On Mon, 02/24 11:39, Paolo Bonzini wrote: > Il 24/02/2014 02:01, Fam Zheng ha scritto: > > > >I would do this in qcow2: > > > > 1. In qcow2_co_writev, allocate cluster regardless of if data is zero or > > not. > > 2. If data is zero, set QCOW2_OFLAG_ZERO in L2. > > This is (or should be) bdrv_co_write_zeroes without BDRV_REQ_MAY_UNMAP.
But IIUC bdrv_co_write_zeroes without BDRV_REQ_MAY_UNMAP doesn't require cluster allocation if it's allocated yet, which is a bit different. Fam
