1 /* 2 * Copyright (c) 2011-2012 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 #ifndef VFS_HAMMER2_DISK_H_ 36 #define VFS_HAMMER2_DISK_H_ 37 38 #ifndef _SYS_UUID_H_ 39 #include <sys/uuid.h> 40 #endif 41 #ifndef _SYS_DMSG_H_ 42 #include <sys/dmsg.h> 43 #endif 44 45 /* 46 * The structures below represent the on-disk media structures for the HAMMER2 47 * filesystem. Note that all fields for on-disk structures are naturally 48 * aligned. The host endian format is typically used - compatibility is 49 * possible if the implementation detects reversed endian and adjusts accesses 50 * accordingly. 51 * 52 * HAMMER2 primarily revolves around the directory topology: inodes, 53 * directory entries, and block tables. Block device buffer cache buffers 54 * are always 64KB. Logical file buffers are typically 16KB. All data 55 * references utilize 64-bit byte offsets. 56 * 57 * Free block management is handled independently using blocks reserved by 58 * the media topology. 59 */ 60 61 /* 62 * The data at the end of a file or directory may be a fragment in order 63 * to optimize storage efficiency. The minimum fragment size is 1KB. 64 * Since allocations are in powers of 2 fragments must also be sized in 65 * powers of 2 (1024, 2048, ... 65536). 66 * 67 * For the moment the maximum allocation size is HAMMER2_PBUFSIZE (64K), 68 * which is 2^16. Larger extents may be supported in the future. Smaller 69 * fragments might be supported in the future (down to 64 bytes is possible), 70 * but probably will not be. 71 * 72 * A full indirect block use supports 1024 x 64-byte blockrefs in a 64KB 73 * buffer. Indirect blocks down to 1KB are supported to keep small 74 * directories small. 75 * 76 * A maximally sized file (2^64-1 bytes) requires 5 indirect block levels. 77 * The hammer2_blockset in the volume header or file inode has another 8 78 * entries, giving us 66+3 = 69 bits of address space. However, some bits 79 * are taken up by (potentially) requests for redundant copies. HAMMER2 80 * currently supports up to 8 copies, which brings the address space down 81 * to 66 bits and gives us 2 bits of leeway. 82 */ 83 #define HAMMER2_MIN_ALLOC 1024 /* minimum allocation size */ 84 #define HAMMER2_MIN_RADIX 10 /* minimum allocation size 2^N */ 85 #define HAMMER2_MAX_ALLOC 65536 /* maximum allocation size */ 86 #define HAMMER2_MAX_RADIX 16 /* maximum allocation size 2^N */ 87 #define HAMMER2_KEY_RADIX 64 /* number of bits in key */ 88 89 /* 90 * MINALLOCSIZE - The minimum allocation size. This can be smaller 91 * or larger than the minimum physical IO size. 92 * 93 * NOTE: Should not be larger than 1K since inodes 94 * are 1K. 95 * 96 * MINIOSIZE - The minimum IO size. This must be less than 97 * or equal to HAMMER2_LBUFSIZE. 98 * 99 * HAMMER2_LBUFSIZE - Nominal buffer size for I/O rollups. 100 * 101 * HAMMER2_PBUFSIZE - Topological block size used by files for all 102 * blocks except the block straddling EOF. 103 * 104 * HAMMER2_SEGSIZE - Allocation map segment size, typically 2MB 105 * (space represented by a level0 bitmap). 106 */ 107 108 #define HAMMER2_SEGSIZE (1 << HAMMER2_FREEMAP_LEVEL0_RADIX) 109 #define HAMMER2_SEGRADIX HAMMER2_FREEMAP_LEVEL0_RADIX 110 111 #define HAMMER2_PBUFRADIX 16 /* physical buf (1<<16) bytes */ 112 #define HAMMER2_PBUFSIZE 65536 113 #define HAMMER2_LBUFRADIX 14 /* logical buf (1<<14) bytes */ 114 #define HAMMER2_LBUFSIZE 16384 115 116 /* 117 * Generally speaking we want to use 16K and 64K I/Os 118 */ 119 #define HAMMER2_MINIORADIX HAMMER2_LBUFRADIX 120 #define HAMMER2_MINIOSIZE HAMMER2_LBUFSIZE 121 122 #define HAMMER2_IND_BYTES_MIN HAMMER2_LBUFSIZE 123 #define HAMMER2_IND_BYTES_MAX HAMMER2_PBUFSIZE 124 #define HAMMER2_IND_COUNT_MIN (HAMMER2_IND_BYTES_MIN / \ 125 sizeof(hammer2_blockref_t)) 126 #define HAMMER2_IND_COUNT_MAX (HAMMER2_IND_BYTES_MAX / \ 127 sizeof(hammer2_blockref_t)) 128 129 /* 130 * In HAMMER2, arrays of blockrefs are fully set-associative, meaning that 131 * any element can occur at any index and holes can be anywhere. As a 132 * future optimization we will be able to flag that such arrays are sorted 133 * and thus optimize lookups, but for now we don't. 134 * 135 * Inodes embed either 512 bytes of direct data or an array of 8 blockrefs, 136 * resulting in highly efficient storage for files <= 512 bytes and for files 137 * <= 512KB. Up to 8 directory entries can be referenced from a directory 138 * without requiring an indirect block. 139 * 140 * Indirect blocks are typically either 4KB (64 blockrefs / ~4MB represented), 141 * or 64KB (1024 blockrefs / ~64MB represented). 