[mirror_ubuntu-bionic-kernel.git] / include / linux / raid / md_k.h

/*
   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 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;

	spinlock_t			write_lock;
	struct bio_list			write_list;

	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
Commit	Line	Data
1da177e4 LT	1	/*
	2	md_k.h : kernel internal structure of the Linux MD driver
	3	Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
	4
	5	This program is free software; you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License as published by
	7	the Free Software Foundation; either version 2, or (at your option)
	8	any later version.
	9
	10	You should have received a copy of the GNU General Public License
	11	(for example /usr/src/linux/COPYING); if not, write to the Free
	12	Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	13	*/
	14
	15	#ifndef _MD_K_H
	16	#define _MD_K_H
	17
06d91a5f N	18	/* and dm-bio-list.h is not under include/linux because.... ??? */
	19	#include "../../../drivers/md/dm-bio-list.h"
	20
1da177e4 LT	21	#define MD_RESERVED 0UL
	22	#define LINEAR 1UL
	23	#define RAID0 2UL
	24	#define RAID1 3UL
	25	#define RAID5 4UL
	26	#define TRANSLUCENT 5UL
	27	#define HSM 6UL
	28	#define MULTIPATH 7UL
	29	#define RAID6 8UL
	30	#define RAID10 9UL
	31	#define FAULTY 10UL
	32	#define MAX_PERSONALITY 11UL
	33
	34	#define LEVEL_MULTIPATH (-4)
	35	#define LEVEL_LINEAR (-1)
	36	#define LEVEL_FAULTY (-5)
	37
	38	#define MaxSector (~(sector_t)0)
	39	#define MD_THREAD_NAME_MAX 14
	40
	41	static inline int pers_to_level (int pers)
	42	{
	43	switch (pers) {
	44	case FAULTY: return LEVEL_FAULTY;
	45	case MULTIPATH: return LEVEL_MULTIPATH;
	46	case HSM: return -3;
	47	case TRANSLUCENT: return -2;
	48	case LINEAR: return LEVEL_LINEAR;
	49	case RAID0: return 0;
	50	case RAID1: return 1;
	51	case RAID5: return 5;
	52	case RAID6: return 6;
	53	case RAID10: return 10;
	54	}
	55	BUG();
	56	return MD_RESERVED;
	57	}
	58
	59	static inline int level_to_pers (int level)
	60	{
	61	switch (level) {
	62	case LEVEL_FAULTY: return FAULTY;
	63	case LEVEL_MULTIPATH: return MULTIPATH;
	64	case -3: return HSM;
	65	case -2: return TRANSLUCENT;
	66	case LEVEL_LINEAR: return LINEAR;
	67	case 0: return RAID0;
	68	case 1: return RAID1;
	69	case 4:
	70	case 5: return RAID5;
	71	case 6: return RAID6;
	72	case 10: return RAID10;
	73	}
	74	return MD_RESERVED;
	75	}
	76
	77	typedef struct mddev_s mddev_t;
	78	typedef struct mdk_rdev_s mdk_rdev_t;
	79
	80	#define MAX_MD_DEVS 256 /* Max number of md dev */
	81
	82	/*
	83	* options passed in raidrun:
	84	*/
85
86	#define MAX_CHUNK_SIZE (4096*1024)
87
88	/*
89	* default readahead
90	*/
91
92	static inline int disk_faulty(mdp_disk_t * d)
93	{
94	return d->state & (1 << MD_DISK_FAULTY);
95	}
96
97	static inline int disk_active(mdp_disk_t * d)
98	{
99	return d->state & (1 << MD_DISK_ACTIVE);
100	}
101
102	static inline int disk_sync(mdp_disk_t * d)
103	{
104	return d->state & (1 << MD_DISK_SYNC);
105	}
106
107	static inline int disk_spare(mdp_disk_t * d)
108	{
109	return !disk_sync(d) && !disk_active(d) && !disk_faulty(d);
110	}
111
112	static inline int disk_removed(mdp_disk_t * d)
113	{
114	return d->state & (1 << MD_DISK_REMOVED);
115	}
116
117	static inline void mark_disk_faulty(mdp_disk_t * d)
118	{
119	d->state \|= (1 << MD_DISK_FAULTY);
120	}
121
122	static inline void mark_disk_active(mdp_disk_t * d)
123	{
124	d->state \|= (1 << MD_DISK_ACTIVE);
125	}
126
127	static inline void mark_disk_sync(mdp_disk_t * d)
128	{
129	d->state \|= (1 << MD_DISK_SYNC);
130	}
131
132	static inline void mark_disk_spare(mdp_disk_t * d)
133	{
134	d->state = 0;
135	}
136
137	static inline void mark_disk_removed(mdp_disk_t * d)
138	{
