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/kobject.h> 20 #include <linux/list.h> 21 #include <linux/mm.h> 22 #include <linux/mutex.h> 23 #include <linux/timer.h> 24 #include <linux/wait.h> 25 #include <linux/workqueue.h> 26 #include "md-cluster.h" 27 28 #define MaxSector (~(sector_t)0) 29 30 /* Bad block numbers are stored sorted in a single page. 31 * 64bits is used for each block or extent. 32 * 54 bits are sector number, 9 bits are extent size, 33 * 1 bit is an 'acknowledged' flag. 34 */ 35 #define MD_MAX_BADBLOCKS (PAGE_SIZE/8) 36 37 /* 38 * MD's 'extended' device 39 */ 40 struct md_rdev { 41 struct list_head same_set; /* RAID devices within the same set */ 42 43 sector_t sectors; /* Device size (in 512bytes sectors) */ 44 struct mddev *mddev; /* RAID array if running */ 45 int last_events; /* IO event timestamp */ 46 47 /* 48 * If meta_bdev is non-NULL, it means that a separate device is 49 * being used to store the metadata (superblock/bitmap) which 50 * would otherwise be contained on the same device as the data (bdev). 51 */ 52 struct block_device *meta_bdev; 53 struct block_device *bdev; /* block device handle */ 54 55 struct page *sb_page, *bb_page; 56 int sb_loaded; 57 __u64 sb_events; 58 sector_t data_offset; /* start of data in array */ 59 sector_t new_data_offset;/* only relevant while reshaping */ 60 sector_t sb_start; /* offset of the super block (in 512byte sectors) */ 61 int sb_size; /* bytes in the superblock */ 62 int preferred_minor; /* autorun support */ 63 64 struct kobject kobj; 65 66 /* A device can be in one of three states based on two flags: 67 * Not working: faulty==1 in_sync==0 68 * Fully working: faulty==0 in_sync==1 69 * Working, but not 70 * in sync with array 71 * faulty==0 in_sync==0 72 * 73 * It can never have faulty==1, in_sync==1 74 * This reduces the burden of testing multiple flags in many cases 75 */ 76 77 unsigned long flags; /* bit set of 'enum flag_bits' bits. */ 78 wait_queue_head_t blocked_wait; 79 80 int desc_nr; /* descriptor index in the superblock */ 81 int raid_disk; /* role of device in array */ 82 int new_raid_disk; /* role that the device will have in 83 * the array after a level-change completes. 84 */ 85 int saved_raid_disk; /* role that device used to have in the 86 * array and could again if we did a partial 87 * resync from the bitmap 88 */ 89 sector_t recovery_offset;/* If this device has been partially 90 * recovered, this is where we were 91 * up to. 92 */ 93 94 atomic_t nr_pending; /* number of pending requests. 95 * only maintained for arrays that 96 * support hot removal 97 */ 98 atomic_t read_errors; /* number of consecutive read errors that 99 * we have tried to ignore. 100 */ 101 struct timespec last_read_error; /* monotonic time since our 102 * last read error 103 */ 104 atomic_t corrected_errors; /* number of corrected read errors, 105 * for reporting to userspace and storing 106 * in superblock. 107 */ 108 struct work_struct del_work; /* used for delayed sysfs removal */ 109 110 struct kernfs_node *sysfs_state; /* handle for 'state' 111 * sysfs entry */ 112 113 struct badblocks { 114 int count; /* count of bad blocks */ 115 int unacked_exist; /* there probably are unacknowledged 116 * bad blocks. This is only cleared 117 * when a read discovers none 118 */ 119 int shift; /* shift from sectors to block size 120 * a -ve shift means badblocks are 121 * disabled.*/ 122 u64 *page; /* badblock list */ 123 int changed; 124 seqlock_t lock; 125 126 sector_t sector; 127 sector_t size; /* in sectors */ 128 } badblocks; 129 }; 130 enum flag_bits { 131 Faulty, /* device is known to have a fault */ 132 In_sync, /* device is in_sync with rest of array */ 133 Bitmap_sync, /* ..actually, not quite In_sync. Need a 134 * bitmap-based recovery to get fully in sync 135 */ 136 Unmerged, /* device is being added to array and should 137 * be considerred for bvec_merge_fn but not 138 * yet for actual IO 139 */ 140 WriteMostly, /* Avoid reading if at all possible */ 141 AutoDetected, /* added by auto-detect */ 142 Blocked, /* An error occurred but has not yet 143 * been acknowledged by the metadata 144 * handler, so don't allow writes 145 * until it is cleared */ 146 WriteErrorSeen, /* A write error has been seen on this 147 * device 148 */ 149 FaultRecorded, /* Intermediate state for clearing 150 * Blocked. The Fault is/will-be 151 * recorded in the metadata, but that 152 * metadata hasn't been stored safely 153 * on disk yet. 154 */ 155 BlockedBadBlocks, /* A writer is blocked because they 156 * found an unacknowledged bad-block. 