[PATCH v2 0/3] memory: memory_region_is_mapped() cleanups

[David Hildenbrand <david@redhat.com>]

This is the follow-up of [1].

Playing with memory_region_is_mapped(), I realized that memory regions
mapped via an alias behave a little bit "differently", as they don't have
their ->container set.
* memory_region_is_mapped() will never succeed for memory regions mapped
  via an alias
* memory_region_to_address_space(), memory_region_find(),
  memory_region_find_rcu(), memory_region_present() won't work, which seems
  okay, because we don't expect such memory regions getting passed to these
  functions.
* memory_region_to_absolute_addr() will result in a wrong address. As
  the result is only used for tracing, that is tolerable.

Let's cleanup/fix the code and documentation of memory_region_is_mapped()
and change one user that really should be checking something else.

[1] https://lkml.kernel.org/r/20211011174522.14351-1-david@redhat.com

Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: "Philippe Mathieu-Daudé" <philmd@redhat.com>

David Hildenbrand (3):
  machine: Use host_memory_backend_is_mapped() in
    machine_consume_memdev()
  memory: Make memory_region_is_mapped() succeed when mapped via an
    alias
  memory: Update description of memory_region_is_mapped()

 hw/core/machine.c     |  2 +-
 include/exec/memory.h |  4 +++-
 softmmu/memory.c      | 12 +++++++++++-
 3 files changed, 15 insertions(+), 3 deletions(-)

-- 
2.31.1