/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * Copied from kernel/include/uapi/linux/btrfs_btree.h. * * Only modified the header. */ /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef __BTRFS_TREE_H__ #define __BTRFS_TREE_H__ #include #define BTRFS_MAGIC 0x4D5F53665248425FULL /* ascii _BHRfS_M, no null */ /* * The max metadata block size (node size). * * This limit is somewhat artificial. The memmove and tree block locking cost * go up with larger node size. */ #define BTRFS_MAX_METADATA_BLOCKSIZE 65536 /* * We can actually store much bigger names, but lets not confuse the rest * of linux. * * btrfs_dir_item::name_len follows this limitation. */ #define BTRFS_NAME_LEN 255 /* * Objectids start from here. * * Check btrfs_disk_key for the meaning of objectids. */ /* * Root tree holds pointers to all of the tree roots. * Without special mention, the root tree contains the root bytenr of all other * trees, except the chunk tree and the log tree. * * The super block contains the root bytenr of this tree. */ #define BTRFS_ROOT_TREE_OBJECTID 1ULL /* * Extent tree stores information about which extents are in use, and backrefs * for each extent. */ #define BTRFS_EXTENT_TREE_OBJECTID 2ULL /* * Chunk tree stores btrfs logical address -> physical address mapping. * * The super block contains part of chunk tree for bootstrap, and contains * the root bytenr of this tree. */ #define BTRFS_CHUNK_TREE_OBJECTID 3ULL /* * Device tree stores info about which areas of a given device are in use, * and physical address -> btrfs logical address mapping. */ #define BTRFS_DEV_TREE_OBJECTID 4ULL /* The fs tree is the first subvolume tree, storing files and directories. */ #define BTRFS_FS_TREE_OBJECTID 5ULL /* Shows the directory objectid inside the root tree. */ #define BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL /* Csum tree holds checksums of all the data extents. */ #define BTRFS_CSUM_TREE_OBJECTID 7ULL /* Quota tree holds quota configuration and tracking. */ #define BTRFS_QUOTA_TREE_OBJECTID 8ULL /* UUID tree stores items that use the BTRFS_UUID_KEY* types. */ #define BTRFS_UUID_TREE_OBJECTID 9ULL /* Free space cache tree (v2 space cache) tracks free space in block groups. */ #define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL /* Indicates device stats in the device tree. */ #define BTRFS_DEV_STATS_OBJECTID 0ULL /* For storing balance parameters in the root tree. */ #define BTRFS_BALANCE_OBJECTID -4ULL /* Orhpan objectid for tracking unlinked/truncated files. */ #define BTRFS_ORPHAN_OBJECTID -5ULL /* Does write ahead logging to speed up fsyncs. */ #define BTRFS_TREE_LOG_OBJECTID -6ULL #define BTRFS_TREE_LOG_FIXUP_OBJECTID -7ULL /* For space balancing. */ #define BTRFS_TREE_RELOC_OBJECTID -8ULL #define BTRFS_DATA_RELOC_TREE_OBJECTID -9ULL /* Extent checksums, shared between the csum tree and log trees. */ #define BTRFS_EXTENT_CSUM_OBJECTID -10ULL /* For storing free space cache (v1 space cache). */ #define BTRFS_FREE_SPACE_OBJECTID -11ULL /* The inode number assigned to the special inode for storing free ino cache. */ #define BTRFS_FREE_INO_OBJECTID -12ULL /* Dummy objectid represents multiple objectids. */ #define BTRFS_MULTIPLE_OBJECTIDS -255ULL /* All files have objectids in this range. */ #define BTRFS_FIRST_FREE_OBJECTID 256ULL #define BTRFS_LAST_FREE_OBJECTID -256ULL #define BTRFS_FIRST_CHUNK_TREE_OBJECTID 256ULL /* * The device items go into the chunk tree. * * The key is in the form * (BTRFS_DEV_ITEMS_OBJECTID, BTRFS_DEV_ITEM_KEY, ) */ #define BTRFS_DEV_ITEMS_OBJECTID 1ULL #define BTRFS_BTREE_INODE_OBJECTID 1 #define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2 #define BTRFS_DEV_REPLACE_DEVID 0ULL /* * Types start from here. * * Check btrfs_disk_key for details about types. */ /* * Inode items have the data typically returned from stat and store other * info about object characteristics. * * There is one for every file and dir in the FS. */ #define BTRFS_INODE_ITEM_KEY 1 /* reserve 2-11 close to the inode for later flexibility */ #define BTRFS_INODE_REF_KEY 12 #define BTRFS_INODE_EXTREF_KEY 13 #define BTRFS_XATTR_ITEM_KEY 24 #define BTRFS_ORPHAN_ITEM_KEY 48 /* * Dir items are the name -> inode pointers in a directory. * * There is one for every name in a directory. */ #define BTRFS_DIR_LOG_ITEM_KEY 60 #define BTRFS_DIR_LOG_INDEX_KEY 72 #define BTRFS_DIR_ITEM_KEY 84 #define BTRFS_DIR_INDEX_KEY 96 /* Stores info (position, size ...) about a data extent of a file */ #define BTRFS_EXTENT_DATA_KEY 108 /* * Extent csums are stored in a separate tree and hold csums for * an entire extent on disk. */ #define BTRFS_EXTENT_CSUM_KEY 128 /* * Root items point to tree roots. * * They are typically in the root tree used by the super block to find all the * other trees. */ #define BTRFS_ROOT_ITEM_KEY 132 /* * Root backrefs tie subvols and snapshots to the directory entries that * reference them. */ #define BTRFS_ROOT_BACKREF_KEY 144 /* * Root refs make a fast index for listing all of the snapshots and * subvolumes referenced by a given root. They point directly to the * directory item in the root that references the subvol. */ #define BTRFS_ROOT_REF_KEY 156 /* * Extent items are in the extent tree. * * These record which blocks are used, and how many references there are. */ #define BTRFS_EXTENT_ITEM_KEY 168 /* * The same as the BTRFS_EXTENT_ITEM_KEY, except it's metadata we already know * the length, so we save the level in key->offset instead of the length. */ #define BTRFS_METADATA_ITEM_KEY 169 #define BTRFS_TREE_BLOCK_REF_KEY 176 #define BTRFS_EXTENT_DATA_REF_KEY 178 #define BTRFS_EXTENT_REF_V0_KEY 180 #define BTRFS_SHARED_BLOCK_REF_KEY 182 #define BTRFS_SHARED_DATA_REF_KEY 184 /* * Block groups give us hints into the extent allocation trees. * * Stores how many free space there is in a block group. */ #define BTRFS_BLOCK_GROUP_ITEM_KEY 192 /* * Every block group is represented in the free space tree by a free space info * item, which stores some accounting information. It is keyed on * (block_group_start, FREE_SPACE_INFO, block_group_length). */ #define BTRFS_FREE_SPACE_INFO_KEY 198 /* * A free space extent tracks an extent of space that is free in a block group. * It is keyed on (start, FREE_SPACE_EXTENT, length). */ #define BTRFS_FREE_SPACE_EXTENT_KEY 199 /* * When a block group becomes very fragmented, we convert it to use bitmaps * instead of extents. * * A free space bitmap is keyed on (start, FREE_SPACE_BITMAP, length). * The corresponding item is a bitmap with (length / sectorsize) bits. */ #define BTRFS_FREE_SPACE_BITMAP_KEY 200 #define BTRFS_DEV_EXTENT_KEY 204 #define BTRFS_DEV_ITEM_KEY 216 #define BTRFS_CHUNK_ITEM_KEY 228 /* * Records the overall state of the qgroups. * * There's only one instance of this key present, * (0, BTRFS_QGROUP_STATUS_KEY, 0) */ #define BTRFS_QGROUP_STATUS_KEY 240 /* * Records the currently used space of the qgroup. * * One key per qgroup, (0, BTRFS_QGROUP_INFO_KEY, qgroupid). */ #define BTRFS_QGROUP_INFO_KEY 242 /* * Contains the user configured limits for the qgroup. * * One key per qgroup, (0, BTRFS_QGROUP_LIMIT_KEY, qgroupid). */ #define BTRFS_QGROUP_LIMIT_KEY 244 /* * Records the child-parent relationship of qgroups. For * each relation, 2 keys are present: * (childid, BTRFS_QGROUP_RELATION_KEY, parentid) * (parentid, BTRFS_QGROUP_RELATION_KEY, childid) */ #define BTRFS_QGROUP_RELATION_KEY 246 /* Obsolete name, see BTRFS_TEMPORARY_ITEM_KEY. */ #define BTRFS_BALANCE_ITEM_KEY 248 /* * The key type for tree items that are stored persistently, but do not need to * exist for extended period of time. The items can exist in any tree. * * [subtype, BTRFS_TEMPORARY_ITEM_KEY, data] * * Existing items: * * - balance status item * (BTRFS_BALANCE_OBJECTID, BTRFS_TEMPORARY_ITEM_KEY, 0) */ #define BTRFS_TEMPORARY_ITEM_KEY 248 /* Obsolete name, see BTRFS_PERSISTENT_ITEM_KEY */ #define BTRFS_DEV_STATS_KEY 249 /* * The key type for tree items that are stored persistently and usually exist * for a long period, eg. filesystem lifetime. The item kinds can be status * information, stats or preference values. The item can exist in any tree. * * [subtype, BTRFS_PERSISTENT_ITEM_KEY, data] * * Existing items: * * - device statistics, store IO stats in the device tree, one key for all * stats * (BTRFS_DEV_STATS_OBJECTID, BTRFS_DEV_STATS_KEY, 0) */ #define BTRFS_PERSISTENT_ITEM_KEY 249 /* * Persistently stores the device replace state in the device tree. * * The key is built like this: (0, BTRFS_DEV_REPLACE_KEY, 0). */ #define BTRFS_DEV_REPLACE_KEY 250 /* * Stores items that allow to quickly map UUIDs to something else. * * These items