KVM: Create the KVMSlot dirty bitmap on flag changes
Previously we have two places that will create the per KVMSlot dirty
bitmap:
1. When a newly created KVMSlot has dirty logging enabled,
2. When the first log_sync() happens for a memory slot.
The 2nd case is lazy-init, while the 1st case is not (which is a fix
of what the 2nd case missed).
To do explicit initialization of dirty bitmaps, what we're missing is
to create the dirty bitmap when the slot changed from not-dirty-track
to dirty-track. Do that in kvm_slot_update_flags().
With that, we can safely remove the 2nd lazy-init.
This change will be needed for kvm dirty ring because kvm dirty ring
does not use the log_sync() interface at all.
Also move all the pre-checks into kvm_slot_init_dirty_bitmap().
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <
20210506160549.130416-4-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>