From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-97.freemail.mail.aliyun.com (out30-97.freemail.mail.aliyun.com [115.124.30.97]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 223E72B2DA; Tue, 23 Dec 2025 08:31:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.97 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766478708; cv=none; b=H4oEFIGI96NVWHLqHFmmmnHYk0hiFqQ4tgb4Nn1CMbKJypuUIhmGTJDfxFsODY/9A+Q+fJYWtNex5WbBFCbx/MvtpRnzoutRJ2aTjzGw+Iysamw9A7z4SYlRYIkBFJ05umAR2KEMSW0WUElSMpoMyKMeh2oLA5N/7I5iq3ZjLIg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766478708; c=relaxed/simple; bh=ykGDQCSJ9XGA/4GWYP2glmDLZ1AnpuTUrnuz1969ddM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=L4lucF6tVinxUFcFlWe1amCqNJVpv390OUT61EDhfPMGJ1xAvOTkxN3MdzIiNJZcuOdgdEmFyj2JCSb4bIzLQgnWAgBNzdsB/lyNKbt8tEowR2990M4pYN0vPZjw4cc7YdO4+JOygsvNHURJehLSCmQY3V32UCQuSfp6IbXV+48= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=JO4P0RhA; arc=none smtp.client-ip=115.124.30.97 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="JO4P0RhA" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1766478703; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=QDHZ4gEUp+iF2Zx/V1T92i7/2FBuX9i2CFTDzZA/ECA=; b=JO4P0RhAqRM48h+VPHOpk5Qho1gwxqBVud+SCuavqBtNDpfD4BAcMfvY09ZdJJysKIGW02GJVDabm9c8ZzU+641acZd+ZKsxLHIDqYbkM6Y/Xf50yM4hi4aPRhy7jqP40fO9UsyHtxCsPkV5MIL0kzhEveFjkttJz3UmpgihPco= Received: from 30.221.131.244(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WvX.job_1766478702 cluster:ay36) by smtp.aliyun-inc.com; Tue, 23 Dec 2025 16:31:43 +0800 Message-ID: Date: Tue, 23 Dec 2025 16:31:42 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 03/10] fs: Export alloc_empty_backing_file To: Hongbo Li , Amir Goldstein Cc: linux-fsdevel@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, Chao Yu , Christian Brauner , "Darrick J. Wong" , Christoph Hellwig References: <20251223015618.485626-1-lihongbo22@huawei.com> <20251223015618.485626-4-lihongbo22@huawei.com> From: Gao Xiang In-Reply-To: <20251223015618.485626-4-lihongbo22@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2025/12/23 09:56, Hongbo Li wrote: > There is no need to open nonexistent real files if backing files > couldn't be backed by real files (e.g., EROFS page cache sharing > doesn't need typical real files to open again). > > Therefore, we export the alloc_empty_backing_file() helper, allowing > filesystems to dynamically set the backing file without real file > open. This is particularly useful for obtaining the correct @path > and @inode when calling file_user_path() and file_user_inode(). > > Signed-off-by: Hongbo Li Reviewed-by: Gao Xiang (I hope Amir could ack this particular patch too..) Thanks, Gao Xiang