From nobody Thu Jan 1 10:40:55 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC114C001E0 for ; Mon, 23 Oct 2023 11:53:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234215AbjJWLxx (ORCPT ); Mon, 23 Oct 2023 07:53:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233957AbjJWLxv (ORCPT ); Mon, 23 Oct 2023 07:53:51 -0400 Received: from out30-124.freemail.mail.aliyun.com (out30-124.freemail.mail.aliyun.com [115.124.30.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8D7DF9; Mon, 23 Oct 2023 04:53:46 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R441e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0VukpfTY_1698062022; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VukpfTY_1698062022) by smtp.aliyun-inc.com; Mon, 23 Oct 2023 19:53:43 +0800 From: Jingbo Xu To: miklos@szeredi.hu, linux-fsdevel@vger.kernel.org Cc: zyfjeff@linux.alibaba.com, linux-kernel@vger.kernel.org Subject: [PATCH] fuse: make delete_stale configurable Date: Mon, 23 Oct 2023 19:53:41 +0800 Message-Id: <20231023115341.60127-1-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Yifei Zhang Fuse tends to cache dentries in LRU list for performance, which makes the fuse server always keep a reference to the opened fd. If the file is deleted by a third party process (neither fuse server nor fuse client), the fuse server will always keep a reference to the deleted file, in which case the deleted file cannot be released. Fix this by making the delete_stale feature configurable. Fuse servers can enable this if a file may be unlinked not through fuse server nor client. Actually virtiofs enables this by default. Make this configurable for other fuse filesystems. Signed-off-by: Yifei Zhang Signed-off-by: Jingbo Xu --- fs/fuse/inode.c | 5 ++++- include/uapi/linux/fuse.h | 2 ++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 2e4eb7cf26fb..635bf0b11147 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1234,6 +1234,8 @@ static void process_init_reply(struct fuse_mount *fm,= struct fuse_args *args, fc->create_supp_group =3D 1; if (flags & FUSE_DIRECT_IO_RELAX) fc->direct_io_relax =3D 1; + if (flags & FUSE_DELETE_STALE) + fc->delete_stale =3D 1; } else { ra_pages =3D fc->max_read / PAGE_SIZE; fc->no_lock =3D 1; @@ -1280,7 +1282,8 @@ void fuse_send_init(struct fuse_mount *fm) FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA | FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT | FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP | - FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_RELAX; + FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_RELAX | + FUSE_DELETE_STALE; #ifdef CONFIG_FUSE_DAX if (fm->fc->dax) flags |=3D FUSE_MAP_ALIGNMENT; diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index db92a7202b34..8d0926d21d2e 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -411,6 +411,7 @@ struct fuse_file_lock { * FUSE_HAS_EXPIRE_ONLY: kernel supports expiry-only entry invalidation * FUSE_DIRECT_IO_RELAX: relax restrictions in FOPEN_DIRECT_IO mode, for n= ow * allow shared mmap + * FUSE_DELETE_STALE: delete dentry if timeout is zero */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -450,6 +451,7 @@ struct fuse_file_lock { #define FUSE_CREATE_SUPP_GROUP (1ULL << 34) #define FUSE_HAS_EXPIRE_ONLY (1ULL << 35) #define FUSE_DIRECT_IO_RELAX (1ULL << 36) +#define FUSE_DELETE_STALE (1ULL << 37) =20 /** * CUSE INIT request/reply flags --=20 2.19.1.6.gb485710b