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From: Matthew Wilcox <willy@linux.intel.com>
Subject: Re: Write atomicity guarantees
Date: Thu, 24 Apr 2014 14:25:13 -0400
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On Thu, Apr 24, 2014 at 11:10:09AM -0700, Purush Gupta wrote:
> That would require a new NVMe write command semantic with descriptors
> currently its not there.

Yes ... I don't want to start defining such a command on linux-fsdevel.
What I'm hearing is that there's no benefit to a device that can guarantee
to write multiple contiguous sectors in a non-torn manner over a device
that can write a single sector in a non-torn manner.

For any real benefit, filesystems need (and Linux needs to introduce
plumbing for) vectored atomic writes.