1 /* SPDX-License-Identifier: GPL-2.0 */
11 #include "disk-io.h"
84  * Now it only supports iteration of tree block in commit root.
103 	btrfs_free_path(iter->path);  in btrfs_backref_iter_free()
112 	return iter->path->nodes[0];  in btrfs_backref_get_eb()
116  * For metadata with EXTENT_ITEM key (non-skinny) case, the first inline data
124 	if (iter->cur_key.type == BTRFS_EXTENT_ITEM_KEY &&  in btrfs_backref_has_tree_block_info()
125 	    iter->cur_ptr - iter->item_ptr == sizeof(struct btrfs_extent_item))  in btrfs_backref_has_tree_block_info()
137 	if (iter->cur_key.type == BTRFS_EXTENT_ITEM_KEY ||  in btrfs_backref_iter_is_inline_ref()
138 	    iter->cur_key.type == BTRFS_METADATA_ITEM_KEY)  in btrfs_backref_iter_is_inline_ref()
145 	iter->bytenr = 0;  in btrfs_backref_iter_release()
146 	iter->item_ptr = 0;  in btrfs_backref_iter_release()
147 	iter->cur_ptr = 0;  in btrfs_backref_iter_release()
148 	iter->end_ptr = 0;  in btrfs_backref_iter_release()
149 	btrfs_release_path(iter->path);  in btrfs_backref_iter_release()
150 	memset(&iter->cur_key, 0, sizeof(iter->cur_key));  in btrfs_backref_iter_release()
154  * Backref cache related structures
156  * The whole objective of backref_cache is to build a bi-directional map
161  * Represent a tree block in the backref cache
170 	/* Objectid of tree block owner, can be not uptodate */
182 	/* Extent buffer got by COWing the block */
184 	/* Level of the tree block */
186 	/* Is the block in a non-shareable tree */
188 	/* 1 if no child node is in the cache */
192 	/* Has the block been processed */
194 	/* Have backrefs of this block been checked */
197 	 * 1 if corresponding block has been COWed but some upper level block
205 	 * For generic purpose backref cache, where we only care if it's a reloc
233 	/* Red black tree of all backref nodes in the cache */
238 	 * List of blocks that have been COWed but some block pointers in upper
254 	/* List of unchecked backref edges during backref cache build */
257 	/* List of useless backref nodes during backref cache build */
263 	 * Whether this cache is for relocation
265 	 * Reloction backref cache require more info for reloc root compared
266 	 * to generic backref cache.
272 			      struct btrfs_backref_cache *cache, int is_reloc);
274 		struct btrfs_backref_cache *cache, u64 bytenr, int level);
276 		struct btrfs_backref_cache *cache);
285 	ASSERT(upper && lower && upper->level == lower->level + 1);  in btrfs_backref_link_edge()
286 	edge->node[LOWER] = lower;  in btrfs_backref_link_edge()
287 	edge->node[UPPER] = upper;  in btrfs_backref_link_edge()
289 		list_add_tail(&edge->list[LOWER], &lower->upper);  in btrfs_backref_link_edge()
291 		list_add_tail(&edge->list[UPPER], &upper->lower);  in btrfs_backref_link_edge()
294 static inline void btrfs_backref_free_node(struct btrfs_backref_cache *cache,  in btrfs_backref_free_node()  argument
298 		ASSERT(list_empty(&node->list));  in btrfs_backref_free_node()
299 		ASSERT(list_empty(&node->lower));  in btrfs_backref_free_node()
300 		ASSERT(node->eb == NULL);  in btrfs_backref_free_node()
301 		cache->nr_nodes--;  in btrfs_backref_free_node()
302 		btrfs_put_root(node->root);  in btrfs_backref_free_node()
307 static inline void btrfs_backref_free_edge(struct btrfs_backref_cache *cache,  in btrfs_backref_free_edge()  argument
311 		cache->nr_edges--;  in btrfs_backref_free_edge()
319 	if (node->locked) {  in btrfs_backref_unlock_node_buffer()
320 		btrfs_tree_unlock(node->eb);  in btrfs_backref_unlock_node_buffer()
321 		node->locked = 0;  in btrfs_backref_unlock_node_buffer()
328 	if (node->eb) {  in btrfs_backref_drop_node_buffer()
330 		free_extent_buffer(node->eb);  in btrfs_backref_drop_node_buffer()
331 		node->eb = NULL;  in btrfs_backref_drop_node_buffer()
336  * Drop the backref node from cache without cleaning up its children
345 	ASSERT(list_empty(&node->upper));  in btrfs_backref_drop_node()
348 	list_del_init(&node->list);  in btrfs_backref_drop_node()
349 	list_del_init(&node->lower);  in btrfs_backref_drop_node()
350 	if (!RB_EMPTY_NODE(&node->rb_node))  in btrfs_backref_drop_node()
351 		rb_erase(&node->rb_node, &tree->rb_root);  in btrfs_backref_drop_node()
355 void btrfs_backref_cleanup_node(struct btrfs_backref_cache *cache,
358 void btrfs_backref_release_cache(struct btrfs_backref_cache *cache);
364 		    "Inconsistency in backref cache found at offset %llu",  in btrfs_backref_panic()
368 int btrfs_backref_add_tree_node(struct btrfs_backref_cache *cache,
374 int btrfs_backref_finish_upper_links(struct btrfs_backref_cache *cache,
377 void btrfs_backref_error_cleanup(struct btrfs_backref_cache *cache,