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