From e5f19a82d8370a2935a932d369ac44f05960e4f1 Mon Sep 17 00:00:00 2001
From: pigeonmoelleux <pigeonmoelleux@crans.org>
Date: Sat, 20 May 2023 00:00:30 +0200
Subject: [PATCH] feat(fs): ext2 block group description + inodes
---
src/fs/ext2/{superblock.rs => block.rs} | 28 ++-
src/fs/ext2/inode.rs | 217 ++++++++++++++++++++++++
src/fs/ext2/mod.rs | 4 +-
src/fs/node.rs | 31 +++-
4 files changed, 276 insertions(+), 4 deletions(-)
rename src/fs/ext2/{superblock.rs => block.rs} (91%)
create mode 100644 src/fs/ext2/inode.rs
diff --git a/src/fs/ext2/superblock.rs b/src/fs/ext2/block.rs
similarity index 91%
rename from src/fs/ext2/superblock.rs
rename to src/fs/ext2/block.rs
index 9ebe521..8ecfaeb 100644
--- a/src/fs/ext2/superblock.rs
+++ b/src/fs/ext2/block.rs
@@ -1,6 +1,6 @@
-//! Interface with the superblock
+//! Interface with the superblock and the block group descriptor table
//!
-//! See the [OSdev wiki](https://wiki.osdev.org/Ext2#Superblock) for more informations
+//! See the [OSdev wiki](https://wiki.osdev.org/Ext2) for more informations
use bitflags::bitflags;
use log::error;
@@ -272,3 +272,27 @@ bitflags! {
const BINARY_TREE = 0x0004;
}
}
+
+/// Contains a descriptor for each block group in the file system.
+#[repr(packed)]
+#[derive(Debug)]
+#[allow(clippy::module_name_repetitions)]
+pub struct BlockGroupDescriptor {
+ /// Block address of block usage bitmap
+ pub block_usage_bitmap_block_address: u32,
+
+ /// Block address of inode usage bitmap
+ pub inode_usage_bitmap_block_address: u32,
+
+ /// Starting block address of inode table
+ pub inode_table_starting_block_address: u32,
+
+ /// Number of unallocated blocks in group
+ pub total_unallocated_blocks: u16,
+
+ /// Number of unallocated inodes in group
+ pub total_unallocated_inodes: u16,
+
+ /// Number of directories in group
+ pub total_dir: u16,
+}
diff --git a/src/fs/ext2/inode.rs b/src/fs/ext2/inode.rs
new file mode 100644
index 0000000..4673a65
--- /dev/null
+++ b/src/fs/ext2/inode.rs
@@ -0,0 +1,217 @@
+//! Interface with the Inodes
+//!
+//! See the [OSdev wiki](https://wiki.osdev.org/Ext2#Inodes) for more informations
+
+use bitflags::bitflags;
+
+/// General structure of an ext2 inode
+#[derive(Debug)]
+pub struct Inode {
+ /// Type and Permissions
+ pub type_and_permissions: u16,
+
+ /// User ID
+ pub user_id: u16,
+
+ /// Lower 32 bits of size in bytes
+ pub lower_truncation_byte_size: u32,
+
+ /// Last Access Time (in POSIX time)
+ pub last_access_time: u32,
+
+ /// Creation Time (in POSIX time)
+ pub creation_time: u32,
+
+ /// Last Modification time (in POSIX time)
+ pub last_modification_time: u32,
+
+ /// Deletion time (in POSIX time)
+ pub deletion_time: u32,
+
+ /// Group ID
+ pub group_id: u16,
+
+ /// Count of hard links (directory entries) to this inode. When this reaches 0, the data blocks are marked as unallocated.
+ pub total_hard_links: u16,
+
+ /// Count of disk sectors (not Ext2 blocks) in use by this inode, not counting the actual inode structure nor directory entries
+ /// linking to the inode.
