From mboxrd@z Thu Jan 1 00:00:00 1970 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 004CEC77B75 for ; Tue, 18 Apr 2023 01:43:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231249AbjDRBnu (ORCPT ); Mon, 17 Apr 2023 21:43:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230257AbjDRBmw (ORCPT ); Mon, 17 Apr 2023 21:42:52 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 801DB55AC for ; Mon, 17 Apr 2023 18:41:48 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 63-20020a250042000000b00b924691cef2so3639141yba.6 for ; Mon, 17 Apr 2023 18:41:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681782108; x=1684374108; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=f+tC+6XFyVz5iTVVtehlShhqqyPSU3xUJhrgatVmT44=; b=rIbd7s/2ek5G8EhMwiYEWTKGjSzZ7qOMthCTcIGG3nURoO/goLZ/THknkdr/Day049 NOH2ThvnPaKS985+9T2Fj65xFkSb8mN7EIMqZpgOoWSQGsC7+K9Lo5IZgHyPfy0r15ie 76fB2pTkT8+QMtmwqL4sijLUqof+ZN+hn8E6tAbc46UFjpy1TcWRQsd5ACEpzyMLSmW0 74VzZ/vHRFvKlgEgwp6sWLYGEao1V0rHzw1TwBzEvw3oDwOtehIqQJ89/IY1OKVdN93F kJFpSyE1Czbvvz7vfD2Xz00Ts/BoJbP3VVBKgAUxrEePjcGseWyzi6UVxppwiAp8z3XC uLNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681782108; x=1684374108; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=f+tC+6XFyVz5iTVVtehlShhqqyPSU3xUJhrgatVmT44=; b=HfEC2tDYDRhzdmxnvKljtL0WmqdOKxSM/5xO8whkIEHKvVGzvur/xJpQ4PfBEw0YpL Cps0Yq49EStT8njQyNg+1X/rCm7Y/kgPHgNhWhLP0DSD2NgybMY6tUBAFTmFJy3xaxew 64zG0L4ISpfB6trNkSzHrQnHhsjDWapLesVQJmUEw3swfzv3xkARZqTPhAWb6iqUhxzp X5+8CMRBNd0xPldWBk9J28PnoISaDZELvxjGpc2ZzZG1nqD8GBOCG02ImjniYhmktkeo Gcfq+QllCaMPT331t7pUaUwTW9HBwDFag2DRdFBSw57MQYkby2c3FrzJ1uCEKwZHypJG jhuA== X-Gm-Message-State: AAQBX9dCFcHyhMxv+2JSLyXVPt587+VRcScrolNZtycJFr+Zl1m/P+j3 g0D+865Rn17W08/oH3pb2Lqdd2u+peg= X-Google-Smtp-Source: AKy350az5srFMYJyfvvtfh6sqad66/N+PonFGFWZFCufX/5Wu37wcKRBKPvzh2skEJqf7c2CQLiJDByUTVw= X-Received: from drosen.mtv.corp.google.com ([2620:15c:211:201:e67a:98b0:942d:86aa]) (user=drosen job=sendgmr) by 2002:a81:ad0e:0:b0:545:6106:5334 with SMTP id l14-20020a81ad0e000000b0054561065334mr10694952ywh.8.1681782108243; Mon, 17 Apr 2023 18:41:48 -0700 (PDT) Date: Mon, 17 Apr 2023 18:40:25 -0700 In-Reply-To: <20230418014037.2412394-1-drosen@google.com> Mime-Version: 1.0 References: <20230418014037.2412394-1-drosen@google.com> X-Mailer: git-send-email 2.40.0.634.g4ca3ef3211-goog Message-ID: <20230418014037.2412394-26-drosen@google.com> Subject: [RFC PATCH v3 25/37] fuse-bpf: allow mounting with no userspace daemon From: Daniel Rosenberg To: Miklos Szeredi , bpf@vger.kernel.org, Alexei Starovoitov Cc: Amir Goldstein , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org, Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Jonathan Corbet , Joanne Koong , Mykola Lysenko , kernel-team@android.com, Daniel Rosenberg , Paul Lawrence Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When using fuse-bpf in pure passthrough mode, we don't explicitly need a userspace daemon. This allows simple testing of the backing operations. Signed-off-by: Daniel Rosenberg Signed-off-by: Paul Lawrence --- fs/fuse/fuse_i.h | 4 ++++ fs/fuse/inode.c | 25 +++++++++++++++++++------ 2 files changed, 23 insertions(+), 