i915_vma_compare
cmp = i915_vma_compare(pos, vm, view);
cmp = i915_vma_compare(vma, vm, view);
GEM_BUG_ON(!IS_ERR(vma) && i915_vma_compare(vma, vm, view));
if (i915_vma_compare(vma, vm, view)) {
if (i915_vma_compare(vma, vma->vm,