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 */ 139 WriteMostly, /* Avoid reading if at all possible */ 140 AutoDetected, /* added by auto-detect */ 141 Blocked, /* An error occurred but has not yet 142 * been acknowledged by the metadata 143 * handler, so don't allow writes 144 * until it is cleared */ 145 WriteErrorSeen, /* A write error has been seen on this 146 * device 147 */ 148 FaultRecorded, /* Intermediate state for clearing 149 * Blocked. The Fault is/will-be 150 * recorded in the metadata, but that 151 * metadata hasn't been stored safely 152 * on disk yet. 153 */ 154 BlockedBadBlocks, /* A writer is blocked because they 155 * found an unacknowledged bad-block. 156 * This can safely be cleared at any 157 * time, and the writer will re-check. 158 * It may be set at any time, and at 159 * worst the writer will timeout and 160 * re-check. So setting it as 161 * accurately as possible is good, but 162 * not absolutely critical. 163 */ 164 WantReplacement, /* This device is a candidate to be 165 * hot-replaced, either because it has 166 * reported some faults, or because 167 * of explicit request. 168 */ 169 Replacement, /* This device is a replacement for 170 * a want_replacement device with same 171 * raid_disk number. 172 */ 173 Candidate, /* For clustered environments only: 174 * This device is seen locally but not 175 * by the whole cluster 176 */ 177 Journal, /* This device is used as journal for 178 * raid-5/6. 179 * Usually, this device should be faster 180 * than other devices in the array 181 */ 182 ClusterRemove, 183 RemoveSynchronized, /* synchronize_rcu() was called after 184 * this device was known to be faulty, 185 * so it is safe to remove without 186 * another synchronize_rcu() call. 187 */ 188 ExternalBbl, /* External metadata provides bad 189 * block management for a disk 190 */ 191 FailFast, /* Minimal retries should be attempted on 192 * this device, so use REQ_FAILFAST_DEV. 193 * Also don't try to repair failed reads. 194 * It is expects that no bad block log 195 * is present. 196 */ 197 LastDev, /* Seems to be the last working dev as 198 * it didn't fail, so don't use FailFast 199 * any more for metadata 200 */ 201 }; 202 203 static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors, 204 sector_t *first_bad, int *bad_sectors) 205 { 206 if (unlikely(rdev->badblocks.count)) { 207 int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s, 208 sectors, 209 first_bad, bad_sectors); 210 if (rv) 211 *first_bad -= rdev->data_offset; 212 return rv; 213 } 214 return 0; 215 } 216 extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 217 int is_new); 218 extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors, 219 int is_new); 220 struct md_cluster_info; 221 222 /* change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added */ 223 enum mddev_flags { 224 MD_ARRAY_FIRST_USE, /* First use of array, needs initialization */ 225 MD_CLOSING, /* If set, we are closing the array, do not open 226 * it then */ 227 MD_JOURNAL_CLEAN, /* A raid with journal is already clean */ 228 MD_HAS_JOURNAL, /* The raid array has journal feature set */ 229 MD_CLUSTER_RESYNC_LOCKED, /* cluster raid only, which means node 230 * already took resync lock, need to 231 * release the lock */ 232 MD_FAILFAST_SUPPORTED, /* Using MD_FAILFAST on metadata writes is 233 * supported as calls to md_error() will 234 * never cause the array to become failed. 235 */ 236 MD_HAS_PPL, /* The raid array has PPL feature set */ 237 }; 238 239 enum mddev_sb_flags { 240 MD_SB_CHANGE_DEVS, /* Some device status has changed */ 241 MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */ 242 MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */ 243 MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */ 244 }; 245 246 struct mddev { 247 void *private; 248 struct md_personality *pers; 249 dev_t unit; 250 int md_minor; 251 struct list_head disks; 252 unsigned long flags; 253 unsigned long sb_flags; 254 255 int suspended; 256 atomic_t active_io; 257 int ro; 258 int sysfs_active; /* set when sysfs deletes 259 * are happening, so run/ 260 * takeover/stop are not safe 261 */ 262 struct gendisk *gendisk; 263 264 struct kobject kobj; 265 int hold_active; 266 #define UNTIL_IOCTL 1 267 #define UNTIL_STOP 2 268 269 /* Superblock