include/linux/raid/md_k.h - kernel/msm-4.19 - Gitiles

 /*
    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
	/*
	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