Implement virDomain{Set, Get}BlockIoTune for the qemu driver

Implement the block I/O throttle setting and getting support to qemu
driver.
Signed-off-by: NLei Li <lilei@linux.vnet.ibm.com>
Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

src/qemu/qemu_command.c

@@ -1866,6 +1866,37 @@ qemuBuildDriveStr(virConnectPtr conn ATTRIBUTE_UNUSED,
         }
     }
 
+    /* block I/O throttling */
+    if (disk->blkdeviotune.total_bytes_sec) {
+        virBufferAsprintf(&opt, ",bps=%llu",
+                          disk->blkdeviotune.total_bytes_sec);
+    }
+
+    if (disk->blkdeviotune.read_bytes_sec) {
+        virBufferAsprintf(&opt, ",bps_rd=%llu",
+                          disk->blkdeviotune.read_bytes_sec);
+    }
+
+    if (disk->blkdeviotune.write_bytes_sec) {
+        virBufferAsprintf(&opt, ",bps_wr=%llu",
+                          disk->blkdeviotune.write_bytes_sec);
+    }
+
+    if (disk->blkdeviotune.total_iops_sec) {
+        virBufferAsprintf(&opt, ",iops=%llu",
+                          disk->blkdeviotune.total_iops_sec);
+    }
+
+    if (disk->blkdeviotune.read_iops_sec) {
+        virBufferAsprintf(&opt, ",iops_rd=%llu",
+                          disk->blkdeviotune.read_iops_sec);
+    }
+
+    if (disk->blkdeviotune.write_iops_sec) {
+        virBufferAsprintf(&opt, ",iops_wr=%llu",
+                          disk->blkdeviotune.write_iops_sec);
+    }
+
     if (virBufferError(&opt)) {
         virReportOOMError();
         goto error;

src/qemu/qemu_driver.c

@@ -95,6 +95,8 @@
 
 #define QEMU_NB_MEM_PARAM  3
 
+#define QEMU_NB_BLOCK_IO_TUNE_PARAM  6
+
 #if HAVE_LINUX_KVM_H
 # include <linux/kvm.h>
 #endif
@@ -11062,6 +11064,336 @@ cleanup:
     return ret;
 }
 
