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Message-ID: <7c6f4134-b01c-4ec6-a036-d92c5336839c@kernel.org>
Date: Sat, 18 Apr 2026 09:11:29 +0800
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Cc: chao@kernel.org, Akilesh Kailash <akailash@google.com>
Subject: Re: [f2fs-dev] [PATCH v2] f2fs: another way to set large folio by
 remembering inode number
To: Jaegeuk Kim <jaegeuk@kernel.org>, linux-kernel@vger.kernel.org,
 linux-f2fs-devel@lists.sourceforge.net
References: <20260409134538.3692605-1-jaegeuk@kernel.org>
 <adhPZxtbZxgU-37v@google.com>
Content-Language: en-US
From: Chao Yu <chao@kernel.org>
In-Reply-To: <adhPZxtbZxgU-37v@google.com>
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On 4/10/2026 9:16 AM, Jaegeuk Kim via Linux-f2fs-devel wrote:
> enum {
>         F2FS_XATTR_FADV_LARGEFOLIO,
> };
> 
> unsigned int value = BIT(F2FS_XATTR_FADV_LARGEFOLIO);
> 
> 1. setxattr(file, "user.fadvise", &value, sizeof(unsigned int), 0)
>   -> register the inode number for large folio
> 2. chmod(0400, file)
>   -> make Read-Only
> 3. fsync() && close() && open(READ)
>   -> f2fs_iget() with large folio
> 4. open(WRITE), mkwrite on mmap, chmod(WRITE)
>   -> return error
> 5. close() and open()
>   -> goto #3
> 6. unlink
>   -> deregister the inode number
> 
> Suggested-by: Akilesh Kailash <akailash@google.com>
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,