[thirdparty/mdadm.git] / md_p.h

/*
   md_p.h : physical layout of Linux RAID devices
          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_P_H
#define _MD_P_H

/*
 * RAID superblock.
 *
 * The RAID superblock maintains some statistics on each RAID configuration.
 * Each real device in the RAID set contains it near the end of the device.
 * Some of the ideas are copied from the ext2fs implementation.
 *
 * We currently use 4096 bytes as follows:
 *
 *	word offset	function
 *
 *	   0  -    31	Constant generic RAID device information.
 *        32  -    63   Generic state information.
 *	  64  -   127	Personality specific information.
 *	 128  -   511	12 32-words descriptors of the disks in the raid set.
 *	 512  -   911	Reserved.
 *	 912  -  1023	Disk specific descriptor.
 */

/*
 * If x is the real device size in bytes, we return an apparent size of:
 *
 *	y = (x & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES
 *
 * and place the 4kB superblock at offset y.
 */
#define MD_RESERVED_BYTES		(64 * 1024)
#define MD_RESERVED_SECTORS		(MD_RESERVED_BYTES / 512)
#define MD_RESERVED_BLOCKS		(MD_RESERVED_BYTES / BLOCK_SIZE)

#define MD_NEW_SIZE_SECTORS(x)		((x & ~(MD_RESERVED_SECTORS - 1)) - MD_RESERVED_SECTORS)
#define MD_NEW_SIZE_BLOCKS(x)		((x & ~(MD_RESERVED_BLOCKS - 1)) - MD_RESERVED_BLOCKS)

#define MD_SB_BYTES			4096
#define MD_SB_WORDS			(MD_SB_BYTES / 4)
#define MD_SB_BLOCKS			(MD_SB_BYTES / BLOCK_SIZE)
#define MD_SB_SECTORS			(MD_SB_BYTES / 512)

/*
 * The following are counted in 32-bit words
 */
#define	MD_SB_GENERIC_OFFSET		0
#define MD_SB_PERSONALITY_OFFSET	64
#define MD_SB_DISKS_OFFSET		128
#define MD_SB_DESCRIPTOR_OFFSET		992

#define MD_SB_GENERIC_CONSTANT_WORDS	32
#define MD_SB_GENERIC_STATE_WORDS	32
#define MD_SB_GENERIC_WORDS		(MD_SB_GENERIC_CONSTANT_WORDS + MD_SB_GENERIC_STATE_WORDS)
#define MD_SB_PERSONALITY_WORDS		64
#define MD_SB_DESCRIPTOR_WORDS		32
#define MD_SB_DISKS			27
#define MD_SB_DISKS_WORDS		(MD_SB_DISKS*MD_SB_DESCRIPTOR_WORDS)
#define MD_SB_RESERVED_WORDS		(1024 - MD_SB_GENERIC_WORDS - MD_SB_PERSONALITY_WORDS - MD_SB_DISKS_WORDS - MD_SB_DESCRIPTOR_WORDS)
#define MD_SB_EQUAL_WORDS		(MD_SB_GENERIC_WORDS + MD_SB_PERSONALITY_WORDS + MD_SB_DISKS_WORDS)

/*
 * Device "operational" state bits
 */
#define MD_DISK_FAULTY		0 /* disk is faulty / operational */
#define MD_DISK_ACTIVE		1 /* disk is running but may not be in sync */
#define MD_DISK_SYNC		2 /* disk is in sync with the raid set */
#define MD_DISK_REMOVED		3 /* disk is in sync with the raid set */

#define	MD_DISK_WRITEMOSTLY	9 /* disk is "write-mostly" is RAID1 config.
				   * read requests will only be sent here in
				   * dire need
				   */

typedef struct mdp_device_descriptor_s {
	__u32 number;		/* 0 Device number in the entire set	      */
	__u32 major;		/* 1 Device major number		      */
	__u32 minor;		/* 2 Device minor number		      */
	__u32 raid_disk;	/* 3 The role of the device in the raid set   */
	__u32 state;		/* 4 Operational state			      */
	__u32 reserved[MD_SB_DESCRIPTOR_WORDS - 5];
} mdp_disk_t;

