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Date: Sat, 22 Nov 2014 19:56:20 +0200
From: Konstantin Belousov <kostikbel@gmail.com>
To: Christoph Hellwig <hch@infradead.org>
Subject: Re: RFC: patch to make d_fileno 64bits
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On Sat, Nov 22, 2014 at 08:22:01AM -0800, Christoph Hellwig wrote:
> 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.

Yes, this is very promising approach, I agree.
Thank you for the pointer.