2 * Copyright (c) 2007 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
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8 * modification, are permitted provided that the following conditions
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15 * the documentation and/or other materials provided with the
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18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
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24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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34 * $DragonFly: src/sys/vfs/hammer/hammer_disk.h,v 1.55 2008/11/13 02:18:43 dillon Exp $
37 #ifndef VFS_HAMMER_DISK_H_
38 #define VFS_HAMMER_DISK_H_
45 * The structures below represent the on-disk format for a HAMMER
46 * filesystem. Note that all fields for on-disk structures are naturally
47 * aligned. The host endian format is used - compatibility is possible
48 * if the implementation detects reversed endian and adjusts data accordingly.
50 * Most of HAMMER revolves around the concept of an object identifier. An
51 * obj_id is a 64 bit quantity which uniquely identifies a filesystem object
52 * FOR THE ENTIRE LIFE OF THE FILESYSTEM. This uniqueness allows backups
53 * and mirrors to retain varying amounts of filesystem history by removing
54 * any possibility of conflict through identifier reuse.
56 * A HAMMER filesystem may span multiple volumes.
58 * A HAMMER filesystem uses a 16K filesystem buffer size. All filesystem
59 * I/O is done in multiples of 16K.
61 * 64K X-bufs are used for blocks >= a file's 1MB mark.
63 * Per-volume storage limit: 52 bits 4096 TB
64 * Per-Zone storage limit: 60 bits 1 MTB
65 * Per-filesystem storage limit: 60 bits 1 MTB
67 #define HAMMER_BUFSIZE 16384
68 #define HAMMER_XBUFSIZE 65536
69 #define HAMMER_HBUFSIZE (HAMMER_BUFSIZE / 2)
70 #define HAMMER_XDEMARC (1024 * 1024)
71 #define HAMMER_BUFMASK (HAMMER_BUFSIZE - 1)
72 #define HAMMER_XBUFMASK (HAMMER_XBUFSIZE - 1)
74 #define HAMMER_BUFSIZE64 ((u_int64_t)HAMMER_BUFSIZE)
75 #define HAMMER_BUFMASK64 ((u_int64_t)HAMMER_BUFMASK)
77 #define HAMMER_XBUFSIZE64 ((u_int64_t)HAMMER_XBUFSIZE)
78 #define HAMMER_XBUFMASK64 ((u_int64_t)HAMMER_XBUFMASK)
80 #define HAMMER_OFF_ZONE_MASK 0xF000000000000000ULL /* zone portion */
81 #define HAMMER_OFF_VOL_MASK 0x0FF0000000000000ULL /* volume portion */
82 #define HAMMER_OFF_SHORT_MASK 0x000FFFFFFFFFFFFFULL /* offset portion */
83 #define HAMMER_OFF_LONG_MASK 0x0FFFFFFFFFFFFFFFULL /* offset portion */
85 #define HAMMER_OFF_BAD ((hammer_off_t)-1)
88 * The current limit of volumes that can make up a HAMMER FS
90 #define HAMMER_MAX_VOLUMES 256
93 * Hammer transaction ids are 64 bit unsigned integers and are usually
94 * synchronized with the time of day in nanoseconds.
96 * Hammer offsets are used for FIFO indexing and embed a cycle counter
97 * and volume number in addition to the offset. Most offsets are required
98 * to be 16 KB aligned.
100 typedef u_int64_t hammer_tid_t;
101 typedef u_int64_t hammer_off_t;
102 typedef u_int32_t hammer_crc_t;
104 #define HAMMER_MIN_TID 0ULL /* unsigned */
105 #define HAMMER_MAX_TID 0xFFFFFFFFFFFFFFFFULL /* unsigned */
106 #define HAMMER_MIN_KEY -0x8000000000000000LL /* signed */
107 #define HAMMER_MAX_KEY 0x7FFFFFFFFFFFFFFFLL /* signed */
108 #define HAMMER_MIN_OBJID HAMMER_MIN_KEY /* signed */
109 #define HAMMER_MAX_OBJID HAMMER_MAX_KEY /* signed */
110 #define HAMMER_MIN_RECTYPE 0x0U /* unsigned */
111 #define HAMMER_MAX_RECTYPE 0xFFFFU /* unsigned */
112 #define HAMMER_MIN_OFFSET 0ULL /* unsigned */
113 #define HAMMER_MAX_OFFSET 0xFFFFFFFFFFFFFFFFULL /* unsigned */
116 * hammer_off_t has several different encodings. Note that not all zones
119 * zone 0: reserved for sanity
120 * zone 1 (z,v,o): raw volume relative (offset 0 is the volume header)
121 * zone 2 (z,v,o): raw buffer relative (offset 0 is the first buffer)
122 * zone 3 (z,o): undo fifo - actually zone-2 address, fixed phys array in vol hdr
