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 <[email protected]>
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
35#ifndef VFS_HAMMER_DISK_H_
36#define VFS_HAMMER_DISK_H_
37
38#include <sys/endian.h>
39#include <sys/types.h>
40
41#ifndef _SYS_UUID_H_
42#include <sys/uuid.h>
43#endif
44
45/*
46 * The structures below represent the on-disk format for a HAMMER
47 * filesystem.  Note that all fields for on-disk structures are naturally
48 * aligned.  HAMMER uses little endian for fields in on-disk structures.
49 * HAMMER doesn't support big endian arch, but is planned.
50 *
51 * Most of HAMMER revolves around the concept of an object identifier.  An
52 * obj_id is a 64 bit quantity which uniquely identifies a filesystem object
53 * FOR THE ENTIRE LIFE OF THE FILESYSTEM.  This uniqueness allows backups
54 * and mirrors to retain varying amounts of filesystem history by removing
55 * any possibility of conflict through identifier reuse.
56 *
57 * A HAMMER filesystem may span multiple volumes.
58 *
59 * A HAMMER filesystem uses a 16K filesystem buffer size.  All filesystem
60 * I/O is done in multiples of 16K.
61 *
62 * 64K X-bufs are used for blocks >= a file's 1MB mark.
63 *
64 * Per-volume storage limit: 52 bits        4096 TB
65 * Per-Zone storage limit: 60 bits      1 MTB
66 * Per-filesystem storage limit: 60 bits    1 MTB
67 */
68#define HAMMER_BUFSIZE      16384
69#define HAMMER_XBUFSIZE     65536
70#define HAMMER_HBUFSIZE     (HAMMER_BUFSIZE / 2)
71#define HAMMER_XDEMARC      (1024 * 1024)
72#define HAMMER_BUFMASK      (HAMMER_BUFSIZE - 1)
73#define HAMMER_XBUFMASK     (HAMMER_XBUFSIZE - 1)
74
75#define HAMMER_BUFSIZE64    ((uint64_t)HAMMER_BUFSIZE)
76#define HAMMER_BUFMASK64    ((uint64_t)HAMMER_BUFMASK)
77
78#define HAMMER_XBUFSIZE64   ((uint64_t)HAMMER_XBUFSIZE)
79#define HAMMER_XBUFMASK64   ((uint64_t)HAMMER_XBUFMASK)
80
81#define HAMMER_OFF_ZONE_MASK    0xF000000000000000ULL /* zone portion */
82#define HAMMER_OFF_VOL_MASK 0x0FF0000000000000ULL /* volume portion */
83#define HAMMER_OFF_SHORT_MASK   0x000FFFFFFFFFFFFFULL /* offset portion */
84#define HAMMER_OFF_LONG_MASK    0x0FFFFFFFFFFFFFFFULL /* offset portion */
85
86#define HAMMER_OFF_BAD      ((hammer_off_t)-1)
87
88#define HAMMER_BUFSIZE_DOALIGN(offset)              \
89    (((offset) + HAMMER_BUFMASK) & ~HAMMER_BUFMASK)
90#define HAMMER_BUFSIZE64_DOALIGN(offset)            \
91    (((offset) + HAMMER_BUFMASK64) & ~HAMMER_BUFMASK64)
92
93#define HAMMER_XBUFSIZE_DOALIGN(offset)             \
94    (((offset) + HAMMER_XBUFMASK) & ~HAMMER_XBUFMASK)
95#define HAMMER_XBUFSIZE64_DOALIGN(offset)           \
96    (((offset) + HAMMER_XBUFMASK64) & ~HAMMER_XBUFMASK64)
97
98/*
99 * The current limit of volumes that can make up a HAMMER FS
100 */
101#define HAMMER_MAX_VOLUMES  256
102
103/*
104 * Reserved space for (future) header junk after the volume header.
105 */
106#define HAMMER_MIN_VOL_JUNK (HAMMER_BUFSIZE * 16)   /* 256 KB */
107#define HAMMER_MAX_VOL_JUNK HAMMER_MIN_VOL_JUNK
108#define HAMMER_VOL_JUNK_SIZE    HAMMER_MIN_VOL_JUNK
109
110/*
111 * Hammer transaction ids are 64 bit unsigned integers and are usually
112 * synchronized with the time of day in nanoseconds.
113 *
114 * Hammer offsets are used for FIFO indexing and embed a cycle counter
115 * and volume number in addition to the offset.  Most offsets are required
116 * to be 16 KB aligned.
117 */
118typedef uint64_t hammer_tid_t;
119typedef uint64_t hammer_off_t;
120typedef uint32_t hammer_crc_t;
121typedef uuid_t hammer_uuid_t;
122
123#define HAMMER_MIN_TID      0ULL            /* unsigned */
124#define HAMMER_MAX_TID      0xFFFFFFFFFFFFFFFFULL   /* unsigned */
125#define HAMMER_MIN_KEY      -0x8000000000000000LL   /* signed */
126#define HAMMER_MAX_KEY      0x7FFFFFFFFFFFFFFFLL    /* signed */
127#define HAMMER_MIN_OBJID    HAMMER_MIN_KEY      /* signed */
128#define HAMMER_MAX_OBJID    HAMMER_MAX_KEY      /* signed */
129#define HAMMER_MIN_RECTYPE  0x0U            /* unsigned */
130#define HAMMER_MAX_RECTYPE  0xFFFFU         /* unsigned */
131#define HAMMER_MIN_OFFSET   0ULL            /* unsigned */
132#define HAMMER_MAX_OFFSET   0xFFFFFFFFFFFFFFFFULL   /* unsigned */
133
134/*
135 * hammer_off_t has several different encodings.  Note that not all zones
136 * encode a vol_no.  Zone bits are not a part of filesystem capacity as
137 * the zone bits aren't directly or indirectly mapped to physical volumes.
138 *
139 * In other words, HAMMER's logical filesystem offset consists of 64 bits,
140 * but the filesystem is considered 60 bits filesystem, not 64 bits.
141 * The maximum filesystem capacity is 1EB, not 16EB.
