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|
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
md.h : kernel internal structure of the Linux MD driver
Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
*/
#ifndef _MD_MD_H
#define _MD_MD_H
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/badblocks.h>
#include <linux/kobject.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/timer.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include "md-cluster.h"
#define MaxSector (~(sector_t)0)
/*
* These flags should really be called "NO_RETRY" rather than
* "FAILFAST" because they don't make any promise about time lapse,
* only about the number of retries, which will be zero.
* REQ_FAILFAST_DRIVER is not included because
* Commit: 4a27446f3e39 ("[SCSI] modify scsi to handle new fail fast flags.")
* seems to suggest that the errors it avoids retrying should usually
* be retried.
*/
#define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT)
/*
* The struct embedded in rdev is used to serialize IO.
*/
struct serial_in_rdev {
struct rb_root_cached serial_rb;
spinlock_t serial_lock;
wait_queue_head_t serial_io_wait;
};
/*
* MD's 'extended' device
*/
struct md_rdev {
struct list_head same_set; /* RAID devices within the same set */
sector_t sectors; /* Device size (in 512bytes sectors) */
struct mddev *mddev; /* RAID array if running */
int last_events; /* IO event timestamp */
/*
* If meta_bdev is non-NULL, it means that a separate device is
* being used to store the metadata (superblock/bitmap) which
* would otherwise be contained on the same device as the data (bdev).
*/
struct block_device *meta_bdev;
struct block_device *bdev; /* block device handle */
struct page *sb_page, *bb_page;
int sb_loaded;
__u64 sb_events;
sector_t data_offset; /* start of data in array */
sector_t new_data_offset;/* only relevant while reshaping */
sector_t sb_start; /* offset of the super block (in 512byte sectors) */
int sb_size; /* bytes in the superblock */
int preferred_minor; /* autorun support */
struct kobject kobj;
/* A device can be in one of three states based on two flags:
* Not working: faulty==1 in_sync==0
* Fully working: faulty==0 in_sync==1
* Working, but not
* in sync with array
* faulty==0 in_sync==0
*
* It can never have faulty==1, in_sync==1
* This reduces the burden of testing multiple flags in many cases
*/
unsigned long flags; /* bit set of 'enum flag_bits' bits. */
wait_queue_head_t blocked_wait;
int desc_nr; /* descriptor index in the superblock */
int raid_disk; /* role of device in array */
int new_raid_disk; /* role that the device will have in
* the array after a level-change completes.
*/
int saved_raid_disk; /* role that device used to have in the
* array and could again if we did a partial
* resync from the bitmap
*/
union {
sector_t recovery_offset;/* If this device has been partially
* recovered, this is where we were
* up to.
*/
sector_t journal_tail; /* If this device is a journal device,
* this is the journal tail (journal
* recovery start point)
*/
};
atomic_t nr_pending; /* number of pending requests.
* only maintained for arrays that
* support hot removal
*/
atomic_t read_errors; /* number of consecutive read errors that
* we have tried to ignore.
*/
time64_t last_read_error; /* monotonic time since our
* last read error
*/
atomic_t corrected_errors; /* number of corrected read errors,
* for reporting to userspace and storing
* in superblock.
*/
struct serial_in_rdev *serial; /* used for raid1 io serialization */
struct kernfs_node *sysfs_state; /* handle for 'state'
* sysfs entry */
/* handle for 'unacknowledged_bad_blocks' sysfs dentry */
struct kernfs_node *sysfs_unack_badblocks;
/* handle for 'bad_blocks' sysfs dentry */
struct kernfs_node *sysfs_badblocks;
struct badblocks badblocks;
struct {
short offset; /* Offset from superblock to start of PPL.
* Not used by external metadata. */
unsigned int size; /* Size in sectors of the PPL space */
sector_t sector; /* First sector of the PPL space */
} ppl;
};
enum flag_bits {
Faulty, /* device is known to have a fault */
In_sync, /* device is in_sync with rest of array */
Bitmap_sync, /* ..actually, not quite In_sync. Need a
* bitmap-based recovery to get fully in sync.
* The bit is only meaningful before device
* has been passed to pers->hot_add_disk.
