Re: [PATCH] tpm: add support for partial reads

From: James Bottomley
Date: Mon Jul 23 2018 - 17:18:48 EST


On Mon, 2018-07-23 at 13:53 -0700, Tadeusz Struk wrote:
> On 07/23/2018 01:19 PM, Jarkko Sakkinen wrote:
> > In this case I do not have any major evidence of any major benefit
> > *and* the change breaks the ABI.
>
> As I said before - this does not break the ABI.

The current patch does, you even provided a use case in your last email
(it's do command to get sizing followed by do command with correctly
sized buffer).Â

However, if you tie it to O_NONBLOCK, it won't because no-one currently
opens the TPM device non blocking so it's an ABI conformant
discriminator of the uses. Tying to O_NONBLOCK should be simple
because it's in file->f_flags.

James