[ANNOUNCE] Initial release of tcm_loop.ko virtual SCSI fabric module TCM Core 3.2

["Nicholas A. Bellinger" <nab@linux-iscsi.org>]

Greetings all,

I am happy to announce the first release of the tcm_loop.ko virtual SCSI
fabric module for TCM Core v3.2 that provides CDB-level SPC-3 and above
emulation for SAS Target and Initiator Port Addresses.  This allows
virtual TCM storage objects like BLOCK, FILEIO and RAMDISK to be
presented as locally accessable Linux/SCSI devices (/dev/sdz) using CDB
level emulation capable of TCM/LIO v3.2 T10 NAA WWN naming, Persistent
Reservations, and ALUA logic.

So far, sg_persist is able to span reservations between multiple
emulated SAS I_T Nexues, as well as across iSCSI Target Ports for the
same TCM backend storage object.  Also, the ability to pass the locally
accessable TCM_Loop virtual SCSI luns using scsi_generic SG_IO
passthrough into VM guests of different operating systems (RHEL5 and
NetBSD5 for example) is also up and running on top of the vmw6
hypervisor mpt-fusion HBA emulation on a Linux v2.6.32-rc5 host.

For more information and screenshots, please see:

http://linux-iscsi.org/index.php/TCM_loop

Here is the original running commit for the kernel piece:

http://git.kernel.org/?p=linux/kernel/git/nab/lio-core-2.6.git;a=commitdiff;h=10eae38203a01a26fca3b2097f13e48a0ba2d38f

And the tcm_loop.py CLI commit:

http://git.kernel.org/?p=linux/storage/lio/lio-utils.git;a=commitdiff;h=564dcf1733bb8591f02900c644f0694e1fb2af35

There is still some of work to be done in tcm_loop_configfs.c, and the
struct scsi_host_template for the emulated SCSI LLD is pretty much just
queuecommand() and proc() currently, so it needs TMR LUN_RESET.  Also
can_queue needs to be ramped up to 32 and ENABLE_CLUSTERING set, and so
far the tcm_loop virtual SCSI LUNs are able to pass simple badblocks
tests, and able to push bulk I/O.

Thanks!

--nab