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1#ifndef _BTRFS_CTREE_H_ 2#define _BTRFS_CTREE_H_ 3 4#include <linux/btrfs.h> 5#include <linux/types.h> 6 7/* 8 * This header contains the structure definitions and constants used 9 * by file system objects that can be retrieved using 10 * the BTRFS_IOC_SEARCH_TREE ioctl. That means basically anything that 11 * is needed to describe a leaf node's key or item contents. 12 */ 13 14/* holds pointers to all of the tree roots */ 15#define BTRFS_ROOT_TREE_OBJECTID 1ULL 16 17/* stores information about which extents are in use, and reference counts */ 18#define BTRFS_EXTENT_TREE_OBJECTID 2ULL 19 20/* 21 * chunk tree stores translations from logical -> physical block numbering 22 * the super block points to the chunk tree 23 */ 24#define BTRFS_CHUNK_TREE_OBJECTID 3ULL 25 26/* 27 * stores information about which areas of a given device are in use. 28 * one per device. The tree of tree roots points to the device tree 29 */ 30#define BTRFS_DEV_TREE_OBJECTID 4ULL 31 32/* one per subvolume, storing files and directories */ 33#define BTRFS_FS_TREE_OBJECTID 5ULL 34 35/* directory objectid inside the root tree */ 36#define BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL 37 38/* holds checksums of all the data extents */ 39#define BTRFS_CSUM_TREE_OBJECTID 7ULL 40 41/* holds quota configuration and tracking */ 42#define BTRFS_QUOTA_TREE_OBJECTID 8ULL 43 44/* for storing items that use the BTRFS_UUID_KEY* types */ 45#define BTRFS_UUID_TREE_OBJECTID 9ULL 46 47/* tracks free space in block groups. */ 48#define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL 49 50/* device stats in the device tree */ 51#define BTRFS_DEV_STATS_OBJECTID 0ULL 52 53/* for storing balance parameters in the root tree */ 54#define BTRFS_BALANCE_OBJECTID -4ULL 55 56/* orhpan objectid for tracking unlinked/truncated files */ 57#define BTRFS_ORPHAN_OBJECTID -5ULL 58 59/* does write ahead logging to speed up fsyncs */ 60#define BTRFS_TREE_LOG_OBJECTID -6ULL 61#define BTRFS_TREE_LOG_FIXUP_OBJECTID -7ULL 62 63/* for space balancing */ 64#define BTRFS_TREE_RELOC_OBJECTID -8ULL 65#define BTRFS_DATA_RELOC_TREE_OBJECTID -9ULL 66 67/* 68 * extent checksums all have this objectid 69 * this allows them to share the logging tree 70 * for fsyncs 71 */ 72#define BTRFS_EXTENT_CSUM_OBJECTID -10ULL 73 74/* For storing free space cache */ 75#define BTRFS_FREE_SPACE_OBJECTID -11ULL 76 77/* 78 * The inode number assigned to the special inode for storing 79 * free ino cache 80 */ 81#define BTRFS_FREE_INO_OBJECTID -12ULL 82 83/* dummy objectid represents multiple objectids */ 84#define BTRFS_MULTIPLE_OBJECTIDS -255ULL 85 86/* 87 * All files have objectids in this range. 88 */ 89#define BTRFS_FIRST_FREE_OBJECTID 256ULL 90#define BTRFS_LAST_FREE_OBJECTID -256ULL 91#define BTRFS_FIRST_CHUNK_TREE_OBJECTID 256ULL 92 93 94/* 95 * the device items go into the chunk tree. The key is in the form 96 * [ 1 BTRFS_DEV_ITEM_KEY device_id ] 97 */ 98#define BTRFS_DEV_ITEMS_OBJECTID 1ULL 99 100#define BTRFS_BTREE_INODE_OBJECTID 1 101 102#define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2 103 104#define BTRFS_DEV_REPLACE_DEVID 0ULL 105 106/* 107 * inode items have the data typically returned from stat and store other 108 * info about object characteristics. There is one for every file and dir in 109 * the FS 110 */ 111#define BTRFS_INODE_ITEM_KEY 1 112#define BTRFS_INODE_REF_KEY 12 113#define BTRFS_INODE_EXTREF_KEY 13 114#define BTRFS_XATTR_ITEM_KEY 24 115#define BTRFS_ORPHAN_ITEM_KEY 48 116/* reserve 2-15 close to the inode for later flexibility */ 117 118/* 119 * dir items are the name -> inode pointers in a directory. There is one 120 * for every name in a directory. 