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>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
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
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * Hammer transction ids are 64 bit unsigned integers and are usually
96 * synchronized with the time of day in nanoseconds.
98 * Hammer offsets are used for FIFO indexing and embed a cycle counter
99 * and volume number in addition to the offset. Most offsets are required
100 * to be 64-byte aligned.
102 typedef u_int64_t hammer_tid_t;
103 typedef u_int64_t hammer_off_t;
104 typedef u_int32_t hammer_seq_t;
105 typedef u_int32_t hammer_crc_t;
107 #define HAMMER_MIN_TID 0ULL /* unsigned */
108 #define HAMMER_MAX_TID 0xFFFFFFFFFFFFFFFFULL /* unsigned */
109 #define HAMMER_MIN_KEY -0x8000000000000000LL /* signed */
110 #define HAMMER_MAX_KEY 0x7FFFFFFFFFFFFFFFLL /* signed */
111 #define HAMMER_MIN_OBJID HAMMER_MIN_KEY /* signed */
112 #define HAMMER_MAX_OBJID HAMMER_MAX_KEY /* signed */
113 #define HAMMER_MIN_RECTYPE 0x0U /* unsigned */
114 #define HAMMER_MAX_RECTYPE 0xFFFFU /* unsigned */
115 #define HAMMER_MIN_OFFSET 0ULL /* unsigned */
116 #define HAMMER_MAX_OFFSET 0xFFFFFFFFFFFFFFFFULL /* unsigned */
119 * hammer_off_t has several different encodings. Note that not all zones
122 * zone 0: reserved for sanity
123 * zone 1 (z,v,o): raw volume relative (offset 0 is the volume header)
124 * zone 2 (z,v,o): raw buffer relative (offset 0 is the first buffer)
125 * zone 3 (z,o): undo fifo - actually fixed phys array in vol hdr
126 * zone 4 (z,v,o): freemap - only real blockmap
127 * zone 8 (z,v,o): B-Tree - actually zone-2 address
128 * zone 9 (z,v,o): Record - actually zone-2 address
129 * zone 10 (z,v,o): Large-data - actually zone-2 address
130 * zone 15: reserved for sanity
132 * layer1/layer2 direct map:
133 * zzzzvvvvvvvvoooo oooooooooooooooo oooooooooooooooo oooooooooooooooo
134 * ----111111111111 1111112222222222 222222222ooooooo oooooooooooooooo
137 #define HAMMER_ZONE_RAW_VOLUME 0x1000000000000000ULL
138 #define HAMMER_ZONE_RAW_BUFFER 0x2000000000000000ULL
139 #define HAMMER_ZONE_UNDO 0x3000000000000000ULL
140 #define HAMMER_ZONE_FREEMAP 0x4000000000000000ULL
141 #define HAMMER_ZONE_RESERVED05 0x5000000000000000ULL
142 #define HAMMER_ZONE_RESERVED06 0x6000000000000000ULL
143 #define HAMMER_ZONE_RESERVED07 0x7000000000000000ULL
144 #define HAMMER_ZONE_BTREE 0x8000000000000000ULL
145 #define HAMMER_ZONE_META 0x9000000000000000ULL
146 #define HAMMER_ZONE_LARGE_DATA 0xA000000000000000ULL
147 #define HAMMER_ZONE_SMALL_DATA 0xB000000000000000ULL
148 #define HAMMER_ZONE_RESERVED0C 0xC000000000000000ULL
149 #define HAMMER_ZONE_RESERVED0D 0xD000000000000000ULL
150 #define HAMMER_ZONE_RESERVED0E 0xE000000000000000ULL
