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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12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
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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.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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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. Most buffer-sized headers such as those
60 * used by volumes, super-clusters, clusters, and basic filesystem buffers
61 * use fixed-sized A-lists which are heavily dependant on HAMMER_BUFSIZE.
63 * 64K X-bufs are used for blocks >= a file's 1MB mark.
65 * Per-volume storage limit: 52 bits 4096 TB
66 * Per-Zone storage limit: 59 bits 512 KTB (due to blockmap)
67 * Per-filesystem storage limit: 60 bits 1 MTB
69 #define HAMMER_BUFSIZE 16384
70 #define HAMMER_XBUFSIZE 65536
71 #define HAMMER_XDEMARC (1024 * 1024)
72 #define HAMMER_BUFMASK (HAMMER_BUFSIZE - 1)
73 #define HAMMER_XBUFMASK (HAMMER_XBUFSIZE - 1)
74 #define HAMMER_BUFFER_BITS 14
76 #if (1 << HAMMER_BUFFER_BITS) != HAMMER_BUFSIZE
77 #error "HAMMER_BUFFER_BITS BROKEN"
80 #define HAMMER_BUFSIZE64 ((u_int64_t)HAMMER_BUFSIZE)
81 #define HAMMER_BUFMASK64 ((u_int64_t)HAMMER_BUFMASK)
83 #define HAMMER_XBUFSIZE64 ((u_int64_t)HAMMER_XBUFSIZE)
84 #define HAMMER_XBUFMASK64 ((u_int64_t)HAMMER_XBUFMASK)
86 #define HAMMER_OFF_ZONE_MASK 0xF000000000000000ULL /* zone portion */
87 #define HAMMER_OFF_VOL_MASK 0x0FF0000000000000ULL /* volume portion */
88 #define HAMMER_OFF_SHORT_MASK 0x000FFFFFFFFFFFFFULL /* offset portion */
89 #define HAMMER_OFF_LONG_MASK 0x0FFFFFFFFFFFFFFFULL /* offset portion */
90 #define HAMMER_OFF_SHORT_REC_MASK 0x000FFFFFFF000000ULL /* recovery boundary */
91 #define HAMMER_OFF_LONG_REC_MASK 0x0FFFFFFFFF000000ULL /* recovery boundary */
92 #define HAMMER_RECOVERY_BND 0x0000000001000000ULL
95 * The current limit of volumes that can make up a HAMMER FS
97 #define HAMMER_MAX_VOLUMES 256
100 * Hammer transction ids are 64 bit unsigned integers and are usually
101 * synchronized with the time of day in nanoseconds.
103 * Hammer offsets are used for FIFO indexing and embed a cycle counter
104 * and volume number in addition to the offset. Most offsets are required
105 * to be 64-byte aligned.
107 typedef u_int64_t hammer_tid_t;
108 typedef u_int64_t hammer_off_t;
109 typedef u_int32_t hammer_seq_t;
110 typedef u_int32_t hammer_crc_t;
112 #define HAMMER_MIN_TID 0ULL /* unsigned */
113 #define HAMMER_MAX_TID 0xFFFFFFFFFFFFFFFFULL /* unsigned */
114 #define HAMMER_MIN_KEY -0x8000000000000000LL /* signed */
115 #define HAMMER_MAX_KEY 0x7FFFFFFFFFFFFFFFLL /* signed */
116 #define HAMMER_MIN_OBJID HAMMER_MIN_KEY /* signed */
117 #define HAMMER_MAX_OBJID HAMMER_MAX_KEY /* signed */
118 #define HAMMER_MIN_RECTYPE 0x0U /* unsigned */
119 #define HAMMER_MAX_RECTYPE 0xFFFFU /* unsigned */
120 #define HAMMER_MIN_OFFSET 0ULL /* unsigned */
121 #define HAMMER_MAX_OFFSET 0xFFFFFFFFFFFFFFFFULL /* unsigned */
124 * hammer_off_t has several different encodings. Note that not all zones
127 * zone 0: reserved for sanity
128 * zone 1 (z,v,o): raw volume relative (offset 0 is the volume header)
129 * zone 2 (z,v,o): raw buffer relative (offset 0 is the first buffer)