*/
WriteMostly, /* Avoid reading if at all possible */
AutoDetected, /* added by auto-detect */
Blocked, /* An error occurred but has not yet
* been acknowledged by the metadata
* handler, so don't allow writes
* until it is cleared */
WriteErrorSeen, /* A write error has been seen on this
* device
*/
FaultRecorded, /* Intermediate state for clearing
* Blocked. The Fault is/will-be
* recorded in the metadata, but that
* metadata hasn't been stored safely
* on disk yet.
*/
BlockedBadBlocks, /* A writer is blocked because they
* found an unacknowledged bad-block.
* This can safely be cleared at any
* time, and the writer will re-check.
* It may be set at any time, and at
* worst the writer will timeout and
* re-check. So setting it as
* accurately as possible is good, but
* not absolutely critical.
*/
WantReplacement, /* This device is a candidate to be
* hot-replaced, either because it has
* reported some faults, or because
* of explicit request.
*/
Replacement, /* This device is a replacement for
* a want_replacement device with same
* raid_disk number.
*/
Candidate, /* For clustered environments only:
* This device is seen locally but not
* by the whole cluster
*/
Journal, /* This device is used as journal for
* raid-5/6.
* Usually, this device should be faster
* than other devices in the array
*/
ClusterRemove,
RemoveSynchronized, /* synchronize_rcu() was called after
* this device was known to be faulty,
* so it is safe to remove without
* another synchronize_rcu() call.
*/
ExternalBbl, /* External metadata provides bad
* block management for a disk
*/
FailFast, /* Minimal retries should be attempted on
* this device, so use REQ_FAILFAST_DEV.
* Also don't try to repair failed reads.
* It is expects that no bad block log
* is present.
*/
LastDev, /* Seems to be the last working dev as
* it didn't fail, so don't use FailFast
* any more for metadata
*/
CollisionCheck, /*
* check if there is collision between raid1
* serial bios.
*/
Holder, /* rdev is used as holder while opening
* underlying disk exclusively.
*/
};
static inline int is_badblock(struct md_rdev *rdev, sector_t s, int sectors,
sector_t *first_bad, int *bad_sectors)
{
if (unlikely(rdev->badblocks.count)) {
int rv = badblocks_check(&rdev->badblocks, rdev->data_offset + s,
sectors,
first_bad, bad_sectors);
if (rv)
*first_bad -= rdev->data_offset;
return rv;
}
return 0;
}
extern int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
int is_new);
extern int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
int is_new);
struct md_cluster_info;
/**
* enum mddev_flags - md device flags.
* @MD_ARRAY_FIRST_USE: First use of array, needs initialization.
* @MD_CLOSING: If set, we are closing the array, do not open it then.
* @MD_JOURNAL_CLEAN: A raid with journal is already clean.
* @MD_HAS_JOURNAL: The raid array has journal feature set.
* @MD_CLUSTER_RESYNC_LOCKED: cluster raid only, which means node, already took
* resync lock, need to release the lock.
* @MD_FAILFAST_SUPPORTED: Using MD_FAILFAST on metadata writes is supported as
* calls to md_error() will never cause the array to
* become failed.
* @MD_HAS_PPL: The raid array has PPL feature set.
* @MD_HAS_MULTIPLE_PPLS: The raid array has multiple PPLs feature set.
* @MD_ALLOW_SB_UPDATE: md_check_recovery is allowed to update the metadata
* without taking reconfig_mutex.
* @MD_UPDATING_SB: md_check_recovery is updating the metadata without
* explicitly holding reconfig_mutex.
* @MD_NOT_READY: do_md_run() is active, so 'array_state', ust not report that
* array is ready yet.
* @MD_BROKEN: This is used to stop writes and mark array as failed.
