[virglrenderer-devel] [PATCH] vrend: Nop sends to backing iovs for readonly textures.

[Jakob Bornecrantz]

As I have only done testing on the gles-backend with this patch
the code is only enabled on it. Further testing might show that
it is possible to run this code on all backends.

Fixes:
dEQP-GLES2.functional.texture.mipmap.2d.generate.a8_fastest
dEQP-GLES2.functional.texture.mipmap.2d.generate.a8_nicest
dEQP-GLES2.functional.texture.mipmap.2d.generate.l8_fastest
dEQP-GLES2.functional.texture.mipmap.2d.generate.l8_nicest
dEQP-GLES2.functional.texture.mipmap.2d.generate.la88_fastest
dEQP-GLES2.functional.texture.mipmap.2d.generate.la88_nicest
dEQP-GLES2.functional.texture.mipmap.cube.generate.a8_fastest
dEQP-GLES2.functional.texture.mipmap.cube.generate.a8_nicest
dEQP-GLES2.functional.texture.mipmap.cube.generate.l8_fastest
dEQP-GLES2.functional.texture.mipmap.cube.generate.l8_nicest
dEQP-GLES2.functional.texture.mipmap.cube.generate.la88_fastest
dEQP-GLES2.functional.texture.mipmap.cube.generate.la88_nicest

Signed-off-by: Jakob Bornecrantz <jakob at collabora.com>
---
 src/vrend_renderer.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/src/vrend_renderer.c b/src/vrend_renderer.c
index 0d0dbd9..e544386 100644
--- a/src/vrend_renderer.c
+++ b/src/vrend_renderer.c
@@ -5385,6 +5385,39 @@ static int vrend_transfer_send_readpixels(struct vrend_context *ctx,
    return 0;
 }
 
+static int vrend_transfer_send_readonly(struct vrend_context *ctx,
+                                        struct vrend_resource *res,
+                                        struct iovec *iov, int num_iovs,
+                                        const struct vrend_transfer_info *info)
+{
+   bool same_iov = true;
+   int i;
+
+   if (res->num_iovs == num_iovs) {
+      for (i = 0; i < res->num_iovs; i++) {
+         if (res->iov[i].iov_len != iov[i].iov_len ||
+             res->iov[i].iov_base != iov[i].iov_base) {
+            same_iov = false;
+         }
+      }
+   } else {
+      same_iov = false;
+   }
+
+   /*
+    * When we detect that we are reading back to the same iovs that are
+    * attached to the resource and we know that the resource can not
+    * be rendered to (as this function is only called then), we do not
+    * need to do anything more.
+    */
+   if (same_iov) {
+      return 0;
+   }
+
+   /* Fallback to getteximage, will probably fail on GLES. */
+   return vrend_transfer_send_getteximage(ctx, res, iov, num_iovs, info);
+}
+
 static int vrend_renderer_transfer_send_iov(struct vrend_context *ctx,
                                             struct vrend_resource *res,
                                             struct iovec *iov, int num_iovs,
@@ -5419,6 +5452,8 @@ static int vrend_renderer_transfer_send_iov(struct vrend_context *ctx,
       if (can_readpixels) {
          return vrend_transfer_send_readpixels(ctx, res,
                                                iov, num_iovs, info);
+      } else if (vrend_state.use_gles) {
+         return vrend_transfer_send_readonly(ctx, res, iov, num_iovs, info);
       }
 
       return vrend_transfer_send_getteximage(ctx, res,
-- 
2.14.1