drm,i915: Introduce drm_malloc_gfp()

I have instances where I want to use drm_malloc_ab() but with a custom
gfp mask. And with those, where I want a temporary allocation, I want to
try a high-order kmalloc() before using a vmalloc().

So refactor my usage into drm_malloc_gfp().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: dri-devel@lists.freedesktop.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1460113874-17366-6-git-send-email-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c
index 54088a4..d597414 100644
--- a/drivers/gpu/drm/i915/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/i915_gem_userptr.c
@@ -494,10 +494,7 @@
 	ret = -ENOMEM;
 	pinned = 0;
 
-	pvec = kmalloc(npages*sizeof(struct page *),
-		       GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
-	if (pvec == NULL)
-		pvec = drm_malloc_ab(npages, sizeof(struct page *));
+	pvec = drm_malloc_gfp(npages, sizeof(struct page *), GFP_TEMPORARY);
 	if (pvec != NULL) {
 		struct mm_struct *mm = obj->userptr.mm->mm;
 
@@ -634,14 +631,11 @@
 	pvec = NULL;
 	pinned = 0;
 	if (obj->userptr.mm->mm == current->mm) {
-		pvec = kmalloc(num_pages*sizeof(struct page *),
-			       GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY);
+		pvec = drm_malloc_gfp(num_pages, sizeof(struct page *),
+				      GFP_TEMPORARY);
 		if (pvec == NULL) {
-			pvec = drm_malloc_ab(num_pages, sizeof(struct page *));
-			if (pvec == NULL) {
-				__i915_gem_userptr_set_active(obj, false);
-				return -ENOMEM;
-			}
+			__i915_gem_userptr_set_active(obj, false);
+			return -ENOMEM;
 		}
 
 		pinned = __get_user_pages_fast(obj->userptr.ptr, num_pages,