xref: /dragonfly/sys/vfs/hammer/hammer_disk.h (revision b29f78b5)
1 /*
2  * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
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
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
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
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $DragonFly: src/sys/vfs/hammer/hammer_disk.h,v 1.55 2008/11/13 02:18:43 dillon Exp $
35  */
36 
37 #ifndef VFS_HAMMER_DISK_H_
38 #define VFS_HAMMER_DISK_H_
39 
40 #ifndef _SYS_UUID_H_
41 #include <sys/uuid.h>
42 #endif
43 
44 /*
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.
49  *
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.
55  *
56  * A HAMMER filesystem may span multiple volumes.
57  *
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.
62  *
63  * 64K X-bufs are used for blocks >= a file's 1MB mark.
64  *
65  * Per-volume storage limit: 52 bits		4096 TB
66  * Per-Zone storage limit: 60 bits		1 MTB
67  * Per-filesystem storage limit: 60 bits	1 MTB
68  */
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
75 
76 #if (1 << HAMMER_BUFFER_BITS) != HAMMER_BUFSIZE
77 #error "HAMMER_BUFFER_BITS BROKEN"
78 #endif
79 
80 #define HAMMER_BUFSIZE64	((u_int64_t)HAMMER_BUFSIZE)
81 #define HAMMER_BUFMASK64	((u_int64_t)HAMMER_BUFMASK)
82 
83 #define HAMMER_XBUFSIZE64	((u_int64_t)HAMMER_XBUFSIZE)
84 #define HAMMER_XBUFMASK64	((u_int64_t)HAMMER_XBUFMASK)
85 
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
93 
94 #define HAMMER_OFF_BAD		((hammer_off_t)-1)
95 
96 /*
97  * The current limit of volumes that can make up a HAMMER FS
98  */
99 #define HAMMER_MAX_VOLUMES	256
100 
101 /*
102  * Hammer transction ids are 64 bit unsigned integers and are usually
103  * synchronized with the time of day in nanoseconds.
104  *
105  * Hammer offsets are used for FIFO indexing and embed a cycle counter
106  * and volume number in addition to the offset.  Most offsets are required
107  * to be 16 KB aligned.
108  */
109 typedef u_int64_t hammer_tid_t;
110 typedef u_int64_t hammer_off_t;
111 typedef u_int32_t hammer_seq_t;
112 typedef u_int32_t hammer_crc_t;
113 
114 #define HAMMER_MIN_TID		0ULL			/* unsigned */
115 #define HAMMER_MAX_TID		0xFFFFFFFFFFFFFFFFULL	/* unsigned */
116 #define HAMMER_MIN_KEY		-0x8000000000000000LL	/* signed */
117 #define HAMMER_MAX_KEY		0x7FFFFFFFFFFFFFFFLL	/* signed */
118 #define HAMMER_MIN_OBJID	HAMMER_MIN_KEY		/* signed */
119 #define HAMMER_MAX_OBJID	HAMMER_MAX_KEY		/* signed */
120 #define HAMMER_MIN_RECTYPE	0x0U			/* unsigned */
121 #define HAMMER_MAX_RECTYPE	0xFFFFU			/* unsigned */
122 #define HAMMER_MIN_OFFSET	0ULL			/* unsigned */
123 #define HAMMER_MAX_OFFSET	0xFFFFFFFFFFFFFFFFULL	/* unsigned */
124 
125 /*
126  * hammer_off_t has several different encodings.  Note that not all zones
127  * encode a vol_no.
128  *
129  * zone 0:		reserved for sanity
130  * zone 1 (z,v,o):	raw volume relative (offset 0 is the volume header)
131  * zone 2 (z,v,o):	raw buffer relative (offset 0 is the first buffer)
132  * zone 3 (z,o):	undo fifo	- actually fixed phys array in vol hdr
133  * zone 4 (z,v,o):	freemap		- only real blockmap
134  * zone 8 (z,v,o):	B-Tree		- actually zone-2 address
135  * zone 9 (z,v,o):	Record		- actually zone-2 address
136  * zone 10 (z,v,o):	Large-data	- actually zone-2 address
137  * zone 11 (z,v,o):	Small-data	- actually zone-2 address
138  * zone 15:		reserved for sanity
139  *
140  * layer1/layer2 direct map:
141  *	zzzzvvvvvvvvoooo oooooooooooooooo oooooooooooooooo oooooooooooooooo
142  *	----111111111111 1111112222222222 222222222ooooooo oooooooooooooooo
143  */
144 
145 #define HAMMER_ZONE_RAW_VOLUME		0x1000000000000000ULL
146 #define HAMMER_ZONE_RAW_BUFFER		0x2000000000000000ULL
147 #define HAMMER_ZONE_UNDO		0x3000000000000000ULL
148 #define HAMMER_ZONE_FREEMAP		0x4000000000000000ULL
149 #define HAMMER_ZONE_RESERVED05		0x5000000000000000ULL
150 #define HAMMER_ZONE_RESERVED06		0x6000000000000000ULL
151 #define HAMMER_ZONE_RESERVED07		0x7000000000000000ULL
