[Qemu-devel] [PATCH v8 04/15] blockdev: Add blockdev-open-tray

[Max Reitz <mreitz@redhat.com>]

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 blockdev.c           | 36 ++++++++++++++++++++++++++++++++++++
 qapi/block-core.json | 32 ++++++++++++++++++++++++++++++++
 qmp-commands.hx      | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 116 insertions(+)

diff --git a/blockdev.c b/blockdev.c
index 18712d2..1119368 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2077,6 +2077,42 @@ out:
     aio_context_release(aio_context);
 }
 
+void qmp_blockdev_open_tray(const char *device, bool has_force, bool force,
+                            Error **errp)
+{
+    BlockBackend *blk;
+    bool locked;
+
+    if (!has_force) {
+        force = false;
+    }
+
+    blk = blk_by_name(device);
+    if (!blk) {
+        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
+                  "Device '%s' not found", device);
+        return;
+    }
+
+    if (!blk_dev_has_removable_media(blk)) {
+        error_setg(errp, "Device '%s' is not removable", device);
+        return;
+    }
+
+    if (blk_dev_is_tray_open(blk)) {
+        return;
+    }
+
+    locked = blk_dev_is_medium_locked(blk);
+    if (locked) {
+        blk_dev_eject_request(blk, force);
+    }
+
+    if (!locked || force) {
+        blk_dev_change_media_cb(blk, false);
+    }
+}
+
 /* throttling disk I/O limits */
 void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd,
                                int64_t bps_wr,
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 425fdab..b65ab81 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1876,6 +1876,38 @@
 ##
 { 'command': 'blockdev-add', 'data': { 'options': 'BlockdevOptions' } }
 
+##
+# @blockdev-open-tray:
+#
+# Opens a block device's tray. If there is a block driver state tree inserted as
+# a medium, it will become inaccessible to the guest (but it will remain
+# associated to the block device, so closing the tray will make it accessible
+# again).
+#
+# If the tray was already open before, this will be a no-op.
+#
+# Once the tray opens, a DEVICE_TRAY_MOVED event is emitted. There are cases in
+# which no such event will be generated, these include:
+# - if the guest has locked the tray, @force is false and the guest does not
+#   respond to the eject request
+# - if the BlockBackend denoted by @device does not have a guest device attached
+#   to it
+# - if the guest device does not have an actual tray and is empty, for instance
+#   for floppy disk drives
+#
+# @device: block device name
+#
+# @force:  #optional if false (the default), an eject request will be sent to
+#          the guest if it has locked the tray (and the tray will not be opened
+#          immediately); if true, the tray will be opened regardless of whether
+#          it is locked
+#
+# Since: 2.5
+##
+{ 'command': 'blockdev-open-tray',
+  'data': { 'device': 'str',
+            '*force': 'bool' } }
+
 
 ##
 # @BlockErrorAction
diff --git a/qmp-commands.hx b/qmp-commands.hx
index d7cf0ff..0b796f9 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -3936,6 +3936,54 @@ Example (2):
 EQMP
 
     {
+        .name       = "blockdev-open-tray",
+        .args_type  = "device:s,force:b?",
+        .mhandler.cmd_new = qmp_marshal_blockdev_open_tray,
+    },
+
+SQMP
+blockdev-open-tray
+------------------
+
+Opens a block device's tray. If there is a block driver state tree inserted as a
+medium, it will become inaccessible to the guest (but it will remain associated
+to the block device, so closing the tray will make it accessible again).
+
+If the tray was already open before, this will be a no-op.
+
+Once the tray opens, a DEVICE_TRAY_MOVED event is emitted. There are cases in
+which no such event will be generated, these include:
+- if the guest has locked the tray, @force is false and the guest does not
+  respond to the eject request
+- if the BlockBackend denoted by @device does not have a guest device attached
+  to it
+- if the guest device does not have an actual tray and is empty, for instance
+  for floppy disk drives
+
+Arguments:
+
+- "device": block device name (json-string)
+- "force": if false (the default), an eject request will be sent to the guest if
+           it has locked the tray (and the tray will not be opened immediately);
+           if true, the tray will be opened regardless of whether it is locked
+           (json-bool, optional)
+
+Example:
+
+-> { "execute": "blockdev-open-tray",
+     "arguments": { "device": "ide1-cd0" } }
+
+<- { "timestamp": { "seconds": 1418751016,
+                    "microseconds": 716996 },
+     "event": "DEVICE_TRAY_MOVED",
+     "data": { "device": "ide1-cd0",
+               "tray-open": true } }
+
+<- { "return": {} }
+
+EQMP
+
+    {
         .name       = "query-named-block-nodes",
         .args_type  = "",
         .mhandler.cmd_new = qmp_marshal_query_named_block_nodes,
-- 
2.6.2