36fad858a7
There are places where sysfs links to rdev are handled in a same way. Add the helper functions to consolidate them. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
531 lines
17 KiB
C
531 lines
17 KiB
C
/*
|
|
md_k.h : kernel internal structure of the Linux MD driver
|
|
Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
(for example /usr/src/linux/COPYING); if not, write to the Free
|
|
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
|
|
#ifndef _MD_MD_H
|
|
#define _MD_MD_H
|
|
|
|
#include <linux/blkdev.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>
|
|
|
|
#define MaxSector (~(sector_t)0)
|
|
|
|
typedef struct mddev_s mddev_t;
|
|
typedef struct mdk_rdev_s mdk_rdev_t;
|
|
|
|
/*
|
|
* MD's 'extended' device
|
|
*/
|
|
struct mdk_rdev_s
|
|
{
|
|
struct list_head same_set; /* RAID devices within the same set */
|
|
|
|
sector_t sectors; /* Device size (in 512bytes sectors) */
|
|
mddev_t *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;
|
|
int sb_loaded;
|
|
__u64 sb_events;
|
|
sector_t data_offset; /* start of data in array */
|
|
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;
|
|
#define Faulty 1 /* device is known to have a fault */
|
|
#define In_sync 2 /* device is in_sync with rest of array */
|
|
#define WriteMostly 4 /* Avoid reading if at all possible */
|
|
#define AutoDetected 7 /* added by auto-detect */
|
|
#define Blocked 8 /* An error occurred on an externally
|
|
* managed array, don't allow writes
|
|
* until it is cleared */
|
|
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
|
|
*/
|
|
sector_t recovery_offset;/* If this device has been partially
|
|
* recovered, this is where we were
|
|
* up to.
|
|
*/
|
|
|
|
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.
|
|
*/
|
|
struct timespec 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 work_struct del_work; /* used for delayed sysfs removal */
|
|
|
|
struct sysfs_dirent *sysfs_state; /* handle for 'state'
|
|
* sysfs entry */
|
|
};
|
|
|
|
struct mddev_s
|
|
{
|
|
void *private;
|
|
struct mdk_personality *pers;
|
|
dev_t unit;
|
|
int md_minor;
|
|
struct list_head disks;
|
|
unsigned long flags;
|
|
#define MD_CHANGE_DEVS 0 /* Some device status has changed */
|
|
#define MD_CHANGE_CLEAN 1 /* transition to or from 'clean' */
|
|
#define MD_CHANGE_PENDING 2 /* switch from 'clean' to 'active' in progress */
|
|
#define MD_ARRAY_FIRST_USE 3 /* First use of array, needs initialization */
|
|
|
|
int suspended;
|
|
atomic_t active_io;
|
|
int ro;
|
|
int sysfs_active; /* set when sysfs deletes
|
|
* are happening, so run/
|
|
* takeover/stop are not safe
|
|
*/
|
|
int ready; /* See when safe to pass
|
|
* IO requests down */
|
|
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;
|
|
time_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;
|
|
|
|
atomic_t plug_cnt; /* If device is expecting
|
|
* more bios soon.
|
|
*/
|
|
struct mdk_thread_s *thread; /* management thread */
|
|
struct mdk_thread_s *sync_thread; /* doing resync or reconstruct */
|
|
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 */
|
|
|
|
sector_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;
|
|
/* recovery/resync flags
|
|
* NEEDED: we might need to start a resync/recover
|
|
* RUNNING: a thread is running, or about to be started
|
|
* SYNC: actually doing a resync, not a recovery
|
|
* RECOVER: doing recovery, or need to try it.
|
|
* INTR: resync needs to be aborted for some reason
|
|
* DONE: thread is done and is waiting to be reaped
|
|
* REQUEST: user-space has requested a sync (used with SYNC)
|
|
* CHECK: user-space request for check-only, no repair
|
|
* RESHAPE: A reshape is happening
|
|
*
|
|
* If neither SYNC or RESHAPE are set, then it is a recovery.
|
|
*/
|
|
#define MD_RECOVERY_RUNNING 0
|
|
#define MD_RECOVERY_SYNC 1
|
|
#define MD_RECOVERY_RECOVER 2
|
|
#define MD_RECOVERY_INTR 3
|
|
#define MD_RECOVERY_DONE 4
|
|
#define MD_RECOVERY_NEEDED 5
|
|
#define MD_RECOVERY_REQUESTED 6
|
|
#define MD_RECOVERY_CHECK 7
|
|
#define MD_RECOVERY_RESHAPE 8
|
|
#define MD_RECOVERY_FROZEN 9
|
|
|
|
unsigned long recovery;
|
|
int recovery_disabled; /* if we detect that recovery
|
|
* will always fail, set this
|
|
* so we don't loop trying */
|
|
|
|
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 bdev->bd_mutex.
