diff options
Diffstat (limited to 'tvix/store/src/fs')
| -rw-r--r-- | tvix/store/src/fs/file_attr.rs | 52 | ||||
| -rw-r--r-- | tvix/store/src/fs/fuse.rs | 119 | ||||
| -rw-r--r-- | tvix/store/src/fs/inode_tracker.rs | 457 | ||||
| -rw-r--r-- | tvix/store/src/fs/inodes.rs | 70 | ||||
| -rw-r--r-- | tvix/store/src/fs/mod.rs | 690 | ||||
| -rw-r--r-- | tvix/store/src/fs/tests.rs | 1171 | ||||
| -rw-r--r-- | tvix/store/src/fs/virtiofs.rs | 237 |
7 files changed, 2796 insertions, 0 deletions
diff --git a/tvix/store/src/fs/file_attr.rs b/tvix/store/src/fs/file_attr.rs new file mode 100644 index 000000000000..562cd9f19002 --- /dev/null +++ b/tvix/store/src/fs/file_attr.rs @@ -0,0 +1,52 @@ +use super::inodes::{DirectoryInodeData, InodeData}; +use fuse_backend_rs::abi::fuse_abi::Attr; + +/// The [Attr] describing the root +pub const ROOT_FILE_ATTR: Attr = Attr { + ino: fuse_backend_rs::api::filesystem::ROOT_ID, + size: 0, + blksize: 1024, + blocks: 0, + mode: libc::S_IFDIR as u32 | 0o555, + atime: 0, + mtime: 0, + ctime: 0, + atimensec: 0, + mtimensec: 0, + ctimensec: 0, + nlink: 0, + uid: 0, + gid: 0, + rdev: 0, + flags: 0, + #[cfg(target_os = "macos")] + crtime: 0, + #[cfg(target_os = "macos")] + crtimensec: 0, + #[cfg(target_os = "macos")] + padding: 0, +}; + +/// for given &Node and inode, construct an [Attr] +pub fn gen_file_attr(inode_data: &InodeData, inode: u64) -> Attr { + Attr { + ino: inode, + // FUTUREWORK: play with this numbers, as it affects read sizes for client applications. + blocks: 1024, + size: match inode_data { + InodeData::Regular(_, size, _) => *size as u64, + InodeData::Symlink(target) => target.len() as u64, + InodeData::Directory(DirectoryInodeData::Sparse(_, size)) => *size as u64, + InodeData::Directory(DirectoryInodeData::Populated(_, ref children)) => { + children.len() as u64 + } + }, + mode: match inode_data { + InodeData::Regular(_, _, false) => libc::S_IFREG as u32 | 0o444, // no-executable files + InodeData::Regular(_, _, true) => libc::S_IFREG as u32 | 0o555, // executable files + InodeData::Symlink(_) => libc::S_IFLNK as u32 | 0o444, + InodeData::Directory(_) => libc::S_IFDIR as u32 | 0o555, + }, + ..Default::default() + } +} diff --git a/tvix/store/src/fs/fuse.rs b/tvix/store/src/fs/fuse.rs new file mode 100644 index 000000000000..d2a734882196 --- /dev/null +++ b/tvix/store/src/fs/fuse.rs @@ -0,0 +1,119 @@ +use std::{io, path::Path, sync::Arc, thread}; + +use fuse_backend_rs::{api::filesystem::FileSystem, transport::FuseSession}; +use tracing::error; + +struct FuseServer<FS> +where + FS: FileSystem + Sync + Send, +{ + server: Arc<fuse_backend_rs::api::server::Server<Arc<FS>>>, + channel: fuse_backend_rs::transport::FuseChannel, +} + +#[cfg(target_os = "macos")] +const BADFD: libc::c_int = libc::EBADF; +#[cfg(target_os = "linux")] +const BADFD: libc::c_int = libc::EBADFD; + +impl<FS> FuseServer<FS> +where + FS: FileSystem + Sync + Send, +{ + fn start(&mut self) -> io::Result<()> { + loop { + if let Some((reader, writer)) = self + .channel + .get_request() + .map_err(|_| io::Error::from_raw_os_error(libc::EINVAL))? + { + if let Err(e) = self + .server + .handle_message(reader, writer.into(), None, None) + { + match e { + // This indicates the session has been shut down. + fuse_backend_rs::Error::EncodeMessage(e) + if e.raw_os_error() == Some(BADFD) => + { + break; + } + error => { + error!(?error, "failed to handle fuse request"); + continue; + } + } + } + } else { + break; + } + } + Ok(()) + } +} + +pub struct FuseDaemon { + session: FuseSession, + threads: Vec<thread::JoinHandle<()>>, +} + +impl FuseDaemon { + pub fn new<FS, P>(fs: FS, mountpoint: P, threads: usize) -> Result<Self, io::Error> + where + FS: FileSystem + Sync + Send + 'static, + P: AsRef<Path>, + { + let server = Arc::new(fuse_backend_rs::api::server::Server::new(Arc::new(fs))); + + let mut session = FuseSession::new(mountpoint.as_ref(), "tvix-store", "", true) + .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?; + + #[cfg(target_os = "linux")] + session.set_allow_other(false); + session + .mount() + .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?; + let mut join_handles = Vec::with_capacity(threads); + for _ in 0..threads { + let mut server = FuseServer { + server: server.clone(), + channel: session + .new_channel() + .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?, + }; + let join_handle = thread::Builder::new() + .name("fuse_server".to_string()) + .spawn(move || { + let _ = server.start(); + })?; + join_handles.push(join_handle); + } + + Ok(FuseDaemon { + session, + threads: join_handles, + }) + } + + pub fn unmount(&mut self) -> Result<(), io::Error> { + self.session + .umount() + .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?; + + for thread in self.threads.drain(..) { + thread.join().map_err(|_| { + io::Error::new(io::ErrorKind::Other, "failed to join fuse server thread") + })?; + } + + Ok(()) + } +} + +impl Drop for FuseDaemon { + fn drop(&mut self) { + if let Err(error) = self.unmount() { + error!(?error, "failed to unmont fuse filesystem") + } + } +} diff --git a/tvix/store/src/fs/inode_tracker.rs b/tvix/store/src/fs/inode_tracker.rs new file mode 100644 index 000000000000..daf6b4ee79c2 --- /dev/null +++ b/tvix/store/src/fs/inode_tracker.rs @@ -0,0 +1,457 @@ +use std::{collections::HashMap, sync::Arc}; + +use super::inodes::{DirectoryInodeData, InodeData}; +use tvix_castore::proto as castorepb; +use tvix_castore::B3Digest; + +/// InodeTracker keeps track of inodes, stores data being these inodes and deals +/// with inode allocation. +pub struct InodeTracker { + data: HashMap<u64, Arc<InodeData>>, + + // lookup table for blobs by their B3Digest + blob_digest_to_inode: HashMap<B3Digest, u64>, + + // lookup table for symlinks by their target + symlink_target_to_inode: HashMap<bytes::Bytes, u64>, + + // lookup table for directories by their B3Digest. + // Note the corresponding directory may not be present in data yet. + directory_digest_to_inode: HashMap<B3Digest, u64>, + + // the next inode to allocate + next_inode: u64, +} + +impl Default for InodeTracker { + fn default() -> Self { + Self { + data: Default::default(), + + blob_digest_to_inode: Default::default(), + symlink_target_to_inode: Default::default(), + directory_digest_to_inode: Default::default(), + + next_inode: 2, + } + } +} + +impl InodeTracker { + // Retrieves data for a given inode, if it exists. + pub fn get(&self, ino: u64) -> Option<Arc<InodeData>> { + self.data.get(&ino).cloned() + } + + // Stores data and returns the inode for it. + // In case an inode has already been allocated for the same data, that inode + // is returned, otherwise a new one is allocated. + // In case data is a [InodeData::Directory], inodes for all items are looked + // up + pub fn put(&mut self, data: InodeData) -> u64 { + match data { + InodeData::Regular(ref digest, _, _) => { + match self.blob_digest_to_inode.get(digest) { + Some(found_ino) => { + // We already have it, return the inode. + *found_ino + } + None => self.insert_and_increment(data), + } + } + InodeData::Symlink(ref target) => { + match self.symlink_target_to_inode.get(target) { + Some(found_ino) => { + // We already have it, return the inode. + *found_ino + } + None => self.insert_and_increment(data), + } + } + InodeData::Directory(DirectoryInodeData::Sparse(ref digest, _size)) => { + // check the lookup table if the B3Digest is known. + match self.directory_digest_to_inode.get(digest) { + Some(found_ino) => { + // We already have it, return the inode. + *found_ino + } + None => { + // insert and return the inode + self.insert_and_increment(data) + } + } + } + // Inserting [DirectoryInodeData::Populated] usually replaces an + // existing [DirectoryInodeData::Sparse] one. + InodeData::Directory(DirectoryInodeData::Populated(ref digest, ref children)) => { + let dir_ino = self.directory_digest_to_inode.get(digest); + if let Some(dir_ino) = dir_ino { + let dir_ino = *dir_ino; + + // We know the data must exist, as we found it in [directory_digest_to_inode]. + let needs_update = match **self.data.get(&dir_ino).unwrap() { + InodeData::Regular(..) | InodeData::Symlink(_) => { + panic!("unexpected type at inode {}", dir_ino); + } + // already populated, nothing to do + InodeData::Directory(DirectoryInodeData::Populated(..)) => false, + // in case the actual data is sparse, replace it with the populated one. + // this allocates inodes for new children in the process. + InodeData::Directory(DirectoryInodeData::Sparse( + ref old_digest, + ref _old_size, + )) => { + // sanity checking to ensure we update the right node + debug_assert_eq!(old_digest, digest); + + true + } + }; + + if needs_update { + // populate inode fields in children + let children = self.allocate_inodes_for_children(children.to_vec()); + + // update sparse data with populated data + self.data.insert( + dir_ino, + Arc::new(InodeData::Directory(DirectoryInodeData::Populated( + digest.clone(), + children, + ))), + ); + } + + dir_ino + } else { + // populate inode fields in children + let children = self.allocate_inodes_for_children(children.to_vec()); + // insert and return InodeData + self.insert_and_increment(InodeData::Directory(DirectoryInodeData::Populated( + digest.clone(), + children, + ))) + } + } + } + } + + // Consume a list of children with zeroed inodes, and allocate (or fetch existing) inodes. + fn allocate_inodes_for_children( + &mut self, + children: Vec<(u64, castorepb::node::Node)>, + ) -> Vec<(u64, castorepb::node::Node)> { + // allocate new inodes for all children + let mut children_new: Vec<(u64, castorepb::node::Node)> = Vec::new(); + + for (child_ino, ref child_node) in children { + debug_assert_eq!