151 #define HAMMER_ZONE_UNAVAIL 0xF000000000000000ULL
153 #define HAMMER_ZONE_RAW_VOLUME_INDEX 1
154 #define HAMMER_ZONE_RAW_BUFFER_INDEX 2
155 #define HAMMER_ZONE_UNDO_INDEX 3
156 #define HAMMER_ZONE_FREEMAP_INDEX 4
157 #define HAMMER_ZONE_BTREE_INDEX 8
158 #define HAMMER_ZONE_META_INDEX 9
159 #define HAMMER_ZONE_LARGE_DATA_INDEX 10
160 #define HAMMER_ZONE_SMALL_DATA_INDEX 11
161 #define HAMMER_ZONE_UNAVAIL_INDEX 15 /* unavailable */
163 #define HAMMER_MAX_ZONES 16
165 #define HAMMER_VOL_ENCODE(vol_no) \
166 ((hammer_off_t)((vol_no) & 255) << 52)
167 #define HAMMER_VOL_DECODE(ham_off) \
168 (int32_t)(((hammer_off_t)(ham_off) >> 52) & 255)
169 #define HAMMER_ZONE_DECODE(ham_off) \
170 (int32_t)(((hammer_off_t)(ham_off) >> 60))
171 #define HAMMER_ZONE_ENCODE(zone, ham_off) \
172 (((hammer_off_t)(zone) << 60) | (ham_off))
173 #define HAMMER_SHORT_OFF_ENCODE(offset) \
174 ((hammer_off_t)(offset) & HAMMER_OFF_SHORT_MASK)
175 #define HAMMER_LONG_OFF_ENCODE(offset) \
176 ((hammer_off_t)(offset) & HAMMER_OFF_LONG_MASK)
178 #define HAMMER_ENCODE_RAW_VOLUME(vol_no, offset) \
179 (HAMMER_ZONE_RAW_VOLUME | \
180 HAMMER_VOL_ENCODE(vol_no) | \
181 HAMMER_SHORT_OFF_ENCODE(offset))
183 #define HAMMER_ENCODE_RAW_BUFFER(vol_no, offset) \
184 (HAMMER_ZONE_RAW_BUFFER | \
185 HAMMER_VOL_ENCODE(vol_no) | \
186 HAMMER_SHORT_OFF_ENCODE(offset))
188 #define HAMMER_ENCODE_FREEMAP(vol_no, offset) \
189 (HAMMER_ZONE_FREEMAP | \
190 HAMMER_VOL_ENCODE(vol_no) | \
191 HAMMER_SHORT_OFF_ENCODE(offset))
194 * Large-Block backing store
196 * A blockmap is a two-level map which translates a blockmap-backed zone
197 * offset into a raw zone 2 offset. Each layer handles 18 bits. The 8M
198 * large-block size is 23 bits so two layers gives us 23+18+18 = 59 bits
201 #define HAMMER_LARGEBLOCK_SIZE (8192 * 1024)
202 #define HAMMER_LARGEBLOCK_SIZE64 ((u_int64_t)HAMMER_LARGEBLOCK_SIZE)
203 #define HAMMER_LARGEBLOCK_MASK (HAMMER_LARGEBLOCK_SIZE - 1)
204 #define HAMMER_LARGEBLOCK_MASK64 ((u_int64_t)HAMMER_LARGEBLOCK_SIZE - 1)
205 #define HAMMER_LARGEBLOCK_BITS 23
206 #if (1 << HAMMER_LARGEBLOCK_BITS) != HAMMER_LARGEBLOCK_SIZE
207 #error "HAMMER_LARGEBLOCK_BITS BROKEN"
210 #define HAMMER_BUFFERS_PER_LARGEBLOCK \
211 (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE)
212 #define HAMMER_BUFFERS_PER_LARGEBLOCK_MASK \
213 (HAMMER_BUFFERS_PER_LARGEBLOCK - 1)
214 #define HAMMER_BUFFERS_PER_LARGEBLOCK_MASK64 \
215 ((hammer_off_t)HAMMER_BUFFERS_PER_LARGEBLOCK_MASK)
218 * Maximum number of mirrors operating in master mode (multi-master
219 * clustering and mirroring).
221 #define HAMMER_MAX_MASTERS 16
224 * The blockmap is somewhat of a degenerate structure. HAMMER only actually
225 * uses it in its original incarnation to implement the free-map.
