qemu: Wire up <memory/> live update

As advertised in one of previous commits, we want to be able to
change 'requested-size' attribute of virtio-mem on the fly. This
commit does exactly that. Changing anything else is checked for
and forbidden.

Once guest has changed the allocation, QEMU emits an event which
we will use to track the allocation. In the next commit.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 4cbcf69bf0a50ddad76f8dbe4a30a4eb4d158be6..96d85a7610936204c032c61b76639e6eb73b1a5c 100644 (file)
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -16577,6 +16577,50 @@ virDomainMemoryFindInactiveByDef(virDomainDef *def,
 }
 
 
+/**
+ * virDomainMemoryFindByDeviceInfo:
+ * @def: domain defintion
+ * @info: device info to match
+ * @pos: store position within array
+ *
+ * For given domain definition @def find <memory/> device with
+ * matching address and matching device alias (if set in @info,
+ * otherwise ignored).
+ *
+ * If @pos is not NULL then the position of the matched device
+ * within the array is stored there.
+ *
+ * Returns: device if found,
+ *          NULL otherwise.
+ */
+virDomainMemoryDef *
+virDomainMemoryFindByDeviceInfo(virDomainDef *def,
+                                virDomainDeviceInfo *info,
+                                int *pos)
+{
+    size_t i;
+
+    for (i = 0; i < def->nmems; i++) {
+        virDomainMemoryDef *tmp = def->mems[i];
+
+        if (!virDomainDeviceInfoAddressIsEqual(&tmp->info, info))
+            continue;
+
+        /* alias, if present */
+        if (info->alias &&
+            STRNEQ_NULLABLE(tmp->info.alias, info->alias))
+            continue;
+
+        if (pos)
+            *pos = i;
+
+        return tmp;
+    }
+
+    return NULL;
+}
+
+
 /**
  * virDomainMemoryInsert:
  *
@@ -28590,7 +28634,8 @@ virDomainDefCompatibleDevice(virDomainDef *def,
             return -1;
         }
 
-        if ((virDomainDefGetMemoryTotal(def) + sz) > def->mem.max_memory) {
+        if (action == VIR_DOMAIN_DEVICE_ACTION_ATTACH &&
+            (virDomainDefGetMemoryTotal(def) + sz) > def->mem.max_memory) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            _("Attaching memory device with size '%llu' would "
                              "exceed domain's maxMemory config size '%llu'"),

diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 8356d38dcb62b3b491953a04544690f526ea9815..9db15a87fbb08d4122772f8683151b61a5aaffe5 100644 (file)
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -3807,6 +3807,11 @@ int virDomainMemoryFindByDef(virDomainDef *def, virDomainMemoryDef *mem)
 int virDomainMemoryFindInactiveByDef(virDomainDef *def,
                                      virDomainMemoryDef *mem)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT;
+virDomainMemoryDef *
+virDomainMemoryFindByDeviceInfo(virDomainDef *dev,
+                                virDomainDeviceInfo *info,
+                                int *pos)
+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT;
 
 int virDomainShmemDefInsert(virDomainDef *def, virDomainShmemDef *shmem)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) G_GNUC_WARN_UNUSED_RESULT;

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 8b29b66a11a3710654f0618b6e478b016cba0618..635f63815d5f64c3c529883f7202c48d1bca4321 100644 (file)
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -508,6 +508,7 @@ virDomainMemballoonModelTypeFromString;
 virDomainMemballoonModelTypeToString;
 virDomainMemoryDefFree;
 virDomainMemoryFindByDef;
+virDomainMemoryFindByDeviceInfo;
 virDomainMemoryFindInactiveByDef;
 virDomainMemoryInsert;
 virDomainMemoryModelTypeToString;

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 4bd79b9537a638f7c3d278cc6f970d2c5c83d401..3d0ad3870ff1349bd0add7de6e5ea9875c33fff0 100644 (file)
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -6976,6 +6976,175 @@ qemuDomainChangeDiskLive(virDomainObj *vm,
     return 0;
 }
 