* @MD_DELETED: This device is being deleted
*
* change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added
*/
enum mddev_flags {
MD_ARRAY_FIRST_USE,
MD_CLOSING,
MD_JOURNAL_CLEAN,
MD_HAS_JOURNAL,
MD_CLUSTER_RESYNC_LOCKED,
MD_FAILFAST_SUPPORTED,
MD_HAS_PPL,
MD_HAS_MULTIPLE_PPLS,
MD_ALLOW_SB_UPDATE,
MD_UPDATING_SB,
MD_NOT_READY,
MD_BROKEN,
MD_DELETED,
};
enum mddev_sb_flags {
MD_SB_CHANGE_DEVS, /* Some device status has changed */
MD_SB_CHANGE_CLEAN, /* transition to or from 'clean' */
MD_SB_CHANGE_PENDING, /* switch from 'clean' to 'active' in progress */
MD_SB_NEED_REWRITE, /* metadata write needs to be repeated */
};
#define NR_SERIAL_INFOS 8
/* record current range of serialize IOs */
struct serial_info {
struct rb_node node;
sector_t start; /* start sector of rb node */
sector_t last; /* end sector of rb node */
sector_t _subtree_last; /* highest sector in subtree of rb node */
};
/*
* mddev->curr_resync stores the current sector of the resync but
* also has some overloaded values.
*/
enum {
/* No resync in progress */
MD_RESYNC_NONE = 0,
/* Yielded to allow another conflicting resync to commence */
MD_RESYNC_YIELDED = 1,
/* Delayed to check that there is no conflict with another sync */
MD_RESYNC_DELAYED = 2,
/* Any value greater than or equal to this is in an active resync */
MD_RESYNC_ACTIVE = 3,
};
struct mddev {
void *private;
struct md_personality *pers;
dev_t unit;
int md_minor;
struct list_head disks;
unsigned long flags;
unsigned long sb_flags;
int suspended;
struct mutex suspend_mutex;
struct percpu_ref active_io;
int ro;
int sysfs_active; /* set when sysfs deletes
* are happening, so run/
* takeover/stop are not safe
*/
struct gendisk *gendisk;
struct kobject kobj;
int hold_active;
#define UNTIL_IOCTL 1
#define UNTIL_STOP 2
/* Superblock information */
int major_version,
minor_version,
patch_version;
int persistent;
int external; /* metadata is
* managed externally */
char metadata_type[17]; /* externally set*/
int chunk_sectors;
time64_t ctime, utime;
int level, layout;
char clevel[16];
int raid_disks;
int max_disks;
sector_t dev_sectors; /* used size of
* component devices */
sector_t array_sectors; /* exported array size */
int external_size; /* size managed
* externally */
__u64 events;
/* If the last 'event' was simply a clean->dirty transition, and
* we didn't write it to the spares, then it is safe and simple
* to just decrement the event count on a dirty->clean transition.
* So we record that possibility here.
*/
int can_decrease_events;
char uuid[16];
/* If the array is being reshaped, we need to record the
* new shape and an indication of where we are up to.
* This is written to the superblock.
* If reshape_position is MaxSector, then no reshape is happening (yet).
*/
sector_t reshape_position;
int delta_disks, new_level, new_layout;
int new_chunk_sectors;
int reshape_backwards;
struct md_thread __rcu *thread; /* management thread */
struct md_thread __rcu *sync_thread; /* doing resync or reconstruct */
/* 'last_sync_action' is initialized to "none". It is set when a
* sync operation (i.e "data-check", "requested-resync", "resync",
* "recovery", or "reshape") is started. It holds this value even
* when the sync thread is "frozen" (interrupted) or "idle" (stopped
* or finished). It is overwritten when a new sync operation is begun.
*/
char *last_sync_action;
sector_t curr_resync; /* last block scheduled */
/* As resync requests can complete out of order, we cannot easily track
* how much resync has been completed. So we occasionally pause until
* everything completes, then set curr_resync_completed to curr_resync.
* As such it may be well behind the real resync mark, but it is a value
* we are certain of.
*/
sector_t curr_resync_completed;
unsigned long resync_mark; /* a recent timestamp */
sector_t resync_mark_cnt;/* blocks written at resync_mark */
sector_t curr_mark_cnt; /* blocks scheduled now */
sector_t resync_max_sectors; /* may be set by personality */
atomic64_t resync_mismatches; /* count of sectors where
* parity/replica mismatch found
*/
/* allow user-space to request suspension of IO to regions of the array */
sector_t suspend_lo;
sector_t suspend_hi;
/* if zero, use the system-wide default */
int sync_speed_min;
int sync_speed_max;
/* resync even though the same disks are shared among md-devices */
int parallel_resync;
int ok_start_degraded;
unsigned long recovery;
/* If a RAID personality determines that recovery (of a particular
* device) will fail due to a read error on the source device, it
* takes a copy of this number and does not attempt recovery again
* until this number changes.
