diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 18201852d68d..d3fb2e3781af 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -75,6 +75,7 @@ gt-y += \
 	gt/intel_engine_cs.o \
 	gt/intel_engine_heartbeat.o \
 	gt/intel_engine_pm.o \
+	gt/intel_engine_user.o \
 	gt/intel_gt.o \
 	gt/intel_gt_pm.o \
 	gt/intel_lrc.o \
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 18b226bc5e3a..e31431fa141e 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -70,6 +70,7 @@
 #include <drm/i915_drm.h>
 
 #include "gt/intel_lrc_reg.h"
+#include "gt/intel_engine_user.h"
 
 #include "i915_gem_context.h"
 #include "i915_globals.h"
@@ -1740,7 +1741,7 @@ get_engines(struct i915_gem_context *ctx,
 
 		if (e->engines[n]) {
 			ci.engine_class = e->engines[n]->engine->uabi_class;
-			ci.engine_instance = e->engines[n]->engine->instance;
+			ci.engine_instance = e->engines[n]->engine->uabi_instance;
 		}
 
 		if (copy_to_user(&user->engines[n], &ci, sizeof(ci))) {
diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h
index 38eeb4320c97..f0ad33929987 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine.h
@@ -400,9 +400,6 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 		       struct drm_printer *m,
 		       const char *header, ...);
 
-struct intel_engine_cs *
-intel_engine_lookup_user(struct drm_i915_private *i915, u8 class, u8 instance);
-
 static inline void intel_engine_context_in(struct intel_engine_cs *engine)
 {
 	unsigned long flags;
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 89f4a3825b77..5935702478ca 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -32,6 +32,7 @@
 
 #include "intel_engine.h"
 #include "intel_engine_pm.h"
+#include "intel_engine_user.h"
 #include "intel_context.h"
 #include "intel_lrc.h"
 #include "intel_reset.h"
@@ -285,9 +286,7 @@ static void intel_engine_sanitize_mmio(struct intel_engine_cs *engine)
 	intel_engine_set_hwsp_writemask(engine, ~0u);
 }
 
-static int
-intel_engine_setup(struct drm_i915_private *dev_priv,
-		   enum intel_engine_id id)
+static int intel_engine_setup(struct intel_gt *gt, enum intel_engine_id id)
 {
 	const struct engine_info *info = &intel_engines[id];
 	struct intel_engine_cs *engine;
@@ -303,10 +302,9 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 	if (GEM_DEBUG_WARN_ON(info->instance > MAX_ENGINE_INSTANCE))
 		return -EINVAL;
 
-	if (GEM_DEBUG_WARN_ON(dev_priv->engine_class[info->class][info->instance]))
+	if (GEM_DEBUG_WARN_ON(gt->engine_class[info->class][info->instance]))
 		return -EINVAL;
 
-	GEM_BUG_ON(dev_priv->engine[id]);
 	engine = kzalloc(sizeof(*engine), GFP_KERNEL);
 	if (!engine)
 		return -ENOMEM;
@@ -315,12 +313,12 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 
 	engine->id = id;
 	engine->mask = BIT(id);
-	engine->i915 = dev_priv;
-	engine->gt = &dev_priv->gt;
-	engine->uncore = &dev_priv->uncore;
+	engine->i915 = gt->i915;
+	engine->gt = gt;
+	engine->uncore = gt->uncore;
 	__sprint_engine_name(engine->name, info);
 	engine->hw_id = engine->guc_id = info->hw_id;
-	engine->mmio_base = __engine_mmio_base(dev_priv, info->mmio_bases);
+	engine->mmio_base = __engine_mmio_base(gt->i915, info->mmio_bases);
 	engine->class = info->class;
 	engine->instance = info->instance;
 
@@ -331,13 +329,14 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 	engine->destroy = (typeof(engine->destroy))kfree;
 
 	engine->uabi_class = intel_engine_classes[info->class].uabi_class;
+	engine->uabi_instance = info->instance;
 
-	engine->context_size = intel_engine_context_size(dev_priv,
+	engine->context_size = intel_engine_context_size(gt->i915,
 							 engine->class);
 	if (WARN_ON(engine->context_size > BIT(20)))
 		engine->context_size = 0;
 	if (engine->context_size)
-		DRIVER_CAPS(dev_priv)->has_logical_contexts = true;
+		DRIVER_CAPS(gt->i915)->has_logical_contexts = true;
 
 	/* Nothing to do here, execute in order of dependencies */
 	engine->schedule = NULL;
@@ -349,8 +348,11 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 	/* Scrub mmio state on takeover */
 	intel_engine_sanitize_mmio(engine);
 