142 *
143 * zone 0:      available, a big-block that contains the offset is unused
144 * zone 1 (z,v,o):  raw volume relative (offset 0 is the volume header)
145 * zone 2 (z,v,o):  raw buffer relative (offset 0 is the first buffer)
146 * zone 3 (z,o):    undo/redo fifo  - fixed zone-2 offset array in volume header
147 * zone 4 (z,v,o):  freemap     - only real blockmap
148 * zone 8 (z,v,o):  B-Tree      - actually zone-2 address
149 * zone 9 (z,v,o):  meta        - actually zone-2 address
150 * zone 10 (z,v,o): large-data  - actually zone-2 address
151 * zone 11 (z,v,o): small-data  - actually zone-2 address
152 * zone 15:     unavailable, usually the offset is beyond volume size
153 *
154 * layer1/layer2 direct map:
155 *       Maximum HAMMER filesystem capacity from volume aspect
156 *       2^8(max volumes) * 2^52(max volume size) = 2^60 = 1EB (long offset)
157 *      <------------------------------------------------------------->
158 *       8bits   52bits (short offset)
159 *      <------><----------------------------------------------------->
160 *  zzzzvvvvvvvvoooo oooooooooooooooo oooooooooooooooo oooooooooooooooo
161 *  ----111111111111 1111112222222222 222222222ooooooo oooooooooooooooo
162 *      <-----------------><------------------><---------------------->
163 *       18bits             19bits              23bits
164 *      <------------------------------------------------------------->
165 *       2^18(layer1) * 2^19(layer2) * 2^23(big-block) = 2^60 = 1EB
166 *       Maximum HAMMER filesystem capacity from blockmap aspect
167 *
168 * volume#0 layout
169 *  +-------------------------> offset 0 of a device/partition
170 *  | volume header (1928 bytes)
171 *  | the rest of header junk space (HAMMER_BUFSIZE aligned)
172 *  +-------------------------> vol_bot_beg
173 *  | boot area (HAMMER_BUFSIZE aligned)
174 *  +-------------------------> vol_mem_beg
175 *  | memory log (HAMMER_BUFSIZE aligned)
176 *  +-------------------------> vol_buf_beg (physical offset of zone-2)
177 *  | zone-4 big-block for layer1
178 *  +-------------------------> vol_buf_beg + HAMMER_BIGBLOCK_SIZE
179 *  | zone-4 big-blocks for layer2
180 *  | ... (1 big-block per 4TB space)
181 *  +-------------------------> vol_buf_beg + HAMMER_BIGBLOCK_SIZE * ...
182 *  | zone-3 big-blocks for UNDO/REDO FIFO
183 *  | ... (max 128 big-blocks)
184 *  +-------------------------> vol_buf_beg + HAMMER_BIGBLOCK_SIZE * ...
185 *  | zone-8 big-block for root B-Tree node/etc
186 *  +-------------------------> vol_buf_beg + HAMMER_BIGBLOCK_SIZE * ...
187 *  | zone-9 big-block for root inode/PFS/etc
188 *  +-------------------------> vol_buf_beg + HAMMER_BIGBLOCK_SIZE * ...
189 *  | zone-X big-blocks
190 *  | ... (big-blocks for new zones after newfs_hammer)
191 *  | ...
192 *  | ...
193 *  | ...
194 *  | ...
195 *  +-------------------------> vol_buf_end (HAMMER_BUFSIZE aligned)
196 *  +-------------------------> end of a device/partition
197 *
198 * volume#N layout (0<N<256)
199 *  +-------------------------> offset 0 of a device/partition
200 *  | volume header (1928 bytes)
201 *  | the rest of header junk space (HAMMER_BUFSIZE aligned)
202 *  +-------------------------> vol_bot_beg
203 *  | boot area (HAMMER_BUFSIZE aligned)
204 *  +-------------------------> vol_mem_beg
205 *  | memory log (HAMMER_BUFSIZE aligned)
206 *  +-------------------------> vol_buf_beg (physical offset of zone-2)
207 *  | zone-4 big-blocks for layer2
208 *  | ... (1 big-block per 4TB space)
209 *  +-------------------------> vol_buf_beg + HAMMER_BIGBLOCK_SIZE * ...
210 *  | zone-X big-blocks
211 *  | ... (unused until volume#(N-1) runs out of space)
212 *  | ...
213 *  | ...
214 *  | ...
215 *  | ...
216 *  +-------------------------> vol_buf_end (HAMMER_BUFSIZE aligned)
217 *  +-------------------------> end of a device/partition
218 */
219
220#define HAMMER_ZONE_RAW_VOLUME      0x1000000000000000ULL
221#define HAMMER_ZONE_RAW_BUFFER      0x2000000000000000ULL
222#define HAMMER_ZONE_UNDO        0x3000000000000000ULL
223#define HAMMER_ZONE_FREEMAP     0x4000000000000000ULL
224#define HAMMER_ZONE_RESERVED05      0x5000000000000000ULL  /* not used */
225#define HAMMER_ZONE_RESERVED06      0x6000000000000000ULL  /* not used */
226#define HAMMER_ZONE_RESERVED07      0x7000000000000000ULL  /* not used */
227#define HAMMER_ZONE_BTREE       0x8000000000000000ULL
228#define HAMMER_ZONE_META        0x9000000000000000ULL
229#define HAMMER_ZONE_LARGE_DATA      0xA000000000000000ULL
230#define HAMMER_ZONE_SMALL_DATA      0xB000000000000000ULL
231#define HAMMER_ZONE_RESERVED0C      0xC000000000000000ULL  /* not used */
232#define HAMMER_ZONE_RESERVED0D      0xD000000000000000ULL  /* not used */
233#define HAMMER_ZONE_RESERVED0E      0xE000000000000000ULL  /* not used */
234#define HAMMER_ZONE_UNAVAIL     0xF000000000000000ULL
235
236#define HAMMER_ZONE_RAW_VOLUME_INDEX    1
237#define HAMMER_ZONE_RAW_BUFFER_INDEX    2
238#define HAMMER_ZONE_UNDO_INDEX      3
239#define HAMMER_ZONE_FREEMAP_INDEX   4
240#define HAMMER_ZONE_BTREE_INDEX     8
241#define HAMMER_ZONE_META_INDEX      9
242#define HAMMER_ZONE_LARGE_DATA_INDEX    10
243#define HAMMER_ZONE_SMALL_DATA_INDEX    11
244#define HAMMER_ZONE_UNAVAIL_INDEX   15
245
246#define HAMMER_MAX_ZONES        16
247
248#define HAMMER_ZONE(offset)     ((offset) & HAMMER_OFF_ZONE_MASK)
249
250#define hammer_is_zone_raw_volume(offset)       \
251    (HAMMER_ZONE(offset) == HAMMER_ZONE_RAW_VOLUME)
252#define hammer_is_zone_raw_buffer(offset)       \
253    (HAMMER_ZONE(offset) == HAMMER_ZONE_RAW_BUFFER)
254#define hammer_is_zone_undo(offset)         \
255    (HAMMER_ZONE(offset) == HAMMER_ZONE_UNDO)
