vrend: specify if a transfer occurs in context zero or not

A transfer won't occur in context zero if the transfer command
comes from submit_cmd. We need to restore prior state.

With the recent framebuffer binding cleanups, we really only need
to worry about the framebuffer.

Reviewed-by: Gert Wollny <gert.wollny@collabora.com>

src/virglrenderer.c

@@ -131,6 +131,7 @@ int virgl_renderer_transfer_write_iov(uint32_t handle,
    transfer_info.offset = offset;
    transfer_info.iovec = iovec;
    transfer_info.iovec_cnt = iovec_cnt;
+   transfer_info.context0 = true;
 
    return vrend_renderer_transfer_iov(&transfer_info, VREND_TRANSFER_WRITE);
 }
@@ -153,6 +154,7 @@ int virgl_renderer_transfer_read_iov(uint32_t handle, uint32_t ctx_id,
    transfer_info.offset = offset;
    transfer_info.iovec = iovec;
    transfer_info.iovec_cnt = iovec_cnt;
+   transfer_info.context0 = true;
 
    return vrend_renderer_transfer_iov(&transfer_info, VREND_TRANSFER_READ);
 }

src/vrend_renderer.c

@@ -6654,6 +6654,10 @@ static int vrend_transfer_send_readpixels(struct vrend_context *ctx,
                           separate_invert);
       free(data);
    }
+
+   if (!info->context0 && ctx->sub)
+      glBindFramebuffer(GL_FRAMEBUFFER, ctx->sub->fb_id);
+
    return 0;
 }
 
@@ -6780,7 +6784,8 @@ int vrend_renderer_transfer_iov(const struct vrend_transfer_info *info,
    if (!check_iov_bounds(res, info, iov, num_iovs))
       return EINVAL;
 
-   vrend_hw_switch_context(vrend_lookup_renderer_ctx(0), true);
+   if (info->context0)
+      vrend_hw_switch_context(vrend_lookup_renderer_ctx(0), true);
 
    if (transfer_mode == VREND_TRANSFER_WRITE)
       return vrend_renderer_transfer_write_iov(ctx, res, iov, num_iovs,
@@ -8720,6 +8725,7 @@ void vrend_renderer_get_rect(int res_handle, struct iovec *iov, unsigned int num
    transfer_info.handle = res->handle;
    transfer_info.iovec = iov;
    transfer_info.iovec_cnt = num_iovs;
+   transfer_info.context0 = true;
    vrend_renderer_transfer_iov(&transfer_info, VREND_TRANSFER_READ);
 }
 

src/vrend_renderer.h

@@ -95,6 +95,7 @@ struct vrend_transfer_info {
    unsigned int iovec_cnt;
    struct iovec *iovec;
    uint64_t offset;
+   bool context0;
    struct pipe_box *box;
 };