142 */ 143 #define HAMMER2_SET_COUNT 8 /* direct entries */ 144 #define HAMMER2_SET_RADIX 3 145 #define HAMMER2_EMBEDDED_BYTES 512 /* inode blockset/dd size */ 146 #define HAMMER2_EMBEDDED_RADIX 9 147 148 #define HAMMER2_PBUFMASK (HAMMER2_PBUFSIZE - 1) 149 #define HAMMER2_LBUFMASK (HAMMER2_LBUFSIZE - 1) 150 #define HAMMER2_SEGMASK (HAMMER2_SEGSIZE - 1) 151 152 #define HAMMER2_LBUFMASK64 ((hammer2_off_t)HAMMER2_LBUFMASK) 153 #define HAMMER2_PBUFSIZE64 ((hammer2_off_t)HAMMER2_PBUFSIZE) 154 #define HAMMER2_PBUFMASK64 ((hammer2_off_t)HAMMER2_PBUFMASK) 155 #define HAMMER2_SEGSIZE64 ((hammer2_off_t)HAMMER2_SEGSIZE) 156 #define HAMMER2_SEGMASK64 ((hammer2_off_t)HAMMER2_SEGMASK) 157 158 #define HAMMER2_UUID_STRING "5cbb9ad1-862d-11dc-a94d-01301bb8a9f5" 159 160 /* 161 * A HAMMER2 filesystem is always sized in multiples of 8MB. 162 * 163 * A 4MB segment is reserved at the beginning of each 2GB zone. This segment 164 * contains the volume header (or backup volume header), the free block 165 * table, and possibly other information in the future. 166 * 167 * 4MB = 64 x 64K blocks. Each 4MB segment is broken down as follows: 168 * 169 * +-----------------------+ 170 * | Volume Hdr | block 0 volume header & alternates 171 * +-----------------------+ (first four zones only) 172 * | FreeBlk Section A | block 1-4 173 * +-----------------------+ 174 * | FreeBlk Section B | block 5-8 175 * +-----------------------+ 176 * | FreeBlk Section C | block 9-12 177 * +-----------------------+ 178 * | FreeBlk Section D | block 13-16 179 * +-----------------------+ 180 * | | block 17...63 181 * | reserved | 182 * | | 183 * +-----------------------+ 184 * 185 * The first few 2GB zones contain volume headers and volume header backups. 186 * After that the volume header block# is reserved. 187 * 188 * Freemap (see the FREEMAP document) 189 * 190 * The freemap utilizes blocks #1-16 for now, see the FREEMAP document. 191 * The filesystems rotations through the sections to avoid disturbing the 192 * 'previous' version of the freemap during a flush. 193 * 194 * Each freemap section is 4 x 64K blocks and represents 2GB, 2TB, 2PB, 195 * and 2EB indirect map, plus the volume header has a set of 8 blockrefs 196 * for another 3 bits for a total of 64 bits of address space. The Level 0 197 * 64KB block representing 2GB of storage is a hammer2_bmap_data[1024]. 198 * Each element contains a 128x2 bit bitmap representing 16KB per chunk for 199 * 2MB of storage (x1024 elements = 2GB). 2 bits per chunk: 200 * 201 * 00 Free 202 * 01 Possibly fragmented 203 * 10 Possibly free 204 * 11 Allocated 205 * 206 * One important thing to note here is that the freemap resolution is 16KB, 207 * but the minimuim storage allocation size is 1KB. The hammer2 vfs keeps 208 * track of sub-allocations in memory (on umount or reboot obvious the whole 209 * 16KB will be considered allocated even if only 1KB is allocated). It is 210 * possible for fragmentation to build up over time. 211 * 212 * The Second thing to note is that due to the way snapshots and inode 213 * replication works, deleting a file cannot immediately free the related 214 * space. Instead, the freemap elements transition from 11->10. The bulk 215 * freeing code which does a complete scan is then responsible for 216 * transitioning the elements to 00 or back to 11 or to 01 for that matter. 217 * 218 * WARNING! ZONE_SEG and VOLUME_ALIGN must be a multiple of 1<<LEVEL0_RADIX 219 * (i.e. a multiple of 2MB). VOLUME_ALIGN must be >= ZONE_SEG. 220 */ 221 #define HAMMER2_VOLUME_ALIGN (8 * 1024 * 1024) 222 #define HAMMER2_VOLUME_ALIGN64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGN) 223 #define HAMMER2_VOLUME_ALIGNMASK (HAMMER2_VOLUME_ALIGN - 1) 224 #define HAMMER2_VOLUME_ALIGNMASK64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGNMASK) 225 226 #define HAMMER2_NEWFS_ALIGN (HAMMER2_VOLUME_ALIGN) 227 #define HAMMER2_NEWFS_ALIGN64 ((hammer2_off_t)HAMMER2_VOLUME_ALIGN) 228 #define HAMMER2_NEWFS_ALIGNMASK (HAMMER2_VOLUME_ALIGN - 1) 229 #define HAMMER2_NEWFS_ALIGNMASK64 ((hammer2_off_t)HAMMER2_NEWFS_ALIGNMASK) 230 231 #define HAMMER2_ZONE_BYTES64 (2LLU * 1024 * 1024 * 1024) 232 #define HAMMER2_ZONE_MASK64 (HAMMER2_ZONE_BYTES64 - 1) 233 #define HAMMER2_ZONE_SEG (4 * 1024 * 1024) 234 #define HAMMER2_ZONE_SEG64 ((hammer2_off_t)HAMMER2_ZONE_SEG) 235 #define HAMMER2_ZONE_BLOCKS_SEG (HAMMER2_ZONE_SEG / HAMMER2_PBUFSIZE) 236 237 /* 238 * 64 x 64KB blocks are reserved at the base of each 2GB zone. These blocks 239 * are used to store the volume header or volume header backups, allocation 240 * tree, and other information in the future. 241 * 242 * All specified blocks are not necessarily used in all 2GB zones. However, 243 * dead areas are reserved for future use and MUST NOT BE USED for other 244 * purposes. 245 * 246 * The freemap is arranged into four groups. Modifications rotate through 247 * the groups on a block by block basis (so all the blocks are not necessarily 248 * synchronized to the same group). Because the freemap is flushed 249 * independent of the main filesystem, the freemap only really needs two 250 * groups to operate efficiently. 