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1 : : /* SPDX-License-Identifier: GPL-2.0-or-later */
2 : : /*
3 : : md.h : kernel internal structure of the Linux MD driver
4 : : Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
5 : :
6 : : */
7 : :
8 : : #ifndef _MD_MD_H
9 : : #define _MD_MD_H
10 : :
11 : : #include <linux/blkdev.h>
12 : : #include <linux/backing-dev.h>
13 : : #include <linux/badblocks.h>
14 : : #include <linux/kobject.h>
15 : : #include <linux/list.h>
16 : : #include <linux/mm.h>
17 : : #include <linux/mutex.h>
18 : : #include <linux/timer.h>
19 : : #include <linux/wait.h>
20 : : #include <linux/workqueue.h>
21 : : #include "md-cluster.h"
22 : :
23 : : #define MaxSector (~(sector_t)0)
24 : :
25 : : /*
26 : : * These flags should really be called "NO_RETRY" rather than
27 : : * "FAILFAST" because they don't make any promise about time lapse,
28 : : * only about the number of retries, which will be zero.
29 : : * REQ_FAILFAST_DRIVER is not included because
30 : : * Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.")
31 : : * seems to suggest that the errors it avoids retrying should usually
32 : : * be retried.
33 : : */
34 : : #define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT)
35 : :
36 : : /*
37 : : * The struct embedded in rdev is used to serialize IO.
38 : : */
39 : : struct serial_in_rdev {
40 : : struct rb_root_cached serial_rb;
41 : : spinlock_t serial_lock;
42 : : wait_queue_head_t serial_io_wait;
43 : : };
44 : :
45 : : /*
46 : : * MD's 'extended' device
47 : : */
48 : : struct md_rdev {
49 : : struct list_head same_set; /* RAID devices within the same set */
50 : :
51 : : sector_t sectors; /* Device size (in 512bytes sectors) */
52 : : struct mddev *mddev; /* RAID array if running */
53 : : int last_events; /* IO event timestamp */
54 : :
55 : : /*
56 : : * If meta_bdev is non-NULL, it means that a separate device is
57 : : * being used to store the metadata (superblock/bitmap) which
58 : : * would otherwise be contained on the same device as the data (bdev).
59 : : */
60 : : struct block_device *meta_bdev;
61 : : struct block_device *bdev; /* block device handle */
62 : :
63 : : struct page *sb_page, *bb_page;
64 : : int sb_loaded;
65 : : __u64 sb_events;
66 : : sector_t data_offset; /* start of data in array */
67 : : sector_t new_data_offset;/* only relevant while reshaping */
68 : : sector_t sb_start; /* offset of the super block (in 512byte sectors) */
69 : : int sb_size; /* bytes in the superblock */
70 : : int preferred_minor; /* autorun support */
71 : :
72 : : struct kobject kobj;
73 : :
74 : : /* A device can be in one of three states based on two flags:
75 : : * Not working: faulty==1 in_sync==0
76 : : * Fully working: faulty==0 in_sync==1
77 : : * Working, but not
78 : : * in sync with array
79 : : * faulty==0 in_sync==0
80 : : *
81 : : * It can never have faulty==1, in_sync==1
82 : : * This reduces the burden of testing multiple flags in many cases
83 : : */
84 : :
85 : : unsigned long flags; /* bit set of 'enum flag_bits' bits. */
86 : : wait_queue_head_t blocked_wait;
87 : :
88 : : int desc_nr; /* descriptor index in the superblock */
89 : : int raid_disk; /* role of device in array */
90 : : int new_raid_disk; /* role that the device will have in
91 : : * the array after a level-change completes.
92 : : */
93 : : int saved_raid_disk; /* role that device used to have in the
94 : : * array and could again if we did a partial
95 : : * resync from the bitmap
96 : : */
97 : : union {
98 : : sector_t recovery_offset;/* If this device has been partially
99 : : * recovered, this is where we were
100 : : * up to.
101 : : */
102 : : sector_t journal_tail; /* If this device is a journal device,
103 : : * this is the journal tail (journal
104 : : * recovery start point)
105 : : */
106 : : };
107 : :
108 : : atomic_t nr_pending; /* number of pending requests.
