drm/i915: plumb VM into bind/unbind code

As alluded to in several patches, and it will be reiterated later... A
VMA is an abstraction for a GEM BO bound into an address space.
Therefore it stands to reason, that the existing bind, and unbind are
the ones which will be the most impacted. This patch implements this,
and updates all callers which weren't already updated in the series
(because it was too messy).

This patch represents the bulk of an earlier, larger patch. I've pulled
out a bunch of things by the request of Daniel. The history is preserved
for posterity with the email convention of ">" One big change from the
original patch aside from a bunch of cropping is I've created an
i915_vma_unbind() function. That is because we always have the VMA
anyway, and doing an extra lookup is useful. There is a caveat, we
retain an i915_gem_object_ggtt_unbind, for the global cases which might
not talk in VMAs.

> drm/i915: plumb VM into object operations
>
> This patch was formerly known as:
> "drm/i915: Create VMAs (part 3) - plumbing"
>
> This patch adds a VM argument, bind/unbind, and the object
> offset/size/color getters/setters. It preserves the old ggtt helper
> functions because things still need, and will continue to need them.
>
> Some code will still need to be ported over after this.
>
> v2: Fix purge to pick an object and unbind all vmas
> This was doable because of the global bound list change.
>
> v3: With the commit to actually pin/unpin pages in place, there is no
> longer a need to check if unbind succeeded before calling put_pages().
> Make put_pages only BUG() after checking pin count.
>
> v4: Rebased on top of the new hangcheck work by Mika
> plumbed eb_destroy also
> Many checkpatch related fixes
>
> v5: Very large rebase
>
> v6:
> Change BUG_ON to WARN_ON (Daniel)
> Rename vm to ggtt in preallocate stolen, since it is always ggtt when
> dealing with stolen memory. (Daniel)
> list_for_each will short-circuit already (Daniel)
> remove superflous space (Daniel)
> Use per object list of vmas (Daniel)
> Make obj_bound_any() use obj_bound for each vm (Ben)
> s/bind_to_gtt/bind_to_vm/ (Ben)
>
> Fixed up the inactive shrinker. As Daniel noticed the code could
> potentially count the same object multiple times. While it's not
> possible in the current case, since 1 object can only ever be bound into
> 1 address space thus far - we may as well try to get something more
> future proof in place now. With a prep patch before this to switch over
> to using the bound list + inactive check, we're now able to carry that
> forward for every address space an object is bound into.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Rebase on top of the loss of "drm/i915: Cleanup more of VMA
in destroy".]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -1800,7 +1800,7 @@ i915_drop_caches_set(void *data, u64 val)
 			if (obj->pin_count)
 				continue;
 
-			ret = i915_gem_object_unbind(obj);
+			ret = i915_gem_object_ggtt_unbind(obj);
 			if (ret)
 				goto unlock;
 		}

drivers/gpu/drm/i915/i915_drv.h

@@ -1737,7 +1737,8 @@ int __must_check i915_gem_object_pin(struct drm_i915_gem_object *obj,
 				     bool map_and_fenceable,
 				     bool nonblocking);
 void i915_gem_object_unpin(struct drm_i915_gem_object *obj);
-int __must_check i915_gem_object_unbind(struct drm_i915_gem_object *obj);
+int __must_check i915_vma_unbind(struct i915_vma *vma);
+int __must_check i915_gem_object_ggtt_unbind(struct drm_i915_gem_object *obj);
 int i915_gem_object_put_pages(struct drm_i915_gem_object *obj);
 void i915_gem_release_mmap(struct drm_i915_gem_object *obj);
 void i915_gem_lastclose(struct drm_device *dev);

drivers/gpu/drm/i915/i915_gem.c

@@ -38,7 +38,9 @@
 
 static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
 static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj);
-static __must_check int i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
+static __must_check int
+i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
+			   struct i915_address_space *vm,
 			   unsigned alignment,
 			   bool map_and_fenceable,
 			   bool nonblocking);
@@ -1692,7 +1694,6 @@ __i915_gem_shrink(struct drm_i915_private *dev_priv, long target,
 		  bool purgeable_only)
 {
 	struct drm_i915_gem_object *obj, *next;
-	struct i915_address_space *vm = &dev_priv->gtt.base;
 	long count = 0;
 
 	list_for_each_entry_safe(obj, next,
@@ -1706,13 +1707,16 @@ __i915_gem_shrink(struct drm_i915_private *dev_priv, long target,
 		}
 	}
 
