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From: Jeff Moyer <jmoyer@redhat.com>
To: Dan Williams <dan.j.williams@intel.com>
Cc: "linux-nvdimm\@lists.01.org" <linux-nvdimm@ml01.01.org>,
        Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>,
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Subject: Re: [PATCH v3] libnvdimm, region: sysfs trigger for nvdimm_flush()
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X-PCLoadLetter: What the f**k does that mean?
Date: Thu, 27 Apr 2017 15:43:41 -0400
In-Reply-To: <CAPcyv4hDmwSO8szjn+mqL6xpW2H92WsTDn=8qLtJi7Y8kduX5Q@mail.gmail.com>
        (Dan Williams's message of "Thu, 27 Apr 2017 12:21:54 -0700")
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Dan Williams <dan.j.williams@intel.com> writes:

> We also still seem to need a discovery mechanism as I've had questions
> about "how do I tell if my system supports deep flush?". That's where
> sysfs is much better than an ioctl. The need for deep flush discovery
> tips the scales, at least for me, to also do deep flush triggering
> through the same interface.

Return ENXIO or EOPNOTSUPP from the ioctl when it isn't supported?

Cheers,
Jeff