-	dev_priv->engine_class[info->class][info->instance] = engine;
-	dev_priv->engine[id] = engine;
+	engine->gt->engine_class[info->class][info->instance] = engine;
+
+	intel_engine_add_user(engine);
+	gt->i915->engine[id] = engine;
+
 	return 0;
 }
 
@@ -433,7 +435,7 @@ int intel_engines_init_mmio(struct drm_i915_private *i915)
 		if (!HAS_ENGINE(i915, i))
 			continue;
 
-		err = intel_engine_setup(i915, i);
+		err = intel_engine_setup(&i915->gt, i);
 		if (err)
 			goto cleanup;
 
@@ -1505,29 +1507,6 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 	intel_engine_print_breadcrumbs(engine, m);
 }
 
-static u8 user_class_map[] = {
-	[I915_ENGINE_CLASS_RENDER] = RENDER_CLASS,
-	[I915_ENGINE_CLASS_COPY] = COPY_ENGINE_CLASS,
-	[I915_ENGINE_CLASS_VIDEO] = VIDEO_DECODE_CLASS,
-	[I915_ENGINE_CLASS_VIDEO_ENHANCE] = VIDEO_ENHANCEMENT_CLASS,
-};
-
-struct intel_engine_cs *
-intel_engine_lookup_user(struct drm_i915_private *i915, u8 class, u8 instance)
-{
-	if (class >= ARRAY_SIZE(user_class_map))
-		return NULL;
-
-	class = user_class_map[class];
-
-	GEM_BUG_ON(class > MAX_ENGINE_CLASS);
-
-	if (instance > MAX_ENGINE_INSTANCE)
-		return NULL;
-
-	return i915->engine_class[class][instance];
-}
-
 /**
  * intel_enable_engine_stats() - Enable engine busy tracking on engine
  * @engine: engine to enable stats collection
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
index 9a3ead556743..0ef07ada0ae7 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
@@ -12,6 +12,7 @@
 #include <linux/kref.h>
 #include <linux/list.h>
 #include <linux/llist.h>
+#include <linux/rbtree.h>
 #include <linux/timer.h>
 #include <linux/types.h>
 #include <linux/workqueue.h>
@@ -260,15 +261,19 @@ struct intel_engine_cs {
 	unsigned int guc_id;
 	intel_engine_mask_t mask;
 
-	u8 uabi_class;
-
 	u8 class;
 	u8 instance;
+
+	u8 uabi_class;
+	u8 uabi_instance;
+
 	u32 context_size;
 	u32 mmio_base;
 
 	u32 uabi_capabilities;
 
+	struct rb_node uabi_node;
+
 	struct intel_sseu sseu;
 
 	struct intel_ring *buffer;
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.c b/drivers/gpu/drm/i915/gt/intel_engine_user.c
new file mode 100644
index 000000000000..f74fb4d2fa0d
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_engine_user.c
@@ -0,0 +1,66 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include "i915_drv.h"
+#include "intel_engine.h"
+#include "intel_engine_user.h"
+
+struct intel_engine_cs *
+intel_engine_lookup_user(struct drm_i915_private *i915, u8 class, u8 instance)
+{
+	struct rb_node *p = i915->uabi_engines.rb_node;
+
+	while (p) {
+		struct intel_engine_cs *it =
+			rb_entry(p, typeof(*it), uabi_node);
+
+		if (class < it->uabi_class)
+			p = p->rb_left;
+		else if (class > it->uabi_class ||
+			 instance > it->uabi_instance)
+			p = p->rb_right;
+		else if (instance < it->uabi_instance)
+			p = p->rb_left;
+		else
+			return it;
+	}
+
+	return NULL;
+}
+
+void intel_engine_add_user(struct intel_engine_cs *engine)
+{
+	struct rb_root *root = &engine->i915->uabi_engines;
+	struct rb_node **p, *parent;
+
+	parent = NULL;
+	p = &root->rb_node;
+	while (*p) {
+		struct intel_engine_cs *it;
+
+		parent = *p;
+		it = rb_entry(parent, typeof(*it), uabi_node);
+
+		/* All user class:instance identifiers must be unique */
+		GEM_BUG_ON(it->uabi_class == engine->uabi_class &&
+			   it->uabi_instance == engine->uabi_instance);
+
+		if (engine->uabi_class < it->uabi_class)
+			p = &parent->rb_left;
+		else if (engine->uabi_class > it->uabi_class ||
+			 engine->uabi_instance > it->uabi_instance)
+			p = &parent->rb_right;
+		else
+			p = &parent->rb_left;
+	}
+
+	rb_link_node(&engine->uabi_node, parent, p);
+	rb_insert_color(&engine->uabi_node, root);
+
+	GEM_BUG_ON(intel_engine_lookup_user(engine->i915,
+					    engine->uabi_class,
+					    engine->uabi_instance) != engine);
+}
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.h b/drivers/gpu/drm/i915/gt/intel_engine_user.h
new file mode 100644
index 000000000000..091dc8a4a39f
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_engine_user.h
@@ -0,0 +1,20 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef INTEL_ENGINE_USER_H
+#define INTEL_ENGINE_USER_H
+
+#include <linux/types.h>
+
+struct drm_i915_private;
+struct intel_engine_cs;
+
+struct intel_engine_cs *
+intel_engine_lookup_user(struct drm_i915_private *i915, u8 class, u8 instance);
+
+void intel_engine_add_user(struct intel_engine_cs *engine);
+
+#endif /* INTEL_ENGINE_USER_H */
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_types.h b/drivers/gpu/drm/i915/gt/intel_gt_types.h
index 0112bb98cbf3..5fa7bf793f0f 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_types.h
@@ -21,6 +21,7 @@
 
