2 * Copyright (c) 2011-2018 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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25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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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 512 x 128-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 ~6 indirect block levels
78 * using 64KB indirect blocks (128 byte refs, 512 or radix 9 per indblk).
80 * 16(datablk) + 9 + 9 + 9 + 9 + 9 + 9 = ~70.
81 * 16(datablk) + 7 + 9 + 9 + 9 + 9 + 9 = ~68. (smaller top level indblk)
83 * The actual depth depends on copies redundancy and whether the filesystem
84 * has chosen to use a smaller indirect block size at the top level or not.
86 #define HAMMER2_ALLOC_MIN 1024 /* minimum allocation size */
87 #define HAMMER2_RADIX_MIN 10 /* minimum allocation size 2^N */
88 #define HAMMER2_ALLOC_MAX 65536 /* maximum allocation size */
89 #define HAMMER2_RADIX_MAX 16 /* maximum allocation size 2^N */
90 #define HAMMER2_RADIX_KEY 64 /* number of bits in key */
93 * MINALLOCSIZE - The minimum allocation size. This can be smaller
94 * or larger than the minimum physical IO size.
96 * NOTE: Should not be larger than 1K since inodes
99 * MINIOSIZE - The minimum IO size. This must be less than
100 * or equal to HAMMER2_LBUFSIZE.
102 * HAMMER2_LBUFSIZE - Nominal buffer size for I/O rollups.
104 * HAMMER2_PBUFSIZE - Topological block size used by files for all
105 * blocks except the block straddling EOF.
107 * HAMMER2_SEGSIZE - Allocation map segment size, typically 4MB
108 * (space represented by a level0 bitmap).
111 #define HAMMER2_SEGSIZE (1 << HAMMER2_FREEMAP_LEVEL0_RADIX)
112 #define HAMMER2_SEGRADIX HAMMER2_FREEMAP_LEVEL0_RADIX
114 #define HAMMER2_PBUFRADIX 16 /* physical buf (1<<16) bytes */
115 #define HAMMER2_PBUFSIZE 65536
116 #define HAMMER2_LBUFRADIX 14 /* logical buf (1<<14) bytes */
117 #define HAMMER2_LBUFSIZE 16384
120 * Generally speaking we want to use 16K and 64K I/Os
122 #define HAMMER2_MINIORADIX HAMMER2_LBUFRADIX
123 #define HAMMER2_MINIOSIZE HAMMER2_LBUFSIZE
125 #define HAMMER2_IND_BYTES_MIN 4096
126 #define HAMMER2_IND_BYTES_NOM HAMMER2_LBUFSIZE
127 #define HAMMER2_IND_BYTES_MAX HAMMER2_PBUFSIZE
128 #define HAMMER2_IND_RADIX_MIN 12
129 #define HAMMER2_IND_RADIX_NOM HAMMER2_LBUFRADIX
130 #define HAMMER2_IND_RADIX_MAX HAMMER2_PBUFRADIX
131 #define HAMMER2_IND_COUNT_MIN (HAMMER2_IND_BYTES_MIN / \
132 sizeof(hammer2_blockref_t))
133 #define HAMMER2_IND_COUNT_MAX (HAMMER2_IND_BYTES_MAX / \
134 sizeof(hammer2_blockref_t))
137 * In HAMMER2, arrays of blockrefs are fully set-associative, meaning that
138 * any element can occur at any index and holes can be anywhere. As a
139 * future optimization we will be able to flag that such arrays are sorted
140 * and thus optimize lookups, but for now we don't.
142 * Inodes embed either 512 bytes of direct data or an array of 4 blockrefs,
143 * resulting in highly efficient storage for files <= 512 bytes and for files
144 * <= 512KB. Up to 4 directory entries can be referenced from a directory
145 * without requiring an indirect block.
147 * Indirect blocks are typically either 4KB (64 blockrefs / ~4MB represented),
148 * or 64KB (1024 blockrefs / ~64MB represented).
150 #define HAMMER2_SET_RADIX 2 /* radix 2 = 4 entries */
151 #define HAMMER2_SET_COUNT (1 << HAMMER2_SET_RADIX)
152 #define HAMMER2_EMBEDDED_BYTES 512 /* inode blockset/dd size */
153 #define HAMMER2_EMBEDDED_RADIX 9
155 #define HAMMER2_PBUFMASK (HAMMER2_PBUFSIZE - 1)
156 #define HAMMER2_LBUFMASK (HAMMER2_LBUFSIZE - 1)
157 #define HAMMER2_SEGMASK (HAMMER2_SEGSIZE - 1)
159 #define HAMMER2_LBUFMASK64 ((hammer2_off_t)HAMMER2_LBUFMASK)
160 #define HAMMER2_PBUFSIZE64 ((hammer2_off_t)HAMMER2_PBUFSIZE)
161 #define HAMMER2_PBUFMASK64 ((hammer2_off_t)HAMMER2_PBUFMASK)
162 #define HAMMER2_SEGSIZE64 ((hammer2_off_t)HAMMER2_SEGSIZE)
163 #define HAMMER2_SEGMASK64 ((hammer2_off_t)HAMMER2_SEGMASK)
165 #define HAMMER2_UUID_STRING "5cbb9ad1-862d-11dc-a94d-01301bb8a9f5"
168 * A 4MB segment is reserved at the beginning of each 2GB zone. This segment
169 * contains the volume header (or backup volume header), the free block
170 * table, and possibly other information in the future. A 4MB segment for
171 * freemap is reserved at the beginning of every 1GB.
173 * 4MB = 64 x 64K blocks. Each 4MB segment is broken down as follows:
176 * 0 volume header (for the first four 2GB zones)
177 * 1 freemap00 level1 FREEMAP_LEAF (256 x 128B bitmap data per 1GB)
178 * 2 level2 FREEMAP_NODE (256 x 128B indirect block per 256GB)
179 * 3 level3 FREEMAP_NODE (256 x 128B indirect block per 64TB)
180 * 4 level4 FREEMAP_NODE (256 x 128B indirect block per 16PB)
181 * 5 level5 FREEMAP_NODE (256 x 128B indirect block per 4EB)
182 * 6 freemap01 level1 (rotation)
187 * 11 freemap02 level1 (rotation)
192 * 16 freemap03 level1 (rotation)
197 * 21 freemap04 level1 (rotation)
202 * 26 freemap05 level1 (rotation)
207 * 31 freemap06 level1 (rotation)
212 * 36 freemap07 level1 (rotation)
222 * The first four 2GB zones contain volume headers and volume header backups.
223 * After that the volume header block# is reserved for future use. Similarly,
224 * there are many blocks related to various Freemap levels which are not
225 * used in every segment and those are also reserved for future use.
226 * Note that each FREEMAP_LEAF or FREEMAP_NODE uses 32KB out of 64KB slot.
228 * Freemap (see the FREEMAP document)
230 * The freemap utilizes blocks #1-40 in 8 sets of 5 blocks. Each block in
231 * a set represents a level of depth in the freemap topology. Eight sets
232 * exist to prevent live updates from disturbing the state of the freemap
233 * were a crash/reboot to occur. That is, a live update is not committed
234 * until the update's flush reaches the volume root. There are FOUR volume
235 * roots representing the last four synchronization points, so the freemap
236 * must be consistent no matter which volume root is chosen by the mount
239 * Each freemap set is 5 x 64K blocks and represents the 1GB, 256GB, 64TB,
240 * 16PB and 4EB indirect map. The volume header itself has a set of 4 freemap
241 * blockrefs representing another 2 bits, giving us a total 64 bits of
242 * representable address space.
