KVM: arm64: Move guest_owns_fp_regs() to increase its scope

guest_owns_fp_regs() will be used to check fpsimd state ownership
across kvm/arm64. Therefore, move it to kvm_host.h to widen its
scope.

Moreover, the host state is not per-vcpu anymore, the vcpu
parameter isn't used, so remove it as well.

No functional change intended.

Signed-off-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-3-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: Fuad Tabba

arch/arm64/include/asm/kvm_host.h

@@ -1207,6 +1207,12 @@ DECLARE_KVM_HYP_PER_CPU(struct kvm_host_data, kvm_host_data);
 	 &this_cpu_ptr_hyp_sym(kvm_host_data)->f)
 #endif
 
+/* Check whether the FP regs are owned by the guest */
+static inline bool guest_owns_fp_regs(void)
+{
+	return *host_data_ptr(fp_owner) == FP_STATE_GUEST_OWNED;
+}
+
 static inline void kvm_init_host_cpu_context(struct kvm_cpu_context *cpu_ctxt)
 {
 	/* The host's MPIDR is immutable, so let's set it up at boot time */

arch/arm64/kvm/hyp/include/hyp/switch.h

@@ -39,12 +39,6 @@ struct kvm_exception_table_entry {
 extern struct kvm_exception_table_entry __start___kvm_ex_table;
 extern struct kvm_exception_table_entry __stop___kvm_ex_table;
 
-/* Check whether the FP regs are owned by the guest */
-static inline bool guest_owns_fp_regs(struct kvm_vcpu *vcpu)
-{
-	return *host_data_ptr(fp_owner) == FP_STATE_GUEST_OWNED;
-}
-
 /* Save the 32-bit only FPSIMD system register state */
 static inline void __fpsimd_save_fpexc32(struct kvm_vcpu *vcpu)
 {

arch/arm64/kvm/hyp/nvhe/switch.c

@@ -53,7 +53,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 			val |= CPTR_EL2_TSM;
 	}
 
-	if (!guest_owns_fp_regs(vcpu)) {
+	if (!guest_owns_fp_regs()) {
 		if (has_hvhe())
 			val &= ~(CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN |
 				 CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN);

arch/arm64/kvm/hyp/vhe/switch.c

@@ -75,7 +75,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 
 	val |= CPTR_EL2_TAM;
 
-	if (guest_owns_fp_regs(vcpu)) {
+	if (guest_owns_fp_regs()) {
 		if (vcpu_has_sve(vcpu))
 			val |= CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN;
 	} else {