virgl: add VIRGL_RENDERER_NO_VIRGL

It disables vrend renderer.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Reviewed-by: Ryan Neph <ryanneph@google.com>
Reviewed-by: Gert Wollny <gert.wollny@collabora.com>

src/virgl_resource.c

@@ -59,7 +59,8 @@ virgl_resource_table_init(const struct virgl_resource_pipe_callbacks *callbacks)
    if (!virgl_resource_table)
       return ENOMEM;
 
-   pipe_callbacks = *callbacks;
+   if (callbacks)
+      pipe_callbacks = *callbacks;
 
    return 0;
 }

src/virglrenderer.c

@@ -71,6 +71,9 @@ static int virgl_renderer_resource_create_internal(struct virgl_renderer_resourc
    struct pipe_resource *pipe_res;
    struct vrend_renderer_resource_create_args vrend_args =  { 0 };
 
+   if (!state.vrend_initialized)
+      return EINVAL;
+
    /* do not accept handle 0 */
    if (args->handle == 0)
       return EINVAL;
@@ -160,7 +163,8 @@ void virgl_renderer_fill_caps(uint32_t set, uint32_t version,
    switch (set) {
    case VIRGL_RENDERER_CAPSET_VIRGL:
    case VIRGL_RENDERER_CAPSET_VIRGL2:
-      vrend_renderer_fill_caps(set, version, (union virgl_caps *)caps);
+      if (state.vrend_initialized)
+         vrend_renderer_fill_caps(set, version, (union virgl_caps *)caps);
       break;
    case VIRGL_RENDERER_CAPSET_VENUS:
       if (state.vkr_initialized)
@@ -209,6 +213,8 @@ int virgl_renderer_context_create_with_flags(uint32_t ctx_id,
    switch (capset_id) {
    case VIRGL_RENDERER_CAPSET_VIRGL:
    case VIRGL_RENDERER_CAPSET_VIRGL2:
+      if (!state.vrend_initialized)
+         return EINVAL;
       ctx = vrend_renderer_context_create(ctx_id, nlen, name);
       break;
    case VIRGL_RENDERER_CAPSET_VENUS:
@@ -416,7 +422,8 @@ int virgl_renderer_context_get_poll_fd(uint32_t ctx_id)
 void virgl_renderer_force_ctx_0(void)
 {
    TRACE_FUNC();
-   vrend_renderer_force_ctx_0();
+   if (state.vrend_initialized)
+      vrend_renderer_force_ctx_0();
 }
 
 void virgl_renderer_ctx_attach_resource(int ctx_id, int res_handle)
@@ -467,16 +474,16 @@ void virgl_renderer_get_cap_set(uint32_t cap_set, uint32_t *max_ver,
                                 uint32_t *max_size)
 {
    TRACE_FUNC();
+
+   /* this may be called before virgl_renderer_init */
    switch (cap_set) {
    case VIRGL_RENDERER_CAPSET_VIRGL:
    case VIRGL_RENDERER_CAPSET_VIRGL2:
       vrend_renderer_get_cap_set(cap_set, max_ver, max_size);
       break;
    case VIRGL_RENDERER_CAPSET_VENUS:
-      if (state.vkr_initialized) {
-         *max_ver = 0;
-         *max_size = vkr_get_capset(NULL);
-      }
+      *max_ver = 0;
+      *max_size = vkr_get_capset(NULL);
       break;
    default:
       *max_ver = 0;
@@ -604,9 +611,8 @@ int virgl_renderer_init(void *cookie, int flags, struct virgl_renderer_callbacks
       return -EBUSY;
 
    if (!state.client_initialized) {
-      if (!cookie || !cbs)
-         return -1;
-      if (cbs->version < 1 || cbs->version > VIRGL_RENDERER_CALLBACKS_VERSION)
+      if (cbs && (cbs->version < 1 ||
+                  cbs->version > VIRGL_RENDERER_CALLBACKS_VERSION))
          return -1;
 
       state.cookie = cookie;
@@ -616,7 +622,11 @@ int virgl_renderer_init(void *cookie, int flags, struct virgl_renderer_callbacks
    }
 
    if (!state.resource_initialized) {
-      ret = virgl_resource_table_init(vrend_renderer_get_pipe_callbacks());
+      const struct virgl_resource_pipe_callbacks *pipe_cbs =
+         (flags & VIRGL_RENDERER_NO_VIRGL) ? NULL :
+         vrend_renderer_get_pipe_callbacks();
+
+      ret = virgl_resource_table_init(pipe_cbs);
       if (ret)
          goto fail;
       state.resource_initialized = true;
@@ -629,8 +639,8 @@ int virgl_renderer_init(void *cookie, int flags, struct virgl_renderer_callbacks
       state.context_initialized = true;
    }
 
-   if (!state.winsys_initialized && (flags & (VIRGL_RENDERER_USE_EGL |
-                                              VIRGL_RENDERER_USE_GLX))) {
+   if (!state.winsys_initialized && !(flags & VIRGL_RENDERER_NO_VIRGL) &&
+       (flags & (VIRGL_RENDERER_USE_EGL | VIRGL_RENDERER_USE_GLX))) {
       int drm_fd = -1;
 
       if (flags & VIRGL_RENDERER_USE_EGL) {
@@ -647,9 +657,14 @@ int virgl_renderer_init(void *cookie, int flags, struct virgl_renderer_callbacks
       state.winsys_initialized = true;
    }
 
-   if (!state.vrend_initialized) {
+   if (!state.vrend_initialized && !(flags & VIRGL_RENDERER_NO_VIRGL)) {
       uint32_t renderer_flags = 0;
 
+      if (!cookie || !cbs) {
+         ret = -1;
+         goto fail;
+      }
+
       if (flags & VIRGL_RENDERER_THREAD_SYNC)
          renderer_flags |= VREND_USE_THREAD_SYNC;
       if (flags & VIRGL_RENDERER_USE_EXTERNAL_BLOB)

src/virglrenderer.h

@@ -94,6 +94,10 @@ struct virgl_renderer_callbacks {
  */
 #define VIRGL_RENDERER_VENUS         (1 << 6)
 
+/* Disable virgl renderer.
+ */
+#define VIRGL_RENDERER_NO_VIRGL      (1 << 7)
+
 #endif /* VIRGL_RENDERER_UNSTABLE_APIS */
 
 VIRGL_EXPORT int virgl_renderer_init(void *cookie, int flags, struct virgl_renderer_callbacks *cb);