[libvirt] [PATCH v3 23/24] qemu: cancel drive mirrors when p2p connection breaks

[Jiri Denemark]

When a connection to the destination host during a p2p migration drops,
we know we will have to cancel the migration; it doesn't make sense to
waste resources by trying to finish the migration. We already do so
after sending "migrate" command to QEMU and we should do it while
waiting for drive mirrors to become ready too.

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---

Notes:
    ACKed in version 2
    
    Version 3:
    - rebased on top of modified qemuMigrationDriveMirrorCancelled
    
    Version 2:
    - new patch

 src/qemu/qemu_migration.c | 29 +++++++++++++++++++++++------
 1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 60c75f3..c53d2ea 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -1908,7 +1908,8 @@ static int
 qemuMigrationCancelDriveMirror(virQEMUDriverPtr driver,
                                virDomainObjPtr vm,
                                bool check,
-                               qemuDomainAsyncJob asyncJob)
+                               qemuDomainAsyncJob asyncJob,
+                               virConnectPtr dconn)
 {
     virErrorPtr err = NULL;
     int ret = -1;
@@ -1939,6 +1940,13 @@ qemuMigrationCancelDriveMirror(virQEMUDriverPtr driver,
     }
 
     while ((rv = qemuMigrationDriveMirrorCancelled(driver, vm, check)) != 1) {
+        if (check && !failed &&
+            dconn && virConnectIsAlive(dconn) <= 0) {
+            virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+                           _("Lost connection to destination host"));
+            failed = true;
+        }
+
         if (rv < 0) {
             failed = true;
             if (rv == -2)
@@ -1989,7 +1997,8 @@ qemuMigrationDriveMirror(virQEMUDriverPtr driver,
                          qemuMigrationCookiePtr mig,
                          const char *host,
                          unsigned long speed,
-                         unsigned int *migrate_flags)
+                         unsigned int *migrate_flags,
+                         virConnectPtr dconn)
 {
     qemuDomainObjPrivatePtr priv = vm->privateData;
     int ret = -1;
@@ -2069,6 +2078,12 @@ qemuMigrationDriveMirror(virQEMUDriverPtr driver,
             goto cleanup;
         }
 
+        if (dconn && virConnectIsAlive(dconn) <= 0) {
+            virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+                           _("Lost connection to destination host"));
+            goto cleanup;
+        }
+
         if (virDomainObjWait(vm) < 0)
             goto cleanup;
     }
@@ -3689,7 +3704,7 @@ qemuMigrationConfirmPhase(virQEMUDriverPtr driver,
 
         /* cancel any outstanding NBD jobs */
         qemuMigrationCancelDriveMirror(driver, vm, false,
-                                       QEMU_ASYNC_JOB_MIGRATION_OUT);
+                                       QEMU_ASYNC_JOB_MIGRATION_OUT, NULL);
 
         virSetError(orig_err);
         virFreeError(orig_err);
@@ -4106,7 +4121,8 @@ qemuMigrationRun(virQEMUDriverPtr driver,
             if (qemuMigrationDriveMirror(driver, vm, mig,
                                          spec->dest.host.name,
                                          migrate_speed,
-                                         &migrate_flags) < 0) {
+                                         &migrate_flags,
+                                         dconn) < 0) {
                 goto cleanup;
             }
         } else {
@@ -4265,7 +4281,8 @@ qemuMigrationRun(virQEMUDriverPtr driver,
     /* cancel any outstanding NBD jobs */
     if (mig && mig->nbd) {
         if (qemuMigrationCancelDriveMirror(driver, vm, ret == 0,
-                                           QEMU_ASYNC_JOB_MIGRATION_OUT) < 0)
+                                           QEMU_ASYNC_JOB_MIGRATION_OUT,
+                                           dconn) < 0)
             ret = -1;
     }
 
@@ -5853,7 +5870,7 @@ qemuMigrationCancel(virQEMUDriverPtr driver,
     }
 
     if (qemuMigrationCancelDriveMirror(driver, vm, false,
-                                       QEMU_ASYNC_JOB_NONE) < 0)
+                                       QEMU_ASYNC_JOB_NONE, NULL) < 0)
         goto endsyncjob;
 
     ret = 0;
-- 
2.4.3