1 /* 2 md.h : kernel internal structure of the Linux MD driver 3 Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 2, or (at your option) 8 any later version. 9 10 You should have received a copy of the GNU General Public License 11 (for example /usr/src/linux/COPYING); if not, write to the Free 12 Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 13 */ 14 15 #ifndef _MD_MD_H 16 #define _MD_MD_H 17 18 #include <linux/blkdev.h> 19 #include <linux/backing-dev.h> 20 #include <linux/badblocks.h> 21 #include <linux/kobject.h> 22 #include <linux/list.h> 23 #include <linux/mm.h> 24 #include <linux/mutex.h> 25 #include <linux/timer.h> 26 #include <linux/wait.h> 27 #include <linux/workqueue.h> 28 #include "md-cluster.h" 29 30 #define MaxSector (~(sector_t)0) 31 32 /* 33 * These flags should really be called "NO_RETRY" rather than 34 * "FAILFAST" because they don't make any promise about time lapse, 35 * only about the number of retries, which will be zero. 36 * REQ_FAILFAST_DRIVER is not included because 37 * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.") 38 * seems to suggest that the errors it avoids retrying should usually 39 * be retried. 40 */ 41 #define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT) 42 /* 43 * MD's 'extended' device 44 */ 45 struct md_rdev { 46 struct list_head same_set; /* RAID devices within the same set */ 47 48 sector_t sectors; /* Device size (in 512bytes sectors) */ 49 struct mddev *mddev; /* RAID array if running */ 50 int last_events; /* IO event timestamp */ 51 52 /* 53 * If meta_bdev is non-NULL, it means that a separate device is 54 * being used to store the metadata (superblock/bitmap) which 55 * would otherwise be contained on the same device as the data (bdev). 56 */ 57 struct block_device *meta_bdev; 58 struct block_device *bdev; /* block device handle */ 59 60 struct page *sb_page, *bb_page; 61 int sb_loaded; 62 __u64 sb_events; 63 sector_t data_offset; /* start of data in array */ 64 sector_t new_data_offset;/* only relevant while reshaping */ 65 sector_t sb_start; /* offset of the super block (in 512byte sectors) */ 66 int sb_size; /* bytes in the superblock */ 67 int preferred_minor; /* autorun support */ 68 69 struct kobject kobj; 70 71 /* A device can be in one of three states based on two flags: 72 * Not working: faulty==1 in_sync==0 73 * Fully working: faulty==0 in_sync==1 74 * Working, but not 75 * in sync with array 76 * faulty==0 in_sync==0 77 * 78 * It can never have faulty==1, in_sync==1 79 * This reduces the burden of testing multiple flags in many cases 80 */ 81 82 unsigned long flags; /* bit set of 'enum flag_bits' bits. */ 83 wait_queue_head_t blocked_wait; 84 85 int desc_nr; /* descriptor index in the superblock */ 86 int raid_disk; /* role of device in array */ 87 int new_raid_disk; /* role that the device will have in 88 * the array after a level-change completes. 89 */ 90 int saved_raid_disk; /* role that device used to have in the 91 * array and could again if we did a partial 92 * resync from the bitmap 93 */ 94 union { 95 sector_t recovery_offset;/* If this device has been partially 96 * recovered, this is where we were 97 * up to. 98 */ 99 sector_t journal_tail; /* If this device is a journal device, 100 * this is the journal tail (journal 101 * recovery start point) 102 */ 103 }; 104 105 atomic_t nr_pending; /* number of pending requests. 106 * only maintained for arrays that 107 * support hot removal 108 */ 109 atomic_t read_errors; /* number of consecutive read errors that 110 * we have tried to ignore. 111 */ 112 time64_t last_read_error; /* monotonic time since our 113 * last read error 114 */ 115 atomic_t corrected_errors; /* number of corrected read errors, 116 * for reporting to userspace and storing 117 * in superblock. 