1/*-
2 * Copyright (c) 2011-2018 The DragonFly Project.  All rights reserved.
3 *
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@dragonflybsd.org>
6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in
16 *    the documentation and/or other materials provided with the
17 *    distribution.
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 *    contributors may be used to endorse or promote products derived
20 *    from this software without specific, prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#ifndef _HAMMER2_DISK_H_
37#define _HAMMER2_DISK_H_
38
39#ifndef _SYS_UUID_H_
40#include <sys/uuid.h>
41#endif
42#ifndef _SYS_DMSG_H_
43/*
44 * dmsg_hdr must be 64 bytes
45 */
46struct dmsg_hdr {
47	uint16_t	magic;		/* 00 sanity, synchro, endian */
48	uint16_t	reserved02;	/* 02 */
49	uint32_t	salt;		/* 04 random salt helps w/crypto */
50
51	uint64_t	msgid;		/* 08 message transaction id */
52	uint64_t	circuit;	/* 10 circuit id or 0	*/
53	uint64_t	reserved18;	/* 18 */
54
55	uint32_t	cmd;		/* 20 flags | cmd | hdr_size / ALIGN */
56	uint32_t	aux_crc;	/* 24 auxiliary data crc */
57	uint32_t	aux_bytes;	/* 28 auxiliary data length (bytes) */
58	uint32_t	error;		/* 2C error code or 0 */
59	uint64_t	aux_descr;	/* 30 negotiated OOB data descr */
60	uint32_t	reserved38;	/* 38 */
61	uint32_t	hdr_crc;	/* 3C (aligned) extended header crc */
62};
63
64typedef struct dmsg_hdr dmsg_hdr_t;
65#endif
66
67/*
68 * The structures below represent the on-disk media structures for the HAMMER2
69 * filesystem.  Note that all fields for on-disk structures are naturally
70 * aligned.  The host endian format is typically used - compatibility is
71 * possible if the implementation detects reversed endian and adjusts accesses
72 * accordingly.
73 *
74 * HAMMER2 primarily revolves around the directory topology:  inodes,
75 * directory entries, and block tables.  Block device buffer cache buffers
76 * are always 64KB.  Logical file buffers are typically 16KB.  All data
77 * references utilize 64-bit byte offsets.
78 *
79 * Free block management is handled independently using blocks reserved by
80 * the media topology.
81 */
82
83/*
84 * The data at the end of a file or directory may be a fragment in order
85 * to optimize storage efficiency.  The minimum fragment size is 1KB.
86 * Since allocations are in powers of 2 fragments must also be sized in
87 * powers of 2 (1024, 2048, ... 65536).
88 *
89 * For the moment the maximum allocation size is HAMMER2_PBUFSIZE (64K),
90 * which is 2^16.  Larger extents may be supported in the future.  Smaller
91 * fragments might be supported in the future (down to 64 bytes is possible),
92 * but probably will not be.
93 *
94 * A full indirect block use supports 512 x 128-byte blockrefs in a 64KB
95 * buffer.  Indirect blocks down to 1KB are supported to keep small
96 * directories small.
97 *
98 * A maximally sized file (2^64-1 bytes) requires ~6 indirect block levels
99 * using 64KB indirect blocks (128 byte refs, 512 or radix 9 per indblk).
100 *
101 *	16(datablk) + 9 + 9 + 9 + 9 + 9 + 9 = ~70.
102 *	16(datablk) + 7 + 9 + 9 + 9 + 9 + 9 = ~68.  (smaller top level indblk)
103 *
104 * The actual depth depends on copies redundancy and whether the filesystem
105 * has chosen to use a smaller indirect block size at the top level or not.
106 */
107#define HAMMER2_ALLOC_MIN	1024	/* minimum allocation size */
108#define HAMMER2_RADIX_MIN	10	/* minimum allocation size 2^N */
109#define HAMMER2_ALLOC_MAX	65536	/* maximum allocation size */
110#define HAMMER2_RADIX_MAX	16	/* maximum allocation size 2^N */
111#define HAMMER2_RADIX_KEY	64	/* number of bits in key */
112
113/*
114 * MINALLOCSIZE		- The minimum allocation size.  This can be smaller
115 *		  	  or larger than the minimum physical IO size.
116 *
117 *			  NOTE: Should not be larger than 1K since inodes
118 *				are 1K.
119 *
120 * MINIOSIZE		- The minimum IO size.  This must be less than
121 *			  or equal to HAMMER2_LBUFSIZE.
122 *
123 * HAMMER2_LBUFSIZE	- Nominal buffer size for I/O rollups.
124 *
125 * HAMMER2_PBUFSIZE	- Topological block size used by files for all
126 *			  blocks except the block straddling EOF.
127 *
128 * HAMMER2_SEGSIZE	- Allocation map segment size, typically 4MB
129 *			  (space represented by a level0 bitmap).
130 */
131
132#define HAMMER2_SEGSIZE		(1 << HAMMER2_FREEMAP_LEVEL0_RADIX)
133#define HAMMER2_SEGRADIX	HAMMER2_FREEMAP_LEVEL0_RADIX
134
135#define HAMMER2_PBUFRADIX	16	/* physical buf (1<<16) bytes */
136#define HAMMER2_PBUFSIZE	65536
137#define HAMMER2_LBUFRADIX	14	/* logical buf (1<<14) bytes */
138#define HAMMER2_LBUFSIZE	16384
139
140/*
141 * Generally speaking we want to use 16K and 64K I/Os
142 */
143#define HAMMER2_MINIORADIX	HAMMER2_LBUFRADIX
144#define HAMMER2_MINIOSIZE	HAMMER2_LBUFSIZE
145
146#define HAMMER2_IND_BYTES_MIN	4096
147#define HAMMER2_IND_BYTES_NOM	HAMMER2_LBUFSIZE
148#define HAMMER2_IND_BYTES_MAX	HAMMER2_PBUFSIZE
149#define HAMMER2_IND_RADIX_MIN	12
150#define HAMMER2_IND_RADIX_NOM	HAMMER2_LBUFRADIX
151#define HAMMER2_IND_RADIX_MAX	HAMMER2_PBUFRADIX
152#define HAMMER2_IND_COUNT_MIN	(HAMMER2_IND_BYTES_MIN / \
153				 sizeof(hammer2_blockref_t))
154#define HAMMER2_IND_COUNT_MAX	(HAMMER2_IND_BYTES_MAX / \
155				 sizeof(hammer2_blockref_t))
156
157/*
158 * In HAMMER2, arrays of blockrefs are fully set-associative, meaning that
159 * any element can occur at any index and holes can be anywhere.  As a
160 * future optimization we will be able to flag that such arrays are sorted
161 * and thus optimize lookups, but for now we don't.
162 *
163 * Inodes embed either 512 bytes of direct data or an array of 4 blockrefs,
164 * resulting in highly efficient storage for files <= 512 bytes and for files
165 * <= 512KB.  Up to 4 directory entries can be referenced from a directory
166 * without requiring an indirect block.
167 *
168 * Indirect blocks are typically either 4KB (64 blockrefs / ~4MB represented),
169 * or 64KB (1024 blockrefs / ~64MB represented).
170 */
171#define HAMMER2_SET_RADIX		2	/* radix 2 = 4 entries */
172#define HAMMER2_SET_COUNT		(1 << HAMMER2_SET_RADIX)
173#define HAMMER2_EMBEDDED_BYTES		512	/* inode blockset/dd size */
174#define HAMMER2_EMBEDDED_RADIX		9
175
176#define HAMMER2_PBUFMASK	(HAMMER2_PBUFSIZE - 1)
177#define HAMMER2_LBUFMASK	(HAMMER2_LBUFSIZE - 1)
178#define HAMMER2_SEGMASK		(HAMMER2_SEGSIZE - 1)
179
180#define HAMMER2_LBUFMASK64	((hammer2_off_t)HAMMER2_LBUFMASK)
181#define HAMMER2_PBUFSIZE64	((hammer2_off_t)HAMMER2_PBUFSIZE)
182#define HAMMER2_PBUFMASK64	((hammer2_off_t)HAMMER2_PBUFMASK)
183#define HAMMER2_SEGSIZE64	((hammer2_off_t)HAMMER2_SEGSIZE)
184#define HAMMER2_SEGMASK64	((hammer2_off_t)HAMMER2_SEGMASK)
185
186#define HAMMER2_UUID_STRING	"5cbb9ad1-862d-11dc-a94d-01301bb8a9f5"
187
188/*
189 * A 4MB segment is reserved at the beginning of each 2GB zone.  This segment
190 * contains the volume header (or backup volume header), the free block
191 * table, and possibly other information in the future.  A 4MB segment for
192 * freemap is reserved at the beginning of every 1GB.
