| Message ID | 20240916135634.98554-6-toolmanp@tlmp.cc (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | erofs: introduce Rust implementation | expand |
On 2024/9/16 21:56, Yiyang Wu via Linux-erofs wrote: > > This patch introduces the same on-disk erofs data structure > in rust and also introduces multiple helpers for inode i_format > and chunk_indexing and later can be used to implement map_blocks. > > Signed-off-by: Yiyang Wu <toolmanp@tlmp.cc> > --- > fs/erofs/rust/erofs_sys.rs | 1 + > fs/erofs/rust/erofs_sys/inode.rs | 291 +++++++++++++++++++++++++++++++ > 2 files changed, 292 insertions(+) > create mode 100644 fs/erofs/rust/erofs_sys/inode.rs > > diff --git a/fs/erofs/rust/erofs_sys.rs b/fs/erofs/rust/erofs_sys.rs > index 6f3c12665ed6..34267ec7772d 100644 > --- a/fs/erofs/rust/erofs_sys.rs > +++ b/fs/erofs/rust/erofs_sys.rs > @@ -24,6 +24,7 @@ > pub(crate) type PosixResult<T> = Result<T, Errno>; > > pub(crate) mod errnos; > +pub(crate) mod inode; > pub(crate) mod superblock; > pub(crate) mod xattrs; > pub(crate) use errnos::Errno; > diff --git a/fs/erofs/rust/erofs_sys/inode.rs b/fs/erofs/rust/erofs_sys/inode.rs > new file mode 100644 > index 000000000000..1762023e97f8 > --- /dev/null > +++ b/fs/erofs/rust/erofs_sys/inode.rs > @@ -0,0 +1,291 @@ > +use super::xattrs::*; > +use super::*; > +use core::ffi::*; > +use core::mem::size_of; > + > +/// Represents the compact bitfield of the Erofs Inode format. > +#[repr(transparent)] > +#[derive(Clone, Copy)] > +pub(crate) struct Format(u16); > + > +pub(crate) const INODE_VERSION_MASK: u16 = 0x1; > +pub(crate) const INODE_VERSION_BIT: u16 = 0; > + > +pub(crate) const INODE_LAYOUT_BIT: u16 = 1; > +pub(crate) const INODE_LAYOUT_MASK: u16 = 0x7; > + > +/// Helper macro to extract property from the bitfield. > +macro_rules! extract { > + ($name: expr, $bit: expr, $mask: expr) => { > + ($name >> $bit) & ($mask) > + }; > +} > + > +/// The Version of the Inode which represents whether this inode is extended or compact. > +/// Extended inodes have more infos about nlinks + mtime. > +/// This is documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inodes > +#[repr(C)] > +#[derive(Clone, Copy)] > +pub(crate) enum Version { > + Compat, > + Extended, > + Unknown, > +} > + > +/// Represents the data layout backed by the Inode. > +/// As Documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inode-data-layouts > +#[repr(C)] > +#[derive(Clone, Copy, PartialEq)] > +pub(crate) enum Layout { > + FlatPlain, > + CompressedFull, > + FlatInline, > + CompressedCompact, > + Chunk, > + Unknown, > +} > + > +#[repr(C)] > +#[allow(non_camel_case_types)] > +#[derive(Clone, Copy, Debug, PartialEq)] > +pub(crate) enum Type { > + Regular, > + Directory, > + Link, > + Character, > + Block, > + Fifo, > + Socket, > + Unknown, > +} > + > +/// This is format extracted from i_format bit representation. > +/// This includes various infos and specs about the inode. > +impl Format { > + pub(crate) fn version(&self) -> Version { > + match extract!(self.0, INODE_VERSION_BIT, INODE_VERSION_MASK) { > + 0 => Version::Compat, > + 1 => Version::Extended, > + _ => Version::Unknown, > + } > + } > + > + pub(crate) fn layout(&self) -> Layout { > + match extract!