drm/i915: Fix set_caching locking

On the EINVAL case we don't release struct_mutex. It should be safe to
grab the lock after checking the parameters, which also resolves the
issues.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 365a7dc8a4a8..76bbb379d389 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3218,10 +3218,6 @@ int i915_gem_set_caching_ioctl(struct drm_device *dev, void *data,
         enum i915_cache_level level;
         int ret;
 
-        ret = i915_mutex_lock_interruptible(dev);
-        if (ret)
-                return ret;
-
         switch (args->caching) {
         case I915_CACHING_NONE:
                 level = I915_CACHE_NONE;
@@ -3233,6 +3229,10 @@ int i915_gem_set_caching_ioctl(struct drm_device *dev, void *data,
                 return -EINVAL;
         }
 
+        ret = i915_mutex_lock_interruptible(dev);
+        if (ret)
+                return ret;
+
         obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle));
         if (&obj->base == NULL) {
                 ret = -ENOENT;