-	list_for_each_entry_safe(obj, next, &vm->inactive_list, mm_list) {
+	list_for_each_entry_safe(obj, next, &dev_priv->mm.bound_list,
+				 global_list) {
+		struct i915_vma *vma, *v;
 
 		if (!i915_gem_object_is_purgeable(obj) && purgeable_only)
 			continue;
 
-		if (i915_gem_object_unbind(obj))
-			continue;
+		list_for_each_entry_safe(vma, v, &obj->vma_list, vma_link)
+			if (i915_vma_unbind(vma))
+				break;
 
 		if (!i915_gem_object_put_pages(obj)) {
 			count += obj->base.size >> PAGE_SHIFT;
@@ -2596,17 +2600,13 @@ static void i915_gem_object_finish_gtt(struct drm_i915_gem_object *obj)
 					    old_write_domain);
 }
 
-/**
- * Unbinds an object from the GTT aperture.
- */
-int
-i915_gem_object_unbind(struct drm_i915_gem_object *obj)
+int i915_vma_unbind(struct i915_vma *vma)
 {
+	struct drm_i915_gem_object *obj = vma->obj;
 	drm_i915_private_t *dev_priv = obj->base.dev->dev_private;
-	struct i915_vma *vma;
 	int ret;
 
-	if (!i915_gem_obj_ggtt_bound(obj))
+	if (list_empty(&vma->vma_link))
 		return 0;
 
 	if (obj->pin_count)
@@ -2629,7 +2629,7 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
 	if (ret)
 		return ret;
 
-	trace_i915_gem_object_unbind(obj);
+	trace_i915_vma_unbind(vma);
 
 	if (obj->has_global_gtt_mapping)
 		i915_gem_gtt_unbind_object(obj);
@@ -2644,7 +2644,6 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
 	/* Avoid an unnecessary call to unbind on rebind. */
 	obj->map_and_fenceable = true;
 
-	vma = i915_gem_obj_to_vma(obj, &dev_priv->gtt.base);
 	list_del(&vma->vma_link);
 	drm_mm_remove_node(&vma->node);
 	i915_gem_vma_destroy(vma);
@@ -2659,6 +2658,26 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
 	return 0;
 }
 
+/**
+ * Unbinds an object from the global GTT aperture.
+ */
+int
+i915_gem_object_ggtt_unbind(struct drm_i915_gem_object *obj)
+{
+	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
+	struct i915_address_space *ggtt = &dev_priv->gtt.base;
+
+	if (!i915_gem_obj_ggtt_bound(obj));
+		return 0;
+
+	if (obj->pin_count)
+		return -EBUSY;
+
+	BUG_ON(obj->pages == NULL);
+
+	return i915_vma_unbind(i915_gem_obj_to_vma(obj, ggtt));
+}
+
 int i915_gpu_idle(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
@@ -3076,18 +3095,18 @@ static void i915_gem_verify_gtt(struct drm_device *dev)
  * Finds free space in the GTT aperture and binds the object there.
  */
 static int
-i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
+i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
+			   struct i915_address_space *vm,
 			   unsigned alignment,
 			   bool map_and_fenceable,
 			   bool nonblocking)
 {
 	struct drm_device *dev = obj->base.dev;
 	drm_i915_private_t *dev_priv = dev->dev_private;
-	struct i915_address_space *vm = &dev_priv->gtt.base;
 	u32 size, fence_size, fence_alignment, unfenced_alignment;
 	bool mappable, fenceable;
-	size_t gtt_max = map_and_fenceable ?
-		dev_priv->gtt.mappable_end : dev_priv->gtt.base.total;
+	size_t gtt_max =
+		map_and_fenceable ? dev_priv->gtt.mappable_end : vm->total;
 	struct i915_vma *vma;
 	int ret;
 
