Like Mat said, you can't have partitions out of non-contiguous space, so if you want to enlarge
sda1, you need to take
sda2 out of the way.
Again, as Mat said, as
sda2 is a swap partition, there's nothing you need to keep there, so you can just get rid of it.
For short, you want/need to do as follows
sda2 out of the way
- create another swap partition
Now, for the small print and important details
- Disable the swap space before getting rid of the partition —
swapoff /dev/sda2 should do it, and after that you can get rid of
sda2 simply by removing the partition from the partition table
sda2 from the partition table using some partition table editor utility -
fdisk (here, focus on picking one you feel comfortable with — after all messing with an alien tool, such as using
gparted if you've got no clue where the options are, or
fdisk if you don't know what are the commands, is just a shortcut to get rid of your precious data (you can picture Andy Serkis saying "my precious data")
Now you have unallocated space after
sda1 — you can now enlarge the partition to 90 GB. This, if I'm not mistaken, is just changing the partition table so that it lists the new, larger size for the partition. Depending on the partitioning tool, this and the next step may be bundled in the same option/feature.
After enlarging the partition, you can finally extend/grow the filesystem which lives in the partition so that it spans the full size of the partition. This requires a filesystem-aware tool. I've been able to grow ext2/ext3 partitions from
gparted, I don't know about ext4 — if ext4 is to ext3 as ext3 is to ext2 (just additions), then I'd guess the same tool
gparted uses for ext2/ext3 should be able to handle ext4.
Finally, you can recreate your swap partition. Bonus credit if you create it as
sda2 (which should happen unless you create an extended partition), as you won't have to change your configuration files to use the new swap. Use
swapon to start using the new swap partition with no reboot.
Please note that, although all steps but 4 are (probably) possible to carry on a live system which is using the disk and has
sda1 mounted, step 4 above must be done with
sda1 unmounted. In the end, it's probably easier if you do all of it from a live CD — there is a gparted livecd, you can try that. But any other live CD should do, as far as it has the partitioning tool, the filesystem growing tool, and is recent enough to handle your hardware (unless you're using a bleeding edge northbridge or SATA controller, or trying to partition a terabyte drive from Damn Small Linux (well, maybe it actually works, I just remember the userland tools are unable to deal with >4GB files, which is a totally different issue), you shouldn't have to worry about this).