unknown fstype, device is busy, device already exists

i'm trying to boot an ubuntu 10.04 system with encrypted root partition, suddenly unable to. i'm typing the passphrase correctly, as i see "Key slot 1 unlocked" on the console, but it is then followed by:

cryptsetup: unknown fstype, bad password or options? Device sda5_crypt is busy.
Device sda5_crypt already exists

and then i am asked for the passphrase again. after i type it again i am told "cryptsetup failed, bad password or options?"

after a third time i receive the same message but then after about a minute i am told "no init found" and dropped to a Busybox shell.

sounds like my disk suddenly crapped out or something, what kinds of remedies are available? thanks

booted with SystemRescueCD and SMART status looks ok
(http://pastebin.com/wfZ5q5TL)
fdisk:
Disk /dev/sda: 300.1 GB, 300069052416 bytes, 586072368 sectors Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000c3127

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63      192779       96358+  83  Linux
/dev/sda2          192780   586067264   292937242+   5  Extended
/dev/sda5          192843   586067264   292937211   83  Linux

if i try to unlock /dev/sda5 it works and lvdisplay shows my logical volumes (http://pastebin.com/v9gqjchL) but when i try to mount /dev/ubuntu/root i get "special device /dev/ubuntu/root does not exist" so unsure if that is a limitation of sysrescuecd or a problem with my LVM in which case i needa move to another mailing list??

Didn't you forget to activate LVs?

Use "vgchange -a y" and try to mount them again.

Milan

Milan Broz @ 05/31/2013 11:52 PM:

thanks, yes, i did. i'm in unknown waters here! after making LVs available and trying to mount again i'm getting "NTFS signature is missing" (which makes no sense since i've never used NTFS before). if i add '-t ext3' i get "wrong fs type, bad option, bad superblock on /dev/mapper/ubuntu-root, missing codepage or helper program...." so i ran fsck and it fixed a number of errors....

bad magic number in super-block
superblock invalid, trying backup blocks....
Superblock needs_recovery flag is clear, but journal has data Recovery flag not set in backup superblock, so running journal anyway /dev/mapper/ubuntu-root: recovering journal

and then alot of things i fix... free blocks count wrong, directories count wrong, free inodes count wrong. but after fixing i am able to mount the filesystem and boot the system normally. *sigh of relief* i'm pleased the FS was able to be repaired but what caused it still irks me....