Re: [PATCH v2 00/10] Copy Offload in NVMe Fabrics with P2P PCI Memory

From: Logan Gunthorpe
Date: Thu Mar 01 2018 - 16:15:18 EST




On 01/03/18 02:10 PM, Jerome Glisse wrote:
It seems people miss-understand HMM :( you do not have to use all of
its features. If all you care about is having struct page then just
use that for instance in your case only use those following 3 functions:

hmm_devmem_add() or hmm_devmem_add_resource() and hmm_devmem_remove()
for cleanup.

To what benefit over just using devm_memremap_pages()? If I'm using the hmm interface and disabling all the features, I don't see the point. We've also cleaned up the devm_memremap_pages() interface to be more usefully generic in such a way that I'd hope HMM starts using it too and gets rid of the code duplication.

Logan