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_mpath_start_request(struct request *rq) 118 { 119 struct nvme_ns *ns = rq->q->queuedata; 120 struct gendisk *disk = ns->head->disk; 121 122 if (!blk_queue_io_stat(disk->queue) || blk_rq_is_passthrough(rq)) 123 return; 124 125 nvme_req(rq)->flags |= NVME_MPATH_IO_STATS; 126 nvme_req(rq)->start_time = bdev_start_io_acct(disk->part0, req_op(rq), 127 jiffies); 128 } 129 EXPORT_SYMBOL_GPL(nvme_mpath_start_request); 130 131 void nvme_mpath_end_request(struct request *rq) 132 { 133 struct nvme_ns *ns = rq->q->queuedata; 134 135 if (!(nvme_req(rq)->flags & NVME_MPATH_IO_STATS)) 136 return; 137 bdev_end_io_acct(ns->head->disk->part0, req_op(rq), 138 blk_rq_bytes(rq) >> SECTOR_SHIFT, 139 nvme_req(rq)->start_time); 140 } 141 142 void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl) 143 { 144 struct nvme_ns *ns; 145 146 down_read(&ctrl->namespaces_rwsem); 147 list_for_each_entry(ns, &ctrl->namespaces, list) { 148 if (!ns->head->disk) 149 continue; 150 kblockd_schedule_work(&ns->head->requeue_work); 151 if (ctrl->state == NVME_CTRL_LIVE) 152 disk_uevent(ns->head->disk, KOBJ_CHANGE); 153 } 154 up_read(&ctrl->namespaces_rwsem); 155 } 156 157 static const char *nvme_ana_state_names[] = { 158 [0] = "invalid state", 159 [NVME_ANA_OPTIMIZED] = "optimized", 160 [NVME_ANA_NONOPTIMIZED] = "non-optimized", 161 [NVME_ANA_INACCESSIBLE] = "inaccessible", 162 [NVME_ANA_PERSISTENT_LOSS] = "persistent-loss", 163 [NVME_ANA_CHANGE] = "change", 164 }; 165 166 bool nvme_mpath_clear_current_path(struct nvme_ns *ns) 167 { 168 struct nvme_ns_head *head = ns->head; 169 bool changed = false; 170 int node; 171 172 if (!head) 173 goto out; 174 175 for_each_node(node) { 176 if (ns == rcu_access_pointer(head->current_path[node])) { 177 rcu_assign_pointer(head->current_path[node], NULL); 178 changed = true; 179 } 180 } 181 out: 182 return changed; 183 } 184 185 void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl) 186 { 187 struct nvme_ns *ns; 188 189 down_read(&ctrl->namespaces_rwsem); 190 list_for_each_entry(ns, &ctrl->namespaces, list) { 191 nvme_mpath_clear_current_path(ns); 192 kblockd_schedule_work(&ns->head->requeue_work); 193 } 194 up_read(&ctrl->namespaces_rwsem); 195 } 196 197 void nvme_mpath_revalidate_paths(struct nvme_ns *ns) 198 { 199 struct nvme_ns_head *head = ns->head; 200 sector_t capacity = get_capacity(head->disk); 201 int node; 202 int srcu_idx; 203 204 srcu_idx = srcu_read_lock(&head->srcu); 205 list_for_each_entry_rcu(ns, &head->list, siblings) { 206 if (capacity != get_capacity(ns->disk)) 207 clear_bit(NVME_NS_READY, &ns->flags); 208 } 209 srcu_read_unlock(&head->srcu, srcu_idx); 210 211 for_each_node(node) 212 rcu_assign_pointer(head->current_path[node], NULL); 213 kblockd_schedule_work(&head->requeue_work); 214 } 215 216 static bool nvme_path_is_disabled(struct nvme_ns *ns) 217 { 218 /* 219 * We don't treat NVME_CTRL_DELETING as a disabled path as I/O should 220 * still be able to complete assuming that the controller is connected. 