On 1/27/23 16:51, Damien Le Moal wrote:
On 1/27/23 22:00, Hannes Reinecke wrote:
Hmm. Calling this during revalidate() makes sense, but how can we ensure
that we call revalidate() when the user issues a MODE_SELECT command?
Given that CDLs can be changed with a passthrough command, I do not think we can
do anything about that, unfortunately. But I think the same is true of many
things like that. E.g. "let's turn onf/off the write cache without the kernel
noticing"... But given that on a normal system only privileged applications can
do passthrough, if that happens, then the system has been hacked or the user is
shooting himself in the foot.
cdl-tools project (cdladm utility) uses passtrhough but triggers a revalidate
after changing CDLs to make sure sysfs stays in sync.
As Christoph suggested, we could change all this to an ioctl(GET_CDL) for
applications... But sysfs is so much simpler in my opinion, not to mention that
it allows access to the information for any application written in a language
that does not have ioctl() or an equivalent.
cdl-tools has a test suite all written in bash scripts thanks to the sysfs
interface :)
My understanding is that combining the sd driver with SCSI pass-through
is not supported and also that there are no plans to support this
combination.
Martin, please correct me if I got this wrong.
Thanks,
Bart.