2 * Copyright (c) 2011-2014 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@dragonflybsd.org>
6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
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16 * the documentation and/or other materials provided with the
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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36 #ifndef _VFS_HAMMER2_DISK_H_
37 #define _VFS_HAMMER2_DISK_H_
47 * The structures below represent the on-disk media structures for the HAMMER2
48 * filesystem. Note that all fields for on-disk structures are naturally
49 * aligned. The host endian format is typically used - compatibility is
50 * possible if the implementation detects reversed endian and adjusts accesses
53 * HAMMER2 primarily revolves around the directory topology: inodes,
54 * directory entries, and block tables. Block device buffer cache buffers
55 * are always 64KB. Logical file buffers are typically 16KB. All data
56 * references utilize 64-bit byte offsets.
58 * Free block management is handled independently using blocks reserved by
63 * The data at the end of a file or directory may be a fragment in order
64 * to optimize storage efficiency. The minimum fragment size is 1KB.
65 * Since allocations are in powers of 2 fragments must also be sized in
66 * powers of 2 (1024, 2048, ... 65536).
68 * For the moment the maximum allocation size is HAMMER2_PBUFSIZE (64K),
69 * which is 2^16. Larger extents may be supported in the future. Smaller
70 * fragments might be supported in the future (down to 64 bytes is possible),
71 * but probably will not be.
73 * A full indirect block use supports 1024 x 64-byte blockrefs in a 64KB
74 * buffer. Indirect blocks down to 1KB are supported to keep small
77 * A maximally sized file (2^64-1 bytes) requires 5 indirect block levels.
78 * The hammer2_blockset in the volume header or file inode has another 8
79 * entries, giving us 66+3 = 69 bits of address space. However, some bits
80 * are taken up by (potentially) requests for redundant copies. HAMMER2
81 * currently supports up to 8 copies, which brings the address space down
82 * to 66 bits and gives us 2 bits of leeway.
84 #define HAMMER2_ALLOC_MIN 1024 /* minimum allocation size */
85 #define HAMMER2_RADIX_MIN 10 /* minimum allocation size 2^N */
86 #define HAMMER2_ALLOC_MAX 65536 /* maximum allocation size */
87 #define HAMMER2_RADIX_MAX 16 /* maximum allocation size 2^N */
88 #define HAMMER2_RADIX_KEY 64 /* number of bits in key */
91 * MINALLOCSIZE - The minimum allocation size. This can be smaller
92 * or larger than the minimum physical IO size.
94 * NOTE: Should not be larger than 1K since inodes
97 * MINIOSIZE - The minimum IO size. This must be less than
98 * or equal to HAMMER2_LBUFSIZE.
100 * HAMMER2_LBUFSIZE - Nominal buffer size for I/O rollups.
102 * HAMMER2_PBUFSIZE - Topological block size used by files for all
103 * blocks except the block straddling EOF.
105 * HAMMER2_SEGSIZE - Allocation map segment size, typically 2MB
106 * (space represented by a level0 bitmap).
109 #define HAMMER2_SEGSIZE (1 << HAMMER2_FREEMAP_LEVEL0_RADIX)
110 #define HAMMER2_SEGRADIX HAMMER2_FREEMAP_LEVEL0_RADIX
112 #define HAMMER2_PBUFRADIX 16 /* physical buf (1<<16) bytes */
113 #define HAMMER2_PBUFSIZE 65536
114 #define HAMMER2_LBUFRADIX 14 /* logical buf (1<<14) bytes */
115 #define HAMMER2_LBUFSIZE 16384
118 * Generally speaking we want to use 16K and 64K I/Os
120 #define HAMMER2_MINIORADIX HAMMER2_LBUFRADIX
121 #define HAMMER2_MINIOSIZE HAMMER2_LBUFSIZE
123 #define HAMMER2_IND_BYTES_MIN HAMMER2_LBUFSIZE
124 #define HAMMER2_IND_BYTES_MAX HAMMER2_PBUFSIZE
125 #define HAMMER2_IND_COUNT_MIN (HAMMER2_IND_BYTES_MIN / \
126 sizeof(hammer2_blockref_t))
127 #define HAMMER2_IND_COUNT_MAX (HAMMER2_IND_BYTES_MAX / \
128 sizeof(hammer2_blockref_t))
131 * In HAMMER2, arrays of blockrefs are fully set-associative, meaning that
132 * any element can occur at any index and holes can be anywhere. As a
133 * future optimization we will be able to flag that such arrays are sorted
134 * and thus optimize lookups, but for now we don't.
136 * Inodes embed either 512 bytes of direct data or an array of 8 blockrefs,
137 * resulting in highly efficient storage for files <= 512 bytes and for files
138 * <= 512KB. Up to 8 directory entries can be referenced from a directory
139 * without requiring an indirect block.
141 * Indirect blocks are typically either 4KB (64 blockrefs / ~4MB represented),
142 * or 64KB (1024 blockrefs / ~64MB represented).
144 #define HAMMER2_SET_COUNT 8 /* direct entries */
145 #define HAMMER2_SET_RADIX 3
146 #define HAMMER2_EMBEDDED_BYTES 512 /* inode blockset/dd size */
147 #define HAMMER2_EMBEDDED_RADIX 9
149 #define HAMMER2_PBUFMASK (HAMMER2_PBUFSIZE - 1)
150 #define HAMMER2_LBUFMASK (HAMMER2_LBUFSIZE - 1)
151 #define HAMMER2_SEGMASK (HAMMER2_SEGSIZE - 1)
153 #define HAMMER2_LBUFMASK64 ((hammer2_off_t)HAMMER2_LBUFMASK)
154 #define HAMMER2_PBUFSIZE64 ((hammer2_off_t)HAMMER2_PBUFSIZE)
155 #define HAMMER2_PBUFMASK64 ((hammer2_off_t)HAMMER2_PBUFMASK)
156 #define HAMMER2_SEGSIZE64 ((hammer2_off_t)HAMMER2_SEGSIZE)
157 #define HAMMER2_SEGMASK64 ((hammer2_off_t)HAMMER2_SEGMASK)
159 #define HAMMER2_UUID_STRING "5cbb9ad1-862d-11dc-a94d-01301bb8a9f5"
162 * A HAMMER2 filesystem is always sized in multiples of 8MB.
164 * A 4MB segment is reserved at the beginning of each 2GB zone. This segment
165 * contains the volume header (or backup volume header), the free block
166 * table, and possibly other information in the future.
168 * 4MB = 64 x 64K blocks. Each 4MB segment is broken down as follows:
170 * +-----------------------+
171 * | Volume Hdr | block 0 volume header & alternates
172 * +-----------------------+ (first four zones only)
173 * | FreeBlk Section A | block 1-4
174 * +-----------------------+
175 * | FreeBlk Section B | block 5-8
176 * +-----------------------+
177 * | FreeBlk Section C | block 9-12
178 * +-----------------------+
179 * | FreeBlk Section D | block 13-16
180 * +-----------------------+
184 * +-----------------------+
186 * The first few 2GB zones contain volume headers and volume header backups.
187 * After that the volume header block# is reserved for future use. Similarly,
188 * there are many blocks related to various Freemap levels which are not
189 * used in every segment and those are also reserved for future use.
