31  * extent_map_tree_init - initialize extent map tree
32  * @tree:		tree to initialize
34  * Initialize the extent tree @tree.  Should be called for each new inode
37 void extent_map_tree_init(struct extent_map_tree *tree)  in extent_map_tree_init()  argument
39 	tree->map = RB_ROOT_CACHED;  in extent_map_tree_init()
40 	INIT_LIST_HEAD(&tree->modified_extents);  in extent_map_tree_init()
41 	rwlock_init(&tree->lock);  in extent_map_tree_init()
140  * search through the tree for an extent_map with a given offset.  If
239 static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)  in try_merge_map()  argument
245 	 * We can't modify an extent map that is in the tree and that is being  in try_merge_map()
248 	 * the tree and 1 for this task (which is unpinning the extent map or  in try_merge_map()
270 			rb_erase_cached(&merge->rb_node, &tree->map);  in try_merge_map()
282 		rb_erase_cached(&merge->rb_node, &tree->map);  in try_merge_map()
293  * @tree:	tree to unpin the extent in
302 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,  in unpin_extent_cache()  argument
309 	write_lock(&tree->lock);  in unpin_extent_cache()
310 	em = lookup_extent_mapping(tree, start, len);  in unpin_extent_cache()
327 	try_merge_map(tree, em);  in unpin_extent_cache()
336 	write_unlock(&tree->lock);  in unpin_extent_cache()
341 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em)  in clear_em_logging()  argument
343 	lockdep_assert_held_write(&tree->lock);  in clear_em_logging()
347 		try_merge_map(tree, em);  in clear_em_logging()
350 static inline void setup_extent_mapping(struct extent_map_tree *tree,  in setup_extent_mapping()  argument
359 		list_move(&em->list, &tree->modified_extents);  in setup_extent_mapping()
361 		try_merge_map(tree, em);  in setup_extent_mapping()
396  * Add new extent map to the extent tree
398  * @tree:	tree to insert new map in
403  * Insert @em into @tree or perform a simple forward/backward merge with
405  * into the tree directly, with an additional reference taken, or a
408 int add_extent_mapping(struct extent_map_tree *tree,  in add_extent_mapping()  argument
413 	lockdep_assert_held_write(&tree->lock);  in add_extent_mapping()
415 	ret = tree_insert(&tree->map, em);  in add_extent_mapping()
419 	setup_extent_mapping(tree, em, modified);  in add_extent_mapping()
429 __lookup_extent_mapping(struct extent_map_tree *tree,  in __lookup_extent_mapping()  argument
437 	rb_node = __tree_search(&tree->map.rb_root, start, &prev_or_next);  in __lookup_extent_mapping()
456  * @tree:	tree to lookup in
460  * Find and return the first extent_map struct in @tree that intersects the
461  * [start, len] range.  There may be additional objects in the tree that
465 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,  in lookup_extent_mapping()  argument
468 	return __lookup_extent_mapping(tree, start, len, 1);  in lookup_extent_mapping()
473  * @tree:	tree to lookup in
477  * Find and return the first extent_map struct in @tree that intersects the
482 struct extent_map *search_extent_mapping(struct extent_map_tree *tree,  in search_extent_mapping()  argument
485 	return __lookup_extent_mapping(tree, start, len, 0);  in search_extent_mapping()
489  * remove_extent_mapping - removes an extent_map from the extent tree
490  * @tree:	extent tree to remove from
493  * Removes @em from @tree.  No reference counts are dropped, and no checks
496 void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)  in remove_extent_mapping()  argument
498 	lockdep_assert_held_write(&tree->lock);  in remove_extent_mapping()
501 	rb_erase_cached(&em->rb_node, &tree->map);  in remove_extent_mapping()
509 void replace_extent_mapping(struct extent_map_tree *tree,  in replace_extent_mapping()  argument
514 	lockdep_assert_held_write(&tree->lock);  in replace_extent_mapping()
520 	rb_replace_node_cached(&cur->rb_node, &new->rb_node, &tree->map);  in replace_extent_mapping()
523 	setup_extent_mapping(tree, new, modified);  in replace_extent_mapping()
547  * Helper for btrfs_get_extent.  Given an existing extent in the tree,
550  * the best fitted new extent into the tree.
592  * @em_tree:  extent tree into which we want to insert the extent mapping
617 	/* it is possible that someone inserted the extent into the tree  in btrfs_add_extent_mapping()
619 	 * an overlapping map exists in the tree  in btrfs_add_extent_mapping()
666  * Drop all extent maps from a tree in the fastest possible way, rescheduling
667  * if needed. This avoids searching the tree, from the root down to the first
670 static void drop_all_extent_maps_fast(struct extent_map_tree *tree)  in drop_all_extent_maps_fast()  argument
672 	write_lock(&tree->lock);  in drop_all_extent_maps_fast()
673 	while (!RB_EMPTY_ROOT(&tree->map.rb_root)) {  in drop_all_extent_maps_fast()
677 		node = rb_first_cached(&tree->map);  in drop_all_extent_maps_fast()
681 		remove_extent_mapping(tree, em);  in drop_all_extent_maps_fast()
683 		cond_resched_rwlock_write(&tree->lock);  in drop_all_extent_maps_fast()
685 	write_unlock(&tree->lock);  in drop_all_extent_maps_fast()
700  * tree before calling this function.
870 			 * If the extent map is still in the tree it means that  in btrfs_drop_extent_map_range()
883 			 * load it again from the subvolume tree's file extent  in btrfs_drop_extent_map_range()
897 		 * Once for the tree reference (we replaced or removed the  in btrfs_drop_extent_map_range()
898 		 * extent map from the tree).  in btrfs_drop_extent_map_range()
915  * Replace a range in the inode's extent map tree with a new extent map.
918  * @new_em:     The new extent map to add to the inode's extent map tree.
922  * Drops all the extent maps in the inode's extent map tree that intersect the
923  * range of the new extent map and adds the new extent map to the tree.
925  * tree before calling this function.
932 	struct extent_map_tree *tree = &inode->extent_tree;  in btrfs_replace_extent_map_range()  local
939 	 * tree, but getting -EEXIST when adding the new extent map can still  in btrfs_replace_extent_map_range()
947 		write_lock(&tree->lock);  in btrfs_replace_extent_map_range()
948 		ret = add_extent_mapping(tree, new_em, modified);  in btrfs_replace_extent_map_range()
949 		write_unlock(&tree->lock);  in btrfs_replace_extent_map_range()