From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:35808 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1758161AbcCVBi4 (ORCPT ); Mon, 21 Mar 2016 21:38:56 -0400 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: Wang Xiaoguang Subject: [PATCH v8 04/27] btrfs: dedupe: Introduce function to remove hash from in-memory tree Date: Tue, 22 Mar 2016 09:35:29 +0800 Message-Id: <1458610552-9845-5-git-send-email-quwenruo@cn.fujitsu.com> In-Reply-To: <1458610552-9845-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1458610552-9845-1-git-send-email-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Wang Xiaoguang Introduce static function inmem_del() to remove hash from in-memory dedupe tree. And implement btrfs_dedupe_del() and btrfs_dedup_destroy() interfaces. Signed-off-by: Qu Wenruo Signed-off-by: Wang Xiaoguang --- fs/btrfs/dedupe.c | 105 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) diff --git a/fs/btrfs/dedupe.c b/fs/btrfs/dedupe.c index 013600a..e44993b 100644 --- a/fs/btrfs/dedupe.c +++ b/fs/btrfs/dedupe.c @@ -257,3 +257,108 @@ int btrfs_dedupe_add(struct btrfs_trans_handle *trans, return inmem_add(dedupe_info, hash); return -EINVAL; } + +static struct inmem_hash * +inmem_search_bytenr(struct btrfs_dedupe_info *dedupe_info, u64 bytenr) +{ + struct rb_node **p = &dedupe_info->bytenr_root.rb_node; + struct rb_node *parent = NULL; + struct inmem_hash *entry = NULL; + + while (*p) { + parent = *p; + entry = rb_entry(parent, struct inmem_hash, bytenr_node); + + if (bytenr < entry->bytenr) + p = &(*p)->rb_left; + else if (bytenr > entry->bytenr) + p = &(*p)->rb_right; + else + return entry; + } + + return NULL; +} + +/* Delete a hash from in-memory dedupe tree */ +static int inmem_del(struct btrfs_dedupe_info *dedupe_info, u64 bytenr) +{ + struct inmem_hash *hash; + + mutex_lock(&dedupe_info->lock); + hash = inmem_search_bytenr(dedupe_info, bytenr); + if (!hash) { + mutex_unlock(&dedupe_info->lock); + return 0; + } + + __inmem_del(dedupe_info, hash); + mutex_unlock(&dedupe_info->lock); + return 0; +} + +/* Remove a dedupe hash from dedupe tree */ +int btrfs_dedupe_del(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, u64 bytenr) +{ + struct btrfs_dedupe_info *dedupe_info = fs_info->dedupe_info; + + if (!fs_info->dedupe_enabled) + return 0; + + if (WARN_ON(dedupe_info == NULL)) + return -EINVAL; + + if (dedupe_info->backend == BTRFS_DEDUPE_BACKEND_INMEMORY) + return inmem_del(dedupe_info, bytenr); + return -EINVAL; +} + +static void inmem_destroy(struct btrfs_dedupe_info *dedupe_info) +{ + struct inmem_hash *entry, *tmp; + + mutex_lock(&dedupe_info->lock); + list_for_each_entry_safe(entry, tmp, &dedupe_info->lru_list, lru_list) + __inmem_del(dedupe_info, entry); + mutex_unlock(&dedupe_info->lock); +} + +int btrfs_dedupe_disable(struct btrfs_fs_info *fs_info) +{ + struct btrfs_dedupe_info *dedupe_info; + int ret; + + /* Here we don't want to increase refs of dedupe_info */ + fs_info->dedupe_enabled = 0; + + dedupe_info = fs_info->dedupe_info; + + if (!dedupe_info) + return 0; + + /* Don't allow disable status change in RO mount */ + if (fs_info->sb->s_flags & MS_RDONLY) + return -EROFS; + + /* + * Wait for all unfinished write to complete dedupe routine + * As disable operation is not a frequent operation, we are + * OK to use heavy but safe sync_filesystem(). + */ + down_read(&fs_info->sb->s_umount); + ret = sync_filesystem(fs_info->sb); + up_read(&fs_info->sb->s_umount); + if (ret < 0) + return ret; + + fs_info->dedupe_info = NULL; + + /* now we are OK to clean up everything */ + if (dedupe_info->backend == BTRFS_DEDUPE_BACKEND_INMEMORY) + inmem_destroy(dedupe_info); + + crypto_free_shash(dedupe_info->dedupe_driver); + kfree(dedupe_info); + return 0; +} -- 2.7.3