Re: fscache review comments, part 3

[Christoph Hellwig <hch@infradead.org>]

On Fri, Oct 06, 2006 at 02:25:54PM +0100, David Howells wrote:
> Christoph Hellwig <hch@infradead.org> wrote:
> 
> >  - generic_file_buffered_write_one_kernel_page seems generally fine, but
> >    you must not call this directly from cachefiles but rather go through
> >    a file operation for it.
> 
> I can't do that for one very good reason: you insisted that I take out[*] all
> the provision of a struct file * for doing I/O to the cache, and without that
> I can't call file ops.  You can't have it both ways.  Sorry.

A file operation doesn't actually have to take a file struct, they're
also available from the inode.  But in some way you are right, doing that
as the file_operations level without a struct file is indeed rather odd.

The important point here is that we definitly need one of the operation
vectors to go through instead of a direct call.   I'm rather tired of all
this arguing here, so if the higher gods think we absolutely need cachefs
now just add a method somewhere with the signature of your function and
hopefull someone will clean up the utter mess later.  It's not like our
current set of read/write methods makes any sense.