227 * zone:1 raw volume (no blockmap)
228 * zone:2 raw buffer (no blockmap)
229 * zone:3 undo-map (direct layer2 array in volume header)
230 * zone:4 free-map (the only real blockmap)
231 * zone:8-15 zone id used to classify big-block only, address is actually
234 struct hammer_blockmap {
235 hammer_off_t phys_offset; /* zone-2 physical offset */
236 hammer_off_t first_offset; /* zone-X logical offset (zone 3) */
237 hammer_off_t next_offset; /* zone-X logical offset */
238 hammer_off_t alloc_offset; /* zone-X logical offset */
239 u_int32_t reserved01;
240 hammer_crc_t entry_crc;
243 typedef struct hammer_blockmap *hammer_blockmap_t;
245 #define HAMMER_BLOCKMAP_CRCSIZE \
246 offsetof(struct hammer_blockmap, entry_crc)
249 * The blockmap is a 2-layer entity made up of big-blocks. The first layer
250 * contains 262144 32-byte entries (18 bits), the second layer contains
251 * 524288 16-byte entries (19 bits), representing 8MB (23 bit) blockmaps.
252 * 18+19+23 = 60 bits. The top four bits are the zone id.
254 * Currently only the freemap utilizes both layers in all their glory.
255 * All primary data/meta-data zones actually encode a zone-2 address
256 * requiring no real blockmap translation.
258 * The freemap uses the upper 8 bits of layer-1 to identify the volume,
259 * thus any space allocated via the freemap can be directly translated
260 * to a zone:2 (or zone:8-15) address.
262 * zone-X blockmap offset: [z:4][layer1:18][layer2:19][bigblock:23]
264 struct hammer_blockmap_layer1 {
265 hammer_off_t blocks_free; /* big-blocks free */
266 hammer_off_t phys_offset; /* UNAVAIL or zone-2 */
267 hammer_off_t reserved01;
268 hammer_crc_t layer2_crc; /* xor'd crc's of HAMMER_BLOCKSIZE */
270 hammer_crc_t layer1_crc; /* MUST BE LAST FIELD OF STRUCTURE*/
273 typedef struct hammer_blockmap_layer1 *hammer_blockmap_layer1_t;
275 #define HAMMER_LAYER1_CRCSIZE \
276 offsetof(struct hammer_blockmap_layer1, layer1_crc)
278 struct hammer_blockmap_layer2 {
279 u_int8_t zone; /* typed allocation zone */
282 u_int32_t append_off; /* allocatable space index */
283 u_int32_t bytes_free; /* bytes free within this bigblock */
284 hammer_crc_t entry_crc;
287 typedef struct hammer_blockmap_layer2 *hammer_blockmap_layer2_t;
289 #define HAMMER_LAYER2_CRCSIZE \
290 offsetof(struct hammer_blockmap_layer2, entry_crc)
292 #define HAMMER_BLOCKMAP_FREE 0ULL
293 #define HAMMER_BLOCKMAP_UNAVAIL ((hammer_off_t)-1LL)
295 #define HAMMER_BLOCKMAP_RADIX1 /* 262144 (18) */ \
296 (HAMMER_LARGEBLOCK_SIZE / sizeof(struct hammer_blockmap_layer1))
297 #define HAMMER_BLOCKMAP_RADIX2 /* 524288 (19) */ \
298 (HAMMER_LARGEBLOCK_SIZE / sizeof(struct hammer_blockmap_layer2))
300 #define HAMMER_BLOCKMAP_RADIX1_PERBUFFER \
301 (HAMMER_BLOCKMAP_RADIX1 / (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE))
302 #define HAMMER_BLOCKMAP_RADIX2_PERBUFFER \
303 (HAMMER_BLOCKMAP_RADIX2 / (HAMMER_LARGEBLOCK_SIZE / HAMMER_BUFSIZE))
305 #define HAMMER_BLOCKMAP_LAYER1 /* 18+19+23 */ \
306 (HAMMER_BLOCKMAP_RADIX1 * HAMMER_BLOCKMAP_LAYER2)
307 #define HAMMER_BLOCKMAP_LAYER2 /* 19+23 - 4TB */ \
308 (HAMMER_BLOCKMAP_RADIX2 * HAMMER_LARGEBLOCK_SIZE64)
310 #define HAMMER_BLOCKMAP_LAYER1_MASK (HAMMER_BLOCKMAP_LAYER1 - 1)
311 #define HAMMER_BLOCKMAP_LAYER2_MASK (HAMMER_BLOCKMAP_LAYER2 - 1)
314 * byte offset within layer1 or layer2 big-block for the entry representing
315 * a zone-2 physical offset.
