dm-loop (for qole)
 

These two modules enable dm-loop:

http://my.arava.co.il/~matan/770/dm-mod.ko
http://my.arava.co.il/~matan/770/dm-loop.ko


To use it you need dmsetup package which is available from debfarm repository. After installing the package add a symlink from dmlosetup to dmsetup, and run something like:

dmlosetup 0 /z/debian.img

Then mount /dev/dm-0 /opt


In my (very unscientific) tests it is about 4 times faster than loop, and very close to direct access speed.

Re: dm-loop (for qole)
 

Matan,

you rock.

Re: dm-loop (for qole)
 

Just a slight correction, the 0 is wrong, it should be loop0 instead:

OpenOffice loads at least 2x as fast, which is a huge improvement.

Thanks so much! I've already incorporated the Matan TurboLoop (c) into my next version of Easy Debian... :D

Re: dm-loop (for qole)
 

Matan: Can I probe what patch you used for the 2.6.21 kernel to get this compiled?, as it's not part of the 2.6.21 kernel by default. Reason is that I would like to compile some .o's that would follow kernel updates for Deblet.

Your work is immensely useful both for qole's Easy Debian and for my "Deblet-in-a-file" (I've just managed to compile dmsetup.static, may be interesting as well for qole), where I make a Deblet system boot entirely from a file on a vfat partition.

Re: dm-loop (for qole)
 

I'm using iodine in an airport, so I won't include a link, but dm-loop project has patches for 2.6.20 which apply cleanly to 2.6.21-omap1.

Re: dm-loop (for qole)
 

Yikes. Now there's a man who likes his free wi-fi, no matter how slow.

Re: dm-loop (for qole)
 

Deblet-in-a-file now also uses dm-loop :) thanks for the great work Matan.

Re: dm-loop (for qole)
 

Matan: Do you think you could build these modules for the Maemo 5 kernel?

Re: dm-loop (for qole)
 

I am usually not interested in software without hardware to run on, so I do not expect to install Maemo 5 SDK until (and if) a Maemo 5 tablet is available.

There are patches that should apply to modern kernel, see here:

http://osdir.com/ml/linux.kernel.dev.../msg00038.html

I believe that anyone who has the SDK installed can easily patch and compile the kernel.

Re: dm-loop (for qole)
 

I discovered last night that the lack of a dm-loop in Fremantle is the least of my problems. I am finding it very difficult to test my Easy Debian scripts in the SDK when there's not even a "mount" command...

Re: dm-loop (for qole)
 

qwerty12 is my first tester of the easy-chroot stuff in Fremantle, and he noticed the missing dm-loop.

I would like someone to upload the dm-loop kernel modules to Extras for both Diablo and Fremantle. It really isn't right that I'm packaging this as part of my easy-chroot package; my package should depend on this package.

At the end of September, Attila77 graciously offered to get the Diablo dmloop package into the repositories for me... He wrote to me:

"Just to let you know, I got the module built, but there is a bit of a snag, the i386 part of the autobuilder process dies a horrible death as it can't really deal with the arm kernel stuff and thus marks the whole package as failed. I already wrote Jeremiah about this, so hopefully with a little help I'll have this in extras shortly."

Here's a link to his package (currently in my repository, doesn't seem to be in Extras yet).

So this looks like it will be quite a challenge for anyone willing to try it for Fremantle... And can anyone help getting the package to build for Diablo?

Re: dm-loop (for qole)
 

If it means something, I can 'fake' the i386 part, so only the ARM module gets built. Not pretty, but it would work with extras until Jeremiah gets some time to play with it.

BTW I though you said 'simple' loop is good enough in Fremantle ?

Re: dm-loop (for qole)
 

Well, setting the Architecture field in debian/control to armel ensures that it only gets built for ARM; no "faking" required. TBH, I don't see why the modules would be needed in an I386 Scratchbox anyway; Scratchbox insists on reporting your hosts' kernel version when running "uname -a" so I doubt they're gonna work either way.

P.S. I'd say that the modules are needed for Fremantle. "apt-get install nokia-binaries nokia-apps" completed when I woke up in the morning... :)

Re: dm-loop (for qole)
 

I know about (and set) that field, but the autobuilder DOES make (or rather, tries to make) something in i386, and that's where it blows up (complains about the cross-compiler, but the actual error is not there, it shouldn't get that far in the first place)

Re: dm-loop (for qole)
 

Seeing as you will have already once uploaded it to the autobuilder, would it be too much trouble to ask for the source package so I can look at it (not to upload with my name as the Maintainer ;)), please?

Re: dm-loop (for qole)
 

Thanks guys.

It's because of you and this stuff that you do that I love this place.

<warm fuzzies>

Re: dm-loop (for qole)
 

Sent. I believe the thing is quite self-explanatory, I just extract the kernel source, patch the dmloop stuff, compile, and that's about it. It's probably failing because of something trivial (=me not seeing something 'cause my eyes get in the way). Under a VM on my ancient hardware, every attempt was ~30 minutes so I lost interest in the trial and error method real quick, especially as I had my armel.deb :) You are very welcome to become maintainer :)

PS The architecture is 'all' in the archive, which is wrong, I know, I was just trying to figure out a few arch related things and it remained that way in the last package.

PPS Also, Matan showed some interest in packaging modules, so if you figure out what I was missing, post here so anyone trying to add a separate deb module can work it out.