@@ -3132,15 +3151,18 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 
 	i915_gem_object_pin_pages(obj);
 
-	vma = i915_gem_vma_create(obj, &dev_priv->gtt.base);
+	/* FIXME: For now we only ever use 1 VMA per object */
+	BUG_ON(!i915_is_ggtt(vm));
+	WARN_ON(!list_empty(&obj->vma_list));
+
+	vma = i915_gem_vma_create(obj, vm);
 	if (IS_ERR(vma)) {
 		ret = PTR_ERR(vma);
 		goto err_unpin;
 	}
 
 search_free:
-	ret = drm_mm_insert_node_in_range_generic(&dev_priv->gtt.base.mm,
-						  &vma->node,
+	ret = drm_mm_insert_node_in_range_generic(&vm->mm, &vma->node,
 						  size, alignment,
 						  obj->cache_level, 0, gtt_max);
 	if (ret) {
@@ -3165,18 +3187,25 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 
 	list_move_tail(&obj->global_list, &dev_priv->mm.bound_list);
 	list_add_tail(&obj->mm_list, &vm->inactive_list);
+
+	/* Keep GGTT vmas first to make debug easier */
+	if (i915_is_ggtt(vm))
 		list_add(&vma->vma_link, &obj->vma_list);
+	else
+		list_add_tail(&vma->vma_link, &obj->vma_list);
 
 	fenceable =
+		i915_is_ggtt(vm) &&
 		i915_gem_obj_ggtt_size(obj) == fence_size &&
 		(i915_gem_obj_ggtt_offset(obj) & (fence_alignment - 1)) == 0;
 
-	mappable = i915_gem_obj_ggtt_offset(obj) + obj->base.size <=
-		dev_priv->gtt.mappable_end;
+	mappable =
+		i915_is_ggtt(vm) &&
+		vma->node.start + obj->base.size <= dev_priv->gtt.mappable_end;
 
 	obj->map_and_fenceable = mappable && fenceable;
 
-	trace_i915_gem_object_bind(obj, map_and_fenceable);
+	trace_i915_vma_bind(vma, map_and_fenceable);
 	i915_gem_verify_gtt(dev);
 	return 0;
 
@@ -3345,7 +3374,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
 
 	list_for_each_entry(vma, &obj->vma_list, vma_link) {
 		if (!i915_gem_valid_gtt_space(dev, &vma->node, cache_level)) {
-			ret = i915_gem_object_unbind(obj);
+			ret = i915_vma_unbind(vma);
 			if (ret)
 				return ret;
 
@@ -3653,31 +3682,37 @@ i915_gem_object_pin(struct drm_i915_gem_object *obj,
 		    bool map_and_fenceable,
 		    bool nonblocking)
 {
+	struct i915_vma *vma;
 	int ret;
 
 	if (WARN_ON(obj->pin_count == DRM_I915_GEM_OBJECT_MAX_PIN_COUNT))
 		return -EBUSY;
 
-	if (i915_gem_obj_ggtt_bound(obj)) {
-		if ((alignment && i915_gem_obj_ggtt_offset(obj) & (alignment - 1)) ||
+	WARN_ON(map_and_fenceable && !i915_is_ggtt(vm));
+
+	vma = i915_gem_obj_to_vma(obj, vm);
+
+	if (vma) {
+		if ((alignment &&
+		     vma->node.start & (alignment - 1)) ||
 		    (map_and_fenceable && !obj->map_and_fenceable)) {
 			WARN(obj->pin_count,
 			     "bo is already pinned with incorrect alignment:"
 			     " offset=%lx, req.alignment=%x, req.map_and_fenceable=%d,"
 			     " obj->map_and_fenceable=%d\n",
-			     i915_gem_obj_ggtt_offset(obj), alignment,
+			     i915_gem_obj_offset(obj, vm), alignment,
 			     map_and_fenceable,
 			     obj->map_and_fenceable);
-			ret = i915_gem_object_unbind(obj);
+			ret = i915_vma_unbind(vma);
 			if (ret)
 				return ret;
 		}
 	}
 
