520 lines
13 KiB
C
520 lines
13 KiB
C
#ifndef __BTRFS__
|
|
#define __BTRFS__
|
|
|
|
#include "list.h"
|
|
#include "kerncompat.h"
|
|
|
|
#define BTRFS_MAGIC "_BtRfS_M"
|
|
|
|
#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
|
|
* 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;
|
|
__le64 offset;
|
|
__le32 flags;
|
|
} __attribute__ ((__packed__));
|
|
|
|
struct btrfs_key {
|
|
u64 objectid;
|
|
u64 offset;
|
|
u32 flags;
|
|
} __attribute__ ((__packed__));
|
|
|
|
/*
|
|
* every tree block (leaf or node) starts with this header.
|
|
*/
|
|
struct btrfs_header {
|
|
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;
|
|
__le32 ham;
|
|
__le16 nritems;
|
|
__le16 flags;
|
|
/* generation flags to be added */
|
|
} __attribute__ ((__packed__));
|
|
|
|
#define BTRFS_MAX_LEVEL 8
|
|
#define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->blocksize - \
|
|
sizeof(struct btrfs_header)) / \
|
|
(sizeof(struct btrfs_disk_key) + sizeof(u64)))
|
|
#define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
|
|
#define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->blocksize))
|
|
|
|
struct btrfs_buffer;
|
|
/*
|
|
* the super block basically lists the main trees of the FS
|
|
* it currently lacks any block count etc etc
|
|
*/
|
|
struct btrfs_super_block {
|
|
u8 fsid[16]; /* FS specific uuid */
|
|
__le64 blocknr; /* this block number */
|
|
__le32 csum;
|
|
__le64 magic;
|
|
__le32 blocksize;
|
|
__le64 generation;
|
|
__le64 root;
|
|
__le64 total_blocks;
|
|
__le64 blocks_used;
|
|
} __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;
|
|
__le16 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;
|
|
} __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 btrfs_buffer *nodes[BTRFS_MAX_LEVEL];
|
|
int slots[BTRFS_MAX_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;
|
|
__le64 owner;
|
|
} __attribute__ ((__packed__));
|
|
|
|
struct btrfs_dir_item {
|
|
__le64 objectid;
|
|
__le16 flags;
|
|
u8 type;
|
|
} __attribute__ ((__packed__));
|
|
|
|
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
|
|
* only for the extent tree.
|
|
*/
|
|
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;
|
|
struct radix_tree_root cache_radix;
|
|
struct radix_tree_root pinned_radix;
|
|
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;
|
|
u32 blocksize;
|
|
};
|
|
|
|
|
|
/* the lower bits in the key flags defines the item type */
|
|
#define BTRFS_KEY_TYPE_MAX 256
|
|
#define BTRFS_KEY_TYPE_MASK (BTRFS_KEY_TYPE_MAX - 1)
|
|
#define BTRFS_INODE_ITEM_KEY 1
|
|
#define BTRFS_DIR_ITEM_KEY 2
|
|
#define BTRFS_ROOT_ITEM_KEY 3
|
|
#define BTRFS_EXTENT_ITEM_KEY 4
|
|
#define BTRFS_STRING_ITEM_KEY 5
|
|
|
|
static inline u64 btrfs_extent_owner(struct btrfs_extent_item *ei)
|
|
{
|
|
return le64_to_cpu(ei->owner);
|
|
}
|
|
|
|
static inline void btrfs_set_extent_owner(struct btrfs_extent_item *ei, u64 val)
|
|
{
|
|
ei->owner = cpu_to_le64(val);
|
|
}
|
|
|
|
static inline u32 btrfs_extent_refs(struct btrfs_extent_item *ei)
|
|
{
|
|
return le32_to_cpu(ei->refs);
|
|
}
|
|
|
|
static inline void btrfs_set_extent_refs(struct btrfs_extent_item *ei, u32 val)
|
|
{
|
|
ei->refs = cpu_to_le32(val);
|
|
}
|
|
|
|
static inline u64 btrfs_node_blockptr(struct btrfs_node *n, int nr)
|
|
{
|
|
return le64_to_cpu(n->ptrs[nr].blockptr);
|
|
}
|
|
|
|
static inline void btrfs_set_node_blockptr(struct btrfs_node *n, int nr,
|
|
