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Diffstat (limited to 'fs/btrfs/ctree.h')
| -rw-r--r-- | fs/btrfs/ctree.h | 2043 |
1 files changed, 2043 insertions, 0 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h new file mode 100644 index 00000000000..0f2a9b584fb --- /dev/null +++ b/fs/btrfs/ctree.h @@ -0,0 +1,2043 @@ +/* + * Copyright (C) 2007 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#ifndef __BTRFS_CTREE__ +#define __BTRFS_CTREE__ + +#include <linux/version.h> +#include <linux/mm.h> +#include <linux/highmem.h> +#include <linux/fs.h> +#include <linux/completion.h> +#include <linux/backing-dev.h> +#include <linux/wait.h> +#include <asm/kmap_types.h> +#include "extent_io.h" +#include "extent_map.h" +#include "async-thread.h" + +struct btrfs_trans_handle; +struct btrfs_transaction; +extern struct kmem_cache *btrfs_trans_handle_cachep; +extern struct kmem_cache *btrfs_transaction_cachep; +extern struct kmem_cache *btrfs_bit_radix_cachep; +extern struct kmem_cache *btrfs_path_cachep; +struct btrfs_ordered_sum; + +#define BTRFS_MAGIC "_BFRfS_M" + +#define BTRFS_ACL_NOT_CACHED ((void *)-1) + +#ifdef CONFIG_LOCKDEP +# define BTRFS_MAX_LEVEL 7 +#else +# define BTRFS_MAX_LEVEL 8 +#endif + +/* 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 + +/* 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 + +/* 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 + +/* + * we can actually store much bigger names, but lets not confuse the rest + * of linux + */ +#define BTRFS_NAME_LEN 255 + +/* 32 bytes in various csum fields */ +#define BTRFS_CSUM_SIZE 32 +/* four bytes for CRC32 */ +#define BTRFS_CRC32_SIZE 4 +#define BTRFS_EMPTY_DIR_SIZE 0 + +#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 corresonds to the inode number. The flags + * tells us things about the object, and is a kind of stream selector. + * so for a given inode, keys with flags of 1 might refer to the inode + * data, flags of 2 may point to file data in the btree and flags == 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 { + __le64 objectid; + u8 type; + __le64 offset; +} __attribute__ ((__packed__)); + +struct btrfs_key { + u64 objectid; + u8 type; + u64 offset; +} __attribute__ ((__packed__)); + +struct btrfs_mapping_tree { + struct extent_map_tree map_tree; +}; + +#define BTRFS_UUID_SIZE 16 +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; + + /* grouping information for allocation decisions */ + __le32 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 { + __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__)); + +static inline unsigned long btrfs_chunk_item_size(int num_stripes) +{ + BUG_ON(num_stripes == 0); + return sizeof(struct btrfs_chunk) + + sizeof(struct btrfs_stripe) * (num_stripes - 1); +} + +#define BTRFS_FSID_SIZE 16 +#define BTRFS_HEADER_FLAG_WRITTEN (1 << 0) + +/* + * 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__)); + +#define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \ + sizeof(struct btrfs_header)) / \ + sizeof(struct btrfs_key_ptr)) +#define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header)) +#define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize)) +#define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \ + sizeof(struct btrfs_item) - \ + sizeof(struct btrfs_file_extent_item)) + +#define BTRFS_SUPER_FLAG_SEEDING (1ULL << 32) + +/* + * 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 + * 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 */ + __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; + __le64 total_bytes; + __le64 bytes_used; + __le64 root_dir_objectid; + __le64 num_devices; + __le32 sectorsize; + __le32 nodesize; + __le32 leafsize; + __le32 stripesize; + __le32 sys_chunk_array_size; + __le64 chunk_root_generation; + u8 root_level; + u8 chunk_root_level; + u8 log_root_level; + struct btrfs_dev_item dev_item; + char label[BTRFS_LABEL_SIZE]; + u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE]; +} __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__)); + +/* + * btrfs_paths remember the path taken from the root down to the leaf. + * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point + * to any other levels that are present. + * + * The slots array records the index of the item or block pointer + * used while walking the tree. + */ +struct btrfs_path { + struct extent_buffer *nodes[BTRFS_MAX_LEVEL]; + int slots[BTRFS_MAX_LEVEL]; + /* if there is real range locking, this locks field will change */ + int locks[BTRFS_MAX_LEVEL]; + int reada; + /* keep some upper locks as we walk down */ + int keep_locks; + int skip_locking; + int lowest_level; +}; + +/* + * 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 { + __le32 refs; +} __attribute__ ((__packed__)); + +struct btrfs_extent_ref { + __le64 root; + __le64 generation; + __le64 objectid; + __le32 num_refs; +} __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 { + __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_timespec { + __le64 sec; + __le32 nsec; +} __attribute__ ((__packed__)); + +typedef enum { + BTRFS_COMPRESS_NONE = 0, + BTRFS_COMPRESS_ZLIB = 1, + BTRFS_COMPRESS_LAST = 2, +} btrfs_compression_type; + +/* we don't understand any encryption methods right now */ +typedef enum { + BTRFS_ENCRYPTION_NONE = 0, + BTRFS_ENCRYPTION_LAST = 1, +} btrfs_encryption_type; + +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; + __le16 flags; + __le16 compat_flags; + + 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__)); + +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; + __le32 flags; + __le32 refs; + struct btrfs_disk_key drop_progress; + u8 drop_level; + u8 level; +} __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__)); + +#define BTRFS_FILE_EXTENT_INLINE 0 +#define BTRFS_FILE_EXTENT_REG 1 +#define BTRFS_FILE_EXTENT_PREALLOC 2 + +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 included + * in these numbers + */ + __le64 disk_bytenr; + __le64 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 + */ + __le64 offset; + /* + * the logical number of file blocks (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__)); + +/* different types of block groups (and chunks) */ +#define BTRFS_BLOCK_GROUP_DATA (1 << 0) +#define BTRFS_BLOCK_GROUP_SYSTEM (1 << 1) +#define BTRFS_BLOCK_GROUP_METADATA (1 << 2) +#define BTRFS_BLOCK_GROUP_RAID0 (1 << 3) +#define BTRFS_BLOCK_GROUP_RAID1 (1 << 4) +#define BTRFS_BLOCK_GROUP_DUP (1 << 5) +#define BTRFS_BLOCK_GROUP_RAID10 (1 << 6) + +struct btrfs_block_group_item { + __le64 used; + __le64 chunk_objectid; + __le64 flags; +} __attribute__ ((__packed__)); + +struct btrfs_space_info { + u64 flags; + u64 total_bytes; + u64 bytes_used; + u64 bytes_pinned; + u64 bytes_reserved; + u64 bytes_readonly; + int full; + int force_alloc; + struct list_head list; + + /* for block groups in our same type */ + struct list_head block_groups; + spinlock_t lock; + struct rw_semaphore groups_sem; +}; + +struct btrfs_free_space { + struct rb_node bytes_index; + struct