121 */ 122#define BTRFS_DIR_LOG_ITEM_KEY 60 123#define BTRFS_DIR_LOG_INDEX_KEY 72 124#define BTRFS_DIR_ITEM_KEY 84 125#define BTRFS_DIR_INDEX_KEY 96 126/* 127 * extent data is for file data 128 */ 129#define BTRFS_EXTENT_DATA_KEY 108 130 131/* 132 * extent csums are stored in a separate tree and hold csums for 133 * an entire extent on disk. 134 */ 135#define BTRFS_EXTENT_CSUM_KEY 128 136 137/* 138 * root items point to tree roots. They are typically in the root 139 * tree used by the super block to find all the other trees 140 */ 141#define BTRFS_ROOT_ITEM_KEY 132 142 143/* 144 * root backrefs tie subvols and snapshots to the directory entries that 145 * reference them 146 */ 147#define BTRFS_ROOT_BACKREF_KEY 144 148 149/* 150 * root refs make a fast index for listing all of the snapshots and 151 * subvolumes referenced by a given root. They point directly to the 152 * directory item in the root that references the subvol 153 */ 154#define BTRFS_ROOT_REF_KEY 156 155 156/* 157 * extent items are in the extent map tree. These record which blocks 158 * are used, and how many references there are to each block 159 */ 160#define BTRFS_EXTENT_ITEM_KEY 168 161 162/* 163 * The same as the BTRFS_EXTENT_ITEM_KEY, except it's metadata we already know 164 * the length, so we save the level in key->offset instead of the length. 165 */ 166#define BTRFS_METADATA_ITEM_KEY 169 167 168#define BTRFS_TREE_BLOCK_REF_KEY 176 169 170#define BTRFS_EXTENT_DATA_REF_KEY 178 171 172#define BTRFS_EXTENT_REF_V0_KEY 180 173 174#define BTRFS_SHARED_BLOCK_REF_KEY 182 175 176#define BTRFS_SHARED_DATA_REF_KEY 184 177 178/* 179 * block groups give us hints into the extent allocation trees. Which 180 * blocks are free etc etc 181 */ 182#define BTRFS_BLOCK_GROUP_ITEM_KEY 192 183 184/* 185 * Every block group is represented in the free space tree by a free space info 186 * item, which stores some accounting information. It is keyed on 187 * (block_group_start, FREE_SPACE_INFO, block_group_length). 188 */ 189#define BTRFS_FREE_SPACE_INFO_KEY 198 190 191/* 192 * A free space extent tracks an extent of space that is free in a block group. 193 * It is keyed on (start, FREE_SPACE_EXTENT, length). 194 */ 195#define BTRFS_FREE_SPACE_EXTENT_KEY 199 196 197/* 198 * When a block group becomes very fragmented, we convert it to use bitmaps 199 * instead of extents. A free space bitmap is keyed on 200 * (start, FREE_SPACE_BITMAP, length); the corresponding item is a bitmap with 201 * (length / sectorsize) bits. 202 */ 203#define BTRFS_FREE_SPACE_BITMAP_KEY 200 204 205#define BTRFS_DEV_EXTENT_KEY 204 206#define BTRFS_DEV_ITEM_KEY 216 207#define BTRFS_CHUNK_ITEM_KEY 228 208 209/* 210 * Records the overall state of the qgroups. 211 * There's only one instance of this key present, 212 * (0, BTRFS_QGROUP_STATUS_KEY, 0) 213 */ 214#define BTRFS_QGROUP_STATUS_KEY 240 215/* 216 * Records the currently used space of the qgroup. 217 * One key per qgroup, (0, BTRFS_QGROUP_INFO_KEY, qgroupid). 218 */ 219#define BTRFS_QGROUP_INFO_KEY 242 220/* 221 * Contains the user configured limits for the qgroup. 222 * One key per qgroup, (0, BTRFS_QGROUP_LIMIT_KEY, qgroupid). 