+ pub total_disk_sectors: u32,
+
+ /// Flags
+ pub flags: u32,
+
+ /// Operating System Specific value #1
+ pub os_specific_1: u32,
+
+ /// Direct Block Pointer 0
+ pub dbp00: u32,
+
+ /// Direct Block Pointer 1
+ pub dbp01: u32,
+
+ /// Direct Block Pointer 2
+ pub dbp02: u32,
+
+ /// Direct Block Pointer 3
+ pub dbp03: u32,
+
+ /// Direct Block Pointer 4
+ pub dbp04: u32,
+
+ /// Direct Block Pointer 5
+ pub dbp05: u32,
+
+ /// Direct Block Pointer 6
+ pub dbp06: u32,
+
+ /// Direct Block Pointer 7
+ pub dbp07: u32,
+
+ /// Direct Block Pointer 8
+ pub dbp08: u32,
+
+ /// Direct Block Pointer 9
+ pub dbp09: u32,
+
+ /// Direct Block Pointer 10
+ pub dbp10: u32,
+
+ /// Direct Block Pointer 11
+ pub dbp11: u32,
+
+ /// Singly Indirect Block Pointer (Points to a block that is a list of block pointers to data)
+ pub singly_indirect_block_pointer: u32,
+
+ /// Doubly Indirect Block Pointer (Points to a block that is a list of block pointers to Singly Indirect Blocks)
+ pub doubly_indirect_block_pointer: u32,
+
+ /// Triply Indirect Block Pointer (Points to a block that is a list of block pointers to Doubly Indirect Blocks)
+ pub triply_indirect_block_pointer: u32,
+
+ /// Generation number (Primarily used for NFS)
+ pub generation_number: u32,
+
+ /// In Ext2 version 0, this field is reserved. In version >= 1, Extended attribute block (File ACL).
+ pub extended_attribute_block: u32,
+
+ /// In Ext2 version 0, this field is reserved. In version >= 1, Upper 32 bits of file size (if feature bit set) if it's a file,
+ /// Directory ACL if it's a directory
+ pub higher_truncation_byte_size_or_directory_acl: u32,
+
+ /// Block address of fragment
+ pub fragment_block_address: u32,
+
+ /// Operating System Specific value #2
+ pub os_specific_2: [u8; 12],
+}
+
+bitflags! {
+ /// Indicators of the inode type and permissions
+ ///
+ /// The type indicator occupies the top hex digit (bits 15 to 12).
+ ///
+ /// The permission indicator occupies the bottom 12 bits.
+ pub struct TypePermissions: u16 {
+ // Types
+
+ /// FIFO
+ const FIFO = 0x1000;
+
+ /// Character device
+ const CHARACTER_DEVICE = 0x2000;
+
+ /// Directory
+ const DIRECTORY = 0x4000;
+
+ /// Block device
+ const BLOCK_DEVICE = 0x6000;
+
+ /// Regular file
+ const FILE = 0x8000;
+
+ /// Symbolic link
+ const SYMBOLIC_LINK = 0xA000;
+
+ /// Unix socket
+ const SOCKET = 0xC000;
+
+
+
+ // Permissions
+
+ /// Other - execute permission
+ const OTHER_X = 0x0001;
+
+ /// Other - write permission
+ const OTHER_W = 0x0002;
+
+ /// Other - read permission
+ const OTHER_R = 0x0004;
+
+ /// Group - execute permission
+ const GROUP_X = 0x0008;
+
+ /// Group - write permission
+ const GROUP_W = 0x0010;
+
+ /// Group - read permission
+ const GROUP_R = 0x0020;
+
+ /// User - execute permission
+ const USER_X = 0x0040;
+
+ /// User - write permission
+ const USER_W = 0x0080;
+
+ /// User - read permission
+ const USER_R = 0x0100;
+
+ /// Sticky bit
+ const STICKY = 0x0200;
+
+ /// Set group ID
+ const SET_GROUP_ID = 0x0400;
+
+ /// Set user ID