244 * The Level 0 64KB block represents 1GB of storage represented by 32KB
245 * (256 x struct hammer2_bmap_data). Each structure represents 4MB of storage
246 * and has a 512 bit bitmap, using 2 bits to represent a 16KB chunk of
247 * storage. These 2 bits represent the following states:
250 * 01 (reserved) (Possibly partially allocated)
254 * One important thing to note here is that the freemap resolution is 16KB,
255 * but the minimum storage allocation size is 1KB. The hammer2 vfs keeps
256 * track of sub-allocations in memory, which means that on a unmount or reboot
257 * the entire 16KB of a partially allocated block will be considered fully
258 * allocated. It is possible for fragmentation to build up over time, but
259 * defragmentation is fairly easy to accomplish since all modifications
260 * allocate a new block.
262 * The Second thing to note is that due to the way snapshots and inode
263 * replication works, deleting a file cannot immediately free the related
264 * space. Furthermore, deletions often do not bother to traverse the
265 * block subhierarchy being deleted. And to go even further, whole
266 * sub-directory trees can be deleted simply by deleting the directory inode
267 * at the top. So even though we have a symbol to represent a 'possibly free'
268 * block (binary 10), only the bulk free scanning code can actually use it.
269 * Normal 'rm's or other deletions do not.
271 * WARNING! ZONE_SEG and VOLUME_ALIGN must be a multiple of 1<<LEVEL0_RADIX
272 * (i.e. a multiple of 4MB). VOLUME_ALIGN must be >= ZONE_SEG.
276 * (1) Modifications to freemap blocks 'allocate' a new copy (aka use a block
277 * from the next set). The new copy is reused until a flush occurs at
278 * which point the next modification will then rotate to the next set.
280 #define HAMMER2_VOLUME_ALIGN (8 * 1024 * 1024)
281 #define HAMMER2_VOLUME_ALIGN64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGN)
282 #define HAMMER2_VOLUME_ALIGNMASK (HAMMER2_VOLUME_ALIGN - 1)
283 #define HAMMER2_VOLUME_ALIGNMASK64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGNMASK)
285 #define HAMMER2_NEWFS_ALIGN (HAMMER2_VOLUME_ALIGN)
286 #define HAMMER2_NEWFS_ALIGN64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGN)
287 #define HAMMER2_NEWFS_ALIGNMASK (HAMMER2_VOLUME_ALIGN - 1)
288 #define HAMMER2_NEWFS_ALIGNMASK64 ((hammer2_off_t)HAMMER2_NEWFS_ALIGNMASK)
290 #define HAMMER2_ZONE_BYTES64 (2LLU * 1024 * 1024 * 1024)
291 #define HAMMER2_ZONE_MASK64 (HAMMER2_ZONE_BYTES64 - 1)
292 #define HAMMER2_ZONE_SEG (4 * 1024 * 1024)
293 #define HAMMER2_ZONE_SEG64 ((hammer2_off_t)HAMMER2_ZONE_SEG)
294 #define HAMMER2_ZONE_BLOCKS_SEG (HAMMER2_ZONE_SEG / HAMMER2_PBUFSIZE)
296 #define HAMMER2_ZONE_FREEMAP_INC 5 /* 5 deep */
298 #define HAMMER2_ZONE_VOLHDR 0 /* volume header or backup */
299 #define HAMMER2_ZONE_FREEMAP_00 1 /* normal freemap rotation */
300 #define HAMMER2_ZONE_FREEMAP_01 6 /* normal freemap rotation */
301 #define HAMMER2_ZONE_FREEMAP_02 11 /* normal freemap rotation */
302 #define HAMMER2_ZONE_FREEMAP_03 16 /* normal freemap rotation */
303 #define HAMMER2_ZONE_FREEMAP_04 21 /* normal freemap rotation */
304 #define HAMMER2_ZONE_FREEMAP_05 26 /* normal freemap rotation */
305 #define HAMMER2_ZONE_FREEMAP_06 31 /* normal freemap rotation */
306 #define HAMMER2_ZONE_FREEMAP_07 36 /* normal freemap rotation */
307 #define HAMMER2_ZONE_FREEMAP_END 41 /* (non-inclusive) */
309 #define HAMMER2_ZONE_UNUSED41 41
310 #define HAMMER2_ZONE_UNUSED42 42
311 #define HAMMER2_ZONE_UNUSED43 43
312 #define HAMMER2_ZONE_UNUSED44 44
313 #define HAMMER2_ZONE_UNUSED45 45
314 #define HAMMER2_ZONE_UNUSED46 46
315 #define HAMMER2_ZONE_UNUSED47 47
316 #define HAMMER2_ZONE_UNUSED48 48
317 #define HAMMER2_ZONE_UNUSED49 49
318 #define HAMMER2_ZONE_UNUSED50 50
319 #define HAMMER2_ZONE_UNUSED51 51
320 #define HAMMER2_ZONE_UNUSED52 52
321 #define HAMMER2_ZONE_UNUSED53 53
322 #define HAMMER2_ZONE_UNUSED54 54
323 #define HAMMER2_ZONE_UNUSED55 55
324 #define HAMMER2_ZONE_UNUSED56 56
325 #define HAMMER2_ZONE_UNUSED57 57
326 #define HAMMER2_ZONE_UNUSED58 58
327 #define HAMMER2_ZONE_UNUSED59 59
328 #define HAMMER2_ZONE_UNUSED60 60
329 #define HAMMER2_ZONE_UNUSED61 61
330 #define HAMMER2_ZONE_UNUSED62 62
331 #define HAMMER2_ZONE_UNUSED63 63
332 #define HAMMER2_ZONE_END 64 /* non-inclusive */
334 #define HAMMER2_NFREEMAPS 8 /* FREEMAP_00 - FREEMAP_07 */
336 /* relative to FREEMAP_x */
337 #define HAMMER2_ZONEFM_LEVEL1 0 /* 1GB leafmap */
338 #define HAMMER2_ZONEFM_LEVEL2 1 /* 256GB indmap */
339 #define HAMMER2_ZONEFM_LEVEL3 2 /* 64TB indmap */
340 #define HAMMER2_ZONEFM_LEVEL4 3 /* 16PB indmap */
341 #define HAMMER2_ZONEFM_LEVEL5 4 /* 4EB indmap */
342 /* LEVEL6 is a set of 4 blockrefs in the volume header 16EB */
345 * Freemap radix. Assumes a set-count of 4, 128-byte blockrefs,
346 * 32KB indirect block for freemap (LEVELN_PSIZE below).
348 * Leaf entry represents 4MB of storage broken down into a 512-bit
349 * bitmap, 2-bits per entry. So course bitmap item represents 16KB.