130 * zone 3 (z,o): undo fifo - actually fixed phys array in vol hdr
131 * zone 4 (z,v,o): freemap - only real blockmap
132 * zone 8 (z,v,o): B-Tree - actually zone-2 address
133 * zone 9 (z,v,o): Record - actually zone-2 address
134 * zone 10 (z,v,o): Large-data - actually zone-2 address
135 * zone 15: reserved for sanity
137 * layer1/layer2 direct map:
138 * zzzzvvvvvvvvoooo oooooooooooooooo oooooooooooooooo oooooooooooooooo
139 * ----111111111111 1111112222222222 222222222ooooooo oooooooooooooooo
142 #define HAMMER_ZONE_RAW_VOLUME 0x1000000000000000ULL
143 #define HAMMER_ZONE_RAW_BUFFER 0x2000000000000000ULL
144 #define HAMMER_ZONE_UNDO 0x3000000000000000ULL
145 #define HAMMER_ZONE_FREEMAP 0x4000000000000000ULL
146 #define HAMMER_ZONE_RESERVED05 0x5000000000000000ULL
147 #define HAMMER_ZONE_RESERVED06 0x6000000000000000ULL
148 #define HAMMER_ZONE_RESERVED07 0x7000000000000000ULL
149 #define HAMMER_ZONE_BTREE 0x8000000000000000ULL
150 #define HAMMER_ZONE_META 0x9000000000000000ULL
151 #define HAMMER_ZONE_LARGE_DATA 0xA000000000000000ULL
152 #define HAMMER_ZONE_SMALL_DATA 0xB000000000000000ULL
153 #define HAMMER_ZONE_RESERVED0C 0xC000000000000000ULL
154 #define HAMMER_ZONE_RESERVED0D 0xD000000000000000ULL
155 #define HAMMER_ZONE_RESERVED0E 0xE000000000000000ULL
156 #define HAMMER_ZONE_UNAVAIL 0xF000000000000000ULL
158 #define HAMMER_ZONE_RAW_VOLUME_INDEX 1
159 #define HAMMER_ZONE_RAW_BUFFER_INDEX 2
160 #define HAMMER_ZONE_UNDO_INDEX 3
161 #define HAMMER_ZONE_FREEMAP_INDEX 4
162 #define HAMMER_ZONE_BTREE_INDEX 8
163 #define HAMMER_ZONE_META_INDEX 9
164 #define HAMMER_ZONE_LARGE_DATA_INDEX 10
165 #define HAMMER_ZONE_SMALL_DATA_INDEX 11
166 #define HAMMER_ZONE_UNAVAIL_INDEX 15 /* unavailable */
168 #define HAMMER_MAX_ZONES 16
170 #define HAMMER_VOL_ENCODE(vol_no) \
171 ((hammer_off_t)((vol_no) & 255) << 52)
172 #define HAMMER_VOL_DECODE(ham_off) \
173 (int32_t)(((hammer_off_t)(ham_off) >> 52) & 255)
174 #define HAMMER_ZONE_DECODE(ham_off) \
175 (int32_t)(((hammer_off_t)(ham_off) >> 60))
176 #define HAMMER_ZONE_ENCODE(zone, ham_off) \
177 (((hammer_off_t)(zone) << 60) | (ham_off))
178 #define HAMMER_SHORT_OFF_ENCODE(offset) \
179 ((hammer_off_t)(offset) & HAMMER_OFF_SHORT_MASK)
180 #define HAMMER_LONG_OFF_ENCODE(offset) \
181 ((hammer_off_t)(offset) & HAMMER_OFF_LONG_MASK)
183 #define HAMMER_ENCODE_RAW_VOLUME(vol_no, offset) \
184 (HAMMER_ZONE_RAW_VOLUME | \
185 HAMMER_VOL_ENCODE(vol_no) | \
186 HAMMER_SHORT_OFF_ENCODE(offset))
188 #define HAMMER_ENCODE_RAW_BUFFER(vol_no, offset) \
189 (HAMMER_ZONE_RAW_BUFFER | \
190 HAMMER_VOL_ENCODE(vol_no) | \
191 HAMMER_SHORT_OFF_ENCODE(offset))
193 #define HAMMER_ENCODE_FREEMAP(vol_no, offset) \
194 (HAMMER_ZONE_FREEMAP | \
195 HAMMER_VOL_ENCODE(vol_no) | \
196 HAMMER_SHORT_OFF_ENCODE(offset))
199 * Large-Block backing store
201 * A blockmap is a two-level map which translates a blockmap-backed zone
202 * offset into a raw zone 2 offset. Each layer handles 18 bits. The 8M
203 * large-block size is 23 bits so two layers gives us 23+18+18 = 59 bits
206 * When using hinting for a blockmap lookup, the hint is lost when the
207 * scan leaves the HINTBLOCK, which is typically several LARGEBLOCK's.
208 * HINTBLOCK is a heuristic.