+
+static bool
+qemuDomainChangeMemoryLiveValidateChange(const virDomainMemoryDef *oldDef,
+                                         const virDomainMemoryDef *newDef)
+{
+    /* The only thing that is allowed to change is 'requestedsize' for
+     * virtio-mem model. Check if user isn't trying to sneak in change for
+     * something else. */
+
+    switch (oldDef->model) {
+    case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM:
+        break;
+
+    case VIR_DOMAIN_MEMORY_MODEL_NONE:
+    case VIR_DOMAIN_MEMORY_MODEL_DIMM:
+    case VIR_DOMAIN_MEMORY_MODEL_NVDIMM:
+    case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_PMEM:
+    case VIR_DOMAIN_MEMORY_MODEL_LAST:
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory of model '%s'"),
+                       virDomainMemoryModelTypeToString(oldDef->model));
+        return false;
+        break;
+    }
+
+    if (oldDef->model != newDef->model) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory model from '%s' to '%s'"),
+                       virDomainMemoryModelTypeToString(oldDef->model),
+                       virDomainMemoryModelTypeToString(newDef->model));
+        return false;
+    }
+
+    if (oldDef->access != newDef->access) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory access from '%s' to '%s'"),
+                       virDomainMemoryAccessTypeToString(oldDef->access),
+                       virDomainMemoryAccessTypeToString(newDef->access));
+        return false;
+    }
+
+    if (oldDef->discard != newDef->discard) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory discard from '%s' to '%s'"),
+                       virTristateBoolTypeToString(oldDef->discard),
+                       virTristateBoolTypeToString(newDef->discard));
+        return false;
+    }
+
+    if (!virBitmapEqual(oldDef->sourceNodes,
+                        newDef->sourceNodes)) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("cannot modify memory source nodes"));
+        return false;
+    }
+
+    if (oldDef->pagesize != newDef->pagesize) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory pagesize from '%llu' to '%llu'"),
+                       oldDef->pagesize,
+                       newDef->pagesize);
+        return false;
+    }
+
+    if (STRNEQ_NULLABLE(oldDef->nvdimmPath, newDef->nvdimmPath)) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory path from '%s' to '%s'"),
+                       NULLSTR(oldDef->nvdimmPath),
+                       NULLSTR(newDef->nvdimmPath));
+        return false;
+    }
+
+    if (oldDef->alignsize != newDef->alignsize) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory align size from '%llu' to '%llu'"),
+                       oldDef->alignsize, newDef->alignsize);
+        return false;
+    }
+
+    if (oldDef->nvdimmPmem != newDef->nvdimmPmem) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory pmem from '%d' to '%d'"),
+                       oldDef->nvdimmPmem, newDef->nvdimmPmem);
+        return false;
+    }
+
+    if (oldDef->targetNode != newDef->targetNode) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory targetNode from '%d' to '%d'"),
+                       oldDef->targetNode, newDef->targetNode);
+        return false;
+    }
+
+    if (oldDef->size != newDef->size) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory size from '%llu' to '%llu'"),
+                       oldDef->size, newDef->size);
+        return false;
+    }
+
+    if (oldDef->labelsize != newDef->labelsize) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory label size from '%llu' to '%llu'"),
+                       oldDef->labelsize, newDef->labelsize);
+        return false;
+    }
+    if (oldDef->blocksize != newDef->blocksize) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("cannot modify memory block size from '%llu' to '%llu'"),
+                       oldDef->blocksize, newDef->blocksize);
+        return false;
+    }
+
+    /* requestedsize can change */
+
+    if (oldDef->readonly != newDef->readonly) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("cannot modify memory pmem flag"));
+        return false;
+    }
+
+    if ((oldDef->uuid || newDef->uuid) &&
+        !(oldDef->uuid && newDef->uuid &&
+          memcmp(oldDef->uuid, newDef->uuid, VIR_UUID_BUFLEN) == 0)) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("cannot modify memory UUID"));
+        return false;
+    }
+
+    return true;
+}
+
+
+static int
+qemuDomainChangeMemoryLive(virQEMUDriver *driver G_GNUC_UNUSED,
+                           virDomainObj *vm,
+                           virDomainDeviceDef *dev)
+{
+    virDomainDeviceDef oldDev = { .type = VIR_DOMAIN_DEVICE_MEMORY };
+    virDomainMemoryDef *newDef = dev->data.memory;
+    virDomainMemoryDef *oldDef = NULL;
+
+    oldDef = virDomainMemoryFindByDeviceInfo(vm->def, &dev->data.memory->info, NULL);
+    if (!oldDef) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("memory '%s' not found"), dev->data.memory->info.alias);
+        return -1;
+    }
+
+    oldDev.data.memory = oldDef;
+
+    if (virDomainDefCompatibleDevice(vm->def, dev, &oldDev,
+                                     VIR_DOMAIN_DEVICE_ACTION_UPDATE,
+                                     true) < 0)
+        return -1;
+
+    if (!qemuDomainChangeMemoryLiveValidateChange(oldDef, newDef))
+        return -1;
+
+    if (qemuDomainChangeMemoryRequestedSize(driver, vm,
+                                            newDef->info.alias,
+                                            newDef->requestedsize) < 0)
+        return -1;
+
+    oldDef->requestedsize = newDef->requestedsize;
+    return 0;
+}
+
+
 static int
 qemuDomainUpdateDeviceLive(virDomainObj *vm,
                            virDomainDeviceDef *dev,
@@ -7017,6 +7186,10 @@ qemuDomainUpdateDeviceLive(virDomainObj *vm,
         ret = qemuDomainChangeNet(driver, vm, dev);
         break;
 