123 * zone 4 (z,v,o): freemap - only real blockmap
124 * zone 8 (z,v,o): B-Tree - actually zone-2 address
125 * zone 9 (z,v,o): meta - actually zone-2 address
126 * zone 10 (z,v,o): large-data - actually zone-2 address
127 * zone 11 (z,v,o): small-data - actually zone-2 address
128 * zone 15: reserved for sanity
130 * layer1/layer2 direct map:
131 * zzzzvvvvvvvvoooo oooooooooooooooo oooooooooooooooo oooooooooooooooo
132 * ----111111111111 1111112222222222 222222222ooooooo oooooooooooooooo
135 #define HAMMER_ZONE_RAW_VOLUME 0x1000000000000000ULL
136 #define HAMMER_ZONE_RAW_BUFFER 0x2000000000000000ULL
137 #define HAMMER_ZONE_UNDO 0x3000000000000000ULL
138 #define HAMMER_ZONE_FREEMAP 0x4000000000000000ULL
139 #define HAMMER_ZONE_RESERVED05 0x5000000000000000ULL
140 #define HAMMER_ZONE_RESERVED06 0x6000000000000000ULL
141 #define HAMMER_ZONE_RESERVED07 0x7000000000000000ULL
142 #define HAMMER_ZONE_BTREE 0x8000000000000000ULL
143 #define HAMMER_ZONE_META 0x9000000000000000ULL
144 #define HAMMER_ZONE_LARGE_DATA 0xA000000000000000ULL
145 #define HAMMER_ZONE_SMALL_DATA 0xB000000000000000ULL
146 #define HAMMER_ZONE_RESERVED0C 0xC000000000000000ULL
147 #define HAMMER_ZONE_RESERVED0D 0xD000000000000000ULL
148 #define HAMMER_ZONE_RESERVED0E 0xE000000000000000ULL
149 #define HAMMER_ZONE_UNAVAIL 0xF000000000000000ULL
151 #define HAMMER_ZONE_RAW_VOLUME_INDEX 1
152 #define HAMMER_ZONE_RAW_BUFFER_INDEX 2
153 #define HAMMER_ZONE_UNDO_INDEX 3
154 #define HAMMER_ZONE_FREEMAP_INDEX 4
155 #define HAMMER_ZONE_BTREE_INDEX 8
156 #define HAMMER_ZONE_META_INDEX 9
157 #define HAMMER_ZONE_LARGE_DATA_INDEX 10
158 #define HAMMER_ZONE_SMALL_DATA_INDEX 11
159 #define HAMMER_ZONE_UNAVAIL_INDEX 15 /* unavailable */
161 #define HAMMER_MAX_ZONES 16
164 * Backend zones that are mapped to zone-2 (except for zone-3)
165 * starts from this index which is 8.
167 #define HAMMER_ZONE2_MAPPED_INDEX HAMMER_ZONE_BTREE_INDEX
169 #define HAMMER_ZONE_ENCODE(zone, ham_off) \
170 (((hammer_off_t)(zone) << 60) | (ham_off))
171 #define HAMMER_ZONE_DECODE(ham_off) \
172 (int32_t)(((hammer_off_t)(ham_off) >> 60))
174 #define HAMMER_VOL_ENCODE(vol_no) \
175 ((hammer_off_t)((vol_no) & 255) << 52)
176 #define HAMMER_VOL_DECODE(ham_off) \
177 (int32_t)(((hammer_off_t)(ham_off) >> 52) & 255)
179 #define HAMMER_OFF_SHORT_ENCODE(offset) \
180 ((hammer_off_t)(offset) & HAMMER_OFF_SHORT_MASK)
181 #define HAMMER_OFF_LONG_ENCODE(offset) \
182 ((hammer_off_t)(offset) & HAMMER_OFF_LONG_MASK)
184 #define HAMMER_ENCODE(zone, vol_no, offset) \
185 (((hammer_off_t)(zone) << 60) | \
186 HAMMER_VOL_ENCODE(vol_no) | \
187 HAMMER_OFF_SHORT_ENCODE(offset))
188 #define HAMMER_ENCODE_RAW_VOLUME(vol_no, offset) \
189 HAMMER_ENCODE(HAMMER_ZONE_RAW_VOLUME_INDEX, vol_no, offset)
190 #define HAMMER_ENCODE_RAW_BUFFER(vol_no, offset) \
191 HAMMER_ENCODE(HAMMER_ZONE_RAW_BUFFER_INDEX, vol_no, offset)
192 #define HAMMER_ENCODE_FREEMAP(vol_no, offset) \
193 HAMMER_ENCODE(HAMMER_ZONE_FREEMAP_INDEX, vol_no, offset)
196 * Translate a zone address to zone-X address.
198 #define hammer_xlate_to_zoneX(zone, offset) \
199 HAMMER_ZONE_ENCODE((zone), (offset) & ~HAMMER_OFF_ZONE_MASK)
200 #define hammer_xlate_to_zone2(offset) \
201 hammer_xlate_to_zoneX(HAMMER_ZONE_RAW_BUFFER_INDEX, (offset))
203 #define hammer_data_zone(data_len) \
204 (((data_len) >= HAMMER_BUFSIZE) ? \
205 HAMMER_ZONE_LARGE_DATA : \
206 HAMMER_ZONE_SMALL_DATA)
207 #define hammer_data_zone_index(data_len) \
208 (((data_len) >= HAMMER_BUFSIZE) ? \
209 HAMMER_ZONE_LARGE_DATA_INDEX : \
210 HAMMER_ZONE_SMALL_DATA_INDEX)
213 * Big-Block backing store
215 * A blockmap is a two-level map which translates a blockmap-backed zone
216 * offset into a raw zone 2 offset. The layer 1 handles 18 bits and the
217 * layer 2 handles 19 bits. The 8M big-block size is 23 bits so two
218 * layers gives us 18+19+23 = 60 bits of address space.
220 * When using hinting for a blockmap lookup, the hint is lost when the
221 * scan leaves the HINTBLOCK, which is typically several BIGBLOCK's.
222 * HINTBLOCK is a heuristic.