191 * Freemap (see the FREEMAP document)
193 * The freemap utilizes blocks #1-16 in 8 sets of 4 blocks. Each block in
194 * a set represents a level of depth in the freemap topology. Eight sets
195 * exist to prevent live updates from disturbing the state of the freemap
196 * were a crash/reboot to occur. That is, a live update is not committed
197 * until the update's flush reaches the volume root. There are FOUR volume
198 * roots representing the last four synchronization points, so the freemap
199 * must be consistent no matter which volume root is chosen by the mount
202 * Each freemap set is 4 x 64K blocks and represents the 2GB, 2TB, 2PB,
203 * and 2EB indirect map. The volume header itself has a set of 8 freemap
204 * blockrefs representing another 3 bits, giving us a total 64 bits of
205 * representable address space.
207 * The Level 0 64KB block represents 2GB of storage represented by
208 * (64 x struct hammer2_bmap_data). Each structure represents 2MB of storage
209 * and has a 256 bit bitmap, using 2 bits to represent a 16KB chunk of
210 * storage. These 2 bits represent the following states:
213 * 01 (reserved) (Possibly partially allocated)
217 * One important thing to note here is that the freemap resolution is 16KB,
218 * but the minimum storage allocation size is 1KB. The hammer2 vfs keeps
219 * track of sub-allocations in memory, which means that on a unmount or reboot
220 * the entire 16KB of a partially allocated block will be considered fully
221 * allocated. It is possible for fragmentation to build up over time, but
222 * defragmentation is fairly easy to accomplish since all modifications
223 * allocate a new block.
225 * The Second thing to note is that due to the way snapshots and inode
226 * replication works, deleting a file cannot immediately free the related
227 * space. Furthermore, deletions often do not bother to traverse the
228 * block subhierarchy being deleted. And to go even further, whole
229 * sub-directory trees can be deleted simply by deleting the directory inode
230 * at the top. So even though we have a symbol to represent a 'possibly free'
231 * block (binary 10), only the bulk free scanning code can actually use it.
232 * Normal 'rm's or other deletions do not.
234 * WARNING! ZONE_SEG and VOLUME_ALIGN must be a multiple of 1<<LEVEL0_RADIX
235 * (i.e. a multiple of 2MB). VOLUME_ALIGN must be >= ZONE_SEG.
239 * (1) Modifications to freemap blocks 'allocate' a new copy (aka use a block
240 * from the next set). The new copy is reused until a flush occurs at
241 * which point the next modification will then rotate to the next set.
243 * (2) A total of 10 freemap sets is required.
245 * - 8 sets - 2 sets per volume header backup x 4 volume header backups
246 * - 2 sets used as backing store for the bulk freemap scan.
247 * - The freemap recovery scan which runs on-mount just uses the inactive
248 * set for whichever volume header was selected by the mount code.
251 #define HAMMER2_VOLUME_ALIGN (8 * 1024 * 1024)
252 #define HAMMER2_VOLUME_ALIGN64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGN)
253 #define HAMMER2_VOLUME_ALIGNMASK (HAMMER2_VOLUME_ALIGN - 1)
254 #define HAMMER2_VOLUME_ALIGNMASK64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGNMASK)
256 #define HAMMER2_NEWFS_ALIGN (HAMMER2_VOLUME_ALIGN)
257 #define HAMMER2_NEWFS_ALIGN64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGN)
258 #define HAMMER2_NEWFS_ALIGNMASK (HAMMER2_VOLUME_ALIGN - 1)
259 #define HAMMER2_NEWFS_ALIGNMASK64 ((hammer2_off_t)HAMMER2_NEWFS_ALIGNMASK)
261 #define HAMMER2_ZONE_BYTES64 (2LLU * 1024 * 1024 * 1024)
262 #define HAMMER2_ZONE_MASK64 (HAMMER2_ZONE_BYTES64 - 1)
263 #define HAMMER2_ZONE_SEG (4 * 1024 * 1024)
264 #define HAMMER2_ZONE_SEG64 ((hammer2_off_t)HAMMER2_ZONE_SEG)
265 #define HAMMER2_ZONE_BLOCKS_SEG (HAMMER2_ZONE_SEG / HAMMER2_PBUFSIZE)
267 #define HAMMER2_ZONE_VOLHDR 0 /* volume header or backup */
268 #define HAMMER2_ZONE_FREEMAP_00 1 /* normal freemap rotation */
269 #define HAMMER2_ZONE_FREEMAP_01 5 /* normal freemap rotation */
270 #define HAMMER2_ZONE_FREEMAP_02 9 /* normal freemap rotation */
271 #define HAMMER2_ZONE_FREEMAP_03 13 /* normal freemap rotation */
272 #define HAMMER2_ZONE_FREEMAP_04 17 /* normal freemap rotation */
273 #define HAMMER2_ZONE_FREEMAP_05 21 /* normal freemap rotation */
274 #define HAMMER2_ZONE_FREEMAP_06 25 /* normal freemap rotation */
275 #define HAMMER2_ZONE_FREEMAP_07 29 /* normal freemap rotation */
276 #define HAMMER2_ZONE_FREEMAP_END 33 /* (non-inclusive) */
278 #define HAMMER2_ZONE_UNUSED33 33
279 #define HAMMER2_ZONE_UNUSED34 34
280 #define HAMMER2_ZONE_UNUSED35 35
281 #define HAMMER2_ZONE_UNUSED36 36
282 #define HAMMER2_ZONE_UNUSED37 37
283 #define HAMMER2_ZONE_UNUSED38 38
284 #define HAMMER2_ZONE_UNUSED39 39
285 #define HAMMER2_ZONE_UNUSED40 40
286 #define HAMMER2_ZONE_UNUSED41 41
287 #define HAMMER2_ZONE_UNUSED42 42
288 #define HAMMER2_ZONE_UNUSED43 43
289 #define HAMMER2_ZONE_UNUSED44 44
290 #define HAMMER2_ZONE_UNUSED45 45
291 #define HAMMER2_ZONE_UNUSED46 46
292 #define HAMMER2_ZONE_UNUSED47 47
293 #define HAMMER2_ZONE_UNUSED48 48
294 #define HAMMER2_ZONE_UNUSED49 49
295 #define HAMMER2_ZONE_UNUSED50 50
296 #define HAMMER2_ZONE_UNUSED51 51
297 #define HAMMER2_ZONE_UNUSED52 52
298 #define HAMMER2_ZONE_UNUSED53 53
299 #define HAMMER2_ZONE_UNUSED54 54
300 #define HAMMER2_ZONE_UNUSED55 55
301 #define HAMMER2_ZONE_UNUSED56 56
302 #define HAMMER2_ZONE_UNUSED57 57
303 #define HAMMER2_ZONE_UNUSED58 58
304 #define HAMMER2_ZONE_UNUSED59 59
305 #define HAMMER2_ZONE_UNUSED60 60
306 #define HAMMER2_ZONE_UNUSED61 61
307 #define HAMMER2_ZONE_UNUSED62 62
308 #define HAMMER2_ZONE_UNUSED63 63
309 #define HAMMER2_ZONE_END 64 /* non-inclusive */
311 #define HAMMER2_NFREEMAPS 8 /* FREEMAP_00 - FREEMAP_07 */
313 /* relative to FREEMAP_x */
314 #define HAMMER2_ZONEFM_LEVEL1 0 /* 2GB leafmap */
315 #define HAMMER2_ZONEFM_LEVEL2 1 /* 2TB indmap */
316 #define HAMMER2_ZONEFM_LEVEL3 2 /* 2PB indmap */
317 #define HAMMER2_ZONEFM_LEVEL4 3 /* 2EB indmap */
318 /* LEVEL5 is a set of 8 blockrefs in the volume header 16EB */
321 * Freemap radix. Note that the LEVEL 1 blockref points to a 64KB freemap
322 * block containing 1024 x LEVEL0 hammer2_bmap_data structures. LEVEL 0
323 * represents one structure.