223 */ 224#define BTRFS_QGROUP_LIMIT_KEY 244 225/* 226 * Records the child-parent relationship of qgroups. For 227 * each relation, 2 keys are present: 228 * (childid, BTRFS_QGROUP_RELATION_KEY, parentid) 229 * (parentid, BTRFS_QGROUP_RELATION_KEY, childid) 230 */ 231#define BTRFS_QGROUP_RELATION_KEY 246 232 233/* 234 * Obsolete name, see BTRFS_TEMPORARY_ITEM_KEY. 235 */ 236#define BTRFS_BALANCE_ITEM_KEY 248 237 238/* 239 * The key type for tree items that are stored persistently, but do not need to 240 * exist for extended period of time. The items can exist in any tree. 241 * 242 * [subtype, BTRFS_TEMPORARY_ITEM_KEY, data] 243 * 244 * Existing items: 245 * 246 * - balance status item 247 * (BTRFS_BALANCE_OBJECTID, BTRFS_TEMPORARY_ITEM_KEY, 0) 248 */ 249#define BTRFS_TEMPORARY_ITEM_KEY 248 250 251/* 252 * Obsolete name, see BTRFS_PERSISTENT_ITEM_KEY 253 */ 254#define BTRFS_DEV_STATS_KEY 249 255 256/* 257 * The key type for tree items that are stored persistently and usually exist 258 * for a long period, eg. filesystem lifetime. The item kinds can be status 259 * information, stats or preference values. The item can exist in any tree. 260 * 261 * [subtype, BTRFS_PERSISTENT_ITEM_KEY, data] 262 * 263 * Existing items: 264 * 265 * - device statistics, store IO stats in the device tree, one key for all 266 * stats 267 * (BTRFS_DEV_STATS_OBJECTID, BTRFS_DEV_STATS_KEY, 0) 268 */ 269#define BTRFS_PERSISTENT_ITEM_KEY 249 270 271/* 272 * Persistantly stores the device replace state in the device tree. 273 * The key is built like this: (0, BTRFS_DEV_REPLACE_KEY, 0). 274 */ 275#define BTRFS_DEV_REPLACE_KEY 250 276 277/* 278 * Stores items that allow to quickly map UUIDs to something else. 279 * These items are part of the filesystem UUID tree. 280 * The key is built like this: 281 * (UUID_upper_64_bits, BTRFS_UUID_KEY*, UUID_lower_64_bits). 282 */ 283#if BTRFS_UUID_SIZE != 16 284#error "UUID items require BTRFS_UUID_SIZE == 16!" 285#endif 286#define BTRFS_UUID_KEY_SUBVOL 251 /* for UUIDs assigned to subvols */ 287#define BTRFS_UUID_KEY_RECEIVED_SUBVOL 252 /* for UUIDs assigned to 288 * received subvols */ 289 290/* 291 * string items are for debugging. They just store a short string of 292 * data in the FS 293 */ 294#define BTRFS_STRING_ITEM_KEY 253 295 296 297 298/* 32 bytes in various csum fields */ 299#define BTRFS_CSUM_SIZE 32 300 301/* csum types */ 302#define BTRFS_CSUM_TYPE_CRC32 0 303 304/* 305 * flags definitions for directory entry item type 306 * 307 * Used by: 308 * struct btrfs_dir_item.type 309 */ 310#define BTRFS_FT_UNKNOWN 0 311#define BTRFS_FT_REG_FILE 1 312#define BTRFS_FT_DIR 2 313#define BTRFS_FT_CHRDEV 3 314#define BTRFS_FT_BLKDEV 4 315#define BTRFS_FT_FIFO 5 316#define BTRFS_FT_SOCK 6 317#define BTRFS_FT_SYMLINK 7 318#define BTRFS_FT_XATTR 8 319#define BTRFS_FT_MAX 9 320 321/* 322 * The key defines the order in the tree, and so it also defines (optimal) 323 * block layout. 324 * 325 * objectid corresponds to the inode number. 326 * 327 * type tells us things about the object, and is a kind of stream selector. 328 * so for a given inode, keys with type of 1 might refer to the inode data, 329 * type of 2 may point to file data in the btree and type == 3 may point to 330 * extents. 331 * 332 * offset is the starting byte offset for this key in the stream. 