are part of the filesystem UUID tree. * The key is built like this: * (UUID_upper_64_bits, BTRFS_UUID_KEY*, UUID_lower_64_bits). */ #define BTRFS_UUID_KEY_SUBVOL 251 /* for UUIDs assigned to subvols */ #define BTRFS_UUID_KEY_RECEIVED_SUBVOL 252 /* for UUIDs assigned to * received subvols */ /* * String items are for debugging. * * They just store a short string of data in the FS. */ #define BTRFS_STRING_ITEM_KEY 253 /* 32 bytes in various csum fields */ #define BTRFS_CSUM_SIZE 32 /* Csum types */ enum btrfs_csum_type { BTRFS_CSUM_TYPE_CRC32 = 0, BTRFS_CSUM_TYPE_XXHASH = 1, BTRFS_CSUM_TYPE_SHA256 = 2, BTRFS_CSUM_TYPE_BLAKE2 = 3, }; /* * Flags definitions for directory entry item type. * * Used by: * struct btrfs_dir_item.type * * Values 0..7 must match common file type values in fs_types.h. */ #define BTRFS_FT_UNKNOWN 0 #define BTRFS_FT_REG_FILE 1 #define BTRFS_FT_DIR 2 #define BTRFS_FT_CHRDEV 3 #define BTRFS_FT_BLKDEV 4 #define BTRFS_FT_FIFO 5 #define BTRFS_FT_SOCK 6 #define BTRFS_FT_SYMLINK 7 #define BTRFS_FT_XATTR 8 #define BTRFS_FT_MAX 9 #define BTRFS_FSID_SIZE 16 #define BTRFS_UUID_SIZE 16 /* * The key defines the order in the tree, and so it also defines (optimal) * block layout. * * Objectid and offset are interpreted based on type. * While normally for objectid, it either represents a root number, or an * inode number. * * Type tells us things about the object, and is a kind of stream selector. * Check the following URL for full references about btrfs_disk_key/btrfs_key: * https://btrfs.wiki.kernel.org/index.php/Btree_Items * * btrfs_disk_key is in disk byte order. struct btrfs_key is always * in cpu native order. Otherwise they are identical and their sizes * should be the same (ie both packed) */ struct btrfs_disk_key { __le64 objectid; __u8 type; __le64 offset; } __attribute__ ((__packed__)); struct btrfs_key { __u64 objectid; __u8 type; __u64 offset; } __attribute__ ((__packed__)); struct btrfs_dev_item { /* The internal btrfs device id */ __le64 devid; /* Size of the device */ __le64 total_bytes; /* Bytes used */ __le64 bytes_used; /* Optimal io alignment for this device */ __le32 io_align; /* Optimal io width for this device */ __le32 io_width; /* Minimal io size for this device */ __le32 sector_size; /* Type and info about this device */ __le64 type; /* Expected generation for this device */ __le64 generation; /* * Starting byte of this partition on the device, * to allow for stripe alignment in the future. */ __le64 start_offset; /* Grouping information for allocation decisions */ __le32 dev_group; /* Optimal seek speed 0-100 where 100 is fastest */ __u8 seek_speed; /* Optimal bandwidth 0-100 where 100 is fastest */ __u8 bandwidth; /* Btrfs generated uuid for this device */ __u8 uuid[BTRFS_UUID_SIZE]; /* UUID of FS who owns this device */ __u8 fsid[BTRFS_UUID_SIZE]; } __attribute__ ((__packed__)); struct btrfs_stripe { __le64 devid; __le64 offset; __u8 dev_uuid[BTRFS_UUID_SIZE]; } __attribute__ ((__packed__)); struct btrfs_chunk { /* Size of this chunk in bytes */ __le64 length; /* Objectid of the root referencing this chunk */ __le64 owner; __le64 stripe_len; __le64 type; /* Optimal io alignment for this chunk */ __le32 io_align; /* Optimal io width for this chunk */ __le32 io_width; /* Minimal io size for this chunk */ __le32 sector_size; /* * 2^16 stripes is quite a lot, a second limit is the size of a single * item in the btree. */ __le16 num_stripes; /* Sub stripes only matter for raid10 */ __le16 sub_stripes; struct btrfs_stripe stripe; /* additional stripes go here */ } __attribute__ ((__packed__)); #define BTRFS_FREE_SPACE_EXTENT 1 #define BTRFS_FREE_SPACE_BITMAP 2 struct btrfs_free_space_entry { __le64 offset; __le64 bytes; __u8 type; } __attribute__ ((__packed__)); struct btrfs_free_space_header { struct btrfs_disk_key location; __le64 generation; __le64 num_entries; __le64 num_bitmaps; } __attribute__ ((__packed__)); #define BTRFS_HEADER_FLAG_WRITTEN (1ULL << 0) #define BTRFS_HEADER_FLAG_RELOC (1ULL << 1) /* Super block flags */ /* Errors detected */ #define BTRFS_SUPER_FLAG_ERROR (1ULL << 2) #define BTRFS_SUPER_FLAG_SEEDING (1ULL << 32) #define BTRFS_SUPER_FLAG_METADUMP (1ULL << 33) #define BTRFS_SUPER_FLAG_METADUMP_V2 (1ULL << 34) #define BTRFS_SUPER_FLAG_CHANGING_FSID (1ULL << 35) #define