317 #define HAMMER_BLOCKMAP_LAYER1_OFFSET(zone2_offset) \
318 (((zone2_offset) & HAMMER_BLOCKMAP_LAYER1_MASK) / \
319 HAMMER_BLOCKMAP_LAYER2 * sizeof(struct hammer_blockmap_layer1))
321 #define HAMMER_BLOCKMAP_LAYER2_OFFSET(zone2_offset) \
322 (((zone2_offset) & HAMMER_BLOCKMAP_LAYER2_MASK) / \
323 HAMMER_LARGEBLOCK_SIZE64 * sizeof(struct hammer_blockmap_layer2))
326 * HAMMER UNDO parameters. The UNDO fifo is mapped directly in the volume
327 * header with an array of layer2 structures. A maximum of (128x8MB) = 1GB
328 * may be reserved. The size of the undo fifo is usually set a newfs time
329 * but can be adjusted if the filesystem is taken offline.
332 #define HAMMER_UNDO_LAYER2 128 /* max layer2 undo mapping entries */
335 * All on-disk HAMMER structures which make up elements of the UNDO FIFO
336 * contain a hammer_fifo_head and hammer_fifo_tail structure. This structure
337 * contains all the information required to validate the fifo element
338 * and to scan the fifo in either direction. The head is typically embedded
339 * in higher level hammer on-disk structures while the tail is typically
340 * out-of-band. hdr_size is the size of the whole mess, including the tail.
342 * All undo structures are guaranteed to not cross a 16K filesystem
343 * buffer boundary. Most undo structures are fairly small. Data spaces
344 * are not immediately reused by HAMMER so file data is not usually recorded
345 * as part of an UNDO.
347 * PAD elements are allowed to take up only 8 bytes of space as a special
348 * case, containing only hdr_signature, hdr_type, and hdr_size fields,
349 * and with the tail overloaded onto the head structure for 8 bytes total.
351 * Every undo record has a sequence number. This number is unrelated to
352 * transaction ids and instead collects the undo transactions associated
353 * with a single atomic operation. A larger transactional operation, such
354 * as a remove(), may consist of several smaller atomic operations
355 * representing raw meta-data operations.
