I used sudo gainroot, but this doesn't seem to be sufficient because in step (3)

# swapoff /media/mmc2/.swap

returns: Read-only file system

ls -l .swap shows these permissions: -rw-r--r-- 1 user root

I messed up my internal flash on my N810 too. What I did was grab e2fsprogs and used sfdisk to fix it.

apt-get install e2fsprogs

Edit: Oh ya, this will erase all files you have on the 2 gig internal memory. So if your looking to restore corrupted data on it or trying to do this w/o loosing data on the internal 2 gig memory then please DONT do the following , as it will erase all data on your 2 gig internal memory.

Use all the following commands as root of course.

umount /media/mmc2
then
sfdisk /dev/mmcblk0

Now it's going to ask you for cylinder sizes for each partition (4 partitions). So for the first one,
type in 0,,b all on the same line (ex. /dev/mmcblk0p1:0,,b )
then for the next 3 just hit enter and put nothing in.

This should repartition "mmc2" to use all the cylinders. The missing number in between the commas means use the programs default, which is to make use of the remaining cylinders. You could do 0,61440,b to be precise, either way it works the same. b is the code for FAT32, if you wish to use FAT16 the code is 6

now you can do
mkdosfs /dev/mmcblk0p1
and then reboot the device. Now it should give you back your internal memory.

If that doesn't work, check that you are actualy root with whoami. Other then that I dunno what else to do, I'm not very Linux edjumakated

Alternativly, you can reboot w/o using the mkdosfs command. Once you reboot you can goto file manager and click and hold on the "Internal Memory" which should be there now and click format. OR plug it in to windows via USB and it'll ask you to format then too.

Just a general note to all, if you ever bork up or change your internal memory on the N810 (MMC2) , a re-flash will not default this memory. Reflash only reflashes the ROM; which is 256 megs or so the the OS is installed on.

The actual size of the internal flash memory is ~1.85 GB.
61440(the number of cylinders) * 31768(the ammount of bytes per cylinder) = 2013265920 B = 1.875 GB

This is how I fixed mine , results may varry.

You might be able to run fsck with it mounted. I'd only be worried about the swap file being active confusing the OS and causing problems.

Is it actually using that swap file?

If no, you'll just see the header line. Go ahead and run the umount and fsck.vfat lines.

Just curious, what shows up when you type mount?

My assumption here is you want to save the files on the internal mmc device. If not, it might be easier to start from clean. The only thing installed on there by default is the map set.

I'm a little concerned that multiple people are corrupting their internal drive.

All this skirts around the fundamental issue that it was damn stupid of Nokia to create a fixed flash card in the first place. Flash really doesn't exactly have a very good reputation for long term reliability, particularly if you are writing data to it frequently (ie a swap file). With a removeable card if something goes bad and all the Linux-foo in the world can't fix it, I can throw it out and slap another one in for $30. If the internal, soldered flash really goes bad, you are going to have to send it back to Nokia for repairs (assuming it is still under warranty). Just do a quick search of this message board to reveal how excruciating an experience that has been for most people.

Rocketman, I agree that a removable card would be better, but the N810 isn't the first relatively expensive device to include non-removable storage. Think of iPod and many other products with internal drives or flash.

So it's not an ideal situation, but hardly unique to the N810. And the N810 does still support one removable card, so you wouldn't be completely out of luck if you decided not to get it repaired.

First become the root:
http://maemo.org/community/wiki/howdoibecomeroot/

After logging in as root (in X Terminal), 'lsof /media/mmc2' should show the process having the file open on the card. Use the 'PID' number given by lsof to kill the process(es) with 'kill -9 <PID>'. After this lsof should not show any open files on the card. Make sure swapping is not on by running 'swapoff /media/mmc2/.swap' as root. Now you should be able to reformat the card in File Manager.

Can anyone confirm that the information on the Maemo wiki for Mac OSX appies to the N810? Or where else should I look for information about udating the N810 OS using Mac OSX?

Thanks

Sorry I did not adequately explain earlier that this approach fails.

lsof /media/mmc2 shows no processes running
swapoff /media/mmc2/.swap reports "Read-only file system"

cat /proc/swaps reports Used "0" which I take to mean the swapfile is not in use.

I discovered this problem after updating the operating system, but I suspect it may have occurred when I downloaded an additional GPS map, because the filename of the additional map is corrupted while the original maps look fine. In principle I wouldn't mind downloading all the maps again, but the process is slow and if it is flawed I might have no usable maps.

I can still read and copy files from the internal disk, which means I could backup the maps before reformatting. However, I would need to obtain a 2GB Mini SSD because I cannot access the Internal card via USB.

umount /media/mmc2 fails "Cannot umount /media/mmc2: Device or resource busy"