TomTom Settlement Aftermath: Get the FAT Out (Groklaw) [LWN.net]

Groklaw recommends a FAT-free diet to avoid Microsoft patent liability issues. "The Linux Foundation's Jim Zemlin got the same message from the TomTom story that I did: just get rid of Microsoft's FAT filesystem: "The technology at the heart of this settlement is the FAT filesystem. As acknowledged by Microsoft in the press release, this file system is easily replaced with multiple technology alternatives. The Linux Foundation is here to assist interested parties in the technical coordination of removing the FAT filesystem from products that make use of it today." OK. Sounds like a plan. There clearly is no "new" Microsoft, and they have evidenced now a lack of interest in any real interoperability with FOSS."

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TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 15:41 UTC (Thu) by cantsin (guest, #4420) [Link] (3 responses)

Removing FAT support from the Linux kernel would mean that Linux systems
would no longer be able to read USB sticks, SD and CF cards of digital
cameras, and basically not mount any mainstream USB storage device.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 15:46 UTC (Thu) by stumbles (guest, #8796) [Link] (1 responses)

Um yep. Now you know why Microsoft chose Tom Tom. Easy prey.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 7:15 UTC (Fri) by ncm (guest, #165) [Link]

As I understand it, TomTom could have avoided the problem entirely just by demonstrating their system never wrote long file names. However, there were other claims, and the case itself would have been expensive regardless of merits, so they settled. TomTom got MS off its back, and MS spread around some FUD, so both sides came out fine. I don't see any implications for anybody else.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 16:10 UTC (Thu) by forthy (guest, #1525) [Link]

You can format USB storage devices with whatever Linux filesystems you like. Or, when it matters, even NTFS. However, to get "the FAT out", it also requires parties like digital cameras to cooperate. Since it's not the Linux desktop users who get sued over FAT, but the device makers (cameras, navigation, etc.), this is the right place. Get the FAT out of these devices, use a file system like ext2, where an Windows IFS driver exists, or one where a driver is already implemented in Windows, like UDF. This might even make Microsoft happy, because to write UDF, you need Vista; previous versions could only read it (maybe third parties could get their act together and write a writing UDF IFS for Windows XP, and put it on the driver CDs supplied with the cameras - or even on the SD cards itself, since reading is possible, anyways. Plus an autorun.inf, so that it installs itself without user interactions...

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 15:53 UTC (Thu) by Hanno (guest, #41730) [Link] (6 responses)

> this file system is easily replaced
> with multiple technology alternatives

Which?

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 16:08 UTC (Thu) by njd27 (subscriber, #5770) [Link]

Again, this article is an oversimplification. Microsoft only claims patent protection over the parts of the Linux VFAT implementation that deal with long filenames. An implementation which can't write long filenames is non-infringing (although somewhat crippled).

FWIW there is an ext2 driver available for Windows.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 17:07 UTC (Thu) by drag (guest, #31333) [Link] (4 responses)

> Which?

Unlike Groklaw I do not think that there will be anything 'Easy' about it. However I do have a idea on what could be used to replace it effectively.

One thing to keep in mind is that I do not think that it is necessary to remove FAT support for Linux distributions. Microsoft repeated stated that they were not targetting Linux or open source with this patent attack and I figure until they actually do then it is worthwhile to simply keep what already exists in place.

However it is important for embedded developers to work out a way to mitigate Microsoft's threat on new devices. So those are the people that need to be concerned about it.

I'll outline my thoughts:

There are a number of different reasons why Fat is the defacto standard for this sort of thing. Reasons like:

1. USB Mass storage is supported by modern OSes by default. As is FAT. This means that you can have your devices used on any OS without requiring users to install extra drivers. This is a HUGE benefit.

2. Fat is simple to impliment and has low resource requirements.

3. Everybody else is using it.

These are all very good reasons. Fabulous and very strong good reasons. Alternatives like ext2 require extra drivers on Windows. And with Window's way of dealing with drivers this means that if people try to move to Ext2 then there would end up being thousands of different versions of ext2 support floating around. USers using multiple devices will probably run into new difficulties. So avoiding installing new drivers for file systems in Windows is a huge priority.

So my idea is to not support USB Mass storage at all on these sorts of devices.

My idea right now, although I haven't looked into it to deeply is to replace USB mass storage + FAT with USB virtual enthernet driver + http + Webdav.

It may sound insane, but I think it would have a good chance of working for many devices.

Remember that we are dealing with consumer embedded devices running Linux with some sort of GUI interface. The processing power and memory requirements needed to run that sort of setup will also be able to run a embedded-style web server. Included on the device may be a small FAT16 partition that can be used to launch a autorun script.

So what this provides you with is the ability to run a nice graphical configuration utility, built into the device. This GUI would be write-once, use-everywere since it will be built using web standards.. the only requirement on the end user side is to have a web browser.

