Not really. The gfs_mkfs command decides exactly where everything should go and you have no choice in the matter. The volume is carved into logical "sections." The first and last sections are for multiple resource groups, based roughly on the rg size specified on the gfs_mkfs commandline. The journals are always placed between the first and last section. Specifying a different number of journals will force gfs_mkfs to carve the section size smaller, thus changing where your journals will end up.