drm/ttm: use drm calloc large and free large

Now that the drm core can do this, lets just use it, split the code out
so TTM doesn't have to drag all of drmP.h in.

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index a759170..bab6cd8 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -28,13 +28,13 @@
  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
  */
 
-#include <linux/vmalloc.h>
 #include <linux/sched.h>
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
 #include <linux/file.h>
 #include <linux/swap.h>
 #include "drm_cache.h"
+#include "drm_mem_util.h"
 #include "ttm/ttm_module.h"
 #include "ttm/ttm_bo_driver.h"
 #include "ttm/ttm_placement.h"
@@ -43,32 +43,15 @@
 
 /**
  * Allocates storage for pointers to the pages that back the ttm.
- *
- * Uses kmalloc if possible. Otherwise falls back to vmalloc.
  */
 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
 {
-	unsigned long size = ttm->num_pages * sizeof(*ttm->pages);
-	ttm->pages = NULL;
-
-	if (size <= PAGE_SIZE)
-		ttm->pages = kzalloc(size, GFP_KERNEL);
-
-	if (!ttm->pages) {
-		ttm->pages = vmalloc_user(size);
-		if (ttm->pages)
-			ttm->page_flags |= TTM_PAGE_FLAG_VMALLOC;
-	}
+	ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(*ttm->pages));
 }
 
 static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
 {
-	if (ttm->page_flags & TTM_PAGE_FLAG_VMALLOC) {
-		vfree(ttm->pages);
-		ttm->page_flags &= ~TTM_PAGE_FLAG_VMALLOC;
-	} else {
-		kfree(ttm->pages);
-	}
+	drm_free_large(ttm->pages);
 	ttm->pages = NULL;
 }