 struct drm_i915_private;
 struct i915_ggtt;
+struct intel_engine_cs;
 struct intel_uncore;
 
 struct intel_gt {
@@ -67,6 +68,9 @@ struct intel_gt {
 	u32 pm_ier;
 
 	u32 pm_guc_events;
+
+	struct intel_engine_cs *engine_class[MAX_ENGINE_CLASS + 1]
+					    [MAX_ENGINE_INSTANCE + 1];
 };
 
 enum intel_gt_scratch_field {
diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c
index 60f27e52d267..eb40a58665be 100644
--- a/drivers/gpu/drm/i915/gt/selftest_lrc.c
+++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c
@@ -1773,6 +1773,7 @@ static int live_virtual_engine(void *arg)
 	struct drm_i915_private *i915 = arg;
 	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
 	struct intel_engine_cs *engine;
+	struct intel_gt *gt = &i915->gt;
 	enum intel_engine_id id;
 	unsigned int class, inst;
 	int err = -ENODEV;
@@ -1796,10 +1797,10 @@ static int live_virtual_engine(void *arg)
 
 		nsibling = 0;
 		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
-			if (!i915->engine_class[class][inst])
+			if (!gt->engine_class[class][inst])
 				continue;
 
-			siblings[nsibling++] = i915->engine_class[class][inst];
+			siblings[nsibling++] = gt->engine_class[class][inst];
 		}
 		if (nsibling < 2)
 			continue;
@@ -1920,6 +1921,7 @@ static int live_virtual_mask(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
 	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
+	struct intel_gt *gt = &i915->gt;
 	unsigned int class, inst;
 	int err = 0;
 
@@ -1933,10 +1935,10 @@ static int live_virtual_mask(void *arg)
 
 		nsibling = 0;
 		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
-			if (!i915->engine_class[class][inst])
+			if (!gt->engine_class[class][inst])
 				break;
 
-			siblings[nsibling++] = i915->engine_class[class][inst];
+			siblings[nsibling++] = gt->engine_class[class][inst];
 		}
 		if (nsibling < 2)
 			continue;
@@ -2097,6 +2099,7 @@ static int live_virtual_bond(void *arg)
 	};
 	struct drm_i915_private *i915 = arg;
 	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
+	struct intel_gt *gt = &i915->gt;
 	unsigned int class, inst;
 	int err = 0;
 
@@ -2111,11 +2114,11 @@ static int live_virtual_bond(void *arg)
 
 		nsibling = 0;
 		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
-			if (!i915->engine_class[class][inst])
+			if (!gt->engine_class[class][inst])
 				break;
 
 			GEM_BUG_ON(nsibling == ARRAY_SIZE(siblings));
-			siblings[nsibling++] = i915->engine_class[class][inst];
+			siblings[nsibling++] = gt->engine_class[class][inst];
 		}
 		if (nsibling < 2)
 			continue;
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ab548ec3da1c..58b1ef5f2ce0 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1371,11 +1371,12 @@ struct drm_i915_private {
 	wait_queue_head_t gmbus_wait_queue;
 
 	struct pci_dev *bridge_dev;
-	struct intel_engine_cs *engine[I915_NUM_ENGINES];
+
 	/* Context used internally to idle the GPU and setup initial state */
 	struct i915_gem_context *kernel_context;
-	struct intel_engine_cs *engine_class[MAX_ENGINE_CLASS + 1]
-					    [MAX_ENGINE_INSTANCE + 1];
+
+	struct intel_engine_cs *engine[I915_NUM_ENGINES];
+	struct rb_root uabi_engines;
 
 	struct resource mch_res;
 