224 #define HAMMER_HINTBLOCK_SIZE (HAMMER_BIGBLOCK_SIZE * 4)
225 #define HAMMER_HINTBLOCK_MASK64 ((u_int64_t)HAMMER_HINTBLOCK_SIZE - 1)
226 #define HAMMER_BIGBLOCK_SIZE (8192 * 1024)
227 #define HAMMER_BIGBLOCK_OVERFILL (6144 * 1024)
228 #define HAMMER_BIGBLOCK_SIZE64 ((u_int64_t)HAMMER_BIGBLOCK_SIZE)
229 #define HAMMER_BIGBLOCK_MASK (HAMMER_BIGBLOCK_SIZE - 1)
230 #define HAMMER_BIGBLOCK_MASK64 ((u_int64_t)HAMMER_BIGBLOCK_SIZE - 1)
231 #define HAMMER_BIGBLOCK_BITS 23
232 #if (1 << HAMMER_BIGBLOCK_BITS) != HAMMER_BIGBLOCK_SIZE
233 #error "HAMMER_BIGBLOCK_BITS BROKEN"
236 #define HAMMER_BUFFERS_PER_BIGBLOCK \
237 (HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE)
238 #define HAMMER_BUFFERS_PER_BIGBLOCK_MASK \
239 (HAMMER_BUFFERS_PER_BIGBLOCK - 1)
240 #define HAMMER_BUFFERS_PER_BIGBLOCK_MASK64 \
241 ((hammer_off_t)HAMMER_BUFFERS_PER_BIGBLOCK_MASK)
244 * Maximum number of mirrors operating in master mode (multi-master
245 * clustering and mirroring). Note that HAMMER1 does not support
246 * multi-master clustering as of 2015.
248 #define HAMMER_MAX_MASTERS 16
251 * The blockmap is somewhat of a degenerate structure. HAMMER only actually
252 * uses it in its original incarnation to implement the freemap.
254 * zone:1 raw volume (no blockmap)
255 * zone:2 raw buffer (no blockmap)
256 * zone:3 undomap (direct layer2 array in volume header)
257 * zone:4 freemap (the only real blockmap)
258 * zone:8-15 zone id used to classify big-block only, address is actually
261 struct hammer_blockmap {
262 hammer_off_t phys_offset; /* zone-2 physical offset */
263 hammer_off_t first_offset; /* zone-X logical offset (zone 3) */
264 hammer_off_t next_offset; /* zone-X logical offset */
265 hammer_off_t alloc_offset; /* zone-X logical offset */
266 u_int32_t reserved01;
267 hammer_crc_t entry_crc;
270 typedef struct hammer_blockmap *hammer_blockmap_t;
272 #define HAMMER_BLOCKMAP_CRCSIZE \
273 offsetof(struct hammer_blockmap, entry_crc)
276 * The blockmap is a 2-layer entity made up of big-blocks. The first layer
277 * contains 262144 32-byte entries (18 bits), the second layer contains
278 * 524288 16-byte entries (19 bits), representing 8MB (23 bit) blockmaps.
279 * 18+19+23 = 60 bits. The top four bits are the zone id.
281 * Currently only the freemap utilizes both layers in all their glory.
282 * All primary data/meta-data zones actually encode a zone-2 address
283 * requiring no real blockmap translation.
285 * The freemap uses the upper 8 bits of layer-1 to identify the volume,
286 * thus any space allocated via the freemap can be directly translated
287 * to a zone:2 (or zone:8-15) address.
289 * zone-X blockmap offset: [zone:4][layer1:18][layer2:19][big-block:23]
291 struct hammer_blockmap_layer1 {
292 hammer_off_t blocks_free; /* big-blocks free */
293 hammer_off_t phys_offset; /* UNAVAIL or zone-2 */
294 hammer_off_t reserved01;
295 hammer_crc_t layer2_crc; /* xor'd crc's of HAMMER_BLOCKSIZE */
297 hammer_crc_t layer1_crc; /* MUST BE LAST FIELD OF STRUCTURE*/
300 typedef struct hammer_blockmap_layer1 *hammer_blockmap_layer1_t;
302 #define HAMMER_LAYER1_CRCSIZE \
303 offsetof(struct hammer_blockmap_layer1, layer1_crc)
306 * layer2 entry for 8MB big-block.
308 * NOTE: bytes_free is signed and can legally go negative if/when data
309 * de-dup occurs. This field will never go higher than
310 * HAMMER_BIGBLOCK_SIZE. If exactly HAMMER_BIGBLOCK_SIZE
311 * the big-block is completely free.