|
|
* Lock ordering is:
|
|
* reconfig_mutex -> bd_mutex : e.g. do_md_run -> revalidate_disk
|
|
* bd_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 sysfs_dirent *sysfs_state; /* handle for 'array_state'
|
|
* file in sysfs.
|
|
*/
|
|
struct sysfs_dirent *sysfs_action; /* handle for 'sync_action' */
|
|
|
|
struct work_struct del_work; /* used for delayed sysfs removal */
|
|
|
|
spinlock_t write_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;
|
|
atomic_t 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.
|
|
*/
|
|
loff_t default_offset; /* this is the offset to use when
|
|
* hot-adding a bitmap. It should
|
|
* eventually be settable by sysfs.
|
|
*/
|
|
/* When md is serving under dm, it might use a
|
|
* dirty_log to store the bits.
|
|
*/
|
|
struct dm_dirty_log *log;
|
|
|
|
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;
|
|
} bitmap_info;
|
|
|
|
atomic_t max_corr_read_errors; /* max read retries */
|
|
struct list_head all_mddevs;
|
|
|
|
struct attribute_group *to_remove;
|
|
|
|
struct bio_set *bio_set;
|
|
|
|
/* Generic flush handling.
|
|
* The last to finish preflush schedules a worker to submit
|
|
* the rest of the request (without the REQ_FLUSH flag).
|
|
*/
|
|
struct bio *flush_bio;
|
|
atomic_t flush_pending;
|
|
struct work_struct flush_work;
|
|
struct work_struct event_work; /* used by dm to report failure event */
|
|
void (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
|
|
};
|
|
|
|
|
|
static inline void rdev_dec_pending(mdk_rdev_t *rdev, mddev_t *mddev)
|
|
{
|
|
int faulty = test_bit(Faulty, &rdev->flags);
|
|
if (atomic_dec_and_test(&rdev->nr_pending) && faulty)
|
|
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
|
|
}
|
|
|
|
static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
|
|
{
|
|
atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
|
|
}
|
|
|
|
struct mdk_personality
|
|
{
|
|
char *name;
|
|
int level;
|
|
struct list_head list;
|
|
struct module *owner;
|
|
int (*make_request)(mddev_t *mddev, struct bio *bio);
|
|
int (*run)(mddev_t *mddev);
|
|
int (*stop)(mddev_t *mddev);
|
|
void (*status)(struct seq_file *seq, mddev_t *mddev);
|
|
/* error_handler must set ->faulty and clear ->in_sync
|
|
* if appropriate, and should abort recovery if needed
|
|
*/
|
|
void (*error_handler)(mddev_t *mddev, mdk_rdev_t *rdev);
|
|
int (*hot_add_disk) (mddev_t *mddev, mdk_rdev_t *rdev);
|
|
int (*hot_remove_disk) (mddev_t *mddev, int number);
|
|
int (*spare_active) (mddev_t *mddev);
|
|
sector_t (*sync_request)(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster);
|
|
int (*resize) (mddev_t *mddev, sector_t sectors);
|
|
sector_t (*size) (mddev_t *mddev, sector_t sectors, int raid_disks);
|
|
int (*check_reshape) (mddev_t *mddev);
|
|
int (*start_reshape) (mddev_t *mddev);
|
|
void (*finish_reshape) (mddev_t *mddev);
|
|
/* quiesce moves between quiescence states
|
|
* 0 - fully active
|
|
* 1 - no new requests allowed
|
|
* others - reserved
|
|
*/
|
|
void (*quiesce) (mddev_t *mddev, int state);
|
|
/* 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) (mddev_t *mddev);
|
|
};
|
|
|
|
|
|
struct md_sysfs_entry {
|
|
struct attribute attr;
|
|
ssize_t (*show)(mddev_t *, char *);
|
|
ssize_t (*store)(mddev_t *, const char *, size_t);
|
|
};
|
|
extern struct attribute_group md_bitmap_group;
|
|
|
|
static inline struct sysfs_dirent *sysfs_get_dirent_safe(struct sysfs_dirent *sd, char *name)
|
|
{
|
|
if (sd)
|
|
return sysfs_get_dirent(sd, NULL, name);
|
|
return sd;
|
|
}
|
|
static inline void sysfs_notify_dirent_safe(struct sysfs_dirent *sd)
|
|
{
|
|
if (sd)
|
|
sysfs_notify_dirent(sd);
|
|
}
|
|
|
|
static inline char * mdname (mddev_t * mddev)
|
|
{
|
|