(0, child_ino, "expected child inode to be 0"); + let child_ino = match child_node { + castorepb::node::Node::Directory(directory_node) => { + // Try putting the sparse data in. If we already have a + // populated version, it'll not update it. + self.put(directory_node.into()) + } + castorepb::node::Node::File(file_node) => self.put(file_node.into()), + castorepb::node::Node::Symlink(symlink_node) => self.put(symlink_node.into()), + }; + + children_new.push((child_ino, child_node.clone())) + } + children_new + } + + // Inserts the data and returns the inode it was stored at, while + // incrementing next_inode. + fn insert_and_increment(&mut self, data: InodeData) -> u64 { + let ino = self.next_inode; + // insert into lookup tables + match data { + InodeData::Regular(ref digest, _, _) => { + self.blob_digest_to_inode.insert(digest.clone(), ino); + } + InodeData::Symlink(ref target) => { + self.symlink_target_to_inode.insert(target.clone(), ino); + } + InodeData::Directory(DirectoryInodeData::Sparse(ref digest, _size)) => { + self.directory_digest_to_inode.insert(digest.clone(), ino); + } + // This is currently not used outside test fixtures. + // Usually a [DirectoryInodeData::Sparse] is inserted and later + // "upgraded" with more data. + // However, as a future optimization, a lookup for a PathInfo could trigger a + // [DirectoryService::get_recursive()] request that "forks into + // background" and prepopulates all Directories in a closure. + InodeData::Directory(DirectoryInodeData::Populated(ref digest, _)) => { + self.directory_digest_to_inode.insert(digest.clone(), ino); + } + } + // Insert data + self.data.insert(ino, Arc::new(data)); + + // increment inode counter and return old inode. + self.next_inode += 1; + ino + } +} + +#[cfg(test)] +mod tests { + use crate::fs::inodes::DirectoryInodeData; + use crate::tests::fixtures; + use tvix_castore::proto as castorepb; + + use super::InodeData; + use super::InodeTracker; + + /// Getting something non-existent should be none + #[test] + fn get_nonexistent() { + let inode_tracker = InodeTracker::default(); + assert!(inode_tracker.get(1).is_none()); + } + + /// Put of a regular file should allocate a uid, which should be the same when inserting again. + #[test] + fn put_regular() { + let mut inode_tracker = InodeTracker::default(); + let f = InodeData::Regular( + fixtures::BLOB_A_DIGEST.clone(), + fixtures::BLOB_A.len() as u32, + false, + ); + + // put it in + let ino = inode_tracker.put(f.clone()); + + // a get should return the right data + let data = inode_tracker.get(ino).expect("must be some"); + match *data { + InodeData::Regular(ref digest, _, _) => { + assert_eq!(&fixtures::BLOB_A_DIGEST.clone(), digest); + } + InodeData::Symlink(_) | InodeData::Directory(..) => panic!("wrong type"), + } + + // another put should return the same ino + assert_eq!(ino, inode_tracker.put(f)); + + // inserting another file should return a different ino + assert_ne!( + ino, + inode_tracker.put(InodeData::Regular( + fixtures::BLOB_B_DIGEST.clone(), + fixtures::BLOB_B.len() as u32, + false, + )) + ); + } + + // Put of a symlink should allocate a uid, which should be the same when inserting again + #[test] + fn put_symlink() { + let mut inode_tracker = InodeTracker::default(); + let f = InodeData::Symlink("target".into()); + + // put it in + let ino = inode_tracker.put(f.clone()); + + // a get should return the right data + let data = inode_tracker.get(ino).expect("must be some"); + match *data { + InodeData::Symlink(ref target) => { + assert_eq!(b"target".to_vec(), *target); + } + InodeData::Regular(..) | InodeData::Directory(..) => panic!("wrong type"), + } + + // another put should return the same ino + assert_eq!(ino, inode_tracker.put(f)); + + // inserting another file should return a different ino + assert_ne!(ino, inode_tracker.put(InodeData::Symlink("target2".into()))); + } + + // TODO: put sparse directory + + /// Put a directory into the inode tracker, which refers to a file not seen yet. + #[test] + fn put_directory_leaf() { + let mut inode_tracker = InodeTracker::default(); + + // this is a directory with a single item, a ".keep" file pointing to a 0 bytes blob. + let dir: InodeData = fixtures::DIRECTORY_WITH_KEEP.clone().into(); + + // put it in + let dir_ino = inode_tracker.put(dir); + + // a get should return the right data + let data = inode_tracker.get(dir_ino).expect("must be some"); + match *data { + InodeData::Directory(super::DirectoryInodeData::Sparse(..)) => { + panic!("wrong type"); + } + InodeData::Directory(super::DirectoryInodeData::Populated( + ref directory_digest, + ref children, + )) => { + // ensure the directory digest matches + assert_eq!(&fixtures::DIRECTORY_WITH_KEEP.digest(), directory_digest); + + // ensure the child is populated, with a different inode than + // the parent, and the data matches expectations. + assert_eq!(1, children.len()); + let (child_ino, child_node) = children.first().unwrap(); + assert_ne!(dir_ino, *child_ino); + assert_eq!( + &castorepb::node::Node::File( + fixtures::DIRECTORY_WITH_KEEP.files.first().unwrap().clone() + ), + child_node + ); + + // ensure looking up that inode directly returns the data + let child_data = inode_tracker.get(*child_ino).expect("must exist"); + match *child_data { + InodeData::Regular(ref digest, size, executable) => { + assert_eq!(&fixtures::EMPTY_BLOB_DIGEST.clone(), digest); + assert_eq!(0, size); + assert!(!executable); + } + InodeData::Symlink(_) | InodeData::Directory(..) => panic!("wrong type"), + } + } + InodeData::Symlink(_) | InodeData::Regular(..) => panic!("wrong type"), + } + } + + /// Put a directory into the inode tracker, referring to files, directories + /// and symlinks not seen yet. + #[test] + fn put_directory_complicated() { + let mut inode_tracker = InodeTracker::default(); + + // this is a directory with a single item, a ".keep" file pointing to a 0 bytes blob. + let dir_complicated: InodeData = fixtures::DIRECTORY_COMPLICATED.clone().into(); + + // put it in + let dir_complicated_ino = inode_tracker.put(dir_complicated); + + // a get should return the right data + let dir_data = inode_tracker + .get(dir_complicated_ino) + .expect("must be some"); + + let child_dir_ino = match *dir_data { + InodeData::Directory(DirectoryInodeData::Sparse(..)) => { + panic!("wrong type"); + } + InodeData::Directory(DirectoryInodeData::Populated( + ref directory_digest, + ref children, + )) => { + // assert the directory digest matches + assert_eq!(&fixtures::DIRECTORY_COMPLICATED.digest(), directory_digest); + + // ensure there's three children, all with different inodes + assert_eq!(3, children.len()); + let mut seen_inodes = Vec::from([dir_complicated_ino]); + + // check the first child (.keep) + { + let (child_ino, child_node) = &children[0]; + assert!(!seen_inodes.contains(child_ino)); + assert_eq!( + &castorepb::node::Node::File( + fixtures::DIRECTORY_COMPLICATED.files[0].clone() + ), + child_node + ); + seen_inodes.push(*child_ino); + } + + // check the second child (aa) + { + let (child_ino, child_node) = &children[1]; + assert!(!seen_inodes.contains(child_ino)); + assert_eq!( + &castorepb::node::Node::Symlink( + fixtures::DIRECTORY_COMPLICATED.symlinks[0].clone() + ), + child_node + ); + seen_inodes.push(*child_ino); + } + + // check the third child (keep) + { + let (child_ino, child_node) = &children[2]; + assert!(!seen_inodes.contains(child_ino)); + assert_eq!( + &castorepb::node::Node::Directory( + fixtures::DIRECTORY_COMPLICATED.directories[0].clone() + ), + child_node + ); + seen_inodes.push(*child_ino); + + // return the child_ino + *child_ino + } + } + InodeData::Regular(..) | InodeData::Symlink(_) => panic!("wrong type"), + }; + + // get of the inode for child_ino + let child_dir_data = inode_tracker.get(child_dir_ino).expect("must be some"); + // it should be a sparse InodeData::Directory with the right digest. + match *child_dir_data { + InodeData::Directory(DirectoryInodeData::Sparse( + ref child_dir_digest, + child_dir_size, + )) => { + assert_eq!(&fixtures::DIRECTORY_WITH_KEEP.digest(), child_dir_digest); + assert_eq!(fixtures::DIRECTORY_WITH_KEEP.size(), child_dir_size); + } + InodeData::Directory(DirectoryInodeData::Populated(..)) + | InodeData::Regular(..) + | InodeData::Symlink(_) => { + panic!("wrong type") + } + } + + // put DIRECTORY_WITH_KEEP, which should return the same ino as [child_dir_ino], + // but update the sparse object to a populated one at the same time. + let child_dir_ino2 = inode_tracker.put(fixtures::DIRECTORY_WITH_KEEP.clone().into()); + assert_eq!(child_dir_ino, child_dir_ino2); + + // get the data + match *inode_tracker.get(child_dir_ino).expect("must be some") { + // it should be a populated InodeData::Directory with the right digest! + InodeData::Directory(DirectoryInodeData::Populated( + ref directory_digest, + ref children, + )) => { + // ensure the directory digest matches + assert_eq!