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md.h
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linux-6.19.14/drivers/md/md.h
1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* 3 md.h : kernel internal structure of the Linux MD driver 4 Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman 5 6*/ 7 8#ifndef _MD_MD_H 9#define _MD_MD_H 10 11#include <linux/blkdev.h> 12#include <linux/backing-dev.h> 13#include <linux/badblocks.h> 14#include <linux/kobject.h> 15#include <linux/list.h> 16#include <linux/mm.h> 17#include <linux/mutex.h> 18#include <linux/timer.h> 19#include <linux/wait.h> 20#include <linux/workqueue.h> 21#include <linux/raid/md_u.h> 22#include <trace/events/block.h> 23 24#define MaxSector (~(sector_t)0) 25 26enum md_submodule_type { 27 MD_PERSONALITY = 0, 28 MD_CLUSTER, 29 MD_BITMAP, 30}; 31 32enum md_submodule_id { 33 ID_LINEAR = LEVEL_LINEAR, 34 ID_RAID0 = 0, 35 ID_RAID1 = 1, 36 ID_RAID4 = 4, 37 ID_RAID5 = 5, 38 ID_RAID6 = 6, 39 ID_RAID10 = 10, 40 ID_CLUSTER, 41 ID_BITMAP, 42 ID_LLBITMAP, 43 ID_BITMAP_NONE, 44}; 45 46struct md_submodule_head { 47 enum md_submodule_type type; 48 enum md_submodule_id id; 49 const char *name; 50 struct module *owner; 51}; 52 53/* 54 * These flags should really be called "NO_RETRY" rather than 55 * "FAILFAST" because they don't make any promise about time lapse, 56 * only about the number of retries, which will be zero. 57 * REQ_FAILFAST_DRIVER is not included because 58 * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.") 59 * seems to suggest that the errors it avoids retrying should usually 60 * be retried. 61 */ 62#define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT) 63 64/* Status of sync thread. */ 65enum sync_action { 66 /* 67 * Represent by MD_RECOVERY_SYNC, start when: 68 * 1) after assemble, sync data from first rdev to other copies, this 69 * must be done first before other sync actions and will only execute 70 * once; 71 * 2) resize the array(notice that this is not reshape), sync data for 72 * the new range; 73 */ 74 ACTION_RESYNC, 75 /* 76 * Represent by MD_RECOVERY_RECOVER, start when: 77 * 1) for new replacement, sync data based on the replace rdev or 78 * available copies from other rdev; 79 * 2) for new member disk while the array is degraded, sync data from 80 * other rdev; 81 * 3) reassemble after power failure or re-add a hot removed rdev, sync 82 * data from first rdev to other copies based on bitmap; 83 */ 84 ACTION_RECOVER, 85 /* 86 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED | 87 * MD_RECOVERY_CHECK, start when user echo "check" to sysfs api 88 * sync_action, used to check if data copies from differenct rdev are 89 * the same. The number of mismatch sectors will be exported to user 90 * by sysfs api mismatch_cnt; 91 */ 92 ACTION_CHECK, 93 /* 94 * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED, start when 95 * user echo "repair" to sysfs api sync_action, usually paired with 96 * ACTION_CHECK, used to force syncing data once user found that there 97 * are inconsistent data, 98 */ 99 ACTION_REPAIR, 100 /* 101 * Represent by MD_RECOVERY_RESHAPE, start when new member disk is added 102 * to the conf, notice that this is different from spares or 103 * replacement; 104 */ 105 ACTION_RESHAPE, 106 /* 107 * Represent by MD_RECOVERY_FROZEN, can be set by sysfs api sync_action 108 * or internal usage like setting the array read-only, will forbid above 109 * actions. 110 */ 111 ACTION_FROZEN, 112 /* 113 * All above actions don't match. 114 */ 115 ACTION_IDLE, 116 NR_SYNC_ACTIONS, 117}; 118 119/* 120 * The struct embedded in rdev is used to serialize IO. 121 */ 122struct serial_in_rdev { 123 struct rb_root_cached serial_rb; 124 spinlock_t serial_lock; 125 wait_queue_head_t serial_io_wait; 126}; 127 128/* 129 * MD's 'extended' device 130 */ 131struct md_rdev { 132 struct list_head same_set; /* RAID devices within the same set */ 133 134 sector_t sectors; /* Device size (in 512bytes sectors) */ 135 struct mddev *mddev; /* RAID array if running */ 136 unsigned long last_events; /* IO event timestamp */ 137 138 /* 139 * If meta_bdev is non-NULL, it means that a separate device is 140 * being used to store the metadata (superblock/bitmap) which 141 * would otherwise be contained on the same device as the data (bdev). 