*/
int recovery_disabled;
int in_sync; /* know to not need resync */
/* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so
* that we are never stopping an array while it is open.
* 'reconfig_mutex' protects all other reconfiguration.
* These locks are separate due to conflicting interactions
* with disk->open_mutex.
* Lock ordering is:
* reconfig_mutex -> disk->open_mutex
* disk->open_mutex -> open_mutex: e.g. __blkdev_get -> md_open
*/
struct mutex open_mutex;
struct mutex reconfig_mutex;
atomic_t active; /* general refcount */
atomic_t openers; /* number of active opens */
int changed; /* True if we might need to
* reread partition info */
int degraded; /* whether md should consider
* adding a spare
*/
atomic_t recovery_active; /* blocks scheduled, but not written */
wait_queue_head_t recovery_wait;
sector_t recovery_cp;
sector_t resync_min; /* user requested sync
* starts here */
sector_t resync_max; /* resync should pause
* when it gets here */
struct kernfs_node *sysfs_state; /* handle for 'array_state'
* file in sysfs.
*/
struct kernfs_node *sysfs_action; /* handle for 'sync_action' */
struct kernfs_node *sysfs_completed; /*handle for 'sync_completed' */
struct kernfs_node *sysfs_degraded; /*handle for 'degraded' */
struct kernfs_node *sysfs_level; /*handle for 'level' */
/* used for delayed sysfs removal */
struct work_struct del_work;
/* used for register new sync thread */
struct work_struct sync_work;
/* "lock" protects:
* flush_bio transition from NULL to !NULL
* rdev superblocks, events
* clearing MD_CHANGE_*
* in_sync - and related safemode and MD_CHANGE changes
* pers (also protected by reconfig_mutex and pending IO).
* clearing ->bitmap
* clearing ->bitmap_info.file
* changing ->resync_{min,max}
* setting MD_RECOVERY_RUNNING (which interacts with resync_{min,max})
*/
spinlock_t lock;
wait_queue_head_t sb_wait; /* for waiting on superblock updates */
atomic_t pending_writes; /* number of active superblock writes */
unsigned int safemode; /* if set, update "clean" superblock
* when no writes pending.
*/
unsigned int safemode_delay;
struct timer_list safemode_timer;
struct percpu_ref writes_pending;
int sync_checkers; /* # of threads checking writes_pending */
struct request_queue *queue; /* for plugging ... */
struct bitmap *bitmap; /* the bitmap for the device */
struct {
struct file *file; /* the bitmap file */
loff_t offset; /* offset from superblock of
* start of bitmap. May be
* negative, but not '0'
* For external metadata, offset
* from start of device.
*/
unsigned long space; /* space available at this offset */
loff_t default_offset; /* this is the offset to use when
* hot-adding a bitmap. It should
* eventually be settable by sysfs.
*/
unsigned long default_space; /* space available at
* default offset */
struct mutex mutex;
unsigned long chunksize;
unsigned long daemon_sleep; /* how many jiffies between updates? */
unsigned long max_write_behind; /* write-behind mode */
int external;
int nodes; /* Maximum number of nodes in the cluster */
char cluster_name[64]; /* Name of the cluster */
} bitmap_info;
atomic_t max_corr_read_errors; /* max read retries */
struct list_head all_mddevs;
const struct attribute_group *to_remove;
struct bio_set bio_set;
struct bio_set sync_set; /* for sync operations like
* metadata and bitmap writes
*/
struct bio_set io_clone_set;
/* Generic flush handling.
* The last to finish preflush schedules a worker to submit
* the rest of the request (without the REQ_PREFLUSH flag).