109 : : * only maintained for arrays that
110 : : * support hot removal
111 : : */
112 : : atomic_t read_errors; /* number of consecutive read errors that
113 : : * we have tried to ignore.
114 : : */
115 : : time64_t last_read_error; /* monotonic time since our
116 : : * last read error
117 : : */
118 : : atomic_t corrected_errors; /* number of corrected read errors,
119 : : * for reporting to userspace and storing
120 : : * in superblock.
121 : : */
122 : :
123 : : struct serial_in_rdev *serial; /* used for raid1 io serialization */
124 : :
125 : : struct work_struct del_work; /* used for delayed sysfs removal */
126 : :
127 : : struct kernfs_node *sysfs_state; /* handle for 'state'
128 : : * sysfs entry */
129 : :
130 : : struct badblocks badblocks;
131 : :
132 : : struct {
133 : : short offset; /* Offset from superblock to start of PPL.
134 : : * Not used by external metadata. */
135 : : unsigned int size; /* Size in sectors of the PPL space */
136 : : sector_t sector; /* First sector of the PPL space */
137 : : } ppl;
138 : : };
139 : : enum flag_bits {
140 : : Faulty, /* device is known to have a fault */
141 : : In_sync, /* device is in_sync with rest of array */
142 : : Bitmap_sync, /* ..actually, not quite In_sync. Need a
143 : : * bitmap-based recovery to get fully in sync.
144 : : * The bit is only meaningful before device
145 : : * has been passed to pers->hot_add_disk.
146 : : */
147 : : WriteMostly, /* Avoid reading if at all possible */
148 : : AutoDetected, /* added by auto-detect */
149 : : Blocked, /* An error occurred but has not yet
150 : : * been acknowledged by the metadata
151 : : * handler, so don't allow writes
152 : : * until it is cleared */
153 : : WriteErrorSeen, /* A write error has been seen on this
154 : : * device
155 : : */
156 : : FaultRecorded, /* Intermediate state for clearing
157 : : * Blocked. The Fault is/will-be
158 : : * recorded in the metadata, but that
159 : : * metadata hasn't been stored safely
160 : : * on disk yet.
161 : : */
162 : : BlockedBadBlocks, /* A writer is blocked because they
163 : : * found an unacknowledged bad-block.
164 : : * This can safely be cleared at any
165 : : * time, and the writer will re-check.
166 : : * It may be set at any time, and at
167 : : * worst the writer will timeout and
168 : : * re-check. So setting it as
169 : : * accurately as possible is good, but
170 : : * not absolutely critical.
171 : : */
172 : : WantReplacement, /* This device is a candidate to be
173 : : * hot-replaced, either because it has
174 : : * reported some faults, or because
175 : : * of explicit request.
176 : : */
177 : : Replacement, /* This device is a replacement for
178 : : * a want_replacement device with same
179 : : * raid_disk number.
180 : : */
181 : : Candidate, /* For clustered environments only:
182 : : * This device is seen locally but not
183 : : * by the whole cluster
184 : : */
185 : : Journal, /* This device is used as journal for
186 : : * raid-5/6.
187 : : * Usually, this device should be faster
188 : : * than other devices in the array
189 : : */
190 : : ClusterRemove,
191 : : RemoveSynchronized, /* synchronize_rcu() was called after
192 : : * this device was known to be faulty,
193 : : * so it is safe to remove without
194 : : * another synchronize_rcu() call.
195 : : */
196 : : ExternalBbl, /* External metadata provides bad
197 : : * block management for a disk
198 : : */
199 : : FailFast, /* Minimal retries should be attempted on
200 : : * this device, so use REQ_FAILFAST_DEV.
201 : : * Also don't try to repair failed reads.
202 : : * It is expects that no bad block log
203 : : * is present.
204 : : */
205 : : LastDev, /* Seems to be the last working dev as
206 : : * it didn't fail, so don't use FailFast
207 : : * any more for metadata
208 : : */
209 : : CollisionCheck, /*
210 : : * check if there is collision between raid1
211 : : * serial bios.