210 #define HAMMER_HINTBLOCK_SIZE (HAMMER_LARGEBLOCK_SIZE * 4)
211 #define HAMMER_HINTBLOCK_MASK64 ((u_int64_t)HAMMER_HINTBLOCK_SIZE - 1)
212 #define HAMMER_LARGEBLOCK_SIZE (8192 * 1024)
213 #define HAMMER_LARGEBLOCK_OVERFILL (6144 * 1024)
214 #define HAMMER_LARGEBLOCK_SIZE64 ((u_int64_t)HAMMER_LARGEBLOCK_SIZE)
215 #define HAMMER_LARGEBLOCK_MASK (HAMMER_LARGEBLOCK_SIZE - 1)
216 #define HAMMER_LARGEBLOCK_MASK64 ((u_int64_t)HAMMER_LARGEBLOCK_SIZE - 1)
217 #define HAMMER_LARGEBLOCK_BITS 23
218 #if (1 << HAMMER_LARGEBLOCK_BITS) != HAMMER_LARGEBLOCK_SIZE
219 #error "HAMMER_LARGEBLOCK_BITS BROKEN"
222 #define HAMMER_BUFFERS_PER_LARGEBLOCK \
223 (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE)
224 #define HAMMER_BUFFERS_PER_LARGEBLOCK_MASK \
225 (HAMMER_BUFFERS_PER_LARGEBLOCK - 1)
226 #define HAMMER_BUFFERS_PER_LARGEBLOCK_MASK64 \
227 ((hammer_off_t)HAMMER_BUFFERS_PER_LARGEBLOCK_MASK)
230 * Maximum number of mirrors operating in master mode (multi-master
231 * clustering and mirroring).
233 #define HAMMER_MAX_MASTERS 16
236 * The blockmap is somewhat of a degenerate structure. HAMMER only actually
237 * uses it in its original incarnation to implement the free-map.
239 * zone:1 raw volume (no blockmap)
240 * zone:2 raw buffer (no blockmap)
241 * zone:3 undo-map (direct layer2 array in volume header)
242 * zone:4 free-map (the only real blockmap)
243 * zone:8-15 zone id used to classify big-block only, address is actually
246 struct hammer_blockmap {
247 hammer_off_t phys_offset; /* zone-2 physical offset */
248 hammer_off_t first_offset; /* zone-X logical offset (zone 3) */
249 hammer_off_t next_offset; /* zone-X logical offset */
250 hammer_off_t alloc_offset; /* zone-X logical offset */
251 u_int32_t reserved01;
252 hammer_crc_t entry_crc;
255 typedef struct hammer_blockmap *hammer_blockmap_t;
257 #define HAMMER_BLOCKMAP_CRCSIZE \
258 offsetof(struct hammer_blockmap, entry_crc)
261 * The blockmap is a 2-layer entity made up of big-blocks. The first layer
262 * contains 262144 32-byte entries (18 bits), the second layer contains
263 * 524288 16-byte entries (19 bits), representing 8MB (23 bit) blockmaps.
264 * 18+19+23 = 60 bits. The top four bits are the zone id.
266 * Currently only the freemap utilizes both layers in all their glory.
267 * All primary data/meta-data zones actually encode a zone-2 address
268 * requiring no real blockmap translation.
270 * The freemap uses the upper 8 bits of layer-1 to identify the volume,
271 * thus any space allocated via the freemap can be directly translated
272 * to a zone:2 (or zone:8-15) address.
274 * zone-X blockmap offset: [z:4][layer1:18][layer2:19][bigblock:23]
276 struct hammer_blockmap_layer1 {
277 hammer_off_t blocks_free; /* big-blocks free */
278 hammer_off_t phys_offset; /* UNAVAIL or zone-2 */
279 hammer_off_t reserved01;
280 hammer_crc_t layer2_crc; /* xor'd crc's of HAMMER_BLOCKSIZE */
282 hammer_crc_t layer1_crc; /* MUST BE LAST FIELD OF STRUCTURE*/
285 typedef struct hammer_blockmap_layer1 *hammer_blockmap_layer1_t;
287 #define HAMMER_LAYER1_CRCSIZE \
288 offsetof(struct hammer_blockmap_layer1, layer1_crc)
290 struct hammer_blockmap_layer2 {
291 u_int8_t zone; /* typed allocation zone */
294 u_int32_t append_off; /* allocatable space index */
295 u_int32_t bytes_free; /* bytes free within this bigblock */
296 hammer_crc_t entry_crc;
299 typedef struct hammer_blockmap_layer2 *hammer_blockmap_layer2_t;
301 #define HAMMER_LAYER2_CRCSIZE \
302 offsetof(struct hammer_blockmap_layer2, entry_crc)
304 #define HAMMER_BLOCKMAP_FREE 0ULL
305 #define HAMMER_BLOCKMAP_UNAVAIL ((hammer_off_t)-1LL)
307 #define HAMMER_BLOCKMAP_RADIX1 /* 262144 (18) */ \
308 (HAMMER_LARGEBLOCK_SIZE / sizeof(struct hammer_blockmap_layer1))
309 #define HAMMER_BLOCKMAP_RADIX2 /* 524288 (19) */ \
310 (HAMMER_LARGEBLOCK_SIZE / sizeof(struct hammer_blockmap_layer2))
312 #define HAMMER_BLOCKMAP_RADIX1_PERBUFFER \
313 (HAMMER_BLOCKMAP_RADIX1 / (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE))
314 #define HAMMER_BLOCKMAP_RADIX2_PERBUFFER \
315 (HAMMER_BLOCKMAP_RADIX2 / (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE))
317 #define HAMMER_BLOCKMAP_LAYER1 /* 18+19+23 */ \
318 (HAMMER_BLOCKMAP_RADIX1 * HAMMER_BLOCKMAP_LAYER2)
319 #define HAMMER_BLOCKMAP_LAYER2 /* 19+23 - 4TB */ \
320 (HAMMER_BLOCKMAP_RADIX2 * HAMMER_LARGEBLOCK_SIZE64)
322 #define HAMMER_BLOCKMAP_LAYER1_MASK (HAMMER_BLOCKMAP_LAYER1 - 1)
323 #define HAMMER_BLOCKMAP_LAYER2_MASK (HAMMER_BLOCKMAP_LAYER2 - 1)
326 * byte offset within layer1 or layer2 big-block for the entry representing
327 * a zone-2 physical offset.