193 *
194 * 4MB = 64 x 64K blocks.  Each 4MB segment is broken down as follows:
195 *
196 * ==========
197 *  0 volume header (for the first four 2GB zones)
198 *  1 freemap00 level1 FREEMAP_LEAF (256 x 128B bitmap data per 1GB)
199 *  2           level2 FREEMAP_NODE (256 x 128B indirect block per 256GB)
200 *  3           level3 FREEMAP_NODE (256 x 128B indirect block per 64TB)
201 *  4           level4 FREEMAP_NODE (256 x 128B indirect block per 16PB)
202 *  5           level5 FREEMAP_NODE (256 x 128B indirect block per 4EB)
203 *  6 freemap01 level1 (rotation)
204 *  7           level2
205 *  8           level3
206 *  9           level4
207 * 10           level5
208 * 11 freemap02 level1 (rotation)
209 * 12           level2
210 * 13           level3
211 * 14           level4
212 * 15           level5
213 * 16 freemap03 level1 (rotation)
214 * 17           level2
215 * 18           level3
216 * 19           level4
217 * 20           level5
218 * 21 freemap04 level1 (rotation)
219 * 22           level2
220 * 23           level3
221 * 24           level4
222 * 25           level5
223 * 26 freemap05 level1 (rotation)
224 * 27           level2
225 * 28           level3
226 * 29           level4
227 * 30           level5
228 * 31 freemap06 level1 (rotation)
229 * 32           level2
230 * 33           level3
231 * 34           level4
232 * 35           level5
233 * 36 freemap07 level1 (rotation)
234 * 37           level2
235 * 38           level3
236 * 39           level4
237 * 40           level5
238 * 41 unused
239 * .. unused
240 * 63 unused
241 * ==========
242 *
243 * The first four 2GB zones contain volume headers and volume header backups.
244 * After that the volume header block# is reserved for future use.  Similarly,
245 * there are many blocks related to various Freemap levels which are not
246 * used in every segment and those are also reserved for future use.
247 * Note that each FREEMAP_LEAF or FREEMAP_NODE uses 32KB out of 64KB slot.
248 *
249 *			Freemap (see the FREEMAP document)
250 *
251 * The freemap utilizes blocks #1-40 in 8 sets of 5 blocks.  Each block in
252 * a set represents a level of depth in the freemap topology.  Eight sets
253 * exist to prevent live updates from disturbing the state of the freemap
254 * were a crash/reboot to occur.  That is, a live update is not committed
255 * until the update's flush reaches the volume root.  There are FOUR volume
256 * roots representing the last four synchronization points, so the freemap
257 * must be consistent no matter which volume root is chosen by the mount
258 * code.
259 *
260 * Each freemap set is 5 x 64K blocks and represents the 1GB, 256GB, 64TB,
261 * 16PB and 4EB indirect map.  The volume header itself has a set of 4 freemap
262 * blockrefs representing another 2 bits, giving us a total 64 bits of
263 * representable address space.
264 *
265 * The Level 0 64KB block represents 1GB of storage represented by 32KB
266 * (256 x struct hammer2_bmap_data).  Each structure represents 4MB of storage
267 * and has a 512 bit bitmap, using 2 bits to represent a 16KB chunk of
268 * storage.  These 2 bits represent the following states:
269 *
270 *	00	Free
271 *	01	(reserved) (Possibly partially allocated)
272 *	10	Possibly free
273 *	11	Allocated
274 *
275 * One important thing to note here is that the freemap resolution is 16KB,
276 * but the minimum storage allocation size is 1KB.  The hammer2 vfs keeps
277 * track of sub-allocations in memory, which means that on a unmount or reboot
278 * the entire 16KB of a partially allocated block will be considered fully
279 * allocated.  It is possible for fragmentation to build up over time, but
280 * defragmentation is fairly easy to accomplish since all modifications
281 * allocate a new block.
282 *
283 * The Second thing to note is that due to the way snapshots and inode
284 * replication works, deleting a file cannot immediately free the related
285 * space.  Furthermore, deletions often do not bother to traverse the
286 * block subhierarchy being deleted.  And to go even further, whole
287 * sub-directory trees can be deleted simply by deleting the directory inode
288 * at the top.  So even though we have a symbol to represent a 'possibly free'
289 * block (binary 10), only the bulk free scanning code can actually use it.
290 * Normal 'rm's or other deletions do not.
291 *
292 * WARNING!  ZONE_SEG and VOLUME_ALIGN must be a multiple of 1<<LEVEL0_RADIX
293 *	     (i.e. a multiple of 4MB).  VOLUME_ALIGN must be >= ZONE_SEG.
294 *
295 * In Summary:
296 *
297 * (1) Modifications to freemap blocks 'allocate' a new copy (aka use a block
298 *     from the next set).  The new copy is reused until a flush occurs at
299 *     which point the next modification will then rotate to the next set.
300 */
301#define HAMMER2_VOLUME_ALIGN		(8 * 1024 * 1024)
302#define HAMMER2_VOLUME_ALIGN64		((hammer2_off_t)HAMMER2_VOLUME_ALIGN)
303#define HAMMER2_VOLUME_ALIGNMASK	(HAMMER2_VOLUME_ALIGN - 1)
304#define HAMMER2_VOLUME_ALIGNMASK64     ((hammer2_off_t)HAMMER2_VOLUME_ALIGNMASK)
305
306#define HAMMER2_NEWFS_ALIGN		(HAMMER2_VOLUME_ALIGN)
307#define HAMMER2_NEWFS_ALIGN64		((hammer2_off_t)HAMMER2_VOLUME_ALIGN)
308#define HAMMER2_NEWFS_ALIGNMASK		(HAMMER2_VOLUME_ALIGN - 1)
309#define HAMMER2_NEWFS_ALIGNMASK64	((hammer2_off_t)HAMMER2_NEWFS_ALIGNMASK)
310
311#define HAMMER2_ZONE_BYTES64		(2LLU * 1024 * 1024 * 1024)
312#define HAMMER2_ZONE_MASK64		(HAMMER2_ZONE_BYTES64 - 1)
313#define HAMMER2_ZONE_SEG		(4 * 1024 * 1024)
314#define HAMMER2_ZONE_SEG64		((hammer2_off_t)HAMMER2_ZONE_SEG)
315#define HAMMER2_ZONE_BLOCKS_SEG		(HAMMER2_ZONE_SEG / HAMMER2_PBUFSIZE)
316
317#define HAMMER2_ZONE_FREEMAP_INC	5	/* 5 deep */
318
319#define HAMMER2_ZONE_VOLHDR		0	/* volume header or backup */
320#define HAMMER2_ZONE_FREEMAP_00		1	/* normal freemap rotation */
321#define HAMMER2_ZONE_FREEMAP_01		6	/* normal freemap rotation */
322#define HAMMER2_ZONE_FREEMAP_02		11	/* normal freemap rotation */
323#define HAMMER2_ZONE_FREEMAP_03		16	/* normal freemap rotation */
324#define HAMMER2_ZONE_FREEMAP_04		21	/* normal freemap rotation */
325#define HAMMER2_ZONE_FREEMAP_05		26	/* normal freemap rotation */
326#define HAMMER2_ZONE_FREEMAP_06		31	/* normal freemap rotation */
327#define HAMMER2_ZONE_FREEMAP_07		36	/* normal freemap rotation */
328#define HAMMER2_ZONE_FREEMAP_END	41	/* (non-inclusive) */
329
330#define HAMMER2_ZONE_UNUSED41		41
331#define HAMMER2_ZONE_UNUSED42		42
332#define HAMMER2_ZONE_UNUSED43		43
333#define HAMMER2_ZONE_UNUSED44		44
334#define HAMMER2_ZONE_UNUSED45		45
335#define HAMMER2_ZONE_UNUSED46		46
336#define HAMMER2_ZONE_UNUSED47		47
337#define HAMMER2_ZONE_UNUSED48		48
338#define HAMMER2_ZONE_UNUSED49		49
339#define HAMMER2_ZONE_UNUSED50		50
340#define HAMMER2_ZONE_UNUSED51		51
341#define HAMMER2_ZONE_UNUSED52		52
342#define HAMMER2_ZONE_UNUSED53		53
343#define HAMMER2_ZONE_UNUSED54		54
344#define HAMMER2_ZONE_UNUSED55		55
345#define HAMMER2_ZONE_UNUSED56		56
346#define HAMMER2_ZONE_UNUSED57		57
347#define HAMMER2_ZONE_UNUSED58		58
348#define HAMMER2_ZONE_UNUSED59		59
349#define HAMMER2_ZONE_UNUSED60		60
350#define HAMMER2_ZONE_UNUSED61		61
351#define HAMMER2_ZONE_UNUSED62		62
352#define HAMMER2_ZONE_UNUSED63		63
353#define HAMMER2_ZONE_END		64	/* non-inclusive */
354
355#define HAMMER2_NFREEMAPS		8	/* FREEMAP_00 - FREEMAP_07 */
356
357						/* relative to FREEMAP_x */
358#define HAMMER2_ZONEFM_LEVEL1		0	/* 1GB leafmap */
359#define HAMMER2_ZONEFM_LEVEL2		1	/* 256GB indmap */
360#define HAMMER2_ZONEFM_LEVEL3		2	/* 64TB indmap */
361#define HAMMER2_ZONEFM_LEVEL4		3	/* 16PB indmap */
362#define HAMMER2_ZONEFM_LEVEL5		4	/* 4EB indmap */
363/* LEVEL6 is a set of 4 blockrefs in the volume header 16EB */
364
365/*
366 * Freemap radix.  Assumes a set-count of 4, 128-byte blockrefs,
367 * 32KB indirect block for freemap (LEVELN_PSIZE below).
