qapi: Restrict balloon-related commands to machine code

Only qemu-system-FOO and qemu-storage-daemon provide QMP
monitors, therefore such declarations and definitions are
irrelevant for user-mode emulation.

Restricting the balloon-related commands to machine.json pulls less
QAPI-generated code into user-mode.

Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200913195348.1064154-4-philmd@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

hw/virtio/virtio-balloon.c

@@ -24,7 +24,7 @@
 #include "hw/virtio/virtio-balloon.h"
 #include "exec/address-spaces.h"
 #include "qapi/error.h"
-#include "qapi/qapi-events-misc.h"
+#include "qapi/qapi-events-machine.h"
 #include "qapi/visitor.h"
 #include "trace.h"
 #include "qemu/error-report.h"

include/sysemu/balloon.h

@@ -15,7 +15,7 @@
 #define QEMU_BALLOON_H
 
 #include "exec/cpu-common.h"
-#include "qapi/qapi-types-misc.h"
+#include "qapi/qapi-types-machine.h"
 
 typedef void (QEMUBalloonEvent)(void *opaque, ram_addr_t target);
 typedef void (QEMUBalloonStatus)(void *opaque, BalloonInfo *info);

monitor/hmp-cmds.c

@@ -32,6 +32,7 @@
 #include "qapi/qapi-commands-block.h"
 #include "qapi/qapi-commands-char.h"
 #include "qapi/qapi-commands-control.h"
+#include "qapi/qapi-commands-machine.h"
 #include "qapi/qapi-commands-migration.h"
 #include "qapi/qapi-commands-misc.h"
 #include "qapi/qapi-commands-net.h"

qapi/machine.json

@@ -945,3 +945,93 @@
   'data': 'NumaOptions',
   'allow-preconfig': true
 }
+
+##
+# @balloon:
+#
+# Request the balloon driver to change its balloon size.
+#
+# @value: the target logical size of the VM in bytes
+#         We can deduce the size of the balloon using this formula:
+#            logical_vm_size = vm_ram_size - balloon_size
+#         From it we have: balloon_size = vm_ram_size - @value
+#
+# Returns: - Nothing on success
+#          - If the balloon driver is enabled but not functional because the KVM
+#            kernel module cannot support it, KvmMissingCap
+#          - If no balloon device is present, DeviceNotActive
+#
+# Notes: This command just issues a request to the guest.  When it returns,
+#        the balloon size may not have changed.  A guest can change the balloon
+#        size independent of this command.
+#
+# Since: 0.14.0
+#
+# Example:
+#
+# -> { "execute": "balloon", "arguments": { "value": 536870912 } }
+# <- { "return": {} }
+#
+# With a 2.5GiB guest this command inflated the ballon to 3GiB.
+#
+##
+{ 'command': 'balloon', 'data': {'value': 'int'} }
+
+##
+# @BalloonInfo:
+#
+# Information about the guest balloon device.
+#
+# @actual: the logical size of the VM in bytes
+#          Formula used: logical_vm_size = vm_ram_size - balloon_size
+#
+# Since: 0.14.0
+#
+##
+{ 'struct': 'BalloonInfo', 'data': {'actual': 'int' } }
+
+##
+# @query-balloon:
+#
+# Return information about the balloon device.
+#
+# Returns: - @BalloonInfo on success
+#          - If the balloon driver is enabled but not functional because the KVM
+#            kernel module cannot support it, KvmMissingCap
+#          - If no balloon device is present, DeviceNotActive
+#
+# Since: 0.14.0
+#
+# Example:
+#
+# -> { "execute": "query-balloon" }
+# <- { "return": {
+#          "actual": 1073741824,
+#       }
+#    }
+#
+##
+{ 'command': 'query-balloon', 'returns': 'BalloonInfo' }
+
+##
+# @BALLOON_CHANGE:
+#
+# Emitted when the guest changes the actual BALLOON level. This value is
+# equivalent to the @actual field return by the 'query-balloon' command
+#
+# @actual: the logical size of the VM in bytes
+#          Formula used: logical_vm_size = vm_ram_size - balloon_size
+#
+# Note: this event is rate-limited.
+#
+# Since: 1.2
+#
+# Example:
+#
+# <- { "event": "BALLOON_CHANGE",
+#      "data": { "actual": 944766976 },
+#      "timestamp": { "seconds": 1267020223, "microseconds": 435656 } }
+#
+##
+{ 'event': 'BALLOON_CHANGE',
+  'data': { 'actual': 'int' } }

