Am 08.03.2011 14:13, schrieb Stefan Hajnoczi: > On Tue, Mar 8, 2011 at 11:47 AM, Kevin Wolf <kw...@redhat.com> wrote: >> + 20 - 23: cluster_bits >> + Number of bits that are used for addressing an offset >> + within a cluster (1 << cluster_bits is the cluster size) >> + >> + 24 - 31: size >> + Virtual disk size in bytes > > Any constraints on these two fields that should be mentioned?
For the size not that I'm aware of. For cluster_bits qemu restricts it to 512 <= cluster_size <= 2 MB. I think we should add 512 as a lower limit, anything smaller doesn't make sense and steals us bits that we want to use for flags. The 2 MB are more of an implementation limitation. Would you mention it here? The format shouldn't have any problem with larger sizes. Kevin