118 */ 119 struct work_struct del_work; /* used for delayed sysfs removal */ 120 121 struct kernfs_node *sysfs_state; /* handle for 'state' 122 * sysfs entry */ 123 124 struct badblocks badblocks; 125 126 struct { 127 short offset; /* Offset from superblock to start of PPL. 128 * Not used by external metadata. */ 129 unsigned int size; /* Size in sectors of the PPL space */ 130 sector_t sector; /* First sector of the PPL space */ 131 } ppl; 132 }; 133 enum flag_bits { 134 Faulty, /* device is known to have a fault */ 135 In_sync, /* device is in_sync with rest of array */ 136 Bitmap_sync, /* ..actually, not quite In_sync. Need a 137 * bitmap-based recovery to get fully in sync. 138 * The bit is only meaningful before device 139 * has been passed to pers->hot_add_disk. 140 */ 141 WriteMostly, /* Avoid reading if at all possible */ 142 AutoDetected, /* added by auto-detect */ 143 Blocked, /* An error occurred but has not yet 144 * been acknowledged by the metadata 145 * handler, so don't allow writes 146 * until it is cleared */ 147 WriteErrorSeen, /* A write error has been seen on this 148 * device 149 */ 150 FaultRecorded, /* Intermediate state for clearing 151 * Blocked. The Fault is/will-be 152 * recorded in the metadata, but that 153 * metadata hasn't been stored safely 154 * on disk yet. 155 */ 156 BlockedBadBlocks, /* A writer is blocked because they 157 * found an unacknowledged bad-block. 158 * This can safely be cleared at any 159 * time, and the writer will re-check. 160 * It may be set at any time, and at 161 * worst the writer will timeout and 162 * re-check. So setting it as 163 * accurately as possible is good, but 164 * not absolutely critical. 165 */ 166 WantReplacement, /* This device is a candidate to be 167 * hot-replaced, either because it has 168 * reported some faults, or because 169 * of explicit request. 170 */ 171 Replacement, /* This device is a replacement for 172 * a want_replacement device with same 173 * raid_disk number. 174 */ 175 Candidate, /* For clustered environments only: 176 * This device is seen locally but not 177 * by the whole cluster 178 */ 179 Journal, /* This device is used as journal for 180 * raid-5/6. 181 * Usually, this device should be faster 182 * than other devices in the array 183 */ 184 ClusterRemove, 185 RemoveSynchronized, /* synchronize_rcu() was called after 186 * this device was known to be faulty, 187 * so it is safe to remove without 188 * another synchronize_rcu() call. 189 */ 190 ExternalBbl, /* External metadata provides bad 191 * block management for a disk 192 */ 193 FailFast, /* Minimal retries should be attempted on 194 * this device, so use REQ_FAILFAST_DEV. 195 * Also don't try to repair failed reads. 196 * It is expects that no bad block log 197 * is present. 198 */ 199 LastDev, /* Seems to be the last working dev as 200 * it didn't fail, so don't use FailFast 201 * any more for metadata 202 */ 203 }; 204 205 static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors, 206 sector_t *first_bad, int *bad_sectors) 207 { 208 if (unlikely(rdev->badblocks.count)) { 209 int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s, 210 sectors, 211 first_bad, bad_sectors); 212 if (rv) 213 *first_bad -= rdev->data_offset; 214 return rv; 215 } 216 return 0; 217 } 218 extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 219 int is_new); 220 extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 221 int is_new); 222 struct md_cluster_info; 223 224 /* change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added */ 225 enum mddev_flags { 226 MD_ARRAY_FIRST_USE, /* First use of array, needs initialization */ 227 MD_CLOSING, /* If set, we are closing the array, do not open 228 * it then */ 229 MD_JOURNAL_CLEAN, /* A raid with journal is already clean */ 230 MD_HAS_JOURNAL, /* The raid array has journal feature set */ 231 MD_CLUSTER_RESYNC_LOCKED, /* cluster raid only, which means node 232 * already took resync lock, need to 233 * release the lock */ 234 MD_FAILFAST_SUPPORTED, /* Using MD_FAILFAST on metadata writes is 235 * supported as calls to md_error() will 236 * never cause the array to become failed. 