21  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
37  * an RB-tree is used instead. At least if we expect heavy fragmentation.
42  * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
88  * Two behaviors are supported for searching and allocating: bottom-up and
89  * top-down. The default is bottom-up. Top-down allocation can be used if the
95  * Note that this range allocator is not thread-safe, drivers need to protect
115 	node->stack = stack_depot_save(entries, n, GFP_NOWAIT);  in save_stack()
128 		if (!node->stack) {  in show_leaks()
130 				  node->start, node->size);  in show_leaks()
134 		stack_depot_snprint(node->stack, buf, BUFSZ, 0);  in show_leaks()
136 			  node->start, node->size, buf);  in show_leaks()
149 #define START(node) ((node)->start)
150 #define LAST(node)  ((node)->start + (node)->size - 1)
159 	return drm_mm_interval_tree_iter_first((struct rb_root_cached *)&mm->interval_tree,  in INTERVAL_TREE_DEFINE()
160 					       start, last) ?: (struct drm_mm_node *)&mm->head_node;  in INTERVAL_TREE_DEFINE()
167 	struct drm_mm *mm = hole_node->mm;  in drm_mm_interval_tree_add_node()
172 	node->__subtree_last = LAST(node);  in drm_mm_interval_tree_add_node()
175 		rb = &hole_node->rb;  in drm_mm_interval_tree_add_node()
178 			if (parent->__subtree_last >= node->__subtree_last)  in drm_mm_interval_tree_add_node()
181 			parent->__subtree_last = node->__subtree_last;  in drm_mm_interval_tree_add_node()
185 		rb = &hole_node->rb;  in drm_mm_interval_tree_add_node()
186 		link = &hole_node->rb.rb_right;  in drm_mm_interval_tree_add_node()
190 		link = &mm->interval_tree.rb_root.rb_node;  in drm_mm_interval_tree_add_node()
197 		if (parent->__subtree_last < node->__subtree_last)  in drm_mm_interval_tree_add_node()
198 			parent->__subtree_last = node->__subtree_last;  in drm_mm_interval_tree_add_node()
199 		if (node->start < parent->start) {  in drm_mm_interval_tree_add_node()
200 			link = &parent->rb.rb_left;  in drm_mm_interval_tree_add_node()
202 			link = &parent->rb.rb_right;  in drm_mm_interval_tree_add_node()
207 	rb_link_node(&node->rb, rb, link);  in drm_mm_interval_tree_add_node()
208 	rb_insert_augmented_cached(&node->rb, &mm->interval_tree, leftmost,  in drm_mm_interval_tree_add_node()
212 #define HOLE_SIZE(NODE) ((NODE)->hole_size)
217 	return rb_entry(rb, struct drm_mm_node, rb_hole_size)->hole_size;  in rb_to_hole_size()
223 	struct rb_node **link = &root->rb_root.rb_node, *rb = NULL;  in insert_hole_size()
224 	u64 x = node->hole_size;  in insert_hole_size()
230 			link = &rb->rb_left;  in insert_hole_size()
232 			link = &rb->rb_right;  in insert_hole_size()
237 	rb_link_node(&node->rb_hole_size, rb, link);  in insert_hole_size()
238 	rb_insert_color_cached(&node->rb_hole_size, root, first);  in insert_hole_size()
247 	struct rb_node **link = &root->rb_node, *rb_parent = NULL;  in RB_DECLARE_CALLBACKS_MAX()
248 	u64 start = HOLE_ADDR(node), subtree_max_hole = node->subtree_max_hole;  in RB_DECLARE_CALLBACKS_MAX()
254 		if (parent->subtree_max_hole < subtree_max_hole)  in RB_DECLARE_CALLBACKS_MAX()
255 			parent->subtree_max_hole = subtree_max_hole;  in RB_DECLARE_CALLBACKS_MAX()
257 			link = &parent->rb_hole_addr.rb_left;  in RB_DECLARE_CALLBACKS_MAX()
259 			link = &parent->rb_hole_addr.rb_right;  in RB_DECLARE_CALLBACKS_MAX()
262 	rb_link_node(&node->rb_hole_addr, rb_parent, link);  in RB_DECLARE_CALLBACKS_MAX()
263 	rb_insert_augmented(&node->rb_hole_addr, root, &augment_callbacks);  in RB_DECLARE_CALLBACKS_MAX()