333 * 334 * btrfs_disk_key is in disk byte order. struct btrfs_key is always 335 * in cpu native order. Otherwise they are identical and their sizes 336 * should be the same (ie both packed) 337 */ 338struct btrfs_disk_key { 339 __le64 objectid; 340 __u8 type; 341 __le64 offset; 342} __attribute__ ((__packed__)); 343 344struct btrfs_key { 345 __u64 objectid; 346 __u8 type; 347 __u64 offset; 348} __attribute__ ((__packed__)); 349 350struct btrfs_dev_item { 351 /* the internal btrfs device id */ 352 __le64 devid; 353 354 /* size of the device */ 355 __le64 total_bytes; 356 357 /* bytes used */ 358 __le64 bytes_used; 359 360 /* optimal io alignment for this device */ 361 __le32 io_align; 362 363 /* optimal io width for this device */ 364 __le32 io_width; 365 366 /* minimal io size for this device */ 367 __le32 sector_size; 368 369 /* type and info about this device */ 370 __le64 type; 371 372 /* expected generation for this device */ 373 __le64 generation; 374 375 /* 376 * starting byte of this partition on the device, 377 * to allow for stripe alignment in the future 378 */ 379 __le64 start_offset; 380 381 /* grouping information for allocation decisions */ 382 __le32 dev_group; 383 384 /* seek speed 0-100 where 100 is fastest */ 385 __u8 seek_speed; 386 387 /* bandwidth 0-100 where 100 is fastest */ 388 __u8 bandwidth; 389 390 /* btrfs generated uuid for this device */ 391 __u8 uuid[BTRFS_UUID_SIZE]; 392 393 /* uuid of FS who owns this device */ 394 __u8 fsid[BTRFS_UUID_SIZE]; 395} __attribute__ ((__packed__)); 396 397struct btrfs_stripe { 398 __le64 devid; 399 __le64 offset; 400 __u8 dev_uuid[BTRFS_UUID_SIZE]; 401} __attribute__ ((__packed__)); 402 403struct btrfs_chunk { 404 /* size of this chunk in bytes */ 405 __le64 length; 406 407 /* objectid of the root referencing this chunk */ 408 __le64 owner; 409 410 __le64 stripe_len; 411 __le64 type; 412 413 /* optimal io alignment for this chunk */ 414 __le32 io_align; 415 416 /* optimal io width for this chunk */ 417 __le32 io_width; 418 419 /* minimal io size for this chunk */ 420 __le32 sector_size; 421 422 /* 2^16 stripes is quite a lot, a second limit is the size of a single 423 * item in the btree 424 */ 425 __le16 num_stripes; 426 427 /* sub stripes only matter for raid10 */ 428 __le16 sub_stripes; 429 struct btrfs_stripe stripe; 430 /* additional stripes go here */ 431} __attribute__ ((__packed__)); 432 433#define BTRFS_FREE_SPACE_EXTENT 1 434#define BTRFS_FREE_SPACE_BITMAP 2 435 436struct btrfs_free_space_entry { 437 __le64 offset; 438 __le64 bytes; 439 __u8 type; 440} __attribute__ ((__packed__)); 441 442struct btrfs_free_space_header { 443 struct btrfs_disk_key location; 444 __le64 generation; 445 __le64 num_entries; 446 __le64 num_bitmaps; 447} __attribute__ ((__packed__)); 448 449#define BTRFS_HEADER_FLAG_WRITTEN (1ULL << 0) 450#define BTRFS_HEADER_FLAG_RELOC (1ULL << 1) 451 452/* Super block flags */ 453/* Errors detected */ 454#define BTRFS_SUPER_FLAG_ERROR (1ULL << 2) 455 456#define BTRFS_SUPER_FLAG_SEEDING (1ULL << 32) 457#define BTRFS_SUPER_FLAG_METADUMP (1ULL << 33) 458 459 460/* 461 * items in the extent btree are used to record the objectid of the 462 * owner of the block and the number of references 463 */ 464 465struct btrfs_extent_item { 466 __le64 refs; 467 __le64 generation; 468 __le64 flags; 469} __attribute__ ((__packed__)); 470 471struct btrfs_extent_item_v0 { 472 __le32 refs; 473} __attribute__ ((__packed__)); 474 475 476#define BTRFS_EXTENT_FLAG_DATA (1ULL << 0) 477#define BTRFS_EXTENT_FLAG_TREE_BLOCK (1ULL << 1) 478 479/* following flags only apply to tree blocks */ 480 481/* use full backrefs for extent pointers in the block */ 482#define