diff --git a/src/gallium/drivers/i915/intel_winsys.h b/src/gallium/drivers/i915/intel_winsys.h
index 42c5e7470ec..2c8dc63f3f9 100644
--- a/src/gallium/drivers/i915/intel_winsys.h
+++ b/src/gallium/drivers/i915/intel_winsys.h
@@ -153,13 +153,13 @@ struct intel_winsys {
    /**
     * Write to a buffer.
     *
-    * Arguments follows pwrite(2)
+    * Arguments follows pipe_buffer_write.
     */
    int (*buffer_write)(struct intel_winsys *iws,
                        struct intel_buffer *dst,
-                       const void *src,
+                       size_t offset,
                        size_t size,
-                       size_t offset);
+                       const void *data);
 
    void (*buffer_destroy)(struct intel_winsys *iws,
                           struct intel_buffer *buffer);
diff --git a/src/gallium/winsys/drm/intel/gem/intel_drm_buffer.c b/src/gallium/winsys/drm/intel/gem/intel_drm_buffer.c
index 327e19fcd68..ac4dd6e00e9 100644
--- a/src/gallium/winsys/drm/intel/gem/intel_drm_buffer.c
+++ b/src/gallium/winsys/drm/intel/gem/intel_drm_buffer.c
@@ -119,9 +119,9 @@ intel_drm_buffer_unmap(struct intel_winsys *iws,
 static int
 intel_drm_buffer_write(struct intel_winsys *iws,
                        struct intel_buffer *buffer,
-                       const void *data,
+                       size_t offset,
                        size_t size,
-                       size_t offset)
+                       const void *data)
 {
    struct intel_drm_buffer *buf = intel_drm_buffer(buffer);