Sorry for the bad email threading. Forgot to pass git send-email --compose so responding on the first email.
The following patches were made over Linus's tree. They reduce the memory use for vhost-scsi. For a simple device with 1 queue and 128 cmds we use around 25 MB. These patches allow us to reduce that to 8.2 MB when supporting up to 8 MB IOs (the current passthrough max). For a more complex device with 16 queues we use around 2.5 GB. These patches allow us to reduce that to 77.1 MB when supporting 8 MB IOs.
