Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

[firefly-linux-kernel-4.4.55.git] / fs / btrfs / delayed-ref.h

diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index 25589456d1c9ecabaaef57d78eecc5a92645513d..c9d703693df0b91e4c01a9181f93d2ab64572dcf 100644 (file)
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -139,26 +139,6 @@ struct btrfs_delayed_ref_root {
        int flushing;
 
        u64 run_delayed_start;
-
-       /*
-        * seq number of delayed refs. We need to know if a backref was being
-        * added before the currently processed ref or afterwards.
-        */
-       u64 seq;
-
-       /*
-        * seq_list holds a list of all seq numbers that are currently being
-        * added to the list. While walking backrefs (btrfs_find_all_roots,
-        * qgroups), which might take some time, no newer ref must be processed,
-        * as it might influence the outcome of the walk.
-        */
-       struct list_head seq_head;
-
-       /*
-        * when the only refs we have in the list must not be processed, we want
-        * to wait for more refs to show up or for the end of backref walking.
-        */
-       wait_queue_head_t seq_wait;
 };
 
 static inline void btrfs_put_delayed_ref(struct btrfs_delayed_ref_node *ref)
@@ -187,6 +167,10 @@ int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info,
                                struct btrfs_trans_handle *trans,
                                u64 bytenr, u64 num_bytes,
                                struct btrfs_delayed_extent_op *extent_op);
+void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
+                             struct btrfs_fs_info *fs_info,
+                             struct btrfs_delayed_ref_root *delayed_refs,
+                             struct btrfs_delayed_ref_head *head);
 
 struct btrfs_delayed_ref_head *
 btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr);
@@ -195,34 +179,28 @@ int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans,
 int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans,
                           struct list_head *cluster, u64 search_start);
 
-static inline u64 inc_delayed_seq(struct btrfs_delayed_ref_root *delayed_refs)
-{
-       assert_spin_locked(&delayed_refs->lock);
-       ++delayed_refs->seq;
-       return delayed_refs->seq;
-}
+int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info,
+                           struct btrfs_delayed_ref_root *delayed_refs,
+                           u64 seq);
 
-static inline void
-btrfs_get_delayed_seq(struct btrfs_delayed_ref_root *delayed_refs,
-                     struct seq_list *elem)
+/*
+ * delayed refs with a ref_seq > 0 must be held back during backref walking.
+ * this only applies to items in one of the fs-trees. for_cow items never need
+ * to be held back, so they won't get a ref_seq number.
+ */
+static inline int need_ref_seq(int for_cow, u64 rootid)
 {
-       assert_spin_locked(&delayed_refs->lock);
-       elem->seq = delayed_refs->seq;
-       list_add_tail(&elem->list, &delayed_refs->seq_head);
-}
+       if (for_cow)
+               return 0;
 
-static inline void
-btrfs_put_delayed_seq(struct btrfs_delayed_ref_root *delayed_refs,
-                     struct seq_list *elem)
-{
-       spin_lock(&delayed_refs->lock);
-       list_del(&elem->list);
-       wake_up(&delayed_refs->seq_wait);
-       spin_unlock(&delayed_refs->lock);
-}
+       if (rootid == BTRFS_FS_TREE_OBJECTID)
+               return 1;
 
-int btrfs_check_delayed_seq(struct btrfs_delayed_ref_root *delayed_refs,
-                           u64 seq);
+       if ((s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID)
+               return 1;
+
+       return 0;
+}
 
 /*
  * a node might live in a head or a regular ref, this lets you