152 #define HAMMER_ZONE_BTREE		0x8000000000000000ULL
153 #define HAMMER_ZONE_META		0x9000000000000000ULL
154 #define HAMMER_ZONE_LARGE_DATA		0xA000000000000000ULL
155 #define HAMMER_ZONE_SMALL_DATA		0xB000000000000000ULL
156 #define HAMMER_ZONE_RESERVED0C		0xC000000000000000ULL
157 #define HAMMER_ZONE_RESERVED0D		0xD000000000000000ULL
158 #define HAMMER_ZONE_RESERVED0E		0xE000000000000000ULL
159 #define HAMMER_ZONE_UNAVAIL		0xF000000000000000ULL
160 
161 #define HAMMER_ZONE_RAW_VOLUME_INDEX	1
162 #define HAMMER_ZONE_RAW_BUFFER_INDEX	2
163 #define HAMMER_ZONE_UNDO_INDEX		3
164 #define HAMMER_ZONE_FREEMAP_INDEX	4
165 #define HAMMER_ZONE_BTREE_INDEX		8
166 #define HAMMER_ZONE_META_INDEX		9
167 #define HAMMER_ZONE_LARGE_DATA_INDEX	10
168 #define HAMMER_ZONE_SMALL_DATA_INDEX	11
169 #define HAMMER_ZONE_UNAVAIL_INDEX	15	/* unavailable */
170 
171 #define HAMMER_MAX_ZONES		16
172 
173 #define HAMMER_VOL_ENCODE(vol_no)			\
174 	((hammer_off_t)((vol_no) & 255) << 52)
175 #define HAMMER_VOL_DECODE(ham_off)			\
176 	(int32_t)(((hammer_off_t)(ham_off) >> 52) & 255)
177 #define HAMMER_ZONE_DECODE(ham_off)			\
178 	(int32_t)(((hammer_off_t)(ham_off) >> 60))
179 #define HAMMER_ZONE_ENCODE(zone, ham_off)		\
180 	(((hammer_off_t)(zone) << 60) | (ham_off))
181 #define HAMMER_SHORT_OFF_ENCODE(offset)			\
182 	((hammer_off_t)(offset) & HAMMER_OFF_SHORT_MASK)
183 #define HAMMER_LONG_OFF_ENCODE(offset)			\
184 	((hammer_off_t)(offset) & HAMMER_OFF_LONG_MASK)
185 
186 #define HAMMER_ENCODE_RAW_VOLUME(vol_no, offset)	\
187 	(HAMMER_ZONE_RAW_VOLUME |			\
188 	HAMMER_VOL_ENCODE(vol_no) |			\
189 	HAMMER_SHORT_OFF_ENCODE(offset))
190 
191 #define HAMMER_ENCODE_RAW_BUFFER(vol_no, offset)	\
192 	(HAMMER_ZONE_RAW_BUFFER |			\
193 	HAMMER_VOL_ENCODE(vol_no) |			\
194 	HAMMER_SHORT_OFF_ENCODE(offset))
195 
196 #define HAMMER_ENCODE_FREEMAP(vol_no, offset)		\
197 	(HAMMER_ZONE_FREEMAP |				\
198 	HAMMER_VOL_ENCODE(vol_no) |			\
199 	HAMMER_SHORT_OFF_ENCODE(offset))
200 
201 /*
202  * Big-Block backing store
203  *
204  * A blockmap is a two-level map which translates a blockmap-backed zone
205  * offset into a raw zone 2 offset.  The layer 1 handles 18 bits and the
206  * layer 2 handles 19 bits.  The 8M big-block size is 23 bits so two
207  * layers gives us 18+19+23 = 60 bits of address space.
208  *
209  * When using hinting for a blockmap lookup, the hint is lost when the
210  * scan leaves the HINTBLOCK, which is typically several BIGBLOCK's.
211  * HINTBLOCK is a heuristic.
212  */
213 #define HAMMER_HINTBLOCK_SIZE		(HAMMER_BIGBLOCK_SIZE * 4)
214 #define HAMMER_HINTBLOCK_MASK64		((u_int64_t)HAMMER_HINTBLOCK_SIZE - 1)
215 #define HAMMER_BIGBLOCK_SIZE		(8192 * 1024)
216 #define HAMMER_BIGBLOCK_OVERFILL	(6144 * 1024)
217 #define HAMMER_BIGBLOCK_SIZE64		((u_int64_t)HAMMER_BIGBLOCK_SIZE)
218 #define HAMMER_BIGBLOCK_MASK		(HAMMER_BIGBLOCK_SIZE - 1)
219 #define HAMMER_BIGBLOCK_MASK64		((u_int64_t)HAMMER_BIGBLOCK_SIZE - 1)
220 #define HAMMER_BIGBLOCK_BITS		23
221 #if (1 << HAMMER_BIGBLOCK_BITS) != HAMMER_BIGBLOCK_SIZE
222 #error "HAMMER_BIGBLOCK_BITS BROKEN"
223 #endif
224 
225 #define HAMMER_BUFFERS_PER_BIGBLOCK			\
226 	(HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE)
227 #define HAMMER_BUFFERS_PER_BIGBLOCK_MASK		\
228 	(HAMMER_BUFFERS_PER_BIGBLOCK - 1)
229 #define HAMMER_BUFFERS_PER_BIGBLOCK_MASK64		\
230 	((hammer_off_t)HAMMER_BUFFERS_PER_BIGBLOCK_MASK)
231 
232 /*
233  * Maximum number of mirrors operating in master mode (multi-master
234  * clustering and mirroring).
235  */
236 #define HAMMER_MAX_MASTERS		16
237 
238 /*
239  * The blockmap is somewhat of a degenerate structure.  HAMMER only actually
240  * uses it in its original incarnation to implement the free-map.
241  *
242  * zone:1	raw volume (no blockmap)
243  * zone:2	raw buffer (no blockmap)
244  * zone:3	undo-map   (direct layer2 array in volume header)
245  * zone:4	free-map   (the only real blockmap)
246  * zone:8-15	zone id used to classify big-block only, address is actually
247  *		a zone-2 address.