BTRFS_SUPER_FLAG_CHANGING_FSID_V2 (1ULL << 36) /* * Items in the extent tree are used to record the objectid of the * owner of the block and the number of references. */ struct btrfs_extent_item { __le64 refs; __le64 generation; __le64 flags; } __attribute__ ((__packed__)); struct btrfs_extent_item_v0 { __le32 refs; } __attribute__ ((__packed__)); #define BTRFS_EXTENT_FLAG_DATA (1ULL << 0) #define BTRFS_EXTENT_FLAG_TREE_BLOCK (1ULL << 1) /* Use full backrefs for extent pointers in the block */ #define BTRFS_BLOCK_FLAG_FULL_BACKREF (1ULL << 8) /* * This flag is only used internally by scrub and may be changed at any time * it is only declared here to avoid collisions. */ #define BTRFS_EXTENT_FLAG_SUPER (1ULL << 48) struct btrfs_tree_block_info { struct btrfs_disk_key key; __u8 level; } __attribute__ ((__packed__)); struct btrfs_extent_data_ref { __le64 root; __le64 objectid; __le64 offset; __le32 count; } __attribute__ ((__packed__)); struct btrfs_shared_data_ref { __le32 count; } __attribute__ ((__packed__)); struct btrfs_extent_inline_ref { __u8 type; __le64 offset; } __attribute__ ((__packed__)); /* Old style backrefs item */ struct btrfs_extent_ref_v0 { __le64 root; __le64 generation; __le64 objectid; __le32 count; } __attribute__ ((__packed__)); /* Dev extents record used space on individual devices. * * The owner field points back to the chunk allocation mapping tree that * allocated the extent. * The chunk tree uuid field is a way to double check the owner. */ struct btrfs_dev_extent { __le64 chunk_tree; __le64 chunk_objectid; __le64 chunk_offset; __le64 length; __u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; } __attribute__ ((__packed__)); struct btrfs_inode_ref { __le64 index; __le16 name_len; /* Name goes here */ } __attribute__ ((__packed__)); struct btrfs_inode_extref { __le64 parent_objectid; __le64 index; __le16 name_len; __u8 name[0]; /* Name goes here */ } __attribute__ ((__packed__)); struct btrfs_timespec { __le64 sec; __le32 nsec; } __attribute__ ((__packed__)); /* Inode flags */ #define BTRFS_INODE_NODATASUM (1 << 0) #define BTRFS_INODE_NODATACOW (1 << 1) #define BTRFS_INODE_READONLY (1 << 2) #define BTRFS_INODE_NOCOMPRESS (1 << 3) #define BTRFS_INODE_PREALLOC (1 << 4) #define BTRFS_INODE_SYNC (1 << 5) #define BTRFS_INODE_IMMUTABLE (1 << 6) #define BTRFS_INODE_APPEND (1 << 7) #define BTRFS_INODE_NODUMP (1 << 8) #define BTRFS_INODE_NOATIME (1 << 9) #define BTRFS_INODE_DIRSYNC (1 << 10) #define BTRFS_INODE_COMPRESS (1 << 11) #define BTRFS_INODE_ROOT_ITEM_INIT (1 << 31) #define BTRFS_INODE_FLAG_MASK \ (BTRFS_INODE_NODATASUM | \ BTRFS_INODE_NODATACOW | \ BTRFS_INODE_READONLY | \ BTRFS_INODE_NOCOMPRESS | \ BTRFS_INODE_PREALLOC | \ BTRFS_INODE_SYNC | \ BTRFS_INODE_IMMUTABLE | \ BTRFS_INODE_APPEND | \ BTRFS_INODE_NODUMP | \ BTRFS_INODE_NOATIME | \ BTRFS_INODE_DIRSYNC | \ BTRFS_INODE_COMPRESS | \ BTRFS_INODE_ROOT_ITEM_INIT) struct btrfs_inode_item { /* Nfs style generation number */ __le64 generation; /* Transid that last touched this inode */ __le64 transid; __le64 size; __le64 nbytes; __le64 block_group; __le32 nlink; __le32 uid; __le32 gid; __le32 mode; __le64 rdev; __le64 flags; /* Modification sequence number for NFS */ __le64 sequence; /* * A little future expansion, for more than this we can just grow the * inode item and version it */ __le64 reserved[4]; struct btrfs_timespec atime; struct btrfs_timespec ctime; struct btrfs_timespec mtime; struct btrfs_timespec otime; } __attribute__ ((__packed__)); struct btrfs_dir_log_item { __le64 end; } __attribute__ ((__packed__)); struct btrfs_dir_item { struct btrfs_disk_key location; __le64 transid; __le16 data_len; __le16 name_len; __u8 type; } __attribute__ ((__packed__)); #define BTRFS_ROOT_SUBVOL_RDONLY (1ULL << 0) /* * Internal in-memory flag that a subvolume has been marked for deletion but * still visible as a directory */ #define BTRFS_ROOT_SUBVOL_DEAD (1ULL << 48) struct btrfs_root_item { struct btrfs_inode_item inode; __le64 generation; __le64 root_dirid; __le64 bytenr; __le64 byte_limit; __le64 bytes_used; __le64 last_snapshot; __le64 flags; __le32 refs; struct btrfs_disk_key drop_progress; __u8 drop_level; __u8 level; /* * The following fields appear after subvol_uuids+subvol_times * were introduced. */ /* * This generation number is used to test if the new fields are