BTRFS_BLOCK_FLAG_FULL_BACKREF (1ULL << 8) 483 484/* 485 * this flag is only used internally by scrub and may be changed at any time 486 * it is only declared here to avoid collisions 487 */ 488#define BTRFS_EXTENT_FLAG_SUPER (1ULL << 48) 489 490struct btrfs_tree_block_info { 491 struct btrfs_disk_key key; 492 __u8 level; 493} __attribute__ ((__packed__)); 494 495struct btrfs_extent_data_ref { 496 __le64 root; 497 __le64 objectid; 498 __le64 offset; 499 __le32 count; 500} __attribute__ ((__packed__)); 501 502struct btrfs_shared_data_ref { 503 __le32 count; 504} __attribute__ ((__packed__)); 505 506struct btrfs_extent_inline_ref { 507 __u8 type; 508 __le64 offset; 509} __attribute__ ((__packed__)); 510 511/* old style backrefs item */ 512struct btrfs_extent_ref_v0 { 513 __le64 root; 514 __le64 generation; 515 __le64 objectid; 516 __le32 count; 517} __attribute__ ((__packed__)); 518 519 520/* dev extents record free space on individual devices. The owner 521 * field points back to the chunk allocation mapping tree that allocated 522 * the extent. The chunk tree uuid field is a way to double check the owner 523 */ 524struct btrfs_dev_extent { 525 __le64 chunk_tree; 526 __le64 chunk_objectid; 527 __le64 chunk_offset; 528 __le64 length; 529 __u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; 530} __attribute__ ((__packed__)); 531 532struct btrfs_inode_ref { 533 __le64 index; 534 __le16 name_len; 535 /* name goes here */ 536} __attribute__ ((__packed__)); 537 538struct btrfs_inode_extref { 539 __le64 parent_objectid; 540 __le64 index; 541 __le16 name_len; 542 __u8 name[0]; 543 /* name goes here */ 544} __attribute__ ((__packed__)); 545 546struct btrfs_timespec { 547 __le64 sec; 548 __le32 nsec; 549} __attribute__ ((__packed__)); 550 551struct btrfs_inode_item { 552 /* nfs style generation number */ 553 __le64 generation; 554 /* transid that last touched this inode */ 555 __le64 transid; 556 __le64 size; 557 __le64 nbytes; 558 __le64 block_group; 559 __le32 nlink; 560 __le32 uid; 561 __le32 gid; 562 __le32 mode; 563 __le64 rdev; 564 __le64 flags; 565 566 /* modification sequence number for NFS */ 567 __le64 sequence; 568 569 /* 570 * a little future expansion, for more than this we can 571 * just grow the inode item and version it 572 */ 573 __le64 reserved[4]; 574 struct btrfs_timespec atime; 575 struct btrfs_timespec ctime; 576 struct btrfs_timespec mtime; 577 struct btrfs_timespec otime; 578} __attribute__ ((__packed__)); 579 580struct btrfs_dir_log_item { 581 __le64 end; 582} __attribute__ ((__packed__)); 583 584struct btrfs_dir_item { 585 struct btrfs_disk_key location; 586 __le64 transid; 587 __le16 data_len; 588 __le16 name_len; 589 __u8 type; 590} __attribute__ ((__packed__)); 591 592#define BTRFS_ROOT_SUBVOL_RDONLY (1ULL << 0) 593 594/* 595 * Internal in-memory flag that a subvolume has been marked for deletion but 596 * still visible as a directory 597 */ 598#define BTRFS_ROOT_SUBVOL_DEAD (1ULL << 48) 599 600struct btrfs_root_item { 601 struct btrfs_inode_item inode; 602 __le64 generation; 603 __le64 root_dirid; 604 __le64 bytenr; 605 __le64 byte_limit; 606 __le64 bytes_used; 607 __le64 last_snapshot; 608 __le64 flags; 609 __le32 refs; 610 struct btrfs_disk_key drop_progress; 611 __u8 drop_level; 612 __u8 level; 613 614 /* 615 * The following fields appear after subvol_uuids+subvol_times 616 * were introduced. 