+ const SET_USER_ID = 0x0800;
+ }
+}
+
+bitflags! {
+ /// Inode Flags
+ pub struct Flags: u32 {
+ /// Secure deletion (not used)
+ const SECURE_DELETION = 0x00000001;
+
+ /// Keep a copy of data when deleted (not used)
+ const DELETION_KEEP_DATA_COPY = 0x00000002;
+
+ /// File compression (not used)
+ const FILE_COMPRESSION = 0x00000004;
+
+ /// Synchronous updates—new data is written immediately to disk
+ const SYNCHRONOUS_UPDATES = 0x00000008;
+
+ /// Immutable file (content cannot be changed)
+ const IMMUTABLE_FILE = 0x00000010;
+
+ /// Append only
+ const APPEND_ONLY = 0x00000020;
+
+ /// File is not included in `dump` command
+ const DUMP_EXCLUDED = 0x00000040;
+
+ /// Last accessed time should not updated
+ const LAST_ACCESSED_TIME_UPDATE_DISABLE = 0x00000080;
+
+ /// Hash indexed directory
+ const HASHED_INDEXED_DIR = 0x00010000;
+
+ /// AFS directory
+ const AFS_DIR = 0x00020000;
+
+ /// Journal file data
+ const JOURNAL_FILE_DATA = 0x000400000;
+ }
+}
diff --git a/src/fs/ext2/mod.rs b/src/fs/ext2/mod.rs
index 2dcff89..9f2c900 100644
--- a/src/fs/ext2/mod.rs
+++ b/src/fs/ext2/mod.rs
@@ -1,4 +1,6 @@
//! Implementation of the Second Extended Filesystem (ext2fs) filesystem
#[allow(clippy::same_name_method)]
-mod superblock;
+mod block;
+#[allow(clippy::same_name_method)]
+mod inode;
diff --git a/src/fs/node.rs b/src/fs/node.rs
index 15debe7..85d0386 100644
--- a/src/fs/node.rs
+++ b/src/fs/node.rs
@@ -18,8 +18,9 @@ use crate::kernel::device::block::Manipulation;
/// Type alias for a thread-safe shared reference behind a mutex
pub type Ref<T> = Arc<Mutex<T>>;
-/// Enumeration of possible node kinds : file, directory or symbolic link
+/// Enumeration of possible inode types
#[derive(Debug, Clone, Copy)]
+#[allow(unused)]
pub enum Kind {
/// Storage unit of a filesystem
File,
@@ -29,6 +30,18 @@ pub enum Kind {
/// Node pointing towards an other node in the filesystem
Symlink,
+
+ /// FIFO
+ Fifo,
+
+ /// An inode that refers to a device communicating by sending chars (bytes) of data
+ CharacterDevice,
+
+ /// An inode that refers to a device communicating by sending blocks of data
+ BlockDevice,
+
+ /// Communication flow between two processes
+ UnixSocket,
}
/// Enumeration of possible nodes
@@ -42,6 +55,18 @@ pub enum Node {
/// A reference to a symbolic link
Symlink(Ref<dyn Symlink>),
+
+ /// A reference to a FIFO
+ Fifo(Ref<dyn Interface>),
+
+ /// A reference to a character device
+ CharacterDevice(Ref<dyn Interface>),
+
+ /// A reference to a block device
+ BlockDevice(Ref<dyn Interface>),
+
+ /// A reference to a Unix socket
+ UnixSocket(Ref<dyn Interface>),
}
impl From<Node> for Kind {
@@ -50,6 +75,10 @@ impl From<Node> for Kind {
Node::File(_) => Self::File,
Node::Directory(_) => Self::Directory,
Node::Symlink(_) => Self::Symlink,
+ Node::Fifo(_) => Self::Fifo,
+ Node::CharacterDevice(_) => Self::CharacterDevice,
+ Node::BlockDevice(_) => Self::BlockDevice,
+ Node::UnixSocket(_) => Self::UnixSocket,
}
}
}
--
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