256#define hammer_is_zone_freemap(offset)          \
257    (HAMMER_ZONE(offset) == HAMMER_ZONE_FREEMAP)
258#define hammer_is_zone_btree(offset)            \
259    (HAMMER_ZONE(offset) == HAMMER_ZONE_BTREE)
260#define hammer_is_zone_meta(offset)         \
261    (HAMMER_ZONE(offset) == HAMMER_ZONE_META)
262#define hammer_is_zone_large_data(offset)       \
263    (HAMMER_ZONE(offset) == HAMMER_ZONE_LARGE_DATA)
264#define hammer_is_zone_small_data(offset)       \
265    (HAMMER_ZONE(offset) == HAMMER_ZONE_SMALL_DATA)
266#define hammer_is_zone_unavail(offset)          \
267    (HAMMER_ZONE(offset) == HAMMER_ZONE_UNAVAIL)
268#define hammer_is_zone_data(offset)         \
269    (hammer_is_zone_large_data(offset) || hammer_is_zone_small_data(offset))
270
271#define hammer_is_index_record(zone)            \
272    ((zone) >= HAMMER_ZONE_BTREE_INDEX &&       \
273     (zone) < HAMMER_MAX_ZONES)
274
275#define hammer_is_zone_record(offset)           \
276    hammer_is_index_record(HAMMER_ZONE_DECODE(offset))
277
278#define hammer_is_index_direct_xlated(zone)     \
279    (((zone) == HAMMER_ZONE_RAW_BUFFER_INDEX) ||    \
280     ((zone) == HAMMER_ZONE_FREEMAP_INDEX) ||   \
281     hammer_is_index_record(zone))
282
283#define hammer_is_zone_direct_xlated(offset)        \
284    hammer_is_index_direct_xlated(HAMMER_ZONE_DECODE(offset))
285
286#define HAMMER_ZONE_ENCODE(zone, ham_off)       \
287    (((hammer_off_t)(zone) << 60) | (ham_off))
288#define HAMMER_ZONE_DECODE(ham_off)         \
289    ((int)(((hammer_off_t)(ham_off) >> 60)))
290
291#define HAMMER_VOL_ENCODE(vol_no)           \
292    ((hammer_off_t)((vol_no) & 255) << 52)
293#define HAMMER_VOL_DECODE(ham_off)          \
294    ((int)(((hammer_off_t)(ham_off) >> 52) & 255))
295
296#define HAMMER_OFF_SHORT_ENCODE(offset)         \
297    ((hammer_off_t)(offset) & HAMMER_OFF_SHORT_MASK)
298#define HAMMER_OFF_LONG_ENCODE(offset)          \
299    ((hammer_off_t)(offset) & HAMMER_OFF_LONG_MASK)
300
301#define HAMMER_ENCODE(zone, vol_no, offset)     \
302    (((hammer_off_t)(zone) << 60) |         \
303    HAMMER_VOL_ENCODE(vol_no) |         \
304    HAMMER_OFF_SHORT_ENCODE(offset))
305#define HAMMER_ENCODE_RAW_VOLUME(vol_no, offset)    \
306    HAMMER_ENCODE(HAMMER_ZONE_RAW_VOLUME_INDEX, vol_no, offset)
307#define HAMMER_ENCODE_RAW_BUFFER(vol_no, offset)    \
308    HAMMER_ENCODE(HAMMER_ZONE_RAW_BUFFER_INDEX, vol_no, offset)
309#define HAMMER_ENCODE_UNDO(offset)          \
310    HAMMER_ENCODE(HAMMER_ZONE_UNDO_INDEX, HAMMER_ROOT_VOLNO, offset)
311#define HAMMER_ENCODE_FREEMAP(vol_no, offset)       \
312    HAMMER_ENCODE(HAMMER_ZONE_FREEMAP_INDEX, vol_no, offset)
313
314/*
315 * Translate a zone address to zone-X address.
316 */
317#define hammer_xlate_to_zoneX(zone, offset)     \
318    HAMMER_ZONE_ENCODE((zone), (offset) & ~HAMMER_OFF_ZONE_MASK)
319#define hammer_xlate_to_zone2(offset)           \
320    hammer_xlate_to_zoneX(HAMMER_ZONE_RAW_BUFFER_INDEX, (offset))
321
322#define hammer_data_zone(data_len)          \
323    (((data_len) >= HAMMER_BUFSIZE) ?       \
324     HAMMER_ZONE_LARGE_DATA :           \
325     HAMMER_ZONE_SMALL_DATA)
326#define hammer_data_zone_index(data_len)        \
327    (((data_len) >= HAMMER_BUFSIZE) ?       \
328     HAMMER_ZONE_LARGE_DATA_INDEX :         \
329     HAMMER_ZONE_SMALL_DATA_INDEX)
330
331/*
332 * Big-Block backing store
333 *
334 * A blockmap is a two-level map which translates a blockmap-backed zone
335 * offset into a raw zone 2 offset.  The layer 1 handles 18 bits and the
336 * layer 2 handles 19 bits.  The 8M big-block size is 23 bits so two
337 * layers gives us 18+19+23 = 60 bits of address space.
338 *
339 * When using hinting for a blockmap lookup, the hint is lost when the
340 * scan leaves the HINTBLOCK, which is typically several BIGBLOCK's.
341 * HINTBLOCK is a heuristic.
342 */
343#define HAMMER_HINTBLOCK_SIZE       (HAMMER_BIGBLOCK_SIZE * 4)
344#define HAMMER_HINTBLOCK_MASK64     ((uint64_t)HAMMER_HINTBLOCK_SIZE - 1)
345#define HAMMER_BIGBLOCK_SIZE        (8192 * 1024)
346#define HAMMER_BIGBLOCK_SIZE64      ((uint64_t)HAMMER_BIGBLOCK_SIZE)
347#define HAMMER_BIGBLOCK_MASK        (HAMMER_BIGBLOCK_SIZE - 1)
348#define HAMMER_BIGBLOCK_MASK64      ((uint64_t)HAMMER_BIGBLOCK_SIZE - 1)
349#define HAMMER_BIGBLOCK_BITS        23
350#if 0
351#define HAMMER_BIGBLOCK_OVERFILL    (6144 * 1024)
352#endif
353#if (1 << HAMMER_BIGBLOCK_BITS) != HAMMER_BIGBLOCK_SIZE
354#error "HAMMER_BIGBLOCK_BITS BROKEN"
355#endif
356
357#define HAMMER_BUFFERS_PER_BIGBLOCK         \
358    (HAMMER_BIGBLOCK_SIZE / HAMMER_BUFSIZE)
359#define HAMMER_BUFFERS_PER_BIGBLOCK_MASK        \
360    (HAMMER_BUFFERS_PER_BIGBLOCK - 1)
361#define HAMMER_BUFFERS_PER_BIGBLOCK_MASK64      \
362    ((hammer_off_t)HAMMER_BUFFERS_PER_BIGBLOCK_MASK)
363
364#define HAMMER_BIGBLOCK_DOALIGN(offset)             \
365    (((offset) + HAMMER_BIGBLOCK_MASK64) & ~HAMMER_BIGBLOCK_MASK64)
366
367/*
368 * Maximum number of mirrors operating in master mode (multi-master
369 * clustering and mirroring). Note that HAMMER1 does not support
370 * multi-master clustering as of 2015.
371 */
372#define HAMMER_MAX_MASTERS      16
373
374/*
375 * The blockmap is somewhat of a degenerate structure.  HAMMER only actually
376 * uses it in its original incarnation to implement the freemap.
377 *
378 * zone:1   raw volume (no blockmap)
379 * zone:2   raw buffer (no blockmap)
380 * zone:3   undomap    (direct layer2 array in volume header)
381 * zone:4   freemap    (the only real blockmap)
382 * zone:8-15    zone id used to classify big-block only, address is actually
383 *      a zone-2 address.
