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)						\
83 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, int level)  in btrfs_set_buffer_lockdep_class()  argument
94 	lockdep_set_class_and_name(&eb->lock, &ks->keys[level], ks->names[level]);  in btrfs_set_buffer_lockdep_class()
97 void btrfs_maybe_reset_lockdep_class(struct btrfs_root *root, struct extent_buffer *eb)  in btrfs_maybe_reset_lockdep_class()  argument
101 					       eb, btrfs_header_level(eb));  in btrfs_maybe_reset_lockdep_class()
107 static void btrfs_set_eb_lock_owner(struct extent_buffer *eb, pid_t owner)  in btrfs_set_eb_lock_owner()  argument
109 	eb->lock_owner = owner;  in btrfs_set_eb_lock_owner()
112 static void btrfs_set_eb_lock_owner(struct extent_buffer *eb, pid_t owner) { }  in btrfs_set_eb_lock_owner()  argument
133  * @eb:		the eb to be locked
139 void btrfs_tree_read_lock_nested(struct extent_buffer *eb, enum btrfs_lock_nesting nest)  in btrfs_tree_read_lock_nested()  argument
146 	down_read_nested(&eb->lock, nest);  in btrfs_tree_read_lock_nested()
147 	trace_btrfs_tree_read_lock(eb, start_ns);  in btrfs_tree_read_lock_nested()
153  * Return 1 if the rwlock has been taken, 0 otherwise
155 int btrfs_try_tree_read_lock(struct extent_buffer *eb)  in btrfs_try_tree_read_lock()  argument
157 	if (down_read_trylock(&eb->lock)) {  in btrfs_try_tree_read_lock()
158 		trace_btrfs_try_tree_read_lock(eb);  in btrfs_try_tree_read_lock()
159 		return 1;  in btrfs_try_tree_read_lock()
167  * Return 1 if the rwlock has been taken, 0 otherwise
169 int btrfs_try_tree_write_lock(struct extent_buffer *eb)  in btrfs_try_tree_write_lock()  argument
171 	if (down_write_trylock(&eb->lock)) {  in btrfs_try_tree_write_lock()
172 		btrfs_set_eb_lock_owner(eb, current->pid);  in btrfs_try_tree_write_lock()
173 		trace_btrfs_try_tree_write_lock(eb);  in btrfs_try_tree_write_lock()
174 		return 1;  in btrfs_try_tree_write_lock()
182 void btrfs_tree_read_unlock(struct extent_buffer *eb)  in btrfs_tree_read_unlock()  argument
184 	trace_btrfs_tree_read_unlock(eb);  in btrfs_tree_read_unlock()
185 	up_read(&eb->lock);  in btrfs_tree_read_unlock()
189  * Lock eb for write.
191  * @eb:		the eb to lock
194  * Returns with the eb->lock write locked.
196 void btrfs_tree_lock_nested(struct extent_buffer *eb, enum btrfs_lock_nesting nest)  in btrfs_tree_lock_nested()  argument
197 	__acquires(&eb->lock)  in btrfs_tree_lock_nested()
204 	down_write_nested(&eb->lock, nest);  in btrfs_tree_lock_nested()
205 	btrfs_set_eb_lock_owner(eb, current->pid);  in btrfs_tree_lock_nested()
206 	trace_btrfs_tree_lock(eb, start_ns);  in btrfs_tree_lock_nested()
212 void btrfs_tree_unlock(struct extent_buffer *eb)  in btrfs_tree_unlock()  argument
214 	trace_btrfs_tree_unlock(eb);  in btrfs_tree_unlock()
215 	btrfs_set_eb_lock_owner(eb, 0);  in btrfs_tree_unlock()
216 	up_write(&eb->lock);  in btrfs_tree_unlock()
253 	struct extent_buffer *eb;  in btrfs_lock_root_node()  local
255 	while (1) {  in btrfs_lock_root_node()
256 		eb = btrfs_root_node(root);  in btrfs_lock_root_node()
258 		btrfs_maybe_reset_lockdep_class(root, eb);  in btrfs_lock_root_node()
259 		btrfs_tree_lock(eb);  in btrfs_lock_root_node()
260 		if (eb == root->node)  in btrfs_lock_root_node()
262 		btrfs_tree_unlock(eb);  in btrfs_lock_root_node()
263 		free_extent_buffer(eb);  in btrfs_lock_root_node()
265 	return eb;  in btrfs_lock_root_node()
276 	struct extent_buffer *eb;  in btrfs_read_lock_root_node()  local
278 	while (1) {  in btrfs_read_lock_root_node()
279 		eb = btrfs_root_node(root);  in btrfs_read_lock_root_node()
281 		btrfs_maybe_reset_lockdep_class(root, eb);  in btrfs_read_lock_root_node()
282 		btrfs_tree_read_lock(eb);  in btrfs_read_lock_root_node()
283 		if (eb == root->node)  in btrfs_read_lock_root_node()
285 		btrfs_tree_read_unlock(eb);  in btrfs_read_lock_root_node()
286 		free_extent_buffer(eb);  in btrfs_read_lock_root_node()
288 	return eb;  in btrfs_read_lock_root_node()
300 	struct extent_buffer *eb;  in btrfs_try_read_lock_root_node()  local
302 	while (1) {  in btrfs_try_read_lock_root_node()
303 		eb = btrfs_root_node(root);  in btrfs_try_read_lock_root_node()
304 		if (!btrfs_try_tree_read_lock(eb)) {  in btrfs_try_read_lock_root_node()
305 			free_extent_buffer(eb);  in btrfs_try_read_lock_root_node()
308 		if (eb == root->node)  in btrfs_try_read_lock_root_node()
310 		btrfs_tree_read_unlock(eb);  in btrfs_try_read_lock_root_node()
311 		free_extent_buffer(eb);  in btrfs_try_read_lock_root_node()
313 	return eb;  in btrfs_try_read_lock_root_node()