368 *
369 * Leaf entry represents 4MB of storage broken down into a 512-bit
370 * bitmap, 2-bits per entry.  So course bitmap item represents 16KB.
371 */
372#if HAMMER2_SET_COUNT != 4
373#error "hammer2_disk.h - freemap assumes SET_COUNT is 4"
374#endif
375#define HAMMER2_FREEMAP_LEVEL6_RADIX	64	/* 16EB (end) */
376#define HAMMER2_FREEMAP_LEVEL5_RADIX	62	/* 4EB */
377#define HAMMER2_FREEMAP_LEVEL4_RADIX	54	/* 16PB */
378#define HAMMER2_FREEMAP_LEVEL3_RADIX	46	/* 64TB */
379#define HAMMER2_FREEMAP_LEVEL2_RADIX	38	/* 256GB */
380#define HAMMER2_FREEMAP_LEVEL1_RADIX	30	/* 1GB */
381#define HAMMER2_FREEMAP_LEVEL0_RADIX	22	/* 4MB (128by in l-1 leaf) */
382
383#define HAMMER2_FREEMAP_LEVELN_PSIZE	32768	/* physical bytes */
384
385#define HAMMER2_FREEMAP_LEVEL5_SIZE	((hammer2_off_t)1 <<		\
386					 HAMMER2_FREEMAP_LEVEL5_RADIX)
387#define HAMMER2_FREEMAP_LEVEL4_SIZE	((hammer2_off_t)1 <<		\
388					 HAMMER2_FREEMAP_LEVEL4_RADIX)
389#define HAMMER2_FREEMAP_LEVEL3_SIZE	((hammer2_off_t)1 <<		\
390					 HAMMER2_FREEMAP_LEVEL3_RADIX)
391#define HAMMER2_FREEMAP_LEVEL2_SIZE	((hammer2_off_t)1 <<		\
392					 HAMMER2_FREEMAP_LEVEL2_RADIX)
393#define HAMMER2_FREEMAP_LEVEL1_SIZE	((hammer2_off_t)1 <<		\
394					 HAMMER2_FREEMAP_LEVEL1_RADIX)
395#define HAMMER2_FREEMAP_LEVEL0_SIZE	((hammer2_off_t)1 <<		\
396					 HAMMER2_FREEMAP_LEVEL0_RADIX)
397
398#define HAMMER2_FREEMAP_LEVEL5_MASK	(HAMMER2_FREEMAP_LEVEL5_SIZE - 1)
399#define HAMMER2_FREEMAP_LEVEL4_MASK	(HAMMER2_FREEMAP_LEVEL4_SIZE - 1)
400#define HAMMER2_FREEMAP_LEVEL3_MASK	(HAMMER2_FREEMAP_LEVEL3_SIZE - 1)
401#define HAMMER2_FREEMAP_LEVEL2_MASK	(HAMMER2_FREEMAP_LEVEL2_SIZE - 1)
402#define HAMMER2_FREEMAP_LEVEL1_MASK	(HAMMER2_FREEMAP_LEVEL1_SIZE - 1)
403#define HAMMER2_FREEMAP_LEVEL0_MASK	(HAMMER2_FREEMAP_LEVEL0_SIZE - 1)
404
405#define HAMMER2_FREEMAP_COUNT		(int)(HAMMER2_FREEMAP_LEVELN_PSIZE / \
406					 sizeof(hammer2_bmap_data_t))
407
408/*
409 * XXX I made a mistake and made the reserved area begin at each LEVEL1 zone,
410 *     which is on a 1GB demark.  This will eat a little more space but for
411 *     now we retain compatibility and make FMZONEBASE every 1GB
412 */
413#define H2FMZONEBASE(key)	((key) & ~HAMMER2_FREEMAP_LEVEL1_MASK)
414#define H2FMBASE(key, radix)	((key) & ~(((hammer2_off_t)1 << (radix)) - 1))
415
416/*
417 * 16KB bitmap granularity (x2 bits per entry).
418 */
419#define HAMMER2_FREEMAP_BLOCK_RADIX	14
420#define HAMMER2_FREEMAP_BLOCK_SIZE	(1 << HAMMER2_FREEMAP_BLOCK_RADIX)
421#define HAMMER2_FREEMAP_BLOCK_MASK	(HAMMER2_FREEMAP_BLOCK_SIZE - 1)
422
423/*
424 * bitmap[] structure.  2 bits per HAMMER2_FREEMAP_BLOCK_SIZE.
425 *
426 * 8 x 64-bit elements, 2 bits per block.
427 * 32 blocks (radix 5) per element.
428 * representing INDEX_SIZE bytes worth of storage per element.
429 */
430
431typedef uint64_t			hammer2_bitmap_t;
432
433#define HAMMER2_BMAP_ALLONES		((hammer2_bitmap_t)-1)
434#define HAMMER2_BMAP_ELEMENTS		8
435#define HAMMER2_BMAP_BITS_PER_ELEMENT	64
436#define HAMMER2_BMAP_INDEX_RADIX	5	/* 32 blocks per element */
437#define HAMMER2_BMAP_BLOCKS_PER_ELEMENT	(1 << HAMMER2_BMAP_INDEX_RADIX)
438
439#define HAMMER2_BMAP_INDEX_SIZE		(HAMMER2_FREEMAP_BLOCK_SIZE * \
440					 HAMMER2_BMAP_BLOCKS_PER_ELEMENT)
441#define HAMMER2_BMAP_INDEX_MASK		(HAMMER2_BMAP_INDEX_SIZE - 1)
442
443#define HAMMER2_BMAP_SIZE		(HAMMER2_BMAP_INDEX_SIZE * \
444					 HAMMER2_BMAP_ELEMENTS)
445#define HAMMER2_BMAP_MASK		(HAMMER2_BMAP_SIZE - 1)
446
447/*
448 * Two linear areas can be reserved after the initial 4MB segment in the base
449 * zone (the one starting at offset 0).  These areas are NOT managed by the
450 * block allocator and do not fall under HAMMER2 crc checking rules based
451 * at the volume header (but can be self-CRCd internally, depending).
452 */
453#define HAMMER2_BOOT_MIN_BYTES		HAMMER2_VOLUME_ALIGN
454#define HAMMER2_BOOT_NOM_BYTES		(64*1024*1024)
455#define HAMMER2_BOOT_MAX_BYTES		(256*1024*1024)
456
457#define HAMMER2_REDO_MIN_BYTES		HAMMER2_VOLUME_ALIGN
458#define HAMMER2_REDO_NOM_BYTES		(256*1024*1024)
459#define HAMMER2_REDO_MAX_BYTES		(1024*1024*1024)
460
461/*
462 * Most HAMMER2 types are implemented as unsigned 64-bit integers.
463 * Transaction ids are monotonic.
464 *
465 * We utilize 32-bit iSCSI CRCs.
466 */
467typedef uint64_t hammer2_tid_t;
468typedef uint64_t hammer2_off_t;
469typedef uint64_t hammer2_key_t;
470typedef uint32_t hammer2_crc32_t;
471
472/*
473 * Miscellaneous ranges (all are unsigned).
474 */
475#define HAMMER2_TID_MIN		1ULL
476#define HAMMER2_TID_MAX		0xFFFFFFFFFFFFFFFFULL
477#define HAMMER2_KEY_MIN		0ULL
478#define HAMMER2_KEY_MAX		0xFFFFFFFFFFFFFFFFULL
479#define HAMMER2_OFFSET_MIN	0ULL
480#define HAMMER2_OFFSET_MAX	0xFFFFFFFFFFFFFFFFULL
481
482/*
483 * HAMMER2 data offset special cases and masking.
484 *
485 * All HAMMER2 data offsets have to be broken down into a 64K buffer base
486 * offset (HAMMER2_OFF_MASK_HI) and a 64K buffer index (HAMMER2_OFF_MASK_LO).
487 *
488 * Indexes into physical buffers are always 64-byte aligned.  The low 6 bits
489 * of the data offset field specifies how large the data chunk being pointed
490 * to as a power of 2.  The theoretical minimum radix is thus 6 (The space
491 * needed in the low bits of the data offset field).  However, the practical
492 * minimum allocation chunk size is 1KB (a radix of 10), so HAMMER2 sets
493 * HAMMER2_RADIX_MIN to 10.  The maximum radix is currently 16 (64KB), but
494 * we fully intend to support larger extents in the future.
