From cd4c45ef3c5323053d76057a0435759ce84ede90 Mon Sep 17 00:00:00 2001
From: Fam Zheng <famz@redhat.com>
Date: Fri, 6 Jun 2014 04:11:38 +0200
Subject: [PATCH 09/13] scsi-disk: Improve error messager if can't get version number

RH-Author: Fam Zheng <famz@redhat.com>
Message-id: <1402027899-1917-2-git-send-email-famz@redhat.com>
Patchwork-id: 59163
O-Subject: [RHEL-7 qemu-kvm PATCH 1/2] scsi-disk: Improve error messager if can't get version number
Bugzilla: 1021788
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
RH-Acked-by: Amos Kong <akong@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

More often it is that bdrv_ioctl fails due to not supported by driver or
whatever reason, in this case we should be specific, because "interface
too old" is very confusing.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 4bbeb8b173e8116851d5ececb93189ae34c68309)
Signed-off-by: Fam Zheng <famz@redhat.com>
---
 hw/scsi/scsi-disk.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/scsi/scsi-disk.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index 6491091..5a6384e 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -2439,8 +2439,13 @@ static int scsi_block_initfn(SCSIDevice *dev)
     }
 
     /* check we are using a driver managing SG_IO (version 3 and after) */
-    if (bdrv_ioctl(s->qdev.conf.bs, SG_GET_VERSION_NUM, &sg_version) < 0 ||
-        sg_version < 30000) {
+    rc =  bdrv_ioctl(s->qdev.conf.bs, SG_GET_VERSION_NUM, &sg_version);
+    if (rc < 0) {
+        error_report("scsi-block: can not get version number: %s",
+                     strerror(-rc));
+        return -1;
+    }
+    if (sg_version < 30000) {
         error_report("scsi-block: scsi generic interface too old");
         return -1;
     }
-- 
1.7.1