/*   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 or spare disk */#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 */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		1typedef 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        */#ifdef __BIG_ENDIAN	__u32 events_hi;	/*  7 high-order of superblock update count   */	__u32 events_lo;	/*  8 low-order of superblock update count    */#else	__u32 events_lo;	/*  7 low-order of superblock update count    */	__u32 events_hi;	/*  8 high-order of superblock update count   */#endif	__u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 9];	/*	 * 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;static inline __u64 md_event(mdp_super_t *sb) {	__u64 ev = sb->events_hi;	return (ev<<32)| sb->events_lo;}#endif