[RFC PATCH v3 3/3] nvme: wire up support for async passthrough

[Christoph Hellwig]

On Wed, Mar 17, 2021 at 09:45:50AM -0700, Keith Busch wrote:
> > +	if (ioucmd) { /* async handling */
> > +		u32 effects;
> > +
> > +		effects = nvme_command_effects(ns->ctrl, ns, cmd->common.opcode);
> > +		/* filter commands with non-zero effects, keep it simple for now*/
> 
> You shouldn't need to be concerned with this. You've wired up the ioucmd
> only to the NVME_IOCTL_IO_CMD, and nvme_command_effects() can only
> return 0 for that.
> 
> It would be worth adding support for NVME_IOCTL_IO_CMD64 too, though,
> and that doesn't change the effects handling either.

There is no good reason to support the non-64 structure in new code.
And we really should support the admin command submission (on the char
device node) as well.