357 #define HAMMER_HEAD_ONDISK_SIZE 32
358 #define HAMMER_HEAD_ALIGN 8
359 #define HAMMER_HEAD_ALIGN_MASK (HAMMER_HEAD_ALIGN - 1)
360 #define HAMMER_TAIL_ONDISK_SIZE 8
361 #define HAMMER_HEAD_DOALIGN(bytes) \
362 (((bytes) + HAMMER_HEAD_ALIGN_MASK) & ~HAMMER_HEAD_ALIGN_MASK)
364 struct hammer_fifo_head {
365 u_int16_t hdr_signature;
367 u_int32_t hdr_size; /* aligned size of the whole mess */
368 u_int32_t reserved01; /* (0) reserved for future use */
369 hammer_crc_t hdr_crc; /* XOR crc up to field w/ crc after field */
372 #define HAMMER_FIFO_HEAD_CRCOFF offsetof(struct hammer_fifo_head, hdr_crc)
374 struct hammer_fifo_tail {
375 u_int16_t tail_signature;
377 u_int32_t tail_size; /* aligned size of the whole mess */
380 typedef struct hammer_fifo_head *hammer_fifo_head_t;
381 typedef struct hammer_fifo_tail *hammer_fifo_tail_t;
386 #define HAMMER_HEAD_TYPE_PAD (0x0040U|HAMMER_HEAD_FLAG_FREE)
387 #define HAMMER_HEAD_TYPE_VOL 0x0041U /* Volume (dummy header) */
388 #define HAMMER_HEAD_TYPE_BTREE 0x0042U /* B-Tree node */
389 #define HAMMER_HEAD_TYPE_UNDO 0x0043U /* random UNDO information */
390 #define HAMMER_HEAD_TYPE_DELETE 0x0044U /* record deletion */
391 #define HAMMER_HEAD_TYPE_RECORD 0x0045U /* Filesystem record */
393 #define HAMMER_HEAD_FLAG_FREE 0x8000U /* Indicates object freed */
395 #define HAMMER_HEAD_SIGNATURE 0xC84EU
396 #define HAMMER_TAIL_SIGNATURE 0xC74FU
398 #define HAMMER_HEAD_SEQ_BEG 0x80000000U
399 #define HAMMER_HEAD_SEQ_END 0x40000000U
400 #define HAMMER_HEAD_SEQ_MASK 0x3FFFFFFFU
403 * Misc FIFO structures.
405 struct hammer_fifo_undo {
406 struct hammer_fifo_head head;
407 hammer_off_t undo_offset; /* zone-1 offset */
408 int32_t undo_data_bytes;
409 int32_t undo_reserved01;
410 /* followed by data */
413 typedef struct hammer_fifo_undo *hammer_fifo_undo_t;
415 struct hammer_fifo_buf_commit {
416 hammer_off_t undo_offset;
420 * Volume header types
422 #define HAMMER_FSBUF_VOLUME 0xC8414D4DC5523031ULL /* HAMMER01 */
423 #define HAMMER_FSBUF_VOLUME_REV 0x313052C54D4D41C8ULL /* (reverse endian) */
426 * The B-Tree structures need hammer_fsbuf_head.
428 #include "hammer_btree.h"
431 * HAMMER Volume header
433 * A HAMMER filesystem is built from any number of block devices, Each block
434 * device contains a volume header followed by however many buffers fit
437 * One of the volumes making up a HAMMER filesystem is the master, the
438 * rest are slaves. It does not have to be volume #0.
440 * The volume header takes up an entire 16K filesystem buffer and may
441 * represent up to 64KTB (65536 TB) of space.
443 * Special field notes:
445 * vol_bot_beg - offset of boot area (mem_beg - bot_beg bytes)
446 * vol_mem_beg - offset of memory log (clu_beg - mem_beg bytes)
447 * vol_buf_beg - offset of the first buffer.
449 * The memory log area allows a kernel to cache new records and data
450 * in memory without allocating space in the actual filesystem to hold
451 * the records and data. In the event that a filesystem becomes full,
452 * any records remaining in memory can be flushed to the memory log
453 * area. This allows the kernel to immediately return success.