(&fixtures::DIRECTORY_WITH_KEEP.digest(), directory_digest); + + // ensure the child is populated, with a different inode than + // the parent, and the data matches expectations. + assert_eq!(1, children.len()); + let (child_node_inode, child_node) = children.first().unwrap(); + assert_ne!(dir_complicated_ino, *child_node_inode); + assert_eq!( + &castorepb::node::Node::File( + fixtures::DIRECTORY_WITH_KEEP.files.first().unwrap().clone() + ), + child_node + ); + } + InodeData::Directory(DirectoryInodeData::Sparse(..)) + | InodeData::Regular(..) + | InodeData::Symlink(_) => panic!("wrong type"), + } + } +} + +// TODO: add test inserting a populated one first, then ensure an update doesn't degrade it back to sparse. diff --git a/tvix/store/src/fs/inodes.rs b/tvix/store/src/fs/inodes.rs new file mode 100644 index 000000000000..928f51059002 --- /dev/null +++ b/tvix/store/src/fs/inodes.rs @@ -0,0 +1,70 @@ +//! This module contains all the data structures used to track information +//! about inodes, which present tvix-store nodes in a filesystem. +use tvix_castore::proto as castorepb; +use tvix_castore::B3Digest; + +#[derive(Clone, Debug)] +pub enum InodeData { + Regular(B3Digest, u32, bool), // digest, size, executable + Symlink(bytes::Bytes), // target + Directory(DirectoryInodeData), // either [DirectoryInodeData:Sparse] or [DirectoryInodeData:Populated] +} + +/// This encodes the two different states of [InodeData::Directory]. +/// Either the data still is sparse (we only saw a [castorepb::DirectoryNode], +/// but didn't fetch the [castorepb::Directory] struct yet, or we processed a +/// lookup and did fetch the data. +#[derive(Clone, Debug)] +pub enum DirectoryInodeData { + Sparse(B3Digest, u32), // digest, size + Populated(B3Digest, Vec<(u64, castorepb::node::Node)>), // [(child_inode, node)] +} + +impl From<&castorepb::node::Node> for InodeData { + fn from(value: &castorepb::node::Node) -> Self { + match value { + castorepb::node::Node::Directory(directory_node) => directory_node.into(), + castorepb::node::Node::File(file_node) => file_node.into(), + castorepb::node::Node::Symlink(symlink_node) => symlink_node.into(), + } + } +} + +impl From<&castorepb::SymlinkNode> for InodeData { + fn from(value: &castorepb::SymlinkNode) -> Self { + InodeData::Symlink(value.target.clone()) + } +} + +impl From<&castorepb::FileNode> for InodeData { + fn from(value: &castorepb::FileNode) -> Self { + InodeData::Regular( + value.digest.clone().try_into().unwrap(), + value.size, + value.executable, + ) + } +} + +/// Converts a DirectoryNode to a sparsely populated InodeData::Directory. +impl From<&castorepb::DirectoryNode> for InodeData { + fn from(value: &castorepb::DirectoryNode) -> Self { + InodeData::Directory(DirectoryInodeData::Sparse( + value.digest.clone().try_into().unwrap(), + value.size, + )) + } +} + +/// converts a proto::Directory to a InodeData::Directory(DirectoryInodeData::Populated(..)). +/// The inodes for each child are 0, because it's up to the InodeTracker to allocate them. +impl From<castorepb::Directory> for InodeData { + fn from(value: castorepb::Directory) -> Self { + let digest = value.digest(); + + let children: Vec<(u64, castorepb::node::Node)> = + value.nodes().map(|node| (0, node)).collect(); + + InodeData::Directory(DirectoryInodeData::Populated(digest, children)) + } +} diff --git a/tvix/store/src/fs/mod.rs b/tvix/store/src/fs/mod.rs new file mode 100644 index 000000000000..1333983460ea --- /dev/null +++ b/tvix/store/src/fs/mod.rs @@ -0,0 +1,690 @@ +mod file_attr; +mod inode_tracker; +mod inodes; + +#[cfg(feature = "fuse")] +pub mod fuse; + +#[cfg(feature = "virtiofs")] +pub mod virtiofs; + +#[cfg(test)] +mod tests; + +use crate::pathinfoservice::PathInfoService; + +use fuse_backend_rs::abi::fuse_abi::stat64; +use fuse_backend_rs::api::filesystem::{Context, FileSystem, FsOptions, ROOT_ID}; +use futures::StreamExt; +use nix_compat::store_path::StorePath; +use parking_lot::RwLock; +use std::{ + collections::HashMap, + io, + str::FromStr, + sync::atomic::AtomicU64, + sync::{atomic::Ordering, Arc}, + time::Duration, +}; +use tokio::{ + io::{AsyncBufReadExt, AsyncSeekExt}, + sync::mpsc, +}; +use tracing::{debug, info_span, warn}; +use tvix_castore::{ + blobservice::{BlobReader, BlobService}, + directoryservice::DirectoryService, + proto::{node::Node, NamedNode}, + B3Digest, Error, +}; + +use self::{ + file_attr::{gen_file_attr, ROOT_FILE_ATTR}, + inode_tracker::InodeTracker, + inodes::{DirectoryInodeData, InodeData}, +}; + +/// This implements a read-only FUSE filesystem for a tvix-store +/// with the passed [BlobService], [DirectoryService] and [PathInfoService]. +/// +/// We don't allow listing on the root mountpoint (inode 0). +/// In the future, this might be made configurable once a listing method is +/// added to [self.path_info_service], and then show all store paths in that +/// store. +/// +/// Linux uses inodes in filesystems. When implementing FUSE, most calls are +/// *for* a given inode. +/// +/// This means, we need to have a stable mapping of inode numbers to the +/// corresponding store nodes. +/// +/// We internally delegate all inode allocation and state keeping to the +/// inode tracker, and store the currently "explored" store paths together with +/// root inode of the root. +/// +/// There's some places where inodes are allocated / data inserted into +/// the inode tracker, if not allocated before already: +/// - Processing a `lookup` request, either in the mount root, or somewhere +/// deeper +/// - Processing a `readdir` request +/// +/// Things pointing to the same contents get the same inodes, irrespective of +/// their own location. +/// This means: +/// - Symlinks with the same target will get the same inode. +/// - Regular/executable files with the same contents will get the same inode +/// - Directories with the same contents will get the same inode. +/// +/// Due to the above being valid across the whole store, and considering the +/// merkle structure is a DAG, not a tree, this also means we can't do "bucketed +/// allocation", aka reserve Directory.size inodes for each PathInfo. +pub struct TvixStoreFs { + blob_service: Arc<dyn BlobService>, + directory_service: Arc<dyn DirectoryService>, + path_info_service: Arc<dyn PathInfoService>, + + /// Whether to (try) listing elements in the root. + list_root: bool, + + /// This maps a given StorePath to the inode we allocated for the root inode. + store_paths: RwLock<HashMap<StorePath, u64>>, + + /// This keeps track of inodes and data alongside them. + inode_tracker: RwLock<InodeTracker>, + + /// This holds all open file handles + file_handles: RwLock<HashMap<u64, Arc<tokio::sync::Mutex<Box<dyn BlobReader>>>>>, + + next_file_handle: AtomicU64, + + tokio_handle: tokio::runtime::Handle, +} + +impl TvixStoreFs { + pub fn new( + blob_service: Arc<dyn BlobService>, + directory_service: Arc<dyn DirectoryService>, + path_info_service: Arc<dyn PathInfoService>, + list_root: bool, + ) -> Self { + Self { + blob_service, + directory_service, + path_info_service, + + list_root, + + store_paths: RwLock::new(HashMap::default()), + inode_tracker: RwLock::new(Default::default()), + + file_handles: RwLock::new(Default::default()), + next_file_handle: AtomicU64::new(1), + tokio_handle: tokio::runtime::Handle::current(), + } + } + + /// This will turn a lookup request for [std::ffi::OsStr] in the root to + /// a ino and [InodeData]. + /// It will peek in [self.store_paths], and then either look it up from + /// [self.inode_tracker], + /// or otherwise fetch from [self.path_info_service], and then insert into + /// [self.inode_tracker]. + fn name_in_root_to_ino_and_data( + &self, + name: &std::ffi::CStr, + ) -> Result<Option<(u64, Arc<InodeData>)>, Error> { + // parse the name into a [StorePath]. + let store_path = if let Some(name) = name.to_str().ok() { + match StorePath::from_str(name) { + Ok(store_path) => store_path, + Err(e) => { + debug!(e=?e, "unable to parse as store path"); + // This is not an error, but a "ENOENT", as someone can stat + // a file inside the root that's no valid store path + return Ok(None); + } + } + } else { + debug!("{name:?} is not a valid utf-8 string"); + // same here. + return Ok(None); + }; + + let ino = { + // This extra scope makes sure we drop the read lock + // immediately after reading, to prevent deadlocks. + let store_paths = self.store_paths.read(); + store_paths.get(&store_path).cloned() + }; + + if let Some(ino) = ino { + // If we already have that store path, lookup the inode from + // self.store_paths and then get the data from [self.inode_tracker], + // which in the case of a [InodeData::Directory] will be fully + // populated. + Ok(Some(( + ino, + self.inode_tracker.read().get(ino).expect("must exist"), + ))) + } else { + // If we don't have it, look it up in PathInfoService. + let path_info_service = self.path_info_service.clone(); + let task = self + .tokio_handle + .spawn(async move { path_info_service.get(store_path.digest).await }); + match self.tokio_handle.block_on(task).unwrap()? { + // the pathinfo doesn't exist, so the file doesn't exist. + None => Ok(None), + Some(path_info) => { + // The pathinfo does exist, so there must be a root node + let root_node = path_info.node.unwrap().node.unwrap(); + + // The name must match what's passed in the lookup, otherwise we return nothing. + if root_node.get_name() != store_path.to_string().as_bytes() { + return Ok(None); + } + + // Let's check if someone else beat us to updating the inode tracker and + // store_paths map. + let mut store_paths = self.store_paths.write(); + if let Some(ino) = store_paths.get(&store_path).cloned() { + return Ok(Some(( + ino, + self.inode_tracker.read().get(ino).expect("must exist"), + ))); + } + + // insert the (sparse) inode data and register in + // self.store_paths. + // FUTUREWORK: change put to return the data after + // inserting, so we don't need to lookup a second + // time? + let (ino, inode) = { + let mut inode_tracker = self.inode_tracker.write(); + let ino = inode_tracker.put((&root_node).into()); + (ino, inode_tracker.get(ino).unwrap()) + }; + store_paths.insert(store_path, ino); + + Ok(Some((ino, inode))) + } + } + } + } + + /// This will lookup a directory by digest, and will turn it into a + /// [InodeData::Directory(DirectoryInodeData::Populated(..))]