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Subject: Re: [f2fs-dev] [PATCH 2/2] f2fs: introduce FI_COMPRESS_RELEASED
 instead of using IMMUTABLE bit
To:     Jaegeuk Kim <jaegeuk@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
References: <20210525204955.2512409-1-jaegeuk@kernel.org>
 <20210525204955.2512409-2-jaegeuk@kernel.org>
 <95b5669f-a521-5865-2089-320e2a2493de@kernel.org>
 <YL5P15nLsc/3GQOY@google.com>
 <3f2c2543-c8a4-3477-76af-5c7614b643e8@kernel.org>
 <YMEL06gZC5n3J2bX@google.com>
From:   Chao Yu <chao@kernel.org>
Message-ID: <a7a3078e-918d-53f2-6bff-537934094631@kernel.org>
Date:   Thu, 10 Jun 2021 23:24:37 +0800
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On 2021/6/10 2:43, Jaegeuk Kim wrote:
> On 06/08, Chao Yu wrote:
>> On 2021/6/8 0:56, Jaegeuk Kim wrote:
>>> On 06/06, Chao Yu wrote:
>>>> On 2021/5/26 4:49, Jaegeuk Kim wrote:
>>>>> Once we release compressed blocks, we used to set IMMUTABLE bit. But it turned
>>>>> out it disallows every fs operations which we don't need for compression.
>>>>>
>>>>> Let's just prevent writing data only.
>>>>>
>>>>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
>>>>
>>>> Reviewed-by: Chao Yu <yuchao0@huawei.com>
>>>>
>>>> BTW, we need to expose .i_inline field to userspace since there is no
>>>> way to check status of inode whether it has released blocks?
>>>
>>> Need to add some in F2FS_IOC_GET_COMPRESS_OPTION?
>>
>> We should not change this interface, in order to keep its compatibility for
>> userspace usage. How about adding it in F2FS_IOC_GET_COMPRESS_OPTION_EX?
> 
> Hmm, or need to add it in getflags?

Not sure whether the flag may conflict with the bit FS_*_FL used in
lsattr/chattr.

Thanks,

> 
>>
>> Thanks,
>>
>>>
>>>>
>>>> Thanks,