(self.0, INODE_LAYOUT_BIT, INODE_LAYOUT_MASK) { > + 0 => Layout::FlatPlain, > + 1 => Layout::CompressedFull, > + 2 => Layout::FlatInline, > + 3 => Layout::CompressedCompact, > + 4 => Layout::Chunk, > + _ => Layout::Unknown, > + } > + } > +} > + > +/// Represents the compact inode which resides on-disk. > +/// This is documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inodes > +#[repr(C)] > +#[derive(Clone, Copy)] > +pub(crate) struct CompactInodeInfo { > + pub(crate) i_format: Format, > + pub(crate) i_xattr_icount: u16, > + pub(crate) i_mode: u16, > + pub(crate) i_nlink: u16, > + pub(crate) i_size: u32, > + pub(crate) i_reserved: [u8; 4], > + pub(crate) i_u: [u8; 4], > + pub(crate) i_ino: u32, > + pub(crate) i_uid: u16, > + pub(crate) i_gid: u16, > + pub(crate) i_reserved2: [u8; 4], > +} > + > +/// Represents the extended inode which resides on-disk. > +/// This is documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inodes > +#[repr(C)] > +#[derive(Clone, Copy)] > +pub(crate) struct ExtendedInodeInfo { > + pub(crate) i_format: Format, > + pub(crate) i_xattr_icount: u16, > + pub(crate) i_mode: u16, > + pub(crate) i_reserved: [u8; 2], > + pub(crate) i_size: u64, > + pub(crate) i_u: [u8; 4], > + pub(crate) i_ino: u32, > + pub(crate) i_uid: u32, > + pub(crate) i_gid: u32, > + pub(crate) i_mtime: u64, > + pub(crate) i_mtime_nsec: u32, > + pub(crate) i_nlink: u32, > + pub(crate) i_reserved2: [u8; 16], > +} > + > +/// Represents the inode info which is either compact or extended. > +#[derive(Clone, Copy)] > +pub(crate) enum InodeInfo { > + Extended(ExtendedInodeInfo), > + Compact(CompactInodeInfo), > +} > + > +pub(crate) const CHUNK_BLKBITS_MASK: u16 = 0x1f; > +pub(crate) const CHUNK_FORMAT_INDEX_BIT: u16 = 0x20; > + > +/// Represents on-disk chunk index of the file backing inode. > +#[repr(C)] > +#[derive(Clone, Copy, Debug)] > +pub(crate) struct ChunkIndex { > + pub(crate) advise: u16, > + pub(crate) device_id: u16, > + pub(crate) blkaddr: u32, > +} > + > +impl From<[u8; 8]> for ChunkIndex { > + fn from(u: [u8; 8]) -> Self { > + let advise = u16::from_le_bytes([u[0], u[1]]); > + let device_id = u16::from_le_bytes([u[2], u[3]]); > + let blkaddr = u32::from_le_bytes([u[4], u[5], u[6], u[7]]); > + ChunkIndex { > + advise, > + device_id, > + blkaddr, > + } > + } > +} > + > +/// Chunk format used for indicating the chunkbits and chunkindex. > +#[repr(C)] > +#[derive(Clone, Copy, Debug)] > +pub(crate) struct ChunkFormat(pub(crate) u16); > + > +impl ChunkFormat { > + pub(crate) fn is_chunkindex(&self) -> bool { > + self.0 & CHUNK_FORMAT_INDEX_BIT != 0 > + } > + pub(crate) fn chunkbits(&self) -> u16 { > + self.0 & CHUNK_BLKBITS_MASK > + } It is recommended to add blank lines between code blocks. This problem exists in many places in this patch set. > +} > + > +/// Represents the inode spec which is either data or device. > +#[derive(Clone, Copy, Debug)] > +#[repr(u32)] > +pub(crate) enum Spec { > + Chunk(ChunkFormat), > + RawBlk(u32), > + Device(u32), > + CompressedBlocks(u32), > + Unknown, > +} > + > +/// Convert the spec from the