diff options
Diffstat (limited to 'linux-headers/include/linux/btrfs_tree.h')
| -rw-r--r-- | linux-headers/include/linux/btrfs_tree.h | 309 |
1 files changed, 290 insertions, 19 deletions
diff --git a/linux-headers/include/linux/btrfs_tree.h b/linux-headers/include/linux/btrfs_tree.h index d9a890d..46b4084 100644 --- a/linux-headers/include/linux/btrfs_tree.h +++ b/linux-headers/include/linux/btrfs_tree.h @@ -6,6 +6,23 @@ #include <linux/types.h> #include <stddef.h> +/* ASCII for _BHRfS_M, no terminating nul */ +#define BTRFS_MAGIC 0x4D5F53665248425FULL + +#define BTRFS_MAX_LEVEL 8 + +/* + * We can actually store much bigger names, but lets not confuse the rest of + * linux. + */ +#define BTRFS_NAME_LEN 255 + +/* + * 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 65535U + /* * This header contains the structure definitions and constants used * by file system objects that can be retrieved using @@ -49,13 +66,16 @@ /* tracks free space in block groups. */ #define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL +/* Holds the block group items for extent tree v2. */ +#define BTRFS_BLOCK_GROUP_TREE_OBJECTID 11ULL + /* 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 */ +/* orphan objectid for tracking unlinked/truncated files */ #define BTRFS_ORPHAN_OBJECTID -5ULL /* does write ahead logging to speed up fsyncs */ @@ -114,12 +134,37 @@ #define BTRFS_INODE_REF_KEY 12 #define BTRFS_INODE_EXTREF_KEY 13 #define BTRFS_XATTR_ITEM_KEY 24 + +/* + * 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 36 +#define BTRFS_VERITY_MERKLE_ITEM_KEY 37 + #define BTRFS_ORPHAN_ITEM_KEY 48 /* 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. + * 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 60 #define BTRFS_DIR_LOG_INDEX_KEY 72 @@ -171,7 +216,11 @@ #define BTRFS_EXTENT_DATA_REF_KEY 178 -#define BTRFS_EXTENT_REF_V0_KEY 180 +/* + * 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 182 @@ -271,7 +320,7 @@ #define BTRFS_PERSISTENT_ITEM_KEY 249 /* - * Persistantly stores the device replace state in the device tree. + * 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 @@ -295,7 +344,8 @@ */ #define BTRFS_STRING_ITEM_KEY 253 - +/* Maximum metadata block size (nodesize) */ +#define BTRFS_MAX_METADATA_BLOCKSIZE 65536 /* 32 bytes in various csum fields */ #define BTRFS_CSUM_SIZE 32 @@ -326,6 +376,50 @@ enum btrfs_csum_type { #define BTRFS_FT_SYMLINK 7 #define BTRFS_FT_XATTR 8 #define BTRFS_FT_MAX 9 +/* Directory contains encrypted data */ +#define BTRFS_FT_ENCRYPTED 0x80 + +static __inline__ __u8 btrfs_dir_flags_to_ftype(__u8 flags) +{ + return flags & ~BTRFS_FT_ENCRYPTED; +} + +/* + * Inode flags + */ +#define BTRFS_INODE_NODATASUM (1U << 0) +#define BTRFS_INODE_NODATACOW (1U << 1) +#define BTRFS_INODE_READONLY (1U << 2) +#define BTRFS_INODE_NOCOMPRESS (1U << 3) +#define BTRFS_INODE_PREALLOC (1U << 4) +#define BTRFS_INODE_SYNC (1U << 5) +#define BTRFS_INODE_IMMUTABLE (1U << 6) +#define BTRFS_INODE_APPEND (1U << 7) +#define BTRFS_INODE_NODUMP (1U << 8) +#define BTRFS_INODE_NOATIME (1U << 9) +#define BTRFS_INODE_DIRSYNC (1U << 10) +#define BTRFS_INODE_COMPRESS (1U << 11) + +#define BTRFS_INODE_ROOT_ITEM_INIT (1U << 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) + +#define BTRFS_INODE_RO_VERITY (1U << 0) + +#define BTRFS_INODE_RO_FLAG_MASK (BTRFS_INODE_RO_VERITY) /* * The key defines the order in the tree, and so it also defines (optimal) @@ -356,6 +450,109 @@ struct btrfs_key { __u64 offset; } __attribute__ ((__packed__)); +/* + * 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]; + /* FS specific uuid */ + __u8 fsid[BTRFS_FSID_SIZE]; + /* Which block this node is supposed to live in */ + __le64 bytenr; + __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__)); + +/* + * 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 + +/* + * 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__)); + +/* + * 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 other + * 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__)); + struct btrfs_dev_item { /* the internal btrfs device id */ __le64 devid; @@ -439,6 +636,69 @@ struct btrfs_chunk { /* additional stripes go here */ } __attribute__ ((__packed__)); +/* + * 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]; + /* This block number */ + __le64 bytenr; + __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 member has never been utilized since the very beginning, thus + * it's always 0 regardless of kernel version. We always use + * generation + 1 to read log tree root. So here we mark it deprecated. + */ + __le64 __unused_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]; + + __u64 nr_global_roots; + + /* Future expansion */ + __le64 reserved[27]; + __u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE]; + struct btrfs_root_backup super_roots[BTRFS_NUM_BACKUP_ROOTS]; + + /* Padded to 4096 bytes */ + __u8 padding[565]; +} __attribute__ ((__packed__)); + #define BTRFS_FREE_SPACE_EXTENT 1 #define BTRFS_FREE_SPACE_BITMAP 2 @@ -493,6 +753,14 @@ struct btrfs_extent_item_v0 { /* use full backrefs for extent pointers in the block */ #define BTRFS_BLOCK_FLAG_FULL_BACKREF (1ULL << 8) +#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 + /* * this flag is only used internally by scrub and may be changed at any time * it is only declared here to avoid collisions @@ -542,7 +810,7 @@ struct btrfs_inode_extref { __le64 parent_objectid; __le64 index; __le16 name_len; - __u8 name[0]; + __u8 name[]; /* name goes here */ } __attribute__ ((__packed__)); @@ -847,19 +1115,6 @@ struct btrfs_dev_replace_item { #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) @@ -945,6 +1200,10 @@ static __inline__ __u16 btrfs_qgroup_level(__u64 qgroupid) */ #define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT (1ULL << 2) +#define BTRFS_QGROUP_STATUS_FLAGS_MASK (BTRFS_QGROUP_STATUS_FLAG_ON | \ + BTRFS_QGROUP_STATUS_FLAG_RESCAN | \ + BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) + #define BTRFS_QGROUP_STATUS_VERSION 1 struct btrfs_qgroup_status_item { @@ -986,4 +1245,16 @@ struct btrfs_qgroup_limit_item { __le64 rsv_excl; } __attribute__ ((__packed__)); +struct btrfs_verity_descriptor_item { + /* Size of the verity descriptor in bytes */ + __le64 size; + /* + * When we implement support for fscrypt, we will need to encrypt the + * Merkle tree for encrypted verity files. These 128 bits are for the + * eventual storage of an fscrypt initialization vector. + */ + __le64 reserved[2]; + __u8 encryption; +} __attribute__ ((__packed__)); + #endif /* _BTRFS_CTREE_H_ */ |