Merge remote-tracking branch 'kwolf/for-anthony' into staging

* kwolf/for-anthony:
  test-coroutine: add performance test for nesting
  coroutine: adding configure option for sigaltstack coroutine backend
  coroutine: adding configure choose mechanism for coroutine backend
  coroutine: adding sigaltstack method (.c source)
  qcow2: Reduce number of I/O requests
  qcow2: Add qcow2_alloc_clusters_at()
  qcow2: Factor out count_cow_clusters
  qmp: convert blockdev-snapshot-sync to a wrapper around transactions
  add mode field to blockdev-snapshot-sync transaction item
  rename blockdev-group-snapshot-sync
  qapi: complete implementation of unions
  use QSIMPLEQ_FOREACH_SAFE when freeing list elements
  Add 'make check-block'
  make check: Add qemu-iotests subset
  qemu-iotests: Mark some tests as quick
  qcow2: Add error messages in qcow2_truncate
  block: handle -EBUSY in bdrv_commit_all()
  qcow2: Add some tracing
  qed: do not evict in-use L2 table cache entries
  Group snapshot: Fix format name for backing file

1 files changed, 52 insertions, 22 deletions

diff --git a/qapi-schema.json b/qapi-schema.json
index dd9e0e5434..04fa84fbde 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1120,27 +1120,58 @@
 { 'command': 'block_resize', 'data': { 'device': 'str', 'size': 'int' }}
 
 ##
-# @SnapshotDev
+# @NewImageMode
+#
+# An enumeration that tells QEMU how to set the backing file path in
+# a new image file.
+#
+# @existing: QEMU should look for an existing image file.
+#
+# @absolute-paths: QEMU should create a new image with absolute paths
+# for the backing file.
+#
+# Since: 1.1
+##
+{ 'enum': 'NewImageMode'
+  'data': [ 'existing', 'absolute-paths' ] }
+
+##
+# @BlockdevSnapshot
 #
 # @device:  the name of the device to generate the snapshot from.
 #
 # @snapshot-file: the target of the new image. A new file will be created.
 #
 # @format: #optional the format of the snapshot image, default is 'qcow2'.
+#
+# @mode: #optional whether and how QEMU should create a new image, default is
+# 'absolute-paths'.
+##
+{ 'type': 'BlockdevSnapshot',
+  'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str',
+            '*mode': 'NewImageMode' } }
+
+##
+# @BlockdevAction
+#
+# A discriminated record of operations that can be performed with
+# @transaction.
 ##
-{ 'type': 'SnapshotDev',
-  'data': {'device': 'str', 'snapshot-file': 'str', '*format': 'str' } }
+{ 'union': 'BlockdevAction',
+  'data': {
+       'blockdev-snapshot-sync': 'BlockdevSnapshot',
+   } }
 
 ##
-# @blockdev-group-snapshot-sync
+# @transaction
 #
-# Generates a synchronous snapshot of a group of one or more block devices,
-# as atomically as possible.  If the snapshot of any device in the group
-# fails, then the entire group snapshot will be abandoned and the
-# appropriate error returned.
+# Atomically operate on a group of one or more block devices.  If
+# any operation fails, then the entire set of actions will be
+# abandoned and the appropriate error returned.  The only operation
+# supported is currently blockdev-snapshot-sync.
 #
 #  List of:
-#  @SnapshotDev: information needed for the device snapshot
+#  @BlockdevAction: information needed for the device snapshot
 #
 # Returns: nothing on success
 #          If @device is not a valid block device, DeviceNotFound
@@ -1149,13 +1180,14 @@
 #          If @snapshot-file can't be opened, OpenFileFailed
 #          If @format is invalid, InvalidBlockFormat
 #
-# Note: The group snapshot attempt returns failure on the first snapshot
-# device failure.  Therefore, there will be only one device or snapshot file
-# returned in an error condition, and subsequent devices will not have been
-# attempted.
+# Note: The transaction aborts on the first failure.  Therefore, there will
+# be only one device or snapshot file returned in an error condition, and
+# subsequent actions will not have been attempted.
+#
+# Since 1.1
 ##
-{ 'command': 'blockdev-group-snapshot-sync',
-  'data': { 'devlist': [ 'SnapshotDev' ] } }
+{ 'command': 'transaction',
+  'data': { 'actions': [ 'BlockdevAction' ] } }
 
 ##
 # @blockdev-snapshot-sync
@@ -1170,21 +1202,19 @@
 #
 # @format: #optional the format of the snapshot image, default is 'qcow2'.
 #
+# @mode: #optional whether and how QEMU should create a new image, default is
+# 'absolute-paths'.
+#
 # Returns: nothing on success
 #          If @device is not a valid block device, DeviceNotFound
 #          If @snapshot-file can't be opened, OpenFileFailed
 #          If @format is invalid, InvalidBlockFormat
 #
-# Notes: One of the last steps taken by this command is to close the current
-#        image being used by @device and open the @snapshot-file one. If that
-#        fails, the command will try to reopen the original image file. If
-#        that also fails OpenFileFailed will be returned and the guest may get
-#        unexpected errors.
-#
 # Since 0.14.0
 ##
 { 'command': 'blockdev-snapshot-sync',
-  'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str' } }
+  'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str',
+            '*mode': 'NewImageMode'} }
 
 ##
 # @human-monitor-command: