> Date: Sun, 20 Feb 2011 07:03:25 -0500 > From: Kenneth R Westerback <kwesterb...@rogers.com> > > On Sun, Feb 20, 2011 at 12:39:06PM +0100, Mark Kettenis wrote: > > > Date: Sun, 20 Feb 2011 19:54:21 +1000 > > > From: David Gwynne <l...@animata.net> > > > > > > > how to manipulate write cache policy? > > > > > > the lsi firmwares dont implement handling of the mod page changes > > > unfortunately. you could call the ioctl this implements yourself > > > though from userland. > > > > David, while I think that implementing the cache manipulation ioctls > > for mpii(4) is a good idea, there is a problem here. We don't have a > > tool in base that actually issues those ioctls. And unless I'm > > misreading the diff, this still leaves the cache disabled on the > > stupid Dell. > > DIOCSCACHE is called in sdattach() to enable write cache for all > disks that DIOCGCACHE reports as having write cache disabled. Or are > you concerned that we have no way to manipulate it from userland > if/when the default needs to be modified?
Ah, that's the bit I was missing. A userland tool to display and manipulate the cache settings would still be good though. Functionality should probably be added to bioctl(8). A bit unfortunate that both the -c and -C options are already taken.