[reiserfs-list] Re: [OpenAFS-devel] more on the 2.2.18pre17 SMPcpu
Vladimir V. Saveliev
Mon, 04 Dec 2000 17:03:58 +0300
Danilov Nikita wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hans Reiser writes:
> > Nikita has code not in our main branch that allows looking up files by their keys, we did it for
> > squid when writing a namefree file store for it, let's give him a chance to comment on Monday.
> if you are still interested in it, that is what was done for the
> lookup-by-key stuff:
> (*) there is ioctl to get key of open file descriptor
> (*) there is special ram-only fs (like /proc) to open files on given
> reiserfs mount by the keys.
> > Hans
> > Chris Mason wrote:
> > >
> > > On Saturday, December 02, 2000 15:33:58 -0500 Derek Atkins
> > > <warlord@MIT.EDU> wrote:
> > >
> > > > I don't know anything about reiserfs, but I can explain what AFS is
> > > > doing. Basically, the afsd user-space process does an opendir() on
> > > > the cache directory. Then it iterates through the files looking for
> > > > the cache files (they are all numbered, and the cachefile number is
> > > > stored in the filename). For each cache file, it stores the inode
> > > > number (obtained from dirp->d_ino from readdir()) associated that that
> > > > cache file number (obtained from dirp->d_name).
> So, call ioctl in stat's stead and remember key.
reiserfs_readdir could put packing locality component after 0 in dirp->d_name and set dirp->d_reclen
correspondingly for those who is aware of reiserfs tricks.