[libvirt] [PATCH v2 1/3] qemu: hotplug: Introduce hot plug support for mediated devices

Erik Skultety posted 3 patches 7 years, 1 month ago
Only 1 patches received!
[libvirt] [PATCH v2 1/3] qemu: hotplug: Introduce hot plug support for mediated devices
Posted by Erik Skultety 7 years, 1 month ago
Mediated devices support hot-{plug,unplug} since their introduction in
kernel 4.10, however libvirt has still been missing support for this.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
---
 src/qemu/qemu_hotplug.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index 49af4d4ff..92e4d1cc9 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -2567,6 +2567,88 @@ qemuDomainAttachSCSIVHostDevice(virQEMUDriverPtr driver,
 }
 
 
+static int
+qemuDomainAttachMediatedDevice(virQEMUDriverPtr driver,
+                               virDomainObjPtr vm,
+                               virDomainHostdevDefPtr hostdev)
+{
+    int ret = -1;
+    char *devstr = NULL;
+    bool added = false;
+    bool teardowncgroup = false;
+    bool teardownlabel = false;
+    bool teardowndevice = false;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    virDomainDeviceDef dev = { VIR_DOMAIN_DEVICE_HOSTDEV,
+                                { .hostdev = hostdev } };
+
+    if (qemuDomainEnsurePCIAddress(vm, &dev, driver) < 0)
+        return -1;
+
+    if (qemuHostdevPrepareMediatedDevices(driver,
+                                          vm->def->name,
+                                          &hostdev,
+                                          1) < 0)
+        goto cleanup;
+    added = true;
+
+    if (qemuDomainNamespaceSetupHostdev(vm, hostdev) < 0)
+        goto cleanup;
+    teardowndevice = true;
+
+    if (qemuSetupHostdevCgroup(vm, hostdev) < 0)
+        goto cleanup;
+    teardowncgroup = true;
+
+    if (qemuSecuritySetHostdevLabel(driver, vm, hostdev) < 0)
+        goto cleanup;
+    teardownlabel = true;
+
+    if (qemuAssignDeviceHostdevAlias(vm->def, &hostdev->info->alias, -1) < 0)
+        goto cleanup;
+
+    if (!(devstr = qemuBuildHostdevMediatedDevStr(vm->def, hostdev,
+                                                  priv->qemuCaps)))
+        goto cleanup;
+
+    if (VIR_REALLOC_N(vm->def->hostdevs, vm->def->nhostdevs + 1) < 0)
+        goto cleanup;
+
+    qemuDomainObjEnterMonitor(driver, vm);
+    ret = qemuMonitorAddDevice(priv->mon, devstr);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0) {
+        ret = -1;
+        goto cleanup;
+    }
+
+    virDomainAuditHostdev(vm, hostdev, "attach", ret == 0);
+    if (ret < 0)
+        goto cleanup;
+
+    VIR_APPEND_ELEMENT_INPLACE(vm->def->hostdevs, vm->def->nhostdevs, hostdev);
+    ret = 0;
+ cleanup:
+    if (ret < 0) {
+        if (teardowncgroup && qemuTeardownHostdevCgroup(vm, hostdev) < 0)
+            VIR_WARN("Unable to remove host device cgroup ACL on hotplug fail");
+        if (teardownlabel &&
+            qemuSecurityRestoreHostdevLabel(driver, vm, hostdev) < 0)
+            VIR_WARN("Unable to restore host device labelling on hotplug fail");
+        if (teardowndevice &&
+            qemuDomainNamespaceTeardownHostdev(vm, hostdev) < 0)
+            VIR_WARN("Unable to remove host device from /dev");
+        if (added)
+            qemuHostdevReAttachMediatedDevices(driver,
+                                               vm->def->name,
+                                               &hostdev,
+                                               1);
+        qemuDomainReleaseDeviceAddress(vm, hostdev->info, NULL);
+    }
+    VIR_FREE(devstr);
+    return ret;
+}
+
+
 int
 qemuDomainAttachHostDevice(virQEMUDriverPtr driver,
                            virDomainObjPtr vm,
@@ -2602,6 +2684,10 @@ qemuDomainAttachHostDevice(virQEMUDriverPtr driver,
         if (qemuDomainAttachSCSIVHostDevice(driver, vm, hostdev) < 0)
             goto error;
         break;
+    case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_MDEV:
+        if (qemuDomainAttachMediatedDevice(driver, vm, hostdev) < 0)
+            goto error;
+        break;
 
     default:
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
-- 
2.14.3

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[libvirt] [PATCH v2 2/3] qemu: hotplug: Introduce hot unplug for mediated devices
Posted by Erik Skultety 7 years, 1 month ago
Mediated devices support hot-{plug,unplug} since their introduction in
kernel 4.10, however libvirt has still been missing support for this.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
---
 src/qemu/qemu_hotplug.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index 92e4d1cc9..ea94f7d2b 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -4030,6 +4030,17 @@ qemuDomainRemoveSCSIVHostDevice(virQEMUDriverPtr driver,
     qemuHostdevReAttachSCSIVHostDevices(driver, vm->def->name, &hostdev, 1);
 }
 
