• James Hogan's avatar
    MIPS: KVM: Add CP0_Count/Compare KVM register access · f8be02da
    James Hogan authored
    Implement KVM_{GET,SET}_ONE_REG ioctl based access to the guest CP0
    Count and Compare registers. These registers are special in that writing
    to them has side effects (adjusting the time until the next timer
    interrupt) and reading of Count depends on the time. Therefore add a
    couple of callbacks so that different implementations (trap & emulate or
    VZ) can implement them differently depending on what the hardware
    provides.
    
    The trap & emulate versions mostly duplicate what happens when a T&E
    guest reads or writes these registers, so it inherits the same
    limitations which can be fixed in later patches.
    Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
    Cc: Paolo Bonzini <pbonzini@redhat.com>
    Cc: Gleb Natapov <gleb@kernel.org>
    Cc: kvm@vger.kernel.org
    Cc: Ralf Baechle <ralf@linux-mips.org>
    Cc: linux-mips@linux-mips.org
    Cc: David Daney <david.daney@cavium.com>
    Cc: Sanjay Lal <sanjayl@kymasys.com>
    Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    f8be02da
kvm_trap_emul.c 13.2 KB