os/fs/sysfs/
sysfs.rs

1//! Sysfs 文件系统实现
2//!
3//! 提供与 Linux 兼容的 sysfs 虚拟文件系统,暴露设备和内核信息。
4
5use alloc::string::ToString;
6use alloc::sync::Arc;
7
8use crate::vfs::{FileMode, FileSystem, FsError, Inode, StatFs};
9
10use super::inode::SysfsInode;
11
12/// Sysfs 文件系统
13pub struct SysFS {
14    root_inode: Arc<SysfsInode>,
15}
16
17impl SysFS {
18    /// 创建新的 sysfs 实例
19    pub fn new() -> Arc<Self> {
20        let root = SysfsInode::new_directory(FileMode::from_bits_truncate(
21            0o040000 | 0o555, // dr-xr-xr-x
22        ));
23
24        Arc::new(Self { root_inode: root })
25    }
26
27    /// 初始化 sysfs 树结构 (冷插拔)
28    pub fn init_tree(self: &Arc<Self>) -> Result<(), FsError> {
29        // 创建基本目录结构
30        self.create_directory_structure()?;
31
32        // 从设备注册表构建设备树
33        self.build_device_trees()?;
34
35        Ok(())
36    }
37
38    fn create_directory_structure(&self) -> Result<(), FsError> {
39        let root = &self.root_inode;
40
41        // /sys/class/
42        let class_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
43        root.add_child("class", class_dir.clone())?;
44
45        // /sys/class/block/
46        let block_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
47        class_dir.add_child("block", block_dir)?;
48
49        // /sys/class/net/
50        let net_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
51        class_dir.add_child("net", net_dir)?;
52
53        // /sys/class/tty/
54        let tty_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
55        class_dir.add_child("tty", tty_dir)?;
56
57        // /sys/class/input/
58        let input_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
59        class_dir.add_child("input", input_dir)?;
60
61        // /sys/class/rtc/
62        let rtc_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
63        class_dir.add_child("rtc", rtc_dir)?;
64
65        // /sys/kernel/
66        let kernel_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
67        root.add_child("kernel", kernel_dir)?;
68
69        // /sys/devices/
70        let devices_dir = SysfsInode::new_directory(FileMode::from_bits_truncate(0o040000 | 0o555));
71        root.add_child("devices", devices_dir)?;
72
73        // /sys/block/ -> class/block/ (向后兼容符号链接)
74        let block_symlink = SysfsInode::new_symlink("class/block".to_string());
75        root.add_child("block", block_symlink)?;
76
77        Ok(())
78    }
79
80    fn build_device_trees(&self) -> Result<(), FsError> {
81        use super::builders;
82
83        // 1. 先在 /sys/devices/ 创建真实设备树
84        builders::devices::build_platform_devices(&self.root_inode)?;
85
86        // 2. 再在 /sys/class/ 创建符号链接
87        builders::block::build_block_devices(&self.root_inode)?;
88        builders::net::build_net_devices(&self.root_inode)?;
89        builders::tty::build_tty_devices(&self.root_inode)?;
90        builders::input::build_input_devices(&self.root_inode)?;
91        builders::rtc::build_rtc_devices(&self.root_inode)?;
92
93        // 3. 构建内核信息树
94        builders::kernel::build_kernel_info(&self.root_inode)?;
95
96        Ok(())
97    }
98}
99
100impl FileSystem for SysFS {
101    fn fs_type(&self) -> &'static str {
102        "sysfs"
103    }
104
105    fn root_inode(&self) -> Arc<dyn Inode> {
106        self.root_inode.clone()
107    }
108
109    fn sync(&self) -> Result<(), FsError> {
110        // sysfs 是纯虚拟文件系统,无需同步
111        Ok(())
112    }
113
114    fn statfs(&self) -> Result<StatFs, FsError> {
115        Ok(StatFs {
116            block_size: 4096,
117            total_blocks: 0,
118            free_blocks: 0,
119            available_blocks: 0,
120            total_inodes: 0,
121            free_inodes: 0,
122            fsid: 0,
123            max_filename_len: 255,
124        })
125    }
126}
os/fs/sysfs/sysfs.rs

os/fs/sysfs/
sysfs.rs
