From: AMEET M. PARANJAPE <aparanja@redhat.com>
Date: Mon, 15 Jun 2009 12:24:46 -0400
Subject: [scsi] ibmvscsi: add 16 byte CDB support
Message-id: 20090615162127.7734.77541.sendpatchset@squad5-lp1.lab.bos.redhat.com
O-Subject: [PATCH RHEL5.4 BZ502944]ibmvscsi: Add 16 byte CDB support
Bugzilla: 502944
RH-Acked-by: Mike Christie <mchristi@redhat.com>
RH-Acked-by: Stefan Assmann <sassmann@redhat.com>

RHBZ#:
======
https://bugzilla.redhat.com/show_bug.cgi?id=502944

Description:
===========
Adds support for 16 byte command descriptor blocks (CDBs) to the ibmvscsi
driver.

RHEL Version Found:
================
RHEL 5.4 KOTD (-150.el5)

kABI Status:
============
No symbols were harmed.

Brew:
=====
Built on all platforms.
http://brewweb.devel.redhat.com/brew/taskinfo?taskID=1844511

Upstream Status:
================
http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=fbc56f0801f58041a4372a030933bac076b46aad

Test Status:
============
Without this patch a PPC LPAR could not see the complete 10TB LUN:

sdb : very big device. try to use READ CAPACITY(16).
sdb : READ CAPACITY(16) failed.
sdb : status=0, message=00, host=5, driver=00
sdb : use 0xffffffff as device size
SCSI device sdb: 4294967296 512-byte hdwr sectors (2199023 MB)

[root@kent-p1 ~]# cat /proc/partitions
major minor  #blocks  name
...
8    16 2147483648 sdb

With this patch applied the complete 10TB LUN is seen:

sdb : very big device. try to use READ CAPACITY(16).
SCSI device sdb: 20504608768 512-byte hdwr sectors (10498360 MB)
===============================================================
Ameet Paranjape 978-392-3903 ext 23903
IBM on-site partner

Proposed Patch:
===============

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 93f7e65..0270ac6 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -1686,6 +1686,7 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	host->max_lun = 8;
 	host->max_id = max_id;
 	host->max_channel = max_channel;
+	host->max_cmd_len = 16;
 
 	if (scsi_add_host(hostdata->host, hostdata->dev))
 		goto add_host_failed;