329 #define HAMMER_BLOCKMAP_LAYER1_OFFSET(zone2_offset) \
330 (((zone2_offset) & HAMMER_BLOCKMAP_LAYER1_MASK) / \
331 HAMMER_BLOCKMAP_LAYER2 * sizeof(struct hammer_blockmap_layer1))
333 #define HAMMER_BLOCKMAP_LAYER2_OFFSET(zone2_offset) \
334 (((zone2_offset) & HAMMER_BLOCKMAP_LAYER2_MASK) / \
335 HAMMER_LARGEBLOCK_SIZE64 * sizeof(struct hammer_blockmap_layer2))
338 * HAMMER UNDO parameters. The UNDO fifo is mapped directly in the volume
339 * header with an array of layer2 structures. A maximum of (128x8MB) = 1GB
340 * may be reserved. The size of the undo fifo is usually set a newfs time
341 * but can be adjusted if the filesystem is taken offline.
343 #define HAMMER_UNDO_LAYER2 128 /* max layer2 undo mapping entries */
346 * All on-disk HAMMER structures which make up elements of the UNDO FIFO
347 * contain a hammer_fifo_head and hammer_fifo_tail structure. This structure
348 * contains all the information required to validate the fifo element
349 * and to scan the fifo in either direction. The head is typically embedded
350 * in higher level hammer on-disk structures while the tail is typically
351 * out-of-band. hdr_size is the size of the whole mess, including the tail.
353 * All undo structures are guaranteed to not cross a 16K filesystem
354 * buffer boundary. Most undo structures are fairly small. Data spaces
355 * are not immediately reused by HAMMER so file data is not usually recorded
356 * as part of an UNDO.
358 * PAD elements are allowed to take up only 8 bytes of space as a special
359 * case, containing only hdr_signature, hdr_type, and hdr_size fields,
360 * and with the tail overloaded onto the head structure for 8 bytes total.
362 * Every undo record has a sequence number. This number is unrelated to
363 * transaction ids and instead collects the undo transactions associated
364 * with a single atomic operation. A larger transactional operation, such
365 * as a remove(), may consist of several smaller atomic operations
366 * representing raw meta-data operations.
368 * HAMMER VERSION 4 CHANGES
370 * In HAMMER version 4 the undo structure alignment is reduced from 16384
371 * to 512 bytes in order to ensure that each 512 byte sector begins with
372 * a header. The reserved01 field in the header is now a 32 bit sequence
373 * number. This allows the recovery code to detect missing sectors
374 * without relying on the 32-bit crc and to definitively identify the current
375 * undo sequence space without having to rely on information from the volume
376 * header. In addition, new REDO entries in the undo space are used to
377 * record write, write/extend, and transaction id updates.
379 * The grand result is:
381 * (1) The volume header no longer needs to be synchronized for most
382 * flush and fsync operations.
384 * (2) Most fsync operations need only lay down REDO records
386 * (3) Data overwrite for nohistory operations covered by REDO records
387 * can be supported (instead of rolling a new block allocation),
388 * by rolling UNDO for the prior contents of the data.