6 deletions(-) diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 121d31a04e79..2bd45c8658e8 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -566,6 +566,7 @@ struct fuse_fs_context { bool no_control:1; bool no_force_umount:1; bool legacy_opts_show:1; + bool no_daemon:1; enum fuse_dax_mode dax_mode; unsigned int max_read; unsigned int blksize; @@ -847,6 +848,9 @@ struct fuse_conn { /* Is tmpfile not implemented by fs? */ unsigned int no_tmpfile:1; + /** BPF Only, no Daemon running */ + unsigned int no_daemon:1; + /** The number of requests waiting for completion */ atomic_t num_waiting; diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 3dfb9cfb6e73..31f34962bc9b 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -756,6 +756,7 @@ enum { OPT_MAX_READ, OPT_BLKSIZE, OPT_ROOT_DIR, + OPT_NO_DAEMON, OPT_ERR }; @@ -771,6 +772,7 @@ static const struct fs_parameter_spec fuse_fs_parameters[] = { fsparam_u32 ("blksize", OPT_BLKSIZE), fsparam_string ("subtype", OPT_SUBTYPE), fsparam_u32 ("root_dir", OPT_ROOT_DIR), + fsparam_flag ("no_daemon", OPT_NO_DAEMON), {} }; @@ -860,6 +862,11 @@ static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param) return invalfc(fsc, "Unable to open root directory"); break; + case OPT_NO_DAEMON: + ctx->no_daemon = true; + ctx->fd_present = true; + break; + default: return -EINVAL; } @@ -1419,7 +1426,7 @@ void fuse_send_init(struct fuse_mount *fm) ia->args.nocreds = true; ia->args.end = process_init_reply; - if (fuse_simple_background(fm, &ia->args, GFP_KERNEL) != 0) + if (unlikely(fm->fc->no_daemon) || fuse_simple_background(fm, &ia->args, GFP_KERNEL) != 0) process_init_reply(fm, &ia->args, -ENOTCONN); } EXPORT_SYMBOL_GPL(fuse_send_init); @@ -1694,6 +1701,7 @@ int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) fc->destroy = ctx->destroy; fc->no_control = ctx->no_control; fc->no_force_umount = ctx->no_force_umount; + fc->no_daemon = ctx->no_daemon; err = -ENOMEM; root = fuse_get_root_inode(sb, ctx->rootmode, ctx->root_dir); @@ -1740,7 +1748,7 @@ static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) struct fuse_fs_context *ctx = fsc->fs_private; int err; - if (!ctx->file || !ctx->rootmode_present || + if (!!ctx->file == ctx->no_daemon || !ctx->rootmode_present || !ctx->user_id_present || !ctx->group_id_present) return -EINVAL; @@ -1748,10 +1756,12 @@ static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) * Require mount to happen from the same user namespace which * opened /dev/fuse to prevent potential attacks. */ - if ((ctx->file->f_op != &fuse_dev_operations) || - (ctx->file->f_cred->user_ns != sb->s_user_ns)) - return -EINVAL; - ctx->fudptr = &ctx->file->private_data; + if (ctx->file) { + if ((ctx->file->f_op != &fuse_dev_operations) || + (ctx->file->f_cred->user_ns != sb->s_user_ns)) + return -EINVAL; + ctx->fudptr = &ctx->file->private_data; + } err = fuse_fill_super_common(sb, ctx); if (err) @@ -1801,6 +1811,9 @@ static int fuse_get_tree(struct fs_context *fsc) fsc->s_fs_info = fm; + if (ctx->no_daemon) + return get_tree_nodev(fsc, fuse_fill_super);; + if (ctx->fd_present) ctx->file = fget(ctx->fd); -- 2.40.0.634.g4ca3ef3211-goog