313 struct hammer_blockmap_layer2 {
314 u_int8_t zone; /* typed allocation zone */
317 u_int32_t append_off; /* allocatable space index */
318 int32_t bytes_free; /* bytes free within this big-block */
319 hammer_crc_t entry_crc;
322 typedef struct hammer_blockmap_layer2 *hammer_blockmap_layer2_t;
324 #define HAMMER_LAYER2_CRCSIZE \
325 offsetof(struct hammer_blockmap_layer2, entry_crc)
327 #define HAMMER_BLOCKMAP_UNAVAIL ((hammer_off_t)-1LL)
329 #define HAMMER_BLOCKMAP_RADIX1 /* 262144 (18) */ \
330 (HAMMER_BIGBLOCK_SIZE / sizeof(struct hammer_blockmap_layer1))
331 #define HAMMER_BLOCKMAP_RADIX2 /* 524288 (19) */ \
332 (HAMMER_BIGBLOCK_SIZE / sizeof(struct hammer_blockmap_layer2))
334 #define HAMMER_BLOCKMAP_RADIX1_PERBUFFER \
335 (HAMMER_BLOCKMAP_RADIX1 / HAMMER_BUFFERS_PER_BIGBLOCK)
336 #define HAMMER_BLOCKMAP_RADIX2_PERBUFFER \
337 (HAMMER_BLOCKMAP_RADIX2 / HAMMER_BUFFERS_PER_BIGBLOCK)
339 #define HAMMER_BLOCKMAP_LAYER1 /* 18+19+23 - 1EB */ \
340 (HAMMER_BLOCKMAP_RADIX1 * HAMMER_BLOCKMAP_LAYER2)
341 #define HAMMER_BLOCKMAP_LAYER2 /* 19+23 - 4TB */ \
342 (HAMMER_BLOCKMAP_RADIX2 * HAMMER_BIGBLOCK_SIZE64)
344 #define HAMMER_BLOCKMAP_LAYER1_MASK (HAMMER_BLOCKMAP_LAYER1 - 1)
345 #define HAMMER_BLOCKMAP_LAYER2_MASK (HAMMER_BLOCKMAP_LAYER2 - 1)
348 * Index within layer1 or layer2 big-block for the entry representing
349 * a zone-2 physical offset.
351 #define HAMMER_BLOCKMAP_LAYER1_INDEX(zone2_offset) \
352 (((zone2_offset) & HAMMER_BLOCKMAP_LAYER1_MASK) / \
353 HAMMER_BLOCKMAP_LAYER2)
355 #define HAMMER_BLOCKMAP_LAYER2_INDEX(zone2_offset) \
356 (((zone2_offset) & HAMMER_BLOCKMAP_LAYER2_MASK) / \
357 HAMMER_BIGBLOCK_SIZE64)
360 * Byte offset within layer1 or layer2 big-block for the entry representing
361 * a zone-2 physical offset. Multiply the index by sizeof(blockmap_layer).
363 #define HAMMER_BLOCKMAP_LAYER1_OFFSET(zone2_offset) \
364 (HAMMER_BLOCKMAP_LAYER1_INDEX(zone2_offset) * \
365 sizeof(struct hammer_blockmap_layer1))
367 #define HAMMER_BLOCKMAP_LAYER2_OFFSET(zone2_offset) \
368 (HAMMER_BLOCKMAP_LAYER2_INDEX(zone2_offset) * \
369 sizeof(struct hammer_blockmap_layer2))
372 * HAMMER UNDO parameters. The UNDO fifo is mapped directly in the volume
373 * header with an array of layer2 structures. A maximum of (128x8MB) = 1GB
374 * may be reserved. The size of the undo fifo is usually set a newfs time
375 * but can be adjusted if the filesystem is taken offline.
377 #define HAMMER_UNDO_LAYER2 128 /* max layer2 undo mapping entries */
380 * All on-disk HAMMER structures which make up elements of the UNDO FIFO
381 * contain a hammer_fifo_head and hammer_fifo_tail structure. This structure
382 * contains all the information required to validate the fifo element
383 * and to scan the fifo in either direction. The head is typically embedded
384 * in higher level hammer on-disk structures while the tail is typically
385 * out-of-band. hdr_size is the size of the whole mess, including the tail.
387 * All undo structures are guaranteed to not cross a 16K filesystem
388 * buffer boundary. Most undo structures are fairly small. Data spaces
389 * are not immediately reused by HAMMER so file data is not usually recorded
390 * as part of an UNDO.
392 * PAD elements are allowed to take up only 8 bytes of space as a special
393 * case, containing only hdr_signature, hdr_type, and hdr_size fields,
394 * and with the tail overloaded onto the head structure for 8 bytes total.
396 * Every undo record has a sequence number. This number is unrelated to
397 * transaction ids and instead collects the undo transactions associated
398 * with a single atomic operation. A larger transactional operation, such
399 * as a remove(), may consist of several smaller atomic operations
400 * representing raw meta-data operations.
402 * HAMMER VERSION 4 CHANGES
404 * In HAMMER version 4 the undo structure alignment is reduced from 16384
405 * to 512 bytes in order to ensure that each 512 byte sector begins with
406 * a header. The reserved01 field in the header is now a 32 bit sequence
407 * number. This allows the recovery code to detect missing sectors
408 * without relying on the 32-bit crc and to definitively identify the current
409 * undo sequence space without having to rely on information from the volume
410 * header. In addition, new REDO entries in the undo space are used to
411 * record write, write/extend, and transaction id updates.
413 * The grand result is:
415 * (1) The volume header no longer needs to be synchronized for most
416 * flush and fsync operations.
418 * (2) Most fsync operations need only lay down REDO records
420 * (3) Data overwrite for nohistory operations covered by REDO records
421 * can be supported (instead of rolling a new block allocation),
422 * by rolling UNDO for the prior contents of the data.
424 * HAMMER VERSION 5 CHANGES
426 * Hammer version 5 contains a minor adjustment making layer2's bytes_free
427 * field signed, allowing dedup to push it into the negative domain.
