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use std::mem;
use diskformat::*;
#[ repr (C, packed) ]
#[ derive (Copy) ]
pub struct BtrfsSuperblock {
checksum: BtrfsChecksum,
fs_uuid: BtrfsUuid,
physical_address: u64,
flags: u64,
magic: [u8; 0x8],
generation: u64,
root_tree_logical_address: u64,
chunk_tree_logical_address: u64,
log_tree_logical_address: u64,
log_root_transid: u64,
total_bytes: u64,
bytes_used: u64,
root_dir_objectid: u64,
num_devices: u64,
sector_size: u32,
node_size: u32,
leaf_size: u32,
stripesize: u32,
system_chunks_size: u32,
chunk_root_generation: u64,
compat_flags: u64,
compat_ro_flags: u64,
incompat_flags: u64,
csum_type: u16,
root_level: u8,
chunk_root_level: u8,
log_root_level: u8,
dev_item: BtrfsDevItem,
label: BtrfsLabel,
reserved: [u8; 0x100],
system_chunks: [u8; 0x800],
unused: [u8; 0x4d5],
}
pub struct BtrfsSuperblockSystemChunks <'a> {
_superblock: & 'a BtrfsSuperblock,
address: * const u8,
end_address: * const u8,
}
impl BtrfsSuperblock {
pub fn fs_uuid (& self) -> BtrfsUuid {
self.fs_uuid
}
pub fn system_chunks (& self) -> BtrfsSuperblockSystemChunks {
let start_address =
self.system_chunks.as_ptr ();
let end_address = unsafe {
start_address.offset (
self.system_chunks_size as isize,
)
};
BtrfsSuperblockSystemChunks {
_superblock: self,
address: start_address,
end_address: end_address,
}
}
pub fn system_logical_to_physical (
& self,
logical_address: u64,
) -> Option <(u64, u64)> {
for system_chunk in self.system_chunks () {
if logical_address < system_chunk.key ().offset ()
|| logical_address >= (
system_chunk.key ().offset ()
+ system_chunk.data ().chunk_size ()
) {
continue;
}
let system_chunk_stripe =
system_chunk.stripes () [0];
return Some (
(
system_chunk_stripe.device_id (),
logical_address
- system_chunk.key ().offset ()
+ system_chunk_stripe.offset (),
)
);
}
None
}
pub fn magic (& self) -> [u8; 0x8] {
self.magic
}
pub fn root_tree_logical_address (& self) -> u64 {
self.root_tree_logical_address
}
pub fn chunk_tree_logical_address (& self) -> u64 {
self.chunk_tree_logical_address
}
pub fn sector_size (& self) -> u32 {
self.sector_size
}
pub fn node_size (& self) -> u32 {
self.node_size
}
pub fn leaf_size (& self) -> u32 {
self.leaf_size
}
pub fn dev_item (& self) -> & BtrfsDevItem {
& self.dev_item
}
}
impl Clone for BtrfsSuperblock {
fn clone (
& self,
) -> Self {
* self
}
}
impl <'a> Iterator for BtrfsSuperblockSystemChunks <'a> {
type Item = BtrfsChunkItemSimple <'a>;
fn next (
& mut self,
) -> Option <BtrfsChunkItemSimple <'a>> {
if self.address < self.end_address {
let chunk_item_key = unsafe {
& * (
self.address
as * const BtrfsKey
)
};
self.address = unsafe {
self.address.offset (
mem::size_of::<BtrfsKey> () as isize,
)
};
let chunk_item_data = unsafe {
& * (
self.address
as * const BtrfsChunkItemData
)
};
self.address = unsafe {
self.address.offset (
mem::size_of::<BtrfsChunkItemData> () as isize,
)
};
self.address = unsafe {
self.address.offset (
mem::size_of::<BtrfsChunkItemStripeData> () as isize
* chunk_item_data.num_stripes () as isize,
)
};
Some (
BtrfsChunkItemSimple::new (
chunk_item_key,
chunk_item_data,
).expect ("Invalid chunk item")
)
} else {
None
}
}
}