]>
Commit | Line | Data |
---|---|---|
e2be04c7 | 1 | /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ |
1da177e4 LT |
2 | /* |
3 | md_p.h : physical layout of Linux RAID devices | |
4 | Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman | |
5 | ||
6 | This program is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | You should have received a copy of the GNU General Public License | |
12 | (for example /usr/src/linux/COPYING); if not, write to the Free | |
13 | Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
14 | */ | |
15 | ||
16 | #ifndef _MD_P_H | |
17 | #define _MD_P_H | |
18 | ||
bcf74582 | 19 | #include <linux/types.h> |
c0f8bd14 | 20 | #include <asm/byteorder.h> |
bcf74582 | 21 | |
1da177e4 LT |
22 | /* |
23 | * RAID superblock. | |
24 | * | |
25 | * The RAID superblock maintains some statistics on each RAID configuration. | |
26 | * Each real device in the RAID set contains it near the end of the device. | |
27 | * Some of the ideas are copied from the ext2fs implementation. | |
28 | * | |
29 | * We currently use 4096 bytes as follows: | |
30 | * | |
31 | * word offset function | |
32 | * | |
33 | * 0 - 31 Constant generic RAID device information. | |
34 | * 32 - 63 Generic state information. | |
35 | * 64 - 127 Personality specific information. | |
36 | * 128 - 511 12 32-words descriptors of the disks in the raid set. | |
37 | * 512 - 911 Reserved. | |
38 | * 912 - 1023 Disk specific descriptor. | |
39 | */ | |
40 | ||
41 | /* | |
42 | * If x is the real device size in bytes, we return an apparent size of: | |
43 | * | |
44 | * y = (x & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES | |
45 | * | |
46 | * and place the 4kB superblock at offset y. | |
47 | */ | |
48 | #define MD_RESERVED_BYTES (64 * 1024) | |
49 | #define MD_RESERVED_SECTORS (MD_RESERVED_BYTES / 512) | |
1da177e4 LT |
50 | |
51 | #define MD_NEW_SIZE_SECTORS(x) ((x & ~(MD_RESERVED_SECTORS - 1)) - MD_RESERVED_SECTORS) | |
1da177e4 LT |
52 | |
53 | #define MD_SB_BYTES 4096 | |
54 | #define MD_SB_WORDS (MD_SB_BYTES / 4) | |
1da177e4 LT |
55 | #define MD_SB_SECTORS (MD_SB_BYTES / 512) |
56 | ||
57 | /* | |
58 | * The following are counted in 32-bit words | |
59 | */ | |
60 | #define MD_SB_GENERIC_OFFSET 0 | |
61 | #define MD_SB_PERSONALITY_OFFSET 64 | |
62 | #define MD_SB_DISKS_OFFSET 128 | |
63 | #define MD_SB_DESCRIPTOR_OFFSET 992 | |
64 | ||
65 | #define MD_SB_GENERIC_CONSTANT_WORDS 32 | |
66 | #define MD_SB_GENERIC_STATE_WORDS 32 | |
67 | #define MD_SB_GENERIC_WORDS (MD_SB_GENERIC_CONSTANT_WORDS + MD_SB_GENERIC_STATE_WORDS) | |
68 | #define MD_SB_PERSONALITY_WORDS 64 | |
69 | #define MD_SB_DESCRIPTOR_WORDS 32 | |
70 | #define MD_SB_DISKS 27 | |
71 | #define MD_SB_DISKS_WORDS (MD_SB_DISKS*MD_SB_DESCRIPTOR_WORDS) | |
72 | #define MD_SB_RESERVED_WORDS (1024 - MD_SB_GENERIC_WORDS - MD_SB_PERSONALITY_WORDS - MD_SB_DISKS_WORDS - MD_SB_DESCRIPTOR_WORDS) | |
73 | #define MD_SB_EQUAL_WORDS (MD_SB_GENERIC_WORDS + MD_SB_PERSONALITY_WORDS + MD_SB_DISKS_WORDS) | |
74 | ||
75 | /* | |
76 | * Device "operational" state bits | |
77 | */ | |
78 | #define MD_DISK_FAULTY 0 /* disk is faulty / operational */ | |
79 | #define MD_DISK_ACTIVE 1 /* disk is running or spare disk */ | |
80 | #define MD_DISK_SYNC 2 /* disk is in sync with the raid set */ | |