351 #if HAMMER2_SET_COUNT != 4
352 #error "hammer2_disk.h - freemap assumes SET_COUNT is 4"
354 #define HAMMER2_FREEMAP_LEVEL6_RADIX 64 /* 16EB (end) */
355 #define HAMMER2_FREEMAP_LEVEL5_RADIX 62 /* 4EB */
356 #define HAMMER2_FREEMAP_LEVEL4_RADIX 54 /* 16PB */
357 #define HAMMER2_FREEMAP_LEVEL3_RADIX 46 /* 64TB */
358 #define HAMMER2_FREEMAP_LEVEL2_RADIX 38 /* 256GB */
359 #define HAMMER2_FREEMAP_LEVEL1_RADIX 30 /* 1GB */
360 #define HAMMER2_FREEMAP_LEVEL0_RADIX 22 /* 4MB (128by in l-1 leaf) */
362 #define HAMMER2_FREEMAP_LEVELN_PSIZE 32768 /* physical bytes */
364 #define HAMMER2_FREEMAP_LEVEL5_SIZE ((hammer2_off_t)1 << \
365 HAMMER2_FREEMAP_LEVEL5_RADIX)
366 #define HAMMER2_FREEMAP_LEVEL4_SIZE ((hammer2_off_t)1 << \
367 HAMMER2_FREEMAP_LEVEL4_RADIX)
368 #define HAMMER2_FREEMAP_LEVEL3_SIZE ((hammer2_off_t)1 << \
369 HAMMER2_FREEMAP_LEVEL3_RADIX)
370 #define HAMMER2_FREEMAP_LEVEL2_SIZE ((hammer2_off_t)1 << \
371 HAMMER2_FREEMAP_LEVEL2_RADIX)
372 #define HAMMER2_FREEMAP_LEVEL1_SIZE ((hammer2_off_t)1 << \
373 HAMMER2_FREEMAP_LEVEL1_RADIX)
374 #define HAMMER2_FREEMAP_LEVEL0_SIZE ((hammer2_off_t)1 << \
375 HAMMER2_FREEMAP_LEVEL0_RADIX)
377 #define HAMMER2_FREEMAP_LEVEL5_MASK (HAMMER2_FREEMAP_LEVEL5_SIZE - 1)
378 #define HAMMER2_FREEMAP_LEVEL4_MASK (HAMMER2_FREEMAP_LEVEL4_SIZE - 1)
379 #define HAMMER2_FREEMAP_LEVEL3_MASK (HAMMER2_FREEMAP_LEVEL3_SIZE - 1)
380 #define HAMMER2_FREEMAP_LEVEL2_MASK (HAMMER2_FREEMAP_LEVEL2_SIZE - 1)
381 #define HAMMER2_FREEMAP_LEVEL1_MASK (HAMMER2_FREEMAP_LEVEL1_SIZE - 1)
382 #define HAMMER2_FREEMAP_LEVEL0_MASK (HAMMER2_FREEMAP_LEVEL0_SIZE - 1)
384 #define HAMMER2_FREEMAP_COUNT (int)(HAMMER2_FREEMAP_LEVELN_PSIZE / \
385 sizeof(hammer2_bmap_data_t))
388 * XXX I made a mistake and made the reserved area begin at each LEVEL1 zone,
389 * which is on a 1GB demark. This will eat a little more space but for
390 * now we retain compatibility and make FMZONEBASE every 1GB
392 #define H2FMZONEBASE(key) ((key) & ~HAMMER2_FREEMAP_LEVEL1_MASK)
393 #define H2FMBASE(key, radix) ((key) & ~(((hammer2_off_t)1 << (radix)) - 1))
396 * 16KB bitmap granularity (x2 bits per entry).
398 #define HAMMER2_FREEMAP_BLOCK_RADIX 14
399 #define HAMMER2_FREEMAP_BLOCK_SIZE (1 << HAMMER2_FREEMAP_BLOCK_RADIX)
400 #define HAMMER2_FREEMAP_BLOCK_MASK (HAMMER2_FREEMAP_BLOCK_SIZE - 1)
403 * bitmap[] structure. 2 bits per HAMMER2_FREEMAP_BLOCK_SIZE.
405 * 8 x 64-bit elements, 2 bits per block.
406 * 32 blocks (radix 5) per element.
407 * representing INDEX_SIZE bytes worth of storage per element.
410 typedef uint64_t hammer2_bitmap_t;
412 #define HAMMER2_BMAP_ALLONES ((hammer2_bitmap_t)-1)
413 #define HAMMER2_BMAP_ELEMENTS 8
414 #define HAMMER2_BMAP_BITS_PER_ELEMENT 64
415 #define HAMMER2_BMAP_INDEX_RADIX 5 /* 32 blocks per element */
416 #define HAMMER2_BMAP_BLOCKS_PER_ELEMENT (1 << HAMMER2_BMAP_INDEX_RADIX)
418 #define HAMMER2_BMAP_INDEX_SIZE (HAMMER2_FREEMAP_BLOCK_SIZE * \
419 HAMMER2_BMAP_BLOCKS_PER_ELEMENT)
420 #define HAMMER2_BMAP_INDEX_MASK (HAMMER2_BMAP_INDEX_SIZE - 1)
422 #define HAMMER2_BMAP_SIZE (HAMMER2_BMAP_INDEX_SIZE * \
423 HAMMER2_BMAP_ELEMENTS)
424 #define HAMMER2_BMAP_MASK (HAMMER2_BMAP_SIZE - 1)
427 * Two linear areas can be reserved after the initial 4MB segment in the base
428 * zone (the one starting at offset 0). These areas are NOT managed by the
429 * block allocator and do not fall under HAMMER2 crc checking rules based
430 * at the volume header (but can be self-CRCd internally, depending).
432 #define HAMMER2_BOOT_MIN_BYTES HAMMER2_VOLUME_ALIGN
433 #define HAMMER2_BOOT_NOM_BYTES (64*1024*1024)
434 #define HAMMER2_BOOT_MAX_BYTES (256*1024*1024)
436 #define HAMMER2_REDO_MIN_BYTES HAMMER2_VOLUME_ALIGN
437 #define HAMMER2_REDO_NOM_BYTES (256*1024*1024)
438 #define HAMMER2_REDO_MAX_BYTES (1024*1024*1024)
441 * Most HAMMER2 types are implemented as unsigned 64-bit integers.
442 * Transaction ids are monotonic.
444 * We utilize 32-bit iSCSI CRCs.
446 typedef uint64_t hammer2_tid_t;
447 typedef uint64_t hammer2_off_t;
448 typedef uint64_t hammer2_key_t;
449 typedef uint32_t hammer2_crc32_t;
452 * Miscellanious ranges (all are unsigned).
454 #define HAMMER2_TID_MIN 1ULL
455 #define HAMMER2_TID_MAX 0xFFFFFFFFFFFFFFFFULL
456 #define HAMMER2_KEY_MIN 0ULL
457 #define HAMMER2_KEY_MAX 0xFFFFFFFFFFFFFFFFULL
458 #define HAMMER2_OFFSET_MIN 0ULL
459 #define HAMMER2_OFFSET_MAX 0xFFFFFFFFFFFFFFFFULL
462 * HAMMER2 data offset special cases and masking.
464 * All HAMMER2 data offsets have to be broken down into a 64K buffer base
465 * offset (HAMMER2_OFF_MASK_HI) and a 64K buffer index (HAMMER2_OFF_MASK_LO).
467 * Indexes into physical buffers are always 64-byte aligned. The low 6 bits
468 * of the data offset field specifies how large the data chunk being pointed
469 * to as a power of 2. The theoretical minimum radix is thus 6 (The space
470 * needed in the low bits of the data offset field). However, the practical
471 * minimum allocation chunk size is 1KB (a radix of 10), so HAMMER2 sets
472 * HAMMER2_RADIX_MIN to 10. The maximum radix is currently 16 (64KB), but
473 * we fully intend to support larger extents in the future.
475 * WARNING! A radix of 0 (such as when data_off is all 0's) is a special
476 * case which means no data associated with the blockref, and
477 * not the '1 byte' it would otherwise calculate to.
