drm: Improve drm_mm search (and fix topdown allocation) with rbtrees

The drm_mm range manager claimed to support top-down insertion, but it
was neither searching for the top-most hole that could fit the
allocation request nor fitting the request to the hole correctly.

In order to search the range efficiently, we create a secondary index
for the holes using either their size or their address. This index
allows us to find the smallest hole or the hole at the bottom or top of
the range efficiently, whilst keeping the hole stack to rapidly service
evictions.

v2: Search for holes both high and low. Rename flags to mode.
v3: Discover rb_entry_safe() and use it!
v4: Kerneldoc for enum drm_mm_insert_mode.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Sinclair Yeh <syeh@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com> # vmwgfx
Reviewed-by: Lucas Stach <l.stach@pengutronix.de> #etnaviv
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170202210438.28702-1-chris@chris-wilson.co.uk

drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c

@@ -97,8 +97,7 @@ int amdgpu_gtt_mgr_alloc(struct ttm_mem_type_manager *man,
 {
 	struct amdgpu_gtt_mgr *mgr = man->priv;
 	struct drm_mm_node *node = mem->mm_node;
-	enum drm_mm_search_flags sflags = DRM_MM_SEARCH_BEST;
-	enum drm_mm_allocator_flags aflags = DRM_MM_CREATE_DEFAULT;
+	enum drm_mm_insert_mode mode;
 	unsigned long fpfn, lpfn;
 	int r;
 
@@ -115,15 +114,14 @@ int amdgpu_gtt_mgr_alloc(struct ttm_mem_type_manager *man,
 	else
 		lpfn = man->size;
 
-	if (place && place->flags & TTM_PL_FLAG_TOPDOWN) {
-		sflags = DRM_MM_SEARCH_BELOW;
-		aflags = DRM_MM_CREATE_TOP;
-	}
+	mode = DRM_MM_INSERT_BEST;
+	if (place && place->flags & TTM_PL_FLAG_TOPDOWN)
+		mode = DRM_MM_INSERT_HIGH;
 
 	spin_lock(&mgr->lock);
-	r = drm_mm_insert_node_in_range_generic(&mgr->mm, node, mem->num_pages,
-						mem->page_alignment, 0,
-						fpfn, lpfn, sflags, aflags);
+	r = drm_mm_insert_node_in_range(&mgr->mm, node,
+					mem->num_pages, mem->page_alignment, 0,
+					fpfn, lpfn, mode);
 	spin_unlock(&mgr->lock);
 
 	if (!r) {

drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c

@@ -97,8 +97,7 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
 	struct amdgpu_vram_mgr *mgr = man->priv;
 	struct drm_mm *mm = &mgr->mm;
 	struct drm_mm_node *nodes;
-	enum drm_mm_search_flags sflags = DRM_MM_SEARCH_DEFAULT;
-	enum drm_mm_allocator_flags aflags = DRM_MM_CREATE_DEFAULT;
+	enum drm_mm_insert_mode mode;
 	unsigned long lpfn, num_nodes, pages_per_node, pages_left;
 	unsigned i;
 	int r;
@@ -121,10 +120,9 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
 	if (!nodes)
 		return -ENOMEM;
 
-	if (place->flags & TTM_PL_FLAG_TOPDOWN) {
-		sflags = DRM_MM_SEARCH_BELOW;
-		aflags = DRM_MM_CREATE_TOP;
-	}
+	mode = DRM_MM_INSERT_BEST;
+	if (place->flags & TTM_PL_FLAG_TOPDOWN)
+		mode = DRM_MM_INSERT_HIGH;
 
 	pages_left = mem->num_pages;
 
@@ -135,13 +133,11 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
 
 		if (pages == pages_per_node)
 			alignment = pages_per_node;
-		else
-			sflags |= DRM_MM_SEARCH_BEST;
 
-		r = drm_mm_insert_node_in_range_generic(mm, &nodes[i], pages,
-							alignment, 0,
-							place->fpfn, lpfn,
-							sflags, aflags);
+		r = drm_mm_insert_node_in_range(mm, &nodes[i],
+						pages, alignment, 0,
+						place->fpfn, lpfn,
+						mode);
 		if (unlikely(r))
 			goto error;
 

drivers/gpu/drm/armada/armada_gem.c

@@ -148,8 +148,8 @@ armada_gem_linear_back(struct drm_device *dev, struct armada_gem_object *obj)
 			return -ENOSPC;
 
 		mutex_lock(&priv->linear_lock);
-		ret = drm_mm_insert_node(&priv->linear, node, size, align,
-					 DRM_MM_SEARCH_DEFAULT);
+		ret = drm_mm_insert_node_generic(&priv->linear, node,
+						 size, align, 0, 0);
 		mutex_unlock(&priv->linear_lock);
 		if (ret) {
 			kfree(node);

drivers/gpu/drm/drm_mm.c

@@ -97,14 +97,6 @@
  * locking would be fully redundant.
  */
 
-static struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm,
-						u64 size,
-						u64 alignment,
-						unsigned long color,
-						u64 start,
-						u64 end,
-						enum drm_mm_search_flags flags);
-
 #ifdef CONFIG_DRM_DEBUG_MM
 #include <linux/stackdepot.h>
 
@@ -226,69 +218,151 @@ static void drm_mm_interval_tree_add_node(struct drm_mm_node *hole_node,
 			    &drm_mm_interval_tree_augment);
 }
 
-static void drm_mm_insert_helper(struct drm_mm_node *hole_node,
-				 struct drm_mm_node *node,
-				 u64 size, u64 alignment,
-				 unsigned long color,
-				 u64 range_start, u64 range_end,
-				 enum drm_mm_allocator_flags flags)
+#define RB_INSERT(root, member, expr) do { \
+	struct rb_node **link = &root.rb_node, *rb = NULL; \
+	u64 x = expr(node); \
+	while (*link) { \
+		rb = *link; \
+		if (x < expr(rb_entry(rb, struct drm_mm_node, member))) \
+			link = &rb->rb_left; \
+		else \
+			link = &rb->rb_right; \
+	} \
+	rb_link_node(&node->member, rb, link); \
+	rb_insert_color(&node->member, &root); \
+} while (0)
+
+#define HOLE_SIZE(NODE) ((NODE)->hole_size)
+#define HOLE_ADDR(NODE) (__drm_mm_hole_node_start(NODE))
+
+static void add_hole(struct drm_mm_node *node)
 {
-	struct drm_mm *mm = hole_node->mm;
-	u64 hole_start = drm_mm_hole_node_start(hole_node);
-	u64 hole_end = drm_mm_hole_node_end(hole_node);
-	u64 adj_start = hole_start;
-	u64 adj_end = hole_end;
+	struct drm_mm *mm = node->mm;
 
-	DRM_MM_BUG_ON(!drm_mm_hole_follows(hole_node) || node->allocated);
+	node->hole_size =
+		__drm_mm_hole_node_end(node) - __drm_mm_hole_node_start(node);
+	DRM_MM_BUG_ON(!drm_mm_hole_follows(node));
 
-	if (mm->color_adjust)
-		mm->color_adjust(hole_node, color, &adj_start, &adj_end);
+	RB_INSERT(mm->holes_size, rb_hole_size, HOLE_SIZE);
+	RB_INSERT(mm->holes_addr, rb_hole_addr, HOLE_ADDR);
 
-	adj_start = max(adj_start, range_start);
-	adj_end = min(adj_end, range_end);
+	list_add(&node->hole_stack, &mm->hole_stack);
+}
 
-	if (flags & DRM_MM_CREATE_TOP)
-		adj_start = adj_end - size;
+static void rm_hole(struct drm_mm_node *node)
+{
+	DRM_MM_BUG_ON(!drm_mm_hole_follows(node));
 
-	if (alignment) {
-		u64 rem;
+	list_del(&node->hole_stack);
+	rb_erase(&node->rb_hole_size, &node->mm->holes_size);
+	rb_erase(&node->rb_hole_addr, &node->mm->holes_addr);
+	node->hole_size = 0;
 