221 * Otherwise it will fail immediately and return to the requeue list. 222 */ 223 if (ns->ctrl->state != NVME_CTRL_LIVE && 224 ns->ctrl->state != NVME_CTRL_DELETING) 225 return true; 226 if (test_bit(NVME_NS_ANA_PENDING, &ns->flags) || 227 !test_bit(NVME_NS_READY, &ns->flags)) 228 return true; 229 return false; 230 } 231 232 static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head, int node) 233 { 234 int found_distance = INT_MAX, fallback_distance = INT_MAX, distance; 235 struct nvme_ns *found = NULL, *fallback = NULL, *ns; 236 237 list_for_each_entry_rcu(ns, &head->list, siblings) { 238 if (nvme_path_is_disabled(ns)) 239 continue; 240 241 if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_NUMA) 242 distance = node_distance(node, ns->ctrl->numa_node); 243 else 244 distance = LOCAL_DISTANCE; 245 246 switch (ns->ana_state) { 247 case NVME_ANA_OPTIMIZED: 248 if (distance < found_distance) { 249 found_distance = distance; 250 found = ns; 251 } 252 break; 253 case NVME_ANA_NONOPTIMIZED: 254 if (distance < fallback_distance) { 255 fallback_distance = distance; 256 fallback = ns; 257 } 258 break; 259 default: 260 break; 261 } 262 } 263 264 if (!found) 265 found = fallback; 266 if (found) 267 rcu_assign_pointer(head->current_path[node], found); 268 return found; 269 } 270 271 static struct nvme_ns *nvme_next_ns(struct nvme_ns_head *head, 272 struct nvme_ns *ns) 273 { 274 ns = list_next_or_null_rcu(&head->list, &ns->siblings, struct nvme_ns, 275 siblings); 276 if (ns) 277 return ns; 278 return list_first_or_null_rcu(&head->list, struct nvme_ns, siblings); 279 } 280 281 static struct nvme_ns *nvme_round_robin_path(struct nvme_ns_head *head, 282 int node, struct nvme_ns *old) 283 { 284 struct nvme_ns *ns, *found = NULL; 285 286 if (list_is_singular(&head->list)) { 287 if (nvme_path_is_disabled(old)) 288 return NULL; 289 return old; 290 } 291 292 for (ns = nvme_next_ns(head, old); 293 ns && ns != old; 294 ns = nvme_next_ns(head, ns)) { 295 if (nvme_path_is_disabled(ns)) 296 continue; 297 298 if (ns->ana_state == NVME_ANA_OPTIMIZED) { 299 found = ns; 300 goto out; 301 } 302 if (ns->ana_state == NVME_ANA_NONOPTIMIZED) 303 found = ns; 304 } 305 306 /* 307 * The loop above skips the current path for round-robin semantics. 308 * Fall back to the current path if either: 309 * - no other optimized path found and current is optimized, 310 * - no other usable path found and current is usable. 311 */ 312 if (!nvme_path_is_disabled(old) && 313 (old->ana_state == NVME_ANA_OPTIMIZED || 314 (!found && old->ana_state == NVME_ANA_NONOPTIMIZED))) 315 return old; 316 317 if (!found) 318 return NULL; 319 out: 320 rcu_assign_pointer(head->current_path[node], found); 321 return found; 322 } 323 324 static inline bool nvme_path_is_optimized(struct nvme_ns *ns) 325 { 326 return ns->ctrl->state == NVME_CTRL_LIVE && 327 ns->ana_state == NVME_ANA_OPTIMIZED; 328 } 329 330 inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head) 331 { 332 int node = numa_node_id(); 333 struct nvme_ns *ns; 334 335 ns = srcu_dereference(head->current_path[node], &head->srcu); 336 if (unlikely(!ns)) 337 return __nvme_find_path(head, node); 