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/*
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_K_H
#define _MD_K_H
#define MD_RESERVED 0UL
#define LINEAR 1UL
#define RAID0 2UL
#define RAID1 3UL
#define RAID5 4UL
#define TRANSLUCENT 5UL
#define HSM 6UL
#define MULTIPATH 7UL
#define MAX_PERSONALITY 8UL
#define LEVEL_MULTIPATH (-4)
#define LEVEL_LINEAR (-1)
#define MaxSector (~(sector_t)0)
#define MD_THREAD_NAME_MAX 14
static inline int pers_to_level (int pers)
{
switch (pers) {
case MULTIPATH: return LEVEL_MULTIPATH;
case HSM: return -3;
case TRANSLUCENT: return -2;
case LINEAR: return LEVEL_LINEAR;
case RAID0: return 0;
case RAID1: return 1;
case RAID5: return 5;
}
BUG();
return MD_RESERVED;
}
static inline int level_to_pers (int level)
{
switch (level) {
case LEVEL_MULTIPATH: return MULTIPATH;
case -3: return HSM;
case -2: return TRANSLUCENT;
case LEVEL_LINEAR: return LINEAR;
case 0: return RAID0;
case 1: return RAID1;
case 4:
case 5: return RAID5;
}
return MD_RESERVED;
}
typedef struct mddev_s mddev_t;
typedef struct mdk_rdev_s mdk_rdev_t;
#define MAX_MD_DEVS 256 /* Max number of md dev */
/*
* options passed in raidrun:
*/
#define MAX_CHUNK_SIZE (4096*1024)
/*
* default readahead
*/
static inline int disk_faulty(mdp_disk_t * d)
{
return d->state & (1 << MD_DISK_FAULTY);
}
static inline int disk_active(mdp_disk_t * d)
{
return d->state & (1 << MD_DISK_ACTIVE);
}
static inline int disk_sync(mdp_disk_t * d)
{
return d->state & (1 << MD_DISK_SYNC);
}
static inline int disk_spare(mdp_disk_t * d)
{
return !disk_sync(d) && !disk_active(d) && !disk_faulty(d);
}
static inline int disk_removed(mdp_disk_t * d)
{
return d->state & (1 << MD_DISK_REMOVED);
}
static inline void mark_disk_faulty(mdp_disk_t * d)
{
d->state |= (1 << MD_DISK_FAULTY);
}
static inline void mark_disk_active(mdp_disk_t * d)
{
d->state |= (1 << MD_DISK_ACTIVE);
}
static inline void mark_disk_sync(mdp_disk_t * d)
{
d->state |= (1 << MD_DISK_SYNC);
}
static inline void mark_disk_spare(mdp_disk_t * d)
{
d->state = 0;
}
static inline void mark_disk_removed(mdp_disk_t * d)
{
d->state = (1 << MD_DISK_FAULTY) | (1 << MD_DISK_REMOVED);
}
static inline void mark_disk_inactive(mdp_disk_t * d)
{
d->state &= ~(1 << MD_DISK_ACTIVE);
}
static inline void mark_disk_nonsync(mdp_disk_t * d)
{
d->state &= ~(1 << MD_DISK_SYNC);
}
/*
* MD's 'extended' device
*/
struct mdk_rdev_s
{
struct list_head same_set; /* RAID devices within the same set */
sector_t size; /* Device size (in blocks) */
mddev_t *mddev; /* RAID array if running */
unsigned long last_events; /* IO event timestamp */
struct block_device *bdev; /* block device handle */
struct page *sb_page;
int sb_loaded;
sector_t data_offset; /* start of data in array */
sector_t sb_offset;
int preferred_minor; /* autorun support */
/* 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
*/
int faulty; /* if faulty do not issue IO requests */
int in_sync; /* device is a full member of the array */
int desc_nr; /* descriptor index in the superblock */
int raid_disk; /* role of device in array */
atomic_t nr_pending; /* number of pending requests.
