From: Qu Wenruo Date: Wed, 24 Jun 2020 16:02:47 +0000 (+0200) Subject: fs: btrfs: Sync btrfs_btree.h from kernel X-Git-Url: http://git.dujemihanovic.xyz/?a=commitdiff_plain;h=3b4b40c0d6c02c9a4adc684cf125f628651caf4c;p=u-boot.git fs: btrfs: Sync btrfs_btree.h from kernel This version includes all needed on-disk format from kernel. Only need to modify the include headers for U-Boot, everything else is untouched. Also, since U-Boot btrfs is using a different endian convert timing (at tree block read time), it needs some forced type conversion before proper crossport. Signed-off-by: Qu Wenruo Reviewed-by: Marek Behún --- diff --git a/fs/btrfs/btrfs.c b/fs/btrfs/btrfs.c index de16217d0d..9f2888bab3 100644 --- a/fs/btrfs/btrfs.c +++ b/fs/btrfs/btrfs.c @@ -32,7 +32,8 @@ static int readdir_callback(const struct btrfs_root *root, char filetime[32], *target = NULL; time_t mtime; - if (btrfs_lookup_inode(root, &item->location, &inode, NULL)) { + if (btrfs_lookup_inode(root, (struct btrfs_key *)&item->location, + &inode, NULL)) { printf("%s: Cannot find inode item for directory entry %.*s!\n", __func__, item->name_len, name); return 0; diff --git a/fs/btrfs/btrfs_tree.h b/fs/btrfs/btrfs_tree.h deleted file mode 100644 index aa0f3d6c86..0000000000 --- a/fs/btrfs/btrfs_tree.h +++ /dev/null @@ -1,766 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0+ */ -/* - * From linux/include/uapi/linux/btrfs_tree.h - */ - -#ifndef __BTRFS_BTRFS_TREE_H__ -#define __BTRFS_BTRFS_TREE_H__ - -#include - -#define BTRFS_VOL_NAME_MAX 255 -#define BTRFS_NAME_MAX 255 -#define BTRFS_LABEL_SIZE 256 -#define BTRFS_FSID_SIZE 16 -#define BTRFS_UUID_SIZE 16 - -/* - * 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 1ULL - -/* stores information about which extents are in use, and reference counts */ -#define BTRFS_EXTENT_TREE_OBJECTID 2ULL - -/* - * chunk tree stores translations from logical -> physical block numbering - * the super block points to the chunk tree - */ -#define BTRFS_CHUNK_TREE_OBJECTID 3ULL - -/* - * 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 4ULL - -/* one per subvolume, storing files and directories */ -#define BTRFS_FS_TREE_OBJECTID 5ULL - -/* directory objectid inside the root tree */ -#define BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL - -/* holds checksums of all the data extents */ -#define BTRFS_CSUM_TREE_OBJECTID 7ULL - -/* holds quota configuration and tracking */ -#define BTRFS_QUOTA_TREE_OBJECTID 8ULL - -/* for storing items that use the BTRFS_UUID_KEY* types */ -#define BTRFS_UUID_TREE_OBJECTID 9ULL - -/* tracks free space in block groups. */ -#define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL - -/* 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 all have this objectid - * this allows them to share the logging tree - * for fsyncs - */ -#define BTRFS_EXTENT_CSUM_OBJECTID -10ULL - -/* For storing free 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 - * [ 1 BTRFS_DEV_ITEM_KEY device_id ] - */ -#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 - -/* - * 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 -#define BTRFS_INODE_REF_KEY 12 -#define BTRFS_INODE_EXTREF_KEY 13 -#define BTRFS_XATTR_ITEM_KEY 24 -#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. - */ -#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 -/* - * extent data is for file data - */ -#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 map tree. These record which blocks - * are used, and how many references there are to each block - */ -#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. Which - * blocks are free etc etc - */ -#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 - -/* - * Persistantly 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). - */ -#if BTRFS_UUID_SIZE != 16 -#error "UUID items require BTRFS_UUID_SIZE == 16!" -#endif -#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 */ -#define BTRFS_CSUM_TYPE_CRC32 0 - -/* - * flags definitions for directory entry item type - * - * Used by: - * struct btrfs_dir_item.type - */ -#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 - -/* - * 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. - */ - -struct