diff options
Diffstat (limited to 'tvix/store/src/fs')
| -rw-r--r-- | tvix/store/src/fs/mod.rs | 198 |
1 files changed, 76 insertions, 122 deletions
diff --git a/tvix/store/src/fs/mod.rs b/tvix/store/src/fs/mod.rs index bec6af705027..c524f5121840 100644 --- a/tvix/store/src/fs/mod.rs +++ b/tvix/store/src/fs/mod.rs @@ -131,6 +131,74 @@ impl TvixStoreFs { store_paths.get(store_path).cloned() } + /// For a given inode, look up the given directory behind it (from + /// self.inode_tracker), and return its children. + /// The inode_tracker MUST know about this inode already, and it MUST point + /// to a [InodeData::Directory]. + /// It is ok if it's a [DirectoryInodeData::Sparse] - in that case, a lookup + /// in self.directory_service is performed, and self.inode_tracker is updated with the + /// [DirectoryInodeData::Populated]. + #[instrument(skip(self), err)] + fn get_directory_children(&self, ino: u64) -> io::Result<(B3Digest, Vec<(u64, Node)>)> { + let data = self.inode_tracker.read().get(ino).unwrap(); + match *data { + // if it's populated already, return children. + InodeData::Directory(DirectoryInodeData::Populated( + ref parent_digest, + ref children, + )) => Ok((parent_digest.clone(), children.clone())), + // if it's sparse, fetch data using fetch_directory_inode_data and insert. + InodeData::Directory(DirectoryInodeData::Sparse(ref parent_digest, _)) => { + let directory_service = self.directory_service.clone(); + let parent_digest = parent_digest.to_owned(); + match self + .tokio_handle + .block_on(self.tokio_handle.spawn(async move { + match directory_service.get(&parent_digest).await? { + // If the Directory can't be found, this is a hole, bail out. + None => { + warn!(directory.digest=%parent_digest, "directory not found"); + Err(Error::StorageError(format!( + "directory {} not found", + parent_digest + ))) + } + Some(directory) => Ok(directory.into()), + } + })) + .unwrap() + { + Err(_e) => Err(io::Error::from_raw_os_error(libc::EIO)), + Ok( + ref data @ InodeData::Directory(DirectoryInodeData::Populated( + ref parent_digest, + _, + )), + ) => { + // update data in [self.inode_tracker] with populated variant. + // we need to round-trip via self.inode_tracker so + // inodes for children are populated. + self.inode_tracker.write().put(data.clone()); + let children = match *self.inode_tracker.read().get(ino).unwrap() { + InodeData::Directory(DirectoryInodeData::Populated( + _, + ref children, + )) => children.to_owned(), + _ => unreachable!(), + }; + Ok((parent_digest.clone(), children)) + } + // we know fetch_directory_inode_data only returns InodeData::Directory(DirectoryInodeData::Populated(..)) + Ok(_) => panic!("unexpected type"), + } + } + // if the parent inode was not a directory, this doesn't make sense + InodeData::Regular(..) | InodeData::Symlink(_) => { + Err(io::Error::from_raw_os_error(libc::ENOTDIR)) + } + } + } + /// 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 @@ -216,8 +284,8 @@ impl TvixStoreFs { } impl FileSystem for TvixStoreFs { - type Inode = u64; type Handle = u64; + type Inode = u64; fn init(&self, _capable: FsOptions) -> io::Result<FsOptions> { Ok(FsOptions::empty()) @@ -276,69 +344,15 @@ impl FileSystem for TvixStoreFs { } }; } - // 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]. - let (parent_digest, children) = { - let parent_data = self.inode_tracker.read().get(parent).unwrap(); - match *parent_data { - // if it's populated already, extract parent_digest and children. - InodeData::Directory(DirectoryInodeData::Populated( - ref parent_digest, - ref children, - )) => (parent_digest.clone(), children.clone()), - // if it's sparse, fetch data using fetch_directory_inode_data and insert. - InodeData::Directory(DirectoryInodeData::Sparse(ref parent_digest, _)) => { - let directory_service = self.directory_service.clone(); - let parent_digest = parent_digest.to_owned(); - match