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/kobject.h> 21 #include <linux/list.h> 22 #include <linux/mm.h> 23 #include <linux/mutex.h> 24 #include <linux/timer.h> 25 #include <linux/wait.h> 26 #include <linux/workqueue.h> 27 #include "md-cluster.h" 28 29 #define MaxSector (~(sector_t)0) 30 31 /* Bad block numbers are stored sorted in a single page. 32 * 64bits is used for each block or extent. 33 * 54 bits are sector number, 9 bits are extent size, 34 * 1 bit is an 'acknowledged' flag. 35 */ 36 #define MD_MAX_BADBLOCKS (PAGE_SIZE/8) 37 38 /* 39 * MD's 'extended' device 40 */ 41 struct md_rdev { 42 struct list_head same_set; /* RAID devices within the same set */ 43 44 sector_t sectors; /* Device size (in 512bytes sectors) */ 45 struct mddev *mddev; /* RAID array if running */ 46 int last_events; /* IO event timestamp */ 47 48 /* 49 * If meta_bdev is non-NULL, it means that a separate device is 50 * being used to store the metadata (superblock/bitmap) which 51 * would otherwise be contained on the same device as the data (bdev). 52 */ 53 struct block_device *meta_bdev; 54 struct block_device *bdev; /* block device handle */ 55 56 struct page *sb_page, *bb_page; 57 int sb_loaded; 58 __u64 sb_events; 59 sector_t data_offset; /* start of data in array */ 60 sector_t new_data_offset;/* only relevant while reshaping */ 61 sector_t sb_start; /* offset of the super block (in 512byte sectors) */ 62 int sb_size; /* bytes in the superblock */ 63 int preferred_minor; /* autorun support */ 64 65 struct kobject kobj; 66 67 /* A device can be in one of three states based on two flags: 68 * Not working: faulty==1 in_sync==0 69 * Fully working: faulty==0 in_sync==1 70 * Working, but not 71 * in sync with array 72 * faulty==0 in_sync==0 73 * 74 * It can never have faulty==1, in_sync==1 75 * This reduces the burden of testing multiple flags in many cases 76 */ 77 78 unsigned long flags; /* bit set of 'enum flag_bits' bits. */ 79 wait_queue_head_t blocked_wait; 80 81 int desc_nr; /* descriptor index in the superblock */ 82 int raid_disk; /* role of device in array */ 83 int new_raid_disk; /* role that the device will have in 84 * the array after a level-change completes. 85 */ 86 int saved_raid_disk; /* role that device used to have in the 87 * array and could again if we did a partial 88 * resync from the bitmap 89 */ 90 union { 91 sector_t recovery_offset;/* If this device has been partially 92 * recovered, this is where we were 93 * up to. 94 */ 95 sector_t journal_tail; /* If this device is a journal device, 96 * this is the journal tail (journal 97 * recovery start point) 98 */ 99 }; 100 101 atomic_t nr_pending; /* number of pending requests. 102 * only maintained for arrays that 103 * support hot removal 104 */ 105 atomic_t read_errors; /* number of consecutive read errors that 106 * we have tried to ignore. 107 */ 108 struct timespec last_read_error; /* monotonic time since our 109 * last read error 110 */ 111 atomic_t corrected_errors; /* number of corrected read errors, 112 * for reporting to userspace and storing 113 * in superblock. 114 */ 115 struct work_struct del_work; /* used for delayed sysfs removal */ 116 117 struct kernfs_node *sysfs_state; /* handle for 'state' 118 * sysfs entry */ 119 120 struct badblocks { 121 int count; /* count of bad blocks */ 122 int unacked_exist; /* there probably are unacknowledged 123 * bad blocks. This is only cleared 124 * when a read discovers none 125 */ 126 int shift; /* shift from sectors to block size 127 * a -ve shift means badblocks are 128 * disabled.