x86/fpu: create FPU init and destroy functions

Extract FPU initialization and destroy code into two functions. These
functions handle memory allocation/deallocation for FPU context.

Signed-off-by: Wei Huang <wei.huang2@amd.com>

3 files changed, 47 insertions, 21 deletions

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 56031c3db4..538d497306 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -420,20 +420,8 @@ int vcpu_initialise(struct vcpu *v)
 
     v->arch.perdomain_ptes = perdomain_ptes(d, v);
 
-    if ( (rc = xstate_alloc_save_area(v)) != 0 )
+    if ( (rc = vcpu_init_fpu(v)) != 0 )
         return rc;
-    if ( v->arch.xsave_area )
-        v->arch.fpu_ctxt = &v->arch.xsave_area->fpu_sse;
-    else if ( !is_idle_domain(d) )
-    {
-        v->arch.fpu_ctxt = _xmalloc(sizeof(v->arch.xsave_area->fpu_sse), 16);
-        if ( !v->arch.fpu_ctxt )
-        {
-            rc = -ENOMEM;
-            goto done;
-        }
-        memset(v->arch.fpu_ctxt, 0, sizeof(v->arch.xsave_area->fpu_sse));
-    }
 
     if ( is_hvm_domain(d) )
     {
@@ -485,10 +473,8 @@ int vcpu_initialise(struct vcpu *v)
  done:
     if ( rc )
     {
-        if ( v->arch.xsave_area )
-            xstate_free_save_area(v);
-        else
-            xfree(v->arch.fpu_ctxt);
+        vcpu_destroy_fpu(v);
+
         if ( !is_hvm_domain(d) && standalone_trap_ctxt(v) )
             free_xenheap_page(v->arch.pv_vcpu.trap_ctxt);
     }
@@ -501,10 +487,7 @@ void vcpu_destroy(struct vcpu *v)
     if ( is_pv_32on64_vcpu(v) )
         release_compat_l4(v);
 
-    if ( v->arch.xsave_area )
-        xstate_free_save_area(v);
-    else
-        xfree(v->arch.fpu_ctxt);
+    vcpu_destroy_fpu(v);
 
     if ( is_hvm_vcpu(v) )
         hvm_vcpu_destroy(v);
diff --git a/xen/arch/x86/i387.c b/xen/arch/x86/i387.c
index c04eadc721..255e1e51dd 100644
--- a/xen/arch/x86/i387.c
+++ b/xen/arch/x86/i387.c
@@ -184,6 +184,47 @@ static void restore_fpu(struct vcpu *v)
     }
 }
 
+/*******************************/
+/*       VCPU FPU Functions    */
+/*******************************/
+/* Initialize FPU's context save area */
+int vcpu_init_fpu(struct vcpu *v)
+{
+    int rc = 0;
+    
+    /* Idle domain doesn't have FPU state allocated */
+    if ( is_idle_vcpu(v) )
+        goto done;
+
+    if ( (rc = xstate_alloc_save_area(v)) != 0 )
+        return rc;
+
+    if ( v->arch.xsave_area )
+        v->arch.fpu_ctxt = &v->arch.xsave_area->fpu_sse;
+    else
+    {
+        v->arch.fpu_ctxt = _xmalloc(sizeof(v->arch.xsave_area->fpu_sse), 16);
+        if ( !v->arch.fpu_ctxt )
+        {
+            rc = -ENOMEM;
+            goto done;
+        }
+        memset(v->arch.fpu_ctxt, 0, sizeof(v->arch.xsave_area->fpu_sse));
+    }
+
+done:
+    return rc;
+}
+
+/* Free FPU's context save area */
+void vcpu_destroy_fpu(struct vcpu *v)
+{
+    if ( v->arch.xsave_area )
+        xstate_free_save_area(v);
+    else
+        xfree(v->arch.fpu_ctxt);
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/include/asm-x86/i387.h b/xen/include/asm-x86/i387.h
index f94cdad6f6..f2bd78d680 100644
--- a/xen/include/asm-x86/i387.h
+++ b/xen/include/asm-x86/i387.h
@@ -17,4 +17,6 @@
 void setup_fpu(struct vcpu *v);
 void save_init_fpu(struct vcpu *v);
 
+int vcpu_init_fpu(struct vcpu *v);
+void vcpu_destroy_fpu(struct vcpu *v);
 #endif /* __ASM_I386_I387_H */