495 *
496 * WARNING! A radix of 0 (such as when data_off is all 0's) is a special
497 *	    case which means no data associated with the blockref, and
498 *	    not the '1 byte' it would otherwise calculate to.
499 */
500#define HAMMER2_OFF_BAD		((hammer2_off_t)-1)
501#define HAMMER2_OFF_MASK	0xFFFFFFFFFFFFFFC0ULL
502#define HAMMER2_OFF_MASK_LO	(HAMMER2_OFF_MASK & HAMMER2_PBUFMASK64)
503#define HAMMER2_OFF_MASK_HI	(~HAMMER2_PBUFMASK64)
504#define HAMMER2_OFF_MASK_RADIX	0x000000000000003FULL
505#define HAMMER2_MAX_COPIES	6
506
507/*
508 * HAMMER2 directory support and pre-defined keys
509 */
510#define HAMMER2_DIRHASH_VISIBLE	0x8000000000000000ULL
511#define HAMMER2_DIRHASH_USERMSK	0x7FFFFFFFFFFFFFFFULL
512#define HAMMER2_DIRHASH_LOMASK	0x0000000000007FFFULL
513#define HAMMER2_DIRHASH_HIMASK	0xFFFFFFFFFFFF0000ULL
514#define HAMMER2_DIRHASH_FORCED	0x0000000000008000ULL	/* bit forced on */
515
516#define HAMMER2_SROOT_KEY	0x0000000000000000ULL	/* volume to sroot */
517#define HAMMER2_BOOT_KEY	0xd9b36ce135528000ULL	/* sroot to BOOT PFS */
518
519/************************************************************************
520 *				DMSG SUPPORT				*
521 ************************************************************************
522 * LNK_VOLCONF
523 *
524 * All HAMMER2 directories directly under the super-root on your local
525 * media can be mounted separately, even if they share the same physical
526 * device.
527 *
528 * When you do a HAMMER2 mount you are effectively tying into a HAMMER2
529 * cluster via local media.  The local media does not have to participate
530 * in the cluster, other than to provide the hammer2_volconf[] array and
531 * root inode for the mount.
532 *
533 * This is important: The mount device path you specify serves to bootstrap
534 * your entry into the cluster, but your mount will make active connections
535 * to ALL copy elements in the hammer2_volconf[] array which match the
536 * PFSID of the directory in the super-root that you specified.  The local
537 * media path does not have to be mentioned in this array but becomes part
538 * of the cluster based on its type and access rights.  ALL ELEMENTS ARE
539 * TREATED ACCORDING TO TYPE NO MATTER WHICH ONE YOU MOUNT FROM.
540 *
541 * The actual cluster may be far larger than the elements you list in the
542 * hammer2_volconf[] array.  You list only the elements you wish to
543 * directly connect to and you are able to access the rest of the cluster
544 * indirectly through those connections.
545 *
546 * WARNING!  This structure must be exactly 128 bytes long for its config
547 *	     array to fit in the volume header.
548 */
549struct hammer2_volconf {
550	uint8_t	copyid;		/* 00	 copyid 0-255 (must match slot) */
551	uint8_t inprog;		/* 01	 operation in progress, or 0 */
552	uint8_t chain_to;	/* 02	 operation chaining to, or 0 */
553	uint8_t chain_from;	/* 03	 operation chaining from, or 0 */
554	uint16_t flags;		/* 04-05 flags field */
555	uint8_t error;		/* 06	 last operational error */
556	uint8_t priority;	/* 07	 priority and round-robin flag */
557	uint8_t remote_pfs_type;/* 08	 probed direct remote PFS type */
558	uint8_t reserved08[23];	/* 09-1F */
559	uuid_t	pfs_clid;	/* 20-2F copy target must match this uuid */
560	uint8_t label[16];	/* 30-3F import/export label */
561	uint8_t path[64];	/* 40-7F target specification string or key */
562} __packed;
563
564typedef struct hammer2_volconf hammer2_volconf_t;
565
566#define DMSG_VOLF_ENABLED	0x0001
567#define DMSG_VOLF_INPROG	0x0002
568#define DMSG_VOLF_CONN_RR	0x80	/* round-robin at same priority */
569#define DMSG_VOLF_CONN_EF	0x40	/* media errors flagged */
570#define DMSG_VOLF_CONN_PRI	0x0F	/* select priority 0-15 (15=best) */
571
572struct dmsg_lnk_hammer2_volconf {
573	dmsg_hdr_t		head;
574	hammer2_volconf_t	copy;	/* copy spec */
575	int32_t			index;
576	int32_t			unused01;
577	uuid_t			mediaid;
578	int64_t			reserved02[32];
579} __packed;
580
581typedef struct dmsg_lnk_hammer2_volconf dmsg_lnk_hammer2_volconf_t;
582
583#define DMSG_LNK_HAMMER2_VOLCONF DMSG_LNK(DMSG_LNK_CMD_HAMMER2_VOLCONF, \
584					  dmsg_lnk_hammer2_volconf)
585
586#define H2_LNK_VOLCONF(msg)	((dmsg_lnk_hammer2_volconf_t *)(msg)->any.buf)
587
588/*
589 * HAMMER2 directory entry header (embedded in blockref)  exactly 16 bytes
590 */
591struct hammer2_dirent_head {
592	hammer2_tid_t		inum;		/* inode number */
593	uint16_t		namlen;		/* name length */
594	uint8_t			type;		/* OBJTYPE_*	*/
595	uint8_t			unused0B;
596	uint8_t			unused0C[4];
597} __packed;
598
599typedef struct hammer2_dirent_head hammer2_dirent_head_t;
600
601/*
602 * The media block reference structure.  This forms the core of the HAMMER2
603 * media topology recursion.  This 128-byte data structure is embedded in the
604 * volume header, in inodes (which are also directory entries), and in
605 * indirect blocks.
606 *
607 * A blockref references a single media item, which typically can be a
608 * directory entry (aka inode), indirect block, or data block.
609 *
610 * The primary feature a blockref represents is the ability to validate
611 * the entire tree underneath it via its check code.  Any modification to
612 * anything propagates up the blockref tree all the way to the root, replacing
613 * the related blocks and compounding the generated check code.
614 *
615 * The check code can be a simple 32-bit iscsi code, a 64-bit crc, or as
616 * complex as a 512 bit cryptographic hash.  I originally used a 64-byte
617 * blockref but later expanded it to 128 bytes to be able to support the
618 * larger check code as well as to embed statistics for quota operation.
619 *
620 * Simple check codes are not sufficient for unverified dedup.  Even with
621 * a maximally-sized check code unverified dedup should only be used in
622 * subdirectory trees where you do not need 100% data integrity.
623 *
624 * Unverified dedup is deduping based on meta-data only without verifying
625 * that the data blocks are actually identical.  Verified dedup guarantees
626 * integrity but is a far more I/O-expensive operation.
627 *
628 * --
629 *
630 * mirror_tid - per cluster node modified (propagated upward by flush)
631 * modify_tid - clc record modified (not propagated).
632 * update_tid - clc record updated (propagated upward on verification)
633 *
634 * CLC - Stands for 'Cluster Level Change', identifiers which are identical
635 *	 within the topology across all cluster nodes (when fully
636 *	 synchronized).
637 *
638 * NOTE: The range of keys represented by the blockref is (key) to
639 *	 ((key) + (1LL << keybits) - 1).  HAMMER2 usually populates
640 *	 blocks bottom-up, inserting a new root when radix expansion
641 *	 is required.
642 *
643 * leaf_count  - Helps manage leaf collapse calculations when indirect
644 *		 blocks become mostly empty.  This value caps out at
645 *		 HAMMER2_BLOCKREF_LEAF_MAX (65535).
646 *
647 *		 Used by the chain code to determine when to pull leafs up
648 *		 from nearly empty indirect blocks.  For the purposes of this
649 *		 calculation, BREF_TYPE_INODE is considered a leaf, along
650 *		 with DIRENT and DATA.
651 *
652 *				    RESERVED FIELDS
653 *
654 * A number of blockref fields are reserved and should generally be set to
655 * 0 for future compatibility.
656 *
657 *				FUTURE BLOCKREF EXPANSION
658 *
659 * CONTENT ADDRESSABLE INDEXING (future) - Using a 256 or 512-bit check code.