248  */
249 struct hammer_blockmap {
250 	hammer_off_t	phys_offset;    /* zone-2 physical offset */
251 	hammer_off_t	first_offset;	/* zone-X logical offset (zone 3) */
252 	hammer_off_t	next_offset;	/* zone-X logical offset */
253 	hammer_off_t	alloc_offset;	/* zone-X logical offset */
254 	u_int32_t	reserved01;
255 	hammer_crc_t	entry_crc;
256 };
257 
258 typedef struct hammer_blockmap *hammer_blockmap_t;
259 
260 #define HAMMER_BLOCKMAP_CRCSIZE	\
261 	offsetof(struct hammer_blockmap, entry_crc)
262 
263 /*
264  * The blockmap is a 2-layer entity made up of big-blocks.  The first layer
265  * contains 262144 32-byte entries (18 bits), the second layer contains
266  * 524288 16-byte entries (19 bits), representing 8MB (23 bit) blockmaps.
267  * 18+19+23 = 60 bits.  The top four bits are the zone id.
268  *
269  * Currently only the freemap utilizes both layers in all their glory.
270  * All primary data/meta-data zones actually encode a zone-2 address
271  * requiring no real blockmap translation.
272  *
273  * The freemap uses the upper 8 bits of layer-1 to identify the volume,
274  * thus any space allocated via the freemap can be directly translated
275  * to a zone:2 (or zone:8-15) address.
276  *
277  * zone-X blockmap offset: [zone:4][layer1:18][layer2:19][bigblock:23]
278  */
279 struct hammer_blockmap_layer1 {
280 	hammer_off_t	blocks_free;	/* big-blocks free */
281 	hammer_off_t	phys_offset;	/* UNAVAIL or zone-2 */
282 	hammer_off_t	reserved01;
283 	hammer_crc_t	layer2_crc;	/* xor'd crc's of HAMMER_BLOCKSIZE */
284 					/* (not yet used) */
285 	hammer_crc_t	layer1_crc;	/* MUST BE LAST FIELD OF STRUCTURE*/
286 };
287 
288 typedef struct hammer_blockmap_layer1 *hammer_blockmap_layer1_t;
289 
290 #define HAMMER_LAYER1_CRCSIZE	\
291 	offsetof(struct hammer_blockmap_layer1, layer1_crc)
292 
293 /*
294  * layer2 entry for 8MB bigblock.
295  *
296  * NOTE: bytes_free is signed and can legally go negative if/when data
297  *	 de-dup occurs.  This field will never go higher than
298  *	 HAMMER_BIGBLOCK_SIZE.  If exactly HAMMER_BIGBLOCK_SIZE
299  *	 the big-block is completely free.
300  */
301 struct hammer_blockmap_layer2 {
302 	u_int8_t	zone;		/* typed allocation zone */
303 	u_int8_t	unused01;
304 	u_int16_t	unused02;
305 	u_int32_t	append_off;	/* allocatable space index */
306 	int32_t		bytes_free;	/* bytes free within this bigblock */
307 	hammer_crc_t	entry_crc;
308 };
309 
310 typedef struct hammer_blockmap_layer2 *hammer_blockmap_layer2_t;
311 
312 #define HAMMER_LAYER2_CRCSIZE	\
313 	offsetof(struct hammer_blockmap_layer2, entry_crc)
314 
315 #define HAMMER_BLOCKMAP_FREE	0ULL
316 #define HAMMER_BLOCKMAP_UNAVAIL	((hammer_off_t)-1LL)
317 
318 #define HAMMER_BLOCKMAP_RADIX1	/* 262144 (18) */	\
319 	(HAMMER_BIGBLOCK_SIZE / sizeof(struct hammer_blockmap_layer1))
320 #define HAMMER_BLOCKMAP_RADIX2	/* 524288 (19) */	\
321 	(HAMMER_BIGBLOCK_SIZE / sizeof(struct hammer_blockmap_layer2))
322 
323 #define HAMMER_BLOCKMAP_RADIX1_PERBUFFER	\
324 	(HAMMER_BLOCKMAP_RADIX1 / (HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE))
325 #define HAMMER_BLOCKMAP_RADIX2_PERBUFFER	\
326 	(HAMMER_BLOCKMAP_RADIX2 / (HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE))
327 
328 #define HAMMER_BLOCKMAP_LAYER1	/* 18+19+23 - 1EB */		\
329 	(HAMMER_BLOCKMAP_RADIX1 * HAMMER_BLOCKMAP_LAYER2)
330 #define HAMMER_BLOCKMAP_LAYER2	/* 19+23 - 4TB */		\
331 	(HAMMER_BLOCKMAP_RADIX2 * HAMMER_BIGBLOCK_SIZE64)
332 
333 #define HAMMER_BLOCKMAP_LAYER1_MASK	(HAMMER_BLOCKMAP_LAYER1 - 1)
334 #define HAMMER_BLOCKMAP_LAYER2_MASK	(HAMMER_BLOCKMAP_LAYER2 - 1)
335 
336 /*
337  * byte offset within layer1 or layer2 big-block for the entry representing
338  * a zone-2 physical offset.
