From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH 5/6] xfs: move non-inline symlinks to the pagecache
Date: Sat, 25 Apr 2015 15:57:28 +0100
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Cc: Dave Chinner <david@fromorbit.com>, xfs@oss.sgi.com,
	linux-fsdevel@vger.kernel.org
To: Christoph Hellwig <hch@lst.de>
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On Sat, Apr 25, 2015 at 04:16:12PM +0200, Christoph Hellwig wrote:
> Al, what do you think about adding a new
> 
> i_link member to the union of i_pipe, i_bdev and i_cdev.  That we
> we can cache a link acquired by any way for direct use in the VFS.
> 
> This has a few use cases:  inline links can be set up directly
> when reading the inode, and we never need to call into ->follow_link.
> 
> Formats like the XFS v5 symlinks can be read in once by whatever
> way we want, and following accesses can be done RCU safe and
> without calling into the filesystem.
> 
> Note that caching the symlink in a kmalloc'ed buffer might be
> more efficient than the pagecache for most cases anyway.

Hmm...  When would you free the sucker?