btrfs_key { - __u64 objectid; - __u8 type; - __u64 offset; -} __attribute__ ((__packed__)); - -struct btrfs_dev_item { - /* the internal btrfs device id */ - __u64 devid; - - /* size of the device */ - __u64 total_bytes; - - /* bytes used */ - __u64 bytes_used; - - /* optimal io alignment for this device */ - __u32 io_align; - - /* optimal io width for this device */ - __u32 io_width; - - /* minimal io size for this device */ - __u32 sector_size; - - /* type and info about this device */ - __u64 type; - - /* expected generation for this device */ - __u64 generation; - - /* - * starting byte of this partition on the device, - * to allow for stripe alignment in the future - */ - __u64 start_offset; - - /* grouping information for allocation decisions */ - __u32 dev_group; - - /* seek speed 0-100 where 100 is fastest */ - __u8 seek_speed; - - /* 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 { - __u64 devid; - __u64 offset; - __u8 dev_uuid[BTRFS_UUID_SIZE]; -} __attribute__ ((__packed__)); - -struct btrfs_chunk { - /* size of this chunk in bytes */ - __u64 length; - - /* objectid of the root referencing this chunk */ - __u64 owner; - - __u64 stripe_len; - __u64 type; - - /* optimal io alignment for this chunk */ - __u32 io_align; - - /* optimal io width for this chunk */ - __u32 io_width; - - /* minimal io size for this chunk */ - __u32 sector_size; - - /* 2^16 stripes is quite a lot, a second limit is the size of a single - * item in the btree - */ - __u16 num_stripes; - - /* sub stripes only matter for raid10 */ - __u16 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 { - __u64 offset; - __u64 bytes; - __u8 type; -} __attribute__ ((__packed__)); - -struct btrfs_free_space_header { - struct btrfs_key location; - __u64 generation; - __u64 num_entries; - __u64 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) - - -/* - * 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 { - __u64 refs; - __u64 generation; - __u64 flags; -} __attribute__ ((__packed__)); - - -#define BTRFS_EXTENT_FLAG_DATA (1ULL << 0) -#define BTRFS_EXTENT_FLAG_TREE_BLOCK (1ULL << 1) - -/* following flags only apply to tree blocks */ - -/* 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_key key; - __u8 level; -} __attribute__ ((__packed__)); - -struct btrfs_extent_data_ref { - __u64 root; - __u64 objectid; - __u64 offset; - __u32 count; -} __attribute__ ((__packed__)); - -struct btrfs_shared_data_ref { - __u32 count; -} __attribute__ ((__packed__)); - -struct btrfs_extent_inline_ref { - __u8 type; - __u64 offset; -} __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 { - __u64 chunk_tree; - __u64 chunk_objectid; - __u64 chunk_offset; - __u64 length; - __u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; -} __attribute__ ((__packed__)); - -struct btrfs_inode_ref { - __u64 index; - __u16 name_len; - /* name goes here */ -} __attribute__ ((__packed__)); - -struct btrfs_inode_extref { - __u64 parent_objectid; - __u64 index; - __u16 name_len; - __u8 name[0]; - /* name goes here */ -} __attribute__ ((__packed__)); - -struct btrfs_timespec { - __u64 sec; - __u32 nsec; -} __attribute__ ((__packed__)); - -struct btrfs_inode_item { - /* nfs style generation number */ - __u64 generation; - /* transid that last touched this inode */ - __u64 transid; - __u64 size; - __u64 nbytes; - __u64 block_group; - __u32 nlink; - __u32 uid; - __u32 gid; - __u32 mode; - __u64 rdev; - __u64 flags; - - /* modification sequence number for NFS */ - __u64 sequence; - - /* - * a little future expansion, for more than this we can - * just grow the inode item and version it - */ - __u64 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 { - __u64 end; -} __attribute__ ((__packed__)); - -struct btrfs_dir_item { - struct btrfs_key location; - __u64 transid; - __u16 data_len; - __u16 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; - __u64 generation; - __u64 root_dirid; - __u64 bytenr; - __u64 byte_limit; - __u64 bytes_used; - __u64 last_snapshot; - __u64 flags; - __u32 refs; - struct btrfs_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. - */ - __u64 generation_v2; - __u8 uuid[BTRFS_UUID_SIZE]; - __u8 parent_uuid[BTRFS_UUID_SIZE]; - __u8 