+    case VIR_DOMAIN_DEVICE_MEMORY:
+        ret = qemuDomainChangeMemoryLive(driver, vm, dev);
+        break;
+
     case VIR_DOMAIN_DEVICE_FS:
     case VIR_DOMAIN_DEVICE_INPUT:
     case VIR_DOMAIN_DEVICE_SOUND:
@@ -7032,7 +7205,6 @@ qemuDomainUpdateDeviceLive(virDomainObj *vm,
     case VIR_DOMAIN_DEVICE_HOSTDEV:
     case VIR_DOMAIN_DEVICE_CONTROLLER:
     case VIR_DOMAIN_DEVICE_REDIRDEV:
-    case VIR_DOMAIN_DEVICE_MEMORY:
     case VIR_DOMAIN_DEVICE_CHR:
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_TPM:

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index 33d2dcc794f06ae23760f098af94611ae0040015..22239b26899602e70f7fdd94e510df244819c1f9 100644 (file)
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -6797,3 +6797,21 @@ qemuDomainSetVcpuInternal(virQEMUDriver *driver,
     virBitmapFree(livevcpus);
     return ret;
 }
+
+
+int
+qemuDomainChangeMemoryRequestedSize(virQEMUDriver *driver,
+                                    virDomainObj *vm,
+                                    const char *alias,
+                                    unsigned long long requestedsize)
+{
+    qemuDomainObjPrivate *priv = vm->privateData;
+    int rc;
+
+    qemuDomainObjEnterMonitor(driver, vm);
+    rc = qemuMonitorChangeMemoryRequestedSize(priv->mon, alias, requestedsize);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        return -1;
+
+    return rc;
+}

