diff --git a/include/qemu/option.h b/include/qemu/option.h
index c3b0a91..de4912a 100644
--- a/include/qemu/option.h
+++ b/include/qemu/option.h
@@ -111,6 +111,7 @@ struct QemuOptsList {
 };
 
 const char *qemu_opt_get(QemuOpts *opts, const char *name);
+char *qemu_opt_get_del(QemuOpts *opts, const char *name);
 /**
  * qemu_opt_has_help_opt:
  * @opts: options to search for a help request
@@ -126,6 +127,11 @@ bool qemu_opt_has_help_opt(QemuOpts *opts);
 bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval);
 uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval);
 uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval);
+bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval);
+uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
+                                 uint64_t defval);
+uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
+                               uint64_t defval);
 int qemu_opt_unset(QemuOpts *opts, const char *name);
 int qemu_opt_set(QemuOpts *opts, const char *name, const char *value);
 void qemu_opt_set_err(QemuOpts *opts, const char *name, const char *value,
@@ -161,4 +167,7 @@ void qemu_opts_print(QemuOpts *opts);
 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
                       int abort_on_failure);
 
+QemuOptsList *qemu_opts_append(QemuOptsList *dst, QemuOptsList *list);
+void qemu_opts_free(QemuOptsList *list);
+void qemu_opts_print_help(QemuOptsList *list);
 #endif
diff --git a/util/qemu-option.c b/util/qemu-option.c
index df79235..2c450e0 100644
--- a/util/qemu-option.c
+++ b/util/qemu-option.c
@@ -35,6 +35,7 @@
 
 static const QemuOptDesc *find_desc_by_name(const QemuOptDesc *desc,
                                             const char *name);
+static void qemu_opt_del(QemuOpt *opt);
 
 /*
  * Extracts the name of an option from the parameter string (p points at the
@@ -379,6 +380,74 @@ QEMUOptionParameter *append_option_parameters(QEMUOptionParameter *dest,
     return dest;
 }
 
+static size_t count_opts_list(QemuOptsList *list)
+{
+    QemuOptDesc *desc = NULL;
+    size_t num_opts = 0;
+
+    if (!list) {
+        return 0;
+    }
+
+    desc = list->desc;
+    while (desc && desc->name) {
+        num_opts++;
+        desc++;
+    }
+
+    return num_opts;
+}
+
+/* Create a new QemuOptsList with a desc of the merge of the first
+ * and second. It will allocate space for one new QemuOptsList plus
+ * enough space for QemuOptDesc in first and second QemuOptsList.
+ * First argument's QemuOptDesc members take precedence over second's.
+ * The result's name and implied_opt_name are not copied from them.
+ * Both merge_lists should not be set. Both lists can be NULL.
+ */
+QemuOptsList *qemu_opts_append(QemuOptsList *dst,
+                               QemuOptsList *list)
+{
+    size_t num_opts, num_dst_opts;
+    QemuOptsList *tmp;
+    QemuOptDesc *desc;
+
+    if (!dst && !list) {
+        return NULL;
+    }
+
+    num_opts = count_opts_list(dst);
+    num_opts += count_opts_list(list);
+    tmp = g_malloc0(sizeof(QemuOptsList) +
+                    (num_opts + 1) * sizeof(QemuOptDesc));
+    QTAILQ_INIT(&tmp->head);
+    num_dst_opts = 0;
+
+    /* copy dst->desc to new list */
+    if (dst) {
+        desc = dst->desc;
+        while (desc && desc->name) {
+            tmp->desc[num_dst_opts++] = *desc;
+            tmp->desc[num_dst_opts].name = NULL;
+            desc++;
+        }
+    }
+
+    /* add list->desc to new list */
+    if (list) {
+        desc = list->desc;
+        while (desc && desc->name) {
+            if (find_desc_by_name(tmp->desc, desc->name) == NULL) {
+                tmp->desc[num_dst_opts++] = *desc;
+                tmp->desc[num_dst_opts].name = NULL;
+            }
+            desc++;
+        }
+    }
+
+    return tmp;
+}
+
 /*
  * Parses a parameter string (param) into an option list (dest).
  *
@@ -574,6 +643,29 @@ const char *qemu_opt_get(QemuOpts *opts, const char *name)
     return opt ? opt->str : NULL;
 }
 