+static int
+qemuDomainSetBlockIoTune(virDomainPtr dom,
+                         const char *disk,
+                         virTypedParameterPtr params,
+                         int nparams,
+                         unsigned int flags)
+{
+    struct qemud_driver *driver = dom->conn->privateData;
+    virDomainObjPtr vm = NULL;
+    qemuDomainObjPrivatePtr priv;
+    virDomainDefPtr persistentDef = NULL;
+    virDomainBlockIoTuneInfo info;
+    char uuidstr[VIR_UUID_STRING_BUFLEN];
+    const char *device = NULL;
+    int ret = -1;
+    int i;
+    bool isActive;
+    int idx = -1;
+
+    virCheckFlags(VIR_DOMAIN_AFFECT_LIVE |
+                  VIR_DOMAIN_AFFECT_CONFIG, -1);
+
+    memset(&info, 0, sizeof(info));
+
+    qemuDriverLock(driver);
+    virUUIDFormat(dom->uuid, uuidstr);
+    vm = virDomainFindByUUID(&driver->domains, dom->uuid);
+    if (!vm) {
+        qemuReportError(VIR_ERR_NO_DOMAIN,
+                        _("no domain with matching uuid '%s'"), uuidstr);
+        goto cleanup;
+    }
+
+    device = qemuDiskPathToAlias(vm, disk);
+    if (!device) {
+        goto cleanup;
+    }
+
+    if (qemuDomainObjBeginJobWithDriver(driver, vm, QEMU_JOB_MODIFY) < 0)
+        goto cleanup;
+
+    isActive = virDomainObjIsActive(vm);
+
+    if (flags == VIR_DOMAIN_AFFECT_CURRENT) {
+        if (isActive)
+            flags = VIR_DOMAIN_AFFECT_LIVE;
+        else
+            flags = VIR_DOMAIN_AFFECT_CONFIG;
+    }
+
+    if (!isActive && (flags & VIR_DOMAIN_AFFECT_LIVE)) {
+        qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                        _("domain is not running"));
+        goto endjob;
+    }
+
+    if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
+        if (!vm->persistent) {
+            qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                            _("cannot change persistent config of a transient domain"));
+            goto endjob;
+        }
+        if (!(persistentDef = virDomainObjGetPersistentDef(driver->caps, vm)))
+            goto endjob;
+        idx = virDomainDiskIndexByName(persistentDef, disk, true);
+        if (idx < 0)
+            goto endjob;
+    }
+
+    for (i = 0; i < nparams; i++) {
+        virTypedParameterPtr param = &params[i];
+
+        if (param->type != VIR_TYPED_PARAM_ULLONG) {
+            qemuReportError(VIR_ERR_INVALID_ARG,
+                            _("expected unsigned long long for parameter %s"),
+                            param->field);
+            goto endjob;
+        }
+
+        if (STREQ(param->field, VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_BYTES_SEC)) {
+            info.total_bytes_sec = param->value.ul;
+        } else if (STREQ(param->field,
+                         VIR_DOMAIN_BLOCK_IOTUNE_READ_BYTES_SEC)) {
+            info.read_bytes_sec = param->value.ul;
+        } else if (STREQ(param->field,
+                         VIR_DOMAIN_BLOCK_IOTUNE_WRITE_BYTES_SEC)) {
+            info.write_bytes_sec = param->value.ul;
+        } else if (STREQ(param->field,
+                         VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_IOPS_SEC)) {
+            info.total_iops_sec = param->value.ul;
+        } else if (STREQ(param->field,
+                         VIR_DOMAIN_BLOCK_IOTUNE_READ_IOPS_SEC)) {
+            info.read_iops_sec = param->value.ul;
+        } else if (STREQ(param->field,
+                         VIR_DOMAIN_BLOCK_IOTUNE_WRITE_IOPS_SEC)) {
+            info.write_iops_sec = param->value.ul;
+        } else {
+            qemuReportError(VIR_ERR_INVALID_ARG,
+                            _("Unrecognized parameter %s"),
+                            param->field);
+            goto endjob;
+        }
+    }
+
+    if ((info.total_bytes_sec && info.read_bytes_sec) ||
+        (info.total_bytes_sec && info.write_bytes_sec)) {
+        qemuReportError(VIR_ERR_INVALID_ARG, "%s",
