Add ramfs

src/services/libs/jinux-std/src/fs/mod.rs

@@ -6,6 +6,7 @@ pub mod file_table;
 pub mod inode_handle;
 pub mod ioctl;
 pub mod poll;
+pub mod ramfs;
 pub mod stat;
 pub mod stdio;
 pub mod utils;

src/services/libs/jinux-std/src/fs/ramfs/fs.rs

@@ -0,0 +1,568 @@
+use crate::prelude::*;
+use alloc::str;
+use alloc::string::String;
+use core::any::Any;
+use core::sync::atomic::{AtomicUsize, Ordering};
+use jinux_frame::vm::VmFrame;
+use spin::{RwLock, RwLockWriteGuard};
+
+use super::*;
+use crate::fs::ioctl::IoctlCmd;
+use crate::fs::utils::{
+    DirentWriterContext, FileSystem, Inode, InodeMode, InodeType, Metadata, SuperBlock,
+};
+
+pub struct RamFS {
+    metadata: RwLock<SuperBlock>,
+    root: Arc<RamInode>,
+    inode_allocator: AtomicUsize,
+}
+
+impl RamFS {
+    pub fn new() -> Arc<Self> {
+        let root = Arc::new(RamInode(RwLock::new(Inode_::new_dir(
+            ROOT_INO,
+            InodeMode::from_bits_truncate(0o755),
+        ))));
+        let ramfs = Arc::new(Self {
+            metadata: RwLock::new(SuperBlock::new(RAMFS_MAGIC, BLOCK_SIZE, NAME_MAX)),
+            root,
+            inode_allocator: AtomicUsize::new(ROOT_INO + 1),
+        });
+        let mut root = ramfs.root.0.write();
+        root.inner
+            .as_direntry_mut()
+            .unwrap()
+            .init(Arc::downgrade(&ramfs.root), Arc::downgrade(&ramfs.root));
+        root.this = Arc::downgrade(&ramfs.root);
+        root.fs = Arc::downgrade(&ramfs);
+        drop(root);
+        ramfs
+    }
+
+    fn alloc_id(&self) -> usize {
+        let next_id = self.inode_allocator.fetch_add(1, Ordering::SeqCst);
+        self.metadata.write().files += 1;
+        next_id
+    }
+}
+
+impl FileSystem for RamFS {
+    fn sync(&self) -> Result<()> {
+        // do nothing
+        Ok(())
+    }
+
+    fn root_inode(&self) -> Arc<dyn Inode> {
+        self.root.clone()
+    }
+
+    fn sb(&self) -> SuperBlock {
+        self.metadata.read().clone()
+    }
+}
+
+struct RamInode(RwLock<Inode_>);
+
+struct Inode_ {
+    inner: Inner,
+    metadata: Metadata,
+    this: Weak<RamInode>,
+    fs: Weak<RamFS>,
+}
+
+impl Inode_ {
+    pub fn new_dir(ino: usize, mode: InodeMode) -> Self {
+        Self {
+            inner: Inner::Dir(DirEntry::new()),
+            metadata: Metadata::new_dir(ino, mode),
+            this: Weak::default(),
+            fs: Weak::default(),
+        }
+    }
+
+    pub fn new_file(ino: usize, mode: InodeMode) -> Self {
+        Self {
+            inner: Inner::File,
+            metadata: Metadata::new_file(ino, mode),
+            this: Weak::default(),
+            fs: Weak::default(),
+        }
+    }
+
+    pub fn new_symlink(ino: usize, mode: InodeMode) -> Self {
+        Self {
+            inner: Inner::SymLink(Str256::from("")),
+            metadata: Metadata::new_synlink(ino, mode),
+            this: Weak::default(),
+            fs: Weak::default(),
+        }
+    }
+}
+
+enum Inner {
+    Dir(DirEntry),
+    File,
+    SymLink(Str256),
+}
+
+impl Inner {
+    fn as_direntry(&self) -> Option<&DirEntry> {
+        match self {
+            Inner::Dir(dir_entry) => Some(dir_entry),
+            _ => None,
+        }
+    }
+
+    fn as_direntry_mut(&mut self) -> Option<&mut DirEntry> {
+        match self {
+            Inner::Dir(dir_entry) => Some(dir_entry),
+            _ => None,
+        }
+    }
+
+    fn as_symlink(&self) -> Option<&str> {
+        match self {
+            Inner::SymLink(link) => Some(link.as_ref()),
+            _ => None,
+        }
+    }
+
+    fn as_symlink_mut(&mut self) -> Option<&mut Str256> {
+        match self {
+            Inner::SymLink(link) => Some(link),
