1 files changed, 88 insertions, 0 deletions
diff --git a/src/fuse/ops/global.rs b/src/fuse/ops/global.rs
new file mode 100644
index 0000000..e2ecd7b
--- /dev/null
+++ b/src/fuse/ops/global.rs
@@ -0,0 +1,88 @@
+use crate::{proto, util::page_size};
+use crate::fuse::{io::FsInfo, private_trait::Sealed, Done, Operation, Reply};
+
+pub enum Init {}
+pub enum Statfs {}
+
+pub struct InitState {
+    pub(crate) kernel_flags: proto::InitFlags,
+    pub(crate) buffer_pages: usize,
+}
+
+impl Sealed for Init {}
+impl Sealed for Statfs {}
+
+impl<'o> Operation<'o> for Init {
+    type RequestBody = &'o proto::InitIn;
+    type ReplyTail = InitState;
+}
+
+impl<'o> Operation<'o> for Statfs {
+    type RequestBody = ();
+    type ReplyTail = ();
+}
+
+impl<'o> Reply<'o, Init> {
+    pub fn ok(self) -> Done<'o> {
+        let InitState {
+            kernel_flags,
+            buffer_pages,
+        } = self.tail;
+
+        let flags = {
+            use proto::InitFlags;
+
+            //TODO: Conditions for these feature flags
+            // - Locks
+            // - ASYNC_DIO
+            // - WRITEBACK_CACHE
+            // - NO_OPEN_SUPPORT
+            // - HANDLE_KILLPRIV
+            // - POSIX_ACL
+            // - NO_OPENDIR_SUPPORT
+            // - EXPLICIT_INVAL_DATA
+
+            let supported = InitFlags::ASYNC_READ
+                | InitFlags::FILE_OPS
+                | InitFlags::ATOMIC_O_TRUNC
+                | InitFlags::EXPORT_SUPPORT
+                | InitFlags::BIG_WRITES
+                | InitFlags::HAS_IOCTL_DIR
+                | InitFlags::AUTO_INVAL_DATA
+                | InitFlags::DO_READDIRPLUS
+                | InitFlags::READDIRPLUS_AUTO
+                | InitFlags::PARALLEL_DIROPS
+                | InitFlags::ABORT_ERROR
+                | InitFlags::MAX_PAGES
+                | InitFlags::CACHE_SYMLINKS;
+
+            kernel_flags & supported
+        };
+
+        let buffer_size = page_size() * buffer_pages;
+
+        // See fs/fuse/dev.c in the kernel source tree for details about max_write
+        let max_write = buffer_size - std::mem::size_of::<(proto::InHeader, proto::WriteIn)>();
+
+        self.single(&proto::InitOut {
+            major: proto::MAJOR_VERSION,
+            minor: proto::TARGET_MINOR_VERSION,
+            max_readahead: 0, //TODO
+            flags: flags.bits(),
+            max_background: 0,       //TODO
+            congestion_threshold: 0, //TODO
+            max_write: max_write.try_into().unwrap(),
+            time_gran: 1, //TODO
+            max_pages: buffer_pages.try_into().unwrap(),
+            padding: Default::default(),
+            unused: Default::default(),
+        })
+    }
+}
+
+impl<'o> Reply<'o, Statfs> {
+    /// Replies with filesystem statistics.
+    pub fn info(self, statfs: &FsInfo) -> Done<'o> {
+        self.single(&proto::StatfsOut::from(*statfs))
+    }
+}