/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef _BTRFS_CTREE_H_ #define _BTRFS_CTREE_H_ #include <linux/btrfs.h> #include <linux/types.h> #ifdef __KERNEL__ #include <linux/stddef.h> #else #include <stddef.h> #endif /* ASCII for _BHRfS_M, no terminating nul */ #define BTRFS_MAGIC … #define BTRFS_MAX_LEVEL … /* * We can actually store much bigger names, but lets not confuse the rest of * linux. */ #define BTRFS_NAME_LEN … /* * Theoretical limit is larger, but we keep this down to a sane value. That * should limit greatly the possibility of collisions on inode ref items. */ #define BTRFS_LINK_MAX … /* * This header contains the structure definitions and constants used * by file system objects that can be retrieved using * the BTRFS_IOC_SEARCH_TREE ioctl. That means basically anything that * is needed to describe a leaf node's key or item contents. */ /* holds pointers to all of the tree roots */ #define BTRFS_ROOT_TREE_OBJECTID … /* stores information about which extents are in use, and reference counts */ #define BTRFS_EXTENT_TREE_OBJECTID … /* * chunk tree stores translations from logical -> physical block numbering * the super block points to the chunk tree */ #define BTRFS_CHUNK_TREE_OBJECTID … /* * stores information about which areas of a given device are in use. * one per device. The tree of tree roots points to the device tree */ #define BTRFS_DEV_TREE_OBJECTID … /* one per subvolume, storing files and directories */ #define BTRFS_FS_TREE_OBJECTID … /* directory objectid inside the root tree */ #define BTRFS_ROOT_TREE_DIR_OBJECTID … /* holds checksums of all the data extents */ #define BTRFS_CSUM_TREE_OBJECTID … /* holds quota configuration and tracking */ #define BTRFS_QUOTA_TREE_OBJECTID … /* for storing items that use the BTRFS_UUID_KEY* types */ #define BTRFS_UUID_TREE_OBJECTID … /* tracks free space in block groups. */ #define BTRFS_FREE_SPACE_TREE_OBJECTID … /* Holds the block group items for extent tree v2. */ #define BTRFS_BLOCK_GROUP_TREE_OBJECTID … /* Tracks RAID stripes in block groups. */ #define BTRFS_RAID_STRIPE_TREE_OBJECTID … /* device stats in the device tree */ #define BTRFS_DEV_STATS_OBJECTID … /* for storing balance parameters in the root tree */ #define BTRFS_BALANCE_OBJECTID … /* orphan objectid for tracking unlinked/truncated files */ #define BTRFS_ORPHAN_OBJECTID … /* does write ahead logging to speed up fsyncs */ #define BTRFS_TREE_LOG_OBJECTID … #define BTRFS_TREE_LOG_FIXUP_OBJECTID … /* for space balancing */ #define BTRFS_TREE_RELOC_OBJECTID … #define BTRFS_DATA_RELOC_TREE_OBJECTID … /* * extent checksums all have this objectid * this allows them to share the logging tree * for fsyncs */ #define BTRFS_EXTENT_CSUM_OBJECTID … /* For storing free space cache */ #define BTRFS_FREE_SPACE_OBJECTID … /* * The inode number assigned to the special inode for storing * free ino cache */ #define BTRFS_FREE_INO_OBJECTID … /* dummy objectid represents multiple objectids */ #define BTRFS_MULTIPLE_OBJECTIDS … /* * All files have objectids in this range. */ #define BTRFS_FIRST_FREE_OBJECTID … #define BTRFS_LAST_FREE_OBJECTID … #define BTRFS_FIRST_CHUNK_TREE_OBJECTID … /* * the device items go into the chunk tree. The key is in the form * [ 1 BTRFS_DEV_ITEM_KEY device_id ] */ #define BTRFS_DEV_ITEMS_OBJECTID … #define BTRFS_BTREE_INODE_OBJECTID … #define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID … #define BTRFS_DEV_REPLACE_DEVID … /* * 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 … #define BTRFS_INODE_REF_KEY … #define BTRFS_INODE_EXTREF_KEY … #define BTRFS_XATTR_ITEM_KEY … /* * fs verity items are stored under two different key types on disk. * The descriptor items: * [ inode objectid, BTRFS_VERITY_DESC_ITEM_KEY, offset ] * * At offset 0, we store a btrfs_verity_descriptor_item which tracks the size * of the descriptor item and some extra data for encryption. * Starting at offset 1, these hold the generic fs verity descriptor. The * latter are opaque to btrfs, we just read and write them as a blob for the * higher level verity code. The most common descriptor size is 256 bytes. * * The merkle tree items: * [ inode