Re: [PATCH 5/6] xfs: move non-inline symlinks to the pagecache

[Christoph Hellwig <hch@xxxxxx>]

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.