-		div64_u64_rem(adj_start, alignment, &rem);
-		if (rem) {
-			if (flags & DRM_MM_CREATE_TOP)
-				adj_start -= rem;
-			else
-				adj_start += alignment - rem;
+	DRM_MM_BUG_ON(drm_mm_hole_follows(node));
+}
+
+static inline struct drm_mm_node *rb_hole_size_to_node(struct rb_node *rb)
+{
+	return rb_entry_safe(rb, struct drm_mm_node, rb_hole_size);
+}
+
+static inline struct drm_mm_node *rb_hole_addr_to_node(struct rb_node *rb)
+{
+	return rb_entry_safe(rb, struct drm_mm_node, rb_hole_addr);
+}
+
+static inline u64 rb_hole_size(struct rb_node *rb)
+{
+	return rb_entry(rb, struct drm_mm_node, rb_hole_size)->hole_size;
+}
+
+static struct drm_mm_node *best_hole(struct drm_mm *mm, u64 size)
+{
+	struct rb_node *best = NULL;
+	struct rb_node **link = &mm->holes_size.rb_node;
+
+	while (*link) {
+		struct rb_node *rb = *link;
+
+		if (size <= rb_hole_size(rb)) {
+			link = &rb->rb_left;
+			best = rb;
+		} else {
+			link = &rb->rb_right;
 		}
 	}
 
-	if (adj_start == hole_start) {
-		hole_node->hole_follows = 0;
-		list_del(&hole_node->hole_stack);
+	return rb_hole_size_to_node(best);
+}
+
+static struct drm_mm_node *find_hole(struct drm_mm *mm, u64 addr)
+{
+	struct drm_mm_node *node = NULL;
+	struct rb_node **link = &mm->holes_addr.rb_node;
+
+	while (*link) {
+		u64 hole_start;
+
+		node = rb_hole_addr_to_node(*link);
+		hole_start = __drm_mm_hole_node_start(node);
+
+		if (addr < hole_start)
+			link = &node->rb_hole_addr.rb_left;
+		else if (addr > hole_start + node->hole_size)
+			link = &node->rb_hole_addr.rb_right;
+		else
+			break;
 	}
 
-	node->start = adj_start;
-	node->size = size;
-	node->mm = mm;
-	node->color = color;
-	node->allocated = 1;
+	return node;
+}
 
-	list_add(&node->node_list, &hole_node->node_list);
+static struct drm_mm_node *
+first_hole(struct drm_mm *mm,
+	   u64 start, u64 end, u64 size,
+	   enum drm_mm_insert_mode mode)
+{
+	if (RB_EMPTY_ROOT(&mm->holes_size))
+		return NULL;
 
-	drm_mm_interval_tree_add_node(hole_node, node);
+	switch (mode) {
+	default:
+	case DRM_MM_INSERT_BEST:
+		return best_hole(mm, size);
 
-	DRM_MM_BUG_ON(node->start < range_start);
-	DRM_MM_BUG_ON(node->start < adj_start);
-	DRM_MM_BUG_ON(node->start + node->size > adj_end);
-	DRM_MM_BUG_ON(node->start + node->size > range_end);
+	case DRM_MM_INSERT_LOW:
+		return find_hole(mm, start);
 
-	node->hole_follows = 0;
-	if (__drm_mm_hole_node_start(node) < hole_end) {
-		list_add(&node->hole_stack, &mm->hole_stack);
-		node->hole_follows = 1;
+	case DRM_MM_INSERT_HIGH:
+		return find_hole(mm, end);
+
+	case DRM_MM_INSERT_EVICT:
+		return list_first_entry_or_null(&mm->hole_stack,
+						struct drm_mm_node,
+						hole_stack);
 	}
+}
 
-	save_stack(node);
+static struct drm_mm_node *
+next_hole(struct drm_mm *mm,
+	  struct drm_mm_node *node,
+	  enum drm_mm_insert_mode mode)
+{
+	switch (mode) {
+	default:
+	case DRM_MM_INSERT_BEST:
+		return rb_hole_size_to_node(rb_next(&node->rb_hole_size));
+
+	case DRM_MM_INSERT_LOW:
+		return rb_hole_addr_to_node(rb_next(&node->rb_hole_addr));
+
+	case DRM_MM_INSERT_HIGH:
+		return rb_hole_addr_to_node(rb_prev(&node->rb_hole_addr));
+
+	case DRM_MM_INSERT_EVICT:
+		node = list_next_entry(node, hole_stack);
+		return &node->hole_stack == &mm->hole_stack ? NULL : node;
+	}
 }
 
 /**
@@ -317,21 +391,12 @@ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node)
 		return -ENOSPC;
 
 	/* Find the relevant hole to add our node to */
-	hole = drm_mm_interval_tree_iter_first(&mm->interval_tree,
-					       node->start, ~(u64)0);
-	if (hole) {
-		if (hole->start < end)
-			return -ENOSPC;
-	} else {
-		hole = list_entry(drm_mm_nodes(mm), typeof(*hole), node_list);
-	}
-
-	hole = list_last_entry(&hole->node_list, typeof(*hole), node_list);
-	if (!drm_mm_hole_follows(hole))
+	hole = find_hole(mm, node->start);
+	if (!hole)
 		return -ENOSPC;
 
 	adj_start = hole_start = __drm_mm_hole_node_start(hole);
-	adj_end = hole_end = __drm_mm_hole_node_end(hole);
+	adj_end = hole_end = hole_start + hole->hole_size;
 
 	if (mm->color_adjust)
 		mm->color_adjust(hole, node->color, &adj_start, &adj_end);
@@ -340,70 +405,130 @@ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node)
 		return -ENOSPC;
 
 	node->mm = mm;
-	node->allocated = 1;
 
 	list_add(&node->node_list, &hole->node_list);
-
 	drm_mm_interval_tree_add_node(hole, node);
+	node->allocated = true;
+	node->hole_size = 0;
 
-	if (node->start == hole_start) {
-		hole->hole_follows = 0;
-		list_del(&hole->hole_stack);
-	}
-
-	node->hole_follows = 0;
-	if (end != hole_end) {
-		list_add(&node->hole_stack, &mm->hole_stack);
-		node->hole_follows = 1;
-	}
+	rm_hole(hole);
+	if (node->start > hole_start)
+		add_hole(hole);
+	if (end < hole_end)
+		add_hole(node);
 
 	save_stack(node);
-
 	return 0;
 }
 EXPORT_SYMBOL(drm_mm_reserve_node);
 
 /**
- * drm_mm_insert_node_in_range_generic - ranged search for space and insert @node
+ * drm_mm_insert_node_in_range - ranged search for space and insert @node
  * @mm: drm_mm to allocate from
  * @node: preallocate node to insert
  * @size: size of the allocation
  * @alignment: alignment of the allocation
  * @color: opaque tag value to use for this node
- * @start: start of the allowed range for this node
- * @end: end of the allowed range for this node
- * @sflags: flags to fine-tune the allocation search
- * @aflags: flags to fine-tune the allocation behavior
+ * @range_start: start of the allowed range for this node
+ * @range_end: end of the allowed range for this node
+ * @mode: fine-tune the allocation search and placement
  *
  * The preallocated @node must be cleared to 0.
  *
  * Returns:
  * 0 on success, -ENOSPC if there's no suitable hole.
  */
-int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, struct drm_mm_node *node,
-					u64 size, u64 alignment,
-					unsigned long color,
-					u64 start, u64 end,
-					enum drm_mm_search_flags sflags,
-					enum drm_mm_allocator_flags aflags)
+int drm_mm_insert_node_in_range(struct drm_mm * const mm,
+				struct drm_mm_node * const node,
+				u64 size, u64 alignment,
+				unsigned long color,
+				u64 range_start, u64 range_end,
+				enum drm_mm_insert_mode mode)
 {
-	struct drm_mm_node *hole_node;
+	struct drm_mm_node *hole;
+	u64 remainder_mask;
 