212 : : */
213 : : };
214 : :
215 : : static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors,
216 : : sector_t *first_bad, int *bad_sectors)
217 : : {
218 : : if (unlikely(rdev->badblocks.count)) {
219 : : int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s,
220 : : sectors,
221 : : first_bad, bad_sectors);
222 : : if (rv)
223 : : *first_bad -= rdev->data_offset;
224 : : return rv;
225 : : }
226 : : return 0;
227 : : }
228 : : extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
229 : : int is_new);
230 : : extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
231 : : int is_new);
232 : : struct md_cluster_info;
233 : :
234 : : /* change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added */
235 : : enum mddev_flags {
236 : : MD_ARRAY_FIRST_USE, /* First use of array, needs initialization */
237 : : MD_CLOSING, /* If set, we are closing the array, do not open
238 : : * it then */
239 : : MD_JOURNAL_CLEAN, /* A raid with journal is already clean */
240 : : MD_HAS_JOURNAL, /* The raid array has journal feature set */
241 : : MD_CLUSTER_RESYNC_LOCKED, /* cluster raid only, which means node
242 : : * already took resync lock, need to
243 : : * release the lock */
244 : : MD_FAILFAST_SUPPORTED, /* Using MD_FAILFAST on metadata writes is
245 : : * supported as calls to md_error() will
246 : : * never cause the array to become failed.
247 : : */
248 : : MD_HAS_PPL, /* The raid array has PPL feature set */
249 : : MD_HAS_MULTIPLE_PPLS, /* The raid array has multiple PPLs feature set */
250 : : MD_ALLOW_SB_UPDATE, /* md_check_recovery is allowed to update
251 : : * the metadata without taking reconfig_mutex.
252 : : */
253 : : MD_UPDATING_SB, /* md_check_recovery is updating the metadata
254 : : * without explicitly holding reconfig_mutex.
255 : : */
256 : : MD_NOT_READY, /* do_md_run() is active, so 'array_state'
257 : : * must not report that array is ready yet
258 : : */
259 : : MD_BROKEN, /* This is used in RAID-0/LINEAR only, to stop
260 : : * I/O in case an array member is gone/failed.
261 : : */
262 : : };
263 : :
264 : : enum mddev_sb_flags {
265 : : MD_SB_CHANGE_DEVS, /* Some device status has changed */
266 : : MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */
267 : : MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */
268 : : MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */
269 : : };
270 : :
271 : : #define NR_SERIAL_INFOS 8
272 : : /* record current range of serialize IOs */
273 : : struct serial_info {
274 : : struct rb_node node;
275 : : sector_t start; /* start sector of rb node */
276 : : sector_t last; /* end sector of rb node */
277 : : sector_t _subtree_last; /* highest sector in subtree of rb node */
278 : : };
279 : :
280 : : struct mddev {
281 : : void *private;
282 : : struct md_personality *pers;
283 : : dev_t unit;
284 : : int md_minor;
285 : : struct list_head disks;
286 : : unsigned long flags;
287 : : unsigned long sb_flags;
288 : :
289 : : int suspended;
290 : : atomic_t active_io;
291 : : int ro;
292 : : int sysfs_active; /* set when sysfs deletes
293 : : * are happening, so run/
294 : : * takeover/stop are not safe
295 : : */
296 : : struct gendisk *gendisk;
297 : :
298 : : struct kobject kobj;
299 : : int hold_active;
300 : : #define UNTIL_IOCTL 1
301 : : #define UNTIL_STOP 2
302 : :
303 : : /* Superblock information */
304 : : int major_version,
305 : : minor_version,
306 : : patch_version;
307 : : int persistent;
308 : : int external; /* metadata is
309 : : * managed externally */
310 : : char metadata_type[17]; /* externally set*/
311 : : int chunk_sectors;
312 : : time64_t ctime, utime;
313 : : int level, layout;
314 : : char clevel[16];
315 : : int raid_disks;
316 : : int max_disks;
317 : : sector_t dev_sectors; /* used size of
318 : : * component devices */
319 : : sector_t array_sectors; /* exported array size */
320 : : int external_size; /* size managed
321 : : * externally */
322 : : __u64 events;
323 : : /* If the last 'event' was simply a clean->dirty transition, and
324 : : * we didn't write it to the spares, then it is safe and simple
325 : : * to just decrement the event count on a dirty->clean transition.
326 : : * So we record that possibility here.