384 */
385typedef struct hammer_blockmap {
386    hammer_off_t    phys_offset;  /* zone-2 offset only used by zone-4 */
387    hammer_off_t    first_offset; /* zone-X offset only used by zone-3 */
388    hammer_off_t    next_offset;  /* zone-X offset for allocation */
389    hammer_off_t    alloc_offset; /* zone-X offset only used by zone-3 */
390    uint32_t    reserved01;
391    hammer_crc_t    entry_crc;
392} *hammer_blockmap_t;
393
394#define HAMMER_BLOCKMAP_CRCSIZE \
395    offsetof(struct hammer_blockmap, entry_crc)
396
397/*
398 * The blockmap is a 2-layer entity made up of big-blocks.  The first layer
399 * contains 262144 32-byte entries (18 bits), the second layer contains
400 * 524288 16-byte entries (19 bits), representing 8MB (23 bit) blockmaps.
401 * 18+19+23 = 60 bits.  The top four bits are the zone id.
402 *
403 * Currently only the freemap utilizes both layers in all their glory.
404 * All primary data/meta-data zones actually encode a zone-2 address
405 * requiring no real blockmap translation.
406 *
407 * The freemap uses the upper 8 bits of layer-1 to identify the volume,
408 * thus any space allocated via the freemap can be directly translated
409 * to a zone:2 (or zone:8-15) address.
410 *
411 * zone-X blockmap offset: [zone:4][layer1:18][layer2:19][big-block:23]
412 */
413
414/*
415 * 32 bytes layer1 entry for 8MB big-block.
416 * A big-block can hold 2^23 / 2^5 = 2^18 layer1 entries,
417 * which equals bits assigned for layer1 in zone-2 address.
418 */
419typedef struct hammer_blockmap_layer1 {
420    hammer_off_t    blocks_free;    /* big-blocks free */
421    hammer_off_t    phys_offset;    /* UNAVAIL or zone-2 */
422    hammer_off_t    reserved01;
423    hammer_crc_t    layer2_crc; /* xor'd crc's of HAMMER_BLOCKSIZE */
424                    /* (not yet used) */
425    hammer_crc_t    layer1_crc; /* MUST BE LAST FIELD OF STRUCTURE*/
426} *hammer_blockmap_layer1_t;
427
428#define HAMMER_LAYER1_CRCSIZE   \
429    offsetof(struct hammer_blockmap_layer1, layer1_crc)
430
431/*
432 * 16 bytes layer2 entry for 8MB big-blocks.
433 * A big-block can hold 2^23 / 2^4 = 2^19 layer2 entries,
434 * which equals bits assigned for layer2 in zone-2 address.
435 *
436 * NOTE: bytes_free is signed and can legally go negative if/when data
437 *   de-dup occurs.  This field will never go higher than
438 *   HAMMER_BIGBLOCK_SIZE.  If exactly HAMMER_BIGBLOCK_SIZE
439 *   the big-block is completely free.
440 */
441typedef struct hammer_blockmap_layer2 {
442    uint8_t     zone;       /* typed allocation zone */
443    uint8_t     reserved01;
444    uint16_t    reserved02;
445    uint32_t    append_off; /* allocatable space index */
446    int32_t     bytes_free; /* bytes free within this big-block */
447    hammer_crc_t    entry_crc;
448} *hammer_blockmap_layer2_t;
449
450#define HAMMER_LAYER2_CRCSIZE   \
451    offsetof(struct hammer_blockmap_layer2, entry_crc)
452
453#define HAMMER_BLOCKMAP_UNAVAIL ((hammer_off_t)-1LL)
454
455#define HAMMER_BLOCKMAP_RADIX1  /* 2^18 = 262144 */ \
456    ((int)(HAMMER_BIGBLOCK_SIZE / sizeof(struct hammer_blockmap_layer1)))
457#define HAMMER_BLOCKMAP_RADIX2  /* 2^19 = 524288 */ \
458    ((int)(HAMMER_BIGBLOCK_SIZE / sizeof(struct hammer_blockmap_layer2)))
459
460#define HAMMER_BLOCKMAP_LAYER1  /* 2^(18+19+23) = 1EB */    \
461    (HAMMER_BLOCKMAP_RADIX1 * HAMMER_BLOCKMAP_LAYER2)
462#define HAMMER_BLOCKMAP_LAYER2  /* 2^(19+23) = 4TB */       \
463    (HAMMER_BLOCKMAP_RADIX2 * HAMMER_BIGBLOCK_SIZE64)
464
465#define HAMMER_BLOCKMAP_LAYER1_MASK (HAMMER_BLOCKMAP_LAYER1 - 1)
466#define HAMMER_BLOCKMAP_LAYER2_MASK (HAMMER_BLOCKMAP_LAYER2 - 1)
467
468#define HAMMER_BLOCKMAP_LAYER2_DOALIGN(offset)          \
469    (((offset) + HAMMER_BLOCKMAP_LAYER2_MASK) &     \
470     ~HAMMER_BLOCKMAP_LAYER2_MASK)
471
472/*
473 * Index within layer1 or layer2 big-block for the entry representing
474 * a zone-2 physical offset.
475 */
476#define HAMMER_BLOCKMAP_LAYER1_INDEX(zone2_offset)      \
477    ((int)(((zone2_offset) & HAMMER_BLOCKMAP_LAYER1_MASK) / \
478     HAMMER_BLOCKMAP_LAYER2))
479
480#define HAMMER_BLOCKMAP_LAYER2_INDEX(zone2_offset)      \
481    ((int)(((zone2_offset) & HAMMER_BLOCKMAP_LAYER2_MASK) / \
482    HAMMER_BIGBLOCK_SIZE64))
483
484/*
485 * Byte offset within layer1 or layer2 big-block for the entry representing
486 * a zone-2 physical offset.  Multiply the index by sizeof(blockmap_layer).
487 */
488#define HAMMER_BLOCKMAP_LAYER1_OFFSET(zone2_offset)     \
489    (HAMMER_BLOCKMAP_LAYER1_INDEX(zone2_offset) *       \
490     sizeof(struct hammer_blockmap_layer1))
491
492#define HAMMER_BLOCKMAP_LAYER2_OFFSET(zone2_offset)     \
493    (HAMMER_BLOCKMAP_LAYER2_INDEX(zone2_offset) *       \
494     sizeof(struct hammer_blockmap_layer2))
495
496/*
497 * Move on to offset 0 of the next layer1 or layer2.
498 */
499#define HAMMER_ZONE_LAYER1_NEXT_OFFSET(offset)          \
500    (((offset) + HAMMER_BLOCKMAP_LAYER2) & ~HAMMER_BLOCKMAP_LAYER2_MASK)
501
502#define HAMMER_ZONE_LAYER2_NEXT_OFFSET(offset)          \
503    (((offset) + HAMMER_BIGBLOCK_SIZE) & ~HAMMER_BIGBLOCK_MASK64)
504
505/*
506 * HAMMER UNDO parameters.  The UNDO fifo is mapped directly in the volume
507 * header with an array of zone-2 offsets.  A maximum of (128x8MB) = 1GB,
508 * and minimum of (64x8MB) = 512MB may be reserved.  The size of the undo
509 * fifo is usually set a newfs time.
