From 741cbbae0768b828be2d48331eb371a4f08bbea8 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Sat, 3 Aug 2019 08:14:25 +0200
Subject: [PATCH] KVM: remove kvm_arch_has_vcpu_debugfs()

There is no need for this function as all arches have to implement
kvm_arch_create_vcpu_debugfs() no matter what.  A #define symbol
let us actually simplify the code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/mips/kvm/mips.c            | 10 ----------
 arch/powerpc/kvm/powerpc.c      | 10 ----------
 arch/s390/kvm/kvm-s390.c        | 10 ----------
 arch/x86/include/asm/kvm_host.h |  2 ++
 arch/x86/kvm/debugfs.c          |  5 -----
 include/linux/kvm_host.h        |  3 ++-
 virt/kvm/arm/arm.c              |  5 -----
 virt/kvm/kvm_main.c             |  5 ++---
 8 files changed, 6 insertions(+), 44 deletions(-)

diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 2cfe839f0b3a..1109924560d8 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -150,16 +150,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	return 0;
 }
 
-bool kvm_arch_has_vcpu_debugfs(void)
-{
-	return false;
-}
-
-int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
-{
-	return 0;
-}
-
 void kvm_mips_free_vcpus(struct kvm *kvm)
 {
 	unsigned int i;
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 3e34d5fa6708..3e566c2e6066 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -457,16 +457,6 @@ err_out:
 	return -EINVAL;
 }
 
-bool kvm_arch_has_vcpu_debugfs(void)
-{
-	return false;
-}
-
-int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
-{
-	return 0;
-}
-
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
 	unsigned int i;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 3f520cd837fb..f329dcb3f44c 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2516,16 +2516,6 @@ out_err:
 	return rc;
 }
 
-bool kvm_arch_has_vcpu_debugfs(void)
-{
-	return false;
-}
-
-int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
-{
-	return 0;
-}
-
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
 	VCPU_EVENT(vcpu, 3, "%s", "free cpu");
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index fc046ca89d32..e92725b2a46f 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -35,6 +35,8 @@
 #include <asm/kvm_vcpu_regs.h>
 #include <asm/hyperv-tlfs.h>
 
+#define __KVM_HAVE_ARCH_VCPU_DEBUGFS
+
 #define KVM_MAX_VCPUS 288
 #define KVM_SOFT_MAX_VCPUS 240
 #define KVM_MAX_VCPU_ID 1023
diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
index 329361b69d5e..9bd93e0d5f63 100644
--- a/arch/x86/kvm/debugfs.c
+++ b/arch/x86/kvm/debugfs.c
@@ -8,11 +8,6 @@
 #include <linux/debugfs.h>
 #include "lapic.h"
 
-bool kvm_arch_has_vcpu_debugfs(void)
-{
-	return true;
-}
-
 static int vcpu_get_timer_advance_ns(void *data, u64 *val)
 {
 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 9e4c2bb90297..8d34db3c8bc6 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -861,8 +861,9 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu);
 
-bool kvm_arch_has_vcpu_debugfs(void);
+#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu);
+#endif
 
 int kvm_arch_hardware_enable(void);
 void kvm_arch_hardware_disable(void);
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index acc43242a310..13f5a1aa6d79 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -144,11 +144,6 @@ out_fail_alloc:
 	return ret;
 }
 
-bool kvm_arch_has_vcpu_debugfs(void)
-{
-	return false;
-}
-
 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
 {
 	return 0;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1f05aeb9da27..4afb1a234018 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2617,12 +2617,10 @@ static int create_vcpu_fd(struct kvm_vcpu *vcpu)
 
 static int kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
 {
+#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
 	char dir_name[ITOA_MAX_LEN * 2];
 	int ret;
 
-	if (!kvm_arch_has_vcpu_debugfs())
-		return 0;
-
 	if (!debugfs_initialized())
 		return 0;
 
@@ -2637,6 +2635,7 @@ static int kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
 		debugfs_remove_recursive(vcpu->debugfs_dentry);
 		return ret;
 	}
+#endif
 
 	return 0;
 }