KVM: x86/mmu: Make is_nx_huge_page_enabled an inline function

Function 'is_nx_huge_page_enabled' is called only by kvm/mmu, so make
it as inline fucntion and remove the unnecessary declaration.

Cc: Ben Gardon <bgardon@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Message-Id: <1622102271-63107-1-git-send-email-zhangshaokun@hisilicon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu/mmu.c

@@ -55,7 +55,7 @@
 
 extern bool itlb_multihit_kvm_mitigation;
 
-static int __read_mostly nx_huge_pages = -1;
+int __read_mostly nx_huge_pages = -1;
 #ifdef CONFIG_PREEMPT_RT
 /* Recovery can cause latency spikes, disable it for PREEMPT_RT.  */
 static uint __read_mostly nx_huge_pages_recovery_ratio = 0;
@@ -208,11 +208,6 @@ void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
 	kvm_flush_remote_tlbs_with_range(kvm, &range);
 }
 
-bool is_nx_huge_page_enabled(void)
-{
-	return READ_ONCE(nx_huge_pages);
-}
-
 static void mark_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 gfn,
 			   unsigned int access)
 {

arch/x86/kvm/mmu/mmu_internal.h

@@ -116,7 +116,12 @@ static inline bool kvm_vcpu_ad_need_write_protect(struct kvm_vcpu *vcpu)
 	       kvm_x86_ops.cpu_dirty_log_size;
 }
 
-bool is_nx_huge_page_enabled(void);
+extern int nx_huge_pages;
+static inline bool is_nx_huge_page_enabled(void)
+{
+	return READ_ONCE(nx_huge_pages);
+}
+
 bool mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
 			    bool can_unsync);
 
@@ -158,8 +163,6 @@ int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn,
 void disallowed_hugepage_adjust(u64 spte, gfn_t gfn, int cur_level,
 				kvm_pfn_t *pfnp, int *goal_levelp);
 
-bool is_nx_huge_page_enabled(void);
-
 void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc);
 
 void account_huge_nx_page(struct kvm *kvm, struct kvm_mmu_page *sp);