rb_node offset_index; + u64 offset; + u64 bytes; +}; + +struct btrfs_block_group_cache { + struct btrfs_key key; + struct btrfs_block_group_item item; + spinlock_t lock; + struct mutex alloc_mutex; + u64 pinned; + u64 reserved; + u64 flags; + int cached; + int ro; + int dirty; + + struct btrfs_space_info *space_info; + + /* free space cache stuff */ + struct rb_root free_space_bytes; + struct rb_root free_space_offset; + + /* block group cache stuff */ + struct rb_node cache_node; + + /* for block groups in the same raid type */ + struct list_head list; +}; + +struct btrfs_leaf_ref_tree { + struct rb_root root; + struct list_head list; + spinlock_t lock; +}; + +struct btrfs_device; +struct btrfs_fs_devices; +struct btrfs_fs_info { + u8 fsid[BTRFS_FSID_SIZE]; + u8 chunk_tree_uuid[BTRFS_UUID_SIZE]; + struct btrfs_root *extent_root; + struct btrfs_root *tree_root; + struct btrfs_root *chunk_root; + struct btrfs_root *dev_root; + struct btrfs_root *fs_root; + + /* the log root tree is a directory of all the other log roots */ + struct btrfs_root *log_root_tree; + struct radix_tree_root fs_roots_radix; + + /* block group cache stuff */ + spinlock_t block_group_cache_lock; + struct rb_root block_group_cache_tree; + + struct extent_io_tree pinned_extents; + struct extent_io_tree pending_del; + struct extent_io_tree extent_ins; + + /* logical->physical extent mapping */ + struct btrfs_mapping_tree mapping_tree; + + u64 generation; + u64 last_trans_committed; + u64 last_trans_new_blockgroup; + u64 open_ioctl_trans; + unsigned long mount_opt; + u64 max_extent; + u64 max_inline; + u64 alloc_start; + struct btrfs_transaction *running_transaction; + wait_queue_head_t transaction_throttle; + wait_queue_head_t transaction_wait; + + wait_queue_head_t async_submit_wait; + wait_queue_head_t tree_log_wait; + + struct btrfs_super_block super_copy; + struct btrfs_super_block super_for_commit; + struct block_device *__bdev; + struct super_block *sb; + struct inode *btree_inode; + struct backing_dev_info bdi; + spinlock_t hash_lock; + struct mutex trans_mutex; + struct mutex tree_log_mutex; + struct mutex transaction_kthread_mutex; + struct mutex cleaner_mutex; + struct mutex extent_ins_mutex; + struct mutex pinned_mutex; + struct mutex chunk_mutex; + struct mutex drop_mutex; + struct mutex volume_mutex; + struct mutex tree_reloc_mutex; + struct list_head trans_list; + struct list_head hashers; + struct list_head dead_roots; + + atomic_t nr_async_submits; + atomic_t async_submit_draining; + atomic_t nr_async_bios; + atomic_t async_delalloc_pages; + atomic_t tree_log_writers; + atomic_t tree_log_commit; + unsigned long tree_log_batch; + u64 tree_log_transid; + + /* + * this is used by the balancing code to wait for all the pending + * ordered extents + */ + spinlock_t ordered_extent_lock; + struct list_head ordered_extents; + struct list_head delalloc_inodes; + + /* + * there is a pool of worker threads for checksumming during writes + * and a pool for checksumming after reads. This is because readers + * can run with FS locks held, and the writers may be waiting for + * those locks. We don't want ordering in the pending list to cause + * deadlocks, and so the two are serviced separately. + * + * A third pool does submit_bio to avoid deadlocking with the other + * two + */ + struct btrfs_workers workers; + struct btrfs_workers delalloc_workers; + struct btrfs_workers endio_workers; + struct btrfs_workers endio_write_workers; + struct btrfs_workers