This patchset enables the core of the quorum mechanism.
The num_children reads are compared to get the majority version and if this
version exists more than threshold times the guest won't see the error at all.
If a block is corrupted or if an error occurs during an IO or if the quorum
cannot be established QMP events are used to report to the management.
Use gnutls's SHA-256 to compare versions.
--enable-quorum must be used to enable the feature.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
95c6bff356