information */ 270 int major_version, 271 minor_version, 272 patch_version; 273 int persistent; 274 int external; /* metadata is 275 * managed externally */ 276 char metadata_type[17]; /* externally set*/ 277 int chunk_sectors; 278 time64_t ctime, utime; 279 int level, layout; 280 char clevel[16]; 281 int raid_disks; 282 int max_disks; 283 sector_t dev_sectors; /* used size of 284 * component devices */ 285 sector_t array_sectors; /* exported array size */ 286 int external_size; /* size managed 287 * externally */ 288 __u64 events; 289 /* If the last 'event' was simply a clean->dirty transition, and 290 * we didn't write it to the spares, then it is safe and simple 291 * to just decrement the event count on a dirty->clean transition. 292 * So we record that possibility here. 293 */ 294 int can_decrease_events; 295 296 char uuid[16]; 297 298 /* If the array is being reshaped, we need to record the 299 * new shape and an indication of where we are up to. 300 * This is written to the superblock. 301 * If reshape_position is MaxSector, then no reshape is happening (yet). 302 */ 303 sector_t reshape_position; 304 int delta_disks, new_level, new_layout; 305 int new_chunk_sectors; 306 int reshape_backwards; 307 308 struct md_thread *thread; /* management thread */ 309 struct md_thread *sync_thread; /* doing resync or reconstruct */ 310 311 /* 'last_sync_action' is initialized to "none". It is set when a 312 * sync operation (i.e "data-check", "requested-resync", "resync", 313 * "recovery", or "reshape") is started. It holds this value even 314 * when the sync thread is "frozen" (interrupted) or "idle" (stopped 315 * or finished). It is overwritten when a new sync operation is begun. 316 */ 317 char *last_sync_action; 318 sector_t curr_resync; /* last block scheduled */ 319 /* As resync requests can complete out of order, we cannot easily track 320 * how much resync has been completed. So we occasionally pause until 321 * everything completes, then set curr_resync_completed to curr_resync. 322 * As such it may be well behind the real resync mark, but it is a value 323 * we are certain of. 324 */ 325 sector_t curr_resync_completed; 326 unsigned long resync_mark; /* a recent timestamp */ 327 sector_t resync_mark_cnt;/* blocks written at resync_mark */ 328 sector_t curr_mark_cnt; /* blocks scheduled now */ 329 330 sector_t resync_max_sectors; /* may be set by personality */ 331 332 atomic64_t resync_mismatches; /* count of sectors where 333 * parity/replica mismatch found 334 */ 335 336 /* allow user-space to request suspension of IO to regions of the array */ 337 sector_t suspend_lo; 338 sector_t suspend_hi; 339 /* if zero, use the system-wide default */ 340 int sync_speed_min; 341 int sync_speed_max; 342 343 /* resync even though the same disks are shared among md-devices */ 344 int parallel_resync; 345 346 int ok_start_degraded; 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 */ 376 377 atomic_t recovery_active; /* blocks scheduled, but not written */ 378 wait_queue_head_t recovery_wait; 379 sector_t recovery_cp; 380 sector_t resync_min; /* user requested sync 381 * starts here */ 382 sector_t resync_max; /* resync should pause 383 * when it gets here */ 384 385 struct kernfs_node *sysfs_state; /* handle for 'array_state' 386 * file in sysfs. 387 */ 388 struct kernfs_node *sysfs_action; /* handle for 'sync_action' */ 389 390 struct work_struct del_work; /* used for delayed sysfs removal */ 391 392 /* "lock" protects: 393 * flush_bio transition from NULL to !NULL 394 * rdev superblocks, events 395 * clearing MD_CHANGE_* 396 * in_sync - and related safemode and MD_CHANGE changes 397 * pers (also protected by reconfig_mutex and pending IO). 398 * clearing ->bitmap 399 * clearing ->bitmap_info.file 400 * changing ->resync_{min,max} 401 * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max}) 402 */ 403 spinlock_t lock; 404 wait_queue_head_t sb_wait; /* for waiting on superblock updates */ 405 atomic_t pending_writes; /* number of active superblock writes */ 406 407 unsigned int safemode; /* if set, update "clean" superblock 408 * when no writes pending. 