-	if (WARN_ON(size == 0))
-		return -EINVAL;
+	DRM_MM_BUG_ON(range_start >= range_end);
 
-	hole_node = drm_mm_search_free_in_range_generic(mm,
-							size, alignment, color,
-							start, end, sflags);
-	if (!hole_node)
+	if (unlikely(size == 0 || range_end - range_start < size))
 		return -ENOSPC;
 
-	drm_mm_insert_helper(hole_node, node,
-			     size, alignment, color,
-			     start, end, aflags);
-	return 0;
+	if (alignment <= 1)
+		alignment = 0;
+
+	remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0;
+	for (hole = first_hole(mm, range_start, range_end, size, mode); hole;
+	     hole = next_hole(mm, hole, mode)) {
+		u64 hole_start = __drm_mm_hole_node_start(hole);
+		u64 hole_end = hole_start + hole->hole_size;
+		u64 adj_start, adj_end;
+		u64 col_start, col_end;
+
+		if (mode == DRM_MM_INSERT_LOW && hole_start >= range_end)
+			break;
+
+		if (mode == DRM_MM_INSERT_HIGH && hole_end <= range_start)
+			break;
+
+		col_start = hole_start;
+		col_end = hole_end;
+		if (mm->color_adjust)
+			mm->color_adjust(hole, color, &col_start, &col_end);
+
+		adj_start = max(col_start, range_start);
+		adj_end = min(col_end, range_end);
+
+		if (adj_end <= adj_start || adj_end - adj_start < size)
+			continue;
+
+		if (mode == DRM_MM_INSERT_HIGH)
+			adj_start = adj_end - size;
+
+		if (alignment) {
+			u64 rem;
+
+			if (likely(remainder_mask))
+				rem = adj_start & remainder_mask;
+			else
+				div64_u64_rem(adj_start, alignment, &rem);
+			if (rem) {
+				adj_start -= rem;
+				if (mode != DRM_MM_INSERT_HIGH)
+					adj_start += alignment;
+
+				if (adj_start < max(col_start, range_start) ||
+				    min(col_end, range_end) - adj_start < size)
+					continue;
+
+				if (adj_end <= adj_start ||
+				    adj_end - adj_start < size)
+					continue;
+			}
+		}
+
+		node->mm = mm;
+		node->size = size;
+		node->start = adj_start;
+		node->color = color;
+		node->hole_size = 0;
+
+		list_add(&node->node_list, &hole->node_list);
+		drm_mm_interval_tree_add_node(hole, node);
+		node->allocated = true;
+
+		rm_hole(hole);
+		if (adj_start > hole_start)
+			add_hole(hole);
+		if (adj_start + size < hole_end)
+			add_hole(node);
+
+		save_stack(node);
+		return 0;
+	}
+
+	return -ENOSPC;
 }
-EXPORT_SYMBOL(drm_mm_insert_node_in_range_generic);
+EXPORT_SYMBOL(drm_mm_insert_node_in_range);
 
 /**
  * drm_mm_remove_node - Remove a memory node from the allocator.
@@ -421,92 +546,20 @@ void drm_mm_remove_node(struct drm_mm_node *node)
 	DRM_MM_BUG_ON(!node->allocated);
 	DRM_MM_BUG_ON(node->scanned_block);
 
-	prev_node =
-	    list_entry(node->node_list.prev, struct drm_mm_node, node_list);
-
-	if (drm_mm_hole_follows(node)) {
-		DRM_MM_BUG_ON(__drm_mm_hole_node_start(node) ==
-			      __drm_mm_hole_node_end(node));
-		list_del(&node->hole_stack);
-	} else {
-		DRM_MM_BUG_ON(__drm_mm_hole_node_start(node) !=
-			      __drm_mm_hole_node_end(node));
-	}
+	prev_node = list_prev_entry(node, node_list);
 
-	if (!drm_mm_hole_follows(prev_node)) {
-		prev_node->hole_follows = 1;
-		list_add(&prev_node->hole_stack, &mm->hole_stack);
-	} else
-		list_move(&prev_node->hole_stack, &mm->hole_stack);
+	if (drm_mm_hole_follows(node))
+		rm_hole(node);
 
 	drm_mm_interval_tree_remove(node, &mm->interval_tree);
 	list_del(&node->node_list);
-	node->allocated = 0;
-}
-EXPORT_SYMBOL(drm_mm_remove_node);
-
-static int check_free_hole(u64 start, u64 end, u64 size, u64 alignment)
-{
-	if (end - start < size)
-		return 0;
-
-	if (alignment) {
-		u64 rem;
-
-		div64_u64_rem(start, alignment, &rem);
-		if (rem)
-			start += alignment - rem;
-	}
+	node->allocated = false;
 
-	return end >= start + size;
-}
-
-static struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm,
-							u64 size,
-							u64 alignment,
-							unsigned long color,
-							u64 start,
-							u64 end,
-							enum drm_mm_search_flags flags)
-{
-	struct drm_mm_node *entry;
-	struct drm_mm_node *best;
-	u64 adj_start;
-	u64 adj_end;
-	u64 best_size;
-
-	DRM_MM_BUG_ON(mm->scan_active);
-
-	best = NULL;
-	best_size = ~0UL;
-
-	__drm_mm_for_each_hole(entry, mm, adj_start, adj_end,
-			       flags & DRM_MM_SEARCH_BELOW) {
-		u64 hole_size = adj_end - adj_start;
-
-		if (mm->color_adjust) {
-			mm->color_adjust(entry, color, &adj_start, &adj_end);
-			if (adj_end <= adj_start)
-				continue;
-		}
-
-		adj_start = max(adj_start, start);
-		adj_end = min(adj_end, end);
-
-		if (!check_free_hole(adj_start, adj_end, size, alignment))
-			continue;
-
-		if (!(flags & DRM_MM_SEARCH_BEST))
-			return entry;
-
-		if (hole_size < best_size) {
-			best = entry;
-			best_size = hole_size;
-		}
-	}
-
-	return best;
+	if (drm_mm_hole_follows(prev_node))
+		rm_hole(prev_node);
+	add_hole(prev_node);
 }
+EXPORT_SYMBOL(drm_mm_remove_node);
 
 /**
  * drm_mm_replace_node - move an allocation from @old to @new
@@ -521,18 +574,23 @@ void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new)
 {
 	DRM_MM_BUG_ON(!old->allocated);
 
+	*new = *old;
+
 	list_replace(&old->node_list, &new->node_list);
-	list_replace(&old->hole_stack, &new->hole_stack);
 	rb_replace_node(&old->rb, &new->rb, &old->mm->interval_tree);
-	new->hole_follows = old->hole_follows;
-	new->mm = old->mm;
-	new->start = old->start;
-	new->size = old->size;
-	new->color = old->color;
-	new->__subtree_last = old->__subtree_last;
-
-	old->allocated = 0;
-	new->allocated = 1;
+
+	if (drm_mm_hole_follows(old)) {
+		list_replace(&old->hole_stack, &new->hole_stack);
+		rb_replace_node(&old->rb_hole_size,
+				&new->rb_hole_size,
+				&old->mm->holes_size);
+		rb_replace_node(&old->rb_hole_addr,
+				&new->rb_hole_addr,
+				&old->mm->holes_addr);
+	}
+
+	old->allocated = false;
+	new->allocated = true;
 }
 EXPORT_SYMBOL(drm_mm_replace_node);
 
