treewide: Add __GFP_NOWARN to k.alloc calls with v.alloc fallbacks

Don't emit OOM warnings when k.alloc calls fail when
there there is a v.alloc immediately afterwards.

Converted a kmalloc/vmalloc with memset to kzalloc/vzalloc.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index 64fbb83..b12c11e 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -393,7 +393,7 @@
 	 * we must not block on IO to ourselves.
 	 * Context is receiver thread or dmsetup. */
 	bytes = sizeof(struct page *)*want;
-	new_pages = kzalloc(bytes, GFP_NOIO);
+	new_pages = kzalloc(bytes, GFP_NOIO | __GFP_NOWARN);
 	if (!new_pages) {
 		new_pages = __vmalloc(bytes,
 				GFP_NOIO | __GFP_HIGHMEM | __GFP_ZERO,