409 */ 410 unsigned int safemode_delay; 411 struct timer_list safemode_timer; 412 struct percpu_ref writes_pending; 413 int sync_checkers; /* # of threads checking writes_pending */ 414 struct request_queue *queue; /* for plugging ... */ 415 416 struct bitmap *bitmap; /* the bitmap for the device */ 417 struct { 418 struct file *file; /* the bitmap file */ 419 loff_t offset; /* offset from superblock of 420 * start of bitmap. May be 421 * negative, but not '0' 422 * For external metadata, offset 423 * from start of device. 424 */ 425 unsigned long space; /* space available at this offset */ 426 loff_t default_offset; /* this is the offset to use when 427 * hot-adding a bitmap. It should 428 * eventually be settable by sysfs. 429 */ 430 unsigned long default_space; /* space available at 431 * default offset */ 432 struct mutex mutex; 433 unsigned long chunksize; 434 unsigned long daemon_sleep; /* how many jiffies between updates? */ 435 unsigned long max_write_behind; /* write-behind mode */ 436 int external; 437 int nodes; /* Maximum number of nodes in the cluster */ 438 char cluster_name[64]; /* Name of the cluster */ 439 } bitmap_info; 440 441 atomic_t max_corr_read_errors; /* max read retries */ 442 struct list_head all_mddevs; 443 444 struct attribute_group *to_remove; 445 446 struct bio_set *bio_set; 447 struct bio_set *sync_set; /* for sync operations like 448 * metadata and bitmap writes 449 */ 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_PREFLUSH 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 unsigned int good_device_nr; /* good device num within cluster raid */ 462 }; 463 464 enum recovery_flags { 465 /* 466 * If neither SYNC or RESHAPE are set, then it is a recovery. 467 */ 468 MD_RECOVERY_RUNNING, /* a thread is running, or about to be started */ 469 MD_RECOVERY_SYNC, /* actually doing a resync, not a recovery */ 470 MD_RECOVERY_RECOVER, /* doing recovery, or need to try it. */ 471 MD_RECOVERY_INTR, /* resync needs to be aborted for some reason */ 472 MD_RECOVERY_DONE, /* thread is done and is waiting to be reaped */ 473 MD_RECOVERY_NEEDED, /* we might need to start a resync/recover */ 474 MD_RECOVERY_REQUESTED, /* user-space has requested a sync (used with SYNC) */ 475 MD_RECOVERY_CHECK, /* user-space request for check-only, no repair */ 476 MD_RECOVERY_RESHAPE, /* A reshape is happening */ 477 MD_RECOVERY_FROZEN, /* User request to abort, and not restart, any action */ 478 MD_RECOVERY_ERROR, /* sync-action interrupted because io-error */ 479 }; 480 481 static inline int __must_check mddev_lock(struct mddev *mddev) 482 { 483 return mutex_lock_interruptible(&mddev->reconfig_mutex); 484 } 485 486 /* Sometimes we need to take the lock in a situation where 487 * failure due to interrupts is not acceptable. 488 */ 489 static inline void mddev_lock_nointr(struct mddev *mddev) 490 { 491 mutex_lock(&mddev->reconfig_mutex); 492 } 493 494 static inline int mddev_is_locked(struct mddev *mddev) 495 { 496 return mutex_is_locked(&mddev->reconfig_mutex); 497 } 498 499 static inline int mddev_trylock(struct mddev *mddev) 500 { 501 return mutex_trylock(&mddev->reconfig_mutex); 502 } 503 extern void mddev_unlock(struct mddev *mddev); 504 505 static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors) 506 { 507 atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io); 508 } 509 510 struct md_personality 511 { 512 char *name; 513 int level; 514 struct list_head list; 515 struct module *owner; 516 bool (*make_request)(struct mddev *mddev, struct bio *bio); 517 int (*run)(struct mddev *mddev); 518 void (*free)(struct mddev *mddev, void *priv); 519 void (*status)(struct seq_file *seq, struct mddev *mddev); 520 /* error_handler must set ->faulty and clear ->in_sync 521 * if appropriate, and should abort recovery if needed 522 */ 523 void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev); 524 int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev); 525 int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev); 526 int (*spare_active) (struct mddev *mddev); 527 sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped); 528 int (*resize) (struct mddev *mddev, sector_t sectors); 529 sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks); 530 int (*check_reshape) (struct mddev *mddev); 531 int (*start_reshape) (struct mddev *mddev); 532 void (*finish_reshape) (struct mddev *mddev); 533 /* quiesce moves between quiescence states 534 * 0 - fully active 535 * 1 - no new requests allowed 536 * others - reserved 537 */ 538 void (*quiesce) (struct mddev *mddev, int state); 539 /* takeover is used to transition an array from one 540 * personality to another. The new personality must be able 541 * to handle the data in the current layout. 