479 #define HAMMER2_OFF_BAD ((hammer2_off_t)-1)
480 #define HAMMER2_OFF_MASK 0xFFFFFFFFFFFFFFC0ULL
481 #define HAMMER2_OFF_MASK_LO (HAMMER2_OFF_MASK & HAMMER2_PBUFMASK64)
482 #define HAMMER2_OFF_MASK_HI (~HAMMER2_PBUFMASK64)
483 #define HAMMER2_OFF_MASK_RADIX 0x000000000000003FULL
484 #define HAMMER2_MAX_COPIES 6
487 * HAMMER2 directory support and pre-defined keys
489 #define HAMMER2_DIRHASH_VISIBLE 0x8000000000000000ULL
490 #define HAMMER2_DIRHASH_USERMSK 0x7FFFFFFFFFFFFFFFULL
491 #define HAMMER2_DIRHASH_LOMASK 0x0000000000007FFFULL
492 #define HAMMER2_DIRHASH_HIMASK 0xFFFFFFFFFFFF0000ULL
493 #define HAMMER2_DIRHASH_FORCED 0x0000000000008000ULL /* bit forced on */
495 #define HAMMER2_SROOT_KEY 0x0000000000000000ULL /* volume to sroot */
496 #define HAMMER2_BOOT_KEY 0xd9b36ce135528000ULL /* sroot to BOOT PFS */
498 /************************************************************************
500 ************************************************************************
503 * All HAMMER2 directories directly under the super-root on your local
504 * media can be mounted separately, even if they share the same physical
507 * When you do a HAMMER2 mount you are effectively tying into a HAMMER2
508 * cluster via local media. The local media does not have to participate
509 * in the cluster, other than to provide the hammer2_volconf[] array and
510 * root inode for the mount.
512 * This is important: The mount device path you specify serves to bootstrap
513 * your entry into the cluster, but your mount will make active connections
514 * to ALL copy elements in the hammer2_volconf[] array which match the
515 * PFSID of the directory in the super-root that you specified. The local
516 * media path does not have to be mentioned in this array but becomes part
517 * of the cluster based on its type and access rights. ALL ELEMENTS ARE
518 * TREATED ACCORDING TO TYPE NO MATTER WHICH ONE YOU MOUNT FROM.
520 * The actual cluster may be far larger than the elements you list in the
521 * hammer2_volconf[] array. You list only the elements you wish to
522 * directly connect to and you are able to access the rest of the cluster
523 * indirectly through those connections.
525 * WARNING! This structure must be exactly 128 bytes long for its config
526 * array to fit in the volume header.
528 struct hammer2_volconf {
529 uint8_t copyid; /* 00 copyid 0-255 (must match slot) */
530 uint8_t inprog; /* 01 operation in progress, or 0 */
531 uint8_t chain_to; /* 02 operation chaining to, or 0 */
532 uint8_t chain_from; /* 03 operation chaining from, or 0 */
533 uint16_t flags; /* 04-05 flags field */
534 uint8_t error; /* 06 last operational error */
535 uint8_t priority; /* 07 priority and round-robin flag */
536 uint8_t remote_pfs_type;/* 08 probed direct remote PFS type */
537 uint8_t reserved08[23]; /* 09-1F */
538 uuid_t pfs_clid; /* 20-2F copy target must match this uuid */
539 uint8_t label[16]; /* 30-3F import/export label */
540 uint8_t path[64]; /* 40-7F target specification string or key */
543 typedef struct hammer2_volconf hammer2_volconf_t;
545 #define DMSG_VOLF_ENABLED 0x0001
546 #define DMSG_VOLF_INPROG 0x0002
547 #define DMSG_VOLF_CONN_RR 0x80 /* round-robin at same priority */
548 #define DMSG_VOLF_CONN_EF 0x40 /* media errors flagged */
549 #define DMSG_VOLF_CONN_PRI 0x0F /* select priority 0-15 (15=best) */
551 struct dmsg_lnk_hammer2_volconf {
553 hammer2_volconf_t copy; /* copy spec */
557 int64_t reserved02[32];
560 typedef struct dmsg_lnk_hammer2_volconf dmsg_lnk_hammer2_volconf_t;
562 #define DMSG_LNK_HAMMER2_VOLCONF DMSG_LNK(DMSG_LNK_CMD_HAMMER2_VOLCONF, \
563 dmsg_lnk_hammer2_volconf)
565 #define H2_LNK_VOLCONF(msg) ((dmsg_lnk_hammer2_volconf_t *)(msg)->any.buf)
568 * HAMMER2 directory entry header (embedded in blockref) exactly 16 bytes
570 struct hammer2_dirent_head {
571 hammer2_tid_t inum; /* inode number */
572 uint16_t namlen; /* name length */
573 uint8_t type; /* OBJTYPE_* */
578 typedef struct hammer2_dirent_head hammer2_dirent_head_t;
581 * The media block reference structure. This forms the core of the HAMMER2
582 * media topology recursion. This 128-byte data structure is embedded in the
583 * volume header, in inodes (which are also directory entries), and in
586 * A blockref references a single media item, which typically can be a
587 * directory entry (aka inode), indirect block, or data block.
589 * The primary feature a blockref represents is the ability to validate
590 * the entire tree underneath it via its check code. Any modification to
591 * anything propagates up the blockref tree all the way to the root, replacing
592 * the related blocks and compounding the generated check code.
594 * The check code can be a simple 32-bit iscsi code, a 64-bit crc, or as
595 * complex as a 512 bit cryptographic hash. I originally used a 64-byte
596 * blockref but later expanded it to 128 bytes to be able to support the
597 * larger check code as well as to embed statistics for quota operation.
599 * Simple check codes are not sufficient for unverified dedup. Even with
600 * a maximally-sized check code unverified dedup should only be used in
601 * in subdirectory trees where you do not need 100% data integrity.
603 * Unverified dedup is deduping based on meta-data only without verifying
604 * that the data blocks are actually identical. Verified dedup guarantees
605 * integrity but is a far more I/O-expensive operation.
609 * mirror_tid - per cluster node modified (propagated upward by flush)
610 * modify_tid - clc record modified (not propagated).
611 * update_tid - clc record updated (propagated upward on verification)
613 * CLC - Stands for 'Cluster Level Change', identifiers which are identical
614 * within the topology across all cluster nodes (when fully
617 * NOTE: The range of keys represented by the blockref is (key) to
618 * ((key) + (1LL << keybits) - 1). HAMMER2 usually populates
619 * blocks bottom-up, inserting a new root when radix expansion
622 * leaf_count - Helps manage leaf collapse calculations when indirect
623 * blocks become mostly empty. This value caps out at
624 * HAMMER2_BLOCKREF_LEAF_MAX (65535).
626 * Used by the chain code to determine when to pull leafs up
627 * from nearly empty indirect blocks. For the purposes of this
628 * calculation, BREF_TYPE_INODE is considered a leaf, along
629 * with DIRENT and DATA.
633 * A number of blockref fields are reserved and should generally be set to
634 * 0 for future compatibility.
636 * FUTURE BLOCKREF EXPANSION
638 * CONTENT ADDRESSABLE INDEXING (future) - Using a 256 or 512-bit check code.
640 struct hammer2_blockref { /* MUST BE EXACTLY 64 BYTES */
641 uint8_t type; /* type of underlying item */
642 uint8_t methods; /* check method & compression method */
643 uint8_t copyid; /* specify which copy this is */
644 uint8_t keybits; /* #of keybits masked off 0=leaf */
645 uint8_t vradix; /* virtual data/meta-data size */
646 uint8_t flags; /* blockref flags */
647 uint16_t leaf_count; /* leaf aggregation count */
648 hammer2_key_t key; /* key specification */
649 hammer2_tid_t mirror_tid; /* media flush topology & freemap */
650 hammer2_tid_t modify_tid; /* clc modify (not propagated) */
651 hammer2_off_t data_off; /* low 6 bits is phys size (radix)*/
652 hammer2_tid_t update_tid; /* clc modify (propagated upward) */
657 * Directory entry header (BREF_TYPE_DIRENT)
659 * NOTE: check.buf contains filename if <= 64 bytes. Longer
660 * filenames are stored in a data reference of size
661 * HAMMER2_ALLOC_MIN (at least 256, typically 1024).
663 * NOTE: inode structure may contain a copy of a recently
664 * associated filename, for recovery purposes.
