passthrough: don't flood log with unnecessary error logs

We now take use from_name_at() to query mnt id in do_lookup() and other
places, and if the underlying filesystem doesn't support file handle,
from_name_at() will print an error message and return ENOTSUPP. And we
ignore this error in open_file_or_handle(). But the error message will
flood the log.

Similarly, we print an error message when open_file_or_handle() returns
an error in do_lookup(), so we flood the log every time we lookup a
non-existent file, and it's totall fine to return ENOENT to fuse
client, it's not a fuse internal error.

For example:

"from_name_at failed error Os { code: 95, kind: Other, message: \"Not supported\" }","level":"ERRO"
"fuse: do_lookup: failed to get file or handle: Os { code: 2, kind: NotFound, message: \"No such file or directory\" }","level":"ERRO"

So let's stop flooding the log.

Signed-off-by: Eryu Guan <[email protected]>

Author: Edsoft333

src/passthrough/file_handle.rs

@@ -130,7 +130,6 @@ impl FileHandle {
             })
         } else {
             let e = io::Error::last_os_error();
-            error!("from_name_at failed error {:?}", e);
             Err(e)
         }
     }
@@ -151,7 +150,10 @@ impl FileHandle {
     where
         F: FnOnce(RawFd, libc::c_int) -> io::Result<File>,
     {
-        let handle = Self::from_name_at(dir_fd, path)?;
+        let handle = Self::from_name_at(dir_fd, path).map_err(|e| {
+            error!("from_name_at failed error {:?}", e);
+            e
+        })?;
 
         mount_fds.ensure_mount_point(handle.mnt_id, dir_fd, path, reopen_dir)?;
 

src/passthrough/mod.rs

@@ -754,11 +754,7 @@ impl<D: AsyncDrive, S: BitmapSlice + Send + Sync> PassthroughFs<D, S> {
             name,
             &self.mount_fds,
             |fd, flags| Self::open_proc_file(&self.proc, fd, flags),
-        )
-        .map_err(|e| {
-            error!("fuse: do_lookup: failed to get file or handle: {:?}", e);
-            e
-        })?;
+        )?;
 
         let mut found = None;
         'search: loop {