390 #define HAMMER_HEAD_ONDISK_SIZE 32
391 #define HAMMER_HEAD_ALIGN 8
392 #define HAMMER_HEAD_ALIGN_MASK (HAMMER_HEAD_ALIGN - 1)
393 #define HAMMER_TAIL_ONDISK_SIZE 8
394 #define HAMMER_HEAD_DOALIGN(bytes) \
395 (((bytes) + HAMMER_HEAD_ALIGN_MASK) & ~HAMMER_HEAD_ALIGN_MASK)
397 #define HAMMER_UNDO_ALIGN 512
398 #define HAMMER_UNDO_ALIGN64 ((u_int64_t)512)
399 #define HAMMER_UNDO_MASK (HAMMER_UNDO_ALIGN - 1)
400 #define HAMMER_UNDO_MASK64 (HAMMER_UNDO_ALIGN64 - 1)
402 struct hammer_fifo_head {
403 u_int16_t hdr_signature;
405 u_int32_t hdr_size; /* Aligned size of the whole mess */
406 u_int32_t hdr_seq; /* Sequence number */
407 hammer_crc_t hdr_crc; /* XOR crc up to field w/ crc after field */
410 #define HAMMER_FIFO_HEAD_CRCOFF offsetof(struct hammer_fifo_head, hdr_crc)
412 struct hammer_fifo_tail {
413 u_int16_t tail_signature;
415 u_int32_t tail_size; /* aligned size of the whole mess */
418 typedef struct hammer_fifo_head *hammer_fifo_head_t;
419 typedef struct hammer_fifo_tail *hammer_fifo_tail_t;
424 #define HAMMER_HEAD_TYPE_PAD (0x0040U|HAMMER_HEAD_FLAG_FREE)
425 #define HAMMER_HEAD_TYPE_DUMMY 0x0041U /* dummy entry w/seqno */
426 #define HAMMER_HEAD_TYPE_42 0x0042U
427 #define HAMMER_HEAD_TYPE_UNDO 0x0043U /* random UNDO information */
428 #define HAMMER_HEAD_TYPE_REDO 0x0044U /* data REDO / fast fsync */
429 #define HAMMER_HEAD_TYPE_45 0x0045U
431 #define HAMMER_HEAD_FLAG_FREE 0x8000U /* Indicates object freed */
433 #define HAMMER_HEAD_SIGNATURE 0xC84EU
434 #define HAMMER_TAIL_SIGNATURE 0xC74FU
436 #define HAMMER_HEAD_SEQ_BEG 0x80000000U
437 #define HAMMER_HEAD_SEQ_END 0x40000000U
438 #define HAMMER_HEAD_SEQ_MASK 0x3FFFFFFFU
441 * Misc FIFO structures.
443 * NOTE: redo records are for version 4+ filesystems.
445 struct hammer_fifo_undo {
446 struct hammer_fifo_head head;
447 hammer_off_t undo_offset; /* zone-1 offset */
448 int32_t undo_data_bytes;
449 int32_t undo_reserved01;
450 /* followed by data */
453 struct hammer_fifo_redo {
454 struct hammer_fifo_head head;
455 int64_t redo_objid; /* file being written */
456 hammer_off_t redo_offset; /* logical offset in file */
457 int32_t redo_data_bytes;
458 int32_t redo_reserved01;
461 union hammer_fifo_any {
462 struct hammer_fifo_head head;
463 struct hammer_fifo_undo undo;
464 struct hammer_fifo_redo redo;
467 typedef struct hammer_fifo_redo *hammer_fifo_redo_t;
468 typedef struct hammer_fifo_undo *hammer_fifo_undo_t;
469 typedef union hammer_fifo_any *hammer_fifo_any_t;
472 * Volume header types
474 #define HAMMER_FSBUF_VOLUME 0xC8414D4DC5523031ULL /* HAMMER01 */
475 #define HAMMER_FSBUF_VOLUME_REV 0x313052C54D4D41C8ULL /* (reverse endian) */
478 * The B-Tree structures need hammer_fsbuf_head.
480 #include "hammer_btree.h"
483 * HAMMER Volume header
485 * A HAMMER filesystem is built from any number of block devices, Each block
486 * device contains a volume header followed by however many buffers fit
489 * One of the volumes making up a HAMMER filesystem is the master, the
490 * rest are slaves. It does not have to be volume #0.
492 * The volume header takes up an entire 16K filesystem buffer and may
493 * represent up to 64KTB (65536 TB) of space.
495 * Special field notes:
497 * vol_bot_beg - offset of boot area (mem_beg - bot_beg bytes)
498 * vol_mem_beg - offset of memory log (clu_beg - mem_beg bytes)
499 * vol_buf_beg - offset of the first buffer.
501 * The memory log area allows a kernel to cache new records and data
502 * in memory without allocating space in the actual filesystem to hold
503 * the records and data. In the event that a filesystem becomes full,
504 * any records remaining in memory can be flushed to the memory log
505 * area. This allows the kernel to immediately return success.
