GFS2: Add Orlov allocator

Just like ext3, this works on the root directory and any directory
with the +T flag set. Also, just like ext3, any subdirectory created
in one of the just mentioned cases will be allocated to a random
resource group (GFS2 equivalent of a block group).

If you are creating a set of directories, each of which will contain a
job running on a different node, then by setting +T on the parent
directory before creating the subdirectories, each will land up in a
different resource group, and thus resource group contention between
nodes will be kept to a minimum.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 01c4975..30de4f2 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -643,7 +643,7 @@
 			goto out_unlock;
 
 		requested = data_blocks + ind_blocks;
-		error = gfs2_inplace_reserve(ip, requested);
+		error = gfs2_inplace_reserve(ip, requested, 0);
 		if (error)
 			goto out_qunlock;
 	}