I was using Ubuntu 17.10 (not installing packages, just web browsing), when I realized I could not write any data to the disk. If I typed
touch filename I received this error (paraphrasing)
Unable to write to a read-only filesystem.
I then shutdown the system. Now, on boot, I can no longer reach the grub screen. I can't get past the motherboard's disk selection screen. Occasionally, I'll see an error related to UEFI appear but it disappears to quickly to read the full message.
The (possibly) damaged drive is still listed as a block device.
If I boot to a LiveUSB and attempt to mount the filesystem
mount /dev/sda /mnt/corrupted I get the error "can't read superblock on /dev/sda".
If it matters, I don't need a full disk recovery. I only need my
Documents folder from the drive. I'm fine with losing everything else.