diff --git a/opensubdiv/osd/cpuGLVertexBuffer.cpp b/opensubdiv/osd/cpuGLVertexBuffer.cpp
index 1a7b8f27..b959727d 100644
--- a/opensubdiv/osd/cpuGLVertexBuffer.cpp
+++ b/opensubdiv/osd/cpuGLVertexBuffer.cpp
@@ -85,8 +85,7 @@ OsdCpuGLVertexBuffer::OsdCpuGLVertexBuffer(int numElements, int numVertices)
 
 OsdCpuGLVertexBuffer::~OsdCpuGLVertexBuffer() {
 
-    if (_cpuBuffer)
-        delete[] _cpuBuffer;
+    delete[] _cpuBuffer;
     glDeleteBuffers(1, &_vbo);
 }
 
@@ -102,8 +101,7 @@ OsdCpuGLVertexBuffer::Create(int numElements, int numVertices) {
 void
 OsdCpuGLVertexBuffer::UpdateData(const float *src, int numVertices) {
 
-    map();
-    memcpy(_cpuBuffer, src, GetNumElements() * numVertices * sizeof(float));
+    memcpy(_cpuBuffer, src, _numElements * numVertices * sizeof(float));
 }
 
 int
@@ -120,20 +118,25 @@ OsdCpuGLVertexBuffer::GetNumVertices() const {
 
 float*
 OsdCpuGLVertexBuffer::BindCpuBuffer() {
-
-    map();
     return _cpuBuffer;
 }
 
 GLuint
 OsdCpuGLVertexBuffer::BindVBO() {
+    int size = _numElements * _numVertices * sizeof(float);
+    GLint prev = 0;
+    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &prev);
+
+    glBindBuffer(GL_ARRAY_BUFFER, _vbo);
+    glBufferData(GL_ARRAY_BUFFER, size, _cpuBuffer, GL_STATIC_DRAW);
+    glBindBuffer(GL_ARRAY_BUFFER, prev);
 
-    unmap();
     return _vbo;
 }
 
 bool
 OsdCpuGLVertexBuffer::allocate() {
+    _cpuBuffer = new float[_numElements * _numVertices];
     int size = _numElements * _numVertices * sizeof(float);
     GLint prev = 0;
 
@@ -147,39 +150,6 @@ OsdCpuGLVertexBuffer::allocate() {
     return false;
 }
 
-void
-OsdCpuGLVertexBuffer::map() {
-
-    if (_cpuBuffer) return;
-
-    int size = _numElements * _numVertices;
-    GLint prev = 0;
-    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &prev);
-
-    _cpuBuffer = new float[size];
-#if defined(GL_VERSION_2_1)
-    glBindBuffer(GL_ARRAY_BUFFER, _vbo);
-    glGetBufferSubData(GL_ARRAY_BUFFER, 0, size * sizeof(float), _cpuBuffer);
-    glBindBuffer(GL_ARRAY_BUFFER, prev);
-#endif
-}
-
-void
-OsdCpuGLVertexBuffer::unmap() {
-
-    if (_cpuBuffer == NULL) return;
-    int size = _numElements * _numVertices * sizeof(float);
-    GLint prev = 0;
-    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &prev);
-
-    glBindBuffer(GL_ARRAY_BUFFER, _vbo);
-    glBufferData(GL_ARRAY_BUFFER, size, _cpuBuffer, GL_STATIC_DRAW);
-    glBindBuffer(GL_ARRAY_BUFFER, prev);
-
-    delete[] _cpuBuffer;
-    _cpuBuffer = NULL;
-}
-
 }  // end namespace OPENSUBDIV_VERSION
 }  // end namespace OpenSubdiv
 
diff --git a/opensubdiv/osd/cpuGLVertexBuffer.h b/opensubdiv/osd/cpuGLVertexBuffer.h
index 394defd7..75b2925f 100644
--- a/opensubdiv/osd/cpuGLVertexBuffer.h
+++ b/opensubdiv/osd/cpuGLVertexBuffer.h
@@ -117,12 +117,6 @@ protected:
     /// Allocates VBO for this buffer. Returns true if success.
     bool allocate();
 
-    /// Acquires cpu memory buffer from GL.
-    void map();
-
-    /// Releases cpu memory and copy them back to GL.
-    void unmap();
-
 private:
     int _numElements;
     int _numVertices;