157 * This can safely be cleared at any 158 * time, and the writer will re-check. 159 * It may be set at any time, and at 160 * worst the writer will timeout and 161 * re-check. So setting it as 162 * accurately as possible is good, but 163 * not absolutely critical. 164 */ 165 WantReplacement, /* This device is a candidate to be 166 * hot-replaced, either because it has 167 * reported some faults, or because 168 * of explicit request. 169 */ 170 Replacement, /* This device is a replacement for 171 * a want_replacement device with same 172 * raid_disk number. 173 */ 174 Candidate, /* For clustered environments only: 175 * This device is seen locally but not 176 * by the whole cluster 177 */ 178 }; 179 180 #define BB_LEN_MASK (0x00000000000001FFULL) 181 #define BB_OFFSET_MASK (0x7FFFFFFFFFFFFE00ULL) 182 #define BB_ACK_MASK (0x8000000000000000ULL) 183 #define BB_MAX_LEN 512 184 #define BB_OFFSET(x) (((x) & BB_OFFSET_MASK) >> 9) 185 #define BB_LEN(x) (((x) & BB_LEN_MASK) + 1) 186 #define BB_ACK(x) (!!((x) & BB_ACK_MASK)) 187 #define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63)) 188 189 extern int md_is_badblock(struct badblocks *bb, sector_t s, int sectors, 190 sector_t *first_bad, int *bad_sectors); 191 static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors, 192 sector_t *first_bad, int *bad_sectors) 193 { 194 if (unlikely(rdev->badblocks.count)) { 195 int rv = md_is_badblock(&rdev->badblocks, rdev->data_offset + s, 196 sectors, 197 first_bad, bad_sectors); 198 if (rv) 199 *first_bad -= rdev->data_offset; 200 return rv; 201 } 202 return 0; 203 } 204 extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 205 int is_new); 206 extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 207 int is_new); 208 extern void md_ack_all_badblocks(struct badblocks *bb); 209 210 struct md_cluster_info; 211 212 struct mddev { 213 void *private; 214 struct md_personality *pers; 215 dev_t unit; 216 int md_minor; 217 struct list_head disks; 218 unsigned long flags; 219 #define MD_CHANGE_DEVS 0 /* Some device status has changed */ 220 #define MD_CHANGE_CLEAN 1 /* transition to or from 'clean' */ 221 #define MD_CHANGE_PENDING 2 /* switch from 'clean' to 'active' in progress */ 222 #define MD_UPDATE_SB_FLAGS (1 | 2 | 4) /* If these are set, md_update_sb needed */ 223 #define MD_ARRAY_FIRST_USE 3 /* First use of array, needs initialization */ 224 #define MD_STILL_CLOSED 4 /* If set, then array has not been opened since 225 * md_ioctl checked on it. 226 */ 227 228 int suspended; 229 atomic_t active_io; 230 int ro; 231 int sysfs_active; /* set when sysfs deletes 232 * are happening, so run/ 233 * takeover/stop are not safe 234 */ 235 int ready; /* See when safe to pass 236 * IO requests down */ 237 struct gendisk *gendisk; 238 239 struct kobject kobj; 240 int hold_active; 241 #define UNTIL_IOCTL 1 242 #define UNTIL_STOP 2 243 244 /* Superblock information */ 245 int major_version, 246 minor_version, 247 patch_version; 248 int persistent; 249 int external; /* metadata is 250 * managed externally */ 251 char metadata_type[17]; /* externally set*/ 252 int chunk_sectors; 253 time_t ctime, utime; 254 int level, layout; 255 char clevel[16]; 256 int raid_disks; 257 int max_disks; 258 sector_t dev_sectors; /* used size of 259 * component devices */ 260 sector_t array_sectors; /* exported array size */ 261 int external_size; /* size managed 262 * externally */ 263 __u64 events; 264 /* If the last 'event' was simply a clean->dirty transition, and 265 * we didn't write it to the spares, then it is safe and simple 266 * to just decrement the event count on a dirty->clean transition. 