+            _ => None,
+        }
+    }
+}
+
+struct DirEntry {
+    children: LinkedList<(Str256, Arc<RamInode>)>,
+    this: Weak<RamInode>,
+    parent: Weak<RamInode>,
+}
+
+macro_rules! write_inode_entry {
+    ($ctx:expr, $name:expr, $inode:expr, $total_written:expr) => {
+        let ctx = $ctx;
+        let name = $name;
+        let inode = $inode;
+        let total_written = $total_written;
+
+        match ctx.write_entry(
+            name.as_ref(),
+            inode.metadata().ino as u64,
+            inode.metadata().type_,
+        ) {
+            Ok(written_len) => {
+                *total_written += written_len;
+            }
+            Err(e) => {
+                if *total_written == 0 {
+                    return Err(e);
+                } else {
+                    return Ok(*total_written);
+                }
+            }
+        }
+    };
+}
+
+impl DirEntry {
+    fn new() -> Self {
+        Self {
+            children: LinkedList::new(),
+            this: Weak::default(),
+            parent: Weak::default(),
+        }
+    }
+
+    fn init(&mut self, this: Weak<RamInode>, parent: Weak<RamInode>) {
+        self.this = this;
+        self.set_parent(parent);
+    }
+
+    fn set_parent(&mut self, parent: Weak<RamInode>) {
+        self.parent = parent;
+    }
+
+    fn contains_entry(&self, name: &str) -> bool {
+        if name == "." || name == ".." {
+            true
+        } else {
+            self.children
+                .iter()
+                .find(|(child, _)| child == &Str256::from(name))
+                .is_some()
+        }
+    }
+
+    fn get_entry(&self, name: &str) -> Option<(usize, Arc<RamInode>)> {
+        if name == "." {
+            Some((0, self.this.upgrade().unwrap()))
+        } else if name == ".." {
+            Some((1, self.parent.upgrade().unwrap()))
+        } else {
+            self.children
+                .iter()
+                .enumerate()
+                .find(|(idx, (child, inode))| child == &Str256::from(name))
+                .map(|(idx, (_, inode))| (idx + 2, inode.clone()))
+        }
+    }
+
+    fn append_entry(&mut self, name: &str, inode: Arc<RamInode>) {
+        self.children.push_back((Str256::from(name), inode))
+    }
+
+    fn remove_entry(&mut self, idx: usize) -> (Str256, Arc<RamInode>) {
+        assert!(idx >= 2);
+        self.children.remove(idx - 2)
+    }
+
+    fn modify_entry(&mut self, idx: usize, new_name: &str) {
+        assert!(idx >= 2);
+        let (name, _) = self.children.iter_mut().nth(idx - 2).unwrap();
+        *name = Str256::from(new_name);
+    }
+
+    fn iterate_entries(&self, mut ctx: &mut DirentWriterContext) -> Result<usize> {
+        let mut total_written_len = 0;
+        let idx = ctx.pos();
+        // Write the two special entries
+        if idx == 0 {
+            let this_inode = self.this.upgrade().unwrap();
+            write_inode_entry!(&mut ctx, ".", &this_inode, &mut total_written_len);
+        }
+        if idx <= 1 {
+            let parent_inode = self.parent.upgrade().unwrap();
+            write_inode_entry!(&mut ctx, "..", &parent_inode, &mut total_written_len);
+        }
+        // Write the normal entries
+        let skipped_children = if idx < 2 { 0 } else { idx - 2 };
+        for (name, child) in self.children.iter().skip(skipped_children) {
+            write_inode_entry!(&mut ctx, name, child, &mut total_written_len);
+        }
+        Ok(total_written_len)
+    }
+
+    fn is_empty_children(&self) -> bool {
+        self.children.is_empty()
+    }
+}
+
+#[repr(C)]
+#[derive(Clone, PartialEq, PartialOrd, Eq, Ord)]
+pub struct Str256([u8; 256]);