325 #define HAMMER2_FREEMAP_LEVEL5_RADIX 64 /* 16EB (end) */
326 #define HAMMER2_FREEMAP_LEVEL4_RADIX 61 /* 2EB */
327 #define HAMMER2_FREEMAP_LEVEL3_RADIX 51 /* 2PB */
328 #define HAMMER2_FREEMAP_LEVEL2_RADIX 41 /* 2TB */
329 #define HAMMER2_FREEMAP_LEVEL1_RADIX 31 /* 2GB */
330 #define HAMMER2_FREEMAP_LEVEL0_RADIX 21 /* 2MB (entry in l-1 leaf) */
332 #define HAMMER2_FREEMAP_LEVELN_PSIZE 65536 /* physical bytes */
334 #define HAMMER2_FREEMAP_LEVEL4_SIZE ((hammer2_off_t)1 << \
335 HAMMER2_FREEMAP_LEVEL4_RADIX)
336 #define HAMMER2_FREEMAP_LEVEL3_SIZE ((hammer2_off_t)1 << \
337 HAMMER2_FREEMAP_LEVEL3_RADIX)
338 #define HAMMER2_FREEMAP_LEVEL2_SIZE ((hammer2_off_t)1 << \
339 HAMMER2_FREEMAP_LEVEL2_RADIX)
340 #define HAMMER2_FREEMAP_LEVEL1_SIZE ((hammer2_off_t)1 << \
341 HAMMER2_FREEMAP_LEVEL1_RADIX)
342 #define HAMMER2_FREEMAP_LEVEL0_SIZE ((hammer2_off_t)1 << \
343 HAMMER2_FREEMAP_LEVEL0_RADIX)
345 #define HAMMER2_FREEMAP_LEVEL4_MASK (HAMMER2_FREEMAP_LEVEL4_SIZE - 1)
346 #define HAMMER2_FREEMAP_LEVEL3_MASK (HAMMER2_FREEMAP_LEVEL3_SIZE - 1)
347 #define HAMMER2_FREEMAP_LEVEL2_MASK (HAMMER2_FREEMAP_LEVEL2_SIZE - 1)
348 #define HAMMER2_FREEMAP_LEVEL1_MASK (HAMMER2_FREEMAP_LEVEL1_SIZE - 1)
349 #define HAMMER2_FREEMAP_LEVEL0_MASK (HAMMER2_FREEMAP_LEVEL0_SIZE - 1)
351 #define HAMMER2_FREEMAP_COUNT (int)(HAMMER2_FREEMAP_LEVELN_PSIZE / \
352 sizeof(hammer2_bmap_data_t))
353 #define HAMMER2_FREEMAP_BLOCK_RADIX 14
354 #define HAMMER2_FREEMAP_BLOCK_SIZE (1 << HAMMER2_FREEMAP_BLOCK_RADIX)
355 #define HAMMER2_FREEMAP_BLOCK_MASK (HAMMER2_FREEMAP_BLOCK_SIZE - 1)
358 * bitmap[] structure. 2 bits per HAMMER2_FREEMAP_BLOCK_SIZE. Each bitmap[]
359 * element is 32 bits and thus represents 16 blocks (radix 4).
361 #define HAMMER2_BMAP_INDEX_RADIX 4
362 #define HAMMER2_BMAP_INDEX_SIZE (HAMMER2_FREEMAP_BLOCK_SIZE * 16)
363 #define HAMMER2_BMAP_INDEX_MASK (HAMMER2_BMAP_INDEX_SIZE - 1)
366 * Two linear areas can be reserved after the initial 2MB segment in the base
367 * zone (the one starting at offset 0). These areas are NOT managed by the
368 * block allocator and do not fall under HAMMER2 crc checking rules based
369 * at the volume header (but can be self-CRCd internally, depending).
371 #define HAMMER2_BOOT_MIN_BYTES HAMMER2_VOLUME_ALIGN
372 #define HAMMER2_BOOT_NOM_BYTES (64*1024*1024)
373 #define HAMMER2_BOOT_MAX_BYTES (256*1024*1024)
375 #define HAMMER2_REDO_MIN_BYTES HAMMER2_VOLUME_ALIGN
376 #define HAMMER2_REDO_NOM_BYTES (256*1024*1024)
377 #define HAMMER2_REDO_MAX_BYTES (1024*1024*1024)
380 * Most HAMMER2 types are implemented as unsigned 64-bit integers.
381 * Transaction ids are monotonic.
383 * We utilize 32-bit iSCSI CRCs.
385 typedef uint64_t hammer2_tid_t;
386 typedef uint64_t hammer2_off_t;
387 typedef uint64_t hammer2_key_t;
388 typedef uint32_t hammer2_crc32_t;
391 * Miscellanious ranges (all are unsigned).
393 #define HAMMER2_TID_MIN 1ULL
394 #define HAMMER2_TID_MAX 0xFFFFFFFFFFFFFFFFULL
395 #define HAMMER2_KEY_MIN 0ULL
396 #define HAMMER2_KEY_MAX 0xFFFFFFFFFFFFFFFFULL
397 #define HAMMER2_OFFSET_MIN 0ULL
398 #define HAMMER2_OFFSET_MAX 0xFFFFFFFFFFFFFFFFULL
401 * HAMMER2 data offset special cases and masking.
403 * All HAMMER2 data offsets have to be broken down into a 64K buffer base
404 * offset (HAMMER2_OFF_MASK_HI) and a 64K buffer index (HAMMER2_OFF_MASK_LO).
406 * Indexes into physical buffers are always 64-byte aligned. The low 6 bits
407 * of the data offset field specifies how large the data chunk being pointed
408 * to as a power of 2. The theoretical minimum radix is thus 6 (The space
409 * needed in the low bits of the data offset field). However, the practical
410 * minimum allocation chunk size is 1KB (a radix of 10), so HAMMER2 sets
411 * HAMMER2_RADIX_MIN to 10. The maximum radix is currently 16 (64KB), but
412 * we fully intend to support larger extents in the future.
