Re: [PATCH 1/2] Documentation: iomap: Add missing flags description

[Christoph Hellwig <hch@infradead.org>]

On Fri, Apr 04, 2025 at 10:36:32AM +0100, John Garry wrote:
> > @@ -243,6 +243,11 @@ The fields are as follows:
> >        regular file data.
> >        This is only useful for FIEMAP.
> > +   * **IOMAP_F_BOUNDARY**: This indicates that I/O and I/O completions
> > +     for this iomap must never be merged with the mapping before it.
> 
> This is just effectively the same comment as in the code - what's the use in
> this?

Darrick asked for this file to have full comments.  I'm more on your
side here as a lot of this seem redundant.

> 
> > +     Currently XFS uses this to prevent merging of ioends across RTG
> > +     (realtime group) boundaries.
> > +
> >      * **IOMAP_F_PRIVATE**: Starting with this value, the upper bits can
> >        be set by the filesystem for its own purposes.
> 
> Is this comment now out of date according to your change in 923936efeb74?

Also we probably should not detail file system behavior here, but a
high level description of what it is useful.