Re: dm-loop (for qole)
 

https://garage.maemo.org/pipermail/e...er/010773.html =)

Re: dm-loop (for qole)
 

qwerty12 for president ! :D

Re: dm-loop (for qole)
 

Hi guys,

I've finally had a chance to look at the package that you built. It has the kernel modules, but now we need the dmsetup package in Extras too (see first post in the thread).

The dmsetup package should additionally have a symbolic link made (in postinst), /sbin/dmlosetup, which points to /sbin/dmsetup.

As soon as these things appear in the repositories, I can start depending on them for my package instead of providing them.

Re: dm-loop (for qole)
 

What extra things would be required to add encryption here? Is yet another kernel module needed?

I could see many use-cases for an encrypted file system inside an image file on your mobile device.

Re: dm-loop (for qole)
 

I'll try and push dmsetup into extras tonight barring some devmapper dependency funk.

Re: dm-loop (for qole)
 

Re: dm-loop (for qole)
 

The dependancies I mentioned here. Instead of dmsetup I recommend cryptsetup-luks (aka cryptsetup nowadays) because it only has that one purpose. Just check out each of their manuals...

Together with an Ext2/Ext3 driver this should be compatbile with FreeOTFE, making it possible to even access r/w mode of both the image as well as the filesystem on a little endian machine such as Windows/x86-32. Like TrueCrypt. That means, that for example the image can be put on MicroSD, and a Windows/x86-32 user (most used desktop platform...) can write stuff onto it.

Re: dm-loop (for qole)
 

So now, in theory, you can get your own turbo loop in Diablo without needing to install easy chroot. I'll test it out and get back to you...

Re: dm-loop (for qole)
 

Agh! post-removal script for dmsetup is broken! Please fix!

(I expected the conflict with easy-chroot; I didn't expect the package to get "jammed" trying to remove!)

Re: dm-loop (for qole)
 

Whoops :o Knew that softlink shouldn't be in postinst/rm... New package will be on it's way shortly.

Re: dm-loop (for qole)
 

Upon further inspection, this wasn't caused by the softlink... the hacked version of dmsetup in the qole.org repo did not use the udev rules but simply ignored that part of the original package. Now, I fixed the failure and you DO get the udev rule as per the original package (can't be a bad thing, right ?). Yell if this is not what you wanted.

PS. As it's about 2:40 AM here and my eyes are closing, I first uploaded the package to the Fremantle queue by mistake. :o The fun part is that it actually went through the autobuilder without a hitch, so... we have devmapper in Fremantle :D

EDIT: If you don't know how to solve the postrm/exec format problem, just do a
and all will be well

Re: dm-loop (for qole)
 

Looks like everything installs OK in Diablo. Kernel modules load, dmlosetup works, and I can mount an image just fine.

One little error when installing the new packages:
Just for fun, I tried dmlosetup in Fremantle. It needs the kernel drivers. :(

So someone still needs to build the drivers for kernel version 2.6.28-omap1 (armv71).

Re: dm-loop (for qole)
 

I'm certainly not going to attempt an autobuilder build when the SDK kernel source is out of date compared with what's on the device itself...

Re: dm-loop (for qole)
 

Yeah, that one was a headscratcher - kernel on a preproduction device newer than the 'final' SDK... Or are we going to have torrent style final-ultimate-repack SDKs ? :D

Re: dm-loop (for qole)
 

Well, until someone attempts a build of dm-mod.ko and dm-loop.ko for Fremantle, you'll have to putter along with the "regular" loop... :(

Re: dm-loop (for qole)
 

That is clear, it's just that it seems things are still in flux on the kernel level. Until the device-sdk-autobuilder trinity settles on a common 'final' version, it's not really worth the effort.

Re: dm-loop (for qole)
 

Hmm, what I find strange, is that dm-loop is not in mainline kernel. What is reason for this? I can hardly find information about it, and cannot find module pre-compiled either.

I have in fact 2 dm modules loaded (no idea why but they're loaded): dm_crypt and dm_road but they use _ underscore not - stripe. WTF?

Re: dm-loop (for qole)
 

Ok! Quim has announced the new final-final SDK, and it should have the shipping kernel version in it. Can one of you guys work your magic and get the dm-loop packages into Fremantle extras-devel? I would be so grateful!

Re: dm-loop (for qole)
 

Just a visual thank-you to Matan, qwerty12 and attila77...

http://farm3.static.flickr.com/2494/...5984d011_o.png

Look at those beautiful, wonderful dependencies. Sweet.


EDIT: I've promoted the dm-loop stuff to Extras, because I need them for my packages...

Re: dm-loop (for qole)
 

Attila? qwerty12? Can someone fix Diablo dmsetup, please?

Re: dm-loop (for qole)
 

Errr... I thought I fixed it a while back ? I did not test extensively but a quick test run went through OK... Can you confirm the problem with the latest dmsetup in extras-devel ? On a side note, now that the release firmware is out, I planned on a little Fremantle dm_loop hackery tonight.

Re: dm-loop (for qole)
 

Someone else reported the same error when trying to install the dmsetup package. Did you fix this one?

Re: dm-loop (for qole)
 

I finally tried out the Fremantle packages in Extras-devel. In fact, I've made my Fremantle Easy Chroot package use the dmloop system if it is installed.

Some things I would like:

• I wish kernel-module-dmloop depended on dmsetup and libdevmapper1.02.1. It would be nice if the dependencies went both ways, but it is essential to pull in dmsetup if you install kernel-module-dmloop.
• I was doing some testing, uninstalling and reinstalling the dmsetup packages in Fremantle. I had the same problem with that dmsetup.rules file not being deleted when the package is removed.