510 */
511#define HAMMER_MIN_UNDO_BIGBLOCKS       64
512#define HAMMER_MAX_UNDO_BIGBLOCKS       128
513
514/*
515 * All on-disk HAMMER structures which make up elements of the UNDO FIFO
516 * contain a hammer_fifo_head and hammer_fifo_tail structure.  This structure
517 * contains all the information required to validate the fifo element
518 * and to scan the fifo in either direction.  The head is typically embedded
519 * in higher level hammer on-disk structures while the tail is typically
520 * out-of-band.  hdr_size is the size of the whole mess, including the tail.
521 *
522 * All undo structures are guaranteed to not cross a 16K filesystem
523 * buffer boundary.  Most undo structures are fairly small.  Data spaces
524 * are not immediately reused by HAMMER so file data is not usually recorded
525 * as part of an UNDO.
526 *
527 * PAD elements are allowed to take up only 8 bytes of space as a special
528 * case, containing only hdr_signature, hdr_type, and hdr_size fields,
529 * and with the tail overloaded onto the head structure for 8 bytes total.
530 *
531 * Every undo record has a sequence number.  This number is unrelated to
532 * transaction ids and instead collects the undo transactions associated
533 * with a single atomic operation.  A larger transactional operation, such
534 * as a remove(), may consist of several smaller atomic operations
535 * representing raw meta-data operations.
536 *
537 *              HAMMER VERSION 4 CHANGES
538 *
539 * In HAMMER version 4 the undo structure alignment is reduced from 16384
540 * to 512 bytes in order to ensure that each 512 byte sector begins with
541 * a header.  The hdr_seq field in the header is a 32 bit sequence number
542 * which allows the recovery code to detect missing sectors
543 * without relying on the 32-bit crc and to definitively identify the current
544 * undo sequence space without having to rely on information from the volume
545 * header.  In addition, new REDO entries in the undo space are used to
546 * record write, write/extend, and transaction id updates.
547 *
548 * The grand result is:
549 *
550 * (1) The volume header no longer needs to be synchronized for most
551 *     flush and fsync operations.
552 *
553 * (2) Most fsync operations need only lay down REDO records
554 *
555 * (3) Data overwrite for nohistory operations covered by REDO records
556 *     can be supported (instead of rolling a new block allocation),
557 *     by rolling UNDO for the prior contents of the data.
558 *
559 *              HAMMER VERSION 5 CHANGES
560 *
561 * Hammer version 5 contains a minor adjustment making layer2's bytes_free
562 * field signed, allowing dedup to push it into the negative domain.
563 */
564#define HAMMER_HEAD_ALIGN       8
565#define HAMMER_HEAD_ALIGN_MASK      (HAMMER_HEAD_ALIGN - 1)
566#define HAMMER_HEAD_DOALIGN(bytes)  \
567    (((bytes) + HAMMER_HEAD_ALIGN_MASK) & ~HAMMER_HEAD_ALIGN_MASK)
568
569#define HAMMER_UNDO_ALIGN       512
570#define HAMMER_UNDO_ALIGN64     ((uint64_t)512)
571#define HAMMER_UNDO_MASK        (HAMMER_UNDO_ALIGN - 1)
572#define HAMMER_UNDO_MASK64      (HAMMER_UNDO_ALIGN64 - 1)
573#define HAMMER_UNDO_DOALIGN(offset) \
574    (((offset) + HAMMER_UNDO_MASK) & ~HAMMER_UNDO_MASK64)
575
576typedef struct hammer_fifo_head {
577    uint16_t hdr_signature;
578    uint16_t hdr_type;
579    uint32_t hdr_size;  /* Aligned size of the whole mess */
580    uint32_t hdr_seq;   /* Sequence number */
581    hammer_crc_t hdr_crc;   /* XOR crc up to field w/ crc after field */
582} *hammer_fifo_head_t;
583
584#define HAMMER_FIFO_HEAD_CRCOFF offsetof(struct hammer_fifo_head, hdr_crc)
585
586typedef struct hammer_fifo_tail {
587    uint16_t tail_signature;
588    uint16_t tail_type;
589    uint32_t tail_size; /* aligned size of the whole mess */
590} *hammer_fifo_tail_t;
591
592/*
593 * Fifo header types.
594 *
595 * NOTE: 0x8000U part of HAMMER_HEAD_TYPE_PAD can be removed if the HAMMER
596 * version ever gets bumped again. It exists only to keep compatibility with
597 * older versions.
598 */
599#define HAMMER_HEAD_TYPE_PAD    (0x0040U | 0x8000U)
600#define HAMMER_HEAD_TYPE_DUMMY  0x0041U     /* dummy entry w/seqno */
601#define HAMMER_HEAD_TYPE_UNDO   0x0043U     /* random UNDO information */
602#define HAMMER_HEAD_TYPE_REDO   0x0044U     /* data REDO / fast fsync */
603
604#define HAMMER_HEAD_SIGNATURE   0xC84EU
605#define HAMMER_TAIL_SIGNATURE   0xC74FU
606
607/*
608 * Misc FIFO structures.
609 *
610 * UNDO - Raw meta-data media updates.
611 */
612typedef struct hammer_fifo_undo {
613    struct hammer_fifo_head head;
614    hammer_off_t        undo_offset;    /* zone-1,2 offset */
615    int32_t         undo_data_bytes;
616    int32_t         undo_reserved01;
617    /* followed by data */
618} *hammer_fifo_undo_t;
619
620/*
621 * REDO (HAMMER version 4+) - Logical file writes/truncates.
622 *
623 * REDOs contain information which will be duplicated in a later meta-data
624 * update, allowing fast write()+fsync() operations.  REDOs can be ignored
625 * without harming filesystem integrity but must be processed if fsync()
626 * semantics are desired.
627 *
628 * Unlike UNDOs which are processed backwards within the recovery span,
629 * REDOs must be processed forwards starting further back (starting outside
630 * the recovery span).
631 *
632 *  WRITE   - Write logical file (with payload).  Executed both
633 *        out-of-span and in-span.  Out-of-span WRITEs may be
634 *        filtered out by TERMs.
635 *
636 *  TRUNC   - Truncate logical file (no payload).  Executed both
637 *        out-of-span and in-span.  Out-of-span WRITEs may be
638 *        filtered out by TERMs.
639 *
640 *  TERM_*  - Indicates meta-data was committed (if out-of-span) or
641 *        will be rolled-back (in-span).  Any out-of-span TERMs
642 *        matching earlier WRITEs remove those WRITEs from
643 *        consideration as they might conflict with a later data
644 *        commit (which is not being rolled-back).
645 *
646 *  SYNC    - The earliest in-span SYNC (the last one when scanning
647 *        backwards) tells the recovery code how far out-of-span
648 *        it must go to run REDOs.
649 *
650 * NOTE: WRITEs do not always have matching TERMs even under
651 *   perfect conditions because truncations might remove the
652 *   buffers from consideration.  I/O problems can also remove
653 *   buffers from consideration.