+
+impl AsRef<str> for Str256 {
+    fn as_ref(&self) -> &str {
+        let len = self.0.iter().enumerate().find(|(_, &b)| b == 0).unwrap().0;
+        str::from_utf8(&self.0[0..len]).unwrap()
+    }
+}
+
+impl<'a> From<&'a str> for Str256 {
+    fn from(s: &'a str) -> Self {
+        let mut inner = [0u8; 256];
+        let len = if s.len() > NAME_MAX {
+            NAME_MAX
+        } else {
+            s.len()
+        };
+        inner[0..len].copy_from_slice(&s.as_bytes()[0..len]);
+        Str256(inner)
+    }
+}
+
+impl core::fmt::Debug for Str256 {
+    fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
+        write!(f, "{}", self.as_ref())
+    }
+}
+
+impl Inode for RamInode {
+    fn read_page(&self, _idx: usize, _frame: &VmFrame) -> Result<()> {
+        // do nothing
+        Ok(())
+    }
+
+    fn write_page(&self, _idx: usize, _frame: &VmFrame) -> Result<()> {
+        // do nothing
+        Ok(())
+    }
+
+    fn read_at(&self, offset: usize, buf: &mut [u8]) -> Result<usize> {
+        return_errno_with_message!(Errno::EOPNOTSUPP, "direct read is not supported");
+    }
+
+    fn write_at(&self, offset: usize, buf: &[u8]) -> Result<usize> {
+        return_errno_with_message!(Errno::EOPNOTSUPP, "direct read is not supported");
+    }
+
+    fn resize(&self, new_size: usize) -> Result<()> {
+        if self.0.read().metadata.type_ != InodeType::File {
+            return_errno_with_message!(Errno::EISDIR, "self is not file");
+        }
+        self.0.write().metadata.size = new_size;
+        Ok(())
+    }
+
+    fn mknod(&self, name: &str, type_: InodeType, mode: InodeMode) -> Result<Arc<dyn Inode>> {
+        if self.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "self is not dir");
+        }
+        let mut self_inode = self.0.write();
+        if self_inode.inner.as_direntry().unwrap().contains_entry(name) {
+            return_errno_with_message!(Errno::EEXIST, "entry exists");
+        }
+        let new_inode = match type_ {
+            InodeType::File => {
+                let file_inode = Arc::new(RamInode(RwLock::new(Inode_::new_file(
+                    self_inode.fs.upgrade().unwrap().alloc_id(),
+                    mode,
+                ))));
+                file_inode.0.write().fs = self_inode.fs.clone();
+                file_inode
+            }
+            InodeType::Dir => {
+                let dir_inode = Arc::new(RamInode(RwLock::new(Inode_::new_dir(
+                    self_inode.fs.upgrade().unwrap().alloc_id(),
+                    mode,
+                ))));
+                dir_inode.0.write().fs = self_inode.fs.clone();
+                dir_inode.0.write().inner.as_direntry_mut().unwrap().init(
+                    Arc::downgrade(&dir_inode),
+                    self_inode.inner.as_direntry().unwrap().this.clone(),
+                );
+                dir_inode
+            }
+            InodeType::SymLink => {
+                let sym_inode = Arc::new(RamInode(RwLock::new(Inode_::new_symlink(
+                    self_inode.fs.upgrade().unwrap().alloc_id(),
+                    mode,
+                ))));
+                sym_inode.0.write().fs = self_inode.fs.clone();
+                sym_inode
+            }
+            _ => {
+                panic!("unsupported inode type");
+            }
+        };
+        new_inode.0.write().this = Arc::downgrade(&new_inode);
+        self_inode
+            .inner
+            .as_direntry_mut()
+            .unwrap()
+            .append_entry(name, new_inode.clone());
+        Ok(new_inode)
+    }
+
+    fn readdir(&self, ctx: &mut DirentWriterContext) -> Result<usize> {
