virgl: wait after a flush

We really need to wait under certain circumstances, or we can end
up writing to memory the same time the host is reading.

Partial revert of d6dc68 ("virgl: use uint16_t mask instead of separate booleans").

Test cases:
   - dEQP-GLES31.functional.texture.texture_buffer.render_modify.as_vertex_array.bufferdata
     on vtest protocol version 2
   - Flickering during Alien Isolation
Fixes: d6dc68 ("virgl: use uint16_t mask instead of separate booleans")

Signed-off-by: Gurchetan Singh <[email protected]>
Reviewed-By: Gert Wollny <[email protected]>
Reviewed-By: Piotr Rak <[email protected]>

1 files changed, 6 insertions, 3 deletions

diff --git a/src/gallium/drivers/virgl/virgl_texture.c b/src/gallium/drivers/virgl/virgl_texture.c
index f0a2465021c..deb637ee58e 100644
--- a/src/gallium/drivers/virgl/virgl_texture.c
+++ b/src/gallium/drivers/virgl/virgl_texture.c
@@ -126,6 +126,7 @@ static void *texture_transfer_map_plain(struct pipe_context *ctx,
    struct virgl_winsys *vws = virgl_screen(ctx->screen)->vws;
    struct virgl_resource *vtex = virgl_resource(resource);
    struct virgl_transfer *trans;
+   bool flush, readback;
 
    trans = virgl_resource_create_transfer(&vctx->transfer_pool, resource,
                                           &vtex->metadata, level, usage, box);
@@ -133,15 +134,17 @@ static void *texture_transfer_map_plain(struct pipe_context *ctx,
 
    assert(resource->nr_samples <= 1);
 
-   if (virgl_res_needs_flush(vctx, trans))
+   flush = virgl_res_needs_flush(vctx, trans);
+   if (flush)
       ctx->flush(ctx, NULL, 0);
 
-   if (virgl_res_needs_readback(vctx, vtex, usage, level)) {
+   readback = virgl_res_needs_readback(vctx, vtex, usage, level);
+   if (readback)
       vws->transfer_get(vws, vtex->hw_res, box, trans->base.stride,
                         trans->l_stride, trans->offset, level);
 
+   if (readback || flush)
       vws->resource_wait(vws, vtex->hw_res);
-   }
 
    void *ptr = vws->resource_map(vws, vtex->hw_res);
    if (!ptr) {