617 */ 618 619 /* 620 * This generation number is used to test if the new fields are valid 621 * and up to date while reading the root item. Every time the root item 622 * is written out, the "generation" field is copied into this field. If 623 * anyone ever mounted the fs with an older kernel, we will have 624 * mismatching generation values here and thus must invalidate the 625 * new fields. See btrfs_update_root and btrfs_find_last_root for 626 * details. 627 * the offset of generation_v2 is also used as the start for the memset 628 * when invalidating the fields. 629 */ 630 __le64 generation_v2; 631 __u8 uuid[BTRFS_UUID_SIZE]; 632 __u8 parent_uuid[BTRFS_UUID_SIZE]; 633 __u8 received_uuid[BTRFS_UUID_SIZE]; 634 __le64 ctransid; /* updated when an inode changes */ 635 __le64 otransid; /* trans when created */ 636 __le64 stransid; /* trans when sent. non-zero for received subvol */ 637 __le64 rtransid; /* trans when received. non-zero for received subvol */ 638 struct btrfs_timespec ctime; 639 struct btrfs_timespec otime; 640 struct btrfs_timespec stime; 641 struct btrfs_timespec rtime; 642 __le64 reserved[8]; /* for future */ 643} __attribute__ ((__packed__)); 644 645/* 646 * this is used for both forward and backward root refs 647 */ 648struct btrfs_root_ref { 649 __le64 dirid; 650 __le64 sequence; 651 __le16 name_len; 652} __attribute__ ((__packed__)); 653 654struct btrfs_disk_balance_args { 655 /* 656 * profiles to operate on, single is denoted by 657 * BTRFS_AVAIL_ALLOC_BIT_SINGLE 658 */ 659 __le64 profiles; 660 661 /* 662 * usage filter 663 * BTRFS_BALANCE_ARGS_USAGE with a single value means '0..N' 664 * BTRFS_BALANCE_ARGS_USAGE_RANGE - range syntax, min..max 665 */ 666 union { 667 __le64 usage; 668 struct { 669 __le32 usage_min; 670 __le32 usage_max; 671 }; 672 }; 673 674 /* devid filter */ 675 __le64 devid; 676 677 /* devid subset filter [pstart..pend) */ 678 __le64 pstart; 679 __le64 pend; 680 681 /* btrfs virtual address space subset filter [vstart..vend) */ 682 __le64 vstart; 683 __le64 vend; 684 685 /* 686 * profile to convert to, single is denoted by 687 * BTRFS_AVAIL_ALLOC_BIT_SINGLE 688 */ 689 __le64 target; 690 691 /* BTRFS_BALANCE_ARGS_* */ 692 __le64 flags; 693 694 /* 695 * BTRFS_BALANCE_ARGS_LIMIT with value 'limit' 696 * BTRFS_BALANCE_ARGS_LIMIT_RANGE - the extend version can use minimum 697 * and maximum 698 */ 699 union { 700 __le64 limit; 701 struct { 702 __le32 limit_min; 703 __le32 limit_max; 704 }; 705 }; 706 707 /* 708 * Process chunks that cross stripes_min..stripes_max devices, 709 * BTRFS_BALANCE_ARGS_STRIPES_RANGE 710 */ 711 __le32 stripes_min; 712 __le32 stripes_max; 713 714 __le64 unused[6]; 715} __attribute__ ((__packed__)); 716 717/* 718 * store balance parameters to disk so that balance can be properly 719 * resumed after crash or unmount 720 */ 721struct btrfs_balance_item { 722 /* BTRFS_BALANCE_* */ 723 __le64 flags; 724 725 struct btrfs_disk_balance_args data; 726 struct btrfs_disk_balance_args meta; 727 struct btrfs_disk_balance_args sys; 728 729 __le64 unused[4]; 730} __attribute__ ((__packed__)); 731 732#define BTRFS_FILE_EXTENT_INLINE 0 733#define BTRFS_FILE_EXTENT_REG 1 734#define BTRFS_FILE_EXTENT_PREALLOC 2 735 736struct btrfs_file_extent_item { 737 /* 738 * transaction id that created this extent 739 */ 740 __le64 generation; 741 /* 742 * max number of bytes to hold this extent in ram 743 * when we split a compressed extent we can't know how big 744 * each of the resulting pieces will be. So, this is 745 * an upper limit on the size of the extent in ram instead of 746 * an exact limit. 