666 * NOTE: Superroot entries are INODEs, not DIRENTs. Code
669 hammer2_dirent_head_t dirent;
672 * Statistics aggregation (BREF_TYPE_INODE, BREF_TYPE_INDIRECT)
675 hammer2_key_t data_count;
676 hammer2_key_t inode_count;
679 union { /* check info */
683 uint32_t reserved[15];
687 uint64_t reserved[7];
702 * Freemap hints are embedded in addition to the icrc32.
704 * bigmask - Radixes available for allocation (0-31).
705 * Heuristical (may be permissive but not
706 * restrictive). Typically only radix values
707 * 10-16 are used (i.e. (1<<10) through (1<<16)).
709 * avail - Total available space remaining, in bytes
713 uint32_t bigmask; /* available radixes */
714 uint64_t avail; /* total available bytes */
720 typedef struct hammer2_blockref hammer2_blockref_t;
722 #define HAMMER2_BLOCKREF_BYTES 128 /* blockref struct in bytes */
723 #define HAMMER2_BLOCKREF_RADIX 7
725 #define HAMMER2_BLOCKREF_LEAF_MAX 65535
728 * On-media and off-media blockref types.
730 * types >= 128 are pseudo values that should never be present on-media.
732 #define HAMMER2_BREF_TYPE_EMPTY 0
733 #define HAMMER2_BREF_TYPE_INODE 1
734 #define HAMMER2_BREF_TYPE_INDIRECT 2
735 #define HAMMER2_BREF_TYPE_DATA 3
736 #define HAMMER2_BREF_TYPE_DIRENT 4
737 #define HAMMER2_BREF_TYPE_FREEMAP_NODE 5
738 #define HAMMER2_BREF_TYPE_FREEMAP_LEAF 6
739 #define HAMMER2_BREF_TYPE_FREEMAP 254 /* pseudo-type */
740 #define HAMMER2_BREF_TYPE_VOLUME 255 /* pseudo-type */
742 #define HAMMER2_BREF_FLAG_PFSROOT 0x01 /* see also related opflag */
743 #define HAMMER2_BREF_FLAG_ZERO 0x02
746 * Encode/decode check mode and compression mode for
747 * bref.methods. The compression level is not encoded in
750 #define HAMMER2_ENC_CHECK(n) (((n) & 15) << 4)
751 #define HAMMER2_DEC_CHECK(n) (((n) >> 4) & 15)
752 #define HAMMER2_ENC_COMP(n) ((n) & 15)
753 #define HAMMER2_DEC_COMP(n) ((n) & 15)
755 #define HAMMER2_CHECK_NONE 0
756 #define HAMMER2_CHECK_DISABLED 1
757 #define HAMMER2_CHECK_ISCSI32 2
758 #define HAMMER2_CHECK_XXHASH64 3
759 #define HAMMER2_CHECK_SHA192 4
760 #define HAMMER2_CHECK_FREEMAP 5
762 #define HAMMER2_CHECK_DEFAULT HAMMER2_CHECK_XXHASH64
764 /* user-specifiable check modes only */
765 #define HAMMER2_CHECK_STRINGS { "none", "disabled", "crc32", \
766 "xxhash64", "sha192" }
767 #define HAMMER2_CHECK_STRINGS_COUNT 5
770 * Encode/decode check or compression algorithm request in
771 * ipdata->meta.check_algo and ipdata->meta.comp_algo.
773 #define HAMMER2_ENC_ALGO(n) (n)
774 #define HAMMER2_DEC_ALGO(n) ((n) & 15)
775 #define HAMMER2_ENC_LEVEL(n) ((n) << 4)
776 #define HAMMER2_DEC_LEVEL(n) (((n) >> 4) & 15)
778 #define HAMMER2_COMP_NONE 0
779 #define HAMMER2_COMP_AUTOZERO 1
780 #define HAMMER2_COMP_LZ4 2
781 #define HAMMER2_COMP_ZLIB 3
783 #define HAMMER2_COMP_NEWFS_DEFAULT HAMMER2_COMP_LZ4
784 #define HAMMER2_COMP_STRINGS { "none", "autozero", "lz4", "zlib" }
785 #define HAMMER2_COMP_STRINGS_COUNT 4
788 * Passed to hammer2_chain_create(), causes methods to be inherited from
791 #define HAMMER2_METH_DEFAULT -1
794 * HAMMER2 block references are collected into sets of 4 blockrefs. These
795 * sets are fully associative, meaning the elements making up a set are
796 * not sorted in any way and may contain duplicate entries, holes, or
797 * entries which shortcut multiple levels of indirection. Sets are used
800 * (1) When redundancy is desired a set may contain several duplicate
801 * entries pointing to different copies of the same data. Up to 4 copies
804 * (2) The blockrefs in a set can shortcut multiple levels of indirections
805 * within the bounds imposed by the parent of set.
807 * When a set fills up another level of indirection is inserted, moving
808 * some or all of the set's contents into indirect blocks placed under the
809 * set. This is a top-down approach in that indirect blocks are not created
810 * until the set actually becomes full (that is, the entries in the set can
811 * shortcut the indirect blocks when the set is not full). Depending on how
812 * things are filled multiple indirect blocks will eventually be created.
814 * Indirect blocks are typically 4KB (64 entres) or 64KB (1024 entries) and
815 * are also treated as fully set-associative.
817 struct hammer2_blockset {
818 hammer2_blockref_t blockref[HAMMER2_SET_COUNT];
821 typedef struct hammer2_blockset hammer2_blockset_t;
824 * Catch programmer snafus
826 #if (1 << HAMMER2_SET_RADIX) != HAMMER2_SET_COUNT
827 #error "hammer2 direct radix is incorrect"
829 #if (1 << HAMMER2_PBUFRADIX) != HAMMER2_PBUFSIZE
830 #error "HAMMER2_PBUFRADIX and HAMMER2_PBUFSIZE are inconsistent"
832 #if (1 << HAMMER2_RADIX_MIN) != HAMMER2_ALLOC_MIN
833 #error "HAMMER2_RADIX_MIN and HAMMER2_ALLOC_MIN are inconsistent"
837 * hammer2_bmap_data - A freemap entry in the LEVEL1 block.
839 * Each 128-byte entry contains the bitmap and meta-data required to manage
840 * a LEVEL0 (4MB) block of storage. The storage is managed in 256 x 16KB
843 * A smaller allocation granularity is supported via a linear iterator and/or
844 * must otherwise be tracked in ram.
846 * (data structure must be 128 bytes exactly)
848 * linear - A BYTE linear allocation offset used for sub-16KB allocations
849 * only. May contain values between 0 and 4MB. Must be ignored
850 * if 16KB-aligned (i.e. force bitmap scan), otherwise may be
851 * used to sub-allocate within the 16KB block (which is already
852 * marked as allocated in the bitmap).
854 * Sub-allocations need only be 1KB-aligned and do not have to be
855 * size-aligned, and 16KB or larger allocations do not update this
856 * field, resulting in pretty good packing.
858 * Please note that file data granularity may be limited by
859 * other issues such as buffer cache direct-mapping and the
860 * desire to support sector sizes up to 16KB (so H2 only issues
861 * I/O's in multiples of 16KB anyway).
863 * class - Clustering class. Cleared to 0 only if the entire leaf becomes
864 * free. Used to cluster device buffers so all elements must have
865 * the same device block size, but may mix logical sizes.
867 * Typically integrated with the blockref type in the upper 8 bits
868 * to localize inodes and indrect blocks, improving bulk free scans
869 * and directory scans.