valid * and up to date while reading the root item. Every time the root item * is written out, the "generation" field is copied into this field. If * anyone ever mounted the fs with an older kernel, we will have * mismatching generation values here and thus must invalidate the * new fields. See btrfs_update_root and btrfs_find_last_root for * details. * The offset of generation_v2 is also used as the start for the memset * when invalidating the fields. */ __le64 generation_v2; __u8 uuid[BTRFS_UUID_SIZE]; __u8 parent_uuid[BTRFS_UUID_SIZE]; __u8 received_uuid[BTRFS_UUID_SIZE]; __le64 ctransid; /* Updated when an inode changes */ __le64 otransid; /* Trans when created */ __le64 stransid; /* Trans when sent. Non-zero for received subvol. */ __le64 rtransid; /* Trans when received. Non-zero for received subvol.*/ struct btrfs_timespec ctime; struct btrfs_timespec otime; struct btrfs_timespec stime; struct btrfs_timespec rtime; __le64 reserved[8]; /* For future */ } __attribute__ ((__packed__)); /* This is used for both forward and backward root refs */ struct btrfs_root_ref { __le64 dirid; __le64 sequence; __le16 name_len; } __attribute__ ((__packed__)); struct btrfs_disk_balance_args { /* * Profiles to operate on. * * SINGLE is denoted by BTRFS_AVAIL_ALLOC_BIT_SINGLE. */ __le64 profiles; /* * Usage filter * BTRFS_BALANCE_ARGS_USAGE with a single value means '0..N' * BTRFS_BALANCE_ARGS_USAGE_RANGE - range syntax, min..max */ union { __le64 usage; struct { __le32 usage_min; __le32 usage_max; }; }; /* Devid filter */ __le64 devid; /* Devid subset filter [pstart..pend) */ __le64 pstart; __le64 pend; /* Btrfs virtual address space subset filter [vstart..vend) */ __le64 vstart; __le64 vend; /* * Profile to convert to. * * SINGLE is denoted by BTRFS_AVAIL_ALLOC_BIT_SINGLE. */ __le64 target; /* BTRFS_BALANCE_ARGS_* */ __le64 flags; /* * BTRFS_BALANCE_ARGS_LIMIT with value 'limit'. * BTRFS_BALANCE_ARGS_LIMIT_RANGE - the extend version can use minimum * and maximum. */ union { __le64 limit; struct { __le32 limit_min; __le32 limit_max; }; }; /* * Process chunks that cross stripes_min..stripes_max devices, * BTRFS_BALANCE_ARGS_STRIPES_RANGE. */ __le32 stripes_min; __le32 stripes_max; __le64 unused[6]; } __attribute__ ((__packed__)); /* * Stores balance parameters to disk so that balance can be properly * resumed after crash or unmount. */ struct btrfs_balance_item { /* BTRFS_BALANCE_* */ __le64 flags; struct btrfs_disk_balance_args data; struct btrfs_disk_balance_args meta; struct btrfs_disk_balance_args sys; __le64 unused[4]; } __attribute__ ((__packed__)); enum { BTRFS_FILE_EXTENT_INLINE = 0, BTRFS_FILE_EXTENT_REG = 1, BTRFS_FILE_EXTENT_PREALLOC = 2, BTRFS_NR_FILE_EXTENT_TYPES = 3, }; enum btrfs_compression_type { BTRFS_COMPRESS_NONE = 0, BTRFS_COMPRESS_ZLIB = 1, BTRFS_COMPRESS_LZO = 2, BTRFS_COMPRESS_ZSTD = 3, BTRFS_NR_COMPRESS_TYPES = 4, }; struct btrfs_file_extent_item { /* Transaction id that created this extent */ __le64 generation; /* * Max number of bytes to hold this extent in ram. * * When we split a compressed extent we can't know how big each of the * resulting pieces will be. So, this is an upper limit on the size of * the extent in ram instead of an exact limit. */ __le64 ram_bytes; /* * 32 bits for the various ways we might encode the data, * including compression and encryption. If any of these * are set to something a given disk format doesn't understand * it is treated like an incompat flag for reading and writing, * but not for stat. */ __u8 compression; __u8 encryption; __le16 other_encoding; /* Spare for later use */ /* Are we inline data or a real extent? */ __u8 type; /* * Disk space consumed by the extent, checksum blocks are not included * in these numbers * * At this offset in the structure, the inline extent data start. */ __le64 disk_bytenr; __le64 disk_num_bytes; /* * The logical offset inside the file extent. * * This allows a file extent to point into the middle of an existing * extent on disk, sharing it between two snapshots (useful if some * bytes in the middle of the extent have changed). */ __le64 offset; /* * The logical number of bytes this file extent is referencing (no * csums included). * * This always reflects the size uncompressed and without encoding. */ __le64 num_bytes; } __attribute__ ((__packed__)); struct