142 */ 143 struct block_device *meta_bdev; 144 struct block_device *bdev; /* block device handle */ 145 struct file *bdev_file; /* Handle from open for bdev */ 146 147 struct page *sb_page, *bb_page; 148 int sb_loaded; 149 __u64 sb_events; 150 sector_t data_offset; /* start of data in array */ 151 sector_t new_data_offset;/* only relevant while reshaping */ 152 sector_t sb_start; /* offset of the super block (in 512byte sectors) */ 153 int sb_size; /* bytes in the superblock */ 154 int preferred_minor; /* autorun support */ 155 156 struct kobject kobj; 157 158 /* A device can be in one of three states based on two flags: 159 * Not working: faulty==1 in_sync==0 160 * Fully working: faulty==0 in_sync==1 161 * Working, but not 162 * in sync with array 163 * faulty==0 in_sync==0 164 * 165 * It can never have faulty==1, in_sync==1 166 * This reduces the burden of testing multiple flags in many cases 167 */ 168 169 unsigned long flags; /* bit set of 'enum flag_bits' bits. */ 170 wait_queue_head_t blocked_wait; 171 172 int desc_nr; /* descriptor index in the superblock */ 173 int raid_disk; /* role of device in array */ 174 int new_raid_disk; /* role that the device will have in 175 * the array after a level-change completes. 176 */ 177 int saved_raid_disk; /* role that device used to have in the 178 * array and could again if we did a partial 179 * resync from the bitmap 180 */ 181 union { 182 sector_t recovery_offset;/* If this device has been partially 183 * recovered, this is where we were 184 * up to. 185 */ 186 sector_t journal_tail; /* If this device is a journal device, 187 * this is the journal tail (journal 188 * recovery start point) 189 */ 190 }; 191 192 atomic_t nr_pending; /* number of pending requests. 193 * only maintained for arrays that 194 * support hot removal 195 */ 196 atomic_t read_errors; /* number of consecutive read errors that 197 * we have tried to ignore. 198 */ 199 time64_t last_read_error; /* monotonic time since our 200 * last read error 201 */ 202 atomic_t corrected_errors; /* number of corrected read errors, 203 * for reporting to userspace and storing 204 * in superblock. 205 */ 206 207 struct serial_in_rdev *serial; /* used for raid1 io serialization */ 208 209 struct kernfs_node *sysfs_state; /* handle for 'state' 210 * sysfs entry */ 211 /* handle for 'unacknowledged_bad_blocks' sysfs dentry */ 212 struct kernfs_node *sysfs_unack_badblocks; 213 /* handle for 'bad_blocks' sysfs dentry */ 214 struct kernfs_node *sysfs_badblocks; 215 struct badblocks badblocks; 216 217 struct { 218 short offset; /* Offset from superblock to start of PPL. 219 * Not used by external metadata. */ 220 unsigned int size; /* Size in sectors of the PPL space */ 221 sector_t sector; /* First sector of the PPL space */ 222 } ppl; 223}; 224enum flag_bits { 225 Faulty, /* device is known to have a fault */ 226 In_sync, /* device is in_sync with rest of array */ 227 Bitmap_sync, /* ..actually, not quite In_sync. Need a 228 * bitmap-based recovery to get fully in sync. 229 * The bit is only meaningful before device 230 * has been passed to pers->hot_add_disk. 231 */ 232 WriteMostly, /* Avoid reading if at all possible */ 233 AutoDetected, /* added by auto-detect */ 234 Blocked, /* An error occurred but has not yet 235 * been acknowledged by the metadata 236 * handler, so don't allow writes 237 * until it is cleared */ 238 WriteErrorSeen, /* A write error has been seen on this 239 * device 240 */ 241 FaultRecorded, /* Intermediate state for clearing 242 * Blocked. The Fault is/will-be 243 * recorded in the metadata, but that 244 * metadata hasn't been stored safely 245 * on disk yet. 246 */ 247 BlockedBadBlocks, /* A writer is blocked because they 248 * found an unacknowledged bad-block. 249 * This can safely be cleared at any 250 * time, and the writer will re-check. 251 * It may be set at any time, and at 252 * worst the writer will timeout and 253 * re-check. So setting it as 254 * accurately as possible is good, but 255 * not absolutely critical. 256 */ 257 WantReplacement, /* This device is a candidate to be 258 * hot-replaced, either because it has 259 * reported some faults, or because 260 * of explicit request. 261 */ 262 Replacement, /* This device is a replacement for 263 * a want_replacement device with same 264 * raid_disk number. 265 */ 266 Candidate, /* For clustered environments only: 267 * This device is seen locally but not 268 * by the whole cluster 269 */ 270 Journal, /* This device is used as journal for 271 * raid-5/6. 272 * Usually, this device should be faster 273 * than other devices in the array 274 */ 275 ClusterRemove, 276 ExternalBbl, /* External metadata provides bad 277 * block management for a disk 278 */ 279 FailFast, /* Minimal retries should be attempted on 280 * this device, so use REQ_FAILFAST_DEV. 281 * Also don't try to repair failed reads. 