• Cédric Le Goater's avatar
    KVM: PPC: Book3S HV: XIVE: Replace the 'destroy' method by a 'release' method · 5422e951
    Cédric Le Goater authored
    When a P9 sPAPR VM boots, the CAS negotiation process determines which
    interrupt mode to use (XICS legacy or XIVE native) and invokes a
    machine reset to activate the chosen mode.
    
    We introduce 'release' methods for the XICS-on-XIVE and the XIVE
    native KVM devices which are called when the file descriptor of the
    device is closed after the TIMA and ESB pages have been unmapped.
    They perform the necessary cleanups : clear the vCPU interrupt
    presenters that could be attached and then destroy the device. The
    'release' methods replace the 'destroy' methods as 'destroy' is not
    called anymore once 'release' is. Compatibility with older QEMU is
    nevertheless maintained.
    
    This is not considered as a safe operation as the vCPUs are still
    running and could be referencing the KVM device through their
    presenters. To protect the system from any breakage, the kvmppc_xive
    objects representing both KVM devices are now stored in an array under
    the VM. Allocation is performed on first usage and memory is freed
    only when the VM exits.
    
    [paulus@ozlabs.org - Moved freeing of xive structures to book3s.c,
     put it under #ifdef CONFIG_KVM_XICS.]
    Signed-off-by: default avatarCédric Le Goater <clg@kaod.org>
    Reviewed-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
    Signed-off-by: default avatarPaul Mackerras <paulus@ozlabs.org>
    5422e951
book3s_xive.c 53.8 KB