* only maintained for arrays that
* support hot removal
*/
};
typedef struct mdk_personality_s mdk_personality_t;
struct mddev_s
{
void *private;
mdk_personality_t *pers;
int __minor;
struct list_head disks;
int sb_dirty;
int ro;
/* Superblock information */
int major_version,
minor_version,
patch_version;
int persistent;
int chunk_size;
time_t ctime, utime;
int level, layout;
int raid_disks;
int max_disks;
sector_t size; /* used size of component devices */
sector_t array_size; /* exported array size */
__u64 events;
char uuid[16];
struct mdk_thread_s *thread; /* management thread */
struct mdk_thread_s *sync_thread; /* doing resync or reconstruct */
unsigned long curr_resync; /* blocks scheduled */
unsigned long resync_mark; /* a recent timestamp */
unsigned long resync_mark_cnt;/* blocks written at resync_mark */
/* 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
* ERR: and IO error was detected - abort the resync/recovery
* INTR: someone requested a (clean) early abort.
* DONE: thread is done and is waiting to be reaped
*/
#define MD_RECOVERY_RUNNING 0
#define MD_RECOVERY_SYNC 1
#define MD_RECOVERY_ERR 2
#define MD_RECOVERY_INTR 3
#define MD_RECOVERY_DONE 4
#define MD_RECOVERY_NEEDED 5
unsigned long recovery;
int in_sync; /* know to not need resync */
struct semaphore reconfig_sem;
atomic_t active;
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;
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;
request_queue_t *queue; /* for plugging ... */
struct list_head all_mddevs;
};
struct mdk_personality_s
{
char *name;
struct module *owner;
int (*make_request)(request_queue_t *q, 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);
int (*sync_request)(mddev_t *mddev, sector_t sector_nr, int go_faster);
};
/*
* Currently we index md_array directly, based on the minor
* number. This will have to change to dynamic allocation
* once we start supporting partitioning of md devices.
*/
static inline int mdidx (mddev_t * mddev)
{
return mddev->__minor;
}
extern mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr);
/*
* iterates through some rdev ringlist. It's safe to remove the
* current 'rdev'. Dont touch 'tmp' though.
*/
#define ITERATE_RDEV_GENERIC(head,rdev,tmp) \
\
for ((tmp) = (head).next; \
(rdev) = (list_entry((tmp), mdk_rdev_t, same_set)), \
(tmp) = (tmp)->next, (tmp)->prev != &(head) \
; )
/*
* iterates through the 'same array disks' ringlist
*/
#define ITERATE_RDEV(mddev,rdev,tmp) \
ITERATE_RDEV_GENERIC((mddev)->disks,rdev,tmp)
/*
* Iterates through 'pending RAID disks'
*/
#define ITERATE_RDEV_PENDING(rdev,tmp) \
ITERATE_RDEV_GENERIC(pending_raid_disks,rdev,tmp)
typedef struct mdk_thread_s {
void (*run) (mddev_t *mddev);
mddev_t *mddev;
wait_queue_head_t wqueue;
unsigned long flags;
struct completion *event;
struct task_struct *tsk;
const char *name;
} mdk_thread_t;
#define THREAD_WAKEUP 0
#define __wait_event_lock_irq(wq, condition, lock) \
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); \
blk_run_queues(); \
schedule(); \
spin_lock_irq(&lock); \
} \
current->state = TASK_RUNNING; \
remove_wait_queue(&wq, &__wait); \
} while (0)
#define wait_event_lock_irq(wq, condition, lock) \
do { \
if (condition) \
break; \
__wait_event_lock_irq(wq, condition, lock); \
} while (0)
#define __wait_disk_event(wq, condition) \
do { \
wait_queue_t __wait; \
init_waitqueue_entry(&__wait, current); \
\
add_wait_queue(&wq, &__wait); \
for (;;) { \
set_current_state(TASK_UNINTERRUPTIBLE); \
if (condition) \
break; \
blk_run_queues(); \
schedule(); \
} \
current->state = TASK_RUNNING; \
remove_wait_queue(&wq, &__wait); \
} while (0)
#define wait_disk_event(wq, condition) \
do { \
if (condition) \
break; \
__wait_disk_event(wq, condition); \
} while (0)
#endif