Ordered block writes

Jeremy Fitzhardinge (jeremy@zip.com.au)
Sun, 01 Feb 1998 12:32:02 +1100

Hi all,

It looks like a number of people are playing with new filesystems again.

I'm starting to play around with a transaction-based filesystem which
I'm hoping will turn up some interesting results. The first hurdle I've
found is that I need to have ordered writes, which the existing vfs
layer doesn't support. I noticed in various old mailing list archives
that this issue has been raised before, and Dave Miller said it was
being worked on. Are there any patches which add write ordering to

As an alternative, I could do with giving the filesystem some control
over its own syncing. sys_sync() just goes off and writes all dirty
things, without regard to order or consulting the filesystems. My
filesystem doesn't have detailed order dependency information, but there
is a single block write which commits all other changes, and it must
(obviously) happen after all other writes are on disk. A sync()
super_operations entry would help, which would let the filesystem set
its own write orders.

Any help/hints/pointers/suggestions?