339  */
340 #define HAMMER_BLOCKMAP_LAYER1_OFFSET(zone2_offset)	\
341 	(((zone2_offset) & HAMMER_BLOCKMAP_LAYER1_MASK) / 	\
342 	 HAMMER_BLOCKMAP_LAYER2 * sizeof(struct hammer_blockmap_layer1))
343 
344 #define HAMMER_BLOCKMAP_LAYER2_OFFSET(zone2_offset)	\
345 	(((zone2_offset) & HAMMER_BLOCKMAP_LAYER2_MASK) /	\
346 	HAMMER_BIGBLOCK_SIZE64 * sizeof(struct hammer_blockmap_layer2))
347 
348 /*
349  * HAMMER UNDO parameters.  The UNDO fifo is mapped directly in the volume
350  * header with an array of layer2 structures.  A maximum of (128x8MB) = 1GB
351  * may be reserved.  The size of the undo fifo is usually set a newfs time
352  * but can be adjusted if the filesystem is taken offline.
353  */
354 #define HAMMER_UNDO_LAYER2	128	/* max layer2 undo mapping entries */
355 
356 /*
357  * All on-disk HAMMER structures which make up elements of the UNDO FIFO
358  * contain a hammer_fifo_head and hammer_fifo_tail structure.  This structure
359  * contains all the information required to validate the fifo element
360  * and to scan the fifo in either direction.  The head is typically embedded
361  * in higher level hammer on-disk structures while the tail is typically
362  * out-of-band.  hdr_size is the size of the whole mess, including the tail.
363  *
364  * All undo structures are guaranteed to not cross a 16K filesystem
365  * buffer boundary.  Most undo structures are fairly small.  Data spaces
366  * are not immediately reused by HAMMER so file data is not usually recorded
367  * as part of an UNDO.
368  *
369  * PAD elements are allowed to take up only 8 bytes of space as a special
370  * case, containing only hdr_signature, hdr_type, and hdr_size fields,
371  * and with the tail overloaded onto the head structure for 8 bytes total.
372  *
373  * Every undo record has a sequence number.  This number is unrelated to
374  * transaction ids and instead collects the undo transactions associated
375  * with a single atomic operation.  A larger transactional operation, such
376  * as a remove(), may consist of several smaller atomic operations
377  * representing raw meta-data operations.
378  *
379  *				HAMMER VERSION 4 CHANGES
380  *
381  * In HAMMER version 4 the undo structure alignment is reduced from 16384
382  * to 512 bytes in order to ensure that each 512 byte sector begins with
383  * a header.  The reserved01 field in the header is now a 32 bit sequence
384  * number.  This allows the recovery code to detect missing sectors
385  * without relying on the 32-bit crc and to definitively identify the current
386  * undo sequence space without having to rely on information from the volume
387  * header.  In addition, new REDO entries in the undo space are used to
388  * record write, write/extend, and transaction id updates.
389  *
390  * The grand result is:
391  *
392  * (1) The volume header no longer needs to be synchronized for most
393  *     flush and fsync operations.
394  *
395  * (2) Most fsync operations need only lay down REDO records
396  *
397  * (3) Data overwrite for nohistory operations covered by REDO records
398  *     can be supported (instead of rolling a new block allocation),
399  *     by rolling UNDO for the prior contents of the data.
400  *
401  *				HAMMER VERSION 5 CHANGES
402  *
403  * Hammer version 5 contains a minor adjustment making layer2's bytes_free
404  * field signed, allowing dedup to push it into the negative domain.
405  */
406 #define HAMMER_HEAD_ONDISK_SIZE		32
407 #define HAMMER_HEAD_ALIGN		8
408 #define HAMMER_HEAD_ALIGN_MASK		(HAMMER_HEAD_ALIGN - 1)
409 #define HAMMER_TAIL_ONDISK_SIZE		8
410 #define HAMMER_HEAD_DOALIGN(bytes)	\
411 	(((bytes) + HAMMER_HEAD_ALIGN_MASK) & ~HAMMER_HEAD_ALIGN_MASK)
412 
413 #define HAMMER_UNDO_ALIGN		512
414 #define HAMMER_UNDO_ALIGN64		((u_int64_t)512)
415 #define HAMMER_UNDO_MASK		(HAMMER_UNDO_ALIGN - 1)
416 #define HAMMER_UNDO_MASK64		(HAMMER_UNDO_ALIGN64 - 1)
417 
418 struct hammer_fifo_head {
419 	u_int16_t hdr_signature;
420 	u_int16_t hdr_type;
421 	u_int32_t hdr_size;	/* Aligned size of the whole mess */
422 	u_int32_t hdr_seq;	/* Sequence number */
423 	hammer_crc_t hdr_crc;	/* XOR crc up to field w/ crc after field */
424 };
425 
426 #define HAMMER_FIFO_HEAD_CRCOFF	offsetof(struct hammer_fifo_head, hdr_crc)
427 
428 struct hammer_fifo_tail {
429 	u_int16_t tail_signature;
430 	u_int16_t tail_type;
431 	u_int32_t tail_size;	/* aligned size of the whole mess */
432 };
433 
434 typedef struct hammer_fifo_head *hammer_fifo_head_t;
435 typedef struct hammer_fifo_tail *hammer_fifo_tail_t;
436 
437 /*
438  * Fifo header types.
439  */
440 #define HAMMER_HEAD_TYPE_PAD	(0x0040U|HAMMER_HEAD_FLAG_FREE)
441 #define HAMMER_HEAD_TYPE_DUMMY	0x0041U		/* dummy entry w/seqno */
442 #define HAMMER_HEAD_TYPE_42	0x0042U
443 #define HAMMER_HEAD_TYPE_UNDO	0x0043U		/* random UNDO information */
444 #define HAMMER_HEAD_TYPE_REDO	0x0044U		/* data REDO / fast fsync */
445 #define HAMMER_HEAD_TYPE_45	0x0045U
446 
447 #define HAMMER_HEAD_FLAG_FREE	0x8000U		/* Indicates object freed */
448 
449 #define HAMMER_HEAD_SIGNATURE	0xC84EU
450 #define HAMMER_TAIL_SIGNATURE	0xC74FU
451 
452 #define HAMMER_HEAD_SEQ_BEG	0x80000000U
453 #define HAMMER_HEAD_SEQ_END	0x40000000U
454 #define HAMMER_HEAD_SEQ_MASK	0x3FFFFFFFU
455 
456 /*
457  * Misc FIFO structures.
