From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Date: Wed, 16 Nov 2011 03:42:56 -0500
Subject: [Cluster-devel] fallocate vs O_(D)SYNC
Message-ID: <20111116084256.GA22963@infradead.org>
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It seems all filesystems but XFS ignore O_SYNC for fallocate, and never
make sure the size update transaction made it to disk.

Given that a fallocate without FALLOC_FL_KEEP_SIZE very much is a data
operation (it adds new blocks that return zeroes) that seems like a
fairly nasty surprise for O_SYNC users.