456 #define HAMMER_BOOT_MINBYTES (32*1024)
457 #define HAMMER_BOOT_NOMBYTES (64LL*1024*1024)
458 #define HAMMER_BOOT_MAXBYTES (256LL*1024*1024)
460 #define HAMMER_MEM_MINBYTES (256*1024)
461 #define HAMMER_MEM_NOMBYTES (1LL*1024*1024*1024)
462 #define HAMMER_MEM_MAXBYTES (64LL*1024*1024*1024)
464 struct hammer_volume_ondisk {
465 u_int64_t vol_signature;/* Signature */
467 int64_t vol_bot_beg; /* byte offset of boot area or 0 */
468 int64_t vol_mem_beg; /* byte offset of memory log or 0 */
469 int64_t vol_buf_beg; /* byte offset of first buffer in volume */
470 int64_t vol_buf_end; /* byte offset of volume EOF (on buf bndry) */
471 int64_t vol_locked; /* reserved clusters are >= this offset */
473 uuid_t vol_fsid; /* identify filesystem */
474 uuid_t vol_fstype; /* identify filesystem type */
475 char vol_name[64]; /* Name of volume */
477 int32_t vol_no; /* volume number within filesystem */
478 int32_t vol_count; /* number of volumes making up FS */
480 u_int32_t vol_version; /* version control information */
481 hammer_crc_t vol_crc; /* header crc */
482 u_int32_t vol_flags; /* volume flags */
483 u_int32_t vol_rootvol; /* which volume is the root volume? */
485 int32_t vol_reserved04;
486 int32_t vol_reserved05;
487 u_int32_t vol_reserved06;
488 u_int32_t vol_reserved07;
490 int32_t vol_blocksize; /* for statfs only */
491 int32_t vol_reserved08;
492 int64_t vol_nblocks; /* total allocatable hammer bufs */
495 * These fields are initialized and space is reserved in every
496 * volume making up a HAMMER filesytem, but only the master volume
497 * contains valid data.
499 int64_t vol0_stat_bigblocks; /* total bigblocks when fs is empty */
500 int64_t vol0_stat_freebigblocks;/* number of free bigblocks */
501 int64_t vol0_stat_bytes; /* for statfs only */
502 int64_t vol0_stat_inodes; /* for statfs only */
503 int64_t vol0_stat_records; /* total records in filesystem */
504 hammer_off_t vol0_btree_root; /* B-Tree root */
505 hammer_tid_t vol0_next_tid; /* highest partially synchronized TID */
506 hammer_off_t vol0_unused03;
509 * Blockmaps for zones. Not all zones use a blockmap. Note that
510 * the entire root blockmap is cached in the hammer_mount structure.
512 struct hammer_blockmap vol0_blockmap[HAMMER_MAX_ZONES];
515 * Array of zone-2 addresses for undo FIFO.
517 hammer_off_t vol0_undo_array[HAMMER_UNDO_LAYER2];
521 typedef struct hammer_volume_ondisk *hammer_volume_ondisk_t;
523 #define HAMMER_VOLF_VALID 0x0001 /* valid entry */
524 #define HAMMER_VOLF_OPEN 0x0002 /* volume is open */
525 #define HAMMER_VOLF_NEEDFLUSH 0x0004 /* volume needs flush */
527 #define HAMMER_VOL_CRCSIZE1 \
528 offsetof(struct hammer_volume_ondisk, vol_crc)
529 #define HAMMER_VOL_CRCSIZE2 \
530 (sizeof(struct hammer_volume_ondisk) - HAMMER_VOL_CRCSIZE1 - \
531 sizeof(hammer_crc_t))
533 #define HAMMER_VOL_VERSION_MIN 1 /* minimum supported version */
534 #define HAMMER_VOL_VERSION_DEFAULT 1 /* newfs default version */
535 #define HAMMER_VOL_VERSION_WIP 2 /* version >= this is WIP */
536 #define HAMMER_VOL_VERSION_MAX 2 /* maximum supported version */
538 #define HAMMER_VOL_VERSION_ONE 1
539 #define HAMMER_VOL_VERSION_TWO 2
541 * Record types are fairly straightforward. The B-Tree includes the record
542 * type in its index sort.
