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I'm using the osdev wiki as a resource for programming an OS. So far I've got a 2 stage bootloader, with a very minimal 32-bit Protected mode kernel.

However, For the bootloader, I've been writing to a specific sector, and reading from a specific sector, and I've decided to do it the "right way", and use a file system, so I picked the ext2 file system, as the wiki has documentation on it. So I formatted my flash drive with ext2, using gparted on Ubuntu 11.10, and grabbed lde (linux disc editor), and ran it with my flash drive.

The problem is that, I don't see table as described on the ext2 page, I've looked at byte 1024 (0x400), among other places, and I can't seem to find the table. I went back into gparted, and it's still formatted. Also, lde says "unrecognized file system", even when I specify that it's ext2. Does a flash drive not use the standard ext2 file system, has the file system been changed so much that it resemble that described on the page, or am I just not looking in the right place?

Links:

Ext2 - http://wiki.osdev.org/Ext2

OsDev Wiki - http://wiki.osdev.org/Main_Page

tshepang
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codesmith
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  • I have heard that _some_ cheap flash drives use "private" space from the FAT filesystem for their own internal use, and thus can't handle using other filesystems reliably. But I'd hope those devices are no longer on the market, as they sound _horrible_. What does `debugfs(8)` say about your filesystem? – sarnold Mar 31 '12 at 00:30
  • It says : Bad magic number in super-block while opening filesystem, and they do sound horrible, hope that's not the problem here. – codesmith Mar 31 '12 at 00:50
  • Most sticks are used unpartitioned; I have no idea how well different tools will handle them if they are partitioned, but make sure you're using `/dev/sdX` or `/dev/sdX1` consistently. – sarnold Mar 31 '12 at 00:56
  • I've been using /dev/sdb the entire time, I'll try /dev/sdb1. – codesmith Mar 31 '12 at 00:57
  • That's the problem. I need to use /dev/sdb1 – codesmith Mar 31 '12 at 01:20
  • Woot. As soon as you're allowed, please write up the details in an answer. Thanks! :) – sarnold Mar 31 '12 at 01:32
  • No prob, kinda short for time tonight, but definitely in the morning (or if I get a break), I will do so. – codesmith Mar 31 '12 at 01:37

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As stated in the comments, I've answered my question. My problem wasn't with formatting my flash drive, or the way the flash drive is used, or anything else technical. The problem was that when I was using my disc editor, I told it to read the drive itself (/dev/sdb), and I needed to use the partition (/dev/sdb1). When I looked at the partition, I looked at 0x400 (the start of the superblock), and the superblock was indeed where it was supposed to be. I also compared the superblock, and several of the other blocks / inodes with the ones on my hard drive, and the format was the same, but not the data, as to be expected.

codesmith
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