linux/fs/btrfs/ctree.h

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#ifndef __CTREE__
#define __CTREE__
#define CTREE_BLOCKSIZE 4096
struct key {
u64 objectid;
u32 flags;
u64 offset;
} __attribute__ ((__packed__));
struct header {
u64 fsid[2]; /* FS specific uuid */
u64 blocknr;
u64 parentid;
u32 csum;
u32 ham;
u16 nritems;
u16 flags;
} __attribute__ ((__packed__));
#define NODEPTRS_PER_BLOCK ((CTREE_BLOCKSIZE - sizeof(struct header)) / \
(sizeof(struct key) + sizeof(u64)))
#define LEVEL_BITS 3
#define MAX_LEVEL (1 << LEVEL_BITS)
#define node_level(f) ((f) & (MAX_LEVEL-1))
#define is_leaf(f) (node_level(f) == 0)
struct tree_buffer;
struct ctree_root {
struct tree_buffer *node;
int fp;
struct radix_tree_root cache_radix;
};
struct item {
struct key key;
u16 offset;
u16 size;
} __attribute__ ((__packed__));
#define LEAF_DATA_SIZE (CTREE_BLOCKSIZE - sizeof(struct header))
struct leaf {
struct header header;
union {
struct item items[LEAF_DATA_SIZE/sizeof(struct item)];
u8 data[CTREE_BLOCKSIZE-sizeof(struct header)];
};
} __attribute__ ((__packed__));
struct node {
struct header header;
struct key keys[NODEPTRS_PER_BLOCK];
u64 blockptrs[NODEPTRS_PER_BLOCK];
} __attribute__ ((__packed__));
struct ctree_path {
struct tree_buffer *nodes[MAX_LEVEL];
int slots[MAX_LEVEL];
};
#endif