b333z/zfs — comment on commit 2d69db27f9f459d4205050899589893dee4564bc
File:  line 0
By behlendorf:

The `zfs destroy` path is short, just zfs_ioc_destroy->zfs_unmount_snap(). But you raise an interesting point about the other various error cases. It got me wondering why this isn't an issue on OpenSolaris. It turns out it's because their dounmount() hook already takes a reference to the mounted vfs namespace so ENOENT is impossible. The Linux version I reworked just takes a path. So we should really do is rework zfs_unmount_snap() to provide the same behavior and just treat ENOENT as success like Solaris.