diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/linux/raid/md_p.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/linux/raid/md_p.h')
-rw-r--r-- | include/linux/raid/md_p.h | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/include/linux/raid/md_p.h b/include/linux/raid/md_p.h new file mode 100644 index 000000000000..8ba95d67329f --- /dev/null +++ b/include/linux/raid/md_p.h | |||
@@ -0,0 +1,230 @@ | |||
1 | /* | ||
2 | md_p.h : physical layout of Linux RAID devices | ||
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_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 */ | ||
78 | #define MD_DISK_ACTIVE 1 /* disk is running or spare disk */ | ||
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 | |||
82 | typedef struct mdp_device_descriptor_s { | ||
83 | __u32 number; /* 0 Device number in the entire set */ | ||
84 | __u32 major; /* 1 Device major number */ | ||
85 | __u32 minor; /* 2 Device minor number */ | ||
86 | __u32 raid_disk; /* 3 The role of the device in the raid set */ | ||
87 | __u32 state; /* 4 Operational state */ | ||
88 | __u32 reserved[MD_SB_DESCRIPTOR_WORDS - 5]; | ||
89 | } mdp_disk_t; | ||
90 | |||
91 | #define MD_SB_MAGIC 0xa92b4efc | ||
92 | |||
93 | /* | ||
94 | * Superblock state bits | ||
95 | */ | ||
96 | #define MD_SB_CLEAN 0 | ||
97 | #define MD_SB_ERRORS 1 | ||
98 | |||
99 | typedef struct mdp_superblock_s { | ||
100 | /* | ||
101 | * Constant generic information | ||
102 | */ | ||
103 | __u32 md_magic; /* 0 MD identifier */ | ||
104 | __u32 major_version; /* 1 major version to which the set conforms */ | ||
105 | __u32 minor_version; /* 2 minor version ... */ | ||
106 | __u32 patch_version; /* 3 patchlevel version ... */ | ||
107 | __u32 gvalid_words; /* 4 Number of used words in this section */ | ||
108 | __u32 set_uuid0; /* 5 Raid set identifier */ | ||
109 | __u32 ctime; /* 6 Creation time */ | ||
110 | __u32 level; /* 7 Raid personality */ | ||
111 | __u32 size; /* 8 Apparent size of each individual disk */ | ||
112 | __u32 nr_disks; /* 9 total disks in the raid set */ | ||
113 | __u32 raid_disks; /* 10 disks in a fully functional raid set */ | ||
114 | __u32 md_minor; /* 11 preferred MD minor device number */ | ||
115 | __u32 not_persistent; /* 12 does it have a persistent superblock */ | ||
116 | __u32 set_uuid1; /* 13 Raid set identifier #2 */ | ||
117 | __u32 set_uuid2; /* 14 Raid set identifier #3 */ | ||
118 | __u32 set_uuid3; /* 15 Raid set identifier #4 */ | ||
119 | __u32 gstate_creserved[MD_SB_GENERIC_CONSTANT_WORDS - 16]; | ||
120 | |||
121 | /* | ||
122 | * Generic state information | ||
123 | */ | ||
124 | __u32 utime; /* 0 Superblock update time */ | ||
125 | __u32 state; /* 1 State bits (clean, ...) */ | ||
126 | __u32 active_disks; /* 2 Number of currently active disks */ | ||
127 | __u32 working_disks; /* 3 Number of working disks */ | ||
128 | __u32 failed_disks; /* 4 Number of failed disks */ | ||
129 | __u32 spare_disks; /* 5 Number of spare disks */ | ||
130 | __u32 sb_csum; /* 6 checksum of the whole superblock */ | ||
131 | #ifdef __BIG_ENDIAN | ||
132 | __u32 events_hi; /* 7 high-order of superblock update count */ | ||
133 | __u32 events_lo; /* 8 low-order of superblock update count */ | ||
134 | __u32 cp_events_hi; /* 9 high-order of checkpoint update count */ | ||
135 | __u32 cp_events_lo; /* 10 low-order of checkpoint update count */ | ||
136 | #else | ||
137 | __u32 events_lo; /* 7 low-order of superblock update count */ | ||
138 | __u32 events_hi; /* 8 high-order of superblock update count */ | ||
139 | __u32 cp_events_lo; /* 9 low-order of checkpoint update count */ | ||
140 | __u32 cp_events_hi; /* 10 high-order of checkpoint update count */ | ||
141 | #endif | ||
142 | __u32 recovery_cp; /* 11 recovery checkpoint sector count */ | ||
