/* 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 /* and dm-bio-list.h is not under include/linux because.... ??? */ #include "../../../drivers/md/dm-bio-list.h" #define LEVEL_MULTIPATH (-4) #define LEVEL_LINEAR (-1) #define LEVEL_FAULTY (-5) /* we need a value for 'no level specified' and 0 * means 'raid0', so we need something else. This is * for internal use only */ #define LEVEL_NONE (-1000000) #define MaxSector (~(sector_t)0) #define MD_THREAD_NAME_MAX 14 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) /* * 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 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 BarriersNotsupp 5 /* BIO_RW_BARRIER is not supported */ int desc_nr; /* descriptor index in the superblock */ int raid_disk; /* role of device in array */ 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 */ 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 mddev_s { void *private; struct mdk_personality *pers; dev_t unit; int md_minor; struct list_head disks; int sb_dirty; int ro; struct gendisk *gendisk; struct kobject kobj; /* 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 */ sector_t resync_mismatches; /* count of sectors where * parity/replica mismatch found */ 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 * 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 * REQUEST: user-space has requested a sync (used with SYNC) * CHECK: user-space request for for check-only, no repair */ #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 #define MD_RECOVERY_REQUESTED 6 #define MD_RECOVERY_CHECK 7 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 */ int barriers_work; /* initialised to true, cleared as soon * as a barrier request to slave * fails. Only supported */ struct bio *biolist; /* bios that need to be retried * because BIO_RW_BARRIER is not supported */ atomic_t recovery_active; /* blocks scheduled, but not written */ wait_queue_head_t recovery_wait; sector_t recovery_cp; 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; request_queue_t *queue; /* for plugging ... */ atomic_t write_behind; /* outstanding async IO */ unsigned int max_write_behind; /* 0 = sync */ struct bitmap *bitmap; /* the bitmap for the device */ struct file *bitmap_file; /* the bitmap file */ long bitmap_offset; /* offset from superblock of * start of bitmap. May be * negative, but not '0' */ long default_bitmap_offset; /* this is the offset to use when * hot-adding a bitmap. It should * eventually be settable by sysfs. */ struct list_head all_mddevs; }; 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)(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); sector_t (*sync_request)(mddev_t *mddev, sector_t sector_nr, int *skipped, 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); /* quiesce moves between quiescence states * 0 - fully active * 1 - no new requests allowed * others - reserved */ void (*quiesce) (mddev_t *mddev, int state); }; struct md_sysfs_entry { struct attribute attr; ssize_t (*show)(mddev_t *, char *); ssize_t (*store)(mddev_t *, const char *, size_t); }; 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 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) #endif