[PATCH] uml: tidying COW code

Improve (especially for coherence) some prototypes, and return code of
init_cow_file in error case - for a short write return -EINVAL, otherwise
return the error we got!

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/drivers/cow_user.c b/arch/um/drivers/cow_user.c
index d1c86bc..61951b7 100644
--- a/arch/um/drivers/cow_user.c
+++ b/arch/um/drivers/cow_user.c
@@ -362,7 +362,8 @@
 	if(err != sizeof(zero)){
 		cow_printf("Write of bitmap to new COW file '%s' failed, "
 			   "err = %d\n", cow_file, -err);
-		err = -EINVAL;
+		if (err >= 0)
+			err = -EINVAL;
 		goto out;
 	}