1 use crate::filesystem::vfs::file::FileMode; 2 use crate::filesystem::vfs::make_rawdev; 3 use crate::filesystem::vfs::{ 4 core::generate_inode_id, FilePrivateData, FileSystem, FileType, IndexNode, Metadata, PollStatus, 5 }; 6 use crate::{libs::spinlock::SpinLock, syscall::SystemError, time::TimeSpec}; 7 use alloc::{ 8 string::String, 9 sync::{Arc, Weak}, 10 vec::Vec, 11 }; 12 // use uuid::{uuid, Uuid}; 13 use super::{DevFS, DeviceINode}; 14 15 #[derive(Debug)] 16 pub struct NullInode { 17 /// uuid 暂时不知道有什么用（x 18 // uuid: Uuid, 19 /// 指向自身的弱引用 20 self_ref: Weak<LockedNullInode>, 21 /// 指向inode所在的文件系统对象的指针 22 fs: Weak<DevFS>, 23 /// INode 元数据 24 metadata: Metadata, 25 } 26 27 #[derive(Debug)] 28 pub struct LockedNullInode(SpinLock<NullInode>); 29 30 impl LockedNullInode { 31 pub fn new() -> Arc<Self> { 32 let inode = NullInode { 33 // uuid: Uuid::new_v5(), 34 self_ref: Weak::default(), 35 fs: Weak::default(), 36 metadata: Metadata { 37 dev_id: 1, 38 inode_id: generate_inode_id(), 39 size: 0, 40 blk_size: 0, 41 blocks: 0, 42 atime: TimeSpec::default(), 43 mtime: TimeSpec::default(), 44 ctime: TimeSpec::default(), 45 file_type: FileType::CharDevice, // 文件夹，block设备，char设备 46 mode: 0o666, 47 nlinks: 1, 48 uid: 0, 49 gid: 0, 50 raw_dev: make_rawdev(1, 3), // 这里用来作为device number 51 }, 52 }; 53 54 let result = Arc::new(LockedNullInode(SpinLock::new(inode))); 55 result.0.lock().self_ref = Arc::downgrade(&result); 56 57 return result; 58 } 59 } 60 61 impl DeviceINode for LockedNullInode { 62 fn set_fs(&self, fs: Weak<DevFS>) { 63 self.0.lock().fs = fs; 64 } 65 } 66 67 impl IndexNode for LockedNullInode { 68 fn as_any_ref(&self) -> &dyn core::any::Any { 69 self 70 } 71 72 fn open(&self, _data: &mut FilePrivateData, _mode: &FileMode) -> Result<(), SystemError> { 73 Err(SystemError::EOPNOTSUPP_OR_ENOTSUP) 74 } 75 76 fn close(&self, _data: &mut FilePrivateData) -> Result<(), SystemError> { 77 Err(SystemError::EOPNOTSUPP_OR_ENOTSUP) 78 } 79 80 fn metadata(&self) -> Result<Metadata, SystemError> { 81 return Ok(self.0.lock().metadata.clone()); 82 } 83 84 fn fs(&self) -> Arc<dyn FileSystem> { 85 return self.0.lock().fs.upgrade().unwrap(); 86 } 87 88 fn list(&self) -> Result<Vec<String>, SystemError> { 89 Err(SystemError::EOPNOTSUPP_OR_ENOTSUP) 90 } 91 92 fn set_metadata(&self, metadata: &Metadata) -> Result<(), SystemError> { 93 let mut inode = self.0.lock(); 94 inode.metadata.atime = metadata.atime; 95 inode.metadata.mtime = metadata.mtime; 96 inode.metadata.ctime = metadata.ctime; 97 inode.metadata.mode = metadata.mode; 98 inode.metadata.uid = metadata.uid; 99 inode.metadata.gid = metadata.gid; 100 101 return Ok(()); 102 } 103 104 fn poll(&self) -> Result<PollStatus, SystemError> { 105 return Ok(PollStatus::READ | PollStatus::WRITE); 106 } 107 108 /// 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 109 fn read_at( 110 &self, 111 _offset: usize, 112 len: usize, 113 buf: &mut [u8], 114 _data: &mut FilePrivateData, 115 ) -> Result<usize, SystemError> { 116 if buf.len() < len { 117 return Err(SystemError::EINVAL); 118 } 119 120 for i in 0..len { 121 buf[i] = 0; 122 } 123 124 return Ok(len); 125 } 126 127 /// 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 128 fn write_at( 129 &self, 130 _offset: usize, 131 len: usize, 132 buf: &[u8], 133 _data: &mut FilePrivateData, 134 ) -> Result<usize, SystemError> { 135 if buf.len() < len { 136 return Err(SystemError::EINVAL); 137 } 138 139 Ok(len) 140 } 141 } 142