+char *qemu_opt_get_del(QemuOpts *opts, const char *name)
+{
+    QemuOpt *opt;
+    const QemuOptDesc *desc;
+    char *str = NULL;
+
+    if (opts == NULL) {
+        return NULL;
+    }
+
+    opt = qemu_opt_find(opts, name);
+    if (!opt) {
+        desc = find_desc_by_name(opts->list->desc, name);
+        if (desc && desc->def_value_str) {
+            str = g_strdup(desc->def_value_str);
+        }
+        return str;
+    }
+    str = g_strdup(opt->str);
+    qemu_opt_del(opt);
+    return str;
+}
+
 bool qemu_opt_has_help_opt(QemuOpts *opts)
 {
     QemuOpt *opt;
@@ -586,9 +678,11 @@ bool qemu_opt_has_help_opt(QemuOpts *opts)
     return false;
 }
 
-bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
+static bool _qemu_opt_get_bool(QemuOpts *opts, const char *name,
+                               bool defval, bool del)
 {
     QemuOpt *opt;
+    bool ret = defval;
 
     if (opts == NULL) {
         return defval;
@@ -599,19 +693,35 @@ bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
     if (opt == NULL) {
         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
         if (desc && desc->def_value_str) {
-            parse_option_bool(name, desc->def_value_str, &defval, &error_abort);
+            parse_option_bool(name, desc->def_value_str, &ret, &error_abort);
         }
-        return defval;
+        return ret;
     }
     if (opt->desc) {
         assert(opt->desc->type == QEMU_OPT_BOOL);
     }
-    return opt->value.boolean;
+    ret = opt->value.boolean;
+    if (del) {
+        qemu_opt_del(opt);
+    }
+    return ret;
 }
 
-uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
+bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
+{
+    return _qemu_opt_get_bool(opts, name, defval, false);
+}
+
+bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval)
+{
+    return _qemu_opt_get_bool(opts, name, defval, true);
+}
+
+static uint64_t _qemu_opt_get_number(QemuOpts *opts, const char *name,
+                                     uint64_t defval, bool del)
 {
     QemuOpt *opt;
+    uint64_t ret = defval;
 
     if (opts == NULL) {
         return defval;
@@ -622,20 +732,36 @@ uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
     if (opt == NULL) {
         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
         if (desc && desc->def_value_str) {
-            parse_option_number(name, desc->def_value_str, &defval,
-                                &error_abort);
+            parse_option_number(name, desc->def_value_str, &ret, &error_abort);
         }
-        return defval;
+        return ret;
     }
     if (opt->desc) {
         assert(opt->desc->type == QEMU_OPT_NUMBER);
     }
-    return opt->value.uint;
+    ret = opt->value.uint;
+    if (del) {
+        qemu_opt_del(opt);
+    }
+    return ret;
 }
 
-uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
+uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
+{
+    return _qemu_opt_get_number(opts, name, defval, false);
+}
+
+uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
+                                 uint64_t defval)
+{
+    return _qemu_opt_get_number(opts, name, defval, true);
+}
+
+static uint64_t _qemu_opt_get_size(QemuOpts *opts, const char *name,
+                                   uint64_t defval, bool del)
 {
     QemuOpt *opt;
+    uint64_t ret = defval;
 
     if (opts == NULL) {
         return defval;
@@ -645,14 +771,29 @@ uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
     if (opt == NULL) {
         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
         if (desc && desc->def_value_str) {
-            parse_option_size(name, desc->def_value_str, &defval, &error_abort);
+            parse_option_size(name, desc->def_value_str, &ret, &error_abort);
         }
-        return defval;
+        return ret;
     }
     if (opt->desc) {
         assert(opt->desc->type == QEMU_OPT_SIZE);
     }
-    return opt->value.uint;
+    ret = opt->value.uint;
+    if (del) {
+        qemu_opt_del(opt);
+    }
+    return ret;
+}
+
+uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
+{
+    return _qemu_opt_get_size(opts, name, defval, false);
+}
+
+uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
+                               uint64_t defval)
+{
+    return _qemu_opt_get_size(opts, name, defval, true);
 }
 
 static void qemu_opt_parse(QemuOpt *opt, Error **errp)
@@ -1302,3 +1443,24 @@ int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
     loc_pop(&loc);
     return rc;
 }
+
+/* free a QemuOptsList, can accept NULL as arguments */
+void qemu_opts_free(QemuOptsList *list)
+{
+    if (!list) {
+        return;
+    }
+
+    g_free(list);
+}
+
+void qemu_opts_print_help(QemuOptsList *list)
+{
+    int i;
+    printf("Supported options:\n");
+    for (i = 0; list && list->desc[i].name; i++) {
+        printf("%-16s %s\n", list->desc[i].name,
+               list->desc[i].help ?
+               list->desc[i].help : "");
+    }
+}
