From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:5354 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751979AbcBBDIB (ORCPT ); Mon, 1 Feb 2016 22:08:01 -0500 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: Wang Xiaoguang Subject: [PATCH v5 13/19] btrfs: dedup: Add support to delete hash for on-disk backend Date: Tue, 2 Feb 2016 11:05:45 +0800 Message-Id: <1454382351-31775-14-git-send-email-quwenruo@cn.fujitsu.com> In-Reply-To: <1454382351-31775-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1454382351-31775-1-git-send-email-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Now on-disk backend can delete hash now. Signed-off-by: Wang Xiaoguang Signed-off-by: Qu Wenruo --- fs/btrfs/dedup.c | 100 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) diff --git a/fs/btrfs/dedup.c b/fs/btrfs/dedup.c index c2b6a03..309cbc3 100644 --- a/fs/btrfs/dedup.c +++ b/fs/btrfs/dedup.c @@ -465,6 +465,104 @@ static int inmem_del(struct btrfs_dedup_info *dedup_info, u64 bytenr) return 0; } +/* + * If prepare_del is given, this will setup search_slot() for delete. + * Caller needs to do proper locking. + * + * Return > 0 for found. + * Return 0 for not found. + * Return < 0 for error. + */ +static int ondisk_search_bytenr(struct btrfs_trans_handle *trans, + struct btrfs_dedup_info *dedup_info, + struct btrfs_path *path, u64 bytenr, + int prepare_del) +{ + struct btrfs_key key; + struct btrfs_root *dedup_root = dedup_info->dedup_root; + int ret; + int ins_len = 0; + int cow = 0; + + if (prepare_del) { + if (WARN_ON(trans == NULL)) + return -EINVAL; + cow = 1; + ins_len = -1; + } + + key.objectid = bytenr; + key.type = BTRFS_DEDUP_BYTENR_ITEM_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(trans, dedup_root, &key, path, + ins_len, cow); + + if (ret < 0) + return ret; + /* + * Although it's almost impossible, it's still possible that + * the last 64bits are all 1. + */ + if (ret == 0) + return 1; + + ret = btrfs_previous_item(dedup_root, path, bytenr, + BTRFS_DEDUP_BYTENR_ITEM_KEY); + if (ret < 0) + return ret; + if (ret > 0) + return 0; + return 1; +} + +static int ondisk_del(struct btrfs_trans_handle *trans, + struct btrfs_dedup_info *dedup_info, u64 bytenr) +{ + struct btrfs_root *dedup_root = dedup_info->dedup_root; + struct btrfs_path *path; + struct btrfs_key key; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = bytenr; + key.type = BTRFS_DEDUP_BYTENR_ITEM_KEY; + key.offset = 0; + + mutex_lock(&dedup_info->lock); + + ret = ondisk_search_bytenr(trans, dedup_info, path, bytenr, 1); + if (ret <= 0) + goto out; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + ret = btrfs_del_item(trans, dedup_root, path); + btrfs_release_path(path); + if (ret < 0) + goto out; + /* Search for hash item and delete it */ + key.objectid = key.offset; + key.type = BTRFS_DEDUP_HASH_ITEM_KEY; + key.offset = bytenr; + + ret = btrfs_search_slot(trans, dedup_root, &key, path, -1, 1); + if (WARN_ON(ret > 0)) { + ret = -ENOENT; + goto out; + } + if (ret < 0) + goto out; + ret = btrfs_del_item(trans, dedup_root, path); + +out: + btrfs_free_path(path); + mutex_unlock(&dedup_info->lock); + return ret; +} + /* Remove a dedup hash from dedup tree */ int btrfs_dedup_del(struct btrfs_trans_handle *trans, struct btrfs_dedup_info *dedup_info, u64 bytenr) @@ -474,6 +572,8 @@ int btrfs_dedup_del(struct btrfs_trans_handle *trans, if (dedup_info->backend == BTRFS_DEDUP_BACKEND_INMEMORY) return inmem_del(dedup_info, bytenr); + if (dedup_info->backend == BTRFS_DEDUP_BACKEND_ONDISK) + return ondisk_del(trans, dedup_info, bytenr); return -EINVAL; } -- 2.7.0