*/
struct bio *flush_bio;
atomic_t flush_pending;
ktime_t start_flush, prev_flush_start; /* prev_flush_start is when the previous completed
* flush was started.
*/
struct work_struct flush_work;
struct work_struct event_work; /* used by dm to report failure event */
mempool_t *serial_info_pool;
void (*sync_super)(struct mddev *mddev, struct md_rdev *rdev);
struct md_cluster_info *cluster_info;
unsigned int good_device_nr; /* good device num within cluster raid */
unsigned int noio_flag; /* for memalloc scope API */
/*
* Temporarily store rdev that will be finally removed when
* reconfig_mutex is unlocked, protected by reconfig_mutex.
*/
struct list_head deleting;
/* Used to synchronize idle and frozen for action_store() */
struct mutex sync_mutex;
/* The sequence number for sync thread */
atomic_t sync_seq;
bool has_superblocks:1;
bool fail_last_dev:1;
bool serialize_policy:1;
};
enum recovery_flags {
/*
* If neither SYNC or RESHAPE are set, then it is a recovery.
*/
MD_RECOVERY_RUNNING, /* a thread is running, or about to be started */
MD_RECOVERY_SYNC, /* actually doing a resync, not a recovery */
MD_RECOVERY_RECOVER, /* doing recovery, or need to try it. */
MD_RECOVERY_INTR, /* resync needs to be aborted for some reason */
MD_RECOVERY_DONE, /* thread is done and is waiting to be reaped */
MD_RECOVERY_NEEDED, /* we might need to start a resync/recover */
MD_RECOVERY_REQUESTED, /* user-space has requested a sync (used with SYNC) */
MD_RECOVERY_CHECK, /* user-space request for check-only, no repair */
MD_RECOVERY_RESHAPE, /* A reshape is happening */
MD_RECOVERY_FROZEN, /* User request to abort, and not restart, any action */
MD_RECOVERY_ERROR, /* sync-action interrupted because io-error */
MD_RECOVERY_WAIT, /* waiting for pers->start() to finish */
MD_RESYNCING_REMOTE, /* remote node is running resync thread */
};
enum md_ro_state {
MD_RDWR,
MD_RDONLY,
MD_AUTO_READ,
MD_MAX_STATE
};
static inline bool md_is_rdwr(struct mddev *mddev)
{
return (mddev->ro == MD_RDWR);
}
static inline bool is_md_suspended(struct mddev *mddev)
{
return percpu_ref_is_dying(&mddev->active_io);
}
static inline int __must_check mddev_lock(struct mddev *mddev)
{
return mutex_lock_interruptible(&mddev->reconfig_mutex);
}
/* Sometimes we need to take the lock in a situation where
* failure due to interrupts is not acceptable.
*/
static inline void mddev_lock_nointr(struct mddev *mddev)
{
mutex_lock(&mddev->reconfig_mutex);
}
static inline int mddev_trylock(struct mddev *mddev)
{
return mutex_trylock(&mddev->reconfig_mutex);
}
extern void mddev_unlock(struct mddev *mddev);
static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
{
atomic_add(nr_sectors, &bdev->bd_disk->sync_io);
}
static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
{
md_sync_acct(bio->bi_bdev, nr_sectors);
}
struct md_personality
{
char *name;
int level;
struct list_head list;
struct module *owner;
bool __must_check (*make_request)(struct mddev *mddev, struct bio *bio);
/*
* start up works that do NOT require md_thread. tasks that
* requires md_thread should go into start()
*/
int (*run)(struct mddev *mddev);
/* start up works that require md threads */
int (*start)(struct mddev *mddev);
void (*free)(struct mddev *mddev, void *priv);
void (*status)(struct seq_file *seq, struct mddev *mddev);
/* error_handler must set ->faulty and clear ->in_sync
* if appropriate, and should abort recovery if needed
*/
void (*error_handler)(struct mddev *mddev, struct md_rdev *rdev);
int (*hot_add_disk) (struct mddev *mddev, struct md_rdev *rdev);
int (*hot_remove_disk) (struct mddev *mddev, struct md_rdev *rdev);
int (*spare_active) (struct mddev *mddev);
sector_t (*sync_request)(struct mddev *mddev, sector_t sector_nr, int *skipped);
int (*resize) (struct mddev *mddev, sector_t sectors);
sector_t (*size) (struct mddev *mddev, sector_t sectors, int raid_disks);
int (*check_reshape) (struct mddev *mddev);
int (*start_reshape) (struct mddev *mddev);
void (*finish_reshape) (struct mddev *mddev);
void (*update_reshape_pos) (struct mddev *mddev);
void (*prepare_suspend) (struct mddev *mddev);
/* quiesce suspends or resumes internal processing.