237 */ 238 MD_HAS_PPL, /* The raid array has PPL feature set */ 239 MD_HAS_MULTIPLE_PPLS, /* The raid array has multiple PPLs feature set */ 240 MD_ALLOW_SB_UPDATE, /* md_check_recovery is allowed to update 241 * the metadata without taking reconfig_mutex. 242 */ 243 MD_UPDATING_SB, /* md_check_recovery is updating the metadata 244 * without explicitly holding reconfig_mutex. 245 */ 246 }; 247 248 enum mddev_sb_flags { 249 MD_SB_CHANGE_DEVS, /* Some device status has changed */ 250 MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */ 251 MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */ 252 MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */ 253 }; 254 255 struct mddev { 256 void *private; 257 struct md_personality *pers; 258 dev_t unit; 259 int md_minor; 260 struct list_head disks; 261 unsigned long flags; 262 unsigned long sb_flags; 263 264 int suspended; 265 atomic_t active_io; 266 int ro; 267 int sysfs_active; /* set when sysfs deletes 268 * are happening, so run/ 269 * takeover/stop are not safe 270 */ 271 struct gendisk *gendisk; 272 273 struct kobject kobj; 274 int hold_active; 275 #define UNTIL_IOCTL 1 276 #define UNTIL_STOP 2 277 278 /* Superblock information */ 279 int major_version, 280 minor_version, 281 patch_version; 282 int persistent; 283 int external; /* metadata is 284 * managed externally */ 285 char metadata_type[17]; /* externally set*/ 286 int chunk_sectors; 287 time64_t ctime, utime; 288 int level, layout; 289 char clevel[16]; 290 int raid_disks; 291 int max_disks; 292 sector_t dev_sectors; /* used size of 293 * component devices */ 294 sector_t array_sectors; /* exported array size */ 295 int external_size; /* size managed 296 * externally */ 297 __u64 events; 298 /* If the last 'event' was simply a clean->dirty transition, and 299 * we didn't write it to the spares, then it is safe and simple 300 * to just decrement the event count on a dirty->clean transition. 301 * So we record that possibility here. 302 */ 303 int can_decrease_events; 304 305 char uuid[16]; 306 307 /* If the array is being reshaped, we need to record the 308 * new shape and an indication of where we are up to. 309 * This is written to the superblock. 310 * If reshape_position is MaxSector, then no reshape is happening (yet). 311 */ 312 sector_t reshape_position; 313 int delta_disks, new_level, new_layout; 314 int new_chunk_sectors; 315 int reshape_backwards; 316 317 struct md_thread *thread; /* management thread */ 318 struct md_thread *sync_thread; /* doing resync or reconstruct */ 319 320 /* 'last_sync_action' is initialized to "none". It is set when a 321 * sync operation (i.e "data-check", "requested-resync", "resync", 322 * "recovery", or "reshape") is started. It holds this value even 323 * when the sync thread is "frozen" (interrupted) or "idle" (stopped 324 * or finished). It is overwritten when a new sync operation is begun. 325 */ 326 char *last_sync_action; 327 sector_t curr_resync; /* last block scheduled */ 328 /* As resync requests can complete out of order, we cannot easily track 329 * how much resync has been completed. So we occasionally pause until 330 * everything completes, then set curr_resync_completed to curr_resync. 