Re: [PATCH 14/38] fallthru: ext2 fallthru support

[Miklos Szeredi <miklos@szeredi.hu>]

On Tue, 17 Aug 2010, Valerie Aurora wrote:
> >  - hard links to make sure a separate inode is not necessary for each
> >    whiteout/fallthrough entry
> 
> The problem with hard links is that you run into hard link limits.  I
> don't think we can do hard links for whiteouts and fallthrus.  Each
> whiteout or fallthru will cost an inode if we implement them as
> extended attributes.  This cost has to be balanced against the cost of
> implementing them as dentries, which is mainly code complexity in
> individual file systems.

get_unlinked_inode() is a great idea.  But I feel that individual
inodes for each fallthrough is excessive.  It'll make the first
readdir() really really expensive and wastes a lot of disk and memory
for no good reason.

Not sure how to fix the hard link limits problem though...

Thanks,
Miklos