ctrl_use_ana(ns->ctrl)) { 807 struct nvme_ana_group_desc desc = { 808 .grpid = anagrpid, 809 .state = 0, 810 }; 811 812 mutex_lock(&ns->ctrl->ana_lock); 813 ns->ana_grpid = le32_to_cpu(anagrpid); 814 nvme_parse_ana_log(ns->ctrl, &desc, nvme_lookup_ana_group_desc); 815 mutex_unlock(&ns->ctrl->ana_lock); 816 if (desc.state) { 817 /* found the group desc: update */ 818 nvme_update_ns_ana_state(&desc, ns); 819 } else { 820 /* group desc not found: trigger a re-read */ 821 set_bit(NVME_NS_ANA_PENDING, &ns->flags); 822 queue_work(nvme_wq, &ns->ctrl->ana_work); 823 } 824 } else { 825 ns->ana_state = NVME_ANA_OPTIMIZED; 826 nvme_mpath_set_live(ns); 827 } 828 829 if (blk_queue_stable_writes(ns->queue) && ns->head->disk) 830 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, 831 ns->head->disk->queue); 832 #ifdef CONFIG_BLK_DEV_ZONED 833 if (blk_queue_is_zoned(ns->queue) && ns->head->disk) 834 ns->head->disk->nr_zones = ns->disk->nr_zones; 835 #endif 836 } 837 838 void nvme_mpath_shutdown_disk(struct nvme_ns_head *head) 839 { 840 if (!head->disk) 841 return; 842 kblockd_schedule_work(&head->requeue_work); 843 if (test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { 844 nvme_cdev_del(&head->cdev, &head->cdev_device); 845 del_gendisk(head->disk); 846 } 847 } 848 849 void nvme_mpath_remove_disk(struct nvme_ns_head *head) 850 { 851 if (!head->disk) 852 return; 853 blk_mark_disk_dead(head->disk); 854 /* make sure all pending bios are cleaned up */ 855 kblockd_schedule_work(&head->requeue_work); 856 flush_work(&head->requeue_work); 857 put_disk(head->disk); 858 } 859 860 void nvme_mpath_init_ctrl(struct nvme_ctrl *ctrl) 861 { 862 mutex_init(&ctrl->ana_lock); 863 timer_setup(&ctrl->anatt_timer, nvme_anatt_timeout, 0); 864 INIT_WORK(&ctrl->ana_work, nvme_ana_work); 865 } 866 867 int nvme_mpath_init_identify(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) 868 { 869 size_t max_transfer_size = ctrl->max_hw_sectors << SECTOR_SHIFT; 870 size_t ana_log_size; 871 int error = 0; 872 873 /* check if multipath is enabled and we have the capability */ 874 if (!multipath || !ctrl->subsys || 875 !(ctrl->subsys->cmic & NVME_CTRL_CMIC_ANA)) 876 return 0; 877 878 if (!ctrl->max_namespaces || 879 ctrl->max_namespaces > le32_to_cpu(id->nn)) { 880 dev_err(ctrl->device, 881 "Invalid MNAN value %u\n", ctrl->max_namespaces); 882 return -EINVAL; 883 } 884 885 ctrl->anacap = id->anacap; 886 ctrl->anatt = id->anatt; 887 ctrl->nanagrpid = le32_to_cpu(id->nanagrpid); 888 ctrl->anagrpmax = le32_to_cpu(id->anagrpmax); 889 890 ana_log_size = sizeof(struct nvme_ana_rsp_hdr) + 891 ctrl->nanagrpid * sizeof(struct nvme_ana_group_desc) + 892 ctrl->max_namespaces * sizeof(__le32); 893 if (ana_log_size > max_transfer_size) { 894 dev_err(ctrl->device, 895 "ANA log page size (%zd) larger than MDTS (%zd).\n", 896 ana_log_size, max_transfer_size); 897 dev_err(ctrl->device, "disabling ANA support.\n"); 898 goto out_uninit; 899 } 900 if (ana_log_size > ctrl->ana_log_size) { 901 nvme_mpath_stop(ctrl); 902 nvme_mpath_uninit(ctrl); 903 ctrl->ana_log_buf = kvmalloc(ana_log_size, GFP_KERNEL); 904 if (!ctrl->ana_log_buf) 905 return -ENOMEM; 906 } 907 ctrl->ana_log_size = ana_log_size; 908 error = nvme_read_ana_log(ctrl); 909 if (error) 910 goto out_uninit; 911 return 0; 912 913 out_uninit: 914 nvme_mpath_uninit(ctrl); 915 return error; 916 } 917 918 void nvme_mpath_uninit(struct nvme_ctrl *ctrl) 919 { 920 kvfree(ctrl->ana_log_buf); 921 ctrl->ana_log_buf = NULL; 922 ctrl->ana_log_size = 0; 923 } 924