u64 val)
|
|
{
|
|
n->ptrs[nr].blockptr = cpu_to_le64(val);
|
|
}
|
|
|
|
static inline u32 btrfs_item_offset(struct btrfs_item *item)
|
|
{
|
|
return le32_to_cpu(item->offset);
|
|
}
|
|
|
|
static inline void btrfs_set_item_offset(struct btrfs_item *item, u32 val)
|
|
{
|
|
item->offset = cpu_to_le32(val);
|
|
}
|
|
|
|
static inline u32 btrfs_item_end(struct btrfs_item *item)
|
|
{
|
|
return le32_to_cpu(item->offset) + le16_to_cpu(item->size);
|
|
}
|
|
|
|
static inline u16 btrfs_item_size(struct btrfs_item *item)
|
|
{
|
|
return le16_to_cpu(item->size);
|
|
}
|
|
|
|
static inline void btrfs_set_item_size(struct btrfs_item *item, u16 val)
|
|
{
|
|
item->size = cpu_to_le16(val);
|
|
}
|
|
|
|
static inline u64 btrfs_dir_objectid(struct btrfs_dir_item *d)
|
|
{
|
|
return le64_to_cpu(d->objectid);
|
|
}
|
|
|
|
static inline void btrfs_set_dir_objectid(struct btrfs_dir_item *d, u64 val)
|
|
{
|
|
d->objectid = cpu_to_le64(val);
|
|
}
|
|
|
|
static inline u16 btrfs_dir_flags(struct btrfs_dir_item *d)
|
|
{
|
|
return le16_to_cpu(d->flags);
|
|
}
|
|
|
|
static inline void btrfs_set_dir_flags(struct btrfs_dir_item *d, u16 val)
|
|
{
|
|
d->flags = cpu_to_le16(val);
|
|
}
|
|
|
|
static inline u8 btrfs_dir_type(struct btrfs_dir_item *d)
|
|
{
|
|
return d->type;
|
|
}
|
|
|
|
static inline void btrfs_set_dir_type(struct btrfs_dir_item *d, u8 val)
|
|
{
|
|
d->type = val;
|
|
}
|
|
|
|
static inline u32 btrfs_dir_name_len(struct btrfs_item *i)
|
|
{
|
|
return btrfs_item_size(i) - sizeof(struct btrfs_dir_item);
|
|
}
|
|
|
|
static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
|
|
struct btrfs_disk_key *disk)
|
|
{
|
|
cpu->offset = le64_to_cpu(disk->offset);
|
|
cpu->flags = le32_to_cpu(disk->flags);
|
|
cpu->objectid = le64_to_cpu(disk->objectid);
|
|
}
|
|
|
|
static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
|
|
struct btrfs_key *cpu)
|
|
{
|
|
disk->offset = cpu_to_le64(cpu->offset);
|
|
disk->flags = cpu_to_le32(cpu->flags);
|
|
disk->objectid = cpu_to_le64(cpu->objectid);
|
|
}
|
|
|
|
static inline u64 btrfs_disk_key_objectid(struct btrfs_disk_key *disk)
|
|
{
|
|
return le64_to_cpu(disk->objectid);
|
|
}
|
|
|
|
static inline void btrfs_set_disk_key_objectid(struct btrfs_disk_key *disk,
|
|
u64 val)
|
|
{
|
|
disk->objectid = cpu_to_le64(val);
|
|
}
|
|
|
|
static inline u64 btrfs_disk_key_offset(struct btrfs_disk_key *disk)
|
|
{
|
|
return le64_to_cpu(disk->offset);
|
|
}
|
|
|
|
static inline void btrfs_set_disk_key_offset(struct btrfs_disk_key *disk,
|
|
u64 val)
|
|
{
|
|
disk->offset = cpu_to_le64(val);
|
|
}
|
|
|
|
static inline u32 btrfs_disk_key_flags(struct btrfs_disk_key *disk)
|
|
{
|
|
return le32_to_cpu(disk->flags);
|
|
}
|
|
|
|
static inline void btrfs_set_disk_key_flags(struct btrfs_disk_key *disk,
|
|
u32 val)
|
|
{
|
|
disk->flags = cpu_to_le32(val);
|
|
}
|
|
|
|
static inline u32 btrfs_key_type(struct btrfs_key *key)
|
|
{
|
|
return key->flags & BTRFS_KEY_TYPE_MASK;
|
|
}
|
|
|
|
static inline u32 btrfs_disk_key_type(struct btrfs_disk_key *key)
|
|
{
|
|
return le32_to_cpu(key->flags) & BTRFS_KEY_TYPE_MASK;
|
|
}
|
|
|
|
static inline void btrfs_set_key_type(struct btrfs_key *key, u32 type)
|
|
{
|
|
BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
|
|
key->flags = (key->flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
|
|
}
|
|
|
|
static inline void btrfs_set_disk_key_type(struct btrfs_disk_key *key, u32 type)
