$ dd if=/dev/zero of=qqq bs=1M count=40
$ mkfs.reiserfs -f qqq
ReiserFS is successfully created on qqq.
$ mountlo-0.6 qqq ~/mnt/tmp
$ cat /dev/frandom > ~/mnt/tmp/qqq
cat: write error: No space left on device
$ df ~/mnt/tmp/
Filesystem 1K-blocks Used Available Use% Mounted on
mountlo#qqq 40952 40952 0 100% /home/vi/mnt/tmp
$ killall mountlo-0.6
$ reiserfsck --rebuild-tree qqq
####### Pass 1 #######
Looking for allocable blocks .. finished
0%....20%....40%....60%.Not enough allocable blocks, checking bitmap...there are 1 allocable blocks, btw
out of disk space
Aborted
How to recover the filesystem now? In order to rebuild tree I need to enlarge the partition. In order to enlarge partition I need to make it clean. In order to make clean I need to use reiserfsck; and finally reiserfsck offers rebuilding the tree.
How to rebuild tree to other device (or just save all the data to another partition)?