Re: [RFC]: 64 bit LUN/Tags, dummy device in host_queue, host_lock <-> LLDD reentrancy

James Bottomley
2002-08-26T19:01:00Z

andmike@us.ibm.com said:
> James I do not follow the usage of LUNs linked by pointers, can you
> explain further?

Yes: the mid-layer could function only with Scsi_Devices and Scsi_Hosts.
LUNs are currently only used explicitly for scanning. However, I'd like to
make the error handler handle the consequences of its action, thus it will
need to know LUN relationships to handle a BDR correctly. However, the mid
layer doesn't need an arbitrary number associated with LUN or PUN. Since the
number, string or whatever is only really useful to the lld. So, simply put,
we'd probably have an entry in the Scsi_Device for lun_list. This would be
the usual doubly linked list so starting with any Scsi_Device we could always
find the associated LUNs.

James