+
+static void
+qemuDomainRemoveMediatedDevice(virQEMUDriverPtr driver,
+                               virDomainObjPtr vm,
+                               virDomainHostdevDefPtr hostdev)
+{
+    qemuHostdevReAttachMediatedDevices(driver, vm->def->name, &hostdev, 1);
+    qemuDomainReleaseDeviceAddress(vm, hostdev->info, NULL);
+}
+
+
 static int
 qemuDomainRemoveHostDevice(virQEMUDriverPtr driver,
                            virDomainObjPtr vm,
@@ -4132,6 +4143,7 @@ qemuDomainRemoveHostDevice(virQEMUDriverPtr driver,
         qemuDomainRemoveSCSIVHostDevice(driver, vm, hostdev);
         break;
     case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_MDEV:
+        qemuDomainRemoveMediatedDevice(driver, vm, hostdev);
         break;
     case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_LAST:
         break;
@@ -5059,6 +5071,32 @@ qemuDomainDetachSCSIVHostDevice(virQEMUDriverPtr driver,
     return ret;
 }
 
+
+static int
+qemuDomainDetachMediatedDevice(virQEMUDriverPtr driver,
+                               virDomainObjPtr vm,
+                               virDomainHostdevDefPtr detach)
+{
+    int ret = -1;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+
+    if (!detach->info->alias) {
+        virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+                       _("device cannot be detached without a device alias"));
+        return -1;
+    }
+
+    qemuDomainMarkDeviceForRemoval(vm, detach->info);
+
+    qemuDomainObjEnterMonitor(driver, vm);
+    ret = qemuMonitorDelDevice(priv->mon, detach->info->alias);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
+
+    return ret;
+}
+
+
 static int
 qemuDomainDetachThisHostDevice(virQEMUDriverPtr driver,
                                virDomainObjPtr vm,
@@ -5082,6 +5120,9 @@ qemuDomainDetachThisHostDevice(virQEMUDriverPtr driver,
     case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI_HOST:
         ret = qemuDomainDetachSCSIVHostDevice(driver, vm, detach);
         break;
+    case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_MDEV:
+        ret = qemuDomainDetachMediatedDevice(driver, vm, detach);
+        break;
     default:
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("hot unplug is not supported for hostdev subsys type '%s'"),
@@ -5111,6 +5152,7 @@ int qemuDomainDetachHostDevice(virQEMUDriverPtr driver,
     virDomainHostdevSubsysUSBPtr usbsrc = &subsys->u.usb;
     virDomainHostdevSubsysPCIPtr pcisrc = &subsys->u.pci;
     virDomainHostdevSubsysSCSIPtr scsisrc = &subsys->u.scsi;
+    virDomainHostdevSubsysMediatedDevPtr mdevsrc = &subsys->u.mdev;
     virDomainHostdevDefPtr detach = NULL;
     int idx;
 
@@ -5159,6 +5201,11 @@ int qemuDomainDetachHostDevice(virQEMUDriverPtr driver,
             }
             break;
         }
+        case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_MDEV:
+            virReportError(VIR_ERR_DEVICE_MISSING,
+                           _("mediated device '%s' not found"),
+                           mdevsrc->uuidstr);
+            break;
         case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI_HOST:
             break;
         default:
-- 
2.14.3

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[libvirt] [PATCH v2 3/3] news: Update release news with mediated devices hot {plug, unplug}
Posted by Erik Skultety 7 years, 1 month ago
Signed-off-by: Erik Skultety <eskultet@redhat.com>
---
 docs/news.xml | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/docs/news.xml b/docs/news.xml
index 108889574..5f41208c2 100644
--- a/docs/news.xml
+++ b/docs/news.xml
@@ -92,6 +92,16 @@
           previously started domains to 256, or restart them.
         </description>
       </change>
+      <change>
+        <summary>
+          qemu: Support hot plug and hot unplug of mediated devices
+        </summary>
+        <description>
+          Libvirt now allows mediated devices to be hot plugged and hot
+          unplugged from a guest rather than reporting an error that this isn't
+          supported. In fact, kernel has been supporting this since 4.10.
+        </description>
+      </change>
     </section>
     <section title="Bug fixes">
     </section>
-- 
2.14.3

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  • [libvirt] [PATCH v2 1/3] qemu: hotplug: Introduce hot plug support for mediated devices