+                        _("total and read/write of bytes_sec cannot be set at the same time"));
+        goto endjob;
+    }
+
+    if ((info.total_iops_sec && info.read_iops_sec) ||
+        (info.total_iops_sec && info.write_iops_sec)) {
+        qemuReportError(VIR_ERR_INVALID_ARG, "%s",
+                        _("total and read/write of iops_sec cannot be set at the same time"));
+        goto endjob;
+    }
+
+    if (flags & VIR_DOMAIN_AFFECT_LIVE) {
+        priv = vm->privateData;
+        qemuDomainObjEnterMonitorWithDriver(driver, vm);
+        ret = qemuMonitorSetBlockIoThrottle(priv->mon, device, &info);
+        qemuDomainObjExitMonitorWithDriver(driver, vm);
+    }
+    if (ret < 0)
+        goto endjob;
+
+    if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
+        sa_assert(persistentDef && idx >= 0);
+        persistentDef->disks[idx]->blkdeviotune = info;
+        ret = virDomainSaveConfig(driver->configDir, persistentDef);
+        if (ret < 0) {
+            qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                           _("Write to config file failed"));
+            goto endjob;
+        }
+    }
+
+endjob:
+    if (qemuDomainObjEndJob(driver, vm) == 0)
+        vm = NULL;
+
+cleanup:
+    VIR_FREE(device);
+    if (vm)
+        virDomainObjUnlock(vm);
+    qemuDriverUnlock(driver);
+    return ret;
+}
+
+static int
+qemuDomainGetBlockIoTune(virDomainPtr dom,
+                         const char *disk,
+                         virTypedParameterPtr params,
+                         int *nparams,
+                         unsigned int flags)
+{
+    struct qemud_driver *driver = dom->conn->privateData;
+    virDomainObjPtr vm = NULL;
+    qemuDomainObjPrivatePtr priv;
+    virDomainDefPtr persistentDef = NULL;
+    virDomainBlockIoTuneInfo reply;
+    char uuidstr[VIR_UUID_STRING_BUFLEN];
+    const char *device = NULL;
+    int ret = -1;
+    int i;
+    bool isActive;
+
+    virCheckFlags(VIR_DOMAIN_AFFECT_LIVE |
+                  VIR_DOMAIN_AFFECT_CONFIG |
+                  VIR_TYPED_PARAM_STRING_OKAY, -1);
+
+    /* We don't return strings, and thus trivially support this flag.  */
+    flags &= ~VIR_TYPED_PARAM_STRING_OKAY;
+
+    qemuDriverLock(driver);
+    virUUIDFormat(dom->uuid, uuidstr);
+    vm = virDomainFindByUUID(&driver->domains, dom->uuid);
+    if (!vm) {
+        qemuReportError(VIR_ERR_NO_DOMAIN,
+                        _("no domain with matching uuid '%s'"), uuidstr);
+        goto cleanup;
+    }
+
+    if ((*nparams) == 0) {
+        /* Current number of parameters supported by QEMU Block I/O Throttling */
+        *nparams = QEMU_NB_BLOCK_IO_TUNE_PARAM;
+        ret = 0;
+        goto cleanup;
+    }
+
+    device = qemuDiskPathToAlias(vm, disk);
+
+    if (!device) {
+        goto cleanup;
+    }
+
+    if (qemuDomainObjBeginJobWithDriver(driver, vm, QEMU_JOB_MODIFY) < 0)
+        goto cleanup;
+
+    isActive = virDomainObjIsActive(vm);
+
+    if (flags  == VIR_DOMAIN_AFFECT_CURRENT) {
+        if (isActive)
+            flags = VIR_DOMAIN_AFFECT_LIVE;
+        else
+            flags = VIR_DOMAIN_AFFECT_CONFIG;
+    }
+
+    if (!isActive && (flags & VIR_DOMAIN_AFFECT_LIVE)) {
+        qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                        _("domain is not running"));
+        goto endjob;
+    }
+
+    if (flags & VIR_DOMAIN_AFFECT_LIVE) {
+        priv = vm->privateData;
+        qemuDomainObjEnterMonitorWithDriver(driver, vm);
+        ret = qemuMonitorGetBlockIoThrottle(priv->mon, device, &reply);
+        qemuDomainObjExitMonitorWithDriver(driver, vm);
+        if (ret < 0)
+            goto endjob;
+    }
+
+    if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
+        if (!vm->persistent) {
+            qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                            _("domain is transient"));