268 	struct drm_mm *mm = node->mm;  in add_hole()
270 	node->hole_size =  in add_hole()
271 		__drm_mm_hole_node_end(node) - __drm_mm_hole_node_start(node);  in add_hole()
272 	node->subtree_max_hole = node->hole_size;  in add_hole()
275 	insert_hole_size(&mm->holes_size, node);  in add_hole()
276 	insert_hole_addr(&mm->holes_addr, node);  in add_hole()
278 	list_add(&node->hole_stack, &mm->hole_stack);  in add_hole()
285 	list_del(&node->hole_stack);  in rm_hole()
286 	rb_erase_cached(&node->rb_hole_size, &node->mm->holes_size);  in rm_hole()
287 	rb_erase_augmented(&node->rb_hole_addr, &node->mm->holes_addr,  in rm_hole()
289 	node->hole_size = 0;  in rm_hole()
290 	node->subtree_max_hole = 0;  in rm_hole()
307 	struct rb_node *rb = mm->holes_size.rb_root.rb_node;  in best_hole()
314 		if (size <= node->hole_size) {  in best_hole()
316 			rb = rb->rb_right;  in best_hole()
318 			rb = rb->rb_left;  in best_hole()
327 	return rb && rb_hole_addr_to_node(rb)->subtree_max_hole >= size;  in usable_hole_addr()
332 	struct rb_node *rb = mm->holes_addr.rb_node;  in find_hole_addr()
345 			rb = node->rb_hole_addr.rb_left;  in find_hole_addr()
346 		else if (addr > hole_start + node->hole_size)  in find_hole_addr()
347 			rb = node->rb_hole_addr.rb_right;  in find_hole_addr()
372 		return list_first_entry_or_null(&mm->hole_stack,  in first_hole()
379  * DECLARE_NEXT_HOLE_ADDR - macro to declare next hole functions
392 	struct rb_node *parent, *node = &entry->rb_hole_addr;		\
397 	if (usable_hole_addr(node->first, size)) {			\
398 		node = node->first;					\
399 		while (usable_hole_addr(node->last, size))		\
400 			node = node->last;				\
404 	while ((parent = rb_parent(node)) && node == parent->first)	\
422 		return rb_hole_size_to_node(rb_prev(&node->rb_hole_size));  in DECLARE_NEXT_HOLE_ADDR()
432 		return &node->hole_stack == &mm->hole_stack ? NULL : node;  in DECLARE_NEXT_HOLE_ADDR()
437  * drm_mm_reserve_node - insert an pre-initialized node
441  * This functions inserts an already set-up &drm_mm_node into the allocator,
444  * preallocated objects which must be set-up before the range allocator can be
445  * set-up, e.g. when taking over a firmware framebuffer.
448  * 0 on success, -ENOSPC if there's no hole where @node is.
457 	end = node->start + node->size;  in drm_mm_reserve_node()
458 	if (unlikely(end <= node->start))  in drm_mm_reserve_node()
459 		return -ENOSPC;  in drm_mm_reserve_node()
462 	hole = find_hole_addr(mm, node->start, 0);  in drm_mm_reserve_node()
464 		return -ENOSPC;  in drm_mm_reserve_node()
467 	adj_end = hole_end = hole_start + hole->hole_size;  in drm_mm_reserve_node()
469 	if (mm->color_adjust)  in drm_mm_reserve_node()
470 		mm->color_adjust(hole, node->color, &adj_start, &adj_end);  in drm_mm_reserve_node()
472 	if (adj_start > node->start || adj_end < end)  in drm_mm_reserve_node()
473 		return -ENOSPC;  in drm_mm_reserve_node()
475 	node->mm = mm;  in drm_mm_reserve_node()
477 	__set_bit(DRM_MM_NODE_ALLOCATED_BIT, &node->flags);  in drm_mm_reserve_node()
478 	list_add(&node->node_list, &hole->node_list);  in drm_mm_reserve_node()
480 	node->hole_size = 0;  in drm_mm_reserve_node()
483 	if (node->start > hole_start)  in drm_mm_reserve_node()
499  * drm_mm_insert_node_in_range - ranged search for space and insert @node
507  * @mode: fine-tune the allocation search and placement
512  * 0 on success, -ENOSPC if there's no suitable hole.