414 #define HAMMER2_OFF_BAD ((hammer2_off_t)-1)
415 #define HAMMER2_OFF_MASK 0xFFFFFFFFFFFFFFC0ULL
416 #define HAMMER2_OFF_MASK_LO (HAMMER2_OFF_MASK & HAMMER2_PBUFMASK64)
417 #define HAMMER2_OFF_MASK_HI (~HAMMER2_PBUFMASK64)
418 #define HAMMER2_OFF_MASK_RADIX 0x000000000000003FULL
419 #define HAMMER2_MAX_COPIES 6
422 * HAMMER2 directory support and pre-defined keys
424 #define HAMMER2_DIRHASH_VISIBLE 0x8000000000000000ULL
425 #define HAMMER2_DIRHASH_USERMSK 0x7FFFFFFFFFFFFFFFULL
426 #define HAMMER2_DIRHASH_LOMASK 0x0000000000007FFFULL
427 #define HAMMER2_DIRHASH_HIMASK 0xFFFFFFFFFFFF0000ULL
428 #define HAMMER2_DIRHASH_FORCED 0x0000000000008000ULL /* bit forced on */
430 #define HAMMER2_SROOT_KEY 0x0000000000000000ULL /* volume to sroot */
432 /************************************************************************
434 ************************************************************************
437 * All HAMMER2 directories directly under the super-root on your local
438 * media can be mounted separately, even if they share the same physical
441 * When you do a HAMMER2 mount you are effectively tying into a HAMMER2
442 * cluster via local media. The local media does not have to participate
443 * in the cluster, other than to provide the hammer2_volconf[] array and
444 * root inode for the mount.
446 * This is important: The mount device path you specify serves to bootstrap
447 * your entry into the cluster, but your mount will make active connections
448 * to ALL copy elements in the hammer2_volconf[] array which match the
449 * PFSID of the directory in the super-root that you specified. The local
450 * media path does not have to be mentioned in this array but becomes part
451 * of the cluster based on its type and access rights. ALL ELEMENTS ARE
452 * TREATED ACCORDING TO TYPE NO MATTER WHICH ONE YOU MOUNT FROM.
454 * The actual cluster may be far larger than the elements you list in the
455 * hammer2_volconf[] array. You list only the elements you wish to
456 * directly connect to and you are able to access the rest of the cluster
457 * indirectly through those connections.
459 * WARNING! This structure must be exactly 128 bytes long for its config
460 * array to fit in the volume header.
462 struct hammer2_volconf {
463 uint8_t copyid; /* 00 copyid 0-255 (must match slot) */
464 uint8_t inprog; /* 01 operation in progress, or 0 */
465 uint8_t chain_to; /* 02 operation chaining to, or 0 */
466 uint8_t chain_from; /* 03 operation chaining from, or 0 */
467 uint16_t flags; /* 04-05 flags field */
468 uint8_t error; /* 06 last operational error */
469 uint8_t priority; /* 07 priority and round-robin flag */
470 uint8_t remote_pfs_type;/* 08 probed direct remote PFS type */
471 uint8_t reserved08[23]; /* 09-1F */
472 uuid_t pfs_clid; /* 20-2F copy target must match this uuid */
473 uint8_t label[16]; /* 30-3F import/export label */
474 uint8_t path[64]; /* 40-7F target specification string or key */
477 typedef struct hammer2_volconf hammer2_volconf_t;
479 #define DMSG_VOLF_ENABLED 0x0001
480 #define DMSG_VOLF_INPROG 0x0002
481 #define DMSG_VOLF_CONN_RR 0x80 /* round-robin at same priority */
482 #define DMSG_VOLF_CONN_EF 0x40 /* media errors flagged */
483 #define DMSG_VOLF_CONN_PRI 0x0F /* select priority 0-15 (15=best) */
485 struct dmsg_lnk_hammer2_volconf {
487 hammer2_volconf_t copy; /* copy spec */
491 int64_t reserved02[32];
494 typedef struct dmsg_lnk_hammer2_volconf dmsg_lnk_hammer2_volconf_t;
496 #define DMSG_LNK_HAMMER2_VOLCONF DMSG_LNK(DMSG_LNK_CMD_HAMMER2_VOLCONF, \
497 dmsg_lnk_hammer2_volconf)
499 #define H2_LNK_VOLCONF(msg) ((dmsg_lnk_hammer2_volconf_t *)(msg)->any.buf)
502 * The media block reference structure. This forms the core of the HAMMER2
503 * media topology recursion. This 64-byte data structure is embedded in the
504 * volume header, in inodes (which are also directory entries), and in
507 * A blockref references a single media item, which typically can be a
508 * directory entry (aka inode), indirect block, or data block.
510 * The primary feature a blockref represents is the ability to validate
511 * the entire tree underneath it via its check code. Any modification to
512 * anything propagates up the blockref tree all the way to the root, replacing
513 * the related blocks. Propagations can shortcut to the volume root to
514 * implement the 'fast syncing' feature but this only delays the eventual
517 * The check code can be a simple 32-bit iscsi code, a 64-bit crc,
518 * or as complex as a 192 bit cryptographic hash. 192 bits is the maximum
519 * supported check code size, which is not sufficient for unverified dedup
520 * UNLESS one doesn't mind once-in-a-blue-moon data corruption (such as when
521 * farming web data). HAMMER2 has an unverified dedup feature for just this
526 * NOTE: The range of keys represented by the blockref is (key) to
527 * ((key) + (1LL << keybits) - 1). HAMMER2 usually populates
528 * blocks bottom-up, inserting a new root when radix expansion
532 * FUTURE BLOCKREF EXPANSION
534 * In order to implement a 256-bit content addressable index we want to
535 * have a 256-bit key which essentially represents the cryptographic hash.
536 * (so, 64-bit key + 192-bit crypto-hash or 256-bit key-is-the-hash +
537 * 32-bit consistency check for indirect block layers).
539 * THIS IS POSSIBLE in a 64-byte blockref structure. Of course, any number
540 * of bits can be represented by sizing the blockref. For the purposes of
541 * HAMMER2 though my limit is 256 bits. Not only that, but it will be an
542 * optimal construction because H2 already uses a variably-sized radix to
543 * pack the blockrefs at each level. A 256-bit mechanic would allow us
544 * to implement a content-addressable index.
546 struct hammer2_blockref { /* MUST BE EXACTLY 64 BYTES */
547 uint8_t type; /* type of underlying item */
548 uint8_t methods; /* check method & compression method */
549 uint8_t copyid; /* specify which copy this is */
550 uint8_t keybits; /* #of keybits masked off 0=leaf */
551 uint8_t vradix; /* virtual data/meta-data size */
552 uint8_t flags; /* blockref flags */
555 hammer2_key_t key; /* key specification */
556 hammer2_tid_t mirror_tid; /* propagate for mirror scan */
557 hammer2_tid_t modify_tid; /* modifications sans propagation */
558 hammer2_off_t data_off; /* low 6 bits is phys size (radix)*/
559 union { /* check info */
574 * Freemap hints are embedded in addition to the icrc32.
576 * bigmask - Radixes available for allocation (0-31).
577 * Heuristical (may be permissive but not
578 * restrictive). Typically only radix values
579 * 10-16 are used (i.e. (1<<10) through (1<<16)).
581 * avail - Total available space remaining, in bytes
585 uint32_t bigmask; /* available radixes */
586 uint64_t avail; /* total available bytes */
587 uint64_t unused; /* unused must be 0 */
592 typedef struct hammer2_blockref hammer2_blockref_t;
594 #define HAMMER2_BLOCKREF_BYTES 64 /* blockref struct in bytes */
597 * On-media and off-media blockref types.