btrfs_csum_item { __u8 csum; } __attribute__ ((__packed__)); enum btrfs_dev_stat_values { /* Disk I/O failure stats */ BTRFS_DEV_STAT_WRITE_ERRS, /* EIO or EREMOTEIO from lower layers */ BTRFS_DEV_STAT_READ_ERRS, /* EIO or EREMOTEIO from lower layers */ BTRFS_DEV_STAT_FLUSH_ERRS, /* EIO or EREMOTEIO from lower layers */ /* Stats for indirect indications for I/O failures */ BTRFS_DEV_STAT_CORRUPTION_ERRS, /* Checksum error, bytenr error or * contents is illegal: this is an * indication that the block was damaged * during read or write, or written to * wrong location or read from wrong * location */ BTRFS_DEV_STAT_GENERATION_ERRS, /* An indication that blocks have not * been written */ BTRFS_DEV_STAT_VALUES_MAX }; struct btrfs_dev_stats_item { /* * Grow this item struct at the end for future enhancements and keep * the existing values unchanged. */ __le64 values[BTRFS_DEV_STAT_VALUES_MAX]; } __attribute__ ((__packed__)); #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS 0 #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID 1 struct btrfs_dev_replace_item { /* * Grow this item struct at the end for future enhancements and keep * the existing values unchanged. */ __le64 src_devid; __le64 cursor_left; __le64 cursor_right; __le64 cont_reading_from_srcdev_mode; __le64 replace_state; __le64 time_started; __le64 time_stopped; __le64 num_write_errors; __le64 num_uncorrectable_read_errors; } __attribute__ ((__packed__)); /* Different types of block groups (and chunks) */ #define BTRFS_BLOCK_GROUP_DATA (1ULL << 0) #define BTRFS_BLOCK_GROUP_SYSTEM (1ULL << 1) #define BTRFS_BLOCK_GROUP_METADATA (1ULL << 2) #define BTRFS_BLOCK_GROUP_RAID0 (1ULL << 3) #define BTRFS_BLOCK_GROUP_RAID1 (1ULL << 4) #define BTRFS_BLOCK_GROUP_DUP (1ULL << 5) #define BTRFS_BLOCK_GROUP_RAID10 (1ULL << 6) #define BTRFS_BLOCK_GROUP_RAID5 (1ULL << 7) #define BTRFS_BLOCK_GROUP_RAID6 (1ULL << 8) #define BTRFS_BLOCK_GROUP_RAID1C3 (1ULL << 9) #define BTRFS_BLOCK_GROUP_RAID1C4 (1ULL << 10) #define BTRFS_BLOCK_GROUP_RESERVED (BTRFS_AVAIL_ALLOC_BIT_SINGLE | \ BTRFS_SPACE_INFO_GLOBAL_RSV) enum btrfs_raid_types { BTRFS_RAID_RAID10, BTRFS_RAID_RAID1, BTRFS_RAID_DUP, BTRFS_RAID_RAID0, BTRFS_RAID_SINGLE, BTRFS_RAID_RAID5, BTRFS_RAID_RAID6, BTRFS_RAID_RAID1C3, BTRFS_RAID_RAID1C4, BTRFS_NR_RAID_TYPES }; #define BTRFS_BLOCK_GROUP_TYPE_MASK (BTRFS_BLOCK_GROUP_DATA | \ BTRFS_BLOCK_GROUP_SYSTEM | \ BTRFS_BLOCK_GROUP_METADATA) #define BTRFS_BLOCK_GROUP_PROFILE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \ BTRFS_BLOCK_GROUP_RAID1 | \ BTRFS_BLOCK_GROUP_RAID1C3 | \ BTRFS_BLOCK_GROUP_RAID1C4 | \ BTRFS_BLOCK_GROUP_RAID5 | \ BTRFS_BLOCK_GROUP_RAID6 | \ BTRFS_BLOCK_GROUP_DUP | \ BTRFS_BLOCK_GROUP_RAID10) #define BTRFS_BLOCK_GROUP_RAID56_MASK (BTRFS_BLOCK_GROUP_RAID5 | \ BTRFS_BLOCK_GROUP_RAID6) #define BTRFS_BLOCK_GROUP_RAID1_MASK (BTRFS_BLOCK_GROUP_RAID1 | \ BTRFS_BLOCK_GROUP_RAID1C3 | \ BTRFS_BLOCK_GROUP_RAID1C4) /* * We need a bit for restriper to be able to tell when chunks of type * SINGLE are available. This "extended" profile format is used in * fs_info->avail_*_alloc_bits (in-memory) and balance item fields * (on-disk). The corresponding on-disk bit in chunk.type is reserved * to avoid remappings between two formats in future. */ #define BTRFS_AVAIL_ALLOC_BIT_SINGLE (1ULL << 48) /* * A fake block group type that is used to communicate global block reserve * size to userspace via the SPACE_INFO ioctl. */ #define BTRFS_SPACE_INFO_GLOBAL_RSV (1ULL << 49) #define BTRFS_EXTENDED_PROFILE_MASK (BTRFS_BLOCK_GROUP_PROFILE_MASK | \ BTRFS_AVAIL_ALLOC_BIT_SINGLE) static inline __u64 chunk_to_extended(__u64 flags) { if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0) flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE; return flags; } static inline __u64 extended_to_chunk(__u64 flags) { return flags & ~BTRFS_AVAIL_ALLOC_BIT_SINGLE; } struct btrfs_block_group_item { __le64 used; __le64 chunk_objectid; __le64 flags; } __attribute__ ((__packed__)); struct btrfs_free_space_info { __le32 extent_count; __le32 flags; } __attribute__ ((__packed__)); #define BTRFS_FREE_SPACE_USING_BITMAPS (1ULL << 0) #define BTRFS_QGROUP_LEVEL_SHIFT 48 static inline __u64 btrfs_qgroup_level(__u64 qgroupid) { return qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT; } /* Is subvolume quota turned