KVM: arm64: introduce vcpu->arch.debug_ptr

This introduces a level of indirection for the debug registers. Instead
of using the sys_regs[] directly we store registers in a structure in
the vcpu. The new kvm_arm_reset_debug_ptr() sets the debug ptr to the
guest context.

Because we no longer give the sys_regs offset for the sys_reg_desc->reg
field, but instead the index into a debug-specific struct we need to
add a number of additional trap functions for each register. Also as the
generic generic user-space access code no longer works we have
introduced a new pair of function pointers to the sys_reg_desc structure
to override the generic code when needed.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index d439eb8f3239..e0947b77faaa 100644
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -67,6 +67,15 @@ void kvm_arm_init_debug(void)
 }
 
 /**
+ * kvm_arm_reset_debug_ptr - reset the debug ptr to point to the vcpu state
+ */
+
+void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu)
+{
+	vcpu->arch.debug_ptr = &vcpu->arch.vcpu_debug_state;
+}
+
+/**
  * kvm_arm_setup_debug - set up debug related stuff
  *
  * @vcpu:	the vcpu pointer