*/ 129 u64 *page; /* badblock list */ 130 int changed; 131 seqlock_t lock; 132 133 sector_t sector; 134 sector_t size; /* in sectors */ 135 } badblocks; 136 }; 137 enum flag_bits { 138 Faulty, /* device is known to have a fault */ 139 In_sync, /* device is in_sync with rest of array */ 140 Bitmap_sync, /* ..actually, not quite In_sync. Need a 141 * bitmap-based recovery to get fully in sync 142 */ 143 WriteMostly, /* Avoid reading if at all possible */ 144 AutoDetected, /* added by auto-detect */ 145 Blocked, /* An error occurred but has not yet 146 * been acknowledged by the metadata 147 * handler, so don't allow writes 148 * until it is cleared */ 149 WriteErrorSeen, /* A write error has been seen on this 150 * device 151 */ 152 FaultRecorded, /* Intermediate state for clearing 153 * Blocked. The Fault is/will-be 154 * recorded in the metadata, but that 155 * metadata hasn't been stored safely 156 * on disk yet. 157 */ 158 BlockedBadBlocks, /* A writer is blocked because they 159 * found an unacknowledged bad-block. 160 * This can safely be cleared at any 161 * time, and the writer will re-check. 162 * It may be set at any time, and at 163 * worst the writer will timeout and 164 * re-check. So setting it as 165 * accurately as possible is good, but 166 * not absolutely critical. 167 */ 168 WantReplacement, /* This device is a candidate to be 169 * hot-replaced, either because it has 170 * reported some faults, or because 171 * of explicit request. 172 */ 173 Replacement, /* This device is a replacement for 174 * a want_replacement device with same 175 * raid_disk number. 176 */ 177 Candidate, /* For clustered environments only: 178 * This device is seen locally but not 179 * by the whole cluster 180 */ 181 Journal, /* This device is used as journal for 182 * raid-5/6. 183 * Usually, this device should be faster 184 * than other devices in the array 185 */ 186 }; 187 188 #define BB_LEN_MASK (0x00000000000001FFULL) 189 #define BB_OFFSET_MASK (0x7FFFFFFFFFFFFE00ULL) 190 #define BB_ACK_MASK (0x8000000000000000ULL) 191 #define BB_MAX_LEN 512 192 #define BB_OFFSET(x) (((x) & BB_OFFSET_MASK) >> 9) 193 #define BB_LEN(x) (((x) & BB_LEN_MASK) + 1) 194 #define BB_ACK(x) (!!((x) & BB_ACK_MASK)) 195 #define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63)) 196 197 extern int md_is_badblock(struct badblocks *bb, sector_t s, int sectors, 198 sector_t *first_bad, int *bad_sectors); 199 static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors, 200 sector_t *first_bad, int *bad_sectors) 201 { 202 if (unlikely(rdev->badblocks.count)) { 203 int rv = md_is_badblock(&rdev->badblocks, rdev->data_offset + s, 204 sectors, 205 first_bad, bad_sectors); 206 if (rv) 207 *first_bad -= rdev->data_offset; 208 return rv; 209 } 210 return 0; 211 } 212 extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 213 int is_new); 214 extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 215 int is_new); 216 extern void md_ack_all_badblocks(struct badblocks *bb); 217 218 struct md_cluster_info; 219 220 struct mddev { 221 void *private; 222 struct md_personality *pers; 223 dev_t unit; 224 int md_minor; 225 struct list_head disks; 226 unsigned long flags; 227 #define MD_CHANGE_DEVS 0 /* Some device status has changed */ 228 #define MD_CHANGE_CLEAN 1 /* transition to or from 'clean' */ 229 #define MD_CHANGE_PENDING 2 /* switch from 'clean' to 'active' in progress */ 230 #define MD_UPDATE_SB_FLAGS (1 | 2 | 4) /* If these are set, md_update_sb needed */ 231 #define MD_ARRAY_FIRST_USE 3 /* First use of array, needs initialization */ 232 #define MD_STILL_CLOSED 4 /* If set, then array has not been opened since 233 * md_ioctl checked on it. 234 */ 235 #define MD_JOURNAL_CLEAN 5 /* A raid with journal is already clean */ 236 #define MD_HAS_JOURNAL 6 /* The raid array has journal feature set */ 237 238 int suspended; 239 atomic_t active_io; 240 int ro; 241 int sysfs_active; /* set when sysfs deletes 242 * are happening, so run/ 243 * takeover/stop are not safe 244 */ 245 int ready; /* See when safe to pass 246 * IO requests down */ 247 struct gendisk *gendisk; 248 249 