Re: [PATCH RFC] mm: Add f_ops->populate()

On Sun, Mar 06, 2022 at 04:15:33AM +0200, Jarkko Sakkinen wrote:

Sometimes you might want to use MAP_POPULATE to ask a device driver to initialize the device memory in some specific manner. SGX driver can use this to request more memory by issuing ENCLS[EAUG] x86 opcode for each page in the address range.

Add f_ops->populate() with the same parameters as f_ops->mmap() and make it conditionally called inside call_mmap(). Update call sites accodingly.

Your device driver has a ->mmap operation. Why does it need another one? More explanation required here.