429 #define HAMMER_HEAD_ALIGN 8
430 #define HAMMER_HEAD_ALIGN_MASK (HAMMER_HEAD_ALIGN - 1)
431 #define HAMMER_HEAD_DOALIGN(bytes) \
432 (((bytes) + HAMMER_HEAD_ALIGN_MASK) & ~HAMMER_HEAD_ALIGN_MASK)
434 #define HAMMER_UNDO_ALIGN 512
435 #define HAMMER_UNDO_ALIGN64 ((u_int64_t)512)
436 #define HAMMER_UNDO_MASK (HAMMER_UNDO_ALIGN - 1)
437 #define HAMMER_UNDO_MASK64 (HAMMER_UNDO_ALIGN64 - 1)
439 struct hammer_fifo_head {
440 u_int16_t hdr_signature;
442 u_int32_t hdr_size; /* Aligned size of the whole mess */
443 u_int32_t hdr_seq; /* Sequence number */
444 hammer_crc_t hdr_crc; /* XOR crc up to field w/ crc after field */
447 #define HAMMER_FIFO_HEAD_CRCOFF offsetof(struct hammer_fifo_head, hdr_crc)
449 struct hammer_fifo_tail {
450 u_int16_t tail_signature;
452 u_int32_t tail_size; /* aligned size of the whole mess */
455 typedef struct hammer_fifo_head *hammer_fifo_head_t;
456 typedef struct hammer_fifo_tail *hammer_fifo_tail_t;
461 #define HAMMER_HEAD_TYPE_PAD (0x0040U|HAMMER_HEAD_FLAG_FREE)
462 #define HAMMER_HEAD_TYPE_DUMMY 0x0041U /* dummy entry w/seqno */
463 #define HAMMER_HEAD_TYPE_42 0x0042U
464 #define HAMMER_HEAD_TYPE_UNDO 0x0043U /* random UNDO information */
465 #define HAMMER_HEAD_TYPE_REDO 0x0044U /* data REDO / fast fsync */
466 #define HAMMER_HEAD_TYPE_45 0x0045U
468 #define HAMMER_HEAD_FLAG_FREE 0x8000U /* Indicates object freed */
470 #define HAMMER_HEAD_SIGNATURE 0xC84EU
471 #define HAMMER_TAIL_SIGNATURE 0xC74FU
474 * Misc FIFO structures.
476 * UNDO - Raw meta-data media updates.
478 struct hammer_fifo_undo {
479 struct hammer_fifo_head head;
480 hammer_off_t undo_offset; /* zone-1,2 offset */
481 int32_t undo_data_bytes;
482 int32_t undo_reserved01;
483 /* followed by data */
487 * REDO (HAMMER version 4+) - Logical file writes/truncates.
489 * REDOs contain information which will be duplicated in a later meta-data
490 * update, allowing fast write()+fsync() operations. REDOs can be ignored
491 * without harming filesystem integrity but must be processed if fsync()
492 * semantics are desired.
494 * Unlike UNDOs which are processed backwards within the recovery span,
495 * REDOs must be processed forwards starting further back (starting outside
496 * the recovery span).
498 * WRITE - Write logical file (with payload). Executed both
499 * out-of-span and in-span. Out-of-span WRITEs may be
500 * filtered out by TERMs.
502 * TRUNC - Truncate logical file (no payload). Executed both
503 * out-of-span and in-span. Out-of-span WRITEs may be
504 * filtered out by TERMs.
506 * TERM_* - Indicates meta-data was committed (if out-of-span) or
507 * will be rolled-back (in-span). Any out-of-span TERMs
508 * matching earlier WRITEs remove those WRITEs from
509 * consideration as they might conflict with a later data
510 * commit (which is not being rolled-back).
512 * SYNC - The earliest in-span SYNC (the last one when scanning
513 * backwards) tells the recovery code how far out-of-span
514 * it must go to run REDOs.
516 * NOTE: WRITEs do not always have matching TERMs even under
517 * perfect conditions because truncations might remove the
518 * buffers from consideration. I/O problems can also remove
519 * buffers from consideration.
521 * TRUNCSs do not always have matching TERMs because several
522 * truncations may be aggregated together into a single TERM.
524 struct hammer_fifo_redo {
525 struct hammer_fifo_head head;
526 int64_t redo_objid; /* file being written */
527 hammer_off_t redo_offset; /* logical offset in file */
528 int32_t redo_data_bytes;
529 u_int32_t redo_flags;
530 u_int32_t redo_localization;
531 u_int32_t redo_reserved;
532 u_int64_t redo_mtime; /* set mtime */
535 #define HAMMER_REDO_WRITE 0x00000001
536 #define HAMMER_REDO_TRUNC 0x00000002
537 #define HAMMER_REDO_TERM_WRITE 0x00000004
538 #define HAMMER_REDO_TERM_TRUNC 0x00000008
539 #define HAMMER_REDO_SYNC 0x00000010
541 union hammer_fifo_any {
542 struct hammer_fifo_head head;
543 struct hammer_fifo_undo undo;
544 struct hammer_fifo_redo redo;
547 typedef struct hammer_fifo_redo *hammer_fifo_redo_t;
548 typedef struct hammer_fifo_undo *hammer_fifo_undo_t;
549 typedef union hammer_fifo_any *hammer_fifo_any_t;
552 * Volume header types
554 #define HAMMER_FSBUF_VOLUME 0xC8414D4DC5523031ULL /* HAMMER01 */
555 #define HAMMER_FSBUF_VOLUME_REV 0x313052C54D4D41C8ULL /* (reverse endian) */
558 * HAMMER Volume header
560 * A HAMMER filesystem is built from any number of block devices, Each block
561 * device contains a volume header followed by however many buffers fit
564 * One of the volumes making up a HAMMER filesystem is the master, the
565 * rest are slaves. It does not have to be volume #0.
