swapon feature additions

swapon feature additions

[Dave Reisner]

Hi Karel,

I was interested in making a few changes to swapon, but I figured I'd
inquire as to whether or not they're welcome first.

1) Introduce optional libmount support. This involves first refactoring
reading of /etc/fstab to remove the duplicated code and use callbacks
instead. Breaking out the functionality into libmount-powered and
non-libmount-powered code is then much cleaner.
2) Teach swapon/swapoff to only look at files or partitions. The use
case in mind is specifically for unswapping only files at shutdown, as
partitions can remain mounted without harm.

Does this seem reasonable? Is this functionality wanted? Anything else I
should be aware of?

Thanks,
Dave Reisner

Re: swapon feature additions

[Karel Zak]

On Thu, Oct 27, 2011 at 03:40:56PM -0400, Dave Reisner wrote:
> 1) Introduce optional libmount support. This involves first refactoring
> reading of /etc/fstab to remove the duplicated code and use callbacks
> instead. Breaking out the functionality into libmount-powered and
> non-libmount-powered code is then much cleaner.

 I'd like to move all swapon(8) functionality to libmount and replace
 the whole swapon(8) by a small libmount based util. Unfortunately,
 swapon/swapoff support in libmount is not implemented yet.

> 2) Teach swapon/swapoff to only look at files or partitions. The use
> case in mind is specifically for unswapping only files at shutdown, as
> partitions can remain mounted without harm.

 This is probably more important, it would be nice to have 
 
    swapoff --all --files-only

> Does this seem reasonable? Is this functionality wanted? Anything else I
> should be aware of?

 Yes, my suggestion is to start with 2) :-)

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com