hmp/qmp: add block_set_io_throttle

Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block.c

@@ -1978,6 +1978,21 @@ BlockInfoList *qmp_query_block(Error **errp)
                 info->value->inserted->has_backing_file = true;
                 info->value->inserted->backing_file = g_strdup(bs->backing_file);
             }
+
+            if (bs->io_limits_enabled) {
+                info->value->inserted->bps =
+                               bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL];
+                info->value->inserted->bps_rd =
+                               bs->io_limits.bps[BLOCK_IO_LIMIT_READ];
+                info->value->inserted->bps_wr =
+                               bs->io_limits.bps[BLOCK_IO_LIMIT_WRITE];
+                info->value->inserted->iops =
+                               bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL];
+                info->value->inserted->iops_rd =
+                               bs->io_limits.iops[BLOCK_IO_LIMIT_READ];
+                info->value->inserted->iops_wr =
+                               bs->io_limits.iops[BLOCK_IO_LIMIT_WRITE];
+            }
         }
 
         /* XXX: waiting for the qapi to support GSList */

blockdev.c

@@ -759,6 +759,65 @@ int do_change_block(Monitor *mon, const char *device,
     return monitor_read_bdrv_key_start(mon, bs, NULL, NULL);
 }
 
+/* throttling disk I/O limits */
+int do_block_set_io_throttle(Monitor *mon,
+                       const QDict *qdict, QObject **ret_data)
+{
+    BlockIOLimit io_limits;
+    const char *devname = qdict_get_str(qdict, "device");
+    BlockDriverState *bs;
+
+    io_limits.bps[BLOCK_IO_LIMIT_TOTAL]
+                        = qdict_get_try_int(qdict, "bps", -1);
+    io_limits.bps[BLOCK_IO_LIMIT_READ]
+                        = qdict_get_try_int(qdict, "bps_rd", -1);
+    io_limits.bps[BLOCK_IO_LIMIT_WRITE]
+                        = qdict_get_try_int(qdict, "bps_wr", -1);
+    io_limits.iops[BLOCK_IO_LIMIT_TOTAL]
+                        = qdict_get_try_int(qdict, "iops", -1);
+    io_limits.iops[BLOCK_IO_LIMIT_READ]
+                        = qdict_get_try_int(qdict, "iops_rd", -1);
+    io_limits.iops[BLOCK_IO_LIMIT_WRITE]
+                        = qdict_get_try_int(qdict, "iops_wr", -1);
+
+    bs = bdrv_find(devname);
+    if (!bs) {
+        qerror_report(QERR_DEVICE_NOT_FOUND, devname);
+        return -1;
+    }
+
+    if ((io_limits.bps[BLOCK_IO_LIMIT_TOTAL] == -1)
+        || (io_limits.bps[BLOCK_IO_LIMIT_READ] == -1)
+        || (io_limits.bps[BLOCK_IO_LIMIT_WRITE] == -1)
+        || (io_limits.iops[BLOCK_IO_LIMIT_TOTAL] == -1)
+        || (io_limits.iops[BLOCK_IO_LIMIT_READ] == -1)
+        || (io_limits.iops[BLOCK_IO_LIMIT_WRITE] == -1)) {
+        qerror_report(QERR_MISSING_PARAMETER,
+                      "bps/bps_rd/bps_wr/iops/iops_rd/iops_wr");
+        return -1;
+    }
+
+    if (!do_check_io_limits(&io_limits)) {
+        qerror_report(QERR_INVALID_PARAMETER_COMBINATION);
+        return -1;
+    }
+
+    bs->io_limits = io_limits;
+    bs->slice_time = BLOCK_IO_SLICE_TIME;
+
+    if (!bs->io_limits_enabled && bdrv_io_limits_enabled(bs)) {
+        bdrv_io_limits_enable(bs);
+    } else if (bs->io_limits_enabled && !bdrv_io_limits_enabled(bs)) {
+        bdrv_io_limits_disable(bs);
+    } else {
+        if (bs->block_timer) {
+            qemu_mod_timer(bs->block_timer, qemu_get_clock_ns(vm_clock));
+        }
+    }
+
+    return 0;
+}
+
 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
 {
     const char *id = qdict_get_str(qdict, "id");

blockdev.h

@@ -63,6 +63,8 @@ int do_block_set_passwd(Monitor *mon, const QDict *qdict, QObject **ret_data);
 int do_change_block(Monitor *mon, const char *device,
                     const char *filename, const char *fmt);
 int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data);
+int do_block_set_io_throttle(Monitor *mon,
+                             const QDict *qdict, QObject **ret_data);
 int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data);
 int do_block_resize(Monitor *mon, const QDict *qdict, QObject **ret_data);
 

hmp-commands.hx

@@ -1206,6 +1206,21 @@ ETEXI
         .mhandler.cmd_new = do_block_set_passwd,
     },
 
