From patchwork Tue Sep 1 00:31:41 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 7109211 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id CC9779F32B for ; Wed, 2 Sep 2015 07:52:03 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D569F20632 for ; Wed, 2 Sep 2015 07:52:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D493520631 for ; Wed, 2 Sep 2015 07:52:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753083AbbIBHv6 (ORCPT ); Wed, 2 Sep 2015 03:51:58 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:18969 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752466AbbIBHvX (ORCPT ); Wed, 2 Sep 2015 03:51:23 -0400 Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 01 Sep 2015 08:32:42 +0800 Received: from localhost.localdomain (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id t810XlIe023763 for ; Tue, 1 Sep 2015 08:33:50 +0800 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH RFC 01/14] btrfs: qgroup: New function declaration for new reserve implement Date: Tue, 1 Sep 2015 08:31:41 +0800 Message-Id: <1441067515-21105-2-git-send-email-quwenruo@cn.fujitsu.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1441067515-21105-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1441067515-21105-1-git-send-email-quwenruo@cn.fujitsu.com> 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 Add new structures and functions for new qgroup reserve implement dirty phase. Which will focus on avoiding over-reserve as in that case, which means for already reserved dirty space range, we won't reserve space again. This patch adds the needed structure declaration and comments. Signed-off-by: Qu Wenruo --- fs/btrfs/btrfs_inode.h | 4 ++++ fs/btrfs/qgroup.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/qgroup.h | 3 +++ 3 files changed, 65 insertions(+) diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 0ef5cc1..6d799b8 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -24,6 +24,7 @@ #include "extent_io.h" #include "ordered-data.h" #include "delayed-inode.h" +#include "qgroup.h" /* * ordered_data_close is set by truncate when a file that used @@ -193,6 +194,9 @@ struct btrfs_inode { struct timespec i_otime; struct inode vfs_inode; + + /* qgroup dirty map for data space reserve */ + struct btrfs_qgroup_data_rsv_map *qgroup_rsv_map; }; extern unsigned char btrfs_filetype_table[]; diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 1667567..640106a 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -91,6 +91,64 @@ struct btrfs_qgroup { u64 new_refcnt; }; +/* + * Record one range of reserved space. + */ +struct data_rsv_range { + struct rb_node node; + u64 start; + u64 len; +}; + +/* + * Record per inode reserved range. + * This is mainly used to resolve reserved space leaking problem. + * One of the cause is the mismatch with reserve and free. + * + * New qgroup will handle reserve in two phase. + * 1) Dirty phase. + * Pages are just marked dirty, but not written to disk. + * 2) Flushed phase + * Pages are written to disk, but transaction is not committed yet. + * + * At Diryt phase, we only need to focus on avoiding over-reserve. + * + * The idea is like below. + * 1) Write [0,8K) + * 0 4K 8K 12K 16K + * |////////////| + * Reserve +8K, total reserved: 8K + * + * 2) Write [0,4K) + * 0 4K 8K 12K 16K + * |////////////| + * Reserve 0, total reserved 8K + * + * 3) Write [12K,16K) + * 0 4K 8K 12K 16K + * |////////////| |///////| + * Reserve +4K, tocal reserved 12K + * + * 4) Flush [0,8K) + * Can happen without commit transaction, like fallocate will trigger the + * write. + * 0 4K 8K 12K 16K + * |///////| + * Reserve 0, tocal reserved 12K + * As the extent is written to disk, not dirty any longer, the range get + * removed. + * But as its delayed_refs is not run, its reserved space will not be freed. + * And things continue to Flushed phase. + * + * By this method, we can avoid over-reserve, which will lead to reserved + * space leak. + */ +struct btrfs_qgroup_data_rsv_map { + struct rb_root root; + u64 reserved; + spinlock_t lock; +}; + static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq, int mod) { diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h index 6387dcf..2f863a4 100644 --- a/fs/btrfs/qgroup.h +++ b/fs/btrfs/qgroup.h @@ -33,6 +33,9 @@ struct btrfs_qgroup_extent_record { struct ulist *old_roots; }; +/* For per-inode dirty range reserve */ +struct btrfs_qgroup_data_rsv_map; + int btrfs_quota_enable(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info); int btrfs_quota_disable(struct btrfs_trans_handle *trans,