[Qemu-devel] [QEMU RFC PATCH v2 3/6] vmstate: Define VARRAY with VMS_ALLOC

[Jianjun Duan <duanj@linux.vnet.ibm.com>]

From: Alexey Kardashevskiy <aik@ozlabs.ru>

This allows dynamic allocation for migrating arrays.

Already existing VMSTATE_VARRAY_UINT32 requires an array to be
pre-allocated, however there are cases when the size is not known in
advance and there is no real need to enforce it.

This defines another variant of VMSTATE_VARRAY_UINT32 with WMS_ALLOC
flag which tells the receiving side to allocate memory for the array
before receiving the data.

The first user of it is a dynamic DMA window which existence and size
are totally dynamic.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
---
 include/migration/vmstate.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
index 84ee355..1622638 100644
--- a/include/migration/vmstate.h
+++ b/include/migration/vmstate.h
@@ -386,6 +386,16 @@ extern const VMStateInfo vmstate_info_bitmap;
     .offset     = vmstate_offset_pointer(_state, _field, _type),     \
 }
 
+#define VMSTATE_VARRAY_UINT32_ALLOC(_field, _state, _field_num, _version, _info, _type) {\
+    .name       = (stringify(_field)),                               \
+    .version_id = (_version),                                        \
+    .num_offset = vmstate_offset_value(_state, _field_num, uint32_t),\
+    .info       = &(_info),                                          \
+    .size       = sizeof(_type),                                     \
+    .flags      = VMS_VARRAY_UINT32|VMS_POINTER|VMS_ALLOC,           \
+    .offset     = vmstate_offset_pointer(_state, _field, _type),     \
+}
+
 #define VMSTATE_VARRAY_UINT16_UNSAFE(_field, _state, _field_num, _version, _info, _type) {\
     .name       = (stringify(_field)),                               \
     .version_id = (_version),                                        \
-- 
1.9.1