Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for TPM 2.0

[Jason Gunthorpe]

On Mon, Jan 02, 2017 at 03:22:10PM +0200, Jarkko Sakkinen wrote:
> Added a ioctl for creating a TPM space. The space is isolated from the
> other users of the TPM. Only a process holding the file with the handle
> can access the objects and only objects that are created through that
> file handle can be accessed.

I don't understand this comment. /dev/tpmX is forced to be
single-process-open, so how can there ever be more than 1 FD for it?

Since the space is tied to that single fd these patches just create a
way for the single user-space process to auto-cleanup if it crashes?

Is that the entire intent of this design? I guess it is OK as a
stepping point..

> -ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
> -		     unsigned int flags)
> +ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
> +		     u8 *buf, size_t bufsiz, unsigned int flags)

Please split this patch so that 'struct tpm_space' introduction is in
its own patch and the actual UAPI change is in a much smaller
patch. It is very hard to see the uapi stuff in all of this churn.

Jason