When a fresh transaction begins, the tree mod log must be clean. Users of the tree modification log must ensure they never span across transaction boundaries. We reset the sequence to 0 in this safe situation to make absolutely sure overflow can't happen. Signed-off-by: Jan Schmidt <list.btrfs@xxxxxxxxxxxxx> --- fs/btrfs/transaction.c | 9 +++++++++ 1 files changed, 9 insertions(+), 0 deletions(-) diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index eb2bd82..3f50cba 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -122,6 +122,15 @@ loop: cur_trans->delayed_refs.flushing = 0; cur_trans->delayed_refs.run_delayed_start = 0; cur_trans->delayed_refs.seq = 1; + + /* + * although the tree mod log is per file system and not per transaction, + * the log must never go across transaction boundaries. + */ + BUG_ON(!list_empty(&fs_info->tree_mod_seq_list)); + BUG_ON(!RB_EMPTY_ROOT(&fs_info->tree_mod_log)); + atomic_set(&fs_info->tree_mod_seq, 0); + init_waitqueue_head(&cur_trans->delayed_refs.seq_wait); spin_lock_init(&cur_trans->commit_lock); spin_lock_init(&cur_trans->delayed_refs.lock); -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