+        if self.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "self is not dir");
+        }
+        let self_inode = self.0.read();
+        let total_written_len = self_inode
+            .inner
+            .as_direntry()
+            .unwrap()
+            .iterate_entries(ctx)?;
+        Ok(total_written_len)
+    }
+
+    fn link(&self, old: &Arc<dyn Inode>, name: &str) -> Result<()> {
+        if self.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "self is not dir");
+        }
+        let old = old
+            .downcast_ref::<RamInode>()
+            .ok_or(Error::new(Errno::EXDEV))?;
+        if old.0.read().metadata.type_ == InodeType::Dir {
+            return_errno_with_message!(Errno::EPERM, "old is a dir");
+        }
+        let mut self_inode = self.0.write();
+        if self_inode.inner.as_direntry().unwrap().contains_entry(name) {
+            return_errno_with_message!(Errno::EEXIST, "entry exist");
+        }
+
+        self_inode
+            .inner
+            .as_direntry_mut()
+            .unwrap()
+            .append_entry(name, old.0.read().this.upgrade().unwrap());
+        Ok(())
+    }
+
+    fn unlink(&self, name: &str) -> Result<()> {
+        if self.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "self is not dir");
+        }
+        if name == "." || name == ".." {
+            return_errno_with_message!(Errno::EISDIR, "unlink . or ..");
+        }
+        let mut self_inode = self.0.write();
+        let self_dir = self_inode.inner.as_direntry_mut().unwrap();
+        let (idx, other) = self_dir.get_entry(name).ok_or(Error::new(Errno::ENOENT))?;
+        let other_inode = other.0.read();
+        if other_inode.metadata.type_ == InodeType::Dir
+            && !other_inode.inner.as_direntry().unwrap().is_empty_children()
+        {
+            return_errno_with_message!(Errno::ENOTEMPTY, "dir not empty");
+        }
+        self_dir.remove_entry(idx);
+        Ok(())
+    }
+
+    fn lookup(&self, name: &str) -> Result<Arc<dyn Inode>> {
+        if self.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "self is not dir");
+        }
+
+        let (_, inode) = self
+            .0
+            .read()
+            .inner
+            .as_direntry()
+            .unwrap()
+            .get_entry(name)
+            .ok_or(Error::new(Errno::ENOENT))?;
+        Ok(inode as _)
+    }
+
+    fn rename(&self, old_name: &str, target: &Arc<dyn Inode>, new_name: &str) -> Result<()> {
+        if self.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "self is not dir");
+        }
+        let target = target
+            .downcast_ref::<RamInode>()
+            .ok_or(Error::new(Errno::EXDEV))?;
+        if target.0.read().metadata.type_ != InodeType::Dir {
+            return_errno_with_message!(Errno::ENOTDIR, "target is not dir");
+        }
+        if old_name == "." || old_name == ".." {
+            return_errno_with_message!(Errno::EISDIR, "old_name is . or ..");
+        }
+        if new_name == "." || new_name == ".." {
+            return_errno_with_message!(Errno::EISDIR, "new_name is . or ..");
+        }
+        let src_inode = self.lookup(old_name)?;
+        if src_inode.metadata().ino == target.metadata().ino {
+            return_errno_with_message!(Errno::EINVAL, "target is a descendant of old");
+        }
+        if let Ok(dst_inode) = target.lookup(new_name) {
+            if src_inode.metadata().ino == dst_inode.metadata().ino {
+                return Ok(());
+            }
+            match (src_inode.metadata().type_, dst_inode.metadata().type_) {
+                (InodeType::Dir, InodeType::Dir) => {
+                    let dst_inode = dst_inode.downcast_ref::<RamInode>().unwrap();