submit_workers; + /* + * fixup workers take dirty pages that didn't properly go through + * the cow mechanism and make them safe to write. It happens + * for the sys_munmap function call path + */ + struct btrfs_workers fixup_workers; + struct task_struct *transaction_kthread; + struct task_struct *cleaner_kthread; + int thread_pool_size; + + /* tree relocation relocated fields */ + struct list_head dead_reloc_roots; + struct btrfs_leaf_ref_tree reloc_ref_tree; + struct btrfs_leaf_ref_tree shared_ref_tree; + + struct kobject super_kobj; + struct completion kobj_unregister; + int do_barriers; + int closing; + int log_root_recovering; + atomic_t throttles; + atomic_t throttle_gen; + + u64 total_pinned; + struct list_head dirty_cowonly_roots; + + struct btrfs_fs_devices *fs_devices; + struct list_head space_info; + spinlock_t delalloc_lock; + spinlock_t new_trans_lock; + u64 delalloc_bytes; + u64 last_alloc; + u64 last_data_alloc; + + spinlock_t ref_cache_lock; + u64 total_ref_cache_size; + + u64 avail_data_alloc_bits; + u64 avail_metadata_alloc_bits; + u64 avail_system_alloc_bits; + u64 data_alloc_profile; + u64 metadata_alloc_profile; + u64 system_alloc_profile; + + void *bdev_holder; +}; + +/* + * in ram representation of the tree. extent_root is used for all allocations + * and for the extent tree extent_root root. + */ +struct btrfs_dirty_root; +struct btrfs_root { + struct extent_buffer *node; + + /* the node lock is held while changing the node pointer */ + spinlock_t node_lock; + + struct extent_buffer *commit_root; + struct btrfs_leaf_ref_tree *ref_tree; + struct btrfs_leaf_ref_tree ref_tree_struct; + struct btrfs_dirty_root *dirty_root; + struct btrfs_root *log_root; + struct btrfs_root *reloc_root; + + struct btrfs_root_item root_item; + struct btrfs_key root_key; + struct btrfs_fs_info *fs_info; + struct extent_io_tree dirty_log_pages; + + struct kobject root_kobj; + struct completion kobj_unregister; + struct mutex objectid_mutex; + struct mutex log_mutex; + + u64 objectid; + u64 last_trans; + + /* data allocations are done in sectorsize units */ + u32 sectorsize; + + /* node allocations are done in nodesize units */ + u32 nodesize; + + /* leaf allocations are done in leafsize units */ + u32 leafsize; + + u32 stripesize; + + u32 type; + u64 highest_inode; + u64 last_inode_alloc; + int ref_cows; + int track_dirty; + u64 defrag_trans_start; + struct btrfs_key defrag_progress; + struct btrfs_key defrag_max; + int defrag_running; + int defrag_level; + char *name; + int in_sysfs; + + /* the dirty list is only used by non-reference counted roots */ + struct list_head dirty_list; + + spinlock_t list_lock; + struct list_head dead_list; + struct list_head orphan_list; + + /* + * right now this just gets used so that a root has its own devid + * for stat. It may be used for more later + */ + struct super_block anon_super; +}; + +/* + + * 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_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 +/* + * csum items have the checksums for data in the extents + */ +#define BTRFS_CSUM_ITEM_KEY 120 + + +/* reserve 21-31 for other file/dir stuff */ + +/* + * root items point to tree roots. There 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 +#define BTRFS_EXTENT_REF_KEY 180 + +/* + * block groups give us hints into the extent allocation trees. Which + * blocks are free etc etc + */ +#define BTRFS_BLOCK_GROUP_ITEM_KEY 192 + +#define BTRFS_DEV_EXTENT_KEY 204 +#define BTRFS_DEV_ITEM_KEY 216 +#define BTRFS_CHUNK_ITEM_KEY 228 + +/* + * string items are for debugging. They just store a short string of + * data in the FS + */ +#define BTRFS_STRING_ITEM_KEY 253 + +#define BTRFS_MOUNT_NODATASUM (1 << 0) +#define BTRFS_MOUNT_NODATACOW (1 << 1) +#define BTRFS_MOUNT_NOBARRIER (1 << 2) +#define BTRFS_MOUNT_SSD (1 << 3) +#define BTRFS_MOUNT_DEGRADED (1 << 4) +#define BTRFS_MOUNT_COMPRESS (1 << 5) + +#define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt) +#define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt) +#define btrfs_test_opt(root, opt) ((root)->fs_info->mount_opt & \ + BTRFS_MOUNT_##opt) +/* + * 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_clear_flag(inode, flag) (BTRFS_I(inode)->flags &= \ + ~BTRFS_INODE_##flag) +#define btrfs_set_flag(inode, flag) (BTRFS_I(inode)->flags |= \ + BTRFS_INODE_##flag) +#define btrfs_test_flag(inode, flag) (BTRFS_I(inode)->flags & \ + BTRFS_INODE_##flag) +/* some macros to generate set/get funcs for the struct fields. This + * assumes there is a lefoo_to_cpu for every type, so lets make a simple + * one for u8: + */ +#define le8_to_cpu(v) (v) +#define cpu_to_le8(v) (v) +#define __le8 u8 + +#define read_eb_member(eb, ptr, type, member, result) ( \ + read_extent_buffer(eb, (char *)(result), \ + ((unsigned long)(ptr)) + \ + offsetof(type, member), \ + sizeof(((type *)0)->member))) + +#define write_eb_member(eb, ptr, type, member, result) ( \ + write_extent_buffer(eb, (char *)(result), \ + ((unsigned long)(ptr)) + \ + offsetof(type, member), \ + sizeof(((type *)0)->member))) + +#ifndef BTRFS_SETGET_FUNCS +#define BTRFS_SETGET_FUNCS(name, type, member, bits) \ +u##bits btrfs_##name(struct extent_buffer *eb, type *s); \ +void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val); +#endif + +#define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits) \ +static inline u##bits btrfs_##name(struct extent_buffer *eb) \ +{ \ + type *p = kmap_atomic(eb->first_page, KM_USER0); \ + u##bits res = le##bits##_to_cpu(p->member); \ + kunmap_atomic(p, KM_USER0); \ + return res; \ +} \ +static inline void btrfs_set_##name(struct extent_buffer *eb, \ + u##bits val) \ +{ \ + type *p = kmap_atomic(eb->first_page, KM_USER0); \ + p->member = cpu_to_le##bits(val); \ + kunmap_atomic(p, KM_USER0); \ +} + +#define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits) \ +static inline u##bits btrfs_##name(type *s) \ +{ \ + return le##bits##_to_cpu(s->member); \ +} \ +static inline void btrfs_set_##name(type *s, u##bits val) \ +{ \ + s->member = cpu_to_le##bits(val); \ +} + +BTRFS_SETGET_FUNCS(device_type, struct btrfs_dev_item, type, 64); +BTRFS_SETGET_FUNCS(device_total_bytes, struct btrfs_dev_item, total_bytes, 64); +BTRFS_SETGET_FUNCS(device_bytes_used, struct btrfs_dev_item, bytes_used, 64); +BTRFS_SETGET_FUNCS(device_io_align, struct btrfs_dev_item, io_align, 32); +BTRFS_SETGET_FUNCS(device_io_width, struct btrfs_dev_item, io_width, 32); +BTRFS_SETGET_FUNCS(device_sector_size, struct btrfs_dev_item, sector_size, 32); +BTRFS_SETGET_FUNCS(device_id, struct btrfs_dev_item, devid, 64); +BTRFS_SETGET_FUNCS(device_group, struct btrfs_dev_item, dev_group, 32); +BTRFS_SETGET_FUNCS(device_seek_speed, struct btrfs_dev_item, seek_speed, 8); +BTRFS_SETGET_FUNCS(device_bandwidth, struct btrfs_dev_item, bandwidth, 8); +BTRFS_SETGET_FUNCS(device_generation, struct btrfs_dev_item, generation, 64); + +BTRFS_SETGET_STACK_FUNCS(stack_device_type, struct btrfs_dev_item, type, 64); +BTRFS_SETGET_STACK_FUNCS(stack_device_total_bytes, struct