327 : : */
328 : : int can_decrease_events;
329 : :
330 : : char uuid[16];
331 : :
332 : : /* If the array is being reshaped, we need to record the
333 : : * new shape and an indication of where we are up to.
334 : : * This is written to the superblock.
335 : : * If reshape_position is MaxSector, then no reshape is happening (yet).
336 : : */
337 : : sector_t reshape_position;
338 : : int delta_disks, new_level, new_layout;
339 : : int new_chunk_sectors;
340 : : int reshape_backwards;
341 : :
342 : : struct md_thread *thread; /* management thread */
343 : : struct md_thread *sync_thread; /* doing resync or reconstruct */
344 : :
345 : : /* 'last_sync_action' is initialized to "none". It is set when a
346 : : * sync operation (i.e "data-check", "requested-resync", "resync",
347 : : * "recovery", or "reshape") is started. It holds this value even
348 : : * when the sync thread is "frozen" (interrupted) or "idle" (stopped
349 : : * or finished). It is overwritten when a new sync operation is begun.
350 : : */
351 : : char *last_sync_action;
352 : : sector_t curr_resync; /* last block scheduled */
353 : : /* As resync requests can complete out of order, we cannot easily track
354 : : * how much resync has been completed. So we occasionally pause until
355 : : * everything completes, then set curr_resync_completed to curr_resync.
356 : : * As such it may be well behind the real resync mark, but it is a value
357 : : * we are certain of.
358 : : */
359 : : sector_t curr_resync_completed;
360 : : unsigned long resync_mark; /* a recent timestamp */
361 : : sector_t resync_mark_cnt;/* blocks written at resync_mark */
362 : : sector_t curr_mark_cnt; /* blocks scheduled now */
363 : :
364 : : sector_t resync_max_sectors; /* may be set by personality */
365 : :
366 : : atomic64_t resync_mismatches; /* count of sectors where
367 : : * parity/replica mismatch found
368 : : */
369 : :
370 : : /* allow user-space to request suspension of IO to regions of the array */
371 : : sector_t suspend_lo;
372 : : sector_t suspend_hi;
373 : : /* if zero, use the system-wide default */
374 : : int sync_speed_min;
375 : : int sync_speed_max;
376 : :
377 : : /* resync even though the same disks are shared among md-devices */
378 : : int parallel_resync;
379 : :
380 : : int ok_start_degraded;
381 : :
382 : : unsigned long recovery;
383 : : /* If a RAID personality determines that recovery (of a particular
384 : : * device) will fail due to a read error on the source device, it
385 : : * takes a copy of this number and does not attempt recovery again
386 : : * until this number changes.
387 : : */
388 : : int recovery_disabled;
389 : :
390 : : int in_sync; /* know to not need resync */
391 : : /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so
392 : : * that we are never stopping an array while it is open.
393 : : * 'reconfig_mutex' protects all other reconfiguration.
394 : : * These locks are separate due to conflicting interactions
395 : : * with bdev->bd_mutex.
396 : : * Lock ordering is:
397 : : * reconfig_mutex -> bd_mutex : e.g. do_md_run -> revalidate_disk
398 : : * bd_mutex -> open_mutex: e.g. __blkdev_get -> md_open
399 : : */
400 : : struct mutex open_mutex;
401 : : struct mutex reconfig_mutex;
402 : : atomic_t active; /* general refcount */
403 : : atomic_t openers; /* number of active opens */
404 : :
405 : : int changed; /* True if we might need to
406 : : * reread partition info */
407 : : int degraded; /* whether md should consider
408 : : * adding a spare
409 : : */
410 : :
411 : : atomic_t recovery_active; /* blocks scheduled, but not written */
412 : : wait_queue_head_t recovery_wait;
413 : : sector_t recovery_cp;
414 : : sector_t resync_min; /* user requested sync
415 : : * starts here */
416 : : sector_t resync_max; /* resync should pause
417 : : * when it gets here */
418 : :
419 : : struct kernfs_node *sysfs_state; /* handle for 'array_state'
420 : : * file in sysfs.