received_uuid[BTRFS_UUID_SIZE]; - __u64 ctransid; /* updated when an inode changes */ - __u64 otransid; /* trans when created */ - __u64 stransid; /* trans when sent. non-zero for received subvol */ - __u64 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; - __u64 reserved[8]; /* for future */ -} __attribute__ ((__packed__)); - -/* - * this is used for both forward and backward root refs - */ -struct btrfs_root_ref { - __u64 dirid; - __u64 sequence; - __u16 name_len; -} __attribute__ ((__packed__)); - -#define BTRFS_FILE_EXTENT_INLINE 0 -#define BTRFS_FILE_EXTENT_REG 1 -#define BTRFS_FILE_EXTENT_PREALLOC 2 - -enum btrfs_compression_type { - BTRFS_COMPRESS_NONE = 0, - BTRFS_COMPRESS_ZLIB = 1, - BTRFS_COMPRESS_LZO = 2, - BTRFS_COMPRESS_ZSTD = 3, - BTRFS_COMPRESS_TYPES = 3, - BTRFS_COMPRESS_LAST = 4, -}; - -struct btrfs_file_extent_item { - /* - * transaction id that created this extent - */ - __u64 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. - */ - __u64 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; - __u16 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 included - * in these numbers - * - * At this offset in the structure, the inline extent data start. - */ - __u64 disk_bytenr; - __u64 disk_num_bytes; - /* - * the logical offset in file blocks (no csums) - * this extent record is for. 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 - */ - __u64 offset; - /* - * the logical number of file blocks (no csums included). This - * always reflects the size uncompressed and without encoding. - */ - __u64 num_bytes; - -} __attribute__ ((__packed__)); - -struct btrfs_csum_item { - __u8 csum; -} __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_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_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_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) - -/* - * 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) - -#endif /* __BTRFS_BTRFS_TREE_H__ */ diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 65c152a52f..156ce69ed0 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -11,28 +11,16 @@ #include #include -#include "btrfs_tree.h" - -#define BTRFS_MAGIC 0x4D5F53665248425FULL /* ascii _BHRfS_M, no null */ +#include "kernel-shared/btrfs_tree.h" #define BTRFS_MAX_MIRRORS 3 -#define BTRFS_MAX_LEVEL 8 - -#define BTRFS_COMPAT_EXTENT_TREE_V0 - /* * the max metadata block size. This limit is somewhat artificial, * but the memmove costs go through the roof for larger blocks. */ #define BTRFS_MAX_METADATA_BLOCKSIZE 65536 -/* - * 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 @@ -40,8 +28,6 @@ */ #define BTRFS_LINK_MAX 65535U -static const int btrfs_csum_sizes[] = { 4 }; - /* four bytes for CRC32 */ #define BTRFS_EMPTY_DIR_SIZE 0 @@ -61,207 +47,12 @@ static const int btrfs_csum_sizes[] = { 4 }; #define BTRFS_FS_STATE_DEV_REPLACING 3 #define BTRFS_FS_STATE_DUMMY_FS_INFO 4 -#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 - -/* - * 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 */ - __u64 bytenr; /* which block this node is supposed to live in */ - __u64 flags; - - /* allowed to be different from the super from here on down */ - __u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; - __u64 generation; - __u64 owner; - __u32 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 { - __u64 tree_root; - __u64 tree_root_gen; - - __u64 chunk_root; - __u64 chunk_root_gen; - - __u64 extent_root; - __u64 extent_root_gen; - - __u64 fs_root; - __u64 fs_root_gen; - - __u64 dev_root; - __u64 dev_root_gen; - - __u64 csum_root; - __u64 csum_root_gen; - - __u64 total_bytes; - __u64 bytes_used; - __u64 num_devices; - /* future */ - __u64 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__)); - -/* - * the super block basically lists the main trees of the FS - * it currently lacks any block count etc etc - */ -struct btrfs_super_block { - __u8 csum[BTRFS_CSUM_SIZE]; - /* the first 4 fields must match struct btrfs_header */ - __u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */ - __u64 bytenr; /* this block number */ - __u64 flags; - - /* allowed to be different from the btrfs_header from here own down */ - __u64 