1 files changed, 25 insertions, 6 deletions

diff --git a/src/gallium/drivers/r300/r300_render.c b/src/gallium/drivers/r300/r300_render.c
index b4197e03520..f58d511e11b 100644
--- a/src/gallium/drivers/r300/r300_render.c
+++ b/src/gallium/drivers/r300/r300_render.c
@@ -425,7 +425,7 @@ static void r300_emit_draw_arrays_immediate(struct r300_context *r300,
 
         if (transfer[vbi]) {
             vbuf = &r300->vertex_buffer[vbi];
-            pipe_buffer_unmap(&r300->context, vbuf->buffer, transfer[vbi]);
+            pipe_buffer_unmap(&r300->context, transfer[vbi]);
             transfer[vbi] = NULL;
         }
     }
@@ -551,7 +551,27 @@ static void r300_draw_range_elements(struct pipe_context* pipe,
                                 &start, count);
 
     r300_update_derived_state(r300);
-    r300_upload_index_buffer(r300, &indexBuffer, indexSize, start, count, &new_offset);
+
+    /* Fallback for misaligned ushort indices. */
+    if (indexSize == 2 && start % 2 == 1) {
+        struct pipe_transfer *transfer;
+        struct pipe_resource *userbuf;
+        uint16_t *ptr = pipe_buffer_map(pipe, indexBuffer,
+                                        PIPE_TRANSFER_READ, &transfer);
+
+        /* Copy the mapped index buffer directly to the upload buffer.
+         * The start index will be aligned simply from the fact that
+         * every sub-buffer in u_upload_mgr is aligned. */
+        userbuf = pipe->screen->user_buffer_create(pipe->screen,
+                                                   ptr + start, count * 2,
+                                                   PIPE_BIND_INDEX_BUFFER);
+        indexBuffer = userbuf;
+        r300_upload_index_buffer(r300, &indexBuffer, indexSize, 0, count, &new_offset);
+        pipe_resource_reference(&userbuf, NULL);
+        pipe_buffer_unmap(pipe, transfer);
+    } else {
+        r300_upload_index_buffer(r300, &indexBuffer, indexSize, start, count, &new_offset);
+    }
 
     start = new_offset;
 
@@ -750,14 +770,13 @@ static void r300_swtcl_draw_vbo(struct pipe_context* pipe,
 
     for (i = 0; i < r300->vertex_buffer_count; i++) {
         if (r300->vertex_buffer[i].buffer) {
-            pipe_buffer_unmap(pipe, r300->vertex_buffer[i].buffer,
-                              vb_transfer[i]);
+            pipe_buffer_unmap(pipe, vb_transfer[i]);
             draw_set_mapped_vertex_buffer(r300->draw, i, NULL);
         }
     }
 
     if (indexed) {
-        pipe_buffer_unmap(pipe, r300->index_buffer.buffer, ib_transfer);
+        pipe_buffer_unmap(pipe, ib_transfer);
         draw_set_mapped_index_buffer(r300->draw, NULL);
     }
 }
@@ -857,7 +876,7 @@ static void r300_render_unmap_vertices(struct vbuf_render* render,
 
     r300render->vbo_max_used = MAX2(r300render->vbo_max_used,
                                     r300render->vertex_size * (max + 1));
-    pipe_buffer_unmap(context, r300->vbo, r300render->vbo_transfer);
+    pipe_buffer_unmap(context, r300render->vbo_transfer);
 
     r300render->vbo_transfer = NULL;
 }