81 | #define MD_DISK_REMOVED 3 /* disk is in sync with the raid set */ | |
1aee41f6 GR |
82 | #define MD_DISK_CLUSTER_ADD 4 /* Initiate a disk add across the cluster |
83 | * For clustered enviroments only. | |
84 | */ | |
85 | #define MD_DISK_CANDIDATE 5 /* disk is added as spare (local) until confirmed | |
86 | * For clustered enviroments only. | |
87 | */ | |
688834e6 N |
88 | #define MD_DISK_FAILFAST 10 /* Send REQ_FAILFAST if there are multiple |
89 | * devices available - and don't try to | |
90 | * correct read errors. | |
91 | */ | |
1da177e4 | 92 | |
8ddf9efe N |
93 | #define MD_DISK_WRITEMOSTLY 9 /* disk is "write-mostly" is RAID1 config. |
94 | * read requests will only be sent here in | |
95 | * dire need | |
96 | */ | |
bac624f3 | 97 | #define MD_DISK_JOURNAL 18 /* disk is used as the write journal in RAID-5/6 */ |
8ddf9efe | 98 | |
c4d4c91b SL |
99 | #define MD_DISK_ROLE_SPARE 0xffff |
100 | #define MD_DISK_ROLE_FAULTY 0xfffe | |
bac624f3 | 101 | #define MD_DISK_ROLE_JOURNAL 0xfffd |
c4d4c91b SL |
102 | #define MD_DISK_ROLE_MAX 0xff00 /* max value of regular disk role */ |
103 | ||
1da177e4 LT |
104 | typedef struct mdp_device_descriptor_s { |
105 | __u32 number; /* 0 Device number in the entire set */ | |
106 | __u32 major; /* 1 Device major number */ | |
107 | __u32 minor; /* 2 Device minor number */ | |
108 | __u32 raid_disk; /* 3 The role of the device in the raid set */ | |
109 | __u32 state; /* 4 Operational state */ | |
110 | __u32 reserved[MD_SB_DESCRIPTOR_WORDS - 5]; | |
111 | } mdp_disk_t; | |
112 | ||
113 | #define MD_SB_MAGIC 0xa92b4efc | |
114 | ||
115 | /* | |
116 | * Superblock state bits | |
117 | */ | |
118 | #define MD_SB_CLEAN 0 | |
119 | #define MD_SB_ERRORS 1 | |
120 | ||
ca8895d9 | 121 | #define MD_SB_CLUSTERED 5 /* MD is clustered */ |
a654b9d8 | 122 | #define MD_SB_BITMAP_PRESENT 8 /* bitmap may be present nearby */ |
f6705578 N |
123 | |
124 | /* | |
125 | * Notes: | |
126 | * - if an array is being reshaped (restriped) in order to change the | |
127 | * the number of active devices in the array, 'raid_disks' will be | |
128 | * the larger of the old and new numbers. 'delta_disks' will | |
129 | * be the "new - old". So if +ve, raid_disks is the new value, and | |
130 | * "raid_disks-delta_disks" is the old. If -ve, raid_disks is the | |
131 | * old value and "raid_disks+delta_disks" is the new (smaller) value. | |
132 | */ | |
133 | ||
134 | ||
1da177e4 LT |
135 | typedef struct mdp_superblock_s { |
136 | /* | |
137 | * Constant generic information | |
138 | */ | |
139 | __u32 md_magic; /* 0 MD identifier */ | |
140 | __u32 major_version; /* 1 major version to which the set conforms */ | |
141 | __u32 minor_version; /* 2 minor version ... */ | |
142 | __u32 patch_version; /* 3 patchlevel version ... */ | |
143 | __u32 gvalid_words; /* 4 Number of used words in this section */ | |
144 | __u32 set_uuid0; /* 5 Raid set identifier */ | |
145 | __u32 ctime; /* 6 Creation time */ | |
146 | __u32 level; /* 7 Raid personality */ | |
147 | __u32 size; /* 8 Apparent size of each individual disk */ | |
148 | __u32 nr_disks; /* 9 total disks in the raid set */ | |
149 | __u32 raid_disks; /* 10 disks in a fully functional raid set */ | |
150 | __u32 md_minor; /* 11 preferred MD minor device number */ | |
151 | __u32 not_persistent; /* 12 does it have a persistent superblock */ | |
