The Friday 29 Aug 2014 à 23:45:27 (+0200), Max Reitz wrote : > A refblock entry may have a different size than 16 bits, it may even be > smaller than a byte. Correct the refcount_block_entries calculation
Now if the refblock entry size is smaller than a byte > accordingly. > > Signed-off-by: Max Reitz <mre...@redhat.com> > --- > docs/specs/qcow2.txt | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt > index cfbc8b0..531c478 100644 > --- a/docs/specs/qcow2.txt > +++ b/docs/specs/qcow2.txt > @@ -183,7 +183,7 @@ blocks and are exactly one cluster in size. > Given a offset into the image file, the refcount of its cluster can be > obtained > as follows: > > - refcount_block_entries = (cluster_size / sizeof(uint16_t)) > + refcount_block_entries = (cluster_size / (refcount_bits / 8)) This give a divide by zero error. ^ > > refcount_block_index = (offset / cluster_size) % refcount_block_entries > refcount_table_index = (offset / cluster_size) / refcount_block_entries > -- > 2.1.0 > >
