bcachefs: Fix journal deadlock

After we get a journal reservation, we need to use it - if we erorr out
of a transaction commit, we'll be eating into space in the journal and
if our transaction needs to make forward progress in order to reclaim
space in the journal, we'll deadlock.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/btree_update_leaf.c b/fs/bcachefs/btree_update_leaf.c
index 592f9516d4e7199dec30a89ccfc141f818365683..d3d86aa0ee95ff5a1de5bab7aeb23320d7154d57 100644 (file)
--- a/fs/bcachefs/btree_update_leaf.c
+++ b/fs/bcachefs/btree_update_leaf.c
@@ -426,6 +426,14 @@ bch2_trans_commit_write_locked(struct btree_trans *trans,
                fs_usage = bch2_fs_usage_scratch_get(c);
        }
 
+       /* Must be called under mark_lock: */
+       if (marking && trans->fs_usage_deltas &&
+           bch2_replicas_delta_list_apply(c, &fs_usage->u,
+                                          trans->fs_usage_deltas)) {
+               ret = BTREE_INSERT_NEED_MARK_REPLICAS;
+               goto err;
+       }
+
        /*
         * Don't get journal reservation until after we know insert will
         * succeed:
@@ -462,14 +470,6 @@ bch2_trans_commit_write_locked(struct btree_trans *trans,
                                i->k->k.version = MAX_VERSION;
        }
 
-       /* Must be called under mark_lock: */
-       if (marking && trans->fs_usage_deltas &&
-           bch2_replicas_delta_list_apply(c, &fs_usage->u,
-                                          trans->fs_usage_deltas)) {
-               ret = BTREE_INSERT_NEED_MARK_REPLICAS;
-               goto err;
-       }
-
        trans_for_each_update(trans, i)
                if (BTREE_NODE_TYPE_HAS_MEM_TRIGGERS & (1U << i->bkey_type))
                        bch2_mark_update(trans, i->iter, i->k,