[Yaffs] "!!!! Allocator out !!!!" problems

Hi,

I am using SLC nand 2gb flash using yaffs as fs .
While trying to experiment with copying I filled the entire flash (used
multi file copying).
df -k usage shows 100% ,but whenever I am trying to delete any files, I am
getting the error like

yaffs tragedy: no more eraased blocks
!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!

I feel Garbage collector has done its bit to collect all the dirty pages of
block and tried to get as many blocks as necessary to copy.
But after certain case, it has not even got a single block which has dirty
page ,hence virtually flash is full hence copy should fail.
But I am not understanding why freeing the space should fail.
Does yaffs needs atleast two partitions because I am creating single root
patition for entire flash?

Please can somebody help to pinpoint where the problem can be ?


Rgds,
Sharanu