338 339 if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_RR) 340 return nvme_round_robin_path(head, node, ns); 341 if (unlikely(!nvme_path_is_optimized(ns))) 342 return __nvme_find_path(head, node); 343 return ns; 344 } 345 346 static bool nvme_available_path(struct nvme_ns_head *head) 347 { 348 struct nvme_ns *ns; 349 350 list_for_each_entry_rcu(ns, &head->list, siblings) { 351 if (test_bit(NVME_CTRL_FAILFAST_EXPIRED, &ns->ctrl->flags)) 352 continue; 353 switch (ns->ctrl->state) { 354 case NVME_CTRL_LIVE: 355 case NVME_CTRL_RESETTING: 356 case NVME_CTRL_CONNECTING: 357 /* fallthru */ 358 return true; 359 default: 360 break; 361 } 362 } 363 return false; 364 } 365 366 static void nvme_ns_head_submit_bio(struct bio *bio) 367 { 368 struct nvme_ns_head *head = bio->bi_bdev->bd_disk->private_data; 369 struct device *dev = disk_to_dev(head->disk); 370 struct nvme_ns *ns; 371 int srcu_idx; 372 373 /* 374 * The namespace might be going away and the bio might be moved to a 375 * different queue via blk_steal_bios(), so we need to use the bio_split 376 * pool from the original queue to allocate the bvecs from. 377 */ 378 bio = bio_split_to_limits(bio); 379 if (!bio) 380 return; 381 382 srcu_idx = srcu_read_lock(&head->srcu); 383 ns = nvme_find_path(head); 384 if (likely(ns)) { 385 bio_set_dev(bio, ns->disk->part0); 386 bio->bi_opf |= REQ_NVME_MPATH; 387 trace_block_bio_remap(bio, disk_devt(ns->head->disk), 388 bio->bi_iter.bi_sector); 389 submit_bio_noacct(bio); 390 } else if (nvme_available_path(head)) { 391 dev_warn_ratelimited(dev, "no usable path - requeuing I/O\n"); 392 393 spin_lock_irq(&head->requeue_lock); 394 bio_list_add(&head->requeue_list, bio); 395 spin_unlock_irq(&head->requeue_lock); 396 } else { 397 dev_warn_ratelimited(dev, "no available path - failing I/O\n"); 398 399 bio_io_error(bio); 400 } 401 402 srcu_read_unlock(&head->srcu, srcu_idx); 403 } 404 405 static int nvme_ns_head_open(struct block_device *bdev, fmode_t mode) 406 { 407 if (!nvme_tryget_ns_head(bdev->bd_disk->private_data)) 408 return -ENXIO; 409 return 0; 410 } 411 412 static void nvme_ns_head_release(struct gendisk *disk, fmode_t mode) 413 { 414 nvme_put_ns_head(disk->private_data); 415 } 416 417 #ifdef CONFIG_BLK_DEV_ZONED 418 static int nvme_ns_head_report_zones(struct gendisk *disk, sector_t sector, 419 unsigned int nr_zones, report_zones_cb cb, void *data) 420 { 421 struct nvme_ns_head *head = disk->private_data; 422 struct nvme_ns *ns; 423 int srcu_idx, ret = -EWOULDBLOCK; 424 425 srcu_idx = srcu_read_lock(&head->srcu); 426 ns = nvme_find_path(head); 427 if (ns) 428 ret = nvme_ns_report_zones(ns, sector, nr_zones, cb, data); 429 srcu_read_unlock(&head->srcu, srcu_idx); 430 return ret; 431 } 432 #else 433 #define nvme_ns_head_report_zones NULL 434 #endif /* CONFIG_BLK_DEV_ZONED */ 435 436 const struct block_device_operations nvme_ns_head_ops = { 437 .owner = THIS_MODULE, 438 .submit_bio = nvme_ns_head_submit_bio, 439 .open = nvme_ns_head_open, 440 .release = nvme_ns_head_release, 441 .ioctl = nvme_ns_head_ioctl, 442 .compat_ioctl = blkdev_compat_ptr_ioctl, 443 .getgeo = nvme_getgeo, 444 .report_zones = nvme_ns_head_report_zones, 445 .pr_ops = &nvme_pr_ops, 446 }; 447 448 static inline struct nvme_ns_head *cdev_to_ns_head(struct cdev *cdev) 449 { 450 return container_of(cdev, struct nvme_ns_head, cdev); 451 } 452 453 static int nvme_ns_head_chr_open(struct inode *inode, struct file *file) 454 { 455 if (!nvme_tryget_ns_head(cdev_to_ns_head(inode->i_cdev))) 456 return -ENXIO; 457 return 0; 458 } 459 460 static int nvme_ns_head_chr_release(struct inode *inode, struct file *file) 461 { 462 nvme_put_ns_head(cdev_to_ns_head(inode->i_cdev)); 463 return 0; 464 } 465 466 static const struct file_operations nvme_ns_head_chr_fops = { 467 .owner = THIS_MODULE, 468 .open = nvme_ns_head_chr_open, 469 .release = nvme_ns_head_chr_release, 470 .unlocked_ioctl = nvme_ns_head_chr_ioctl, 471 .compat_ioctl = compat_ptr_ioctl, 472 .uring_cmd = nvme_ns_head_chr_uring_cmd, 473 .uring_cmd_iopoll = nvme_ns_head_chr_uring_cmd_iopoll, 474 }; 475 476 static int nvme_add_ns_head_cdev(struct nvme_ns_head *head) 477 { 478 int ret; 479 480 head->cdev_device.parent = &head->subsys->dev; 481 ret = dev_set_name(&head->cdev_device, "ng%dn%d", 482 head->subsys->instance, head->instance); 483 if (ret) 484 return ret; 485 ret = nvme_cdev_add(&head->cdev, &head->cdev_device, 486 &nvme_ns_head_chr_fops, THIS_MODULE); 487 return ret; 488 } 489 490 static void nvme_requeue_work(struct work_struct *work) 491 { 492 struct nvme_ns_head *head = 493 container_of(work, struct nvme_ns_head, requeue_work); 494 struct bio *bio, *next; 495 496 spin_lock_irq(&head->requeue_lock); 497 next = bio_list_get(&head->requeue_list); 498 spin_unlock_irq(&head->requeue_lock); 499 500 while ((bio = next) != NULL) { 501 next = bio->bi_next; 502 bio->bi_next = NULL; 503 504 submit_bio_noacct(bio); 505 } 506 } 507 508 int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) 509 { 510 bool vwc = false; 511 512 mutex_init(&head->lock); 513 bio_list_init(&head->requeue_list); 514 spin_lock_init(&head->requeue_lock); 515 INIT_WORK(&head->requeue_work, nvme_requeue_work); 516 517 /* 518 * Add a multipath node if the subsystems supports multiple controllers. 519 * We also do this for private namespaces as the namespace sharing flag 520 * could change after a rescan. 521 */ 522 if (!(ctrl->subsys->cmic & NVME_CTRL_CMIC_MULTI_CTRL) || 523 !nvme_is_unique_nsid(ctrl, head) || !multipath) 524 return 0; 525 526 head->disk = blk_alloc_disk(ctrl->numa_node); 527 if (!head->disk) 528 return -ENOMEM; 529 head->disk->fops = &nvme_ns_head_ops; 530 head->disk->private_data = head; 531 sprintf(head->disk->disk_name, "nvme%dn%d", 532 ctrl->subsys->instance, head->instance); 533 534 blk_queue_flag_set(QUEUE_FLAG_NONROT, head->disk->queue); 535 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, head->disk->queue); 536 blk_queue_flag_set(QUEUE_FLAG_IO_STAT, head->disk->queue); 537 /* 538 * This assumes all controllers that refer to a namespace either 539 * support poll queues or not. That is not a strict guarantee, 540 * but if the assumption is wrong the effect is only suboptimal 541 * performance but not correctness problem. 