btrfs_dev_item, + total_bytes, 64); +BTRFS_SETGET_STACK_FUNCS(stack_device_bytes_used, struct btrfs_dev_item, + bytes_used, 64); +BTRFS_SETGET_STACK_FUNCS(stack_device_io_align, struct btrfs_dev_item, + io_align, 32); +BTRFS_SETGET_STACK_FUNCS(stack_device_io_width, struct btrfs_dev_item, + io_width, 32); +BTRFS_SETGET_STACK_FUNCS(stack_device_sector_size, struct btrfs_dev_item, + sector_size, 32); +BTRFS_SETGET_STACK_FUNCS(stack_device_id, struct btrfs_dev_item, devid, 64); +BTRFS_SETGET_STACK_FUNCS(stack_device_group, struct btrfs_dev_item, + dev_group, 32); +BTRFS_SETGET_STACK_FUNCS(stack_device_seek_speed, struct btrfs_dev_item, + seek_speed, 8); +BTRFS_SETGET_STACK_FUNCS(stack_device_bandwidth, struct btrfs_dev_item, + bandwidth, 8); +BTRFS_SETGET_STACK_FUNCS(stack_device_generation, struct btrfs_dev_item, + generation, 64); + +static inline char *btrfs_device_uuid(struct btrfs_dev_item *d) +{ + return (char *)d + offsetof(struct btrfs_dev_item, uuid); +} + +static inline char *btrfs_device_fsid(struct btrfs_dev_item *d) +{ + return (char *)d + offsetof(struct btrfs_dev_item, fsid); +} + +BTRFS_SETGET_FUNCS(chunk_length, struct btrfs_chunk, length, 64); +BTRFS_SETGET_FUNCS(chunk_owner, struct btrfs_chunk, owner, 64); +BTRFS_SETGET_FUNCS(chunk_stripe_len, struct btrfs_chunk, stripe_len, 64); +BTRFS_SETGET_FUNCS(chunk_io_align, struct btrfs_chunk, io_align, 32); +BTRFS_SETGET_FUNCS(chunk_io_width, struct btrfs_chunk, io_width, 32); +BTRFS_SETGET_FUNCS(chunk_sector_size, struct btrfs_chunk, sector_size, 32); +BTRFS_SETGET_FUNCS(chunk_type, struct btrfs_chunk, type, 64); +BTRFS_SETGET_FUNCS(chunk_num_stripes, struct btrfs_chunk, num_stripes, 16); +BTRFS_SETGET_FUNCS(chunk_sub_stripes, struct btrfs_chunk, sub_stripes, 16); +BTRFS_SETGET_FUNCS(stripe_devid, struct btrfs_stripe, devid, 64); +BTRFS_SETGET_FUNCS(stripe_offset, struct btrfs_stripe, offset, 64); + +static inline char *btrfs_stripe_dev_uuid(struct btrfs_stripe *s) +{ + return (char *)s + offsetof(struct btrfs_stripe, dev_uuid); +} + +BTRFS_SETGET_STACK_FUNCS(stack_chunk_length, struct btrfs_chunk, length, 64); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_owner, struct btrfs_chunk, owner, 64); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_stripe_len, struct btrfs_chunk, + stripe_len, 64); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_io_align, struct btrfs_chunk, + io_align, 32); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_io_width, struct btrfs_chunk, + io_width, 32); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_sector_size, struct btrfs_chunk, + sector_size, 32); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_type, struct btrfs_chunk, type, 64); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_num_stripes, struct btrfs_chunk, + num_stripes, 16); +BTRFS_SETGET_STACK_FUNCS(stack_chunk_sub_stripes, struct btrfs_chunk, + sub_stripes, 16); +BTRFS_SETGET_STACK_FUNCS(stack_stripe_devid, struct btrfs_stripe, devid, 64); +BTRFS_SETGET_STACK_FUNCS(stack_stripe_offset, struct btrfs_stripe, offset, 64); + +static inline struct btrfs_stripe *btrfs_stripe_nr(struct btrfs_chunk *c, + int nr) +{ + unsigned long offset = (unsigned long)c; + offset += offsetof(struct btrfs_chunk, stripe); + offset += nr * sizeof(struct btrfs_stripe); + return (struct btrfs_stripe *)offset; +} + +static inline char *btrfs_stripe_dev_uuid_nr(struct btrfs_chunk *c, int nr) +{ + return btrfs_stripe_dev_uuid(btrfs_stripe_nr(c, nr)); +} + +static