* 1 - stop new actions and wait for action io to complete
* 0 - return to normal behaviour
*/
void (*quiesce) (struct mddev *mddev, int quiesce);
/* takeover is used to transition an array from one
* personality to another. The new personality must be able
* to handle the data in the current layout.
* e.g. 2drive raid1 -> 2drive raid5
* ndrive raid5 -> degraded n+1drive raid6 with special layout
* If the takeover succeeds, a new 'private' structure is returned.
* This needs to be installed and then ->run used to activate the
* array.
*/
void *(*takeover) (struct mddev *mddev);
/* Changes the consistency policy of an active array. */
int (*change_consistency_policy)(struct mddev *mddev, const char *buf);
};
struct md_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct mddev *, char *);
ssize_t (*store)(struct mddev *, const char *, size_t);
};
extern const struct attribute_group md_bitmap_group;
static inline struct kernfs_node *sysfs_get_dirent_safe(struct kernfs_node *sd, char *name)
{
if (sd)
return sysfs_get_dirent(sd, name);
return sd;
}
static inline void sysfs_notify_dirent_safe(struct kernfs_node *sd)
{
if (sd)
sysfs_notify_dirent(sd);
}
static inline char * mdname (struct mddev * mddev)
{
return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
}
static inline int sysfs_link_rdev(struct mddev *mddev, struct md_rdev *rdev)
{
char nm[20];
if (!test_bit(Replacement, &rdev->flags) &&
!test_bit(Journal, &rdev->flags) &&
mddev->kobj.sd) {
sprintf(nm, "rd%d", rdev->raid_disk);
return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
} else
return 0;
}
static inline void sysfs_unlink_rdev(struct mddev *mddev, struct md_rdev *rdev)
{
char nm[20];
if (!test_bit(Replacement, &rdev->flags) &&
!test_bit(Journal, &rdev->flags) &&
mddev->kobj.sd) {
sprintf(nm, "rd%d", rdev->raid_disk);
sysfs_remove_link(&mddev->kobj, nm);
}
}
/*
* iterates through some rdev ringlist. It's safe to remove the
* current 'rdev'. Dont touch 'tmp' though.
*/
#define rdev_for_each_list(rdev, tmp, head) \
list_for_each_entry_safe(rdev, tmp, head, same_set)
/*
* iterates through the 'same array disks' ringlist
*/
#define rdev_for_each(rdev, mddev) \
list_for_each_entry(rdev, &((mddev)->disks), same_set)
#define rdev_for_each_safe(rdev, tmp, mddev) \
list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set)
#define rdev_for_each_rcu(rdev, mddev) \
list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set)
struct md_thread {
void (*run) (struct md_thread *thread);
struct mddev *mddev;
wait_queue_head_t wqueue;
unsigned long flags;
struct task_struct *tsk;
unsigned long timeout;
void *private;
};
struct md_io_clone {
struct mddev *mddev;
struct bio *orig_bio;
unsigned long start_time;
struct bio bio_clone;
};
#define THREAD_WAKEUP 0
static inline void safe_put_page(struct page *p)
{
if (p) put_page(p);
}
extern int register_md_personality(struct md_personality *p);
extern int unregister_md_personality(struct md_personality *p);
extern int register_md_cluster_operations(struct md_cluster_operations *ops,
struct module *module);
extern int unregister_md_cluster_operations(void);
extern int md_setup_cluster(struct mddev *mddev, int nodes);
extern void md_cluster_stop(struct mddev *mddev);
extern struct md_thread *md_register_thread(
void (*run)(struct md_thread *thread),
struct mddev *mddev,
const char *name);
extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp);
extern void md_wakeup_thread(struct md_thread __rcu *thread);
extern void md_check_recovery(struct mddev *mddev);
extern void md_reap_sync_thread(struct mddev *mddev);
extern bool md_write_start(struct mddev *mddev, struct bio *bi);
extern void md_write_inc(struct mddev *mddev, struct bio *bi);
extern void md_write_end(struct mddev *mddev);
extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
extern void md_finish_reshape(struct mddev *mddev);
