diff options
Diffstat (limited to 'include/linux/raid/md_k.h')
| -rw-r--r-- | include/linux/raid/md_k.h | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h new file mode 100644 index 000000000000..c9a0d4013be7 --- /dev/null +++ b/include/linux/raid/md_k.h @@ -0,0 +1,369 @@ +/* + 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 RAID6 8UL +#define RAID10 9UL +#define FAULTY 10UL +#define MAX_PERSONALITY 11UL + +#define LEVEL_MULTIPATH (-4) +#define LEVEL_LINEAR (-1) +#define LEVEL_FAULTY (-5) + +#define MaxSector (~(sector_t)0) +#define MD_THREAD_NAME_MAX 14 + +static inline int pers_to_level (int pers) +{ + switch (pers) { + case FAULTY: return LEVEL_FAULTY; + 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; + case RAID6: return 6; + case RAID10: return 10; + } + BUG(); + return MD_RESERVED; +} + +static inline int level_to_pers (int level) +{ + switch (level) { + case LEVEL_FAULTY: return FAULTY; + 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; + case 6: return RAID6; + case 10: return RAID10; + } + 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; + dev_t unit; + int md_minor; + struct list_head disks; + int sb_dirty; + int ro; + + struct gendisk *gendisk; + + /* 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 */ + sector_t curr_resync; /* blocks scheduled */ + unsigned long resync_mark; /* a recent timestamp */ + sector_t resync_mark_cnt;/* blocks written at resync_mark */ + + sector_t resync_max_sectors; /* may be set by personality */ + /* 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 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; + 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; +}; + + +static inline void rdev_dec_pending(mdk_rdev_t *rdev, mddev_t *mddev) +{ + int faulty = rdev->faulty; + 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_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); + int (*resize) (mddev_t *mddev, sector_t sectors); + int (*reshape) (mddev_t *mddev, int raid_disks); + int (*reconfig) (mddev_t *mddev, int layout, int chunk_size); +}; + + +static inline char * mdname (mddev_t * mddev) +{ + return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; +} + +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, 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) + +#endif + |