Use the IoctlRetInt, IoctlSetInt and IoctlLoopSetStatus64 helper
functions defined in the golang.org/x/sys/unix package instead of
manually wrapping these using a locally defined ioctl function.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
setupLoop()'s Autoclear (LO_FLAGS_AUTOCLEAR) will destruct the
loopback device when all associated file descriptors are closed.
However this behavior didn't work before since setupLoop() was
returning a file name. The looppack device was destructed at
the end of the function when LoopParams had Autoclear = true.
Fixes#4969.
Signed-off-by: Kazuyoshi Kato <katokazu@amazon.com>
If a mount has specified `loop` option, we need to handle it on our
own instead of passing it to the kernel. In such case, create a
loopback device, attach the mount source to it, and mount the loopback
device rather than the mount source.
Signed-off-by: Peng Tao <bergwolf@hyper.sh>
