tree 26f269cd503a1fcc0bc9f7eb88be687c95aa8725
parent dbc0da396a7913a896ef14f5134db7fa2e62be4b
author Alistair Delva <adelva@google.com> 1589499303 -0700
committer Alistair Delva <adelva@google.com> 1589587244 -0700

Expand virtio_block check to other virtual devices

The Android Emulator isn't the only virtual device the virtio-block
detection code is useful for, and those platforms might not set any
discriminating properties to indicate that they are virtual.

Rework the virtio-block major detection to use /proc/devices instead
of hardcoding the assumption that any virtual platform can have
virtio-block at any experimental major; the new code permits only the
exact experimental major assigned to virtio-block.

The new code runs everywhere, but it will only run once and could be
expanded later to detect dynamic or experimental majors.

Bug: 156286088
Change-Id: Ieae805d08fddd0124a397636f04d99194a9ef7e5