Re: [RFC] [PATCH 2/8] inode-diet: Move i_pipe into a union

Brian F. G. Bidulock
2006-06-20T15:23:56Z

Theodore,

On Mon, 19 Jun 2006, Theodore Tso wrote:
>
> As was mentioned in earlier comment, this will be problematic for the
> out-of-tree System V Streams code, which hijacks i_pipe as another
> place to store 4 bytes of random data needed for the Streams code (I
> believe they needed a pointer to the stream head -- the v_str pointer
> in a legacy Unix system's inode). But, that is an out-of-tree kernel
> module, and it's a clear abuse of the i_pipe element in any case.

It's used for implementing STREAMS-based FIFOs. Which is a proper use
of i_pipe (which is for FIFOs). Pipes (both mainline and STREAMS-based
pipes) can use i_private instead of i_pipe.

For the same reason why i_pipe cannot be combined with i_private.