267 * So we record that possibility here. 268 */ 269 int can_decrease_events; 270 271 char uuid[16]; 272 273 /* If the array is being reshaped, we need to record the 274 * new shape and an indication of where we are up to. 275 * This is written to the superblock. 276 * If reshape_position is MaxSector, then no reshape is happening (yet). 277 */ 278 sector_t reshape_position; 279 int delta_disks, new_level, new_layout; 280 int new_chunk_sectors; 281 int reshape_backwards; 282 283 struct md_thread *thread; /* management thread */ 284 struct md_thread *sync_thread; /* doing resync or reconstruct */ 285 286 /* 'last_sync_action' is initialized to "none". It is set when a 287 * sync operation (i.e "data-check", "requested-resync", "resync", 288 * "recovery", or "reshape") is started. It holds this value even 289 * when the sync thread is "frozen" (interrupted) or "idle" (stopped 290 * or finished). It is overwritten when a new sync operation is begun. 291 */ 292 char *last_sync_action; 293 sector_t curr_resync; /* last block scheduled */ 294 /* As resync requests can complete out of order, we cannot easily track 295 * how much resync has been completed. So we occasionally pause until 296 * everything completes, then set curr_resync_completed to curr_resync. 297 * As such it may be well behind the real resync mark, but it is a value 298 * we are certain of. 299 */ 300 sector_t curr_resync_completed; 301 unsigned long resync_mark; /* a recent timestamp */ 302 sector_t resync_mark_cnt;/* blocks written at resync_mark */ 303 sector_t curr_mark_cnt; /* blocks scheduled now */ 304 305 sector_t resync_max_sectors; /* may be set by personality */ 306 307 atomic64_t resync_mismatches; /* count of sectors where 308 * parity/replica mismatch found 309 */ 310 311 /* allow user-space to request suspension of IO to regions of the array */ 312 sector_t suspend_lo; 313 sector_t suspend_hi; 314 /* if zero, use the system-wide default */ 315 int sync_speed_min; 316 int sync_speed_max; 317 318 /* resync even though the same disks are shared among md-devices */ 319 int parallel_resync; 320 321 int ok_start_degraded; 322 /* recovery/resync flags 323 * NEEDED: we might need to start a resync/recover 324 * RUNNING: a thread is running, or about to be started 325 * SYNC: actually doing a resync, not a recovery 326 * RECOVER: doing recovery, or need to try it. 327 * INTR: resync needs to be aborted for some reason 328 * DONE: thread is done and is waiting to be reaped 329 * REQUEST: user-space has requested a sync (used with SYNC) 330 * CHECK: user-space request for check-only, no repair 331 * RESHAPE: A reshape is happening 332 * ERROR: sync-action interrupted because io-error 333 * 334 * If neither SYNC or RESHAPE are set, then it is a recovery. 335 */ 336 #define MD_RECOVERY_RUNNING 0 337 #define MD_RECOVERY_SYNC 1 338 #define MD_RECOVERY_RECOVER 2 339 #define MD_RECOVERY_INTR 3 340 #define MD_RECOVERY_DONE 4 341 #define MD_RECOVERY_NEEDED 5 342 #define MD_RECOVERY_REQUESTED 6 343 #define MD_RECOVERY_CHECK 7 344 #define MD_RECOVERY_RESHAPE 8 345 #define MD_RECOVERY_FROZEN 9 346 #define MD_RECOVERY_ERROR 10 347 348 unsigned long recovery; 349 /* If a RAID personality determines that recovery (of a particular 350 * device) will fail due to a read error on the source device, it 351 * takes a copy of this number and does not attempt recovery again 352 * until this number changes. 353 */ 354 int recovery_disabled; 355 356 int in_sync; /* know to not need resync */ 357 /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so 358 * that we are never stopping an array while it is open. 359 * 'reconfig_mutex' protects all other reconfiguration. 360 * These locks are separate due to conflicting interactions 361 * with bdev->bd_mutex. 