[libvirt] [PATCH v2 05/11] qemu: handle libvirtd restart after host usb device unplug

[Nikolay Shirokovskiy]

It is possible for libvirtd to go down before DEVICE_DELETED event is
delivered upon usb hostdev unplug and to receive the event after the
libvirtd is up. In order to handle this case we need to save
usb hostdev deleteAction is status file.

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy at virtuozzo.com>
---
 src/conf/domain_conf.c | 26 ++++++++++++++++++++++++++
 src/conf/domain_conf.h |  1 +
 src/qemu/qemu_driver.c | 20 ++++++++++++++++++--
 3 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index b7a342bb91..c200af050c 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1236,6 +1236,13 @@ VIR_ENUM_IMPL(virDomainShmemModel,
               "ivshmem-doorbell",
 );
 
+VIR_ENUM_IMPL(virDomainHostdevDeleteAction,
+              VIR_DOMAIN_HOSTDEV_DELETE_ACTION_LAST,
+              "none",
+              "delete",
+              "unplug"
+);
+
 VIR_ENUM_IMPL(virDomainLaunchSecurity,
               VIR_DOMAIN_LAUNCH_SECURITY_LAST,
               "",
@@ -7533,6 +7540,7 @@ virDomainHostdevSubsysUSBDefParseXML(xmlNodePtr node,
     virDomainHostdevSubsysUSBPtr usbsrc = &def->source.subsys.u.usb;
     VIR_AUTOFREE(char *) startupPolicy = NULL;
     VIR_AUTOFREE(char *) autoAddress = NULL;
+    VIR_AUTOFREE(char *) deleteAction = NULL;
 
     if ((startupPolicy = virXMLPropString(node, "startupPolicy"))) {
         def->startupPolicy =
@@ -7550,6 +7558,18 @@ virDomainHostdevSubsysUSBDefParseXML(xmlNodePtr node,
             usbsrc->autoAddress = true;
     }
 
+    if ((deleteAction = virXMLPropString(node, "deleteAction"))) {
+        def->deleteAction =
+            virDomainHostdevDeleteActionTypeFromString(deleteAction);
+
+        if (def->deleteAction <= 0) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                           _("Unknown deleteAction '%s'"),
+                           deleteAction);
+            goto out;
+        }
+    }
+
     /* Product can validly be 0, so we need some extra help to determine
      * if it is uninitialized*/
     got_product = false;
@@ -24905,6 +24925,12 @@ virDomainHostdevDefFormatSubsys(virBufferPtr buf,
 
         if (def->missing && !(flags & VIR_DOMAIN_DEF_FORMAT_INACTIVE))
             virBufferAddLit(buf, " missing='yes'");
+
+        if (def->deleteAction && (flags & VIR_DOMAIN_DEF_FORMAT_STATUS)) {
+            const char *deleteAction;
+            deleteAction = virDomainHostdevDeleteActionTypeToString(def->deleteAction);
+            virBufferAsprintf(buf, " deleteAction='%s'", deleteAction);
+        }
     }
 
     if (def->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI &&
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 19a5b21462..df88790ac0 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -338,6 +338,7 @@ typedef enum {
 
     VIR_DOMAIN_HOSTDEV_DELETE_ACTION_LAST
 } virDomainHostdevDeleteActionType;
+VIR_ENUM_DECL(virDomainHostdevDeleteAction);
 
 
 /* basic device for direct passthrough */
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index ce41b0a8d9..f1802b5d44 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -5272,10 +5272,13 @@ processUSBAddedEvent(virQEMUDriverPtr driver,
 {
     virDomainHostdevDefPtr hostdev;
     virDomainHostdevSubsysUSBPtr usbsrc;
+    virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
     size_t i;
 
-    if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
+    if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) {
+        virObjectUnref(cfg);
         return;
+    }
 
     if (!virDomainObjIsActive(vm)) {
         VIR_DEBUG("Domain is not running");
@@ -5300,8 +5303,13 @@ processUSBAddedEvent(virQEMUDriverPtr driver,
     if (qemuDomainAttachHostDevice(driver, vm, hostdev) < 0)
         goto cleanup;
 
+    if (virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm, driver->caps) < 0)
+        VIR_WARN("unable to save domain status after plugging device %s",
+                 hostdev->info->alias);
+
  cleanup:
     qemuDomainObjEndJob(driver, vm);
+    virObjectUnref(cfg);
 }
 
 
@@ -5313,9 +5321,12 @@ processUSBRemovedEvent(virQEMUDriverPtr driver,
     size_t i;
     virDomainHostdevDefPtr hostdev;
     virDomainDeviceDef dev = { .type = VIR_DOMAIN_DEVICE_HOSTDEV };
+    virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
 
-    if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
+    if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) {
+        virObjectUnref(cfg);
         return;
+    }
 
     if (!virDomainObjIsActive(vm)) {
         VIR_DEBUG("Domain is not running");
@@ -5348,8 +5359,13 @@ processUSBRemovedEvent(virQEMUDriverPtr driver,
     if (qemuDomainDetachDeviceLive(vm, &dev, driver, true, true) < 0)
         goto cleanup;
 
+    if (virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm, driver->caps) < 0)
+        VIR_WARN("unable to save domain status after unplugging device %s",
+                 hostdev->info->alias);
+
  cleanup:
     qemuDomainObjEndJob(driver, vm);
+    virObjectUnref(cfg);
 }
 
 
-- 
2.23.0