Re: [PATCH RFC 03/15] backends/cryptodev-vhost-user: add memory isolation bool

[Akihiko Odaki]

On 2026/07/24 7:30, Connor Kite wrote:
Add a memory_isolation property to CryptoDevBackendVhostUser and
add add it as an optional member of CryptodevVhostUserProperties
in qapi.
This is needed to be able to specify memory isolation for
cryptodev-vhost-user objects, and the bool will eventually be
passed to vhost_user_init() in a future patch.

Signed-off-by: Connor Kite <connork...@gmail.com>
---
  backends/cryptodev-vhost-user.c | 22 ++++++++++++++++++++++
  qapi/qom.json                   |  6 +++++-
  2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/backends/cryptodev-vhost-user.c b/backends/cryptodev-vhost-user.c
index cc478d9902..e0547c5d40 100644
--- a/backends/cryptodev-vhost-user.c
+++ b/backends/cryptodev-vhost-user.c
@@ -49,6 +49,7 @@ struct CryptoDevBackendVhostUser {
      CharFrontend chr;
      char *chr_name;
      bool opened;
+    bool memory_isolation;
      CryptoDevBackendVhost *vhost_crypto[MAX_CRYPTO_QUEUE_NUM];
  };
  
@@ -392,6 +393,23 @@ static void cryptodev_vhost_user_finalize(Object *obj)
      g_free(s->chr_name);
  }
  
+static void cryptodev_vhost_user_set_mem_isolation(Object *obj, bool value,
+                                                   Error **errp)
+{
+    CryptoDevBackendVhostUser *s =
+                      CRYPTODEV_BACKEND_VHOST_USER(obj);
+
+    s->memory_isolation = value;

This setter should forbid setting once initialization finishes as done 
in cryptodev_vhost_user_set_chardev() since the value is copied into 
VhostUserState during initialization and setting this afterwards is 
ineffective.

Regards,
Akihiko Odaki

+}
+
+static bool cryptodev_vhost_user_get_mem_isolation(Object *obj, Error **errp)
+{
+    CryptoDevBackendVhostUser *s =
+                      CRYPTODEV_BACKEND_VHOST_USER(obj);
+
+    return s->memory_isolation;
+}
+
  static void
  cryptodev_vhost_user_class_init(ObjectClass *oc, const void *data)
  {
@@ -407,6 +425,10 @@ cryptodev_vhost_user_class_init(ObjectClass *oc, const 
void *data)
                                    cryptodev_vhost_user_get_chardev,
                                    cryptodev_vhost_user_set_chardev);
  
+    object_class_property_add_bool(oc, "memory-isolation",
+                                   cryptodev_vhost_user_get_mem_isolation,
+                                   cryptodev_vhost_user_set_mem_isolation);
+
  }
  
  static const TypeInfo cryptodev_vhost_user_info = {
diff --git a/qapi/qom.json b/qapi/qom.json
index c55776af7d..d7ca1b4203 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -350,11 +350,15 @@
  # @chardev: the name of a Unix domain socket character device that
  #     connects to the vhost-user server
  #
+# @memory-isolation: disables access from cryptodev to guest memory.
+#     (default: false)
+#
  # Since: 2.12
  ##
  { 'struct': 'CryptodevVhostUserProperties',
    'base': 'CryptodevBackendProperties',
-  'data': { 'chardev': 'str' },
+  'data': { 'chardev': 'str',
+            '*memory-isolation': 'bool' },
    'if': 'CONFIG_VHOST_CRYPTO' }
  
  ##