654 *
655 *   TRUNCSs do not always have matching TERMs because several
656 *   truncations may be aggregated together into a single TERM.
657 */
658typedef struct hammer_fifo_redo {
659    struct hammer_fifo_head head;
660    int64_t         redo_objid; /* file being written */
661    hammer_off_t        redo_offset;    /* logical offset in file */
662    int32_t         redo_data_bytes;
663    uint32_t        redo_flags;
664    uint32_t        redo_localization;
665    uint32_t        redo_reserved01;
666    uint64_t        redo_reserved02;
667    /* followed by data */
668} *hammer_fifo_redo_t;
669
670#define HAMMER_REDO_WRITE   0x00000001
671#define HAMMER_REDO_TRUNC   0x00000002
672#define HAMMER_REDO_TERM_WRITE  0x00000004
673#define HAMMER_REDO_TERM_TRUNC  0x00000008
674#define HAMMER_REDO_SYNC    0x00000010
675
676typedef union hammer_fifo_any {
677    struct hammer_fifo_head head;
678    struct hammer_fifo_undo undo;
679    struct hammer_fifo_redo redo;
680} *hammer_fifo_any_t;
681
682/*
683 * Volume header types
684 */
685#define HAMMER_FSBUF_VOLUME 0xC8414D4DC5523031ULL   /* HAMMER01 */
686#define HAMMER_FSBUF_VOLUME_REV 0x313052C54D4D41C8ULL   /* (reverse endian) */
687
688/*
689 * HAMMER Volume header
690 *
691 * A HAMMER filesystem can be built from 1-256 block devices, each block
692 * device contains a volume header followed by however many buffers fit
693 * into the volume.
694 *
695 * One of the volumes making up a HAMMER filesystem is the root volume.
696 * The root volume is always volume #0 which is the first block device path
697 * specified by newfs_hammer(8).  All HAMMER volumes have a volume header,
698 * however the root volume may be the only volume that has valid values for
699 * some fields in the header.
700 *
701 * Special field notes:
702 *
703 *  vol_bot_beg - offset of boot area (mem_beg - bot_beg bytes)
704 *  vol_mem_beg - offset of memory log (buf_beg - mem_beg bytes)
705 *  vol_buf_beg - offset of the first buffer in volume
706 *  vol_buf_end - offset of volume EOF (on buffer boundary)
707 *
708 *  The memory log area allows a kernel to cache new records and data
709 *  in memory without allocating space in the actual filesystem to hold
710 *  the records and data.  In the event that a filesystem becomes full,
711 *  any records remaining in memory can be flushed to the memory log
712 *  area.  This allows the kernel to immediately return success.
713 *
714 *  The buffer offset is a physical offset of zone-2 offset. The lower
715 *  52 bits of the zone-2 offset is added to the buffer offset of each
716 *  volume to generate an actual I/O offset within the block device.
717 *
718 *  NOTE: boot area and memory log are currently not used.
719 */
720
721/*
722 * Filesystem type string
723 */
724#define HAMMER_FSTYPE_STRING        "DragonFly HAMMER"
725
726/*
727 * These macros are only used by userspace when userspace commands either
728 * initialize or add a new HAMMER volume.
729 */
730#define HAMMER_BOOT_MINBYTES        (32*1024)
731#define HAMMER_BOOT_NOMBYTES        (64LL*1024*1024)
732#define HAMMER_BOOT_MAXBYTES        (256LL*1024*1024)
733
734#define HAMMER_MEM_MINBYTES     (256*1024)
735#define HAMMER_MEM_NOMBYTES     (1LL*1024*1024*1024)
736#define HAMMER_MEM_MAXBYTES     (64LL*1024*1024*1024)
737
738typedef struct hammer_volume_ondisk {
739    uint64_t vol_signature; /* HAMMER_FSBUF_VOLUME for a valid header */
740
741    /*
742     * These are relative to block device offset, not zone offsets.
743     */
744    int64_t vol_bot_beg;    /* offset of boot area */
745    int64_t vol_mem_beg;    /* offset of memory log */
746    int64_t vol_buf_beg;    /* offset of the first buffer in volume */
747    int64_t vol_buf_end;    /* offset of volume EOF (on buffer boundary) */
748    int64_t vol_reserved01;
749
750    hammer_uuid_t vol_fsid; /* identify filesystem */
751    hammer_uuid_t vol_fstype; /* identify filesystem type */
752    char vol_label[64]; /* filesystem label */
753
754    int32_t vol_no;     /* volume number within filesystem */
755    int32_t vol_count;  /* number of volumes making up filesystem */
756
757    uint32_t vol_version;   /* version control information */
758    hammer_crc_t vol_crc;   /* header crc */
759    uint32_t vol_flags; /* volume flags */
760    uint32_t vol_rootvol;   /* the root volume number (must be 0) */
761
762    uint32_t vol_reserved[8];
763
764    /*
765     * These fields are initialized and space is reserved in every
766     * volume making up a HAMMER filesytem, but only the root volume
767     * contains valid data.  Note that vol0_stat_bigblocks does not
768     * include big-blocks for freemap and undomap initially allocated
769     * by newfs_hammer(8).
770     */
771    int64_t vol0_stat_bigblocks;    /* total big-blocks when fs is empty */
772    int64_t vol0_stat_freebigblocks;/* number of free big-blocks */
773    int64_t vol0_reserved01;
774    int64_t vol0_stat_inodes;   /* for statfs only */
775    int64_t vol0_reserved02;
776    hammer_off_t vol0_btree_root;   /* B-Tree root offset in zone-8 */
777    hammer_tid_t vol0_next_tid; /* highest partially synchronized TID */
778    hammer_off_t vol0_reserved03;
779
780    /*
781     * Blockmaps for zones.  Not all zones use a blockmap.  Note that
782     * the entire root blockmap is cached in the hammer_mount structure.
783     */
784    struct hammer_blockmap  vol0_blockmap[HAMMER_MAX_ZONES];
785
786    /*
787     * Array of zone-2 addresses for undo FIFO.
