Re: Interface for SCSI transactions ?

[Thomas Schmitt]

Hi,

my second try ot install of GNU/Hurd on kvm obviously succeeded. :))
I am able to download and build GNU xorriso-1.1.5.tar.gz (without
CD drive capabilities).
So far so good.


Now i face the task of modifying both sides of the RPC gap, in order
to get a transport for SCSI commands and their replies to and from
CD, DVD, or BD drives.

The plan sketched a few months ago was to extend device_get_status()
for this, because it already provides two-way transmission of an
integer array. One would have to create a new dev_flavor_t value,
which indicates that dev_status_t status actually contains a serialized
struct sdata for parameter buffer of
  int scsi_ioctl_send_command(Scsi_Device *dev, void *buffer)

I still have to find out where the RPC from device_get_status()
arrives and how to perform scsi_ioctl_send_command() on that side
of the gap.

Even if i had a detailed plan of what to code where, i still lack of
an idea how the development cycle for a kernel change would look like.

As userland programmer i feel apt to deal with the requirements of
  users-guide/using_gnuhurd.html#Helping-Out
But i never did development work inside kernels. In contrary i always
took much care not to alter the system as side effect of my work. :))


So some guidance would be highly welcome. Both with making a plan
for the code changes, and with getting a running system that implements
these changes.
(Well, if somebody shows mercy and implements it, then i would happily
 test and make use of it. Probably this would be the lesser effort
 in comparison to making me apt for kernel development.)

Will a 3 GB "disk" suffice ? Shall i install Hurd to a larger one ?

I will then have more fun with trying to get a real CD drive
working under control of libburn on a virtual Hurd.

In the meantime, i'll try to learn more about ACL and Extended Attributes
on Hurd.


Have a nice day :)

Thomas