objectid, BTRFS_VERITY_MERKLE_ITEM_KEY, offset ] * * These also start at offset 0, and correspond to the merkle tree bytes. When * fsverity asks for page 0 of the merkle tree, we pull up one page starting at * offset 0 for this key type. These are also opaque to btrfs, we're blindly * storing whatever fsverity sends down. */ #define BTRFS_VERITY_DESC_ITEM_KEY … #define BTRFS_VERITY_MERKLE_ITEM_KEY … #define BTRFS_ORPHAN_ITEM_KEY … /* reserve 2-15 close to the inode for later flexibility */ /* * dir items are the name -> inode pointers in a directory. There is one * for every name in a directory. BTRFS_DIR_LOG_ITEM_KEY is no longer used * but it's still defined here for documentation purposes and to help avoid * having its numerical value reused in the future. */ #define BTRFS_DIR_LOG_ITEM_KEY … #define BTRFS_DIR_LOG_INDEX_KEY … #define BTRFS_DIR_ITEM_KEY … #define BTRFS_DIR_INDEX_KEY … /* * extent data is for file data */ #define BTRFS_EXTENT_DATA_KEY … /* * extent csums are stored in a separate tree and hold csums for * an entire extent on disk. */ #define BTRFS_EXTENT_CSUM_KEY … /* * 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 … /* * root backrefs tie subvols and snapshots to the directory entries that * reference them */ #define BTRFS_ROOT_BACKREF_KEY … /* * 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 … /* * extent items are in the extent map tree. These record which blocks * are used, and how many references there are to each block */ #define BTRFS_EXTENT_ITEM_KEY … /* * 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 … /* * Special inline ref key which stores the id of the subvolume which originally * created the extent. This subvolume owns the extent permanently from the * perspective of simple quotas. Needed to know which subvolume to free quota * usage from when the extent is deleted. * * Stored as an inline ref rather to avoid wasting space on a separate item on * top of the existing extent item. However, unlike the other inline refs, * there is one one owner ref per extent rather than one per extent. * * Because of this, it goes at the front of the list of inline refs, and thus * must have a lower type value than any other inline ref type (to satisfy the * disk format rule that inline refs have non-decreasing type). */ #define BTRFS_EXTENT_OWNER_REF_KEY … #define BTRFS_TREE_BLOCK_REF_KEY … #define BTRFS_EXTENT_DATA_REF_KEY … /* * Obsolete key. Defintion removed in 6.6, value may be reused in the future. * * #define BTRFS_EXTENT_REF_V0_KEY 180 */ #define BTRFS_SHARED_BLOCK_REF_KEY … #define BTRFS_SHARED_DATA_REF_KEY … /* * block groups give us hints into the extent allocation trees. Which * blocks are free etc etc */ #define BTRFS_BLOCK_GROUP_ITEM_KEY … /* * 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 … /* * 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 … /* * 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 … #define BTRFS_DEV_EXTENT_KEY … #define BTRFS_DEV_ITEM_KEY … #define BTRFS_CHUNK_ITEM_KEY … #define BTRFS_RAID_STRIPE_KEY … /* * 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 … /* * Records the currently used space of the qgroup. * One key per qgroup, (0, BTRFS_QGROUP_INFO_KEY, qgroupid). */ #define BTRFS_QGROUP_INFO_KEY … /* * Contains the user configured limits for the qgroup. * One key per qgroup, (0, BTRFS_QGROUP_LIMIT_KEY, qgroupid). */ #define BTRFS_QGROUP_LIMIT_KEY … /* * 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 … /* * Obsolete name, see BTRFS_TEMPORARY_ITEM_KEY. */ #define BTRFS_BALANCE_ITEM_KEY … /* * 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 … /* * Obsolete name, see BTRFS_PERSISTENT_ITEM_KEY */ #define BTRFS_DEV_STATS_KEY … /* * 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 … /* * 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 … /* * 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). */ #if BTRFS_UUID_SIZE != 16 #error "UUID items require BTRFS_UUID_SIZE == 16!" #endif #define BTRFS_UUID_KEY_SUBVOL … #define BTRFS_UUID_KEY_RECEIVED_SUBVOL … /* * string items are for debugging. They just store a short string of * data in the FS */ #define