There is precendence for using virtual usb ethernet connections. Many 'Broadband' devices like Cell phones or modems that allow users to connect to 3G networks have virtual ethernet devices that they setup. This is because PPP over USB has a lot of overhead and will be throttled by the USB speeds before it maxes out the wifi connection. Ethernet frames have much lower overhead.

And, like FAT, Webdav is pretty much universally supported by modern OSes and can provide a file system-like interface for Gnome, Windows XP (or newer) and OS X. So if it desirable for a user to simply drag-n-drop files then that is acheivable.

So what this gets you is a nice write-once, run everywere, GUI interface for administrating the device. A nice way to provide links to online resources. Puts a higher degree of control over your device since your not exposing the full file system to the end user. Allows for better feedback from users for important tasks like firmware updates. etc etc.

The added expense can be offset by the fact that you can use native file system drivers and avoid needing additional block-to-flash translation layers needed to support FAT, as well as avoiding Microsoft's licensing costs. And you'll save on packaging and shipping costs since you won't need to bundle drivers so much.

And on top of that if you are creating a device that has additional features like wifi or broadband support then your application would be able to use that also without being re-written or changing user documentation.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 17:25 UTC (Thu) by proski (guest, #104) [Link] (1 responses)

PictBridge would be a simpler solution for connecting to the device. The problem is that users would expect to extract the flash card and read it in a flash reader. That would be a problem if FAT is not used. ISO9660 may be an option, but I'm not sure it would be recognized by Windows on devices that look like hard drives and use partitioning.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 20:16 UTC (Thu) by drag (guest, #31333) [Link]

Well I hope they figure out something, because the alternatives is to end up with devices that require special software to communicate with it. And that is always irritating, I hate device-specific software.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 2:47 UTC (Fri) by jamesh (guest, #1159) [Link] (1 responses)

There are existing protocols to allow USB devices to expose a file system to the host instead of a block device.

Probably the most common ones are PTP and MTP, which are supported by all major operating systems today. So I'd probably pick one of those as a basis rather than bringing ethernet, TCP/IP and WebDav into the mix (things which the device might not have resources to implement).

Another alternative seen in mobile phones is OBEX-FTP over USB. But I don't think OS support is as good (at least with default installs).

Previously they've been used in cases where the device needs to access the storage simultaneously with the host, or the device wants to hide certain things from the host (DRM music).

But I guess patents might be another reason for manufacturers to turn to file system level access protocols.

Get the OBEX out as well

Posted Apr 3, 2009 11:48 UTC (Fri) by pboddie (guest, #50784) [Link]

Another alternative seen in mobile phones is OBEX-FTP over USB.

OBEX doesn't appear to be a proper open standard: the specifications aren't freely available or redistributable - leaked versions and earlier versions don't count - and this makes it undesirable for Free Software, regardless of whether projects already exist that deal with it.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 16:26 UTC (Thu) by JoeBuck (subscriber, #2330) [Link] (5 responses)

Go read the patent claims in question, and notice that every single claim requires the creation of a new filename. In other words, a read-only implementation cannot infringe. Also, an implementation that only allows the creation of traditional "8.3" filenames cannot infringe. So even if these patents are upheld, Linux systems can still read cards from digital cameras.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 18:49 UTC (Thu) by martinfick (subscriber, #4455) [Link] (1 responses)

And delete I presume? It is after all, probably the most common write operation to a camera card (not USB devices in general) done by a linux system.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 2:49 UTC (Fri) by jamesh (guest, #1159) [Link]

I'm pretty sure that when you deleted a file under DOS it was still deleted when you booted into a long filename capable OS. That was one of the design goals for VFAT.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 10:53 UTC (Fri) by etienne_lorrain@yahoo.fr (guest, #38022) [Link] (2 responses)

Just gone and read Wiki (search FAT licensing) at
http://en.wikipedia.org/wiki/File_Allocation_Table
And it seems you should not have a common namespace for short and long filenames - i.e. a readonly implementation where a file can be open by its two names (when it has a long filename) would be covered by the patent.
That is what Linux VFAT do - moreover Linux VFAT is R/W.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 10, 2009 0:06 UTC (Fri) by spitzak (guest, #4593) [Link] (1 responses)

I don't think you can open the file by both names in Linux. The ~ 8.3 name is completely hidden.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 14, 2009 11:52 UTC (Tue) by etienne_lorrain@yahoo.fr (guest, #38022) [Link]

Yes you can, please look at:
http://lwn.net/Articles/326437/

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 17:10 UTC (Thu) by pbrutsch (guest, #4987) [Link] (5 responses)

First off, it's not FAT12 or FAT16 that's the issue, it's FAT32 and its long file name support.

Secondly, a replacement for FAT isn't going to happen. Period.

Until you have a replacement FS that's as simple and as widely supported - remember, it's not just PCs one needs to worry about - as FAT getting rid of it isn't going to happen any time soon, if it all.