251 * 252 * 253 * 254 */ 255 #define HAMMER2_ZONE_VOLHDR 0 /* volume header or backup */ 256 #define HAMMER2_ZONE_FREEMAP_A 1 /* freemap layer group A */ 257 #define HAMMER2_ZONE_FREEMAP_B 5 /* freemap layer group B */ 258 #define HAMMER2_ZONE_FREEMAP_C 9 /* freemap layer group C */ 259 #define HAMMER2_ZONE_FREEMAP_D 13 /* freemap layer group D */ 260 261 /* relative to FREEMAP_x */ 262 #define HAMMER2_ZONEFM_LEVEL1 0 /* 2GB leafmap */ 263 #define HAMMER2_ZONEFM_LEVEL2 1 /* 2TB indmap */ 264 #define HAMMER2_ZONEFM_LEVEL3 2 /* 2PB indmap */ 265 #define HAMMER2_ZONEFM_LEVEL4 3 /* 2EB indmap */ 266 /* LEVEL5 is a set of 8 blockrefs in the volume header 16EB */ 267 268 269 /* 270 * Freemap radii. Please note that LEVEL 1 blockref array entries 271 * point to 256-byte sections of the bitmap representing 2MB of storage. 272 * Even though the chain structures represent only 256 bytes, they are 273 * mapped using larger 16K or 64K buffer cache buffers. 274 */ 275 #define HAMMER2_FREEMAP_LEVEL5_RADIX 64 /* 16EB */ 276 #define HAMMER2_FREEMAP_LEVEL4_RADIX 61 /* 2EB */ 277 #define HAMMER2_FREEMAP_LEVEL3_RADIX 51 /* 2PB */ 278 #define HAMMER2_FREEMAP_LEVEL2_RADIX 41 /* 2TB */ 279 #define HAMMER2_FREEMAP_LEVEL1_RADIX 31 /* 2GB */ 280 #define HAMMER2_FREEMAP_LEVEL0_RADIX 21 /* 2MB (entry in l-1 leaf) */ 281 282 #define HAMMER2_FREEMAP_LEVELN_PSIZE 65536 /* physical bytes */ 283 284 #define HAMMER2_FREEMAP_COUNT (int)(HAMMER2_FREEMAP_LEVELN_PSIZE / \ 285 sizeof(hammer2_bmap_data_t)) 286 #define HAMMER2_FREEMAP_BLOCK_RADIX 14 287 #define HAMMER2_FREEMAP_BLOCK_SIZE (1 << HAMMER2_FREEMAP_BLOCK_RADIX) 288 #define HAMMER2_FREEMAP_BLOCK_MASK (HAMMER2_FREEMAP_BLOCK_SIZE - 1) 289 290 /* 291 * Two linear areas can be reserved after the initial 2MB segment in the base 292 * zone (the one starting at offset 0). These areas are NOT managed by the 293 * block allocator and do not fall under HAMMER2 crc checking rules based 294 * at the volume header (but can be self-CRCd internally, depending). 295 */ 296 #define HAMMER2_BOOT_MIN_BYTES HAMMER2_VOLUME_ALIGN 297 #define HAMMER2_BOOT_NOM_BYTES (64*1024*1024) 298 #define HAMMER2_BOOT_MAX_BYTES (256*1024*1024) 299 300 #define HAMMER2_REDO_MIN_BYTES HAMMER2_VOLUME_ALIGN 301 #define HAMMER2_REDO_NOM_BYTES (256*1024*1024) 302 #define HAMMER2_REDO_MAX_BYTES (1024*1024*1024) 303 304 /* 305 * Most HAMMER2 types are implemented as unsigned 64-bit integers. 306 * Transaction ids are monotonic. 307 * 308 * We utilize 32-bit iSCSI CRCs. 309 */ 310 typedef uint64_t hammer2_tid_t; 311 typedef uint64_t hammer2_off_t; 312 typedef uint64_t hammer2_key_t; 313 typedef uint32_t hammer2_crc32_t; 314 315 /* 316 * Miscellanious ranges (all are unsigned). 317 */ 318 #define HAMMER2_MIN_TID 1ULL 319 #define HAMMER2_MAX_TID 0xFFFFFFFFFFFFFFFFULL 320 #define HAMMER2_MIN_KEY 0ULL 321 #define HAMMER2_MAX_KEY 0xFFFFFFFFFFFFFFFFULL 322 #define HAMMER2_MIN_OFFSET 0ULL 323 #define HAMMER2_MAX_OFFSET 0xFFFFFFFFFFFFFFFFULL 324 325 /* 326 * HAMMER2 data offset special cases and masking. 327 * 328 * All HAMMER2 data offsets have to be broken down into a 64K buffer base 329 * offset (HAMMER2_OFF_MASK_HI) and a 64K buffer index (HAMMER2_OFF_MASK_LO). 330 * 331 * Indexes into physical buffers are always 64-byte aligned. The low 6 bits 332 * of the data offset field specifies how large the data chunk being pointed 333 * to as a power of 2. The theoretical minimum radix is thus 6 (The space 334 * needed in the low bits of the data offset field). However, the practical 335 * minimum allocation chunk size is 1KB (a radix of 10), so HAMMER2 sets 336 * HAMMER2_MIN_RADIX to 10. The maximum radix is currently 16 (64KB), but 337 * we fully intend to support larger extents in the future. 338 */ 339 #define HAMMER2_OFF_BAD ((hammer2_off_t)-1) 340 #define HAMMER2_OFF_MASK 0xFFFFFFFFFFFFFFC0ULL 341 #define HAMMER2_OFF_MASK_LO (HAMMER2_OFF_MASK & HAMMER2_PBUFMASK64) 342 #define HAMMER2_OFF_MASK_HI (~HAMMER2_PBUFMASK64) 343 #define HAMMER2_OFF_MASK_RADIX 0x000000000000003FULL 344 #define HAMMER2_MAX_COPIES 6 345 346 /* 347 * HAMMER2 directory support and pre-defined keys 348 */ 349 #define HAMMER2_DIRHASH_VISIBLE 0x8000000000000000ULL 350 #define HAMMER2_DIRHASH_USERMSK 0x7FFFFFFFFFFFFFFFULL 351 #define HAMMER2_DIRHASH_LOMASK 0x0000000000007FFFULL 352 #define HAMMER2_DIRHASH_HIMASK 0xFFFFFFFFFFFF0000ULL 353 #define HAMMER2_DIRHASH_FORCED 0x0000000000008000ULL /* bit forced on */ 354 355 #define HAMMER2_SROOT_KEY 0x0000000000000000ULL /* volume to sroot */ 356 357 /* 358 * The media block reference structure. This forms the core of the HAMMER2 359 * media topology recursion. This 64-byte data structure is embedded in the 360 * volume header, in inodes (which are also directory entries), and in 361 * indirect blocks. 362 * 363 * A blockref references a single media item, which typically can be a 364 * directory entry (aka inode), indirect block, or data block. 365 * 366 * The primary feature a blockref represents is the ability to validate 367 * the entire tree underneath it via its check code. Any modification to 368 * anything propagates up the blockref tree all the way to the root, replacing 369 * the related blocks. Propagations can shortcut to the volume root to 370 * implement the 'fast syncing' feature but this only delays the eventual 371 * propagation. 