void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
struct bio *bio, sector_t start, sector_t size);
void md_account_bio(struct mddev *mddev, struct bio **bio);
extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);
extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
sector_t sector, int size, struct page *page);
extern int md_super_wait(struct mddev *mddev);
extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
struct page *page, blk_opf_t opf, bool metadata_op);
extern void md_do_sync(struct md_thread *thread);
extern void md_new_event(void);
extern void md_allow_write(struct mddev *mddev);
extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev);
extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors);
extern int md_check_no_bitmap(struct mddev *mddev);
extern int md_integrity_register(struct mddev *mddev);
extern int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev);
extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
extern int mddev_init(struct mddev *mddev);
extern void mddev_destroy(struct mddev *mddev);
struct mddev *md_alloc(dev_t dev, char *name);
void mddev_put(struct mddev *mddev);
extern int md_run(struct mddev *mddev);
extern int md_start(struct mddev *mddev);
extern void md_stop(struct mddev *mddev);
extern void md_stop_writes(struct mddev *mddev);
extern int md_rdev_init(struct md_rdev *rdev);
extern void md_rdev_clear(struct md_rdev *rdev);
extern void md_handle_request(struct mddev *mddev, struct bio *bio);
extern void mddev_suspend(struct mddev *mddev);
extern void mddev_resume(struct mddev *mddev);
extern int __mddev_suspend(struct mddev *mddev, bool interruptible);
extern void __mddev_resume(struct mddev *mddev);
extern void md_reload_sb(struct mddev *mddev, int raid_disk);
extern void md_update_sb(struct mddev *mddev, int force);
extern void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev,
bool is_suspend);
extern void mddev_destroy_serial_pool(struct mddev *mddev, struct md_rdev *rdev,
bool is_suspend);
struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr);
struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev);
static inline bool is_rdev_broken(struct md_rdev *rdev)
{
return !disk_live(rdev->bdev->bd_disk);
}
static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
{
int faulty = test_bit(Faulty, &rdev->flags);
if (atomic_dec_and_test(&rdev->nr_pending) && faulty) {
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
}
}
extern struct md_cluster_operations *md_cluster_ops;
static inline int mddev_is_clustered(struct mddev *mddev)
{
return mddev->cluster_info && mddev->bitmap_info.nodes > 1;
}
/* clear unsupported mddev_flags */
static inline void mddev_clear_unsupported_flags(struct mddev *mddev,
unsigned long unsupported_flags)
{
mddev->flags &= ~unsupported_flags;
}
static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio)
{
if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
!bio->bi_bdev->bd_disk->queue->limits.max_write_zeroes_sectors)
mddev->queue->limits.max_write_zeroes_sectors = 0;
}
static inline int mddev_suspend_and_lock(struct mddev *mddev)
{
int ret;
ret = __mddev_suspend(mddev, true);
if (ret)
return ret;
ret = mddev_lock(mddev);
if (ret)
__mddev_resume(mddev);
return ret;
}
static inline void mddev_suspend_and_lock_nointr(struct mddev *mddev)
{
__mddev_suspend(mddev, false);
mutex_lock(&mddev->reconfig_mutex);
}
static inline void mddev_unlock_and_resume(struct mddev *mddev)
{
mddev_unlock(mddev);
__mddev_resume(mddev);
}
struct mdu_array_info_s;
struct mdu_disk_info_s;
extern int mdp_major;
extern struct workqueue_struct *md_bitmap_wq;
void md_autostart_arrays(int part);
int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
int do_md_run(struct mddev *mddev);
extern const struct block_device_operations md_fops;
#endif /* _MD_MD_H */
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