660 */
661struct hammer2_blockref {		/* MUST BE EXACTLY 64 BYTES */
662	uint8_t		type;		/* type of underlying item */
663	uint8_t		methods;	/* check method & compression method */
664	uint8_t		copyid;		/* specify which copy this is */
665	uint8_t		keybits;	/* #of keybits masked off 0=leaf */
666	uint8_t		vradix;		/* virtual data/meta-data size */
667	uint8_t		flags;		/* blockref flags */
668	uint16_t	leaf_count;	/* leaf aggregation count */
669	hammer2_key_t	key;		/* key specification */
670	hammer2_tid_t	mirror_tid;	/* media flush topology & freemap */
671	hammer2_tid_t	modify_tid;	/* clc modify (not propagated) */
672	hammer2_off_t	data_off;	/* low 6 bits is phys size (radix)*/
673	hammer2_tid_t	update_tid;	/* clc modify (propagated upward) */
674	union {
675		char	buf[16];
676
677		/*
678		 * Directory entry header (BREF_TYPE_DIRENT)
679		 *
680		 * NOTE: check.buf contains filename if <= 64 bytes.  Longer
681		 *	 filenames are stored in a data reference of size
682		 *	 HAMMER2_ALLOC_MIN (at least 256, typically 1024).
683		 *
684		 * NOTE: inode structure may contain a copy of a recently
685		 *	 associated filename, for recovery purposes.
686		 *
687		 * NOTE: Superroot entries are INODEs, not DIRENTs.  Code
688		 *	 allows both cases.
689		 */
690		hammer2_dirent_head_t dirent;
691
692		/*
693		 * Statistics aggregation (BREF_TYPE_INODE, BREF_TYPE_INDIRECT)
694		 */
695		struct {
696			hammer2_key_t	data_count;
697			hammer2_key_t	inode_count;
698		} stats;
699	} embed;
700	union {				/* check info */
701		char	buf[64];
702		struct {
703			uint32_t value;
704			uint32_t reserved[15];
705		} iscsi32;
706		struct {
707			uint64_t value;
708			uint64_t reserved[7];
709		} xxhash64;
710		struct {
711			char data[24];
712			char reserved[40];
713		} sha192;
714		struct {
715			char data[32];
716			char reserved[32];
717		} sha256;
718		struct {
719			char data[64];
720		} sha512;
721
722		/*
723		 * Freemap hints are embedded in addition to the icrc32.
724		 *
725		 * bigmask - Radixes available for allocation (0-31).
726		 *	     Heuristical (may be permissive but not
727		 *	     restrictive).  Typically only radix values
728		 *	     10-16 are used (i.e. (1<<10) through (1<<16)).
729		 *
730		 * avail   - Total available space remaining, in bytes
731		 */
732		struct {
733			uint32_t icrc32;
734			uint32_t bigmask;	/* available radixes */
735			uint64_t avail;		/* total available bytes */
736			char reserved[48];
737		} freemap;
738	} check;
739} __packed;
740
741typedef struct hammer2_blockref hammer2_blockref_t;
742
743#define HAMMER2_BLOCKREF_BYTES		128	/* blockref struct in bytes */
744#define HAMMER2_BLOCKREF_RADIX		7
745
746#define HAMMER2_BLOCKREF_LEAF_MAX	65535
747
748/*
749 * On-media and off-media blockref types.
750 *
751 * types >= 128 are pseudo values that should never be present on-media.
752 */
753#define HAMMER2_BREF_TYPE_EMPTY		0
754#define HAMMER2_BREF_TYPE_INODE		1
755#define HAMMER2_BREF_TYPE_INDIRECT	2
756#define HAMMER2_BREF_TYPE_DATA		3
757#define HAMMER2_BREF_TYPE_DIRENT	4
758#define HAMMER2_BREF_TYPE_FREEMAP_NODE	5
759#define HAMMER2_BREF_TYPE_FREEMAP_LEAF	6
760#define HAMMER2_BREF_TYPE_FREEMAP	254	/* pseudo-type */
761#define HAMMER2_BREF_TYPE_VOLUME	255	/* pseudo-type */
762
763#define HAMMER2_BREF_FLAG_PFSROOT	0x01	/* see also related opflag */
764#define HAMMER2_BREF_FLAG_ZERO		0x02
765
766/*
767 * Encode/decode check mode and compression mode for
768 * bref.methods.  The compression level is not encoded in
769 * bref.methods.
770 */
771#define HAMMER2_ENC_CHECK(n)		(((n) & 15) << 4)
772#define HAMMER2_DEC_CHECK(n)		(((n) >> 4) & 15)
773#define HAMMER2_ENC_COMP(n)		((n) & 15)
774#define HAMMER2_DEC_COMP(n)		((n) & 15)
775
776#define HAMMER2_CHECK_NONE		0
777#define HAMMER2_CHECK_DISABLED		1
778#define HAMMER2_CHECK_ISCSI32		2
779#define HAMMER2_CHECK_XXHASH64		3
780#define HAMMER2_CHECK_SHA192		4
781#define HAMMER2_CHECK_FREEMAP		5
782
783#define HAMMER2_CHECK_DEFAULT		HAMMER2_CHECK_XXHASH64
784
785/* user-specifiable check modes only */
786#define HAMMER2_CHECK_STRINGS		{ "none", "disabled", "crc32", \
787					  "xxhash64", "sha192" }
788#define HAMMER2_CHECK_STRINGS_COUNT	5
789
790/*
791 * Encode/decode check or compression algorithm request in
792 * ipdata->meta.check_algo and ipdata->meta.comp_algo.
793 */
794#define HAMMER2_ENC_ALGO(n)		(n)
795#define HAMMER2_DEC_ALGO(n)		((n) & 15)
796#define HAMMER2_ENC_LEVEL(n)		((n) << 4)
797#define HAMMER2_DEC_LEVEL(n)		(((n) >> 4) & 15)
798
799#define HAMMER2_COMP_NONE		0
800#define HAMMER2_COMP_AUTOZERO		1
801#define HAMMER2_COMP_LZ4		2
802#define HAMMER2_COMP_ZLIB		3
803
804#define HAMMER2_COMP_NEWFS_DEFAULT	HAMMER2_COMP_LZ4
805#define HAMMER2_COMP_STRINGS		{ "none", "autozero", "lz4", "zlib" }
806#define HAMMER2_COMP_STRINGS_COUNT	4
807
808/*
809 * Passed to hammer2_chain_create(), causes methods to be inherited from
810 * parent.
811 */
812#define HAMMER2_METH_DEFAULT		-1
813
814/*
815 * HAMMER2 block references are collected into sets of 4 blockrefs.  These
816 * sets are fully associative, meaning the elements making up a set are
817 * not sorted in any way and may contain duplicate entries, holes, or
818 * entries which shortcut multiple levels of indirection.  Sets are used
819 * in various ways:
820 *
821 * (1) When redundancy is desired a set may contain several duplicate
822 *     entries pointing to different copies of the same data.  Up to 4 copies
823 *     are supported.
824 *
825 * (2) The blockrefs in a set can shortcut multiple levels of indirections
826 *     within the bounds imposed by the parent of set.
827 *
828 * When a set fills up another level of indirection is inserted, moving
829 * some or all of the set's contents into indirect blocks placed under the
830 * set.  This is a top-down approach in that indirect blocks are not created
831 * until the set actually becomes full (that is, the entries in the set can
832 * shortcut the indirect blocks when the set is not full).  Depending on how
833 * things are filled multiple indirect blocks will eventually be created.
834 *
835 * Indirect blocks are typically 4KB (64 entres) or 64KB (1024 entries) and
836 * are also treated as fully set-associative.
837 */
838struct hammer2_blockset {
839	hammer2_blockref_t	blockref[HAMMER2_SET_COUNT];
840};
841
842typedef struct hammer2_blockset hammer2_blockset_t;
843
844/*
845 * Catch programmer snafus
846 */
847#if (1 << HAMMER2_SET_RADIX) != HAMMER2_SET_COUNT
848#error "hammer2 direct radix is incorrect"
849#endif
850#if (1 << HAMMER2_PBUFRADIX) != HAMMER2_PBUFSIZE
851#error "HAMMER2_PBUFRADIX and HAMMER2_PBUFSIZE are inconsistent"
852#endif
853#if (1 << HAMMER2_RADIX_MIN) != HAMMER2_ALLOC_MIN
854#error "HAMMER2_RADIX_MIN and HAMMER2_ALLOC_MIN are inconsistent"
855#endif
856
857/*
858 * hammer2_bmap_data - A freemap entry in the LEVEL1 block.
859 *
860 * Each 128-byte entry contains the bitmap and meta-data required to manage
861 * a LEVEL0 (4MB) block of storage.  The storage is managed in 256 x 16KB
862 * chunks.
863 *
864 * A smaller allocation granularity is supported via a linear iterator and/or
865 * must otherwise be tracked in ram.
866 *
867 * (data structure must be 128 bytes exactly)
868 *
869 * linear  - A BYTE linear allocation offset used for sub-16KB allocations
870 *	     only.  May contain values between 0 and 4MB.  Must be ignored
871 *	     if 16KB-aligned (i.e. force bitmap scan), otherwise may be
872 *	     used to sub-allocate within the 16KB block (which is already
873 *	     marked as allocated in the bitmap).