567 * The volume header takes up an entire 16K filesystem buffer and may
568 * represent up to 64KTB (65536 TB) of space.
570 * Special field notes:
572 * vol_bot_beg - offset of boot area (mem_beg - bot_beg bytes)
573 * vol_mem_beg - offset of memory log (clu_beg - mem_beg bytes)
574 * vol_buf_beg - offset of the first buffer.
576 * The memory log area allows a kernel to cache new records and data
577 * in memory without allocating space in the actual filesystem to hold
578 * the records and data. In the event that a filesystem becomes full,
579 * any records remaining in memory can be flushed to the memory log
580 * area. This allows the kernel to immediately return success.
583 #define HAMMER_BOOT_MINBYTES (32*1024)
584 #define HAMMER_BOOT_NOMBYTES (64LL*1024*1024)
585 #define HAMMER_BOOT_MAXBYTES (256LL*1024*1024)
587 #define HAMMER_MEM_MINBYTES (256*1024)
588 #define HAMMER_MEM_NOMBYTES (1LL*1024*1024*1024)
589 #define HAMMER_MEM_MAXBYTES (64LL*1024*1024*1024)
591 struct hammer_volume_ondisk {
592 u_int64_t vol_signature;/* Signature */
594 int64_t vol_bot_beg; /* byte offset of boot area or 0 */
595 int64_t vol_mem_beg; /* byte offset of memory log or 0 */
596 int64_t vol_buf_beg; /* byte offset of first buffer in volume */
597 int64_t vol_buf_end; /* byte offset of volume EOF (on buf bndry) */
598 int64_t vol_locked; /* not used */
600 uuid_t vol_fsid; /* identify filesystem */
601 uuid_t vol_fstype; /* identify filesystem type */
602 char vol_name[64]; /* filesystem label */
604 int32_t vol_no; /* volume number within filesystem */
605 int32_t vol_count; /* number of volumes making up FS */
607 u_int32_t vol_version; /* version control information */
608 hammer_crc_t vol_crc; /* header crc */
609 u_int32_t vol_flags; /* volume flags */
610 u_int32_t vol_rootvol; /* which volume is the root volume? */
612 int32_t vol_reserved04;
613 int32_t vol_reserved05;
614 u_int32_t vol_reserved06;
615 u_int32_t vol_reserved07;
617 int32_t vol_blocksize; /* for statfs only */
618 int32_t vol_reserved08;
619 int64_t vol_nblocks; /* total allocatable hammer bufs */
622 * These fields are initialized and space is reserved in every
623 * volume making up a HAMMER filesytem, but only the master volume
624 * contains valid data. Note that vol0_stat_bigblocks does not
625 * include big-blocks for freemap and undomap initially allocated
628 int64_t vol0_stat_bigblocks; /* total big-blocks when fs is empty */
629 int64_t vol0_stat_freebigblocks;/* number of free big-blocks */
630 int64_t vol0_stat_bytes; /* for statfs only */
631 int64_t vol0_stat_inodes; /* for statfs only */
632 int64_t vol0_stat_records; /* total records in filesystem */
633 hammer_off_t vol0_btree_root; /* B-Tree root */
634 hammer_tid_t vol0_next_tid; /* highest partially synchronized TID */
635 hammer_off_t vol0_unused03;
638 * Blockmaps for zones. Not all zones use a blockmap. Note that
639 * the entire root blockmap is cached in the hammer_mount structure.
641 struct hammer_blockmap vol0_blockmap[HAMMER_MAX_ZONES];
644 * Array of zone-2 addresses for undo FIFO.
646 hammer_off_t vol0_undo_array[HAMMER_UNDO_LAYER2];
649 typedef struct hammer_volume_ondisk *hammer_volume_ondisk_t;
651 #define HAMMER_VOLF_VALID 0x0001 /* valid entry */
652 #define HAMMER_VOLF_OPEN 0x0002 /* volume is open */
653 #define HAMMER_VOLF_NEEDFLUSH 0x0004 /* volume needs flush */
655 #define HAMMER_VOL_CRCSIZE1 \
656 offsetof(struct hammer_volume_ondisk, vol_crc)
657 #define HAMMER_VOL_CRCSIZE2 \
658 (sizeof(struct hammer_volume_ondisk) - HAMMER_VOL_CRCSIZE1 - \
659 sizeof(hammer_crc_t))
661 #define HAMMER_VOL_VERSION_MIN 1 /* minimum supported version */
662 #define HAMMER_VOL_VERSION_DEFAULT 6 /* newfs default version */
663 #define HAMMER_VOL_VERSION_WIP 7 /* version >= this is WIP */
664 #define HAMMER_VOL_VERSION_MAX 6 /* maximum supported version */
666 #define HAMMER_VOL_VERSION_ONE 1
667 #define HAMMER_VOL_VERSION_TWO 2 /* new dirent layout (2.3+) */
668 #define HAMMER_VOL_VERSION_THREE 3 /* new snapshot layout (2.5+) */
669 #define HAMMER_VOL_VERSION_FOUR 4 /* new undo/flush (2.5+) */
670 #define HAMMER_VOL_VERSION_FIVE 5 /* dedup (2.9+) */
671 #define HAMMER_VOL_VERSION_SIX 6 /* DIRHASH_ALG1 */
674 * Record types are fairly straightforward. The B-Tree includes the record
675 * type in its index sort.
