From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:22441 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752006AbcDZDtl (ORCPT ); Mon, 25 Apr 2016 23:49:41 -0400 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz, Lu Fengqi Subject: [PATCH RFC 11/16] btrfs-progs: fsck: Introduce function to check block group item Date: Tue, 26 Apr 2016 11:48:58 +0800 Message-Id: <1461642543-4621-12-git-send-email-quwenruo@cn.fujitsu.com> In-Reply-To: <1461642543-4621-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1461642543-4621-1-git-send-email-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Lu Fengqi Introduce function check_block_group_item() to check a block group item. It will check the referencer chunk and the used space accounting with extent tree. Signed-off-by: Lu Fengqi Signed-off-by: Qu Wenruo --- cmds-check.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) diff --git a/cmds-check.c b/cmds-check.c index e2d1ebf..b9fbb02 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -329,6 +329,7 @@ struct root_item_info { #define BAD_ITEM_SIZE (1 << 5) /* Bad item size */ #define UNKNOWN_TYPE (1 << 6) /* Unknown type */ #define ACCOUNTING_MISMATCH (1 << 7) /* Used space accounting error */ +#define MISMATCH_TYPE (1 << 8) static void *print_status_check(void *p) { @@ -9247,6 +9248,121 @@ next: return 0; } +/* + * Check a block group item with its referener(chunk) and its used space + * with extent/metadata item + */ +static int check_block_group_item(struct btrfs_fs_info *fs_info, + struct extent_buffer *eb, int slot) +{ + struct btrfs_root *extent_root = fs_info->extent_root; + struct btrfs_root *chunk_root = fs_info->chunk_root; + struct btrfs_block_group_item *bi; + struct btrfs_block_group_item bg_item; + struct btrfs_path path; + struct btrfs_key key; + struct btrfs_key found_key; + struct btrfs_chunk *chunk; + struct extent_buffer *leaf; + struct btrfs_extent_item *ei; + u32 nodesize = btrfs_super_nodesize(fs_info->super_copy); + u64 flags; + u64 bg_flags; + u64 used; + u64 total = 0; + int ret; + int err = 0; + + btrfs_item_key_to_cpu(eb, &found_key, slot); + bi = btrfs_item_ptr(eb, slot, struct btrfs_block_group_item); + read_extent_buffer(eb, &bg_item, (unsigned long)bi, sizeof(bg_item)); + used = btrfs_block_group_used(&bg_item); + bg_flags = btrfs_block_group_flags(&bg_item); + + key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; + key.type = BTRFS_CHUNK_ITEM_KEY; + key.offset = found_key.objectid; + + btrfs_init_path(&path); + /* Search for the referencer chunk */ + ret = btrfs_search_slot(NULL, chunk_root, &key, &path, 0, 0); + if (ret) { + error("Block group[%llu %llu] didn't find the releative chunk item", + found_key.objectid, found_key.offset); + err |= MISSING_REFERENCER; + } else { + chunk = btrfs_item_ptr(path.nodes[0], path.slots[0], + struct btrfs_chunk); + if (btrfs_chunk_length(path.nodes[0], chunk) != + found_key.offset) { + error("Block group[%llu %llu] relative chunk item length don't match", + found_key.objectid, found_key.offset); + err |= BAD_REFERENCER; + } + } + btrfs_release_path(&path); + + key.objectid = 0; + key.type = BTRFS_METADATA_ITEM_KEY; + key.offset = found_key.objectid; + + btrfs_init_path(&path); + ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0); + if (ret < 0) + goto out; + + /* Iterate extent tree to account used space */ + while (1) { + leaf = path.nodes[0]; + btrfs_item_key_to_cpu(leaf, &key, path.slots[0]); + if (key.objectid >= found_key.objectid + found_key.offset) + break; + + if (key.type != BTRFS_METADATA_ITEM_KEY && + key.type != BTRFS_EXTENT_ITEM_KEY) + goto next; + if (key.objectid < found_key.objectid) + goto next; + + if (key.type == BTRFS_METADATA_ITEM_KEY) + total += nodesize; + else + total += key.offset; + + ei = btrfs_item_ptr(leaf, path.slots[0], + struct btrfs_extent_item); + flags = btrfs_extent_flags(leaf, ei); + if (flags & BTRFS_EXTENT_FLAG_DATA) { + if (!(bg_flags & BTRFS_BLOCK_GROUP_DATA)) { + error("bad extent[%llu, %llu) type mismatch with chunk", + key.objectid, key.objectid + key.offset); + err |= MISMATCH_TYPE; + } + } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + if (!(bg_flags & (BTRFS_BLOCK_GROUP_SYSTEM | + BTRFS_BLOCK_GROUP_METADATA))) { + error("bad extent[%llu, %llu) type mismatch with chunk", + key.objectid, key.objectid + nodesize); + err |= MISMATCH_TYPE; + } + } +next: + ret = btrfs_next_item(extent_root, &path); + if (ret) + break; + } + +out: + btrfs_release_path(&path); + + if (total != used) { + error("Block group[%llu %llu] used(%llu) but extent items used(%llu)", + found_key.objectid, found_key.offset, used, total); + err |= ACCOUNTING_MISMATCH; + } + return -err; +} + static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, int overwrite) { -- 2.8.0