#define MD_SB_MAGIC		0xa92b4efc

/*
 * Superblock state bits
 */
#define MD_SB_CLEAN		0
#define MD_SB_ERRORS		1
#define MD_SB_BBM_ERRORS	2
#define MD_SB_BLOCK_CONTAINER_RESHAPE 3 /* block container wide reshapes */
#define MD_SB_BLOCK_VOLUME	4 /* block activation of array, other arrays
				   * in container can be activated */
#define	MD_SB_BITMAP_PRESENT	8 /* bitmap may be present nearby */

typedef struct mdp_superblock_s {
	/*
	 * Constant generic information
	 */
	__u32 md_magic;		/*  0 MD identifier 			      */
	__u32 major_version;	/*  1 major version to which the set conforms */
	__u32 minor_version;	/*  2 minor version ...			      */
	__u32 patch_version;	/*  3 patchlevel version ...		      */
	__u32 gvalid_words;	/*  4 Number of used words in this section    */
	__u32 set_uuid0;	/*  5 Raid set identifier		      */
	__u32 ctime;		/*  6 Creation time			      */
	__u32 level;		/*  7 Raid personality			      */
	__u32 size;		/*  8 Apparent size of each individual disk   */
	__u32 nr_disks;		/*  9 total disks in the raid set	      */
	__u32 raid_disks;	/* 10 disks in a fully functional raid set    */
	__u32 md_minor;		/* 11 preferred MD minor device number	      */
	__u32 not_persistent;	/* 12 does it have a persistent superblock    */
	__u32 set_uuid1;	/* 13 Raid set identifier #2		      */
	__u32 set_uuid2;	/* 14 Raid set identifier #3		      */
	__u32 set_uuid3;	/* 15 Raid set identifier #4		      */
	__u32 gstate_creserved[MD_SB_GENERIC_CONSTANT_WORDS - 16];

	/*
	 * Generic state information
	 */
	__u32 utime;		/*  0 Superblock update time		      */
	__u32 state;		/*  1 State bits (clean, ...)		      */
	__u32 active_disks;	/*  2 Number of currently active disks	      */
	__u32 working_disks;	/*  3 Number of working disks		      */
	__u32 failed_disks;	/*  4 Number of failed disks		      */
	__u32 spare_disks;	/*  5 Number of spare disks		      */
	__u32 sb_csum;		/*  6 checksum of the whole superblock        */
#if  __BYTE_ORDER ==  __BIG_ENDIAN
	__u32 events_hi;	/*  7 high-order of superblock update count   */
	__u32 events_lo;	/*  8 low-order of superblock update count    */
	__u32 cp_events_hi;	/*  9 high-order of checkpoint update count   */
	__u32 cp_events_lo;	/* 10 low-order of checkpoint update count    */
#else
	__u32 events_lo;	/*  7 low-order of superblock update count    */
	__u32 events_hi;	/*  8 high-order of superblock update count   */
	__u32 cp_events_lo;	/*  9 low-order of checkpoint update count    */
	__u32 cp_events_hi;	/* 10 high-order of checkpoint update count   */
#endif
	__u32 recovery_cp;	/* 11 recovery checkpoint sector count	      */
	/* There are only valid for minor_version > 90 */
	__u64 reshape_position;	/* 12,13 next address in array-space for reshape */
	__u32 new_level;	/* 14 new level we are reshaping to	      */
	__u32 delta_disks;	/* 15 change in number of raid_disks	      */
	__u32 new_layout;	/* 16 new layout			      */
	__u32 new_chunk;	/* 17 new chunk size (bytes)		      */
	__u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 18];

	/*
	 * Personality information
	 */
	__u32 layout;		/*  0 the array's physical layout	      */
	__u32 chunk_size;	/*  1 chunk size in bytes		      */
	__u32 root_pv;		/*  2 LV root PV */
	__u32 root_block;	/*  3 LV root block */
	__u32 pstate_reserved[MD_SB_PERSONALITY_WORDS - 4];

	/*
	 * Disks information
	 */
	mdp_disk_t disks[MD_SB_DISKS];

	/*
	 * Reserved
	 */
	__u32 reserved[MD_SB_RESERVED_WORDS];

	/*
	 * Active descriptor
	 */
	mdp_disk_t this_disk;

} mdp_super_t;

#ifdef __TINYC__
typedef unsigned long long __u64;
#endif

static inline __u64 md_event(mdp_super_t *sb) {
	__u64 ev = sb->events_hi;
	return (ev<<32)| sb->events_lo;
}