format of the inode based on the layout. > +impl From<(&[u8; 4], Layout)> for Spec { > + fn from(value: (&[u8; 4], Layout)) -> Self { > + match value.1 { > + Layout::FlatInline | Layout::FlatPlain => Spec::RawBlk(u32::from_le_bytes(*value.0)), > + Layout::CompressedFull | Layout::CompressedCompact => { > + Spec::CompressedBlocks(u32::from_le_bytes(*value.0)) > + } > + Layout::Chunk => Self::Chunk(ChunkFormat(u16::from_le_bytes([value.0[0], value.0[1]]))), > + // We don't support compressed inlines or compressed chunks currently. > + _ => Spec::Unknown, > + } > + } > +} > + > +/// Helper functions for Inode Info. > +impl InodeInfo { > + const S_IFMT: u16 = 0o170000; > + const S_IFSOCK: u16 = 0o140000; > + const S_IFLNK: u16 = 0o120000; > + const S_IFREG: u16 = 0o100000; > + const S_IFBLK: u16 = 0o60000; > + const S_IFDIR: u16 = 0o40000; > + const S_IFCHR: u16 = 0o20000; > + const S_IFIFO: u16 = 0o10000; > + const S_ISUID: u16 = 0o4000; > + const S_ISGID: u16 = 0o2000; > + const S_ISVTX: u16 = 0o1000; > + pub(crate) fn ino(&self) -> u32 { > + match self { > + Self::Extended(extended) => extended.i_ino, > + Self::Compact(compact) => compact.i_ino, > + } > + } > + > + pub(crate) fn format(&self) -> Format { > + match self { > + Self::Extended(extended) => extended.i_format, > + Self::Compact(compact) => compact.i_format, > + } > + } > + > + pub(crate) fn file_size(&self) -> Off { > + match self { > + Self::Extended(extended) => extended.i_size, > + Self::Compact(compact) => compact.i_size as u64, > + } > + } > + > + pub(crate) fn inode_size(&self) -> Off { > + match self { > + Self::Extended(_) => 64, > + Self::Compact(_) => 32, Self::Extended(_) => size_of::<ExtendedInodeInfo>() as Off, Self::Compact(_) => size_of::<CompactInodeInfo>() as Off, > + } > + } > + > + pub(crate) fn spec(&self) -> Spec { > + let mode = match self { > + Self::Extended(extended) => extended.i_mode, > + Self::Compact(compact) => compact.i_mode, > + }; > + > + let u = match self { > + Self::Extended(extended) => &extended.i_u, > + Self::Compact(compact) => &compact.i_u, > + }; > + > + match mode & 0o170000 { > + 0o40000 | 0o100000 | 0o120000 => Spec::from((u, self.format().layout())), match mode & Self::S_IFMT { Self::S_IFDIR | Self::S_IFREG | Self::S_IFLNK => Spec::from((u, self.format().layout())), > + // We don't support device inodes currently. > + _ => Spec::Unknown, > + } > + } > + > + pub(crate) fn inode_type(&self) -> Type { > + let mode = match self { > + Self::Extended(extended) => extended.i_mode, > + Self::Compact(compact) => compact.i_mode, > + }; > + match mode & Self::S_IFMT { > + Self::S_IFDIR => Type::Directory, // Directory > + Self::S_IFREG => Type::Regular, // Regular File > + Self::S_IFLNK => Type::Link, // Symbolic Link > + Self::S_IFIFO => Type::Fifo, // FIFO > + Self::S_IFSOCK => Type::Socket, // Socket > + Self::S_IFBLK => Type::Block, // Block > + Self::S_IFCHR => Type::Character, // Character > + _ => Type::Unknown, > + } > + } > + > + pub(crate) fn xattr_size(&self) -> Off { > + match self { > + Self::Extended(extended) => { if extended.i_xattr_icount == 0 { return 0; } to avoid subtract with overflow. Thanks, Jianan > + size_of::<XAttrSharedEntrySummary>() as Off > + + (size_of::<c_int>() as Off) * (extended.i_xattr_icount as Off - 1) > + } > + Self::Compact(_) => 0, > + } > + } > + > + pub(crate) fn xattr_count(&self) -> u16 { > + match self { > + Self::Extended(extended) => extended.i_xattr_icount, > + Self::Compact(compact) => compact.i_xattr_icount, > + } > + } > +} > + > +pub(crate) type CompactInodeInfoBuf = [u8; size_of::<CompactInodeInfo>()]; > +pub(crate) type ExtendedInodeInfoBuf = [u8; size_of::<ExtendedInodeInfo>()]; > +pub(crate) const DEFAULT_INODE_BUF: ExtendedInodeInfoBuf = [0; size_of::<ExtendedInodeInfo>()]; > -- > 2.46.0 >
diff --git a/fs/erofs/rust/erofs_sys.rs b/fs/erofs/rust/erofs_sys.rs index 6f3c12665ed6..34267ec7772d 100644 --- a/fs/erofs/rust/erofs_sys.rs +++ b/fs/erofs/rust/erofs_sys.rs @@ -24,6 +24,7 @@ pub(crate) type PosixResult<T> = Result<T, Errno>; pub(crate) mod errnos; +pub(crate) mod inode; pub(crate) mod superblock; pub(crate) mod xattrs; pub(crate) use errnos::Errno; diff --git a/fs/erofs/rust/erofs_sys/inode.rs b/fs/erofs/rust/erofs_sys/inode.rs new file mode 100644 index 000000000000..1762023e97f8 --- /dev/null +++ b/fs/erofs/rust/erofs_sys/inode.rs @@ -0,0 +1,291 @@ +use super::xattrs::*; +use super::*; +use core::ffi::*; +use core::mem::size_of; + +/// Represents the compact bitfield of the Erofs Inode format. +#[repr(transparent)] +#[derive(Clone, Copy)] +pub(crate) struct Format(u16); + +pub(crate) const INODE_VERSION_MASK: u16 = 0x1; +pub(crate) const INODE_VERSION_BIT: u16 = 0; + +pub(crate) const INODE_LAYOUT_BIT: u16 = 1; +pub(crate) const INODE_LAYOUT_MASK: u16 = 0x7; + +/// Helper macro to extract property from the bitfield. +macro_rules! extract { + ($name: expr, $bit: expr, $mask: expr) => { + ($name >> $bit) & ($mask) + }; +} + +/// The Version of the Inode which represents whether this inode is extended or compact. +/// Extended inodes have more infos about nlinks + mtime. +/// This is documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inodes +#[repr(C)] +#[derive(Clone, Copy)] +pub(crate) enum Version { + Compat, + Extended, + Unknown, +} + +/// Represents the data layout backed by the Inode. +/// As Documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inode-data-layouts +#[repr(C)] +#[derive(Clone, Copy, PartialEq)] +pub(crate) enum Layout { + FlatPlain, + CompressedFull, + FlatInline, + CompressedCompact, + Chunk, + Unknown, +} + +#[repr(C)] +#[allow(non_camel_case_types)] +#[derive(Clone, Copy, Debug, PartialEq)] +pub(crate) enum Type { + Regular, + Directory, + Link, + Character, + Block, + Fifo, + Socket, + Unknown, +} + +/// This is format extracted from i_format bit representation. +/// This includes various infos and specs about the inode. +impl Format { + pub(crate) fn version(&self) -> Version { + match extract!(self.0, INODE_VERSION_BIT, INODE_VERSION_MASK) { + 0 => Version::Compat, + 1 => Version::Extended, + _ => Version::Unknown, + } + } + + pub(crate) fn layout(&self) -> Layout { + match extract!