self - .tokio_handle - .block_on(self.tokio_handle.spawn(async move { - fetch_directory_inode_data(directory_service, &parent_digest).await - })) - .unwrap() - { - Ok( - ref data @ InodeData::Directory(DirectoryInodeData::Populated( - ref parent_digest, - _, - )), - ) => { - // update data in [self.inode_tracker] with populated variant. - // we need to round-trip via self.inode_tracker so - // inodes for children are populated. - self.inode_tracker.write().put(data.clone()); - let children = match *self.inode_tracker.read().get(parent).unwrap() { - InodeData::Directory(DirectoryInodeData::Populated( - _, - ref children, - )) => children.to_owned(), - _ => unreachable!(), - }; - (parent_digest.clone(), children) - } - // we know fetch_directory_inode_data only returns InodeData::Directory(DirectoryInodeData::Populated(..)) - Ok(_) => panic!("unexpected type"), - Err(_e) => { - return Err(io::Error::from_raw_os_error(libc::EIO)); - } - } - } - // if the parent inode was not a directory, this doesn't make sense - InodeData::Regular(..) | InodeData::Symlink(_) => { - return Err(io::Error::from_raw_os_error(libc::ENOTDIR)); - } - } - }; + let (parent_digest, children) = self.get_directory_children(parent)?; - // Now it for sure is populated, so we search for that name in the - // list of children and return the FileAttrs. let span = info_span!("lookup", directory.digest = %parent_digest); let _enter = span.enter(); + // Search for that name in the list of children and return the FileAttrs. + // 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]. @@ -440,52 +454,11 @@ impl FileSystem for TvixStoreFs { } } - // lookup the inode data. - let dir_inode_data = { - let inode_tracker = self.inode_tracker.read(); - inode_tracker.get(inode).unwrap() - }; + // lookup the children, or return an error if it's not a directory. + let (parent_digest, children) = self.get_directory_children(inode)?; - let children = match *dir_inode_data { - InodeData::Directory(DirectoryInodeData::Populated(ref _digest, ref children)) => { - children.to_vec() - } - InodeData::Directory(DirectoryInodeData::Sparse(ref directory_digest, _)) => { - match self - .tokio_handle - .block_on(self.tokio_handle.spawn({ - let directory_digest = directory_digest.to_owned(); - let directory_service = self.directory_service.clone(); - async move { - fetch_directory_inode_data(directory_service, &directory_digest).await - } - })) - .unwrap() - { - Ok( - ref new_data @ InodeData::Directory(DirectoryInodeData::Populated( - ref _digest, - ref children, - )), - ) => { - // update data in [self.inode_tracker] with populated variant. - { - let mut inode_tracker = self.inode_tracker.write(); - inode_tracker.put(new_data.clone()); - } - children.to_vec() - } - // we know fetch_directory_inode_data only returns InodeData::Directory(DirectoryInodeData::Populated(..)) - Ok(_) => panic!("unexpected type"), - Err(_e) => { - return Err(io::Error::from_raw_os_error(libc::EIO)); - } - } - } - InodeData::Regular(..) | InodeData::Symlink(..) => { - return Err(io::Error::from_raw_os_error(libc::ENOTDIR)); - } - }; + let span = info_span!("lookup", directory.digest = %parent_digest); + let _enter = span.enter(); 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. @@ -693,22 +666,3 @@ impl FileSystem for TvixStoreFs { } } } - -/// 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. -#[instrument(skip_all, fields(directory.digest = %directory_digest), err)] -async fn fetch_directory_inode_data<DS: DirectoryService + ?Sized>( - directory_service: Arc<DS>, - directory_digest: &B3Digest, -) -> Result<InodeData, Error> { - match directory_service.get(directory_digest).await? { - // If the Directory can't be found, this is a hole, bail out. - None => Err(Error::StorageError(format!( - "directory {} not found", - directory_digest - ))), - Some(directory) => Ok(directory.into()), - } -} |