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Date: Tue, 27 Jan 2015 09:30:45 -0800
From: Christoph Hellwig <hch@infradead.org>
To: P??draig Brady <P@draigBrady.com>
Cc: lkml <linux-kernel@vger.kernel.org>, aneesh.kumar@linux.vnet.ibm.com,
        "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Subject: Re: RFC: More functions allowed with O_PATH
Message-ID: <20150127173045.GA21651@infradead.org>
References: <54C78B8F.9090903@draigBrady.com>
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On Tue, Jan 27, 2015 at 12:58:55PM +0000, P??draig Brady wrote:
> Since fsync(), fdatasync(), syncfs() work on an identifying descriptor,
> and all work against a read-only file for example,
> should any/all these functions work with a descriptor opened with O_PATH ?

fsync and fdatasync work on the file data, so they defintively
shouldn't.

syncfs might make sense as we just use it as a handle for the containing
filesystem.

Adding fchmod and fchown would be more useful as they are allowed by
Posix on O_EXEC and O_SEARCH fds.