. + /// This is both used to initially insert the root node of a store path, + /// as well as when looking up an intermediate DirectoryNode. + fn fetch_directory_inode_data(&self, directory_digest: &B3Digest) -> Result<InodeData, Error> { + let directory_service = self.directory_service.clone(); + let directory_digest_clone = directory_digest.clone(); + let task = self + .tokio_handle + .spawn(async move { directory_service.get(&directory_digest_clone).await }); + match self.tokio_handle.block_on(task).unwrap() { + Err(e) => { + warn!(e = e.to_string(), directory.digest=%directory_digest, "failed to get directory"); + Err(e) + } + // If the Directory can't be found, this is a hole, bail out. + Ok(None) => { + tracing::error!(directory.digest=%directory_digest, "directory not found in directory service"); + Err(Error::StorageError(format!( + "directory {} not found", + directory_digest + ))) + } + Ok(Some(directory)) => Ok(directory.into()), + } + } +} + +impl FileSystem for TvixStoreFs { + type Inode = u64; + type Handle = u64; + + fn init(&self, _capable: FsOptions) -> io::Result<FsOptions> { + Ok(FsOptions::empty()) + } + + #[tracing::instrument(skip_all, fields(rq.inode = inode))] + fn getattr( + &self, + _ctx: &Context, + inode: Self::Inode, + _handle: Option<Self::Handle>, + ) -> io::Result<(stat64, Duration)> { + if inode == ROOT_ID { + return Ok((ROOT_FILE_ATTR.into(), Duration::MAX)); + } + + match self.inode_tracker.read().get(inode) { + None => return Err(io::Error::from_raw_os_error(libc::ENOENT)), + Some(node) => { + debug!(node = ?node, "found node"); + Ok((gen_file_attr(&node, inode).into(), Duration::MAX)) + } + } + } + + #[tracing::instrument(skip_all, fields(rq.parent_inode = parent, rq.name = ?name))] + fn lookup( + &self, + _ctx: &Context, + parent: Self::Inode, + name: &std::ffi::CStr, + ) -> io::Result<fuse_backend_rs::api::filesystem::Entry> { + debug!("lookup"); + + // This goes from a parent inode to a node. + // - If the parent is [ROOT_ID], we need to check + // [self.store_paths] (fetching from PathInfoService if needed) + // - Otherwise, lookup the parent in [self.inode_tracker] (which must be + // a [InodeData::Directory]), and find the child with that name. + if parent == ROOT_ID { + return match self.name_in_root_to_ino_and_data(name) { + Err(e) => { + warn!("{}", e); + Err(io::Error::from_raw_os_error(libc::ENOENT)) + } + Ok(None) => Err(io::Error::from_raw_os_error(libc::ENOENT)), + Ok(Some((ino, inode_data))) => { + debug!(inode_data=?&inode_data, ino=ino, "Some"); + Ok(fuse_backend_rs::api::filesystem::Entry { + inode: ino, + attr: gen_file_attr(&inode_data, ino).into(), + attr_timeout: Duration::MAX, + entry_timeout: Duration::MAX, + ..Default::default() + }) + } + }; + } + + // This is the "lookup for "a" inside inode 42. + // We already know that inode 42 must be a directory. + // It might not be populated yet, so if it isn't, we do (by + // fetching from [self.directory_service]), and save the result in + // [self.inode_tracker]. + // Now it for sure is populated, so we search for that name in the + // list of children and return the FileAttrs. + + // TODO: Reduce the critical section of this write lock. + let mut inode_tracker = self.inode_tracker.write(); + let parent_data = inode_tracker.get(parent).unwrap(); + let parent_data = match *parent_data { + InodeData::Regular(..) | InodeData::Symlink(_) => { + // if the parent inode was not a directory, this doesn't make sense + return Err(io::Error::from_raw_os_error(libc::ENOTDIR)); + } + InodeData::Directory(DirectoryInodeData::Sparse(ref parent_digest, _)) => { + match self.fetch_directory_inode_data(parent_digest) { + Ok(new_data) => { + // update data in [self.inode_tracker] with populated variant. + // FUTUREWORK: change put to return the data after + // inserting, so we don't need to lookup a second + // time? + let ino = inode_tracker.put(new_data); + inode_tracker.get(ino).unwrap() + } + Err(_e) => { + return Err(io::Error::from_raw_os_error(libc::EIO)); + } + } + } + InodeData::Directory(DirectoryInodeData::Populated(..)) => parent_data, + }; + + // now parent_data can only be a [InodeData::Directory(DirectoryInodeData::Populated(..))]. + let (parent_digest, children) = if let InodeData::Directory( + DirectoryInodeData::Populated(ref parent_digest, ref children), + ) = *parent_data + { + (parent_digest, children) + } else { + panic!("unexpected type") + }; + let span = info_span!("lookup", directory.digest = %parent_digest); + let _enter = span.enter(); + + // in the children, find the one with the desired name. + if let Some((child_ino, _)) = children.iter().find(|e| e.1.get_name() == name.to_bytes()) { + // lookup the child [InodeData] in [self.inode_tracker]. + // We know the inodes for children have already been allocated. + let child_inode_data = inode_tracker.get(*child_ino).unwrap(); + + // Reply with the file attributes for the child. + // For child directories, we still have all data we need to reply. + Ok(fuse_backend_rs::api::filesystem::Entry { + inode: *child_ino, + attr: gen_file_attr(&child_inode_data, *child_ino).into(), + attr_timeout: Duration::MAX, + entry_timeout: Duration::MAX, + ..Default::default() + }) + } else { + // Child not found, return ENOENT. + Err(io::Error::from_raw_os_error(libc::ENOENT)) + } + } + + // TODO: readdirplus? + + #[tracing::instrument(skip_all, fields(rq.inode = inode, rq.offset = offset))] + fn readdir( + &self, + _ctx: &Context, + inode: Self::Inode, + _handle: Self::Handle, + _size: u32, + offset: u64, + add_entry: &mut dyn FnMut(fuse_backend_rs::api::filesystem::DirEntry) -> io::Result<usize>, + ) -> io::Result<()> { + debug!("readdir"); + + if inode == ROOT_ID { + if !self.list_root { + return Err(io::Error::from_raw_os_error(libc::EPERM)); // same error code as ipfs/kubo + } else { + let path_info_service = self.path_info_service.clone(); + let (tx, mut rx) = mpsc::channel(16); + + // This task will run in the background immediately and will exit + // after the stream ends or if we no longer want any more entries. + self.tokio_handle.spawn(async move { + let mut stream = path_info_service.list().skip(offset as usize).enumerate(); + while let Some(path_info) = stream.next().await { + if tx.send(path_info).await.is_err() { + // If we get a send error, it means the sync code + // doesn't want any more entries. + break; + } + } + }); + + while let Some((i, path_info)) = rx.blocking_recv() { + let path_info = match path_info { + Err(e) => { + warn!("failed to retrieve pathinfo: {}", e); + return Err(io::Error::from_raw_os_error(libc::EPERM)); + } + Ok(path_info) => path_info, + }; + + // We know the root node exists and the store_path can be parsed because clients MUST validate. + let root_node = path_info.node.unwrap().node.unwrap(); + let store_path = StorePath::from_bytes(root_node.get_name()).unwrap(); + + let ino = { + // This extra scope makes sure we drop the read lock + // immediately after reading, to prevent deadlocks. + let store_paths = self.store_paths.read(); + store_paths.get(&store_path).cloned() + }; + let ino = match ino { + Some(ino) => ino, + None => { + // insert the (sparse) inode data and register in + // self.store_paths. + let ino = self.inode_tracker.write().put((&root_node).into()); + self.store_paths.write().insert(store_path.clone(), ino); + ino + } + }; + + let ty = match root_node { + Node::Directory(_) => libc::S_IFDIR, + Node::File(_) => libc::S_IFREG, + Node::Symlink(_) => libc::S_IFLNK, + }; + + let written = add_entry(fuse_backend_rs::api::filesystem::DirEntry { + ino, + offset: offset + i as u64 + 1, + type_: ty as u32, + name: store_path.to_string().as_bytes(), + })?; + // If the buffer is full, add_entry will return `Ok(0)`. + if written == 0 { + break; + } + } + + return Ok(()); + } + } + + // lookup the inode data. + let mut inode_tracker = self.inode_tracker.write(); + let dir_inode_data = inode_tracker.get(inode).unwrap(); + let dir_inode_data = match *dir_inode_data { + InodeData::Regular(..) | InodeData::Symlink(..) => { + warn!