pub fn parse_qgroupid(s: &str) -> Result<u64>Expand description
Parse a qgroup ID string of the form "<level>/<subvolid>" into a packed u64.
The packed form is (level as u64) << 48 | subvolid.
Example: "0/5" → 5, "1/256" → 0x0001_0000_0000_0100.