(self.0, INODE_LAYOUT_BIT, INODE_LAYOUT_MASK) { + 0 => Layout::FlatPlain, + 1 => Layout::CompressedFull, + 2 => Layout::FlatInline, + 3 => Layout::CompressedCompact, + 4 => Layout::Chunk, + _ => Layout::Unknown, + } + } +} + +/// Represents the compact inode which resides on-disk. +/// This is documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inodes +#[repr(C)] +#[derive(Clone, Copy)] +pub(crate) struct CompactInodeInfo { + pub(crate) i_format: Format, + pub(crate) i_xattr_icount: u16, + pub(crate) i_mode: u16, + pub(crate) i_nlink: u16, + pub(crate) i_size: u32, + pub(crate) i_reserved: [u8; 4], + pub(crate) i_u: [u8; 4], + pub(crate) i_ino: u32, + pub(crate) i_uid: u16, + pub(crate) i_gid: u16, + pub(crate) i_reserved2: [u8; 4], +} + +/// Represents the extended inode which resides on-disk. +/// This is documented in https://erofs.docs.kernel.org/en/latest/core_ondisk.html#inodes +#[repr(C)] +#[derive(Clone, Copy)] +pub(crate) struct ExtendedInodeInfo { + pub(crate) i_format: Format, + pub(crate) i_xattr_icount: u16, + pub(crate) i_mode: u16, + pub(crate) i_reserved: [u8; 2], + pub(crate) i_size: u64, + pub(crate) i_u: [u8; 4], + pub(crate) i_ino: u32, + pub(crate) i_uid: u32, + pub(crate) i_gid: u32, + pub(crate) i_mtime: u64, + pub(crate) i_mtime_nsec: u32, + pub(crate) i_nlink: u32, + pub(crate) i_reserved2: [u8; 16], +} + +/// Represents the inode info which is either compact or extended. +#[derive(Clone, Copy)] +pub(crate) enum InodeInfo { + Extended(ExtendedInodeInfo), + Compact(CompactInodeInfo), +} + +pub(crate) const CHUNK_BLKBITS_MASK: u16 = 0x1f; +pub(crate) const CHUNK_FORMAT_INDEX_BIT: u16 = 0x20; + +/// Represents on-disk chunk index of the file backing inode. +#[repr(C)] +#[derive(Clone, Copy, Debug)] +pub(crate) struct ChunkIndex { + pub(crate) advise: u16, + pub(crate) device_id: u16, + pub(crate) blkaddr: u32, +} + +impl From<[u8; 8]> for ChunkIndex { + fn from(u: [u8; 8]) -> Self { + let advise = u16::from_le_bytes([u[0], u[1]]); + let device_id = u16::from_le_bytes([u[2], u[3]]); + let blkaddr = u32::from_le_bytes([u[4], u[5], u[6], u[7]]); + ChunkIndex { + advise, + device_id, + blkaddr, + } + } +} + +/// Chunk format used for indicating the chunkbits and chunkindex. +#[repr(C)] +#[derive(Clone, Copy, Debug)] +pub(crate) struct ChunkFormat(pub(crate) u16); + +impl ChunkFormat { + pub(crate) fn is_chunkindex(&self) -> bool { + self.0 & CHUNK_FORMAT_INDEX_BIT != 0 + } + pub(crate) fn chunkbits(&self) -> u16 { + self.0 & CHUNK_BLKBITS_MASK + } +} + +/// Represents the inode spec which is either data or device. +#[derive(Clone, Copy, Debug)] +#[repr(u32)] +pub(crate) enum Spec { + Chunk(ChunkFormat), + RawBlk(u32), + Device(u32), + CompressedBlocks(u32), + Unknown, +} + +/// Convert the spec from the format of the inode based on the layout. +impl From<(&[u8; 4], Layout)> for Spec { + fn from(value: (&[u8; 4], Layout)) -> Self { + match value.1 { + Layout::FlatInline | Layout::FlatPlain => Spec::RawBlk(u32::from_le_bytes(*value.0)), + Layout::CompressedFull | Layout::CompressedCompact => { + Spec::CompressedBlocks(u32::from_le_bytes(*value.0)) + } + Layout::Chunk => Self::Chunk(ChunkFormat(u16::from_le_bytes([value.0[0], value.0[1]]))), + // We don't support compressed inlines or compressed chunks