qmp: add interface blockdev-snapshot-delete-internal-sync

This interface use id and name as optional parameters, to handle the
case that one image contain multiple snapshots with same name which
may be '', but with different id.

Adding parameter id is for historical compatiability reason, and
that case is not possible in qemu's new interface for internal
snapshot at block device level, but still possible in qemu-img.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/blockdev.c b/blockdev.c
index 0f4a7b5d85b029e0e9ad0e57822e92b8d60c2d7c..84d55c1adcb90df53f00d7a1525373f085b18bd5 100644 (file)
--- a/blockdev.c
+++ b/blockdev.c
@@ -871,6 +871,67 @@ void qmp_blockdev_snapshot_internal_sync(const char *device,
                        &snapshot, errp);
 }
 
+SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
+                                                         bool has_id,
+                                                         const char *id,
+                                                         bool has_name,
+                                                         const char *name,
+                                                         Error **errp)
+{
+    BlockDriverState *bs = bdrv_find(device);
+    QEMUSnapshotInfo sn;
+    Error *local_err = NULL;
+    SnapshotInfo *info = NULL;
+    int ret;
+
+    if (!bs) {
+        error_set(errp, QERR_DEVICE_NOT_FOUND, device);
+        return NULL;
+    }
+
+    if (!has_id) {
+        id = NULL;
+    }
+
+    if (!has_name) {
+        name = NULL;
+    }
+
+    if (!id && !name) {
+        error_setg(errp, "Name or id must be provided");
+        return NULL;
+    }
+
+    ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(errp, local_err);
+        return NULL;
+    }
+    if (!ret) {
+        error_setg(errp,
+                   "Snapshot with id '%s' and name '%s' does not exist on "
+                   "device '%s'",
+                   STR_OR_NULL(id), STR_OR_NULL(name), device);
+        return NULL;
+    }
+
+    bdrv_snapshot_delete(bs, id, name, &local_err);
+    if (error_is_set(&local_err)) {
+        error_propagate(errp, local_err);
+        return NULL;
+    }
+
+    info = g_malloc0(sizeof(SnapshotInfo));
+    info->id = g_strdup(sn.id_str);
+    info->name = g_strdup(sn.name);
+    info->date_nsec = sn.date_nsec;
+    info->date_sec = sn.date_sec;
+    info->vm_state_size = sn.vm_state_size;
+    info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000;
+    info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;
+
+    return info;
+}
 
 /* New and old BlockDriverState structs for group snapshots */
 

diff --git a/include/qemu-common.h b/include/qemu-common.h
index 6948bb91774a22d93dd59ecab62f061af803b093..50548361d09767155821af256a40c547a0cd31f7 100644 (file)
--- a/include/qemu-common.h
+++ b/include/qemu-common.h
@@ -191,6 +191,9 @@ int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix);
 int64_t strtosz_suffix_unit(const char *nptr, char **end,
                             const char default_suffix, int64_t unit);
 
+/* used to print char* safely */
+#define STR_OR_NULL(str) ((str) ? (str) : "null")
+
 /* path.c */
 void init_paths(const char *prefix);
 const char *path(const char *pathname);

diff --git a/qapi-schema.json b/qapi-schema.json
index 43faf9141055cd9235f6a4799701cebdf7d9e745..145eca8855cbbb798b164b2c6cae1471e24e194a 100644 (file)
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1824,6 +1824,33 @@
 { 'command': 'blockdev-snapshot-internal-sync',
   'data': 'BlockdevSnapshotInternal' }
 
+##
+# @blockdev-snapshot-delete-internal-sync
+#
+# Synchronously delete an internal snapshot of a block device, when the format
+# of the image used support it. The snapshot is identified by name or id or
+# both. One of the name or id is required. Return SnapshotInfo for the
+# successfully deleted snapshot.
+#
+# @device: the name of the device to delete the snapshot from
+#
+# @id: optional the snapshot's ID to be deleted
+#
+# @name: optional the snapshot's name to be deleted
+#
+# Returns: SnapshotInfo on success
+#          If @device is not a valid block device, DeviceNotFound
+#          If snapshot not found, GenericError
+#          If the format of the image used does not support it,
+#          BlockFormatFeatureNotSupported
+#          If @id and @name are both not specified, GenericError
+#
+# Since 1.7
+##
+{ 'command': 'blockdev-snapshot-delete-internal-sync',
+  'data': { 'device': 'str', '*id': 'str', '*name': 'str'},
+  'returns': 'SnapshotInfo' }
+
 ##
 # @human-monitor-command:
 #

diff --git a/qmp-commands.hx b/qmp-commands.hx
index 5c9ddef3a5f591c239c4b48bee8bf2decf5377ea..b17c46e0b1d108c816a2459999370ea65970e40c 100644 (file)
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1124,6 +1124,47 @@ Example:
    }
 <- { "return": {} }
 
+EQMP
+
+    {
+        .name       = "blockdev-snapshot-delete-internal-sync",
+        .args_type  = "device:B,id:s?,name:s?",
+        .mhandler.cmd_new =
+                      qmp_marshal_input_blockdev_snapshot_delete_internal_sync,
+    },
+
+SQMP
+blockdev-snapshot-delete-internal-sync
+--------------------------------------
+
+Synchronously delete an internal snapshot of a block device when the format of
+image used supports it.  The snapshot is identified by name or id or both.  One
+of name or id is required.  If the snapshot is not found, the operation will
+fail.
+
+Arguments:
+
+- "device": device name (json-string)
+- "id": ID of the snapshot (json-string, optional)
+- "name": name of the snapshot (json-string, optional)
+
+Example:
+
+-> { "execute": "blockdev-snapshot-delete-internal-sync",
+                "arguments": { "device": "ide-hd0",
+                               "name": "snapshot0" }
+   }
+<- { "return": {
+                   "id": "1",
+                   "name": "snapshot0",
+                   "vm-state-size": 0,
+                   "date-sec": 1000012,
+                   "date-nsec": 10,
+                   "vm-clock-sec": 100,
+                   "vm-clock-nsec": 20
+     }
+   }
+
 EQMP
 
     {