struct kobject kobj; 250 int hold_active; 251 #define UNTIL_IOCTL 1 252 #define UNTIL_STOP 2 253 254 /* Superblock information */ 255 int major_version, 256 minor_version, 257 patch_version; 258 int persistent; 259 int external; /* metadata is 260 * managed externally */ 261 char metadata_type[17]; /* externally set*/ 262 int chunk_sectors; 263 time_t ctime, utime; 264 int level, layout; 265 char clevel[16]; 266 int raid_disks; 267 int max_disks; 268 sector_t dev_sectors; /* used size of 269 * component devices */ 270 sector_t array_sectors; /* exported array size */ 271 int external_size; /* size managed 272 * externally */ 273 __u64 events; 274 /* If the last 'event' was simply a clean->dirty transition, and 275 * we didn't write it to the spares, then it is safe and simple 276 * to just decrement the event count on a dirty->clean transition. 277 * So we record that possibility here. 278 */ 279 int can_decrease_events; 280 281 char uuid[16]; 282 283 /* If the array is being reshaped, we need to record the 284 * new shape and an indication of where we are up to. 285 * This is written to the superblock. 286 * If reshape_position is MaxSector, then no reshape is happening (yet). 287 */ 288 sector_t reshape_position; 289 int delta_disks, new_level, new_layout; 290 int new_chunk_sectors; 291 int reshape_backwards; 292 293 struct md_thread *thread; /* management thread */ 294 struct md_thread *sync_thread; /* doing resync or reconstruct */ 295 296 /* 'last_sync_action' is initialized to "none". It is set when a 297 * sync operation (i.e "data-check", "requested-resync", "resync", 298 * "recovery", or "reshape") is started. It holds this value even 299 * when the sync thread is "frozen" (interrupted) or "idle" (stopped 300 * or finished). It is overwritten when a new sync operation is begun. 301 */ 302 char *last_sync_action; 303 sector_t curr_resync; /* last block scheduled */ 304 /* As resync requests can complete out of order, we cannot easily track 305 * how much resync has been completed. So we occasionally pause until 306 * everything completes, then set curr_resync_completed to curr_resync. 307 * As such it may be well behind the real resync mark, but it is a value 308 * we are certain of. 309 */ 310 sector_t curr_resync_completed; 311 unsigned long resync_mark; /* a recent timestamp */ 312 sector_t resync_mark_cnt;/* blocks written at resync_mark */ 313 sector_t curr_mark_cnt; /* blocks scheduled now */ 314 315 sector_t resync_max_sectors; /* may be set by personality */ 316 317 atomic64_t resync_mismatches; /* count of sectors where 318 * parity/replica mismatch found 319 */ 320 321 /* allow user-space to request suspension of IO to regions of the array */ 322 sector_t suspend_lo; 323 sector_t suspend_hi; 324 /* if zero, use the system-wide default */ 325 int sync_speed_min; 326 int sync_speed_max; 327 328 /* resync even though the same disks are shared among md-devices */ 329 int parallel_resync; 330 331 int ok_start_degraded; 332 /* recovery/resync flags 333 * NEEDED: we might need to start a resync/recover 334 * RUNNING: a thread is running, or about to be started 335 * SYNC: actually doing a resync, not a recovery 336 * RECOVER: doing recovery, or need to try it. 337 * INTR: resync needs to be aborted for some reason 338 * DONE: thread is done and is waiting to be reaped 339 * REQUEST: user-space has requested a sync (used with SYNC) 340 * CHECK: user-space request for check-only, no repair 341 * RESHAPE: A reshape is happening 342 * ERROR: sync-action interrupted because io-error 343 * 344 * If neither SYNC or RESHAPE are set, then it is a recovery. 