currently. + _ => Spec::Unknown, + } + } +} + +/// Helper functions for Inode Info. +impl InodeInfo { + const S_IFMT: u16 = 0o170000; + const S_IFSOCK: u16 = 0o140000; + const S_IFLNK: u16 = 0o120000; + const S_IFREG: u16 = 0o100000; + const S_IFBLK: u16 = 0o60000; + const S_IFDIR: u16 = 0o40000; + const S_IFCHR: u16 = 0o20000; + const S_IFIFO: u16 = 0o10000; + const S_ISUID: u16 = 0o4000; + const S_ISGID: u16 = 0o2000; + const S_ISVTX: u16 = 0o1000; + pub(crate) fn ino(&self) -> u32 { + match self { + Self::Extended(extended) => extended.i_ino, + Self::Compact(compact) => compact.i_ino, + } + } + + pub(crate) fn format(&self) -> Format { + match self { + Self::Extended(extended) => extended.i_format, + Self::Compact(compact) => compact.i_format, + } + } + + pub(crate) fn file_size(&self) -> Off { + match self { + Self::Extended(extended) => extended.i_size, + Self::Compact(compact) => compact.i_size as u64, + } + } + + pub(crate) fn inode_size(&self) -> Off { + match self { + Self::Extended(_) => 64, + Self::Compact(_) => 32, + } + } + + pub(crate) fn spec(&self) -> Spec { + let mode = match self { + Self::Extended(extended) => extended.i_mode, + Self::Compact(compact) => compact.i_mode, + }; + + let u = match self { + Self::Extended(extended) => &extended.i_u, + Self::Compact(compact) => &compact.i_u, + }; + + match mode & 0o170000 { + 0o40000 | 0o100000 | 0o120000 => Spec::from((u, self.format().layout())), + // We don't support device inodes currently. + _ => Spec::Unknown, + } + } + + pub(crate) fn inode_type(&self) -> Type { + let mode = match self { + Self::Extended(extended) => extended.i_mode, + Self::Compact(compact) => compact.i_mode, + }; + match mode & Self::S_IFMT { + Self::S_IFDIR => Type::Directory, // Directory + Self::S_IFREG => Type::Regular, // Regular File + Self::S_IFLNK => Type::Link, // Symbolic Link + Self::S_IFIFO => Type::Fifo, // FIFO + Self::S_IFSOCK => Type::Socket, // Socket + Self::S_IFBLK => Type::Block, // Block + Self::S_IFCHR => Type::Character, // Character + _ => Type::Unknown, + } + } + + pub(crate) fn xattr_size(&self) -> Off { + match self { + Self::Extended(extended) => { + size_of::<XAttrSharedEntrySummary>() as Off + + (size_of::<c_int>() as Off) * (extended.i_xattr_icount as Off - 1) + } + Self::Compact(_) => 0, + } + } + + pub(crate) fn xattr_count(&self) -> u16 { + match self { + Self::Extended(extended) => extended.i_xattr_icount, + Self::Compact(compact) => compact.i_xattr_icount, + } + } +} + +pub(crate) type CompactInodeInfoBuf = [u8; size_of::<CompactInodeInfo>()]; +pub(crate) type ExtendedInodeInfoBuf = [u8; size_of::<ExtendedInodeInfo>()]; +pub(crate) const DEFAULT_INODE_BUF: ExtendedInodeInfoBuf = [0; size_of::<ExtendedInodeInfo>()];
This patch introduces the same on-disk erofs data structure in rust and also introduces multiple helpers for inode i_format and chunk_indexing and later can be used to implement map_blocks. Signed-off-by: Yiyang Wu <toolmanp@tlmp.cc> --- fs/erofs/rust/erofs_sys.rs | 1 + fs/erofs/rust/erofs_sys/inode.rs | 291 +++++++++++++++++++++++++++++++ 2 files changed, 292 insertions(+) create mode 100644 fs/erofs/rust/erofs_sys/inode.rs