542 * e.g. 2drive raid1 -> 2drive raid5 543 * ndrive raid5 -> degraded n+1drive raid6 with special layout 544 * If the takeover succeeds, a new 'private' structure is returned. 545 * This needs to be installed and then ->run used to activate the 546 * array. 547 */ 548 void *(*takeover) (struct mddev *mddev); 549 /* congested implements bdi.congested_fn(). 550 * Will not be called while array is 'suspended' */ 551 int (*congested)(struct mddev *mddev, int bits); 552 /* Changes the consistency policy of an active array. */ 553 int (*change_consistency_policy)(struct mddev *mddev, const char *buf); 554 }; 555 556 struct md_sysfs_entry { 557 struct attribute attr; 558 ssize_t (*show)(struct mddev *, char *); 559 ssize_t (*store)(struct mddev *, const char *, size_t); 560 }; 561 extern struct attribute_group md_bitmap_group; 562 563 static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name) 564 { 565 if (sd) 566 return sysfs_get_dirent(sd, name); 567 return sd; 568 } 569 static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd) 570 { 571 if (sd) 572 sysfs_notify_dirent(sd); 573 } 574 575 static inline char * mdname (struct mddev * mddev) 576 { 577 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; 578 } 579 580 static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev) 581 { 582 char nm[20]; 583 if (!test_bit(Replacement, &rdev->flags) && 584 !test_bit(Journal, &rdev->flags) && 585 mddev->kobj.sd) { 586 sprintf(nm, "rd%d", rdev->raid_disk); 587 return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); 588 } else 589 return 0; 590 } 591 592 static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev) 593 { 594 char nm[20]; 595 if (!test_bit(Replacement, &rdev->flags) && 596 !test_bit(Journal, &rdev->flags) && 597 mddev->kobj.sd) { 598 sprintf(nm, "rd%d", rdev->raid_disk); 599 sysfs_remove_link(&mddev->kobj, nm); 600 } 601 } 602 603 /* 604 * iterates through some rdev ringlist. It's safe to remove the 605 * current 'rdev'. Dont touch 'tmp' though. 606 */ 607 #define rdev_for_each_list(rdev, tmp, head) \ 608 list_for_each_entry_safe(rdev, tmp, head, same_set) 609 610 /* 611 * iterates through the 'same array disks' ringlist 612 */ 613 #define rdev_for_each(rdev, mddev) \ 614 list_for_each_entry(rdev, &((mddev)->disks), same_set) 615 616 #define rdev_for_each_safe(rdev, tmp, mddev) \ 617 list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) 618 619 #define rdev_for_each_rcu(rdev, mddev) \ 620 list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) 621 622 struct md_thread { 623 void (*run) (struct md_thread *thread); 624 struct mddev *mddev; 625 wait_queue_head_t wqueue; 626 unsigned long flags; 627 struct task_struct *tsk; 628 unsigned long timeout; 629 void *private; 630 }; 631 632 #define THREAD_WAKEUP 0 633 634 static inline void safe_put_page(struct page *p) 635 { 636 if (p) put_page(p); 637 } 638 639 extern int register_md_personality(struct md_personality *p); 640 extern int unregister_md_personality(struct md_personality *p); 641 extern int register_md_cluster_operations(struct md_cluster_operations *ops, 642 struct module *module); 643 extern int unregister_md_cluster_operations(void); 644 extern int md_setup_cluster(struct mddev *mddev, int nodes); 645 extern void md_cluster_stop(struct mddev *mddev); 646 extern struct md_thread *md_register_thread( 647 void (*run)(struct md_thread *thread), 648 struct mddev *mddev, 649 const char *name); 650 extern void md_unregister_thread(struct md_thread **threadp); 651 extern void md_wakeup_thread(struct md_thread *thread); 652 extern void md_check_recovery(struct mddev *mddev); 653 extern void md_reap_sync_thread(struct mddev *mddev); 654 extern int mddev_init_writes_pending(struct mddev *mddev); 655 extern bool md_write_start(struct mddev *mddev, struct bio *bi); 656 extern void md_write_inc(struct mddev *mddev, struct bio *bi); 657 extern void md_write_end(struct mddev *mddev); 658 extern void md_done_sync(struct mddev *mddev, int blocks, int ok); 659 