From patchwork Tue Dec 17 15:36:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 11297955 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 481D2138C for ; Tue, 17 Dec 2019 15:37:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 264B224672 for ; Tue, 17 Dec 2019 15:37:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20150623.gappssmtp.com header.i=@toxicpanda-com.20150623.gappssmtp.com header.b="YkEpmER4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728340AbfLQPhH (ORCPT ); Tue, 17 Dec 2019 10:37:07 -0500 Received: from mail-qv1-f68.google.com ([209.85.219.68]:38913 "EHLO mail-qv1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728266AbfLQPhH (ORCPT ); Tue, 17 Dec 2019 10:37:07 -0500 Received: by mail-qv1-f68.google.com with SMTP id y8so4330188qvk.6 for ; Tue, 17 Dec 2019 07:37:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=Em1wD5xLTxNTJX+7khPl9BkwuAHENTwYnPCkG17ZnDE=; b=YkEpmER4m1WYVwPxvaCGhI7ZScYG8fJaa/i5gbir+0gUHHd+x3Dc8DM+DUwsHeq6Kp jioBxcYY77BQvilA4c2QARzL2lRntSE2SuIffFeFmTmWweR05D6W/nusnu0FLra2V++k XUSO38Gm340st60kmUoxHYRZgfGg2RH8dnUC1R/714BLIt2tyBlAlAGmpgGt7v3wh+aC fAjiFUlI0dnKw91GHXRdurpFUTcUcSwBiwdT4hzXh32CjSo/iAbi+psMDwSNfzXgwsnf aqfSgMUAqFKO7ekqhfe3R+2fuBXr17VO3DSYkO3SrFO6AZ8TI5O3rUJuPRGJYzAxg3fP vayw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Em1wD5xLTxNTJX+7khPl9BkwuAHENTwYnPCkG17ZnDE=; b=MN15inPakGRB8TbPdnrw5XgxZRjj40jki6wxE0GB+BfIWe5SywzU/pZoLTohkaPOtc IHzWbozGgFZu5ZZaZ/InRA51Con2QFC5XB+GhOj1w++4VFwhYYla+hxGge+XuPurEKmN nkIJ7Kv13ciIwZ0/dgV/7I34zWwYHR3/RYNFjwNyRCUvX471h8944uhsoz9EJ11MMu/p AllgPr7mzKFDiXrXhgab0gpGFoHGOoj53aUuv+WQS33PbGo00KvuvFNg/ksUIoi9MB3U /2yVuF4uKKrVTOc1jMrWTTUuJzskC0qiGbCNBZfGkIYglQEI38fN+g2sk5yb5LOlvUVm i0gg== X-Gm-Message-State: APjAAAUfAB3GtNWxRX2BGRJdF8UsEnFrOb73JJR1osv5mC/80afuJpri UPCw9NG2suzUplay+Q2f7FFcTmsYuZU2SA== X-Google-Smtp-Source: APXvYqwwOIWHZjzMg+yqo01GktzE7ZP0UkX0DvtpKyUIkyCDsTIQrXkmTUz4dsB+9hydh/MxhYtyGg== X-Received: by 2002:a0c:d4aa:: with SMTP id u39mr5172130qvh.76.1576597025564; Tue, 17 Dec 2019 07:37:05 -0800 (PST) Received: from localhost ([107.15.81.208]) by smtp.gmail.com with ESMTPSA id d5sm7184003qke.130.2019.12.17.07.37.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Dec 2019 07:37:04 -0800 (PST) From: Josef Bacik To: linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 15/45] btrfs: grab a ref on the root in relink_extent_backref Date: Tue, 17 Dec 2019 10:36:05 -0500 Message-Id: <20191217153635.44733-16-josef@toxicpanda.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191217153635.44733-1-josef@toxicpanda.com> References: <20191217153635.44733-1-josef@toxicpanda.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org We're doing an arbitrary lookup on an fs_root, we need to hold a ref on that root. Signed-off-by: Josef Bacik --- fs/btrfs/inode.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 88f3d6eace7a..d46e3ec6ba30 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2711,8 +2711,12 @@ static noinline int relink_extent_backref(struct btrfs_path *path, return PTR_ERR(root); } + if (!btrfs_grab_fs_root(root)) + return 0; + if (btrfs_root_readonly(root)) { srcu_read_unlock(&fs_info->subvol_srcu, index); + btrfs_put_fs_root(root); return 0; } @@ -2722,6 +2726,7 @@ static noinline int relink_extent_backref(struct btrfs_path *path, key.offset = 0; inode = btrfs_iget(fs_info->sb, &key, root); + btrfs_put_fs_root(root); if (IS_ERR(inode)) { srcu_read_unlock(&fs_info->subvol_srcu, index); return 0;