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Date: Thu, 9 Mar 2017 09:21:37 -0500
From: "Theodore Ts'o" <tytso@mit.edu>
To: Jeff Layton <jlayton@redhat.com>
Cc: Jan Kara <jack@suse.cz>, Ross Zwisler <ross.zwisler@linux.intel.com>,
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        NeilBrown <neilb@suse.com>
Subject: Re: [PATCH 0/3] mm/fs: get PG_error out of the writeback reporting
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On Thu, Mar 09, 2017 at 07:43:12AM -0500, Jeff Layton wrote:
> 
> Maybe we need a systemwide (or fs-level) tunable that makes ENOSPC a
> transient error? Just have it hang until we get enough space when that
> tunable is enabled?

Or maybe we need a new kernel-internal errno (ala ERESTARSYS) which
means it's a "soft ENOSPC"?  It would get translated to ENOSPC if it
gets propagated to userspace, but that way for devices like dm-thin or
other storage array with thin volumes, it could send back a soft
ENOSPC, while for file systems where "ENOSPC means ENOSPC", we can
treat those as a hard ENOSPC.

						- Ted