282 * It is expects that no bad block log 283 * is present. 284 */ 285 LastDev, /* Seems to be the last working dev as 286 * it didn't fail, so don't use FailFast 287 * any more for metadata 288 */ 289 CollisionCheck, /* 290 * check if there is collision between raid1 291 * serial bios. 292 */ 293 Nonrot, /* non-rotational device (SSD) */ 294}; 295 296static inline int is_badblock(struct md_rdev *rdev, sector_t s, sector_t sectors, 297 sector_t *first_bad, sector_t *bad_sectors) 298{ 299 if (unlikely(rdev->badblocks.count)) { 300 int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s, 301 sectors, 302 first_bad, bad_sectors); 303 if (rv) 304 *first_bad -= rdev->data_offset; 305 return rv; 306 } 307 return 0; 308} 309 310static inline int rdev_has_badblock(struct md_rdev *rdev, sector_t s, 311 int sectors) 312{ 313 sector_t first_bad; 314 sector_t bad_sectors; 315 316 return is_badblock(rdev, s, sectors, &first_bad, &bad_sectors); 317} 318 319extern bool rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 320 int is_new); 321extern void rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 322 int is_new); 323struct md_cluster_info; 324struct md_cluster_operations; 325 326/** 327 * enum mddev_flags - md device flags. 328 * @MD_ARRAY_FIRST_USE: First use of array, needs initialization. 329 * @MD_CLOSING: If set, we are closing the array, do not open it then. 330 * @MD_JOURNAL_CLEAN: A raid with journal is already clean. 331 * @MD_HAS_JOURNAL: The raid array has journal feature set. 332 * @MD_CLUSTER_RESYNC_LOCKED: cluster raid only, which means node, already took 333 * resync lock, need to release the lock. 334 * @MD_FAILFAST_SUPPORTED: Using MD_FAILFAST on metadata writes is supported as 335 * calls to md_error() will never cause the array to 336 * become failed. 337 * @MD_HAS_PPL: The raid array has PPL feature set. 338 * @MD_HAS_MULTIPLE_PPLS: The raid array has multiple PPLs feature set. 339 * @MD_NOT_READY: do_md_run() is active, so 'array_state', ust not report that 340 * array is ready yet. 341 * @MD_BROKEN: This is used to stop writes and mark array as failed. 342 * @MD_DELETED: This device is being deleted 343 * 344 * change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added 345 */ 346enum mddev_flags { 347 MD_ARRAY_FIRST_USE, 348 MD_CLOSING, 349 MD_JOURNAL_CLEAN, 350 MD_HAS_JOURNAL, 351 MD_CLUSTER_RESYNC_LOCKED, 352 MD_FAILFAST_SUPPORTED, 353 MD_HAS_PPL, 354 MD_HAS_MULTIPLE_PPLS, 355 MD_NOT_READY, 356 MD_BROKEN, 357 MD_DO_DELETE, 358 MD_DELETED, 359}; 360 361enum mddev_sb_flags { 362 MD_SB_CHANGE_DEVS, /* Some device status has changed */ 363 MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */ 364 MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */ 365 MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */ 366}; 367 368#define NR_SERIAL_INFOS 8 369/* record current range of serialize IOs */ 370struct serial_info { 371 struct rb_node node; 372 sector_t start; /* start sector of rb node */ 373 sector_t last; /* end sector of rb node */ 374 sector_t _subtree_last; /* highest sector in subtree of rb node */ 375}; 376 377/* 378 * mddev->curr_resync stores the current sector of the resync but 379 * also has some overloaded values. 380 */ 381enum { 382 /* No resync in progress */ 383 MD_RESYNC_NONE = 0, 384 /* Yielded to allow another conflicting resync to commence */ 385 MD_RESYNC_YIELDED = 1, 386 /* Delayed to check that there is no conflict with another sync */ 387 MD_RESYNC_DELAYED = 2, 388 /* Any value greater than or equal to this is in an active resync */ 389 MD_RESYNC_ACTIVE = 3, 390}; 391 392struct mddev { 393 void *private; 394 struct md_personality *pers; 395 dev_t unit; 396 int md_minor; 397 struct list_head disks; 398 unsigned long flags; 399 unsigned long sb_flags; 400 401 int suspended; 402 struct mutex suspend_mutex; 403 struct percpu_ref active_io; 404 int ro; 405 int sysfs_active; /* set when sysfs deletes 406 * are happening, so run/ 407 * takeover/stop are not safe 408 */ 409 struct gendisk *gendisk; /* mdraid gendisk */ 410 struct gendisk *dm_gendisk; /* dm-raid gendisk */ 411 412 struct kobject kobj; 413 int hold_active; 414#define UNTIL_IOCTL 1 415#define UNTIL_STOP 2 416 417 /* Superblock information */ 418 int major_version, 419 minor_version, 420 patch_version; 421 int persistent; 422 int external; /* metadata is 423 * managed externally */ 424 char metadata_type[17]; /* externally set*/ 425 int chunk_sectors; 426 time64_t ctime, utime; 427 int level, layout; 428 char clevel[16]; 429 int raid_disks; 430 int max_disks; 431 sector_t dev_sectors; /* used size of 432 * component devices */ 433 sector_t array_sectors; /* exported array size */ 434 int external_size; /* size managed 435 * externally */ 436 unsigned int logical_block_size; 437 __u64 events; 438 /* If the last 'event' was simply a clean->dirty transition, and 439 * we didn't write it to the spares, then it is safe and simple 440 * to just decrement the event count on a dirty->clean transition. 