345 */ 346 #define MD_RECOVERY_RUNNING 0 347 #define MD_RECOVERY_SYNC 1 348 #define MD_RECOVERY_RECOVER 2 349 #define MD_RECOVERY_INTR 3 350 #define MD_RECOVERY_DONE 4 351 #define MD_RECOVERY_NEEDED 5 352 #define MD_RECOVERY_REQUESTED 6 353 #define MD_RECOVERY_CHECK 7 354 #define MD_RECOVERY_RESHAPE 8 355 #define MD_RECOVERY_FROZEN 9 356 #define MD_RECOVERY_ERROR 10 357 358 unsigned long recovery; 359 /* If a RAID personality determines that recovery (of a particular 360 * device) will fail due to a read error on the source device, it 361 * takes a copy of this number and does not attempt recovery again 362 * until this number changes. 363 */ 364 int recovery_disabled; 365 366 int in_sync; /* know to not need resync */ 367 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so 368 * that we are never stopping an array while it is open. 369 * 'reconfig_mutex' protects all other reconfiguration. 370 * These locks are separate due to conflicting interactions 371 * with bdev->bd_mutex. 372 * Lock ordering is: 373 * reconfig_mutex -> bd_mutex : e.g. do_md_run -> revalidate_disk 374 * bd_mutex -> open_mutex: e.g. __blkdev_get -> md_open 375 */ 376 struct mutex open_mutex; 377 struct mutex reconfig_mutex; 378 atomic_t active; /* general refcount */ 379 atomic_t openers; /* number of active opens */ 380 381 int changed; /* True if we might need to 382 * reread partition info */ 383 int degraded; /* whether md should consider 384 * adding a spare 385 */ 386 387 atomic_t recovery_active; /* blocks scheduled, but not written */ 388 wait_queue_head_t recovery_wait; 389 sector_t recovery_cp; 390 sector_t resync_min; /* user requested sync 391 * starts here */ 392 sector_t resync_max; /* resync should pause 393 * when it gets here */ 394 395 struct kernfs_node *sysfs_state; /* handle for 'array_state' 396 * file in sysfs. 397 */ 398 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */ 399 400 struct work_struct del_work; /* used for delayed sysfs removal */ 401 402 /* "lock" protects: 403 * flush_bio transition from NULL to !NULL 404 * rdev superblocks, events 405 * clearing MD_CHANGE_* 406 * in_sync - and related safemode and MD_CHANGE changes 407 * pers (also protected by reconfig_mutex and pending IO). 408 * clearing ->bitmap 409 * clearing ->bitmap_info.file 410 * changing ->resync_{min,max} 411 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max}) 412 */ 413 spinlock_t lock; 414 wait_queue_head_t sb_wait; /* for waiting on superblock updates */ 415 atomic_t pending_writes; /* number of active superblock writes */ 416 417 unsigned int safemode; /* if set, update "clean" superblock 418 * when no writes pending. 419 */ 420 unsigned int safemode_delay; 421 struct timer_list safemode_timer; 422 atomic_t 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; 456 457 /* Generic flush handling. 458 * The last to finish preflush schedules a worker to submit 459 * the rest of the request (without the REQ_FLUSH flag). 460 */ 461 struct bio *flush_bio; 462 atomic_t flush_pending; 463 struct work_struct flush_work; 464 struct work_struct event_work; /* used by dm to report failure event */ 465 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev); 466 struct md_cluster_info *cluster_info; 467 }; 468 469 static inline int __must_check mddev_lock(struct mddev *mddev) 470 { 471 return mutex_lock_interruptible(&mddev->reconfig_mutex); 472 } 473 474 /* Sometimes we need to take the lock in a situation where 475 * failure due to interrupts is not acceptable. 