508 #define HAMMER_BOOT_MINBYTES (32*1024)
509 #define HAMMER_BOOT_NOMBYTES (64LL*1024*1024)
510 #define HAMMER_BOOT_MAXBYTES (256LL*1024*1024)
512 #define HAMMER_MEM_MINBYTES (256*1024)
513 #define HAMMER_MEM_NOMBYTES (1LL*1024*1024*1024)
514 #define HAMMER_MEM_MAXBYTES (64LL*1024*1024*1024)
516 struct hammer_volume_ondisk {
517 u_int64_t vol_signature;/* Signature */
519 int64_t vol_bot_beg; /* byte offset of boot area or 0 */
520 int64_t vol_mem_beg; /* byte offset of memory log or 0 */
521 int64_t vol_buf_beg; /* byte offset of first buffer in volume */
522 int64_t vol_buf_end; /* byte offset of volume EOF (on buf bndry) */
523 int64_t vol_locked; /* reserved clusters are >= this offset */
525 uuid_t vol_fsid; /* identify filesystem */
526 uuid_t vol_fstype; /* identify filesystem type */
527 char vol_name[64]; /* Name of volume */
529 int32_t vol_no; /* volume number within filesystem */
530 int32_t vol_count; /* number of volumes making up FS */
532 u_int32_t vol_version; /* version control information */
533 hammer_crc_t vol_crc; /* header crc */
534 u_int32_t vol_flags; /* volume flags */
535 u_int32_t vol_rootvol; /* which volume is the root volume? */
537 int32_t vol_reserved04;
538 int32_t vol_reserved05;
539 u_int32_t vol_reserved06;
540 u_int32_t vol_reserved07;
542 int32_t vol_blocksize; /* for statfs only */
543 int32_t vol_reserved08;
544 int64_t vol_nblocks; /* total allocatable hammer bufs */
547 * These fields are initialized and space is reserved in every
548 * volume making up a HAMMER filesytem, but only the master volume
549 * contains valid data.
551 int64_t vol0_stat_bigblocks; /* total bigblocks when fs is empty */
552 int64_t vol0_stat_freebigblocks;/* number of free bigblocks */
553 int64_t vol0_stat_bytes; /* for statfs only */
554 int64_t vol0_stat_inodes; /* for statfs only */
555 int64_t vol0_stat_records; /* total records in filesystem */
556 hammer_off_t vol0_btree_root; /* B-Tree root */
557 hammer_tid_t vol0_next_tid; /* highest partially synchronized TID */
558 hammer_off_t vol0_unused03;
561 * Blockmaps for zones. Not all zones use a blockmap. Note that
562 * the entire root blockmap is cached in the hammer_mount structure.
564 struct hammer_blockmap vol0_blockmap[HAMMER_MAX_ZONES];
567 * Array of zone-2 addresses for undo FIFO.
569 hammer_off_t vol0_undo_array[HAMMER_UNDO_LAYER2];
573 typedef struct hammer_volume_ondisk *hammer_volume_ondisk_t;
575 #define HAMMER_VOLF_VALID 0x0001 /* valid entry */
576 #define HAMMER_VOLF_OPEN 0x0002 /* volume is open */
577 #define HAMMER_VOLF_NEEDFLUSH 0x0004 /* volume needs flush */
579 #define HAMMER_VOL_CRCSIZE1 \
580 offsetof(struct hammer_volume_ondisk, vol_crc)
581 #define HAMMER_VOL_CRCSIZE2 \
582 (sizeof(struct hammer_volume_ondisk) - HAMMER_VOL_CRCSIZE1 - \
583 sizeof(hammer_crc_t))
585 #define HAMMER_VOL_VERSION_MIN 1 /* minimum supported version */
586 #define HAMMER_VOL_VERSION_DEFAULT 4 /* newfs default version */
587 #define HAMMER_VOL_VERSION_WIP 5 /* version >= this is WIP */
588 #define HAMMER_VOL_VERSION_MAX 4 /* maximum supported version */
590 #define HAMMER_VOL_VERSION_ONE 1
591 #define HAMMER_VOL_VERSION_TWO 2 /* new dirent layout (2.3+) */
592 #define HAMMER_VOL_VERSION_THREE 3 /* new snapshot layout (2.5+) */
593 #define HAMMER_VOL_VERSION_FOUR 4 /* new undo/flush (2.5+) */
596 * Record types are fairly straightforward. The B-Tree includes the record
597 * type in its index sort.