599 * types >= 128 are pseudo values that should never be present on-media.
601 #define HAMMER2_BREF_TYPE_EMPTY 0
602 #define HAMMER2_BREF_TYPE_INODE 1
603 #define HAMMER2_BREF_TYPE_INDIRECT 2
604 #define HAMMER2_BREF_TYPE_DATA 3
605 #define HAMMER2_BREF_TYPE_UNUSED04 4
606 #define HAMMER2_BREF_TYPE_FREEMAP_NODE 5
607 #define HAMMER2_BREF_TYPE_FREEMAP_LEAF 6
608 #define HAMMER2_BREF_TYPE_FREEMAP 254 /* pseudo-type */
609 #define HAMMER2_BREF_TYPE_VOLUME 255 /* pseudo-type */
611 #define HAMMER2_BREF_FLAG_PFSROOT 0x01 /* see also related opflag */
612 #define HAMMER2_BREF_FLAG_ZERO 0x02
615 * Encode/decode check mode and compression mode for
616 * bref.methods. The compression level is not encoded in
619 #define HAMMER2_ENC_CHECK(n) (((n) & 15) << 4)
620 #define HAMMER2_DEC_CHECK(n) (((n) >> 4) & 15)
621 #define HAMMER2_ENC_COMP(n) ((n) & 15)
622 #define HAMMER2_DEC_COMP(n) ((n) & 15)
624 #define HAMMER2_CHECK_NONE 0
625 #define HAMMER2_CHECK_DISABLED 1
626 #define HAMMER2_CHECK_ISCSI32 2
627 #define HAMMER2_CHECK_CRC64 3
628 #define HAMMER2_CHECK_SHA192 4
629 #define HAMMER2_CHECK_FREEMAP 5
631 /* user-specifiable check modes only */
632 #define HAMMER2_CHECK_STRINGS { "none", "disabled", "crc32", \
634 #define HAMMER2_CHECK_STRINGS_COUNT 5
637 * Encode/decode check or compression algorithm request in
638 * ipdata->check_algo and ipdata->comp_algo.
640 #define HAMMER2_ENC_ALGO(n) (n)
641 #define HAMMER2_DEC_ALGO(n) ((n) & 15)
642 #define HAMMER2_ENC_LEVEL(n) ((n) << 4)
643 #define HAMMER2_DEC_LEVEL(n) (((n) >> 4) & 15)
645 #define HAMMER2_COMP_NONE 0
646 #define HAMMER2_COMP_AUTOZERO 1
647 #define HAMMER2_COMP_LZ4 2
648 #define HAMMER2_COMP_ZLIB 3
650 #define HAMMER2_COMP_NEWFS_DEFAULT HAMMER2_COMP_LZ4
651 #define HAMMER2_COMP_STRINGS { "none", "autozero", "lz4", "zlib" }
652 #define HAMMER2_COMP_STRINGS_COUNT 4
656 * HAMMER2 block references are collected into sets of 8 blockrefs. These
657 * sets are fully associative, meaning the elements making up a set are
658 * not sorted in any way and may contain duplicate entries, holes, or
659 * entries which shortcut multiple levels of indirection. Sets are used
662 * (1) When redundancy is desired a set may contain several duplicate
663 * entries pointing to different copies of the same data. Up to 8 copies
664 * are supported but the set structure becomes a bit inefficient once
667 * (2) The blockrefs in a set can shortcut multiple levels of indirections
668 * within the bounds imposed by the parent of set.
670 * When a set fills up another level of indirection is inserted, moving
671 * some or all of the set's contents into indirect blocks placed under the
672 * set. This is a top-down approach in that indirect blocks are not created
673 * until the set actually becomes full (that is, the entries in the set can
674 * shortcut the indirect blocks when the set is not full). Depending on how
675 * things are filled multiple indirect blocks will eventually be created.
677 * Indirect blocks are typically 4KB (64 entres) or 64KB (1024 entries) and
678 * are also treated as fully set-associative.
680 struct hammer2_blockset {
681 hammer2_blockref_t blockref[HAMMER2_SET_COUNT];
684 typedef struct hammer2_blockset hammer2_blockset_t;
687 * Catch programmer snafus
689 #if (1 << HAMMER2_SET_RADIX) != HAMMER2_SET_COUNT
690 #error "hammer2 direct radix is incorrect"
692 #if (1 << HAMMER2_PBUFRADIX) != HAMMER2_PBUFSIZE
693 #error "HAMMER2_PBUFRADIX and HAMMER2_PBUFSIZE are inconsistent"
695 #if (1 << HAMMER2_RADIX_MIN) != HAMMER2_ALLOC_MIN
696 #error "HAMMER2_RADIX_MIN and HAMMER2_ALLOC_MIN are inconsistent"
700 * hammer2_bmap_data - A freemap entry in the LEVEL1 block.
702 * Each 64-byte entry contains the bitmap and meta-data required to manage
703 * a LEVEL0 (2MB) block of storage. The storage is managed in 128 x 16KB
704 * chunks. Smaller allocation granularity is supported via a linear iterator
705 * and/or must otherwise be tracked in ram.
707 * (data structure must be 64 bytes exactly)
709 * linear - A BYTE linear allocation offset used for sub-16KB allocations
710 * only. May contain values between 0 and 2MB. Must be ignored
711 * if 16KB-aligned (i.e. force bitmap scan), otherwise may be
712 * used to sub-allocate within the 16KB block (which is already
713 * marked as allocated in the bitmap).
715 * Sub-allocations need only be 1KB-aligned and do not have to be
716 * size-aligned, and 16KB or larger allocations do not update this
717 * field, resulting in pretty good packing.
719 * Please note that file data granularity may be limited by
720 * other issues such as buffer cache direct-mapping and the
721 * desire to support sector sizes up to 16KB (so H2 only issues
722 * I/O's in multiples of 16KB anyway).
724 * class - Clustering class. Cleared to 0 only if the entire leaf becomes
725 * free. Used to cluster device buffers so all elements must have
726 * the same device block size, but may mix logical sizes.
728 * Typically integrated with the blockref type in the upper 8 bits
729 * to localize inodes and indrect blocks, improving bulk free scans
730 * and directory scans.
732 * bitmap - Two bits per 16KB allocation block arranged in arrays of
733 * 32-bit elements, 128x2 bits representing ~2MB worth of media
734 * storage. Bit patterns are as follows:
741 struct hammer2_bmap_data {
742 int32_t linear; /* 00 linear sub-granular allocation offset */
743 uint16_t class; /* 04-05 clustering class ((type<<8)|radix) */
744 uint8_t reserved06; /* 06 */
745 uint8_t reserved07; /* 07 */
746 uint32_t reserved08; /* 08 */
747 uint32_t reserved0C; /* 0C */
748 uint32_t reserved10; /* 10 */
749 uint32_t reserved14; /* 14 */
750 uint32_t reserved18; /* 18 */
751 uint32_t avail; /* 1C */
752 uint32_t bitmap[8]; /* 20-3F 256 bits manages 2MB/16KB/2-bits */
755 typedef struct hammer2_bmap_data hammer2_bmap_data_t;
758 * In HAMMER2 inodes ARE directory entries, with a special exception for
759 * hardlinks. The inode number is stored in the inode rather than being
760 * based on the location of the inode (since the location moves every time
761 * the inode or anything underneath the inode is modified).
