From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: af_xdp zero copy ideas Date: Wed, 14 Nov 2018 03:10:04 -0500 Message-ID: <20181114025153-mutt-send-email-mst@kernel.org> References: <20180604120601.18123-1-bjorn.topel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org To: bjorn.topel@intel.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:57538 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728391AbeKNSMQ (ORCPT ); Wed, 14 Nov 2018 13:12:16 -0500 Content-Disposition: inline In-Reply-To: <20180604120601.18123-1-bjorn.topel@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: So a I mentioned during the presentation for the af_xdp zero copy I think it's pretty important to be able to close the device and get back the affected memory. One way would be to unmap the DMA memory from userspace and map in some other memory. It's tricky since you need to also replace the mapping to the backing file which could be hugetlbfs, tmpfs, just a file ... HTH, -- MST