331 * As such it may be well behind the real resync mark, but it is a value 332 * we are certain of. 333 */ 334 sector_t curr_resync_completed; 335 unsigned long resync_mark; /* a recent timestamp */ 336 sector_t resync_mark_cnt;/* blocks written at resync_mark */ 337 sector_t curr_mark_cnt; /* blocks scheduled now */ 338 339 sector_t resync_max_sectors; /* may be set by personality */ 340 341 atomic64_t resync_mismatches; /* count of sectors where 342 * parity/replica mismatch found 343 */ 344 345 /* allow user-space to request suspension of IO to regions of the array */ 346 sector_t suspend_lo; 347 sector_t suspend_hi; 348 /* if zero, use the system-wide default */ 349 int sync_speed_min; 350 int sync_speed_max; 351 352 /* resync even though the same disks are shared among md-devices */ 353 int parallel_resync; 354 355 int ok_start_degraded; 356 357 unsigned long recovery; 358 /* If a RAID personality determines that recovery (of a particular 359 * device) will fail due to a read error on the source device, it 360 * takes a copy of this number and does not attempt recovery again 361 * until this number changes. 362 */ 363 int recovery_disabled; 364 365 int in_sync; /* know to not need resync */ 366 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so 367 * that we are never stopping an array while it is open. 368 * 'reconfig_mutex' protects all other reconfiguration. 369 * These locks are separate due to conflicting interactions 370 * with bdev->bd_mutex. 371 * Lock ordering is: 372 * reconfig_mutex -> bd_mutex : e.g. do_md_run -> revalidate_disk 373 * bd_mutex -> open_mutex: e.g. __blkdev_get -> md_open 374 */ 375 struct mutex open_mutex; 376 struct mutex reconfig_mutex; 377 atomic_t active; /* general refcount */ 378 atomic_t openers; /* number of active opens */ 379 380 int changed; /* True if we might need to 381 * reread partition info */ 382 int degraded; /* whether md should consider 383 * adding a spare 384 */ 385 386 atomic_t recovery_active; /* blocks scheduled, but not written */ 387 wait_queue_head_t recovery_wait; 388 sector_t recovery_cp; 389 sector_t resync_min; /* user requested sync 390 * starts here */ 391 sector_t resync_max; /* resync should pause 392 * when it gets here */ 393 394 struct kernfs_node *sysfs_state; /* handle for 'array_state' 395 * file in sysfs. 396 */ 397 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */ 398 399 struct work_struct del_work; /* used for delayed sysfs removal */ 400 401 /* "lock" protects: 402 * flush_bio transition from NULL to !NULL 403 * rdev superblocks, events 404 * clearing MD_CHANGE_* 405 * in_sync - and related safemode and MD_CHANGE changes 406 * pers (also protected by reconfig_mutex and pending IO). 407 * clearing ->bitmap 408 * clearing ->bitmap_info.file 409 * changing ->resync_{min,max} 410 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max}) 411 */ 412 spinlock_t lock; 413 wait_queue_head_t sb_wait; /* for waiting on superblock updates */ 414 atomic_t pending_writes; /* number of active superblock writes */ 415 416 unsigned int safemode; /* if set, update "clean" superblock 417 * when no writes pending. 418 */ 419 unsigned int safemode_delay; 420 struct timer_list safemode_timer; 421 struct percpu_ref writes_pending; 422 int sync_checkers; /* # of threads checking writes_pending */ 423 struct request_queue *queue; /* for plugging ... */ 424 425 struct bitmap *bitmap; /* the bitmap for the device */ 426 struct { 427 struct file *file; /* the bitmap file */ 428 loff_t offset; /* offset from superblock of 429 * start of bitmap. May be 430 * negative, but not '0' 431 * For external metadata, offset 432 * from start of device. 433 */ 434 unsigned long space; /* space available at this offset */ 435 loff_t default_offset; /* this is the offset to use when 436 * hot-adding a bitmap. It should 437 * eventually be settable by sysfs. 