[Stgt-devel] Further problems with the SSC code ...

[Richard Sharpe]

Hi,

OK, so I tar'd up some 20GB of data to my remote virtual tape via
iSCSI etc, but the virtual tape file at the remote end only contained
10kB, the last 10kB of the tar file.

This seems to be because of deficiencies in the ssc.c etc code.

Since it uses the standard bs_thread_submit_cmd it relies on bs_rdwr.c
to do the writing and reading ... which expects an offset, but the ssc
code always supplies this as zero (since it is never sent).

Since we are dealing with a sequential device, which might, however,
be rewound or be positioned to weird block offsets, or be asked to
position to the next tape mark, this functionality needs to be in
ssc.c.

I suggest that when the LU us created we need to allocate some private
space where we will keep this information, and then, before we submit
the command, do the correct things to it.

I am going to start doing this because I need this stuff to work correctly ...