On Tue, Mar 20, 2018 at 04:09:08PM -0600, Scott Bauer wrote: > On Tue, Mar 20, 2018 at 10:36:04AM +0100, Jonas Rabenstein wrote: > > On Mon, Mar 19, 2018 at 08:52:24PM +0100, Christoph Hellwig wrote: > > > On Mon, Mar 19, 2018 at 07:36:50PM +0100, Jonas Rabenstein wrote: > > > > Allow modification of the shadow mbr. If the shadow mbr is not marked as > > > > done, this data will be presented read only as the device content. Only > > > > after marking the shadow mbr as done and unlocking a locking range the > > > > actual content is accessible. > > > > > > I hate doing this as an ioctls. Can we make this a sysfs binary file > > > so that people can use dd or cat to write the shadow mbr? > > I already thought about providing a sysfs interface for all that instead > > of using ioctls. But as I am pretty new to kernel programming I do not > > have all the required insight. Especially, as writing the mbr requires > > the sed-opal password I am unsure how a clean sysfs interface to provide > > the password together with a simple dd would look like. > > Moreover I already have a patch that changes the 'void *data' argument > > to setup_opal_dev to a kobject pointer. As far as I know, this is the > > first step to get into the sysfs hierarchy. But as I do not have access > > to an NVMe drive and have no idea about its implementation, this change > > works only for the scsi side. > > Post what you have as an RFC (review for comment) and I will test for the NVMe > side, and or start a port for NVMe. It doesn't have to be perfect since you're > sending it out as RFC. It's just a base for us to test/look at to see if we > still like the sysfs way. Seems, like I failed to make my point in the previous message. I do not have more than adding a directory 'sed_opal' in sysfs for each sed-opal enabled disk. But that directory is completely empty. My further plans are, to fill up that directory with some public info like the one that gets printed by a call to TCG's 'sedutil-cli --query' command. The interesting part - where I am clueless how to achieve it - would be to have a binary sysfs attribute (like mentioned by Christoph) for the features (like shadow mbr) requiring some kind of authentication. Until there is any (good) idea, I do not think it is time for an RFC? -- Jonas