438 */ 439 unsigned long default_space; /* space available at 440 * default offset */ 441 struct mutex mutex; 442 unsigned long chunksize; 443 unsigned long daemon_sleep; /* how many jiffies between updates? */ 444 unsigned long max_write_behind; /* write-behind mode */ 445 int external; 446 int nodes; /* Maximum number of nodes in the cluster */ 447 char cluster_name[64]; /* Name of the cluster */ 448 } bitmap_info; 449 450 atomic_t max_corr_read_errors; /* max read retries */ 451 struct list_head all_mddevs; 452 453 struct attribute_group *to_remove; 454 455 struct bio_set *bio_set; 456 struct bio_set *sync_set; /* for sync operations like 457 * metadata and bitmap writes 458 */ 459 460 /* Generic flush handling. 461 * The last to finish preflush schedules a worker to submit 462 * the rest of the request (without the REQ_PREFLUSH flag). 463 */ 464 struct bio *flush_bio; 465 atomic_t flush_pending; 466 struct work_struct flush_work; 467 struct work_struct event_work; /* used by dm to report failure event */ 468 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev); 469 struct md_cluster_info *cluster_info; 470 unsigned int good_device_nr; /* good device num within cluster raid */ 471 472 bool has_superblocks:1; 473 }; 474 475 enum recovery_flags { 476 /* 477 * If neither SYNC or RESHAPE are set, then it is a recovery. 478 */ 479 MD_RECOVERY_RUNNING, /* a thread is running, or about to be started */ 480 MD_RECOVERY_SYNC, /* actually doing a resync, not a recovery */ 481 MD_RECOVERY_RECOVER, /* doing recovery, or need to try it. */ 482 MD_RECOVERY_INTR, /* resync needs to be aborted for some reason */ 483 MD_RECOVERY_DONE, /* thread is done and is waiting to be reaped */ 484 MD_RECOVERY_NEEDED, /* we might need to start a resync/recover */ 485 MD_RECOVERY_REQUESTED, /* user-space has requested a sync (used with SYNC) */ 486 MD_RECOVERY_CHECK, /* user-space request for check-only, no repair */ 487 MD_RECOVERY_RESHAPE, /* A reshape is happening */ 488 MD_RECOVERY_FROZEN, /* User request to abort, and not restart, any action */ 489 MD_RECOVERY_ERROR, /* sync-action interrupted because io-error */ 490 MD_RECOVERY_WAIT, /* waiting for pers->start() to finish */ 491 }; 492 493 static inline int __must_check mddev_lock(struct mddev *mddev) 494 { 495 return mutex_lock_interruptible(&mddev->reconfig_mutex); 496 } 497 498 /* Sometimes we need to take the lock in a situation where 499 * failure due to interrupts is not acceptable. 500 */ 501 static inline void mddev_lock_nointr(struct mddev *mddev) 502 { 503 mutex_lock(&mddev->reconfig_mutex); 504 } 505 506 static inline int mddev_trylock(struct mddev *mddev) 507 { 508 return mutex_trylock(&mddev->reconfig_mutex); 509 } 510 extern void mddev_unlock(struct mddev *mddev); 511 512 static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors) 513 { 514 atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io); 515 } 516 517 static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors) 518 { 519 atomic_add(nr_sectors, &bio->bi_disk->sync_io); 520 } 521 522 struct md_personality 523 { 524 char *name; 525 int level; 526 struct list_head list; 527 struct module *owner; 528 bool (*make_request)(struct mddev *mddev, struct bio *bio); 529 /* 530 * start up works that do NOT require md_thread. tasks that 531 * requires md_thread should go into start() 532 */ 533 int (*run)(struct mddev *mddev); 534 /* start up works that require md threads */ 535 int (*start)(struct mddev *mddev); 536 void (*free)(struct mddev *mddev, void *priv); 537 void (*status)(struct seq_file *seq, struct mddev *mddev); 538 /* error_handler must set ->faulty and clear ->in_sync 539 * if appropriate, and should abort recovery if needed 540 */ 541 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev); 542 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev); 543 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev); 544 int (*spare_active) (struct mddev *mddev); 545 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped); 546 int (*resize) (struct mddev *mddev, sector_t sectors); 547 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks); 548 int (*check_reshape) (struct mddev *mddev); 549 int (*start_reshape) (struct mddev *mddev); 550 void (*finish_reshape) (struct mddev *mddev); 551 /* quiesce suspends or resumes internal processing. 