linux-sg2042/include/linux/raid/md_p.h

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/*
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
#include <linux/types.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_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_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_BITMAP_PRESENT 8 /* bitmap may be present nearby */
/*
* Notes:
* - if an array is being reshaped (restriped) in order to change the
* the number of active devices in the array, 'raid_disks' will be
* the larger of the old and new numbers. 'delta_disks' will
* be the "new - old". So if +ve, raid_disks is the new value, and
* "raid_disks-delta_disks" is the old. If -ve, raid_disks is the
* old value and "raid_disks+delta_disks" is the new (smaller) value.
*/
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 */
#ifdef __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;
static inline __u64 md_event(mdp_super_t *sb) {
__u64 ev = sb->events_hi;
return (ev<<32)| sb->events_lo;
}
md: need another print_sb for mdp_superblock_1 md_print_devices is called in two code path: MD_BUG(...), and md_ioctl with PRINT_RAID_DEBUG. it will dump out all in use md devices information; However, it wrongly processed two types of superblock in one: The header file <linux/raid/md_p.h> has defined two types of superblock, struct mdp_superblock_s (typedefed with mdp_super_t) according to md with metadata 0.90, and struct mdp_superblock_1 according to md with metadata 1.0 and later, These two types of superblock are very different, The md_print_devices code processed them both in mdp_super_t, that would lead to wrong informaton dump like: [ 6742.345877] [ 6742.345887] md: ********************************** [ 6742.345890] md: * <COMPLETE RAID STATE PRINTOUT> * [ 6742.345892] md: ********************************** [ 6742.345896] md1: <ram7><ram6><ram5><ram4> [ 6742.345907] md: rdev ram7, SZ:00065472 F:0 S:1 DN:3 [ 6742.345909] md: rdev superblock: [ 6742.345914] md: SB: (V:0.90.0) ID:<42ef13c7.598c059a.5f9f1645.801e9ee6> CT:4919856d [ 6742.345918] md: L5 S00065472 ND:4 RD:4 md1 LO:2 CS:65536 [ 6742.345922] md: UT:4919856d ST:1 AD:4 WD:4 FD:0 SD:0 CSUM:b7992907 E:00000001 [ 6742.345924] D 0: DISK<N:0,(1,8),R:0,S:6> [ 6742.345930] D 1: DISK<N:1,(1,10),R:1,S:6> [ 6742.345933] D 2: DISK<N:2,(1,12),R:2,S:6> [ 6742.345937] D 3: DISK<N:3,(1,14),R:3,S:6> [ 6742.345942] md: THIS: DISK<N:3,(1,14),R:3,S:6> ... [ 6742.346058] md0: <ram3><ram2><ram1><ram0> [ 6742.346067] md: rdev ram3, SZ:00065472 F:0 S:1 DN:3 [ 6742.346070] md: rdev superblock: [ 6742.346073] md: SB: (V:1.0.0) ID:<369aad81.00000000.00000000.00000000> CT:9a322a9c [ 6742.346077] md: L-1507699579 S976570180 ND:48 RD:0 md0 LO:65536 CS:196610 [ 6742.346081] md: UT:00000018 ST:0 AD:131048 WD:0 FD:8 SD:0 CSUM:00000000 E:00000000 [ 6742.346084] D 0: DISK<N:-1,(-1,-1),R:-1,S:-1> [ 6742.346089] D 1: DISK<N:-1,(-1,-1),R:-1,S:-1> [ 6742.346092] D 2: DISK<N:-1,(-1,-1),R:-1,S:-1> [ 6742.346096] D 3: DISK<N:-1,(-1,-1),R:-1,S:-1> [ 6742.346102] md: THIS: DISK<N:0,(0,0),R:0,S:0> ... [ 6742.346219] md: ********************************** [ 6742.346221] Here md1 is metadata 0.90.0, and md0 is metadata 1.2 After some more code to distinguish these two types of superblock, in this patch, it will generate dump information like: [ 7906.755790] [ 7906.755799] md: ********************************** [ 7906.755802] md: * <COMPLETE RAID STATE PRINTOUT> * [ 7906.755804] md: ********************************** [ 7906.755808] md1: <ram7><ram6><ram5><ram4> [ 7906.755819] md: rdev ram7, SZ:00065472 F:0 S:1 DN:3 [ 7906.755821] md: rdev superblock (MJ:0): [ 7906.755826] md: SB: (V:0.90.0) ID:<3fca7a0d.a612bfed.5f9f1645.801e9ee6> CT:491989f3 [ 7906.755830] md: L5 S00065472 ND:4 RD:4 md1 LO:2 CS:65536 [ 7906.755834] md: UT:491989f3 ST:1 AD:4 WD:4 FD:0 SD:0 CSUM:00fb52ad E:00000001 [ 7906.755836] D 0: DISK<N:0,(1,8),R:0,S:6> [ 7906.755842] D 1: DISK<N:1,(1,10),R:1,S:6> [ 7906.755845] D 2: DISK<N:2,(1,12),R:2,S:6> [ 7906.755849] D 3: DISK<N:3,(1,14),R:3,S:6> [ 7906.755855] md: THIS: DISK<N:3,(1,14),R:3,S:6> ... [ 7906.755972] md0: <ram3><ram2><ram1><ram0> [ 7906.755981] md: rdev ram3, SZ:00065472 F:0 S:1 DN:3 [ 7906.755984] md: rdev superblock (MJ:1): [ 7906.755989] md: SB: (V:1) (F:0) Array-ID:<5fbcf158:55aa:5fbe:9a79:1e939880dcbd> [ 7906.755990] md: Name: "DG5:0" CT:1226410480 [ 7906.755998] md: L5 SZ130944 RD:4 LO:2 CS:128 DO:24 DS:131048 SO:8 RO:0 [ 7906.755999] md: Dev:00000003 UUID: 9194d744:87f7:a448:85f2:7497b84ce30a [ 7906.756001] md: (F:0) UT:1226410480 Events:0 ResyncOffset:-1 CSUM:0dbcd829 [ 7906.756003] md: (MaxDev:384) ... [ 7906.756113] md: ********************************** [ 7906.756116] this md0 (metadata 1.2) information dumping is exactly according to struct mdp_superblock_1. Signed-off-by: Cheng Renquan <crquan@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Dan Williams <dan.j.williams@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-01-09 05:31:08 +08:00
#define MD_SUPERBLOCK_1_TIME_SEC_MASK ((1ULL<<40) - 1)
/*
* The version-1 superblock :
* All numeric fields are little-endian.
*
* total size: 256 bytes plus 2 per device.
* 1K allows 384 devices.
*/
struct mdp_superblock_1 {
/* constant array information - 128 bytes */
__le32 magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */
__le32 major_version; /* 1 */
__le32 feature_map; /* bit 0 set if 'bitmap_offset' is meaningful */
__le32 pad0; /* always set to 0 when writing */
__u8 set_uuid[16]; /* user-space generated. */
char set_name[32]; /* set and interpreted by user-space */
__le64 ctime; /* lo 40 bits are seconds, top 24 are microseconds or 0*/
__le32 level; /* -4 (multipath), -1 (linear), 0,1,4,5 */
__le32 layout; /* only for raid5 and raid10 currently */
__le64 size; /* used size of component devices, in 512byte sectors */
__le32 chunksize; /* in 512byte sectors */
__le32 raid_disks;
__le32 bitmap_offset; /* sectors after start of superblock that bitmap starts
* NOTE: signed, so bitmap can be before superblock
* only meaningful of feature_map[0] is set.
*/
/* These are only valid with feature bit '4' */
__le32 new_level; /* new level we are reshaping to */
__le64 reshape_position; /* next address in array-space for reshape */
__le32 delta_disks; /* change in number of raid_disks */
__le32 new_layout; /* new layout */
__le32 new_chunk; /* new chunk size (bytes) */
__u8 pad1[128-124]; /* set to 0 when written */
/* constant this-device information - 64 bytes */
__le64 data_offset; /* sector start of data, often 0 */
__le64 data_size; /* sectors in this device that can be used for data */
__le64 super_offset; /* sector start of this superblock */
__le64 recovery_offset;/* sectors before this offset (from data_offset) have been recovered */
__le32 dev_number; /* permanent identifier of this device - not role in raid */
__le32 cnt_corrected_read; /* number of read errors that were corrected by re-writing */
__u8 device_uuid[16]; /* user-space setable, ignored by kernel */
__u8 devflags; /* per-device flags. Only one defined...*/
#define WriteMostly1 1 /* mask for writemostly flag in above */
__u8 pad2[64-57]; /* set to 0 when writing */
/* array state information - 64 bytes */
__le64 utime; /* 40 bits second, 24 btes microseconds */
__le64 events; /* incremented when superblock updated */
__le64 resync_offset; /* data before this offset (from data_offset) known to be in sync */
__le32 sb_csum; /* checksum upto devs[max_dev] */
__le32 max_dev; /* size of devs[] array to consider */
__u8 pad3[64-32]; /* set to 0 when writing */
/* device state information. Indexed by dev_number.
* 2 bytes per device
* Note there are no per-device state flags. State information is rolled
* into the 'roles' value. If a device is spare or faulty, then it doesn't
* have a meaningful role.
*/
__le16 dev_roles[0]; /* role in array, or 0xffff for a spare, or 0xfffe for faulty */
};
/* feature_map bits */
#define MD_FEATURE_BITMAP_OFFSET 1
#define MD_FEATURE_RECOVERY_OFFSET 2 /* recovery_offset is present and
* must be honoured
*/
#define MD_FEATURE_RESHAPE_ACTIVE 4
#define MD_FEATURE_ALL (1|2|4)
#endif