on? */ #define BTRFS_QGROUP_STATUS_FLAG_ON (1ULL << 0) /* Is qgroup rescan running? */ #define BTRFS_QGROUP_STATUS_FLAG_RESCAN (1ULL << 1) /* * Some qgroup entries are known to be out of date, either because the * configuration has changed in a way that makes a rescan necessary, or * because the fs has been mounted with a non-qgroup-aware version. */ #define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT (1ULL << 2) #define BTRFS_QGROUP_STATUS_VERSION 1 struct btrfs_qgroup_status_item { __le64 version; /* * The generation is updated during every commit. As older * versions of btrfs are not aware of qgroups, it will be * possible to detect inconsistencies by checking the * generation on mount time. */ __le64 generation; /* Flag definitions see above */ __le64 flags; /* * Only used during scanning to record the progress of the scan. * It contains a logical address. */ __le64 rescan; } __attribute__ ((__packed__)); struct btrfs_qgroup_info_item { __le64 generation; __le64 rfer; __le64 rfer_cmpr; __le64 excl; __le64 excl_cmpr; } __attribute__ ((__packed__)); /* * Flags definition for qgroup limits * * Used by: * struct btrfs_qgroup_limit.flags * struct btrfs_qgroup_limit_item.flags */ #define BTRFS_QGROUP_LIMIT_MAX_RFER (1ULL << 0) #define BTRFS_QGROUP_LIMIT_MAX_EXCL (1ULL << 1) #define BTRFS_QGROUP_LIMIT_RSV_RFER (1ULL << 2) #define BTRFS_QGROUP_LIMIT_RSV_EXCL (1ULL << 3) #define BTRFS_QGROUP_LIMIT_RFER_CMPR (1ULL << 4) #define BTRFS_QGROUP_LIMIT_EXCL_CMPR (1ULL << 5) struct btrfs_qgroup_limit_item { /* Only updated when any of the other values change. */ __le64 flags; __le64 max_rfer; __le64 max_excl; __le64 rsv_rfer; __le64 rsv_excl; } __attribute__ ((__packed__)); /* * Just in case we somehow lose the roots and are not able to mount, * we store an array of the roots from previous transactions in the super. */ #define BTRFS_NUM_BACKUP_ROOTS 4 struct btrfs_root_backup { __le64 tree_root; __le64 tree_root_gen; __le64 chunk_root; __le64 chunk_root_gen; __le64 extent_root; __le64 extent_root_gen; __le64 fs_root; __le64 fs_root_gen; __le64 dev_root; __le64 dev_root_gen; __le64 csum_root; __le64 csum_root_gen; __le64 total_bytes; __le64 bytes_used; __le64 num_devices; /* future */ __le64 unused_64[4]; u8 tree_root_level; u8 chunk_root_level; u8 extent_root_level; u8 fs_root_level; u8 dev_root_level; u8 csum_root_level; /* future and to align */ u8 unused_8[10]; } __attribute__ ((__packed__)); /* * This is a very generous portion of the super block, giving us room to * translate 14 chunks with 3 stripes each. */ #define BTRFS_SYSTEM_CHUNK_ARRAY_SIZE 2048 #define BTRFS_LABEL_SIZE 256 /* The super block basically lists the main trees of the FS. */ struct btrfs_super_block { /* The first 4 fields must match struct btrfs_header */ u8 csum[BTRFS_CSUM_SIZE]; /* FS specific UUID, visible to user */ u8 fsid[BTRFS_FSID_SIZE]; __le64 bytenr; /* this block number */ __le64 flags; /* Allowed to be different from the btrfs_header from here own down. */ __le64 magic; __le64 generation; __le64 root; __le64 chunk_root; __le64 log_root; /* This will help find the new super based on the log root. */ __le64 log_root_transid; __le64 total_bytes; __le64 bytes_used; __le64 root_dir_objectid; __le64 num_devices; __le32 sectorsize; __le32 nodesize; __le32 __unused_leafsize; __le32 stripesize; __le32 sys_chunk_array_size; __le64 chunk_root_generation; __le64 compat_flags; __le64 compat_ro_flags; __le64 incompat_flags; __le16 csum_type; u8 root_level; u8 chunk_root_level; u8 log_root_level; struct btrfs_dev_item dev_item; char label[BTRFS_LABEL_SIZE]; __le64 cache_generation; __le64 uuid_tree_generation; /* The UUID written into btree blocks */ u8 metadata_uuid[BTRFS_FSID_SIZE]; /* Future expansion */ __le64 reserved[28]; u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE]; struct btrfs_root_backup super_roots[BTRFS_NUM_BACKUP_ROOTS]; } __attribute__ ((__packed__)); /* * Feature flags * * Used by: * struct btrfs_super_block::(compat|compat_ro|incompat)_flags * struct btrfs_ioctl_feature_flags */ #define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE (1ULL << 0) /* * Older kernels (< 4.9) on big-endian systems produced broken free space tree * bitmaps, and btrfs-progs also used to corrupt the free space tree (versions * < 4.7.3). If this bit is clear, then