441 * So we record that possibility here. 442 */ 443 int can_decrease_events; 444 445 char uuid[16]; 446 447 /* If the array is being reshaped, we need to record the 448 * new shape and an indication of where we are up to. 449 * This is written to the superblock. 450 * If reshape_position is MaxSector, then no reshape is happening (yet). 451 */ 452 sector_t reshape_position; 453 int delta_disks, new_level, new_layout; 454 int new_chunk_sectors; 455 int reshape_backwards; 456 457 struct md_thread __rcu *thread; /* management thread */ 458 struct md_thread __rcu *sync_thread; /* doing resync or reconstruct */ 459 460 /* 461 * Set when a sync operation is started. It holds this value even 462 * when the sync thread is "frozen" (interrupted) or "idle" (stopped 463 * or finished). It is overwritten when a new sync operation is begun. 464 */ 465 enum sync_action last_sync_action; 466 sector_t curr_resync; /* last block scheduled */ 467 /* As resync requests can complete out of order, we cannot easily track 468 * how much resync has been completed. So we occasionally pause until 469 * everything completes, then set curr_resync_completed to curr_resync. 470 * As such it may be well behind the real resync mark, but it is a value 471 * we are certain of. 472 */ 473 sector_t curr_resync_completed; 474 unsigned long resync_mark; /* a recent timestamp */ 475 sector_t resync_mark_cnt;/* blocks written at resync_mark */ 476 sector_t curr_mark_cnt; /* blocks scheduled now */ 477 478 sector_t resync_max_sectors; /* may be set by personality */ 479 480 atomic64_t resync_mismatches; /* count of sectors where 481 * parity/replica mismatch found 482 */ 483 484 /* allow user-space to request suspension of IO to regions of the array */ 485 sector_t suspend_lo; 486 sector_t suspend_hi; 487 /* if zero, use the system-wide default */ 488 int sync_speed_min; 489 int sync_speed_max; 490 int sync_io_depth; 491 492 /* resync even though the same disks are shared among md-devices */ 493 int parallel_resync; 494 495 int ok_start_degraded; 496 497 unsigned long recovery; 498 /* If a RAID personality determines that recovery (of a particular 499 * device) will fail due to a read error on the source device, it 500 * takes a copy of this number and does not attempt recovery again 501 * until this number changes. 502 */ 503 int recovery_disabled; 504 505 int in_sync; /* know to not need resync */ 506 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so 507 * that we are never stopping an array while it is open. 508 * 'reconfig_mutex' protects all other reconfiguration. 509 * These locks are separate due to conflicting interactions 510 * with disk->open_mutex. 511 * Lock ordering is: 512 * reconfig_mutex -> disk->open_mutex 513 * disk->open_mutex -> open_mutex: e.g. __blkdev_get -> md_open 514 */ 515 struct mutex open_mutex; 516 struct mutex reconfig_mutex; 517 atomic_t active; /* general refcount */ 518 atomic_t openers; /* number of active opens */ 519 520 int changed; /* True if we might need to 521 * reread partition info */ 522 int degraded; /* whether md should consider 523 * adding a spare 524 */ 525 526 unsigned long normal_io_events; /* IO event timestamp */ 527 atomic_t recovery_active; /* blocks scheduled, but not written */ 528 wait_queue_head_t recovery_wait; 529 sector_t resync_offset; 530 sector_t resync_min; /* user requested sync 531 * starts here */ 532 sector_t resync_max; /* resync should pause 533 * when it gets here */ 534 535 struct kernfs_node *sysfs_state; /* handle for 'array_state' 536 * file in sysfs. 537 */ 538 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */ 539 struct kernfs_node *sysfs_completed; /*handle for 'sync_completed' */ 540 struct kernfs_node *sysfs_degraded; /*handle for 'degraded' */ 541 struct kernfs_node *sysfs_level; /*handle for 'level' */ 542 543 /* used for delayed sysfs removal */ 544 struct work_struct del_work; 545 /* used for register new sync thread */ 546 struct work_struct sync_work; 547 548 /* "lock" protects: 549 * flush_bio transition from NULL to !NULL 550 * rdev superblocks, events 551 * clearing MD_CHANGE_* 552 * in_sync - and related safemode and MD_CHANGE changes 553 * pers (also protected by reconfig_mutex and pending IO). 