@@ -577,7 +635,7 @@ EXPORT_SYMBOL(drm_mm_replace_node);
  * @color: opaque tag value to use for the allocation
  * @start: start of the allowed range for the allocation
  * @end: end of the allowed range for the allocation
- * @flags: flags to specify how the allocation will be performed afterwards
+ * @mode: fine-tune the allocation search and placement
  *
  * This simply sets up the scanning routines with the parameters for the desired
  * hole.
@@ -593,7 +651,7 @@ void drm_mm_scan_init_with_range(struct drm_mm_scan *scan,
 				 unsigned long color,
 				 u64 start,
 				 u64 end,
-				 unsigned int flags)
+				 enum drm_mm_insert_mode mode)
 {
 	DRM_MM_BUG_ON(start >= end);
 	DRM_MM_BUG_ON(!size || size > end - start);
@@ -608,7 +666,7 @@ void drm_mm_scan_init_with_range(struct drm_mm_scan *scan,
 	scan->alignment = alignment;
 	scan->remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0;
 	scan->size = size;
-	scan->flags = flags;
+	scan->mode = mode;
 
 	DRM_MM_BUG_ON(end <= start);
 	scan->range_start = start;
@@ -667,7 +725,7 @@ bool drm_mm_scan_add_block(struct drm_mm_scan *scan,
 	if (adj_end <= adj_start || adj_end - adj_start < scan->size)
 		return false;
 
-	if (scan->flags == DRM_MM_CREATE_TOP)
+	if (scan->mode == DRM_MM_INSERT_HIGH)
 		adj_start = adj_end - scan->size;
 
 	if (scan->alignment) {
@@ -679,7 +737,7 @@ bool drm_mm_scan_add_block(struct drm_mm_scan *scan,
 			div64_u64_rem(adj_start, scan->alignment, &rem);
 		if (rem) {
 			adj_start -= rem;
-			if (scan->flags != DRM_MM_CREATE_TOP)
+			if (scan->mode != DRM_MM_INSERT_HIGH)
 				adj_start += scan->alignment;
 			if (adj_start < max(col_start, scan->range_start) ||
 			    min(col_end, scan->range_end) - adj_start < scan->size)
@@ -775,7 +833,7 @@ struct drm_mm_node *drm_mm_scan_color_evict(struct drm_mm_scan *scan)
 
 	hole = list_first_entry(&mm->hole_stack, typeof(*hole), hole_stack);
 	hole_start = __drm_mm_hole_node_start(hole);
-	hole_end = __drm_mm_hole_node_end(hole);
+	hole_end = hole_start + hole->hole_size;
 
 	DRM_MM_BUG_ON(hole_start > scan->hit_start);
 	DRM_MM_BUG_ON(hole_end < scan->hit_end);
@@ -802,21 +860,22 @@ void drm_mm_init(struct drm_mm *mm, u64 start, u64 size)
 {
 	DRM_MM_BUG_ON(start + size <= start);
 
+	mm->color_adjust = NULL;
+
 	INIT_LIST_HEAD(&mm->hole_stack);
-	mm->scan_active = 0;
+	mm->interval_tree = RB_ROOT;
+	mm->holes_size = RB_ROOT;
+	mm->holes_addr = RB_ROOT;
 
 	/* Clever trick to avoid a special case in the free hole tracking. */
 	INIT_LIST_HEAD(&mm->head_node.node_list);
-	mm->head_node.allocated = 0;
-	mm->head_node.hole_follows = 1;
+	mm->head_node.allocated = false;
 	mm->head_node.mm = mm;
 	mm->head_node.start = start + size;
-	mm->head_node.size = start - mm->head_node.start;
-	list_add_tail(&mm->head_node.hole_stack, &mm->hole_stack);
+	mm->head_node.size = -size;
+	add_hole(&mm->head_node);
 
-	mm->interval_tree = RB_ROOT;
-
-	mm->color_adjust = NULL;
+	mm->scan_active = 0;
 }
 EXPORT_SYMBOL(drm_mm_init);
 
@@ -837,20 +896,17 @@ EXPORT_SYMBOL(drm_mm_takedown);
 
 static u64 drm_mm_dump_hole(struct drm_printer *p, const struct drm_mm_node *entry)
 {
-	u64 hole_start, hole_end, hole_size;
-
-	if (entry->hole_follows) {
-		hole_start = drm_mm_hole_node_start(entry);
-		hole_end = drm_mm_hole_node_end(entry);
-		hole_size = hole_end - hole_start;
-		drm_printf(p, "%#018llx-%#018llx: %llu: free\n", hole_start,
-			   hole_end, hole_size);
-		return hole_size;
+	u64 start, size;
+
+	size = entry->hole_size;
+	if (size) {
+		start = drm_mm_hole_node_start(entry);
+		drm_printf(p, "%#018llx-%#018llx: %llu: free\n",
+			   start, start + size, size);
 	}
 
-	return 0;
+	return size;
 }
-
 /**
  * drm_mm_print - print allocator state
  * @mm: drm_mm allocator to print

drivers/gpu/drm/drm_vma_manager.c

@@ -212,8 +212,7 @@ int drm_vma_offset_add(struct drm_vma_offset_manager *mgr,
 		goto out_unlock;
 	}
 
-	ret = drm_mm_insert_node(&mgr->vm_addr_space_mm, &node->vm_node,
-				 pages, 0, DRM_MM_SEARCH_DEFAULT);
+	ret = drm_mm_insert_node(&mgr->vm_addr_space_mm, &node->vm_node, pages);
 	if (ret)
 		goto out_unlock;
 

drivers/gpu/drm/etnaviv/etnaviv_mmu.c

@@ -108,6 +108,7 @@ static int etnaviv_iommu_find_iova(struct etnaviv_iommu *mmu,
 				   struct drm_mm_node *node, size_t size)
 {
 	struct etnaviv_vram_mapping *free = NULL;
+	enum drm_mm_insert_mode mode = DRM_MM_INSERT_LOW;
 	int ret;
 
 	lockdep_assert_held(&mmu->lock);
@@ -119,9 +120,9 @@ static int etnaviv_iommu_find_iova(struct etnaviv_iommu *mmu,
 		bool found;
 
 		ret = drm_mm_insert_node_in_range(&mmu->mm, node,
-			size, 0, mmu->last_iova, ~0UL,
-			DRM_MM_SEARCH_DEFAULT);
-
+						  size, 0, 0,
+						  mmu->last_iova, U64_MAX,
+						  mode);
 		if (ret != -ENOSPC)
 			break;
 
@@ -136,7 +137,7 @@ static int etnaviv_iommu_find_iova(struct etnaviv_iommu *mmu,
 		}
 
 		/* Try to retire some entries */
-		drm_mm_scan_init(&scan, &mmu->mm, size, 0, 0, 0);
+		drm_mm_scan_init(&scan, &mmu->mm, size, 0, 0, mode);
 
 		found = 0;
 		INIT_LIST_HEAD(&list);
@@ -188,6 +189,8 @@ static int etnaviv_iommu_find_iova(struct etnaviv_iommu *mmu,
 			list_del_init(&m->scan_node);
 		}
 
+		mode = DRM_MM_INSERT_EVICT;
+
 		/*
 		 * We removed enough mappings so that the new allocation will
 		 * succeed, retry the allocation one more time.