542 */ 543 if (ctrl->tagset->nr_maps > HCTX_TYPE_POLL && 544 ctrl->tagset->map[HCTX_TYPE_POLL].nr_queues) 545 blk_queue_flag_set(QUEUE_FLAG_POLL, head->disk->queue); 546 547 /* set to a default value of 512 until the disk is validated */ 548 blk_queue_logical_block_size(head->disk->queue, 512); 549 blk_set_stacking_limits(&head->disk->queue->limits); 550 blk_queue_dma_alignment(head->disk->queue, 3); 551 552 /* we need to propagate up the VMC settings */ 553 if (ctrl->vwc & NVME_CTRL_VWC_PRESENT) 554 vwc = true; 555 blk_queue_write_cache(head->disk->queue, vwc, vwc); 556 return 0; 557 } 558 559 static void nvme_mpath_set_live(struct nvme_ns *ns) 560 { 561 struct nvme_ns_head *head = ns->head; 562 int rc; 563 564 if (!head->disk) 565 return; 566 567 /* 568 * test_and_set_bit() is used because it is protecting against two nvme 569 * paths simultaneously calling device_add_disk() on the same namespace 570 * head. 571 */ 572 if (!test_and_set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { 573 rc = device_add_disk(&head->subsys->dev, head->disk, 574 nvme_ns_id_attr_groups); 575 if (rc) { 576 clear_bit(NVME_NSHEAD_DISK_LIVE, &ns->flags); 577 return; 578 } 579 nvme_add_ns_head_cdev(head); 580 } 581 582 mutex_lock(&head->lock); 583 if (nvme_path_is_optimized(ns)) { 584 int node, srcu_idx; 585 586 srcu_idx = srcu_read_lock(&head->srcu); 587 for_each_node(node) 588 __nvme_find_path(head, node); 589 srcu_read_unlock(&head->srcu, srcu_idx); 590 } 591 mutex_unlock(&head->lock); 592 593 synchronize_srcu(&head->srcu); 594 kblockd_schedule_work(&head->requeue_work); 595 } 596 597 static int nvme_parse_ana_log(struct nvme_ctrl *ctrl, void *data, 598 int (*cb)(struct nvme_ctrl *ctrl, struct nvme_ana_group_desc *, 599 void *)) 600 { 601 void *base = ctrl->ana_log_buf; 602 size_t offset = sizeof(struct nvme_ana_rsp_hdr); 603 int error, i; 604 605 lockdep_assert_held(&ctrl->ana_lock); 606 607 for (i = 0; i < le16_to_cpu(ctrl->ana_log_buf->ngrps); i++) { 608 struct nvme_ana_group_desc *desc = base + offset; 609 u32 nr_nsids; 610 size_t nsid_buf_size; 611 612 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - sizeof(*desc))) 613 return -EINVAL; 614 615 nr_nsids = le32_to_cpu(desc->nnsids); 616 nsid_buf_size = flex_array_size(desc, nsids, nr_nsids); 617 618 if (WARN_ON_ONCE(desc->grpid == 0)) 619 return -EINVAL; 620 if (WARN_ON_ONCE(le32_to_cpu(desc->grpid) > ctrl->anagrpmax)) 621 return -EINVAL; 622 if (WARN_ON_ONCE(desc->state == 0)) 623 return -EINVAL; 624 if (WARN_ON_ONCE(desc->state > NVME_ANA_CHANGE)) 625 return -EINVAL; 626 627 offset += sizeof(*desc); 628 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - nsid_buf_size)) 629 return -EINVAL; 630 631 error = cb(ctrl, desc, data); 632 if (error) 633 return error; 634 635 offset += nsid_buf_size; 636 } 637 638 return 0; 639 } 640 641 static inline bool nvme_state_is_live(enum nvme_ana_state state) 642 { 643 return state == NVME_ANA_OPTIMIZED || state == NVME_ANA_NONOPTIMIZED; 644 } 645 646 static void