Received-SPF: pass (google.com: domain of linux-kernel+bounces-111403-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Subject: Re: [RFC PATCH 2/5] ubifs: Initialize or update ACLs for inode
To: Li Zetao <lizetao1@huawei.com>, <richard@nod.at>,
	<kent.overstreet@linux.dev>, <agruenba@redhat.com>
CC: <linux-kernel@vger.kernel.org>, <linux-mtd@lists.infradead.org>
References: <20240319161646.2153867-1-lizetao1@huawei.com>
 <20240319161646.2153867-3-lizetao1@huawei.com>
 <2991c168-723d-48ef-8420-61e22a897239@huawei.com>
 <661736fb-bb3c-3519-1f4b-44dff285ea0b@huawei.com>
From: Zhihao Cheng <chengzhihao1@huawei.com>
Message-ID: <10859a10-5c31-a5ec-02f5-47216132cf01@huawei.com>
Date: Fri, 22 Mar 2024 20:07:02 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.5.0
Precedence: bulk
MIME-Version: 1.0
In-Reply-To: <661736fb-bb3c-3519-1f4b-44dff285ea0b@huawei.com>
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Transfer-Encoding: 8bit

在 2024/3/22 19:57, Li Zetao 写道:
> Hi,
> 
> On 2024/3/21 11:47, Zhihao Cheng wrote:
>> 在 2024/3/20 0:16, Li Zetao 写道:
>>> There are two scenarios where ACL needs to be updated, the first one
>>> is when creating the inode, and the second one is in the chmod process.
>>> When creating directories/files/device node/tmpfile, ACLs needs to be
>>> initialized, but symlink do not.Why not support symlink? It looks 
>>> like many filesystems(eg. ext4, f2fs, 
>> btrfs) support it, except xfs.
> Thanks for the reviews, but this is inconsistent with my understanding.
> I think most file systems in Linux do not support it, because most file 
> systems do not register the get/set functions of ACLs for symlink 
> operations. And the posix_acl_create() will determine that it is a 
> symlink type inode, and then skip the creation process. But except for 
> bcachefs, it may be to solve the problem of certain scenarios, so it 
> would be nice if anyone could explain it to us.

You are right, only bcachefs support acl for symlink.