From patchwork Wed Aug 29 04:11:52 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miao Xie X-Patchwork-Id: 1383501 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 13D84DFFCF for ; Wed, 29 Aug 2012 04:12:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751268Ab2H2EMV (ORCPT ); Wed, 29 Aug 2012 00:12:21 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:20181 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750845Ab2H2EMS (ORCPT ); Wed, 29 Aug 2012 00:12:18 -0400 X-IronPort-AV: E=Sophos;i="4.80,332,1344182400"; d="scan'208";a="5743594" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 29 Aug 2012 12:11:08 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id q7T4CHCn031814 for ; Wed, 29 Aug 2012 12:12:17 +0800 Received: from [10.167.225.199] ([10.167.225.199]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2012082912120560-537232 ; Wed, 29 Aug 2012 12:12:05 +0800 Message-ID: <503D9688.4040700@cn.fujitsu.com> Date: Wed, 29 Aug 2012 12:11:52 +0800 From: Miao Xie Reply-To: miaox@cn.fujitsu.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Linux Btrfs Subject: [PATCH V3 1/7 RESEND] Btrfs: fix error path in create_pending_snapshot() X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/08/29 12:12:06, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/08/29 12:12:06, Serialize complete at 2012/08/29 12:12:06 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This patch fixes the following problem: - If we failed to deal with the delayed dir items, we should abort transaction, just as its comment said. Fix it. - If root reference or root back reference insertion failed, we should abort transaction. Fix it. - Fix the double free problem of pending->inherit. - Do not restore the trans->rsv if we doesn't change it. - make the error path more clearly. Signed-off-by: Miao Xie --- Changelog v2 -> v3: - rebase on the latest for-linus branch - fix double free problem of pending->inherit Changelog v1 -> v2: - fix double dput() when aborting transaction. --- fs/btrfs/transaction.c | 40 +++++++++++++++++----------------------- 1 files changed, 17 insertions(+), 23 deletions(-) diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 3ee8d58..b259d22f2 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -962,18 +962,16 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, u64 root_flags; uuid_le new_uuid; - rsv = trans->block_rsv; - new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); if (!new_root_item) { ret = pending->error = -ENOMEM; - goto fail; + goto root_item_alloc_fail; } ret = btrfs_find_free_objectid(tree_root, &objectid); if (ret) { pending->error = ret; - goto fail; + goto no_free_objectid; } btrfs_reloc_pre_snapshot(trans, pending, &to_reserve); @@ -983,22 +981,22 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, to_reserve); if (ret) { pending->error = ret; - goto fail; + goto no_free_objectid; } } ret = btrfs_qgroup_inherit(trans, fs_info, root->root_key.objectid, objectid, pending->inherit); - kfree(pending->inherit); if (ret) { pending->error = ret; - goto fail; + goto no_free_objectid; } key.objectid = objectid; key.offset = (u64)-1; key.type = BTRFS_ROOT_ITEM_KEY; + rsv = trans->block_rsv; trans->block_rsv = &pending->block_rsv; dentry = pending->dentry; @@ -1018,10 +1016,9 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, BTRFS_FT_DIR, index); if (ret == -EEXIST) { pending->error = -EEXIST; - dput(parent); goto fail; } else if (ret) { - goto abort_trans_dput; + goto abort_trans; } btrfs_i_size_write(parent_inode, parent_inode->i_size + @@ -1029,7 +1026,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME; ret = btrfs_update_inode(trans, parent_root, parent_inode); if (ret) - goto abort_trans_dput; + goto abort_trans; /* * pull in the delayed directory update @@ -1038,10 +1035,8 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, * snapshot */ ret = btrfs_run_delayed_items(trans, root); - if (ret) { /* Transaction aborted */ - dput(parent); - goto fail; - } + if (ret) /* Transaction aborted */ + goto abort_trans; record_root_in_trans(trans, root); btrfs_set_root_last_snapshot(&root->root_item, trans->transid); @@ -1074,7 +1069,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, if (ret) { btrfs_tree_unlock(old); free_extent_buffer(old); - goto abort_trans_dput; + goto abort_trans; } btrfs_set_lock_blocking(old); @@ -1084,7 +1079,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, btrfs_tree_unlock(old); free_extent_buffer(old); if (ret) - goto abort_trans_dput; + goto abort_trans; /* see comments in should_cow_block() */ root->force_cow = 1; @@ -1097,7 +1092,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, btrfs_tree_unlock(tmp); free_extent_buffer(tmp); if (ret) - goto abort_trans_dput; + goto abort_trans; /* * insert root back/forward references @@ -1106,9 +1101,8 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, parent_root->root_key.objectid, btrfs_ino(parent_inode), index, dentry->d_name.name, dentry->d_name.len); - dput(parent); if (ret) - goto fail; + goto abort_trans; key.offset = (u64)-1; pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key); @@ -1120,15 +1114,15 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, ret = btrfs_reloc_post_snapshot(trans, pending); if (ret) goto abort_trans; - ret = 0; fail: - kfree(new_root_item); + dput(parent); trans->block_rsv = rsv; +no_free_objectid: + kfree(new_root_item); +root_item_alloc_fail: btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1); return ret; -abort_trans_dput: - dput(parent); abort_trans: btrfs_abort_transaction(trans, root, ret); goto fail;