#endif
Commit	Line	Data
64c4757e NB	1	/*
	2	md_p.h : physical layout of Linux RAID devices
	3	Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
aba69144	4
64c4757e NB	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.
aba69144	9
64c4757e NB	10	You should have received a copy of the GNU General Public License
64c4757e NB	11	(for example /usr/src/linux/COPYING); if not, write to the Free
aba69144	12	Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
64c4757e NB	13	*/
	14
	15	#ifndef _MD_P_H
	16	#define _MD_P_H
	17
	18	/*
	19	* RAID superblock.
	20	*
	21	* The RAID superblock maintains some statistics on each RAID configuration.
	22	* Each real device in the RAID set contains it near the end of the device.
	23	* Some of the ideas are copied from the ext2fs implementation.
	24	*
	25	* We currently use 4096 bytes as follows:
	26	*
	27	* word offset function
	28	*
	29	* 0 - 31 Constant generic RAID device information.
	30	* 32 - 63 Generic state information.
	31	* 64 - 127 Personality specific information.
	32	* 128 - 511 12 32-words descriptors of the disks in the raid set.
	33	* 512 - 911 Reserved.
	34	* 912 - 1023 Disk specific descriptor.
	35	*/
	36
	37	/*
	38	* If x is the real device size in bytes, we return an apparent size of:
	39	*
	40	* y = (x & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES
	41	*
	42	* and place the 4kB superblock at offset y.
	43	*/
	44	#define MD_RESERVED_BYTES (64 * 1024)
	45	#define MD_RESERVED_SECTORS (MD_RESERVED_BYTES / 512)
	46	#define MD_RESERVED_BLOCKS (MD_RESERVED_BYTES / BLOCK_SIZE)
	47
	48	#define MD_NEW_SIZE_SECTORS(x) ((x & ~(MD_RESERVED_SECTORS - 1)) - MD_RESERVED_SECTORS)
	49	#define MD_NEW_SIZE_BLOCKS(x) ((x & ~(MD_RESERVED_BLOCKS - 1)) - MD_RESERVED_BLOCKS)
	50
	51	#define MD_SB_BYTES 4096
	52	#define MD_SB_WORDS (MD_SB_BYTES / 4)
	53	#define MD_SB_BLOCKS (MD_SB_BYTES / BLOCK_SIZE)
	54	#define MD_SB_SECTORS (MD_SB_BYTES / 512)
	55
	56	/*
	57	* The following are counted in 32-bit words
	58	*/
	59	#define MD_SB_GENERIC_OFFSET 0
	60	#define MD_SB_PERSONALITY_OFFSET 64
	61	#define MD_SB_DISKS_OFFSET 128
	62	#define MD_SB_DESCRIPTOR_OFFSET 992
	63
	64	#define MD_SB_GENERIC_CONSTANT_WORDS 32
	65	#define MD_SB_GENERIC_STATE_WORDS 32
	66	#define MD_SB_GENERIC_WORDS (MD_SB_GENERIC_CONSTANT_WORDS + MD_SB_GENERIC_STATE_WORDS)
	67	#define MD_SB_PERSONALITY_WORDS 64
	68	#define MD_SB_DESCRIPTOR_WORDS 32
	69	#define MD_SB_DISKS 27
	70	#define MD_SB_DISKS_WORDS (MD_SB_DISKS*MD_SB_DESCRIPTOR_WORDS)
	71	#define MD_SB_RESERVED_WORDS (1024 - MD_SB_GENERIC_WORDS - MD_SB_PERSONALITY_WORDS - MD_SB_DISKS_WORDS - MD_SB_DESCRIPTOR_WORDS)
	72	#define MD_SB_EQUAL_WORDS (MD_SB_GENERIC_WORDS + MD_SB_PERSONALITY_WORDS + MD_SB_DISKS_WORDS)
	73
	74	/*
	75	* Device "operational" state bits
	76	*/
77	#define MD_DISK_FAULTY 0 /* disk is faulty / operational */
f22385f9	78	#define MD_DISK_ACTIVE 1 /* disk is running but may not be in sync */
64c4757e NB	79	#define MD_DISK_SYNC 2 /* disk is in sync with the raid set */
	80	#define MD_DISK_REMOVED 3 /* disk is in sync with the raid set */
	81
dfd4d8ee	82	#define MD_DISK_WRITEMOSTLY 9 /* disk is "write-mostly" is RAID1 config.
aba69144	83	* read requests will only be sent here in
dfd4d8ee NB	84	* dire need
	85	*/
	86
64c4757e NB	87	typedef struct mdp_device_descriptor_s {
	88	__u32 number; /* 0 Device number in the entire set */
	89	__u32 major; /* 1 Device major number */
	90	__u32 minor; /* 2 Device minor number */
	91	__u32 raid_disk; /* 3 The role of the device in the raid set */
	92	__u32 state; /* 4 Operational state */
	93	__u32 reserved[MD_SB_DESCRIPTOR_WORDS - 5];
	94	} mdp_disk_t;
	95
	96	#define MD_SB_MAGIC 0xa92b4efc
	97
	98	/*
	99	* Superblock state bits
	100	*/
	101	#define MD_SB_CLEAN 0
	102	#define MD_SB_ERRORS 1
a06d022d	103	#define MD_SB_BBM_ERRORS 2