drivers/gpu/drm/i915/i915_gem.c

@@ -69,12 +69,10 @@ insert_mappable_node(struct i915_ggtt *ggtt,
                      struct drm_mm_node *node, u32 size)
 {
 	memset(node, 0, sizeof(*node));
-	return drm_mm_insert_node_in_range_generic(&ggtt->base.mm, node,
-						   size, 0,
-						   I915_COLOR_UNEVICTABLE,
-						   0, ggtt->mappable_end,
-						   DRM_MM_SEARCH_DEFAULT,
-						   DRM_MM_CREATE_DEFAULT);
+	return drm_mm_insert_node_in_range(&ggtt->base.mm, node,
+					   size, 0, I915_COLOR_UNEVICTABLE,
+					   0, ggtt->mappable_end,
+					   DRM_MM_INSERT_LOW);
 }
 
 static void

drivers/gpu/drm/i915/i915_gem_evict.c

@@ -109,6 +109,7 @@ i915_gem_evict_something(struct i915_address_space *vm,
 	}, **phase;
 	struct i915_vma *vma, *next;
 	struct drm_mm_node *node;
+	enum drm_mm_insert_mode mode;
 	int ret;
 
 	lockdep_assert_held(&vm->i915->drm.struct_mutex);
@@ -127,10 +128,14 @@ i915_gem_evict_something(struct i915_address_space *vm,
 	 * On each list, the oldest objects lie at the HEAD with the freshest
 	 * object on the TAIL.
 	 */
+	mode = DRM_MM_INSERT_BEST;
+	if (flags & PIN_HIGH)
+		mode = DRM_MM_INSERT_HIGH;
+	if (flags & PIN_MAPPABLE)
+		mode = DRM_MM_INSERT_LOW;
 	drm_mm_scan_init_with_range(&scan, &vm->mm,
 				    min_size, alignment, cache_level,
-				    start, end,
-				    flags & PIN_HIGH ? DRM_MM_CREATE_TOP : 0);
+				    start, end, mode);
 
 	/* Retire before we search the active list. Although we have
 	 * reasonable accuracy in our retirement lists, we may have

drivers/gpu/drm/i915/i915_gem_execbuffer.c

@@ -436,12 +436,11 @@ static void *reloc_iomap(struct drm_i915_gem_object *obj,
 					       PIN_MAPPABLE | PIN_NONBLOCK);
 		if (IS_ERR(vma)) {
 			memset(&cache->node, 0, sizeof(cache->node));
-			ret = drm_mm_insert_node_in_range_generic
+			ret = drm_mm_insert_node_in_range
 				(&ggtt->base.mm, &cache->node,
 				 PAGE_SIZE, 0, I915_COLOR_UNEVICTABLE,
 				 0, ggtt->mappable_end,
-				 DRM_MM_SEARCH_DEFAULT,
-				 DRM_MM_CREATE_DEFAULT);
+				 DRM_MM_INSERT_LOW);
 			if (ret) /* no inactive aperture space, use cpu reloc */
 				return NULL;
 		} else {

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -2748,12 +2748,10 @@ int i915_gem_init_ggtt(struct drm_i915_private *dev_priv)
 		return ret;
 
 	/* Reserve a mappable slot for our lockless error capture */
-	ret = drm_mm_insert_node_in_range_generic(&ggtt->base.mm,
-						  &ggtt->error_capture,
-						  PAGE_SIZE, 0,
-						  I915_COLOR_UNEVICTABLE,
-						  0, ggtt->mappable_end,
-						  0, 0);
+	ret = drm_mm_insert_node_in_range(&ggtt->base.mm, &ggtt->error_capture,
+					  PAGE_SIZE, 0, I915_COLOR_UNEVICTABLE,
+					  0, ggtt->mappable_end,
+					  DRM_MM_INSERT_LOW);
 	if (ret)
 		return ret;
 
@@ -3663,7 +3661,7 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,
 			u64 size, u64 alignment, unsigned long color,
 			u64 start, u64 end, unsigned int flags)
 {
-	u32 search_flag, alloc_flag;
+	enum drm_mm_insert_mode mode;
 	u64 offset;
 	int err;
 
@@ -3684,13 +3682,11 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,
 	if (unlikely(round_up(start, alignment) > round_down(end - size, alignment)))
 		return -ENOSPC;
 
-	if (flags & PIN_HIGH) {
-		search_flag = DRM_MM_SEARCH_BELOW;
-		alloc_flag = DRM_MM_CREATE_TOP;
-	} else {
-		search_flag = DRM_MM_SEARCH_DEFAULT;
-		alloc_flag = DRM_MM_CREATE_DEFAULT;
-	}
+	mode = DRM_MM_INSERT_BEST;
+	if (flags & PIN_HIGH)
+		mode = DRM_MM_INSERT_HIGH;
+	if (flags & PIN_MAPPABLE)
+		mode = DRM_MM_INSERT_LOW;
 
 	/* We only allocate in PAGE_SIZE/GTT_PAGE_SIZE (4096) chunks,
 	 * so we know that we always have a minimum alignment of 4096.
@@ -3702,10 +3698,9 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,
 	if (alignment <= I915_GTT_MIN_ALIGNMENT)
 		alignment = 0;
 
-	err = drm_mm_insert_node_in_range_generic(&vm->mm, node,
-						  size, alignment, color,
-						  start, end,
-						  search_flag, alloc_flag);
+	err = drm_mm_insert_node_in_range(&vm->mm, node,
+					  size, alignment, color,
+					  start, end, mode);
 	if (err != -ENOSPC)
 		return err;
 
@@ -3743,9 +3738,7 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,
 	if (err)
 		return err;
 
-	search_flag = DRM_MM_SEARCH_DEFAULT;
-	return drm_mm_insert_node_in_range_generic(&vm->mm, node,
-						   size, alignment, color,
-						   start, end,
-						   search_flag, alloc_flag);
+	return drm_mm_insert_node_in_range(&vm->mm, node,
+					   size, alignment, color,
+					   start, end, DRM_MM_INSERT_EVICT);
 }

drivers/gpu/drm/i915/i915_gem_stolen.c

@@ -55,9 +55,9 @@ int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv,
 		return -ENODEV;
 
 	mutex_lock(&dev_priv->mm.stolen_lock);
-	ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node, size,
-					  alignment, start, end,
-					  DRM_MM_SEARCH_DEFAULT);
+	ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node,
+					  size, alignment, 0,
+					  start, end, DRM_MM_INSERT_BEST);
 	mutex_unlock(&dev_priv->mm.stolen_lock);
 
 	return ret;

drivers/gpu/drm/msm/msm_gem.c

@@ -54,8 +54,7 @@ static struct page **get_pages_vram(struct drm_gem_object *obj,
 	if (!p)
 		return ERR_PTR(-ENOMEM);
 
-	ret = drm_mm_insert_node(&priv->vram.mm, msm_obj->vram_node,
-			npages, 0, DRM_MM_SEARCH_DEFAULT);
+	ret = drm_mm_insert_node(&priv->vram.mm, msm_obj->vram_node, npages);
 	if (ret) {
 		drm_free_large(p);
 		return ERR_PTR(ret);

drivers/gpu/drm/msm/msm_gem_vma.c

@@ -45,8 +45,7 @@ msm_gem_map_vma(struct msm_gem_address_space *aspace,
 	if (WARN_ON(drm_mm_node_allocated(&vma->node)))
 		return 0;
 
-	ret = drm_mm_insert_node(&aspace->mm, &vma->node, npages,
-			0, DRM_MM_SEARCH_DEFAULT);
+	ret = drm_mm_insert_node(&aspace->mm, &vma->node, npages);
 	if (ret)
 		return ret;
 

drivers/gpu/drm/selftests/test-drm_mm.c

@@ -22,23 +22,24 @@ static unsigned int max_iterations = 8192;
 static unsigned int max_prime = 128;
 
 enum {
-	DEFAULT,
-	TOPDOWN,
 	BEST,
+	BOTTOMUP,
+	TOPDOWN,
+	EVICT,
 };
 
 static const struct insert_mode {
 	const char *name;
-	unsigned int search_flags;
-	unsigned int create_flags;
+	enum drm_mm_insert_mode mode;
 } insert_modes[] = {
-	[DEFAULT] = { "default", DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT },
-	[TOPDOWN] = { "top-down", DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP },
-	[BEST] = { "best", DRM_MM_SEARCH_BEST, DRM_MM_CREATE_DEFAULT },
+	[BEST] = { "best", DRM_MM_INSERT_BEST },
+	[BOTTOMUP] = { "bottom-up", DRM_MM_INSERT_LOW },
+	[TOPDOWN] = { "top-down", DRM_MM_INSERT_HIGH },
+	[EVICT] = { "evict", DRM_MM_INSERT_EVICT },
 	{}
 }, evict_modes[] = {
-	{ "default", DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT },
-	{ "top-down", DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP },
+	{ "bottom-up", DRM_MM_INSERT_LOW },
+	{ "top-down", DRM_MM_INSERT_HIGH },
 	{}
 };
 
