drm/i915: fix up locking inconsistency around gem_do_init

The locking in our setup and teardown paths is rather arbitrary, but
generally we try to protect gem stuff with dev->struct_mutex. Further,
the ums/gem ioctl to setup gem _does_ take the look. So fix up this
benign inconsistency.

Notice while reading through code.

v2: Rebased on top of the ppgtt code.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 38dfcf91f400332af1ea9641699d375d9384c33f..39728fbb3f07f17d9bc25cc1422b4f9cf5a63331 100644 (file)
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1196,6 +1196,7 @@ static int i915_load_gem_init(struct drm_device *dev)
        /* Basic memrange allocator for stolen space */
        drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);
 
+       mutex_lock(&dev->struct_mutex);
        if (i915_enable_ppgtt && HAS_ALIASING_PPGTT(dev)) {
                /* PPGTT pdes are stolen from global gtt ptes, so shrink the
                 * aperture accordingly when using aliasing ppgtt. */
@@ -1222,7 +1223,6 @@ static int i915_load_gem_init(struct drm_device *dev)
                i915_gem_do_init(dev, 0, mappable_size, gtt_size - PAGE_SIZE);
        }
 
-       mutex_lock(&dev->struct_mutex);
        ret = i915_gem_init_hw(dev);
        mutex_unlock(&dev->struct_mutex);
        if (ret) {