599 #define HAMMER_RECTYPE_UNKNOWN 0
600 #define HAMMER_RECTYPE_LOWEST 1 /* lowest record type avail */
601 #define HAMMER_RECTYPE_INODE 1 /* inode in obj_id space */
602 #define HAMMER_RECTYPE_UNUSED02 2
603 #define HAMMER_RECTYPE_UNUSED03 3
604 #define HAMMER_RECTYPE_DATA 0x0010
605 #define HAMMER_RECTYPE_DIRENTRY 0x0011
606 #define HAMMER_RECTYPE_DB 0x0012
607 #define HAMMER_RECTYPE_EXT 0x0013 /* ext attributes */
608 #define HAMMER_RECTYPE_FIX 0x0014 /* fixed attribute */
609 #define HAMMER_RECTYPE_PFS 0x0015 /* PFS management */
610 #define HAMMER_RECTYPE_SNAPSHOT 0x0016 /* Snapshot management */
611 #define HAMMER_RECTYPE_CONFIG 0x0017 /* hammer cleanup config */
612 #define HAMMER_RECTYPE_MOVED 0x8000 /* special recovery flag */
613 #define HAMMER_RECTYPE_MAX 0xFFFF
615 #define HAMMER_RECTYPE_CLEAN_START HAMMER_RECTYPE_EXT
617 #define HAMMER_FIXKEY_SYMLINK 1
619 #define HAMMER_OBJTYPE_UNKNOWN 0 /* (never exists on-disk) */
620 #define HAMMER_OBJTYPE_DIRECTORY 1
621 #define HAMMER_OBJTYPE_REGFILE 2
622 #define HAMMER_OBJTYPE_DBFILE 3
623 #define HAMMER_OBJTYPE_FIFO 4
624 #define HAMMER_OBJTYPE_CDEV 5
625 #define HAMMER_OBJTYPE_BDEV 6
626 #define HAMMER_OBJTYPE_SOFTLINK 7
627 #define HAMMER_OBJTYPE_PSEUDOFS 8 /* pseudo filesystem obj */
628 #define HAMMER_OBJTYPE_SOCKET 9
631 * HAMMER inode attribute data
633 * The data reference for a HAMMER inode points to this structure. Any
634 * modifications to the contents of this structure will result in a
635 * replacement operation.
637 * parent_obj_id is only valid for directories (which cannot be hard-linked),
638 * and specifies the parent directory obj_id. This field will also be set
639 * for non-directory inodes as a recovery aid, but can wind up holding
640 * stale information. However, since object id's are not reused, the worse
641 * that happens is that the recovery code is unable to use it.
643 * NOTE: Future note on directory hardlinks. We can implement a record type
644 * which allows us to point to multiple parent directories.
646 * NOTE: atime is stored in the inode's B-Tree element and not in the inode
647 * data. This allows the atime to be updated without having to lay down a
650 struct hammer_inode_data {
651 u_int16_t version; /* inode data version */
652 u_int16_t mode; /* basic unix permissions */
653 u_int32_t uflags; /* chflags */
654 u_int32_t rmajor; /* used by device nodes */
655 u_int32_t rminor; /* used by device nodes */
657 int64_t parent_obj_id; /* parent directory obj_id */
662 u_int8_t cap_flags; /* capability support flags (extension) */
663 u_int16_t reserved02;
664 u_int32_t reserved03; /* RESERVED FOR POSSIBLE FUTURE BIRTHTIME */
665 u_int64_t nlinks; /* hard links */
666 u_int64_t size; /* filesystem object size */
670 u_int32_t parent_obj_localization;
671 u_int32_t integrity_crc;
673 char symlink[24]; /* HAMMER_INODE_BASESYMLEN */
675 u_int64_t mtime; /* mtime must be second-to-last */
676 u_int64_t atime; /* atime must be last */
680 * Neither mtime nor atime upates are CRCd by the B-Tree element.
681 * mtime updates have UNDO, atime updates do not.
683 #define HAMMER_ITIMES_BASE(ino_data) (&(ino_data)->mtime)
684 #define HAMMER_ITIMES_BYTES (sizeof(u_int64_t) * 2)
686 #define HAMMER_INODE_CRCSIZE \
687 offsetof(struct hammer_inode_data, mtime)
689 #define HAMMER_INODE_DATA_VERSION 1
690 #define HAMMER_OBJID_ROOT 1
691 #define HAMMER_INODE_BASESYMLEN 24 /* see ext.symlink */
694 * Capability & implementation flags.
696 * DIR_LOCAL_INO - Use inode B-Tree localization for directory entries.
698 #define HAMMER_INODE_CAP_DIRHASH_MASK 0x03 /* directory: hash algorithm */
699 #define HAMMER_INODE_CAP_DIRHASH_ALG0 0x00
700 #define HAMMER_INODE_CAP_DIRHASH_ALG1 0x01
701 #define HAMMER_INODE_CAP_DIRHASH_ALG2 0x02
702 #define HAMMER_INODE_CAP_DIRHASH_ALG3 0x03
703 #define HAMMER_INODE_CAP_DIR_LOCAL_INO 0x04 /* use inode localization */
706 * A HAMMER directory entry associates a HAMMER filesystem object with a
707 * namespace. It is possible to hook into a pseudo-filesystem (with its
708 * own inode numbering space) in the filesystem by setting the high
709 * 16 bits of the localization field. The low 16 bits must be 0 and
710 * are reserved for future use.