@@ -526,8 +527,7 @@ static bool expect_insert(struct drm_mm *mm, struct drm_mm_node *node,
 
 	err = drm_mm_insert_node_generic(mm, node,
 					 size, alignment, color,
-					 mode->search_flags,
-					 mode->create_flags);
+					 mode->mode);
 	if (err) {
 		pr_err("insert (size=%llu, alignment=%llu, color=%lu, mode=%s) failed with err=%d\n",
 		       size, alignment, color, mode->name, err);
@@ -547,7 +547,7 @@ static bool expect_insert_fail(struct drm_mm *mm, u64 size)
 	struct drm_mm_node tmp = {};
 	int err;
 
-	err = drm_mm_insert_node(mm, &tmp, size, 0, DRM_MM_SEARCH_DEFAULT);
+	err = drm_mm_insert_node(mm, &tmp, size);
 	if (likely(err == -ENOSPC))
 		return true;
 
@@ -753,11 +753,10 @@ static bool expect_insert_in_range(struct drm_mm *mm, struct drm_mm_node *node,
 {
 	int err;
 
-	err = drm_mm_insert_node_in_range_generic(mm, node,
-						  size, alignment, color,
-						  range_start, range_end,
-						  mode->search_flags,
-						  mode->create_flags);
+	err = drm_mm_insert_node_in_range(mm, node,
+					  size, alignment, color,
+					  range_start, range_end,
+					  mode->mode);
 	if (err) {
 		pr_err("insert (size=%llu, alignment=%llu, color=%lu, mode=%s) nto range [%llx, %llx] failed with err=%d\n",
 		       size, alignment, color, mode->name,
@@ -781,11 +780,10 @@ static bool expect_insert_in_range_fail(struct drm_mm *mm,
 	struct drm_mm_node tmp = {};
 	int err;
 
-	err = drm_mm_insert_node_in_range_generic(mm, &tmp,
-						  size, 0, 0,
-						  range_start, range_end,
-						  DRM_MM_SEARCH_DEFAULT,
-						  DRM_MM_CREATE_DEFAULT);
+	err = drm_mm_insert_node_in_range(mm, &tmp,
+					  size, 0, 0,
+					  range_start, range_end,
+					  0);
 	if (likely(err == -ENOSPC))
 		return true;
 
@@ -1324,7 +1322,7 @@ static int evict_something(struct drm_mm *mm,
 	drm_mm_scan_init_with_range(&scan, mm,
 				    size, alignment, 0,
 				    range_start, range_end,
-				    mode->create_flags);
+				    mode->mode);
 	if (!evict_nodes(&scan,
 			 nodes, order, count, false,
 			 &evict_list))
@@ -1332,8 +1330,7 @@ static int evict_something(struct drm_mm *mm,
 
 	memset(&tmp, 0, sizeof(tmp));
 	err = drm_mm_insert_node_generic(mm, &tmp, size, alignment, 0,
-					 mode->search_flags,
-					 mode->create_flags);
+					 DRM_MM_INSERT_EVICT);
 	if (err) {
 		pr_err("Failed to insert into eviction hole: size=%d, align=%d\n",
 		       size, alignment);
@@ -1408,8 +1405,7 @@ static int igt_evict(void *ignored)
 	ret = -EINVAL;
 	drm_mm_init(&mm, 0, size);
 	for (n = 0; n < size; n++) {
-		err = drm_mm_insert_node(&mm, &nodes[n].node, 1, 0,
-					 DRM_MM_SEARCH_DEFAULT);
+		err = drm_mm_insert_node(&mm, &nodes[n].node, 1);
 		if (err) {
 			pr_err("insert failed, step %d\n", n);
 			ret = err;
@@ -1517,8 +1513,7 @@ static int igt_evict_range(void *ignored)
 	ret = -EINVAL;
 	drm_mm_init(&mm, 0, size);
 	for (n = 0; n < size; n++) {
-		err = drm_mm_insert_node(&mm, &nodes[n].node, 1, 0,
-					 DRM_MM_SEARCH_DEFAULT);
+		err = drm_mm_insert_node(&mm, &nodes[n].node, 1);
 		if (err) {
 			pr_err("insert failed, step %d\n", n);
 			ret = err;
@@ -1904,7 +1899,7 @@ static int evict_color(struct drm_mm *mm,
 	drm_mm_scan_init_with_range(&scan, mm,
 				    size, alignment, color,
 				    range_start, range_end,
-				    mode->create_flags);
+				    mode->mode);
 	if (!evict_nodes(&scan,
 			 nodes, order, count, true,
 			 &evict_list))
@@ -1912,8 +1907,7 @@ static int evict_color(struct drm_mm *mm,
 
 	memset(&tmp, 0, sizeof(tmp));
 	err = drm_mm_insert_node_generic(mm, &tmp, size, alignment, color,
-					 mode->search_flags,
-					 mode->create_flags);
+					 DRM_MM_INSERT_EVICT);
 	if (err) {
 		pr_err("Failed to insert into eviction hole: size=%d, align=%d, color=%lu, err=%d\n",
 		       size, alignment, color, err);

drivers/gpu/drm/sis/sis_mm.c

@@ -109,8 +109,7 @@ static int sis_drm_alloc(struct drm_device *dev, struct drm_file *file,
 	if (pool == AGP_TYPE) {
 		retval = drm_mm_insert_node(&dev_priv->agp_mm,
 					    &item->mm_node,
-					    mem->size, 0,
-					    DRM_MM_SEARCH_DEFAULT);
+					    mem->size);
 		offset = item->mm_node.start;
 	} else {
 #if defined(CONFIG_FB_SIS) || defined(CONFIG_FB_SIS_MODULE)
@@ -122,8 +121,7 @@ static int sis_drm_alloc(struct drm_device *dev, struct drm_file *file,
 #else
 		retval = drm_mm_insert_node(&dev_priv->vram_mm,
 					    &item->mm_node,
-					    mem->size, 0,
-					    DRM_MM_SEARCH_DEFAULT);
+					    mem->size);
 		offset = item->mm_node.start;
 #endif
 	}

drivers/gpu/drm/tegra/gem.c

@@ -128,8 +128,8 @@ static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
 	if (!bo->mm)
 		return -ENOMEM;
 
-	err = drm_mm_insert_node_generic(&tegra->mm, bo->mm, bo->gem.size,
-					 PAGE_SIZE, 0, 0, 0);
+	err = drm_mm_insert_node_generic(&tegra->mm,
+					 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0);
 	if (err < 0) {
 		dev_err(tegra->drm->dev, "out of I/O virtual memory: %zd\n",
 			err);

drivers/gpu/drm/ttm/ttm_bo_manager.c

@@ -54,9 +54,8 @@ static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
 {
 	struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
 	struct drm_mm *mm = &rman->mm;
-	struct drm_mm_node *node = NULL;
-	enum drm_mm_search_flags sflags = DRM_MM_SEARCH_BEST;
-	enum drm_mm_allocator_flags aflags = DRM_MM_CREATE_DEFAULT;
+	struct drm_mm_node *node;
+	enum drm_mm_insert_mode mode;
 	unsigned long lpfn;
 	int ret;
 
@@ -68,16 +67,15 @@ static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
 	if (!node)
 		return -ENOMEM;
 
