* Huaicheng Li (lhc...@gmail.com) wrote: > Hi all, > > Please correct me if I’m wrong. > > I made some changes to IDE emulation (add some extra structures to “struct > IDEState") and want to save these info to files when VM shutdowns. So I can > reload these info from files next time when VM starts. According to my > understanding, one IDEState structure is corresponding to one disk for VM and > all available drives are probed/initialised by ide_init2() in hw/ide.c (I > used qemu v0.11) during VM startup. It seemed that IDEState structure are > saved to QEMUFile structure via pci_ide_save(), but I can only trace up to > register_savevm(), where pci_ide_save() is registered as a callback. I can’t > find where exactly this function starts execution or being called. My > questions are:
Version 0.11 is *ancient* - please start with something newer; pci_ide_save was removed 6 years ago. > (1). Does QEMUFile structure represent a running VM instance, through which I > can access the IDE drive (struct IDEState) pointers ? > > (2). When does qemu execute pci_ide_save()? QEMUFile is part of the migration code; it forms a stream of data containing all of the device and RAM State during migration. See savevm.c for what drives this (in migration/savevm.c in modern qemu). Extracting the state of one device from the stream isn't that easy. > (3). How does qemu handle VM shutdown? It seems ACPI event is sent to VM so > guest OS will shutdown in the way like real OS running on real hardware. But > how and where does qemu exactly handle this? I think I need to add my codes > here. I don't know the detail of that; I suggest following the code from qemu_system_powerdown. Why are you trying to save the state during shutdown? Dave > > Any hints, suggestions would be appreciated. Thanks. > > Huaicheng Li -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