554 * clearing ->bitmap 555 * clearing ->bitmap_info.file 556 * changing ->resync_{min,max} 557 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max}) 558 */ 559 spinlock_t lock; 560 wait_queue_head_t sb_wait; /* for waiting on superblock updates */ 561 atomic_t pending_writes; /* number of active superblock writes */ 562 563 unsigned int safemode; /* if set, update "clean" superblock 564 * when no writes pending. 565 */ 566 unsigned int safemode_delay; 567 struct timer_list safemode_timer; 568 struct percpu_ref writes_pending; 569 int sync_checkers; /* # of threads checking writes_pending */ 570 571 enum md_submodule_id bitmap_id; 572 void *bitmap; /* the bitmap for the device */ 573 struct bitmap_operations *bitmap_ops; 574 struct { 575 struct file *file; /* the bitmap file */ 576 loff_t offset; /* offset from superblock of 577 * start of bitmap. May be 578 * negative, but not '0' 579 * For external metadata, offset 580 * from start of device. 581 */ 582 unsigned long space; /* space available at this offset */ 583 loff_t default_offset; /* this is the offset to use when 584 * hot-adding a bitmap. It should 585 * eventually be settable by sysfs. 586 */ 587 unsigned long default_space; /* space available at 588 * default offset */ 589 struct mutex mutex; 590 unsigned long chunksize; 591 unsigned long daemon_sleep; /* how many jiffies between updates? */ 592 unsigned long max_write_behind; /* write-behind mode */ 593 int external; 594 int nodes; /* Maximum number of nodes in the cluster */ 595 char cluster_name[64]; /* Name of the cluster */ 596 } bitmap_info; 597 598 atomic_t max_corr_read_errors; /* max read retries */ 599 struct list_head all_mddevs; 600 601 const struct attribute_group *to_remove; 602 603 struct bio_set bio_set; 604 struct bio_set sync_set; /* for sync operations like 605 * metadata and bitmap writes 606 */ 607 struct bio_set io_clone_set; 608 609 struct work_struct event_work; /* used by dm to report failure event */ 610 mempool_t *serial_info_pool; 611 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev); 612 struct md_cluster_info *cluster_info; 613 struct md_cluster_operations *cluster_ops; 614 unsigned int good_device_nr; /* good device num within cluster raid */ 615 unsigned int noio_flag; /* for memalloc scope API */ 616 617 /* 618 * Temporarily store rdev that will be finally removed when 619 * reconfig_mutex is unlocked, protected by reconfig_mutex. 620 */ 621 struct list_head deleting; 622 623 /* The sequence number for sync thread */ 624 atomic_t sync_seq; 625 626 bool has_superblocks:1; 627 bool fail_last_dev:1; 628 bool serialize_policy:1; 629}; 630 631enum recovery_flags { 632 /* flags for sync thread running status */ 633 634 /* 635 * set when one of sync action is set and new sync thread need to be 636 * registered, or just add/remove spares from conf. 637 */ 638 MD_RECOVERY_NEEDED, 639 /* sync thread is running, or about to be started */ 640 MD_RECOVERY_RUNNING, 641 /* sync thread needs to be aborted for some reason */ 642 MD_RECOVERY_INTR, 643 /* sync thread is done and is waiting to be unregistered */ 644 MD_RECOVERY_DONE, 645 /* running sync thread must abort immediately, and not restart */ 646 MD_RECOVERY_FROZEN, 647 /* waiting for pers->start() to finish */ 648 MD_RECOVERY_WAIT, 649 /* interrupted because io-error */ 650 MD_RECOVERY_ERROR, 651 652 /* flags determines sync action, see details in enum sync_action */ 653 654 /* if just this flag is set, action is resync. */ 655 MD_RECOVERY_SYNC, 656 /* 657 * paired with MD_RECOVERY_SYNC, if MD_RECOVERY_CHECK is not set, 658 * action is repair, means user requested resync. 659 */ 660 MD_RECOVERY_REQUESTED, 661 /* 662 * paired with MD_RECOVERY_SYNC and MD_RECOVERY_REQUESTED, action is 663 * check. 