chore(tvix): move store/fs to castore/fs r/7256

With the recent introduction of the RootNodes trait, there's nothing in
the fs module pulling in tvix-store dependencies, so it can live in
tvix-castore.

This allows other crates to make use of TvixStoreFS, without having to
pull in tvix-store.

For example, a tvix-build using a fuse mountpoint at /nix/store doesn't
need a PathInfoService to hold the root nodes that should be present,
but just a list.

tvix-store now has a pathinfoservice/fs module, which contains the
necessary glue logic to implement the RootNodes trait for a
PathInfoService.

To satisfy Rust orphan rules for trait implementations, we had to add a
small wrapper struct. It's mostly hidden away by the make_fs helper
function returning a TvixStoreFs.

It can't be entirely private, as its still leaking into the concrete
type of TvixStoreFS.

tvix-store still has `fuse` and `virtiofs` features, but they now simply
enable these features in the `tvix-castore` crate they depend on.

The tests for the fuse functionality stay in tvix-store for now, as
they populate the root nodes through a PathInfoService.

Once above mentioned "list of root nodes" implementation exists, we
might want to shuffle this around one more time.

Fixes b/341.

Change-Id: I989f664827a5a361b23b34368d242d10c157c756
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10378
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>

1 files changed, 0 insertions, 53 deletions

diff --git a/tvix/store/src/fs/file_attr.rs b/tvix/store/src/fs/file_attr.rs
deleted file mode 100644
index ad41f036a253..000000000000
--- a/tvix/store/src/fs/file_attr.rs
+++ /dev/null
@@ -1,53 +0,0 @@
-#![allow(clippy::unnecessary_cast)] // libc::S_IFDIR is u32 on Linux and u16 on MacOS
-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()
-    }
-}