372 * 373 * The check code can be a simple 32-bit iscsi code, a 64-bit crc, 374 * or as complex as a 192 bit cryptographic hash. 192 bits is the maximum 375 * supported check code size, which is not sufficient for unverified dedup 376 * UNLESS one doesn't mind once-in-a-blue-moon data corruption (such as when 377 * farming web data). HAMMER2 has an unverified dedup feature for just this 378 * purpose. 379 * 380 * -- 381 * 382 * NOTE: The range of keys represented by the blockref is (key) to 383 * ((key) + (1LL << keybits) - 1). HAMMER2 usually populates 384 * blocks bottom-up, inserting a new root when radix expansion 385 * is required. 386 */ 387 struct hammer2_blockref { /* MUST BE EXACTLY 64 BYTES */ 388 uint8_t type; /* type of underlying item */ 389 uint8_t methods; /* check method & compression method */ 390 uint8_t copyid; /* specify which copy this is */ 391 uint8_t keybits; /* #of keybits masked off 0=leaf */ 392 uint8_t vradix; /* virtual data/meta-data size */ 393 uint8_t flags; /* blockref flags */ 394 uint8_t reserved06; 395 uint8_t reserved07; 396 hammer2_key_t key; /* key specification */ 397 hammer2_tid_t mirror_tid; /* propagate for mirror scan */ 398 hammer2_tid_t modify_tid; /* modifications sans propagation */ 399 hammer2_off_t data_off; /* low 6 bits is phys size (radix)*/ 400 union { /* check info */ 401 char buf[24]; 402 struct { 403 uint32_t value; 404 uint32_t unused[5]; 405 } iscsi32; 406 struct { 407 uint64_t value; 408 uint64_t unused[2]; 409 } crc64; 410 struct { 411 char data[24]; 412 } sha192; 413 414 /* 415 * Freemap hints are embedded in addition to the icrc32. 416 * 417 * bigmask - Radixes available for allocation (0-31). 418 * Heuristical (may be permissive but not 419 * restrictive). Typically only radix values 420 * 10-16 are used (i.e. (1<<10) through (1<<16)). 421 * 422 * avail - Total available space remaining, in bytes 423 */ 424 struct { 425 uint32_t icrc32; 426 uint32_t bigmask; /* available radixes */ 427 uint64_t avail; /* total available bytes */ 428 uint64_t unused; /* unused must be 0 */ 429 } freemap; 430 } check; 431 }; 432 433 typedef struct hammer2_blockref hammer2_blockref_t; 434 435 #if 0 436 #define HAMMER2_BREF_SYNC1 0x01 /* modification synchronized */ 437 #define HAMMER2_BREF_SYNC2 0x02 /* modification committed */ 438 #define HAMMER2_BREF_DESYNCCHLD 0x04 /* desynchronize children */ 439 #define HAMMER2_BREF_DELETED 0x80 /* indicates a deletion */ 440 #endif 441 442 #define HAMMER2_BLOCKREF_BYTES 64 /* blockref struct in bytes */ 443 444 /* 445 * On-media and off-media blockref types. 446 */ 447 #define HAMMER2_BREF_TYPE_EMPTY 0 448 #define HAMMER2_BREF_TYPE_INODE 1 449 #define HAMMER2_BREF_TYPE_INDIRECT 2 450 #define HAMMER2_BREF_TYPE_DATA 3 451 #define HAMMER2_BREF_TYPE_UNUSED04 4 452 #define HAMMER2_BREF_TYPE_FREEMAP_NODE 5 453 #define HAMMER2_BREF_TYPE_FREEMAP_LEAF 6 454 #define HAMMER2_BREF_TYPE_FREEMAP 254 /* pseudo-type */ 455 #define HAMMER2_BREF_TYPE_VOLUME 255 /* pseudo-type */ 456 457 #define HAMMER2_ENC_CHECK(n) ((n) << 4) 458 #define HAMMER2_DEC_CHECK(n) (((n) >> 4) & 15) 459 460 #define HAMMER2_CHECK_NONE 0 461 #define HAMMER2_CHECK_ISCSI32 1 462 #define HAMMER2_CHECK_CRC64 2 463 #define HAMMER2_CHECK_SHA192 3 464 #define HAMMER2_CHECK_FREEMAP 4 465 466 #define HAMMER2_ENC_COMP(n) (n) 467 #define HAMMER2_ENC_LEVEL(n) ((n) << 4) 468 #define HAMMER2_DEC_COMP(n) ((n) & 15) 469 #define HAMMER2_DEC_LEVEL(n) (((n) >> 4) & 15) 470 471 #define HAMMER2_COMP_NONE 0 472 #define HAMMER2_COMP_AUTOZERO 1 473 #define HAMMER2_COMP_LZ4 2 474 #define HAMMER2_COMP_ZLIB 3 475 476 #define HAMMER2_COMP_NEWFS_DEFAULT HAMMER2_COMP_LZ4 477 #define HAMMER2_COMP_STRINGS { "none", "autozero", "lz4", "zlib" } 478 #define HAMMER2_COMP_STRINGS_COUNT 4 479 480 481 /* 482 * HAMMER2 block references are collected into sets of 8 blockrefs. These 483 * sets are fully associative, meaning the elements making up a set are 484 * not sorted in any way and may contain duplicate entries, holes, or 485 * entries which shortcut multiple levels of indirection. Sets are used 486 * in various ways: 487 * 488 * (1) When redundancy is desired a set may contain several duplicate 489 * entries pointing to different copies of the same data. Up to 8 copies 490 * are supported but the set structure becomes a bit inefficient once 491 * you go over 4. 492 * 493 * (2) The blockrefs in a set can shortcut multiple levels of indirections 494 * within the bounds imposed by the parent of set. 495 * 496 * When a set fills up another level of indirection is inserted, moving 497 * some or all of the set's contents into indirect blocks placed under the 498 * set. This is a top-down approach in that indirect blocks are not created 499 * until the set actually becomes full (that is, the entries in the set can 500 * shortcut the indirect blocks when the set is not full). Depending on how 501 * things are filled multiple indirect blocks will eventually be created. 