+STEXI
+@item block_set_io_throttle @var{device} @var{bps} @var{bps_rd} @var{bps_wr} @var{iops} @var{iops_rd} @var{iops_wr}
+@findex block_set_io_throttle
+Change I/O throttle limits for a block drive to @var{bps} @var{bps_rd} @var{bps_wr} @var{iops} @var{iops_rd} @var{iops_wr}
+ETEXI
+
+    {
+        .name       = "block_set_io_throttle",
+        .args_type  = "device:B,bps:l,bps_rd:l,bps_wr:l,iops:l,iops_rd:l,iops_wr:l",
+        .params     = "device bps bps_rd bps_wr iops iops_rd iops_wr",
+        .help       = "change I/O throttle limits for a block drive",
+        .user_print = monitor_user_noop,
+        .mhandler.cmd_new = do_block_set_io_throttle,
+    },
+
 STEXI
 @item block_passwd @var{device} @var{password}
 @findex block_passwd

hmp.c

@@ -216,6 +216,16 @@ void hmp_info_block(Monitor *mon)
                            info->value->inserted->ro,
                            info->value->inserted->drv,
                            info->value->inserted->encrypted);
+
+            monitor_printf(mon, " bps=%" PRId64 " bps_rd=%" PRId64
+                            " bps_wr=%" PRId64 " iops=%" PRId64
+                            " iops_rd=%" PRId64 " iops_wr=%" PRId64,
+                            info->value->inserted->bps,
+                            info->value->inserted->bps_rd,
+                            info->value->inserted->bps_wr,
+                            info->value->inserted->iops,
+                            info->value->inserted->iops_rd,
+                            info->value->inserted->iops_wr);
         } else {
             monitor_printf(mon, " [not inserted]");
         }

qapi-schema.json

@@ -370,13 +370,27 @@
 #
 # @encrypted: true if the backing device is encrypted
 #
+# @bps: total throughput limit in bytes per second is specified
+#
+# @bps_rd: read throughput limit in bytes per second is specified
+#
+# @bps_wr: write throughput limit in bytes per second is specified
+#
+# @iops: total I/O operations per second is specified
+#
+# @iops_rd: read I/O operations per second is specified
+#
+# @iops_wr: write I/O operations per second is specified
+#
 # Since: 0.14.0
 #
 # Notes: This interface is only found in @BlockInfo.
 ##
 { 'type': 'BlockDeviceInfo',
   'data': { 'file': 'str', 'ro': 'bool', 'drv': 'str',
-            '*backing_file': 'str', 'encrypted': 'bool' } }
+            '*backing_file': 'str', 'encrypted': 'bool',
+            'bps': 'int', 'bps_rd': 'int', 'bps_wr': 'int',
+            'iops': 'int', 'iops_rd': 'int', 'iops_wr': 'int'} }
 
 ##
 # @BlockDeviceIoStatus:

qerror.c

@@ -246,6 +246,10 @@ static const QErrorStringTable qerror_table[] = {
         .error_fmt = QERR_QGA_COMMAND_FAILED,
         .desc      = "Guest agent command failed, error was '%(message)'",
     },
+    {
+        .error_fmt = QERR_INVALID_PARAMETER_COMBINATION,
+        .desc      = "Invalid paramter combination",
+    },
     {}
 };
 

qerror.h

@@ -204,4 +204,7 @@ QError *qobject_to_qerror(const QObject *obj);
 #define QERR_QGA_COMMAND_FAILED \
     "{ 'class': 'QgaCommandFailed', 'data': { 'message': %s } }"
 
+#define QERR_INVALID_PARAMETER_COMBINATION \
+    "{ 'class': 'InvalidParameterCombination', 'data': {} }"
+
 #endif /* QERROR_H */

qmp-commands.hx

@@ -848,6 +848,44 @@ Example:
                                                "password": "12345" } }
 <- { "return": {} }
 
+EQMP
+
+    {
+        .name       = "block_set_io_throttle",
+        .args_type  = "device:B,bps:l,bps_rd:l,bps_wr:l,iops:l,iops_rd:l,iops_wr:l",
+        .params     = "device bps bps_rd bps_wr iops iops_rd iops_wr",
+        .help       = "change I/O throttle limits for a block drive",
+        .user_print = monitor_user_noop,
+        .mhandler.cmd_new = do_block_set_io_throttle,
+    },
+
+SQMP
+block_set_io_throttle
+------------
+
+Change I/O throttle limits for a block drive.
+
+Arguments:
+
+- "device": device name (json-string)
+- "bps":  total throughput limit in bytes per second(json-int)
+- "bps_rd":  read throughput limit in bytes per second(json-int)
+- "bps_wr":  read throughput limit in bytes per second(json-int)
+- "iops":  total I/O operations per second(json-int)
+- "iops_rd":  read I/O operations per second(json-int)
+- "iops_wr":  write I/O operations per second(json-int)
+
+Example:
+
+-> { "execute": "block_set_io_throttle", "arguments": { "device": "virtio0",
+                                               "bps": "1000000",
+                                               "bps_rd": "0",
+                                               "bps_wr": "0",
+                                               "iops": "0",
+                                               "iops_rd": "0",
+                                               "iops_wr": "0" } }
+<- { "return": {} }
+
 EQMP
 
     {
@@ -1152,6 +1190,13 @@ Each json-object contain the following:
                                 "tftp", "vdi", "vmdk", "vpc", "vvfat"
          - "backing_file": backing file name (json-string, optional)
          - "encrypted": true if encrypted, false otherwise (json-bool)
+         - "bps": limit total bytes per second (json-int)
+         - "bps_rd": limit read bytes per second (json-int)
+         - "bps_wr": limit write bytes per second (json-int)
+         - "iops": limit total I/O operations per second (json-int)
+         - "iops_rd": limit read operations per second (json-int)
+         - "iops_wr": limit write operations per second (json-int)
+
 - "io-status": I/O operation status, only present if the device supports it
                and the VM is configured to stop on errors. It's always reset
                to "ok" when the "cont" command is issued (json_string, optional)
@@ -1171,7 +1216,13 @@ Example:
                "ro":false,
                "drv":"qcow2",
                "encrypted":false,
-               "file":"disks/test.img"
+               "file":"disks/test.img",
+               "bps":1000000,
+               "bps_rd":0,
+               "bps_wr":0,
+               "iops":1000000,
+               "iops_rd":0,
+               "iops_wr":0,
             },
             "type":"unknown"
          },