152 | __u32 set_uuid1; /* 13 Raid set identifier #2 */ | |
153 | __u32 set_uuid2; /* 14 Raid set identifier #3 */ | |
154 | __u32 set_uuid3; /* 15 Raid set identifier #4 */ | |
155 | __u32 gstate_creserved[MD_SB_GENERIC_CONSTANT_WORDS - 16]; | |
156 | ||
157 | /* | |
158 | * Generic state information | |
159 | */ | |
160 | __u32 utime; /* 0 Superblock update time */ | |
161 | __u32 state; /* 1 State bits (clean, ...) */ | |
162 | __u32 active_disks; /* 2 Number of currently active disks */ | |
163 | __u32 working_disks; /* 3 Number of working disks */ | |
164 | __u32 failed_disks; /* 4 Number of failed disks */ | |
165 | __u32 spare_disks; /* 5 Number of spare disks */ | |
166 | __u32 sb_csum; /* 6 checksum of the whole superblock */ | |
ca044f9a | 167 | #if defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN) |
1da177e4 LT |
168 | __u32 events_hi; /* 7 high-order of superblock update count */ |
169 | __u32 events_lo; /* 8 low-order of superblock update count */ | |
170 | __u32 cp_events_hi; /* 9 high-order of checkpoint update count */ | |
171 | __u32 cp_events_lo; /* 10 low-order of checkpoint update count */ | |
ca044f9a | 172 | #elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN) |
1da177e4 LT |
173 | __u32 events_lo; /* 7 low-order of superblock update count */ |
174 | __u32 events_hi; /* 8 high-order of superblock update count */ | |
175 | __u32 cp_events_lo; /* 9 low-order of checkpoint update count */ | |
176 | __u32 cp_events_hi; /* 10 high-order of checkpoint update count */ | |
ca044f9a DH |
177 | #else |
178 | #error unspecified endianness | |
1da177e4 LT |
179 | #endif |
180 | __u32 recovery_cp; /* 11 recovery checkpoint sector count */ | |
f6705578 N |
181 | /* There are only valid for minor_version > 90 */ |
182 | __u64 reshape_position; /* 12,13 next address in array-space for reshape */ | |
183 | __u32 new_level; /* 14 new level we are reshaping to */ | |
184 | __u32 delta_disks; /* 15 change in number of raid_disks */ | |
185 | __u32 new_layout; /* 16 new layout */ | |
186 | __u32 new_chunk; /* 17 new chunk size (bytes) */ | |
187 | __u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 18]; | |
1da177e4 LT |
188 | |
189 | /* | |
190 | * Personality information | |
191 | */ | |
192 | __u32 layout; /* 0 the array's physical layout */ | |
193 | __u32 chunk_size; /* 1 chunk size in bytes */ | |
194 | __u32 root_pv; /* 2 LV root PV */ | |
195 | __u32 root_block; /* 3 LV root block */ | |
196 | __u32 pstate_reserved[MD_SB_PERSONALITY_WORDS - 4]; | |
197 | ||
198 | /* | |
199 | * Disks information | |
200 | */ | |
201 | mdp_disk_t disks[MD_SB_DISKS]; | |
202 | ||
203 | /* | |
204 | * Reserved | |
205 | */ | |
206 | __u32 reserved[MD_SB_RESERVED_WORDS]; | |
207 | ||
208 | /* | |
209 | * Active descriptor | |
210 | */ | |
211 | mdp_disk_t this_disk; | |
212 | ||
213 | } mdp_super_t; | |
214 | ||
215 | static inline __u64 md_event(mdp_super_t *sb) { | |
216 | __u64 ev = sb->events_hi; | |
217 | return (ev<<32)| sb->events_lo; | |
218 | } | |
219 | ||
cd2ac932 CR |
220 | #define MD_SUPERBLOCK_1_TIME_SEC_MASK ((1ULL<<40) - 1) |
221 | ||
1da177e4 LT |
222 | /* |
223 | * The version-1 superblock : | |
224 | * All numeric fields are little-endian. | |
225 | * | |
226 | * total size: 256 bytes plus 2 per device. | |
227 | * 1K allows 384 devices. | |
228 | */ | |
229 | struct mdp_superblock_1 { | |
230 | /* constant array information - 128 bytes */ | |
1c05b4bc N |
231 | __le32 magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */ |
232 | __le32 major_version; /* 1 */ | |
233 | __le32 feature_map; /* bit 0 set if 'bitmap_offset' is meaningful */ | |
234 | __le32 pad0; /* always set to 0 when writing */ | |
1da177e4 LT |
235 | |
236 | __u8 set_uuid[16]; /* user-space generated. */ | |
237 | char set_name[32]; /* set and interpreted by user-space */ | |
238 | ||
1c05b4bc N |
239 | __le64 ctime; /* lo 40 bits are seconds, top 24 are microseconds or 0*/ |
240 | __le32 level; /* -4 (multipath), -1 (linear), 0,1,4,5 */ | |
241 | __le32 layout; /* only for raid5 and raid10 currently */ | |
242 | __le64 size; /* used size of component devices, in 512byte sectors */ | |
1da177e4 | 243 | |
1c05b4bc N |
244 | __le32 chunksize; /* in 512byte sectors */ |
245 | __le32 raid_disks; | |
ea0213e0 AP |
246 | union { |
247 | __le32 bitmap_offset; /* sectors after start of superblock that bitmap starts | |
248 | * NOTE: signed, so bitmap can be before superblock | |
249 | * only meaningful of feature_map[0] is set. | |
250 | */ | |
251 | ||
252 | /* only meaningful when feature_map[MD_FEATURE_PPL] is set */ | |
253 | struct { | |
254 | __le16 offset; /* sectors from start of superblock that ppl starts (signed) */ | |
255 | __le16 size; /* ppl size in sectors */ | |
256 | } ppl; | |
257 | }; | |
f6705578 N |
258 | |
259 | /* These are only valid with feature bit '4' */ | |
1c05b4bc N |
260 | __le32 new_level; /* new level we are reshaping to */ |
261 | __le64 reshape_position; /* next address in array-space for reshape */ | |
262 | __le32 delta_disks; /* change in number of raid_disks */ | |
263 | __le32 new_layout; /* new layout */ | |
cdc2ae6d | 264 | __le32 new_chunk; /* new chunk size (512byte sectors) */ |
c6563a8c N |
265 | __le32 new_offset; /* signed number to add to data_offset in new |
266 | * layout. 0 == no-change. This can be | |
267 | * different on each device in the array. | |
268 | */ | |
1da177e4 LT |
269 | |
270 | /* constant this-device information - 64 bytes */ | |
1c05b4bc N |
271 | __le64 data_offset; /* sector start of data, often 0 */ |
272 | __le64 data_size; /* sectors in this device that can be used for data */ | |
273 | __le64 super_offset; /* sector start of this superblock */ | |
3069aa8d SL |
274 | union { |
275 | __le64 recovery_offset;/* sectors before this offset (from data_offset) have been recovered */ | |
276 | __le64 journal_tail;/* journal tail of journal device (from data_offset) */ | |
277 | }; | |
1c05b4bc N |
278 | __le32 dev_number; /* permanent identifier of this device - not role in raid */ |
279 | __le32 cnt_corrected_read; /* number of read errors that were corrected by re-writing */ | |
1da177e4 | 280 | __u8 device_uuid[16]; /* user-space setable, ignored by kernel */ |
688834e6 | 281 | __u8 devflags; /* per-device flags. Only two defined...*/ |
8ddf9efe | 282 | #define WriteMostly1 1 /* mask for writemostly flag in above */ |
688834e6 | 283 | #define FailFast1 2 /* Should avoid retries and fixups and just fail */ |
2699b672 N |
284 | /* Bad block log. If there are any bad blocks the feature flag is set. |