544 #define HAMMER_RECTYPE_UNKNOWN 0
545 #define HAMMER_RECTYPE_LOWEST 1 /* lowest record type avail */
546 #define HAMMER_RECTYPE_INODE 1 /* inode in obj_id space */
547 #define HAMMER_RECTYPE_UNUSED02 2
548 #define HAMMER_RECTYPE_UNUSED03 3
549 #define HAMMER_RECTYPE_DATA 0x0010
550 #define HAMMER_RECTYPE_DIRENTRY 0x0011
551 #define HAMMER_RECTYPE_DB 0x0012
552 #define HAMMER_RECTYPE_EXT 0x0013 /* ext attributes */
553 #define HAMMER_RECTYPE_FIX 0x0014 /* fixed attribute */
554 #define HAMMER_RECTYPE_PFS 0x0015 /* PFS management */
555 #define HAMMER_RECTYPE_MOVED 0x8000 /* special recovery flag */
556 #define HAMMER_RECTYPE_MAX 0xFFFF
558 #define HAMMER_RECTYPE_CLEAN_START HAMMER_RECTYPE_EXT
560 #define HAMMER_FIXKEY_SYMLINK 1
562 #define HAMMER_OBJTYPE_UNKNOWN 0 /* (never exists on-disk) */
563 #define HAMMER_OBJTYPE_DIRECTORY 1
564 #define HAMMER_OBJTYPE_REGFILE 2
565 #define HAMMER_OBJTYPE_DBFILE 3
566 #define HAMMER_OBJTYPE_FIFO 4
567 #define HAMMER_OBJTYPE_CDEV 5
568 #define HAMMER_OBJTYPE_BDEV 6
569 #define HAMMER_OBJTYPE_SOFTLINK 7
570 #define HAMMER_OBJTYPE_PSEUDOFS 8 /* pseudo filesystem obj */
571 #define HAMMER_OBJTYPE_SOCKET 9
574 * HAMMER inode attribute data
576 * The data reference for a HAMMER inode points to this structure. Any
577 * modifications to the contents of this structure will result in a
578 * replacement operation.
580 * parent_obj_id is only valid for directories (which cannot be hard-linked),
581 * and specifies the parent directory obj_id. This field will also be set
582 * for non-directory inodes as a recovery aid, but can wind up holding
583 * stale information. However, since object id's are not reused, the worse
584 * that happens is that the recovery code is unable to use it.
586 * NOTE: Future note on directory hardlinks. We can implement a record type
587 * which allows us to point to multiple parent directories.
589 * NOTE: atime is stored in the inode's B-Tree element and not in the inode
590 * data. This allows the atime to be updated without having to lay down a
593 struct hammer_inode_data {
594 u_int16_t version; /* inode data version */
595 u_int16_t mode; /* basic unix permissions */
596 u_int32_t uflags; /* chflags */
597 u_int32_t rmajor; /* used by device nodes */
598 u_int32_t rminor; /* used by device nodes */
600 int64_t parent_obj_id; /* parent directory obj_id */
605 u_int8_t cap_flags; /* capability support flags (extension) */
606 u_int16_t reserved02;
607 u_int32_t reserved03; /* RESERVED FOR POSSIBLE FUTURE BIRTHTIME */
608 u_int64_t nlinks; /* hard links */
609 u_int64_t size; /* filesystem object size */
613 u_int32_t parent_obj_localization;
614 u_int32_t integrity_crc;
616 char symlink[24]; /* HAMMER_INODE_BASESYMLEN */
618 u_int64_t mtime; /* mtime must be second-to-last */
619 u_int64_t atime; /* atime must be last */
623 * Neither mtime nor atime upates are CRCd by the B-Tree element.
624 * mtime updates have UNDO, atime updates do not.
626 #define HAMMER_ITIMES_BASE(ino_data) (&(ino_data)->mtime)
627 #define HAMMER_ITIMES_BYTES (sizeof(u_int64_t) * 2)
629 #define HAMMER_INODE_CRCSIZE \
630 offsetof(struct hammer_inode_data, mtime)
632 #define HAMMER_INODE_DATA_VERSION 1
633 #define HAMMER_OBJID_ROOT 1
634 #define HAMMER_INODE_BASESYMLEN 24 /* see ext.symlink */
637 * Capability & implementation flags.