return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
|
|
}
|
|
|
|
static inline int sysfs_link_rdev(mddev_t *mddev, mdk_rdev_t *rdev)
|
|
{
|
|
char nm[20];
|
|
sprintf(nm, "rd%d", rdev->raid_disk);
|
|
return sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
|
|
}
|
|
|
|
static inline void sysfs_unlink_rdev(mddev_t *mddev, mdk_rdev_t *rdev)
|
|
{
|
|
char nm[20];
|
|
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, 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)
|
|
|
|
typedef struct mdk_thread_s {
|
|
void (*run) (mddev_t *mddev);
|
|
mddev_t *mddev;
|
|
wait_queue_head_t wqueue;
|
|
unsigned long flags;
|
|
struct task_struct *tsk;
|
|
unsigned long timeout;
|
|
} mdk_thread_t;
|
|
|
|
#define THREAD_WAKEUP 0
|
|
|
|
#define __wait_event_lock_irq(wq, condition, lock, cmd) \
|
|
do { \
|
|
wait_queue_t __wait; \
|
|
init_waitqueue_entry(&__wait, current); \
|
|
\
|
|
add_wait_queue(&wq, &__wait); \
|
|
for (;;) { \
|
|
set_current_state(TASK_UNINTERRUPTIBLE); \
|
|
if (condition) \
|
|
break; \
|
|
spin_unlock_irq(&lock); \
|
|
cmd; \
|
|
schedule(); \
|
|
spin_lock_irq(&lock); \
|
|
} \
|
|
current->state = TASK_RUNNING; \
|
|
remove_wait_queue(&wq, &__wait); \
|
|
} while (0)
|
|
|
|
#define wait_event_lock_irq(wq, condition, lock, cmd) \
|
|
do { \
|
|
if (condition) \
|
|
break; \
|
|
__wait_event_lock_irq(wq, condition, lock, cmd); \
|
|
} while (0)
|
|
|
|
static inline void safe_put_page(struct page *p)
|
|
{
|
|
if (p) put_page(p);
|
|
}
|
|
|
|
extern int register_md_personality(struct mdk_personality *p);
|
|
extern int unregister_md_personality(struct mdk_personality *p);
|
|
extern mdk_thread_t * md_register_thread(void (*run) (mddev_t *mddev),
|
|
mddev_t *mddev, const char *name);
|
|
extern void md_unregister_thread(mdk_thread_t *thread);
|
|
extern void md_wakeup_thread(mdk_thread_t *thread);
|
|
extern void md_check_recovery(mddev_t *mddev);
|
|
extern void md_write_start(mddev_t *mddev, struct bio *bi);
|
|
extern void md_write_end(mddev_t *mddev);
|
|
extern void md_done_sync(mddev_t *mddev, int blocks, int ok);
|
|
extern void md_error(mddev_t *mddev, mdk_rdev_t *rdev);
|
|
|
|
extern int mddev_congested(mddev_t *mddev, int bits);
|
|
extern void md_flush_request(mddev_t *mddev, struct bio *bio);
|
|
extern void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
|
|
sector_t sector, int size, struct page *page);
|
|
extern void md_super_wait(mddev_t *mddev);
|
|
extern int sync_page_io(mdk_rdev_t *rdev, sector_t sector, int size,
|
|
struct page *page, int rw, bool metadata_op);
|
|
extern void md_do_sync(mddev_t *mddev);
|
|
extern void md_new_event(mddev_t *mddev);
|
|
extern int md_allow_write(mddev_t *mddev);
|
|
extern void md_wait_for_blocked_rdev(mdk_rdev_t *rdev, mddev_t *mddev);
|
|
extern void md_set_array_sectors(mddev_t *mddev, sector_t array_sectors);
|
|
extern int md_check_no_bitmap(mddev_t *mddev);
|
|
extern int md_integrity_register(mddev_t *mddev);
|
|
extern void md_integrity_add_rdev(mdk_rdev_t *rdev, mddev_t *mddev);
|
|
extern int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale);
|
|
extern void restore_bitmap_write_access(struct file *file);
|
|
|
|
extern void mddev_init(mddev_t *mddev);
|
|
extern int md_run(mddev_t *mddev);
|
|
extern void md_stop(mddev_t *mddev);
|
|
extern void md_stop_writes(mddev_t *mddev);
|
|
extern void md_rdev_init(mdk_rdev_t *rdev);
|
|
|
|
extern void mddev_suspend(mddev_t *mddev);
|
|
extern void mddev_resume(mddev_t *mddev);
|
|
extern struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
|
|
mddev_t *mddev);
|
|
extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
|
|
mddev_t *mddev);
|
|
extern int mddev_check_plugged(mddev_t *mddev);
|
|
#endif /* _MD_MD_H */
|