From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.cn.fujitsu.com ([183.91.158.132]:56162 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752069AbeC0HHT (ORCPT ); Tue, 27 Mar 2018 03:07:19 -0400 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id 3F89748AE76C for ; Tue, 27 Mar 2018 15:07:10 +0800 (CST) From: Lu Fengqi To: Subject: [PATCH v2 07/10] btrfs-progs: undelete-subvol: introduce btrfs_undelete_intact_subvols Date: Tue, 27 Mar 2018 15:06:55 +0800 Message-ID: <20180327070658.13064-8-lufq.fnst@cn.fujitsu.com> In-Reply-To: <20180327070658.13064-1-lufq.fnst@cn.fujitsu.com> References: <20180327070658.13064-1-lufq.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-btrfs-owner@vger.kernel.org List-ID: The function default will traverse the all orphan items on the tree root, and recover the all intact subvolumes. If subvol_id is specified, then only the corresponding subvolume will be recovered. Signed-off-by: Lu Fengqi --- v2: add subvol_id argumenta to specify subvol_id instead of recovering all subvolumes. undelete-subvol.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ undelete-subvol.h | 2 ++ 2 files changed, 72 insertions(+) diff --git a/undelete-subvol.c b/undelete-subvol.c index 9243e35545c5..5b494ca086ab 100644 --- a/undelete-subvol.c +++ b/undelete-subvol.c @@ -15,6 +15,7 @@ #include "transaction.h" #include "disk-io.h" #include "messages.h" +#include "undelete-subvol.h" /* * Determines whether the subvolume is intact, according to the drop_progress @@ -182,3 +183,72 @@ static int link_subvol_to_lostfound(struct btrfs_root *root, u64 subvol_id) out: return ret; } + +/* + * Traverse all orphan items on the root tree, restore them to the lost+found + * directory if the corresponding subvolumes are still intact left on the disk. + * + * @root the root of the root tree. + * @subvol_id if not set to 0, skip other subvolumes and only recover the + * subvolume specified by @subvol_id. + * + * Return 0 if no error occurred even if no subvolume was recovered. + */ +int btrfs_undelete_intact_subvols(struct btrfs_root *root, u64 subvol_id) +{ + struct btrfs_key key; + struct btrfs_path path; + u64 found_count = 0; + u64 recovered_count = 0; + int ret = 0; + + key.objectid = BTRFS_ORPHAN_OBJECTID; + key.type = BTRFS_ORPHAN_ITEM_KEY; + key.offset = subvol_id ? subvol_id + 1 : (u64)-1; + + btrfs_init_path(&path); + while (subvol_id != key.offset) { + ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0); + if (ret < 0) { + error("search ORPHAN_ITEM for %llu failed.\n", + key.offset); + break; + } + + path.slots[0]--; + btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); + + btrfs_release_path(&path); + + /* No more BTRFS_ORPHAN_ITEM, so we don't need to continue. */ + if (key.type != BTRFS_ORPHAN_ITEM_KEY) { + ret = 0; + break; + } + + /* If subvol_id is non-zero, skip other deleted subvolume. */ + if (subvol_id && subvol_id != key.offset) { + ret = -ENOENT; + break; + } + + if (!is_subvol_intact(root, key.offset)) + continue; + + /* Here we can confirm there is an intact subvolume. */ + found_count++; + ret = link_subvol_to_lostfound(root, key.offset); + if (ret == 0) { + recovered_count++; + printf( + "Recovered subvolume %llu to lost+found successfully.\n", + key.offset); + } + + } + + printf("Found %llu subvols left intact\n", found_count); + printf("Recovered %llu subvols\n", found_count); + + return ret; +} diff --git a/undelete-subvol.h b/undelete-subvol.h index 7cfd100cce37..f773210c46fe 100644 --- a/undelete-subvol.h +++ b/undelete-subvol.h @@ -14,4 +14,6 @@ #ifndef __BTRFS_UNDELETE_SUBVOLUME_H__ #define __BTRFS_UNDELETE_SUBVOLUME_H__ +int btrfs_undelete_intact_subvols(struct btrfs_root *root, u64 subvol_id); + #endif -- 2.16.2