From patchwork Mon Dec 15 16:04:42 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Filipe Manana X-Patchwork-Id: 5495491 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 9B848BEEA8 for ; Mon, 15 Dec 2014 16:07:33 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 22897209E5 for ; Mon, 15 Dec 2014 16:07:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 24FEE2041C for ; Mon, 15 Dec 2014 16:07:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751333AbaLOQHX (ORCPT ); Mon, 15 Dec 2014 11:07:23 -0500 Received: from victor.provo.novell.com ([137.65.250.26]:38147 "EHLO prv3-mh.provo.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750765AbaLOQHW (ORCPT ); Mon, 15 Dec 2014 11:07:22 -0500 Received: from debian3.lan (prv-ext-foundry1int.gns.novell.com [137.65.251.240]) by prv3-mh.provo.novell.com with ESMTP (NOT encrypted); Mon, 15 Dec 2014 09:07:09 -0700 From: Filipe Manana To: linux-btrfs@vger.kernel.org Cc: Filipe Manana Subject: [PATCH] Btrfs: correctly get tree level in tree_backref_for_extent Date: Mon, 15 Dec 2014 16:04:42 +0000 Message-Id: <1418659482-11734-1-git-send-email-fdmanana@suse.com> X-Mailer: git-send-email 2.1.3 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If we are using skinny metadata, the block's tree level is in the offset of the key and not in a btrfs_tree_block_info structure following the extent item (it doesn't exist). Therefore fix it. Besides returning the correct level in the tree, this also prevents reading past the leaf's end in the case where the extent item is the last item in the leaf (eb) and it has only 1 inline reference - this is because sizeof(struct btrfs_tree_block_info) is greater than sizeof(struct btrfs_extent_inline_ref). Got it while running a scrub which produced the following warning: BTRFS: checksum error at logical 42123264 on dev /dev/sde, sector 15840: metadata node (level 24) in tree 5 Signed-off-by: Filipe Manana Reviewed-by: Satoru Takeuchi --- fs/btrfs/backref.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 2d3e32e..8729cf6 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1552,7 +1552,6 @@ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, { int ret; int type; - struct btrfs_tree_block_info *info; struct btrfs_extent_inline_ref *eiref; if (*ptr == (unsigned long)-1) @@ -1573,9 +1572,17 @@ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, } /* we can treat both ref types equally here */ - info = (struct btrfs_tree_block_info *)(ei + 1); *out_root = btrfs_extent_inline_ref_offset(eb, eiref); - *out_level = btrfs_tree_block_level(eb, info); + + if (key->type == BTRFS_EXTENT_ITEM_KEY) { + struct btrfs_tree_block_info *info; + + info = (struct btrfs_tree_block_info *)(ei + 1); + *out_level = btrfs_tree_block_level(eb, info); + } else { + ASSERT(key->type == BTRFS_METADATA_ITEM_KEY); + *out_level = (u8)key->offset; + } if (ret == 1) *ptr = (unsigned long)-1;