extern void md_error(struct mddev *mddev, struct md_rdev *rdev); 660 extern void md_finish_reshape(struct mddev *mddev); 661 662 extern int mddev_congested(struct mddev *mddev, int bits); 663 extern void md_flush_request(struct mddev *mddev, struct bio *bio); 664 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev, 665 sector_t sector, int size, struct page *page); 666 extern int md_super_wait(struct mddev *mddev); 667 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, 668 struct page *page, int op, int op_flags, 669 bool metadata_op); 670 extern void md_do_sync(struct md_thread *thread); 671 extern void md_new_event(struct mddev *mddev); 672 extern void md_allow_write(struct mddev *mddev); 673 extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); 674 extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); 675 extern int md_check_no_bitmap(struct mddev *mddev); 676 extern int md_integrity_register(struct mddev *mddev); 677 extern int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev); 678 extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale); 679 680 extern void mddev_init(struct mddev *mddev); 681 extern int md_run(struct mddev *mddev); 682 extern void md_stop(struct mddev *mddev); 683 extern void md_stop_writes(struct mddev *mddev); 684 extern int md_rdev_init(struct md_rdev *rdev); 685 extern void md_rdev_clear(struct md_rdev *rdev); 686 687 extern void mddev_suspend(struct mddev *mddev); 688 extern void mddev_resume(struct mddev *mddev); 689 extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs, 690 struct mddev *mddev); 691 692 extern void md_reload_sb(struct mddev *mddev, int raid_disk); 693 extern void md_update_sb(struct mddev *mddev, int force); 694 extern void md_kick_rdev_from_array(struct md_rdev * rdev); 695 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr); 696 697 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev) 698 { 699 int faulty = test_bit(Faulty, &rdev->flags); 700 if (atomic_dec_and_test(&rdev->nr_pending) && faulty) { 701 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 702 md_wakeup_thread(mddev->thread); 703 } 704 } 705 706 extern struct md_cluster_operations *md_cluster_ops; 707 static inline int mddev_is_clustered(struct mddev *mddev) 708 { 709 return mddev->cluster_info && mddev->bitmap_info.nodes > 1; 710 } 711 712 /* clear unsupported mddev_flags */ 713 static inline void mddev_clear_unsupported_flags(struct mddev *mddev, 714 unsigned long unsupported_flags) 715 { 716 mddev->flags &= ~unsupported_flags; 717 } 718 719 static inline void mddev_check_writesame(struct mddev *mddev, struct bio *bio) 720 { 721 if (bio_op(bio) == REQ_OP_WRITE_SAME && 722 !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors) 723 mddev->queue->limits.max_write_same_sectors = 0; 724 } 725 726 static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio) 727 { 728 if (bio_op(bio) == REQ_OP_WRITE_ZEROES && 729 !bdev_get_queue(bio->bi_bdev)->limits.max_write_zeroes_sectors) 730 mddev->queue->limits.max_write_zeroes_sectors = 0; 731 } 732 733 /* Maximum size of each resync request */ 734 #define RESYNC_BLOCK_SIZE (64*1024) 735 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) 736 737 /* for managing resync I/O pages */ 738 struct resync_pages { 739 unsigned idx; /* for get/put page from the pool */ 740 void *raid_bio; 741 struct page *pages[RESYNC_PAGES]; 742 }; 743 744 static inline int resync_alloc_pages(struct resync_pages *rp, 745 gfp_t gfp_flags) 746 { 747 int i; 748 749 for (i = 0; i < RESYNC_PAGES; i++) { 750 rp->pages[i] = alloc_page(gfp_flags); 751 if (!rp->pages[i]) 752 goto out_free; 753 } 754 755 return 0; 756 757 out_free: 758 while (--i >= 0) 759 put_page(rp->pages[i]); 760 return -ENOMEM; 761 } 762 763 static inline void resync_free_pages(struct resync_pages *rp) 764 { 765 int i; 766 767 for (i = 0; i < RESYNC_PAGES; i++) 768 put_page(rp->pages[i]); 769 } 770 771 static inline void resync_get_all_pages(struct resync_pages *rp) 772 { 773 int i; 774 775 for (i = 0; i < RESYNC_PAGES; i++) 776 get_page(rp->pages[i]); 777 } 778 779 static inline struct page *resync_fetch_page(struct resync_pages *rp, 780 unsigned idx) 781 { 782 if (WARN_ON_ONCE(idx >= RESYNC_PAGES)) 783 return NULL; 784 return rp->pages[idx]; 785 } 786 #endif /* _MD_MD_H */ 787