the free space tree cannot be trusted. * btrfs-progs can also intentionally clear this bit to ask the kernel to * rebuild the free space tree, however this might not work on older kernels * that do not know about this bit. If not sure, clear the cache manually on * first mount when booting older kernel versions. */ #define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID (1ULL << 1) #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF (1ULL << 0) #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL (1ULL << 1) #define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS (1ULL << 2) #define BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO (1ULL << 3) #define BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD (1ULL << 4) /* * Older kernels tried to do bigger metadata blocks, but the * code was pretty buggy. Lets not let them try anymore. */ #define BTRFS_FEATURE_INCOMPAT_BIG_METADATA (1ULL << 5) #define BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF (1ULL << 6) #define BTRFS_FEATURE_INCOMPAT_RAID56 (1ULL << 7) #define BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA (1ULL << 8) #define BTRFS_FEATURE_INCOMPAT_NO_HOLES (1ULL << 9) #define BTRFS_FEATURE_INCOMPAT_METADATA_UUID (1ULL << 10) #define BTRFS_FEATURE_INCOMPAT_RAID1C34 (1ULL << 11) /* * Compat flags that we support. * * If any incompat flags are set other than the ones specified below then we * will fail to mount. */ #define BTRFS_FEATURE_COMPAT_SUPP 0ULL #define BTRFS_FEATURE_COMPAT_SAFE_SET 0ULL #define BTRFS_FEATURE_COMPAT_SAFE_CLEAR 0ULL #define BTRFS_FEATURE_COMPAT_RO_SUPP \ (BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE | \ BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID) #define BTRFS_FEATURE_COMPAT_RO_SAFE_SET 0ULL #define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR 0ULL #define BTRFS_FEATURE_INCOMPAT_SUPP \ (BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF | \ BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL | \ BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS | \ BTRFS_FEATURE_INCOMPAT_BIG_METADATA | \ BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO | \ BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD | \ BTRFS_FEATURE_INCOMPAT_RAID56 | \ BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF | \ BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA | \ BTRFS_FEATURE_INCOMPAT_NO_HOLES | \ BTRFS_FEATURE_INCOMPAT_METADATA_UUID | \ BTRFS_FEATURE_INCOMPAT_RAID1C34) #define BTRFS_FEATURE_INCOMPAT_SAFE_SET \ (BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF) #define BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR 0ULL #define BTRFS_BACKREF_REV_MAX 256 #define BTRFS_BACKREF_REV_SHIFT 56 #define BTRFS_BACKREF_REV_MASK (((u64)BTRFS_BACKREF_REV_MAX - 1) << \ BTRFS_BACKREF_REV_SHIFT) #define BTRFS_OLD_BACKREF_REV 0 #define BTRFS_MIXED_BACKREF_REV 1 #define BTRFS_MAX_LEVEL 8 /* Every tree block (leaf or node) starts with this header. */ struct btrfs_header { /* These first four must match the super block */ u8 csum[BTRFS_CSUM_SIZE]; u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */ __le64 bytenr; /* Which block this node is supposed to live in */ __le64 flags; /* Allowed to be different from the super from here on down. */ u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; __le64 generation; __le64 owner; __le32 nritems; u8 level; } __attribute__ ((__packed__)); /* * A leaf is full of items. Offset and size tell us where to find * the item in the leaf (relative to the start of the data area). */ struct btrfs_item { struct btrfs_disk_key key; __le32 offset; __le32 size; } __attribute__ ((__packed__)); /* * leaves have an item area and a data area: * [item0, item1....itemN] [free space] [dataN...data1, data0] * * The data is separate from the items to get the keys closer together * during searches. */ struct btrfs_leaf { struct btrfs_header header; struct btrfs_item items[]; } __attribute__ ((__packed__)); /* * All non-leaf blocks are nodes, they hold only keys and pointers to children * blocks. */ struct btrfs_key_ptr { struct btrfs_disk_key key; __le64 blockptr; __le64 generation; } __attribute__ ((__packed__)); struct btrfs_node { struct btrfs_header header; struct btrfs_key_ptr ptrs[]; } __attribute__ ((__packed__)); #endif /* __BTRFS_TREE_H__ */