[patch 04/12] KVM: move muldiv64 to x86.c, export

[Marcelo Tosatti <mtosatti@redhat.com>]

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This should probably to go lib/

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: kvm/arch/x86/kvm/i8254.c
===================================================================
--- kvm.orig/arch/x86/kvm/i8254.c
+++ kvm/arch/x86/kvm/i8254.c
@@ -45,26 +45,6 @@
 #define RW_STATE_WORD0 3
 #define RW_STATE_WORD1 4
 
-/* Compute with 96 bit intermediate result: (a*b)/c */
-static u64 muldiv64(u64 a, u32 b, u32 c)
-{
-	union {
-		u64 ll;
-		struct {
-			u32 low, high;
-		} l;
-	} u, res;
-	u64 rl, rh;
-
-	u.ll = a;
-	rl = (u64)u.l.low * (u64)b;
-	rh = (u64)u.l.high * (u64)b;
-	rh += (rl >> 32);
-	res.l.high = div64_u64(rh, c);
-	res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c);
-	return res.ll;
-}
-
 static void pit_set_gate(struct kvm *kvm, int channel, u32 val)
 {
 	struct kvm_kpit_channel_state *c =
Index: kvm/arch/x86/kvm/x86.c
===================================================================
--- kvm.orig/arch/x86/kvm/x86.c
+++ kvm/arch/x86/kvm/x86.c
@@ -4116,3 +4116,30 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu
 		smp_call_function_single(ipi_pcpu, vcpu_kick_intr, vcpu, 0, 0);
 	put_cpu();
 }
+
+#ifndef CONFIG_X86_64
+#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
+#else
+#define mod_64(x, y) ((x) % (y))
+#endif
+
+/* Compute with 96 bit intermediate result: (a*b)/c */
+u64 muldiv64(u64 a, u32 b, u32 c)
+{
+	union {
+		u64 ll;
+		struct {
+			u32 low, high;
+		} l;
+	} u, res;
+	u64 rl, rh;
+
+	u.ll = a;
+	rl = (u64)u.l.low * (u64)b;
+	rh = (u64)u.l.high * (u64)b;
+	rh += (rl >> 32);
+	res.l.high = div64_u64(rh, c);
+	res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c);
+	return res.ll;
+}
+EXPORT_SYMBOL(muldiv64);
Index: kvm/include/asm-x86/kvm_host.h
===================================================================
--- kvm.orig/include/asm-x86/kvm_host.h
+++ kvm/include/asm-x86/kvm_host.h
@@ -660,6 +660,8 @@ static inline void kvm_inject_gp(struct 
 	kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
 }
 
+u64 muldiv64(u64, u32, u32);
+
 #define ASM_VMX_VMCLEAR_RAX       ".byte 0x66, 0x0f, 0xc7, 0x30"
 #define ASM_VMX_VMLAUNCH          ".byte 0x0f, 0x01, 0xc2"
 #define ASM_VMX_VMRESUME          ".byte 0x0f, 0x01, 0xc3"

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