KVM: arm64: selftests: Add guest support to get the vcpuid

At times, such as when in the interrupt handler, the guest wants
to get the vcpuid that it's running on to pull the per-cpu private
data. As a result, introduce guest_get_vcpuid() that returns the
vcpuid of the calling vcpu. The interface is architecture
independent, but defined only for arm64 as of now.

Suggested-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211007233439.1826892-11-rananta@google.com

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 010b59b13917646c51b70752b5fc45669e9b0b80..bcf05f5381ede335ea787260fbd79f9acdb03ec2 100644 (file)
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -400,4 +400,6 @@ uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc);
 int vm_get_stats_fd(struct kvm_vm *vm);
 int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid);
 
+uint32_t guest_get_vcpuid(void);
+
 #endif /* SELFTEST_KVM_UTIL_H */

diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c
index 34f6bd47661f8a93c56f93da5266cc3e05572e85..b4eeeafd2a70bbf5c0499b284267e633c7a7e498 100644 (file)
--- a/tools/testing/selftests/kvm/lib/aarch64/processor.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c
@@ -277,6 +277,7 @@ void aarch64_vcpu_setup(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_vcpu_init
        set_reg(vm, vcpuid, KVM_ARM64_SYS_REG(SYS_TCR_EL1), tcr_el1);
        set_reg(vm, vcpuid, KVM_ARM64_SYS_REG(SYS_MAIR_EL1), DEFAULT_MAIR_EL1);
        set_reg(vm, vcpuid, KVM_ARM64_SYS_REG(SYS_TTBR0_EL1), vm->pgd);
+       set_reg(vm, vcpuid, KVM_ARM64_SYS_REG(SYS_TPIDR_EL1), vcpuid);
 }
 
 void vcpu_dump(FILE *stream, struct kvm_vm *vm, uint32_t vcpuid, uint8_t indent)
@@ -426,3 +427,8 @@ void vm_install_exception_handler(struct kvm_vm *vm, int vector,
        assert(vector < VECTOR_NUM);
        handlers->exception_handlers[vector][0] = handler;
 }
+
+uint32_t guest_get_vcpuid(void)
+{
+       return read_sysreg(tpidr_el1);
+}