19  * eb, the lockdep key is determined by the btrfs_root it belongs to and
20  * the level the eb occupies in the tree.
50 	DEFINE_LEVEL(stem, 1)						\
82 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, int level)  in btrfs_set_buffer_lockdep_class()  argument
93 	lockdep_set_class_and_name(&eb->lock, &ks->keys[level], ks->names[level]);  in btrfs_set_buffer_lockdep_class()
96 void btrfs_maybe_reset_lockdep_class(struct btrfs_root *root, struct extent_buffer *eb)  in btrfs_maybe_reset_lockdep_class()  argument
100 					       eb, btrfs_header_level(eb));  in btrfs_maybe_reset_lockdep_class()
123  * @eb:		the eb to be locked
129 void __btrfs_tree_read_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest)  in __btrfs_tree_read_lock()  argument
136 	down_read_nested(&eb->lock, nest);  in __btrfs_tree_read_lock()
137 	trace_btrfs_tree_read_lock(eb, start_ns);  in __btrfs_tree_read_lock()
140 void btrfs_tree_read_lock(struct extent_buffer *eb)  in btrfs_tree_read_lock()  argument
142 	__btrfs_tree_read_lock(eb, BTRFS_NESTING_NORMAL);  in btrfs_tree_read_lock()
148  * Return 1 if the rwlock has been taken, 0 otherwise
150 int btrfs_try_tree_read_lock(struct extent_buffer *eb)  in btrfs_try_tree_read_lock()  argument
152 	if (down_read_trylock(&eb->lock)) {  in btrfs_try_tree_read_lock()
153 		trace_btrfs_try_tree_read_lock(eb);  in btrfs_try_tree_read_lock()
154 		return 1;  in btrfs_try_tree_read_lock()
162  * Return 1 if the rwlock has been taken, 0 otherwise
164 int btrfs_try_tree_write_lock(struct extent_buffer *eb)  in btrfs_try_tree_write_lock()  argument
166 	if (down_write_trylock(&eb->lock)) {  in btrfs_try_tree_write_lock()
167 		eb->lock_owner = current->pid;  in btrfs_try_tree_write_lock()
168 		trace_btrfs_try_tree_write_lock(eb);  in btrfs_try_tree_write_lock()
169 		return 1;  in btrfs_try_tree_write_lock()
177 void btrfs_tree_read_unlock(struct extent_buffer *eb)  in btrfs_tree_read_unlock()  argument
179 	trace_btrfs_tree_read_unlock(eb);  in btrfs_tree_read_unlock()
180 	up_read(&eb->lock);  in btrfs_tree_read_unlock()
184  * __btrfs_tree_lock - lock eb for write
185  * @eb:		the eb to lock
188  * Returns with the eb->lock write locked.
190 void __btrfs_tree_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest)  in __btrfs_tree_lock()  argument
191 	__acquires(&eb->lock)  in __btrfs_tree_lock()
198 	down_write_nested(&eb->lock, nest);  in __btrfs_tree_lock()
199 	eb->lock_owner = current->pid;  in __btrfs_tree_lock()
200 	trace_btrfs_tree_lock(eb, start_ns);  in __btrfs_tree_lock()
203 void btrfs_tree_lock(struct extent_buffer *eb)  in btrfs_tree_lock()  argument
205 	__btrfs_tree_lock(eb, BTRFS_NESTING_NORMAL);  in btrfs_tree_lock()
211 void btrfs_tree_unlock(struct extent_buffer *eb)  in btrfs_tree_unlock()  argument
213 	trace_btrfs_tree_unlock(eb);  in btrfs_tree_unlock()
214 	eb->lock_owner = 0;  in btrfs_tree_unlock()
215 	up_write(&eb->lock);  in btrfs_tree_unlock()
252 	struct extent_buffer *eb;  in btrfs_lock_root_node()  local
254 	while (1) {  in btrfs_lock_root_node()
255 		eb = btrfs_root_node(root);  in btrfs_lock_root_node()
257 		btrfs_maybe_reset_lockdep_class(root, eb);  in btrfs_lock_root_node()
258 		btrfs_tree_lock(eb);  in btrfs_lock_root_node()
259 		if (eb == root->node)  in btrfs_lock_root_node()
261 		btrfs_tree_unlock(eb);  in btrfs_lock_root_node()
262 		free_extent_buffer(eb);  in btrfs_lock_root_node()
264 	return eb;  in btrfs_lock_root_node()
275 	struct extent_buffer *eb;  in btrfs_read_lock_root_node()  local
277 	while (1) {  in btrfs_read_lock_root_node()
278 		eb = btrfs_root_node(root);  in btrfs_read_lock_root_node()
280 		btrfs_maybe_reset_lockdep_class(root, eb);  in btrfs_read_lock_root_node()
281 		btrfs_tree_read_lock(eb);  in btrfs_read_lock_root_node()
282 		if (eb == root->node)  in btrfs_read_lock_root_node()
284 		btrfs_tree_read_unlock(eb);  in btrfs_read_lock_root_node()
285 		free_extent_buffer(eb);  in btrfs_read_lock_root_node()
287 	return eb;  in btrfs_read_lock_root_node()
299 	struct extent_buffer *eb;  in btrfs_try_read_lock_root_node()  local
301 	while (1) {  in btrfs_try_read_lock_root_node()
302 		eb = btrfs_root_node(root);  in btrfs_try_read_lock_root_node()
303 		if (!btrfs_try_tree_read_lock(eb)) {  in btrfs_try_read_lock_root_node()
304 			free_extent_buffer(eb);  in btrfs_try_read_lock_root_node()
307 		if (eb == root->node)  in btrfs_try_read_lock_root_node()
309 		btrfs_tree_read_unlock(eb);  in btrfs_try_read_lock_root_node()
310 		free_extent_buffer(eb);  in btrfs_try_read_lock_root_node()
312 	return eb;  in btrfs_try_read_lock_root_node()