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Date: Sun, 23 Mar 2025 07:40:29 +0100
From: Christoph Hellwig <hch@lst.de>
To: John Garry <john.g.garry@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>, alx@kernel.org, brauner@kernel.org,
	djwong@kernel.org, dchinner@redhat.com, linux-man@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org,
	linux-kernel@vger.kernel.org, ojaswin@linux.ibm.com,
	ritesh.list@gmail.com, martin.petersen@oracle.com,
	linux-api@vger.kernel.org
Subject: Re: [PATCH RFC] statx.2: Add stx_atomic_write_unit_max_opt
Message-ID: <20250323064029.GA30848@lst.de>
References: <20250319114402.3757248-1-john.g.garry@oracle.com> <20250320070048.GA14099@lst.de> <c656fa4d-eb76-4caa-8a71-a8d8a2ba6206@oracle.com> <20250320141200.GC10939@lst.de> <7311545c-e169-4875-bc6c-97446eea2c45@oracle.com>
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On Fri, Mar 21, 2025 at 10:20:21AM +0000, John Garry wrote:
> Coming back to what was discussed about not adding a new flag to fetch this 
> limit:
>
> > Does that actually work?  Can userspace assume all unknown statx
> > fields are padded to zero?
>
> In cp_statx, we do pre-zero the statx structure. As such, the rule "if 
> zero, just use hard limit unit max" seems to hold.

Ok, canwe document this somewhere?