639 #define HAMMER_INODE_CAP_DIRHASH_MASK 0x03 /* directory: hash algorithm */
640 #define HAMMER_INODE_CAP_DIRHASH_ALG0 0x00
641 #define HAMMER_INODE_CAP_DIRHASH_ALG1 0x01
642 #define HAMMER_INODE_CAP_DIRHASH_ALG2 0x02
643 #define HAMMER_INODE_CAP_DIRHASH_ALG3 0x03
646 * A HAMMER directory entry associates a HAMMER filesystem object with a
647 * namespace. It is possible to hook into a pseudo-filesystem (with its
648 * own inode numbering space) in the filesystem by setting the high
649 * 16 bits of the localization field. The low 16 bits must be 0 and
650 * are reserved for future use.
652 * Directory entries are indexed with a 128 bit namekey rather then an
653 * offset. A portion of the namekey is an iterator/randomizer to deal
656 * NOTE: base.base.obj_type from the related B-Tree leaf entry holds
657 * the filesystem object type of obj_id, e.g. a den_type equivalent.
658 * It is not stored in hammer_entry_data.
660 * NOTE: den_name / the filename data reference is NOT terminated with \0.
662 struct hammer_entry_data {
663 int64_t obj_id; /* object being referenced */
664 u_int32_t localization; /* identify pseudo-filesystem */
665 u_int32_t reserved02;
666 char name[16]; /* name (extended) */
669 #define HAMMER_ENTRY_NAME_OFF offsetof(struct hammer_entry_data, name[0])
670 #define HAMMER_ENTRY_SIZE(nlen) offsetof(struct hammer_entry_data, name[nlen])
673 * Symlink data which does not fit in the inode is stored in a separte
676 struct hammer_symlink_data {
680 #define HAMMER_SYMLINK_NAME_OFF offsetof(struct hammer_symlink_data, name[0])
683 * The root inode for the primary filesystem and root inode for any
684 * pseudo-fs may be tagged with an optional data structure using
685 * HAMMER_RECTYPE_FIX/HAMMER_FIXKEY_PSEUDOFS. This structure allows
686 * the node to be used as a mirroring master or slave.
688 * When operating as a slave CD's into the node automatically become read-only
689 * and as-of sync_end_tid.
691 * When operating as a master the read PFSD info sets sync_end_tid to
692 * the most recently flushed TID.
694 * sync_low_tid is not yet used but will represent the highest pruning
695 * end-point, after which full history is available.
697 struct hammer_pseudofs_data {
698 hammer_tid_t sync_low_tid; /* full history beyond this point */
699 hammer_tid_t sync_beg_tid; /* earliest tid w/ full history avail */
700 hammer_tid_t sync_end_tid; /* current synchronizatoin point */
701 u_int64_t sync_beg_ts; /* real-time of last completed sync */
702 u_int64_t sync_end_ts; /* initiation of current sync cycle */
703 uuid_t shared_uuid; /* shared uuid (match required) */
704 uuid_t unique_uuid; /* unique uuid of this master/slave */
705 int32_t reserved01; /* reserved for future master_id */
706 int32_t mirror_flags; /* misc flags */
707 char label[64]; /* filesystem space label */
708 char snapshots[64]; /* softlink dir for pruning */
709 int16_t prune_time; /* how long to spend pruning */
710 int16_t prune_freq; /* how often we prune */
711 int16_t reblock_time; /* how long to spend reblocking */
712 int16_t reblock_freq; /* how often we reblock */
713 int32_t snapshot_freq; /* how often we create a snapshot */
714 int32_t prune_min; /* do not prune recent history */
715 int32_t prune_max; /* do not retain history beyond here */
716 int32_t reserved[16];
719 typedef struct hammer_pseudofs_data *hammer_pseudofs_data_t;
721 #define HAMMER_PFSD_SLAVE 0x00000001
722 #define HAMMER_PFSD_DELETED 0x80000000
725 * Rollup various structures embedded as record data
727 union hammer_data_ondisk {
728 struct hammer_entry_data entry;
729 struct hammer_inode_data inode;
730 struct hammer_symlink_data symlink;
731 struct hammer_pseudofs_data pfsd;
734 typedef union hammer_data_ondisk *hammer_data_ondisk_t;