New helper - current_umask()

current->fs->umask is what most of fs_struct users are doing.
Put that into a helper function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 8dde84b..bbee587 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1509,7 +1509,7 @@
 		attr.ia_mode = nd->intent.open.create_mode;
 		attr.ia_valid = ATTR_MODE;
 		if (!IS_POSIXACL(dir))
-			attr.ia_mode &= ~current->fs->umask;
+			attr.ia_mode &= ~current_umask();
 	} else {
 		attr.ia_valid = 0;
 		BUG_ON(nd->intent.open.flags & O_CREAT);