+                    if !dst_inode
+                        .0
+                        .read()
+                        .inner
+                        .as_direntry()
+                        .unwrap()
+                        .is_empty_children()
+                    {
+                        return_errno_with_message!(Errno::ENOTEMPTY, "dir not empty");
+                    }
+                }
+                (InodeType::Dir, _) => {
+                    return_errno_with_message!(Errno::ENOTDIR, "old is not dir");
+                }
+                (_, InodeType::Dir) => {
+                    return_errno_with_message!(Errno::EISDIR, "new is dir");
+                }
+                _ => {}
+            }
+        }
+        if self.metadata().ino == target.metadata().ino {
+            let mut self_inode = self.0.write();
+            let self_dir = self_inode.inner.as_direntry_mut().unwrap();
+            let (idx, _) = self_dir
+                .get_entry(old_name)
+                .ok_or(Error::new(Errno::ENOENT))?;
+            self_dir.modify_entry(idx, new_name);
+        } else {
+            let (mut self_inode, mut target_inode) = write_lock_two_inodes(self, target);
+            let self_dir = self_inode.inner.as_direntry_mut().unwrap();
+            let (idx, src_inode) = self_dir
+                .get_entry(old_name)
+                .ok_or(Error::new(Errno::ENOENT))?;
+            self_dir.remove_entry(idx);
+            target_inode
+                .inner
+                .as_direntry_mut()
+                .unwrap()
+                .append_entry(new_name, src_inode.clone());
+            drop(self_inode);
+            drop(target_inode);
+            if src_inode.metadata().type_ == InodeType::Dir {
+                src_inode
+                    .0
+                    .write()
+                    .inner
+                    .as_direntry_mut()
+                    .unwrap()
+                    .set_parent(target.0.read().this.clone());
+            }
+        }
+        Ok(())
+    }
+
+    fn read_link(&self) -> Result<String> {
+        if self.0.read().metadata.type_ != InodeType::SymLink {
+            return_errno_with_message!(Errno::EINVAL, "self is not symlink");
+        }
+        let self_inode = self.0.read();
+        let link = self_inode.inner.as_symlink().unwrap();
+        Ok(String::from(link))
+    }
+
+    fn write_link(&self, target: &str) -> Result<()> {
+        if self.0.read().metadata.type_ != InodeType::SymLink {
+            return_errno_with_message!(Errno::EINVAL, "self is not symlink");
+        }
+        let mut self_inode = self.0.write();
+        let link = self_inode.inner.as_symlink_mut().unwrap();
+        *link = Str256::from(target);
+        Ok(())
+    }
+
+    fn metadata(&self) -> Metadata {
+        self.0.read().metadata.clone()
+    }
+
+    fn sync(&self) -> Result<()> {
+        // do nothing
+        Ok(())
+    }
+
+    fn fs(&self) -> Arc<dyn FileSystem> {
+        Weak::upgrade(&self.0.read().fs).unwrap()
+    }
+
+    fn ioctl(&self, cmd: &IoctlCmd) -> Result<()> {
+        return_errno!(Errno::ENOSYS);
+    }
+
+    fn as_any_ref(&self) -> &dyn Any {
+        self
+    }
+}
+
+fn write_lock_two_inodes<'a>(
+    this: &'a RamInode,
+    other: &'a RamInode,
+) -> (RwLockWriteGuard<'a, Inode_>, RwLockWriteGuard<'a, Inode_>) {
+    if this.0.read().metadata.ino < other.0.read().metadata.ino {
+        let this = this.0.write();
+        let other = other.0.write();
+        (this, other)
+    } else {
+        let other = other.0.write();
+        let this = this.0.write();
+        (this, other)
+    }
+}

