From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from rcsinet15.oracle.com ([148.87.113.117]:29202 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755452Ab2JWPXg (ORCPT ); Tue, 23 Oct 2012 11:23:36 -0400 Message-ID: <5086B677.7050905@oracle.com> Date: Tue, 23 Oct 2012 23:23:35 +0800 From: Liu Bo MIME-Version: 1.0 To: Jan Schmidt CC: chris.mason@fusionio.com, linux-btrfs@vger.kernel.org Subject: Re: [PATCH 1/6] Btrfs: don't put removals from push_node_left into tree mod log twice References: <1351000527-24952-1-git-send-email-list.btrfs@jan-o-sch.net> <1351000527-24952-2-git-send-email-list.btrfs@jan-o-sch.net> In-Reply-To: <1351000527-24952-2-git-send-email-list.btrfs@jan-o-sch.net> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 10/23/2012 09:55 PM, Jan Schmidt wrote: > Independant of the check (push_items < src_items) tree_mod_log_eb_copy did > log the removal of the old data entries from the source buffer. Therefore, > we must not call tree_mod_log_eb_move if the check evaluates to true, as > that would log the removal twice, finally resulting in (rewinded) buffers > with wrong values for header_nritems. > Reviewed-by: Liu Bo Tested-by: Liu Bo thanks, liubo > Signed-off-by: Jan Schmidt > --- > fs/btrfs/ctree.c | 9 +++++++-- > 1 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index b334362..44a7e25 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -1225,6 +1225,8 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb, > free_extent_buffer(eb); > > __tree_mod_log_rewind(eb_rewin, time_seq, tm); > + WARN_ON(btrfs_header_nritems(eb_rewin) > > + BTRFS_NODEPTRS_PER_BLOCK(fs_info->fs_root)); > > return eb_rewin; > } > @@ -1280,6 +1282,7 @@ get_old_root(struct btrfs_root *root, u64 time_seq) > else > WARN_ON(btrfs_header_level(eb) != 0); > extent_buffer_get(eb); > + WARN_ON(btrfs_header_nritems(eb) > BTRFS_NODEPTRS_PER_BLOCK(root)); > > return eb; > } > @@ -2970,8 +2973,10 @@ static int push_node_left(struct btrfs_trans_handle *trans, > push_items * sizeof(struct btrfs_key_ptr)); > > if (push_items < src_nritems) { > - tree_mod_log_eb_move(root->fs_info, src, 0, push_items, > - src_nritems - push_items); > + /* > + * don't call tree_mod_log_eb_move here, key removal was already > + * fully logged by tree_mod_log_eb_copy above. > + */ > memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), > btrfs_node_key_ptr_offset(push_items), > (src_nritems - push_items) * >