502 * 503 * Indirect blocks are typically 4KB (64 entres) or 64KB (1024 entries) and 504 * are also treated as fully set-associative. 505 */ 506 struct hammer2_blockset { 507 hammer2_blockref_t blockref[HAMMER2_SET_COUNT]; 508 }; 509 510 typedef struct hammer2_blockset hammer2_blockset_t; 511 512 /* 513 * Catch programmer snafus 514 */ 515 #if (1 << HAMMER2_SET_RADIX) != HAMMER2_SET_COUNT 516 #error "hammer2 direct radix is incorrect" 517 #endif 518 #if (1 << HAMMER2_PBUFRADIX) != HAMMER2_PBUFSIZE 519 #error "HAMMER2_PBUFRADIX and HAMMER2_PBUFSIZE are inconsistent" 520 #endif 521 #if (1 << HAMMER2_MIN_RADIX) != HAMMER2_MIN_ALLOC 522 #error "HAMMER2_MIN_RADIX and HAMMER2_MIN_ALLOC are inconsistent" 523 #endif 524 525 /* 526 * hammer2_bmap_data - A freemap entry in the LEVEL1 block. 527 * 528 * Each 64-byte entry contains the bitmap and meta-data required to manage 529 * a LEVEL0 (2MB) block of storage. The storage is managed in 128 x 16KB 530 * chunks. Smaller allocation granularity is supported via a linear iterator 531 * and/or must otherwise be tracked in ram. 532 * 533 * (data structure must be 64 bytes exactly) 534 * 535 * linear - A BYTE linear allocation offset used for sub-16KB allocations 536 * only. May contain values between 0 and 2MB. Must be ignored 537 * if 16KB-aligned (i.e. force bitmap scan), otherwise may be 538 * used to sub-allocate within the 16KB block (which is already 539 * marked as allocated in the bitmap). 540 * 541 * Sub-allocations need only be 1KB-aligned and do not have to be 542 * size-aligned, and 16KB or larger allocations do not update this 543 * field, resulting in pretty good packing. 544 * 545 * Please note that file data granularity may be limited by 546 * other issues such as buffer cache direct-mapping and the 547 * desire to support sector sizes up to 16KB (so H2 only issues 548 * I/O's in multiples of 16KB anyway). 549 * 550 * class - Clustering class. Cleared to 0 only if the entire leaf becomes 551 * free. Used to cluster device buffers so all elements must have 552 * the same device block size, but may mix logical sizes. 553 * 554 * Typically integrated with the blockref type in the upper 8 bits 555 * to localize inodes and indrect blocks, improving bulk free scans 556 * and directory scans. 557 * 558 * bitmap - Two bits per 16KB allocation block arranged in arrays of 559 * 32-bit elements, 128x2 bits representing ~2MB worth of media 560 * storage. Bit patterns are as follows: 561 * 562 * 00 Unallocated 563 * 01 Armed for bulk free scan 564 * 10 Possibly free 565 * 11 Allocated 566 */ 567 struct hammer2_bmap_data { 568 int32_t linear; /* 00 linear sub-granular allocation offset */ 569 uint16_t class; /* 04-05 clustering class ((type<<8)|radix) */ 570 uint8_t reserved06; /* 06 */ 571 uint8_t reserved07; /* 07 */ 572 uint32_t reserved08; /* 08 */ 573 uint32_t reserved0C; /* 0C */ 574 uint32_t reserved10; /* 10 */ 575 uint32_t reserved14; /* 14 */ 576 uint32_t reserved18; /* 18 */ 577 uint32_t avail; /* 1C */ 578 uint32_t bitmap[8]; /* 20-3F 256 bits manages 2MB/16KB/2-bits */ 579 }; 580 581 typedef struct hammer2_bmap_data hammer2_bmap_data_t; 582 583 /* 584 * In HAMMER2 inodes ARE directory entries, with a special exception for 585 * hardlinks. The inode number is stored in the inode rather than being 586 * based on the location of the inode (since the location moves every time 587 * the inode or anything underneath the inode is modified). 588 * 589 * The inode is 1024 bytes, made up of 256 bytes of meta-data, 256 bytes 590 * for the filename, and 512 bytes worth of direct file data OR an embedded 591 * blockset. 592 * 593 * Directories represent one inode per blockref. Inodes are not laid out 594 * as a file but instead are represented by the related blockrefs. The 595 * blockrefs, in turn, are indexed by the 64-bit directory hash key. Remember 596 * that blocksets are fully associative, so a certain degree efficiency is 597 * achieved just from that. 598 * 599 * Up to 512 bytes of direct data can be embedded in an inode, and since 600 * inodes are essentially directory entries this also means that small data 601 * files end up simply being laid out linearly in the directory, resulting 602 * in fewer seeks and highly optimal access. 603 * 604 * The compression mode can be changed at any time in the inode and is 605 * recorded on a blockref-by-blockref basis. 