421 : : */
422 : : struct kernfs_node *sysfs_action; /* handle for 'sync_action' */
423 : :
424 : : struct work_struct del_work; /* used for delayed sysfs removal */
425 : :
426 : : /* "lock" protects:
427 : : * flush_bio transition from NULL to !NULL
428 : : * rdev superblocks, events
429 : : * clearing MD_CHANGE_*
430 : : * in_sync - and related safemode and MD_CHANGE changes
431 : : * pers (also protected by reconfig_mutex and pending IO).
432 : : * clearing ->bitmap
433 : : * clearing ->bitmap_info.file
434 : : * changing ->resync_{min,max}
435 : : * setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max})
436 : : */
437 : : spinlock_t lock;
438 : : wait_queue_head_t sb_wait; /* for waiting on superblock updates */
439 : : atomic_t pending_writes; /* number of active superblock writes */
440 : :
441 : : unsigned int safemode; /* if set, update "clean" superblock
442 : : * when no writes pending.
443 : : */
444 : : unsigned int safemode_delay;
445 : : struct timer_list safemode_timer;
446 : : struct percpu_ref writes_pending;
447 : : int sync_checkers; /* # of threads checking writes_pending */
448 : : struct request_queue *queue; /* for plugging ... */
449 : :
450 : : struct bitmap *bitmap; /* the bitmap for the device */
451 : : struct {
452 : : struct file *file; /* the bitmap file */
453 : : loff_t offset; /* offset from superblock of
454 : : * start of bitmap. May be
455 : : * negative, but not '0'
456 : : * For external metadata, offset
457 : : * from start of device.
458 : : */
459 : : unsigned long space; /* space available at this offset */
460 : : loff_t default_offset; /* this is the offset to use when
461 : : * hot-adding a bitmap. It should
462 : : * eventually be settable by sysfs.
463 : : */
464 : : unsigned long default_space; /* space available at
465 : : * default offset */
466 : : struct mutex mutex;
467 : : unsigned long chunksize;
468 : : unsigned long daemon_sleep; /* how many jiffies between updates? */
469 : : unsigned long max_write_behind; /* write-behind mode */
470 : : int external;
471 : : int nodes; /* Maximum number of nodes in the cluster */
472 : : char cluster_name[64]; /* Name of the cluster */
473 : : } bitmap_info;
474 : :
475 : : atomic_t max_corr_read_errors; /* max read retries */
476 : : struct list_head all_mddevs;
477 : :
478 : : struct attribute_group *to_remove;
479 : :
480 : : struct bio_set bio_set;
481 : : struct bio_set sync_set; /* for sync operations like
482 : : * metadata and bitmap writes
483 : : */
484 : :
485 : : /* Generic flush handling.
486 : : * The last to finish preflush schedules a worker to submit
487 : : * the rest of the request (without the REQ_PREFLUSH flag).
488 : : */
489 : : struct bio *flush_bio;
490 : : atomic_t flush_pending;
491 : : ktime_t start_flush, last_flush; /* last_flush is when the last completed
492 : : * flush was started.
493 : : */
494 : : struct work_struct flush_work;
495 : : struct work_struct event_work; /* used by dm to report failure event */
496 : : mempool_t *serial_info_pool;
497 : : void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
498 : : struct md_cluster_info *cluster_info;
499 : : unsigned int good_device_nr; /* good device num within cluster raid */
500 : :
501 : : bool has_superblocks:1;
502 : : bool fail_last_dev:1;
503 : : bool serialize_policy:1;
504 : : };
505 : :
506 : : enum recovery_flags {
507 : : /*
508 : : * If neither SYNC or RESHAPE are set, then it is a recovery.