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index a17d4fd17962..7b19d7df9ba1 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -3109,7 +3109,7 @@ gen11_engine_irq_handler(struct intel_gt *gt, const u8 class,
 	struct intel_engine_cs *engine;
 
 	if (instance <= MAX_ENGINE_INSTANCE)
-		engine = gt->i915->engine_class[class][instance];
+		engine = gt->engine_class[class][instance];
 	else
 		engine = NULL;
 
diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index eff86483bec0..bdf7963a043b 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -8,6 +8,7 @@
 #include <linux/pm_runtime.h>
 
 #include "gt/intel_engine.h"
+#include "gt/intel_engine_user.h"
 
 #include "i915_drv.h"
 #include "i915_pmu.h"
@@ -926,7 +927,7 @@ create_event_attributes(struct drm_i915_private *i915)
 			i915_iter =
 				add_i915_attr(i915_iter, str,
 					      __I915_PMU_ENGINE(engine->uabi_class,
-								engine->instance,
+								engine->uabi_instance,
 								engine_events[i].sample));
 
 			str = kasprintf(GFP_KERNEL, "%s-%s.unit",
diff --git a/drivers/gpu/drm/i915/i915_query.c b/drivers/gpu/drm/i915/i915_query.c
index 7b7016171057..70b1ad38e615 100644
--- a/drivers/gpu/drm/i915/i915_query.c
+++ b/drivers/gpu/drm/i915/i915_query.c
@@ -127,7 +127,7 @@ query_engine_info(struct drm_i915_private *i915,
 
 	for_each_engine(engine, i915, id) {
 		info.engine.engine_class = engine->uabi_class;
-		info.engine.engine_instance = engine->instance;
+		info.engine.engine_instance = engine->uabi_instance;
 		info.capabilities = engine->uabi_capabilities;
 
 		if (__copy_to_user(info_ptr, &info, sizeof(info)))
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index da18b8d6b80c..1d11245c4c87 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -677,7 +677,7 @@ TRACE_EVENT(i915_request_queue,
 			   __entry->dev = rq->i915->drm.primary->index;
 			   __entry->hw_id = rq->gem_context->hw_id;
 			   __entry->class = rq->engine->uabi_class;
-			   __entry->instance = rq->engine->instance;
+			   __entry->instance = rq->engine->uabi_instance;
 			   __entry->ctx = rq->fence.context;
 			   __entry->seqno = rq->fence.seqno;
 			   __entry->flags = flags;
@@ -706,7 +706,7 @@ DECLARE_EVENT_CLASS(i915_request,
 			   __entry->dev = rq->i915->drm.primary->index;
 			   __entry->hw_id = rq->gem_context->hw_id;
 			   __entry->class = rq->engine->uabi_class;
-			   __entry->instance = rq->engine->instance;
+			   __entry->instance = rq->engine->uabi_instance;
 			   __entry->ctx = rq->fence.context;
 			   __entry->seqno = rq->fence.seqno;
 			   ),
@@ -751,7 +751,7 @@ TRACE_EVENT(i915_request_in,
 			   __entry->dev = rq->i915->drm.primary->index;
 			   __entry->hw_id = rq->gem_context->hw_id;
 			   __entry->class = rq->engine->uabi_class;
-			   __entry->instance = rq->engine->instance;
+			   __entry->instance = rq->engine->uabi_instance;
 			   __entry->ctx = rq->fence.context;
 			   __entry->seqno = rq->fence.seqno;
 			   __entry->prio = rq->sched.attr.priority;
@@ -782,7 +782,7 @@ TRACE_EVENT(i915_request_out,
 			   __entry->dev = rq->i915->drm.primary->index;
 			   __entry->hw_id = rq->gem_context->hw_id;
 			   __entry->class = rq->engine->uabi_class;
-			   __entry->instance = rq->engine->instance;
+			   __entry->instance = rq->engine->uabi_instance;
 			   __entry->ctx = rq->fence.context;
 			   __entry->seqno = rq->fence.seqno;
 			   __entry->completed = i915_request_completed(rq);
@@ -847,7 +847,7 @@ TRACE_EVENT(i915_request_wait_begin,
 			   __entry->dev = rq->i915->drm.primary->index;
 			   __entry->hw_id = rq->gem_context->hw_id;
 			   __entry->class = rq->engine->uabi_class;
-			   __entry->instance = rq->engine->instance;
+			   __entry->instance = rq->engine->uabi_instance;
 			   __entry->ctx = rq->fence.context;
 			   __entry->seqno = rq->fence.seqno;
 			   __entry->flags = flags;