inline u64 btrfs_stripe_offset_nr(struct extent_buffer *eb, + struct btrfs_chunk *c, int nr) +{ + return btrfs_stripe_offset(eb, btrfs_stripe_nr(c, nr)); +} + +static inline void btrfs_set_stripe_offset_nr(struct extent_buffer *eb, + struct btrfs_chunk *c, int nr, + u64 val) +{ + btrfs_set_stripe_offset(eb, btrfs_stripe_nr(c, nr), val); +} + +static inline u64 btrfs_stripe_devid_nr(struct extent_buffer *eb, + struct btrfs_chunk *c, int nr) +{ + return btrfs_stripe_devid(eb, btrfs_stripe_nr(c, nr)); +} + +static inline void btrfs_set_stripe_devid_nr(struct extent_buffer *eb, + struct btrfs_chunk *c, int nr, + u64 val) +{ + btrfs_set_stripe_devid(eb, btrfs_stripe_nr(c, nr), val); +} + +/* struct btrfs_block_group_item */ +BTRFS_SETGET_STACK_FUNCS(block_group_used, struct btrfs_block_group_item, + used, 64); +BTRFS_SETGET_FUNCS(disk_block_group_used, struct btrfs_block_group_item, + used, 64); +BTRFS_SETGET_STACK_FUNCS(block_group_chunk_objectid, + struct btrfs_block_group_item, chunk_objectid, 64); + +BTRFS_SETGET_FUNCS(disk_block_group_chunk_objectid, + struct btrfs_block_group_item, chunk_objectid, 64); +BTRFS_SETGET_FUNCS(disk_block_group_flags, + struct btrfs_block_group_item, flags, 64); +BTRFS_SETGET_STACK_FUNCS(block_group_flags, + struct btrfs_block_group_item, flags, 64); + +/* struct btrfs_inode_ref */ +BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16); +BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64); + +/* struct btrfs_inode_item */ +BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64); +BTRFS_SETGET_FUNCS(inode_transid, struct btrfs_inode_item, transid, 64); +BTRFS_SETGET_FUNCS(inode_size, struct btrfs_inode_item, size, 64); +BTRFS_SETGET_FUNCS(inode_nbytes, struct btrfs_inode_item, nbytes, 64); +BTRFS_SETGET_FUNCS(inode_block_group, struct btrfs_inode_item, block_group, 64); +BTRFS_SETGET_FUNCS(inode_nlink, struct btrfs_inode_item, nlink, 32); +BTRFS_SETGET_FUNCS(inode_uid, struct btrfs_inode_item, uid, 32); +BTRFS_SETGET_FUNCS(inode_gid, struct btrfs_inode_item, gid, 32); +BTRFS_SETGET_FUNCS(inode_mode, struct btrfs_inode_item, mode, 32); +BTRFS_SETGET_FUNCS(inode_rdev, struct btrfs_inode_item, rdev, 64); +BTRFS_SETGET_FUNCS(inode_flags, struct btrfs_inode_item, flags, 16); +BTRFS_SETGET_FUNCS(inode_compat_flags, struct btrfs_inode_item, + compat_flags, 16); + +static inline struct btrfs_timespec * +btrfs_inode_atime(struct btrfs_inode_item *inode_item) +{ + unsigned long ptr = (unsigned long)inode_item; + ptr += offsetof(struct btrfs_inode_item, atime); + return (struct btrfs_timespec *)ptr; +} + +static inline struct btrfs_timespec * +btrfs_inode_mtime(struct btrfs_inode_item *inode_item) +{ + unsigned long ptr = (unsigned long)inode_item; + ptr += offsetof(struct btrfs_inode_item, mtime); + return (struct btrfs_timespec *)ptr; +} + +static inline struct btrfs_timespec * +btrfs_inode_ctime(struct btrfs_inode_item *inode_item) +{ + unsigned long ptr = (unsigned long)inode_item; + ptr += offsetof(struct btrfs_inode_item, ctime); + return (struct btrfs_timespec *)ptr; +} + +static inline struct btrfs_timespec * +btrfs_inode_otime(struct btrfs_inode_item *inode_item) +{ + unsigned long ptr = (unsigned long)inode_item; + ptr += offsetof(struct btrfs_inode_item, otime); + return (struct btrfs_timespec *)ptr; +} + +BTRFS_SETGET_FUNCS(timespec_sec, struct btrfs_timespec, sec, 64); +BTRFS_SETGET_FUNCS(timespec_nsec, struct btrfs_timespec, nsec, 32); + +/* struct btrfs_dev_extent */ +BTRFS_SETGET_ |