509 : : */
510 : : MD_RECOVERY_RUNNING, /* a thread is running, or about to be started */
511 : : MD_RECOVERY_SYNC, /* actually doing a resync, not a recovery */
512 : : MD_RECOVERY_RECOVER, /* doing recovery, or need to try it. */
513 : : MD_RECOVERY_INTR, /* resync needs to be aborted for some reason */
514 : : MD_RECOVERY_DONE, /* thread is done and is waiting to be reaped */
515 : : MD_RECOVERY_NEEDED, /* we might need to start a resync/recover */
516 : : MD_RECOVERY_REQUESTED, /* user-space has requested a sync (used with SYNC) */
517 : : MD_RECOVERY_CHECK, /* user-space request for check-only, no repair */
518 : : MD_RECOVERY_RESHAPE, /* A reshape is happening */
519 : : MD_RECOVERY_FROZEN, /* User request to abort, and not restart, any action */
520 : : MD_RECOVERY_ERROR, /* sync-action interrupted because io-error */
521 : : MD_RECOVERY_WAIT, /* waiting for pers->start() to finish */
522 : : MD_RESYNCING_REMOTE, /* remote node is running resync thread */
523 : : };
524 : :
525 : 0 : static inline int __must_check mddev_lock(struct mddev *mddev)
526 : : {
527 : 0 : return mutex_lock_interruptible(&mddev->reconfig_mutex);
528 : : }
529 : :
530 : : /* Sometimes we need to take the lock in a situation where
531 : : * failure due to interrupts is not acceptable.
532 : : */
533 : 0 : static inline void mddev_lock_nointr(struct mddev *mddev)
534 : : {
535 : 0 : mutex_lock(&mddev->reconfig_mutex);
536 : 0 : }
537 : :
538 : 0 : static inline int mddev_trylock(struct mddev *mddev)
539 : : {
540 : 0 : return mutex_trylock(&mddev->reconfig_mutex);
541 : : }
542 : : extern void mddev_unlock(struct mddev *mddev);
543 : :
544 : : static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
545 : : {
546 : : atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
547 : : }
548 : :
549 : : static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
550 : : {
551 : : atomic_add(nr_sectors, &bio->bi_disk->sync_io);
552 : : }
553 : :
554 : : struct md_personality
555 : : {
556 : : char *name;
557 : : int level;
558 : : struct list_head list;
559 : : struct module *owner;
560 : : bool __must_check (*make_request)(struct mddev *mddev, struct bio *bio);
561 : : /*
562 : : * start up works that do NOT require md_thread. tasks that
563 : : * requires md_thread should go into start()
564 : : */
565 : : int (*run)(struct mddev *mddev);
566 : : /* start up works that require md threads */
567 : : int (*start)(struct mddev *mddev);
568 : : void (*free)(struct mddev *mddev, void *priv);
569 : : void (*status)(struct seq_file *seq, struct mddev *mddev);
570 : : /* error_handler must set ->faulty and clear ->in_sync
571 : : * if appropriate, and should abort recovery if needed
572 : : */
573 : : void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
574 : : int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
575 : : int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
576 : : int (*spare_active) (struct mddev *mddev);
577 : : sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped);
578 : : int (*resize) (struct mddev *mddev, sector_t sectors);
579 : : sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks);
580 : : int (*check_reshape) (struct mddev *mddev);
581 : : int (*start_reshape) (struct mddev *mddev);
582 : : void (*finish_reshape) (struct mddev *mddev);
583 : : void (*update_reshape_pos) (struct mddev *mddev);
584 : : /* quiesce suspends or resumes internal processing.
585 : : * 1 - stop new actions and wait for action io to complete
586 : : * 0 - return to normal behaviour
587 : : */
588 : : void (*quiesce) (struct mddev *mddev, int quiesce);
589 : : /* takeover is used to transition an array from one
590 : : * personality to another. The new personality must be able
591 : : * to handle the data in the current layout.
592 : : * e.g. 2drive raid1 -> 2drive raid5
593 : : * ndrive raid5 -> degraded n+1drive raid6 with special layout
594 : : * If the takeover succeeds, a new 'private' structure is returned.
595 : : * This needs to be installed and then ->run used to activate the
596 : : * array.
597 : : */
598 : : void *(*takeover) (struct mddev *mddev);
599 : : /* congested implements bdi.congested_fn().