362 * Lock ordering is: 363 * reconfig_mutex -> bd_mutex : e.g. do_md_run -> revalidate_disk 364 * bd_mutex -> open_mutex: e.g. __blkdev_get -> md_open 365 */ 366 struct mutex open_mutex; 367 struct mutex reconfig_mutex; 368 atomic_t active; /* general refcount */ 369 atomic_t openers; /* number of active opens */ 370 371 int changed; /* True if we might need to 372 * reread partition info */ 373 int degraded; /* whether md should consider 374 * adding a spare 375 */ 376 int merge_check_needed; /* at least one 377 * member device 378 * has a 379 * merge_bvec_fn */ 380 381 atomic_t recovery_active; /* blocks scheduled, but not written */ 382 wait_queue_head_t recovery_wait; 383 sector_t recovery_cp; 384 sector_t resync_min; /* user requested sync 385 * starts here */ 386 sector_t resync_max; /* resync should pause 387 * when it gets here */ 388 389 struct kernfs_node *sysfs_state; /* handle for 'array_state' 390 * file in sysfs. 391 */ 392 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */ 393 394 struct work_struct del_work; /* used for delayed sysfs removal */ 395 396 /* "lock" protects: 397 * flush_bio transition from NULL to !NULL 398 * rdev superblocks, events 399 * clearing MD_CHANGE_* 400 * in_sync - and related safemode and MD_CHANGE changes 401 * pers (also protected by reconfig_mutex and pending IO). 402 * clearing ->bitmap 403 * clearing ->bitmap_info.file 404 * changing ->resync_{min,max} 405 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max}) 406 */ 407 spinlock_t lock; 408 wait_queue_head_t sb_wait; /* for waiting on superblock updates */ 409 atomic_t pending_writes; /* number of active superblock writes */ 410 411 unsigned int safemode; /* if set, update "clean" superblock 412 * when no writes pending. 413 */ 414 unsigned int safemode_delay; 415 struct timer_list safemode_timer; 416 atomic_t writes_pending; 417 struct request_queue *queue; /* for plugging ... */ 418 419 struct bitmap *bitmap; /* the bitmap for the device */ 420 struct { 421 struct file *file; /* the bitmap file */ 422 loff_t offset; /* offset from superblock of 423 * start of bitmap. May be 424 * negative, but not '0' 425 * For external metadata, offset 426 * from start of device. 427 */ 428 unsigned long space; /* space available at this offset */ 429 loff_t default_offset; /* this is the offset to use when 430 * hot-adding a bitmap. It should 431 * eventually be settable by sysfs. 432 */ 433 unsigned long default_space; /* space available at 434 * default offset */ 435 struct mutex mutex; 436 unsigned long chunksize; 437 unsigned long daemon_sleep; /* how many jiffies between updates? */ 438 unsigned long max_write_behind; /* write-behind mode */ 439 int external; 440 int nodes; /* Maximum number of nodes in the cluster */ 441 char cluster_name[64]; /* Name of the cluster */ 442 } bitmap_info; 443 444 atomic_t max_corr_read_errors; /* max read retries */ 445 struct list_head all_mddevs; 446 447 struct attribute_group *to_remove; 448 449 struct bio_set *bio_set; 450 451 /* Generic flush handling. 452 * The last to finish preflush schedules a worker to submit 453 * the rest of the request (without the REQ_FLUSH flag). 454 */ 455 struct bio *flush_bio; 456 atomic_t flush_pending; 457 struct work_struct flush_work; 458 struct work_struct event_work; /* used by dm to report failure event */ 459 void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev); 460 struct md_cluster_info *cluster_info; 461 }; 462 463 static inline int __must_check mddev_lock(struct mddev *mddev) 464 { 465 return mutex_lock_interruptible(&mddev->reconfig_mutex); 466 } 467 468 /* Sometimes we need to take the lock in a situation where 469 * failure due to interrupts is not acceptable. 