nvme_update_ns_ana_state(struct nvme_ana_group_desc *desc, 647 struct nvme_ns *ns) 648 { 649 ns->ana_grpid = le32_to_cpu(desc->grpid); 650 ns->ana_state = desc->state; 651 clear_bit(NVME_NS_ANA_PENDING, &ns->flags); 652 /* 653 * nvme_mpath_set_live() will trigger I/O to the multipath path device 654 * and in turn to this path device. However we cannot accept this I/O 655 * if the controller is not live. This may deadlock if called from 656 * nvme_mpath_init_identify() and the ctrl will never complete 657 * initialization, preventing I/O from completing. For this case we 658 * will reprocess the ANA log page in nvme_mpath_update() once the 659 * controller is ready. 660 */ 661 if (nvme_state_is_live(ns->ana_state) && 662 ns->ctrl->state == NVME_CTRL_LIVE) 663 nvme_mpath_set_live(ns); 664 } 665 666 static int nvme_update_ana_state(struct nvme_ctrl *ctrl, 667 struct nvme_ana_group_desc *desc, void *data) 668 { 669 u32 nr_nsids = le32_to_cpu(desc->nnsids), n = 0; 670 unsigned *nr_change_groups = data; 671 struct nvme_ns *ns; 672 673 dev_dbg(ctrl->device, "ANA group %d: %s.\n", 674 le32_to_cpu(desc->grpid), 675 nvme_ana_state_names[desc->state]); 676 677 if (desc->state == NVME_ANA_CHANGE) 678 (*nr_change_groups)++; 679 680 if (!nr_nsids) 681 return 0; 682 683 down_read(&ctrl->namespaces_rwsem); 684 list_for_each_entry(ns, &ctrl->namespaces, list) { 685 unsigned nsid; 686 again: 687 nsid = le32_to_cpu(desc->nsids[n]); 688 if (ns->head->ns_id < nsid) 689 continue; 690 if (ns->head->ns_id == nsid) 691 nvme_update_ns_ana_state(desc, ns); 692 if (++n == nr_nsids) 693 break; 694 if (ns->head->ns_id > nsid) 695 goto again; 696 } 697 up_read(&ctrl->namespaces_rwsem); 698 return 0; 699 } 700 701 static int nvme_read_ana_log(struct nvme_ctrl *ctrl) 702 { 703 u32 nr_change_groups = 0; 704 int error; 705 706 mutex_lock(&ctrl->ana_lock); 707 error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_ANA, 0, NVME_CSI_NVM, 708 ctrl->ana_log_buf, ctrl->ana_log_size, 0); 709 if (error) { 710 dev_warn(ctrl->device, "Failed to get ANA log: %d\n", error); 711 goto out_unlock; 712 } 713 714 error = nvme_parse_ana_log(ctrl, &nr_change_groups, 715 nvme_update_ana_state); 716 if (error) 717 goto out_unlock; 718 719 /* 720 * In theory we should have an ANATT timer per group as they might enter 721 * the change state at different times. But that is a lot of overhead 722 * just to protect against a target that keeps entering new changes 723 * states while never finishing previous ones. But we'll still 724 * eventually time out once all groups are in change state, so this 725 * isn't a big deal. 726 * 727 * We also double the ANATT value to provide some slack for transports 728 * or AEN processing overhead. 