18  * eb, the lockdep key is determined by the btrfs_root it belongs to and
19  * the level the eb occupies in the tree.
49 	DEFINE_LEVEL(stem, 1)						\
80 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, int level)  in btrfs_set_buffer_lockdep_class()  argument
91 	lockdep_set_class_and_name(&eb->lock, &ks->keys[level], ks->names[level]);  in btrfs_set_buffer_lockdep_class()
94 void btrfs_maybe_reset_lockdep_class(struct btrfs_root *root, struct extent_buffer *eb)  in btrfs_maybe_reset_lockdep_class()  argument
98 					       eb, btrfs_header_level(eb));  in btrfs_maybe_reset_lockdep_class()
121  * @eb:		the eb to be locked
127 void __btrfs_tree_read_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest)  in __btrfs_tree_read_lock()  argument
134 	down_read_nested(&eb->lock, nest);  in __btrfs_tree_read_lock()
135 	trace_btrfs_tree_read_lock(eb, start_ns);  in __btrfs_tree_read_lock()
138 void btrfs_tree_read_lock(struct extent_buffer *eb)  in btrfs_tree_read_lock()  argument
140 	__btrfs_tree_read_lock(eb, BTRFS_NESTING_NORMAL);  in btrfs_tree_read_lock()
146  * Return 1 if the rwlock has been taken, 0 otherwise
148 int btrfs_try_tree_read_lock(struct extent_buffer *eb)  in btrfs_try_tree_read_lock()  argument
150 	if (down_read_trylock(&eb->lock)) {  in btrfs_try_tree_read_lock()
151 		trace_btrfs_try_tree_read_lock(eb);  in btrfs_try_tree_read_lock()
152 		return 1;  in btrfs_try_tree_read_lock()
160  * Return 1 if the rwlock has been taken, 0 otherwise
162 int btrfs_try_tree_write_lock(struct extent_buffer *eb)  in btrfs_try_tree_write_lock()  argument
164 	if (down_write_trylock(&eb->lock)) {  in btrfs_try_tree_write_lock()
165 		eb->lock_owner = current->pid;  in btrfs_try_tree_write_lock()
166 		trace_btrfs_try_tree_write_lock(eb);  in btrfs_try_tree_write_lock()
167 		return 1;  in btrfs_try_tree_write_lock()
175 void btrfs_tree_read_unlock(struct extent_buffer *eb)  in btrfs_tree_read_unlock()  argument
177 	trace_btrfs_tree_read_unlock(eb);  in btrfs_tree_read_unlock()
178 	up_read(&eb->lock);  in btrfs_tree_read_unlock()
182  * __btrfs_tree_lock - lock eb for write
183  * @eb:		the eb to lock
186  * Returns with the eb->lock write locked.
188 void __btrfs_tree_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest)  in __btrfs_tree_lock()  argument
189 	__acquires(&eb->lock)  in __btrfs_tree_lock()
196 	down_write_nested(&eb->lock, nest);  in __btrfs_tree_lock()
197 	eb->lock_owner = current->pid;  in __btrfs_tree_lock()
198 	trace_btrfs_tree_lock(eb, start_ns);  in __btrfs_tree_lock()
201 void btrfs_tree_lock(struct extent_buffer *eb)  in btrfs_tree_lock()  argument
203 	__btrfs_tree_lock(eb, BTRFS_NESTING_NORMAL);  in btrfs_tree_lock()
209 void btrfs_tree_unlock(struct extent_buffer *eb)  in btrfs_tree_unlock()  argument
211 	trace_btrfs_tree_unlock(eb);  in btrfs_tree_unlock()
212 	eb->lock_owner = 0;  in btrfs_tree_unlock()
213 	up_write(&eb->lock);  in btrfs_tree_unlock()
250 	struct extent_buffer *eb;  in btrfs_lock_root_node()  local
252 	while (1) {  in btrfs_lock_root_node()
253 		eb = btrfs_root_node(root);  in btrfs_lock_root_node()
255 		btrfs_maybe_reset_lockdep_class(root, eb);  in btrfs_lock_root_node()
256 		btrfs_tree_lock(eb);  in btrfs_lock_root_node()
257 		if (eb == root->node)  in btrfs_lock_root_node()
259 		btrfs_tree_unlock(eb);  in btrfs_lock_root_node()
260 		free_extent_buffer(eb);  in btrfs_lock_root_node()
262 	return eb;  in btrfs_lock_root_node()
273 	struct extent_buffer *eb;  in btrfs_read_lock_root_node()  local
275 	while (1) {  in btrfs_read_lock_root_node()
276 		eb = btrfs_root_node(root);  in btrfs_read_lock_root_node()
278 		btrfs_maybe_reset_lockdep_class(root, eb);  in btrfs_read_lock_root_node()
279 		btrfs_tree_read_lock(eb);  in btrfs_read_lock_root_node()
280 		if (eb == root->node)  in btrfs_read_lock_root_node()
282 		btrfs_tree_read_unlock(eb);  in btrfs_read_lock_root_node()
283 		free_extent_buffer(eb);  in btrfs_read_lock_root_node()
285 	return eb;  in btrfs_read_lock_root_node()
297 	struct extent_buffer *eb;  in btrfs_try_read_lock_root_node()  local
299 	while (1) {  in btrfs_try_read_lock_root_node()
300 		eb = btrfs_root_node(root);  in btrfs_try_read_lock_root_node()
301 		if (!btrfs_try_tree_read_lock(eb)) {  in btrfs_try_read_lock_root_node()
302 			free_extent_buffer(eb);  in btrfs_try_read_lock_root_node()
305 		if (eb == root->node)  in btrfs_try_read_lock_root_node()
307 		btrfs_tree_read_unlock(eb);  in btrfs_try_read_lock_root_node()
308 		free_extent_buffer(eb);  in btrfs_try_read_lock_root_node()
310 	return eb;  in btrfs_try_read_lock_root_node()