470 */ 471 static inline void mddev_lock_nointr(struct mddev *mddev) 472 { 473 mutex_lock(&mddev->reconfig_mutex); 474 } 475 476 static inline int mddev_is_locked(struct mddev *mddev) 477 { 478 return mutex_is_locked(&mddev->reconfig_mutex); 479 } 480 481 static inline int mddev_trylock(struct mddev *mddev) 482 { 483 return mutex_trylock(&mddev->reconfig_mutex); 484 } 485 extern void mddev_unlock(struct mddev *mddev); 486 487 static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors) 488 { 489 atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io); 490 } 491 492 struct md_personality 493 { 494 char *name; 495 int level; 496 struct list_head list; 497 struct module *owner; 498 void (*make_request)(struct mddev *mddev, struct bio *bio); 499 int (*run)(struct mddev *mddev); 500 void (*free)(struct mddev *mddev, void *priv); 501 void (*status)(struct seq_file *seq, struct mddev *mddev); 502 /* error_handler must set ->faulty and clear ->in_sync 503 * if appropriate, and should abort recovery if needed 504 */ 505 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev); 506 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev); 507 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev); 508 int (*spare_active) (struct mddev *mddev); 509 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped); 510 int (*resize) (struct mddev *mddev, sector_t sectors); 511 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks); 512 int (*check_reshape) (struct mddev *mddev); 513 int (*start_reshape) (struct mddev *mddev); 514 void (*finish_reshape) (struct mddev *mddev); 515 /* quiesce moves between quiescence states 516 * 0 - fully active 517 * 1 - no new requests allowed 518 * others - reserved 519 */ 520 void (*quiesce) (struct mddev *mddev, int state); 521 /* takeover is used to transition an array from one 522 * personality to another. The new personality must be able 523 * to handle the data in the current layout. 524 * e.g. 2drive raid1 -> 2drive raid5 525 * ndrive raid5 -> degraded n+1drive raid6 with special layout 526 * If the takeover succeeds, a new 'private' structure is returned. 527 * This needs to be installed and then ->run used to activate the 528 * array. 529 */ 530 void *(*takeover) (struct mddev *mddev); 531 /* congested implements bdi.congested_fn(). 532 * Will not be called while array is 'suspended' */ 533 int (*congested)(struct mddev *mddev, int bits); 534 /* mergeable_bvec is use to implement ->merge_bvec_fn */ 535 int (*mergeable_bvec)(struct mddev *mddev, 536 struct bvec_merge_data *bvm, 537 struct bio_vec *biovec); 538 }; 539 540 struct md_sysfs_entry { 541 struct attribute attr; 542 ssize_t (*show)(struct mddev *, char *); 543 ssize_t (*store)(struct mddev *, const char *, size_t); 544 }; 545 extern struct attribute_group md_bitmap_group; 546 547 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name) 548 { 549 if (sd) 550 return sysfs_get_dirent(sd, name); 551 return sd; 552 } 553 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd) 554 { 555 if (sd) 556 sysfs_notify_dirent(sd); 557 } 558 559 static inline char * mdname (struct mddev * mddev) 560 { 561 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; 562 } 563 564 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev) 565 { 566 char nm[20]; 567 if (!test_bit(Replacement, &rdev->flags) && mddev->kobj.sd) { 568 sprintf(nm, "rd%d", rdev->raid_disk); 569 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); 570 } else 571 return 0; 572 } 573 574 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev) 575 { 576 char nm[20]; 577 if (!test_bit(Replacement, &rdev->flags) && mddev->kobj.sd) { 578 sprintf(nm, "rd%d", rdev->raid_disk); 579 sysfs_remove_link(&mddev->kobj, nm); 580 } 581 } 582 583 /* 584 * iterates through some rdev ringlist. It's safe to remove the 585 * current 'rdev'. Dont touch 'tmp' though. 