From de6bc7f59896e888d388a2b469807a4d4b4ab55e Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Wed, 15 Dec 2021 12:20:01 +0000 Subject: [PATCH] btrfs: stop trying to log subdirectories created in past transactions When logging a directory we are trying to log subdirectories that were changed in the current transaction and created in a past transaction. This type of behaviour was introduced by commit 2f2ff0ee5e4303 ("Btrfs: fix metadata inconsistencies after directory fsync"), to fix some metadata inconsistencies that in the meanwhile no longer need this behaviour due to numerous other changes that happened throughout the years. This behaviour, besides not needed anymore, it's also undesirable because: 1) It's not reliable because it's only triggered for the directories of dentries (dir items) that happen to be present on a leaf that was changed in the current transaction. If a dentry that points to a directory resides on a leaf that was not changed in the current transaction, then it's not logged, as at log_dir_items() and log_new_dir_dentries() we use btrfs_search_forward(); 2) It's not required by posix or any standard, it's undefined territory. The only way to guarantee a subdirectory is logged, it to explicitly fsync it; Making the behaviour guaranteed would require scanning all directory items, check which point to a directory, and then fsync each subdirectory which was modified in the current transaction. This could be very expensive for large directories with many subdirectories and/or large subdirectories. So remove that obsolete logic. Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/tree-log.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index a367d62572c1..a0364f16e790 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -6012,8 +6012,7 @@ again: di = btrfs_item_ptr(leaf, i, struct btrfs_dir_item); type = btrfs_dir_type(leaf, di); - if (btrfs_dir_transid(leaf, di) < trans->transid && - type != BTRFS_FT_DIR) + if (btrfs_dir_transid(leaf, di) < trans->transid) continue; btrfs_dir_item_key_to_cpu(leaf, di, &di_key); if (di_key.type == BTRFS_ROOT_ITEM_KEY)