From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 708DCC43387 for ; Wed, 2 Jan 2019 10:11:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A1E82171F for ; Wed, 2 Jan 2019 10:11:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729283AbfABKLa (ORCPT ); Wed, 2 Jan 2019 05:11:30 -0500 Received: from mx2.suse.de ([195.135.220.15]:49504 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729242AbfABKL3 (ORCPT ); Wed, 2 Jan 2019 05:11:29 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 85A62AF13; Wed, 2 Jan 2019 10:11:27 +0000 (UTC) Subject: Re: [PATCH 3/3] btrfs-progs: Create uuid tree with proper contents To: Nikolay Borisov , Qu Wenruo , linux-btrfs@vger.kernel.org References: <20181227071333.10964-1-wqu@suse.com> <20181227071333.10964-4-wqu@suse.com> <7c7a16cf-a40b-39c0-af05-aca5617dac1c@suse.com> From: Qu Wenruo Openpgp: preference=signencrypt Autocrypt: addr=wqu@suse.de; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0F1F1IFdlbnJ1byA8d3F1QHN1c2UuZGU+iQFUBBMBCAA+AhsDBQsJCAcCBhUICQoLAgQW AgMBAh4BAheAFiEELd9y5aWlW6idqkLhwj2R86El/qgFAlnVgp0FCQlmAm4ACgkQwj2R86El /qilmgf/cUq9kFQo577ku5gc6rFpVg68ublBwjYpwjw0b//xo+Wo1wm+RRbUGs+djSZAqw12 D4F3r0mBTI7abUCNWAbFkYZSAIFVi0DMkjypIVS7PSaEt04rM9VBTToE+YqU6WENeJ57R2p2 +hI0wZrBwxObdsdaOtxWtsp3bmhIbdqxSKrtXuRawy4KnQYcLuGzOce9okdlbAE0W3KHm1gQ oNAe6FX8nC9qo14m8LqEbThYH+qj4iCMlN8HIfbSx4F3e7nHZ+UAMW+E/lnMRkIB9Df+JyVd /NlXzIjZAggcWsqpx6D4wyAuexKWkiGQeUeArUNihAwXjmyqWPGmjVyIh+oC6LkBDQRZ1YGv AQgAqlPrYeBLMv3PAZ75YhQIwH6c4SNcB++hQ9TCT5gIQNw51+SQzkXIGgmzxMIS49cZcE4K Xk/kHw5hieQeQZa60BWVRNXwoRI4ib8okgDuMkD5Kz1WEyO149+BZ7HD4/yK0VFJGuvDJR8T 7RZwB69uVSLjkuNZZmCmDcDzS0c/SJOg5nkxt1iTtgUETb1wNKV6yR9XzRkrEW/qShChyrS9 fNN8e9c0MQsC4fsyz9Ylx1TOY/IF/c6rqYoEEfwnpdlz0uOM1nA1vK+wdKtXluCa79MdfaeD /dt76Kp/o6CAKLLcjU1Iwnkq1HSrYfY3HZWpvV9g84gPwxwxX0uXquHxLwARAQABiQE8BBgB CAAmFiEELd9y5aWlW6idqkLhwj2R86El/qgFAlnVga8CGwwFCQPCZwAACgkQwj2R86El/qgN 8Qf+M0vM2Idwm5txZZSs+/kSgcPxEwYmxUinnUJGyc0ZWYQXPl0cBetZon9El0naijGzNWvf HxIPB+ZFehk6Otgc78p1a3/xck/s1myFRLrmbbTJNoFiyL25ljcq0J8z5Zp4yuABL2RiLdaZ Pt/jfwjBHwGR+QKp6dD2qMrUWf9b7TFzYDMZXzZ2/eoIgtyjEelNBPrIgOFe24iKMjaGjd97 fJuRcBMHdhUAxvXQF1oRtd83JvYJ5OtwTd8MgkEfl+fo7HwWkuHbzc70L4fFKv2BowqFdaHy mId1ijGPGr46tuZ5a4cw/zbaPYx6fJ4sK9tSv/6V1QPNUdqml6hm6pfs6A== Message-ID: <370bbd32-3b5e-cd40-4b1e-95d99f05c62e@suse.de> Date: Wed, 2 Jan 2019 18:11:23 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.3 MIME-Version: 1.0 In-Reply-To: <7c7a16cf-a40b-39c0-af05-aca5617dac1c@suse.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2019/1/2 下午6:07, Nikolay Borisov wrote: > > > On 2.01.19 г. 12:00 ч., Qu Wenruo wrote: >> > > > >>>> +} >>>> >>>> +/* >>>> + * Create a tree containing an root inode >>>> + * >>>> + * Caller must ensure at the time of calling, fs tree only contains 2 items >>>> + * (one for INODE_ITEM and one for INODE_REF) >>>> + */ >>>> +int create_inode_tree(struct btrfs_trans_handle *trans, u64 objectid) >>> >>> This function is really misnamed, since it's creating the >>> DATA_RELOC_TREE, yet it's called create_inode_tree. Why not simply >>> create_data_reloc_tree or are you planning on using this function more >>> than once? >> >> In fact this could be used for fs, data reloc, and all subvolume trees. >> >> That's my primary reason not naming it create_data_reloc_tree(). >> Although currently it's only used by data reloc tree. >> >>> >>>> +{ >>>> + struct btrfs_root *fs_root = trans->fs_info->fs_root; >>>> + >>>> + ASSERT(btrfs_header_level(fs_root->node) == 0 && >>>> + btrfs_header_nritems(fs_root->node) == 2); >>>> + return __create_tree(trans, fs_root, objectid); >>>> +} >>>> + >>>> +int create_uuid_tree(struct btrfs_trans_handle *trans) >>>> +{ >>>> + struct btrfs_fs_info *fs_info = trans->fs_info; >>>> + struct btrfs_root *uuid_root = fs_info->uuid_root; >>>> + struct btrfs_key key; >>>> + int ret; >>>> + >>>> + if (!uuid_root) { >>> >>> Isn't this always true, so the conditional here is redundant? >> Just a much better solution than ASSERT()/BUG_ON(). >> >> It won't hurt and will handle wrong calling order. > > What will the wrong calling order be? The only error that's possible is > if someone calls this function twice or creates the tree outside of this > api. This could only occur if someone is deliberately touching modifying > the code in which case a trigger of an ASSERT should suffice to force > them to think about what they are doing. OK, I'll change it to ASSERT(). Thanks, Qu > >> >> Thanks, >> Qu >> > > >