diff --git a/src/qemu/qemu_hotplug.h b/src/qemu/qemu_hotplug.h
index 83bcaf980fd2966c9669400bd482898039ee490a..9f383f460267cbfc85c0891540eb9787ec55b882 100644 (file)
--- a/src/qemu/qemu_hotplug.h
+++ b/src/qemu/qemu_hotplug.h
@@ -165,3 +165,8 @@ int qemuHotplugAttachDBusVMState(virQEMUDriver *driver,
 int qemuHotplugRemoveDBusVMState(virQEMUDriver *driver,
                                  virDomainObj *vm,
                                  qemuDomainAsyncJob asyncJob);
+
+int qemuDomainChangeMemoryRequestedSize(virQEMUDriver *driver,
+                                        virDomainObj *vm,
+                                        const char *alias,
+                                        unsigned long long requestedsize);

diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c
index 42846349c427222147a226305a61fd03aec4a92e..24119ef66e332c3507d242bea82a340219108c6b 100644 (file)
--- a/src/qemu/qemu_monitor.c
+++ b/src/qemu/qemu_monitor.c
@@ -4625,3 +4625,16 @@ qemuMonitorSetAction(qemuMonitor *mon,
 
     return qemuMonitorJSONSetAction(mon, shutdown, reboot, watchdog, panic);
 }
+
+
+int
+qemuMonitorChangeMemoryRequestedSize(qemuMonitor *mon,
+                                     const char *alias,
+                                     unsigned long long requestedsize)
+{
+    VIR_DEBUG("alias=%s requestedsize=%llu", alias, requestedsize);
+
+    QEMU_CHECK_MONITOR(mon);
+
+    return qemuMonitorJSONChangeMemoryRequestedSize(mon, alias, requestedsize);
+}

diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h
index 2f08357c0c19b3d82ed177aaa2bf19f437c5e6da..0ebe73ac0445e940f6c5a9d8a81234fd2223f2d8 100644 (file)
--- a/src/qemu/qemu_monitor.h
+++ b/src/qemu/qemu_monitor.h
@@ -1537,3 +1537,8 @@ qemuMonitorSetAction(qemuMonitor *mon,
                      qemuMonitorActionReboot reboot,
                      qemuMonitorActionWatchdog watchdog,
                      qemuMonitorActionPanic panic);
+
+int
+qemuMonitorChangeMemoryRequestedSize(qemuMonitor *mon,
+                                     const char *alias,
+                                     unsigned long long requestedsize);

diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index 37e9c05d276c5adbf06e36a4a129b6620b05b683..4ef8abb5376f6d5518d80711cf38be1411c640fe 100644 (file)
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -9398,3 +9398,18 @@ qemuMonitorJSONSetAction(qemuMonitor *mon,
 
     return 0;
 }
+
+
+int
+qemuMonitorJSONChangeMemoryRequestedSize(qemuMonitor *mon,
+                                         const char *alias,
+                                         unsigned long long requestedsize)
+{
+    g_autofree char *path = g_strdup_printf("/machine/peripheral/%s", alias);
+    qemuMonitorJSONObjectProperty prop = {
+        .type = QEMU_MONITOR_OBJECT_PROPERTY_ULONG,
+        .val.ul = requestedsize * 1024, /* monitor needs bytes */
+    };
+
+    return qemuMonitorJSONSetObjectProperty(mon, path, "requested-size", &prop);
+}

diff --git a/src/qemu/qemu_monitor_json.h b/src/qemu/qemu_monitor_json.h
index c8cf734a1cc522d45b2b982f7bc2a03d703050a6..0289f8c3bf5a65c35b9e9a50c2d9eacb7de27b03 100644 (file)
--- a/src/qemu/qemu_monitor_json.h
+++ b/src/qemu/qemu_monitor_json.h
@@ -710,3 +710,8 @@ qemuMonitorJSONSetAction(qemuMonitor *mon,
                          qemuMonitorActionReboot reboot,
                          qemuMonitorActionWatchdog watchdog,
                          qemuMonitorActionPanic panic);
+
+int
+qemuMonitorJSONChangeMemoryRequestedSize(qemuMonitor *mon,
+                                         const char *alias,
+                                         unsigned long long requestedsize);