src/services/libs/jinux-std/src/fs/ramfs/mod.rs

@@ -0,0 +1,10 @@
+//! Ramfs based on PageCache
+
+pub use fs::RamFS;
+
+mod fs;
+
+const RAMFS_MAGIC: usize = 0x0102_1994;
+const BLOCK_SIZE: usize = 4096;
+const NAME_MAX: usize = 255;
+const ROOT_INO: usize = 1;

src/services/libs/jinux-std/src/fs/utils/fs.rs

@@ -18,6 +18,24 @@ pub struct SuperBlock {
     pub flags: usize,
 }
 
+impl SuperBlock {
+    pub fn new(magic: usize, block_size: usize, name_len: usize) -> Self {
+        Self {
+            magic,
+            bsize: block_size,
+            blocks: 0,
+            bfree: 0,
+            bavail: 0,
+            files: 0,
+            ffree: 0,
+            fsid: 0,
+            namelen: 255,
+            frsize: block_size,
+            flags: 0,
+        }
+    }
+}
+
 pub trait FileSystem: Sync + Send {
     fn sync(&self) -> Result<()>;
 

src/services/libs/jinux-std/src/fs/utils/inode.rs

@@ -91,6 +91,65 @@ pub struct Metadata {
     pub rdev: usize,
 }
 
+impl Metadata {
+    pub fn new_dir(ino: usize, mode: InodeMode) -> Self {
+        Self {
+            dev: 0,
+            ino,
+            size: 2,
+            blk_size: 0,
+            blocks: 0,
+            atime: Timespec { sec: 0, nsec: 0 },
+            mtime: Timespec { sec: 0, nsec: 0 },
+            ctime: Timespec { sec: 0, nsec: 0 },
+            type_: InodeType::Dir,
+            mode,
+            nlinks: 2,
+            uid: 0,
+            gid: 0,
+            rdev: 0,
+        }
+    }
+
+    pub fn new_file(ino: usize, mode: InodeMode) -> Self {
+        Self {
+            dev: 0,
+            ino,
+            size: 0,
+            blk_size: 0,
+            blocks: 0,
+            atime: Timespec { sec: 0, nsec: 0 },
+            mtime: Timespec { sec: 0, nsec: 0 },
+            ctime: Timespec { sec: 0, nsec: 0 },
+            type_: InodeType::File,
+            mode,
+            nlinks: 1,
+            uid: 0,
+            gid: 0,
+            rdev: 0,
+        }
+    }
+
+    pub fn new_synlink(ino: usize, mode: InodeMode) -> Self {
+        Self {
+            dev: 0,
+            ino,
+            size: 0,
+            blk_size: 0,
+            blocks: 0,
+            atime: Timespec { sec: 0, nsec: 0 },
+            mtime: Timespec { sec: 0, nsec: 0 },
+            ctime: Timespec { sec: 0, nsec: 0 },
+            type_: InodeType::SymLink,
+            mode,
+            nlinks: 1,
+            uid: 0,
+            gid: 0,
+            rdev: 0,
+        }
+    }
+}
+
 #[derive(Default, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
 pub struct Timespec {
     pub sec: i64,

src/services/libs/jinux-std/src/lib.rs

@@ -15,6 +15,7 @@
 // We should find a proper method to replace this feature with min_specialization, which is a sound feature.
 #![feature(specialization)]
 #![feature(fn_traits)]
+#![feature(linked_list_remove)]
 
 use crate::{
     prelude::*,