-	if (place->flags & TTM_PL_FLAG_TOPDOWN) {
-		sflags = DRM_MM_SEARCH_BELOW;
-		aflags = DRM_MM_CREATE_TOP;
-	}
+	mode = DRM_MM_INSERT_BEST;
+	if (place->flags & TTM_PL_FLAG_TOPDOWN)
+		mode = DRM_MM_INSERT_HIGH;
 
 	spin_lock(&rman->lock);
-	ret = drm_mm_insert_node_in_range_generic(mm, node, mem->num_pages,
+	ret = drm_mm_insert_node_in_range(mm, node,
+					  mem->num_pages,
 					  mem->page_alignment, 0,
-					  place->fpfn, lpfn,
-					  sflags, aflags);
+					  place->fpfn, lpfn, mode);
 	spin_unlock(&rman->lock);
 
 	if (unlikely(ret)) {

drivers/gpu/drm/vc4/vc4_crtc.c

@@ -593,7 +593,7 @@ static int vc4_crtc_atomic_check(struct drm_crtc *crtc,
 
 	spin_lock_irqsave(&vc4->hvs->mm_lock, flags);
 	ret = drm_mm_insert_node(&vc4->hvs->dlist_mm, &vc4_state->mm,
-				 dlist_count, 1, 0);
+				 dlist_count);
 	spin_unlock_irqrestore(&vc4->hvs->mm_lock, flags);
 	if (ret)
 		return ret;

drivers/gpu/drm/vc4/vc4_hvs.c

@@ -141,8 +141,7 @@ static int vc4_hvs_upload_linear_kernel(struct vc4_hvs *hvs,
 	int ret, i;
 	u32 __iomem *dst_kernel;
 
-	ret = drm_mm_insert_node(&hvs->dlist_mm, space, VC4_KERNEL_DWORDS, 1,
-				 0);
+	ret = drm_mm_insert_node(&hvs->dlist_mm, space, VC4_KERNEL_DWORDS);
 	if (ret) {
 		DRM_ERROR("Failed to allocate space for filter kernel: %d\n",
 			  ret);

drivers/gpu/drm/vc4/vc4_plane.c

@@ -514,9 +514,9 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
 	if (lbm_size) {
 		if (!vc4_state->lbm.allocated) {
 			spin_lock_irqsave(&vc4->hvs->mm_lock, irqflags);
-			ret = drm_mm_insert_node(&vc4->hvs->lbm_mm,
-						 &vc4_state->lbm,
-						 lbm_size, 32, 0);
+			ret = drm_mm_insert_node_generic(&vc4->hvs->lbm_mm,
+							 &vc4_state->lbm,
+							 lbm_size, 32, 0, 0);
 			spin_unlock_irqrestore(&vc4->hvs->mm_lock, irqflags);
 		} else {
 			WARN_ON_ONCE(lbm_size != vc4_state->lbm.size);

drivers/gpu/drm/via/via_mm.c

@@ -140,11 +140,11 @@ int via_mem_alloc(struct drm_device *dev, void *data,
 	if (mem->type == VIA_MEM_AGP)
 		retval = drm_mm_insert_node(&dev_priv->agp_mm,
 					    &item->mm_node,
-					    tmpSize, 0, DRM_MM_SEARCH_DEFAULT);
+					    tmpSize);
 	else
 		retval = drm_mm_insert_node(&dev_priv->vram_mm,
 					    &item->mm_node,
-					    tmpSize, 0, DRM_MM_SEARCH_DEFAULT);
+					    tmpSize);
 	if (retval)
 		goto fail_alloc;
 

drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c

@@ -673,16 +673,10 @@ static bool vmw_cmdbuf_try_alloc(struct vmw_cmdbuf_man *man,
  
 	memset(info->node, 0, sizeof(*info->node));
 	spin_lock_bh(&man->lock);
-	ret = drm_mm_insert_node_generic(&man->mm, info->node, info->page_size,
-					 0, 0,
-					 DRM_MM_SEARCH_DEFAULT,
-					 DRM_MM_CREATE_DEFAULT);
+	ret = drm_mm_insert_node(&man->mm, info->node, info->page_size);
 	if (ret) {
 		vmw_cmdbuf_man_process(man);
-		ret = drm_mm_insert_node_generic(&man->mm, info->node,
-						 info->page_size, 0, 0,
-						 DRM_MM_SEARCH_DEFAULT,
-						 DRM_MM_CREATE_DEFAULT);
+		ret = drm_mm_insert_node(&man->mm, info->node, info->page_size);
 	}
 
 	spin_unlock_bh(&man->lock);

include/drm/drm_mm.h

@@ -53,19 +53,62 @@
 #define DRM_MM_BUG_ON(expr) BUILD_BUG_ON_INVALID(expr)
 #endif
 
-enum drm_mm_search_flags {
-	DRM_MM_SEARCH_DEFAULT =		0,
-	DRM_MM_SEARCH_BEST =		1 << 0,
-	DRM_MM_SEARCH_BELOW =		1 << 1,
-};
+/**
+ * enum drm_mm_insert_mode - control search and allocation behaviour
+ *
+ * The &struct drm_mm range manager supports finding a suitable modes using
+ * a number of search trees. These trees are oranised by size, by address and
+ * in most recent eviction order. This allows the user to find either the
+ * smallest hole to reuse, the lowest or highest address to reuse, or simply
+ * reuse the most recent eviction that fits. When allocating the &drm_mm_node
+ * from within the hole, the &drm_mm_insert_mode also dictate whether to
+ * allocate the lowest matching address or the highest.
+ */
+enum drm_mm_insert_mode {
+	/**
+	 * @DRM_MM_INSERT_BEST:
+	 *
+	 * Search for the smallest hole (within the search range) that fits
+	 * the desired node.
+	 *
+	 * Allocates the node from the bottom of the found hole.
+	 */
+	DRM_MM_INSERT_BEST = 0,
 
-enum drm_mm_allocator_flags {
-	DRM_MM_CREATE_DEFAULT =		0,
-	DRM_MM_CREATE_TOP =		1 << 0,
-};
+	/**
+	 * @DRM_MM_INSERT_LOW:
+	 *
+	 * Search for the lowest hole (address closest to 0, within the search
+	 * range) that fits the desired node.
+	 *
+	 * Allocates the node from the bottom of the found hole.
+	 */
+	DRM_MM_INSERT_LOW,
 
-#define DRM_MM_BOTTOMUP DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT
-#define DRM_MM_TOPDOWN DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP
+	/**
+	 * @DRM_MM_INSERT_HIGH:
+	 *
+	 * Search for the highest hole (address closest to U64_MAX, within the
+	 * search range) that fits the desired node.
+	 *
+	 * Allocates the node from the *top* of the found hole. The specified
+	 * alignment for the node is applied to the base of the node
+	 * (&drm_mm_node.start).
+	 */
+	DRM_MM_INSERT_HIGH,
+
+	/**
+	 * @DRM_MM_INSERT_EVICT:
+	 *
+	 * Search for the most recently evicted hole (within the search range)
+	 * that fits the desired node. This is appropriate for use immediately
+	 * after performing an eviction scan (see drm_mm_scan_init()) and
+	 * removing the selected nodes to form a hole.
+	 *
+	 * Allocates the node from the bottom of the found hole.
+	 */
+	DRM_MM_INSERT_EVICT,
+};
 
 /**
  * struct drm_mm_node - allocated block in the DRM allocator
@@ -84,14 +127,16 @@ struct drm_mm_node {
 	/** @size: Size of the allocated block. */
 	u64 size;
 	/* private: */
+	struct drm_mm *mm;
 	struct list_head node_list;
 	struct list_head hole_stack;
 	struct rb_node rb;
-	unsigned hole_follows : 1;
-	unsigned allocated : 1;
-	bool scanned_block : 1;
+	struct rb_node rb_hole_size;
+	struct rb_node rb_hole_addr;
 	u64 __subtree_last;
-	struct drm_mm *mm;
+	u64 hole_size;
+	bool allocated : 1;
+	bool scanned_block : 1;
 #ifdef CONFIG_DRM_DEBUG_MM
 	depot_stack_handle_t stack;
 #endif
@@ -127,6 +172,8 @@ struct drm_mm {
 	struct drm_mm_node head_node;
 	/* Keep an interval_tree for fast lookup of drm_mm_nodes by address. */
 	struct rb_root interval_tree;
+	struct rb_root holes_size;
+	struct rb_root holes_addr;
 
 	unsigned long scan_active;
 };
@@ -155,7 +202,7 @@ struct drm_mm_scan {
 	u64 hit_end;
 
 	unsigned long color;
-	unsigned int flags;
+	enum drm_mm_insert_mode mode;
 };
 