527 	if (unlikely(size == 0 || range_end - range_start < size))  in drm_mm_insert_node_in_range()
528 		return -ENOSPC;  in drm_mm_insert_node_in_range()
530 	if (rb_to_hole_size_or_zero(rb_first_cached(&mm->holes_size)) < size)  in drm_mm_insert_node_in_range()
531 		return -ENOSPC;  in drm_mm_insert_node_in_range()
539 	remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0;  in drm_mm_insert_node_in_range()
544 		u64 hole_end = hole_start + hole->hole_size;  in drm_mm_insert_node_in_range()
556 		if (mm->color_adjust)  in drm_mm_insert_node_in_range()
557 			mm->color_adjust(hole, color, &col_start, &col_end);  in drm_mm_insert_node_in_range()
562 		if (adj_end <= adj_start || adj_end - adj_start < size)  in drm_mm_insert_node_in_range()
566 			adj_start = adj_end - size;  in drm_mm_insert_node_in_range()
576 				adj_start -= rem;  in drm_mm_insert_node_in_range()
581 				    min(col_end, range_end) - adj_start < size)  in drm_mm_insert_node_in_range()
585 				    adj_end - adj_start < size)  in drm_mm_insert_node_in_range()
590 		node->mm = mm;  in drm_mm_insert_node_in_range()
591 		node->size = size;  in drm_mm_insert_node_in_range()
592 		node->start = adj_start;  in drm_mm_insert_node_in_range()
593 		node->color = color;  in drm_mm_insert_node_in_range()
594 		node->hole_size = 0;  in drm_mm_insert_node_in_range()
596 		__set_bit(DRM_MM_NODE_ALLOCATED_BIT, &node->flags);  in drm_mm_insert_node_in_range()
597 		list_add(&node->node_list, &hole->node_list);  in drm_mm_insert_node_in_range()
610 	return -ENOSPC;  in drm_mm_insert_node_in_range()
616 	return test_bit(DRM_MM_NODE_SCANNED_BIT, &node->flags);  in drm_mm_node_scanned_block()
620  * drm_mm_remove_node - Remove a memory node from the allocator.
624  * be cleared again before it can be re-inserted into this or any other drm_mm
629 	struct drm_mm *mm = node->mm;  in drm_mm_remove_node()
640 	drm_mm_interval_tree_remove(node, &mm->interval_tree);  in drm_mm_remove_node()
641 	list_del(&node->node_list);  in drm_mm_remove_node()
647 	clear_bit_unlock(DRM_MM_NODE_ALLOCATED_BIT, &node->flags);  in drm_mm_remove_node()
661  * The DRM range allocator supports this use-case through the scanning
684  * drm_mm_scan_init_with_range - initialize range-restricted lru scanning
692  * @mode: fine-tune the allocation search and placement
698  * As long as the scan list is non-empty, no other operations than
711 	DRM_MM_BUG_ON(!size || size > end - start);  in drm_mm_scan_init_with_range()
712 	DRM_MM_BUG_ON(mm->scan_active);  in drm_mm_scan_init_with_range()
714 	scan->mm = mm;  in drm_mm_scan_init_with_range()
719 	scan->color = color;  in drm_mm_scan_init_with_range()
720 	scan->alignment = alignment;  in drm_mm_scan_init_with_range()
721 	scan->remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0;  in drm_mm_scan_init_with_range()
722 	scan->size = size;  in drm_mm_scan_init_with_range()
723 	scan->mode = mode;  in drm_mm_scan_init_with_range()
726 	scan->range_start = start;  in drm_mm_scan_init_with_range()
727 	scan->range_end = end;  in drm_mm_scan_init_with_range()
729 	scan->hit_start = U64_MAX;  in drm_mm_scan_init_with_range()
730 	scan->hit_end = 0;  in drm_mm_scan_init_with_range()
735  * drm_mm_scan_add_block - add a node to the scan list
748 	struct drm_mm *mm = scan->mm;  in drm_mm_scan_add_block()
754 	DRM_MM_BUG_ON(node->mm != mm);  in drm_mm_scan_add_block()
757 	__set_bit(DRM_MM_NODE_SCANNED_BIT, &node->flags);  in drm_mm_scan_add_block()
758 	mm->scan_active++;  in drm_mm_scan_add_block()
767 	__list_del_entry(&node->node_list);  in drm_mm_scan_add_block()
774 	if (mm->color_adjust)  in drm_mm_scan_add_block()
775 		mm->color_adjust(hole, scan->color, &col_start, &col_end);  in drm_mm_scan_add_block()
777 	adj_start = max(col_start, scan->range_start);  in drm_mm_scan_add_block()
778 	adj_end = min(col_end, scan->range_end);  in drm_mm_scan_add_block()
779 	if (adj_end <= adj_start || adj_end - adj_start < scan->size)  in drm_mm_scan_add_block()
782 	if (scan->mode == DRM_MM_INSERT_HIGH)  in drm_mm_scan_add_block()
783 		adj_start = adj_end - scan->size;  in drm_mm_scan_add_block()
785 	if (scan->alignment) {  in drm_mm_scan_add_block()