664 */ 665 MD_RECOVERY_CHECK, 666 /* recovery, or need to try it */ 667 MD_RECOVERY_RECOVER, 668 /* reshape */ 669 MD_RECOVERY_RESHAPE, 670 /* remote node is running resync thread */ 671 MD_RESYNCING_REMOTE, 672 /* raid456 lazy initial recover */ 673 MD_RECOVERY_LAZY_RECOVER, 674}; 675 676enum md_ro_state { 677 MD_RDWR, 678 MD_RDONLY, 679 MD_AUTO_READ, 680 MD_MAX_STATE 681}; 682 683static inline bool md_is_rdwr(struct mddev *mddev) 684{ 685 return (mddev->ro == MD_RDWR); 686} 687 688static inline bool reshape_interrupted(struct mddev *mddev) 689{ 690 /* reshape never start */ 691 if (mddev->reshape_position == MaxSector) 692 return false; 693 694 /* interrupted */ 695 if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) 696 return true; 697 698 /* running reshape will be interrupted soon. */ 699 if (test_bit(MD_RECOVERY_WAIT, &mddev->recovery) || 700 test_bit(MD_RECOVERY_INTR, &mddev->recovery) || 701 test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 702 return true; 703 704 return false; 705} 706 707static inline int __must_check mddev_lock(struct mddev *mddev) 708{ 709 int ret; 710 711 ret = mutex_lock_interruptible(&mddev->reconfig_mutex); 712 713 /* MD_DELETED is set in do_md_stop with reconfig_mutex. 714 * So check it here. 715 */ 716 if (!ret && test_bit(MD_DELETED, &mddev->flags)) { 717 ret = -ENODEV; 718 mutex_unlock(&mddev->reconfig_mutex); 719 } 720 721 return ret; 722} 723 724/* Sometimes we need to take the lock in a situation where 725 * failure due to interrupts is not acceptable. 726 * It doesn't need to check MD_DELETED here, the owner which 727 * holds the lock here can't be stopped. And all paths can't 728 * call this function after do_md_stop. 729 */ 730static inline void mddev_lock_nointr(struct mddev *mddev) 731{ 732 mutex_lock(&mddev->reconfig_mutex); 733} 734 735static inline int mddev_trylock(struct mddev *mddev) 736{ 737 int ret; 738 739 ret = mutex_trylock(&mddev->reconfig_mutex); 740 if (ret && test_bit(MD_DELETED, &mddev->flags)) { 741 ret = 0; 742 mutex_unlock(&mddev->reconfig_mutex); 743 } 744 return ret; 745} 746extern void mddev_unlock(struct mddev *mddev); 747 748struct md_personality 749{ 750 struct md_submodule_head head; 751 752 bool __must_check (*make_request)(struct mddev *mddev, struct bio *bio); 753 /* 754 * start up works that do NOT require md_thread. tasks that 755 * requires md_thread should go into start() 756 */ 757 int (*run)(struct mddev *mddev); 758 /* start up works that require md threads */ 759 int (*start)(struct mddev *mddev); 760 void (*free)(struct mddev *mddev, void *priv); 761 void (*status)(struct seq_file *seq, struct mddev *mddev); 762 /* error_handler must set ->faulty and clear ->in_sync 763 * if appropriate, and should abort recovery if needed 764 */ 765 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev); 766 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev); 767 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev); 768 int (*spare_active) (struct mddev *mddev); 769 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, 770 sector_t max_sector, int *skipped); 771 int (*resize) (struct mddev *mddev, sector_t sectors); 772 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks); 773 int (*check_reshape) (struct mddev *mddev); 774 int (*start_reshape) (struct mddev *mddev); 775 void (*finish_reshape) (struct mddev *mddev); 776 void (*update_reshape_pos) (struct mddev *mddev); 777 void (*prepare_suspend) (struct mddev *mddev); 778 /* quiesce suspends or resumes internal processing. 779 * 1 - stop new actions and wait for action io to complete 780 * 0 - return to normal behaviour 781 */ 782 void (*quiesce) (struct mddev *mddev, int quiesce); 783 /* takeover is used to transition an array from one 784 * personality to another. The new personality must be able 785 * to handle the data in the current layout. 786 * e.g. 2drive raid1 -> 2drive raid5 787 * ndrive raid5 -> degraded n+1drive raid6 with special layout 788 * If the takeover succeeds, a new 'private' structure is returned. 789 * This needs to be installed and then ->run used to activate the 790 * array. 791 */ 792 void *(*takeover) (struct mddev *mddev); 793 /* Changes the consistency policy of an active array. */ 794 int (*change_consistency_policy)(struct mddev *mddev, const char *buf); 795 /* convert io ranges from array to bitmap */ 796 void (*bitmap_sector)(struct mddev *mddev, sector_t *offset, 797 unsigned long *sectors); 798}; 799 800struct md_sysfs_entry { 801 struct attribute attr; 802 ssize_t (*show)(struct mddev *, char *); 803 ssize_t (*store)(struct mddev *, const char *, size_t); 804}; 805 806static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name) 807{ 808 if (sd) 809 return sysfs_get_dirent(sd, name); 810 return sd; 811} 812static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd) 813{ 814 if (sd) 815 sysfs_notify_dirent(sd); 816} 817 818static inline char * mdname (struct mddev * mddev) 819{ 820 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; 821} 822 823static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev) 