("Not a directory"); + return Err(io::Error::from_raw_os_error(libc::ENOTDIR)); + } + InodeData::Directory(DirectoryInodeData::Sparse(ref directory_digest, _)) => { + match self.fetch_directory_inode_data(directory_digest) { + Ok(new_data) => { + // update data in [self.inode_tracker] with populated variant. + // FUTUREWORK: change put to return the data after + // inserting, so we don't need to lookup a second + // time? + let ino = inode_tracker.put(new_data.clone()); + inode_tracker.get(ino).unwrap() + } + Err(_e) => { + return Err(io::Error::from_raw_os_error(libc::EIO)); + } + } + } + InodeData::Directory(DirectoryInodeData::Populated(..)) => dir_inode_data, + }; + + // now parent_data can only be InodeData::Directory(DirectoryInodeData::Populated(..)) + if let InodeData::Directory(DirectoryInodeData::Populated(ref _digest, ref children)) = + *dir_inode_data + { + for (i, (ino, child_node)) in children.iter().skip(offset as usize).enumerate() { + // the second parameter will become the "offset" parameter on the next call. + let written = add_entry(fuse_backend_rs::api::filesystem::DirEntry { + ino: *ino, + offset: offset + i as u64 + 1, + type_: match child_node { + Node::Directory(_) => libc::S_IFDIR as u32, + Node::File(_) => libc::S_IFREG as u32, + Node::Symlink(_) => libc::S_IFLNK as u32, + }, + name: child_node.get_name(), + })?; + // If the buffer is full, add_entry will return `Ok(0)`. + if written == 0 { + break; + } + } + } else { + panic!("unexpected type") + } + + Ok(()) + } + + #[tracing::instrument(skip_all, fields(rq.inode = inode))] + fn open( + &self, + _ctx: &Context, + inode: Self::Inode, + _flags: u32, + _fuse_flags: u32, + ) -> io::Result<( + Option<Self::Handle>, + fuse_backend_rs::api::filesystem::OpenOptions, + )> { + if inode == ROOT_ID { + return Err(io::Error::from_raw_os_error(libc::ENOSYS)); + } + + // lookup the inode + match *self.inode_tracker.read().get(inode).unwrap() { + // read is invalid on non-files. + InodeData::Directory(..) | InodeData::Symlink(_) => { + warn!("is directory"); + return Err(io::Error::from_raw_os_error(libc::EISDIR)); + } + InodeData::Regular(ref blob_digest, _blob_size, _) => { + let span = info_span!("read", blob.digest = %blob_digest); + let _enter = span.enter(); + + let blob_service = self.blob_service.clone(); + let blob_digest = blob_digest.clone(); + + let task = self + .tokio_handle + .spawn(async move { blob_service.open_read(&blob_digest).await }); + + let blob_reader = self.tokio_handle.block_on(task).unwrap(); + + match blob_reader { + Ok(None) => { + warn!("blob not found"); + return Err(io::Error::from_raw_os_error(libc::EIO)); + } + Err(e) => { + warn!(e=?e, "error opening blob"); + return Err(io::Error::from_raw_os_error(libc::EIO)); + } + Ok(Some(blob_reader)) => { + // get a new file handle + // TODO: this will overflow after 2**64 operations, + // which is fine for now. + // See https://cl.tvl.fyi/c/depot/+/8834/comment/a6684ce0_d72469d1 + // for the discussion on alternatives. + let fh = self.next_file_handle.fetch_add(1, Ordering::SeqCst); + + debug!("add file handle {}", fh); + self.file_handles + .write() + .insert(fh, Arc::new(tokio::sync::Mutex::new(blob_reader))); + + Ok(( + Some(fh), + fuse_backend_rs::api::filesystem::OpenOptions::empty(), + )) + } + } + } + } + } + + #[tracing::instrument(skip_all, fields(rq.inode = inode, fh = handle))] + fn release( + &self, + _ctx: &Context, + inode: Self::Inode, + _flags: u32, + handle: Self::Handle, + _flush: bool, + _flock_release: bool, + _lock_owner: Option<u64>, + ) -> io::Result<()> { + // remove and get ownership on the blob reader + match self.file_handles.write().remove(&handle) { + // drop it, which will close it. + Some(blob_reader) => drop(blob_reader), + None => { + // These might already be dropped if a read error occured. + debug!("file_handle {} not found", handle); + } + } + + Ok(()) + } + + #[tracing::instrument(skip_all, fields(rq.inode = inode, rq.offset = offset, rq.size = size))] + fn read( + &self, + _ctx: &Context, + inode: Self::Inode, + handle: Self::Handle, + w: &mut dyn fuse_backend_rs::api::filesystem::ZeroCopyWriter, + size: u32, + offset: u64, + _lock_owner: Option<u64>, + _flags: u32, + ) -> io::Result<usize> { + debug!("read"); + + // We need to take out the blob reader from self.file_handles, so we can + // interact with it in the separate task. + // On success, we pass it back out of the task, so we can put it back in self.file_handles. + let blob_reader = match self.file_handles.read().get(&handle) { + Some(blob_reader) => blob_reader.clone(), + None => { + warn!("file handle {} unknown", handle); + return Err(io::Error::from_raw_os_error(libc::EIO)); + } + }; + + let task = self.tokio_handle.spawn(async move { + let mut blob_reader = blob_reader.lock().await; + + // seek to the offset specified, which is relative to the start of the file. + let resp = blob_reader.seek(io::SeekFrom::Start(offset as u64)).await; + + match resp { + Ok(pos) => { + debug_assert_eq!(offset as u64, pos); + } + Err(e) => { + warn!("failed to seek to offset {}: {}", offset, e); + return Err(io::Error::from_raw_os_error(libc::EIO)); + } + } + + // As written in the fuse docs, read should send exactly the number + // of bytes requested except on EOF or error. + + let mut buf: Vec<u8> = Vec::with_capacity(size as usize); + + while (buf.len() as u64) < size as u64 { + let int_buf = blob_reader.fill_buf().await?; + // copy things from the internal buffer into buf to fill it till up until size + + // an empty buffer signals we reached EOF. + if int_buf.is_empty() { + break; + } + + // calculate how many bytes we can read from int_buf. + // It's either all of int_buf, or the number of bytes missing in buf to reach size. + let len_to_copy = std::cmp::min(int_buf.len(), size as usize - buf.len()); + + // copy these bytes into our buffer + buf.extend_from_slice(&int_buf[..len_to_copy]); + // and consume them in the buffered reader. + blob_reader.consume(len_to_copy); + } + + Ok(buf) + }); + + let buf = self.tokio_handle.block_on(task).unwrap()?; + + w.write(&buf) + } + + #[tracing::instrument(skip_all, fields(rq.inode = inode))] + fn readlink(&self, _ctx: &Context, inode: Self::Inode) -> io::Result<Vec<u8>> { + if inode == ROOT_ID { + return Err(io::Error::from_raw_os_error(libc::ENOSYS)); + } + + // lookup the inode + match *self.inode_tracker.read().get(inode).unwrap() { + InodeData::Directory(..) | InodeData::Regular(..) => { + Err(io::Error::from_raw_os_error(libc::EINVAL)) + } + InodeData::Symlink(ref target) => Ok(target.to_vec()), + } + } +} diff --git a/tvix/store/src/fs/tests.rs b/tvix/store/src/fs/tests.rs new file mode 100644 index 000000000000..2adea0ceb3a9 --- /dev/null +++ b/tvix/store/src/fs/tests.rs @@ -0,0 +1,1171 @@ +use futures::StreamExt; +use std::io::Cursor; +use std::os::unix::prelude::MetadataExt; +use std::path::Path; +use std::sync::Arc; +use tokio::{fs, io}; +use tokio_stream::wrappers::ReadDirStream; +use tvix_castore::blobservice::BlobService; +use tvix_castore::directoryservice::DirectoryService; + +use tempfile::TempDir; + +use crate::fs::{fuse::FuseDaemon, TvixStoreFs}; +use crate::pathinfoservice::PathInfoService; +use crate::proto::PathInfo; +use crate::tests::fixtures; +use crate::tests::utils::{gen_blob_service, gen_directory_service, gen_pathinfo_service}; +use tvix_castore::proto as castorepb; + +const BLOB_A_NAME: &str = "00000000000000000000000000000000-test"; +const BLOB_B_NAME: &str = "55555555555555555555555555555555-test"; +const HELLOWORLD_BLOB_NAME: &str = "66666666666666666666666666666666-test"; +const SYMLINK_NAME: &str = "11111111111111111111111111111111-test"; +const SYMLINK_NAME2: &str = "44444444444444444444444444444444-test"; +const DIRECTORY_WITH_KEEP_NAME: &str = "22222222222222222222222222222222-test"; +const DIRECTORY_COMPLICATED_NAME: &str = "33333333333333333333333333333333-test"; + +fn gen_svcs() -> ( + Arc<dyn BlobService>, + Arc<dyn DirectoryService>, + Arc<dyn PathInfoService>, +) { + let blob_service = gen_blob_service(); + let directory_service = gen_directory_service(); + let path_info_service = gen_pathinfo_service(blob_service.clone(), directory_service.clone()); + + (blob_service, directory_service, path_info_service) +} + +fn do_mount<P: AsRef<Path>>( + blob_service: Arc<dyn BlobService>, + directory_service: Arc<dyn DirectoryService>, + path_info_service: Arc<dyn PathInfoService>, + mountpoint: P, + list_root: bool, +) -> io::Result<FuseDaemon> { + let fs = TvixStoreFs::new( + blob_service, + directory_service, + path_info_service, + list_root, + ); + FuseDaemon::new(fs, mountpoint.as_ref(), 4) +} + +async fn populate_blob_a( + blob_service: &Arc<dyn BlobService>, + _directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // Upload BLOB_A + let mut bw = blob_service.open_write().await; + tokio::io::copy(&mut Cursor::new(fixtures::BLOB_A.to_vec()), &mut bw) + .await + .expect("must succeed uploading"); + bw.close().await.expect("must succeed closing"); + + // Create a PathInfo for it + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::File(castorepb::FileNode { + name: BLOB_A_NAME.into(), + digest: fixtures::BLOB_A_DIGEST.clone().into(), + size: fixtures::BLOB_A.len() as u32, + executable: false, + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +async fn populate_blob_b( + blob_service: &Arc<dyn BlobService>, + _directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // Upload BLOB_B + let mut bw = blob_service.open_write().await; + tokio::io::copy(&mut