871 * bitmap - Two bits per 16KB allocation block arranged in arrays of
872 * 64-bit elements, 256x2 bits representing ~4MB worth of media
873 * storage. Bit patterns are as follows:
880 struct hammer2_bmap_data {
881 int32_t linear; /* 00 linear sub-granular allocation offset */
882 uint16_t class; /* 04-05 clustering class ((type<<8)|radix) */
883 uint8_t reserved06; /* 06 */
884 uint8_t reserved07; /* 07 */
885 uint32_t reserved08; /* 08 */
886 uint32_t reserved0C; /* 0C */
887 uint32_t reserved10; /* 10 */
888 uint32_t reserved14; /* 14 */
889 uint32_t reserved18; /* 18 */
890 uint32_t avail; /* 1C */
891 uint32_t reserved20[8]; /* 20-3F 256 bits manages 128K/1KB/2-bits */
892 /* 40-7F 512 bits manages 4MB of storage */
893 hammer2_bitmap_t bitmapq[HAMMER2_BMAP_ELEMENTS];
896 typedef struct hammer2_bmap_data hammer2_bmap_data_t;
899 * XXX "Inodes ARE directory entries" is no longer the case. Hardlinks are
900 * dirents which refer to the same inode#, which is how filesystems usually
901 * implement hardlink. The following comments need to be updated.
903 * In HAMMER2 inodes ARE directory entries, with a special exception for
904 * hardlinks. The inode number is stored in the inode rather than being
905 * based on the location of the inode (since the location moves every time
906 * the inode or anything underneath the inode is modified).
908 * The inode is 1024 bytes, made up of 256 bytes of meta-data, 256 bytes
909 * for the filename, and 512 bytes worth of direct file data OR an embedded
910 * blockset. The in-memory hammer2_inode structure contains only the mostly-
911 * node-independent meta-data portion (some flags are node-specific and will
912 * not be synchronized). The rest of the inode is node-specific and chain I/O
913 * is required to obtain it.
915 * Directories represent one inode per blockref. Inodes are not laid out
916 * as a file but instead are represented by the related blockrefs. The
917 * blockrefs, in turn, are indexed by the 64-bit directory hash key. Remember
918 * that blocksets are fully associative, so a certain degree efficiency is
919 * achieved just from that.
921 * Up to 512 bytes of direct data can be embedded in an inode, and since
922 * inodes are essentially directory entries this also means that small data
923 * files end up simply being laid out linearly in the directory, resulting
924 * in fewer seeks and highly optimal access.
926 * The compression mode can be changed at any time in the inode and is
927 * recorded on a blockref-by-blockref basis.
929 * Hardlinks are supported via the inode map. Essentially the way a hardlink
930 * works is that all individual directory entries representing the same file
931 * are special cased and specify the same inode number. The actual file
932 * is placed in the nearest parent directory that is parent to all instances
933 * of the hardlink. If all hardlinks to a file are in the same directory
934 * the actual file will also be placed in that directory. This file uses
935 * the inode number as the directory entry key and is invisible to normal
936 * directory scans. Real directory entry keys are differentiated from the
937 * inode number key via bit 63. Access to the hardlink silently looks up
938 * the real file and forwards all operations to that file. Removal of the
939 * last hardlink also removes the real file.
941 #define HAMMER2_INODE_BYTES 1024 /* (asserted by code) */
942 #define HAMMER2_INODE_MAXNAME 256 /* maximum name in bytes */
943 #define HAMMER2_INODE_VERSION_ONE 1
945 #define HAMMER2_INODE_START 1024 /* dynamically allocated */
947 struct hammer2_inode_meta {
948 uint16_t version; /* 0000 inode data version */
949 uint8_t reserved02; /* 0002 */
950 uint8_t pfs_subtype; /* 0003 pfs sub-type */
953 * core inode attributes, inode type, misc flags
955 uint32_t uflags; /* 0004 chflags */
956 uint32_t rmajor; /* 0008 available for device nodes */
957 uint32_t rminor; /* 000C available for device nodes */
958 uint64_t ctime; /* 0010 inode change time */
959 uint64_t mtime; /* 0018 modified time */
960 uint64_t atime; /* 0020 access time (unsupported) */
961 uint64_t btime; /* 0028 birth time */
962 uuid_t uid; /* 0030 uid / degenerate unix uid */
963 uuid_t gid; /* 0040 gid / degenerate unix gid */
965 uint8_t type; /* 0050 object type */
966 uint8_t op_flags; /* 0051 operational flags */
967 uint16_t cap_flags; /* 0052 capability flags */
968 uint32_t mode; /* 0054 unix modes (typ low 16 bits) */
971 * inode size, identification, localized recursive configuration
972 * for compression and backup copies.
974 * NOTE: Nominal parent inode number (iparent) is only applicable
975 * for directories but can also help for files during
976 * catastrophic recovery.
978 hammer2_tid_t inum; /* 0058 inode number */
979 hammer2_off_t size; /* 0060 size of file */
980 uint64_t nlinks; /* 0068 hard links (typ only dirs) */
981 hammer2_tid_t iparent; /* 0070 nominal parent inum */
982 hammer2_key_t name_key; /* 0078 full filename key */
983 uint16_t name_len; /* 0080 filename length */
984 uint8_t ncopies; /* 0082 ncopies to local media */
985 uint8_t comp_algo; /* 0083 compression request & algo */
988 * These fields are currently only applicable to PFSROOTs.
990 * NOTE: We can't use {volume_data->fsid, pfs_clid} to uniquely
991 * identify an instance of a PFS in the cluster because
992 * a mount may contain more than one copy of the PFS as
993 * a separate node. {pfs_clid, pfs_fsid} must be used for
994 * registration in the cluster.
996 uint8_t target_type; /* 0084 hardlink target type */
997 uint8_t check_algo; /* 0085 check code request & algo */
998 uint8_t pfs_nmasters; /* 0086 (if PFSROOT) if multi-master */
999 uint8_t pfs_type; /* 0087 (if PFSROOT) node type */
1000 uint64_t pfs_inum; /* 0088 (if PFSROOT) inum allocator */
1001 uuid_t pfs_clid; /* 0090 (if PFSROOT) cluster uuid */
1002 uuid_t pfs_fsid; /* 00A0 (if PFSROOT) unique uuid */
1005 * Quotas and aggregate sub-tree inode and data counters. Note that
1006 * quotas are not replicated downward, they are explicitly set by
1007 * the sysop and in-memory structures keep track of inheritance.
1009 hammer2_key_t data_quota; /* 00B0 subtree quota in bytes */
1010 hammer2_key_t unusedB8; /* 00B8 subtree byte count */
1011 hammer2_key_t inode_quota; /* 00C0 subtree quota inode count */
1012 hammer2_key_t unusedC8; /* 00C8 subtree inode count */
1015 * The last snapshot tid is tested against modify_tid to determine
1016 * when a copy must be made of a data block whos check mode has been
1017 * disabled (a disabled check mode allows data blocks to be updated
1018 * in place instead of copy-on-write).
1020 hammer2_tid_t pfs_lsnap_tid; /* 00D0 last snapshot tid */
1021 hammer2_tid_t reservedD8; /* 00D8 (avail) */
1024 * Tracks (possibly degenerate) free areas covering all sub-tree
1025 * allocations under inode, not counting the inode itself.
1026 * 0/0 indicates empty entry. fully set-associative.