677 #define HAMMER_RECTYPE_UNKNOWN 0
678 #define HAMMER_RECTYPE_LOWEST 1 /* lowest record type avail */
679 #define HAMMER_RECTYPE_INODE 1 /* inode in obj_id space */
680 #define HAMMER_RECTYPE_UNUSED02 2
681 #define HAMMER_RECTYPE_UNUSED03 3
682 #define HAMMER_RECTYPE_DATA 0x0010
683 #define HAMMER_RECTYPE_DIRENTRY 0x0011
684 #define HAMMER_RECTYPE_DB 0x0012
685 #define HAMMER_RECTYPE_EXT 0x0013 /* ext attributes */
686 #define HAMMER_RECTYPE_FIX 0x0014 /* fixed attribute */
687 #define HAMMER_RECTYPE_PFS 0x0015 /* PFS management */
688 #define HAMMER_RECTYPE_SNAPSHOT 0x0016 /* Snapshot management */
689 #define HAMMER_RECTYPE_CONFIG 0x0017 /* hammer cleanup config */
690 #define HAMMER_RECTYPE_MAX 0xFFFF
692 #define HAMMER_RECTYPE_ENTRY_START (HAMMER_RECTYPE_INODE + 1)
693 #define HAMMER_RECTYPE_CLEAN_START HAMMER_RECTYPE_EXT
695 #define HAMMER_FIXKEY_SYMLINK 1
697 #define HAMMER_OBJTYPE_UNKNOWN 0 /* never exists on-disk as unknown */
698 #define HAMMER_OBJTYPE_DIRECTORY 1
699 #define HAMMER_OBJTYPE_REGFILE 2
700 #define HAMMER_OBJTYPE_DBFILE 3
701 #define HAMMER_OBJTYPE_FIFO 4
702 #define HAMMER_OBJTYPE_CDEV 5
703 #define HAMMER_OBJTYPE_BDEV 6
704 #define HAMMER_OBJTYPE_SOFTLINK 7
705 #define HAMMER_OBJTYPE_PSEUDOFS 8 /* pseudo filesystem obj */
706 #define HAMMER_OBJTYPE_SOCKET 9
709 * HAMMER inode attribute data
711 * The data reference for a HAMMER inode points to this structure. Any
712 * modifications to the contents of this structure will result in a
713 * replacement operation.
715 * parent_obj_id is only valid for directories (which cannot be hard-linked),
716 * and specifies the parent directory obj_id. This field will also be set
717 * for non-directory inodes as a recovery aid, but can wind up holding
718 * stale information. However, since object id's are not reused, the worse
719 * that happens is that the recovery code is unable to use it.
721 * NOTE: Future note on directory hardlinks. We can implement a record type
722 * which allows us to point to multiple parent directories.
724 struct hammer_inode_data {
725 u_int16_t version; /* inode data version */
726 u_int16_t mode; /* basic unix permissions */
727 u_int32_t uflags; /* chflags */
728 u_int32_t rmajor; /* used by device nodes */
729 u_int32_t rminor; /* used by device nodes */
731 int64_t parent_obj_id; /* parent directory obj_id */
736 u_int8_t cap_flags; /* capability support flags (extension) */
737 u_int16_t reserved02;
738 u_int32_t reserved03; /* RESERVED FOR POSSIBLE FUTURE BIRTHTIME */
739 u_int64_t nlinks; /* hard links */
740 u_int64_t size; /* filesystem object size */
744 u_int32_t parent_obj_localization;
745 u_int32_t integrity_crc;
747 char symlink[24]; /* HAMMER_INODE_BASESYMLEN */
749 u_int64_t mtime; /* mtime must be second-to-last */
750 u_int64_t atime; /* atime must be last */
754 * Neither mtime nor atime upates are CRCd by the B-Tree element.
755 * mtime updates have UNDO, atime updates do not.
757 #define HAMMER_ITIMES_BASE(ino_data) (&(ino_data)->mtime)
758 #define HAMMER_ITIMES_BYTES (sizeof(u_int64_t) * 2)
760 #define HAMMER_INODE_CRCSIZE \
761 offsetof(struct hammer_inode_data, mtime)
763 #define HAMMER_INODE_DATA_VERSION 1
764 #define HAMMER_OBJID_ROOT 1 /* root inodes # */
765 #define HAMMER_INODE_BASESYMLEN 24 /* see ext.symlink */
768 * Capability & implementation flags.
770 * HAMMER_INODE_CAP_DIR_LOCAL_INO - Use inode B-Tree localization
771 * for directory entries. Also see HAMMER_DIR_INODE_LOCALIZATION().
773 #define HAMMER_INODE_CAP_DIRHASH_MASK 0x03 /* directory: hash algorithm */
774 #define HAMMER_INODE_CAP_DIRHASH_ALG0 0x00
775 #define HAMMER_INODE_CAP_DIRHASH_ALG1 0x01
776 #define HAMMER_INODE_CAP_DIRHASH_ALG2 0x02
777 #define HAMMER_INODE_CAP_DIRHASH_ALG3 0x03
778 #define HAMMER_INODE_CAP_DIR_LOCAL_INO 0x04 /* use inode localization */
781 * A HAMMER directory entry associates a HAMMER filesystem object with a
782 * namespace. It is possible to hook into a pseudo-filesystem (with its
783 * own inode numbering space) in the filesystem by setting the high
784 * 16 bits of the localization field. The low 16 bits must be 0 and
785 * are reserved for future use.