285 | * If offset and size are non-zero, that space is reserved and available | |
286 | */ | |
287 | __u8 bblog_shift; /* shift from sectors to block size */ | |
288 | __le16 bblog_size; /* number of sectors reserved for list */ | |
289 | __le32 bblog_offset; /* sector offset from superblock to bblog, | |
290 | * signed - not unsigned */ | |
1da177e4 LT |
291 | |
292 | /* array state information - 64 bytes */ | |
2699b672 | 293 | __le64 utime; /* 40 bits second, 24 bits microseconds */ |
1c05b4bc N |
294 | __le64 events; /* incremented when superblock updated */ |
295 | __le64 resync_offset; /* data before this offset (from data_offset) known to be in sync */ | |
25985edc | 296 | __le32 sb_csum; /* checksum up to devs[max_dev] */ |
1c05b4bc | 297 | __le32 max_dev; /* size of devs[] array to consider */ |
1da177e4 LT |
298 | __u8 pad3[64-32]; /* set to 0 when writing */ |
299 | ||
300 | /* device state information. Indexed by dev_number. | |
301 | * 2 bytes per device | |
302 | * Note there are no per-device state flags. State information is rolled | |
303 | * into the 'roles' value. If a device is spare or faulty, then it doesn't | |
304 | * have a meaningful role. | |
305 | */ | |
1c05b4bc | 306 | __le16 dev_roles[0]; /* role in array, or 0xffff for a spare, or 0xfffe for faulty */ |
1da177e4 LT |
307 | }; |
308 | ||
71c0805c N |
309 | /* feature_map bits */ |
310 | #define MD_FEATURE_BITMAP_OFFSET 1 | |
5fd6c1dc N |
311 | #define MD_FEATURE_RECOVERY_OFFSET 2 /* recovery_offset is present and |
312 | * must be honoured | |
313 | */ | |
f6705578 | 314 | #define MD_FEATURE_RESHAPE_ACTIVE 4 |
2699b672 | 315 | #define MD_FEATURE_BAD_BLOCKS 8 /* badblock list is not empty */ |
2d78f8c4 N |
316 | #define MD_FEATURE_REPLACEMENT 16 /* This device is replacing an |
317 | * active device with same 'role'. | |
318 | * 'recovery_offset' is also set. | |
319 | */ | |
2c810cdd N |
320 | #define MD_FEATURE_RESHAPE_BACKWARDS 32 /* Reshape doesn't change number |
321 | * of devices, but is going | |
322 | * backwards anyway. | |
323 | */ | |
c6563a8c | 324 | #define MD_FEATURE_NEW_OFFSET 64 /* new_offset must be honoured */ |
f466722c N |
325 | #define MD_FEATURE_RECOVERY_BITMAP 128 /* recovery that is happening |
326 | * is guided by bitmap. | |
327 | */ | |
ddc08823 | 328 | #define MD_FEATURE_CLUSTERED 256 /* clustered MD */ |
bac624f3 | 329 | #define MD_FEATURE_JOURNAL 512 /* support write cache */ |
ea0213e0 | 330 | #define MD_FEATURE_PPL 1024 /* support PPL */ |
ddc08823 | 331 | #define MD_FEATURE_MULTIPLE_PPLS 2048 /* support for multiple PPLs */ |
43437ecd | 332 | #define MD_FEATURE_ALL (MD_FEATURE_BITMAP_OFFSET \ |
333 | |MD_FEATURE_RECOVERY_OFFSET \ | |
334 | |MD_FEATURE_RESHAPE_ACTIVE \ | |
335 | |MD_FEATURE_BAD_BLOCKS \ | |
2c810cdd | 336 | |MD_FEATURE_REPLACEMENT \ |
c6563a8c N |
337 | |MD_FEATURE_RESHAPE_BACKWARDS \ |
338 | |MD_FEATURE_NEW_OFFSET \ | |
f466722c | 339 | |MD_FEATURE_RECOVERY_BITMAP \ |
3c462c88 | 340 | |MD_FEATURE_CLUSTERED \ |
5c7e81c3 | 341 | |MD_FEATURE_JOURNAL \ |
ea0213e0 | 342 | |MD_FEATURE_PPL \ |
ddc08823 | 343 | |MD_FEATURE_MULTIPLE_PPLS \ |
c6563a8c | 344 | ) |
71c0805c | 345 | |
f6bed0ef SL |
346 | struct r5l_payload_header { |
347 | __le16 type; | |
348 | __le16 flags; | |
349 | } __attribute__ ((__packed__)); | |
350 | ||
351 | enum r5l_payload_type { | |
