Jason Wang<address@hidden> 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<address@hidden>
---
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<address@hidden>
This solution is way less invasive that v3, and achieves exactly the
same compatibility.