552 * 1 - stop new actions and wait for action io to complete 553 * 0 - return to normal behaviour 554 */ 555 void (*quiesce) (struct mddev *mddev, int quiesce); 556 /* takeover is used to transition an array from one 557 * personality to another. The new personality must be able 558 * to handle the data in the current layout. 559 * e.g. 2drive raid1 -> 2drive raid5 560 * ndrive raid5 -> degraded n+1drive raid6 with special layout 561 * If the takeover succeeds, a new 'private' structure is returned. 562 * This needs to be installed and then ->run used to activate the 563 * array. 564 */ 565 void *(*takeover) (struct mddev *mddev); 566 /* congested implements bdi.congested_fn(). 567 * Will not be called while array is 'suspended' */ 568 int (*congested)(struct mddev *mddev, int bits); 569 /* Changes the consistency policy of an active array. */ 570 int (*change_consistency_policy)(struct mddev *mddev, const char *buf); 571 }; 572 573 struct md_sysfs_entry { 574 struct attribute attr; 575 ssize_t (*show)(struct mddev *, char *); 576 ssize_t (*store)(struct mddev *, const char *, size_t); 577 }; 578 extern struct attribute_group md_bitmap_group; 579 580 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name) 581 { 582 if (sd) 583 return sysfs_get_dirent(sd, name); 584 return sd; 585 } 586 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd) 587 { 588 if (sd) 589 sysfs_notify_dirent(sd); 590 } 591 592 static inline char * mdname (struct mddev * mddev) 593 { 594 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; 595 } 596 597 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev) 598 { 599 char nm[20]; 600 if (!test_bit(Replacement, &rdev->flags) && 601 !test_bit(Journal, &rdev->flags) && 602 mddev->kobj.sd) { 603 sprintf(nm, "rd%d", rdev->raid_disk); 604 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); 605 } else 606 return 0; 607 } 608 609 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev) 610 { 611 char nm[20]; 612 if (!test_bit(Replacement, &rdev->flags) && 613 !test_bit(Journal, &rdev->flags) && 614 mddev->kobj.sd) { 615 sprintf(nm, "rd%d", rdev->raid_disk); 616 sysfs_remove_link(&mddev->kobj, nm); 617 } 618 } 619 620 /* 621 * iterates through some rdev ringlist. It's safe to remove the 622 * current 'rdev'. Dont touch 'tmp' though. 623 */ 624 #define rdev_for_each_list(rdev, tmp, head) \ 625 list_for_each_entry_safe(rdev, tmp, head, same_set) 626 627 /* 628 * iterates through the 'same array disks' ringlist 629 */ 630 #define rdev_for_each(rdev, mddev) \ 631 list_for_each_entry(rdev, &((mddev)->disks), same_set) 632 633 #define rdev_for_each_safe(rdev, tmp, mddev) \ 634 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) 635 636 #define rdev_for_each_rcu(rdev, mddev) \ 637 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) 638 639 struct md_thread { 640 void (*run) (struct md_thread *thread); 641 struct mddev *mddev; 642 wait_queue_head_t wqueue; 643 unsigned long flags; 644 struct task_struct *tsk; 645 unsigned long timeout; 646 void *private; 647 }; 648 649 #define THREAD_WAKEUP 0 650 651 static inline void safe_put_page(struct page *p) 652 { 653 if (p) put_page(p); 654 } 655 656 extern int register_md_personality(struct md_personality *p); 657 extern int unregister_md_personality(struct md_personality *p); 658 extern int register_md_cluster_operations(struct md_cluster_operations *ops, 659 struct module *module); 660 extern int unregister_md_cluster_operations(void); 661 extern int md_setup_cluster(struct mddev *mddev, int nodes); 662 extern void md_cluster_stop(struct mddev *mddev); 663 extern struct md_thread *md_register_thread( 664 void (*run)(struct md_thread *thread), 665 struct