Hello,

I have a couple of observations/questions regarding vendor specific
commands over NVMf and I was hoping to get your take on this.

- I can get vendor specific *IO *commands to work in my custom bdev by
supporting SPDK_BDEV_IO_TYPE_NVME_IO. However, doing the same for
*Admin *commands
fails. Is there a reason why we are blocking the vendor specific range of
C0h-FFh for Admin commands (see spdk_nvmf_ctrlr_process_admin_cmd).
- The current bdev API to complete a NVMe specific request is
spdk_bdev_io_complete_nvme_status(struct spdk_bdev_io *bdev_io, int sct,
int sc) but it only takes in the 2 status code that are written to the
completion queue status field. I would also like to set the CDW0 of the
completion queue. Are there any plans to support this or do we want to keep
the bdev API as front-end protocol agnostic as possible?
I guess one way to support it would be to add an additional field to
bdev_io's structure like there is for the NVMe/SCSI specific status code
handling, but again, do we want to add more protocol specifics to bdev_io?
Are the any other options to set CDW0?

Thanks for your help.

-- Michael