763 * The inode is 1024 bytes, made up of 256 bytes of meta-data, 256 bytes
764 * for the filename, and 512 bytes worth of direct file data OR an embedded
767 * Directories represent one inode per blockref. Inodes are not laid out
768 * as a file but instead are represented by the related blockrefs. The
769 * blockrefs, in turn, are indexed by the 64-bit directory hash key. Remember
770 * that blocksets are fully associative, so a certain degree efficiency is
771 * achieved just from that.
773 * Up to 512 bytes of direct data can be embedded in an inode, and since
774 * inodes are essentially directory entries this also means that small data
775 * files end up simply being laid out linearly in the directory, resulting
776 * in fewer seeks and highly optimal access.
778 * The compression mode can be changed at any time in the inode and is
779 * recorded on a blockref-by-blockref basis.
781 * Hardlinks are supported via the inode map. Essentially the way a hardlink
782 * works is that all individual directory entries representing the same file
783 * are special cased and specify the same inode number. The actual file
784 * is placed in the nearest parent directory that is parent to all instances
785 * of the hardlink. If all hardlinks to a file are in the same directory
786 * the actual file will also be placed in that directory. This file uses
787 * the inode number as the directory entry key and is invisible to normal
788 * directory scans. Real directory entry keys are differentiated from the
789 * inode number key via bit 63. Access to the hardlink silently looks up
790 * the real file and forwards all operations to that file. Removal of the
791 * last hardlink also removes the real file.
793 * (attr_tid) is only updated when the inode's specific attributes or regular
794 * file size has changed, and affects path lookups and stat. (attr_tid)
795 * represents a special cache coherency lock under the inode. The inode
796 * blockref's modify_tid will always cover it.
798 * (dirent_tid) is only updated when an entry under a directory inode has
799 * been created, deleted, renamed, or had its attributes change, and affects
800 * directory lookups and scans. (dirent_tid) represents another special cache
801 * coherency lock under the inode. The inode blockref's modify_tid will
804 #define HAMMER2_INODE_BYTES 1024 /* (asserted by code) */
805 #define HAMMER2_INODE_MAXNAME 256 /* maximum name in bytes */
806 #define HAMMER2_INODE_VERSION_ONE 1
808 #define HAMMER2_INODE_HIDDENDIR 16 /* special inode */
809 #define HAMMER2_INODE_START 1024 /* dynamically allocated */
811 struct hammer2_inode_data {
812 uint16_t version; /* 0000 inode data version */
813 uint8_t reserved02; /* 0002 */
814 uint8_t pfs_subtype; /* 0003 pfs sub-type */
817 * core inode attributes, inode type, misc flags
819 uint32_t uflags; /* 0004 chflags */
820 uint32_t rmajor; /* 0008 available for device nodes */
821 uint32_t rminor; /* 000C available for device nodes */
822 uint64_t ctime; /* 0010 inode change time */
823 uint64_t mtime; /* 0018 modified time */
824 uint64_t atime; /* 0020 access time (unsupported) */
825 uint64_t btime; /* 0028 birth time */
826 uuid_t uid; /* 0030 uid / degenerate unix uid */
827 uuid_t gid; /* 0040 gid / degenerate unix gid */
829 uint8_t type; /* 0050 object type */
830 uint8_t op_flags; /* 0051 operational flags */
831 uint16_t cap_flags; /* 0052 capability flags */
832 uint32_t mode; /* 0054 unix modes (typ low 16 bits) */
835 * inode size, identification, localized recursive configuration
836 * for compression and backup copies.
838 hammer2_tid_t inum; /* 0058 inode number */
839 hammer2_off_t size; /* 0060 size of file */
840 uint64_t nlinks; /* 0068 hard links (typ only dirs) */
841 hammer2_tid_t iparent; /* 0070 parent inum (recovery only) */
842 hammer2_key_t name_key; /* 0078 full filename key */
843 uint16_t name_len; /* 0080 filename length */
844 uint8_t ncopies; /* 0082 ncopies to local media */
845 uint8_t comp_algo; /* 0083 compression request & algo */
848 * These fields are currently only applicable to PFSROOTs.
850 * NOTE: We can't use {volume_data->fsid, pfs_clid} to uniquely
851 * identify an instance of a PFS in the cluster because
852 * a mount may contain more than one copy of the PFS as
853 * a separate node. {pfs_clid, pfs_fsid} must be used for
854 * registration in the cluster.
856 uint8_t target_type; /* 0084 hardlink target type */
857 uint8_t check_algo; /* 0085 check code request & algo */
858 uint8_t pfs_nmasters; /* 0086 (if PFSROOT) if multi-master */
859 uint8_t pfs_type; /* 0087 (if PFSROOT) node type */
860 uint64_t pfs_inum; /* 0088 (if PFSROOT) inum allocator */
861 uuid_t pfs_clid; /* 0090 (if PFSROOT) cluster uuid */
862 uuid_t pfs_fsid; /* 00A0 (if PFSROOT) unique uuid */
865 * Quotas and aggregate sub-tree inode and data counters. Note that
866 * quotas are not replicated downward, they are explicitly set by
867 * the sysop and in-memory structures keep track of inheritence.
869 hammer2_key_t data_quota; /* 00B0 subtree quota in bytes */
870 hammer2_key_t data_count; /* 00B8 subtree byte count */
871 hammer2_key_t inode_quota; /* 00C0 subtree quota inode count */
872 hammer2_key_t inode_count; /* 00C8 subtree inode count */
873 hammer2_tid_t attr_tid; /* 00D0 attributes changed */
874 hammer2_tid_t dirent_tid; /* 00D8 directory/attr changed */
877 * Tracks (possibly degenerate) free areas covering all sub-tree
878 * allocations under inode, not counting the inode itself.
879 * 0/0 indicates empty entry. fully set-associative.
881 * (not yet implemented)
883 uint64_t decrypt_check; /* 00E0 decryption validator */
884 hammer2_off_t reservedE0[3]; /* 00E8/F0/F8 */
886 unsigned char filename[HAMMER2_INODE_MAXNAME];
887 /* 0100-01FF (256 char, unterminated) */
888 union { /* 0200-03FF (64x8 = 512 bytes) */
889 struct hammer2_blockset blockset;
890 char data[HAMMER2_EMBEDDED_BYTES];
894 typedef struct hammer2_inode_data hammer2_inode_data_t;
896 #define HAMMER2_OPFLAG_DIRECTDATA 0x01
897 #define HAMMER2_OPFLAG_PFSROOT 0x02 /* (see also bref flag) */
898 #define HAMMER2_OPFLAG_COPYIDS 0x04 /* copyids override parent */
900 #define HAMMER2_OBJTYPE_UNKNOWN 0
901 #define HAMMER2_OBJTYPE_DIRECTORY 1
902 #define HAMMER2_OBJTYPE_REGFILE 2
903 #define HAMMER2_OBJTYPE_FIFO 4
904 #define HAMMER2_OBJTYPE_CDEV 5
905 #define HAMMER2_OBJTYPE_BDEV 6
906 #define HAMMER2_OBJTYPE_SOFTLINK 7
907 #define HAMMER2_OBJTYPE_HARDLINK 8 /* dummy entry for hardlink */
908 #define HAMMER2_OBJTYPE_SOCKET 9
909 #define HAMMER2_OBJTYPE_WHITEOUT 10
911 #define HAMMER2_COPYID_NONE 0
912 #define HAMMER2_COPYID_LOCAL ((uint8_t)-1)
914 #define HAMMER2_COPYID_COUNT 256
917 * PFS types identify the role of a PFS within a cluster. The PFS types
918 * is stored on media and in LNK_SPAN messages and used in other places.
