ARM: KVM: Keep track of currently running vcpus

When an interrupt occurs for the guest, it is sometimes necessary
to find out which vcpu was running at that point.

Keep track of which vcpu is being run in kvm_arch_vcpu_ioctl_run(),
and allow the data to be retrieved using either:
- kvm_arm_get_running_vcpu(): returns the vcpu running at this point
  on the current CPU. Can only be used in a non-preemptible context.
- kvm_arm_get_running_vcpus(): returns the per-CPU variable holding
  the running vcpus, usable for per-CPU interrupts.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 98b4d1a72923..fc161de21ea2 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -158,4 +158,14 @@ static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
 {
 	return 0;
 }
+
+struct kvm_vcpu *kvm_arm_get_running_vcpu(void);
+struct kvm_vcpu __percpu **kvm_get_running_vcpus(void);
+
+int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices);
+unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu);
+struct kvm_one_reg;
+int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
+int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
+
 #endif /* __ARM_KVM_HOST_H__ */