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

[Tadeusz Struk]

On 07/23/2018 02:13 PM, James Bottomley wrote:
> 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). 

The example I provided was: #1 send a command, #2 read the response header
(10 bytes), get the actual response size from the header and then #3 read
the full response (response size - size of the header bytes).

> 
> 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.

I think that it might be an option. Especially that I have this on top of
the async patch. Let's discuss this when Jarkko is back.

Thanks,
-- 
Tadeusz