788     */
789    hammer_off_t        vol0_undo_array[HAMMER_MAX_UNDO_BIGBLOCKS];
790} *hammer_volume_ondisk_t;
791
792#define HAMMER_ROOT_VOLNO       0
793
794#define HAMMER_VOLF_NEEDFLUSH       0x0004  /* volume needs flush */
795
796#define HAMMER_VOL_CRCSIZE1 \
797    offsetof(struct hammer_volume_ondisk, vol_crc)
798#define HAMMER_VOL_CRCSIZE2 \
799    (sizeof(struct hammer_volume_ondisk) - HAMMER_VOL_CRCSIZE1 -    \
800     sizeof(hammer_crc_t))
801
802#define HAMMER_VOL_VERSION_MIN      1   /* minimum supported version */
803#define HAMMER_VOL_VERSION_DEFAULT  7   /* newfs default version */
804#define HAMMER_VOL_VERSION_WIP      8   /* version >= this is WIP */
805#define HAMMER_VOL_VERSION_MAX      7   /* maximum supported version */
806
807#define HAMMER_VOL_VERSION_ONE      1
808#define HAMMER_VOL_VERSION_TWO      2   /* new dirent layout (2.3+) */
809#define HAMMER_VOL_VERSION_THREE    3   /* new snapshot layout (2.5+) */
810#define HAMMER_VOL_VERSION_FOUR     4   /* new undo/flush (2.5+) */
811#define HAMMER_VOL_VERSION_FIVE     5   /* dedup (2.9+) */
812#define HAMMER_VOL_VERSION_SIX      6   /* DIRHASH_ALG1 */
813#define HAMMER_VOL_VERSION_SEVEN    7   /* use the faster iscsi_crc */
814
815/*
816 * Translate a zone-2 address to physical address
817 */
818#define hammer_xlate_to_phys(volume, zone2_offset)  \
819    ((volume)->vol_buf_beg + HAMMER_OFF_SHORT_ENCODE(zone2_offset))
820
821/*
822 * Translate a zone-3 address to zone-2 address
823 */
824#define HAMMER_UNDO_INDEX(zone3_offset)         \
825    (HAMMER_OFF_SHORT_ENCODE(zone3_offset) / HAMMER_BIGBLOCK_SIZE)
826
827#define hammer_xlate_to_undo(volume, zone3_offset)          \
828    ((volume)->vol0_undo_array[HAMMER_UNDO_INDEX(zone3_offset)] +   \
829     (zone3_offset & HAMMER_BIGBLOCK_MASK64))
830
831/*
832 * Effective per-volume filesystem capacity including big-blocks for layer1/2
833 */
834#define HAMMER_VOL_BUF_SIZE(volume)         \
835    ((volume)->vol_buf_end - (volume)->vol_buf_beg)
836
837/*
838 * Record types are fairly straightforward.  The B-Tree includes the record
839 * type in its index sort.
840 */
841#define HAMMER_RECTYPE_UNKNOWN      0x0000
842#define HAMMER_RECTYPE_INODE        0x0001  /* inode in obj_id space */
843#define HAMMER_RECTYPE_DATA     0x0010
844#define HAMMER_RECTYPE_DIRENTRY     0x0011
845#define HAMMER_RECTYPE_DB       0x0012
846#define HAMMER_RECTYPE_EXT      0x0013  /* ext attributes */
847#define HAMMER_RECTYPE_FIX      0x0014  /* fixed attribute */
848#define HAMMER_RECTYPE_PFS      0x0015  /* PFS management */
849#define HAMMER_RECTYPE_SNAPSHOT     0x0016  /* Snapshot management */
850#define HAMMER_RECTYPE_CONFIG       0x0017  /* hammer cleanup config */
851#define HAMMER_RECTYPE_MAX      0xFFFF
852
853#define HAMMER_RECTYPE_ENTRY_START  (HAMMER_RECTYPE_INODE + 1)
854#define HAMMER_RECTYPE_CLEAN_START  HAMMER_RECTYPE_EXT
855
856#define HAMMER_FIXKEY_SYMLINK       1
857
858#define HAMMER_OBJTYPE_UNKNOWN      0   /* never exists on-disk as unknown */
859#define HAMMER_OBJTYPE_DIRECTORY    1
860#define HAMMER_OBJTYPE_REGFILE      2
861#define HAMMER_OBJTYPE_DBFILE       3
862#define HAMMER_OBJTYPE_FIFO     4
863#define HAMMER_OBJTYPE_CDEV     5
864#define HAMMER_OBJTYPE_BDEV     6
865#define HAMMER_OBJTYPE_SOFTLINK     7
866#define HAMMER_OBJTYPE_PSEUDOFS     8   /* pseudo filesystem obj */
867#define HAMMER_OBJTYPE_SOCKET       9
868
869/*
870 * HAMMER inode attribute data
871 *
872 * The data reference for a HAMMER inode points to this structure.  Any
873 * modifications to the contents of this structure will result in a
874 * replacement operation.
875 *
876 * parent_obj_id is only valid for directories (which cannot be hard-linked),
877 * and specifies the parent directory obj_id.  This field will also be set
878 * for non-directory inodes as a recovery aid, but can wind up holding
879 * stale information.  However, since object id's are not reused, the worse
880 * that happens is that the recovery code is unable to use it.
881 * A parent_obj_id of 0 means it's a root inode of root or non-root PFS.
882 *
883 * NOTE: Future note on directory hardlinks.  We can implement a record type
884 * which allows us to point to multiple parent directories.
885 */
886typedef struct hammer_inode_data {
887    uint16_t version;   /* inode data version */
888    uint16_t mode;      /* basic unix permissions */
889    uint32_t uflags;    /* chflags */
890    uint32_t rmajor;    /* used by device nodes */
891    uint32_t rminor;    /* used by device nodes */
892    uint64_t ctime;
893    int64_t parent_obj_id;  /* parent directory obj_id */
894    hammer_uuid_t uid;
895    hammer_uuid_t gid;
896
897    uint8_t obj_type;
898    uint8_t cap_flags;  /* capability support flags (extension) */
899    uint16_t reserved01;
900    uint32_t reserved02;
901    uint64_t nlinks;    /* hard links */
902    uint64_t size;      /* filesystem object size */
903    union {
904        char    symlink[24];    /* HAMMER_INODE_BASESYMLEN */
905    } ext;
906    uint64_t mtime; /* mtime must be second-to-last */
907    uint64_t atime; /* atime must be last */
908} *hammer_inode_data_t;
909
910/*
911 * Neither mtime nor atime upates are CRCd by the B-Tree element.
912 * mtime updates have UNDO, atime updates do not.
913 */
914#define HAMMER_INODE_CRCSIZE    \
915    offsetof(struct hammer_inode_data, mtime)
916
917#define HAMMER_INODE_DATA_VERSION   1
918#define HAMMER_OBJID_ROOT       1   /* root inodes # */
919#define HAMMER_INODE_BASESYMLEN     24  /* see ext.symlink */
920
921/*
922 * Capability & implementation flags.
923 *
924 * HAMMER_INODE_CAP_DIR_LOCAL_INO - Use inode B-Tree localization
925 * for directory entries.  Also see HAMMER_DIR_INODE_LOCALIZATION().
926 */
927#define HAMMER_INODE_CAP_DIRHASH_MASK   0x03    /* directory: hash algorithm */
928#define HAMMER_INODE_CAP_DIRHASH_ALG0   0x00
929#define HAMMER_INODE_CAP_DIRHASH_ALG1   0x01
930#define HAMMER_INODE_CAP_DIRHASH_ALG2   0x02
931#define HAMMER_INODE_CAP_DIRHASH_ALG3   0x03
932#define HAMMER_INODE_CAP_DIR_LOCAL_INO  0x04    /* use inode localization */
933
934#define HAMMER_DATA_DOALIGN(offset)             \
935    (((offset) + 15) & ~15)
936#define HAMMER_DATA_DOALIGN_WITH(type, offset)          \
937    (((type)(offset) + 15) & (~(type)15))
938
939/*
940 * A HAMMER directory entry associates a HAMMER filesystem object with a
941 * namespace.  It is hooked into a pseudo-filesystem (with its own inode
942 * numbering space) in the filesystem by setting the high 16 bits of the
943 * localization field.  The low 16 bits must be 0 and are reserved for
944 * future use.