+            goto endjob;
+        }
+        if (!(persistentDef = virDomainObjGetPersistentDef(driver->caps, vm)))
+            goto endjob;
+
+        int idx = virDomainDiskIndexByName(vm->def, disk, true);
+        if (idx < 0)
+            goto endjob;
+        reply = persistentDef->disks[idx]->blkdeviotune;
+    }
+
+    for (i = 0; i < QEMU_NB_BLOCK_IO_TUNE_PARAM && i < *nparams; i++) {
+        virTypedParameterPtr param = &params[i];
+        param->value.ul = 0;
+        param->type = VIR_TYPED_PARAM_ULLONG;
+
+        switch(i) {
+        case 0:
+            if (virStrcpyStatic(param->field,
+                                VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_BYTES_SEC) == NULL) {
+                qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                                _("Field name '%s' too long"),
+                                VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_BYTES_SEC);
+                goto endjob;
+            }
+            param->value.ul = reply.total_bytes_sec;
+            break;
+
+        case 1:
+            if (virStrcpyStatic(param->field,
+                                VIR_DOMAIN_BLOCK_IOTUNE_READ_BYTES_SEC) == NULL) {
+                qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                                _("Field name '%s' too long"),
+                                VIR_DOMAIN_BLOCK_IOTUNE_READ_BYTES_SEC);
+                goto endjob;
+            }
+            param->value.ul = reply.read_bytes_sec;
+            break;
+
+        case 2:
+            if (virStrcpyStatic(param->field,
+                                VIR_DOMAIN_BLOCK_IOTUNE_WRITE_BYTES_SEC) == NULL) {
+                qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                                _("Field name '%s' too long"),
+                                VIR_DOMAIN_BLOCK_IOTUNE_WRITE_BYTES_SEC);
+                goto endjob;
+            }
+            param->value.ul = reply.write_bytes_sec;
+            break;
+
+        case 3:
+            if (virStrcpyStatic(param->field,
+                                VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_IOPS_SEC) == NULL) {
+                qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                                _("Field name '%s' too long"),
+                                VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_IOPS_SEC);
+                goto endjob;
+            }
+            param->value.ul = reply.total_iops_sec;
+            break;
+
+        case 4:
+            if (virStrcpyStatic(param->field,
+                                VIR_DOMAIN_BLOCK_IOTUNE_READ_IOPS_SEC) == NULL) {
+                qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                                _("Field name '%s' too long"),
+                                VIR_DOMAIN_BLOCK_IOTUNE_READ_IOPS_SEC);
+                goto endjob;
+            }
+            param->value.ul = reply.read_iops_sec;
+            break;
+
+        case 5:
+            if (virStrcpyStatic(param->field,
+                                VIR_DOMAIN_BLOCK_IOTUNE_WRITE_IOPS_SEC) == NULL) {
+                qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                                _("Field name '%s' too long"),
+                                VIR_DOMAIN_BLOCK_IOTUNE_WRITE_IOPS_SEC);
+                goto endjob;
+            }
+            param->value.ul = reply.write_iops_sec;
+            break;
+        default:
+            break;
+        }
+    }
+
+    if (*nparams > QEMU_NB_BLOCK_IO_TUNE_PARAM)
+        *nparams = QEMU_NB_BLOCK_IO_TUNE_PARAM;
+    ret = 0;
+
+endjob:
+    if (qemuDomainObjEndJob(driver, vm) == 0)
+        vm = NULL;
+
+cleanup:
+    VIR_FREE(device);
+    if (vm)
+        virDomainObjUnlock(vm);
+    qemuDriverUnlock(driver);
+    return ret;
+}
 