352 | R5LOG_PAYLOAD_DATA = 0, | |
353 | R5LOG_PAYLOAD_PARITY = 1, | |
354 | R5LOG_PAYLOAD_FLUSH = 2, | |
355 | }; | |
356 | ||
357 | struct r5l_payload_data_parity { | |
358 | struct r5l_payload_header header; | |
359 | __le32 size; /* sector. data/parity size. each 4k | |
360 | * has a checksum */ | |
361 | __le64 location; /* sector. For data, it's raid sector. For | |
362 | * parity, it's stripe sector */ | |
363 | __le32 checksum[]; | |
364 | } __attribute__ ((__packed__)); | |
365 | ||
366 | enum r5l_payload_data_parity_flag { | |
367 | R5LOG_PAYLOAD_FLAG_DISCARD = 1, /* payload is discard */ | |
368 | /* | |
369 | * RESHAPED/RESHAPING is only set when there is reshape activity. Note, | |
370 | * both data/parity of a stripe should have the same flag set | |
371 | * | |
372 | * RESHAPED: reshape is running, and this stripe finished reshape | |
373 | * RESHAPING: reshape is running, and this stripe isn't reshaped | |
374 | */ | |
375 | R5LOG_PAYLOAD_FLAG_RESHAPED = 2, | |
376 | R5LOG_PAYLOAD_FLAG_RESHAPING = 3, | |
377 | }; | |
378 | ||
379 | struct r5l_payload_flush { | |
380 | struct r5l_payload_header header; | |
381 | __le32 size; /* flush_stripes size, bytes */ | |
382 | __le64 flush_stripes[]; | |
383 | } __attribute__ ((__packed__)); | |
384 | ||
385 | enum r5l_payload_flush_flag { | |
386 | R5LOG_PAYLOAD_FLAG_FLUSH_STRIPE = 1, /* data represents whole stripe */ | |
387 | }; | |
388 | ||
389 | struct r5l_meta_block { | |
390 | __le32 magic; | |
391 | __le32 checksum; | |
392 | __u8 version; | |
393 | __u8 __zero_pading_1; | |
394 | __le16 __zero_pading_2; | |
395 | __le32 meta_size; /* whole size of the block */ | |
396 | ||
397 | __le64 seq; | |
398 | __le64 position; /* sector, start from rdev->data_offset, current position */ | |
399 | struct r5l_payload_header payloads[]; | |
400 | } __attribute__ ((__packed__)); | |
401 | ||
402 | #define R5LOG_VERSION 0x1 | |
403 | #define R5LOG_MAGIC 0x6433c509 | |
3418d036 AP |
404 | |
405 | struct ppl_header_entry { | |
406 | __le64 data_sector; /* raid sector of the new data */ | |
407 | __le32 pp_size; /* length of partial parity */ | |
408 | __le32 data_size; /* length of data */ | |
409 | __le32 parity_disk; /* member disk containing parity */ | |
410 | __le32 checksum; /* checksum of partial parity data for this | |
411 | * entry (~crc32c) */ | |
412 | } __attribute__ ((__packed__)); | |
413 | ||
414 | #define PPL_HEADER_SIZE 4096 | |
415 | #define PPL_HDR_RESERVED 512 | |
416 | #define PPL_HDR_ENTRY_SPACE \ | |
fc6d2a3c | 417 | (PPL_HEADER_SIZE - PPL_HDR_RESERVED - 4 * sizeof(__le32) - sizeof(__le64)) |
3418d036 AP |
418 | #define PPL_HDR_MAX_ENTRIES \ |
419 | (PPL_HDR_ENTRY_SPACE / sizeof(struct ppl_header_entry)) | |
420 | ||
421 | struct ppl_header { | |
422 | __u8 reserved[PPL_HDR_RESERVED];/* reserved space, fill with 0xff */ | |
423 | __le32 signature; /* signature (family number of volume) */ | |
424 | __le32 padding; /* zero pad */ | |
425 | __le64 generation; /* generation number of the header */ | |
426 | __le32 entries_count; /* number of entries in entry array */ | |
427 | __le32 checksum; /* checksum of the header (~crc32c) */ | |
428 | struct ppl_header_entry entries[PPL_HDR_MAX_ENTRIES]; | |
429 | } __attribute__ ((__packed__)); | |
430 | ||
f466722c | 431 | #endif |