606 * 607 * Hardlinks are supported via the inode map. Essentially the way a hardlink 608 * works is that all individual directory entries representing the same file 609 * are special cased and specify the same inode number. The actual file 610 * is placed in the nearest parent directory that is parent to all instances 611 * of the hardlink. If all hardlinks to a file are in the same directory 612 * the actual file will also be placed in that directory. This file uses 613 * the inode number as the directory entry key and is invisible to normal 614 * directory scans. Real directory entry keys are differentiated from the 615 * inode number key via bit 63. Access to the hardlink silently looks up 616 * the real file and forwards all operations to that file. Removal of the 617 * last hardlink also removes the real file. 618 * 619 * (attr_tid) is only updated when the inode's specific attributes or regular 620 * file size has changed, and affects path lookups and stat. (attr_tid) 621 * represents a special cache coherency lock under the inode. The inode 622 * blockref's modify_tid will always cover it. 623 * 624 * (dirent_tid) is only updated when an entry under a directory inode has 625 * been created, deleted, renamed, or had its attributes change, and affects 626 * directory lookups and scans. (dirent_tid) represents another special cache 627 * coherency lock under the inode. The inode blockref's modify_tid will 628 * always cover it. 629 */ 630 #define HAMMER2_INODE_BYTES 1024 /* (asserted by code) */ 631 #define HAMMER2_INODE_MAXNAME 256 /* maximum name in bytes */ 632 #define HAMMER2_INODE_VERSION_ONE 1 633 634 struct hammer2_inode_data { 635 uint16_t version; /* 0000 inode data version */ 636 uint16_t reserved02; /* 0002 */ 637 638 /* 639 * core inode attributes, inode type, misc flags 640 */ 641 uint32_t uflags; /* 0004 chflags */ 642 uint32_t rmajor; /* 0008 available for device nodes */ 643 uint32_t rminor; /* 000C available for device nodes */ 644 uint64_t ctime; /* 0010 inode change time */ 645 uint64_t mtime; /* 0018 modified time */ 646 uint64_t atime; /* 0020 access time (unsupported) */ 647 uint64_t btime; /* 0028 birth time */ 648 uuid_t uid; /* 0030 uid / degenerate unix uid */ 649 uuid_t gid; /* 0040 gid / degenerate unix gid */ 650 651 uint8_t type; /* 0050 object type */ 652 uint8_t op_flags; /* 0051 operational flags */ 653 uint16_t cap_flags; /* 0052 capability flags */ 654 uint32_t mode; /* 0054 unix modes (typ low 16 bits) */ 655 656 /* 657 * inode size, identification, localized recursive configuration 658 * for compression and backup copies. 659 */ 660 hammer2_tid_t inum; /* 0058 inode number */ 661 hammer2_off_t size; /* 0060 size of file */ 662 uint64_t nlinks; /* 0068 hard links (typ only dirs) */ 663 hammer2_tid_t iparent; /* 0070 parent inum (recovery only) */ 664 hammer2_key_t name_key; /* 0078 full filename key */ 665 uint16_t name_len; /* 0080 filename length */ 666 uint8_t ncopies; /* 0082 ncopies to local media */ 667 uint8_t comp_algo; /* 0083 compression request & algo */ 668 669 /* 670 * These fields are currently only applicable to PFSROOTs. 671 * 672 * NOTE: We can't use {volume_data->fsid, pfs_clid} to uniquely 673 * identify an instance of a PFS in the cluster because 674 * a mount may contain more than one copy of the PFS as 675 * a separate node. {pfs_clid, pfs_fsid} must be used for 676 * registration in the cluster. 677 */ 678 uint8_t target_type; /* 0084 hardlink target type */ 679 uint8_t reserved85; /* 0085 */ 680 uint8_t reserved86; /* 0086 */ 681 uint8_t pfs_type; /* 0087 (if PFSROOT) node type */ 682 uint64_t pfs_inum; /* 0088 (if PFSROOT) inum allocator */ 683 uuid_t pfs_clid; /* 0090 (if PFSROOT) cluster uuid */ 684 uuid_t pfs_fsid; /* 00A0 (if PFSROOT) unique uuid */ 685 686 /* 687 * Quotas and cumulative sub-tree counters. 688 */ 689 hammer2_key_t data_quota; /* 00B0 subtree quota in bytes */ 690 hammer2_key_t data_count; /* 00B8 subtree byte count */ 691 hammer2_key_t inode_quota; /* 00C0 subtree quota inode count */ 692 hammer2_key_t inode_count; /* 00C8 subtree inode count */ 693 hammer2_tid_t attr_tid; /* 00D0 attributes changed */ 694 hammer2_tid_t dirent_tid; /* 00D8 directory/attr changed */ 695 696 /* 697 * Tracks (possibly degenerate) free areas covering all sub-tree 698 * allocations under inode, not counting the inode itself. 699 * 0/0 indicates empty entry. fully set-associative. 700 */ 701 hammer2_off_t freezones[4]; /* 00E0/E8/F0/F8 base|radix */ 702 703 unsigned char filename[HAMMER2_INODE_MAXNAME]; 704 /* 0100-01FF (256 char, unterminated) */ 705 union { /* 0200-03FF (64x8 = 512 bytes) */ 706 struct hammer2_blockset blockset; 707 char data[HAMMER2_EMBEDDED_BYTES]; 708 } u; 709 }; 710 711 typedef struct hammer2_inode_data hammer2_inode_data_t; 712 713 #define HAMMER2_OPFLAG_DIRECTDATA 0x01 714 #define HAMMER2_OPFLAG_PFSROOT 0x02 715 #define HAMMER2_OPFLAG_COPYIDS 0x04 /* copyids override parent */ 716 717 #define HAMMER2_OBJTYPE_UNKNOWN 0 718 #define HAMMER2_OBJTYPE_DIRECTORY 1 719 #define HAMMER2_OBJTYPE_REGFILE 2 720 #define HAMMER2_OBJTYPE_FIFO 4 721 #define HAMMER2_OBJTYPE_CDEV 5 722 #define HAMMER2_OBJTYPE_BDEV 6 723 #define HAMMER2_OBJTYPE_SOFTLINK 7 724 #define HAMMER2_OBJTYPE_HARDLINK 8 /* dummy entry for hardlink */ 725 #define HAMMER2_OBJTYPE_SOCKET 9 726 #define HAMMER2_OBJTYPE_WHITEOUT 10 727 728 #define HAMMER2_COPYID_NONE 0 729 #define HAMMER2_COPYID_LOCAL ((uint8_t)-1) 730 731 /* 732 * PEER types identify connections and help cluster controller filter 733 * out unwanted SPANs. 