476 */ 477 static inline void mddev_lock_nointr(struct mddev *mddev) 478 { 479 mutex_lock(&mddev->reconfig_mutex); 480 } 481 482 static inline int mddev_is_locked(struct mddev *mddev) 483 { 484 return mutex_is_locked(&mddev->reconfig_mutex); 485 } 486 487 static inline int mddev_trylock(struct mddev *mddev) 488 { 489 return mutex_trylock(&mddev->reconfig_mutex); 490 } 491 extern void mddev_unlock(struct mddev *mddev); 492 493 static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors) 494 { 495 atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io); 496 } 497 498 struct md_personality 499 { 500 char *name; 501 int level; 502 struct list_head list; 503 struct module *owner; 504 void (*make_request)(struct mddev *mddev, struct bio *bio); 505 int (*run)(struct mddev *mddev); 506 void (*free)(struct mddev *mddev, void *priv); 507 void (*status)(struct seq_file *seq, struct mddev *mddev); 508 /* error_handler must set ->faulty and clear ->in_sync 509 * if appropriate, and should abort recovery if needed 510 */ 511 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev); 512 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev); 513 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev); 514 int (*spare_active) (struct mddev *mddev); 515 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped); 516 int (*resize) (struct mddev *mddev, sector_t sectors); 517 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks); 518 int (*check_reshape) (struct mddev *mddev); 519 int (*start_reshape) (struct mddev *mddev); 520 void (*finish_reshape) (struct mddev *mddev); 521 /* quiesce moves between quiescence states 522 * 0 - fully active 523 * 1 - no new requests allowed 524 * others - reserved 525 */ 526 void (*quiesce) (struct mddev *mddev, int state); 527 /* takeover is used to transition an array from one 528 * personality to another. The new personality must be able 529 * to handle the data in the current layout. 530 * e.g. 2drive raid1 -> 2drive raid5 531 * ndrive raid5 -> degraded n+1drive raid6 with special layout 532 * If the takeover succeeds, a new 'private' structure is returned. 533 * This needs to be installed and then ->run used to activate the 534 * array. 535 */ 536 void *(*takeover) (struct mddev *mddev); 537 /* congested implements bdi.congested_fn(). 538 * Will not be called while array is 'suspended' */ 539 int (*congested)(struct mddev *mddev, int bits); 540 }; 541 542 struct md_sysfs_entry { 543 struct attribute attr; 544 ssize_t (*show)(struct mddev *, char *); 545 ssize_t (*store)(struct mddev *, const char *, size_t); 546 }; 547 extern struct attribute_group md_bitmap_group; 548 549 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name) 550 { 551 if (sd) 552 return sysfs_get_dirent(sd, name); 553 return sd; 554 } 555 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd) 556 { 557 if (sd) 558 sysfs_notify_dirent(sd); 559 } 560 561 static inline char * mdname (struct mddev * mddev) 562 { 563 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; 564 } 565 566 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev) 567 { 568 char nm[20]; 569 if (!test_bit(Replacement, &rdev->flags) && mddev->kobj.sd) { 570 sprintf(nm, "rd%d", rdev->raid_disk); 571 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); 572 } else 573 return 0; 574 } 575 576 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev) 577 { 578 char nm[20]; 579 if (!test_bit(Replacement, &rdev->flags) && mddev->kobj.sd) { 580 sprintf(nm, "rd%d", rdev->raid_disk); 581 sysfs_remove_link(&mddev->kobj, nm); 582 } 583 } 584 585 /* 586 * iterates through some rdev ringlist. It's safe to remove the 587 * current 'rdev'. Dont touch 'tmp' though. 588 */ 589 #define rdev_for_each_list(rdev, tmp, head) \ 590 list_for_each_entry_safe(rdev, tmp, head, same_set) 591 592 /* 593 * iterates through the 'same array disks' ringlist 594 */ 595 #define rdev_for_each(rdev, mddev) \ 596 list_for_each_entry(rdev, &((mddev)->disks), same_set) 597 598 #define rdev_for_each_safe(rdev, tmp, mddev) \ 599 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) 600 601 #define rdev_for_each_rcu(rdev, mddev) \ 602 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) 603 604 struct md_thread { 605 void (*run) (struct md_thread *thread); 606 struct mddev *mddev; 607 wait_queue_head_t wqueue; 608 unsigned long flags; 609 struct task_struct *tsk; 610 unsigned long timeout; 611 void *private; 612 }; 613 614 #define THREAD_WAKEUP 0 615 616 static inline void safe_put_page(struct page *p) 617 { 618 if (p) put_page(p); 619 } 620 621 extern int register_md_personality(struct md_personality *p); 622 extern int unregister_md_personality(struct md_personality *p); 623 extern int register_md_cluster_operations(struct md_cluster_operations *ops, 624 struct module *module); 625 extern int unregister_md_cluster_operations(void); 626 extern int md_setup_cluster(struct mddev *mddev, int nodes); 627 extern void md_cluster_stop(struct mddev *mddev); 628 extern struct md_thread *md_register_thread( 629 void (*run)(struct md_thread *thread), 630 struct mddev *mddev, 631 const char *name); 632 extern void md_unregister_thread(struct md_thread **threadp); 633 extern void md_wakeup_thread(struct md_thread *thread); 634 extern void md_check_recovery(struct mddev *mddev); 635 extern void md_reap_sync_thread(struct mddev *mddev); 636 extern void md_write_start(struct mddev *mddev, struct bio *bi); 637 extern void md_write_end(struct mddev *mddev); 638 extern void md_done_sync(struct mddev *mddev, int blocks, int ok); 639 extern void md_error(struct mddev *mddev, struct md_rdev *rdev); 640 extern void md_finish_reshape(struct mddev *mddev); 641 642 extern int mddev_congested(struct mddev *mddev, int bits); 643 extern void md_flush_request(struct mddev *mddev, struct bio *bio); 644 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev, 645 sector_t sector, int size, struct page *page); 646 extern void md_super_wait(struct mddev *mddev); 647 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, 648 struct page *page, int rw, bool metadata_op); 649 extern void md_do_sync(struct md_thread *thread); 650 extern void md_new_event(struct mddev *mddev); 651 extern int md_allow_write(struct mddev *mddev); 652 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); 653 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); 654 extern int md_check_no_bitmap(struct mddev *mddev); 655 extern int md_integrity_register(struct mddev *mddev); 656 extern void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev); 657 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale); 658 659 extern void mddev_init(struct mddev *mddev); 660 extern int md_run(struct mddev *mddev); 661 extern void md_stop(struct mddev *mddev); 662 extern void md_stop_writes(struct mddev *mddev); 663 extern int md_rdev_init(struct md_rdev *rdev); 664 extern void md_rdev_clear(struct md_rdev *rdev); 665 666 extern void mddev_suspend(struct mddev *mddev); 667 extern void mddev_resume(struct mddev *mddev); 668 extern struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask, 669 struct mddev *mddev); 670 extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs, 671 struct mddev *mddev); 672 673 extern void md_unplug(struct blk_plug_cb *cb, bool from_schedule); 674 extern void md_reload_sb(struct mddev *mddev, int raid_disk); 675 extern void md_update_sb(struct mddev *mddev, int force); 676 extern void md_kick_rdev_from_array(struct md_rdev * rdev); 677 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr); 678 static inline int mddev_check_plugged(struct mddev *mddev) 679 { 680 return !!blk_check_plugged(md_unplug, mddev, 681 sizeof(struct blk_plug_cb)); 682 } 683 684 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev) 685 { 686 int faulty = test_bit(Faulty, &rdev->flags); 687 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) { 688 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 689 md_wakeup_thread(mddev->thread); 690 } 691 } 692 693 extern struct md_cluster_operations *md_cluster_ops; 694 static inline int mddev_is_clustered(struct mddev *mddev) 695 { 696 return mddev->cluster_info && mddev->bitmap_info.nodes > 1; 697 } 698 #endif /* _MD_MD_H */ 699