@@ -2096,6 +2096,8 @@ void qmp_blockdev_insert_medium(const char *device, const char *node_name,
void qmp_blockdev_change_medium(const char *device, const char *filename,
bool has_format, const char *format,
+ bool has_read_only,
+ BlockdevChangeReadOnlyMode read_only,
Error **errp)
{
BlockBackend *blk;
@@ -2117,7 +2119,28 @@ void qmp_blockdev_change_medium(const char *device, const char *filename,
}
blk_rs = blk_get_root_state(blk);
- bdrv_flags = blk_rs->read_only ? 0 : BDRV_O_RDWR;
+
+ if (!has_read_only) {
+ read_only = BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN;
+ }
+
+ switch (read_only) {
+ case BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN:
+ bdrv_flags = blk_rs->read_only ? 0 : BDRV_O_RDWR;
+ break;
+
+ case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_ONLY:
+ bdrv_flags = 0;
+ break;
+
+ case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_WRITE:
+ bdrv_flags = BDRV_O_RDWR;
+ break;
+
+ default:
+ abort();
+ }
+
bdrv_flags |= blk_rs->open_flags & ~BDRV_O_RDWR;
if (has_format) {
@@ -1348,7 +1348,7 @@ void hmp_change(Monitor *mon, const QDict *qdict)
}
qmp_change("vnc", target, !!arg, arg, &err);
} else {
- qmp_blockdev_change_medium(device, target, !!arg, arg, &err);
+ qmp_blockdev_change_medium(device, target, !!arg, arg, false, 0, &err);
if (err &&
error_get_class(err) == ERROR_CLASS_DEVICE_ENCRYPTED) {
error_free(err);
@@ -1949,6 +1949,24 @@
##
+# @BlockdevChangeReadOnlyMode:
+#
+# Specifies the new read-only mode of a block device subject to the
+# @blockdev-change-medium command.
+#
+# @retain: Retains the current read-only mode
+#
+# @read-only: Makes the device read-only
+#
+# @read-write: Makes the device writable
+#
+# Since: 2.3
+##
+{ 'enum': 'BlockdevChangeReadOnlyMode',
+ 'data': ['retain', 'read-only', 'read-write'] }
+
+
+##
# @blockdev-change-medium:
#
# Changes the medium inserted into a block device by ejecting the current medium
@@ -1963,12 +1981,16 @@
# @format: #optional, format to open the new image with (defaults to
# the probed format)
#
+# @read-only-mode: #optional, change the read-only mode of the device; defaults
+# to 'retain'
+#
# Since: 2.5
##
{ 'command': 'blockdev-change-medium',
'data': { 'device': 'str',
'filename': 'str',
- '*format': 'str' } }
+ '*format': 'str',
+ '*read-only-mode': 'BlockdevChangeReadOnlyMode' } }
##
@@ -4155,7 +4155,7 @@ EQMP
{
.name = "blockdev-change-medium",
- .args_type = "device:B,filename:F,format:s?",
+ .args_type = "device:B,filename:F,format:s?,read-only-mode:s?",
.mhandler.cmd_new = qmp_marshal_blockdev_change_medium,
},
@@ -4171,6 +4171,8 @@ Arguments:
- "device": device name (json-string)
- "filename": filename of the new image (json-string)
- "format": format of the new image (json-string, optional)
+- "read-only-mode": new read-only mode (json-string, optional)
+ - Possible values: "retain" (default), "read-only", "read-write"
Examples:
@@ -4182,6 +4184,26 @@ Examples:
"format": "raw" } }
<- { "return": {} }
+2. Load a read-only medium into a writable drive
+
+-> { "execute": "blockdev-change-medium",
+ "arguments": { "device": "isa-fd0",
+ "filename": "/srv/images/ro.img",
+ "format": "raw",
+ "read-only-mode": "retain" } }
+
+<- { "error":
+ { "class": "GenericError",
+ "desc": "Could not open '/srv/images/ro.img': Permission denied" } }
+
+-> { "execute": "blockdev-change-medium",
+ "arguments": { "device": "isa-fd0",
+ "filename": "/srv/images/ro.img",
+ "format": "raw",
+ "read-only-mode": "read-only" } }
+
+<- { "return": {} }
+
EQMP
{
@@ -414,7 +414,8 @@ void qmp_change(const char *device, const char *target,
if (strcmp(device, "vnc") == 0) {
qmp_change_vnc(target, has_arg, arg, errp);
} else {
- qmp_blockdev_change_medium(device, target, has_arg, arg, errp);
+ qmp_blockdev_change_medium(device, target, has_arg, arg, false, 0,
+ errp);
}
}