mddev *mddev, 666 const char *name); 667 extern void md_unregister_thread(struct md_thread **threadp); 668 extern void md_wakeup_thread(struct md_thread *thread); 669 extern void md_check_recovery(struct mddev *mddev); 670 extern void md_reap_sync_thread(struct mddev *mddev); 671 extern int mddev_init_writes_pending(struct mddev *mddev); 672 extern bool md_write_start(struct mddev *mddev, struct bio *bi); 673 extern void md_write_inc(struct mddev *mddev, struct bio *bi); 674 extern void md_write_end(struct mddev *mddev); 675 extern void md_done_sync(struct mddev *mddev, int blocks, int ok); 676 extern void md_error(struct mddev *mddev, struct md_rdev *rdev); 677 extern void md_finish_reshape(struct mddev *mddev); 678 679 extern int mddev_congested(struct mddev *mddev, int bits); 680 extern void md_flush_request(struct mddev *mddev, struct bio *bio); 681 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev, 682 sector_t sector, int size, struct page *page); 683 extern int md_super_wait(struct mddev *mddev); 684 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, 685 struct page *page, int op, int op_flags, 686 bool metadata_op); 687 extern void md_do_sync(struct md_thread *thread); 688 extern void md_new_event(struct mddev *mddev); 689 extern void md_allow_write(struct mddev *mddev); 690 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); 691 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); 692 extern int md_check_no_bitmap(struct mddev *mddev); 693 extern int md_integrity_register(struct mddev *mddev); 694 extern int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev); 695 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale); 696 697 extern void mddev_init(struct mddev *mddev); 698 extern int md_run(struct mddev *mddev); 699 extern int md_start(struct mddev *mddev); 700 extern void md_stop(struct mddev *mddev); 701 extern void md_stop_writes(struct mddev *mddev); 702 extern int md_rdev_init(struct md_rdev *rdev); 703 extern void md_rdev_clear(struct md_rdev *rdev); 704 705 extern void md_handle_request(struct mddev *mddev, struct bio *bio); 706 extern void mddev_suspend(struct mddev *mddev); 707 extern void mddev_resume(struct mddev *mddev); 708 extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs, 709 struct mddev *mddev); 710 711 extern void md_reload_sb(struct mddev *mddev, int raid_disk); 712 extern void md_update_sb(struct mddev *mddev, int force); 713 extern void md_kick_rdev_from_array(struct md_rdev * rdev); 714 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr); 715 struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev); 716 717 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev) 718 { 719 int faulty = test_bit(Faulty, &rdev->flags); 720 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) { 721 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 722 md_wakeup_thread(mddev->thread); 723 } 724 } 725 726 extern struct md_cluster_operations *md_cluster_ops; 727 static inline int mddev_is_clustered(struct mddev *mddev) 728 { 729 return mddev->cluster_info && mddev->bitmap_info.nodes > 1; 730 } 731 732 /* clear unsupported mddev_flags */ 733 static inline void mddev_clear_unsupported_flags(struct mddev *mddev, 734 unsigned long unsupported_flags) 735 { 736 mddev->flags &= ~unsupported_flags; 737 } 738 739 static inline void mddev_check_writesame(struct mddev *mddev, struct bio *bio) 740 { 741 if (bio_op(bio) == REQ_OP_WRITE_SAME && 742 !bio->bi_disk->queue->limits.max_write_same_sectors) 743 mddev->queue->limits.max_write_same_sectors = 0; 744 } 745 746 static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio) 747 { 748 if (bio_op(bio) == REQ_OP_WRITE_ZEROES && 749 !bio->bi_disk->queue->limits.max_write_zeroes_sectors) 750 mddev->queue->limits.max_write_zeroes_sectors = 0; 751 } 752 #endif /* _MD_MD_H */ 753