81219e70 LM	104	#define MD_SB_BLOCK_CONTAINER_RESHAPE 3 /* block container wide reshapes */
	105	#define MD_SB_BLOCK_VOLUME 4 /* block activation of array, other arrays
	106	* in container can be activated */
55935d51 NB	107	#define MD_SB_BITMAP_PRESENT 8 /* bitmap may be present nearby */
55935d51 NB	108
64c4757e NB	109	typedef struct mdp_superblock_s {
	110	/*
	111	* Constant generic information
	112	*/
	113	__u32 md_magic; /* 0 MD identifier */
	114	__u32 major_version; /* 1 major version to which the set conforms */
	115	__u32 minor_version; /* 2 minor version ... */
	116	__u32 patch_version; /* 3 patchlevel version ... */
	117	__u32 gvalid_words; /* 4 Number of used words in this section */
	118	__u32 set_uuid0; /* 5 Raid set identifier */
	119	__u32 ctime; /* 6 Creation time */
	120	__u32 level; /* 7 Raid personality */
	121	__u32 size; /* 8 Apparent size of each individual disk */
	122	__u32 nr_disks; /* 9 total disks in the raid set */
	123	__u32 raid_disks; /* 10 disks in a fully functional raid set */
	124	__u32 md_minor; /* 11 preferred MD minor device number */
	125	__u32 not_persistent; /* 12 does it have a persistent superblock */
	126	__u32 set_uuid1; /* 13 Raid set identifier #2 */
	127	__u32 set_uuid2; /* 14 Raid set identifier #3 */
	128	__u32 set_uuid3; /* 15 Raid set identifier #4 */
	129	__u32 gstate_creserved[MD_SB_GENERIC_CONSTANT_WORDS - 16];
	130
	131	/*
	132	* Generic state information
	133	*/
	134	__u32 utime; /* 0 Superblock update time */
	135	__u32 state; /* 1 State bits (clean, ...) */
	136	__u32 active_disks; /* 2 Number of currently active disks */
	137	__u32 working_disks; /* 3 Number of working disks */
	138	__u32 failed_disks; /* 4 Number of failed disks */
	139	__u32 spare_disks; /* 5 Number of spare disks */
	140	__u32 sb_csum; /* 6 checksum of the whole superblock */
52826846	141	#if __BYTE_ORDER == __BIG_ENDIAN
64c4757e NB	142	__u32 events_hi; /* 7 high-order of superblock update count */
64c4757e NB	143	__u32 events_lo; /* 8 low-order of superblock update count */
e5329c37 NB	144	__u32 cp_events_hi; /* 9 high-order of checkpoint update count */
e5329c37 NB	145	__u32 cp_events_lo; /* 10 low-order of checkpoint update count */
64c4757e NB	146	#else
	147	__u32 events_lo; /* 7 low-order of superblock update count */
	148	__u32 events_hi; /* 8 high-order of superblock update count */
e5329c37 NB	149	__u32 cp_events_lo; /* 9 low-order of checkpoint update count */
e5329c37 NB	150	__u32 cp_events_hi; /* 10 high-order of checkpoint update count */
64c4757e	151	#endif
e5329c37	152	__u32 recovery_cp; /* 11 recovery checkpoint sector count */
b674b5b8 NB	153	/* There are only valid for minor_version > 90 */
	154	__u64 reshape_position; /* 12,13 next address in array-space for reshape */
	155	__u32 new_level; /* 14 new level we are reshaping to */
	156	__u32 delta_disks; /* 15 change in number of raid_disks */
	157	__u32 new_layout; /* 16 new layout */
	158	__u32 new_chunk; /* 17 new chunk size (bytes) */
	159	__u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 18];
64c4757e NB	160
	161	/*
	162	* Personality information
	163	*/
	164	__u32 layout; /* 0 the array's physical layout */
	165	__u32 chunk_size; /* 1 chunk size in bytes */
	166	__u32 root_pv; /* 2 LV root PV */
	167	__u32 root_block; /* 3 LV root block */
	168	__u32 pstate_reserved[MD_SB_PERSONALITY_WORDS - 4];
	169
	170	/*
	171	* Disks information
	172	*/
	173	mdp_disk_t disks[MD_SB_DISKS];
	174
	175	/*
	176	* Reserved
	177	*/
	178	__u32 reserved[MD_SB_RESERVED_WORDS];
	179
	180	/*
	181	* Active descriptor
	182	*/
	183	mdp_disk_t this_disk;
	184
	185	} mdp_super_t;
	186
5787fa49 NB	187	#ifdef __TINYC__
	188	typedef unsigned long long __u64;
	189	#endif
	190
64c4757e NB	191	static inline __u64 md_event(mdp_super_t *sb) {
	192	__u64 ev = sb->events_hi;
	193	return (ev<<32)\| sb->events_lo;
	194	}
	195
aba69144	196	#endif
64c4757e	197