From 19d06bcb3c64662d5c131a035146d2caa8c5a437 Mon Sep 17 00:00:00 2001
From: Michal Privoznik <mprivozn@redhat.com>
Date: Tue, 14 Apr 2020 11:18:02 +0200
Subject: [PATCH 4/8] qemu: Revoke access to mirror on failed blockcopy

When preparing to do a blockcopy, the mirror image is modified so
that QEMU can access it. For instance, the mirror has seclabels
set, if it is a NVMe disk it is detached from the host and so on.
And usually, the restore is done upon successful finish of the
blockcopy operation. But, if something fails then we need to
explicitly revoke the access to the mirror image (and thus
reattach NVMe disk back to the host).

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1822538

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Mores <pmores@redhat.com>
(cherry-picked from commit 67e19fc9)
Signed-off-by: AlexChen <alex.chen@huawei.com>
---
 src/qemu/qemu_driver.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 8bc5368b2f..7162875492 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -17972,6 +17972,7 @@ qemuDomainBlockCopyCommon(virDomainObjPtr vm,
     virDomainDiskDefPtr disk = NULL;
     int ret = -1;
     bool need_unlink = false;
+    bool need_revoke = false;
     g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
     const char *format = NULL;
     bool mirror_reuse = !!(flags & VIR_DOMAIN_BLOCK_COPY_REUSE_EXT);
@@ -18146,6 +18147,7 @@ qemuDomainBlockCopyCommon(virDomainObjPtr vm,
 
     if (qemuDomainStorageSourceChainAccessAllow(driver, vm, mirror) < 0)
         goto endjob;
+    need_revoke = true;
 
     if (blockdev) {
         if (mirror_reuse) {
@@ -18254,14 +18256,17 @@ qemuDomainBlockCopyCommon(virDomainObjPtr vm,
 
  endjob:
     if (ret < 0 &&
-        virDomainObjIsActive(vm) &&
-        (data || crdata)) {
-        qemuDomainObjEnterMonitor(driver, vm);
-        if (data)
-            qemuBlockStorageSourceChainDetach(priv->mon, data);
-        if (crdata)
-            qemuBlockStorageSourceAttachRollback(priv->mon, crdata->srcdata[0]);
-        ignore_value(qemuDomainObjExitMonitor(driver, vm));
+        virDomainObjIsActive(vm)) {
+        if (data || crdata) {
+            qemuDomainObjEnterMonitor(driver, vm);
+            if (data)
+                qemuBlockStorageSourceChainDetach(priv->mon, data);
+            if (crdata)
+                qemuBlockStorageSourceAttachRollback(priv->mon, crdata->srcdata[0]);
+            ignore_value(qemuDomainObjExitMonitor(driver, vm));
+        }
+        if (need_revoke)
+            qemuDomainStorageSourceChainAccessRevoke(driver, vm, mirror);
     }
     if (need_unlink && virStorageFileUnlink(mirror) < 0)
         VIR_WARN("%s", _("unable to remove just-created copy target"));
-- 
2.23.0