729 */ 730 if (nr_change_groups) 731 mod_timer(&ctrl->anatt_timer, ctrl->anatt * HZ * 2 + jiffies); 732 else 733 del_timer_sync(&ctrl->anatt_timer); 734 out_unlock: 735 mutex_unlock(&ctrl->ana_lock); 736 return error; 737 } 738 739 static void nvme_ana_work(struct work_struct *work) 740 { 741 struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ana_work); 742 743 if (ctrl->state != NVME_CTRL_LIVE) 744 return; 745 746 nvme_read_ana_log(ctrl); 747 } 748 749 void nvme_mpath_update(struct nvme_ctrl *ctrl) 750 { 751 u32 nr_change_groups = 0; 752 753 if (!ctrl->ana_log_buf) 754 return; 755 756 mutex_lock(&ctrl->ana_lock); 757 nvme_parse_ana_log(ctrl, &nr_change_groups, nvme_update_ana_state); 758 mutex_unlock(&ctrl->ana_lock); 759 } 760 761 static void nvme_anatt_timeout(struct timer_list *t) 762 { 763 struct nvme_ctrl *ctrl = from_timer(ctrl, t, anatt_timer); 764 765 dev_info(ctrl->device, "ANATT timeout, resetting controller.\n"); 766 nvme_reset_ctrl(ctrl); 767 } 768 769 void nvme_mpath_stop(struct nvme_ctrl *ctrl) 770 { 771 if (!nvme_ctrl_use_ana(ctrl)) 772 return; 773 del_timer_sync(&ctrl->anatt_timer); 774 cancel_work_sync(&ctrl->ana_work); 775 } 776 777 #define SUBSYS_ATTR_RW(_name, _mode, _show, _store) \ 778 struct device_attribute subsys_attr_##_name = \ 779 __ATTR(_name, _mode, _show, _store) 780 781 static ssize_t nvme_subsys_iopolicy_show(struct device *dev, 782 struct device_attribute *attr, char *buf) 783 { 784 struct nvme_subsystem *subsys = 785 container_of(dev, struct nvme_subsystem, dev); 786 787 return sysfs_emit(buf, "%s\n", 788 nvme_iopolicy_names[READ_ONCE(subsys->iopolicy)]); 789 } 790 791 static ssize_t nvme_subsys_iopolicy_store(struct device *dev, 792 struct device_attribute *attr, const char *buf, size_t count) 793 { 794 struct nvme_subsystem *subsys = 795 container_of(dev, struct nvme_subsystem, dev); 796 int i; 797 798 for (i = 0; i < ARRAY_SIZE(nvme_iopolicy_names); i++) { 799 if (sysfs_streq(buf, nvme_iopolicy_names[i])) { 800 WRITE_ONCE(subsys->iopolicy, i); 801 return count; 802 } 803 } 804 805 return -EINVAL; 806 } 807 SUBSYS_ATTR_RW(iopolicy, S_IRUGO | S_IWUSR, 808 nvme_subsys_iopolicy_show, nvme_subsys_iopolicy_store); 809 810 static ssize_t ana_grpid_show(struct device *dev, struct device_attribute *attr, 811 char *buf) 812 { 813 return sysfs_emit(buf, "%d\n", nvme_get_ns_from_dev(dev)->ana_grpid); 814 } 815 DEVICE_ATTR_RO(ana_grpid); 816 817 static ssize_t ana_state_show(struct device *dev, struct device_attribute *attr, 818 char *buf) 819 { 820 struct nvme_ns *ns = nvme_get_ns_from_dev(dev); 821 822 return sysfs_emit(buf, "%s\n", nvme_ana_state_names[ns->ana_state]); 823 } 824 DEVICE_ATTR_RO(ana_state); 825 826 static int nvme_lookup_ana_group_desc(struct nvme_ctrl *ctrl, 827 struct nvme_ana_group_desc *desc, void *data) 828 { 829 struct nvme_ana_group_desc *dst = data; 830 831 if (desc->grpid != dst->grpid) 832 return 0; 833 834 *dst = *desc; 835 return -ENXIO; /* just break out of the loop */ 836 } 837 838 void nvme_mpath_add_disk(struct nvme_ns *ns, __le32 anagrpid) 839 { 840 if (nvme_ctrl_use_ana(ns->ctrl)) { 841 struct nvme_ana_group_desc desc = { 842 .grpid = anagrpid, 843 .state = 0, 844 }; 845 846 mutex_lock(&ns->ctrl->ana_lock); 847 ns->ana_grpid = le32_to_cpu(anagrpid); 848 nvme_parse_ana_log(ns->ctrl, &desc, nvme_lookup_ana_group_desc); 849 mutex_unlock(&ns->ctrl->ana_lock); 850 if (desc.state) { 851 /* found the group desc: update */ 852 