-	if (!i915_gem_obj_ggtt_bound(obj)) {
+	if (!i915_gem_obj_bound(obj, vm)) {
 		struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
 
-		ret = i915_gem_object_bind_to_gtt(obj, alignment,
+		ret = i915_gem_object_bind_to_vm(obj, vm, alignment,
 						 map_and_fenceable,
 						 nonblocking);
 		if (ret)
@@ -3975,6 +4010,7 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 	struct drm_device *dev = obj->base.dev;
 	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct i915_vma *vma, *next;
 
 	trace_i915_gem_object_destroy(obj);
 
@@ -3982,16 +4018,22 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 		i915_gem_detach_phys_object(dev, obj);
 
 	obj->pin_count = 0;
-	if (WARN_ON(i915_gem_object_unbind(obj) == -ERESTARTSYS)) {
+	/* NB: 0 or 1 elements */
+	WARN_ON(!list_empty(&obj->vma_list) &&
+		!list_is_singular(&obj->vma_list));
+	list_for_each_entry_safe(vma, next, &obj->vma_list, vma_link) {
+		int ret = i915_vma_unbind(vma);
+		if (WARN_ON(ret == -ERESTARTSYS)) {
 			bool was_interruptible;
 
 			was_interruptible = dev_priv->mm.interruptible;
 			dev_priv->mm.interruptible = false;
 
-		WARN_ON(i915_gem_object_unbind(obj));
+			WARN_ON(i915_vma_unbind(vma));
 
 			dev_priv->mm.interruptible = was_interruptible;
 		}
+	}
 
 	/* Stolen objects don't hold a ref, but do hold pin count. Fix that up
 	 * before progressing. */

drivers/gpu/drm/i915/i915_gem_evict.c

@@ -147,7 +147,7 @@ i915_gem_evict_something(struct drm_device *dev, int min_size,
 				       struct drm_i915_gem_object,
 				       exec_list);
 		if (ret == 0)
-			ret = i915_gem_object_unbind(obj);
+			ret = i915_gem_object_ggtt_unbind(obj);
 
 		list_del_init(&obj->exec_list);
 		drm_gem_object_unreference(&obj->base);
@@ -185,7 +185,7 @@ i915_gem_evict_everything(struct drm_device *dev)
 	/* Having flushed everything, unbind() should never raise an error */
 	list_for_each_entry_safe(obj, next, &vm->inactive_list, mm_list)
 		if (obj->pin_count == 0)
-			WARN_ON(i915_gem_object_unbind(obj));
+			WARN_ON(i915_gem_object_ggtt_unbind(obj));
 
 	return 0;
 }

drivers/gpu/drm/i915/i915_gem_execbuffer.c

@@ -556,7 +556,7 @@ i915_gem_execbuffer_reserve(struct intel_ring_buffer *ring,
 			if ((entry->alignment &&
 			     obj_offset & (entry->alignment - 1)) ||
 			    (need_mappable && !obj->map_and_fenceable))
-				ret = i915_gem_object_unbind(obj);
+				ret = i915_vma_unbind(i915_gem_obj_to_vma(obj, vm));
 			else
 				ret = i915_gem_execbuffer_reserve_object(obj, ring, vm, need_relocs);
 			if (ret)

drivers/gpu/drm/i915/i915_gem_tiling.c

@@ -360,17 +360,18 @@ i915_gem_set_tiling(struct drm_device *dev, void *data,
 
 		obj->map_and_fenceable =
 			!i915_gem_obj_ggtt_bound(obj) ||
-			(i915_gem_obj_ggtt_offset(obj) + obj->base.size <= dev_priv->gtt.mappable_end &&
+			(i915_gem_obj_ggtt_offset(obj) +
+			 obj->base.size <= dev_priv->gtt.mappable_end &&
 			 i915_gem_object_fence_ok(obj, args->tiling_mode));
 
