diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c
index 157a111..d0e6d8a 100644
--- a/hw/qdev-properties.c
+++ b/hw/qdev-properties.c
@@ -2,6 +2,7 @@
 #include "net.h"
 #include "qdev.h"
 #include "qerror.h"
+#include "parse_common.h"
 
 void *qdev_get_prop_ptr(DeviceState *dev, Property *prop)
 {
@@ -248,6 +249,39 @@ PropertyInfo qdev_prop_hex64 = {
     .print = print_hex64,
 };
 
+/* --- 64bit unsigned int 'size' type --- */
+
+static int parse_size(DeviceState *dev, Property *prop, const char *str)
+{
+    uint64_t *ptr = qdev_get_prop_ptr(dev, prop);
+
+    if(str != NULL)
+        return parse_common_size(str, ptr);
+
+    return -1;
+}
+
+static int print_size(DeviceState *dev, Property *prop, char *dest, size_t len)
+{
+    uint64_t *ptr = qdev_get_prop_ptr(dev, prop);
+    char suffixes[] = {'T', 'G', 'M', 'K', 'B'};
+    int i;
+    uint64_t div;
+
+    for(div = (long int)1 << 40 ;
+        !(*ptr / div) ; div >>= 10, i++);
+
+    return snprintf(dest, len, "%0.03f%c", (double)*ptr/div, suffixes[i]);
+}
+
+PropertyInfo qdev_prop_size = {
+    .name  = "size",
+    .type  = PROP_TYPE_SIZE,
+    .size  = sizeof(uint64_t),
+    .parse = parse_size,
+    .print = print_size,
+};
+
 /* --- string --- */
 
 static int parse_string(DeviceState *dev, Property *prop, const char *str)
diff --git a/hw/qdev.h b/hw/qdev.h
index 9475705..766e337 100644
--- a/hw/qdev.h
+++ b/hw/qdev.h
@@ -79,6 +79,7 @@ enum PropertyType {
     PROP_TYPE_UINT32,
     PROP_TYPE_INT32,
     PROP_TYPE_UINT64,
+    PROP_TYPE_SIZE,
     PROP_TYPE_TADDR,
     PROP_TYPE_MACADDR,
     PROP_TYPE_DRIVE,
@@ -188,6 +189,7 @@ extern PropertyInfo qdev_prop_int32;
 extern PropertyInfo qdev_prop_uint64;
 extern PropertyInfo qdev_prop_hex32;
 extern PropertyInfo qdev_prop_hex64;
+extern PropertyInfo qdev_prop_size;
 extern PropertyInfo qdev_prop_string;
 extern PropertyInfo qdev_prop_chr;
 extern PropertyInfo qdev_prop_ptr;
@@ -233,6 +235,8 @@ extern PropertyInfo qdev_prop_pci_devfn;
     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex32, uint32_t)
 #define DEFINE_PROP_HEX64(_n, _s, _f, _d)                       \
     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex64, uint64_t)
+#define DEFINE_PROP_SIZE(_n, _s, _f, _d)                       \
+    DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_size, uint64_t)
 #define DEFINE_PROP_PCI_DEVFN(_n, _s, _f, _d)                   \
     DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_pci_devfn, uint32_t)
 
diff --git a/parse_common.h b/parse_common.h
new file mode 100644
index 0000000..93b1fc2
--- /dev/null
+++ b/parse_common.h
@@ -0,0 +1,40 @@
+/*
+ * Common parsing routines
+ *
+ * Copyright Collabora 2009
+ *
+ * Author:
+ *  Ian Molton <ian.molton@collabora.co.uk>
+ *
+ * Derived from the parser in qemu-option.c
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+static inline int parse_common_size(const char *value, uint64_t *ptr) {
+    char *postfix;
+    double sizef;
+
+    sizef = strtod(value, &postfix);
+    switch (*postfix) {
+    case 'T':
+        sizef *= 1024;
+    case 'G':
+        sizef *= 1024;
+    case 'M':
+        sizef *= 1024;
+    case 'K':
+    case 'k':
+        sizef *= 1024;
+    case 'B':
+    case 'b':
+    case '\0':
+        *ptr = (uint64_t) sizef;
+        return 0;
+    }
+
+    return -1;
+}
+
diff --git a/qemu-option.c b/qemu-option.c
index f83d07c..0433f94 100644
--- a/qemu-option.c
+++ b/qemu-option.c
@@ -30,6 +30,7 @@
 #include "qemu-error.h"
 #include "qemu-objects.h"
 #include "qemu-option.h"
+#include "parse_common.h"
 
 /*
  * Extracts the name of an option from the parameter string (p points at the
@@ -205,28 +206,10 @@ static int parse_option_number(const char *name, const char *value, uint64_t *re
 
 static int parse_option_size(const char *name, const char *value, uint64_t *ret)
 {
-    char *postfix;
-    double sizef;
-
     if (value != NULL) {
-        sizef = strtod(value, &postfix);
-        switch (*postfix) {
-        case 'T':
-            sizef *= 1024;
-        case 'G':
-            sizef *= 1024;
-        case 'M':
-            sizef *= 1024;
-        case 'K':
-        case 'k':
-            sizef *= 1024;
-        case 'b':
-        case '\0':
-            *ret = (uint64_t) sizef;
-            break;
-        default:
+	if(parse_common_size(value, ret) == -1) {
             fprintf(stderr, "Option '%s' needs size as parameter\n", name);
-            fprintf(stderr, "You may use k, M, G or T suffixes for "
+            fprintf(stderr, "You may use B, K, M, G or T suffixes for bytes "
                     "kilobytes, megabytes, gigabytes and terabytes.\n");
             return -1;
         }