 static virDriver qemuDriver = {
     .no = VIR_DRV_QEMU,
@@ -11209,6 +11541,8 @@ static virDriver qemuDriver = {
     .domainBlockPull = qemuDomainBlockPull, /* 0.9.4 */
     .isAlive = qemuIsAlive, /* 0.9.8 */
     .nodeSuspendForDuration = nodeSuspendForDuration, /* 0.9.8 */
+    .domainSetBlockIoTune = qemuDomainSetBlockIoTune, /* 0.9.8 */
+    .domainGetBlockIoTune = qemuDomainGetBlockIoTune, /* 0.9.8 */
 };
 
 

src/qemu/qemu_monitor.c

@@ -2582,6 +2582,39 @@ int qemuMonitorBlockJob(qemuMonitorPtr mon,
     return ret;
 }
 
+int qemuMonitorSetBlockIoThrottle(qemuMonitorPtr mon,
+                                  const char *device,
+                                  virDomainBlockIoTuneInfoPtr info)
+{
+    int ret;
+
+    VIR_DEBUG("mon=%p, device=%p, info=%p", mon, device, info);
+
+    if (mon->json) {
+        ret = qemuMonitorJSONSetBlockIoThrottle(mon, device, info);
+    } else {
+        ret = qemuMonitorTextSetBlockIoThrottle(mon, device, info);
+    }
+    return ret;
+}
+
+int qemuMonitorGetBlockIoThrottle(qemuMonitorPtr mon,
+                                  const char *device,
+                                  virDomainBlockIoTuneInfoPtr reply)
+{
+    int ret;
+
+    VIR_DEBUG("mon=%p, device=%p, reply=%p", mon, device, reply);
+
+    if (mon->json) {
+        ret = qemuMonitorJSONGetBlockIoThrottle(mon, device, reply);
+    } else {
+        ret = qemuMonitorTextGetBlockIoThrottle(mon, device, reply);
+    }
+    return ret;
+}
+
+
 int qemuMonitorVMStatusToPausedReason(const char *status)
 {
     int st;

src/qemu/qemu_monitor.h

@@ -522,6 +522,14 @@ int qemuMonitorOpenGraphics(qemuMonitorPtr mon,
                             const char *fdname,
                             bool skipauth);
 