Cursor::new(fixtures::BLOB_B.to_vec()), &mut bw) + .await + .expect("must succeed uploading"); + bw.close().await.expect("must succeed closing"); + + // Create a PathInfo for it + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::File(castorepb::FileNode { + name: BLOB_B_NAME.into(), + digest: fixtures::BLOB_B_DIGEST.clone().into(), + size: fixtures::BLOB_B.len() as u32, + executable: false, + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +/// adds a blob containing helloworld and marks it as executable +async fn populate_helloworld_blob( + blob_service: &Arc<dyn BlobService>, + _directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // Upload BLOB_B + let mut bw = blob_service.open_write().await; + tokio::io::copy( + &mut Cursor::new(fixtures::HELLOWORLD_BLOB_CONTENTS.to_vec()), + &mut bw, + ) + .await + .expect("must succeed uploading"); + bw.close().await.expect("must succeed closing"); + + // Create a PathInfo for it + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::File(castorepb::FileNode { + name: HELLOWORLD_BLOB_NAME.into(), + digest: fixtures::HELLOWORLD_BLOB_DIGEST.clone().into(), + size: fixtures::HELLOWORLD_BLOB_CONTENTS.len() as u32, + executable: true, + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +async fn populate_symlink( + _blob_service: &Arc<dyn BlobService>, + _directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // Create a PathInfo for it + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::Symlink(castorepb::SymlinkNode { + name: SYMLINK_NAME.into(), + target: BLOB_A_NAME.into(), + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +/// This writes a symlink pointing to /nix/store/somewhereelse, +/// which is the same symlink target as "aa" inside DIRECTORY_COMPLICATED. +async fn populate_symlink2( + _blob_service: &Arc<dyn BlobService>, + _directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // Create a PathInfo for it + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::Symlink(castorepb::SymlinkNode { + name: SYMLINK_NAME2.into(), + target: "/nix/store/somewhereelse".into(), + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +async fn populate_directory_with_keep( + blob_service: &Arc<dyn BlobService>, + directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // upload empty blob + let mut bw = blob_service.open_write().await; + assert_eq!( + fixtures::EMPTY_BLOB_DIGEST.to_vec(), + bw.close().await.expect("must succeed closing").to_vec(), + ); + + // upload directory + directory_service + .put(fixtures::DIRECTORY_WITH_KEEP.clone()) + .await + .expect("must succeed uploading"); + + // upload pathinfo + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::Directory(castorepb::DirectoryNode { + name: DIRECTORY_WITH_KEEP_NAME.into(), + digest: fixtures::DIRECTORY_WITH_KEEP.digest().into(), + size: fixtures::DIRECTORY_WITH_KEEP.size(), + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +/// Insert [PathInfo] for DIRECTORY_WITH_KEEP, but don't provide the Directory +/// itself. +async fn populate_pathinfo_without_directory( + _: &Arc<dyn BlobService>, + _: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // upload pathinfo + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::Directory(castorepb::DirectoryNode { + name: DIRECTORY_WITH_KEEP_NAME.into(), + digest: fixtures::DIRECTORY_WITH_KEEP.digest().into(), + size: fixtures::DIRECTORY_WITH_KEEP.size(), + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +/// Insert , but don't provide the blob .keep is pointing to +async fn populate_blob_a_without_blob( + _: &Arc<dyn BlobService>, + _: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // Create a PathInfo for blob A + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::File(castorepb::FileNode { + name: BLOB_A_NAME.into(), + digest: fixtures::BLOB_A_DIGEST.clone().into(), + size: fixtures::BLOB_A.len() as u32, + executable: false, + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +async fn populate_directory_complicated( + blob_service: &Arc<dyn BlobService>, + directory_service: &Arc<dyn DirectoryService>, + path_info_service: &Arc<dyn PathInfoService>, +) { + // upload empty blob + let mut bw = blob_service.open_write().await; + assert_eq!( + fixtures::EMPTY_BLOB_DIGEST.to_vec(), + bw.close().await.expect("must succeed closing").to_vec(), + ); + + // upload inner directory + directory_service + .put(fixtures::DIRECTORY_WITH_KEEP.clone()) + .await + .expect("must succeed uploading"); + + // uplodad parent directory + directory_service + .put(fixtures::DIRECTORY_COMPLICATED.clone()) + .await + .expect("must succeed uploading"); + + // upload pathinfo + let path_info = PathInfo { + node: Some(castorepb::Node { + node: Some(castorepb::node::Node::Directory(castorepb::DirectoryNode { + name: DIRECTORY_COMPLICATED_NAME.into(), + digest: fixtures::DIRECTORY_COMPLICATED.digest().into(), + size: fixtures::DIRECTORY_COMPLICATED.size(), + })), + }), + ..Default::default() + }; + path_info_service + .put(path_info) + .await + .expect("must succeed"); +} + +/// Ensure mounting itself doesn't fail +#[tokio::test] +async fn mount() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure listing the root isn't allowed +#[tokio::test] +async fn root() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + { + // read_dir succeeds, but getting the first element will fail. + let mut it = ReadDirStream::new(fs::read_dir(tmpdir).await.expect("must succeed")); + + let err = it + .next() + .await + .expect("must be some") + .expect_err("must be err"); + assert_eq!(std::io::ErrorKind::PermissionDenied, err.kind()); + } + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure listing the root is allowed if configured explicitly +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +async fn root_with_listing() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + true, /* allow listing */ + ) + .expect("must succeed"); + + { + // read_dir succeeds, but getting the first element will fail. + let mut it = ReadDirStream::new(fs::read_dir(tmpdir).await.expect("must succeed")); + + let e = it + .next() + .await + .expect("must be some") + .expect("must succeed"); + + let metadata = e.metadata().await.expect("must succeed"); + assert!(metadata.is_file()); + assert!(metadata.permissions().readonly()); + assert_eq!(fixtures::BLOB_A.len() as u64, metadata.len()); + } + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure we can stat a file at the root +#[tokio::test] +async fn stat_file_at_root() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(BLOB_A_NAME); + + // peek at the file metadata + let metadata = fs::metadata(p).await.expect("must succeed"); + + assert!(metadata.is_file()); + assert!(metadata.permissions().readonly()); + assert_eq!(fixtures::BLOB_A.len() as u64, metadata.len()); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure we can read a file at the root +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +async fn read_file_at_root() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(BLOB_A_NAME); + + // read the file contents + let data = fs::read(p).await.expect("must succeed"); + + // ensure size and contents match + assert_eq!(fixtures::BLOB_A.len(), data.len()); + assert_eq!(fixtures::BLOB_A.to_vec(), data); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure we can read a large file at the root +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +async fn read_large_file_at_root() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_b(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(BLOB_B_NAME); + { + // peek at the file metadata + let metadata = fs::metadata(&p).await.expect("must succeed"); + + assert!(metadata.is_file()); + assert!(metadata.permissions().readonly()); + assert_eq!(fixtures::BLOB_B.len() as u64, metadata.len()); + } + + // read the file contents + let data = fs::read(p).await.expect("must succeed"); + + // ensure size and contents match + assert_eq!(fixtures::BLOB_B.len(), data.len()); + assert_eq!(fixtures::BLOB_B.to_vec(), data); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Read the target of a symlink +#[tokio::test] +async fn symlink_readlink() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_symlink(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(SYMLINK_NAME); + + let target = fs::read_link(&p).await.expect("must succeed"); + assert_eq!(BLOB_A_NAME, target.to_str().unwrap()); + + // peek at the file metadata, which follows symlinks. + // this must fail, as we didn't populate the target. + let e = fs::metadata(&p).await.expect_err("must fail"); + assert_eq!(std::io::ErrorKind::NotFound, e.kind()); + + // peeking at the file metadata without following symlinks will succeed. + let metadata = fs::symlink_metadata(&p).await.expect("must succeed"); + assert!(metadata.is_symlink()); + + // reading from the symlink (which follows) will fail, because the target doesn't exist. + let e = fs::read(p).await.expect_err("must fail"); + assert_eq!