139	d->state = (1 << MD_DISK_FAULTY) \| (1 << MD_DISK_REMOVED);
140	}
141
142	static inline void mark_disk_inactive(mdp_disk_t * d)
143	{
144	d->state &= ~(1 << MD_DISK_ACTIVE);
145	}
146
147	static inline void mark_disk_nonsync(mdp_disk_t * d)
148	{
149	d->state &= ~(1 << MD_DISK_SYNC);
150	}
151
152	/*
153	* MD's 'extended' device
154	*/
155	struct mdk_rdev_s
156	{
157	struct list_head same_set; /* RAID devices within the same set */
158
159	sector_t size; /* Device size (in blocks) */
160	mddev_t mddev; / RAID array if running */
161	unsigned long last_events; /* IO event timestamp */
162
163	struct block_device bdev; / block device handle */
164
165	struct page *sb_page;
166	int sb_loaded;
167	sector_t data_offset; /* start of data in array */
168	sector_t sb_offset;
169	int preferred_minor; /* autorun support */
170
171	/* A device can be in one of three states based on two flags:
172	* Not working: faulty==1 in_sync==0
173	* Fully working: faulty==0 in_sync==1
174	* Working, but not
175	* in sync with array
176	* faulty==0 in_sync==0
177	*
178	* It can never have faulty==1, in_sync==1
179	* This reduces the burden of testing multiple flags in many cases
180	*/
181	int faulty; /* if faulty do not issue IO requests */
182	int in_sync; /* device is a full member of the array */
183
184	int desc_nr; /* descriptor index in the superblock */
185	int raid_disk; /* role of device in array */
186
187	atomic_t nr_pending; /* number of pending requests.
188	* only maintained for arrays that
189	* support hot removal
190	*/
191	};
192
193	typedef struct mdk_personality_s mdk_personality_t;
194
195	struct mddev_s
196	{
197	void *private;
198	mdk_personality_t *pers;
199	dev_t unit;
200	int md_minor;
201	struct list_head disks;
202	int sb_dirty;
203	int ro;
204
205	struct gendisk *gendisk;
206
207	/* Superblock information */
208	int major_version,
209	minor_version,
210	patch_version;
211	int persistent;
212	int chunk_size;
213	time_t ctime, utime;
214	int level, layout;
215	int raid_disks;
216	int max_disks;
217	sector_t size; /* used size of component devices */
218	sector_t array_size; /* exported array size */
219	__u64 events;
220
221	char uuid[16];
222
223	struct mdk_thread_s thread; / management thread */
224	struct mdk_thread_s sync_thread; / doing resync or reconstruct */
225	sector_t curr_resync; /* blocks scheduled */
226	unsigned long resync_mark; /* a recent timestamp */
227	sector_t resync_mark_cnt;/* blocks written at resync_mark */
228
229	sector_t resync_max_sectors; /* may be set by personality */
230	/* recovery/resync flags
231	* NEEDED: we might need to start a resync/recover
232	* RUNNING: a thread is running, or about to be started
233	* SYNC: actually doing a resync, not a recovery
234	* ERR: and IO error was detected - abort the resync/recovery
235	* INTR: someone requested a (clean) early abort.
236	* DONE: thread is done and is waiting to be reaped
237	*/
238	#define MD_RECOVERY_RUNNING 0
239	#define MD_RECOVERY_SYNC 1
240	#define MD_RECOVERY_ERR 2
241	#define MD_RECOVERY_INTR 3
242	#define MD_RECOVERY_DONE 4
243	#define MD_RECOVERY_NEEDED 5
244	unsigned long recovery;
245
246	int in_sync; /* know to not need resync */
247	struct semaphore reconfig_sem;
248	atomic_t active;
249
250	int changed; /* true if we might need to reread partition info */
251	int degraded; /* whether md should consider
252	* adding a spare
253	*/
254
255	atomic_t recovery_active; /* blocks scheduled, but not written */
256	wait_queue_head_t recovery_wait;
257	sector_t recovery_cp;
06d91a5f N	258
	259	spinlock_t write_lock;
	260	struct bio_list write_list;
	261
1da177e4 LT	262	unsigned int safemode; /* if set, update "clean" superblock
	263	* when no writes pending.