All your efforts to fix the patent issue are moot if you can't get Apple, MS and all the dozens and dozens of camera and PDA/smart phone manufacturers out there to support it.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 17:33 UTC (Thu) by marcH (subscriber, #57642) [Link] (2 responses)

If the patent is threatening PCs I cannot see how it does not threaten these dozens and dozens of manufacturers the same.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 2, 2009 18:08 UTC (Thu) by PO8 (guest, #41661) [Link] (1 responses)

Because device vendors license the patents, at least if Microsoft bugs them to. One reason Microsoft went after TomTom so hard is that they didn't want to give other device vendors the impression that they could let their licensing slide.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 0:46 UTC (Fri) by Ze (guest, #54182) [Link]

>>Because device vendors license the patents, at least if Microsoft bugs them to. One reason Microsoft went after TomTom so hard is that they didn't want to give other device vendors the impression that they could let their licensing slide.

The way I see it, Microsoft went after TomTom knowing that it was highly unlikely they would take it to court. TomTom is a reasonably big name though ,so they get a bit of pseudo-creditability in other peoples eyes , that don't understand the fact that TomTom was too broke to take it to court.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 3:06 UTC (Fri) by jamesh (guest, #1159) [Link]

Microsoft implemented long filename support before FAT32, and I don't believe it significantly changed with the move to FAT32.

As for a replacement for FAT, there is movement towards the exFAT file system for e.g. the successor to SDHC cards. It doesn't provide a combined long/short file name namespace, but I'm sure Microsoft has other patents on that format :(

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 13:25 UTC (Fri) by epa (subscriber, #39769) [Link]

First off, it's not FAT12 or FAT16 that's the issue, it's FAT32 and its long file name support.

FAT16 also supports long filenames under Windows 95. (FAT32 was not introduced until Windows 95 OEM Service Release 2, I think.) The mechanism for adding long filenames to the DOS filesystem (whether FAT16 or FAT32, or even FAT12 on a floppy disk) is called VFAT.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 3, 2009 1:46 UTC (Fri) by rickmoen (subscriber, #6943) [Link]

I just thought I'd puts an upper bound to the duration for which these weak patents can be even arguably relevant. Of the three patents concerning long filenames on FAT32, #5579517's earliest filing date was April 1, 1993 (being a continuation of abandoned application #41497), #5758352's earliest filing date was the same for the same reason, and #6256642's earliest filing date was Jan. 29, 1992. In the event that the "continuation from earlier applications" isn't the relevant earliest filing date specified in current US patent law (as I'm not a patent or any other type of attorney), then the actual filing dates for the cited patents are: April 24, 1995, Sept. 5, 1996, and Jan. 29, 1992, respectively.

So, these patents will be all gone by either April 1, 2013 or Sept 5, 2016, depending -- four or seven years from now.

(USPTO has special situations where applicants can get patents extended, but they don't seem to apply, here.)

Rick Moen
rick@linuxmafia.com

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 4, 2009 22:53 UTC (Sat) by djreedps (guest, #50980) [Link] (1 responses)

I posted comments in various places when SuSE was cozying up to Microsoft a few years ago and then when Linspire (remember them?) did the same, that Microsoft is not to be trusted. I was right.

I also told some Canadians on a cruise ship when the United States was going to war with Iraq in 2003 that although I was from Texas that I didn't think there was proof that Saddam Hussein had weapons of mass destruction and that we should not be bombing Iraq. I was right.

So just listen to me. You won't go wrong.

TomTom Settlement Aftermath: Get the FAT Out (Groklaw)

Posted Apr 11, 2009 4:38 UTC (Sat) by dirtyepic (guest, #30178) [Link]

Amazing.

Do you do children's parties?

My solution

Posted Apr 10, 2009 0:17 UTC (Fri) by spitzak (guest, #4593) [Link]

The patent covers *creating* filenames that don't match the 8.3 pattern. You can read them all you want. You can also delete them (one of the design criteria for VFAT was that old machines delete correctly, so it cannot possibly violate the patent).

Linux could make its own method of making "long filenames", probably a hidden file. It could read both the XFAT names and this new hidden file when listing and finding the files on the disk. If a new file was created that did not match the 8.3 pattern then it would create a new 8.3 standin name and add the name to the hidden file.

All FAT removable media would look fine on any Linux machine. But you put it into a Windows machine and suddenly some of the long filenames are wrong, truncated to an 8.3 version!

Just to cause Microsoft additional trouble, it should probably assume that any bytes are legal in the 8.3 names, thus lower-case letters and punctuation can go into them. This would screw up Windows machines reading the disk even more, certainly some ancient code in there is making assumptions that are not true.

These techniques have been used by Microsoft to attack competitors for decades, but it is possible they will work in reverse here.

PS: For the vast majority of users of cameras, etc, it won't make any difference. They only write 8.3 names. Where it will screw Microsoft up is if phones and things where users can name their files start doing this and start accepting standard removable media.