824{ 825 char nm[20]; 826 if (!test_bit(Replacement, &rdev->flags) && 827 !test_bit(Journal, &rdev->flags) && 828 mddev->kobj.sd) { 829 sprintf(nm, "rd%d", rdev->raid_disk); 830 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); 831 } else 832 return 0; 833} 834 835static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev) 836{ 837 char nm[20]; 838 if (!test_bit(Replacement, &rdev->flags) && 839 !test_bit(Journal, &rdev->flags) && 840 mddev->kobj.sd) { 841 sprintf(nm, "rd%d", rdev->raid_disk); 842 sysfs_remove_link(&mddev->kobj, nm); 843 } 844} 845 846/* 847 * iterates through some rdev ringlist. It's safe to remove the 848 * current 'rdev'. Dont touch 'tmp' though. 849 */ 850#define rdev_for_each_list(rdev, tmp, head) \ 851 list_for_each_entry_safe(rdev, tmp, head, same_set) 852 853/* 854 * iterates through the 'same array disks' ringlist 855 */ 856#define rdev_for_each(rdev, mddev) \ 857 list_for_each_entry(rdev, &((mddev)->disks), same_set) 858 859#define rdev_for_each_safe(rdev, tmp, mddev) \ 860 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) 861 862#define rdev_for_each_rcu(rdev, mddev) \ 863 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) 864 865struct md_thread { 866 void (*run) (struct md_thread *thread); 867 struct mddev *mddev; 868 wait_queue_head_t wqueue; 869 unsigned long flags; 870 struct task_struct *tsk; 871 unsigned long timeout; 872 void *private; 873}; 874 875struct md_io_clone { 876 struct mddev *mddev; 877 struct bio *orig_bio; 878 unsigned long start_time; 879 sector_t offset; 880 unsigned long sectors; 881 enum stat_group rw; 882 struct bio bio_clone; 883}; 884 885#define THREAD_WAKEUP 0 886 887#define md_wakeup_thread(thread) do { \ 888 rcu_read_lock(); \ 889 __md_wakeup_thread(thread); \ 890 rcu_read_unlock(); \ 891} while (0) 892 893static inline void safe_put_page(struct page *p) 894{ 895 if (p) put_page(p); 896} 897 898int register_md_submodule(struct md_submodule_head *msh); 899void unregister_md_submodule(struct md_submodule_head *msh); 900 901extern struct md_thread *md_register_thread( 902 void (*run)(struct md_thread *thread), 903 struct mddev *mddev, 904 const char *name); 905extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp); 906extern void __md_wakeup_thread(struct md_thread __rcu *thread); 907extern void md_check_recovery(struct mddev *mddev); 908extern void md_reap_sync_thread(struct mddev *mddev); 909extern enum sync_action md_sync_action(struct mddev *mddev); 910extern enum sync_action md_sync_action_by_name(const char *page); 911extern const char *md_sync_action_name(enum sync_action action); 912extern void md_write_start(struct mddev *mddev, struct bio *bi); 913extern void md_write_inc(struct mddev *mddev, struct bio *bi); 914extern void md_write_end(struct mddev *mddev); 915extern void md_done_sync(struct mddev *mddev, int blocks, int ok); 916extern void md_error(struct mddev *mddev, struct md_rdev *rdev); 917extern void md_finish_reshape(struct mddev *mddev); 918void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev, 919 struct bio *bio, sector_t start, sector_t size); 920void md_account_bio(struct mddev *mddev, struct bio **bio); 921void md_free_cloned_bio(struct bio *bio); 922 923extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio); 924void md_write_metadata(struct mddev *mddev, struct md_rdev *rdev, 925 sector_t sector, int size, struct page *page, 926 unsigned int offset); 927extern int md_super_wait(struct mddev *mddev); 928extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, 929 struct page *page, blk_opf_t opf, bool metadata_op); 930extern void md_do_sync(struct md_thread *thread); 931extern void md_new_event(void); 932extern void md_allow_write(struct mddev *mddev); 933extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); 934extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); 935extern int md_check_no_bitmap(struct mddev *mddev); 936extern int md_integrity_register(struct mddev *mddev); 937extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale); 938 939extern int mddev_init(struct mddev *mddev); 940extern void mddev_destroy(struct mddev *mddev); 941void md_init_stacking_limits(struct queue_limits *lim); 942struct mddev *md_alloc(dev_t dev, char *name); 943void mddev_put(struct mddev *mddev); 944extern int md_run(struct mddev *mddev); 945extern int md_start(struct mddev *mddev); 946extern void md_stop(struct mddev *mddev); 947extern void md_stop_writes(struct mddev *mddev); 948extern int md_rdev_init(struct