	264	*/
	265	unsigned int safemode_delay;
	266	struct timer_list safemode_timer;
	267	atomic_t writes_pending;
	268	request_queue_t queue; / for plugging ... */
	269
	270	struct list_head all_mddevs;
	271	};
	272
	273
	274	static inline void rdev_dec_pending(mdk_rdev_t rdev, mddev_t mddev)
	275	{
	276	int faulty = rdev->faulty;
	277	if (atomic_dec_and_test(&rdev->nr_pending) && faulty)
	278	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
	279	}
	280
	281	static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
	282	{
	283	atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
	284	}
	285
	286	struct mdk_personality_s
	287	{
	288	char *name;
	289	struct module *owner;
	290	int (make_request)(request_queue_t q, struct bio *bio);
	291	int (run)(mddev_t mddev);
	292	int (stop)(mddev_t mddev);
	293	void (status)(struct seq_file seq, mddev_t *mddev);
	294	/* error_handler must set ->faulty and clear ->in_sync
	295	* if appropriate, and should abort recovery if needed
	296	*/
	297	void (error_handler)(mddev_t mddev, mdk_rdev_t *rdev);
	298	int (hot_add_disk) (mddev_t mddev, mdk_rdev_t *rdev);
	299	int (hot_remove_disk) (mddev_t mddev, int number);
	300	int (spare_active) (mddev_t mddev);
	301	int (sync_request)(mddev_t mddev, sector_t sector_nr, int go_faster);
	302	int (resize) (mddev_t mddev, sector_t sectors);
	303	int (reshape) (mddev_t mddev, int raid_disks);
	304	int (reconfig) (mddev_t mddev, int layout, int chunk_size);
	305	};
	306
	307
	308	static inline char * mdname (mddev_t * mddev)
	309	{
	310	return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
	311	}
	312
	313	extern mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr);
	314
	315	/*
	316	* iterates through some rdev ringlist. It's safe to remove the
	317	* current 'rdev'. Dont touch 'tmp' though.
	318	*/
	319	#define ITERATE_RDEV_GENERIC(head,rdev,tmp) \
	320	\
	321	for ((tmp) = (head).next; \
	322	(rdev) = (list_entry((tmp), mdk_rdev_t, same_set)), \
	323	(tmp) = (tmp)->next, (tmp)->prev != &(head) \
	324	; )
	325	/*
326	* iterates through the 'same array disks' ringlist
327	*/
328	#define ITERATE_RDEV(mddev,rdev,tmp) \
329	ITERATE_RDEV_GENERIC((mddev)->disks,rdev,tmp)
330
331	/*
332	* Iterates through 'pending RAID disks'
333	*/
334	#define ITERATE_RDEV_PENDING(rdev,tmp) \
335	ITERATE_RDEV_GENERIC(pending_raid_disks,rdev,tmp)
336
337	typedef struct mdk_thread_s {
338	void (run) (mddev_t mddev);
339	mddev_t *mddev;
340	wait_queue_head_t wqueue;
341	unsigned long flags;
342	struct completion *event;
343	struct task_struct *tsk;
344	const char *name;
345	} mdk_thread_t;
346
347	#define THREAD_WAKEUP 0
348
349	#define __wait_event_lock_irq(wq, condition, lock, cmd) \
350	do { \
351	wait_queue_t __wait; \
352	init_waitqueue_entry(&__wait, current); \
353	\
354	add_wait_queue(&wq, &__wait); \
355	for (;;) { \
356	set_current_state(TASK_UNINTERRUPTIBLE); \
357	if (condition) \
358	break; \
359	spin_unlock_irq(&lock); \
360	cmd; \
361	schedule(); \
362	spin_lock_irq(&lock); \
363	} \
364	current->state = TASK_RUNNING; \
365	remove_wait_queue(&wq, &__wait); \
366	} while (0)
367
368	#define wait_event_lock_irq(wq, condition, lock, cmd) \
369	do { \
370	if (condition) \
371	break; \
372	__wait_event_lock_irq(wq, condition, lock, cmd); \
373	} while (0)
374
375	#endif
376