458  *
459  * UNDO - Raw meta-data media updates.
460  */
461 struct hammer_fifo_undo {
462 	struct hammer_fifo_head	head;
463 	hammer_off_t		undo_offset;	/* zone-1 offset */
464 	int32_t			undo_data_bytes;
465 	int32_t			undo_reserved01;
466 	/* followed by data */
467 };
468 
469 /*
470  * REDO (HAMMER version 4+) - Logical file writes/truncates.
471  *
472  * REDOs contain information which will be duplicated in a later meta-data
473  * update, allowing fast write()+fsync() operations.  REDOs can be ignored
474  * without harming filesystem integrity but must be processed if fsync()
475  * semantics are desired.
476  *
477  * Unlike UNDOs which are processed backwards within the recovery span,
478  * REDOs must be processed forwards starting further back (starting outside
479  * the recovery span).
480  *
481  *	WRITE	- Write logical file (with payload).  Executed both
482  *		  out-of-span and in-span.  Out-of-span WRITEs may be
483  *		  filtered out by TERMs.
484  *
485  *	TRUNC	- Truncate logical file (no payload).  Executed both
486  *		  out-of-span and in-span.  Out-of-span WRITEs may be
487  *		  filtered out by TERMs.
488  *
489  *	TERM_*	- Indicates meta-data was committed (if out-of-span) or
490  *		  will be rolled-back (in-span).  Any out-of-span TERMs
491  *		  matching earlier WRITEs remove those WRITEs from
492  *		  consideration as they might conflict with a later data
493  *		  commit (which is not being rolled-back).
494  *
495  *	SYNC	- The earliest in-span SYNC (the last one when scanning
496  *		  backwards) tells the recovery code how far out-of-span
497  *		  it must go to run REDOs.
498  *
499  * NOTE: WRITEs do not always have matching TERMs even under
500  *	 perfect conditions because truncations might remove the
501  *	 buffers from consideration.  I/O problems can also remove
502  *	 buffers from consideration.
503  *
504  *	 TRUNCSs do not always have matching TERMs because several
505  *	 truncations may be aggregated together into a single TERM.
506  */
507 struct hammer_fifo_redo {
508 	struct hammer_fifo_head	head;
509 	int64_t			redo_objid;	/* file being written */
510 	hammer_off_t		redo_offset;	/* logical offset in file */
511 	int32_t			redo_data_bytes;
512 	u_int32_t		redo_flags;
513 	u_int32_t		redo_localization;
514 	u_int32_t		redo_reserved;
515 	u_int64_t		redo_mtime;	/* set mtime */
516 };
517 
518 #define HAMMER_REDO_WRITE	0x00000001
519 #define HAMMER_REDO_TRUNC	0x00000002
520 #define HAMMER_REDO_TERM_WRITE	0x00000004
521 #define HAMMER_REDO_TERM_TRUNC	0x00000008
522 #define HAMMER_REDO_SYNC	0x00000010
523 
524 union hammer_fifo_any {
525 	struct hammer_fifo_head	head;
526 	struct hammer_fifo_undo	undo;
527 	struct hammer_fifo_redo	redo;
528 };
529 
530 typedef struct hammer_fifo_redo *hammer_fifo_redo_t;
531 typedef struct hammer_fifo_undo *hammer_fifo_undo_t;
532 typedef union hammer_fifo_any *hammer_fifo_any_t;
533 
534 /*
535  * Volume header types
536  */
537 #define HAMMER_FSBUF_VOLUME	0xC8414D4DC5523031ULL	/* HAMMER01 */
538 #define HAMMER_FSBUF_VOLUME_REV	0x313052C54D4D41C8ULL	/* (reverse endian) */
539 
540 /*
541  * The B-Tree structures need hammer_fsbuf_head.
542  */
543 #include "hammer_btree.h"
544 
545 /*
546  * HAMMER Volume header
547  *
548  * A HAMMER filesystem is built from any number of block devices,  Each block
549  * device contains a volume header followed by however many buffers fit
550  * into the volume.
551  *
552  * One of the volumes making up a HAMMER filesystem is the master, the
553  * rest are slaves.  It does not have to be volume #0.
554  *
555  * The volume header takes up an entire 16K filesystem buffer and may
556  * represent up to 64KTB (65536 TB) of space.
557  *
558  * Special field notes:
559  *
560  *	vol_bot_beg - offset of boot area (mem_beg - bot_beg bytes)
561  *	vol_mem_beg - offset of memory log (clu_beg - mem_beg bytes)
562  *	vol_buf_beg - offset of the first buffer.
563  *
564  *	The memory log area allows a kernel to cache new records and data
565  *	in memory without allocating space in the actual filesystem to hold
566  *	the records and data.  In the event that a filesystem becomes full,
567  *	any records remaining in memory can be flushed to the memory log
568  *	area.  This allows the kernel to immediately return success.
