1 use crate::filesystem::vfs::file::FileMode; 2 use crate::filesystem::vfs::make_rawdev; 3 use crate::filesystem::vfs::syscall::ModeType; 4 use crate::filesystem::vfs::{ 5 core::generate_inode_id, FilePrivateData, FileSystem, FileType, IndexNode, Metadata, 6 }; 7 use crate::{libs::spinlock::SpinLock, syscall::SystemError, time::TimeSpec}; 8 use alloc::{ 9 string::String, 10 sync::{Arc, Weak}, 11 vec::Vec, 12 }; 13 // use uuid::{uuid, Uuid}; 14 use super::{DevFS, DeviceINode}; 15 16 #[derive(Debug)] 17 pub struct NullInode { 18 /// uuid 暂时不知道有什么用（x 19 // uuid: Uuid, 20 /// 指向自身的弱引用 21 self_ref: Weak<LockedNullInode>, 22 /// 指向inode所在的文件系统对象的指针 23 fs: Weak<DevFS>, 24 /// INode 元数据 25 metadata: Metadata, 26 } 27 28 #[derive(Debug)] 29 pub struct LockedNullInode(SpinLock<NullInode>); 30 31 impl LockedNullInode { 32 pub fn new() -> Arc<Self> { 33 let inode = NullInode { 34 // uuid: Uuid::new_v5(), 35 self_ref: Weak::default(), 36 fs: Weak::default(), 37 metadata: Metadata { 38 dev_id: 1, 39 inode_id: generate_inode_id(), 40 size: 0, 41 blk_size: 0, 42 blocks: 0, 43 atime: TimeSpec::default(), 44 mtime: TimeSpec::default(), 45 ctime: TimeSpec::default(), 46 file_type: FileType::CharDevice, // 文件夹，block设备，char设备 47 mode: ModeType::from_bits_truncate(0o666), 48 nlinks: 1, 49 uid: 0, 50 gid: 0, 51 raw_dev: make_rawdev(1, 3), // 这里用来作为device number 52 }, 53 }; 54 55 let result = Arc::new(LockedNullInode(SpinLock::new(inode))); 56 result.0.lock().self_ref = Arc::downgrade(&result); 57 58 return result; 59 } 60 } 61 62 impl DeviceINode for LockedNullInode { 63 fn set_fs(&self, fs: Weak<DevFS>) { 64 self.0.lock().fs = fs; 65 } 66 } 67 68 impl IndexNode for LockedNullInode { 69 fn as_any_ref(&self) -> &dyn core::any::Any { 70 self 71 } 72 73 fn open(&self, _data: &mut FilePrivateData, _mode: &FileMode) -> Result<(), SystemError> { 74 return Ok(()); 75 } 76 77 fn close(&self, _data: &mut FilePrivateData) -> Result<(), SystemError> { 78 return Ok(()); 79 } 80 81 fn metadata(&self) -> Result<Metadata, SystemError> { 82 return Ok(self.0.lock().metadata.clone()); 83 } 84 85 fn fs(&self) -> Arc<dyn FileSystem> { 86 return self.0.lock().fs.upgrade().unwrap(); 87 } 88 89 fn list(&self) -> Result<Vec<String>, SystemError> { 90 Err(SystemError::EOPNOTSUPP_OR_ENOTSUP) 91 } 92 93 fn set_metadata(&self, metadata: &Metadata) -> Result<(), SystemError> { 94 let mut inode = self.0.lock(); 95 inode.metadata.atime = metadata.atime; 96 inode.metadata.mtime = metadata.mtime; 97 inode.metadata.ctime = metadata.ctime; 98 inode.metadata.mode = metadata.mode; 99 inode.metadata.uid = metadata.uid; 100 inode.metadata.gid = metadata.gid; 101 102 return Ok(()); 103 } 104 105 /// 读设备 - 应该调用设备的函数读写，而不是通过文件系统读写 106 fn read_at( 107 &self, 108 _offset: usize, 109 _len: usize, 110 _buf: &mut [u8], 111 _data: &mut FilePrivateData, 112 ) -> Result<usize, SystemError> { 113 return Ok(0); 114 } 115 116 /// 写设备 - 应该调用设备的函数读写，而不是通过文件系统读写 117 fn write_at( 118 &self, 119 _offset: usize, 120 len: usize, 121 buf: &[u8], 122 _data: &mut FilePrivateData, 123 ) -> Result<usize, SystemError> { 124 if buf.len() < len { 125 return Err(SystemError::EINVAL); 126 } 127 128 Ok(len) 129 } 130 } 131