787 * Directory entries are indexed with a 128 bit namekey rather then an
788 * offset. A portion of the namekey is an iterator/randomizer to deal
791 * NOTE: leaf.base.obj_type from the related B-Tree leaf entry holds
792 * the filesystem object type of obj_id, e.g. a den_type equivalent.
793 * It is not stored in hammer_entry_data.
795 * NOTE: name field / the filename data reference is NOT terminated with \0.
797 struct hammer_entry_data {
798 int64_t obj_id; /* object being referenced */
799 u_int32_t localization; /* identify pseudo-filesystem */
800 u_int32_t reserved02;
801 char name[16]; /* name (extended) */
804 #define HAMMER_ENTRY_NAME_OFF offsetof(struct hammer_entry_data, name[0])
805 #define HAMMER_ENTRY_SIZE(nlen) offsetof(struct hammer_entry_data, name[nlen])
808 * Symlink data which does not fit in the inode is stored in a separate
811 struct hammer_symlink_data {
812 char name[16]; /* name (extended) */
815 #define HAMMER_SYMLINK_NAME_OFF offsetof(struct hammer_symlink_data, name[0])
818 * The root inode for the primary filesystem and root inode for any
819 * pseudo-fs may be tagged with an optional data structure using
820 * HAMMER_RECTYPE_PFS and localization id. This structure allows
821 * the node to be used as a mirroring master or slave.
823 * When operating as a slave CD's into the node automatically become read-only
824 * and as-of sync_end_tid.
826 * When operating as a master the read PFSD info sets sync_end_tid to
827 * the most recently flushed TID.
829 * sync_low_tid is not yet used but will represent the highest pruning
830 * end-point, after which full history is available.
832 * We need to pack this structure making it equally sized on both 32-bit and
833 * 64-bit machines as it is part of struct hammer_ioc_mrecord_pfs which is
834 * send over the wire in hammer mirror operations. Only on 64-bit machines
835 * the size of this struct differ when packed or not. This leads us to the
836 * situation where old 64-bit systems (using the non-packed structure),
837 * which were never able to mirror to/from 32-bit systems, are now no longer
838 * able to mirror to/from newer 64-bit systems (using the packed structure).
840 struct hammer_pseudofs_data {
841 hammer_tid_t sync_low_tid; /* full history beyond this point */
842 hammer_tid_t sync_beg_tid; /* earliest tid w/ full history avail */
843 hammer_tid_t sync_end_tid; /* current synchronizatoin point */
844 u_int64_t sync_beg_ts; /* real-time of last completed sync */
845 u_int64_t sync_end_ts; /* initiation of current sync cycle */
846 uuid_t shared_uuid; /* shared uuid (match required) */
847 uuid_t unique_uuid; /* unique uuid of this master/slave */
848 int32_t reserved01; /* reserved for future master_id */
849 int32_t mirror_flags; /* misc flags */
850 char label[64]; /* filesystem space label */
851 char snapshots[64]; /* softlink dir for pruning */
852 int16_t prune_time; /* how long to spend pruning */
853 int16_t prune_freq; /* how often we prune */
854 int16_t reblock_time; /* how long to spend reblocking */
855 int16_t reblock_freq; /* how often we reblock */
856 int32_t snapshot_freq; /* how often we create a snapshot */
857 int32_t prune_min; /* do not prune recent history */
858 int32_t prune_max; /* do not retain history beyond here */
859 int32_t reserved[16];
862 typedef struct hammer_pseudofs_data *hammer_pseudofs_data_t;
864 #define HAMMER_PFSD_SLAVE 0x00000001
865 #define HAMMER_PFSD_DELETED 0x80000000
868 * Snapshot meta-data { Objid = HAMMER_OBJID_ROOT, Key = tid, rectype = SNAPSHOT }.
870 * Snapshot records replace the old <fs>/snapshots/<softlink> methodology. Snapshot
871 * records are mirrored but may be independantly managed once they are laid down on
874 * NOTE: The b-tree key is signed, the tid is not, so callers must still sort the
877 * NOTE: Reserved fields must be zero (as usual)
879 struct hammer_snapshot_data {
880 hammer_tid_t tid; /* the snapshot TID itself (== key) */
881 u_int64_t ts; /* real-time when snapshot was made */
882 u_int64_t reserved01;
883 u_int64_t reserved02;
884 char label[64]; /* user-supplied description */
885 u_int64_t reserved03[4];
889 * Config meta-data { ObjId = HAMMER_OBJID_ROOT, Key = 0, rectype = CONFIG }.
891 * Used to store the hammer cleanup config. This data is not mirrored.
893 struct hammer_config_data {
898 * Rollup various structures embedded as record data
900 union hammer_data_ondisk {
901 struct hammer_entry_data entry;
902 struct hammer_inode_data inode;
903 struct hammer_symlink_data symlink;
904 struct hammer_pseudofs_data pfsd;
905 struct hammer_snapshot_data snap;
906 struct hammer_config_data config;
909 typedef union hammer_data_ondisk *hammer_data_ondisk_t;
912 * Ondisk layout of B-Tree related structures
914 #include "hammer_btree.h"
916 #define HAMMER_DIR_INODE_LOCALIZATION(ino_data) \
917 (((ino_data)->cap_flags & HAMMER_INODE_CAP_DIR_LOCAL_INO) ? \
918 HAMMER_LOCALIZE_INODE : \
919 HAMMER_LOCALIZE_MISC)
921 #endif /* !VFS_HAMMER_DISK_H_ */