(std::io::ErrorKind::NotFound, e.kind()); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Read and stat a regular file through a symlink pointing to it. +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +async fn read_stat_through_symlink() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a(&blob_service, &directory_service, &path_info_service).await; + populate_symlink(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p_symlink = tmpdir.path().join(SYMLINK_NAME); + let p_blob = tmpdir.path().join(SYMLINK_NAME); + + // peek at the file metadata, which follows symlinks. + // this must now return the same metadata as when statting at the target directly. + let metadata_symlink = fs::metadata(&p_symlink).await.expect("must succeed"); + let metadata_blob = fs::metadata(&p_blob).await.expect("must succeed"); + assert_eq!(metadata_blob.file_type(), metadata_symlink.file_type()); + assert_eq!(metadata_blob.len(), metadata_symlink.len()); + + // reading from the symlink (which follows) will return the same data as if + // we were reading from the file directly. + assert_eq!( + fs::read(p_blob).await.expect("must succeed"), + fs::read(p_symlink).await.expect("must succeed"), + ); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Read a directory in the root, and validate some attributes. +#[tokio::test] +async fn read_stat_directory() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_with_keep(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(DIRECTORY_WITH_KEEP_NAME); + + // peek at the metadata of the directory + let metadata = fs::metadata(p).await.expect("must succeed"); + assert!(metadata.is_dir()); + assert!(metadata.permissions().readonly()); + + fuse_daemon.unmount().expect("unmount"); +} + +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +/// Read a blob inside a directory. This ensures we successfully populate directory data. +async fn read_blob_inside_dir() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_with_keep(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(DIRECTORY_WITH_KEEP_NAME).join(".keep"); + + // peek at metadata. + let metadata = fs::metadata(&p).await.expect("must succeed"); + assert!(metadata.is_file()); + assert!(metadata.permissions().readonly()); + + // read from it + let data = fs::read(&p).await.expect("must succeed"); + assert_eq!(fixtures::EMPTY_BLOB_CONTENTS.to_vec(), data); + + fuse_daemon.unmount().expect("unmount"); +} + +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +/// Read a blob inside a directory inside a directory. This ensures we properly +/// populate directories as we traverse down the structure. +async fn read_blob_deep_inside_dir() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_complicated(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir + .path() + .join(DIRECTORY_COMPLICATED_NAME) + .join("keep") + .join(".keep"); + + // peek at metadata. + let metadata = fs::metadata(&p).await.expect("must succeed"); + assert!(metadata.is_file()); + assert!(metadata.permissions().readonly()); + + // read from it + let data = fs::read(&p).await.expect("must succeed"); + assert_eq!(fixtures::EMPTY_BLOB_CONTENTS.to_vec(), data); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure readdir works. +#[tokio::test] +async fn readdir() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_complicated(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(DIRECTORY_COMPLICATED_NAME); + + { + // read_dir should succeed. Collect all elements + let elements: Vec<_> = ReadDirStream::new(fs::read_dir(p).await.expect("must succeed")) + .map(|e| e.expect("must not be err")) + .collect() + .await; + + assert_eq!(3, elements.len(), "number of elements should be 3"); // rust skips . and .. + + // We explicitly look at specific positions here, because we always emit + // them ordered. + + // ".keep", 0 byte file. + let e = &elements[0]; + assert_eq!(".keep", e.file_name()); + assert!(e.file_type().await.expect("must succeed").is_file()); + assert_eq!(0, e.metadata().await.expect("must succeed").len()); + + // "aa", symlink. + let e = &elements[1]; + assert_eq!("aa", e.file_name()); + assert!(e.file_type().await.expect("must succeed").is_symlink()); + + // "keep", directory + let e = &elements[2]; + assert_eq!("keep", e.file_name()); + assert!(e.file_type().await.expect("must succeed").is_dir()); + } + + fuse_daemon.unmount().expect("unmount"); +} + +#[tokio::test] +/// Do a readdir deeper inside a directory, without doing readdir or stat in the parent directory. +async fn readdir_deep() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_complicated(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(DIRECTORY_COMPLICATED_NAME).join("keep"); + + { + // read_dir should succeed. Collect all elements + let elements: Vec<_> = ReadDirStream::new(fs::read_dir(p).await.expect("must succeed")) + .map(|e| e.expect("must not be err")) + .collect() + .await; + + assert_eq!(1, elements.len(), "number of elements should be 1"); // rust skips . and .. + + // ".keep", 0 byte file. + let e = &elements[0]; + assert_eq!(".keep", e.file_name()); + assert!(e.file_type().await.expect("must succeed").is_file()); + assert_eq!(0, e.metadata().await.expect("must succeed").len()); + } + + fuse_daemon.unmount().expect("unmount"); +} + +/// Check attributes match how they show up in /nix/store normally. +#[tokio::test] +async fn check_attributes() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a(&blob_service, &directory_service, &path_info_service).await; + populate_directory_with_keep(&blob_service, &directory_service, &path_info_service).await; + populate_symlink(&blob_service, &directory_service, &path_info_service).await; + populate_helloworld_blob(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p_file = tmpdir.path().join(BLOB_A_NAME); + let p_directory = tmpdir.path().join(DIRECTORY_WITH_KEEP_NAME); + let p_symlink = tmpdir.path().join(SYMLINK_NAME); + let p_executable_file = tmpdir.path().join(HELLOWORLD_BLOB_NAME); + + // peek at metadata. We use symlink_metadata to ensure we don't traverse a symlink by accident. + let metadata_file = fs::symlink_metadata(&p_file).await.expect("must succeed"); + let metadata_executable_file = fs::symlink_metadata(&p_executable_file) + .await + .expect("must succeed"); + let metadata_directory = fs::symlink_metadata(&p_directory) + .await + .expect("must succeed"); + let metadata_symlink = fs::symlink_metadata(&p_symlink) + .await + .expect("must succeed"); + + // modes should match. We & with 0o777 to remove any higher bits. + assert_eq!(0o444, metadata_file.mode() & 0o777); + assert_eq!(0o555, metadata_executable_file.mode() & 0o777); + assert_eq!(0o555, metadata_directory.mode() & 0o777); + assert_eq!(0o444, metadata_symlink.mode() & 0o777); + + // files should have the correct filesize + assert_eq!(fixtures::BLOB_A.len() as u64, metadata_file.len()); + // directories should have their "size" as filesize + assert_eq!( + fixtures::DIRECTORY_WITH_KEEP.size() as u64, + metadata_directory.size() + ); + + for metadata in &[&metadata_file, &metadata_directory, &metadata_symlink] { + // uid and gid should be 0. + assert_eq!(0, metadata.uid()); + assert_eq!(0, metadata.gid()); + + // all times should be set to the unix epoch. + assert_eq!(0, metadata.atime()); + assert_eq!(0, metadata.mtime()); + assert_eq!(0, metadata.ctime()); + // crtime seems MacOS only + } + + fuse_daemon.unmount().expect("unmount"); +} + +#[tokio::test] +/// Ensure we allocate the same inodes for the same directory contents. +/// $DIRECTORY_COMPLICATED_NAME/keep contains the same data as $DIRECTORY_WITH_KEEP. +async fn compare_inodes_directories() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_with_keep(&blob_service, &directory_service, &path_info_service).await; + populate_directory_complicated(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p_dir_with_keep = tmpdir.path().join(DIRECTORY_WITH_KEEP_NAME); + let p_sibling_dir = tmpdir.path().join(DIRECTORY_COMPLICATED_NAME).join("keep"); + + // peek at metadata. + assert_eq!( + fs::metadata(p_dir_with_keep) + .await + .expect("must succeed") + .ino(), + fs::metadata(p_sibling_dir) + .await + .expect("must succeed") + .ino() + ); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure we allocate the same inodes for the same directory contents. +/// $DIRECTORY_COMPLICATED_NAME/keep/,keep contains the same data as $DIRECTORY_COMPLICATED_NAME/.keep +#[tokio::test] +async fn compare_inodes_files() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_complicated(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p_keep1 = tmpdir.path().join(DIRECTORY_COMPLICATED_NAME).join(".keep"); + let p_keep2 = tmpdir + .path() + .join(DIRECTORY_COMPLICATED_NAME) + .join("keep") + .join(".keep"); + + // peek at metadata. + assert_eq!( + fs::metadata(p_keep1).await.expect("must succeed").ino(), + fs::metadata(p_keep2).await.expect("must succeed").ino() + ); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Ensure we allocate the same inode for symlinks pointing to the same targets. +/// $DIRECTORY_COMPLICATED_NAME/aa points to the same target as SYMLINK_NAME2. +#[tokio::test] +async fn compare_inodes_symlinks() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_directory_complicated(&blob_service, &directory_service, &path_info_service).await; + populate_symlink2(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p1 = tmpdir.path().join(DIRECTORY_COMPLICATED_NAME).join("aa"); + let p2 = tmpdir.path().join(SYMLINK_NAME2); + + // peek at metadata. + assert_eq!