ignore open [method] disabled ˆÇÆ „ o‰¯ÅÁÃ>4/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ /* 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. */ #ifndef _MD_P_H #define _MD_P_H #include #include /* * 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_NEW_SIZE_SECTORS(x) ((x & ~(MD_RESERVED_SECTORS - 1)) - MD_RESERVED_SECTORS) #define MD_SB_BYTES 4096 #define MD_SB_WORDS (MD_SB_BYTES / 4) #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 */ #define MD_DISK_CLUSTER_ADD 4 /* Initiate a disk add across the cluster * For clustered enviroments only. */ #define MD_DISK_CANDIDATE 5 /* disk is added as spare (local) until confirmed * For clustered enviroments only. */ #define MD_DISK_FAILFAST 10 /* Send REQ_FAILFAST if there are multiple * devices available - and don't try to * correct read errors. */ #define MD_DISK_WRITEMOSTLY 9 /* disk is "write-mostly" is RAID1 config. * read requests will only be sent here in * dire need */ #define MD_DISK_JOURNAL 18 /* disk is used as the write journal in RAID-5/6 */ #define MD_DISK_ROLE_SPARE 0xffff #define MD_DISK_ROLE_FAULTY 0xfffe #define MD_DISK_ROLE_JOURNAL 0xfffd #define MD_DISK_ROLE_MAX 0xff00 /* max value of regular disk role */ 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_CLUSTERED 5 /* MD is clustered */ #define MD_SB_BITMAP