From: Filipe Manana Date: Thu, 8 Jun 2023 10:27:45 +0000 (+0100) Subject: btrfs: abort transaction at update_ref_for_cow() when ref count is zero X-Git-Tag: block-6.5-2023-07-03~75^2~19 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=eced687e224eb3cc5a501cf53ad9291337c8dbc5;p=linux-block.git btrfs: abort transaction at update_ref_for_cow() when ref count is zero At update_ref_for_cow() we are calling btrfs_handle_fs_error() if we find that the extent buffer has an unexpected ref count of zero, however we can simply use btrfs_abort_transaction(), which achieves the same purposes: to turn the fs to error state, abort the current transaction and turn the fs to RO mode as well. Besides that, btrfs_abort_transaction() also prints a stack trace which makes it more useful. Also, as this is a very unexpected situation, indicating a serious corruption/inconsistency, tag the if branch as 'unlikely', set the error code to -EUCLEAN instead of -EROFS, and log an explicit message. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 00eea2925d1d..b643bd8656bf 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -421,9 +421,13 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, &refs, &flags); if (ret) return ret; - if (refs == 0) { - ret = -EROFS; - btrfs_handle_fs_error(fs_info, ret, NULL); + if (unlikely(refs == 0)) { + btrfs_crit(fs_info, + "found 0 references for tree block at bytenr %llu level %d root %llu", + buf->start, btrfs_header_level(buf), + btrfs_root_id(root)); + ret = -EUCLEAN; + btrfs_abort_transaction(trans, ret); return ret; } } else {