747 */ 748 __le64 ram_bytes; 749 750 /* 751 * 32 bits for the various ways we might encode the data, 752 * including compression and encryption. If any of these 753 * are set to something a given disk format doesn't understand 754 * it is treated like an incompat flag for reading and writing, 755 * but not for stat. 756 */ 757 __u8 compression; 758 __u8 encryption; 759 __le16 other_encoding; /* spare for later use */ 760 761 /* are we inline data or a real extent? */ 762 __u8 type; 763 764 /* 765 * disk space consumed by the extent, checksum blocks are included 766 * in these numbers 767 * 768 * At this offset in the structure, the inline extent data start. 769 */ 770 __le64 disk_bytenr; 771 __le64 disk_num_bytes; 772 /* 773 * the logical offset in file blocks (no csums) 774 * this extent record is for. This allows a file extent to point 775 * into the middle of an existing extent on disk, sharing it 776 * between two snapshots (useful if some bytes in the middle of the 777 * extent have changed 778 */ 779 __le64 offset; 780 /* 781 * the logical number of file blocks (no csums included). This 782 * always reflects the size uncompressed and without encoding. 783 */ 784 __le64 num_bytes; 785 786} __attribute__ ((__packed__)); 787 788struct btrfs_csum_item { 789 __u8 csum; 790} __attribute__ ((__packed__)); 791 792struct btrfs_dev_stats_item { 793 /* 794 * grow this item struct at the end for future enhancements and keep 795 * the existing values unchanged 796 */ 797 __le64 values[BTRFS_DEV_STAT_VALUES_MAX]; 798} __attribute__ ((__packed__)); 799 800#define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS 0 801#define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID 1 802#define BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED 0 803#define BTRFS_DEV_REPLACE_ITEM_STATE_STARTED 1 804#define BTRFS_DEV_REPLACE_ITEM_STATE_SUSPENDED 2 805#define BTRFS_DEV_REPLACE_ITEM_STATE_FINISHED 3 806#define BTRFS_DEV_REPLACE_ITEM_STATE_CANCELED 4 807 808struct btrfs_dev_replace_item { 809 /* 810 * grow this item struct at the end for future enhancements and keep 811 * the existing values unchanged 812 */ 813 __le64 src_devid; 814 __le64 cursor_left; 815 __le64 cursor_right; 816 __le64 cont_reading_from_srcdev_mode; 817 818 __le64 replace_state; 819 __le64 time_started; 820 __le64 time_stopped; 821 __le64 num_write_errors; 822 __le64 num_uncorrectable_read_errors; 823} __attribute__ ((__packed__)); 824 825/* different types of block groups (and chunks) */ 826#define BTRFS_BLOCK_GROUP_DATA (1ULL << 0) 827#define BTRFS_BLOCK_GROUP_SYSTEM (1ULL << 1) 828#define BTRFS_BLOCK_GROUP_METADATA (1ULL << 2) 829#define BTRFS_BLOCK_GROUP_RAID0 (1ULL << 3) 830#define BTRFS_BLOCK_GROUP_RAID1 (1ULL << 4) 831#define BTRFS_BLOCK_GROUP_DUP (1ULL << 5) 832#define BTRFS_BLOCK_GROUP_RAID10 (1ULL << 6) 833#define BTRFS_BLOCK_GROUP_RAID5 (1ULL << 7) 834#define BTRFS_BLOCK_GROUP_RAID6 (1ULL << 8) 835#define BTRFS_BLOCK_GROUP_RESERVED (BTRFS_AVAIL_ALLOC_BIT_SINGLE | \ 836 BTRFS_SPACE_INFO_GLOBAL_RSV) 837 838enum btrfs_raid_types { 839 BTRFS_RAID_RAID10, 840 BTRFS_RAID_RAID1, 841 BTRFS_RAID_DUP, 842 BTRFS_RAID_RAID0, 843 BTRFS_RAID_SINGLE, 844 BTRFS_RAID_RAID5, 845 BTRFS_RAID_RAID6, 846 BTRFS_NR_RAID_TYPES 847}; 848 849#define BTRFS_BLOCK_GROUP_TYPE_MASK (BTRFS_BLOCK_GROUP_DATA | \ 850 BTRFS_BLOCK_GROUP_SYSTEM | \ 851 BTRFS_BLOCK_GROUP_METADATA) 852 853#define BTRFS_BLOCK_GROUP_PROFILE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \ 854 BTRFS_BLOCK_GROUP_RAID1 | \ 855 BTRFS_BLOCK_GROUP_RAID5 | \ 856 BTRFS_BLOCK_GROUP_RAID6 | \ 857 BTRFS_BLOCK_GROUP_DUP | \ 858 BTRFS_BLOCK_GROUP_RAID10) 859#define BTRFS_BLOCK_GROUP_RAID56_MASK (BTRFS_BLOCK_GROUP_RAID5 | \ 860 BTRFS_BLOCK_GROUP_RAID6) 861 862/* 863 * We need a bit for restriper to be able to tell when chunks of type 864 * SINGLE are available. This "extended" profile format is used in 865 * fs_info->avail_*_alloc_bits (in-memory) and balance item fields 866 * (on-disk). The corresponding on-disk bit in chunk.type is reserved 867 * to avoid remappings between two formats in future. 868 */ 869#define BTRFS_AVAIL_ALLOC_BIT_SINGLE (1ULL << 48) 870 871/* 872 * A fake block group type that is used to communicate global block reserve 873 * size to userspace via the SPACE_INFO ioctl. 874 */ 875#define BTRFS_SPACE_INFO_GLOBAL_RSV (1ULL << 49) 876 877#define BTRFS_EXTENDED_PROFILE_MASK (BTRFS_BLOCK_GROUP_PROFILE_MASK | \ 878 BTRFS_AVAIL_ALLOC_BIT_SINGLE) 879 880static inline __u64 chunk_to_extended(__u64 flags) 881{ 882 if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0) 883 flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE; 884 885 return flags; 886} 887static inline __u64 extended_to_chunk(__u64 flags) 888{ 889 return flags & ~BTRFS_AVAIL_ALLOC_BIT_SINGLE; 890} 891 892struct btrfs_block_group_item { 893 __le64 used; 894 __le64 chunk_objectid; 895 __le64 flags; 896} __attribute__ ((__packed__)); 897 898struct btrfs_free_space_info { 899 __le32 extent_count; 900 __le32 flags; 901} __attribute__ ((__packed__)); 902 903#define BTRFS_FREE_SPACE_USING_BITMAPS (1ULL << 0) 904 905#define BTRFS_QGROUP_LEVEL_SHIFT 48 906static inline __u64 btrfs_qgroup_level(__u64 qgroupid) 907{ 908 return qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT; 909} 910 911/* 912 * is subvolume quota turned on? 913 */ 914#define BTRFS_QGROUP_STATUS_FLAG_ON (1ULL << 0) 915/* 916 * RESCAN is set during the initialization phase 917 */ 918#define BTRFS_QGROUP_STATUS_FLAG_RESCAN (1ULL << 1) 919/* 920 * Some qgroup entries are known to be out of date, 921 * either because the configuration has changed in a way that 922 * makes a rescan necessary, or because the fs has been mounted 923 * with a non-qgroup-aware version. 924 * Turning qouta off and on again makes it inconsistent, too. 925 */ 926#define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT (1ULL << 2) 927 928#define BTRFS_QGROUP_STATUS_VERSION 1 929 930struct btrfs_qgroup_status_item { 931 __le64 version; 932 /* 933 * the generation is updated during every commit. As older 934 * versions of btrfs are not aware of qgroups, it will be 935 * possible to detect inconsistencies by checking the 936 * generation on mount time 937 */ 938 __le64 generation; 939 940 /* flag definitions see above */ 941 __le64 flags; 942 943 /* 944 * only used during scanning to record the progress 945 * of the scan. It contains a logical address 946 */ 947 __le64 rescan; 948} __attribute__ ((__packed__)); 949 950struct btrfs_qgroup_info_item { 951 __le64 generation; 952 __le64 rfer; 953 __le64 rfer_cmpr; 954 __le64 excl; 955 __le64 excl_cmpr; 956} __attribute__ ((__packed__)); 957 958struct btrfs_qgroup_limit_item { 959 /* 960 * only updated when any of the other values change 961 */ 962 __le64 flags; 963 __le64 max_rfer; 964 __le64 max_excl; 965 __le64 rsv_rfer; 966 __le64 rsv_excl; 967} __attribute__ ((__packed__)); 968 969#endif /* _BTRFS_CTREE_H_ */