On Thu, Jun 26, 2025 at 10:50:22AM -0400, James Bottomley wrote: > On Thu, 2025-06-26 at 13:19 +0300, Jarkko Sakkinen wrote: > > From: Jarkko Sakkinen <jarkko.sakki...@opinsys.com> > > > > Create a cleanup class for struct tpm_buf using DEFINE_CLASS(), which > > will guarantee that the heap allocated memory will be freed > > automatically for the transient instances of this structure, when > > they go out of scope. > > > > Wrap this all into help macro CLASS_TPM_BUF(). > > > > A TPM buffer can now be declared trivially: > > > > CLASS_TPM_BUF(buf, buf_size); > > Well, that's not all ... you're also adding a size to the API that we > didn't have before, which should at least be documented in the commit > message and probably be a separate patch. > > What is the reason for this, though? The reason we currently use a > page is that it's easy for the OS to manage (no slab fragmentation > issues). The TCG reference platform defines this to be just under 4k > (actually 4096-0x80) precisely because TPM implementations don't do > scatter gather, so they don't want it going over an ARM page, so > there's no danger of us ever needing more than a page.
Thanks for the valuable feedback. I can drop "buf_size" parameter. It is not a priority, and I also agree with your comments. > > Regards, > > James BR, Jarkko