 		/* Rebind if we need a change of alignment */
 		if (!obj->map_and_fenceable) {
-			u32 unfenced_alignment =
+			u32 unfenced_align =
 				i915_gem_get_gtt_alignment(dev, obj->base.size,
 							    args->tiling_mode,
 							    false);
-			if (i915_gem_obj_ggtt_offset(obj) & (unfenced_alignment - 1))
-				ret = i915_gem_object_unbind(obj);
+			if (i915_gem_obj_ggtt_offset(obj) & (unfenced_align - 1))
+				ret = i915_gem_object_ggtt_unbind(obj);
 		}
 
 		if (ret == 0) {

drivers/gpu/drm/i915/i915_trace.h

@@ -33,47 +33,52 @@ TRACE_EVENT(i915_gem_object_create,
 	    TP_printk("obj=%p, size=%u", __entry->obj, __entry->size)
 );
 
-TRACE_EVENT(i915_gem_object_bind,
-	    TP_PROTO(struct drm_i915_gem_object *obj, bool mappable),
-	    TP_ARGS(obj, mappable),
+TRACE_EVENT(i915_vma_bind,
+	    TP_PROTO(struct i915_vma *vma, bool mappable),
+	    TP_ARGS(vma, mappable),
 
 	    TP_STRUCT__entry(
 			     __field(struct drm_i915_gem_object *, obj)
+			     __field(struct i915_address_space *, vm)
 			     __field(u32, offset)
 			     __field(u32, size)
 			     __field(bool, mappable)
 			     ),
 
 	    TP_fast_assign(
-			   __entry->obj = obj;
-			   __entry->offset = i915_gem_obj_ggtt_offset(obj);
-			   __entry->size = i915_gem_obj_ggtt_size(obj);
+			   __entry->obj = vma->obj;
+			   __entry->vm = vma->vm;
+			   __entry->offset = vma->node.start;
+			   __entry->size = vma->node.size;
 			   __entry->mappable = mappable;
 			   ),
 
-	    TP_printk("obj=%p, offset=%08x size=%x%s",
+	    TP_printk("obj=%p, offset=%08x size=%x%s vm=%p",
 		      __entry->obj, __entry->offset, __entry->size,
-		      __entry->mappable ? ", mappable" : "")
+		      __entry->mappable ? ", mappable" : "",
+		      __entry->vm)
 );
 
-TRACE_EVENT(i915_gem_object_unbind,
-	    TP_PROTO(struct drm_i915_gem_object *obj),
-	    TP_ARGS(obj),
+TRACE_EVENT(i915_vma_unbind,
+	    TP_PROTO(struct i915_vma *vma),
+	    TP_ARGS(vma),
 
 	    TP_STRUCT__entry(
 			     __field(struct drm_i915_gem_object *, obj)
+			     __field(struct i915_address_space *, vm)
 			     __field(u32, offset)
 			     __field(u32, size)
 			     ),
 
 	    TP_fast_assign(
-			   __entry->obj = obj;
-			   __entry->offset = i915_gem_obj_ggtt_offset(obj);
-			   __entry->size = i915_gem_obj_ggtt_size(obj);
+			   __entry->obj = vma->obj;
+			   __entry->vm = vma->vm;
+			   __entry->offset = vma->node.start;
+			   __entry->size = vma->node.size;
 			   ),
 
-	    TP_printk("obj=%p, offset=%08x size=%x",
-		      __entry->obj, __entry->offset, __entry->size)
+	    TP_printk("obj=%p, offset=%08x size=%x vm=%p",
+		      __entry->obj, __entry->offset, __entry->size, __entry->vm)
 );
 
 TRACE_EVENT(i915_gem_object_change_domain,