600 : : * Will not be called while array is 'suspended' */
601 : : int (*congested)(struct mddev *mddev, int bits);
602 : : /* Changes the consistency policy of an active array. */
603 : : int (*change_consistency_policy)(struct mddev *mddev, const char *buf);
604 : : };
605 : :
606 : : struct md_sysfs_entry {
607 : : struct attribute attr;
608 : : ssize_t (*show)(struct mddev *, char *);
609 : : ssize_t (*store)(struct mddev *, const char *, size_t);
610 : : };
611 : : extern struct attribute_group md_bitmap_group;
612 : :
613 : 78 : static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name)
614 : : {
615 [ - - + - : 78 : if (sd)
- - ]
616 : 78 : return sysfs_get_dirent(sd, name);
617 : : return sd;
618 : : }
619 : 0 : static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd)
620 : : {
621 [ # # # # : 0 : if (sd)
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622 : 0 : sysfs_notify_dirent(sd);
623 : 0 : }
624 : :
625 : 0 : static inline char * mdname (struct mddev * mddev)
626 : : {
627 [ # # # # : 0 : return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
# # # # #
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# # ]
628 : : }
629 : :
630 : 0 : static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev)
631 : : {
632 : 0 : char nm[20];
633 [ # # # # ]: 0 : if (!test_bit(Replacement, &rdev->flags) &&
634 : 0 : !test_bit(Journal, &rdev->flags) &&
635 [ # # ]: 0 : mddev->kobj.sd) {
636 : 0 : sprintf(nm, "rd%d", rdev->raid_disk);
637 : 0 : return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
638 : : } else
639 : 0 : return 0;
640 : : }
641 : :
642 : 0 : static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev)
643 : : {
644 : 0 : char nm[20];
645 [ # # # # ]: 0 : if (!test_bit(Replacement, &rdev->flags) &&
646 : 0 : !test_bit(Journal, &rdev->flags) &&
647 [ # # ]: 0 : mddev->kobj.sd) {
648 : 0 : sprintf(nm, "rd%d", rdev->raid_disk);
649 : 0 : sysfs_remove_link(&mddev->kobj, nm);
650 : : }
651 : 0 : }
652 : :
653 : : /*
654 : : * iterates through some rdev ringlist. It's safe to remove the
655 : : * current 'rdev'. Dont touch 'tmp' though.
656 : : */
657 : : #define rdev_for_each_list(rdev, tmp, head) \
658 : : list_for_each_entry_safe(rdev, tmp, head, same_set)
659 : :
660 : : /*
661 : : * iterates through the 'same array disks' ringlist
662 : : */
663 : : #define rdev_for_each(rdev, mddev) \
664 : : list_for_each_entry(rdev, &((mddev)->disks), same_set)
665 : :
666 : : #define rdev_for_each_safe(rdev, tmp, mddev) \
667 : : list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set)
668 : :
669 : : #define rdev_for_each_rcu(rdev, mddev) \
670 : : list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set)
671 : :
672 : : struct md_thread {
673 : : void (*run) (struct md_thread *thread);
674 : : struct mddev *mddev;
675 : : wait_queue_head_t wqueue;
676 : : unsigned long flags;
677 : : struct task_struct *tsk;
678 : : unsigned long timeout;
679 : : void *private;
680 : : };
681 : :
682 : : #define THREAD_WAKEUP 0
683 : :
684 : : static inline void safe_put_page(struct page *p)
685 : : {
686 : : if (p) put_page(p);
687 : : }
688 : :
689 : : extern int register_md_personality(struct md_personality *p);
690 : : extern int unregister_md_personality(struct md_personality *p);
691 : : extern int register_md_cluster_operations(struct md_cluster_operations *ops,
692 : : struct module *module);
693 : : extern int unregister_md_cluster_operations(void);
694 : : extern int md_setup_cluster(struct mddev *mddev, int nodes);
695 : : extern void md_cluster_stop(struct mddev *mddev);
696 : : extern struct md_thread *md_register_thread(
697 : : void (*run)(struct md_thread *thread),
698 : : struct mddev *mddev,
699 : : const char *name);
700 : : extern void md_unregister_thread(struct md_thread **threadp);
701 : : extern void md_wakeup_thread(struct md_thread *thread);
702 : : extern void md_check_recovery(struct mddev *mddev);
703 : : extern void md_reap_sync_thread(struct mddev *mddev);
704 : : extern int mddev_init_writes_pending(struct mddev *mddev);
705 : : extern bool md_write_start(struct mddev *mddev, struct bio *bi);
706 : : extern void md_write_inc(struct mddev *mddev, struct bio *bi);
707 : : extern void md_write_end(struct mddev *mddev);
708 : : extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