nvme_update_ns_ana_state(&desc, ns); 853 } else { 854 /* group desc not found: trigger a re-read */ 855 set_bit(NVME_NS_ANA_PENDING, &ns->flags); 856 queue_work(nvme_wq, &ns->ctrl->ana_work); 857 } 858 } else { 859 ns->ana_state = NVME_ANA_OPTIMIZED; 860 nvme_mpath_set_live(ns); 861 } 862 863 if (blk_queue_stable_writes(ns->queue) && ns->head->disk) 864 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, 865 ns->head->disk->queue); 866 #ifdef CONFIG_BLK_DEV_ZONED 867 if (blk_queue_is_zoned(ns->queue) && ns->head->disk) 868 ns->head->disk->nr_zones = ns->disk->nr_zones; 869 #endif 870 } 871 872 void nvme_mpath_shutdown_disk(struct nvme_ns_head *head) 873 { 874 if (!head->disk) 875 return; 876 kblockd_schedule_work(&head->requeue_work); 877 if (test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { 878 nvme_cdev_del(&head->cdev, &head->cdev_device); 879 del_gendisk(head->disk); 880 } 881 } 882 883 void nvme_mpath_remove_disk(struct nvme_ns_head *head) 884 { 885 if (!head->disk) 886 return; 887 /* make sure all pending bios are cleaned up */ 888 kblockd_schedule_work(&head->requeue_work); 889 flush_work(&head->requeue_work); 890 put_disk(head->disk); 891 } 892 893 void nvme_mpath_init_ctrl(struct nvme_ctrl *ctrl) 894 { 895 mutex_init(&ctrl->ana_lock); 896 timer_setup(&ctrl->anatt_timer, nvme_anatt_timeout, 0); 897 INIT_WORK(&ctrl->ana_work, nvme_ana_work); 898 } 899 900 int nvme_mpath_init_identify(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) 901 { 902 size_t max_transfer_size = ctrl->max_hw_sectors << SECTOR_SHIFT; 903 size_t ana_log_size; 904 int error = 0; 905 906 /* check if multipath is enabled and we have the capability */ 907 if (!multipath || !ctrl->subsys || 908 !(ctrl->subsys->cmic & NVME_CTRL_CMIC_ANA)) 909 return 0; 910 911 if (!ctrl->max_namespaces || 912 ctrl->max_namespaces > le32_to_cpu(id->nn)) { 913 dev_err(ctrl->device, 914 "Invalid MNAN value %u\n", ctrl->max_namespaces); 915 return -EINVAL; 916 } 917 918 ctrl->anacap = id->anacap; 919 ctrl->anatt = id->anatt; 920 ctrl->nanagrpid = le32_to_cpu(id->nanagrpid); 921 ctrl->anagrpmax = le32_to_cpu(id->anagrpmax); 922 923 ana_log_size = sizeof(struct nvme_ana_rsp_hdr) + 924 ctrl->nanagrpid * sizeof(struct nvme_ana_group_desc) + 925 ctrl->max_namespaces * sizeof(__le32); 926 if (ana_log_size > max_transfer_size) { 927 dev_err(ctrl->device, 928 "ANA log page size (%zd) larger than MDTS (%zd).\n", 929 ana_log_size, max_transfer_size); 930 dev_err(ctrl->device, "disabling ANA support.\n"); 931 goto out_uninit; 932 } 933 if (ana_log_size > ctrl->ana_log_size) { 934 nvme_mpath_stop(ctrl); 935 nvme_mpath_uninit(ctrl); 936 ctrl->ana_log_buf = kvmalloc(ana_log_size, GFP_KERNEL); 937 if (!ctrl->ana_log_buf) 938 return -ENOMEM; 939 } 940 ctrl->ana_log_size = ana_log_size; 941 error = nvme_read_ana_log(ctrl); 942 if (error) 943 goto out_uninit; 944 return 0; 945 946 out_uninit: 947 nvme_mpath_uninit(ctrl); 948 return error; 949 } 950 951 void nvme_mpath_uninit(struct nvme_ctrl *ctrl) 952 { 953 kvfree(ctrl->ana_log_buf); 954 ctrl->ana_log_buf = NULL; 955 ctrl->ana_log_size = 0; 956 } 957