586 */ 587 #define rdev_for_each_list(rdev, tmp, head) \ 588 list_for_each_entry_safe(rdev, tmp, head, same_set) 589 590 /* 591 * iterates through the 'same array disks' ringlist 592 */ 593 #define rdev_for_each(rdev, mddev) \ 594 list_for_each_entry(rdev, &((mddev)->disks), same_set) 595 596 #define rdev_for_each_safe(rdev, tmp, mddev) \ 597 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) 598 599 #define rdev_for_each_rcu(rdev, mddev) \ 600 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) 601 602 struct md_thread { 603 void (*run) (struct md_thread *thread); 604 struct mddev *mddev; 605 wait_queue_head_t wqueue; 606 unsigned long flags; 607 struct task_struct *tsk; 608 unsigned long timeout; 609 void *private; 610 }; 611 612 #define THREAD_WAKEUP 0 613 614 static inline void safe_put_page(struct page *p) 615 { 616 if (p) put_page(p); 617 } 618 619 extern int register_md_personality(struct md_personality *p); 620 extern int unregister_md_personality(struct md_personality *p); 621 extern int register_md_cluster_operations(struct md_cluster_operations *ops, 622 struct module *module); 623 extern int unregister_md_cluster_operations(void); 624 extern int md_setup_cluster(struct mddev *mddev, int nodes); 625 extern void md_cluster_stop(struct mddev *mddev); 626 extern struct md_thread *md_register_thread( 627 void (*run)(struct md_thread *thread), 628 struct mddev *mddev, 629 const char *name); 630 extern void md_unregister_thread(struct md_thread **threadp); 631 extern void md_wakeup_thread(struct md_thread *thread); 632 extern void md_check_recovery(struct mddev *mddev); 633 extern void md_reap_sync_thread(struct mddev *mddev); 634 extern void md_write_start(struct mddev *mddev, struct bio *bi); 635 extern void md_write_end(struct mddev *mddev); 636 extern void md_done_sync(struct mddev *mddev, int blocks, int ok); 637 extern void md_error(struct mddev *mddev, struct md_rdev *rdev); 638 extern void md_finish_reshape(struct mddev *mddev); 639 640 extern int mddev_congested(struct mddev *mddev, int bits); 641 extern void md_flush_request(struct mddev *mddev, struct bio *bio); 642 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev, 643 sector_t sector, int size, struct page *page); 644 extern void md_super_wait(struct mddev *mddev); 645 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, 646 struct page *page, int rw, bool metadata_op); 647 extern void md_do_sync(struct md_thread *thread); 648 extern void md_new_event(struct mddev *mddev); 649 extern int md_allow_write(struct mddev *mddev); 650 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); 651 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); 652 extern int md_check_no_bitmap(struct mddev *mddev); 653 extern int md_integrity_register(struct mddev *mddev); 654 extern void md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev); 655 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale); 656 657 extern void mddev_init(struct mddev *mddev); 658 extern int md_run(struct mddev *mddev); 659 extern void md_stop(struct mddev *mddev); 660 extern void md_stop_writes(struct mddev *mddev); 661 extern int md_rdev_init(struct md_rdev *rdev); 662 extern void md_rdev_clear(struct md_rdev *rdev); 663 664 extern void mddev_suspend(struct mddev *mddev); 665 extern void mddev_resume(struct mddev *mddev); 666 extern struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask, 667 struct mddev *mddev); 668 extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs, 669 struct mddev *mddev); 670 671 extern void md_unplug(struct blk_plug_cb *cb, bool from_schedule); 672 extern void md_reload_sb(struct mddev *mddev); 673 extern void md_update_sb(struct mddev *mddev, int force); 674 extern void md_kick_rdev_from_array(struct md_rdev * rdev); 675 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr); 676 static inline int mddev_check_plugged(struct mddev *mddev) 677 { 678 return !!blk_check_plugged(md_unplug, mddev, 679 sizeof(struct blk_plug_cb)); 680 } 681 682 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev) 683 { 684 int faulty = test_bit(Faulty, &rdev->flags); 685 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) { 686 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 687 md_wakeup_thread(mddev->thread); 688 } 689 } 690 691 extern struct md_cluster_operations *md_cluster_ops; 692 static inline int mddev_is_clustered(struct mddev *mddev) 693 { 694 return mddev->cluster_info && mddev->bitmap_info.nodes > 1; 695 } 696 #endif /* _MD_MD_H */ 697