569  */
570 
571 #define HAMMER_BOOT_MINBYTES		(32*1024)
572 #define HAMMER_BOOT_NOMBYTES		(64LL*1024*1024)
573 #define HAMMER_BOOT_MAXBYTES		(256LL*1024*1024)
574 
575 #define HAMMER_MEM_MINBYTES		(256*1024)
576 #define HAMMER_MEM_NOMBYTES		(1LL*1024*1024*1024)
577 #define HAMMER_MEM_MAXBYTES		(64LL*1024*1024*1024)
578 
579 struct hammer_volume_ondisk {
580 	u_int64_t vol_signature;/* Signature */
581 
582 	int64_t vol_bot_beg;	/* byte offset of boot area or 0 */
583 	int64_t vol_mem_beg;	/* byte offset of memory log or 0 */
584 	int64_t vol_buf_beg;	/* byte offset of first buffer in volume */
585 	int64_t vol_buf_end;	/* byte offset of volume EOF (on buf bndry) */
586 	int64_t vol_locked;	/* reserved clusters are >= this offset */
587 
588 	uuid_t    vol_fsid;	/* identify filesystem */
589 	uuid_t    vol_fstype;	/* identify filesystem type */
590 	char	  vol_name[64];	/* Name of volume */
591 
592 	int32_t vol_no;		/* volume number within filesystem */
593 	int32_t vol_count;	/* number of volumes making up FS */
594 
595 	u_int32_t vol_version;	/* version control information */
596 	hammer_crc_t vol_crc;	/* header crc */
597 	u_int32_t vol_flags;	/* volume flags */
598 	u_int32_t vol_rootvol;	/* which volume is the root volume? */
599 
600 	int32_t vol_reserved04;
601 	int32_t vol_reserved05;
602 	u_int32_t vol_reserved06;
603 	u_int32_t vol_reserved07;
604 
605 	int32_t vol_blocksize;		/* for statfs only */
606 	int32_t vol_reserved08;
607 	int64_t vol_nblocks;		/* total allocatable hammer bufs */
608 
609 	/*
610 	 * These fields are initialized and space is reserved in every
611 	 * volume making up a HAMMER filesytem, but only the master volume
612 	 * contains valid data.
613 	 */
614 	int64_t vol0_stat_bigblocks;	/* total bigblocks when fs is empty */
615 	int64_t vol0_stat_freebigblocks;/* number of free bigblocks */
616 	int64_t	vol0_stat_bytes;	/* for statfs only */
617 	int64_t vol0_stat_inodes;	/* for statfs only */
618 	int64_t vol0_stat_records;	/* total records in filesystem */
619 	hammer_off_t vol0_btree_root;	/* B-Tree root */
620 	hammer_tid_t vol0_next_tid;	/* highest partially synchronized TID */
621 	hammer_off_t vol0_unused03;
622 
623 	/*
624 	 * Blockmaps for zones.  Not all zones use a blockmap.  Note that
625 	 * the entire root blockmap is cached in the hammer_mount structure.
626 	 */
627 	struct hammer_blockmap	vol0_blockmap[HAMMER_MAX_ZONES];
628 
629 	/*
630 	 * Array of zone-2 addresses for undo FIFO.
631 	 */
632 	hammer_off_t		vol0_undo_array[HAMMER_UNDO_LAYER2];
633 
634 };
635 
636 typedef struct hammer_volume_ondisk *hammer_volume_ondisk_t;
637 
638 #define HAMMER_VOLF_VALID		0x0001	/* valid entry */
639 #define HAMMER_VOLF_OPEN		0x0002	/* volume is open */
640 #define HAMMER_VOLF_NEEDFLUSH		0x0004	/* volume needs flush */
641 
642 #define HAMMER_VOL_CRCSIZE1	\
643 	offsetof(struct hammer_volume_ondisk, vol_crc)
644 #define HAMMER_VOL_CRCSIZE2	\
645 	(sizeof(struct hammer_volume_ondisk) - HAMMER_VOL_CRCSIZE1 -	\
646 	 sizeof(hammer_crc_t))
647 
648 #define HAMMER_VOL_VERSION_MIN		1	/* minimum supported version */
649 #define HAMMER_VOL_VERSION_DEFAULT	6	/* newfs default version */
650 #define HAMMER_VOL_VERSION_WIP		7	/* version >= this is WIP */
651 #define HAMMER_VOL_VERSION_MAX		6	/* maximum supported version */
652 
653 #define HAMMER_VOL_VERSION_ONE		1
654 #define HAMMER_VOL_VERSION_TWO		2	/* new dirent layout (2.3+) */
655 #define HAMMER_VOL_VERSION_THREE	3	/* new snapshot layout (2.5+) */
656 #define HAMMER_VOL_VERSION_FOUR		4	/* new undo/flush (2.5+) */
657 #define HAMMER_VOL_VERSION_FIVE		5	/* dedup (2.9+) */
658 #define HAMMER_VOL_VERSION_SIX		6	/* DIRHASH_ALG1 */
659 
660 /*
661  * Record types are fairly straightforward.  The B-Tree includes the record
662  * type in its index sort.
663  */
664 #define HAMMER_RECTYPE_UNKNOWN		0
665 #define HAMMER_RECTYPE_LOWEST		1	/* lowest record type avail */
666 #define HAMMER_RECTYPE_INODE		1	/* inode in obj_id space */
667 #define HAMMER_RECTYPE_UNUSED02		2
668 #define HAMMER_RECTYPE_UNUSED03		3
669 #define HAMMER_RECTYPE_DATA		0x0010
670 #define HAMMER_RECTYPE_DIRENTRY		0x0011
671 #define HAMMER_RECTYPE_DB		0x0012
672 #define HAMMER_RECTYPE_EXT		0x0013	/* ext attributes */
673 #define HAMMER_RECTYPE_FIX		0x0014	/* fixed attribute */
674 #define HAMMER_RECTYPE_PFS		0x0015	/* PFS management */
675 #define HAMMER_RECTYPE_SNAPSHOT		0x0016	/* Snapshot management */
676 #define HAMMER_RECTYPE_CONFIG		0x0017	/* hammer cleanup config */
677 #define HAMMER_RECTYPE_MOVED		0x8000	/* special recovery flag */
678 #define HAMMER_RECTYPE_MAX		0xFFFF
679 
680 #define HAMMER_RECTYPE_ENTRY_START	(HAMMER_RECTYPE_INODE + 1)
681 #define HAMMER_RECTYPE_CLEAN_START	HAMMER_RECTYPE_EXT
682 
683 #define HAMMER_FIXKEY_SYMLINK		1
684 
685 #define HAMMER_OBJTYPE_UNKNOWN		0	/* never exists on-disk as unknown */
686 #define HAMMER_OBJTYPE_DIRECTORY	1
687 #define HAMMER_OBJTYPE_REGFILE		2
688 #define HAMMER_OBJTYPE_DBFILE		3
689 #define HAMMER_OBJTYPE_FIFO		4
690 #define HAMMER_OBJTYPE_CDEV		5
691 #define HAMMER_OBJTYPE_BDEV		6
692 #define HAMMER_OBJTYPE_SOFTLINK		7
693 #define HAMMER_OBJTYPE_PSEUDOFS		8	/* pseudo filesystem obj */
694 #define HAMMER_OBJTYPE_SOCKET		9
695 
696 /*
697  * HAMMER inode attribute data
698  *
699  * The data reference for a HAMMER inode points to this structure.  Any
700  * modifications to the contents of this structure will result in a
701  * replacement operation.
702  *
703  * parent_obj_id is only valid for directories (which cannot be hard-linked),
704  * and specifies the parent directory obj_id.  This field will also be set
705  * for non-directory inodes as a recovery aid, but can wind up holding
706  * stale information.  However, since object id's are not reused, the worse
707  * that happens is that the recovery code is unable to use it.
708  *
709  * NOTE: Future note on directory hardlinks.  We can implement a record type
710  * which allows us to point to multiple parent directories.
711  */
712 struct hammer_inode_data {
713 	u_int16_t version;	/* inode data version */
714 	u_int16_t mode;		/* basic unix permissions */
715 	u_int32_t uflags;	/* chflags */
716 	u_int32_t rmajor;	/* used by device nodes */
717 	u_int32_t rminor;	/* used by device nodes */
718 	u_int64_t ctime;
719 	int64_t parent_obj_id;	/* parent directory obj_id */
720 	uuid_t	  uid;
721 	uuid_t	  gid;
722 
723 	u_int8_t  obj_type;
724 	u_int8_t  cap_flags;	/* capability support flags (extension) */
725 	u_int16_t reserved02;
726 	u_int32_t reserved03;	/* RESERVED FOR POSSIBLE FUTURE BIRTHTIME */
727 	u_int64_t nlinks;	/* hard links */
728 	u_int64_t size;		/* filesystem object size */
729 	union {
730 		struct {
731 			char	reserved06[16];
732 			u_int32_t parent_obj_localization;
733 			u_int32_t integrity_crc;
734 		} obj;
735 		char	symlink[24];	/* HAMMER_INODE_BASESYMLEN */
736 	} ext;
737 	u_int64_t mtime;	/* mtime must be second-to-last */
738 	u_int64_t atime;	/* atime must be last */
739 };
740 
741 /*
742  * Neither mtime nor atime upates are CRCd by the B-Tree element.
743  * mtime updates have UNDO, atime updates do not.
744  */
745 #define HAMMER_ITIMES_BASE(ino_data)	(&(ino_data)->mtime)
746 #define HAMMER_ITIMES_BYTES		(sizeof(u_int64_t) * 2)
747 
748 #define HAMMER_INODE_CRCSIZE	\
749 	offsetof(struct hammer_inode_data, mtime)
750 
751 #define HAMMER_INODE_DATA_VERSION	1
752 #define HAMMER_OBJID_ROOT		1
753 #define HAMMER_INODE_BASESYMLEN		24	/* see ext.symlink */
754 
755 /*
756  * Capability & implementation flags.
757  *
758  * DIR_LOCAL_INO - Use inode B-Tree localization for directory entries.
759  */
760 #define HAMMER_INODE_CAP_DIRHASH_MASK	0x03	/* directory: hash algorithm */
761 #define HAMMER_INODE_CAP_DIRHASH_ALG0	0x00
762 #define HAMMER_INODE_CAP_DIRHASH_ALG1	0x01
763 #define HAMMER_INODE_CAP_DIRHASH_ALG2	0x02
764 #define HAMMER_INODE_CAP_DIRHASH_ALG3	0x03
765 #define HAMMER_INODE_CAP_DIR_LOCAL_INO	0x04	/* use inode localization */
766 
767 /*
768  * A HAMMER directory entry associates a HAMMER filesystem object with a
769  * namespace.  It is possible to hook into a pseudo-filesystem (with its
770  * own inode numbering space) in the filesystem by setting the high
771  * 16 bits of the localization field.  The low 16 bits must be 0 and
772  * are reserved for future use.
773  *
774  * Directory entries are indexed with a 128 bit namekey rather then an
775  * offset.  A portion of the namekey is an iterator/randomizer to deal
776  * with collisions.