945 *
946 * Directory entries are indexed with a 128 bit namekey rather then an
947 * offset.  A portion of the namekey is an iterator/randomizer to deal
948 * with collisions.
949 *
950 * NOTE: leaf.base.obj_type from the related B-Tree leaf entry holds
951 * the filesystem object type of obj_id, e.g. a den_type equivalent.
952 * It is not stored in hammer_direntry_data.
953 *
954 * NOTE: name field / the filename data reference is NOT terminated with \0.
955 */
956typedef struct hammer_direntry_data {
957    int64_t obj_id;         /* object being referenced */
958    uint32_t localization;      /* identify pseudo-filesystem */
959    uint32_t reserved01;
960    char    name[16];       /* name (extended) */
961} *hammer_direntry_data_t;
962
963#define HAMMER_ENTRY_NAME_OFF   offsetof(struct hammer_direntry_data, name[0])
964#define HAMMER_ENTRY_SIZE(nlen) offsetof(struct hammer_direntry_data, name[nlen])
965
966/*
967 * Symlink data which does not fit in the inode is stored in a separate
968 * FIX type record.
969 */
970typedef struct hammer_symlink_data {
971    char    name[16];       /* name (extended) */
972} *hammer_symlink_data_t;
973
974#define HAMMER_SYMLINK_NAME_OFF offsetof(struct hammer_symlink_data, name[0])
975
976/*
977 * The root inode for the primary filesystem and root inode for any
978 * pseudo-fs may be tagged with an optional data structure using
979 * HAMMER_RECTYPE_PFS and localization id.  This structure allows
980 * the node to be used as a mirroring master or slave.
981 *
982 * When operating as a slave CD's into the node automatically become read-only
983 * and as-of sync_end_tid.
984 *
985 * When operating as a master the read PFSD info sets sync_end_tid to
986 * the most recently flushed TID.
987 *
988 * sync_low_tid is not yet used but will represent the highest pruning
989 * end-point, after which full history is available.
990 *
991 * We need to pack this structure making it equally sized on both 32-bit and
992 * 64-bit machines as it is part of struct hammer_ioc_mrecord_pfs which is
993 * send over the wire in hammer mirror operations. Only on 64-bit machines
994 * the size of this struct differ when packed or not. This leads us to the
995 * situation where old 64-bit systems (using the non-packed structure),
996 * which were never able to mirror to/from 32-bit systems, are now no longer
997 * able to mirror to/from newer 64-bit systems (using the packed structure).
998 */
999struct hammer_pseudofs_data {
1000    hammer_tid_t    sync_low_tid;   /* full history beyond this point */
1001    hammer_tid_t    sync_beg_tid;   /* earliest tid w/ full history avail */
1002    hammer_tid_t    sync_end_tid;   /* current synchronizatoin point */
1003    uint64_t    sync_beg_ts;    /* real-time of last completed sync */
1004    uint64_t    sync_end_ts;    /* initiation of current sync cycle */
1005    hammer_uuid_t   shared_uuid;    /* shared uuid (match required) */
1006    hammer_uuid_t   unique_uuid;    /* unique uuid of this master/slave */
1007    int32_t     reserved01; /* reserved for future master_id */
1008    int32_t     mirror_flags;   /* misc flags */
1009    char        label[64];  /* filesystem space label */
1010    char        snapshots[64];  /* softlink dir for pruning */
1011    int32_t     reserved02; /* was prune_{time,freq} */
1012    int32_t     reserved03; /* was reblock_{time,freq} */
1013    int32_t     reserved04; /* was snapshot_freq */
1014    int32_t     prune_min;  /* do not prune recent history */
1015    int32_t     prune_max;  /* do not retain history beyond here */
1016    int32_t     reserved[16];
1017} __packed;
1018
1019typedef struct hammer_pseudofs_data *hammer_pseudofs_data_t;
1020
1021#define HAMMER_PFSD_SLAVE   0x00000001
1022#define HAMMER_PFSD_DELETED 0x80000000
1023
1024#define hammer_is_pfs_slave(pfsd)           \
1025    (((pfsd)->mirror_flags & HAMMER_PFSD_SLAVE) != 0)
1026#define hammer_is_pfs_master(pfsd)          \
1027    (!hammer_is_pfs_slave(pfsd))
1028#define hammer_is_pfs_deleted(pfsd)         \
1029    (((pfsd)->mirror_flags & HAMMER_PFSD_DELETED) != 0)
1030
1031#define HAMMER_MAX_PFS      65536
1032#define HAMMER_MAX_PFSID    (HAMMER_MAX_PFS - 1)
1033#define HAMMER_ROOT_PFSID   0
1034
1035/*
1036 * Snapshot meta-data { Objid = HAMMER_OBJID_ROOT, Key = tid, rectype = SNAPSHOT }.
1037 *
1038 * Snapshot records replace the old <fs>/snapshots/<softlink> methodology.  Snapshot
1039 * records are mirrored but may be independantly managed once they are laid down on
1040 * a slave.
1041 *
1042 * NOTE: The b-tree key is signed, the tid is not, so callers must still sort the
1043 *   results.
1044 *
1045 * NOTE: Reserved fields must be zero (as usual)
1046 */
1047typedef struct hammer_snapshot_data {
1048    hammer_tid_t    tid;        /* the snapshot TID itself (== key) */
1049    uint64_t    ts;     /* real-time when snapshot was made */
1050    uint64_t    reserved01;
1051    uint64_t    reserved02;
1052    char        label[64];  /* user-supplied description */
1053    uint64_t    reserved03[4];
1054} *hammer_snapshot_data_t;
1055
1056/*
1057 * Config meta-data { ObjId = HAMMER_OBJID_ROOT, Key = 0, rectype = CONFIG }.
1058 *
1059 * Used to store the hammer cleanup config.  This data is not mirrored.
1060 */
1061typedef struct hammer_config_data {
1062    char        text[1024];
1063} *hammer_config_data_t;
1064
1065/*
1066 * Rollup various structures embedded as record data
1067 */
1068typedef union hammer_data_ondisk {
1069    struct hammer_direntry_data entry;
1070    struct hammer_inode_data inode;
1071    struct hammer_symlink_data symlink;
1072    struct hammer_pseudofs_data pfsd;
1073    struct hammer_snapshot_data snap;
1074    struct hammer_config_data config;
1075} *hammer_data_ondisk_t;
1076
1077/*
1078 * Ondisk layout of B-Tree related structures
1079 */
1080#include "hammer_btree.h"
1081
1082#define HAMMER_DIR_INODE_LOCALIZATION(ino_data)             \
1083    (((ino_data)->cap_flags & HAMMER_INODE_CAP_DIR_LOCAL_INO) ? \
1084     HAMMER_LOCALIZE_INODE :                    \
1085     HAMMER_LOCALIZE_MISC)
1086
1087#endif /* !VFS_HAMMER_DISK_H_ */
1088