712 * Directory entries are indexed with a 128 bit namekey rather then an
713 * offset. A portion of the namekey is an iterator/randomizer to deal
716 * NOTE: base.base.obj_type from the related B-Tree leaf entry holds
717 * the filesystem object type of obj_id, e.g. a den_type equivalent.
718 * It is not stored in hammer_entry_data.
720 * NOTE: den_name / the filename data reference is NOT terminated with \0.
722 struct hammer_entry_data {
723 int64_t obj_id; /* object being referenced */
724 u_int32_t localization; /* identify pseudo-filesystem */
725 u_int32_t reserved02;
726 char name[16]; /* name (extended) */
729 #define HAMMER_ENTRY_NAME_OFF offsetof(struct hammer_entry_data, name[0])
730 #define HAMMER_ENTRY_SIZE(nlen) offsetof(struct hammer_entry_data, name[nlen])
733 * Symlink data which does not fit in the inode is stored in a separte
736 struct hammer_symlink_data {
740 #define HAMMER_SYMLINK_NAME_OFF offsetof(struct hammer_symlink_data, name[0])
743 * The root inode for the primary filesystem and root inode for any
744 * pseudo-fs may be tagged with an optional data structure using
745 * HAMMER_RECTYPE_FIX/HAMMER_FIXKEY_PSEUDOFS. This structure allows
746 * the node to be used as a mirroring master or slave.
748 * When operating as a slave CD's into the node automatically become read-only
749 * and as-of sync_end_tid.
751 * When operating as a master the read PFSD info sets sync_end_tid to
752 * the most recently flushed TID.
754 * sync_low_tid is not yet used but will represent the highest pruning
755 * end-point, after which full history is available.
757 struct hammer_pseudofs_data {
758 hammer_tid_t sync_low_tid; /* full history beyond this point */
759 hammer_tid_t sync_beg_tid; /* earliest tid w/ full history avail */
760 hammer_tid_t sync_end_tid; /* current synchronizatoin point */
761 u_int64_t sync_beg_ts; /* real-time of last completed sync */
762 u_int64_t sync_end_ts; /* initiation of current sync cycle */
763 uuid_t shared_uuid; /* shared uuid (match required) */
764 uuid_t unique_uuid; /* unique uuid of this master/slave */
765 int32_t reserved01; /* reserved for future master_id */
766 int32_t mirror_flags; /* misc flags */
767 char label[64]; /* filesystem space label */
768 char snapshots[64]; /* softlink dir for pruning */
769 int16_t prune_time; /* how long to spend pruning */
770 int16_t prune_freq; /* how often we prune */
771 int16_t reblock_time; /* how long to spend reblocking */
772 int16_t reblock_freq; /* how often we reblock */
773 int32_t snapshot_freq; /* how often we create a snapshot */
774 int32_t prune_min; /* do not prune recent history */
775 int32_t prune_max; /* do not retain history beyond here */
776 int32_t reserved[16];
779 typedef struct hammer_pseudofs_data *hammer_pseudofs_data_t;
781 #define HAMMER_PFSD_SLAVE 0x00000001
782 #define HAMMER_PFSD_DELETED 0x80000000
785 * Snapshot meta-data { Objid = HAMMER_OBJID_ROOT, Key = tid, rectype = SNAPSHOT }.
787 * Snapshot records replace the old <fs>/snapshots/<softlink> methodology. Snapshot
788 * records are mirrored but may be independantly managed once they are laid down on
791 * NOTE: The b-tree key is signed, the tid is not, so callers must still sort the
794 * NOTE: Reserved fields must be zero (as usual)
796 struct hammer_snapshot_data {
797 hammer_tid_t tid; /* the snapshot TID itself (== key) */
798 u_int64_t ts; /* real-time when snapshot was made */
799 u_int64_t reserved01;
800 u_int64_t reserved02;
801 char label[64]; /* user-supplied description */
802 u_int64_t reserved03[4];
806 * Config meta-data { ObjId = HAMMER_OBJID_ROOT, Key = 0, rectype = CONFIG }.
808 * Used to store the hammer cleanup config. This data is not mirrored.
810 struct hammer_config_data {
815 * Rollup various structures embedded as record data
817 union hammer_data_ondisk {
818 struct hammer_entry_data entry;
819 struct hammer_inode_data inode;
820 struct hammer_symlink_data symlink;
821 struct hammer_pseudofs_data pfsd;
822 struct hammer_snapshot_data snap;
823 struct hammer_config_data config;
826 typedef union hammer_data_ondisk *hammer_data_ondisk_t;