734 */ 735 #define HAMMER2_PEER_NONE DMSG_PEER_NONE 736 #define HAMMER2_PEER_CLUSTER DMSG_PEER_CLUSTER 737 #define HAMMER2_PEER_BLOCK DMSG_PEER_BLOCK 738 #define HAMMER2_PEER_HAMMER2 DMSG_PEER_HAMMER2 739 740 #define HAMMER2_COPYID_COUNT DMSG_COPYID_COUNT 741 742 /* 743 * PFS types identify a PFS on media and in LNK_SPAN messages. 744 */ 745 #define HAMMER2_PFSTYPE_NONE DMSG_PFSTYPE_NONE 746 #define HAMMER2_PFSTYPE_ADMIN DMSG_PFSTYPE_ADMIN 747 #define HAMMER2_PFSTYPE_CLIENT DMSG_PFSTYPE_CLIENT 748 #define HAMMER2_PFSTYPE_CACHE DMSG_PFSTYPE_CACHE 749 #define HAMMER2_PFSTYPE_COPY DMSG_PFSTYPE_COPY 750 #define HAMMER2_PFSTYPE_SLAVE DMSG_PFSTYPE_SLAVE 751 #define HAMMER2_PFSTYPE_SOFT_SLAVE DMSG_PFSTYPE_SOFT_SLAVE 752 #define HAMMER2_PFSTYPE_SOFT_MASTER DMSG_PFSTYPE_SOFT_MASTER 753 #define HAMMER2_PFSTYPE_MASTER DMSG_PFSTYPE_MASTER 754 #define HAMMER2_PFSTYPE_SNAPSHOT DMSG_PFSTYPE_SNAPSHOT 755 #define HAMMER2_PFSTYPE_MAX DMSG_PFSTYPE_MAX 756 757 /* 758 * Allocation Table 759 * 760 */ 761 762 763 /* 764 * Flags (8 bits) - blockref, for freemap only 765 * 766 * Note that the minimum chunk size is 1KB so we could theoretically have 767 * 10 bits here, but we might have some future extension that allows a 768 * chunk size down to 256 bytes and if so we will need bits 8 and 9. 769 */ 770 #define HAMMER2_AVF_SELMASK 0x03 /* select group */ 771 #define HAMMER2_AVF_ALL_ALLOC 0x04 /* indicate all allocated */ 772 #define HAMMER2_AVF_ALL_FREE 0x08 /* indicate all free */ 773 #define HAMMER2_AVF_RESERVED10 0x10 774 #define HAMMER2_AVF_RESERVED20 0x20 775 #define HAMMER2_AVF_RESERVED40 0x40 776 #define HAMMER2_AVF_RESERVED80 0x80 777 #define HAMMER2_AVF_AVMASK32 ((uint32_t)0xFFFFFF00LU) 778 #define HAMMER2_AVF_AVMASK64 ((uint64_t)0xFFFFFFFFFFFFFF00LLU) 779 780 #define HAMMER2_AV_SELECT_A 0x00 781 #define HAMMER2_AV_SELECT_B 0x01 782 #define HAMMER2_AV_SELECT_C 0x02 783 #define HAMMER2_AV_SELECT_D 0x03 784 785 /* 786 * The volume header eats a 64K block. There is currently an issue where 787 * we want to try to fit all nominal filesystem updates in a 512-byte section 788 * but it may be a lost cause due to the need for a blockset. 789 * 790 * All information is stored in host byte order. The volume header's magic 791 * number may be checked to determine the byte order. If you wish to mount 792 * between machines w/ different endian modes you'll need filesystem code 793 * which acts on the media data consistently (either all one way or all the 794 * other). Our code currently does not do that. 795 * 796 * A read-write mount may have to recover missing allocations by doing an 797 * incremental mirror scan looking for modifications made after alloc_tid. 798 * If alloc_tid == last_tid then no recovery operation is needed. Recovery 799 * operations are usually very, very fast. 800 * 801 * Read-only mounts do not need to do any recovery, access to the filesystem 802 * topology is always consistent after a crash (is always consistent, period). 803 * However, there may be shortcutted blockref updates present from deep in 804 * the tree which are stored in the volumeh eader and must be tracked on 805 * the fly. 806 * 807 * NOTE: The copyinfo[] array contains the configuration for both the 808 * cluster connections and any local media copies. The volume 809 * header will be replicated for each local media copy. 810 * 811 * The mount command may specify multiple medias or just one and 812 * allow HAMMER2 to pick up the others when it checks the copyinfo[] 813 * array on mount. 814 * 815 * NOTE: root_blockref points to the super-root directory, not the root 816 * directory. The root directory will be a subdirectory under the 817 * super-root. 818 * 819 * The super-root directory contains all root directories and all 820 * snapshots (readonly or writable). It is possible to do a 821 * null-mount of the super-root using special path constructions 822 * relative to your mounted root. 823 * 824 * NOTE: HAMMER2 allows any subdirectory tree to be managed as if it were 825 * a PFS, including mirroring and storage quota operations, and this is 826 * prefered over creating discrete PFSs in the super-root. Instead 827 * the super-root is most typically used to create writable snapshots, 828 * alternative roots, and so forth. The super-root is also used by 829 * the automatic snapshotting mechanism. 