788 		if (likely(scan->remainder_mask))  in drm_mm_scan_add_block()
789 			rem = adj_start & scan->remainder_mask;  in drm_mm_scan_add_block()
791 			div64_u64_rem(adj_start, scan->alignment, &rem);  in drm_mm_scan_add_block()
793 			adj_start -= rem;  in drm_mm_scan_add_block()
794 			if (scan->mode != DRM_MM_INSERT_HIGH)  in drm_mm_scan_add_block()
795 				adj_start += scan->alignment;  in drm_mm_scan_add_block()
796 			if (adj_start < max(col_start, scan->range_start) ||  in drm_mm_scan_add_block()
797 			    min(col_end, scan->range_end) - adj_start < scan->size)  in drm_mm_scan_add_block()
801 			    adj_end - adj_start < scan->size)  in drm_mm_scan_add_block()
806 	scan->hit_start = adj_start;  in drm_mm_scan_add_block()
807 	scan->hit_end = adj_start + scan->size;  in drm_mm_scan_add_block()
809 	DRM_MM_BUG_ON(scan->hit_start >= scan->hit_end);  in drm_mm_scan_add_block()
810 	DRM_MM_BUG_ON(scan->hit_start < hole_start);  in drm_mm_scan_add_block()
811 	DRM_MM_BUG_ON(scan->hit_end > hole_end);  in drm_mm_scan_add_block()
818  * drm_mm_scan_remove_block - remove a node from the scan list
841 	DRM_MM_BUG_ON(node->mm != scan->mm);  in drm_mm_scan_remove_block()
843 	__clear_bit(DRM_MM_NODE_SCANNED_BIT, &node->flags);  in drm_mm_scan_remove_block()
845 	DRM_MM_BUG_ON(!node->mm->scan_active);  in drm_mm_scan_remove_block()
846 	node->mm->scan_active--;  in drm_mm_scan_remove_block()
852 	 * backwards correctly we check that prev_node->next == node->next,  in drm_mm_scan_remove_block()
859 	list_add(&node->node_list, &prev_node->node_list);  in drm_mm_scan_remove_block()
861 	return (node->start + node->size > scan->hit_start &&  in drm_mm_scan_remove_block()
862 		node->start < scan->hit_end);  in drm_mm_scan_remove_block()
867  * drm_mm_scan_color_evict - evict overlapping nodes on either side of hole
879 	struct drm_mm *mm = scan->mm;  in drm_mm_scan_color_evict()
883 	DRM_MM_BUG_ON(list_empty(&mm->hole_stack));  in drm_mm_scan_color_evict()
885 	if (!mm->color_adjust)  in drm_mm_scan_color_evict()
890 	 * in the hole_stack list, but due to side-effects in the driver it  in drm_mm_scan_color_evict()
893 	list_for_each_entry(hole, &mm->hole_stack, hole_stack) {  in drm_mm_scan_color_evict()
895 		hole_end = hole_start + hole->hole_size;  in drm_mm_scan_color_evict()
897 		if (hole_start <= scan->hit_start &&  in drm_mm_scan_color_evict()
898 		    hole_end >= scan->hit_end)  in drm_mm_scan_color_evict()
903 	DRM_MM_BUG_ON(&hole->hole_stack == &mm->hole_stack);  in drm_mm_scan_color_evict()
904 	if (unlikely(&hole->hole_stack == &mm->hole_stack))  in drm_mm_scan_color_evict()
907 	DRM_MM_BUG_ON(hole_start > scan->hit_start);  in drm_mm_scan_color_evict()
908 	DRM_MM_BUG_ON(hole_end < scan->hit_end);  in drm_mm_scan_color_evict()
910 	mm->color_adjust(hole, scan->color, &hole_start, &hole_end);  in drm_mm_scan_color_evict()
911 	if (hole_start > scan->hit_start)  in drm_mm_scan_color_evict()
913 	if (hole_end < scan->hit_end)  in drm_mm_scan_color_evict()
921  * drm_mm_init - initialize a drm-mm allocator
932 	mm->color_adjust = NULL;  in drm_mm_init()
934 	INIT_LIST_HEAD(&mm->hole_stack);  in drm_mm_init()
935 	mm->interval_tree = RB_ROOT_CACHED;  in drm_mm_init()
936 	mm->holes_size = RB_ROOT_CACHED;  in drm_mm_init()
937 	mm->holes_addr = RB_ROOT;  in drm_mm_init()
940 	INIT_LIST_HEAD(&mm->head_node.node_list);  in drm_mm_init()
941 	mm->head_node.flags = 0;  in drm_mm_init()
942 	mm->head_node.mm = mm;  in drm_mm_init()
943 	mm->head_node.start = start + size;  in drm_mm_init()
944 	mm->head_node.size = -size;  in drm_mm_init()
945 	add_hole(&mm->head_node);  in drm_mm_init()
947 	mm->scan_active = 0;  in drm_mm_init()
956  * drm_mm_takedown - clean up a drm_mm allocator
974 	size = entry->hole_size;  in drm_mm_dump_hole()
977 		drm_printf(p, "%#018llx-%#018llx: %llu: free\n",  in drm_mm_dump_hole()
984  * drm_mm_print - print allocator state
993 	total_free += drm_mm_dump_hole(p, &mm->head_node);  in drm_mm_print()
996 		drm_printf(p, "%#018llx-%#018llx: %llu: used\n", entry->start,  in drm_mm_print()
997 			   entry->start + entry->size, entry->size);  in drm_mm_print()
998 		total_used += entry->size;  in drm_mm_print()