Jason Wang <jasow...@redhat.com> wrote: > We need to keep DIR register unchanged across migration, but currently it > depends on the media_changed flags from block layer. Since we do not > save/restore it and the bdrv_open() called in dest node may set the > media_changed flag when trying to open floppy image, guest driver may think > the > floppy have changed after migration. To fix this, a new filed media_changed in > FDrive strcutre was introduced in order to save and restore the it from block > layer through pre_save/post_load callbacks. > > Signed-off-by: Jason Wang <jasow...@redhat.com> > --- > > Changed from V3: > According to Juan's suggestions, back to v2 and just add the checking for > media_changed "changed" in .needed. > Do not fail the migration when src have a drive but dest does not, we can > treat > it as user ejected the floppy. > > Changed from V2: > According to Paolo's suggestions, a default_migration_media_changed property > was > added to avoid saving subsections as much as possible. Its was set > media_changed > in pre_load callback and then we can avoid the saving when it was equal to the > media_changed when migrating the FDrive. Behaviors of elder machine types are > also kept through compat_props. > > Changed from V1: > Check the drive->bs during post_load. > > hw/fdc.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++- > 1 files changed, 50 insertions(+), 1 deletions(-) >
Reviewed-by: Juan Quintela <quint...@redhat.com> This solution is way less invasive that v3, and achieves exactly the same compatibility.
