From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: John Richard Moser <nigelenki@comcast.net>
Subject: Re: Suspend to disk:  do we HAVE to use swap?
Date: Tue, 31 Oct 2006 07:16:39 +0100
User-Agent: KMail/1.9.1
Cc: linux-kernel@vger.kernel.org
References: <4546C637.5080504@comcast.net>
In-Reply-To: <4546C637.5080504@comcast.net>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="utf-8"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200610310716.40181.rjw@sisk.pl>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1161
Lines: 28

On Tuesday, 31 October 2006 04:42, John Richard Moser wrote:
> Something dumb came into my head, and the question is thus brought up
> here:  Do we HAVE to use swap for suspend to disk? How about the file
> system?

In short, we could use regular files for the suspend in the same way in which we
use them for swap.  Namely, we could bmap() a file and create a map of it
(eg. with extents) that would be used for accessing the corresponding disk
sectors at the block device level.  Then, to be able to read the image the
resume code would have to be provided with the number of the sector in which
the suspend image header is located.

However, we already have code that allows us to use swap files for the suspend
and turning a regular file into a swap file is as easy as running 'mkswap' and
'swapon' on it.

Greetings,
Rafael


-- 
You never change things by fighting the existing reality.
		R. Buckminster Fuller
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/