874 *
875 *	     Sub-allocations need only be 1KB-aligned and do not have to be
876 *	     size-aligned, and 16KB or larger allocations do not update this
877 *	     field, resulting in pretty good packing.
878 *
879 *	     Please note that file data granularity may be limited by
880 *	     other issues such as buffer cache direct-mapping and the
881 *	     desire to support sector sizes up to 16KB (so H2 only issues
882 *	     I/O's in multiples of 16KB anyway).
883 *
884 * class   - Clustering class.  Cleared to 0 only if the entire leaf becomes
885 *	     free.  Used to cluster device buffers so all elements must have
886 *	     the same device block size, but may mix logical sizes.
887 *
888 *	     Typically integrated with the blockref type in the upper 8 bits
889 *	     to localize inodes and indrect blocks, improving bulk free scans
890 *	     and directory scans.
891 *
892 * bitmap  - Two bits per 16KB allocation block arranged in arrays of
893 *	     64-bit elements, 256x2 bits representing ~4MB worth of media
894 *	     storage.  Bit patterns are as follows:
895 *
896 *	     00	Unallocated
897 *	     01 (reserved)
898 *	     10 Possibly free
899 *           11 Allocated
900 */
901struct hammer2_bmap_data {
902	int32_t linear;		/* 00 linear sub-granular allocation offset */
903	uint16_t class;		/* 04-05 clustering class ((type<<8)|radix) */
904	uint8_t reserved06;	/* 06 */
905	uint8_t reserved07;	/* 07 */
906	uint32_t reserved08;	/* 08 */
907	uint32_t reserved0C;	/* 0C */
908	uint32_t reserved10;	/* 10 */
909	uint32_t reserved14;	/* 14 */
910	uint32_t reserved18;	/* 18 */
911	uint32_t avail;		/* 1C */
912	uint32_t reserved20[8];	/* 20-3F 256 bits manages 128K/1KB/2-bits */
913				/* 40-7F 512 bits manages 4MB of storage */
914	hammer2_bitmap_t bitmapq[HAMMER2_BMAP_ELEMENTS];
915} __packed;
916
917typedef struct hammer2_bmap_data hammer2_bmap_data_t;
918
919/*
920 * XXX "Inodes ARE directory entries" is no longer the case.  Hardlinks are
921 * dirents which refer to the same inode#, which is how filesystems usually
922 * implement hardlink.  The following comments need to be updated.
923 *
924 * In HAMMER2 inodes ARE directory entries, with a special exception for
925 * hardlinks.  The inode number is stored in the inode rather than being
926 * based on the location of the inode (since the location moves every time
927 * the inode or anything underneath the inode is modified).
928 *
929 * The inode is 1024 bytes, made up of 256 bytes of meta-data, 256 bytes
930 * for the filename, and 512 bytes worth of direct file data OR an embedded
931 * blockset.  The in-memory hammer2_inode structure contains only the mostly-
932 * node-independent meta-data portion (some flags are node-specific and will
933 * not be synchronized).  The rest of the inode is node-specific and chain I/O
934 * is required to obtain it.
935 *
936 * Directories represent one inode per blockref.  Inodes are not laid out
937 * as a file but instead are represented by the related blockrefs.  The
938 * blockrefs, in turn, are indexed by the 64-bit directory hash key.  Remember
939 * that blocksets are fully associative, so a certain degree efficiency is
940 * achieved just from that.
941 *
942 * Up to 512 bytes of direct data can be embedded in an inode, and since
943 * inodes are essentially directory entries this also means that small data
944 * files end up simply being laid out linearly in the directory, resulting
945 * in fewer seeks and highly optimal access.
946 *
947 * The compression mode can be changed at any time in the inode and is
948 * recorded on a blockref-by-blockref basis.
949 *
950 * Hardlinks are supported via the inode map.  Essentially the way a hardlink
951 * works is that all individual directory entries representing the same file
952 * are special cased and specify the same inode number.  The actual file
953 * is placed in the nearest parent directory that is parent to all instances
954 * of the hardlink.  If all hardlinks to a file are in the same directory
955 * the actual file will also be placed in that directory.  This file uses
956 * the inode number as the directory entry key and is invisible to normal
957 * directory scans.  Real directory entry keys are differentiated from the
958 * inode number key via bit 63.  Access to the hardlink silently looks up
959 * the real file and forwards all operations to that file.  Removal of the
960 * last hardlink also removes the real file.
961 */
962#define HAMMER2_INODE_BYTES		1024	/* (asserted by code) */
963#define HAMMER2_INODE_MAXNAME		256	/* maximum name in bytes */
964#define HAMMER2_INODE_VERSION_ONE	1
965
966#define HAMMER2_INODE_START		1024	/* dynamically allocated */
967
968struct hammer2_inode_meta {
969	uint16_t	version;	/* 0000 inode data version */
970	uint8_t		reserved02;	/* 0002 */
971	uint8_t		pfs_subtype;	/* 0003 pfs sub-type */
972
973	/*
974	 * core inode attributes, inode type, misc flags
975	 */
976	uint32_t	uflags;		/* 0004 chflags */
977	uint32_t	rmajor;		/* 0008 available for device nodes */
978	uint32_t	rminor;		/* 000C available for device nodes */
979	uint64_t	ctime;		/* 0010 inode change time */
980	uint64_t	mtime;		/* 0018 modified time */
981	uint64_t	atime;		/* 0020 access time (unsupported) */
982	uint64_t	btime;		/* 0028 birth time */
983	uuid_t		uid;		/* 0030 uid / degenerate unix uid */
984	uuid_t		gid;		/* 0040 gid / degenerate unix gid */
985
986	uint8_t		type;		/* 0050 object type */
987	uint8_t		op_flags;	/* 0051 operational flags */
988	uint16_t	cap_flags;	/* 0052 capability flags */
989	uint32_t	mode;		/* 0054 unix modes (typ low 16 bits) */
990
991	/*
992	 * inode size, identification, localized recursive configuration
993	 * for compression and backup copies.
994	 *
995	 * NOTE: Nominal parent inode number (iparent) is only applicable
996	 *	 for directories but can also help for files during
997	 *	 catastrophic recovery.
998	 */
999	hammer2_tid_t	inum;		/* 0058 inode number */
1000	hammer2_off_t	size;		/* 0060 size of file */
1001	uint64_t	nlinks;		/* 0068 hard links (typ only dirs) */
1002	hammer2_tid_t	iparent;	/* 0070 nominal parent inum */
1003	hammer2_key_t	name_key;	/* 0078 full filename key */
1004	uint16_t	name_len;	/* 0080 filename length */
1005	uint8_t		ncopies;	/* 0082 ncopies to local media */
1006	uint8_t		comp_algo;	/* 0083 compression request & algo */
1007
1008	/*
1009	 * These fields are currently only applicable to PFSROOTs.
1010	 *
1011	 * NOTE: We can't use {volume_data->fsid, pfs_clid} to uniquely
1012	 *	 identify an instance of a PFS in the cluster because
1013	 *	 a mount may contain more than one copy of the PFS as
1014	 *	 a separate node.  {pfs_clid, pfs_fsid} must be used for
1015	 *	 registration in the cluster.
1016	 */
1017	uint8_t		target_type;	/* 0084 hardlink target type */
1018	uint8_t		check_algo;	/* 0085 check code request & algo */
1019	uint8_t		pfs_nmasters;	/* 0086 (if PFSROOT) if multi-master */
1020	uint8_t		pfs_type;	/* 0087 (if PFSROOT) node type */
1021	uint64_t	pfs_inum;	/* 0088 (if PFSROOT) inum allocator */
1022	uuid_t		pfs_clid;	/* 0090 (if PFSROOT) cluster uuid */
1023	uuid_t		pfs_fsid;	/* 00A0 (if PFSROOT) unique uuid */
1024
1025	/*
1026	 * Quotas and aggregate sub-tree inode and data counters.  Note that
1027	 * quotas are not replicated downward, they are explicitly set by
1028	 * the sysop and in-memory structures keep track of inheritance.
1029	 */
1030	hammer2_key_t	data_quota;	/* 00B0 subtree quota in bytes */
1031	hammer2_key_t	unusedB8;	/* 00B8 subtree byte count */
1032	hammer2_key_t	inode_quota;	/* 00C0 subtree quota inode count */
1033	hammer2_key_t	unusedC8;	/* 00C8 subtree inode count */
1034
1035	/*
1036	 * The last snapshot tid is tested against modify_tid to determine
1037	 * when a copy must be made of a data block whos check mode has been
1038	 * disabled (a disabled check mode allows data blocks to be updated
1039	 * in place instead of copy-on-write).