md_rdev *rdev); 949extern void md_rdev_clear(struct md_rdev *rdev); 950 951extern bool md_handle_request(struct mddev *mddev, struct bio *bio); 952extern int mddev_suspend(struct mddev *mddev, bool interruptible); 953extern void mddev_resume(struct mddev *mddev); 954extern void md_idle_sync_thread(struct mddev *mddev); 955extern void md_frozen_sync_thread(struct mddev *mddev); 956extern void md_unfrozen_sync_thread(struct mddev *mddev); 957 958extern void md_update_sb(struct mddev *mddev, int force); 959extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev); 960extern void mddev_destroy_serial_pool(struct mddev *mddev, 961 struct md_rdev *rdev); 962struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr); 963struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev); 964 965static inline bool is_rdev_broken(struct md_rdev *rdev) 966{ 967 return !disk_live(rdev->bdev->bd_disk); 968} 969 970static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev) 971{ 972 int faulty = test_bit(Faulty, &rdev->flags); 973 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) { 974 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 975 md_wakeup_thread(mddev->thread); 976 } 977} 978 979static inline int mddev_is_clustered(struct mddev *mddev) 980{ 981 return mddev->cluster_info && mddev->bitmap_info.nodes > 1; 982} 983 984/* clear unsupported mddev_flags */ 985static inline void mddev_clear_unsupported_flags(struct mddev *mddev, 986 unsigned long unsupported_flags) 987{ 988 mddev->flags &= ~unsupported_flags; 989} 990 991static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio) 992{ 993 if (bio_op(bio) == REQ_OP_WRITE_ZEROES && 994 !bio->bi_bdev->bd_disk->queue->limits.max_write_zeroes_sectors) 995 mddev->gendisk->queue->limits.max_write_zeroes_sectors = 0; 996} 997 998static inline int mddev_suspend_and_lock(struct mddev *mddev) 999{ 1000 int ret; 1001 1002 ret = mddev_suspend(mddev, true); 1003 if (ret) 1004 return ret; 1005 1006 ret = mddev_lock(mddev); 1007 if (ret) 1008 mddev_resume(mddev); 1009 1010 return ret; 1011} 1012 1013static inline void mddev_suspend_and_lock_nointr(struct mddev *mddev) 1014{ 1015 mddev_suspend(mddev, false); 1016 mutex_lock(&mddev->reconfig_mutex); 1017} 1018 1019static inline void mddev_unlock_and_resume(struct mddev *mddev) 1020{ 1021 mddev_unlock(mddev); 1022 mddev_resume(mddev); 1023} 1024 1025struct mdu_array_info_s; 1026struct mdu_disk_info_s; 1027 1028extern int mdp_major; 1029void md_autostart_arrays(int part); 1030int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info); 1031int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info); 1032int do_md_run(struct mddev *mddev); 1033#define MDDEV_STACK_INTEGRITY (1u << 0) 1034int mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim, 1035 unsigned int flags); 1036int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev); 1037void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes); 1038 1039extern const struct block_device_operations md_fops; 1040 1041/* 1042 * MD devices can be used undeneath by DM, in which case ->gendisk is NULL. 1043 */ 1044static inline bool mddev_is_dm(struct mddev *mddev) 1045{ 1046 return !mddev->gendisk; 1047} 1048 1049static inline bool raid_is_456(struct mddev *mddev) 1050{ 1051 return mddev->level == ID_RAID4 || mddev->level == ID_RAID5 || 1052 mddev->level == ID_RAID6; 1053} 1054 1055static inline void mddev_trace_remap(struct mddev *mddev, struct bio *bio, 1056 sector_t sector) 1057{ 1058 if (!mddev_is_dm(mddev)) 1059 trace_block_bio_remap(bio, disk_devt(mddev->gendisk), sector); 1060} 1061 1062static inline bool rdev_blocked(struct md_rdev *rdev) 1063{ 1064 /* 1065 * Blocked will be set by error handler and cleared by daemon after 1066 * updating superblock, meanwhile write IO should be blocked to prevent 1067 * reading old data after power failure. 1068 */ 1069 if (test_bit(Blocked, &rdev->flags)) 1070 return true; 1071 1072 /* 1073 * Faulty device should not be accessed anymore, there is no need to 1074 * wait for bad block to be acknowledged. 1075 */ 1076 if (test_bit(Faulty, &rdev->flags)) 1077 return false; 1078 1079 /* rdev is blocked by badblocks. */ 1080 if (test_bit(BlockedBadBlocks, &rdev->flags)) 1081 return true; 1082 1083 return false; 1084} 1085 1086#define mddev_add_trace_msg(mddev, fmt, args...) \ 1087do { \ 1088 if (!mddev_is_dm(mddev)) \ 1089 blk_add_trace_msg((mddev)->gendisk->queue, fmt, ##args); \ 1090} while (0) 1091 1092#endif /* _MD_MD_H */
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