Return codes got updated in 
60e1975acb48fc3d74a3422b21dde74c977ac3d5
(btrfs: return errno instead of -1 from compression)
lzo wrapper returns E2BIG in this case, do the same for zlib.
Signed-off-by: David Sterba <dsterba@suse.cz>
                if (workspace->def_strm.total_in > 8192 &&
                    workspace->def_strm.total_in <
                    workspace->def_strm.total_out) {
-                       ret = -EIO;
+                       ret = -E2BIG;
                        goto out;
                }
                /* we need another page for writing out.  Test this