+int qemuMonitorSetBlockIoThrottle(qemuMonitorPtr mon,
+                                  const char *device,
+                                  virDomainBlockIoTuneInfoPtr info);
+
+int qemuMonitorGetBlockIoThrottle(qemuMonitorPtr mon,
+                                  const char *device,
+                                  virDomainBlockIoTuneInfoPtr reply);
+
 /**
  * When running two dd process and using <> redirection, we need a
  * shell that will not truncate files.  These two strings serve that

src/qemu/qemu_monitor_json.c

@@ -3308,3 +3308,179 @@ int qemuMonitorJSONOpenGraphics(qemuMonitorPtr mon,
     virJSONValueFree(reply);
     return ret;
 }
+
+
+static int
+qemuMonitorJSONBlockIoThrottleInfo(virJSONValuePtr result,
+                                   const char *device,
+                                   virDomainBlockIoTuneInfoPtr reply)
+{
+    virJSONValuePtr io_throttle;
+    int ret = -1;
+    int i;
+    int found = 0;
+
+    io_throttle = virJSONValueObjectGet(result, "return");
+
+    if (!io_throttle || io_throttle->type != VIR_JSON_TYPE_ARRAY) {
+        qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                        _(" block_io_throttle reply was missing device list"));
+        goto cleanup;
+    }
+
+    for (i = 0; i < virJSONValueArraySize(io_throttle); i++) {
+        virJSONValuePtr temp_dev = virJSONValueArrayGet(io_throttle, i);
+        virJSONValuePtr inserted;
+        const char *current_dev;
+
+        if (!temp_dev || temp_dev->type != VIR_JSON_TYPE_OBJECT) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("block io throttle device entry was not in expected format"));
+            goto cleanup;
+        }
+
+        if ((current_dev = virJSONValueObjectGetString(temp_dev, "device")) == NULL) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("block io throttle device entry was not in expected format"));
+            goto cleanup;
+        }
+
+       if(STRPREFIX(current_dev, QEMU_DRIVE_HOST_PREFIX))
+            current_dev += strlen(QEMU_DRIVE_HOST_PREFIX);
+
+        if (STREQ(current_dev, device))
+            continue;
+
+        found = 1;
+        if ((inserted = virJSONValueObjectGet(temp_dev, "inserted")) == NULL ||
+            inserted->type != VIR_JSON_TYPE_OBJECT) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("block io throttle inserted entry was not in expected format"));
+            goto cleanup;
+        }
+
+        if (virJSONValueObjectGetNumberUlong(inserted, "bps", &reply->total_bytes_sec) < 0) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("cannot read total_bytes_sec"));
+            goto cleanup;
+        }
+
+        if (virJSONValueObjectGetNumberUlong(inserted, "bps_rd", &reply->read_bytes_sec) < 0) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("cannot read read_bytes_sec"));
+            goto cleanup;
+        }
+
+        if (virJSONValueObjectGetNumberUlong(inserted, "bps_wr", &reply->write_bytes_sec) < 0) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("cannot read write_bytes_sec"));
+            goto cleanup;
+        }
+
+        if (virJSONValueObjectGetNumberUlong(inserted, "iops", &reply->total_iops_sec) < 0) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("cannot read total_iops_sec"));
+            goto cleanup;
+        }
+
+        if (virJSONValueObjectGetNumberUlong(inserted, "iops_rd", &reply->read_iops_sec) < 0) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("cannot read read_iops_sec"));
+            goto cleanup;
+        }
+
+        if (virJSONValueObjectGetNumberUlong(inserted, "iops_wr", &reply->write_iops_sec) < 0) {
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                            _("cannot read write_iops_sec"));
+            goto cleanup;
+        }
+        break;
+    }
+
+    if (!found) {
+        qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                        _("cannot find throttling info for device '%s'"),
+                        device);
+        goto cleanup;
+    }
+    ret = 0;
+
+cleanup:
+    return ret;
+}
+
+int qemuMonitorJSONSetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr info)
+{
+    int ret = -1;
+    virJSONValuePtr cmd = NULL;
+    virJSONValuePtr result = NULL;
+
+    cmd = qemuMonitorJSONMakeCommand("block_set_io_throttle",
+                                     "s:device", device,
+                                     "U:bps", info->total_bytes_sec,
+                                     "U:bps_rd", info->read_bytes_sec,
+                                     "U:bps_wr", info->write_bytes_sec,
+                                     "U:iops", info->total_iops_sec,
+                                     "U:iops_rd", info->read_iops_sec,
+                                     "U:iops_wr", info->write_iops_sec,
+                                     NULL);
+    if (!cmd)
+        return -1;
+
+    ret = qemuMonitorJSONCommand(mon, cmd, &result);
+
+    if (ret == 0 && virJSONValueObjectHasKey(result, "error")) {
+        if (qemuMonitorJSONHasError(result, "DeviceNotActive"))
+            qemuReportError(VIR_ERR_OPERATION_INVALID,
+                _("No active operation on device: %s"), device);
+        else if (qemuMonitorJSONHasError(result, "NotSupported"))
+            qemuReportError(VIR_ERR_OPERATION_INVALID,
+                _("Operation is not supported for device: %s"), device);
+        else
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                _("Unexpected error"));
+        ret = -1;
+    }
+
+    virJSONValueFree(cmd);
+    virJSONValueFree(result);
+    return ret;
+}
+
+int qemuMonitorJSONGetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr reply)
+{
+    int ret = -1;
+    virJSONValuePtr cmd = NULL;
+    virJSONValuePtr result = NULL;
+
+    cmd = qemuMonitorJSONMakeCommand("query-block", NULL);
+    if (!cmd) {
+        return -1;
+    }
+
+    ret = qemuMonitorJSONCommand(mon, cmd, &result);
+
+    if (ret == 0 && virJSONValueObjectHasKey(result, "error")) {
+        if (qemuMonitorJSONHasError(result, "DeviceNotActive"))
+            qemuReportError(VIR_ERR_OPERATION_INVALID,
+                _("No active operation on device: %s"), device);
+        else if (qemuMonitorJSONHasError(result, "NotSupported"))
+            qemuReportError(VIR_ERR_OPERATION_INVALID,
+                _("Operation is not supported for device: %s"), device);
+        else
+            qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                _("Unexpected error"));
+        ret = -1;
+    }
+
+    if (ret == 0)
+        ret = qemuMonitorJSONBlockIoThrottleInfo(result, device, reply);
+
+    virJSONValueFree(cmd);
+    virJSONValueFree(result);
+    return ret;
+}

src/qemu/qemu_monitor_json.h

@@ -257,4 +257,12 @@ int qemuMonitorJSONOpenGraphics(qemuMonitorPtr mon,
                                 const char *fdname,
                                 bool skipauth);
 
+int qemuMonitorJSONSetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr info);
+
+int qemuMonitorJSONGetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr reply);
+
 #endif /* QEMU_MONITOR_JSON_H */

src/qemu/qemu_monitor_text.c

@@ -812,7 +812,7 @@ int qemuMonitorTextGetBlockInfo(qemuMonitorPtr mon,
             if (!eol)
                 eol = p + strlen(p);
 
-            p += devnamelen + 2; /*Skip to first label. */
+            p += devnamelen + 2; /* Skip to first label. */
 
             while (*p) {
                 if (STRPREFIX(p, "removable=")) {
@@ -3462,3 +3462,152 @@ cleanup:
     VIR_FREE(cmd);
     return ret;
 }
+
+
+int qemuMonitorTextSetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr info)
+{
+    char *cmd = NULL;
+    char *result = NULL;
+    int ret = 0;
+    const char *cmd_name = NULL;
+
+    /* For the not specified fields, 0 by default */
+    cmd_name = "block_set_io_throttle";
+    ret = virAsprintf(&cmd, "%s %s %llu %llu %llu %llu %llu %llu", cmd_name,
+                      device, info->total_bytes_sec, info->read_bytes_sec,
+                      info->write_bytes_sec, info->total_iops_sec,
+                      info->read_iops_sec, info->write_iops_sec);
+
+    if (ret < 0) {
+        virReportOOMError();
+        return -1;
+    }
+
+    if (qemuMonitorHMPCommand(mon, cmd, &result) < 0) {
+        qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                        "%s", _("cannot run monitor command"));
+        ret = -1;
+        goto cleanup;
+    }
+
+    if (qemuMonitorTextCommandNotFound(cmd_name, result)) {
+        qemuReportError(VIR_ERR_OPERATION_INVALID,
+                        _("Command '%s' is not found"), cmd_name);
+        ret = -1;
+        goto cleanup;
+    }
+
+cleanup:
+    VIR_FREE(cmd);
+    VIR_FREE(result);
+    return ret;
+}
+
+static int
+qemuMonitorTextParseBlockIoThrottle(const char *result,
+                                    const char *device,
+                                    virDomainBlockIoTuneInfoPtr reply)
+{
+    char *dummy = NULL;
+    int ret = -1;
+    const char *p, *eol;
+    int devnamelen = strlen(device);
+
+    p = result;
+
+    while (*p) {
+        if (STRPREFIX(p, QEMU_DRIVE_HOST_PREFIX))
+            p += strlen(QEMU_DRIVE_HOST_PREFIX);
+
+        if (STREQLEN(p, device, devnamelen) &&
+            p[devnamelen] == ':' && p[devnamelen+1] == ' ') {
+
+            eol = strchr(p, '\n');
+            if (!eol)
+                eol = p + strlen(p);
+
+            p += devnamelen + 2; /* Skip to first label. */
+
+            while (*p) {
+                if (STRPREFIX(p, "bps=")) {
+                    p += strlen("bps=");
+                    if (virStrToLong_ull(p, &dummy, 10, &reply->total_bytes_sec) == -1)
+                        VIR_DEBUG("error reading total_bytes_sec: %s", p);
+                } else if (STRPREFIX(p, "bps_rd=")) {
+                    p += strlen("bps_rd=");
+                    if (virStrToLong_ull(p, &dummy, 10, &reply->read_bytes_sec)  == -1)
+                        VIR_DEBUG("error reading read_bytes_sec: %s", p);
+                } else if (STRPREFIX(p, "bps_wr=")) {
+                    p += strlen("bps_wr=");
+                    if (virStrToLong_ull(p, &dummy, 10, &reply->write_bytes_sec) == -1)
+                        VIR_DEBUG("error reading write_bytes_sec: %s", p);
+                } else if (STRPREFIX(p, "iops=")) {
+                    p += strlen("iops=");
+                    if (virStrToLong_ull(p, &dummy, 10, &reply->total_iops_sec) == -1)
+                        VIR_DEBUG("error reading total_iops_sec: %s", p);
+                } else if (STRPREFIX(p, "iops_rd=")) {
+                    p += strlen("iops_rd=");
+                    if (virStrToLong_ull(p, &dummy, 10, &reply->read_iops_sec) == -1)
+                        VIR_DEBUG("error reading read_iops_sec: %s", p);
+                } else if (STRPREFIX(p, "iops_wr=")) {
+                    p += strlen("iops_wr=");
+                    if (virStrToLong_ull(p, &dummy, 10, &reply->write_iops_sec) == -1)
+                        VIR_DEBUG("error reading write_iops_sec: %s", p);
+                } else {
+                    VIR_DEBUG(" unknown block info %s", p);
+                }
+
+                /* Skip to next label. */
+                p = strchr (p, ' ');
+                if (!p || p >= eol)
+                    break;
+                p++;
+            }
+            ret = 0;
+            goto cleanup;
+        }
+
+        /* Skip to next line. */
+        p = strchr (p, '\n');
+        if (!p)
+            break;
+        p++;
+    }
+
+    qemuReportError(VIR_ERR_INVALID_ARG,
+                    _("No info for device '%s'"), device);
+
+cleanup:
+    return ret;
+}
+
+int qemuMonitorTextGetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr reply)
+{
+    char *result = NULL;
+    int ret = 0;
+    const char *cmd_name = "info block";
+
+    if (qemuMonitorHMPCommand(mon, cmd_name, &result) < 0) {
+        qemuReportError(VIR_ERR_INTERNAL_ERROR,
+                        "%s", _("cannot run monitor command"));
+        ret = -1;
+        goto cleanup;
+    }
+
+    if (qemuMonitorTextCommandNotFound(cmd_name, result)) {
+        qemuReportError(VIR_ERR_OPERATION_INVALID,
+                        _("Command '%s' is not found"), cmd_name);
+        ret = -1;
+        goto cleanup;
+    }
+
+    ret = qemuMonitorTextParseBlockIoThrottle(result, device, reply);
+
+cleanup:
+    VIR_FREE(result);
+    return ret;
+}

src/qemu/qemu_monitor_text.h

@@ -250,4 +250,12 @@ int qemuMonitorTextOpenGraphics(qemuMonitorPtr mon,
                                 const char *fdname,
                                 bool skipauth);
 
+int qemuMonitorTextSetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr info);
+
+int qemuMonitorTextGetBlockIoThrottle(qemuMonitorPtr mon,
+                                      const char *device,
+                                      virDomainBlockIoTuneInfoPtr reply);
+
 #endif /* QEMU_MONITOR_TEXT_H */