BTRFS_STRING_ITEM_KEY … /* Maximum metadata block size (nodesize) */ #define BTRFS_MAX_METADATA_BLOCKSIZE … /* 32 bytes in various csum fields */ #define BTRFS_CSUM_SIZE … /* csum types */ enum btrfs_csum_type { … }; /* * 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 … #define BTRFS_FT_REG_FILE … #define BTRFS_FT_DIR … #define BTRFS_FT_CHRDEV … #define BTRFS_FT_BLKDEV … #define BTRFS_FT_FIFO … #define BTRFS_FT_SOCK … #define BTRFS_FT_SYMLINK … #define BTRFS_FT_XATTR … #define BTRFS_FT_MAX … /* Directory contains encrypted data */ #define BTRFS_FT_ENCRYPTED … static inline __u8 btrfs_dir_flags_to_ftype(__u8 flags) { … } /* * Inode flags */ #define BTRFS_INODE_NODATASUM … #define BTRFS_INODE_NODATACOW … #define BTRFS_INODE_READONLY … #define BTRFS_INODE_NOCOMPRESS … #define BTRFS_INODE_PREALLOC … #define BTRFS_INODE_SYNC … #define BTRFS_INODE_IMMUTABLE … #define BTRFS_INODE_APPEND … #define BTRFS_INODE_NODUMP … #define BTRFS_INODE_NOATIME … #define BTRFS_INODE_DIRSYNC … #define BTRFS_INODE_COMPRESS … #define BTRFS_INODE_ROOT_ITEM_INIT … #define BTRFS_INODE_FLAG_MASK … #define BTRFS_INODE_RO_VERITY … #define BTRFS_INODE_RO_FLAG_MASK … /* * The key defines the order in the tree, and so it also defines (optimal) * block layout. * * objectid corresponds to the inode number. * * type tells us things about the object, and is a kind of stream selector. * so for a given inode, keys with type of 1 might refer to the inode data, * type of 2 may point to file data in the btree and type == 3 may point to * extents. * * offset is the starting byte offset for this key in the stream. * * 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 { … } __attribute__ ((packed)); struct btrfs_key { … } __attribute__ ((packed)); /* * Every tree block (leaf or node) starts with this header. */ struct btrfs_header { … } __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 … /* * 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 … struct btrfs_root_backup { … } __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 { … } __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 { … } __attribute__ ((packed)); /* * All non-leaf blocks are nodes, they hold only keys and pointers to other * blocks. */ struct btrfs_key_ptr { … } __attribute__ ((packed)); struct btrfs_node { … } __attribute__ ((packed)); struct btrfs_dev_item { … } __attribute__ ((packed)); struct btrfs_stripe { … } __attribute__ ((packed)); struct btrfs_chunk { … } __attribute__ ((packed)); /* * The super block basically lists the main trees of the FS. */ struct btrfs_super_block { … } __attribute__ ((packed)); #define BTRFS_FREE_SPACE_EXTENT … #define BTRFS_FREE_SPACE_BITMAP … struct btrfs_free_space_entry { … } __attribute__ ((packed)); struct btrfs_free_space_header { … } __attribute__ ((packed)); struct btrfs_raid_stride { … } __attribute__ ((packed)); struct btrfs_stripe_extent { … } __attribute__ ((packed)); #define BTRFS_HEADER_FLAG_WRITTEN … #define BTRFS_HEADER_FLAG_RELOC … /* Super block flags */ /* Errors detected */ #define BTRFS_SUPER_FLAG_ERROR … #define BTRFS_SUPER_FLAG_SEEDING … #define BTRFS_SUPER_FLAG_METADUMP … #define BTRFS_SUPER_FLAG_METADUMP_V2 … #define BTRFS_SUPER_FLAG_CHANGING_FSID … #define BTRFS_SUPER_FLAG_CHANGING_FSID_V2 … /* * Those are temporaray flags utilized by btrfs-progs to do offline conversion. * They are rejected by kernel. * But still keep them all here to avoid conflicts. */ #define BTRFS_SUPER_FLAG_CHANGING_BG_TREE … #define BTRFS_SUPER_FLAG_CHANGING_DATA_CSUM … #define BTRFS_SUPER_FLAG_CHANGING_META_CSUM … /* * items in the extent btree are used to record the objectid of the * owner of the block and the number of references */ struct btrfs_extent_item { … } __attribute__ ((packed)); struct btrfs_extent_item_v0 { … } __attribute__ ((packed)); #define BTRFS_EXTENT_FLAG_DATA … #define BTRFS_EXTENT_FLAG_TREE_BLOCK … /* following flags only apply to tree blocks */ /* use full backrefs for extent pointers in the block */ #define BTRFS_BLOCK_FLAG_FULL_BACKREF … #define BTRFS_BACKREF_REV_MAX … #define BTRFS_BACKREF_REV_SHIFT … #define BTRFS_BACKREF_REV_MASK … #define BTRFS_OLD_BACKREF_REV … #define BTRFS_MIXED_BACKREF_REV … /* * 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 … struct btrfs_tree_block_info { … } __attribute__ ((packed)); struct btrfs_extent_data_ref { … } __attribute__ ((packed)); struct btrfs_shared_data_ref { … } __attribute__ ((packed)); struct btrfs_extent_owner_ref { … } __attribute__ ((packed)); struct btrfs_extent_inline_ref { … } __attribute__ ((packed)); /* dev extents record free 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 { … } __attribute__ ((packed)); struct btrfs_inode_ref { … } __attribute__ ((packed)); struct btrfs_inode_extref { … } __attribute__ ((packed)); struct btrfs_timespec { … } __attribute__ ((packed)); struct btrfs_inode_item { … } __attribute__ ((packed)); struct btrfs_dir_log_item { … } __attribute__ ((packed)); struct btrfs_dir_item { … } __attribute__ ((packed)); #define BTRFS_ROOT_SUBVOL_RDONLY … /* * Internal in-memory flag that a subvolume has been marked for deletion but * still visible as a directory */ #define BTRFS_ROOT_SUBVOL_DEAD … struct btrfs_root_item { … } __attribute__ ((packed)); /* * Btrfs root item used to be smaller than current size. The old format ends * at where member generation_v2 is. */ static inline __u32 btrfs_legacy_root_item_size(void) { … } /* * this is used for both forward and backward root refs */ struct btrfs_root_ref { … } __attribute__ ((packed)); struct btrfs_disk_balance_args { … } __attribute__ ((packed)); /* * store balance parameters to disk so that balance can be properly * resumed after crash or unmount */ struct btrfs_balance_item { … } __attribute__ ((packed)); enum { … }; struct btrfs_file_extent_item { … } __attribute__ ((packed)); struct btrfs_csum_item { … } __attribute__ ((packed)); struct btrfs_dev_stats_item { … } __attribute__ ((packed)); #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS … #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID … struct btrfs_dev_replace_item { … } __attribute__ ((packed)); /* different types of block groups (and chunks) */ #define BTRFS_BLOCK_GROUP_DATA … #define BTRFS_BLOCK_GROUP_SYSTEM … #define BTRFS_BLOCK_GROUP_METADATA … #define BTRFS_BLOCK_GROUP_RAID0 … #define BTRFS_BLOCK_GROUP_RAID1 … #define BTRFS_BLOCK_GROUP_DUP … #define BTRFS_BLOCK_GROUP_RAID10 … #define BTRFS_BLOCK_GROUP_RAID5 … #define BTRFS_BLOCK_GROUP_RAID6 … #define BTRFS_BLOCK_GROUP_RAID1C3 … #define BTRFS_BLOCK_GROUP_RAID1C4 … #define BTRFS_BLOCK_GROUP_RESERVED … #define BTRFS_BLOCK_GROUP_TYPE_MASK … #define BTRFS_BLOCK_GROUP_PROFILE_MASK … #define BTRFS_BLOCK_GROUP_RAID56_MASK … #define BTRFS_BLOCK_GROUP_RAID1_MASK … /* * 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 … /* * 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 … #define BTRFS_EXTENDED_PROFILE_MASK … static inline __u64 chunk_to_extended(__u64 flags) { … } static inline __u64 extended_to_chunk(__u64 flags) { … } struct btrfs_block_group_item { … } __attribute__ ((packed)); struct btrfs_free_space_info { … } __attribute__ ((packed)); #define BTRFS_FREE_SPACE_USING_BITMAPS … #define BTRFS_QGROUP_LEVEL_SHIFT … static inline __u16 btrfs_qgroup_level(__u64 qgroupid) { … } /* * is subvolume quota turned on? */ #define BTRFS_QGROUP_STATUS_FLAG_ON … /* * RESCAN is set during the initialization phase */ #define BTRFS_QGROUP_STATUS_FLAG_RESCAN … /* * 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. * Turning qouta off and on again makes it inconsistent, too. */ #define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT … /* * Whether or not this filesystem is using simple quotas. Not exactly the * incompat bit, because we support using simple quotas, disabling it, then * going back to full qgroup quotas. */ #define BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE … #define BTRFS_QGROUP_STATUS_FLAGS_MASK … #define BTRFS_QGROUP_STATUS_VERSION … struct btrfs_qgroup_status_item { … } __attribute__ ((packed)); struct btrfs_qgroup_info_item { … } __attribute__ ((packed)); struct btrfs_qgroup_limit_item { … } __attribute__ ((packed)); struct btrfs_verity_descriptor_item { … } __attribute__ ((packed)); #endif /* _BTRFS_CTREE_H_ */
Codebase Browser
linux