From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com ([209.132.183.28]:45890 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751737AbdG1Ozf (ORCPT ); Fri, 28 Jul 2017 10:55:35 -0400 From: Jeff Moyer Subject: Re: [PATCH v4 2/4] generic: test mmap io fom DAX to non-DAX References: <1492008380-29164-1-git-send-email-xzhou@redhat.com> <1492413255-11146-1-git-send-email-xzhou@redhat.com> <1492413255-11146-3-git-send-email-xzhou@redhat.com> <20170418101226.GA15898@infradead.org> Date: Fri, 28 Jul 2017 10:55:33 -0400 In-Reply-To: <20170418101226.GA15898@infradead.org> (Christoph Hellwig's message of "Tue, 18 Apr 2017 03:12:26 -0700") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Sender: fstests-owner@vger.kernel.org To: Christoph Hellwig Cc: Xiong Zhou , fstests@vger.kernel.org, ross.zwisler@linux.intel.com, dan.j.williams@intel.com, eguan@redhat.com List-ID: Christoph Hellwig writes: > On Mon, Apr 17, 2017 at 03:14:13PM +0800, Xiong Zhou wrote: >> Mount TEST_DEV as non-DAX, SCRATCH_DEV as DAX, then >> do mmap DIO from DAX to non-DAX. >> >> This test is split from generic/413. Since DIO from DAX >> to non-DAX is only supported/doable when device underneath >> has memory(struct page) backend. >> >> By ndctl looking at SCRATCH_DEV, skip this test if it is >> not in "memory mode". > > DAX devices don't need to be something using NFIT, so I don't think this > method is correct. Memory mode does not depend on an NFIT. There's a superblock stored in the persistent memory that tracks its mode when labels are not present. -Jeff