|
|
{
|
|
u32 flags = btrfs_disk_key_flags(key);
|
|
BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
|
|
flags = (flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
|
|
btrfs_set_disk_key_flags(key, flags);
|
|
}
|
|
|
|
|
|
|
|
static inline u64 btrfs_header_blocknr(struct btrfs_header *h)
|
|
{
|
|
return le64_to_cpu(h->blocknr);
|
|
}
|
|
|
|
static inline void btrfs_set_header_blocknr(struct btrfs_header *h, u64 blocknr)
|
|
{
|
|
h->blocknr = cpu_to_le64(blocknr);
|
|
}
|
|
|
|
static inline u64 btrfs_header_parentid(struct btrfs_header *h)
|
|
{
|
|
return le64_to_cpu(h->parentid);
|
|
}
|
|
|
|
static inline void btrfs_set_header_parentid(struct btrfs_header *h,
|
|
u64 parentid)
|
|
{
|
|
h->parentid = cpu_to_le64(parentid);
|
|
}
|
|
|
|
static inline u16 btrfs_header_nritems(struct btrfs_header *h)
|
|
{
|
|
return le16_to_cpu(h->nritems);
|
|
}
|
|
|
|
static inline void btrfs_set_header_nritems(struct btrfs_header *h, u16 val)
|
|
{
|
|
h->nritems = cpu_to_le16(val);
|
|
}
|
|
|
|
static inline u16 btrfs_header_flags(struct btrfs_header *h)
|
|
{
|
|
return le16_to_cpu(h->flags);
|
|
}
|
|
|
|
static inline void btrfs_set_header_flags(struct btrfs_header *h, u16 val)
|
|
{
|
|
h->flags = cpu_to_le16(val);
|
|
}
|
|
|
|
static inline int btrfs_header_level(struct btrfs_header *h)
|
|
{
|
|
return btrfs_header_flags(h) & (BTRFS_MAX_LEVEL - 1);
|
|
}
|
|
|
|
static inline void btrfs_set_header_level(struct btrfs_header *h, int level)
|
|
{
|
|
u16 flags;
|
|
BUG_ON(level > BTRFS_MAX_LEVEL);
|
|
flags = btrfs_header_flags(h) & ~(BTRFS_MAX_LEVEL - 1);
|
|
btrfs_set_header_flags(h, flags | level);
|
|
}
|
|
|
|
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 u32 btrfs_super_blocksize(struct btrfs_super_block *s)
|
|
{
|
|
return le32_to_cpu(s->blocksize);
|
|
}
|
|
|
|
static inline void btrfs_set_super_blocksize(struct btrfs_super_block *s,
|
|
u32 val)
|
|
{
|
|
s->blocksize = cpu_to_le32(val);
|
|
}
|
|
|
|
static inline u8 *btrfs_leaf_data(struct btrfs_leaf *l)
|
|
{
|
|
return (u8 *)l->items;
|
|
}
|
|
/* helper function to cast into the data area of the leaf. */
|
|
#define btrfs_item_ptr(leaf, slot, type) \
|
|
((type *)(btrfs_leaf_data(leaf) + \
|
|
btrfs_item_offset((leaf)->items + (slot))))
|
|
|
|
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);
|
|
int btrfs_search_slot(struct btrfs_root *root, struct btrfs_key *key,
|
|
struct btrfs_path *p, int ins_len, int cow);
|
|
void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
|
|
void btrfs_init_path(struct btrfs_path *p);
|
|
int btrfs_del_item(struct btrfs_root *root, struct btrfs_path *path);
|
|
int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *key,
|
|
void *data, u32 data_size);
|
|
int btrfs_insert_empty_item(struct btrfs_root *root, struct btrfs_path *path,
|
|
struct btrfs_key *cpu_key, u32 data_size);
|
|
int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
|
|
int btrfs_leaf_free_space(struct btrfs_root *root, 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);
|
|
int btrfs_insert_dir_item(struct btrfs_root *root, char *name, int name_len,
|
|
u64 dir, u64 objectid, u8 type);
|
|
int btrfs_lookup_dir_item(struct btrfs_root *root, struct btrfs_path *path,
|
|
u64 dir, char *name, int name_len, int mod);
|
|
int btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path,
|
|
char *name, int name_len);
|
|
#endif
|