1028 * (not yet implemented)
1030 uint64_t decrypt_check; /* 00E0 decryption validator */
1031 hammer2_off_t reservedE0[3]; /* 00E8/F0/F8 */
1034 typedef struct hammer2_inode_meta hammer2_inode_meta_t;
1036 struct hammer2_inode_data {
1037 hammer2_inode_meta_t meta; /* 0000-00FF */
1038 unsigned char filename[HAMMER2_INODE_MAXNAME];
1039 /* 0100-01FF (256 char, unterminated) */
1040 union { /* 0200-03FF (64x8 = 512 bytes) */
1041 hammer2_blockset_t blockset;
1042 char data[HAMMER2_EMBEDDED_BYTES];
1046 typedef struct hammer2_inode_data hammer2_inode_data_t;
1048 #define HAMMER2_OPFLAG_DIRECTDATA 0x01
1049 #define HAMMER2_OPFLAG_PFSROOT 0x02 /* (see also bref flag) */
1050 #define HAMMER2_OPFLAG_COPYIDS 0x04 /* copyids override parent */
1052 #define HAMMER2_OBJTYPE_UNKNOWN 0
1053 #define HAMMER2_OBJTYPE_DIRECTORY 1
1054 #define HAMMER2_OBJTYPE_REGFILE 2
1055 #define HAMMER2_OBJTYPE_FIFO 4
1056 #define HAMMER2_OBJTYPE_CDEV 5
1057 #define HAMMER2_OBJTYPE_BDEV 6
1058 #define HAMMER2_OBJTYPE_SOFTLINK 7
1059 #define HAMMER2_OBJTYPE_UNUSED08 8
1060 #define HAMMER2_OBJTYPE_SOCKET 9
1061 #define HAMMER2_OBJTYPE_WHITEOUT 10
1063 #define HAMMER2_COPYID_NONE 0
1064 #define HAMMER2_COPYID_LOCAL ((uint8_t)-1)
1066 #define HAMMER2_COPYID_COUNT 256
1069 * PFS types identify the role of a PFS within a cluster. The PFS types
1070 * is stored on media and in LNK_SPAN messages and used in other places.
1072 * The low 4 bits specify the current active type while the high 4 bits
1073 * specify the transition target if the PFS is being upgraded or downgraded,
1074 * If the upper 4 bits are not zero it may effect how a PFS is used during
1077 * Generally speaking, downgrading a MASTER to a SLAVE cannot complete until
1078 * at least all MASTERs have updated their pfs_nmasters field. And upgrading
1079 * a SLAVE to a MASTER cannot complete until the new prospective master has
1080 * been fully synchronized (though theoretically full synchronization is
1081 * not required if a (new) quorum of other masters are fully synchronized).
1083 * It generally does not matter which PFS element you actually mount, you
1084 * are mounting 'the cluster'. So, for example, a network mount will mount
1085 * a DUMMY PFS type on a memory filesystem. However, there are two exceptions.
1086 * In order to gain the benefits of a SOFT_MASTER or SOFT_SLAVE, those PFSs
1087 * must be directly mounted.
1089 #define HAMMER2_PFSTYPE_NONE 0x00
1090 #define HAMMER2_PFSTYPE_CACHE 0x01
1091 #define HAMMER2_PFSTYPE_UNUSED02 0x02
1092 #define HAMMER2_PFSTYPE_SLAVE 0x03
1093 #define HAMMER2_PFSTYPE_SOFT_SLAVE 0x04
1094 #define HAMMER2_PFSTYPE_SOFT_MASTER 0x05
1095 #define HAMMER2_PFSTYPE_MASTER 0x06
1096 #define HAMMER2_PFSTYPE_UNUSED07 0x07
1097 #define HAMMER2_PFSTYPE_SUPROOT 0x08
1098 #define HAMMER2_PFSTYPE_DUMMY 0x09
1099 #define HAMMER2_PFSTYPE_MAX 16
1101 #define HAMMER2_PFSTRAN_NONE 0x00 /* no transition in progress */
1102 #define HAMMER2_PFSTRAN_CACHE 0x10
1103 #define HAMMER2_PFSTRAN_UNMUSED20 0x20
1104 #define HAMMER2_PFSTRAN_SLAVE 0x30
1105 #define HAMMER2_PFSTRAN_SOFT_SLAVE 0x40
1106 #define HAMMER2_PFSTRAN_SOFT_MASTER 0x50
1107 #define HAMMER2_PFSTRAN_MASTER 0x60
1108 #define HAMMER2_PFSTRAN_UNUSED70 0x70
1109 #define HAMMER2_PFSTRAN_SUPROOT 0x80
1110 #define HAMMER2_PFSTRAN_DUMMY 0x90
1112 #define HAMMER2_PFS_DEC(n) ((n) & 0x0F)
1113 #define HAMMER2_PFS_DEC_TRANSITION(n) (((n) >> 4) & 0x0F)
1114 #define HAMMER2_PFS_ENC_TRANSITION(n) (((n) & 0x0F) << 4)
1116 #define HAMMER2_PFSSUBTYPE_NONE 0
1117 #define HAMMER2_PFSSUBTYPE_SNAPSHOT 1 /* manual/managed snapshot */
1118 #define HAMMER2_PFSSUBTYPE_AUTOSNAP 2 /* automatic snapshot */
1121 * PFS mode of operation is a bitmask. This is typically not stored
1122 * on-media, but defined here because the field may be used in dmsgs.
1124 #define HAMMER2_PFSMODE_QUORUM 0x01
1125 #define HAMMER2_PFSMODE_RW 0x02
1134 * Flags (8 bits) - blockref, for freemap only
1136 * Note that the minimum chunk size is 1KB so we could theoretically have
1137 * 10 bits here, but we might have some future extension that allows a
1138 * chunk size down to 256 bytes and if so we will need bits 8 and 9.
1140 #define HAMMER2_AVF_SELMASK 0x03 /* select group */
1141 #define HAMMER2_AVF_ALL_ALLOC 0x04 /* indicate all allocated */
1142 #define HAMMER2_AVF_ALL_FREE 0x08 /* indicate all free */
1143 #define HAMMER2_AVF_RESERVED10 0x10
1144 #define HAMMER2_AVF_RESERVED20 0x20
1145 #define HAMMER2_AVF_RESERVED40 0x40
1146 #define HAMMER2_AVF_RESERVED80 0x80
1147 #define HAMMER2_AVF_AVMASK32 ((uint32_t)0xFFFFFF00LU)
1148 #define HAMMER2_AVF_AVMASK64 ((uint64_t)0xFFFFFFFFFFFFFF00LLU)
1150 #define HAMMER2_AV_SELECT_A 0x00
1151 #define HAMMER2_AV_SELECT_B 0x01
1152 #define HAMMER2_AV_SELECT_C 0x02
1153 #define HAMMER2_AV_SELECT_D 0x03
1156 * The volume header eats a 64K block. There is currently an issue where
1157 * we want to try to fit all nominal filesystem updates in a 512-byte section
1158 * but it may be a lost cause due to the need for a blockset.
1160 * All information is stored in host byte order. The volume header's magic
1161 * number may be checked to determine the byte order. If you wish to mount
1162 * between machines w/ different endian modes you'll need filesystem code
1163 * which acts on the media data consistently (either all one way or all the
1164 * other). Our code currently does not do that.
1166 * A read-write mount may have to recover missing allocations by doing an
1167 * incremental mirror scan looking for modifications made after alloc_tid.
1168 * If alloc_tid == last_tid then no recovery operation is needed. Recovery
1169 * operations are usually very, very fast.
1171 * Read-only mounts do not need to do any recovery, access to the filesystem
1172 * topology is always consistent after a crash (is always consistent, period).
1173 * However, there may be shortcutted blockref updates present from deep in
1174 * the tree which are stored in the volumeh eader and must be tracked on
1177 * NOTE: The copyinfo[] array contains the configuration for both the
1178 * cluster connections and any local media copies. The volume
1179 * header will be replicated for each local media copy.
1181 * The mount command may specify multiple medias or just one and
1182 * allow HAMMER2 to pick up the others when it checks the copyinfo[]
1185 * NOTE: root_blockref points to the super-root directory, not the root
1186 * directory. The root directory will be a subdirectory under the
1189 * The super-root directory contains all root directories and all
1190 * snapshots (readonly or writable). It is possible to do a
1191 * null-mount of the super-root using special path constructions
1192 * relative to your mounted root.