magic; - __u64 generation; - __u64 root; - __u64 chunk_root; - __u64 log_root; - - /* this will help find the new super based on the log root */ - __u64 log_root_transid; - __u64 total_bytes; - __u64 bytes_used; - __u64 root_dir_objectid; - __u64 num_devices; - __u32 sectorsize; - __u32 nodesize; - __u32 __unused_leafsize; - __u32 stripesize; - __u32 sys_chunk_array_size; - __u64 chunk_root_generation; - __u64 compat_flags; - __u64 compat_ro_flags; - __u64 incompat_flags; - __u16 csum_type; - __u8 root_level; - __u8 chunk_root_level; - __u8 log_root_level; - struct btrfs_dev_item dev_item; - - char label[BTRFS_LABEL_SIZE]; - - __u64 cache_generation; - __u64 uuid_tree_generation; - - /* future expansion */ - __u64 reserved[30]; - __u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE]; - struct btrfs_root_backup super_roots[BTRFS_NUM_BACKUP_ROOTS]; -} __attribute__ ((__packed__)); - -/* - * 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_RAID56 | \ - BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF | \ - BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA | \ - BTRFS_FEATURE_INCOMPAT_NO_HOLES) - -#define BTRFS_FEATURE_INCOMPAT_SAFE_SET \ - (BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF) -#define BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR 0ULL - -/* - * 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_key key; - __u32 offset; - __u32 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_key key; - __u64 blockptr; - __u64 generation; -} __attribute__ ((__packed__)); - -struct btrfs_node { - struct btrfs_header header; - struct btrfs_key_ptr ptrs[]; -} __attribute__ ((__packed__)); - union btrfs_tree_node { struct btrfs_header header; struct btrfs_leaf leaf; struct btrfs_node node; }; -typedef __u8 u8; -typedef __u16 u16; -typedef __u32 u32; -typedef __u64 u64; - struct btrfs_path { union btrfs_tree_node *nodes[BTRFS_MAX_LEVEL]; u32 slots[BTRFS_MAX_LEVEL]; @@ -283,7 +74,8 @@ int btrfs_prev_slot(struct btrfs_path *); int btrfs_next_slot(struct btrfs_path *); static inline struct btrfs_key *btrfs_path_leaf_key(struct btrfs_path *p) { - return &p->nodes[0]->leaf.items[p->slots[0]].key; + /* At tree read time we have converted the endian for btrfs_disk_key */ + return (struct btrfs_key *)&p->nodes[0]->leaf.items[p->slots[0]].key; } static inline struct btrfs_key * diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 991c2f68c3..d88ae67217 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -29,7 +29,7 @@ u64 btrfs_lookup_inode_ref(struct btrfs_root *root, u64 inr, *refp = *ref; if (name) { - if (ref->name_len > BTRFS_NAME_MAX) { + if (ref->name_len > BTRFS_NAME_LEN) { printf("%s: inode name too long: %u\n", __func__, ref->name_len); goto out; @@ -255,7 +255,8 @@ u64 btrfs_lookup_path(struct btrfs_root *root, u64 inr, const char *path, type = item.type; have_inode = 1; - if (btrfs_lookup_inode(root, &item.location, &inode_item, root)) + if (btrfs_lookup_inode(root, (struct btrfs_key *)&item.location, + &inode_item, root)) return -1ULL; if (item.type == BTRFS_FT_SYMLINK && symlink_limit >= 0) { diff --git a/fs/btrfs/kernel-shared/btrfs_tree.h b/fs/btrfs/kernel-shared/btrfs_tree.h new file mode 100644 index 0000000000..6a76d1e456 --- /dev/null +++ b/fs/btrfs/kernel-shared/btrfs_tree.h @@ -0,0 +1,1333 @@ +/* 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__ */ diff --git a/fs/btrfs/root.c b/fs/btrfs/root.c index 127b67fd1c..61155e8918 100644 --- a/fs/btrfs/root.c +++ b/fs/btrfs/root.c @@ -75,7 +75,7 @@ u64 btrfs_lookup_root_ref(u64 subvolid, struct btrfs_root_ref *refp, char *name) *refp = *ref; if (name) { - if (ref->name_len > BTRFS_VOL_NAME_MAX) { + if (ref->name_len > BTRFS_NAME_LEN) { printf("%s: volume name too long: %u\n", __func__, ref->name_len); goto out; diff --git a/fs/btrfs/subvolume.c b/fs/btrfs/subvolume.c index 06e54f3310..dbe92d13cb 100644 --- a/fs/btrfs/subvolume.c +++ b/fs/btrfs/subvolume.c @@ -14,7 +14,7 @@ static int get_subvol_name(u64 subvolid, char *name, int max_len) struct btrfs_inode_ref iref; struct btrfs_root root; u64 dir; - char tmp[max(BTRFS_VOL_NAME_MAX, BTRFS_NAME_MAX)]; + char tmp[BTRFS_NAME_LEN]; char *ptr; ptr = name + max_len - 1;