qapi/misc.json

@@ -187,65 +187,6 @@
 { 'command': 'query-iothreads', 'returns': ['IOThreadInfo'],
   'allow-preconfig': true }
 
-##
-# @BalloonInfo:
-#
-# Information about the guest balloon device.
-#
-# @actual: the logical size of the VM in bytes
-#          Formula used: logical_vm_size = vm_ram_size - balloon_size
-#
-# Since: 0.14.0
-#
-##
-{ 'struct': 'BalloonInfo', 'data': {'actual': 'int' } }
-
-##
-# @query-balloon:
-#
-# Return information about the balloon device.
-#
-# Returns: - @BalloonInfo on success
-#          - If the balloon driver is enabled but not functional because the KVM
-#            kernel module cannot support it, KvmMissingCap
-#          - If no balloon device is present, DeviceNotActive
-#
-# Since: 0.14.0
-#
-# Example:
-#
-# -> { "execute": "query-balloon" }
-# <- { "return": {
-#          "actual": 1073741824,
-#       }
-#    }
-#
-##
-{ 'command': 'query-balloon', 'returns': 'BalloonInfo' }
-
-##
-# @BALLOON_CHANGE:
-#
-# Emitted when the guest changes the actual BALLOON level. This value is
-# equivalent to the @actual field return by the 'query-balloon' command
-#
-# @actual: the logical size of the VM in bytes
-#          Formula used: logical_vm_size = vm_ram_size - balloon_size
-#
-# Note: this event is rate-limited.
-#
-# Since: 1.2
-#
-# Example:
-#
-# <- { "event": "BALLOON_CHANGE",
-#      "data": { "actual": 944766976 },
-#      "timestamp": { "seconds": 1267020223, "microseconds": 435656 } }
-#
-##
-{ 'event': 'BALLOON_CHANGE',
-  'data': { 'actual': 'int' } }
-
 ##
 # @PciMemoryRange:
 #
@@ -756,37 +697,6 @@
 ##
 { 'command': 'inject-nmi' }
 
-##
-# @balloon:
-#
-# Request the balloon driver to change its balloon size.
-#
-# @value: the target logical size of the VM in bytes
-#         We can deduce the size of the balloon using this formula:
-#            logical_vm_size = vm_ram_size - balloon_size
-#         From it we have: balloon_size = vm_ram_size - @value
-#
-# Returns: - Nothing on success
-#          - If the balloon driver is enabled but not functional because the KVM
-#            kernel module cannot support it, KvmMissingCap
-#          - If no balloon device is present, DeviceNotActive
-#
-# Notes: This command just issues a request to the guest.  When it returns,
-#        the balloon size may not have changed.  A guest can change the balloon
-#        size independent of this command.
-#
-# Since: 0.14.0
-#
-# Example:
-#
-# -> { "execute": "balloon", "arguments": { "value": 536870912 } }
-# <- { "return": {} }
-#
-# With a 2.5GiB guest this command inflated the balloon to 3GiB.
-#
-##
-{ 'command': 'balloon', 'data': {'value': 'int'} }
-
 ##
 # @human-monitor-command:
 #

softmmu/balloon.c

@@ -29,7 +29,7 @@
 #include "sysemu/kvm.h"
 #include "sysemu/balloon.h"
 #include "qapi/error.h"
-#include "qapi/qapi-commands-misc.h"
+#include "qapi/qapi-commands-machine.h"
 #include "qapi/qmp/qerror.h"
 #include "trace.h"