1194 * NOTE: HAMMER2 allows any subdirectory tree to be managed as if it were
1195 * a PFS, including mirroring and storage quota operations, and this is
1196 * prefered over creating discrete PFSs in the super-root. Instead
1197 * the super-root is most typically used to create writable snapshots,
1198 * alternative roots, and so forth. The super-root is also used by
1199 * the automatic snapshotting mechanism.
1201 #define HAMMER2_VOLUME_ID_HBO 0x48414d3205172011LLU
1202 #define HAMMER2_VOLUME_ID_ABO 0x11201705324d4148LLU
1204 struct hammer2_volume_data {
1206 * sector #0 - 512 bytes
1208 uint64_t magic; /* 0000 Signature */
1209 hammer2_off_t boot_beg; /* 0008 Boot area (future) */
1210 hammer2_off_t boot_end; /* 0010 (size = end - beg) */
1211 hammer2_off_t aux_beg; /* 0018 Aux area (future) */
1212 hammer2_off_t aux_end; /* 0020 (size = end - beg) */
1213 hammer2_off_t volu_size; /* 0028 Volume size, bytes */
1215 uint32_t version; /* 0030 */
1216 uint32_t flags; /* 0034 */
1217 uint8_t copyid; /* 0038 copyid of phys vol */
1218 uint8_t freemap_version; /* 0039 freemap algorithm */
1219 uint8_t peer_type; /* 003A HAMMER2_PEER_xxx */
1220 uint8_t reserved003B; /* 003B */
1221 uint32_t reserved003C; /* 003C */
1223 uuid_t fsid; /* 0040 */
1224 uuid_t fstype; /* 0050 */
1227 * allocator_size is precalculated at newfs time and does not include
1228 * reserved blocks, boot, or redo areas.
1230 * Initial non-reserved-area allocations do not use the freemap
1231 * but instead adjust alloc_iterator. Dynamic allocations take
1232 * over starting at (allocator_beg). This makes newfs_hammer2's
1233 * job a lot easier and can also serve as a testing jig.
1235 hammer2_off_t allocator_size; /* 0060 Total data space */
1236 hammer2_off_t allocator_free; /* 0068 Free space */
1237 hammer2_off_t allocator_beg; /* 0070 Initial allocations */
1240 * mirror_tid reflects the highest committed change for this
1241 * block device regardless of whether it is to the super-root
1242 * or to a PFS or whatever.
1244 * freemap_tid reflects the highest committed freemap change for
1245 * this block device.
1247 hammer2_tid_t mirror_tid; /* 0078 committed tid (vol) */
1248 hammer2_tid_t reserved0080; /* 0080 */
1249 hammer2_tid_t reserved0088; /* 0088 */
1250 hammer2_tid_t freemap_tid; /* 0090 committed tid (fmap) */
1251 hammer2_tid_t bulkfree_tid; /* 0098 bulkfree incremental */
1252 hammer2_tid_t reserved00A0[5]; /* 00A0-00C7 */
1255 * Copyids are allocated dynamically from the copyexists bitmap.
1256 * An id from the active copies set (up to 8, see copyinfo later on)
1257 * may still exist after the copy set has been removed from the
1258 * volume header and its bit will remain active in the bitmap and
1259 * cannot be reused until it is 100% removed from the hierarchy.
1261 uint32_t copyexists[8]; /* 00C8-00E7 copy exists bmap */
1262 char reserved0140[248]; /* 00E8-01DF */
1265 * 32 bit CRC array at the end of the first 512 byte sector.
1267 * icrc_sects[7] - First 512-4 bytes of volume header (including all
1268 * the other icrc's except this one).
1270 * icrc_sects[6] - Sector 1 (512 bytes) of volume header, which is
1271 * the blockset for the root.
1273 * icrc_sects[5] - Sector 2
1274 * icrc_sects[4] - Sector 3
1275 * icrc_sects[3] - Sector 4 (the freemap blockset)
1277 hammer2_crc32_t icrc_sects[8]; /* 01E0-01FF */
1280 * sector #1 - 512 bytes
1282 * The entire sector is used by a blockset.
1284 hammer2_blockset_t sroot_blockset; /* 0200-03FF Superroot dir */
1289 char sector2[512]; /* 0400-05FF reserved */
1290 char sector3[512]; /* 0600-07FF reserved */
1291 hammer2_blockset_t freemap_blockset; /* 0800-09FF freemap */
1292 char sector5[512]; /* 0A00-0BFF reserved */
1293 char sector6[512]; /* 0C00-0DFF reserved */
1294 char sector7[512]; /* 0E00-0FFF reserved */
1297 * sector #8-71 - 32768 bytes
1299 * Contains the configuration for up to 256 copyinfo targets. These
1300 * specify local and remote copies operating as masters or slaves.
1301 * copyid's 0 and 255 are reserved (0 indicates an empty slot and 255
1302 * indicates the local media).
1304 * Each inode contains a set of up to 8 copyids, either inherited
1305 * from its parent or explicitly specified in the inode, which
1306 * indexes into this array.
1308 /* 1000-8FFF copyinfo config */
1309 hammer2_volconf_t copyinfo[HAMMER2_COPYID_COUNT];
1312 * Remaining sections are reserved for future use.
1314 char reserved0400[0x6FFC]; /* 9000-FFFB reserved */
1317 * icrc on entire volume header
1319 hammer2_crc32_t icrc_volheader; /* FFFC-FFFF full volume icrc*/
1322 typedef struct hammer2_volume_data hammer2_volume_data_t;
1325 * Various parts of the volume header have their own iCRCs.
1327 * The first 512 bytes has its own iCRC stored at the end of the 512 bytes
1328 * and not included the icrc calculation.
1330 * The second 512 bytes also has its own iCRC but it is stored in the first
1331 * 512 bytes so it covers the entire second 512 bytes.
1333 * The whole volume block (64KB) has an iCRC covering all but the last 4 bytes,
1334 * which is where the iCRC for the whole volume is stored. This is currently
1335 * a catch-all for anything not individually iCRCd.
1337 #define HAMMER2_VOL_ICRC_SECT0 7
1338 #define HAMMER2_VOL_ICRC_SECT1 6
1340 #define HAMMER2_VOLUME_BYTES 65536
1342 #define HAMMER2_VOLUME_ICRC0_OFF 0
1343 #define HAMMER2_VOLUME_ICRC1_OFF 512
1344 #define HAMMER2_VOLUME_ICRCVH_OFF 0
1346 #define HAMMER2_VOLUME_ICRC0_SIZE (512 - 4)
1347 #define HAMMER2_VOLUME_ICRC1_SIZE (512)
1348 #define HAMMER2_VOLUME_ICRCVH_SIZE (65536 - 4)
1350 #define HAMMER2_VOL_VERSION_MIN 1
1351 #define HAMMER2_VOL_VERSION_DEFAULT 1
1352 #define HAMMER2_VOL_VERSION_WIP 2
1354 #define HAMMER2_NUM_VOLHDRS 4
1356 union hammer2_media_data {
1357 hammer2_volume_data_t voldata;
1358 hammer2_inode_data_t ipdata;
1359 hammer2_blockset_t blkset;
1360 hammer2_blockref_t npdata[HAMMER2_IND_COUNT_MAX];
1361 hammer2_bmap_data_t bmdata[HAMMER2_FREEMAP_COUNT];
1362 char buf[HAMMER2_PBUFSIZE];
1365 typedef union hammer2_media_data hammer2_media_data_t;
1367 #endif /* !_VFS_HAMMER2_DISK_H_ */