 /**
@@ -208,7 +255,7 @@ static inline bool drm_mm_initialized(const struct drm_mm *mm)
  */
 static inline bool drm_mm_hole_follows(const struct drm_mm_node *node)
 {
-	return node->hole_follows;
+	return node->hole_size;
 }
 
 static inline u64 __drm_mm_hole_node_start(const struct drm_mm_node *hole_node)
@@ -291,17 +338,9 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node)
 #define drm_mm_for_each_node_safe(entry, next, mm) \
 	list_for_each_entry_safe(entry, next, drm_mm_nodes(mm), node_list)
 
-#define __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, backwards) \
-	for (entry = list_entry((backwards) ? (mm)->hole_stack.prev : (mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
-	     &entry->hole_stack != &(mm)->hole_stack ? \
-	     hole_start = drm_mm_hole_node_start(entry), \
-	     hole_end = drm_mm_hole_node_end(entry), \
-	     1 : 0; \
-	     entry = list_entry((backwards) ? entry->hole_stack.prev : entry->hole_stack.next, struct drm_mm_node, hole_stack))
-
 /**
  * drm_mm_for_each_hole - iterator to walk over all holes
- * @entry: &drm_mm_node used internally to track progress
+ * @pos: &drm_mm_node used internally to track progress
  * @mm: &drm_mm allocator to walk
  * @hole_start: ulong variable to assign the hole start to on each iteration
  * @hole_end: ulong variable to assign the hole end to on each iteration
@@ -314,57 +353,28 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node)
  * Implementation Note:
  * We need to inline list_for_each_entry in order to be able to set hole_start
  * and hole_end on each iteration while keeping the macro sane.
- *
- * The __drm_mm_for_each_hole version is similar, but with added support for
- * going backwards.
  */
-#define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
-	__drm_mm_for_each_hole(entry, mm, hole_start, hole_end, 0)
+#define drm_mm_for_each_hole(pos, mm, hole_start, hole_end) \
+	for (pos = list_first_entry(&(mm)->hole_stack, \
+				    typeof(*pos), hole_stack); \
+	     &pos->hole_stack != &(mm)->hole_stack ? \
+	     hole_start = drm_mm_hole_node_start(pos), \
+	     hole_end = hole_start + pos->hole_size, \
+	     1 : 0; \
+	     pos = list_next_entry(pos, hole_stack))
 
 /*
  * Basic range manager support (drm_mm.c)
  */
 int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
-int drm_mm_insert_node_in_range_generic(struct drm_mm *mm,
-					struct drm_mm_node *node,
-					u64 size,
-					u64 alignment,
-					unsigned long color,
-					u64 start,
-					u64 end,
-					enum drm_mm_search_flags sflags,
-					enum drm_mm_allocator_flags aflags);
-
-/**
- * drm_mm_insert_node_in_range - ranged search for space and insert @node
- * @mm: drm_mm to allocate from
- * @node: preallocate node to insert
- * @size: size of the allocation
- * @alignment: alignment of the allocation
- * @start: start of the allowed range for this node
- * @end: end of the allowed range for this node
- * @flags: flags to fine-tune the allocation
- *
- * This is a simplified version of drm_mm_insert_node_in_range_generic() with
- * @color set to 0.
- *
- * The preallocated node must be cleared to 0.
- *
- * Returns:
- * 0 on success, -ENOSPC if there's no suitable hole.
- */
-static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
-					      struct drm_mm_node *node,
-					      u64 size,
-					      u64 alignment,
-					      u64 start,
-					      u64 end,
-					      enum drm_mm_search_flags flags)
-{
-	return drm_mm_insert_node_in_range_generic(mm, node, size, alignment,
-						   0, start, end, flags,
-						   DRM_MM_CREATE_DEFAULT);
-}
+int drm_mm_insert_node_in_range(struct drm_mm *mm,
+				struct drm_mm_node *node,
+				u64 size,
+				u64 alignment,
+				unsigned long color,
+				u64 start,
+				u64 end,
+				enum drm_mm_insert_mode mode);
 
 /**
  * drm_mm_insert_node_generic - search for space and insert @node
@@ -373,8 +383,7 @@ static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
  * @size: size of the allocation
  * @alignment: alignment of the allocation
  * @color: opaque tag value to use for this node
- * @sflags: flags to fine-tune the allocation search
- * @aflags: flags to fine-tune the allocation behavior
+ * @mode: fine-tune the allocation search and placement
  *
  * This is a simplified version of drm_mm_insert_node_in_range_generic() with no
  * range restrictions applied.
@@ -388,13 +397,11 @@ static inline int
 drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node,
 			   u64 size, u64 alignment,
 			   unsigned long color,
-			   enum drm_mm_search_flags sflags,
-			   enum drm_mm_allocator_flags aflags)
+			   enum drm_mm_insert_mode mode)
 {
-	return drm_mm_insert_node_in_range_generic(mm, node,
-						   size, alignment, 0,
-						   0, U64_MAX,
-						   sflags, aflags);
+	return drm_mm_insert_node_in_range(mm, node,
+					   size, alignment, color,
+					   0, U64_MAX, mode);
 }
 
 /**
@@ -402,8 +409,6 @@ drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node,
  * @mm: drm_mm to allocate from
  * @node: preallocate node to insert
  * @size: size of the allocation
- * @alignment: alignment of the allocation
- * @flags: flags to fine-tune the allocation
  *
  * This is a simplified version of drm_mm_insert_node_generic() with @color set
  * to 0.
@@ -415,13 +420,9 @@ drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node,
  */
 static inline int drm_mm_insert_node(struct drm_mm *mm,
 				     struct drm_mm_node *node,
-				     u64 size,
-				     u64 alignment,
-				     enum drm_mm_search_flags flags)
+				     u64 size)
 {
-	return drm_mm_insert_node_generic(mm, node,
-					  size, alignment, 0,
-					  flags, DRM_MM_CREATE_DEFAULT);
+	return drm_mm_insert_node_generic(mm, node, size, 0, 0, 0);
 }
 
 void drm_mm_remove_node(struct drm_mm_node *node);
@@ -468,7 +469,7 @@ void drm_mm_scan_init_with_range(struct drm_mm_scan *scan,
 				 struct drm_mm *mm,
 				 u64 size, u64 alignment, unsigned long color,
 				 u64 start, u64 end,
-				 unsigned int flags);
+				 enum drm_mm_insert_mode mode);
 
 /**
  * drm_mm_scan_init - initialize lru scanning
@@ -477,7 +478,7 @@ void drm_mm_scan_init_with_range(struct drm_mm_scan *scan,
  * @size: size of the allocation
  * @alignment: alignment of the allocation
  * @color: opaque tag value to use for the allocation
- * @flags: flags to specify how the allocation will be performed afterwards
+ * @mode: fine-tune the allocation search and placement
  *
  * This is a simplified version of drm_mm_scan_init_with_range() with no range
  * restrictions applied.
@@ -494,12 +495,11 @@ static inline void drm_mm_scan_init(struct drm_mm_scan *scan,
 				    u64 size,
 				    u64 alignment,
 				    unsigned long color,
-				    unsigned int flags)
+				    enum drm_mm_insert_mode mode)
 {
 	drm_mm_scan_init_with_range(scan, mm,
 				    size, alignment, color,
-				    0, U64_MAX,
-				    flags);
+				    0, U64_MAX, mode);
 }
 
 bool drm_mm_scan_add_block(struct drm_mm_scan *scan,