drm/i915: Move GraphicsTechnology files under gt/

Start partitioning off the code that talks to the hardware (GT) from the
uapi layers and move the device facing code under gt/

One casualty is s/intel_ringbuffer.h/intel_engine.h/ with the plan to
subdivide that header and body further (and split out the submission
code from the ringbuffer and logical context handling). This patch aims
to be simple motion so git can fixup inflight patches with little mess.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190424174839.7141-1-chris@chris-wilson.co.uk

1 files changed, 268 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
new file mode 100644
index 000000000000..ebd1e5919a4a
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -0,0 +1,268 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include "i915_drv.h"
+#include "i915_gem_context.h"
+#include "i915_globals.h"
+
+#include "intel_context.h"
+#include "intel_engine.h"
+
+static struct i915_global_context {
+	struct i915_global base;
+	struct kmem_cache *slab_ce;
+} global;
+
+struct intel_context *intel_context_alloc(void)
+{
+	return kmem_cache_zalloc(global.slab_ce, GFP_KERNEL);
+}
+
+void intel_context_free(struct intel_context *ce)
+{
+	kmem_cache_free(global.slab_ce, ce);
+}
+
+struct intel_context *
+intel_context_lookup(struct i915_gem_context *ctx,
+		     struct intel_engine_cs *engine)
+{
+	struct intel_context *ce = NULL;
+	struct rb_node *p;
+
+	spin_lock(&ctx->hw_contexts_lock);
+	p = ctx->hw_contexts.rb_node;
+	while (p) {
+		struct intel_context *this =
+			rb_entry(p, struct intel_context, node);
+
+		if (this->engine == engine) {
+			GEM_BUG_ON(this->gem_context != ctx);
+			ce = this;
+			break;
+		}
+
+		if (this->engine < engine)
+			p = p->rb_right;
+		else
+			p = p->rb_left;
+	}
+	spin_unlock(&ctx->hw_contexts_lock);
+
+	return ce;
+}
+
+struct intel_context *
+__intel_context_insert(struct i915_gem_context *ctx,
+		       struct intel_engine_cs *engine,
+		       struct intel_context *ce)
+{
+	struct rb_node **p, *parent;
+	int err = 0;
+
+	spin_lock(&ctx->hw_contexts_lock);
+
+	parent = NULL;
+	p = &ctx->hw_contexts.rb_node;
+	while (*p) {
+		struct intel_context *this;
+
+		parent = *p;
+		this = rb_entry(parent, struct intel_context, node);
+
+		if (this->engine == engine) {
+			err = -EEXIST;
+			ce = this;
+			break;
+		}
+
+		if (this->engine < engine)
+			p = &parent->rb_right;
+		else
+			p = &parent->rb_left;
+	}
+	if (!err) {
+		rb_link_node(&ce->node, parent, p);
+		rb_insert_color(&ce->node, &ctx->hw_contexts);
+	}
+
+	spin_unlock(&ctx->hw_contexts_lock);
+
+	return ce;
+}
+
+void __intel_context_remove(struct intel_context *ce)
+{
+	struct i915_gem_context *ctx = ce->gem_context;
+
+	spin_lock(&ctx->hw_contexts_lock);
+	rb_erase(&ce->node, &ctx->hw_contexts);
+	spin_unlock(&ctx->hw_contexts_lock);
+}
+
+static struct intel_context *
+intel_context_instance(struct i915_gem_context *ctx,
+		       struct intel_engine_cs *engine)
+{
+	struct intel_context *ce, *pos;
+
+	ce = intel_context_lookup(ctx, engine);
+	if (likely(ce))
+		return ce;
+
+	ce = intel_context_alloc();
+	if (!ce)
+		return ERR_PTR(-ENOMEM);
+
+	intel_context_init(ce, ctx, engine);
+
+	pos = __intel_context_insert(ctx, engine, ce);
+	if (unlikely(pos != ce)) /* Beaten! Use their HW context instead */
+		intel_context_free(ce);
+
+	GEM_BUG_ON(intel_context_lookup(ctx, engine) != pos);
+	return pos;
+}
+
+struct intel_context *
+intel_context_pin_lock(struct i915_gem_context *ctx,
+		       struct intel_engine_cs *engine)
+	__acquires(ce->pin_mutex)
+{
+	struct intel_context *ce;
+
+	ce = intel_context_instance(ctx, engine);
+	if (IS_ERR(ce))
+		return ce;
+
+	if (mutex_lock_interruptible(&ce->pin_mutex))
+		return ERR_PTR(-EINTR);
+
+	return ce;
+}
+
+struct intel_context *
+intel_context_pin(struct i915_gem_context *ctx,
+		  struct intel_engine_cs *engine)
+{
+	struct intel_context *ce;
+	int err;
+
+	ce = intel_context_instance(ctx, engine);
+	if (IS_ERR(ce))
+		return ce;
+
+	if (likely(atomic_inc_not_zero(&ce->pin_count)))
+		return ce;
+
+	if (mutex_lock_interruptible(&ce->pin_mutex))
+		return ERR_PTR(-EINTR);
+
+	if (likely(!atomic_read(&ce->pin_count))) {
+		err = ce->ops->pin(ce);
+		if (err)
+			goto err;
+
+		i915_gem_context_get(ctx);
+		GEM_BUG_ON(ce->gem_context != ctx);
+
+		mutex_lock(&ctx->mutex);
+		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 */
+	}
+
+	atomic_inc(&ce->pin_count);
+	GEM_BUG_ON(!intel_context_is_pinned(ce)); /* no overflow! */
+
+	mutex_unlock(&ce->pin_mutex);
+	return ce;
+
+err:
+	mutex_unlock(&ce->pin_mutex);
+	return ERR_PTR(err);
+}
+
+void intel_context_unpin(struct intel_context *ce)
+{
+	if (likely(atomic_add_unless(&ce->pin_count, -1, 1)))
+		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))) {
+		ce->ops->unpin(ce);
+
+		mutex_lock(&ce->gem_context->mutex);
+		list_del(&ce->active_link);
+		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,
+				 struct i915_request *rq)
+{
+	struct intel_context *ce =
+		container_of(active, typeof(*ce), active_tracker);
+
+	intel_context_unpin(ce);
+}
+
+void
+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;
+	ce->sseu = engine->sseu;
+
+	INIT_LIST_HEAD(&ce->signal_link);
+	INIT_LIST_HEAD(&ce->signals);
+
+	mutex_init(&ce->pin_mutex);
+
+	i915_active_request_init(&ce->active_tracker,
+				 NULL, intel_context_retire);
+}
+
+static void i915_global_context_shrink(void)
+{
+	kmem_cache_shrink(global.slab_ce);
+}
+
+static void i915_global_context_exit(void)
+{
+	kmem_cache_destroy(global.slab_ce);
+}
+
+static struct i915_global_context global = { {
+	.shrink = i915_global_context_shrink,
+	.exit = i915_global_context_exit,
+} };
+
+int __init i915_global_context_init(void)
+{
+	global.slab_ce = KMEM_CACHE(intel_context, SLAB_HWCACHE_ALIGN);
+	if (!global.slab_ce)
+		return -ENOMEM;
+
+	i915_global_register(&global.base);
+	return 0;
+}