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