920 * The low 4 bits specify the current active type while the high 4 bits
921 * specify the transition target if the PFS is being upgraded or downgraded,
922 * If the upper 4 bits are not zero it may effect how a PFS is used during
925 * Generally speaking, downgrading a MASTER to a SLAVE cannot complete until
926 * at least all MASTERs have updated their pfs_nmasters field. And upgrading
927 * a SLAVE to a MASTER cannot complete until the new prospective master has
928 * been fully synchronized (though theoretically full synchronization is
929 * not required if a (new) quorum of other masters are fully synchronized).
931 * It generally does not matter which PFS element you actually mount, you
932 * are mounting 'the cluster'. So, for example, a network mount will mount
933 * a DUMMY PFS type on a memory filesystem. However, there are two exceptions.
934 * In order to gain the benefits of a SOFT_MASTER or SOFT_SLAVE, those PFSs
935 * must be directly mounted.
937 #define HAMMER2_PFSTYPE_NONE 0x00
938 #define HAMMER2_PFSTYPE_CACHE 0x01
939 #define HAMMER2_PFSTYPE_UNUSED02 0x02
940 #define HAMMER2_PFSTYPE_SLAVE 0x03
941 #define HAMMER2_PFSTYPE_SOFT_SLAVE 0x04
942 #define HAMMER2_PFSTYPE_SOFT_MASTER 0x05
943 #define HAMMER2_PFSTYPE_MASTER 0x06
944 #define HAMMER2_PFSTYPE_UNUSED07 0x07
945 #define HAMMER2_PFSTYPE_SUPROOT 0x08
946 #define HAMMER2_PFSTYPE_DUMMY 0x09
947 #define HAMMER2_PFSTYPE_MAX 16
949 #define HAMMER2_PFSTRAN_NONE 0x00 /* no transition in progress */
950 #define HAMMER2_PFSTRAN_CACHE 0x10
951 #define HAMMER2_PFSTRAN_UNMUSED20 0x20
952 #define HAMMER2_PFSTRAN_SLAVE 0x30
953 #define HAMMER2_PFSTRAN_SOFT_SLAVE 0x40
954 #define HAMMER2_PFSTRAN_SOFT_MASTER 0x50
955 #define HAMMER2_PFSTRAN_MASTER 0x60
956 #define HAMMER2_PFSTRAN_UNUSED70 0x70
957 #define HAMMER2_PFSTRAN_SUPROOT 0x80
958 #define HAMMER2_PFSTRAN_DUMMY 0x90
960 #define HAMMER2_PFS_DEC(n) ((n) & 0x0F)
961 #define HAMMER2_PFS_DEC_TRANSITION(n) (((n) >> 4) & 0x0F)
962 #define HAMMER2_PFS_ENC_TRANSITION(n) (((n) & 0x0F) << 4)
964 #define HAMMER2_PFSSUBTYPE_NONE 0
965 #define HAMMER2_PFSSUBTYPE_SNAPSHOT 1 /* manual/managed snapshot */
966 #define HAMMER2_PFSSUBTYPE_AUTOSNAP 2 /* automatic snapshot */
969 * PFS mode of operation is a bitmask. This is typically not stored
970 * on-media, but defined here because the field may be used in dmsgs.
972 #define HAMMER2_PFSMODE_QUORUM 0x01
973 #define HAMMER2_PFSMODE_RW 0x02
982 * Flags (8 bits) - blockref, for freemap only
984 * Note that the minimum chunk size is 1KB so we could theoretically have
985 * 10 bits here, but we might have some future extension that allows a
986 * chunk size down to 256 bytes and if so we will need bits 8 and 9.
988 #define HAMMER2_AVF_SELMASK 0x03 /* select group */
989 #define HAMMER2_AVF_ALL_ALLOC 0x04 /* indicate all allocated */
990 #define HAMMER2_AVF_ALL_FREE 0x08 /* indicate all free */
991 #define HAMMER2_AVF_RESERVED10 0x10
992 #define HAMMER2_AVF_RESERVED20 0x20
993 #define HAMMER2_AVF_RESERVED40 0x40
994 #define HAMMER2_AVF_RESERVED80 0x80
995 #define HAMMER2_AVF_AVMASK32 ((uint32_t)0xFFFFFF00LU)
996 #define HAMMER2_AVF_AVMASK64 ((uint64_t)0xFFFFFFFFFFFFFF00LLU)
998 #define HAMMER2_AV_SELECT_A 0x00
999 #define HAMMER2_AV_SELECT_B 0x01
1000 #define HAMMER2_AV_SELECT_C 0x02
1001 #define HAMMER2_AV_SELECT_D 0x03
1004 * The volume header eats a 64K block. There is currently an issue where
1005 * we want to try to fit all nominal filesystem updates in a 512-byte section
1006 * but it may be a lost cause due to the need for a blockset.
1008 * All information is stored in host byte order. The volume header's magic
1009 * number may be checked to determine the byte order. If you wish to mount
1010 * between machines w/ different endian modes you'll need filesystem code
1011 * which acts on the media data consistently (either all one way or all the
1012 * other). Our code currently does not do that.
1014 * A read-write mount may have to recover missing allocations by doing an
1015 * incremental mirror scan looking for modifications made after alloc_tid.
1016 * If alloc_tid == last_tid then no recovery operation is needed. Recovery
1017 * operations are usually very, very fast.
1019 * Read-only mounts do not need to do any recovery, access to the filesystem
1020 * topology is always consistent after a crash (is always consistent, period).
1021 * However, there may be shortcutted blockref updates present from deep in
1022 * the tree which are stored in the volumeh eader and must be tracked on
1025 * NOTE: The copyinfo[] array contains the configuration for both the
1026 * cluster connections and any local media copies. The volume
1027 * header will be replicated for each local media copy.
1029 * The mount command may specify multiple medias or just one and
1030 * allow HAMMER2 to pick up the others when it checks the copyinfo[]
1033 * NOTE: root_blockref points to the super-root directory, not the root
1034 * directory. The root directory will be a subdirectory under the
1037 * The super-root directory contains all root directories and all
1038 * snapshots (readonly or writable). It is possible to do a
1039 * null-mount of the super-root using special path constructions
1040 * relative to your mounted root.
1042 * NOTE: HAMMER2 allows any subdirectory tree to be managed as if it were
1043 * a PFS, including mirroring and storage quota operations, and this is
1044 * prefered over creating discrete PFSs in the super-root. Instead
1045 * the super-root is most typically used to create writable snapshots,
1046 * alternative roots, and so forth. The super-root is also used by
1047 * the automatic snapshotting mechanism.
