7 files changed, 35 insertions, 5 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 21208a865380..d776d43707e0 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -232,7 +232,7 @@ static void i915_gem_context_free(struct i915_gem_context *ctx)
 	i915_ppgtt_put(ctx->ppgtt);
 
 	rbtree_postorder_for_each_entry_safe(it, n, &ctx->hw_contexts, node)
-		it->ops->destroy(it);
+		intel_context_put(it);
 
 	kfree(ctx->name);
 	put_pid(ctx->pid);
diff --git a/drivers/gpu/drm/i915/intel_context.c b/drivers/gpu/drm/i915/intel_context.c
index 0ab894a058f6..8931e0fee873 100644
--- a/drivers/gpu/drm/i915/intel_context.c
+++ b/drivers/gpu/drm/i915/intel_context.c
@@ -172,6 +172,7 @@ intel_context_pin(struct i915_gem_context *ctx,
 		list_add(&ce->active_link, &ctx->active_engines);
 		mutex_unlock(&ctx->mutex);
 
+		intel_context_get(ce);
 		smp_mb__before_atomic(); /* flush pin before it is visible */
 	}
 
@@ -192,6 +193,7 @@ void intel_context_unpin(struct intel_context *ce)
 		return;
 
 	/* We may be called from inside intel_context_pin() to evict another */
+	intel_context_get(ce);
 	mutex_lock_nested(&ce->pin_mutex, SINGLE_DEPTH_NESTING);
 
 	if (likely(atomic_dec_and_test(&ce->pin_count))) {
@@ -202,9 +204,11 @@ void intel_context_unpin(struct intel_context *ce)
 		mutex_unlock(&ce->gem_context->mutex);
 
 		i915_gem_context_put(ce->gem_context);
+		intel_context_put(ce);
 	}
 
 	mutex_unlock(&ce->pin_mutex);
+	intel_context_put(ce);
 }
 
 static void intel_context_retire(struct i915_active_request *active,
@@ -221,6 +225,8 @@ intel_context_init(struct intel_context *ce,
 		   struct i915_gem_context *ctx,
 		   struct intel_engine_cs *engine)
 {
+	kref_init(&ce->ref);
+
 	ce->gem_context = ctx;
 	ce->engine = engine;
 	ce->ops = engine->cops;
diff --git a/drivers/gpu/drm/i915/intel_context.h b/drivers/gpu/drm/i915/intel_context.h
index 9546d932406a..ebc861b1a49e 100644
--- a/drivers/gpu/drm/i915/intel_context.h
+++ b/drivers/gpu/drm/i915/intel_context.h
@@ -73,4 +73,15 @@ static inline void __intel_context_pin(struct intel_context *ce)
 
 void intel_context_unpin(struct intel_context *ce);
 
+static inline struct intel_context *intel_context_get(struct intel_context *ce)
+{
+	kref_get(&ce->ref);
+	return ce;
+}
+
+static inline void intel_context_put(struct intel_context *ce)
+{
+	kref_put(&ce->ref, ce->ops->destroy);
+}
+
 #endif /* __INTEL_CONTEXT_H__ */
diff --git a/drivers/gpu/drm/i915/intel_context_types.h b/drivers/gpu/drm/i915/intel_context_types.h
index 6dc9b4b9067b..624729a35875 100644
--- a/drivers/gpu/drm/i915/intel_context_types.h
+++ b/drivers/gpu/drm/i915/intel_context_types.h
@@ -7,6 +7,7 @@
 #ifndef __INTEL_CONTEXT_TYPES__
 #define __INTEL_CONTEXT_TYPES__
 
+#include <linux/kref.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/rbtree.h>
@@ -22,7 +23,8 @@ struct intel_ring;
 struct intel_context_ops {
 	int (*pin)(struct intel_context *ce);
 	void (*unpin)(struct intel_context *ce);
-	void (*destroy)(struct intel_context *ce);
+
+	void (*destroy)(struct kref *kref);
 };
 
 /*
@@ -36,6 +38,8 @@ struct intel_sseu {
 };
 
 struct intel_context {
+	struct kref ref;
+
 	struct i915_gem_context *gem_context;
 	struct intel_engine_cs *engine;
 	struct intel_engine_cs *active;
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index c949af7be8bd..51c2ea164b36 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1236,8 +1236,10 @@ static void __execlists_context_fini(struct intel_context *ce)
 	i915_gem_object_put(ce->state->obj);
 }
 
-static void execlists_context_destroy(struct intel_context *ce)
+static void execlists_context_destroy(struct kref *kref)
 {
+	struct intel_context *ce = container_of(kref, typeof(*ce), ref);
+
 	GEM_BUG_ON(intel_context_is_pinned(ce));
 
 	if (ce->state)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 81b32bac2bcd..9e7ad17b5250 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1350,8 +1350,10 @@ static void __ring_context_fini(struct intel_context *ce)
 	i915_gem_object_put(ce->state->obj);
 }
 
-static void ring_context_destroy(struct intel_context *ce)
+static void ring_context_destroy(struct kref *ref)
 {
+	struct intel_context *ce = container_of(ref, typeof(*ce), ref);
+
 	GEM_BUG_ON(intel_context_is_pinned(ce));
 
 	if (ce->state)
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index 7641b74ada98..639d36eb904a 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -128,12 +128,16 @@ static void mock_context_unpin(struct intel_context *ce)
 	mock_timeline_unpin(ce->ring->timeline);
 }
 
-static void mock_context_destroy(struct intel_context *ce)
+static void mock_context_destroy(struct kref *ref)
 {
+	struct intel_context *ce = container_of(ref, typeof(*ce), ref);
+
 	GEM_BUG_ON(intel_context_is_pinned(ce));
 
 	if (ce->ring)
 		mock_ring_free(ce->ring);
+
+	intel_context_free(ce);
 }
 
 static int mock_context_pin(struct intel_context *ce)
@@ -151,6 +155,7 @@ static int mock_context_pin(struct intel_context *ce)
 static const struct intel_context_ops mock_context_ops = {
 	.pin = mock_context_pin,
 	.unpin = mock_context_unpin,
+
 	.destroy = mock_context_destroy,
 };