radeonsi: mark buffer texture range valid for shader images

When a shader image view into a buffer texture can be written to, the buffer's
valid range must be updated, or subsequent transfers may incorrectly skip
synchronization.

This fixes a bug that was exposed in Xephyr by PBO acceleration for glReadPixels,
reported by Michel Dänzer.

Cc: Michel Dänzer <michel.daenzer@amd.com>
Cc: 12.0 <mesa-stable@lists.freedesktop.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

diff --git a/src/gallium/drivers/radeonsi/si_descriptors.c b/src/gallium/drivers/radeonsi/si_descriptors.c
index 71f4d71..d66996a 100644 (file)
--- a/src/gallium/drivers/radeonsi/si_descriptors.c
+++ b/src/gallium/drivers/radeonsi/si_descriptors.c
@@ -512,6 +512,23 @@ si_disable_shader_image(struct si_images_info *images, unsigned slot)
        }
 }
 
+static void
+si_mark_image_range_valid(struct pipe_image_view *view)
+{
+       struct r600_resource *res = (struct r600_resource *)view->resource;
+       const struct util_format_description *desc;
+       unsigned stride;
+
+       assert(res && res->b.b.target == PIPE_BUFFER);
+
+       desc = util_format_description(view->format);
+       stride = desc->block.bits / 8;
+
+       util_range_add(&res->valid_buffer_range,
+                      stride * (view->u.buf.first_element),
+                      stride * (view->u.buf.last_element + 1));
+}
+
 static void si_set_shader_image(struct si_context *ctx,
                                struct si_images_info *images,
                                unsigned slot, struct pipe_image_view *view)
@@ -533,6 +550,9 @@ static void si_set_shader_image(struct si_context *ctx,
                                   RADEON_USAGE_READWRITE);
 
        if (res->b.b.target == PIPE_BUFFER) {
+               if (view->access & PIPE_IMAGE_ACCESS_WRITE)
+                       si_mark_image_range_valid(view);
+
                si_make_buffer_descriptor(screen, res,
                                          view->format,
                                          view->u.buf.first_element,
@@ -1361,6 +1381,9 @@ static void si_invalidate_buffer(struct pipe_context *ctx, struct pipe_resource
                        unsigned i = u_bit_scan(&mask);
 
                        if (images->views[i].resource == buf) {
+                               if (images->views[i].access & PIPE_IMAGE_ACCESS_WRITE)
+                                       si_mark_image_range_valid(&images->views[i]);
+
                                si_desc_reset_buffer_offset(
                                        ctx, images->desc.list + i * 8 + 4,
                                        old_va, buf);