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Date: Sat, 22 Nov 2014 08:22:01 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Konstantin Belousov <kostikbel@gmail.com>
Subject: Re: RFC: patch to make d_fileno 64bits
Message-ID: <20141122162201.GA27585@infradead.org>
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On Sat, Nov 22, 2014 at 05:34:27PM +0200, Konstantin Belousov wrote:
> For syscalls 156 and 196 (and some more), the converter must be written
> in the vfs_syscalls.c which translates the new dirents into old dirents,
> at the level of best efforts.

FYI, you might want to look at the high level construct we use for that
in Linux, where we pass a function pointer to format the dirent to the
VOP_READDIR equivalent.  The function pointer is passed by the caller
and can format all kinds of different dirent stuctures.  This hasn't
just been helpful for the 64bit ino dirent transition, but also for
foreign OS compatibility layers and in-kernel consumers like nfsd.