1040	 */
1041	hammer2_tid_t	pfs_lsnap_tid;	/* 00D0 last snapshot tid */
1042	hammer2_tid_t	reservedD8;	/* 00D8 (avail) */
1043
1044	/*
1045	 * Tracks (possibly degenerate) free areas covering all sub-tree
1046	 * allocations under inode, not counting the inode itself.
1047	 * 0/0 indicates empty entry.  fully set-associative.
1048	 *
1049	 * (not yet implemented)
1050	 */
1051	uint64_t	decrypt_check;	/* 00E0 decryption validator */
1052	hammer2_off_t	reservedE0[3];	/* 00E8/F0/F8 */
1053} __packed;
1054
1055typedef struct hammer2_inode_meta hammer2_inode_meta_t;
1056
1057struct hammer2_inode_data {
1058	hammer2_inode_meta_t	meta;	/* 0000-00FF */
1059	unsigned char	filename[HAMMER2_INODE_MAXNAME];
1060					/* 0100-01FF (256 char, unterminated) */
1061	union {				/* 0200-03FF (64x8 = 512 bytes) */
1062		hammer2_blockset_t blockset;
1063		char data[HAMMER2_EMBEDDED_BYTES];
1064	} u;
1065} __packed;
1066
1067typedef struct hammer2_inode_data hammer2_inode_data_t;
1068
1069#define HAMMER2_OPFLAG_DIRECTDATA	0x01
1070#define HAMMER2_OPFLAG_PFSROOT		0x02	/* (see also bref flag) */
1071#define HAMMER2_OPFLAG_COPYIDS		0x04	/* copyids override parent */
1072
1073#define HAMMER2_OBJTYPE_UNKNOWN		0
1074#define HAMMER2_OBJTYPE_DIRECTORY	1
1075#define HAMMER2_OBJTYPE_REGFILE		2
1076#define HAMMER2_OBJTYPE_FIFO		4
1077#define HAMMER2_OBJTYPE_CDEV		5
1078#define HAMMER2_OBJTYPE_BDEV		6
1079#define HAMMER2_OBJTYPE_SOFTLINK	7
1080#define HAMMER2_OBJTYPE_UNUSED08	8
1081#define HAMMER2_OBJTYPE_SOCKET		9
1082#define HAMMER2_OBJTYPE_WHITEOUT	10
1083
1084#define HAMMER2_COPYID_NONE		0
1085#define HAMMER2_COPYID_LOCAL		((uint8_t)-1)
1086
1087#define HAMMER2_COPYID_COUNT		256
1088
1089/*
1090 * PFS types identify the role of a PFS within a cluster.  The PFS types
1091 * is stored on media and in LNK_SPAN messages and used in other places.
1092 *
1093 * The low 4 bits specify the current active type while the high 4 bits
1094 * specify the transition target if the PFS is being upgraded or downgraded,
1095 * If the upper 4 bits are not zero it may effect how a PFS is used during
1096 * the transition.
1097 *
1098 * Generally speaking, downgrading a MASTER to a SLAVE cannot complete until
1099 * at least all MASTERs have updated their pfs_nmasters field.  And upgrading
1100 * a SLAVE to a MASTER cannot complete until the new prospective master has
1101 * been fully synchronized (though theoretically full synchronization is
1102 * not required if a (new) quorum of other masters are fully synchronized).
1103 *
1104 * It generally does not matter which PFS element you actually mount, you
1105 * are mounting 'the cluster'.  So, for example, a network mount will mount
1106 * a DUMMY PFS type on a memory filesystem.  However, there are two exceptions.
1107 * In order to gain the benefits of a SOFT_MASTER or SOFT_SLAVE, those PFSs
1108 * must be directly mounted.
1109 */
1110#define HAMMER2_PFSTYPE_NONE		0x00
1111#define HAMMER2_PFSTYPE_CACHE		0x01
1112#define HAMMER2_PFSTYPE_UNUSED02	0x02
1113#define HAMMER2_PFSTYPE_SLAVE		0x03
1114#define HAMMER2_PFSTYPE_SOFT_SLAVE	0x04
1115#define HAMMER2_PFSTYPE_SOFT_MASTER	0x05
1116#define HAMMER2_PFSTYPE_MASTER		0x06
1117#define HAMMER2_PFSTYPE_UNUSED07	0x07
1118#define HAMMER2_PFSTYPE_SUPROOT		0x08
1119#define HAMMER2_PFSTYPE_DUMMY		0x09
1120#define HAMMER2_PFSTYPE_MAX		16
1121
1122#define HAMMER2_PFSTRAN_NONE		0x00	/* no transition in progress */
1123#define HAMMER2_PFSTRAN_CACHE		0x10
1124#define HAMMER2_PFSTRAN_UNMUSED20	0x20
1125#define HAMMER2_PFSTRAN_SLAVE		0x30
1126#define HAMMER2_PFSTRAN_SOFT_SLAVE	0x40
1127#define HAMMER2_PFSTRAN_SOFT_MASTER	0x50
1128#define HAMMER2_PFSTRAN_MASTER		0x60
1129#define HAMMER2_PFSTRAN_UNUSED70	0x70
1130#define HAMMER2_PFSTRAN_SUPROOT		0x80
1131#define HAMMER2_PFSTRAN_DUMMY		0x90
1132
1133#define HAMMER2_PFS_DEC(n)		((n) & 0x0F)
1134#define HAMMER2_PFS_DEC_TRANSITION(n)	(((n) >> 4) & 0x0F)
1135#define HAMMER2_PFS_ENC_TRANSITION(n)	(((n) & 0x0F) << 4)
1136
1137#define HAMMER2_PFSSUBTYPE_NONE		0
1138#define HAMMER2_PFSSUBTYPE_SNAPSHOT	1	/* manual/managed snapshot */
1139#define HAMMER2_PFSSUBTYPE_AUTOSNAP	2	/* automatic snapshot */
1140
1141/*
1142 * PFS mode of operation is a bitmask.  This is typically not stored
1143 * on-media, but defined here because the field may be used in dmsgs.
1144 */
1145#define HAMMER2_PFSMODE_QUORUM		0x01
1146#define HAMMER2_PFSMODE_RW		0x02
1147
1148/*
1149 *				Allocation Table
1150 *
1151 */
1152
1153
1154/*
1155 * Flags (8 bits) - blockref, for freemap only
1156 *
1157 * Note that the minimum chunk size is 1KB so we could theoretically have
1158 * 10 bits here, but we might have some future extension that allows a
1159 * chunk size down to 256 bytes and if so we will need bits 8 and 9.
1160 */
1161#define HAMMER2_AVF_SELMASK		0x03	/* select group */
1162#define HAMMER2_AVF_ALL_ALLOC		0x04	/* indicate all allocated */
1163#define HAMMER2_AVF_ALL_FREE		0x08	/* indicate all free */
1164#define HAMMER2_AVF_RESERVED10		0x10
1165#define HAMMER2_AVF_RESERVED20		0x20
1166#define HAMMER2_AVF_RESERVED40		0x40
1167#define HAMMER2_AVF_RESERVED80		0x80
1168#define HAMMER2_AVF_AVMASK32		((uint32_t)0xFFFFFF00LU)
1169#define HAMMER2_AVF_AVMASK64		((uint64_t)0xFFFFFFFFFFFFFF00LLU)
1170
1171#define HAMMER2_AV_SELECT_A		0x00
1172#define HAMMER2_AV_SELECT_B		0x01
1173#define HAMMER2_AV_SELECT_C		0x02
1174#define HAMMER2_AV_SELECT_D		0x03
1175
1176/*
1177 * The volume header eats a 64K block.  There is currently an issue where
1178 * we want to try to fit all nominal filesystem updates in a 512-byte section
1179 * but it may be a lost cause due to the need for a blockset.
1180 *
1181 * All information is stored in host byte order.  The volume header's magic
1182 * number may be checked to determine the byte order.  If you wish to mount
1183 * between machines w/ different endian modes you'll need filesystem code
1184 * which acts on the media data consistently (either all one way or all the
1185 * other).  Our code currently does not do that.
1186 *
1187 * A read-write mount may have to recover missing allocations by doing an
1188 * incremental mirror scan looking for modifications made after alloc_tid.
1189 * If alloc_tid == last_tid then no recovery operation is needed.  Recovery
1190 * operations are usually very, very fast.
1191 *
1192 * Read-only mounts do not need to do any recovery, access to the filesystem
1193 * topology is always consistent after a crash (is always consistent, period).
1194 * However, there may be shortcutted blockref updates present from deep in
1195 * the tree which are stored in the volumeh eader and must be tracked on
1196 * the fly.
1197 *
1198 * NOTE: The copyinfo[] array contains the configuration for both the
1199 *	 cluster connections and any local media copies.  The volume
1200 *	 header will be replicated for each local media copy.
1201 *
1202 *	 The mount command may specify multiple medias or just one and
1203 *	 allow HAMMER2 to pick up the others when it checks the copyinfo[]
1204 *	 array on mount.
