@@ -1562,6 +1562,33 @@
'mode': 'Qcow2OverlapCheckMode' } }
##
+# @Qcow2OverlapStructures
+#
+# Contains options for controlling the behavior of the metadata overlap
+# prevention structures.
+#
+# These structures contain the position, length, and type of the metadata
+# structures; one contains all of them in compressed form, the other one takes
+# up more space, but has faster access times. Therefore, the latter acts as a
+# cache of the former.
+#
+# @cache-size: #optional size (in bytes) of the cache, defaults to 64 kB
+#
+# @total-size-limit: #optional maximum total size (in bytes) of all the metadata
+# overlap prevention data structures combined; if this limit
+# is exceeded, a QCOW2_OVERLAP_CHECK_MEMORY_LIMIT_REACHED
+# event will be emitted and some parts of the image may no
+# longer be protected against erroneous overwriting of
+# metadata by (meta)data of a different kind. Defaults to
+# SIZE_MAX.
+#
+# Since: 2.5
+##
+{ 'struct': 'Qcow2OverlapStructures',
+ 'data': { '*bitmap-size': 'int',
+ '*total-size-limit': 'int' } }
+
+##
# @BlockdevOptionsQcow2
#
# Driver specific block device options for qcow2.
@@ -1583,6 +1610,9 @@
# @overlap-check: #optional which overlap checks to perform for writes
# to the image, defaults to 'cached' (since 2.2)
#
+# @overlap-structures: #optional options for controlling the behavior of the
+# metadata overlap prevention structures (since 2.5)
+#
# @cache-size: #optional the maximum total size of the L2 table and
# refcount block caches in bytes (since 2.2)
#
@@ -1601,6 +1631,7 @@
'*pass-discard-snapshot': 'bool',
'*pass-discard-other': 'bool',
'*overlap-check': 'Qcow2OverlapChecks',
+ '*overlap-structures': 'Qcow2OverlapStructures',
'*cache-size': 'int',
'*l2-cache-size': 'int',
'*refcount-cache-size': 'int' } }
Expose the two new options for controlling the memory usage of the overlap check implementation via QAPI. Signed-off-by: Max Reitz <mreitz@redhat.com> --- qapi/block-core.json | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+)