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