1205 *
1206 * NOTE: root_blockref points to the super-root directory, not the root
1207 *	 directory.  The root directory will be a subdirectory under the
1208 *	 super-root.
1209 *
1210 *	 The super-root directory contains all root directories and all
1211 *	 snapshots (readonly or writable).  It is possible to do a
1212 *	 null-mount of the super-root using special path constructions
1213 *	 relative to your mounted root.
1214 *
1215 * NOTE: HAMMER2 allows any subdirectory tree to be managed as if it were
1216 *	 a PFS, including mirroring and storage quota operations, and this is
1217 *	 preferred over creating discrete PFSs in the super-root.  Instead
1218 *	 the super-root is most typically used to create writable snapshots,
1219 *	 alternative roots, and so forth.  The super-root is also used by
1220 *	 the automatic snapshotting mechanism.
1221 */
1222#define HAMMER2_VOLUME_ID_HBO	0x48414d3205172011LLU
1223#define HAMMER2_VOLUME_ID_ABO	0x11201705324d4148LLU
1224
1225struct hammer2_volume_data {
1226	/*
1227	 * sector #0 - 512 bytes
1228	 */
1229	uint64_t	magic;			/* 0000 Signature */
1230	hammer2_off_t	boot_beg;		/* 0008 Boot area (future) */
1231	hammer2_off_t	boot_end;		/* 0010 (size = end - beg) */
1232	hammer2_off_t	aux_beg;		/* 0018 Aux area (future) */
1233	hammer2_off_t	aux_end;		/* 0020 (size = end - beg) */
1234	hammer2_off_t	volu_size;		/* 0028 Volume size, bytes */
1235
1236	uint32_t	version;		/* 0030 */
1237	uint32_t	flags;			/* 0034 */
1238	uint8_t		copyid;			/* 0038 copyid of phys vol */
1239	uint8_t		freemap_version;	/* 0039 freemap algorithm */
1240	uint8_t		peer_type;		/* 003A HAMMER2_PEER_xxx */
1241	uint8_t		reserved003B;		/* 003B */
1242	uint32_t	reserved003C;		/* 003C */
1243
1244	uuid_t		fsid;			/* 0040 */
1245	uuid_t		fstype;			/* 0050 */
1246
1247	/*
1248	 * allocator_size is precalculated at newfs time and does not include
1249	 * reserved blocks, boot, or redo areas.
1250	 *
1251	 * Initial non-reserved-area allocations do not use the freemap
1252	 * but instead adjust alloc_iterator.  Dynamic allocations take
1253	 * over starting at (allocator_beg).  This makes newfs_hammer2's
1254	 * job a lot easier and can also serve as a testing jig.
1255	 */
1256	hammer2_off_t	allocator_size;		/* 0060 Total data space */
1257	hammer2_off_t   allocator_free;		/* 0068	Free space */
1258	hammer2_off_t	allocator_beg;		/* 0070 Initial allocations */
1259
1260	/*
1261	 * mirror_tid reflects the highest committed change for this
1262	 * block device regardless of whether it is to the super-root
1263	 * or to a PFS or whatever.
1264	 *
1265	 * freemap_tid reflects the highest committed freemap change for
1266	 * this block device.
1267	 */
1268	hammer2_tid_t	mirror_tid;		/* 0078 committed tid (vol) */
1269	hammer2_tid_t	reserved0080;		/* 0080 */
1270	hammer2_tid_t	reserved0088;		/* 0088 */
1271	hammer2_tid_t	freemap_tid;		/* 0090 committed tid (fmap) */
1272	hammer2_tid_t	bulkfree_tid;		/* 0098 bulkfree incremental */
1273	hammer2_tid_t	reserved00A0[5];	/* 00A0-00C7 */
1274
1275	/*
1276	 * Copyids are allocated dynamically from the copyexists bitmap.
1277	 * An id from the active copies set (up to 8, see copyinfo later on)
1278	 * may still exist after the copy set has been removed from the
1279	 * volume header and its bit will remain active in the bitmap and
1280	 * cannot be reused until it is 100% removed from the hierarchy.
1281	 */
1282	uint32_t	copyexists[8];		/* 00C8-00E7 copy exists bmap */
1283	char		reserved0140[248];	/* 00E8-01DF */
1284
1285	/*
1286	 * 32 bit CRC array at the end of the first 512 byte sector.
1287	 *
1288	 * icrc_sects[7] - First 512-4 bytes of volume header (including all
1289	 *		   the other icrc's except this one).
1290	 *
1291	 * icrc_sects[6] - Sector 1 (512 bytes) of volume header, which is
1292	 *		   the blockset for the root.
1293	 *
1294	 * icrc_sects[5] - Sector 2
1295	 * icrc_sects[4] - Sector 3
1296	 * icrc_sects[3] - Sector 4 (the freemap blockset)
1297	 */
1298	hammer2_crc32_t	icrc_sects[8];		/* 01E0-01FF */
1299
1300	/*
1301	 * sector #1 - 512 bytes
1302	 *
1303	 * The entire sector is used by a blockset.
1304	 */
1305	hammer2_blockset_t sroot_blockset;	/* 0200-03FF Superroot dir */
1306
1307	/*
1308	 * sector #2-7
1309	 */
1310	char	sector2[512];			/* 0400-05FF reserved */
1311	char	sector3[512];			/* 0600-07FF reserved */
1312	hammer2_blockset_t freemap_blockset;	/* 0800-09FF freemap  */
1313	char	sector5[512];			/* 0A00-0BFF reserved */
1314	char	sector6[512];			/* 0C00-0DFF reserved */
1315	char	sector7[512];			/* 0E00-0FFF reserved */
1316
1317	/*
1318	 * sector #8-71	- 32768 bytes
1319	 *
1320	 * Contains the configuration for up to 256 copyinfo targets.  These
1321	 * specify local and remote copies operating as masters or slaves.
1322	 * copyid's 0 and 255 are reserved (0 indicates an empty slot and 255
1323	 * indicates the local media).
1324	 *
1325	 * Each inode contains a set of up to 8 copyids, either inherited
1326	 * from its parent or explicitly specified in the inode, which
1327	 * indexes into this array.
1328	 */
1329						/* 1000-8FFF copyinfo config */
1330	hammer2_volconf_t copyinfo[HAMMER2_COPYID_COUNT];
1331
1332	/*
1333	 * Remaining sections are reserved for future use.
1334	 */
1335	char		reserved0400[0x6FFC];	/* 9000-FFFB reserved */
1336
1337	/*
1338	 * icrc on entire volume header
1339	 */
1340	hammer2_crc32_t	icrc_volheader;		/* FFFC-FFFF full volume icrc*/
1341} __packed;
1342
1343typedef struct hammer2_volume_data hammer2_volume_data_t;
1344
1345/*
1346 * Various parts of the volume header have their own iCRCs.
1347 *
1348 * The first 512 bytes has its own iCRC stored at the end of the 512 bytes
1349 * and not included the icrc calculation.
1350 *
1351 * The second 512 bytes also has its own iCRC but it is stored in the first
1352 * 512 bytes so it covers the entire second 512 bytes.
1353 *
1354 * The whole volume block (64KB) has an iCRC covering all but the last 4 bytes,
1355 * which is where the iCRC for the whole volume is stored.  This is currently
1356 * a catch-all for anything not individually iCRCd.
1357 */
1358#define HAMMER2_VOL_ICRC_SECT0		7
1359#define HAMMER2_VOL_ICRC_SECT1		6
1360
1361#define HAMMER2_VOLUME_BYTES		65536
1362
1363#define HAMMER2_VOLUME_ICRC0_OFF	0
1364#define HAMMER2_VOLUME_ICRC1_OFF	512
1365#define HAMMER2_VOLUME_ICRCVH_OFF	0
1366
1367#define HAMMER2_VOLUME_ICRC0_SIZE	(512 - 4)
1368#define HAMMER2_VOLUME_ICRC1_SIZE	(512)
1369#define HAMMER2_VOLUME_ICRCVH_SIZE	(65536 - 4)
1370
1371#define HAMMER2_VOL_VERSION_MIN		1
1372#define HAMMER2_VOL_VERSION_DEFAULT	1
1373#define HAMMER2_VOL_VERSION_WIP 	2
1374
1375#define HAMMER2_NUM_VOLHDRS		4
1376
1377union hammer2_media_data {
1378	hammer2_volume_data_t	voldata;
1379        hammer2_inode_data_t    ipdata;
1380	hammer2_blockset_t	blkset;
1381	hammer2_blockref_t	npdata[HAMMER2_IND_COUNT_MAX];
1382	hammer2_bmap_data_t	bmdata[HAMMER2_FREEMAP_COUNT];
1383	char			buf[HAMMER2_PBUFSIZE];
1384} __packed;
1385
1386typedef union hammer2_media_data hammer2_media_data_t;
1387
1388#endif /* !_HAMMER2_DISK_H_ */
1389