From d9c9960f8d4bf1ca9b1b491f1f5de5475515dbfc Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 13 Mar 2007 16:47:54 -0400 Subject: Change the super to point to a tree of trees to enable persistent snapshots --- ctree.h | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 107 insertions(+), 16 deletions(-) (limited to 'ctree.h') diff --git a/ctree.h b/ctree.h index 5dfcc908..0968899f 100644 --- a/ctree.h +++ b/ctree.h @@ -4,8 +4,13 @@ #include "list.h" #include "kerncompat.h" +#define BTRFS_MAGIC "_BtRfS_M" #define BTRFS_BLOCKSIZE 1024 +#define BTRFS_ROOT_TREE_OBJECTID 1 +#define BTRFS_EXTENT_TREE_OBJECTID 2 +#define BTRFS_FS_TREE_OBJECTID 3 + /* * the key defines the order in the tree, and so it also defines (optimal) * block layout. objectid corresonds to the inode number. The flags @@ -36,7 +41,7 @@ struct btrfs_key { * every tree block (leaf or node) starts with this header. */ struct btrfs_header { - __le64 fsid[2]; /* FS specific uuid */ + u8 fsid[16]; /* FS specific uuid */ __le64 blocknr; /* which block this node is supposed to live in */ __le64 parentid; /* objectid of the tree root */ __le32 csum; @@ -52,6 +57,14 @@ struct btrfs_header { struct btrfs_buffer; +struct btrfs_root_item { + __le64 blocknr; + __le32 flags; + __le64 block_limit; + __le64 blocks_used; + __le32 refs; +}; + /* * in ram representation of the tree. extent_root is used for all allocations * and for the extent tree extent_root root. current_insert is used @@ -61,6 +74,7 @@ struct btrfs_root { struct btrfs_buffer *node; struct btrfs_buffer *commit_root; struct btrfs_root *extent_root; + struct btrfs_root *tree_root; struct btrfs_key current_insert; struct btrfs_key last_insert; int fp; @@ -69,28 +83,25 @@ struct btrfs_root { struct list_head trans; struct list_head cache; int cache_size; + int ref_cows; + struct btrfs_root_item root_item; + struct btrfs_key root_key; }; -/* - * describes a tree on disk - */ -struct btrfs_root_info { - u64 fsid[2]; /* FS specific uuid */ - u64 blocknr; /* blocknr of this block */ - u64 objectid; /* inode number of this root */ - u64 tree_root; /* the tree root block */ - u32 csum; - u32 ham; - u64 snapuuid[2]; /* root specific uuid */ -} __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 { - struct btrfs_root_info root_info; - struct btrfs_root_info extent_info; + u8 fsid[16]; /* FS specific uuid */ + __le64 blocknr; /* this block number */ + __le32 csum; + __le64 magic; + __le16 blocksize; + __le64 generation; + __le64 root; + __le64 total_blocks; + __le64 blocks_used; } __attribute__ ((__packed__)); /* @@ -317,6 +328,79 @@ static inline int btrfs_is_leaf(struct btrfs_node *n) return (btrfs_header_level(&n->header) == 0); } +static inline u64 btrfs_root_blocknr(struct btrfs_root_item *item) +{ + return le64_to_cpu(item->blocknr); +} + +static inline void btrfs_set_root_blocknr(struct btrfs_root_item *item, u64 val) +{ + item->blocknr = cpu_to_le64(val); +} + +static inline u32 btrfs_root_refs(struct btrfs_root_item *item) +{ + return le32_to_cpu(item->refs); +} + +static inline void btrfs_set_root_refs(struct btrfs_root_item *item, u32 val) +{ + item->refs = cpu_to_le32(val); +} + +static inline u64 btrfs_super_blocknr(struct btrfs_super_block *s) +{ + return le64_to_cpu(s->blocknr); +} + +static inline void btrfs_set_super_blocknr(struct btrfs_super_block *s, u64 val) +{ + s->blocknr = cpu_to_le64(val); +} + +static inline u64 btrfs_super_root(struct btrfs_super_block *s) +{ + return le64_to_cpu(s->root); +} + +static inline void btrfs_set_super_root(struct btrfs_super_block *s, u64 val) +{ + s->root = cpu_to_le64(val); +} + +static inline u64 btrfs_super_total_blocks(struct btrfs_super_block *s) +{ + return le64_to_cpu(s->total_blocks); +} + +static inline void btrfs_set_super_total_blocks(struct btrfs_super_block *s, + u64 val) +{ + s->total_blocks = cpu_to_le64(val); +} + +static inline u64 btrfs_super_blocks_used(struct btrfs_super_block *s) +{ + return le64_to_cpu(s->blocks_used); +} + +static inline void btrfs_set_super_blocks_used(struct btrfs_super_block *s, + u64 val) +{ + s->blocks_used = cpu_to_le64(val); +} + +static inline u16 btrfs_super_blocksize(struct btrfs_super_block *s) +{ + return le16_to_cpu(s->blocksize); +} + +static inline void btrfs_set_super_blocksize(struct btrfs_super_block *s, + u16 val) +{ + s->blocksize = cpu_to_le16(val); +} + struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_root *root); int btrfs_inc_ref(struct btrfs_root *root, struct btrfs_buffer *buf); int btrfs_free_extent(struct btrfs_root *root, u64 blocknr, u64 num_blocks); @@ -331,4 +415,11 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path); int btrfs_leaf_free_space(struct btrfs_leaf *leaf); int btrfs_drop_snapshot(struct btrfs_root *root, struct btrfs_buffer *snap); int btrfs_finish_extent_commit(struct btrfs_root *root); +int btrfs_del_root(struct btrfs_root *root, struct btrfs_key *key); +int btrfs_insert_root(struct btrfs_root *root, struct btrfs_key *key, + struct btrfs_root_item *item); +int btrfs_update_root(struct btrfs_root *root, struct btrfs_key *key, + struct btrfs_root_item *item); +int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, + struct btrfs_root_item *item, struct btrfs_key *key); #endif -- cgit v1.2.3