777  *
778  * NOTE: base.base.obj_type from the related B-Tree leaf entry holds
779  * the filesystem object type of obj_id, e.g. a den_type equivalent.
780  * It is not stored in hammer_entry_data.
781  *
782  * NOTE: den_name / the filename data reference is NOT terminated with \0.
783  */
784 struct hammer_entry_data {
785 	int64_t obj_id;			/* object being referenced */
786 	u_int32_t localization;		/* identify pseudo-filesystem */
787 	u_int32_t reserved02;
788 	char	name[16];		/* name (extended) */
789 };
790 
791 #define HAMMER_ENTRY_NAME_OFF	offsetof(struct hammer_entry_data, name[0])
792 #define HAMMER_ENTRY_SIZE(nlen)	offsetof(struct hammer_entry_data, name[nlen])
793 
794 /*
795  * Symlink data which does not fit in the inode is stored in a separte
796  * FIX type record.
797  */
798 struct hammer_symlink_data {
799 	char	name[16];
800 };
801 
802 #define HAMMER_SYMLINK_NAME_OFF	offsetof(struct hammer_symlink_data, name[0])
803 
804 /*
805  * The root inode for the primary filesystem and root inode for any
806  * pseudo-fs may be tagged with an optional data structure using
807  * HAMMER_RECTYPE_PFS and localization id.  This structure allows
808  * the node to be used as a mirroring master or slave.
809  *
810  * When operating as a slave CD's into the node automatically become read-only
811  * and as-of sync_end_tid.
812  *
813  * When operating as a master the read PFSD info sets sync_end_tid to
814  * the most recently flushed TID.
815  *
816  * sync_low_tid is not yet used but will represent the highest pruning
817  * end-point, after which full history is available.
818  *
819  * We need to pack this structure making it equally sized on both 32-bit and
820  * 64-bit machines as it is part of struct hammer_ioc_mrecord_pfs which is
821  * send over the wire in hammer mirror operations. Only on 64-bit machines
822  * the size of this struct differ when packed or not. This leads us to the
823  * situation where old 64-bit systems (using the non-packed structure),
824  * which were never able to mirror to/from 32-bit systems, are now no longer
825  * able to mirror to/from newer 64-bit systems (using the packed structure).
826  */
827 struct hammer_pseudofs_data {
828 	hammer_tid_t	sync_low_tid;	/* full history beyond this point */
829 	hammer_tid_t	sync_beg_tid;	/* earliest tid w/ full history avail */
830 	hammer_tid_t	sync_end_tid;	/* current synchronizatoin point */
831 	u_int64_t	sync_beg_ts;	/* real-time of last completed sync */
832 	u_int64_t	sync_end_ts;	/* initiation of current sync cycle */
833 	uuid_t		shared_uuid;	/* shared uuid (match required) */
834 	uuid_t		unique_uuid;	/* unique uuid of this master/slave */
835 	int32_t		reserved01;	/* reserved for future master_id */
836 	int32_t		mirror_flags;	/* misc flags */
837 	char		label[64];	/* filesystem space label */
838 	char		snapshots[64];	/* softlink dir for pruning */
839 	int16_t		prune_time;	/* how long to spend pruning */
840 	int16_t		prune_freq;	/* how often we prune */
841 	int16_t		reblock_time;	/* how long to spend reblocking */
842 	int16_t		reblock_freq;	/* how often we reblock */
843 	int32_t		snapshot_freq;	/* how often we create a snapshot */
844 	int32_t		prune_min;	/* do not prune recent history */
845 	int32_t		prune_max;	/* do not retain history beyond here */
846 	int32_t		reserved[16];
847 } __packed;
848 
849 typedef struct hammer_pseudofs_data *hammer_pseudofs_data_t;
850 
851 #define HAMMER_PFSD_SLAVE	0x00000001
852 #define HAMMER_PFSD_DELETED	0x80000000
853 
854 /*
855  * Snapshot meta-data { Objid = HAMMER_OBJID_ROOT, Key = tid, rectype = SNAPSHOT }.
856  *
857  * Snapshot records replace the old <fs>/snapshots/<softlink> methodology.  Snapshot
858  * records are mirrored but may be independantly managed once they are laid down on
859  * a slave.
860  *
861  * NOTE: The b-tree key is signed, the tid is not, so callers must still sort the
862  *	 results.
863  *
864  * NOTE: Reserved fields must be zero (as usual)
865  */
866 struct hammer_snapshot_data {
867 	hammer_tid_t	tid;		/* the snapshot TID itself (== key) */
868 	u_int64_t	ts;		/* real-time when snapshot was made */
869 	u_int64_t	reserved01;
870 	u_int64_t	reserved02;
871 	char		label[64];	/* user-supplied description */
872 	u_int64_t	reserved03[4];
873 };
874 
875 /*
876  * Config meta-data { ObjId = HAMMER_OBJID_ROOT, Key = 0, rectype = CONFIG }.
877  *
878  * Used to store the hammer cleanup config.  This data is not mirrored.
879  */
880 struct hammer_config_data {
881 	char		text[1024];
882 };
883 
884 /*
885  * Rollup various structures embedded as record data
886  */
887 union hammer_data_ondisk {
888 	struct hammer_entry_data entry;
889 	struct hammer_inode_data inode;
890 	struct hammer_symlink_data symlink;
891 	struct hammer_pseudofs_data pfsd;
892 	struct hammer_snapshot_data snap;
893 	struct hammer_config_data config;
894 };
895 
896 typedef union hammer_data_ondisk *hammer_data_ondisk_t;
897 
898 #endif
899