709 : : extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
710 : : extern void md_finish_reshape(struct mddev *mddev);
711 : :
712 : : extern int mddev_congested(struct mddev *mddev, int bits);
713 : : extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);
714 : : extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
715 : : sector_t sector, int size, struct page *page);
716 : : extern int md_super_wait(struct mddev *mddev);
717 : : extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
718 : : struct page *page, int op, int op_flags,
719 : : bool metadata_op);
720 : : extern void md_do_sync(struct md_thread *thread);
721 : : extern void md_new_event(struct mddev *mddev);
722 : : extern void md_allow_write(struct mddev *mddev);
723 : : extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);
724 : : extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);
725 : : extern int md_check_no_bitmap(struct mddev *mddev);
726 : : extern int md_integrity_register(struct mddev *mddev);
727 : : extern int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev);
728 : : extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
729 : :
730 : : extern void mddev_init(struct mddev *mddev);
731 : : extern int md_run(struct mddev *mddev);
732 : : extern int md_start(struct mddev *mddev);
733 : : extern void md_stop(struct mddev *mddev);
734 : : extern void md_stop_writes(struct mddev *mddev);
735 : : extern int md_rdev_init(struct md_rdev *rdev);
736 : : extern void md_rdev_clear(struct md_rdev *rdev);
737 : :
738 : : extern void md_handle_request(struct mddev *mddev, struct bio *bio);
739 : : extern void mddev_suspend(struct mddev *mddev);
740 : : extern void mddev_resume(struct mddev *mddev);
741 : : extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
742 : : struct mddev *mddev);
743 : :
744 : : extern void md_reload_sb(struct mddev *mddev, int raid_disk);
745 : : extern void md_update_sb(struct mddev *mddev, int force);
746 : : extern void md_kick_rdev_from_array(struct md_rdev * rdev);
747 : : extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev,
748 : : bool is_suspend);
749 : : extern void mddev_destroy_serial_pool(struct mddev *mddev, struct md_rdev *rdev,
750 : : bool is_suspend);
751 : : struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr);
752 : : struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev);
753 : :
754 : : static inline bool is_mddev_broken(struct md_rdev *rdev, const char *md_type)
755 : : {
756 : : int flags = rdev->bdev->bd_disk->flags;
757 : :
758 : : if (!(flags & GENHD_FL_UP)) {
759 : : if (!test_and_set_bit(MD_BROKEN, &rdev->mddev->flags))
760 : : pr_warn("md: %s: %s array has a missing/failed member\n",
761 : : mdname(rdev->mddev), md_type);
762 : : return true;
763 : : }
764 : : return false;
765 : : }
766 : :
767 : 0 : static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
768 : : {
769 : 0 : int faulty = test_bit(Faulty, &rdev->flags);
770 [ # # # # ]: 0 : if (atomic_dec_and_test(&rdev->nr_pending) && faulty) {
771 : 0 : set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
772 : 0 : md_wakeup_thread(mddev->thread);
773 : : }
774 : 0 : }
775 : :
776 : : extern struct md_cluster_operations *md_cluster_ops;
777 : 0 : static inline int mddev_is_clustered(struct mddev *mddev)
778 : : {
779 [ # # # # : 0 : return mddev->cluster_info && mddev->bitmap_info.nodes > 1;
# # # # #
# # # # #
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# # ]
780 : : }
781 : :
782 : : /* clear unsupported mddev_flags */
783 : : static inline void mddev_clear_unsupported_flags(struct mddev *mddev,
784 : : unsigned long unsupported_flags)
785 : : {
786 : : mddev->flags &= ~unsupported_flags;
787 : : }
788 : :
789 : : static inline void mddev_check_writesame(struct mddev *mddev, struct bio *bio)
790 : : {
791 : : if (bio_op(bio) == REQ_OP_WRITE_SAME &&
792 : : !bio->bi_disk->queue->limits.max_write_same_sectors)
793 : : mddev->queue->limits.max_write_same_sectors = 0;
794 : : }
795 : :
796 : : static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio)
797 : : {
798 : : if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
799 : : !bio->bi_disk->queue->limits.max_write_zeroes_sectors)
800 : : mddev->queue->limits.max_write_zeroes_sectors = 0;
801 : : }
802 : : #endif /* _MD_MD_H */
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