( + fs::symlink_metadata(p1).await.expect("must succeed").ino(), + fs::symlink_metadata(p2).await.expect("must succeed").ino() + ); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Check we match paths exactly. +#[tokio::test] +async fn read_wrong_paths_in_root() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + // wrong name + assert!( + fs::metadata(tmpdir.path().join("00000000000000000000000000000000-tes")) + .await + .is_err() + ); + + // invalid hash + assert!( + fs::metadata(tmpdir.path().join("0000000000000000000000000000000-test")) + .await + .is_err() + ); + + // right name, must exist + assert!( + fs::metadata(tmpdir.path().join("00000000000000000000000000000000-test")) + .await + .is_ok() + ); + + // now wrong name with right hash still may not exist + assert!( + fs::metadata(tmpdir.path().join("00000000000000000000000000000000-tes")) + .await + .is_err() + ); + + fuse_daemon.unmount().expect("unmount"); +} + +/// Make sure writes are not allowed +#[tokio::test] +async fn disallow_writes() { + // https://plume.benboeckel.net/~/JustAnotherBlog/skipping-tests-in-rust + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(BLOB_A_NAME); + let e = fs::File::create(p).await.expect_err("must fail"); + + assert_eq!(Some(libc::EROFS), e.raw_os_error()); + + fuse_daemon.unmount().expect("unmount"); +} + +#[tokio::test] +/// Ensure we get an IO error if the directory service does not have the Directory object. +async fn missing_directory() { + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_pathinfo_without_directory(&blob_service, &directory_service, &path_info_service) + .await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(DIRECTORY_WITH_KEEP_NAME); + + { + // `stat` on the path should succeed, because it doesn't trigger the directory request. + fs::metadata(&p).await.expect("must succeed"); + + // However, calling either `readdir` or `stat` on a child should fail with an IO error. + // It fails when trying to pull the first entry, because we don't implement opendir separately + ReadDirStream::new(fs::read_dir(&p).await.unwrap()) + .next() + .await + .expect("must be some") + .expect_err("must be err"); + + // rust currently sets e.kind() to Uncategorized, which isn't very + // helpful, so we don't look at the error more closely than that.. + fs::metadata(p.join(".keep")).await.expect_err("must fail"); + } + + fuse_daemon.unmount().expect("unmount"); +} + +#[tokio::test(flavor = "multi_thread", worker_threads = 2)] +/// Ensure we get an IO error if the blob service does not have the blob +async fn missing_blob() { + if !std::path::Path::new("/dev/fuse").exists() { + eprintln!("skipping test"); + return; + } + let tmpdir = TempDir::new().unwrap(); + + let (blob_service, directory_service, path_info_service) = gen_svcs(); + populate_blob_a_without_blob(&blob_service, &directory_service, &path_info_service).await; + + let mut fuse_daemon = do_mount( + blob_service, + directory_service, + path_info_service, + tmpdir.path(), + false, + ) + .expect("must succeed"); + + let p = tmpdir.path().join(BLOB_A_NAME); + + { + // `stat` on the blob should succeed, because it doesn't trigger a request to the blob service. + fs::metadata(&p).await.expect("must succeed"); + + // However, calling read on the blob should fail. + // rust currently sets e.kind() to Uncategorized, which isn't very + // helpful, so we don't look at the error more closely than that.. + fs::read(p).await.expect_err("must fail"); + } + + fuse_daemon.unmount().expect("unmount"); +} diff --git a/tvix/store/src/fs/virtiofs.rs b/tvix/store/src/fs/virtiofs.rs new file mode 100644 index 000000000000..3786a84285cd --- /dev/null +++ b/tvix/store/src/fs/virtiofs.rs @@ -0,0 +1,237 @@ +use std::{ + convert, error, fmt, io, + ops::Deref, + path::Path, + sync::{Arc, MutexGuard, RwLock}, +}; + +use fuse_backend_rs::{ + api::{filesystem::FileSystem, server::Server}, + transport::{FsCacheReqHandler, Reader, VirtioFsWriter}, +}; +use tracing::error; +use vhost::vhost_user::{ + Listener, SlaveFsCacheReq, VhostUserProtocolFeatures, VhostUserVirtioFeatures, +}; +use vhost_user_backend::{VhostUserBackendMut, VhostUserDaemon, VringMutex, VringState, VringT}; +use virtio_bindings::bindings::virtio_ring::{ + VIRTIO_RING_F_EVENT_IDX, VIRTIO_RING_F_INDIRECT_DESC, +}; +use virtio_queue::QueueT; +use vm_memory::{GuestAddressSpace, GuestMemoryAtomic, GuestMemoryMmap}; +use vmm_sys_util::epoll::EventSet; + +const VIRTIO_F_VERSION_1: u32 = 32; +const NUM_QUEUES: usize = 2; +const QUEUE_SIZE: usize = 1024; + +#[derive(Debug)] +enum Error { + /// Failed to handle non-input event. + HandleEventNotEpollIn, + /// Failed to handle unknown event. + HandleEventUnknownEvent, + /// Invalid descriptor chain. + InvlaidDescriptorChain, + /// Failed to handle filesystem requests. + HandleRequests(fuse_backend_rs::Error), + /// Failed to construct new vhost user daemon. + NewDaemon, + /// Failed to start the vhost user daemon. + StartDaemon, + /// Failed to wait for the vhost user daemon. + WaitDaemon, +} + +impl fmt::Display for Error { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "vhost_user_fs_error: {self:?}") + } +} + +impl error::Error for Error {} + +impl convert::From<Error> for io::Error { + fn from(e: Error) -> Self { + io::Error::new(io::ErrorKind::Other, e) + } +} + +struct VhostUserFsBackend<FS> +where + FS: FileSystem + Send + Sync, +{ + server: Arc<Server<Arc<FS>>>, + event_idx: bool, + guest_mem: GuestMemoryAtomic<GuestMemoryMmap>, + cache_req: Option<SlaveFsCacheReq>, +} + +impl<FS> VhostUserFsBackend<FS> +where + FS: FileSystem + Send + Sync, +{ + fn process_queue(&mut self, vring: &mut MutexGuard<VringState>) -> std::io::Result<bool> { + let mut used_descs = false; + + while let Some(desc_chain) = vring + .get_queue_mut() + .pop_descriptor_chain(self.guest_mem.memory()) + { + let memory = desc_chain.memory(); + let reader = Reader::from_descriptor_chain(memory, desc_chain.clone()) + .map_err(|_| Error::InvlaidDescriptorChain)?; + let writer = VirtioFsWriter::new(memory, desc_chain.clone()) + .map_err(|_| Error::InvlaidDescriptorChain)?; + + self.server + .handle_message( + reader, + writer.into(), + self.cache_req + .as_mut() + .map(|req| req as &mut dyn FsCacheReqHandler), + None, + ) + .map_err(Error::HandleRequests)?; + + // TODO: Is len 0 correct? + if let Err(error) = vring + .get_queue_mut() + .add_used(memory, desc_chain.head_index(), 0) + { + error!(?error, "failed to add desc back to ring"); + } + + // TODO: What happens if we error out before here? + used_descs = true; + } + + let needs_notification = if self.event_idx { + match vring + .get_queue_mut() + .needs_notification(self.guest_mem.memory().deref()) + { + Ok(needs_notification) => needs_notification, + Err(error) => { + error!(?error, "failed to check if queue needs notification"); + true + } + } + } else { + true + }; + + if needs_notification { + if let Err(error) = vring.signal_used_queue() { + error!(?error, "failed to signal used queue"); + } + } + + Ok(used_descs) + } +} + +impl<FS> VhostUserBackendMut<VringMutex> for VhostUserFsBackend<FS> +where + FS: FileSystem + Send + Sync, +{ + fn num_queues(&self) -> usize { + NUM_QUEUES + } + + fn max_queue_size(&self) -> usize { + QUEUE_SIZE + } + + fn features(&self) -> u64 { + 1 << VIRTIO_F_VERSION_1 + | 1 << VIRTIO_RING_F_INDIRECT_DESC + | 1 << VIRTIO_RING_F_EVENT_IDX + | VhostUserVirtioFeatures::PROTOCOL_FEATURES.bits() + } + + fn protocol_features(&self) -> VhostUserProtocolFeatures { + VhostUserProtocolFeatures::MQ | VhostUserProtocolFeatures::SLAVE_REQ + } + + fn set_event_idx(&mut self, enabled: bool) { + self.event_idx = enabled; + } + + fn update_memory(&mut self, _mem: GuestMemoryAtomic<GuestMemoryMmap>) -> std::io::Result<()> { + // This is what most the vhost user implementations do... + Ok(()) + } + + fn set_slave_req_fd(&mut self, cache_req: SlaveFsCacheReq) { + self.cache_req = Some(cache_req); + } + + fn handle_event( + &mut self, + device_event: u16, + evset: vmm_sys_util::epoll::EventSet, + vrings: &[VringMutex], + _thread_id: usize, + ) -> std::io::Result<bool> { + if evset != EventSet::IN { + return Err(Error::HandleEventNotEpollIn.into()); + } + + let mut queue = match device_event { + // High priority queue + 0 => vrings[0].get_mut(), + // Regurlar priority queue + 1 => vrings[1].get_mut(), + _ => { + return Err(Error::HandleEventUnknownEvent.into()); + } + }; + + if self.event_idx { + loop { + queue + .get_queue_mut() + .enable_notification(self.guest_mem.memory().deref()) + .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?; + if !self.process_queue(&mut queue)? { + break; + } + } + } else { + self.process_queue(&mut queue)?; + } + + Ok(false) + } +} + +pub fn start_virtiofs_daemon<FS, P>(fs: FS, socket: P) -> io::Result<()> +where + FS: FileSystem + Send + Sync + 'static, + P: AsRef<Path>, +{ + let guest_mem = GuestMemoryAtomic::new(GuestMemoryMmap::new()); + + let server = Arc::new(fuse_backend_rs::api::server::Server::new(Arc::new(fs))); + + let backend = Arc::new(RwLock::new(VhostUserFsBackend { + server, + guest_mem: guest_mem.clone(), + event_idx: false, + cache_req: None, + })); + + let listener = Listener::new(socket, true).unwrap(); + + let mut fs_daemon = + VhostUserDaemon::new(String::from("vhost-user-fs-tvix-store"), backend, guest_mem) + .map_err(|_| Error::NewDaemon)?; + + fs_daemon.start(listener).map_err(|_| Error::StartDaemon)?; + + fs_daemon.wait().map_err(|_| Error::WaitDaemon)?; + + Ok(()) +} |