830 */ 831 #define HAMMER2_VOLUME_ID_HBO 0x48414d3205172011LLU 832 #define HAMMER2_VOLUME_ID_ABO 0x11201705324d4148LLU 833 834 struct hammer2_volume_data { 835 /* 836 * sector #0 - 512 bytes 837 */ 838 uint64_t magic; /* 0000 Signature */ 839 hammer2_off_t boot_beg; /* 0008 Boot area (future) */ 840 hammer2_off_t boot_end; /* 0010 (size = end - beg) */ 841 hammer2_off_t aux_beg; /* 0018 Aux area (future) */ 842 hammer2_off_t aux_end; /* 0020 (size = end - beg) */ 843 hammer2_off_t volu_size; /* 0028 Volume size, bytes */ 844 845 uint32_t version; /* 0030 */ 846 uint32_t flags; /* 0034 */ 847 uint8_t copyid; /* 0038 copyid of phys vol */ 848 uint8_t freemap_version; /* 0039 freemap algorithm */ 849 uint8_t peer_type; /* 003A HAMMER2_PEER_xxx */ 850 uint8_t reserved003B; /* 003B */ 851 uint32_t reserved003C; /* 003C */ 852 853 uuid_t fsid; /* 0040 */ 854 uuid_t fstype; /* 0050 */ 855 856 /* 857 * allocator_size is precalculated at newfs time and does not include 858 * reserved blocks, boot, or redo areas. 859 * 860 * Initial non-reserved-area allocations do not use the freemap 861 * but instead adjust alloc_iterator. Dynamic allocations take 862 * over starting at (allocator_beg). This makes newfs_hammer2's 863 * job a lot easier and can also serve as a testing jig. 864 */ 865 hammer2_off_t allocator_size; /* 0060 Total data space */ 866 hammer2_off_t allocator_free; /* 0068 Free space */ 867 hammer2_off_t allocator_beg; /* 0070 Initial allocations */ 868 hammer2_tid_t mirror_tid; /* 0078 best committed tid */ 869 hammer2_tid_t alloc_tid; /* 0080 Alloctable modify tid */ 870 hammer2_blockref_t reserved0088; /* 0088-00C7 */ 871 872 /* 873 * Copyids are allocated dynamically from the copyexists bitmap. 874 * An id from the active copies set (up to 8, see copyinfo later on) 875 * may still exist after the copy set has been removed from the 876 * volume header and its bit will remain active in the bitmap and 877 * cannot be reused until it is 100% removed from the hierarchy. 878 */ 879 uint32_t copyexists[8]; /* 00C8-00E7 copy exists bmap */ 880 char reserved0140[248]; /* 00E8-01DF */ 881 882 /* 883 * 32 bit CRC array at the end of the first 512 byte sector. 884 * 885 * icrc_sects[7] - First 512-4 bytes of volume header (including all 886 * the other icrc's except this one). 887 * 888 * icrc_sects[6] - Sector 1 (512 bytes) of volume header, which is 889 * the blockset for the root. 890 * 891 * icrc_sects[5] - Sector 2 892 * icrc_sects[4] - Sector 3 893 * icrc_sects[3] - Sector 4 (the freemap blockset) 894 */ 895 hammer2_crc32_t icrc_sects[8]; /* 01E0-01FF */ 896 897 /* 898 * sector #1 - 512 bytes 899 * 900 * The entire sector is used by a blockset. 901 */ 902 hammer2_blockset_t sroot_blockset; /* 0200-03FF Superroot dir */ 903 904 /* 905 * sector #2-7 906 */ 907 char sector2[512]; /* 0400-05FF reserved */ 908 char sector3[512]; /* 0600-07FF reserved */ 909 hammer2_blockset_t freemap_blockset; /* 0800-09FF freemap */ 910 char sector5[512]; /* 0A00-0BFF reserved */ 911 char sector6[512]; /* 0C00-0DFF reserved */ 912 char sector7[512]; /* 0E00-0FFF reserved */ 913 914 /* 915 * sector #8-71 - 32768 bytes 916 * 917 * Contains the configuration for up to 256 copyinfo targets. These 918 * specify local and remote copies operating as masters or slaves. 919 * copyid's 0 and 255 are reserved (0 indicates an empty slot and 255 920 * indicates the local media). 921 * 922 * Each inode contains a set of up to 8 copyids, either inherited 923 * from its parent or explicitly specified in the inode, which 924 * indexes into this array. 925 */ 926 /* 1000-8FFF copyinfo config */ 927 dmsg_vol_data_t copyinfo[HAMMER2_COPYID_COUNT]; 928 929 /* 930 * Remaining sections are reserved for future use. 931 */ 932 char reserved0400[0x6FFC]; /* 9000-FFFB reserved */ 933 934 /* 935 * icrc on entire volume header 936 */ 937 hammer2_crc32_t icrc_volheader; /* FFFC-FFFF full volume icrc*/ 938 }; 939 940 typedef struct hammer2_volume_data hammer2_volume_data_t; 941 942 /* 943 * Various parts of the volume header have their own iCRCs. 944 * 945 * The first 512 bytes has its own iCRC stored at the end of the 512 bytes 946 * and not included the icrc calculation. 947 * 948 * The second 512 bytes also has its own iCRC but it is stored in the first 949 * 512 bytes so it covers the entire second 512 bytes. 950 * 951 * The whole volume block (64KB) has an iCRC covering all but the last 4 bytes, 952 * which is where the iCRC for the whole volume is stored. This is currently 953 * a catch-all for anything not individually iCRCd. 954 */ 955 #define HAMMER2_VOL_ICRC_SECT0 7 956 #define HAMMER2_VOL_ICRC_SECT1 6 957 958 #define HAMMER2_VOLUME_BYTES 65536 959 960 #define HAMMER2_VOLUME_ICRC0_OFF 0 961 #define HAMMER2_VOLUME_ICRC1_OFF 512 962 #define HAMMER2_VOLUME_ICRCVH_OFF 0 963 964 #define HAMMER2_VOLUME_ICRC0_SIZE (512 - 4) 965 #define HAMMER2_VOLUME_ICRC1_SIZE (512) 966 #define HAMMER2_VOLUME_ICRCVH_SIZE (65536 - 4) 967 968 #define HAMMER2_VOL_VERSION_MIN 1 969 #define HAMMER2_VOL_VERSION_DEFAULT 1 970 #define HAMMER2_VOL_VERSION_WIP 2 971 972 #define HAMMER2_NUM_VOLHDRS 4 973 974 union hammer2_media_data { 975 hammer2_volume_data_t voldata; 976 hammer2_inode_data_t ipdata; 977 hammer2_blockref_t npdata[HAMMER2_IND_COUNT_MAX]; 978 hammer2_bmap_data_t bmdata[HAMMER2_FREEMAP_COUNT]; 979 char buf[HAMMER2_PBUFSIZE]; 980 }; 981 982 typedef union hammer2_media_data hammer2_media_data_t; 983 984 #endif 985