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From 9eadef5817e22891efc509ff1af6f0d14545b2b0 Mon Sep 17 00:00:00 2001
From: David Gibson <dgibson@redhat.com>
Date: Wed, 9 Sep 2015 02:03:04 +0200
Subject: spapr: Reduce advertised max LUNs for spapr_vscsi

Patchwork-id: 67711
O-Subject: [RHEL7.2 qemu-kvm-rhev PATCH] spapr: Reduce advertised max LUNs for spapr_vscsi
Bugzilla: 1260464
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>

The implementation of the PAPR paravirtual SCSI adapter currently
allows up to 32 LUNs (max_lun == 31).  However the adapter isn't really
designed to support lots of devices - the PowerVM implementation only
ever puts one disk per vSCSI controller.

More specifically, the Linux guest side vscsi driver (the only one we
really care about) is hardcoded to allow a maximum of 8 LUNs.

So, reduce the number of LUNs on the qemu side to 8, so we don't
falsely advertise that more LUNs can work.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Signed-off-by: David Gibson <dgibson@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
(cherry picked from commit 6c166e382c232ba4e527b4fc5ca9fdea151498d9)
---
 hw/scsi/spapr_vscsi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/scsi/spapr_vscsi.c b/hw/scsi/spapr_vscsi.c
index 55ee48c..92a3de3 100644
--- a/hw/scsi/spapr_vscsi.c
+++ b/hw/scsi/spapr_vscsi.c
@@ -1178,7 +1178,7 @@ static const struct SCSIBusInfo vscsi_scsi_info = {
     .tcq = true,
     .max_channel = 7, /* logical unit addressing format */
     .max_target = 63,
-    .max_lun = 31,
+    .max_lun = 7,
 
     .transfer_data = vscsi_transfer_data,
     .complete = vscsi_command_complete,
-- 
1.8.3.1