143 | __u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 12]; | ||
144 | |||
145 | /* | ||
146 | * Personality information | ||
147 | */ | ||
148 | __u32 layout; /* 0 the array's physical layout */ | ||
149 | __u32 chunk_size; /* 1 chunk size in bytes */ | ||
150 | __u32 root_pv; /* 2 LV root PV */ | ||
151 | __u32 root_block; /* 3 LV root block */ | ||
152 | __u32 pstate_reserved[MD_SB_PERSONALITY_WORDS - 4]; | ||
153 | |||
154 | /* | ||
155 | * Disks information | ||
156 | */ | ||
157 | mdp_disk_t disks[MD_SB_DISKS]; | ||
158 | |||
159 | /* | ||
160 | * Reserved | ||
161 | */ | ||
162 | __u32 reserved[MD_SB_RESERVED_WORDS]; | ||
163 | |||
164 | /* | ||
165 | * Active descriptor | ||
166 | */ | ||
167 | mdp_disk_t this_disk; | ||
168 | |||
169 | } mdp_super_t; | ||
170 | |||
171 | static inline __u64 md_event(mdp_super_t *sb) { | ||
172 | __u64 ev = sb->events_hi; | ||
173 | return (ev<<32)| sb->events_lo; | ||
174 | } | ||
175 | |||
176 | /* | ||
177 | * The version-1 superblock : | ||
178 | * All numeric fields are little-endian. | ||
179 | * | ||
180 | * total size: 256 bytes plus 2 per device. | ||
181 | * 1K allows 384 devices. | ||
182 | */ | ||
183 | struct mdp_superblock_1 { | ||
184 | /* constant array information - 128 bytes */ | ||
185 | __u32 magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */ | ||
186 | __u32 major_version; /* 1 */ | ||
187 | __u32 feature_map; /* 0 for now */ | ||
188 | __u32 pad0; /* always set to 0 when writing */ | ||
189 | |||
190 | __u8 set_uuid[16]; /* user-space generated. */ | ||
191 | char set_name[32]; /* set and interpreted by user-space */ | ||
192 | |||
193 | __u64 ctime; /* lo 40 bits are seconds, top 24 are microseconds or 0*/ | ||
194 | __u32 level; /* -4 (multipath), -1 (linear), 0,1,4,5 */ | ||
195 | __u32 layout; /* only for raid5 currently */ | ||
196 | __u64 size; /* used size of component devices, in 512byte sectors */ | ||
197 | |||
198 | __u32 chunksize; /* in 512byte sectors */ | ||
199 | __u32 raid_disks; | ||
200 | __u8 pad1[128-96]; /* set to 0 when written */ | ||
201 | |||
202 | /* constant this-device information - 64 bytes */ | ||
203 | __u64 data_offset; /* sector start of data, often 0 */ | ||
204 | __u64 data_size; /* sectors in this device that can be used for data */ | ||
205 | __u64 super_offset; /* sector start of this superblock */ | ||
206 | __u64 recovery_offset;/* sectors before this offset (from data_offset) have been recovered */ | ||
207 | __u32 dev_number; /* permanent identifier of this device - not role in raid */ | ||
208 | __u32 cnt_corrected_read; /* number of read errors that were corrected by re-writing */ | ||
209 | __u8 device_uuid[16]; /* user-space setable, ignored by kernel */ | ||
210 | __u8 pad2[64-56]; /* set to 0 when writing */ | ||
211 | |||
212 | /* array state information - 64 bytes */ | ||
213 | __u64 utime; /* 40 bits second, 24 btes microseconds */ | ||
214 | __u64 events; /* incremented when superblock updated */ | ||
215 | __u64 resync_offset; /* data before this offset (from data_offset) known to be in sync */ | ||
216 | __u32 sb_csum; /* checksum upto devs[max_dev] */ | ||
217 | __u32 max_dev; /* size of devs[] array to consider */ | ||
218 | __u8 pad3[64-32]; /* set to 0 when writing */ | ||
219 | |||
220 | /* device state information. Indexed by dev_number. | ||
221 | * 2 bytes per device | ||
222 | * Note there are no per-device state flags. State information is rolled | ||
223 | * into the 'roles' value. If a device is spare or faulty, then it doesn't | ||
224 | * have a meaningful role. | ||
225 | */ | ||
226 | __u16 dev_roles[0]; /* role in array, or 0xffff for a spare, or 0xfffe for faulty */ | ||
227 | }; | ||
228 | |||
229 | #endif | ||
230 | |||