FILEIO_TGT handler
User space program fileio_tgt uses interface of SCST's scst_user dev handler and allows to see how it works in various modes. Fileio_tgt provides mostly the same functionality as the kernel space SCST's scst_vdisk handler. Both support O_DIRECT; the in-kernel handler requires asynchronous I/O for that mode. Fileio_tgt does not support BLOCKIO. See SCST's README for the current access-mode semantics and safety requirements.
You can find the latest development version of this handler in the SCST Git repository. See the download page how to setup access to it.