Most callers of ram_block_discard_range() want to discard both the
shared and guest_memfd backing. Only kvm_convert_memory() intentionally
discards a single plane during private/shared conversions.
Rename the current implementation to ram_block_discard_shared_range()
and make ram_block_discard_range() a composite that also discards
guest_memfd when present (rb->guest_memfd >= 0). This ensures callers
like virtio-mem, virtio-balloon, hv-balloon, migration.. reclaim
private pages on discard.
Update kvm_convert_memory() to use the plane-specific
ram_block_discard_shared_range() since it only needs to discard
the shared backing when converting to private.
Likewise, after TDVF image copy, use ram_block_discard_shared_range().
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Link: https://lore.kernel.org/r/20260604-rdm5-v5-11-5768e6a0943d@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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