1049 #define HAMMER2_VOLUME_ID_HBO 0x48414d3205172011LLU
1050 #define HAMMER2_VOLUME_ID_ABO 0x11201705324d4148LLU
1052 struct hammer2_volume_data {
1054 * sector #0 - 512 bytes
1056 uint64_t magic; /* 0000 Signature */
1057 hammer2_off_t boot_beg; /* 0008 Boot area (future) */
1058 hammer2_off_t boot_end; /* 0010 (size = end - beg) */
1059 hammer2_off_t aux_beg; /* 0018 Aux area (future) */
1060 hammer2_off_t aux_end; /* 0020 (size = end - beg) */
1061 hammer2_off_t volu_size; /* 0028 Volume size, bytes */
1063 uint32_t version; /* 0030 */
1064 uint32_t flags; /* 0034 */
1065 uint8_t copyid; /* 0038 copyid of phys vol */
1066 uint8_t freemap_version; /* 0039 freemap algorithm */
1067 uint8_t peer_type; /* 003A HAMMER2_PEER_xxx */
1068 uint8_t reserved003B; /* 003B */
1069 uint32_t reserved003C; /* 003C */
1071 uuid_t fsid; /* 0040 */
1072 uuid_t fstype; /* 0050 */
1075 * allocator_size is precalculated at newfs time and does not include
1076 * reserved blocks, boot, or redo areas.
1078 * Initial non-reserved-area allocations do not use the freemap
1079 * but instead adjust alloc_iterator. Dynamic allocations take
1080 * over starting at (allocator_beg). This makes newfs_hammer2's
1081 * job a lot easier and can also serve as a testing jig.
1083 hammer2_off_t allocator_size; /* 0060 Total data space */
1084 hammer2_off_t allocator_free; /* 0068 Free space */
1085 hammer2_off_t allocator_beg; /* 0070 Initial allocations */
1088 * mirror_tid reflects the highest committed super-root change
1089 * freemap_tid reflects the highest committed freemap change
1091 * NOTE: mirror_tid does not track (and should not track) changes
1092 * made to or under PFS roots.
1094 hammer2_tid_t mirror_tid; /* 0078 committed tid (vol) */
1095 hammer2_tid_t reserved0080; /* 0080 */
1096 hammer2_tid_t reserved0088; /* 0088 */
1097 hammer2_tid_t freemap_tid; /* 0090 committed tid (fmap) */
1098 hammer2_tid_t bulkfree_tid; /* 0098 bulkfree incremental */
1099 hammer2_tid_t reserved00A0[5]; /* 00A0-00C7 */
1102 * Copyids are allocated dynamically from the copyexists bitmap.
1103 * An id from the active copies set (up to 8, see copyinfo later on)
1104 * may still exist after the copy set has been removed from the
1105 * volume header and its bit will remain active in the bitmap and
1106 * cannot be reused until it is 100% removed from the hierarchy.
1108 uint32_t copyexists[8]; /* 00C8-00E7 copy exists bmap */
1109 char reserved0140[248]; /* 00E8-01DF */
1112 * 32 bit CRC array at the end of the first 512 byte sector.
1114 * icrc_sects[7] - First 512-4 bytes of volume header (including all
1115 * the other icrc's except this one).
1117 * icrc_sects[6] - Sector 1 (512 bytes) of volume header, which is
1118 * the blockset for the root.
1120 * icrc_sects[5] - Sector 2
1121 * icrc_sects[4] - Sector 3
1122 * icrc_sects[3] - Sector 4 (the freemap blockset)
1124 hammer2_crc32_t icrc_sects[8]; /* 01E0-01FF */
1127 * sector #1 - 512 bytes
1129 * The entire sector is used by a blockset.
1131 hammer2_blockset_t sroot_blockset; /* 0200-03FF Superroot dir */
1136 char sector2[512]; /* 0400-05FF reserved */
1137 char sector3[512]; /* 0600-07FF reserved */
1138 hammer2_blockset_t freemap_blockset; /* 0800-09FF freemap */
1139 char sector5[512]; /* 0A00-0BFF reserved */
1140 char sector6[512]; /* 0C00-0DFF reserved */
1141 char sector7[512]; /* 0E00-0FFF reserved */
1144 * sector #8-71 - 32768 bytes
1146 * Contains the configuration for up to 256 copyinfo targets. These
1147 * specify local and remote copies operating as masters or slaves.
1148 * copyid's 0 and 255 are reserved (0 indicates an empty slot and 255
1149 * indicates the local media).
1151 * Each inode contains a set of up to 8 copyids, either inherited
1152 * from its parent or explicitly specified in the inode, which
1153 * indexes into this array.
1155 /* 1000-8FFF copyinfo config */
1156 hammer2_volconf_t copyinfo[HAMMER2_COPYID_COUNT];
1159 * Remaining sections are reserved for future use.
1161 char reserved0400[0x6FFC]; /* 9000-FFFB reserved */
1164 * icrc on entire volume header
1166 hammer2_crc32_t icrc_volheader; /* FFFC-FFFF full volume icrc*/
1169 typedef struct hammer2_volume_data hammer2_volume_data_t;
1172 * Various parts of the volume header have their own iCRCs.
1174 * The first 512 bytes has its own iCRC stored at the end of the 512 bytes
1175 * and not included the icrc calculation.
1177 * The second 512 bytes also has its own iCRC but it is stored in the first
1178 * 512 bytes so it covers the entire second 512 bytes.
1180 * The whole volume block (64KB) has an iCRC covering all but the last 4 bytes,
1181 * which is where the iCRC for the whole volume is stored. This is currently
1182 * a catch-all for anything not individually iCRCd.
1184 #define HAMMER2_VOL_ICRC_SECT0 7
1185 #define HAMMER2_VOL_ICRC_SECT1 6
1187 #define HAMMER2_VOLUME_BYTES 65536
1189 #define HAMMER2_VOLUME_ICRC0_OFF 0
1190 #define HAMMER2_VOLUME_ICRC1_OFF 512
1191 #define HAMMER2_VOLUME_ICRCVH_OFF 0
1193 #define HAMMER2_VOLUME_ICRC0_SIZE (512 - 4)
1194 #define HAMMER2_VOLUME_ICRC1_SIZE (512)
1195 #define HAMMER2_VOLUME_ICRCVH_SIZE (65536 - 4)
1197 #define HAMMER2_VOL_VERSION_MIN 1
1198 #define HAMMER2_VOL_VERSION_DEFAULT 1
1199 #define HAMMER2_VOL_VERSION_WIP 2
1201 #define HAMMER2_NUM_VOLHDRS 4
1203 union hammer2_media_data {
1204 hammer2_volume_data_t voldata;
1205 hammer2_inode_data_t ipdata;
1206 hammer2_blockref_t npdata[HAMMER2_IND_COUNT_MAX];
1207 hammer2_bmap_data_t bmdata[HAMMER2_FREEMAP_COUNT];
1208 char buf[HAMMER2_PBUFSIZE];
1211 typedef union hammer2_media_data hammer2_media_data_t;
1213 #endif /* !_VFS_HAMMER2_DISK_H_ */