Hello,

  I was thinking a bit about the problem and marking inode bad. I think
in the case when user is over quota marking inode as bad in not clean wrt
the filesystem so I've chosen a different solution. I've created a new flag
S_NOQUOTA which says that inode shouldn't be counted to quota (actually
we already have such inodes - quota files). This way I solved the problem
and as a bonus I got rid of testing whether inode isn't quotafiles :).
  Any comments or ideas?

								Honza

PS: The patch is attached.